A custom processor for protocol-independent packet parsing

Networking devices such as switches and routers have traditionally had fixed functionality. They have the logic for the union of network protocols matching the application and market segment for which they have been designed. Possibility of adding new functionality is limited. One of the aims of Software Defined Networking is to make packet processing devices programmable. This provides for innovation and rapid deployment of novel networking protocols. The first step in processing of packets is packet parsing. In this paper, we present a custom processor for packet parsing. The parser is protocol-independent and can be programmed to parse any sequence of headers. It does so without the use of a Ternary Content Addressable Memory. As a result, the area and power consumption are noticeably smaller than in the state of the art. Moreover, its output is the same as that of the parser used in the Reconfigurable Match Tables (RMT). With an area no more than that of parsers in the RMT architecture, it sustains aggregate throughput of 3.4 Tbps in the worst case which is an improvement by a factor of 5.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Electrical Engineering, Research area: Computer engineering, University of Bologna
Contributors: Zolfaghari, H., Rossi, D., Nurmi, J.
Number of pages: 11
Publication date: 1 Feb 2020
Peer-reviewed: Yes
Early online date: 2019

Publication information

Journal: Microprocessors and Microsystems
Volume: 72
ISSN (Print): 0141-9331
Original language: English
ASJC Scopus subject areas: Software, Hardware and Architecture, Computer Networks and Communications, Artificial Intelligence
Keywords: Advanced program control, Packet parsing, Programmable data plane, Software defined networking
Source: Scopus
Source ID: 85074246120

Research output: Contribution to journalArticleScientificpeer-review

Systematic integration of flowgraph- and module-level parallelism in implementation of DSP applications on multiprocessor systems-on-chip

Increasing use of multiprocessor system-on-chip (MPSoC) technology is an important trend in the design and implementation of signal processing systems. However, the design of efficient DSP software for MPSoC platforms involves complex inter-related steps, including data decomposition, memory management, and inter-task and inter-thread synchronization. These design steps are challenging, especially under strict constraints on performance and power consumption, and tight time to market pressures. To facilitate these steps, we have developed a new dataflow based design flow within the targeted dataflow interchange format (TDIF) design tool. Our new MPSoC-oriented design flow, called TDIF-PPG, is geared towards analysis and mapping of embedded DSP applications on MPSoCs. An important feature of TDIF-PPG is its capability to integrate graph level parallelism for DSP system flowgraphs and actor level parallelism for DSP functional modules into the application mapping processing. Here, graph level parallelism is exposed by the dataflow graph application representation in TDIF, and actor level parallelism is modeled by a novel model for multiprocessor dataflow graph implementation that we call the parallel processing group (PPG) model. We demonstrate our approach through actor and subsystem design for software defined radio.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing Research Community (SPRC), University of Maryland, Department of Electrical and Computer Engineering
Contributors: Zhou, Z., Shen, C. C., Plishker, W., Wu, H. H., Bhattacharyya, S. S.
Number of pages: 7
Pages: 402-408
Publication date: 2012

Host publication information

Title of host publication: ICSP 2012 - 2012 11th International Conference on Signal Processing, Proceedings
Volume: 1
Article number: 6491686
ISBN (Print): 9781467321945
ASJC Scopus subject areas: Software, Signal Processing, Computer Science Applications
Source: Scopus
Source ID: 84876463174

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

A k-nearest neighbor multilabel ranking algorithm with application to content-based image retrieval

Multilabel ranking is an important machine learning task with many applications, such as content-based image retrieval (CBIR). However, when the number of labels is large, traditional algorithms are either infeasible or show poor performance. In this paper, we propose a simple yet effective multilabel ranking algorithm that is based on k-nearest neighbor paradigm. The proposed algorithm ranks labels according to the probabilities of the label association using the neighboring samples around a query sample. Different from traditional approaches, we take only positive samples into consideration and determine the model parameters by directly optimizing ranking loss measures. We evaluated the proposed algorithm using four popular multilabel datasets. The proposed algorithm achieves equivalent or better performance than other instance-based learning algorithms. When applied to a CBIR system with a dataset of 1 million samples and over 190 thousand labels, which is much larger than any other multilabel datasets used earlier, the proposed algorithm clearly outperforms the competing algorithms.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing, Research group: Multimedia Research Group - MRG, Qatar University
Contributors: Zhang, H., Kiranyaz, S., Gabbouj, M.
Number of pages: 5
Pages: 2587-2591
Publication date: 16 Jun 2017

Host publication information

Title of host publication: 2017 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2017 - Proceedings
Publisher: IEEE
ISBN (Electronic): 9781509041176
ASJC Scopus subject areas: Software, Signal Processing, Electrical and Electronic Engineering
Keywords: Content-Based Image Retrieval, k-Nearest Neighbor, Multilabel Learning
Source: Scopus
Source ID: 85023746875

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Still image/video frame lossy compression providing a desired visual quality

The problem of how to automatically provide a desired (required) visual quality in lossy compression of still images and video frames is considered in this paper. The quality can be measured based on different conventional and visual quality metrics. In this paper, we mainly employ human visual system (HVS) based metrics PSNR-HVS-M and MSSIM since both of them take into account several important peculiarities of HVS. To provide a desired visual quality with high accuracy, iterative image compression procedures are proposed and analyzed. An experimental study is performed for a large number of grayscale test images. We demonstrate that there exist several coders for which the number of iterations can be essentially decreased using a reasonable selection of the starting value and the variation interval for the parameter controlling compression (PCC). PCC values attained at the end of the iterative procedure may heavily depend upon the coder used and the complexity of the image. Similarly, the compression ratio also considerably depends on the above factors. We show that for some modern coders that take HVS into consideration it is possible to give practical recommendations on setting a fixed PCC to provide a desired visual quality in a non-iterative manner. The case when original images are corrupted by visible noise is also briefly studied.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Signal Processing, Research group: Computational Imaging-CI, National Aerospace University
Contributors: Zemliachenko, A., Lukin, V., Ponomarenko, N., Egiazarian, K., Astola, J.
Pages: 697-718
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: Multidimensional Systems and Signal Processing
Volume: 27
Issue number: 3
ISSN (Print): 0923-6082
Ratings: 
  • Scopus rating (2016): CiteScore 3.4 SJR 0.424 SNIP 1.109
Original language: English
ASJC Scopus subject areas: Computer Science Applications, Information Systems, Signal Processing, Software, Artificial Intelligence, Hardware and Architecture, Applied Mathematics
Keywords: Compression ratio, Lossy compression, Required quality, Visual quality metrics
Source: Scopus
Source ID: 84930357751

Research output: Contribution to journalArticleScientificpeer-review

Deep Reinforcement Learning for Financial Trading Using Price Trailing

Developing accurate financial analysis tools can be useful both for speculative trading, as well as for analyzing the behavior of markets and promptly responding to unstable conditions ensuring the smooth operation of the financial markets. This led to the development of various methods for analyzing and forecasting the behaviour of financial assets, ranging from traditional quantitative finance to more modern machine learning approaches. However, the volatile and unstable behavior of financial markets forbids the accurate prediction of future prices, reducing the performance of these approaches. In contrast, in this paper we propose a novel price trailing method that goes beyond traditional price forecasting by reformulating trading as a control problem, effectively overcoming the aforementioned limitations. The proposed method leads to developing robust agents that can withstand large amounts of noise, while still capturing the price trends and allowing for taking profitable decisions.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Aristotle University of Thessaloniki, School of Informatics
Contributors: Zarkias, K. S., Passalis, N., Tsantekidis, A., Tefas, A.
Number of pages: 5
Pages: 3067-3071
Publication date: 1 May 2019

Host publication information

Title of host publication: 2019 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2019 - Proceedings
Publisher: IEEE
ISBN (Electronic): 9781479981311
ASJC Scopus subject areas: Software, Signal Processing, Electrical and Electronic Engineering
Keywords: Deep Reinforcement Learning, Financial Markets, Price Forecasting, Trading

Bibliographical note

EXT="Tefas, Anastasios"

Source: Scopus
Source ID: 85068989312

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Real-time online drilling vibration analysis using data mining

While the data mining intermediaries play a critical role in the rock drilling industry, they also tend to provide an optimized real-time model for the drilling systems. In addition, proper online tool condition monitoring (OTOM) methods can improve the drilling performance by accessing real-time data. Hence, OTOM methods assist depreciating error and detect unspecified faults at early stages. In this study, we proposed appropriate OTOM algorithms to develop and enhance the quality of real-time systems and provide a solution to detect and categorize various stages of drilling operation with the aid of vibration signals (especially in terms of acceleration or velocity). In particular, the proposed methods in this article perform based on statistical approaches. Therefore, in order to recognize the drilling stages, we measured the Root Mean Square (RMS) values corresponding to the acceleration signals. In the meantime, we also succeeded to distinguish the drilling stages by employing estimated power spectral density (PSD) in the frequency domain. The acquired results in this publication confirm the real-time prediction and classification potential of the proposed methods for the different drilling stages and especially for the rock drilling engineering.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Automation Technology and Mechanical Engineering, Research group: Innovative Hydraulic Automation, Research group: MMDM, Tamlink Oy, Sandvik Mining and Construction Oy
Contributors: Zare, M., Huova, M., Visa, A., Launis, S.
Number of pages: 6
Pages: 175-180
Publication date: 19 Jul 2019

Host publication information

Title of host publication: Proceedings of the 2019 2nd International Conference on Data Science and Information Technology, DSIT 2019
Publisher: ACM
ISBN (Electronic): 9781450371414
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Data mining, Drilling stages, Real-time, Statistical analysis
Source: Scopus
Source ID: 85072810540

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Automated design of networks of transport-triggered architecture processors using dynamic dataflow programs

Modern embedded systems show a clear trend towards the use of Multiprocessor System-on-Chip (MPSoC) architectures in order to handle the performance and power consumption constraints. However, the design and validation of dedicated MPSoCs is an extremely hard and expensive task due to their complexity. Thus, the development of automated design processes is of highest importance to satisfy the time-to-market pressure of embedded systems. This paper proposes an automated co-design flow based on the high-level language-based approach of the Reconfigurable Video Coding framework. The designer provides the application description in the RVC-CAL dataflow language, after which the presented co-design flow automatically generates a network of heterogeneous processors that can be synthesized on FPGA chips. The synthesized processors are Very Long Instruction Word-style processors. Such a methodology permits the rapid design of a many-core signal processing system which can take advantage of all levels of parallelism. The toolchain functionality has been demonstrated by synthesizing an MPEG-4 Simple Profile video decoder to two different FPGA boards. The decoder is realized into 18 processors that decode QCIF resolution video at 45 frames per second on a 50 MHz FPGA clock frequency. The results show that the given application can take advantage of every level of parallelism.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Signal Processing Research Community (SPRC), Universite de Rennes, CSE Department, Univ of Oulu, UBL
Contributors: Yviquel, H., Boutellier, J., Raulet, M., Casseau, E.
Number of pages: 8
Pages: 1295-1302
Publication date: Nov 2013
Peer-reviewed: Yes

Publication information

Journal: Signal Processing: Image Communication
Volume: 28
Issue number: 10
ISSN (Print): 0923-5965
Ratings: 
  • Scopus rating (2013): CiteScore 3.2 SJR 0.407 SNIP 1.301
Original language: English
ASJC Scopus subject areas: Software, Signal Processing, Computer Vision and Pattern Recognition, Electrical and Electronic Engineering
Keywords: Co-design, Dataflow programming, Multi-Processor System-on-Chip (MPSoC), Reconfigurable Video Coding (RVC), Transport-Trigger Architecture (TTA)
Source: Scopus
Source ID: 84888203042

Research output: Contribution to journalArticleScientificpeer-review

Multi-view predictive latent space learning

In unsupervised circumstances, multi-view learning seeks a shared latent representation by taking the consensus and complementary principles into account. However, most existing multi-view unsupervised learning approaches do not explicitly lay stress on the predictability of the latent space. In this paper, we propose a novel multi-view predictive latent space learning (MVP) model and apply it to multi-view clustering and unsupervised dimension reduction. The latent space is forced to be predictive by maximizing the correlation between the latent space and feature space of each view. By learning a multi-view graph with adaptive view-weight learning, MVP effectively combines the complementary information from multi-view data. Experimental results on benchmark datasets show that MVP outperforms the state-of-the-art multi-view clustering and unsupervised dimension reduction algorithms.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Signal Processing, Tianjin University
Contributors: Yuan, J., Gao, K., Zhu, P., Egiazarian, K.
Publication date: 2018
Peer-reviewed: Yes
Early online date: 2018

Publication information

Journal: Pattern Recognition Letters
ISSN (Print): 0167-8655
Ratings: 
  • Scopus rating (2018): CiteScore 5.8 SJR 0.662 SNIP 1.729
Original language: English
ASJC Scopus subject areas: Software, Signal Processing, Computer Vision and Pattern Recognition, Artificial Intelligence
Keywords: Multi-view learning, Predictive latent space learning, Unsupervised clustering, Unsupervised dimension reduction
Source: Scopus
Source ID: 85049094619

Research output: Contribution to journalArticleScientificpeer-review

Hermitian normalized Laplacian matrix for directed networks

In this paper, we extend and generalize the spectral theory of undirected networks towards directed networks by introducing the Hermitian normalized Laplacian matrix for directed networks. In order to start, we discuss the Courant–Fischer theorem for the eigenvalues of Hermitian normalized Laplacian matrix. Based on the Courant–Fischer theorem, we obtain a similar result towards the normalized Laplacian matrix of undirected networks: for each i ∈ {1, 2,…, n}, any eigenvalue of Hermitian normalized Laplacian matrix λ i ∈ [0, 2]. Moreover, we prove some special conditions if 0, or 2 is an eigenvalue of the Hermitian normalized Laplacian matrix L(X). On top of that, we investigate the symmetry of the eigenvalues of L(X)and the edge-version for the eigenvalue interlacing result. Finally we present two expressions for the coefficients of the characteristic polynomial of the Hermitian normalized Laplacian matrix. As an outlook, we sketch some novel and intriguing problems to which our apparatus could generally be applied.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences, Research group: Predictive Society and Data Analytics (PSDA), Guizhou University of Finance and Economics, University of Applied Sciences Upper Austria, Nankai University, Hall in Tyrol, Institute of Biosciences and Medical Technology
Contributors: Yu, G., Dehmer, M., Emmert-Streib, F., Jodlbauer, H.
Number of pages: 10
Pages: 175-184
Publication date: 1 Aug 2019
Peer-reviewed: Yes

Publication information

Journal: Information Sciences
Volume: 495
ISSN (Print): 0020-0255
Ratings: 
  • Scopus rating (2019): CiteScore 11.3 SJR 1.723 SNIP 2.688
Original language: English
ASJC Scopus subject areas: Software, Control and Systems Engineering, Theoretical Computer Science, Computer Science Applications, Information Systems and Management, Artificial Intelligence
Keywords: Characteristic polynomial, Courant–Fischer theorem, Directed networks, Eigenvalue interlacing inequality, Hermitian normalized Laplacian matrix
Source: Scopus
Source ID: 85065248406

Research output: Contribution to journalArticleScientificpeer-review

Looking for a five-legged sheep: Identifying enterprise architects' skills and competencies

Enterprise architecture (EA) is a holistic approach to comprehend the organization's business objectives and processes, data resources, information systems and information technologies. To advance EA activities, organizations need a myriad of different skills and competences both from individual enterprise architects and from architect teams. However, research on these skills and competences is scarce. Not knowing what skills are actually needed might be one of the reasons why public sector EA endeavors have been very problematic. In this paper, we conduct a qualitative survey among enterprise architects themselves to identify which skills they consider essential for EA work. Our results indicate that the range of skills is great, and finding an expert with all appropriate competencies is like looking for a fivelegged sheep.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Industrial and Information Management
Contributors: Ylinen, M., Pekkola, S.
Publication date: 30 May 2018

Host publication information

Title of host publication: Proceedings of the 19th Annual International Conference on Digital Government Research : Governance in the Data Age, DG.O 2018
Publisher: ACM
Article number: a58
ISBN (Electronic): 9781450365260
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Source: Scopus
Source ID: 85049050136

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Majorization-minimization for manifold embedding

Nonlinear dimensionality reduction by manifold embedding has become a popular and powerful approach both for visualization and as preprocessing for predictive tasks, but more efficient optimization algorithms are still crucially needed. Majorization-Minimization (MM) is a promising approach that monotonically decreases the cost function, but it remains unknown how to tightly majorize the manifold embedding objective functions such that the resulting MM algorithms are efficient and robust. We propose a new MM procedure that yields fast MM algorithms for a wide variety of manifold embedding problems. In our majorization step, two parts of the cost function are respectively upper bounded by quadratic and Lipschitz surrogates, and the resulting upper bound can be minimized in closed form. For cost functions amenable to such QL-majorization, the MM yields monotonic improvement and is efficient: In experiments, the newly developed MM algorithms outperformed five state-ofthe-art optimization approaches in manifold embedding tasks.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Research Community on Data-to-Decision (D2D), Aalto University
Contributors: Yang, Z., Peltonen, J., Kaski, S.
Number of pages: 10
Pages: 1088-1097
Publication date: 2015
Peer-reviewed: Yes

Publication information

Journal: Journal of Machine Learning Research
Volume: 38
ISSN (Print): 1532-4435
Ratings: 
  • Scopus rating (2015): CiteScore 4.5 SJR 1.431 SNIP 2.032
Original language: English
ASJC Scopus subject areas: Control and Systems Engineering, Software, Statistics and Probability, Artificial Intelligence
Source: Scopus
Source ID: 84954311496

Research output: Contribution to journalArticleScientificpeer-review

Optimization equivalence of divergences improves neighbor embedding

Visualization methods that arrange data objects in 2D or 3D layouts have followed two main schools, methods oriented for graph layout and methods oriented for vectorial embedding. We show the two previously separate approaches are tied by an optimization equivalence, making it possible to relate methods from the two approaches and to build new methods that take the best of both worlds. In detail, we prove a theorem of optimization equivalences between β- And γ-, as well as α- And Rényi-divergences through a connection scalar. Through the equivalences we represent several nonlinear dimensionality reduction and graph drawing methods in a generalized stochastic neighbor embedding setting, where information divergences are minimized between similarities in input and output spaces, and the optimal connection scalar provides a natural choice for the tradeoff between attractive and repulsive forces. We give two ex-amples of developing new visualization methods through the equivalences: 1) We develop weighted symmetric stochastic neighbor embedding (ws-SNE) from Elastic Embedding and analyze its benefits, good performance for both vectorial and network data; in experiments ws-SNE has good performance across data sets of different types, whereas comparison methods fail for some of the data sets; 2) we develop a γ- divergence version of a Poly Log layout method; the new method is scale invariant in the output space and makes it possible to efficiently use large-scale smoothed neighborhoods.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research Community on Data-to-Decision (D2D), Aalto University, University of Helsinki
Contributors: Yang, Z., Peltonen, J., Kaski, S.
Number of pages: 32
Pages: 1808-1839
Publication date: 2014

Host publication information

Title of host publication: 31st International Conference on Machine Learning, ICML 2014
Volume: 2
Publisher: International Machine Learning Society (IMLS)
ISBN (Electronic): 9781634393973
ASJC Scopus subject areas: Artificial Intelligence, Computer Networks and Communications, Software
Source: Scopus
Source ID: 84919948041

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Peer to Peer Offloading with Delayed Feedback: An Adversary Bandit Approach

Fog computing brings computation and services to the edge of networks enabling real time applications. In order to provide satisfactory quality of experience, the latency of fog networks needs to be minimized. In this paper, we consider a peer computation offloading problem for a fog network with unknown dynamics. Peer competition occurs when different fog nodes offload tasks to the same peer FN. In this paper, the computation offloading problem is modeled as a sequential FN selection problem with delayed feedback. We construct an online learning policy based on the adversary multi-arm bandit framework to deal with peer competition and delayed feedback. Simulation results validate the effectiveness of the proposed policy.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Electrical Engineering, Research group: Wireless Communications and Positioning, Shanghai Advanced Research Institute, Chinese Academy of Sciences, ShanghaiTech University, Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences, Peoples’ Friendship University of Russia
Contributors: Yang, M., Zhu, H., Wang, H., Koucheryavy, Y., Samouylov, K., Qian, H.
Number of pages: 5
Pages: 5035-5039
Publication date: 1 May 2020

Host publication information

Title of host publication: 2020 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2020 - Proceedings
Publisher: IEEE
ISBN (Electronic): 9781509066315

Publication series

Name: ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings
Volume: 2020-May
ISSN (Print): 1520-6149
ASJC Scopus subject areas: Software, Signal Processing, Electrical and Electronic Engineering
Keywords: adversary multi-arm bandit, delayed feed-back, Fog computing, reinforcement learning, task offloading
Source: Scopus
Source ID: 85089215773

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Anthropometric clothing measurements from 3D body scans

We propose a full processing pipeline to acquire anthropometric measurements from 3D measurements. The first stage of our pipeline is a commercial point cloud scanner. In the second stage, a pre-defined body model is fitted to the captured point cloud. We have generated one male and one female model from the SMPL library. The fitting process is based on non-rigid iterative closest point algorithm that minimizes overall energy of point distance and local stiffness energy terms. In the third stage, we measure multiple circumference paths on the fitted model surface and use a nonlinear regressor to provide the final estimates of anthropometric measurements. We scanned 194 male and 181 female subjects, and the proposed pipeline provides mean absolute errors from 2.5 to 16.0 mm depending on the anthropometric measurement.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences, Research group: Vision, NOMO Technologies Ltd
Contributors: Yan, S., Wirta, J., Kämäräinen, J.
Number of pages: 11
Publication date: 2020
Peer-reviewed: Yes

Publication information

Journal: Machine Vision and Applications
Volume: 31
Issue number: 1-2
Article number: 7
ISSN (Print): 0932-8092
Original language: English
ASJC Scopus subject areas: Software, Hardware and Architecture, Computer Vision and Pattern Recognition, Computer Science Applications
Keywords: 3D body model, Anthropometric measurement, Non-rigid ICP
Source: Scopus
Source ID: 85078296322

Research output: Contribution to journalArticleScientificpeer-review

Parameterized scheduling for signal processing systems using topological patterns

In recent work, a graphical modeling construct called "topological patterns" has been shown to enable concise representation and direct analysis of repetitive dataflow graph sub-structures in the context of design methods and tools for digital signal processing systems [1]. In this paper, we present a formal design method for specifying topological patterns and deriving parameterized schedules from such patterns based on a novel schedule model called the scalable schedule tree. The approach represents an important class of parameterized schedule structures in a form that is intuitive for representation and efficient for code generation. We demonstrate our methods for topological pattern representation, scalable schedule tree derivation, and associated dataflow graph code generation using a case study for image processing.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing Research Community (SPRC), University of Maryland, Department of Electrical and Computer Engineering
Contributors: Wu, S., Shen, C. C., Sane, N., Davis, K., Bhattacharyya, S. S.
Number of pages: 4
Pages: 1561-1564
Publication date: 2012

Host publication information

Title of host publication: 2012 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2012 - Proceedings
Article number: 6288190
ISBN (Print): 9781467300469
ASJC Scopus subject areas: Software, Signal Processing, Electrical and Electronic Engineering
Keywords: image registration, scheduling, software tools
Source: Scopus
Source ID: 84867599709

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

A model-based schedule representation for heterogeneous mapping of dataflow graphs

Dataflow-based application specifications are widely used in model-based design methodologies for signal processing systems. In this paper, we develop a new model called the dataflow schedule graph (DSG) for representing a broad class of dataflow graph schedules. The DSG provides a graphical representation of schedules based on dataflow semantics. In conventional approaches, applications are represented using dataflow graphs, whereas schedules for the graphs are represented using specialized notations, such as various kinds of sequences or looping constructs. In contrast, the DSG approach employs dataflow graphs for representing both application models and schedules that are derived from them. Our DSG approach provides a precise, formal framework for unambiguously representing, analyzing, manipulating, and interchanging schedules. We develop detailed formulations of the DSG representation, and present examples and experimental results that demonstrate the utility of DSGs in the context of heterogeneous signal processing system design.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing Research Community (SPRC), University of Maryland, Department of Electrical and Computer Engineering
Contributors: Wu, H. H., Shen, C. C., Sane, N., Plishker, W., Bhattacharyya, S. S.
Number of pages: 12
Pages: 70-81
Publication date: 2011

Host publication information

Title of host publication: 2011 IEEE International Symposium on Parallel and Distributed Processing, Workshops and Phd Forum, IPDPSW 2011
Article number: 6008822
ISBN (Print): 9780769543857
ASJC Scopus subject areas: Computational Theory and Mathematics, Software, Theoretical Computer Science
Keywords: Dataflow graphs, Heterogeneous computing, Models of computation, Scheduling
Source: Scopus
Source ID: 83455253826

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

A design tool for high performance image processing on multicore platforms

Design and implementation of smart vision systems often involve the mapping of complex image processing algorithms into efficient, real-time implementations on multicore platforms. In this paper, we describe a novel design tool that is developed to address this important challenge. A key component of the tool is a new approach to hierarchical dataflow scheduling that integrates a global scheduler and multiple local schedulers. The local schedulers are lightweight modules that work independently. The global scheduler interacts with the local schedulers to optimize overall memory usage and execution time. The proposed design tool is demonstrated through a case study involving an image stitching application for large scale microscopy images.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, University of Maryland, National Institute of Standards and Technology
Contributors: Wu, J., Blattner, T., Keyrouz, W., Bhattacharyya, S. S.
Number of pages: 6
Pages: 1304-1309
Publication date: 19 Apr 2018

Host publication information

Title of host publication: Proceedings of the 2018 Design, Automation and Test in Europe Conference and Exhibition, DATE 2018
Publisher: IEEE
ISBN (Electronic): 9783981926316
ASJC Scopus subject areas: Safety, Risk, Reliability and Quality, Hardware and Architecture, Software, Information Systems and Management
Source: Scopus
Source ID: 85048740891

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Some background on dialogue management and conversational speech for dialogue systems

Several dialogue management (DM) architectures and conversational speech for dialogue systems are presented. Basic types of DM systems include dialogue grammars and frames, plan-based and collaborative systems, and conversational games theory. DM architectures include SmartKom, Trindi, WITAS, CONVERSE, COMIC, agent-based dialogue management, and DM and automatic speech recognition (ASR) language modeling. All data collection tasks should be tailored for the conversational scenario under consideration as each scenario can present different properties. It is shown in the multimodal dialogue system that turn taking can usually be achieved by a fusion of gesture, gaze, and intonation. Intonation within the speech signal informs the dialogue manager when new information is introduced into the current conversation. By placing established emotion detection methods within the recursive nature of conversation we can consider discourse as the exploitation of the shared set of interaction affordances.

General information

Publication status: Published
MoE publication type: A2 Review article in a scientific journal
Organisations: Augmented Human Activities (AHA), University of Oxford, University of Sheffield
Contributors: Wilks, Y., Catizone, R., Worgan, S., Turunen, M.
Number of pages: 12
Pages: 128-139
Publication date: Apr 2011
Peer-reviewed: Yes

Publication information

Journal: Computer Speech and Language
Volume: 25
Issue number: 2
ISSN (Print): 0885-2308
Ratings: 
  • Scopus rating (2011): CiteScore 4.2 SJR 0.586 SNIP 1.9
Original language: English
ASJC Scopus subject areas: Theoretical Computer Science, Software, Human-Computer Interaction
Keywords: Dialogue architectures, Dialogue management, Dialogue systems, Emotion detection, Human-computer interaction
Source: Scopus
Source ID: 78049527943

Research output: Contribution to journalReview ArticleScientificpeer-review

Low-latency Deep Clustering for Speech Separation

This paper proposes a low algorithmic latency adaptation of the deep clustering approach to speaker-independent speech separation. It consists of three parts: a) the usage of long-short-term-memory (LSTM) networks instead of their bidirectional variant used in the original work, b) using a short synthesis window (here 8 ms) required for low-latency operation, and, c) using a buffer in the beginning of audio mixture to estimate cluster centres corresponding to constituent speakers which are then utilized to separate speakers within the rest of the signal. The buffer duration would serve as an initialization phase after which the system is capable of operating with 8 ms algorithmic latency. We evaluate our proposed approach on two-speaker mixtures from Wall Street Journal (WSJ0) corpus. We observe that the use of LSTM yields around one dB lower SDR as compared to the baseline bidirectional LSTM in terms of source to distortion ratio (SDR). Moreover, using an 8 ms synthesis window instead of 32 ms degrades the separation performance by around 2.1 dB as compared to the baseline. Finally, we also report separation performance with different buffer durations noting that separation can be achieved even for buffer duration as low as 300 ms.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Research group: Audio research group - ARG
Contributors: Wang, S., Naithani, G., Virtanen, T.
Number of pages: 5
Pages: 76-80
Publication date: 1 May 2019

Host publication information

Title of host publication: 2019 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2019 - Proceedings
Publisher: IEEE
ISBN (Electronic): 9781479981311
ASJC Scopus subject areas: Software, Signal Processing, Electrical and Electronic Engineering
Keywords: Deep clustering, Low latency, Monaural speech separation

Bibliographical note

int=comp,"Wang, Shanshan"

Source: Scopus
Source ID: 85068960960

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

HTML5-based mobile agents for Web-of-Things

Systems and services utilizing Internet-of-Things can benefit from dynamically updated software in a significant way. In this paper we show how the most advanced variant of moving code, mobile agents, can be used for operating and managing Internet-connected systems composed of gadgets, sensors and actuators. We believe that the use of mobile agents brings several benefits, for example, mobile agents help to reduce the network load, overcome network latency, and encapsulate protocols. In addition, they can perform autonomous tasks that would otherwise require extensive configuration. The need for moving agents is even more significant if the applications and other factors of the over experience should follow the user to new contexts. When multiple agents are used to provide the user with services, some mechanisms to manage the agents are needed. In the context of Internet-of-Things such management should reflect the physical spaces and other relevant contexts. In this paper we describe the technical solutions used in implementation of the mobile agents, describe two proof concepts and we also compare our solution to related work. We also describe our visions of the future work.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Pervasive Computing, Research area: Software engineering
Contributors: Voutilainen, J. P., Mattila, A. L., Systä, K., Mikkonen, T.
Number of pages: 9
Pages: 43-51
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: Informatica
Volume: 40
Issue number: 1
ISSN (Print): 0350-5596
Ratings: 
  • Scopus rating (2016): CiteScore 1.2 SJR 0.136 SNIP 0.461
Original language: English
ASJC Scopus subject areas: Computer Science Applications, Software, Artificial Intelligence, Theoretical Computer Science
Keywords: Html5, Internet-of-things, Javascript, Mobile agents, Web applications, Web-of-things
Source: Scopus
Source ID: 84963719558

Research output: Contribution to journalArticleScientificpeer-review

A Mixed Finite Element Method to Solve the EEG Forward Problem

Finite element methods have been shown to achieve high accuracies in numerically solving the EEG forward problem and they enable the realistic modeling of complex geometries and important conductive features such as anisotropic conductivities. To date, most of the presented approaches rely on the same underlying formulation, the continuous Galerkin (CG)-FEM. In this article, a novel approach to solve the EEG forward problem based on a mixed finite element method (Mixed-FEM) is introduced. To obtain the Mixed-FEM formulation, the electric current is introduced as an additional unknown besides the electric potential. As a consequence of this derivation, the Mixed-FEM is, by construction, current preserving, in contrast to the CG-FEM. Consequently, a higher simulation accuracy can be achieved in certain scenarios, e.g., when the diameter of thin insulating structures, such as the skull, is in the range of the mesh resolution. A theoretical derivation of the Mixed-FEM approach for EEG forward simulations is presented, and the algorithms implemented for solving the resulting equation systems are described. Subsequently, first evaluations in both sphere and realistic head models are presented, and the results are compared to previously introduced CG-FEM approaches. Additional visualizations are shown to illustrate the current preserving property of the Mixed-FEM. Based on these results, it is concluded that the newly presented Mixed-FEM can at least complement and in some scenarios even outperform the established CG-FEM approaches, which motivates a further evaluation of the Mixed-FEM for applications in bioelectromagnetism.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Mathematics, Research group: Inverse Problems, University of Utah, Cluster of Excellence EXC, University of Münster
Contributors: Vorwerk, J., Engwer, C., Pursiainen, S., Wolters, C. H.
Number of pages: 12
Pages: 930-941
Publication date: 1 Apr 2017
Peer-reviewed: Yes

Publication information

Journal: IEEE Transactions on Medical Imaging
Volume: 36
Issue number: 4
Article number: 7731161
ISSN (Print): 0278-0062
Ratings: 
  • Scopus rating (2017): CiteScore 9.3 SJR 1.895 SNIP 2.904
Original language: English
ASJC Scopus subject areas: Software, Radiological and Ultrasound Technology, Computer Science Applications, Electrical and Electronic Engineering
Keywords: EEG, forward problem, mixed finite element method, realistic head modeling, source analysis
Source: Scopus
Source ID: 85017598893

Research output: Contribution to journalArticleScientificpeer-review

Combined local and global image enhancement algorithm

We present a new image enhancement algorithm based on combined local and global image processing. The basic idea is to apply α-rooting image enhancement approach for different image blocks. For this purpose, we split image in moving windows on disjoint blocks with different size (8 by 8, 16 by 16, 32 by 32 and, i.e.). The parameter alfa for every block driven through optimization of measure of enhancement (EME). The resulting image is a weighted mean of all processing blocks. This strategy for image enhancement allows getting more contrast image with the following properties: irregular lighting and brightness gradient. Some experimental results are presented to illustrate the performance of the proposed algorithm.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing, Don State Technical University, College of Staten Island
Contributors: Voronin, V., Semenishchev, E., Ponomarenko, M., Agaian, S.
Publication date: 2018

Host publication information

Title of host publication: Electronic Imaging : Image Processing: Algorithms and Systems XVI
Publisher: Society for Imaging Science and Technology
ASJC Scopus subject areas: Computer Graphics and Computer-Aided Design, Computer Science Applications, Human-Computer Interaction, Software, Electrical and Electronic Engineering, Atomic and Molecular Physics, and Optics

Bibliographical note

jufoid=84313

Source: Scopus
Source ID: 85052861928

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

On continuous deployment maturity in customer projects

The practice of making new software available to end users as soon as it gets implemented is becoming commonplace. This paper investigates a set of projects and their development practices in a mid-sized Finnish software company Solita Ltd. to understand how continuous deployment practices are applied in development teams. This was done by establishing a maturity scale and using it to survey the teams. In addition, we interviewed members of selected teams to understand why a particular level of maturity is desirable for a project, and to reveal the issues that impact team's ability to improve. We found that while the team, the customer, and the product all benefit from mature development practices associated with continuous deployment, some obstacles can be solved only by changing the organizational modus operandi.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Research area: Software engineering, Solita Ltd., University of Central Lancashire, University of Helsinki
Contributors: Virtanen, A., Kuusinen, K., Leppänen, M., Luoto, A., Kilamo, T., Mikkonen, T.
Number of pages: 8
Pages: 1205-1212
Publication date: 3 Apr 2017

Host publication information

Title of host publication: 32nd Annual ACM Symposium on Applied Computing, SAC 2017
Publisher: ACM
ISBN (Electronic): 9781450344869
ASJC Scopus subject areas: Software
Keywords: Agile, Continuous delivery, DevOps, Lean software development, Maturity model, Systems thinking

Bibliographical note

EXT="Mikkonen, Tommi"
EXT="Virtanen, Antti"
EXT="Kuusinen, Kati"

Source: Scopus
Source ID: 85020898562

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Low latency edge rendering scheme for interactive 360 degree virtual reality gaming

This paper describes the core functionality and a proof-of-concept demonstration setup for remote 360 degree stereo virtual reality (VR) gaming. In this end-to-end scheme, the execution of a VR game is off-loaded from an end user device to a cloud edge server in which the executed game is rendered based on user's field of view (FoV) and control actions. Headset and controller feedback is transmitted over the network to the server from which the rendered views of the game are streamed to a user in real-time as encoded HEVC video frames. This approach saves energy and computation load of the end terminals by making use of the latest advancements in network connection speed and quality. In the showcased demonstration, a VR game is run in Unity on a laptop powered by i7 7820HK processor and GTX 1070 GPU. The 360 degree spherical view of the game is rendered and converted to a rectangular frame using equirectangular projection (ERP). The ERP video is sliced vertically and only the FoV is encoded with Kvazaar HEVC encoder in real time and sent over the network in UDP packets. Another laptop is used for playback with a HTC Vive VR headset. Our system can reach an end-to-end latency of 30 ms and bit rate of 20 Mbps for stereo 1080p30 format.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Datacenter Infrastructure Modules, Nokia Technologies
Contributors: Viitanen, M., Vanne, J., Hämäläinen, T. D., Kulmala, A.
Number of pages: 4
Pages: 1557-1560
Publication date: 19 Jul 2018

Host publication information

Title of host publication: Proceedings - 2018 IEEE 38th International Conference on Distributed Computing Systems, ICDCS 2018
Publisher: IEEE
ISBN (Electronic): 9781538668719
ASJC Scopus subject areas: Software, Hardware and Architecture, Computer Networks and Communications
Keywords: 360 degree video, Edge computing, High Efficiency Video Coding (HEVC), Video coding, Virtual reality (VR)

Bibliographical note

jufoid=58061e

Source: Scopus
Source ID: 85050973480

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Novel pairwise coupled kinematic solution for algebraic angular acceleration estimation of serial link manipulators

We consider low-noise angular acceleration estimation for multi-axis robotic manipulators. The proposed model uses pairwise coupled inertial measurements across a section of the kinematic chain, which is reduced to a single rigid body. Experimental validation is built upon compact low-power micro-electro-mechanical (MEMS) components, installed on a full-scale heavy-duty mobile manipulator. While the model itself has a built-in mechanism for common-mode disturbance rejection, an adaptive transversal filter is devised for a further improvement. The results indicate a 40-80 fold suppression of high-frequency perturbations with respect to a baseline motion derivative, the discrete difference. As inertial sensors require no mechanical contact to rotating axes and the number of parameters is kept low, the model is easily applicable to motion control feedback of typical heavy-duty manipulators.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Signal Processing, Research group: MMDM, Department of Intelligent Hydraulics and Automation, Research group: Mobile manipulation, Research area: Information Technology for Biology and Health, Research area: Intelligence in Machines, Research area: Signal and Information Processing, Signal Processing Research Community (SPRC)
Contributors: Vihonen, J., Honkakorpi, J., Mattila, J., Visa, A.
Number of pages: 6
Pages: 809-814
Publication date: 29 Jun 2015

Host publication information

Title of host publication: 2015 IEEE International Conference on Robotics and Automation (ICRA)
Publisher: Institute of Electrical and Electronics Engineers IEEE
ISBN (Print): 978-1-4799-6923-4
ASJC Scopus subject areas: Software, Artificial Intelligence, Control and Systems Engineering, Electrical and Electronic Engineering

Bibliographical note

ORG=sgn,0.5
ORG=iha,0.5

Source: Scopus
Source ID: 84938217097

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

PaaSword: A holistic data privacy and security by design framework for cloud services

The valuable transformation of organizations that adopt cloud computing is indisputably accompanied by a number of security threats that should be considered. In this paper, we outline significant security challenges presented when migrating to a cloud environment and propose PaaSword-a novel holistic, data privacy and security by design, framework that aspires to alleviate them. The envisaged framework intends to maximize and fortify the trust of individual, professional and corporate users to cloud services. Specifically, PaaSword involves a context-aware security model, the necessary policies enforcement and governance mechanisms along with a physical distribution, encryption and query middleware, aimed at facilitating the implementation of secure and transparent cloud-based applications.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: National Technical University of Athens, Security Lab, SICS, Ubitech Ltd., Karlsruhe Institute of Technology, Insitute for Technical Physics, Germany, CAS Software AG, South East European Research Centre
Contributors: Verginadis, Y., Michalas, A., Gouvas, P., Schiefer, G., Hübsch, G., Paraskakis, I.
Number of pages: 8
Pages: 206-213
Publication date: 1 Jan 2015

Host publication information

Title of host publication: CLOSER 2015 - 5th International Conference on Cloud Computing and Services Science, Proceedings
Publisher: SCITEPRESS
ISBN (Electronic): 9789897581045
ASJC Scopus subject areas: Software
Keywords: Cloud Computing, Context-aware Security, Data Privacy, Security by Design, Symmetric Searchable Encryption
Source: Scopus
Source ID: 84969792485

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Emotional Reactions to Point-Light Display Animations

Emotional reactions to basic, artificial, yet carefully controllable point-light displays (PLDs) were investigated with ratings of valence, arousal, approachability and dominance. PLDs were varied by movement location (upper and lower) and intensity (10°, 20° and 30° angular change) for angular upward and downward movements. Half of participants (N =28) were told that PLDs were related to face while to other half nothing was hinted. Results showed that 20° and 30° angle lower location upward movements were rated as significantly more pleasant, relaxing and approachable than corresponding upper location downward movements. Informed participants rated 20° and 30° angle lower movements as significantly more controllable than corresponding upper movements. Results are important from many perspectives, like for understanding human perceptual mechanisms. When using PLDs only a small amount of information needs to be transmitted. This enables low bandwidth requirements. As PLD visualizations are simple, there is no need for high-definition displays.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Automation Science and Engineering, Nokia
Contributors: Venesvirta, H., Surakka, V., Gizatdinova, Y., Lylykangas, J., Špakov, O., Verho, J., Vetek, A., Lekkala, J.
Number of pages: 11
Pages: 521-531
Publication date: 16 Jun 2016
Peer-reviewed: Yes

Publication information

Journal: Interacting with Computers
Volume: 28
Issue number: 4
ISSN (Print): 0953-5438
Ratings: 
  • Scopus rating (2016): CiteScore 3.5 SJR 0.374 SNIP 1.128
Original language: English
ASJC Scopus subject areas: Human-Computer Interaction, Software
Keywords: biological movement, emotions, face perception, information visualization, point-light displays, psychology
Source: Scopus
Source ID: 84976499522

Research output: Contribution to journalArticleScientificpeer-review

Guidelines for development and evaluation of usage data analytics tools for human-machine interactions with industrial manufacturing systems

We present the lessons learned during the development and evaluation process for UX-sensors, a visual data analytics tool for inspecting logged usage data from flexible manufacturing systems (FMS). Based on the experiences during a collaborative development process with practitioners from one FMS supplier company, we propose guidelines to support other developers of visual data analytics tools for usage data logging in context of complex industrial systems. For instance, involving stakeholders with different roles can help to identify user requirements and generate valuable development ideas. Tool developers should confirm early access to real usage data from customers' systems and familiarize themselves with the log data structure. We argue that combining expert evaluations with field study methods can provide a more diverse set of usability issues to address. For future research, we encourage studies on insights emerging from usage data analytics and their impact on the viewpoints of the supplier and customer.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Research area: User experience, University of Wisconsin-Stevens Point, Fastems
Contributors: Varsaluoma, J., Väätäjä, H., Heimonen, T., Tiitinen, K., Hakulinen, J., Turunen, M., Nieminen, H.
Number of pages: 10
Pages: 172-181
Publication date: 10 Oct 2018

Host publication information

Title of host publication: Mindtrek 2018 - Proceedings of the 22nd International Academic Mindtrek Conference
Publisher: ACM
ISBN (Electronic): 9781450365895
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software

Bibliographical note

EXT="Nieminen, Harri"

Source: Scopus
Source ID: 85056717713

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Validating effectiveness of safety requirements' compliance evaluation in process assessments

Safety is the primary concern when developing systems containing software in the nuclear power domain. Process assessments are used to ensure quality of the development processes for safety-critical systems. Regulators of the nuclear power industry have increased requirements concerning the systems development processes. Now, process assessments are integrated in the qualification of the systems and are expected to provide information not only based on the assessment model but also about the domain-specific requirements. Therefore, a specific activity, compliance evaluation, was inserted into the assessment process to provide detailed information that supports analysis of the compliance to the domain standards. Compliance evaluation utilizes assessment findings to create evidence of the relevant domain-specific requirements. The main purpose of this study is to validate effectiveness of compliance evaluation by analyzing assessment findings and their relation to the requirements of a safety-critical domain. The analysis is based on representing the data in compliance evaluation reports as binary relations. The results of this analysis indicate that process assessment findings are also relevant when evaluating compliance to other sets of requirements. The results can significantly support the trustworthiness of the process assessment method and ensure effective use of process assessments.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences, Research group: Software Engineering and Intelligent Systems, Research group: Data-analytics and Optimization, Finnish Software Measurement Association
Contributors: Varkoi, T., Mäkinen, T., Cameron, F., Nevalainen, R.
Number of pages: 16
Publication date: 2020
Peer-reviewed: Yes
Early online date: 2019

Publication information

Journal: Journal of Software: Evolution and Process
Volume: 32
Issue number: 3
Article number: e2177
ISSN (Print): 2047-7473
Original language: English
ASJC Scopus subject areas: Software
Keywords: Nuclear SPICE, process assessment, safety, systems engineering

Bibliographical note

EXT="Varkoi, Timo"
EXT="Nevalainen, Risto"

Source: Scopus
Source ID: 85080987236

Research output: Contribution to journalArticleScientificpeer-review

Ripple thermostat: Affecting the emotional experience through interactive force feedback and shape change

Force feedback and shape change are modalities with a growing application potential beyond the more traditional GUIs. We present two studies that explored the effect of these modalities on the emotional experience when interacting with an intelligent thermostat. The first study compared visual feedback, force feedback, and a combination of force feedback and shape change. Results indicate that force feedback correlates to experienced dominance during interaction, while shape change mainly affects experienced arousal. The second study explored how force feedback and shape change could communicate affective meaning during interaction with the thermostat through a co-design study. Participants designed the thermostat behavior for three scenarios supporting energy savings. Results suggest that despite their abstractness, force feedback and shape change convey affective meaning during the user-system dialogue. The findings contribute to the design of intelligible and intuitive feedback.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Aarhus Universitet, Eindhoven University of Technology, Vincit
Contributors: Van Oosterhout, A., Alonso, M. B., Jumisko-Pyykkö, S.
Publication date: 20 Apr 2018

Host publication information

Title of host publication: Proceedings of the 2018 CHI Conference on Human Factors in Computing Systems
Publisher: ACM
Article number: 655
ISBN (Electronic): 9781450356206
ASJC Scopus subject areas: Human-Computer Interaction, Computer Graphics and Computer-Aided Design, Software
Keywords: Actuated interfaces, Affective computing, Haptic force feedback, Shape-changing interfaces
Source: Scopus
Source ID: 85046938728

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Mixed-integer linear programming approach for global discrete sizing optimization of frame structures

This paper focuses on discrete sizing optimization of frame structures using commercial profile catalogs. The optimization problem is formulated as a mixed-integer linear programming (MILP) problem by including the equations of structural analysis as constraints. The internal forces of the members are taken as continuous state variables. Binary variables are used for choosing the member profiles from a catalog. Both the displacement and stress constraints are formulated such that for each member limit values can be imposed at predefined locations along the member. A valuable feature of the formulation, lacking in most contemporary approaches, is that global optimality of the solution is guaranteed by solving the MILP using branch-and-bound techniques. The method is applied to three design problems: a portal frame, a two-story frame with three load cases and a multiple-bay multiple-story frame. Performance profiles are determined to compare the MILP reformulation method with a genetic algorithm.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Civil Engineering, KU Leuven
Contributors: van Mellaert, R., Mela, K., Tiainen, T., Heinisuo, M., Lombaert, G., Schevenels, M.
Number of pages: 15
Pages: 579–593
Publication date: 2018
Peer-reviewed: Yes

Publication information

Journal: Structural and Multidisciplinary Optimization
Volume: 57
Issue number: 2
ISSN (Print): 1615-147X
Ratings: 
  • Scopus rating (2018): CiteScore 5.1 SJR 1.835 SNIP 1.887
Original language: English
ASJC Scopus subject areas: Control and Systems Engineering, Software, Computer Science Applications, Computer Graphics and Computer-Aided Design, Control and Optimization
Keywords: Discrete optimization, Frame structures, Global optimization, Mixed-integer linear programming, Sizing optimization
Source: Scopus
Source ID: 85026724545

Research output: Contribution to journalArticleScientificpeer-review

On constructibility and unconstructibility of LTS operators from other LTS operators

An LTS operator can be constructed from a set of LTS operators up to an equivalence if and only if there is an LTS expression that only contains operators from the set and whose result is equivalent to the result of the operator. In this publication this idea is made precise in the context where each LTS has an alphabet of its own and the operators may depend on the alphabets. Then the extent to which LTS operators are constructible is studied. Most, if not all, established LTS operators have the property that each trace of the result arises from the execution of no more than one trace of each of its argument LTSs, and similarly for infinite traces. All LTS operators that have this property and satisfy some other rather weak regularity properties can be constructed from parallel composition and hiding up to the equivalence that compares the alphabets, traces, and infinite traces of the LTSs. Furthermore, a collection of other miscellaneous constructibility and unconstructibility results is presented.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Mathematics, Regulation of learning and active learning methods (REALMEE)
Contributors: Valmari, A.
Number of pages: 28
Pages: 207-234
Publication date: 2015
Peer-reviewed: Yes

Publication information

Journal: Acta Informatica
Volume: 52
Issue number: 2-3
ISSN (Print): 0001-5903
Ratings: 
  • Scopus rating (2015): CiteScore 1.7 SJR 0.421 SNIP 0.736
Original language: English
ASJC Scopus subject areas: Computer Networks and Communications, Information Systems, Software
Electronic versions: 
Source: Scopus
Source ID: 84925463574

Research output: Contribution to journalArticleScientificpeer-review

A State Space Tool for Concurrent System Models Expressed In C++

This publication introduces a state space exploration tool that is based on representing the model under verification as a piece of C++ code that obeys certain conventions. This approach facilitates experimenting with many kinds of modelling ideas. On the other hand, the use of stubborn sets and symmetries requires that either the modeller or a preprocessor tool analyses the model at a syntactic level and expresses stubborn set obligation rules and the symmetry mapping as suitable C++ functions. The tool supports the detection of illegal deadlocks, safety errors, and may progress errors. It also partially supports the detection of must progress errors.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Mathematics, Research group: MAT Computer Science and Applied Logics, Regulation of learning and active learning methods (REALMEE)
Contributors: Valmari, A.
Number of pages: 15
Pages: 91-105
Publication date: 14 Dec 2015

Host publication information

Title of host publication: SPLST 2015 Symposium on Programming Languages and Software Tools : Proceedings of the 14th Symposium on Programming Languages and Software Tools (SPLST'15) Tampere, Finland, Oct 9-10, 2015
Volume: 1525
Publisher: CEUR-WS.org
Editors: Nummenmaa, J., Sievi-Korte, O., Mäkinen, E.
Article number: 7

Publication series

Name: CEUR Workshop Proceedings
Volume: 1525
ISSN (Electronic): 1613-0073
ASJC Scopus subject areas: Software
Keywords: model checking; stubborn sets; symmetries; safety; progress

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Stop it, and be stubborn!

This publication discusses how automatic verification of concurrent systems can be made more efficient by focusing on always may-terminating systems. First, making a system always may-terminating is a method formeeting a modelling need that exists independently of this publication. It is illustrated that without doing so, non-progress errors may be lost. Second, state explosion is often alleviated with stubborn, ample, and persistent set methods. They use expensive cycle or terminal strong component conditions in many cases. It is proven that for many important classes of properties, if the systems are always may-terminating, then these conditions can be left out.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Mathematics, Research group: MAT Computer Science and Applied Logics
Contributors: Valmari, A.
Publication date: 1 Jan 2017
Peer-reviewed: Yes

Publication information

Journal: ACM Transactions on Embedded Computing Systems
Volume: 16
Issue number: 2
Article number: 46
ISSN (Print): 1539-9087
Ratings: 
  • Scopus rating (2017): CiteScore 2.5 SJR 0.32 SNIP 1.093
Original language: English
ASJC Scopus subject areas: Software, Hardware and Architecture
Keywords: Ignoring problem, Safety/progress/liveness properties, Stubborn set/ample set/persistent set/partial order methods
Source: Scopus
Source ID: 85011350059

Research output: Contribution to journalArticleScientificpeer-review

Fair testing and stubborn sets

Partial order methods alleviate state explosion by considering only a subset of actions in each constructed state. The choice of the subset depends on the properties that the method promises to preserve. Many methods have been developed ranging from deadlock-preserving to CTL(Formula presented.)-preserving and divergence-sensitive branching bisimilarity preserving. The less the method preserves, the smaller state spaces it constructs. Fair testing equivalence unifies deadlocks with livelocks that cannot be exited and ignores the other livelocks. It is the weakest congruence that preserves whether or not the system may enter a livelock that it cannot leave. We prove that a method that was designed for trace equivalence also preserves fair testing equivalence. We demonstrate its effectiveness on a protocol with a connection and data transfer phase. This is the first practical partial order method that deals with a practical fairness assumption.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Mathematics, University of Augsburg
Contributors: Valmari, A., Vogler, W.
Number of pages: 22
Pages: 589-610
Publication date: 2018
Peer-reviewed: Yes
Early online date: 11 Dec 2017

Publication information

Journal: International Journal on Software Tools for Technology Transfer
ISSN (Print): 1433-2779
Ratings: 
  • Scopus rating (2018): CiteScore 4.8 SJR 0.472 SNIP 1.693
Original language: English
ASJC Scopus subject areas: Software, Information Systems
Keywords: Fair testing equivalence, Fairness, Partial order methods, Progress, Stubborn sets
Electronic versions: 
URLs: 
Source: Scopus
Source ID: 85037686390

Research output: Contribution to journalArticleScientificpeer-review

Optimizing gaze direction in a visual navigation task

Navigation in an unknown environment consists of multiple separable subtasks, such as collecting information about the surroundings and navigating to the current goal. In the case of pure visual navigation, all these subtasks need to utilize the same vision system, and therefore a way to optimally control the direction of focus is needed. We present a case study, where we model the active sensing problem of directing the gaze of a mobile robot with three machine vision cameras as a partially observable Markov decision process (POMDP) using a mutual information (MI) based reward function. The key aspect of the solution is that the cameras are dynamically used either in monocular or stereo configuration. The benefits of using the proposed active sensing implementation are demonstrated with simulations and experiments on a real robot.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Automation Science and Engineering, Research area: Dynamic Systems
Contributors: Välimäki, T., Ritala, R.
Number of pages: 6
Pages: 1427-1432
Publication date: 8 Jun 2016

Host publication information

Title of host publication: 2016 IEEE International Conference on Robotics and Automation (ICRA)
Publisher: IEEE
ISBN (Print): 9781467380263
ASJC Scopus subject areas: Software, Artificial Intelligence, Control and Systems Engineering, Electrical and Electronic Engineering
Source: Scopus
Source ID: 84977478616

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

A convolutional neural network approach for acoustic scene classification

This paper presents a novel application of convolutional neural networks (CNNs) for the task of acoustic scene classification (ASC). We here propose the use of a CNN trained to classify short sequences of audio, represented by their log-mel spectrogram. We also introduce a training method that can be used under particular circumstances in order to make full use of small datasets. The proposed system is tested and evaluated on three different ASC datasets and compared to other state-of-the-art systems which competed in the 'Detection and Classification of Acoustic Scenes and Events' (DCASE) challenges held in 20161 and 2013. The best accuracy scores obtained by our system on the DCASE 2016 datasets are 79.0% (development) and 86.2% (evaluation), which constitute a 6.4% and 9% improvements with respect to the baseline system. Finally, when tested on the DCASE 2013 evaluation dataset, the proposed system manages to reach a 77.0% accuracy, improving by 1% the challenge winner's score.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing, Research group: Audio research group - ARG, Department of Information Engineering
Contributors: Valenti, M., Squartini, S., Diment, A., Parascandolo, G., Virtanen, T.
Number of pages: 8
Pages: 1547-1554
Publication date: 30 Jun 2017

Host publication information

Title of host publication: 2017 International Joint Conference on Neural Networks, IJCNN 2017
Publisher: IEEE
ISBN (Electronic): 9781509061815
ASJC Scopus subject areas: Software, Artificial Intelligence
Electronic versions: 

Bibliographical note

jufoid=58177

Source: Scopus
Source ID: 85031008536

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Feasibility of FPGA accelerated IPsec on cloud

Hardware acceleration for famous VPN solution, IPsec, has been widely researched already. Still it is not fully covered and the increasing latency, throughput, and feature requirements need further evaluation. We propose an IPsec accelerator architecture in an FPGA and explain the details that need to be considered for a production ready design. This research considers the IPsec packet processing without IKE to be offloaded on an FPGA in an SDN network. Related work performance rates in 64 byte packet size for throughput is 1–2 Gbps with 0.2 ms latency in software, and 1–4 Gbps with unknown latencies for hardware solutions. Our proposed architecture is capable to host 1000 concurrent tunnels and have 10 Gbps throughput with only 10 µs latency in our test network. Therefore the proposed design is efficient even with voice or video encryption. The architecture is especially designed for data centers and locations with vast number of concurrent IPsec tunnels. The research confirms that FPGA based hardware acceleration increases performance and is feasible to integrate with the other server infrastructure.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences, Research area: Information security, Baseband ASIC R&D, Nokia Siemens Networks
Contributors: Vajaranta, M., Oinonen, A., Hämäläinen, T. D., Viitamäki, V., Markunmäki, J., Kulmala, A.
Publication date: 1 Nov 2019
Peer-reviewed: Yes

Publication information

Journal: Microprocessors and Microsystems
Volume: 71
Article number: 102861
ISSN (Print): 0141-9331
Ratings: 
  • Scopus rating (2019): CiteScore 3 SJR 0.303 SNIP 0.879
Original language: English
ASJC Scopus subject areas: Software, Hardware and Architecture, Computer Networks and Communications, Artificial Intelligence
Keywords: Accelerator, IPsec, Offloading, SDN

Bibliographical note

EXT="Viitamäki, Vili"
EXT="Kulmala, Ari"

Source: Scopus
Source ID: 85070320729

Research output: Contribution to journalArticleScientificpeer-review

Integrated controller for an over-constrained cable driven parallel manipulator: KNTU CDRPM

This paper presents an approach to the control of the KNTU CDRPM using an integrated control scheme. The goal in this approach is achieving accurate trajectory tracking while assuring positive tension in the cables. By the proposed controller, the inherent nonlinear behavior of the cable and the target tracking errors are simultaneously compensated. In this paper asymptotic stability analysis of the close loop system is studied in detail. Moreover, it is shown that the integrated control strategy reduces the tracking error by 80% compared to that of a single loop controller in the considered manipulator. The closed-loop performance of the control topology is analyzed by a simulation study that is performed on the manipulator. The simulation study verifies that the proposed controller is not only promising to be implemented on the KNTU CDRPM, but also being suitable for other cable driven manipulators.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: K. N. Toosi University of Technology, Advanced Robotics and Automated Systems (ARAS)
Contributors: Vafaei, A., Aref, M. M., Taghirad, H. D.
Number of pages: 6
Pages: 650-655
Publication date: 2010

Host publication information

Title of host publication: Proceedings - IEEE International Conference on Robotics and Automation
Article number: 5509991
ISBN (Print): 9781424450381
ASJC Scopus subject areas: Software, Artificial Intelligence, Control and Systems Engineering, Electrical and Electronic Engineering
Source: Scopus
Source ID: 77955796077

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Towards Efficient Code Generation for Exposed Datapath Architectures

Coarse-grained reconfigurable architectures and other exposed datapath architectures such as transport-triggered architectures come with a high energy efficiency promise for accelerating data oriented workloads. Their main drawback results from the push of complexity from the architecture to the programmer; compiler techniques that allow starting from a higher-level programming language and generate code efficiently to such architectures robustly is still an open research area. In this article we survey the known main sources of challenges and outline a generic processor architecture template that covers the most common architecture variations along with a proposal for a common code generation framework for such challenging architectures.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Eindhoven University of Technology
Contributors: Vadivel, K., Jordans, R., Stujik, S., Corporaal, H., Jääskeläinen, P., Kultala, H.
Number of pages: 4
Pages: 86-89
Publication date: 27 May 2019

Host publication information

Title of host publication: Proceedings of the 22nd International Workshop on Software and Compilers for Embedded Systems, SCOPES 2019
Publisher: ACM
Editor: Stuijk, S.
ISBN (Electronic): 9781450367622
ASJC Scopus subject areas: Hardware and Architecture, Software
Keywords: CGRA, code generation, energy efficiency, reconfigurable architectures, scheduling, TTA
Source: Scopus
Source ID: 85066039585

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Briefing news reporting with mobile assignments - Perceptions, needs and challenges

Mobile handheld devices are an increasing part of everyday fieldwork of news professionals. Mobile assignments delivered to mobile journalists' smartphones are one potential future development step. We present findings on using mobile assignments from two exploratory user studies in which smartphones were used as news reporting tools. Mobile assignments were perceived as handy for fast reporting situations and simple stories but challenging in case of more complex tasks. Structured information content of assignments, process phase based information and supporting situation and activity awareness would support the work of both editorial staff and mobile journalists. The locationing of reporters for sending location-based assignments was found acceptable for coordinating the work although some privacy concerns were expressed. The findings provide new information on using mobile assignments in work where carrying out tasks involves creativity and the tasks may be complex, not strictly limited or they may not have clear completion criteria. © 2012 ACM.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research area: User experience, Department of Software Systems, Augmented Human Activities (AHA), University of Central Lancashire
Contributors: Väätäjä, H., Egglestone, P.
Number of pages: 10
Pages: 485-494
Publication date: 2012

Host publication information

Title of host publication: Proceedings of the ACM 2012 conference on Computer Supported Cooperative Work CSCW'12 Seattle, WA, USA, February 11-15, 2012
Place of publication: New York, NY
Publisher: ACM
ISBN (Print): 9781450310864

Publication series

Name: ACM Conference on Computer Supported Cooperative Work
ASJC Scopus subject areas: Human-Computer Interaction, Software, Computer Networks and Communications
Keywords: assignment, crowdsourcing, journalist, location, mobile, news, privacy., professional, smartphone, task, work

Bibliographical note

ei ut-numeroa 21.9.2013<br/>Contribution: organisation=ohj,FACT1=1<br/>Publisher name: ACM

Source: researchoutputwizard
Source ID: 5484

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Software Startups - A Research Agenda

Software startup companies develop innovative, software-intensive products within limited time frames and with few resources, searching for sustainable and scalable business models. Software startups are quite distinct from traditional mature software companies, but also from micro-, small-, and medium-sized enterprises, introducing new challenges relevant for software engineering research. This paper's research agenda focuses on software engineering in startups, identifying, in particular, 70+ research questions in the areas of supporting startup engineering activities, startup evolution models and patterns, ecosystems and innovation hubs, human aspects in software startups, applying startup concepts in non-startup environments, and methodologies and theories for startup research. We connect and motivate this research agenda with past studies in software startup research, while pointing out possible future directions. While all authors of this research agenda have their main background in Software Engineering or Computer Science, their interest in software startups broadens the perspective to the challenges, but also to the opportunities that emerge from multi-disciplinary research. Our audience is therefore primarily software engineering researchers, even though we aim at stimulating collaborations and research that crosses disciplinary boundaries. We believe that with this research agenda we cover a wide spectrum of the software startup industry current needs.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Pervasive Computing, Research area: User experience, Blekinge Institute of Technology, Norwegian Univ. of Sci. and Technol., Free University of Bolzano-Bozen, SICS, Lake Constance University, Natl. University of Ireland, Galway, Universidad Politecnica de Madrid, Department of Applied Physics, University of Cagliari, National University of Ireland Maynooth, Univ of Oulu, Hochschule Konstanz
Contributors: Unterkalmsteiner, M., Abrahamsson, P., Wang, X. F., Nguyen-Duc, A., Shah, S., Bajwa, S. S., Baltes, G. H., Conboy, K., Cullina, E., Dennehy, D., Edison, H., Fernandez-Sanchez, C., Garbajosa, J., Gorschek, T., Klotins, E., Hokkanen, L., Kon, F., Lunesu, I., Marchesi, M., Morgan, L., Oivo, M., Selig, C., Seppänen, P., Sweetman, R., Tyrväinen, P., Ungerer, C., Yagüe, A.
Number of pages: 35
Pages: 89-123
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: e-Informatica Software Engineering Journal
Volume: 10
Issue number: 1
ISSN (Print): 1897-7979
Ratings: 
  • Scopus rating (2016): CiteScore 1.3 SJR 0.136 SNIP 0.743
Original language: English
ASJC Scopus subject areas: Software
Keywords: Research agenda, Software startup, Software-intensive systems

Bibliographical note

EXT="Shah, Syed"

Source: Scopus
Source ID: 84994056890

Research output: Contribution to journalArticleScientificpeer-review

Multimodal and mobile conversational Health and Fitness Companions

Multimodal conversational spoken dialogues using physical and virtual agents provide a potential interface to motivate and support users in the domain of health and fitness. This paper describes how such multimodal conversational Companions can be implemented to support their owners in various pervasive and mobile settings. We present concrete system architectures, virtual, physical and mobile multimodal interfaces, and interaction management techniques for such Companions. In particular how knowledge representation and separation of low-level interaction modelling from high-level reasoning at the domain level makes it possible to implement distributed, but still coherent, interaction with Companions. The distribution is enabled by using a dialogue plan to communicate information from domain level planner to dialogue management and from there to a separate mobile interface. The model enables each part of the system to handle the same information from its own perspective without containing overlapping logic, and makes it possible to separate task-specific and conversational dialogue management from each other. In addition to technical descriptions, results from the first evaluations of the Companions interfaces are presented.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Augmented Human Activities (AHA), SICS, Norwegian Univ. of Sci. and Technol., Telefonica, School of Computing Teesside University Middlesbrough
Contributors: Turunen, M., Hakulinen, J., Ståhl, O., Gambäck, B., Hansen, P., Rodríguez Gancedo, M. C., De La Cámara, R. S., Smith, C., Charlton, D., Cavazza, M.
Number of pages: 18
Pages: 192-209
Publication date: Apr 2011
Peer-reviewed: Yes

Publication information

Journal: Computer Speech and Language
Volume: 25
Issue number: 2
ISSN (Print): 0885-2308
Ratings: 
  • Scopus rating (2011): CiteScore 4.2 SJR 0.586 SNIP 1.9
Original language: English
ASJC Scopus subject areas: Theoretical Computer Science, Software, Human-Computer Interaction
Keywords: Cognitive modelling, Companions, Conversational spoken dialogue systems, Dialogue management, Embodied conversational agents, Mobile interfaces
Source: Scopus
Source ID: 78049527811

Research output: Contribution to journalArticleScientificpeer-review

Necessary and sufficient conditions for the existence of solution of generalized fuzzy relation equations A ⇔X = B

In 2013 Li and Jin studied a particular type of fuzzy relational equations on finite sets, where the introduced min-bi-implication composition is based on Łukasiewicz equivalence. In this paper such fuzzy relation equations are studied on a more general level, namely complete residuated lattice valued fuzzy relation equations of type ⋀y∈Y(A(x,y)↔X(y)=B(x) are analyzed, and the existence of solutions S is studied. First a necessary condition for the existence of solution is established, then conditions for lower and upper limits of solutions are given, and finally sufficient conditions for the existence of the smallest and largest solutions, respectively, are characterized. If such general or global solutions do not exist, there might still be partial or point wise solutions; this is a novel way to study fuzzy relation equations. Such point wise solutions are studied on Łukasiewicz, Product and Gödel t-norm based residuated lattices on the real unit interval.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences, Research group: Computer Science and Applied Logics
Contributors: Turunen, E.
Number of pages: 7
Pages: 351-357
Publication date: 1 Oct 2020
Peer-reviewed: Yes

Publication information

Journal: Information Sciences
Volume: 536
ISSN (Print): 0020-0255
Original language: English
ASJC Scopus subject areas: Software, Control and Systems Engineering, Theoretical Computer Science, Computer Science Applications, Information Systems and Management, Artificial Intelligence
Keywords: Fuzzy relation equation, Residuated lattice, T-norm
URLs: 
Source: Scopus
Source ID: 85085840362

Research output: Contribution to journalArticleScientificpeer-review

Using Deep Learning for price prediction by exploiting stationary limit order book features

The recent surge in Deep Learning (DL) research of the past decade has successfully provided solution to many difficult problems. The field of Quantitative analysis has been slowly adapting the new methods to its problems, but due to problems such as the non-stationary nature of financial data, significant challenges must be overcome before DL is fully utilized. In this work a new method to construct stationary features is proposed such that allows DL models to be applied effectively. These features are thoroughly tested on the task of predicting mid price movements of the Limit Order Book. Several DL models are evaluated such as recurrent Long Short Term Memory (LSTM) networks and Convolutional Neural Networks (CNN). Finally a novel model that combines the ability of the CNN to extract useful features and the ability of LSTMs’ to analyse time series, is proposed and evaluated. The combined model is able to outperform the individual LSTM and CNN models in the prediction horizons that are tested.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences, Aristotle University of Thessaloniki, University of Milan Bicocca, Department of Informatics, Aarhus Universitet
Contributors: Tsantekidis, A., Passalis, N., Tefas, A., Kanniainen, J., Gabbouj, M., Iosifidis, A.
Publication date: 1 Aug 2020
Peer-reviewed: Yes

Publication information

Journal: Applied Soft Computing Journal
Volume: 93
Article number: 106401
ISSN (Print): 1568-4946
Original language: English
ASJC Scopus subject areas: Software
Keywords: Deep Learning, Limit order book, Price forecasting, Stationary features

Bibliographical note

EXT="Tefas, Anastasios"
EXT="Iosifidis, Alexandros"

Source: Scopus
Source ID: 85084845392

Research output: Contribution to journalArticleScientificpeer-review

Executing dataflow actors as kahn processes

Programming models which specify an application as a network of independent computational elements have emerged as a promising paradigm for programming streaming applications. The antagonism between expressivity and analysability has led to a number of different such programming models, which provide different degrees of freedom to the programmer. One example are Kahn process networks (KPNs), which, due to certain restrictions in communication, can guarantee determinacy (their results are independent of timing by construction). On the other hand, certain dataflow models, such as the CAL Actor Language, allow non-determinacy and thus higher expressivity, however at the price of static analysability and thus a potentially less efficient implementation. In many cases, however, non-determinacy is not required (or even not desired), and relying on KPN for the implementation seems advantageous. In this paper, we propose an algorithm for classifying dataflow actors (i.e. computational elements) as KPN compatible or potentially not. For KPN compatible dataflow actors, we propose an automatic KPN translation method based on this algorithm. In experiments, we show that more than 75% of all mature actors of a standard multimedia benchmark suite can be classified as KPN compatible and that their execution time can be reduced by up to 1.97x using our proposed translation technique. Finally, in a manual classification effort, we validate these results and list different classes of KPN incompatibility.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing Research Community (SPRC), HCI e 486.1, Dept. of Computer Science and Engineering, Univ of Oulu
Contributors: Tretter, A., Boutellier, J., Guthrie, J., Schor, L., Thiele, L.
Number of pages: 10
Pages: 105-114
Publication date: 4 Nov 2015

Host publication information

Title of host publication: 2015 Proceedings of the International Conference on Embedded Software, EMSOFT 2015
Publisher: Institute of Electrical and Electronics Engineers Inc.
Article number: 7318265
ISBN (Electronic): 9781467380799
ASJC Scopus subject areas: Software
Keywords: classification, Dataflow programming, Kahn process networks
Source: Scopus
Source ID: 84962325193

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Toward efficient many-core scheduling of partial expansion graphs

Transformation of synchronous data flow graphs (SDF) into equivalent homogeneous SDF representations has been extensively applied as a pre-processing stage when mapping signal processing algorithms onto parallel platforms. While this transformation helps fully expose task and data parallelism, it also presents several limitations such as an exponential increase in the number of actors and excessive communication overhead. Partial expansion graphs were introduced to address these limitations for multi-core platforms. However, existing solutions are not well-suited to achieve efficient scheduling on many-core architectures. In this article, we develop a new approach that employs cyclo-static data flow techniques to provide a simple but efficient method of coordinating the data production and consumption in the expanded graphs. We demonstrate the advantage of our approach through experiments on real application models.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Research area: Computer engineering, Parc Scientifique de la Haute Borne, University of Maryland
Contributors: Tran, H. N., Bhattacharyya, S. S., Talpin, J. P., Gautier, T.
Number of pages: 4
Pages: 100-103
Publication date: 28 May 2018

Host publication information

Title of host publication: Proceedings of the 21st International Workshop on Software and Compilers for Embedded Systems, SCOPES 2018
Publisher: Association for Computing Machinery, Inc
ISBN (Print): 9781450357807
ASJC Scopus subject areas: Hardware and Architecture, Software
Source: Scopus
Source ID: 85054140820

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

PyGOP: A Python library for Generalized Operational Perceptron algorithms

PyGOP provides a reference implementation of existing algorithms using Generalized Operational Perceptron (GOP), a recently proposed artificial neuron model. The implementation adopts a user-friendly interface while allowing a high level of customization including user-defined operators, custom loss function, custom metric functions that requires full batch evaluation such as Precision, Recall or F1. Besides, PyGOP supports different computation environments (CPU/GPU) on both single machine and cluster using SLURM job scheduler. In addition, since training GOP-based algorithms might take days, PyGOP automatically saves checkpoints during computation and allows resuming to the last checkpoint in case the script got interfered in the middle during the progression.

General information

Publication status: Accepted/In press
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences, Qatar University, Aarhus Universitet
Contributors: Tran, D. T., Kiranyaz, S., Gabbouj, M., Iosifidis, A.
Publication date: 2019
Peer-reviewed: Yes

Publication information

Journal: Knowledge-Based Systems
ISSN (Print): 0950-7051
Ratings: 
  • Scopus rating (2019): CiteScore 11.7 SJR 1.754 SNIP 2.902
Original language: English
ASJC Scopus subject areas: Software, Management Information Systems, Information Systems and Management, Artificial Intelligence
Keywords: Generalized Operational Perceptron (GOP), Heterogeneous Multilayer Generalized Operational Perceptron (HeMLGOP), Progressive Operational Perceptron (POP), Progressive Operational Perceptron with Memory (POPmem)

Bibliographical note

EXT="Kiranyaz, Serkan"
EXT="Iosifidis, Alexandros"

Source: Scopus
Source ID: 85066982487

Research output: Contribution to journalArticleScientificpeer-review

Lean manufacturing methods in simulation literature: Review and association analysis

The lean manufacturing philosophy includes several methods that aim to remove waste from production. This paper studies lean manufacturing methods and how simulation is used to consider them. In order to do this, it reviews papers that study simulation together with lean methods. The papers that are reviewed are categorized according to the lean methods used and result types obtained. Analysis is performed in order to gain knowledge about the volumes of occurrence of different methods and result types. Typical methods in the papers are different types of value stream mapping and work-in-process models. An exploratory analysis is performed to reveal the relationships between the methods and result types. This is done using association analysis. It reveals the methods that are commonly studied together in the literature. The paper also lists research areas that are not considered in the literature. These areas are often related to the analysis of variation.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Mechanical Engineering and Industrial Systems, Research area: Manufacturing and Automation, Aalto University, Department of Engineering Design and Production
Contributors: Tokola, H., Niemi, E., Väistö, V.
Number of pages: 10
Pages: 2239-2248
Publication date: 16 Feb 2016

Host publication information

Title of host publication: 2015 Winter Simulation Conference (WSC)
ISBN (Print): 978-1-4673-9743-8
ASJC Scopus subject areas: Software, Modelling and Simulation, Computer Science Applications

Bibliographical note

EXT="Niemi, Esko"

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Of discs, boxes and cartridges: The material life of digital games

So far the field of game studies has mostly bypassed the everyday meanings attached to the material manifestations of digital games. Based on qualitative survey data, this article examines what kind of personal and collective values are attached to the physical copies of games, including the storage medium and packaging. The results show how materiality resonates with the reliability and unambiguity of ownership. Furthermore, games as physical objects can have a key role in the project of creating a home, receiving their meaning as part of a wider technological and popular cultural meaning structure. Finally, collecting associates games with more general issues of identity, sociability and history. Through storing and organising games and having them on display, gamers position themselves as part of game culture, gather subcultural capital and ensure the possibility for nostalgia.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Mathematical modelling with wide societal impact (MathImpact)
Contributors: Toivonen, S., Sotamaa, O.
Publication date: 2011

Host publication information

Title of host publication: Proceedings of DiGRA 2011 Conference: Think Design Play
ASJC Scopus subject areas: Computer Graphics and Computer-Aided Design, Human-Computer Interaction, Software
Keywords: Collecting, Digital distribution, Domestication, Game culture, Material culture, Nostalgia, Physical copies
Source: Scopus
Source ID: 84873337886

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Comparison of Feature Selection Techniques in Machine Learning for Anatomical Brain MRI in Dementia

We present a comparative split-half resampling analysis of various data driven feature selection and classification methods for the whole brain voxel-based classification analysis of anatomical magnetic resonance images. We compared support vector machines (SVMs), with or without filter based feature selection, several embedded feature selection methods and stability selection. While comparisons of the accuracy of various classification methods have been reported previously, the variability of the out-of-training sample classification accuracy and the set of selected features due to independent training and test sets have not been previously addressed in a brain imaging context. We studied two classification problems: 1) Alzheimer’s disease (AD) vs. normal control (NC) and 2) mild cognitive impairment (MCI) vs. NC classification. In AD vs. NC classification, the variability in the test accuracy due to the subject sample did not vary between different methods and exceeded the variability due to different classifiers. In MCI vs. NC classification, particularly with a large training set, embedded feature selection methods outperformed SVM-based ones with the difference in the test accuracy exceeding the test accuracy variability due to the subject sample. The filter and embedded methods produced divergent feature patterns for MCI vs. NC classification that suggests the utility of the embedded feature selection for this problem when linked with the good generalization performance. The stability of the feature sets was strongly correlated with the number of features selected, weakly correlated with the stability of classification accuracy, and uncorrelated with the average classification accuracy.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Signal Processing, Research group: Vision, Department of Bioengineering and Aerospace Engineering, Universidad Carlos III de Madrid, Instituto de Investigación Sanitaria Gregorio Marañon
Contributors: Tohka, J., Moradi, E., Huttunen, H., Alzheimer’s Disease Neuroimaging Initiative, Alzheimer’s Disease Neuroimaging Initiative 2
Number of pages: 18
Pages: 279-296
Publication date: 2016
Peer-reviewed: Yes

Publication information

Journal: Neuroinformatics
Volume: 14
Issue number: 3
ISSN (Print): 1539-2791
Ratings: 
  • Scopus rating (2016): CiteScore 5.4 SJR 1.358 SNIP 1.047
Original language: English
ASJC Scopus subject areas: Neuroscience(all), Information Systems, Software
Keywords: Alzheimer’s Disease, Classification, Feature selection, Machine Learning, Magnetic Resonance Imaging, Multivariate pattern analysis

Bibliographical note

EXT="Tohka, Jussi"

Source: Scopus
Source ID: 84955306208

Research output: Contribution to journalArticleScientificpeer-review

Multilinear class-specific discriminant analysis

There has been a great effort to transfer linear discriminant techniques that operate on vector data to high-order data, generally referred to as Multilinear Discriminant Analysis (MDA) techniques. Many existing works focus on maximizing the inter-class variances to intra-class variances defined on tensor data representations. However, there has not been any attempt to employ class-specific discrimination criteria for the tensor data. In this paper, we propose a multilinear subspace learning technique suitable for applications requiring class-specific tensor models. The method maximizes the discrimination of each individual class in the feature space while retains the spatial structure of the input. We evaluate the efficiency of the proposed method on two problems, i.e. facial image analysis and stock price prediction based on limit order book data.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Signal Processing, Aarhus Universitet, Laboratory of Signal Processing
Contributors: Thanh Tran, D., Gabbouj, M., Iosifidis, A.
Number of pages: 6
Pages: 131-136
Publication date: 1 Dec 2017
Peer-reviewed: Yes

Publication information

Journal: Pattern Recognition Letters
Volume: 100
ISSN (Print): 0167-8655
Ratings: 
  • Scopus rating (2017): CiteScore 5.5 SJR 0.662 SNIP 1.605
Original language: English
ASJC Scopus subject areas: Software, Signal Processing, Computer Vision and Pattern Recognition, Artificial Intelligence
Keywords: Class-specific discriminant learning, Face verification, Multilinear discriminant analysis, Stock price prediction

Bibliographical note

INT=sgn,"Thanh Tran, Dat"

Source: Scopus
Source ID: 85032300703

Research output: Contribution to journalArticleScientificpeer-review

Learning movement synchronization in multi-component robotic systems

Imitation learning of tasks in multi-component robotic systems requires capturing concurrency and synchronization requirements in addition to task structure. Learning time-critical tasks depends furthermore on the ability to model temporal elements in demonstrations. This paper proposes a modeling framework based on Petri nets capable of modeling these aspects in a programming by demonstration context. In the proposed approach, models of tasks are constructed from segmented demonstrations as task Petri nets, which can be executed as discrete controllers for reproduction. We present algorithms that automatically construct models from demonstrations, showing how elements of time-critical tasks can be mapped into task Petri net elements. The approach is validated by an experiment in which a robot plays a musical passage on a keyboard.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Intelligent Hydraulics and Automation, University of Skövde, Aalto University
Contributors: Thabet, M., Montebelli, A., Kyrki, V.
Number of pages: 8
Pages: 249-256
Publication date: 8 Jun 2016

Host publication information

Title of host publication: 2016 IEEE International Conference on Robotics and Automation (ICRA)
Publisher: IEEE
ISBN (Print): 9781467380263
ASJC Scopus subject areas: Software, Artificial Intelligence, Control and Systems Engineering, Electrical and Electronic Engineering
Source: Scopus
Source ID: 84977483663

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Comparing the Built-In Application Architecture Models in the Web Browser

Depending on one's viewpoint, a generic standards-compatible web browser supports three, four or five built-in application rendering and programming models. In this paper, we provide an overview of the built-in client-side web application architectures. While the dominance of the base HTML/CSS/JS technologies cannot be ignored, we foresee Web Components and WebGL gaining popularity as the world moves towards more complex and even richer web applications, including systems supporting virtual and augmented reality.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Nokia, University of Helsinki, USI Lugano
Contributors: Taivalsaari, A., Mikkonen, T., Pautasso, C., Systä, K.
Number of pages: 4
Pages: 51-54
Publication date: 16 May 2017

Host publication information

Title of host publication: 2017 IEEE International Conference on Software Architecture (ICSA)
Publisher: IEEE
Article number: 7930198
ISBN (Electronic): 9781509057290
ASJC Scopus subject areas: Software, Computer Networks and Communications, Hardware and Architecture
Keywords: web application architectures, Web development

Bibliographical note

EXT="Taivalsaari, Antero"
EXT="Mikkonen, Tommi"
jufoid=69204

Source: Scopus
Source ID: 85021433872

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Microservices in agile software development: A workshop-based study into issues, advantages, and disadvantages

In the last years, cloud-native architectures have emerged as a target platform for the deployment of microservice architectures. The migration of existing monoliths into cloud-native applications is still in the early phase, and only few companies already started their migrations. Therefore, success and failure stories about different approaches are not available in the literature. This context connects also to the recently discussed DevOps context where development and continuous deployment are closely linked.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Free University of Bolzano-Bozen, Former organisation of the author
Contributors: Taibi, D., Lenarduzzi, V., Pahl, C., Janes, A.
Publication date: 22 May 2017

Host publication information

Title of host publication: Proceedings of the XP2017 Scientific Workshops, XP 2017
Volume: Part F129907
Publisher: Association for Computing Machinery
Article number: a23
ISBN (Electronic): 9781450352642
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Cloud software, Microservices, SOA, Software architecture
Source: Scopus
Source ID: 85029863670

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Operationalizing the experience factory for effort estimation in agile processes

[Background] The effort required to systematically collect historical data is not always allocable in agile processes and historical data management is usually delegated to the developers' experience, who need to remember previous project details. However, even if well trained, developers cannot precisely remember a huge number of details, resulting in wrong decisions being made during the development process. [Aims] The goal of this paper is to operationalize the Experience Factory in an agile way, i.e., defining a strategy for collecting historical project data using an agile approach. [Method] We provide a mechanism for understanding whether a measure must be collected or not, based on the Return on Invested Time (ROIT). In order to validate this approach, we instantiated the factory with an exploratory case study, comparing four projects that did not use our approach with one project that used it after 12 weeks out of 37 and two projects that used it from the beginning. [Results] The proposed approach helps developers to constantly improve their estimation accuracy with a very positive ROIT of the collected measure. [Conclusions] From this first experience, we can conclude that the Experience Factory can be applied effectively to agile processes, supporting developers in improving their performance and reducing potential decision mistakes.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Fraunhofer IESE, University of Cagliari, Former organisation of the author
Contributors: Taibi, D., Lenarduzzi, V., Diebold, P., Lunesu, I.
Number of pages: 10
Pages: 31-40
Publication date: 15 Jun 2017

Host publication information

Title of host publication: Proceedings of the 21st International Conference on Evaluation and Assessment in Software Engineering, EASE 2017
Volume: Part F128635
Publisher: Association for Computing Machinery
ISBN (Electronic): 9781450348041
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Agile software development, Experience factory, Knowledge management
Source: Scopus
Source ID: 85025449243

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Comparing communication effort within the scrum, scrum with Kanban, XP, and Banana development processes

[Context]: Communication plays an important role in any development process. However, communication overhead has been rarely compared among development processes. [Objective]: The goal of this work is to compare the communication overhead and the different channels applied in three agile processes (XP, Scrum, Scrum with Kanban) and in an unstructured process. [Method]: We designed an empirical study asking four teams to develop the same application with the four development processes, and we compare the communication overhead among them. [Results]: As expected, face-to-face communication is most frequently employed in the teams. Scrum with Kanban turned out to be the process that requires the least communication. Unexpectedly, despite requiring much more time to develop the same application, the unstructured process required comparable communication overhead (25% of the total development time) as the agile processes.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: University of Oulu, Former organisation of the author
Contributors: Taibi, D., Lenarduzzi, V., Ahmad, M. O., Liukkunen, K.
Number of pages: 6
Pages: 258-263
Publication date: 15 Jun 2017

Host publication information

Title of host publication: Proceedings of the 21st International Conference on Evaluation and Assessment in Software Engineering, EASE 2017
Volume: Part F128635
Publisher: Association for Computing Machinery
ISBN (Electronic): 9781450348041
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Agile processes, Case study, Communication, Empirical software engineering
Source: Scopus
Source ID: 85025468824

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

How developers perceive smells in source code: A replicated study

Context. In recent years, smells, also referred to as bad smells, have gained popularity among developers. However, it is still not clear how harmful they are perceived from the developers’ point of view. Many developers talk about them, but only few know what they really are, and even fewer really take care of them in their source code. Objective. The goal of this work is to understand the perceived criticality of code smells both in theory, when reading their description, and in practice. Method. We executed an empirical study as a differentiated external replication of two previous studies. The studies were conducted as surveys involving only highly experienced developers (63 in the first study and 41 in the second one). First the perceived criticality was analyzed by proposing the description of the smells, then different pieces of code infected by the smells were proposed, and finally their ability to identify the smells in the analyzed code was tested. Results. According to our knowledge, this is the largest study so far investigating the perception of code smells with professional software developers. The results show that developers are very concerned about code smells in theory, nearly always considering them as harmful or very harmful (17 out of 23 smells). However, when they were asked to analyze an infected piece of code, only few infected classes were considered harmful and even fewer were considered harmful because of the smell. Conclusions. The results confirm our initial hypotheses that code smells are perceived as more critical in theory but not as critical in practice.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Free University of Bolzano-Bozen, Free University of Bozen-Bolzano
Contributors: Taibi, D., Janes, A., Lenarduzzi, V.
Number of pages: 13
Pages: 223-235
Publication date: 1 Dec 2017
Peer-reviewed: Yes

Publication information

Journal: Information and Software Technology
Volume: 92
ISSN (Print): 0950-5849
Ratings: 
  • Scopus rating (2017): CiteScore 7.2 SJR 0.581 SNIP 2.913
Original language: English
ASJC Scopus subject areas: Software, Information Systems, Computer Science Applications
Keywords: Antipatterns, Bad smells, Code smells, Refactoring, Software maintenance
Source: Scopus
Source ID: 85028762206

Research output: Contribution to journalArticleScientificpeer-review

On the Definition of Microservice Bad Smells

Code smells and architectural smells (also called bad smells) are symptoms of poor design that can hinder code understandability and decrease maintainability. Several bad smells have been defined in the literature for both generic architectures and specific architectures. However, cloud-native applications based on microservices can be affected by other types of issues. In order to identify a set of microservice-specific bad smells, researchers collected evidence of bad practices by interviewing 72 developers with experience in developing systems based on microservices. Then, they classified the bad practices into a catalog of 11 microservice-specific bad smells frequently considered harmful by practitioners. The results can be used by practitioners and researchers as a guideline to avoid experiencing the same difficult situations in the systems they develop.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Pervasive Computing
Contributors: Taibi, D., Lenarduzzi, V.
Number of pages: 7
Pages: 56-62
Publication date: 1 May 2018
Peer-reviewed: Yes

Publication information

Journal: IEEE Software
Volume: 35
Issue number: 3
ISSN (Print): 0740-7459
Ratings: 
  • Scopus rating (2018): CiteScore 5.3 SJR 0.549 SNIP 2.444
Original language: English
ASJC Scopus subject areas: Software
Keywords: anti-pattern, antipattern, architectural smell, bad smell, cloud computing, code smell, microservice, software development, software engineering
Source: Scopus
Source ID: 85046708734

Research output: Contribution to journalArticleScientificpeer-review

Architectural patterns for microservices: A systematic mapping study

Microservices is an architectural style increasing in popularity. However, there is still a lack of understanding how to adopt a microservice-based architectural style. We aim at characterizing different microservice architectural style patterns and the principles that guide their definition. We conducted a systematic mapping study in order to identify reported usage of microservices and based on these use cases extract common patterns and principles. We present two key contributions. Firstly, we identified several agreed microservice architecture patterns that seem widely adopted and reported in the case studies identified. Secondly, we presented these as a catalogue in a common template format including a summary of the advantages, disadvantages, and lessons learned for each pattern from the case studies. We can conclude that different architecture patterns emerge for different migration, orchestration, storage and deployment settings for a set of agreed principles.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Free University of Bolzano-Bozen
Contributors: Taibi, D., Lenarduzzi, V., Pahl, C.
Number of pages: 12
Pages: 221-232
Publication date: 2018

Host publication information

Title of host publication: CLOSER 2018 - Proceedings of the 8th International Conference on Cloud Computing and Services Science
Publisher: SCITEPRESS
ISBN (Electronic): 9789897582950
ASJC Scopus subject areas: Computer Science (miscellaneous), Software, Computer Science Applications
Keywords: Architectural style, Architecture pattern, Cloud migration, Cloud native, DevOps, Microservices
Source: Scopus
Source ID: 85046716130

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Patterns for serverless functions (Function-as-a-Service): A multivocal literature review

[Context] Serverless is a recent technology that enables companies to reduce the overhead for provisioning, scaling and in general managing the infrastructure. Companies are increasingly adopting Serverless, by migrating existing applications to this new paradigm. Different practitioners proposed patterns for composing and managing serverless functions. However, some of these patterns offer different solutions to solve the same problem, which makes it hard to select the most suitable solution for each problem. [Goal] In this work, we aim at supporting practitioners in understanding the different patterns, by classifying them and reporting possible benefits and issues. [Method]We adopted a multivocal literature review process, surveying peer-reviewed and grey literature and classifying patterns (common solutions to solve common problems), together with benefits and issues. [Results] Among 24 selected works, we identified 32 patterns that we classified as orchestration, aggregation, event-management, availability, communication, and authorization. [Conclusion] Practitioners proposed a list of fairly consistent patterns, even if a small number of patterns proposed different solutions to similar problems. Some patterns emerged to circumvent some serverless limitations, while others for some classical technical problems (e.g. publisher/subscriber).

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Free University of Bolzano-Bozen
Contributors: Taibi, D., El Ioini, N., Pahl, C., Niederkofler, J. R. S.
Number of pages: 12
Pages: 181-192
Publication date: 2020

Host publication information

Title of host publication: CLOSER 2020 - Proceedings of the 10th International Conference on Cloud Computing and Services Science
Volume: 1
Publisher: SCITEPRESS
Editors: Ferguson, D., Helfert, M., Pahl, C.
ISBN (Electronic): 9789897584244
ASJC Scopus subject areas: Computer Science (miscellaneous), Computer Science Applications, Software
Keywords: Cloud, Function as a Service, Serverless, Serverless Functions
Source: Scopus
Source ID: 85088373702

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Prediction models and techniques for Open Source Software projects: A systematic literature review

Open Source Software (OSS) is currently a widely adopted approach to developing and distributing software. For effective adoption of OSS, fundamental knowledge of project development is needed. This often calls for reliable prediction models to simulate project evolution and to envision project future. These models provide help in supporting preventive maintenance and building quality software. This paper reports on a systematic literature survey aimed at the identification and structuring of research that offer prediction models and techniques in analyzing OSS projects. In this review, we systematically selected and reviewed 52 peer reviewed articles that were published between January, 2000 and March, 2013. The study outcome provides insight in what constitutes the main contributions of the field, identifies gaps and opportunities, and distills several important future research directions.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Pervasive Computing, Chalmers and University of Gothenburg
Contributors: Syeed, M. M. M., Hammouda, I., Systä, T.
Number of pages: 39
Pages: 1-39
Publication date: 1 Apr 2014
Peer-reviewed: Yes

Publication information

Journal: International Journal of Open Source Software and Processes
Volume: 5
Issue number: 2
ISSN (Print): 1942-3926
Ratings: 
  • Scopus rating (2014): CiteScore 0.8 SJR 0.28 SNIP 0.291
Original language: English
ASJC Scopus subject areas: Software
Keywords: Fault prediction, Open Source Software, OSS community, Prediction, Systematic literature review

Bibliographical note

EXT="Hammouda, Imed"

Source: Scopus
Source ID: 84924346193

Research output: Contribution to journalArticleScientificpeer-review

Preface: Special Issue on ‘New Hydraulic Components for Tough Robots’

General information

Publication status: Published
MoE publication type: B1 Article in a scientific magazine
Organisations: Automation and Hydraulic Engineering, Research group: Innovative Hydraulic Automation, Tokyo Institute of Technology, Ritsumeikan University, Italian Institute of Technology, Okayama University
Contributors: Suzumori, K., Hyon, S. H., Semini, C., Mattila, J., Kanda, T.
Number of pages: 1
Publication date: 3 May 2018
Peer-reviewed: No

Publication information

Journal: Advanced Robotics
Volume: 32
Issue number: 9
ISSN (Print): 0169-1864
Ratings: 
  • Scopus rating (2018): CiteScore 2.7 SJR 0.346 SNIP 0.886
Original language: English
ASJC Scopus subject areas: Control and Systems Engineering, Software, Human-Computer Interaction, Hardware and Architecture, Computer Science Applications
Source: Scopus
Source ID: 85047515551

Research output: Contribution to journalEditorialScientific

Designing an Unobtrusive Analytics Framework for Monitoring Java Applications

In software development, attention has recently been placed on understanding users and their interactions with systems. User studies, practices such as A/B testing, and frameworks such as Google Analytics that gather data on production use have become common approaches in particular in the context of the Web, where it is easy to perform frequent updates as new needs emerge. However, when considering installable desktop applications, the situation gets more complex. While analytics facilities are still needed, they should address business logic, not generic traffic as is the case with many web sites. Moreover, analytics should be unobtrusive, and not have a high impact on the evolution of the actual application; thus, analytics should be treated as an add-on, as the target system may already exist. Finally, the instrumentation of features that are observed should be easy and flexible, but the provided mechanisms should be expressive enough for many use cases. In this paper, we examine different alternatives for implementing such monitoring mechanisms, and report results from an experiment with Vaadin, a web framework based on Java and Google Web Toolkit, GWT.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Pervasive Computing, Research area: Software engineering
Contributors: Suonsyrjä, S., Mikkonen, T.
Number of pages: 16
Pages: 160-175
Publication date: 2015

Host publication information

Title of host publication: Software Measurement : 25th International Workshop on Software Measurement and 10th International Conference on Software Process and Product Measurement, IWSM-Mensura 2015, Kraków, Poland, October 5–7, 2015, Proceedings
Volume: 230
Publisher: Springer International Publishing
Editors: Kobyliński , A., Czarnacka-Chrobot, B., Świerczek, J.
ISBN (Print): 978-3-319-24284-2
ISBN (Electronic): 978-3-319-24285-9

Publication series

Name: Lecture Notes in Business Information Processing
Publisher: Springer
ASJC Scopus subject areas: Electrical and Electronic Engineering, Software
Keywords: software engineering, software development, case study, software usage data, software analytics

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Collecting usage data for software development: Selection framework for technological approaches

Software development methods are shifting towards faster deployments and closer to the end users. Their ever tighter engagement of end-users also requires new technologies for gathering feedback from those users. At the same time, widespread Internet connectivity of different application environments is enabling the collection of this post-deployment data also from sources other than traditional web and mobile software. However, the sheer number of different alternatives of collecting technologies makes the selection a complicated process in itself. In this paper, we describe the process of data-driven software development and study the challenges organizations face when they want to start guiding their development towards it. From these challenges, we extract evaluation criteria for technological approaches to usage data collecting. We list such approaches and evaluate them using the extracted criteria. Using a design science approach, we refine the evaluation criteria to a selection framework that can help practitioners in finding a suitable technological approach for automated collecting of usage data.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Pervasive Computing, Research area: Software engineering
Contributors: Suonsyrjä, S., Systä, K., Mikkonen, T., Terho, H.
Number of pages: 6
Pages: 114-119
Publication date: 2016

Host publication information

Title of host publication: Proceedings - SEKE 2016: 28th International Conference on Software Engineering and Knowledge Engineering
Publisher: Knowledge Systems Institute Graduate School
ISBN (Electronic): 978-1-891706-39-4
ASJC Scopus subject areas: Software
Electronic versions: 
Source: Scopus
Source ID: 84988423396

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Post-deployment data: A recipe for satisfying knowledge needs in software development?

In the field of improving software processes, one of the clear trends has been the ever tighter engagement of end users in the software development process. This is demonstrated by the shift from Agile processes to Continuous Deployment, which requires more rapid ways to validate the developed software and its value than is possible with traditional communication mechanisms and methods, such as face to face conversations with customers. While post-deployment data has been used for years as an extra data source - companies like Microsoft and Intuit have moved a few steps further from that already - we believe that there are numerous uncovered ways of taking advantage of post-deployment data in software development. In this paper, we study how automatically collected post-deployment data could be used for responding to knowledge needs of software development teams. The paper builds on data collected from a number of companies operating in Finland using a questionnaire study. The focus of questionnaire study was to approach post-deployment data - especially usage data - as means of getting information to support understanding of customer and end users.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Research area: Software engineering
Contributors: Suonsyrjä, S., Hokkanen, L., Terho, H., Systä, K., Mikkonen, T.
Number of pages: 9
Pages: 139-147
Publication date: 6 Jan 2017

Host publication information

Title of host publication: 2016 Joint Conference of the International Workshop on Software Measurement and the International Conference on Software Process and Product Measurement (IWSM-MENSURA)
Publisher: IEEE
ISBN (Electronic): 9781509041473
ASJC Scopus subject areas: Software, Information Systems and Management
Keywords: Agile software development, Post-deployment data, Software development, Software usage data
Source: Scopus
Source ID: 85011977790

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Detection of bubbles as concentric circular arrangements

The paper proposes a method for the detection of bubble-like transparent objects in a liquid. The detection problem is non-trivial since bubble appearance varies considerably due to different lighting conditions causing contrast reversal and multiple interreflections. We formulate the problem as the detection of concentric circular arrangements (CCA). The CCAs are recovered in a hypothesize-optimize-verify framework. The hypothesis generation is based on sampling from the partially linked components of the non-maximum suppressed responses of oriented ridge filters, and is followed by the CCA parameter estimation. Parameter optimization is carried out by minimizing a novel cost-function. The performance was tested on gas dispersion images of pulp suspension and oil dispersion images. The mean error of gas/oil volume estimation was used as a performance criterion due to the fact that the main goal of the applications driving the research was the bubble volume estimation. The method achieved 28 and 13 % of gas and oil volume estimation errors correspondingly outperforming the OpenCV Circular Hough Transform in both cases and the WaldBoost detector in gas volume estimation.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Signal Processing, Research group: Vision, Research Community on Data-to-Decision (D2D), Machine Vision and Pattern Recognition Laboratory, Lappeenranta University of Technology, Computer Vision Group, Czech Technical University in Prague, Monash University Malaysia
Contributors: Strokina, N., Matas, J., Eerola, T., Lensu, L., Kälviäinen, H.
Number of pages: 10
Pages: 387-396
Publication date: Apr 2016
Peer-reviewed: Yes
Early online date: 10 Feb 2016

Publication information

Journal: Machine Vision and Applications
Volume: 27
Issue number: 3
ISSN (Print): 0932-8092
Ratings: 
  • Scopus rating (2016): CiteScore 4.7 SJR 0.741 SNIP 1.433
Original language: English
ASJC Scopus subject areas: Hardware and Architecture, Computer Vision and Pattern Recognition, Software, Computer Science Applications
Keywords: Bubble detection, Circular arrangements, Image processing, Machine vision, Object segmentation
Source: Scopus
Source ID: 84957656160

Research output: Contribution to journalArticleScientificpeer-review

The making of Nordic larp: Documenting a tradition of ephemeral co-creative play

Research and documentation of live action role-playing games, or larps, must tackle problems of ephemerality, subjectivity, first person audience and co-creation, as well as the underlying question of what larps are. In this paper these challenges are outlined and solutions to handling them are proposed. This is done through the prism of producing a picture-heavy art book on Nordic larp. The paper also discussed the problems of writing about game cultures as an insider and makes a case for addressing normative choices in game descriptions head on.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Mathematical modelling with wide societal impact (MathImpact)
Contributors: Stenros, J., Montola, M.
Publication date: 2011

Host publication information

Title of host publication: Proceedings of DiGRA 2011 Conference: Think Design Play
ASJC Scopus subject areas: Computer Graphics and Computer-Aided Design, Human-Computer Interaction, Software
Keywords: Documentation, Game culture, Games, Larp, Nordic, Play, Role-playing games
Source: Scopus
Source ID: 84873389573

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Narrative friction in Alternate Reality Games: Design insights from conspiracy for good

Alternate Reality Games (ARG) tend to have story-driven game structures. Hence, it is useful to investigate how player activities interact with the often pre-scripted storyline in this genre. In this article, we report on a study of a particular ARG production, Conspiracy For Good (CFG), which was at the same time emphasising the role of strong storytelling, and active on-site participation by players. We uncover multiple levels of friction between the story content and the mode of play of live participants, but also between live and online participation. Based on the observations from the production, we present design recommendations for future productions with similar goals.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Mathematical modelling with wide societal impact (MathImpact), Nokia, Stockholm University
Contributors: Stenros, J., Holopainen, J., Waern, A., Montola, M., Ollila, E.
Publication date: 2011

Host publication information

Title of host publication: Proceedings of DiGRA 2011 Conference: Think Design Play
ASJC Scopus subject areas: Computer Graphics and Computer-Aided Design, Human-Computer Interaction, Software
Keywords: ARG, Design, Gameplay, Games, Larp, Narrative, Pervasive, Transmedia
Source: Scopus
Source ID: 84873344376

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Enhanced gaze interaction using simple head gestures

We propose a combination of gaze pointing and head gestures for enhanced hands-free interaction. Instead of the traditional dwell-time selection method, we experimented with five simple head gestures: nodding, turning left/right, and tilting left/right. The gestures were detected from the eye-tracking data by a range-based algorithm, which was found accurate enough in recognizing nodding and leftdirected gestures. The gaze estimation accuracy did not noticeably suffer from the quick head motions. Participants pointed to nodding as the best gesture for occasional selections tasks and rated the other gestures as promising methods for navigation (turning) and functional mode switching (tilting). In general, dwell time works well for repeated tasks such as eye typing. However, considering multimodal games or transient interactions in pervasive and mobile environments, we believe a combination of gaze and head interaction could potentially provide a natural and more accurate interaction method.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA)
Contributors: Špakov, O., Majaranta, P.
Number of pages: 6
Pages: 705-710
Publication date: 2012

Host publication information

Title of host publication: UbiComp'12 - Proceedings of the 2012 ACM Conference on Ubiquitous Computing
ISBN (Print): 9781450312240
ASJC Scopus subject areas: Software
Keywords: Dwell time, Eye tracking, Head gestures, Selection
Source: Scopus
Source ID: 84879496342

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Comparison of gaze-to-objects mapping algorithms

Gaze data processing is an important and necessary step in gaze-based applications. This study focuses on the comparison of several gaze-to-object mapping algorithms using various dwell times for selection and presenting targets of several types and sizes. Seven algorithms found in literature were compared against two newly designed algorithms. The study revealed that a fractional mapping algorithm (known) has produced the highest rate of correct selections and fastest selection times, but also the highest rate of incorrect selections. The dynamic competing algorithm (designed) has shown the next best result, but also high rate of incorrect selections. A small impact on the type of target to the calculated statistics has been observed. A strictly centered gazing has helped to increase the rate of correct selections for all algorithms and types of targets. The directions for further mapping algorithms improvement and future investigation have been explained.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA)
Contributors: Špakov, O.
Publication date: 2011

Host publication information

Title of host publication: Proceedings of the 1st Conference on Novel Gaze-Controlled Applications, NGCA'11
Article number: 6
ISBN (Print): 9781450306805
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Algorithm design, Eye gaze pointing and selection, Gaze controlled applications, Gaze to object mapping
Source: Scopus
Source ID: 79960161638

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Multimodal subspace support vector data description

In this paper, we propose a novel method for projecting data from multiple modalities to a new subspace optimized for one-class classification. The proposed method iteratively transforms the data from the original feature space of each modality to a new common feature space along with finding a joint compact description of data coming from all the modalities. For data in each modality, we define a separate transformation to map the data from the corresponding feature space to the new optimized subspace by exploiting the available information from the class of interest only. We also propose different regularization strategies for the proposed method and provide both linear and non-linear formulations. The proposed Multimodal Subspace Support Vector Data Description outperforms all the competing methods using data from a single modality or fusing data from all modalities in four out of five datasets.

General information

Publication status: E-pub ahead of print
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences, Research group: Multimedia Research Group - MRG, Finnish Environment Institute, Aarhus Universitet
Contributors: Sohrab, F., Raitoharju, J., Iosifidis, A., Gabbouj, M.
Number of pages: 13
Publication date: 2020
Peer-reviewed: Yes

Publication information

Journal: Pattern Recognition
Volume: 110
Article number: 107648
ISSN (Print): 0031-3203
Original language: English
ASJC Scopus subject areas: Software, Signal Processing, Computer Vision and Pattern Recognition, Artificial Intelligence
Keywords: Feature transformation, Multimodal data, One-class classification, Subspace learning, Support vector data description

Bibliographical note

EXT="Iosifidis, Alexandros"

Source: Scopus
Source ID: 85090954677

Research output: Contribution to journalArticleScientificpeer-review

Collaboration change in enterprise software development

Enterprise software development is a complex effort that may last years. Enterprise software is often developed by a systems integrator that makes modifications to a pre-made package or builds tailored software for the specific purpose. The development may include many developer organizations, the user organization, and their different departments and sub-units. Their collaboration evolves through project incidents, phases and even crises. The practices of project management, communication, contracts, and ultimately personal relationships change intentionally or unintentionally. These changes may cause uncertainties and discontinuities for the development. This study observes changes during enterprise software development and their influence on collaboration practices in different situations. During twenty years of development both internal and external crises and changes in the business environment triggered changes in collaboration. The collaboration practices are classified with four modes of collaboration (contract, cooperation, personified, and process) that illustrate emphasis in collaboration in different circumstances.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Information Management and Logistics, Research group: Novi, Aalto University
Contributors: Smolander, K., Rossi, M., Pekkola, S.
Number of pages: 7
Pages: 68-74
Publication date: 14 May 2016

Host publication information

Title of host publication: Proceedings - 9th International Workshop on Cooperative and Human Aspects of Software Engineering, CHASE 2016
Publisher: ACM
ISBN (Print): 9781450341554
ASJC Scopus subject areas: Organizational Behavior and Human Resource Management, Social Psychology, Software
Keywords: Collaboration, Collaboration change, Enterprise software, Project management
Source: Scopus
Source ID: 84974527974

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Interaction strategies for an affective conversational agent

The development of embodied conversational agents (ECA) as companions brings several challenges for both affective and conversational dialogue. These include challenges in generating appropriate affective responses, selecting the overall shape of the dialogue, providing prompt system response times, and handling interruptions. We present an implementation of such a companion showing the development of individual modules that attempt to address these challenges. Further, to resolve resulting conflicts, we present encompassing interaction strategies that attempt to balance the competing requirements along with dialogues from our working prototype to illustrate these interaction strategies in operation. Finally, we provide the results of an evaluation of the companion using an evaluation methodology created for conversational dialogue and including analysis using appropriateness annotation.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Augmented Human Activities (AHA), School of Computing Teesside University Middlesbrough, University of Oxford, Telefonica, School of Management (JKK), School of Computing Edinburgh Napier University Edinburgh, SICS SE-164 29 Kista, ILS Institute SUNY Albany Albany
Contributors: Smith, C., Crook, N., Dobnik, S., Charlton, D., Boye, J., Pulman, S., Santos de la Camara, R., Turunen, M., Benyon, D., Bradley, J., Gambäck, B., Hansen, P., Mival, O., Webb, N., Cavazza, M.
Number of pages: 17
Pages: 395-411
Publication date: Oct 2011
Peer-reviewed: Yes

Publication information

Journal: Presence: Teleoperators and Virtual Environments
Volume: 20
Issue number: 5
ISSN (Print): 1054-7460
Ratings: 
  • Scopus rating (2011): CiteScore 3 SJR 0.354 SNIP 1.141
Original language: English
ASJC Scopus subject areas: Control and Systems Engineering, Software, Human-Computer Interaction, Computer Vision and Pattern Recognition
Source: Scopus
Source ID: 84863122938

Research output: Contribution to journalArticleScientificpeer-review

Investigation of egocentric social structures for diversity-enhancing followee recommendations

The increasing amount of data in social media enables new advanced user modeling approaches. This paper focuses on user profiling for diversity-enhancing recommender systems for finding new followees on Twitter. By combining social network analysis with Latent Dirichlet Allocation based content analysis, we defined three egocentric structural positions on the network extracted from Twitter data: Mentions of Mentions, Community Cluster, Dormant Ties (and the rest as a baseline condition). In addition to describing the data analysis procedure, we report preliminary empirical findings on a user-centered evaluation study of recommendations based on the proposed matching strategy and the presented structural positions. The investigation of the possible overlaps of the groups and the participants' evaluations of perceived relevance of the recommendation imply that the three positions are sufficiently mutually exclusive and thus could serve as new diversity-enhancing mechanisms in various people recommender systems.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Information and Knowledge Management, Computing Sciences, Tampere University
Contributors: Skenderi, E., Olshannikova, E., Olsson, T., Huhtamäki, J., Koivunen, S., Yao, P., Huttunen, H.
Number of pages: 5
Pages: 257-261
Publication date: 6 Jun 2019

Host publication information

Title of host publication: ACM UMAP 2019 Adjunct - Adjunct Publication of the 27th Conference on User Modeling, Adaptation and Personalization
Publisher: ACM
ISBN (Electronic): 9781450367110
ASJC Scopus subject areas: Software
Keywords: Hybrid recommendation system, People recommender system, Social network analysis, Social recommender system, Twitter analytics, User modeling for social matching

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Liking the game: How can spectating motivations influence social media usage at live esports events?

There is no doubt that various social media services shape the ways in which we approach our daily lives. The ubiquitous nature of these services, afforded by mobile devices, means that we can take them with us wherever we go — including when we attend live events. Uncovering why individuals use social media during live events can help improve event organization, marketing, and the experiences of attendees. Our understanding of the motivations for using social media during live events is, however, still lacking in depth, especially in regard to emerging live events such as esports. This study aims to answer the question: what motivates the use of social media during live esports events? Data was gathered via a survey (N=255) at the ‘Assembly 2016’ LAN-event, a major live esports event. We examine the relationships between using various social media services and the motivations for esports spectating, through the Motivation Scale for Sports Consumption. While the results indicate that using social media services while attending Assembly 2016 was quite popular, it seemed that in many cases social media usage was a distraction from esports spectating, a core activity of the event. The results provide implications as to how marketers of live esports events should encourage or control usage of social media by attendees.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Gamification Group, Gamification Group
Contributors: Sjöblom, M., Hassan, L., Macey, J., Törhönen, M., Hamari, J.
Number of pages: 8
Pages: 160-167
Publication date: 18 Jul 2018

Host publication information

Title of host publication: Proceedings of the 9th International Conference on Social Media and Society, SMSociety 2018
Publisher: ACM
ISBN (Print): 9781450363341
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Esports, Live events, Motivation, Social media, Sports consumption
Electronic versions: 

Bibliographical note

EXT="Törhönen, Maria"
DUPL=44481582

Source: Scopus
Source ID: 85051509297

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

The Double Shadowed κ-μ Fading Model

In this paper, we introduce a new fading model which is capable of characterizing both the shadowing of the dominant component and composite shadowing which may exist in wireless channels. More precisely, this new model assumes a κ-μ envelope where the dominant component is fluctuated by a Nakagami-m random variable (RV) which is preceded (or succeeded) by a secondary round of shadowing brought about by an inverse Nakagami-m RV. We conveniently refer to this as the double shadowed κ-μ fading model. In this context, novel closed-form and analytical expressions are developed for a range of channel related statistics, such as the probability density function, cumulative distribution function, and moments. All of the derived expressions have been validated through Monte-Carlo simulations and reduction to a number of well-known special cases. It is worth highlighting that the proposed fading model offers remarkable flexibility as it includes the κ-μ, η-μ, Rician shadowed, double shadowed Rician, κ-μ shadowed, κ-μ/inverse gamma and η-μ/inverse gamma distributions as special cases.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research group: Wireless Communications and Positioning, Electrical Engineering, Queen's University, Belfast, Northern Ireland, Universidade Estadual de Campinas, Center on Cyber-Physical Systems, Khalifa University, Tampere University of Applied Sciences
Contributors: Simmons, N., Nogueira Da Silva, C. R., Cotton, S. L., Sofotasios, P. C., Ki Yoo, S., Yacoub, M. D.
Publication date: 1 Oct 2019

Host publication information

Title of host publication: 2019 International Conference on Wireless and Mobile Computing, Networking and Communications, WiMob 2019
Publisher: IEEE
ISBN (Electronic): 9781728133164

Publication series

Name: International Conference on Wireless and Mobile Computing, Networking and Communications
ISSN (Print): 2161-9646
ISSN (Electronic): 2161-9654
ASJC Scopus subject areas: Computer Networks and Communications, Hardware and Architecture, Software
Source: Scopus
Source ID: 85077583520

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Collaborative cloud-based management of home networks

Future home networks are expected to become extremely sophisticated, yet only the most technically adept persons are equipped with skills to manage them. In this paper, we provide a novel solution as to how complex smart home networks can be collaboratively managed with the assistance of operators and third party experts. Our solution rests in separating the management and control functionalities of the home access points and routers, away from the actual connectivity, traffic forwarding and routing operations within the home network. By so doing, we present a novel REST-based architecture in which the management of the home network can be hosted in an entirely separate, external cloud-based infrastructure, which models the network within the home as a resource graph.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Pervasive Computing, Research area: Information security, Tampere University of Technology
Contributors: Silverajan, B., Luoma, J., Vajaranta, M., Itäpuro, R.
Number of pages: 4
Pages: 786-789
Publication date: 29 Jun 2015

Host publication information

Title of host publication: Proceedings of the 2015 IFIP/IEEE International Symposium on Integrated Network Management, IM 2015
Publisher: IEEE
ISBN (Print): 9783901882760
ASJC Scopus subject areas: Software, Computer Science Applications, Computer Networks and Communications
Keywords: Cloud, Homenet, IoT, Network Management
Source: Scopus
Source ID: 84942601939

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Enabling cybersecurity incident reporting and coordinated handling for maritime sector

The maritime industry is experiencing a new era of digital transformation. At the same time as the number of cyberattacks and cybersecurity incidents are increasing, cybersecurity awareness and incident reporting in this sector remains low. In this paper, we describe a cybersecurity incident reporting system for the maritime industry that aims to address this issue. The work focuses on autonomous and unmanned vessels, but can be equally applied to other areas of the maritime industry. The proposed approach has been evaluated experimentally and the results demonstrate its applicability and feasibility.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Research area: Information security
Contributors: Silverajan, B., Vistiaho, P.
Number of pages: 8
Pages: 88-95
Publication date: 1 Aug 2019

Host publication information

Title of host publication: 2019 14th Asia Joint Conference on Information Security, AsiaJCIS 2019
Publisher: IEEE
ISBN (Electronic): 9781728125565
ASJC Scopus subject areas: Software, Information Systems and Management, Computer Networks and Communications, Safety, Risk, Reliability and Quality
Keywords: Cybersecurity incident exchange, Maritime cybersecurity, Smart ports, Smart ships

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Challenges and recommended practices for software architecting in global software development

Context: Global software development (GSD), although now a norm in the software industry, carries with it enormous challenges mostly regarding communication and coordination. Aforementioned challenges are highlighted when there is a need to transfer knowledge between sites, particularly when software artifacts assigned to different sites depend on each other. The design of the software architecture and associated task dependencies play a major role in reducing some of these challenges. Objective: The current literature does not provide a cohesive picture of how the distributed nature of software development is taken into account during the design phase: what to avoid, and what works in practice. The objective of this paper is to gain an understanding of software architecting in the context of GSD, in order to develop a framework of challenges and solutions that can be applied in both research and practice. Method: We conducted a systematic literature review (SLR) that synthesises (i) challenges which GSD imposes on software architecture design, and (ii) recommended practices to alleviate these challenges. Results: We produced a comprehensive set of guidelines for performing software architecture design in GSD based on 55 selected studies. Our framework comprises nine key challenges with 28 related concerns, and nine recommended practices, with 22 related concerns for software architecture design in GSD. These challenges and practices were mapped to a thematic conceptual model with the following concepts: Organization (Structure and Resources), Ways of Working (Architecture Knowledge Management, Change Management and Quality Management), Design Practices, Modularity and Task Allocation. Conclusion: The synthesis of findings resulted in a thematic conceptual model of the problem area, a mapping of the key challenges to practices, and a concern framework providing concrete questions to aid the design process in a distributed setting. This is a first step in creating more concrete architecture design practices and guidelines.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Pervasive Computing, Research area: Software engineering, University of Limerick
Contributors: Sievi-Korte, O., Beecham, S., Richardson, I.
Number of pages: 20
Pages: 234-253
Publication date: 1 Feb 2019
Peer-reviewed: Yes
Early online date: 2018

Publication information

Journal: Information and Software Technology
Volume: 106
ISSN (Print): 0950-5849
Ratings: 
  • Scopus rating (2019): CiteScore 7.6 SJR 0.781 SNIP 2.555
Original language: English
ASJC Scopus subject areas: Software, Information Systems, Computer Science Applications
Keywords: Design practice, Global software development, Software architecture, Software design, Systematic literature review
URLs: 
Source: Scopus
Source ID: 85055646041

Research output: Contribution to journalArticleScientificpeer-review

Software architecture design in global software development: An empirical study

In Global Software Development (GSD), the additional complexity caused by global distance requires processes to ease collaboration difficulties, reduce communication overhead, and improve control. How development tasks are broken down, shared and prioritized is key to project success. While the related literature provides some support for architects involved in GSD, guidelines are far from complete. This paper presents a GSD Architectural Practice Framework reflecting the views of software architects, all of whom are working in a distributed setting. In-depth interviews with architects from seven different GSD organizations revealed a complex set of challenges and practices. We found that designing software for distributed teams requires careful selection of practices that support understanding and adherence to defined architectural plans across sites. Teams used Scrum which aided communication, and Continuous Integration which helped solve synchronization issues. However, teams deviated from the design, causing conflicts. Furthermore, there needs to be a balance between the self-organizing Scrum team methodology and the need to impose architectural design decisions across distributed sites. The research presented provides an enhanced understanding of architectural practices in GSD companies. Our GSD Architectural Practice Framework gives practitioners a cohesive set of warnings, which for the most part, are matched by recommendations.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences, Research area: Software engineering, University of Limerick
Contributors: Sievi-Korte, O., Richardson, I., Beecham, S.
Publication date: 1 Dec 2019
Peer-reviewed: Yes

Publication information

Journal: Journal of Systems and Software
Volume: 158
Article number: 110400
ISSN (Print): 0164-1212
Ratings: 
  • Scopus rating (2019): CiteScore 7.8 SJR 0.772 SNIP 2.387
Original language: English
ASJC Scopus subject areas: Software, Information Systems, Hardware and Architecture
Keywords: Empirical study, Global software development, GSD, GSE, Scrum, Software architecture
URLs: 
Source: Scopus
Source ID: 85072283236

Research output: Contribution to journalArticleScientificpeer-review

Dynamic text presentation in print interpreting - An eye movement study of reading behaviour

Print interpreting supports people with a hearing disability by giving them access to spoken language. In print interpreting, the interpreter types the spoken text in real time for the hard-of-hearing client to read. This results in dynamic text presentation. An eye movement study was conducted to compare two types of dynamic text presentation formats in print interpreting: letter-by-letter and word-by-word. Gaze path analysis with 20 hearing participants showed different types of reading behaviour during reading of two pieces of text in these two presentation formats. Our analysis revealed that the text presentation format has a significant effect on reading behaviour. Rereading and regressions occurred significantly more often with the word-by-word format than with the letter-by-letter format. We also found a significant difference between the number of regressions starting at the words that end a sentence and that of regressions starting at all other words. The frequency of rereading was significantly higher for incorrectly typed or abbreviated words than for the other words. Analysis of the post-test questionnaire found almost equal acceptance of the word-by-word and letter-by-letter formats by the participants. A follow-up study with 18 hard-of-hearing participants showed a similar trend in results. The findings of this study highlight the importance of developing print interpreting tools that allow the interpreter and the client to choose the options that best facilitate the communication. They also bring up the need to develop new eye movement metrics for analysing the reading of dynamic text, and provide first results on a new dynamic presentation context.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Augmented Human Activities (AHA), School of Management (JKK)
Contributors: Sharmin, S., Špakov, O., Räihä, K. J.
Number of pages: 14
Pages: 17-30
Publication date: 2015
Peer-reviewed: Yes

Publication information

Journal: International Journal of Human-Computer Studies
Volume: 78
ISSN (Print): 1071-5819
Ratings: 
  • Scopus rating (2015): CiteScore 4.4 SJR 0.666 SNIP 1.739
Original language: English
ASJC Scopus subject areas: Human Factors and Ergonomics, Software, Education, Engineering(all), Human-Computer Interaction, Hardware and Architecture
Keywords: Dynamic text presentation, Eye movements, Print interpreting, Reading, Regressions
Source: Scopus
Source ID: 84923618729

Research output: Contribution to journalArticleScientificpeer-review

Reading on-screen text with gaze-based auto-scrolling

Visual information on eye movements can be used to facilitate scrolling while one is reading on-screen text. We carried out an experiment to find preferred reading regions on the screen and implemented an automatic scrolling technique based on the preferred regions of each individual reader. We then examined whether manual and automatic scrolling have an effect on reading behaviour on the basis of eye movement metrics, such as fixation duration and fixation count. We also studied how different font sizes affect the eye movement metrics. Results of analysis of data collected from 24 participants indicated no significant difference between manual and automatic scrolling in reading behaviour. Preferred reading regions on the screen varied among the participants. Most of them preferred relatively short regions. A significant effect of font size on fixation count was found. Subjective opinions indicated that participants found automatic scrolling convenient to use.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA)
Contributors: Sharmin, S., Špakov, O., Räihä, K. J.
Number of pages: 8
Pages: 24-31
Publication date: 2013

Host publication information

Title of host publication: Proceedings of the 2013 Conference on Eye Tracking South Africa, ETSA 2013
ISBN (Print): 9781450321105
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: automatic scrolling, eye movements, fixation count, fixation duration, manual scrolling, reading, reading region
Source: Scopus
Source ID: 84883884057

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Body-touching: An embodied interaction technique for health information systems in developing regions

We present a study of using embodied health information system for developing regions focusing on users not familiar with technology. We designed and developed a health information system with two gesture-based selection techniques: pointing to a screen and touching one's own body part. We evaluated the prototype in user study with 37 semi-literate and literate participants. Our results indicate a clear preference (76%) for touching in the healthcare domain. Based on our observations and user feedback, we present four design guidelines for developing embodied systems for the developing world: designing bodycentric interaction to overcome literacy and technological proficiency barriers, addressing the misconceptions of system behaviors with users not familiar with technology, understanding effects of cultural constraints on interaction, and utilizing interactive virtual avatars to connect with the users.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), IBM Research, Indian Institute of Technology
Contributors: Sharma, S., Srivastava, S., Sorathia, K., Hakulinen, J., Heimonen, T., Turunen, M., Rajput, N.
Number of pages: 8
Pages: 49-56
Publication date: 4 Nov 2014

Host publication information

Title of host publication: MINDTREK 2014 - Proceedings of the 18th International Academic MindTrek Conference: "Media Business, Management, Content and Services"
Publisher: Association for Computing Machinery, Inc
ISBN (Electronic): 9781450330060
ASJC Scopus subject areas: Computer Science Applications, Human-Computer Interaction, Software
Keywords: Body-centric interaction, Embodied interaction, gesture-based interaction, HCI4D, Health information systems, Information access
Source: Scopus
Source ID: 84964053943

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Farm detection based on deep convolutional neural nets and semi-supervised green texture detection using VIS-NIR satellite image

Farm detection using low resolution satellite images is an important topic in digital agriculture. However, it has not received enough attention compared to high-resolution images. Although high resolution images are more efficient for detection of land cover components, the analysis of low-resolution images are yet important due to the low-resolution repositories of the past satellite images used for timeseries analysis, free availability and economic concerns. The current paper addresses the problem of farm detection using low resolution satellite images. In digital agriculture, farm detection has significant role for key applications such as crop yield monitoring. Two main categories of object detection strategies are studied and compared in this paper; First, a two-step semi-supervised methodology is developed using traditional manual feature extraction and modelling techniques; the developed methodology uses the Normalized Difference Moisture Index (NDMI), Grey Level Co-occurrence Matrix (GLCM), 2-D Discrete Cosine Transform (DCT) and morphological features and Support Vector Machine (SVM) for classifier modelling. In the second strategy, high-level features learnt from the massive filter banks of deep Convolutional Neural Networks (CNNs) are utilised. Transfer learning strategies are employed for pretrained Visual Geometry Group Network (VGG-16) networks. Results show the superiority of the high-level features for classification of farm regions.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Electrical Engineering, Coventry University
Contributors: Sharifzadeh, S., Tata, J., Tan, B.
Number of pages: 9
Pages: 100-108
Publication date: 2019

Host publication information

Title of host publication: DATA 2019 - Proceedings of the 8th International Conference on Data Science, Technology and Applications
Publisher: SCITEPRESS
Editors: Hammoudi, S., Quix, C., Bernardino, J.
ISBN (Electronic): 9789897583773
ASJC Scopus subject areas: Hardware and Architecture, Information Systems, Software, Computer Networks and Communications
Keywords: Classification, Convolutional Neural Nets (CNNs), Digital Agriculture, Satellite Image, Supervised Feature Extraction
Electronic versions: 

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Silicon capillary gripper with self-alignment capability

This paper reports a novel capillary microgripper. The microgripper is fabricated from silicon using deep reactive ion etching and is designed to be especially suitable for self-alignment. The gripper is shown to retain its self-alignment capabilities even when the head of the gripper does not match the size of the component. This mechanism is analyzed using numerical simulations and tested in pick-and-place experiments using commercial laser diode components. The advantage of the capillary microgripper has been demonstrated in picking and aligning microchips from adhesive films, which requires substantial picking force.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Integrated Technologies for Tissue Engineering Research (ITTE), Department of Automation and Systems Technology, Aalto University
Contributors: Sariola, V., Liimatainen, V., Tolonen, T., Udd, R., Zhou, Q.
Number of pages: 6
Pages: 4098-4103
Publication date: 2011

Host publication information

Title of host publication: 2011 IEEE International Conference on Robotics and Automation, ICRA 2011
Article number: 5979980
ISBN (Print): 9781612843865
ASJC Scopus subject areas: Software, Artificial Intelligence, Control and Systems Engineering, Electrical and Electronic Engineering
Keywords: Capillary gripper, Micro/nano robots, Microhandling, Self-alignment
Source: Scopus
Source ID: 84871673357

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Exploiting suppliers' potential in construction innovations

There is a need to understand ways to enhance innovations in the construction industry. It is argued that suppliers have potential to develop new innovations, but they are largely neglected in earlier construction-related research. This research focuses on suppliers' role in construction innovations, and the aim of the research is to increase understanding of practices for exploiting suppliers' potential in that context. A qualitative, explanatory research strategy is employed in the context of construction industry in Finland. Eighteen interviews are conducted with contractors to discover experiences and practices related to suppliers' potential in construction innovations. The results reveal practices for exploiting supplier's potential in construction innovations. As a key contribution, the research shows that suppliers have an important role in construction innovation but exploitation of suppliers' potential is still rather underdeveloped.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research group: Center for Research on Operations Projects and Services, Industrial and Information Management
Contributors: Sariola, R.
Number of pages: 7
Pages: 678-684
Publication date: 2 Feb 2018

Host publication information

Title of host publication: 2017 International Conference on Engineering, Technology and Innovation : Engineering, Technology and Innovation Management Beyond 2020: New Challenges, New Approaches, ICE/ITMC 2017 - Proceedings
Publisher: IEEE
ISBN (Electronic): 9781538607749
ASJC Scopus subject areas: Computer Science Applications, Software, Engineering (miscellaneous), Computer Networks and Communications
Keywords: construction innovation, project networks, supplier management
Source: Scopus
Source ID: 85047528988

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

On Renyi's entropy estimation with one-dimensional Gaussian kernels

Rényi's entropies play a significant role in many signal processing applications. Plug-in kernel density estimation methods have been employed to estimate such entropies with good results. However, they become computationally intractable in higher dimensions, because of the requirement to store intermediate probability density values for a large number of data points. We propose a method to reduce the number of the samples in a plug-in kernel density estimation method for Rényi's entropies of real exponents and to improve the result of the standard plug-in kernel density method. To this end, we derive a univariate estimator, using an Hermite expansion of sums of Gaussian kernels and a hierarchical clustering of the samples. On simulated data from a univariate Gaussian distribution, our method performs better than a k-nearest neigbour algorithm and other kernel density estimation methods.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Signal Processing
Contributors: Sarbu, S.
Number of pages: 5
Pages: 4408-4412
Publication date: 18 May 2016

Host publication information

Title of host publication: 2016 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)
Publisher: IEEE
ISBN (Print): 9781479999880
ASJC Scopus subject areas: Signal Processing, Software, Electrical and Electronic Engineering
Keywords: Gaussian kernels, Hermite expansion, hierarchical clustering, Rényi's entropy estimation
Source: Scopus
Source ID: 84973308366

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Analysis of an efficient parallel implementation of active-set Newton algorithm

This paper presents an analysis of an efficient parallel implementation of the active-set Newton algorithm (ASNA), which is used to estimate the nonnegative weights of linear combinations of the atoms in a large-scale dictionary to approximate an observation vector by minimizing the Kullback–Leibler divergence between the observation vector and the approximation. The performance of ASNA has been proved in previous works against other state-of-the-art methods. The implementations analysed in this paper have been developed in C, using parallel programming techniques to obtain a better performance in multicore architectures than the original MATLAB implementation. Also a hardware analysis is performed to check the influence of CPU frequency and number of CPU cores in the different implementations proposed. The new implementations allow ASNA algorithm to tackle real-time problems due to the execution time reduction obtained.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Signal Processing, Research group: Audio research group - ARG, Universitat Politècnica de València
Contributors: San Juan Sebastián, P., Virtanen, T., Garcia-Molla, V. M., Vidal, A. M.
Number of pages: 12
Pages: 1298-1309
Publication date: Mar 2019
Peer-reviewed: Yes
Early online date: 19 May 2018

Publication information

Journal: Journal of Supercomputing
Volume: 75
Issue number: 3
ISSN (Print): 0920-8542
Ratings: 
  • Scopus rating (2019): CiteScore 3.9 SJR 0.432 SNIP 1.181
Original language: English
ASJC Scopus subject areas: Software, Theoretical Computer Science, Information Systems, Hardware and Architecture
Keywords: Convex optimization, Multicore, Newton algorithm, Parallel computing, Sparse representation
Source: Scopus
Source ID: 85047129085

Research output: Contribution to journalArticleScientificpeer-review

Mixed reality with multimodal head-mounted pico projector

Many kinds of displays can be used for augmented reality (AR). Multimodal head-mounted pico projector is a concept, which is little explored for AR. It opens new possibilities for wearable dis-plays. In this paper we present our proof-of-concept prototype of a multimodal head-mounted pico projector. Our main contributions are the display concept and some usage examples for it.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), University of Tampere
Contributors: Sand, A., Rakkolainen, I.
Publication date: 2013

Host publication information

Title of host publication: Proceedings of the Virtual Reality International Conference on Laval Virtual, VRIC 2013
Article number: 14
ISBN (Print): 9781450318754
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Augmented reality, Mixed reality, Multimodality, Pico projector, Wearable displays
Source: Scopus
Source ID: 84882277921

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

User generated soundscapes activating museum visitors

Museums are seeking various ways to attract and engage audience. Activities like virtual museums, mobile audio guides, augmented reality as well as interactive digital stories aim to provide interactive experiences for an audience with familiarity of digital interaction. Our target is to enable visitor's role change from a passive audience to an active participator as content creator. We concentrate on audio augmentation for museum context because audio provides another perspective into the content in question. In this paper, we discuss our experiences of bringing user generated soundscapes as a part of museums' activities by developing a soundscape platform and a number of mobile applications running on it. Most of the functionality is distributed as ease of use and intuitive mobile applications, which have been evaluated in real context in two workshops. The workshops had different user groups and goals. The first one evaluated ease of use and feelings evoked of the young audiences, and the second one ease of use and acceptance of use for other museums than the Museum of Technology, which was our primary design environment. Copyright is held by the owner/author(s).

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Helsinki Metropolia University of Applied Sciences
Contributors: Salo, K., Bauters, M., Mikkonen, T.
Number of pages: 8
Pages: 220-227
Publication date: 3 Apr 2017

Host publication information

Title of host publication: 32nd Annual ACM Symposium on Applied Computing, SAC 2017
Publisher: ACM
ISBN (Electronic): 9781450344869
ASJC Scopus subject areas: Software
Keywords: Android, Audio Augmented Reality, Engagement, Mobile Sound mixing, Participatory design, Research-based design, Soundscape, User centered design, User generated content
Source: Scopus
Source ID: 85020887194

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Modular audio story platform for museums

Museums are seeking different ways to attract and engage audiences. Digital stories in various forms have been utilized as one approach to increase audience experience. This paper presents how to bring audio stories as a part of museum's activities by developing a modular audio story platform. Most of the functionality is included in Android applications, which allow visitors to attach stories with emotions to artifacts, share stories with other visitors and enrich existing stories with sounds. All the audio files, linking of the artifacts and related audio files are managed by audio digital asset management system. Our platform supports curated audio stories, but the main emphasis is in the visitors' audio stories. We differentiate from the other digital storytelling systems by attaching emotions onto the visitor stories, and combining the soundscapes and audio stories as visitor modified audio stories. Copyright is held by the owner/author(s).

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Helsinki Metropolia University of Applied Sciences, University of Helsinki
Contributors: Salo, K., Zinin, V., Bauters, M., Mikkonen, T.
Number of pages: 4
Pages: 113-116
Publication date: 7 Mar 2017

Host publication information

Title of host publication: IUI 2017 - Companion of the 22nd International Conference on Intelligent User Interfaces
Publisher: ACM
ISBN (Electronic): 9781450348935
ASJC Scopus subject areas: Software, Human-Computer Interaction
Keywords: Android, Audio story, Emotions, Mobile Sound mixing, Museum, Soundscape, User generated content
Source: Scopus
Source ID: 85016642268

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Games and energy: Profiling power usage during play

Computer gaming is a globally growing industry, with hundreds of millions of gaming-capable computers consuming an ever increasing amount of energy. Several of the world's most popular computer games tend to make a heavy use of computers' central processing units and/or graphics processing units. When such games execute on typical computers, for much of the time those components are kept in high energy-consuming states, regardless of what is happening in the game. We analyze this pattern of energy usage and we assess the scope for economizing on energy. The results presented also give insight into the energy implications of the hardware platform and operating systems used for hosting such games. We use the results to provide practical suggestions to both the industry and the gamers. Copyright is held by the owner/author(s). Publication rights licensed to ACM.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Mathematical modelling with wide societal impact (MathImpact), European Organization for Nuclear Research
Contributors: Salmela, J. M., Thanisch, P., Sotamaa, O., Niemi, T.
Number of pages: 8
Pages: 192-199
Publication date: 4 Nov 2014

Host publication information

Title of host publication: MINDTREK 2014 - Proceedings of the 18th International Academic MindTrek Conference: "Media Business, Management, Content and Services"
Publisher: Association for Computing Machinery, Inc
ISBN (Electronic): 9781450330060
ASJC Scopus subject areas: Computer Science Applications, Human-Computer Interaction, Software
Keywords: Computer games, Energy measurement
Source: Scopus
Source ID: 84963995284

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Electroplated nickel microspring and low-friction precision linear slider: A novel micro-force sensing tool

This paper introduces a novel micro-force sensing approach utilizing an electroplated nickel microspring and a precision linear slider (PLS) for micro-tensile testing applications. After investigating the effects of friction forces in a PLS, an electroplated nickel microspring is designed, fabricated and integrated into the PLS, and the proposed micro-force sensor concept is validated through experimental results. The microspring fabricated in this paper is limited to forces up to 6 mN with the average sensitivity of 36.63 μN/μm. It is shown that the friction forces introduce uncertainties only to the forces less than 500 μN. The proposed approach allows the fabrication of micro-force sensors for the force ranges of up to tens of Millinewtons for different applications.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Automation Science and Engineering, Integrated Technologies for Tissue Engineering Research (ITTE), Key Laboratory for Thin Film and Microfabrication Technology, Research Institute of Micro/Nano Science and Technology, Ministry of Education China
Contributors: Saketi, P., Wangyang, P., Li, H., Wang, Q., Kallio, P.
Number of pages: 6
Pages: 2679-2684
Publication date: 29 Jun 2015

Host publication information

Title of host publication: 2015 IEEE International Conference on Robotics and Automation (ICRA), 26-30 May 2015,Seattle, WA
ISBN (Print): 9781479969241
ASJC Scopus subject areas: Software, Artificial Intelligence, Control and Systems Engineering, Electrical and Electronic Engineering
Source: Scopus
Source ID: 84938220720

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Conversion of sparsely-captured light field into alias-free fullparallax multiview content

We propose shearlet decomposition based light field (LF) reconstruction and filtering techniques for mitigating artifacts in the visualized contents of 3D multiview displays. Using the LF reconstruction capability, we first obtain the densely sampled light field (DSLF) of the scene from a sparse set of view images. We design the filter via tiling the Fourier domain of epipolar image by shearlet atoms that are directionally and spatially localized versions of the desired display passband. In this way, it becomes possible to process the DSLF in a depth-dependent manner. That is, the problematic areas in the 3D scene that are outside of the display depth of field (DoF) can be selectively filtered without sacrificing high details in the areas near the display, i.e. inside the DoF. The proposed approach is tested on a synthetic scene and the improvements achieved by means of the quality of the visualized content are verified, where the visualization process is simulated using a geometrical optics model of the human eye.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing, Electronics and Telecommunication Research Institute (ETRI)
Contributors: Sahin, E., Vagharshakyan, S., Bregovic, R., Lee, G., Gotchev, A.
Number of pages: 5
Pages: 1441-1445
Publication date: 2018

Host publication information

Title of host publication: Electronic Imaging : Stereoscopic Displays and Applications XXIX
Publisher: Society for Imaging Science and Technology
ASJC Scopus subject areas: Computer Graphics and Computer-Aided Design, Computer Science Applications, Human-Computer Interaction, Software, Electrical and Electronic Engineering, Atomic and Molecular Physics, and Optics

Bibliographical note

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Source: Scopus
Source ID: 85052854954

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Code notes: Designing a low-cost tangible coding tool for/with children

Programming has become an essential subject for today's education curriculum and as a result, the importance of creating the right environments to teach is increasing. For such environments, featuring tangible tools enhances creativity and collaboration. However, due to their high prices, current tangible tools are not reachable by most of the students. We developed Code Notes as a low-cost, attainable and tangible tool aimed to motivate children to support programming education. Code Notes is comprised of an Android app and code-cardboards to teach the basic concepts in programming. We continue to develop the platform with insights gained from children. This paper shares the design phases of Code Notes and observations from our two-month programming project. We also presented some future concepts of Code Notes that offer an active and embodied interaction with the teaching material.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Koç University
Contributors: Sabuncuoǧlu, A., Erkaya, M., Buruk, O. T., Göksun, T.
Number of pages: 6
Pages: 644-649
Publication date: 19 Jun 2018

Host publication information

Title of host publication: IDC 2018 - Proceedings of the 2018 ACM Conference on Interaction Design and Children
Publisher: ACM
ISBN (Electronic): 9781450351522
ASJC Scopus subject areas: Developmental and Educational Psychology, Education, Software, Human-Computer Interaction
Keywords: Affordable systems for education, Collaborative learning environments, Mobile learning, Tangible blocks.
Source: Scopus
Source ID: 85051492885

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Scinet: Interactive intent modeling for information discovery

Current search engines offer limited assistance for exploration and information discovery in complex search tasks. Instead, users are distracted by the need to focus their cognitive efforts on finding navigation cues, rather than selecting relevant information. Interactive intent modeling enhances the human information exploration capacity through computational modeling, visualized for interaction. Interactive intent modeling has been shown to increase task-level information seeking performance by up to 100%. In this demonstration, we showcase SciNet, a system implementing interactive intent modeling on top of a scientific article database of over 60 million documents.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research Community on Data-to-Decision (D2D), Aalto University, School of Management (JKK), University of Helsinki
Contributors: Ruotsalo, T., Peltonen, J., Eugster, M. J. A., Glowacka, D., Reijonen, A., Jacucci, G., Myllymäki, P., Kaski, S.
Number of pages: 2
Pages: 1043-1044
Publication date: 9 Aug 2015

Host publication information

Title of host publication: SIGIR 2015 - Proceedings of the 38th International ACM SIGIR Conference on Research and Development in Information Retrieval
Publisher: Association for Computing Machinery, Inc
ISBN (Electronic): 9781450336215
ASJC Scopus subject areas: Information Systems, Software
Keywords: Intent modeling, Interactive information retrieval, Personalization, Visual information seeking
Source: Scopus
Source ID: 84953776151

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

IntentRadar: Search user interface that anticipates user's search intents

We introduce IntentRadar, an interactive search user interface that anticipates user's search intents by estimating them from user interaction. The estimated intents are represented as keywords and visualized on a radial layout that organizes the keywords as directions in the information space. IntentRadar assists users to direct their search by allowing to target relevance feedback on keywords by manipulating the position of the keywords on the radar. The system then learns and visualizes improved estimates of intents and retrieves documents corresponding to the present search intent estimate. IntentRadar has been shown to significantly improve users' task performance and the quality of retrieved information without compromising task execution time.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research Community on Data-to-Decision (D2D), Aalto University, University of Helsinki
Contributors: Ruotsalo, T., Peltonen, J., Eugster, M. J. A., Glowacka, D., Reijonen, A., Jacucci, G., Myllymäki, P., Kaski, S.
Number of pages: 4
Pages: 455-458
Publication date: 2014

Host publication information

Title of host publication: CHI EA 2014: One of a ChiNd - Extended Abstracts, 32nd Annual ACM Conference on Human Factors in Computing Systems
Publisher: Association for Computing Machinery
ISBN (Print): 9781450324748
ASJC Scopus subject areas: Human-Computer Interaction, Computer Graphics and Computer-Aided Design, Software
Keywords: Intent modeling, Interactive information retrieval, Search user interfaces, Visualization
Source: Scopus
Source ID: 84900560093

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Exploring the use of deprecated PHP releases in the wild internet: Still a LAMP issue?

Many web sites utilize deprecated software products that are no longer maintained by the associated software producers. This paper explores the question of whether an existing big data collection can be used to predict the likelihood of deprecated PHP releases based on different abstract components in modern web deployment stacks. Building on web intelligence, software security, and data-based industry rationales, the question is examined by focusing on the most popular domains in the contemporary web-facing Internet. Logistic regression is used for classification. Although statistical classification performance is modest, the results indicate that deprecated PHP releases are associated with Linux and other open source software components. Geographical variation is small. Besides these results, the paper contributes to the web intelligence research by evaluating the feasibility of existing big data collections for mass-scale fingerprinting.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: University of Turku, Department of Information Technology
Contributors: Ruohonen, J., Hyrynsalmi, S., Leppänen, V.
Publication date: 13 Jun 2016

Host publication information

Title of host publication: 6th International Conference on Web Intelligence, Mining and Semantics, WIMS 2016
Publisher: Association for Computing Machinery
Article number: 26
ISBN (Electronic): 9781450340564
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Cyber security, Patching, Release engineering, Web crawling
Source: Scopus
Source ID: 84978522051

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Trading exploits online: A preliminary case study

A software defect that exposes a software system to a cyber security attack is known as a software vulnerability. A software security exploit is an engineered software solution that successfully exploits the vulnerability. Exploits are used to break into computer systems, but exploits are currently used also for security testing, security analytics, intrusion detection, consultation, and other legitimate and legal purposes. A well-established market emerged in the 2000s for software vulnerabilities. The current market segments populated by small and medium-sized companies exhibit signals that may eventually lead to a similar industrialization of software exploits. To these ends and against these industry trends, this paper observes the first online market place for trading exploits between buyers and sellers. The paper adopts three different perspectives to study the case. The paper (a) portrays the studied exploit market place against the historical background in the software security industry. A qualitative assessment is made to (b) evaluate the case against the common characteristics of traditional online market places. The qualitative observations are used in the quantitative part (c) for predicting the price of exploits with partial least squares regression. The results show that (i) the case is unique from a historical perspective, although (ii) the online market place characteristics are familiar. The regression estimates also indicate that (iii) the pricing of exploits is only partially dependent on such factors as the targeted platform, the date of disclosure of the exploited vulnerability, and the quality assurance service provided by the market place provider. The results allow to contemplate (iv) practical means for enhancing the market place.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: University of Turku, Department of Information Technology
Contributors: Ruohonen, J., Hyrynsalmi, S., Leppänen, V.
Publication date: 23 Aug 2016

Host publication information

Title of host publication: IEEE RCIS 2016 - IEEE 10th International Conference on Research Challenges in Information Science
Publisher: IEEE COMPUTER SOCIETY PRESS
ISBN (Electronic): 9781479987092
ASJC Scopus subject areas: Computer Science Applications, Information Systems, Software
Keywords: attack code, cyber security, e-commerce, offensive security, penetration testing, software vulnerability
Source: Scopus
Source ID: 84987653537

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Time series trends in software evolution

Background The laws of software evolution were formulated to describe time series trends in software over time. Objective Building on econometrics, the paper relates the laws theoretically to the concept of stationarity. The theoretical argumentation builds on the fact that in a stationary time series, the mean and variance remain constant. The concept is further elaborated with different statistical types of time series trends. These provide the objective for the empirical experiment that evaluates whether software size measures in a typical software evolution dataset are stationary. Method The time series analysis is based on conventional statistical tests for the evaluation of stationarity. Results The empirical dataset contains time series extracted from the version control systems used in Vaadin and Tomcat between circa 2006 and 2013. The results establish that the observed time series are neither stationary nor follow simple mathematical functions that would translate into stationarity. Conclusion The testing framework presented in the paper allows evaluating the stationarity of software evolution time series. The results can be interpreted theoretically against the laws of software evolution. These methodological and theoretical contributions improve the foundations of predictive time series modeling of software evolution problems.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Managing digital industrial transformation (mDIT), University of Turku, Department of Management and Entrepreneurship, Turun Kauppakorkeakoulu
Contributors: Ruohonen, J., Hyrynsalmi, S., Leppänen, V.
Number of pages: 26
Pages: 990-1015
Publication date: 1 Dec 2015
Peer-reviewed: Yes

Publication information

Journal: Journal of Software: Evolution and Process
Volume: 27
Issue number: 12
ISSN (Print): 2047-7473
Original language: English
ASJC Scopus subject areas: Software
Keywords: dynamic regression, software evolution, stationarity, time series analysis, unit roots
Source: Scopus
Source ID: 84955628781

Research output: Contribution to journalArticleScientificpeer-review

Exploring the Stability of Software with Time-Series Cross-Sectional Data

The stability of software is a classical topic in software engineering. This research investigates stability of software architectures in terms of an object-oriented design principle presented by Robert C. Martin. The research approach is statistical: the design principle is evaluated with a time-series cross-sectional (TSCS) regression model. The empirical sample covers a release history from the Java library Vaadin. The empirical results establish that the design principle cannot be used to characterize the library. Besides delivering this negative empirical result, the research provides the necessary methodological background that is required to understand TSCS modeling.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Managing digital industrial transformation (mDIT), University of Turku, Department of Information Technology
Contributors: Ruohonen, J., Hyrynsalmi, S., Leppänen, V.
Number of pages: 7
Pages: 41-47
Publication date: 31 Jul 2015

Host publication information

Title of host publication: Proceedings - 2nd International Workshop on Software Architecture and Metrics, SAM 2015
Publisher: Institute of Electrical and Electronics Engineers Inc.
ISBN (Electronic): 9781479919345
ASJC Scopus subject areas: Hardware and Architecture, Software
Keywords: panel data, software metrics, software stability
Source: Scopus
Source ID: 84946921946

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Software evolution and time series volatility: An empirical exploration

The paper presents the first empirical study to examine econometric time series volatility modeling in the software evolution context. The econometric volatility concept is related to the conditional variance of a time series rather than the conditional mean targeted in conventional regression analysis. The software evolution context is motivated by relating these variance characteristics to the proximity of operating system releases, the theoretical hypothesis being that volatile characteristics increase nearby new milestone releases. The empirical experiment is done with a case study of FreeBSD. The analysis is carried out with 12 time series related to bug tracking, development activity, and communication. A historical period from 1995 to 2011 is covered under a daily sampling frequency. According to the results the time series dataset contains visible volatility characteristics, but these cannot be explained by the time windows around the six observed major FreeBSD releases. The paper consequently contributes to the software evolution research field with new methodological ideas, as well as with both positive and negative empirical results.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Managing digital industrial transformation (mDIT), University of Turku, Department of Information Technology
Contributors: Ruohonen, J., Hyrynsalmi, S., Leppänen, V.
Number of pages: 10
Pages: 56-65
Publication date: 30 Aug 2015

Host publication information

Title of host publication: 14th International Workshop on Principles of Software Evolution, IWPSE 2015 - Proceedings
Volume: 30-Aug-2015
Publisher: Institute of Electrical and Electronics Engineers Inc.
ISBN (Electronic): 9781450338165
ASJC Scopus subject areas: Software, Computational Theory and Mathematics, Modelling and Simulation, Theoretical Computer Science
Keywords: ARIMA, Code churn, Conditional variance, FreeBSD, GARCH, Software evolution, Time series analysis, Volatility
Source: Scopus
Source ID: 84958599161

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Is Texture Denoising Efficiency Predictable?

Images of different origin contain textures, and textural features in such regions are frequently employed in pattern recognition, image classification, information extraction, etc. Noise often present in analyzed images might prevent a proper solution of basic tasks in the aforementioned applications and is worth suppressing. This is not an easy task since even the most advanced denoising methods destroy texture in a more or less degree while removing noise. Thus, it is desirable to predict the filtering behavior before any denoising is applied. This paper studies the efficiency of texture image denoising for different noise intensities and several filter types under different visual quality criteria (quality metrics). It is demonstrated that the most efficient existing filters provide very similar results. From the obtained results, it is possible to generalize and employ the prediction strategy earlier proposed for denoising techniques based on the discrete cosine transform. Accuracy of such a prediction is studied and the ways to improve it are considered. Some practical recommendations concerning a decision to undertake whether it is worth applying a filter are given.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Signal Processing, Research group: Computational Imaging-CI
Contributors: Rubel, O., Lukin, V., Abramov, S., Vozel, B., Pogrebnyak, O., Egiazarian, K.
Publication date: 2018
Peer-reviewed: Yes

Publication information

Journal: International Journal of Pattern Recognition and Artificial Intelligence
Volume: 32
Issue number: 1
Article number: 1860005
ISSN (Print): 0218-0014
Ratings: 
  • Scopus rating (2018): CiteScore 2.2 SJR 0.304 SNIP 0.718
Original language: English
ASJC Scopus subject areas: Software, Computer Vision and Pattern Recognition, Artificial Intelligence
Keywords: image processing, noise suppression, Texture denoising, visual quality
Electronic versions: 
Source: Scopus
Source ID: 85025804856

Research output: Contribution to journalArticleScientificpeer-review

Making the cloud work for software producers: Linking architecture, operating cost and revenue

Cloud migration is concerned with moving an on-premise software system into the cloud. In this paper, we focus on software producers adopting the cloud to provide their solutions to enterprise customers. Their challenge is to migrate a software product, developed in-house and traditionally delivered on-premise, to an Infrastructure-as-a-Service or Platform-as-a-Service solution, while also mapping an existing traditional licensing model on to a cloud monetization model. The analysis of relevant cost types and factors of cloud computing generate relevant information for the software producers when deciding to adopt cloud computing, and defining software pricing. We present an integrated framework for informing cloud monetization based on operational cost factors for migrating to the cloud and test it in a real-life case study. Differences between basic virtualization of the software product and using fully cloud-native platform services for re-architecting the product in question are discussed.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Dublin City University, Free University of Bolzano-Bozen, Human-Centered Technology (IHTE)
Contributors: Rosati, P., Fowley, F., Pahl, C., Taibi, D., Lynn, T.
Number of pages: 12
Pages: 364-375
Publication date: 2018

Host publication information

Title of host publication: CLOSER 2018 - Proceedings of the 8th International Conference on Cloud Computing and Services Science
Publisher: SCITEPRESS
ISBN (Electronic): 9789897582950
ASJC Scopus subject areas: Computer Science (miscellaneous), Software, Computer Science Applications
Keywords: Architecture migration, Cloud migration, Monetization, Software producer, Total cost of ownership
Source: Scopus
Source ID: 85048894202

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

High-performance SIMD implementation of the lattice-Boltzmann method on the Xeon Phi processor

We present a high-performance implementation of the lattice-Boltzmann method (LBM) on the Knights Landing generation of Xeon Phi. The Knights Landing architecture includes 16GB of high-speed memory (MCDRAM) with a reported bandwidth of over 400 GB/s, and a subset of the AVX-512 single instruction multiple data (SIMD) instruction set. We explain five critical implementation aspects for high performance on this architecture: (1) the choice of appropriate LBM algorithm, (2) suitable data layout, (3) vectorization of the computation, (4) data prefetching, and (5) running our LBM simulations exclusively from the MCDRAM. The effects of these implementation aspects on the computational performance are demonstrated with the lattice-Boltzmann scheme involving the D3Q19 discrete velocity set and the TRT collision operator. In our benchmark simulations of fluid flow through porous media, using double-precision floating-point arithmetic, the observed performance exceeds 960 million fluid lattice site updates per second.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Physics, CSC - IT center for science, Abo Akad Univ, Abo Akademi University, Dept Phys, Jyväskylän yliopisto
Contributors: Robertsén, F., Mattila, K., Westerholm, J.
Number of pages: 16
Publication date: 10 Jul 2019
Peer-reviewed: Yes

Publication information

Journal: Concurrency Computation
Volume: 31
Issue number: 13
Article number: e5072
ISSN (Print): 1532-0626
Ratings: 
  • Scopus rating (2019): CiteScore 3.4 SJR 0.341 SNIP 0.944
Original language: English
ASJC Scopus subject areas: Software, Theoretical Computer Science, Computer Science Applications, Computer Networks and Communications, Computational Theory and Mathematics
Keywords: Lattice Boltzmann, prefetching, SIMD, Xeon Phi
Source: Scopus
Source ID: 85056764195

Research output: Contribution to journalArticleScientificpeer-review

A comparison of security assurance support of agile software development methods

Agile methods increase the speed and reduce the cost of software projects; however, they have been criticized for lack of documentation, traditional quality control, and, most importantly, lack of security assurance - mostly due to their informal and self-organizing approach to software development. This paper clarifies the requirements for security assurance by using an evaluation framework to analyze the compatibility of established agile security development methods: XP, Scrum and Kanban, combined with Microsoft SDL security framework, against Finland's established national security regulation (Vahti). We also analyze the selected methods based on their role definitions, and provide some avenues for future research.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Managing digital industrial transformation (mDIT), University of Turku, Department of Information Technology
Contributors: Rindell, K., Hyrynsalmi, S., Leppänen, V.
Number of pages: 8
Pages: 61-68
Publication date: 25 Jun 2015

Host publication information

Title of host publication: Computer Systems and Technologies - 16th International Conference, CompSysTech 2015: Proceedings
Volume: 1008
Publisher: Association for Computing Machinery
ISBN (Electronic): 9781450333573
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: DESMET, Kanban, Scrum, SDL, Secure agile development, Security assurance, Vahti, XP
Source: Scopus
Source ID: 84957689583

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Generative part-based Gabor object detector

Discriminative part-based models have become the approach for visual object detection. The models learn from a large number of positive and negative examples with annotated class labels and location (bounding box). In contrast, we propose a part-based generative model that learns from a small number of positive examples. This is achieved by utilizing "privileged information", sparse class-specific landmarks with semantic meaning. Our method uses bio-inspired complex-valued Gabor features to describe local parts. Gabor features are transformed to part probabilities by unsupervised Gaussian Mixture Model (GMM). GMM estimation is robustified for a small amount of data by a randomization procedure inspired by random forests. The GMM framework is also used to construct a probabilistic spatial model of part configurations. Our detector is invariant to translation, rotation and scaling. On part level invariance is achieved by pose quantization which is more efficient than previously proposed feature transformations. In the spatial model, invariance is achieved by mapping parts to an "aligned object space". Using a small number of positive examples our generative method performs comparably to the state-of-the-art discriminative method.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Signal Processing, Research group: Vision, Field robotics for efficient work sites (FIRE), Prostate cancer research center (PCRC), Lappeenranta University of Technology
Contributors: Riabchenko, E., Kämäräinen, J.
Number of pages: 8
Pages: 1-8
Publication date: 15 Dec 2015
Peer-reviewed: Yes

Publication information

Journal: Pattern Recognition Letters
Volume: 68
Issue number: P1
ISSN (Print): 0167-8655
Ratings: 
  • Scopus rating (2015): CiteScore 5.1 SJR 0.95 SNIP 2.002
Original language: English
ASJC Scopus subject areas: Software, Artificial Intelligence, Computer Vision and Pattern Recognition, Signal Processing
Keywords: Gabor feature, Gaussian mixture model, Generative learning, Object detection, Visual classification

Bibliographical note

EXT="Riabchenko, Ekaterina"

Source: Scopus
Source ID: 84941570575

Research output: Contribution to journalArticleScientificpeer-review

Patterns for safety system bus architecture

Traditionally safety and controls systems have been strictly separated from each other. There are both benefits and liabilities in this approach. Thus, modern system employing control and safety system parts do not necessarily make a strict separation between these two elements of the system. Regardless of the degree of separation, the nodes belonging to either control or safety system may need to communicate with each other to implement the desired functionality. An increasing number of systems nowadays utilize a fieldbus to connect the distributed nodes of the system together. A time comes in the design process, when one needs to select the architecture of the physical fieldbus. That is, how and which nodes are connected? In this paper, two patterns to organize the fieldbus architecture are illustrated. In short, one either can separate the fieldbus between the safety and control system nodes or use a shared fieldbus between the nodes.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research area: Information Systems in Automation, Automation and Hydraulic Engineering
Contributors: Rauhamäki, J.
Publication date: 7 Apr 2016

Host publication information

Title of host publication: Proceedings of the 10th Travelling Conference on Pattern Languages of Programs, VikingPLoP 2016
Publisher: ACM
Article number: a4
ISBN (Electronic): 9781450342001
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Communication, Control system, Fieldbus, Safety system, Separated, Shared
Source: Scopus
Source ID: 85015687535

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Robotic process automation - Creating value by digitalizing work in the private healthcare?

Organizations are applying digitalization to the constantly increasing amounts of different organizational processes [2]. The healthcare sector is also changing and actively seeking better ways to enhance performance, especially in the private healthcare sector [7]. Automation of workflow processes, e.g., Robotic Process Automation (RPA), in organizations has been emerging as a solution to this demand [3, 4]. To meet this clear demand, automation of workflow processes in organizations has been a rising trend during the past few years [3]. We analyze the value creating functions of the RPA potential in the private healthcare industry sector, using modified Walter et al.’s function-oriented value analysis as our theoretical lens for identifying the potential of RPA.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Industrial and Information Management
Contributors: Ratia, M., Myllärniemi, J., Helander, N.
Number of pages: 6
Pages: 222-227
Publication date: 10 Oct 2018

Host publication information

Title of host publication: Mindtrek 2018 - Proceedings of the 22nd International Academic Mindtrek Conference
Publisher: ACM
ISBN (Electronic): 9781450365895
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Digitalization of knowledge work, Healthcare, Robotic Process Automation, Value creation
Source: Scopus
Source ID: 85056714767

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Automatic word count estimation from daylong child-centered recordings in various language environments using language-independent syllabification of speech

Automatic word count estimation (WCE) from audio recordings can be used to quantify the amount of verbal communication in a recording environment. One key application of WCE is to measure language input heard by infants and toddlers in their natural environments, as captured by daylong recordings from microphones worn by the infants. Although WCE is nearly trivial for high-quality signals in high-resource languages, daylong recordings are substantially more challenging due to the unconstrained acoustic environments and the presence of near- and far-field speech. Moreover, many use cases of interest involve languages for which reliable ASR systems or even well-defined lexicons are not available. A good WCE system should also perform similarly for low- and high-resource languages in order to enable unbiased comparisons across different cultures and environments. Unfortunately, the current state-of-the-art solution, the LENA system, is based on proprietary software and has only been optimized for American English, limiting its applicability. In this paper, we build on existing work on WCE and present the steps we have taken towards a freely available system for WCE that can be adapted to different languages or dialects with a limited amount of orthographically transcribed speech data. Our system is based on language-independent syllabification of speech, followed by a language-dependent mapping from syllable counts (and a number of other acoustic features) to the corresponding word count estimates. We evaluate our system on samples from daylong infant recordings from six different corpora consisting of several languages and socioeconomic environments, all manually annotated with the same protocol to allow direct comparison. We compare a number of alternative techniques for the two key components in our system: speech activity detection and automatic syllabification of speech. As a result, we show that our system can reach relatively consistent WCE accuracy across multiple corpora and languages (with some limitations). In addition, the system outperforms LENA on three of the four corpora consisting of different varieties of English. We also demonstrate how an automatic neural network-based syllabifier, when trained on multiple languages, generalizes well to novel languages beyond the training data, outperforming two previously proposed unsupervised syllabifiers as a feature extractor for WCE.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences, Aalto University, Laboratoire de Sciences Cognitives et Psycholinguistique, Carnegie Mellon University, University of Manitoba, Max Planck Institute for Psycholinguistics, CONICET, Duke University
Contributors: Räsänen, O., Seshadri, S., Karadayi, J., Riebling, E., Bunce, J., Cristia, A., Metze, F., Casillas, M., Rosemberg, C., Bergelson, E., Soderstrom, M.
Number of pages: 18
Pages: 63-80
Publication date: 1 Oct 2019
Peer-reviewed: Yes

Publication information

Journal: Speech Communication
Volume: 113
ISSN (Print): 0167-6393
Ratings: 
  • Scopus rating (2019): CiteScore 4.2 SJR 0.554 SNIP 1.297
Original language: English
ASJC Scopus subject areas: Software, Modelling and Simulation, Communication, Language and Linguistics, Linguistics and Language, Computer Vision and Pattern Recognition, Computer Science Applications
Keywords: Automatic syllabification, Daylong recordings, Language acquisition, Noise robustness, Word count estimation
Electronic versions: 
Source: Scopus
Source ID: 85070952723

Research output: Contribution to journalArticleScientificpeer-review

Haptic feedback of gaze gestures with glasses: Localization accuracy and effectiveness

Wearable devices including smart eyewear require new interaction methods between the device and the user. In this paper, we describe our work on the combined use of eye tracking for input and haptic (touch) stimulation for output with eyewear. Input with eyes can be achieved by utilizing gaze gestures which are predefined patterns of gaze movements identified as commands. The frame of the eyeglasses offers three natural contact points with the wearer's skin for haptic stimulation. The results of two user studies reported in this paper showed that stimulation moving between the contact points was easy for users to localize, and that the stimulation has potential to make the use of gaze gestures more efficient.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), University of Tampere
Contributors: Rantala, J., Kangas, J., Isokoski, P., Akkil, D., Špakov, O., Raisamo, R.
Number of pages: 8
Pages: 855-862
Publication date: 7 Sep 2015

Host publication information

Title of host publication: UbiComp and ISWC 2015 - Proceedings of the 2015 ACM International Joint Conference on Pervasive and Ubiquitous Computing and the Proceedings of the 2015 ACM International Symposium on Wearable Computers
Publisher: Association for Computing Machinery, Inc
ISBN (Electronic): 9781450335751
ASJC Scopus subject areas: Computer Networks and Communications, Hardware and Architecture, Software
Keywords: Gaze gestures, Gaze tracking, Haptic stimulation, Haptics, Pervasive computing, Smart eyewear, Smart glasses, Wearable computing
Source: Scopus
Source ID: 84962523895

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Glasses with haptic feedback of gaze gestures

We introduce eyeglasses that present haptic feedback when using gaze gestures for input. The glasses utilize vibrotactile actuators to provide gentle stimulation to three locations on the user's head. We describe two initial user studies that were conducted to evaluate the easiness of recognizing feedback locations and participants' preferences for combining the feedback with gaze gestures. The results showed that feedback from a single actuator was the easiest to recognize and also preferred when used with gaze gestures. We conclude by presenting future use scenarios that could benefit from gaze gestures and haptic feedback.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), School of Management (JKK)
Contributors: Rantala, J., Isokoski, P., Kangas, J., Raisamo, R., Akkil, D.
Number of pages: 6
Pages: 1597-1602
Publication date: 2014

Host publication information

Title of host publication: CHI EA 2014: One of a ChiNd - Extended Abstracts, 32nd Annual ACM Conference on Human Factors in Computing Systems
Publisher: Association for Computing Machinery
ISBN (Print): 9781450324748
ASJC Scopus subject areas: Human-Computer Interaction, Computer Graphics and Computer-Aided Design, Software
Keywords: Gaze gestures, Gaze input, Haptics, Vibrotactile feedback, Wearable computing
Source: Scopus
Source ID: 84900557759

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Touch gestures in communicating emotional intention via vibrotactile stimulation

Remote communication between people typically relies on audio and vision although current mobile devices are increasingly based on detecting different touch gestures such as swiping. These gestures could be adapted to interpersonal communication by using tactile technology capable of producing touch stimulation to a user's hand. It has been suggested that such mediated social touch would allow for new forms of emotional communication. The aim was to study whether vibrotactile stimulation that imitates human touch can convey intended emotions from one person to another. For this purpose, devices were used that converted touch gestures of squeeze and finger touch to vibrotactile stimulation. When one user squeezed his device or touched it with finger(s), another user felt corresponding vibrotactile stimulation on her device via four vibrating actuators. In an experiment, participant dyads comprising a sender and receiver were to communicate variations in the affective dimensions of valence and arousal using the devices. The sender's task was to create stimulation that would convey unpleasant, pleasant, relaxed, or aroused emotional intention to the receiver. Both the sender and receiver rated the stimulation using scales for valence and arousal so that the match between sender's intended emotions and receiver's interpretations could be measured. The results showed that squeeze was better at communicating unpleasant and aroused emotional intention, while finger touch was better at communicating pleasant and relaxed emotional intention. The results can be used in developing technology that enables people to communicate via touch by choosing touch gesture that matches the desired emotion.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Augmented Human Activities (AHA), Field robotics for efficient work sites (FIRE)
Contributors: Rantala, J., Salminen, K., Raisamo, R., Surakka, V.
Number of pages: 12
Pages: 679-690
Publication date: 2013
Peer-reviewed: Yes

Publication information

Journal: International Journal of Human-Computer Studies
Volume: 71
Issue number: 6
ISSN (Print): 1071-5819
Ratings: 
  • Scopus rating (2013): CiteScore 4.6 SJR 0.861 SNIP 2.378
Original language: English
ASJC Scopus subject areas: Human Factors and Ergonomics, Software, Education, Engineering(all), Human-Computer Interaction, Hardware and Architecture
Keywords: Affective interaction, Emotions, Haptics, Mediated social touch, Mobile devices, Tactile communication
Source: Scopus
Source ID: 84876589281

Research output: Contribution to journalArticleScientificpeer-review

Casual immersive viewing with smartphones

In this paper, we explore how to better integrate virtual reality viewing to a smartphone. We present novel designs for casual (short-term) immersive viewing of spatial and 3D content, such as augmented and virtual reality, with smartphones. Our goal is to create a simple and low-cost casual-viewing design which could be retrofitted and eventually be embedded into smartphones, instead of using larger spatial viewing accessories. We explore different designs and implemented several prototypes. One prototype uses thin and light near-to-eye optics with a smartphone display, thus providing the user with the functionality of a large, high-resolution virtual display. Our designs also enable 3D user interfaces. Easy interaction through various gestures and other modalities is possible by using the inertial and other sensors and camera of the smartphone. Our preliminary concepts are a starting point for exploring useful constructions and designs for such usage.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Electronics and Communications Engineering, Research group: Personal Electronics Group, University of California, Santa Barbara
Contributors: Rakkolainen, I., Raisamo, R., Turk, M., Höllerer, T., Palovuori, K.
Number of pages: 4
Pages: 449-452
Publication date: 17 Oct 2016

Host publication information

Title of host publication: AcademicMindtrek 2016 - Proceedings of the 20th International Academic Mindtrek Conference
Publisher: ACM
ISBN (Electronic): 978-1-4503-4367-1
ASJC Scopus subject areas: Human-Computer Interaction, Software, Computer Science Applications
Keywords: 3D interaction, Augmented reality, Mobile computing, Near-to-eye display, Virtual reality

Bibliographical note

EXT="Rakkolainen, Ismo"

Source: Scopus
Source ID: 84994852921

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

A movable immaterial volumetric display

We have created a movable, limitedly volumetric "immaterial" display. Our prototype is the first mobile, hand-held fogscreen. It can show e.g., slices of volumetric objects when swept across mid-air. It is based on the patented FogScreen [Fogio 2013] technology. The previous FogScreen installations have been fixed set-ups, where the screen device and a projector are typically rigged up, leaving space for the viewers to walk through the mid-air display. Also mid-air virtual reality and mid-air user interfaces have been implemented [DiVerdi et al. 2006, Rakkolainen et al. 2009]. 2013 Copyright held by the Owner/Author.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), University of Tampere
Contributors: Rakkolainen, I., Sand, A.
Publication date: 2013

Host publication information

Title of host publication: SIGGRAPH Asia 2013 Posters, SA 2013
Article number: 2
ISBN (Print): 9781450326346
ASJC Scopus subject areas: Computer Graphics and Computer-Aided Design, Software
Source: Scopus
Source ID: 84890958524

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Feature synthesis for image classification and retrieval via one-against-all perceptrons

Most existing content-based image retrieval and classification systems rely on low-level features which are automatically extracted from images. However, often these features lack the discrimination power needed for accurate description of the image content, and hence, they may lead to a poor retrieval or classification performance. We propose a novel technique to improve low-level features which uses parallel one-against-all perceptrons to synthesize new features with a higher discrimination power which in turn leads to improved classification and retrieval results. The proposed method can be applied on any database and low-level features as long as some ground-truth information is available. The main merits of the proposed technique are its simplicity and faster computation compared to existing feature synthesis methods. Extensive simulation results show a significant improvement in the features’ discrimination power.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Signal Processing, Research group: Video, Qatar University
Contributors: Raitoharju, J., Kiranyaz, S., Gabbouj, M.
Number of pages: 15
Pages: 943–957
Publication date: Feb 2018
Peer-reviewed: Yes
Early online date: 29 Jul 2016

Publication information

Journal: Neural Computing and Applications
Volume: 29
Issue number: 4
ISSN (Print): 0941-0643
Ratings: 
  • Scopus rating (2018): CiteScore 4.9 SJR 0.637 SNIP 1.521
Original language: English
ASJC Scopus subject areas: Artificial Intelligence, Software
Keywords: Content-based image retrieval and classification, Feature synthesis, Multi-dimensional particle swarm optimization, Multi-layer perceptrons

Bibliographical note

EXT="Kiranyaz, Serkan"

Source: Scopus
Source ID: 84979997953

Research output: Contribution to journalArticleScientificpeer-review

Gaussian mixture models for signal mapping and positioning

Maps of RSS from a wireless transmitter can be used for positioning or for planning wireless infrastructure. The RSS values measured at a single point are not always the same, but follow some distribution, which vary from point to point. In existing approaches in the literature this variation is neglected or its mapping requires making many measurements at every point, which makes the measurement collection very laborious. We propose to use GMs for modeling joint distributions of the position and the RSS value. The proposed model is more versatile than methods found in the literature as it models the joint distribution of RSS measurements and the location space. This allows us to model the distributions of RSS values in every point of space without making many measurement in every point. In addition, GMs allow us to compute conditional probabilities and posteriors of position in closed form. The proposed models can model any RSS attenuation pattern, which is useful for positioning in multifloor buildings. Our tests with WLAN signals show that positioning with the proposed algorithm provides accurate position estimates. We conclude that the proposed algorithm can provide useful information about distributions of RSS values for different applications.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences, Research group: Automation and Systems Theory, Aalto University, University of Liverpool, Universidad Antonio de Nebrija, Uppsala University
Contributors: Raitoharju, M., García-Fernández, F., Hostettler, R., Piché, R., Särkkä, S.
Publication date: 1 Mar 2020
Peer-reviewed: Yes
Early online date: 10 Oct 2019

Publication information

Journal: Signal Processing
Volume: 168
Article number: 107330
ISSN (Print): 0165-1684
Original language: English
ASJC Scopus subject areas: Control and Systems Engineering, Software, Signal Processing, Computer Vision and Pattern Recognition, Electrical and Electronic Engineering
Keywords: Gaussian mixtures, Indoor positioning, RSS, Signal mapping, Statistical modeling
URLs: 
Source: Scopus
Source ID: 85073693932

Research output: Contribution to journalArticleScientificpeer-review

Gaze-contingent scrolling and reading patterns

An automatic technique that scrolls the window content while the user is reading the text in the window has been implemented. Scrolling is triggered by gaze moving outside the reader's preferred reading zone. The reading patterns instigated by automatic scrolling are analyzed both quantitatively and using gaze path visualizations. Automatic scrolling is shown to result in smooth reading activity.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA)
Contributors: Räihä, K. J., Sharmin, S.
Number of pages: 4
Pages: 65-68
Publication date: 26 Oct 2014

Host publication information

Title of host publication: Proceedings of the NordiCHI 2014: The 8th Nordic Conference on Human-Computer Interaction: Fun, Fast, Foundational
Publisher: Association for Computing Machinery, Inc
ISBN (Electronic): 1595930361, 9781450325424
ASJC Scopus subject areas: Human-Computer Interaction, Software
Keywords: Analysis of reading, Gaze-based scrolling
Source: Scopus
Source ID: 84911385620

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

An exploratory study of eye typing fundamentals: Dwell time, text entry rate, errors, and workload

Although eye typing (typing on an on-screen keyboard via one's eyes as they are tracked by an eye tracker) has been studied for more than three decades now, we still know relatively little about it from the users' point of view. Standard metrics such as words per minute and keystrokes per character yield information only about the effectiveness of the technology and the interaction techniques developed for eye typing. We conducted an extensive study with almost five hours of eye typing per participant and report on extended qualitative and quantitative analysis of the relationship of dwell time, text entry rate, errors made, and workload experienced by the participants. The analysis method is comprehensive and stresses the need to consider different metrics in unison. The results highlight the importance of catering for individual differences and lead to suggestions for improvements in the interface.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA)
Contributors: Räihä, K. J., Ovaska, S.
Number of pages: 10
Pages: 3001-3010
Publication date: 2012

Host publication information

Title of host publication: Conference Proceedings - The 30th ACM Conference on Human Factors in Computing Systems, CHI 2012
ISBN (Print): 9781450310154
ASJC Scopus subject areas: Human-Computer Interaction, Computer Graphics and Computer-Aided Design, Software
Keywords: Adjustable dwell time, Error analysis, Extended study, Eye tracking, Eye typing, Workload
Source: Scopus
Source ID: 84862102858

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

On the costs of multiple trajectory pointing methods

Several enhanced pointing techniques aim to reduce the Fitts' law targeting distance by providing multiple target trajectories in the hope that a shorter path is available. However, these techniques introduce a search or decision component to pointing - users must examine the alternatives available and decide upon the trajectory to use. We analyse these difficulties, present a methodology for examining them as well as other behaviour issues, and report empirical results of performance with pointer wrapping and Ninja cursors. Results show that offering multiple trajectories incurs a significant search or decision cost, and that users are therefore poor at capitalising on the theoretical benefits of reduced target distance.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), University of Canterbury, Polytech' Paris-Sud
Contributors: Quinn, P., Cockburn, A., Räihä, K. J., Delamarche, J.
Number of pages: 4
Pages: 859-862
Publication date: 2011

Host publication information

Title of host publication: CHI 2011 - 29th Annual CHI Conference on Human Factors in Computing Systems, Conference Proceedings and Extended Abstracts
ISBN (Print): 9781450302289
ASJC Scopus subject areas: Human-Computer Interaction, Computer Graphics and Computer-Aided Design, Software
Keywords: Fitts' law, Multiple trajectories, Ninja cursors, Pointing, Search/decision, Wrapping cursors
Source: Scopus
Source ID: 79958170256

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Image database TID2013: Peculiarities, results and perspectives

This paper describes a recently created image database, TID2013, intended for evaluation of full-reference visual quality assessment metrics. With respect to TID2008, the new database contains a larger number (3000) of test images obtained from 25 reference images, 24 types of distortions for each reference image, and 5 levels for each type of distortion. Motivations for introducing 7 new types of distortions and one additional level of distortions are given; examples of distorted images are presented. Mean opinion scores (MOS) for the new database have been collected by performing 985 subjective experiments with volunteers (observers) from five countries (Finland, France, Italy, Ukraine, and USA). The availability of MOS allows the use of the designed database as a fundamental tool for assessing the effectiveness of visual quality. Furthermore, existing visual quality metrics have been tested with the proposed database and the collected results have been analyzed using rank order correlation coefficients between MOS and considered metrics. These correlation indices have been obtained both considering the full set of distorted images and specific image subsets, for highlighting advantages and drawbacks of existing, state of the art, quality metrics. Approaches to thorough performance analysis for a given metric are presented to detect practical situations or distortion types for which this metric is not adequate enough to human perception. The created image database and the collected MOS values are freely available for downloading and utilization for scientific purposes.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Signal Processing, Research group: Computational Imaging-CI, Research group: Algebraic and Algorithmic Methods in Signal Processing AAMSP, Signal Processing Research Community (SPRC), National Aerospace University, Dept of Transmitters, Receivers and Signal Processing, University of Rennes 1 - IETR, Media Communications Lab, USC Viterbi School of Engineering
Contributors: Ponomarenko, N., Jin, L., Ieremeiev, O., Lukin, V., Egiazarian, K., Astola, J., Vozel, B., Chehdi, K., Carli, M., Battisti, F., Jay Kuo, C. C.
Number of pages: 21
Pages: 57-77
Publication date: 1 Jan 2015
Peer-reviewed: Yes

Publication information

Journal: Signal Processing: Image Communication
Volume: 30
ISSN (Print): 0923-5965
Ratings: 
  • Scopus rating (2015): CiteScore 4 SJR 0.532 SNIP 1.413
Original language: English
ASJC Scopus subject areas: Computer Vision and Pattern Recognition, Signal Processing, Software, Electrical and Electronic Engineering
Keywords: Image denoising, Image lossy compression, Image visual quality metrics
Source: Scopus
Source ID: 84919839405

Research output: Contribution to journalArticleScientificpeer-review

Methods and tools for denoising of complex-valued images based on block-matching and high order singular value decomposition

Noise suppression in complex-valued data is an important task for a wide class of applications, in particular concerning the phase retrieval in coherent imaging. The approaches based on BM3D techniques are ones of the most successful in the field. In this paper, we propose and develop a new class of BM3Dstyle algorithms, which use high order (3D and 4D) singular value decomposition (HOSVD) for transform design in complex domain. This set of the novel algorithms is implemented as a toolbox In Matlab. This development is produced for various types of the complex-domain sparsity: directly in complex domain, real/imaginary and phase/ amplitude parts of complexvalued variables. The group-wise transform design is combined with the different kinds of thresholding including multivariable Wiener filtering. The toolbox includes iterative and non-iterative novel complex-domain algorithms (filters). The efficiency of the developed algorithms is demonstrated on denoising problems with an additive Gaussian complex-valued noise. A special set of the complex-valued test-images was developed with spatially varying correlated phase and amplitudes imitating data typical for optical interferometry and holography. It is shown that for this class of the test-images the developed algorithms demonstrate the stateof- the-art performance.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing
Contributors: Ponomarenko, M., Katkovnik, V., Egiazarian, K.
Publication date: 2018

Host publication information

Title of host publication: Electronic Imaging : Image Processing: Algorithms and Systems XVI
Publisher: Society for Imaging Science and Technology
ASJC Scopus subject areas: Computer Graphics and Computer-Aided Design, Computer Science Applications, Human-Computer Interaction, Software, Electrical and Electronic Engineering, Atomic and Molecular Physics, and Optics
Keywords: Block matching, Complex domain, Higher-order singular value decomposition, Image denoising, Phase imaging, Sparsity

Bibliographical note

jufoid=84313

Source: Scopus
Source ID: 85052877244

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Blind estimation of white Gaussian noise variance in highly textured images

In the paper, a new method of blind estimation of noise variance in a single highly textured image is proposed. An input image is divided into 8x8 blocks and discrete cosine transform (DCT) is performed for each block. A part of 64 DCT coefficients with lowest energy calculated through all blocks is selected for further analysis. For the DCT coefficients, a robust estimate of noise variance is calculated. Corresponding to the obtained estimate, a part of blocks having very large values of local variance calculated only for the selected DCT coefficients are excluded from the further analysis. These two steps (estimation of noise variance and exclusion of blocks) are iteratively repeated three times. For the verification of the proposed method, a new noise-free test image database TAMPERE17 consisting of many highly textured images is designed. It is shown for this database and different values of noise variance from the set {25, 49, 100, 225}, that the proposed method provides approximately two times lower estimation root mean square error than other methods.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing, Don State Technical University
Contributors: Ponomarenko, M., Gapon, N., Voronin, V., Egiazarian, K.
Publication date: 2018

Host publication information

Title of host publication: Electronic Imaging : Image Processing: Algorithms and Systems XVI
Publisher: Society for Imaging Science and Technology
ASJC Scopus subject areas: Computer Graphics and Computer-Aided Design, Computer Science Applications, Human-Computer Interaction, Software, Electrical and Electronic Engineering, Atomic and Molecular Physics, and Optics
Keywords: Blind estimation of noise characteristics, Discrete cosine transform (DCT), Noise free test image database

Bibliographical note

jufoid=84313

Source: Scopus
Source ID: 85052856410

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Additional lossless compression of JPEG images based on BPG

The task of additional lossless compression of JPEG images is considered. We propose to decode JPEG image and recompress it using lossy BPG (Better Portable Graphics) codec based on a subset of the HEVC open video compression standard. Then the decompressed and smoothed BPG image is used for calculation and quantization of DCT coefficients in 8x8 image blocks using quantization tables of the source JPEG image. A difference between obtained quantized DCT coefficients and quantized DCT coefficients of the source JPEG image (prediction error) is calculated. The difference is lossless compressed by a proposed context modeling and arithmetical coding. In this way the source JPEG image is replaced by two files: compressed BPG image and the compressed difference which needed for lossless restoration of the source JPEG image. It is shown that the proposed approach provides compression ratios comparable with state of the art PAQ8, WinZip and STUFFIT file archivers. At the same time BPG images may be used for fast preview of compressed JPEG images.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Kharkiv National Aerospace University
Contributors: Ponomarenko, M., Miroshnichenko, O., Lukin, V., Egiazarian, K.
Publication date: 13 Jan 2019

Host publication information

Title of host publication: Image Processing: Algorithms and Systems XVII

Publication series

Name: IS and T International Symposium on Electronic Imaging Science and Technology
ASJC Scopus subject areas: Computer Graphics and Computer-Aided Design, Computer Science Applications, Human-Computer Interaction, Software, Electrical and Electronic Engineering, Atomic and Molecular Physics, and Optics
Keywords: Context modelling, Discrete cosine transform, JPEG, JPEG additional compression
Source: Scopus
Source ID: 85080092000

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Phase masks optimization for broadband diffractive imaging

The task of optimization of phase masks for broadband diffractive imaging to minimize chromatic aberrations and to provide given value of Depth of Focus (DoF) is considered. Different schemes of multilevel phase mask (MPM) forming by combining pixels of two Fresnel lenses are analyzed. The Fresnel lenses are calculated for the same focal distance but for very different wavelengths. A possibility of adding to the optimized mask a cubic component is taking into account as well as usage of discrete phase masks with optimized number of levels. It is shown that the proposed approach in the combination with inverse imaging allows to significantly increase image quality for a focus distance in comparison to refractive lens-based optical systems. Moreover, it is shown that by changing of aforementioned parameters it is possible to increase or decrease DoF value depending from a given goal of optimization. It is demonstrated by numerical analysis that the proposed approach significantly increases robustness of designed MPM to Gaussian additive noise in MPM introduced due to fabrication errors.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Research group: Computational Imaging-CI
Contributors: Ponomarenko, M., Katkovnik, V., Egiazarian, K.
Publication date: 13 Jan 2019

Host publication information

Title of host publication: Image Processing: Algorithms and Systems XVII

Publication series

Name: IS and T International Symposium on Electronic Imaging Science and Technology
ASJC Scopus subject areas: Computer Graphics and Computer-Aided Design, Computer Science Applications, Human-Computer Interaction, Software, Electrical and Electronic Engineering, Atomic and Molecular Physics, and Optics
Keywords: Diffractive optical elements, Inverse imaging, Lensless imaging, Multilevel phase mask design
Source: Scopus
Source ID: 85080039777

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Human-technology choreographies: Re-thinking body, movement and space in interaction design

Bodily movements have traditionally had mostly instrumental value in interaction design. However, movements can also be given a central role in understanding behaviour and in designing technology for humans. This workshop is aiming at taking a fresh, movement-oriented look at the design and evaluation of technology in a wide variety of contexts. Copyright is held by the owner/author(s).

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), Jyväskylän yliopisto, School of Management (JKK)
Contributors: Pirhonen, A., Parviainen, J., Tuuri, K., Turunen, M., Heimonen, T.
Number of pages: 4
Pages: 841-844
Publication date: 26 Oct 2014

Host publication information

Title of host publication: Proceedings of the NordiCHI 2014: The 8th Nordic Conference on Human-Computer Interaction: Fun, Fast, Foundational
Publisher: Association for Computing Machinery, Inc
ISBN (Electronic): 1595930361, 9781450325424
ASJC Scopus subject areas: Human-Computer Interaction, Software
Keywords: Choreography, Embodiment, Interaction design, Lived space
Source: Scopus
Source ID: 84911381050

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

A lightweight many-to-many authentication protocol for near field communications

In this paper the lightweight many-to-many authentication protocol, that uses Near Field Communications as a carrier technology is proposed. The solution works without any user interaction and can be applied for almost any data storage device: NFC or RFID tag, USB-flash drive, etc. The major novelty of the system is real-time encryption key generation algorithm. This approach doesn't require any computation power on the tag, trusted third parties or secure link between tag and information system. So far, the mentioned features transforms to significant advantages of the proposed solution, while compared to existing analogues: OAuth, Opacity and LMAP. At the same time, the integrity of key sequences is not guarantied, that brings motivation for future research in the field.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research group: Emerging Technologies for Nano-Bio-Info-Cogno, Department of Electronics and Communications Engineering, Wireless Communications and Positioning (WICO), Nano Communication Centre, Yaroslavl State University
Contributors: Petrov, V., Komar, M., Koucheryavy, Y.
Publication date: 2013

Host publication information

Title of host publication: Proceedings of the 2013 21st IEEE International Conference on Network Protocols, ICNP 2013
Publisher: IEEE COMPUTER SOCIETY PRESS
Article number: 6733633
ISBN (Print): 9781479912704
ASJC Scopus subject areas: Computer Networks and Communications, Software
Source: Scopus
Source ID: 84896795715

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Distant speech separation using predicted time-frequency masks from spatial features

Speech separation algorithms are faced with a difficult task of producing high degree of separation without containing unwanted artifacts. The time-frequency (T-F) masking technique applies a real-valued (or binary) mask on top of the signal's spectrum to filter out unwanted components. The practical difficulty lies in the mask estimation. Often, using efficient masks engineered for separation performance leads to presence of unwanted musical noise artifacts in the separated signal. This lowers the perceptual quality and intelligibility of the output. Microphone arrays have been long studied for processing of distant speech. This work uses a feed-forward neural network for mapping microphone array's spatial features into a T-F mask. Wiener filter is used as a desired mask for training the neural network using speech examples in simulated setting. The T-F masks predicted by the neural network are combined to obtain an enhanced separation mask that exploits the information regarding interference between all sources. The final mask is applied to the delay-and-sum beamformer (DSB) output. The algorithm's objective separation capability in conjunction with the separated speech intelligibility is tested with recorded speech from distant talkers in two rooms from two distances. The results show improvement in instrumental measure for intelligibility and frequency-weighted SNR over complex-valued non-negative matrix factorization (CNMF) source separation approach, spatial sound source separation, and conventional beamforming methods such as the DSB and minimum variance distortionless response (MVDR).

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Signal Processing, Research group: Audio research group
Contributors: Pertilä, P., Nikunen, J.
Number of pages: 10
Pages: 97-106
Publication date: 2015
Peer-reviewed: Yes

Publication information

Journal: Speech Communication
Volume: 68
ISSN (Print): 0167-6393
Ratings: 
  • Scopus rating (2015): CiteScore 4.1 SJR 0.49 SNIP 1.612
Original language: English
ASJC Scopus subject areas: Modelling and Simulation, Computer Science Applications, Computer Vision and Pattern Recognition, Software, Communication, Linguistics and Language, Language and Linguistics
Keywords: Beamforming, Microphone arrays, Neural networks, Speech separation, Time-frequency masking
Source: Scopus
Source ID: 84923277715

Research output: Contribution to journalArticleScientificpeer-review

Time Difference of Arrival Estimation of Speech Signals Using Deep Neural Networks with Integrated Time-frequency Masking

The Time Difference of Arrival (TDoA) of a sound wavefront impinging on a microphone pair carries spatial information about the source. However, captured speech typically contains dynamic non-speech interference sources and noise. Therefore, the TDoA estimates fluctuate between speech and interference. Deep Neural Networks (DNNs) have been applied for Time-Frequency (TF) masking for Acoustic Source Localization (ASL) to filter out non-speech components from a speaker location likelihood function. However, the type of TF mask for this task is not obvious. Secondly, the DNN should estimate the TDoA values, but existing solutions estimate the TF mask instead. To overcome these issues, a direct formulation of the TF masking as a part of a DNN-based ASL structure is proposed. Furthermore, the proposed network operates in an online manner, i.e., producing estimates frame-by-frame. Combined with the use of recurrent layers it exploits the sequential progression of speaker related TDoAs. Training with different microphone spacings allows model re-use for different microphone pair geometries in inference. Real-data experiments with smartphone recordings of speech in interference demonstrate the network's generalization capability.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences
Contributors: Pertilä, P., Parviainen, M.
Number of pages: 5
Pages: 436-440
Publication date: 1 May 2019

Host publication information

Title of host publication: 2019 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2019 - Proceedings
Publisher: IEEE
ISBN (Electronic): 9781479981311
ASJC Scopus subject areas: Software, Signal Processing, Electrical and Electronic Engineering
Keywords: Acoustic Source Localization, Microphone Arrays, Recurrent Neural Networks, Time-Frequency Masking
Electronic versions: 
Source: Scopus
Source ID: 85068957469

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Information retrieval approach to meta-visualization

Visualization is crucial in the first steps of data analysis. In visual data exploration with scatter plots, no single plot is sufficient to analyze complicated high-dimensional data sets. Given numerous visualizations created with different features or methods, meta-visualization is needed to analyze the visualizations together. We solve how to arrange numerous visualizations onto a meta-visualization display, so that their similarities and differences can be analyzed. Visualization has recently been formalized as an information retrieval task; we extend this approach, and formalize meta-visualization as an information retrieval task whose performance can be rigorously quantified and optimized. We introduce a machine learning approach to optimize the meta-visualization, based on an information retrieval perspective: two visualizations are similar if the analyst would retrieve similar neighborhoods between data samples from either visualization. Based on the approach, we introduce a nonlinear embedding method for meta-visualization: it optimizes locations of visualizations on a display, so that visualizations giving similar information about data are close to each other. In experiments we show such meta-visualization outperforms alternatives, and yields insight into data in several case studies.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Research Community on Data-to-Decision (D2D), Aalto University
Contributors: Peltonen, J., Lin, Z.
Number of pages: 41
Pages: 189-229
Publication date: 1 May 2015
Peer-reviewed: Yes

Publication information

Journal: Machine Learning
Volume: 99
Issue number: 2
ISSN (Print): 0885-6125
Ratings: 
  • Scopus rating (2015): CiteScore 5.2 SJR 1.257 SNIP 2.054
Original language: English
ASJC Scopus subject areas: Software, Artificial Intelligence
Keywords: Meta-visualization, Neighbor embedding, Nonlinear dimensionality reduction
Source: Scopus
Source ID: 84939887799

Research output: Contribution to journalArticleScientificpeer-review

Information retrieval perspective to meta-visualization

In visual data exploration with scatter plots, no single plot is sufficient to analyze complicated high-dimensional data sets. Given numerous visualizations created with different features or methods, meta-visualization is needed to analyze the visualizations together. We solve how to arrange numerous visualizations onto a meta-visualization display, so that their similarities and differences can be analyzed. We introduce a machine learning approach to optimize the meta-visualization, based on an information retrieval perspective: Two visualizations are similar if the analyst would retrieve similar neighborhoods between data samples from either visualization. Based on the approach, we introduce a nonlinear embedding method for meta-visualization: it optimizes locations of visualizations on a display, so that visualizations giving similar information about data are close to each other.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Research Community on Data-to-Decision (D2D), Aalto University
Contributors: Peltonen, J., Lin, Z.
Number of pages: 16
Pages: 165-180
Publication date: 2013
Peer-reviewed: Yes

Publication information

Journal: Journal of Machine Learning Research
Volume: 29
ISSN (Print): 1532-4435
Ratings: 
  • Scopus rating (2013): CiteScore 6.2 SJR 1.235 SNIP 2.293
Original language: English
ASJC Scopus subject areas: Artificial Intelligence, Software, Control and Systems Engineering, Statistics and Probability
Keywords: Meta-visualization, Neighbor embedding, Nonlinear dimensionality reduction
Source: Scopus
Source ID: 84908485499

Research output: Contribution to journalArticleScientificpeer-review

Generative modeling for maximizing precision and recall in information visualization

Information visualization has recently been formulated as an information retrieval problem, where the goal is to find similar data points based on the visualized nonlinear projection, and the visualization is optimized to maximize a compromise between (smoothed) precision and recall. We turn the visualization into a generative modeling task where a simple user model parameterized by the data coordinates is optimized, neighborhood relations are the observed data, and straightforward maximum likelihood estimation corresponds to Stochastic Neighbor Embedding (SNE). While SNE maximizes pure recall, adding a mixture component that "explains away" misses allows our generative model to focus on maximizing precision as well. The resulting model is a generative solution to maximizing tradeoffs between precision and recall. The model outperforms earlier models in terms of precision and recall and in external validation by unsupervised classification.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Research Community on Data-to-Decision (D2D), Aalto University, University of Helsinki
Contributors: Peltonen, J., Kaski, S.
Number of pages: 9
Pages: 579-587
Publication date: 2011
Peer-reviewed: Yes

Publication information

Journal: Journal of Machine Learning Research
Volume: 15
ISSN (Print): 1532-4435
Ratings: 
  • Scopus rating (2011): CiteScore 7.7 SJR 1.18 SNIP 2.912
Original language: English
ASJC Scopus subject areas: Artificial Intelligence, Software, Control and Systems Engineering, Statistics and Probability
Source: Scopus
Source ID: 84862299625

Research output: Contribution to journalArticleScientificpeer-review

Reproducible Evaluation of System Efficiency with a Model of Architecture: From Theory to Practice

Current trends in high performance and embedded computing include design of increasingly complex hardware architectures with high parallelism, heterogeneous processing elements and non-uniform communication resources. In order to take hardware and software design decisions, early evaluations of the system non-functional properties are needed. These evaluations of system efficiency require Electronic System-Level (ESL) information on both the algorithms and the architecture. Contrary to algorithm models for which a major body of work has been conducted on defining formal Models of Computation (MoCs), architecture models from the literature are mostly empirical models from which reproducible experimentation requires the accompanying software. In this paper, a precise definition of a Model of Architecture (MoA) is proposed that focuses on reproducibility and abstraction and removes the overlap previously existing between the notions of MoA and MoC. A first MoA, called the Linear System-Level Architecture Model (LSLA), is presented. To demonstrate the generic nature of the proposed new architecture modeling concepts, we show that the LSLA Model can be integrated flexibly with different MoCs. LSLA is then used to model the energy consumption of a State-of-the-Art Multiprocessor System-on-Chip (MPSoC) when running an application described using the Synchronous Dataflow (SDF) MoC. A method to automatically learn LSLA model parameters from platform measurements is introduced. Despite the high complexity of the underlying hardware and software, a simple LSLA model is demonstrated to estimate the energy consumption of the MPSoC with a fidelity of 86%.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Pervasive Computing, UBL, Scuola Superiore sant'Anna, University of Maryland
Contributors: Pelcat, M., Mercat, A., Desnos, K., Maggiani, L., Liu, Y., Heulot, J., Nezan, J. F., Hamidouche, W., Menard, D., Bhattacharyya, S. S.
Pages: 2050-2063
Publication date: Oct 2018
Peer-reviewed: Yes
Early online date: 16 Nov 2017

Publication information

Journal: IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
Volume: 37
Issue number: 10
ISSN (Print): 0278-0070
Ratings: 
  • Scopus rating (2018): CiteScore 4.6 SJR 0.476 SNIP 1.737
Original language: English
ASJC Scopus subject areas: Software, Computer Graphics and Computer-Aided Design, Electrical and Electronic Engineering
Keywords: Algorithm design and analysis, architecture, Complexity theory, Computational modeling, Computer architecture, design space exploration, Energy consumption, Hardware, hardware/software co-design, modeling, multiprocessor SoC, performance optimization, Ports (Computers), power modeling and estimation., system on chip
Source: Scopus
Source ID: 85035150836

Research output: Contribution to journalArticleScientificpeer-review

Deep Temporal Logistic Bag-of-features for Forecasting High Frequency Limit Order Book Time Series

Forecasting time series has several applications in various domains. The vast amount of data that are available nowadays provide the opportunity to use powerful deep learning approaches, but at the same time pose significant challenges of high-dimensionality, velocity and variety. In this paper, a novel logistic formulation of the well-known Bag-of-Features model is proposed to tackle these challenges. The proposed method is combined with deep convolutional feature extractors and is capable of accurately modeling the temporal behavior of time series, forming powerful forecasting models that can be trained in an end-to-end fashion. The proposed method was extensively evaluated using a large-scale financial time series dataset, that consists of more than 4 million limit orders, outperforming other competitive methods.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, School of Informatics, Aristotle University of Thessaloniki, Aarhus Universitet
Contributors: Passalis, N., Tefas, A., Kanniainen, J., Gabbouj, M., Iosifidis, A.
Number of pages: 5
Pages: 7545-7549
Publication date: 1 May 2019

Host publication information

Title of host publication: 2019 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2019 - Proceedings
Publisher: IEEE
ISBN (Electronic): 9781479981311
ASJC Scopus subject areas: Software, Signal Processing, Electrical and Electronic Engineering
Keywords: Limit Order Book, Temporal Bag-of-Features, Time series forecasting

Bibliographical note

EXT="Tefas, Anastasios"
EXT="Iosifidis, Alexandros"

Source: Scopus
Source ID: 85069000578

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Variance Preserving Initialization for Training Deep Neuromorphic Photonic Networks with Sinusoidal Activations

Photonic neuromorphic hardware can provide significant performance benefits for Deep Learning (DL) applications by accelerating and reducing the energy requirements of DL models. However, photonic neuromorphic architectures employ different activation elements than those traditionally used in DL, slowing down the convergence of the training process for such architectures. An initialization scheme that can be used to efficiently train deep photonic networks that employ quadratic sinusoidal activation functions is proposed in this paper. The proposed initialization scheme can overcome these limitations, leading to faster and more stable training of deep photonic neural networks. The ability of the proposed method to improve the convergence of the training process is experimentally demonstrated using two different DL architectures and two datasets.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Aristotle University of Thessaloniki
Contributors: Passalis, N., Mourgias-Alexandris, G., Tsakyridis, A., Pleros, N., Tefas, A.
Number of pages: 5
Pages: 1483-1487
Publication date: 1 May 2019

Host publication information

Title of host publication: 2019 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2019 - Proceedings
Publisher: IEEE
ISBN (Electronic): 9781479981311
ASJC Scopus subject areas: Software, Signal Processing, Electrical and Electronic Engineering
Keywords: Neuromorphic Hardware, Photonic Neural Networks, Sinusoidal Activations

Bibliographical note

EXT="Tefas, Anastasios"

Source: Scopus
Source ID: 85064389224

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Adaptive Normalization for Forecasting Limit Order Book Data Using Convolutional Neural Networks

Deep learning models are capable of achieving state-of-the-art performance on a wide range of time series analysis tasks. However, their performance crucially depends on the employed normalization scheme, while they are usually unable to efficiently handle non-stationary features without first appropriately pre-processing them. These limitations impact the performance of deep learning models, especially when used for forecasting financial time series, due to their non-stationary and multimodal nature. In this paper we propose a data-driven adaptive normalization layer which is capable of learning the most appropriate normalization scheme that should be applied on the data. To this end, the proposed method first identifies the distribution from which the data were generated and then it dynamically shifts and scales them in order to facilitate the task at hand. The proposed nor-malization scheme is fully differentiable and it is trained in an end-to-end fashion along with the rest of the parameters of the model. The proposed method leads to significant performance improvements over several competitive normalization approaches, as demonstrated using a large-scale limit order book dataset.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Research group: Multimedia Research Group - MRG, Aristotle University of Thessaloniki, Aarhus Universitet
Contributors: Passalis, N., Tefas, A., Kanniainen, J., Gabbouj, M., Iosifidis, A.
Number of pages: 5
Pages: 1713-1717
Publication date: 1 May 2020

Host publication information

Title of host publication: 2020 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2020 - Proceedings
Publisher: IEEE
ISBN (Electronic): 9781509066315

Publication series

Name: ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings
Volume: 2020-May
ISSN (Print): 1520-6149
ASJC Scopus subject areas: Software, Signal Processing, Electrical and Electronic Engineering

Bibliographical note

EXT="Tefas, Anastasios"
EXT="Iosifidis, Alexandros"

Source: Scopus
Source ID: 85089240342

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Exploring the role of ten universal values in using products and services

The aim of this research was to explore the role of Schwartz's ten universal human values in the context of using products and services. Seventy-five participants were asked to qualitatively describe a product or service especially well in line with their values and a product or service in conflict with their values, and to evaluate them on a number of rating scales. The scales included 30 statements (three statements per universal value) probing the presence of each value in user experiences related to products and services and 10 statements studying the perceived importance of each value. The results showed that all the ten universal values were relevant in the evaluations of products and services both in line with the users' values and in conflict with the users' values. In the current sample, hedonism and self-direction were rated as the values most frequently present and most important in the evaluations of products and services in line with values. Power was rated as a moderately important value for products in conflict with values, but significantly less important for products in line with values. Achievement values were frequently reported in the qualitative descriptions, but they were less prominent in the quantitative data. The results suggest that the model of ten universal values is promising in understanding the role of users' value preferences in using products and services, and it seems to have potential for complementing the psychological needs approach in understanding user experience.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Pervasive Computing, Department of Computer Science, Aalto University
Contributors: Partala, T., Kujala, S.
Number of pages: 21
Pages: 311-331
Publication date: 1 May 2016
Peer-reviewed: Yes

Publication information

Journal: Interacting with Computers
Volume: 28
Issue number: 3
ISSN (Print): 0953-5438
Ratings: 
  • Scopus rating (2016): CiteScore 3.5 SJR 0.374 SNIP 1.128
Original language: English
ASJC Scopus subject areas: Human-Computer Interaction, Software
Keywords: empirical studies in HCI, HCI design and evaluation methods, user experience, user values, value-sensitive design
Source: Scopus
Source ID: 84966359109

Research output: Contribution to journalArticleScientificpeer-review

Towards secure cloud orchestration for multi-cloud deployments

Cloud orchestration frameworks are commonly used to deploy and operate cloud infrastructure. Their role spans both vertically (deployment on infrastructure, platform, application and microservice levels) and horizontally (deployments from many distinct cloud resource providers). However, despite the central role of orchestration, the popular orchestration frameworks lack mechanisms to provide security guarantees for cloud operators. In this work, we analyze the security landscape of cloud orchestration frameworks for multi-cloud infrastructure. We identify a set of attack scenarios, define security enforcement enablers and propose an architecture for a security-enabled cloud orchestration framework for multi-cloud application deployments.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, RISE SICS, University of Westminster
Contributors: Paladi, N., Michalas, A., Dang, H. V.
Publication date: 23 Apr 2018

Host publication information

Title of host publication: CrossCloud 2018 - 5th Workshop on CrossCloud Infrastructures and Platforms, colocated with EuroSys 2018
Publisher: ACM
Article number: a4
ISBN (Electronic): 9781450356534
ASJC Scopus subject areas: Information Systems, Software, Computer Science Applications
Keywords: Cloud infrastructure, Microser-vices, Orchestration, Security, Virtualization
Source: Scopus
Source ID: 85049685222

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Domain based storage protection with secure access control for the cloud

Cloud computing has evolved from a promising concept to one of the fastest growing segments of the IT industry. However, many businesses and individuals continue to view cloud computing as a technology that risks exposing their data to unauthorized users. We introduce a data confidentiality and integrity protection mechanism for Infrastructure-as-a-Service (IaaS) clouds, which relies on trusted computing principles to provide transparent storage isolation between IaaS clients. We also address the absence of reliable data sharing mechanisms, by providing an XML-based language framework which enables clients of IaaS clouds to securely share data and clearly define access rights granted to peers. The proposed improvements have been prototyped as a code extension for a popular cloud platform.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: SICS
Contributors: Paladi, N., Michalas, A., Gehrmann, C.
Number of pages: 8
Pages: 35-42
Publication date: 1 Jan 2014

Host publication information

Title of host publication: SCC 2014 - Proceedings of the 2nd International Workshop on Security in Cloud Computing
Publisher: Association for Computing Machinery
ISBN (Print): 9781450328050
ASJC Scopus subject areas: Software
Keywords: cloud computing, IaaS, security, storage protection
Source: Scopus
Source ID: 84902766965

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Optimizing spatial and temporal reuse in wireless networks by decentralized partially observable markov decision processes

The performance of medium access control (MAC) depends on both spatial locations and traffic patterns of wireless agents. In contrast to conventional MAC policies, we propose a MAC solution that adapts to the prevailing spatial and temporal opportunities. The proposed solution is based on a decentralized partially observable Markov decision process (DEC-POMDP), which is able to handle wireless network dynamics described by a Markov model. A DEC-POMDP takes both sensor noise and partial observations into account, and yields MAC policies that are optimal for the network dynamics model. The DEC-POMDP MAC policies can be optimized for a freely chosen goal, such as maximal throughput or minimal latency, with the same algorithm. We make approximate optimization efficient by exploiting problem structure: the policies are optimized by a factored DEC-POMDP method, yielding highly compact state machine representations for MAC policies. Experiments show that our approach yields higher throughput and lower latency than CSMA/CA based comparison methods adapted to the current wireless network configuration.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Research Community on Data-to-Decision (D2D), Aalto University, Asparrow Ltd, Helsinki Institute for Information Technology
Contributors: Pajarinen, J., Hottinen, A., Peltonen, J.
Number of pages: 14
Pages: 866-879
Publication date: Apr 2014
Peer-reviewed: Yes

Publication information

Journal: IEEE Transactions on Mobile Computing
Volume: 13
Issue number: 4
Article number: 6482133
ISSN (Print): 1536-1233
Ratings: 
  • Scopus rating (2014): CiteScore 7.5 SJR 1.192 SNIP 3.51
Original language: English
ASJC Scopus subject areas: Software, Computer Networks and Communications, Electrical and Electronic Engineering
Keywords: decentralized POMDP, medium access control, multi-agent planning, Spatial reuse, wireless network
Source: Scopus
Source ID: 84897873909

Research output: Contribution to journalArticleScientificpeer-review

Compatible natural gradient policy search

Trust-region methods have yielded state-of-the-art results in policy search. A common approach is to use KL-divergence to bound the region of trust resulting in a natural gradient policy update. We show that the natural gradient and trust region optimization are equivalent if we use the natural parameterization of a standard exponential policy distribution in combination with compatible value function approximation. Moreover, we show that standard natural gradient updates may reduce the entropy of the policy according to a wrong schedule leading to premature convergence. To control entropy reduction we introduce a new policy search method called compatible policy search (COPOS) which bounds entropy loss. The experimental results show that COPOS yields state-of-the-art results in challenging continuous control tasks and in discrete partially observable tasks.

General information

Publication status: E-pub ahead of print
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences, Intelligent Autonomous Systems, Technical University Darmstadt, MPI for Intelligent Systems, University of Lincoln
Contributors: Pajarinen, J., Thai, H. L., Akrour, R., Peters, J., Neumann, G.
Publication date: 2019
Peer-reviewed: Yes

Publication information

Journal: Machine Learning
ISSN (Print): 0885-6125
Ratings: 
  • Scopus rating (2019): CiteScore 5 SJR 1.034 SNIP 1.941
Original language: English
ASJC Scopus subject areas: Software, Artificial Intelligence
Keywords: Policy search, Reinforcement learning
Electronic versions: 
Source: Scopus
Source ID: 85066145275

Research output: Contribution to journalArticleScientificpeer-review

Seniors and text messaging on mobile touchscreen phones

We studied how senior citizens write and send text messages on their own mobile phone and two touchscreen smartphones. Each participant participated in three training sessions and wrote messages with three phones. We found that the range of text entry performance among seniors is large. Average text entry rate in entering a 34 character test phrase was only 3.5 wpm. Further work to improve text messaging user interfaces for older un-skilled users is clearly needed. Copyright is held by the owner/author(s).

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), Korea Advanced Institute of Science and Technology (KAIST)
Contributors: Övermark, R., Isokoski, P., Ovaska, S.
Number of pages: 4
Pages: 967-970
Publication date: 26 Oct 2014

Host publication information

Title of host publication: Proceedings of the NordiCHI 2014: The 8th Nordic Conference on Human-Computer Interaction: Fun, Fast, Foundational
Publisher: Association for Computing Machinery, Inc
ISBN (Electronic): 1595930361, 9781450325424
ASJC Scopus subject areas: Human-Computer Interaction, Software
Keywords: Learning, Mobile phone, Older adult, Text messaging, Touchscreen
Source: Scopus
Source ID: 84911409889

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Continuum approach to high-cycle fatigue. The finite life-time case with stochastic stress history

In this paper, we consider continuum approach for high-cycle fatigue in the case where life-time is finite. The method is based on differential equations and all basic concepts are explained. A stress history is assumed to be a stochastic process and this leads us to the theory of stochastic differential equations. The life-time is a quantity, which tells us when the breakdown of the material happens. In this method, it is naturally a random variable. The basic assumption is, that the distribution of the life-time is log-normal or Weibull. We give a numerical basic example to demonstrate the method.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Computing Sciences
Contributors: Orelma, H.
Number of pages: 12
Pages: 452-463
Publication date: 2019
Peer-reviewed: Yes

Publication information

Journal: Vestnik Samarskogo Gosudarstvennogo Tekhnicheskogo Universiteta, Seriya Fiziko-Matematicheskie Nauki
Volume: 23
Issue number: 3
ISSN (Print): 1991-8615
Ratings: 
  • Scopus rating (2019): CiteScore 0
Original language: English
ASJC Scopus subject areas: Mechanics of Materials, Condensed Matter Physics, Mathematical Physics, Modelling and Simulation, Analysis, Applied Mathematics, Software
Keywords: Evolution equation, High-cycle fatigue, Life-time
Source: Scopus
Source ID: 85079143163

Research output: Contribution to journalArticleScientificpeer-review

Challenges of Multi-Factor Authentication for Securing Advanced IoT Applications

The unprecedented proliferation of smart devices together with novel communication, computing, and control technologies have paved the way for A-IoT. This development involves new categories of capable devices, such as high-end wearables, smart vehicles, and consumer drones aiming to enable efficient and collaborative utilization within the smart city paradigm. While massive deployments of these objects may enrich people's lives, unauthorized access to said equipment is potentially dangerous. Hence, highly secure human authentication mechanisms have to be designed. At the same time, human beings desire comfortable interaction with the devices they own on a daily basis, thus demanding authentication procedures to be seamless and user-friendly, mindful of contemporary urban dynamics. In response to these unique challenges, this work advocates for the adoption of multi-factor authentication for A-IoT, such that multiple heterogeneous methods - both well established and emerging - are combined intelligently to grant or deny access reliably. We thus discuss the pros and cons of various solutions as well as introduce tools to combine the authentication factors, with an emphasis on challenging smart city environments. We finally outline the open questions to shape future research efforts in this emerging field.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Electrical Engineering, National Research University Higher School of Economics, ITMO University, Electrical Engineering Department, University of California, Los Angeles (UCLA)
Contributors: Ometov, A., Petrov, V., Bezzateev, S., Andreev, S., Koucheryavy, Y., Gerla, M.
Number of pages: 7
Pages: 82-88
Publication date: 1 Mar 2019
Peer-reviewed: Yes

Publication information

Journal: IEEE Network
Volume: 33
Issue number: 2
ISSN (Print): 0890-8044
Ratings: 
  • Scopus rating (2019): CiteScore 21.6 SJR 2.773 SNIP 3.323
Original language: English
ASJC Scopus subject areas: Software, Information Systems, Hardware and Architecture, Computer Networks and Communications
Source: Scopus
Source ID: 85063775257

Research output: Contribution to journalArticleScientificpeer-review

Layers of user expectations of future technologies: An early framework

User's expectations are identified as a factor affecting the actual user experience in human-computer interaction. Considering the context of emerging and future technologies, users' expectations can become increasingly diverse, especially in terms of where they stem from. This paper presents an early framework for understanding different layers of expectations that people might have of technologies in the near future: for example, 'desires' and 'social and societal norms'. The framework provides understanding of the spectrum of user expectations and what different aspects of them could be identified in user inquiries and evaluations. For concretization and credibility of this work-in-progress framework, examples from recent research on user expectations of mobile augmented reality are provided.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Augmented Human Activities (AHA)
Contributors: Olsson, T.
Number of pages: 6
Pages: 1957-1962
Publication date: 2014

Host publication information

Title of host publication: CHI EA 2014: One of a ChiNd - Extended Abstracts, 32nd Annual ACM Conference on Human Factors in Computing Systems
Publisher: Association for Computing Machinery
ISBN (Print): 9781450324748
ASJC Scopus subject areas: Human-Computer Interaction, Computer Graphics and Computer-Aided Design, Software
Keywords: Anticipation, Emerging technologies, Expectation, Framework, Quality, User experience, User studies
Source: Scopus
Source ID: 84900561033

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

System integration for real-time mobile manipulation

Mobile manipulators are one of the most complicated types of mechatronics systems. The performance of these robots in performing complex manipulation tasks is highly correlated with the synchronization and integration of their low-level components. This paper discusses in detail the mechatronics design of a four wheel steered mobile manipulator. It presents the manipulator's mechanical structure and electrical interfaces, designs low-level software architecture based on embedded PC-based controls, and proposes a systematic solution based on code generation products of MATLAB and Simulink. The remote development environment described here is used to develop real-time controller software and modules for the mobile manipulator under a POSIX-compliant, real-time Linux operating system. Our approach enables developers to reliably design controller modules that meet the hard real-time constraints of the entire low-level system architecture. Moreover, it provides a systematic framework for the development and integration of hardware devices with various communication mediums and protocols, which facilitates the development and integration process of the software controller. © 2014 The Author(s). Licensee InTech.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Tampere University of Technology, Department of Intelligent Hydraulics and Automation, Research group: Mobile manipulation, Research group: Field robotics and control, Field robotics for efficient work sites (FIRE)
Contributors: Oftadeh, R., Aref, M. M., Ghabcheloo, R., Mattila, J.
Publication date: 28 Mar 2014
Peer-reviewed: Yes

Publication information

Journal: international Journal of Advanced Robotic Systems
Volume: 11
Issue number: 1
Article number: 51
ISSN (Print): 1729-8806
Ratings: 
  • Scopus rating (2014): CiteScore 1.4 SJR 0.297 SNIP 0.768
Original language: English
ASJC Scopus subject areas: Software, Artificial Intelligence, Computer Science Applications
Keywords: Autonomous vehicles, Mechatronic design, Mobile manipulators, Real-time systems

Bibliographical note

Contribution: organisation=iha,FACT1=1<br/>Portfolio EDEND: 2014-05-30<br/>Publisher name: InTech Open Access Publisher

Source: researchoutputwizard
Source ID: 1179

Research output: Contribution to journalArticleScientificpeer-review

A time-optimal bounded velocity path-following controller for generic Wheeled Mobile Robots

This paper, as a generalization of our previous works, presents a unified time-optimal path-following controller for Wheeled Mobile Robots (WMRs). Unlike other path-following controllers, we solve the path-following problem for all common categories of WMRs such as car-like, differential, omnidirectional, all wheels steerable and others. We show that the insertion of our path-following controller into the kinematic and non-holonomic constraints of the wheels, simplifies the otherwise impenetrable constraints, resulting in explicit monotonic functions between the velocity of the base and that of the wheels. Based on this foundation, we present a closed-form solution that keeps all the wheels' steering and driving velocities within their corresponding pre-specified bounds. Simulation data and experimental results from executing the controller in a real-time environment demonstrate the efficacy of the method.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Intelligent Hydraulics and Automation, Research group: Mobile manipulation, Research group: Field robotics and control
Contributors: Oftadeh, R., Ghabcheloo, R., Mattila, J.
Number of pages: 8
Pages: 676-683
Publication date: 29 Jun 2015

Host publication information

Title of host publication: 2015 IEEE International Conference on Robotics and Automation (ICRA), 26-30 May 2015, Seattle, WA
Publisher: Institute of Electrical and Electronics Engineers IEEE
ISBN (Print): 978-1-4799-6923-4
ASJC Scopus subject areas: Software, Artificial Intelligence, Control and Systems Engineering, Electrical and Electronic Engineering
Source: Scopus
Source ID: 84938244580

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Designing for experiences with socially interactive robots

Socially interactive technologies are emerging as one of the predominant technologies of the future. In this workshop, we aim to discuss the emerging field of Social Robotic technologies with a particular focus on interaction design methodologies used in the design process. The workshop will investigate how researchers have approached designing social robots and what we can learn from the interaction design field for future designs. The main activities of the workshop will encompass two interactive sessions and a discussion panel on approaches to inspire the design of socially interactive robots. In particular, we focus on experience-driven design methods involving rituals and memorable experiences with social robots.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Research area: User experience, Uppsala University, Strate School of Design
Contributors: Obaid, M., Kaipainen, K., Ocnarescu, I., Ahtinen, A.
Number of pages: 4
Pages: 948-951
Publication date: 29 Sep 2018

Host publication information

Title of host publication: NordiCHI 2018 : Revisiting the Life Cycle - Proceedings of the 10th Nordic Conference on Human-Computer Interaction
Publisher: ACM
ISBN (Electronic): 9781450364379
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Design, Social, Social Robot, Technology, User Experience
Source: Scopus
Source ID: 85056571102

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Low-Power Reconfigurable Miniature Sensor Nodes for Condition Monitoring

Wireless sensor networks (WSNs) are being deployed at an escalating rate for various application fields. The ever growing number of application areas requires a diverse set of algorithms with disparate processing needs. WSNs also need to adapt to prevailing energy conditions and processing requirements. The preceding reasons rule out the use of a single fixed design. Instead, a general purpose design that can rapidly be adapted to different conditions and requirements is desired. In lieu of the traditional inflexible wireless sensor node consisting of a separate micro-controller, radio transceiver, sensor array and energy storage, we propose a unified rapidly reconfigurable miniature sensor node, implemented with a transport triggered architecture processor on a low-power Flash FPGA. To our knowledge, this is the first study of its kind. The proposed approach does not solely concentrate on energy efficiency but a high emphasis is also put on the ease of development perspective. Power consumption and silicon area usage comparison based on solutions implemented using our novel rapid design approach for wireless sensor nodes are performed. The comparison is performed between 16-bit fixed point, 16-bit floating point and 32-bit floating point implementations. The implemented processors and algorithms are intended for rolling bearing condition monitoring, but can be fully extended for other applications as well.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Signal Processing Research Community (SPRC), Univ of Oulu, Dept. of Computer Science and Engineering
Contributors: Nyländen, T., Boutellier, J., Nikunen, K., Hannuksela, J., Silvén, O.
Number of pages: 21
Pages: 3-23
Publication date: 2014
Peer-reviewed: Yes

Publication information

Journal: International Journal of Parallel Programming
Volume: 43
Issue number: 1
ISSN (Print): 0885-7458
Ratings: 
  • Scopus rating (2014): CiteScore 1.5 SJR 0.256 SNIP 1.046
Original language: English
ASJC Scopus subject areas: Theoretical Computer Science, Software, Information Systems
Keywords: Application specific processors, Transport triggered architecture, Wireless sensor networks
Source: Scopus
Source ID: 84921701379

Research output: Contribution to journalArticleScientificpeer-review

Serverless: What it Is, What to Do and What Not to Do

Serverless, the new buzzword, has been gaining a lot of attention from the developers and industry. Cloud vendors such as AWS and Microsoft have hyped the architecture almost everywhere, from practitioners' conferences to local events, to blog posts. In this work, we introduce serverless functions (also known as Function-as-a-Service or FaaS), together with on bad practices experienced by practitioners, members of the Tampere Serverless Meetup group.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Gofore Plc
Contributors: Nupponen, J., Taibi, D.
Number of pages: 2
Pages: 49-50
Publication date: 1 Mar 2020

Host publication information

Title of host publication: 2020 IEEE International Conference on Software Architecture Companion, ICSA-C 2020
Publisher: IEEE
ISBN (Electronic): 9781728174150
ASJC Scopus subject areas: Computer Science Applications, Hardware and Architecture, Software, Information Systems and Management
Keywords: FaaS, Function-as-a-service, Serverless
Source: Scopus
Source ID: 85085749334

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Checking visual data flow programs with finite process models

A visual data flow language (VDFL) allows graphical presentation of a computer program in the form of a directed graph, where data tokens travel through the arcs of the graph, and the vertices present e.g. the input token streams, calculations, comparisons, and conditionals. Amongst their benefits, VDFLs allow parallel computing and they are presumed to improve the quality of programming due to their intuitive readability. Thus, they are also suitable for computing education. However, the token-based computational model allowing parallel processing may make the programs more complicated than what they look. We propose a method for checking properties of VDFL programs using finite state processes (FSPs) using a commonly available labelled transition system analyser (LTSA) tool. The method can also be used to study different VDFL programming constructs for development or re-design of VDFLs. For our method, we have implemented a compiler that compiles a textual representation of a VDFL into FSPs.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research Community on Data-to-Decision (D2D), Mathematical modelling with wide societal impact (MathImpact), Ita-Suomen yliopisto
Contributors: Nummenmaa, J., Marttila-Kontio, M., Nummenmaa, T.
Number of pages: 14
Pages: 245-258
Publication date: 2013

Host publication information

Title of host publication: 13th Symposium on Programming Languages and Software Tools, SPLST 2013 - Proceedings
Publisher: University of Szeged
ISBN (Electronic): 9789633062289
ASJC Scopus subject areas: Computer Science Applications, Software
Source: Scopus
Source ID: 84923622331

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Database-driven tool support for DisCo executable specifications

In spite of the advances in theory of formal specifications, they have not gained a wide popularity in the software development industry. This could be due to difficulties in understanding them or positioning them into the current work practices, however, we believe that one major problem is that the tool support still does not make the use of the formal specifications easy enough for the software developer. We discuss the required functionality for comprehensive tool support for executable DisCo specifications, and propose a tool architecture based on database technology, and finally, discuss our implementation of the core part of the tool set.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research Community on Data-to-Decision (D2D), Mathematical modelling with wide societal impact (MathImpact)
Contributors: Nummenmaa, J., Nummenmaa, T.
Number of pages: 11
Pages: 44-54
Publication date: 2011

Host publication information

Title of host publication: SPLST'11 - Proceedings 12th Symposium on Programming Languages and Software Tools
ISBN (Print): 9789949231782
ASJC Scopus subject areas: Computer Science Applications, Software
Source: Scopus
Source ID: 84869824785

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Need to touch, wonder of discovery, and social capital: Experiences with interactive playful seats

In this article we present findings from a design experiment of MurMur Moderators, talking playful seats facilitating playful atmosphere and creativity at office environments. The article describes the design and technological composition of our two prototypes, and our experiences exposing the concept to audiences at science fairs and an office environment. This research has served as an exploratory design study, directing our focus to the seats as primary and secondary play objects with a distinct narrative. Our goal with the initial exposure was to first investigate preliminary audience reactions for the high level concept and how people interact with the prototype. This was then supplemented by testing the concept in an office environment. The data we have collected gives us insight on the seats as primary and secondary play objects and how users touch, discover and socialize.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Mathematical modelling with wide societal impact (MathImpact), RMIT University
Contributors: Nummenmaa, T., Tyni, H., Kultima, A., Alha, K., Holopainen, J.
Publication date: 16 Nov 2015

Host publication information

Title of host publication: ACE 2015 - 12th Advances in Computer Entertainment Technology Conference, Proceedings
Volume: 16-19-November-2015
Publisher: Association for Computing Machinery
Article number: 10
ISBN (Electronic): 9781450338523
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Arduino, Audio feedback, Design research, DIY, Game studies, Internet of things, Office play, Playful furniture, Raspberry Pi
Source: Scopus
Source ID: 84979747766

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

OASIS deck of cards - House of colleagues: A playful

A research experiment to facilitate playful interaction and community learning within an academic organization of about 170 employees was conducted. A 2-player card game including 61 'staff character cards' and 39 question cards was implemented to be played by the relatively new community. The game period, including supporting events, ran for 5 weeks. After the experiment 59 staff members responded to an online survey on play experiences. The results showed that ways of participation and means of play are more diverse in a work community context than as they are specified in the game rules. More emphasis should be set on framing the game and supporting it as a continuous activity to become a playful practice in the work community. An academic community has inherent contextual prerequisites that need to be addressed in order for a playful practice to gain traction as a means for community building.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Mathematical modelling with wide societal impact (MathImpact)
Contributors: Nummenmaa, T., Kultima, A., Kankainen, V., Savolainen, S., Syvänen, A., Alha, K., Mäyrä, F.
Number of pages: 8
Pages: 2-9
Publication date: 22 Sep 2015

Host publication information

Title of host publication: ACADEMICMINDTREK 2015 - Proceedings of the 19th International Academic Mindtrek Conference
Publisher: Association for Computing Machinery, Inc
ISBN (Electronic): 9781450339483
ASJC Scopus subject areas: Human-Computer Interaction, Software, Computer Science Applications
Keywords: Academia, Adult play, Attitudes towards play, Card game, Community, Design, Play at work, Playfulness, University
Source: Scopus
Source ID: 84962803762

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

MurMur Moderators, the talking playful seats

In this article we present the concept of MurMur Moderators, talking playful seats facilitating playful atmosphere and creativity at office environments. The article describes the design and technological composition of our first prototype, and our experiences exposing the concept to audiences at two science fairs in Italy (2013) and Finland (2014). This research has served as an informative pilot study, consequently directing our focus to the ways the accompanying narrative brings additional design value to the interactive seats. Our goal with the fairs was to investigate what are the preliminary audience reactions for the high level concept and how people interact with the initial prototype. The feedback was used for generating further ideas for ambient play and furniture-as-a-service, some of which carries on to future research and second prototype of the seat.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Mathematical modelling with wide societal impact (MathImpact)
Contributors: Nummenmaa, T., Kultima, A., Tyni, H., Alha, K.
Number of pages: 7
Pages: 231-237
Publication date: 4 Nov 2014

Host publication information

Title of host publication: MINDTREK 2014 - Proceedings of the 18th International Academic MindTrek Conference: "Media Business, Management, Content and Services"
Publisher: Association for Computing Machinery, Inc
ISBN (Electronic): 9781450330060
ASJC Scopus subject areas: Computer Science Applications, Human-Computer Interaction, Software
Keywords: Arduino, Audio feedback, Design research, Diy, Game studies, Internet of things, Playful furniture, Raspberry pi
Source: Scopus
Source ID: 84964027379

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Social features in hybrid board game marketing material

This paper identifies 7 key social features which appear in the marketing and promotional material of hybrid board games. The features are identified by exploring sources such as game websites and game boxes of 13 hybrid board game products. The material is analyzed in order to determine how social features related to hybrid game features are presented. As a result of the analysis, it became apparent that there are certain key social features which are presented as being important to players. The knowledge generated in this work acts as a view to how the industry sees hybridity in games as a tool for supporting social interaction, and how the industry wants to message it to consumers when they explore promotional material. The identified key social features can also be used as design knowledge for developing new games, as they give insight into popular social features in hybrid board games.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Tampere University
Contributors: Nummenmaa, T., Kankainen, V.
Publication date: 26 Aug 2019

Host publication information

Title of host publication: Proceedings of the 14th International Conference on the Foundations of Digital Games, FDG 2019
Publisher: ACM
Editors: Khosmood, F., Pirker, J., Apperley, T., Deterding, S.
Article number: 67
ISBN (Electronic): 9781450372176
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Board games, Design, Hybrid games, Marketing

Bibliographical note

INT=comp,"Kankainen, Vill"

Source: Scopus
Source ID: 85072820010

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Effects of directional haptic and non-speech audio cues in a cognitively demanding navigation task

Existing car navigation systems require visual or auditory attention. Providing the driver with directional cues could potentially increase safety. We conducted an experiment comparing directional haptic and non-speech audio cues to visual cueing in a navigation task. Participants (N=16) drove the Lane Change Test simulator with different navigational cues. The participants were to recognize the directional cue (left or right) by responding as fast as possible using a tablet. Reaction times and errors were measured. The participants were also interviewed about the different cues and filled up the NASA-TLX questionnaire. The results showed that in comparison to visual cues all the other cues were reacted to significantly faster. Haptic only cueing resulted in the most errors, but it was evaluated as the most pleasant and the least physically demanding. The results suggest that non-visual cueing could improve safety. Copyright is held by the owner/author(s).

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), School of Management (JKK)
Contributors: Nukarinen, T., Raisamo, R., Farooq, A., Evreinov, G., Surakka, V.
Number of pages: 4
Pages: 61-64
Publication date: 26 Oct 2014

Host publication information

Title of host publication: Proceedings of the NordiCHI 2014: The 8th Nordic Conference on Human-Computer Interaction: Fun, Fast, Foundational
Publisher: Association for Computing Machinery, Inc
ISBN (Electronic): 1595930361, 9781450325424
ASJC Scopus subject areas: Human-Computer Interaction, Software
Keywords: Car navigation, Directional cues, Haptic stimuli, Tactile displays
Source: Scopus
Source ID: 84911368322

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Power mitigation of a heterogeneous multicore architecture on FPGA/ASIC by DFS/DVFS techniques

This article presents an integrated self-aware computing model in a Heterogeneous Multicore Architecture (HMA) to mitigate the power dissipation of an Orthogonal Frequency-Division Multiplexing (OFDM) receiver. The proposed platform consists of template-based Coarse-Grained Reconfigurable Array (CGRA) devices connected through a Network-on-Chip (NoC) around a few Reduced Instruction-Set Computing (RISC) cores. The self-aware computing model exploits Feedback Control System (FCS) which constantly monitors the execution-time of each core and dynamically scales the operating frequency of each node of the NoC depending on the worst execution-time. Therefore, the performance of the overall system is equalized towards a desired level besides mitigating the power dissipation. Measurement results obtained from Field-Programmable Gate Array (FPGA) synthesis show up to 20.2% dynamic power dissipation and 16.8% total power dissipation savings. Since FCS technique can be employed for scaling the frequency and the voltage and on the other hand, voltage supply cannot be scaled on the FPGA-based prototyped platform, the implementation is also estimated in 28nm Ultra-Thin Body and Buried oxide (UTBB) Fully-Depleted Silicon-On-Insulator (FD-SOI) Application-Specific Integrated Circuit (ASIC) technology to scale voltage in addition to frequency and get more benefits in terms of dynamic power dissipation reduction. Subsequent to synthesizing the whole platform on ASIC and scaling the voltage and frequency simultaneously as a Dynamic Voltage and Frequency Scaling (DVFS) method, significant dynamic power dissipation savings by 5.97X against Dynamic Frequency Scaling (DFS) method were obtained.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Electronics and Communications Engineering, Research group: System-on-Chip for GNSS, Wireless Communications and Cyber-Physical Embedded Computing, University of Bologna
Contributors: Nouri, S., Rossi, D., Nurmi, J.
Number of pages: 10
Pages: 259-268
Publication date: 1 Nov 2018
Peer-reviewed: Yes

Publication information

Journal: Microprocessors and Microsystems
Volume: 63
ISSN (Print): 0141-9331
Ratings: 
  • Scopus rating (2018): CiteScore 2.5 SJR 0.264 SNIP 0.941
Original language: English
ASJC Scopus subject areas: Software, Hardware and Architecture, Computer Networks and Communications, Artificial Intelligence
Keywords: Accelerator, ASIC, CGRA, Channel estimation, DVFS, FCS, FFT, FPGA, Frequency offset estimation, Heterogeneous, Multicore, Network-on-Chip, OFDM, Power mitigation, Receiver, Reconfigurable, Time synchronization
Source: Scopus
Source ID: 85054428146

Research output: Contribution to journalArticleScientificpeer-review

Convex Energy Optimization of Streaming Applications for MPSoCs

The energy efficiency of modern MPSoCs is enhanced by complex hardware features such as Dynamic Voltage and Frequency Scaling (DVFS) and Dynamic Power Management (DPM). This paper introduces a new method, based on convex problem solving, that determines the most energy efficient operating point in terms of frequency and number of active cores in an MPSoC. The solution can challenge the popular approaches based on never-idle (or As-Slow-As-Possible (ASAP)) and race-to-idle (or As-Fast-As-Possible (AFAP)) principles. Experimental data are reported using a Samsung Exynos 5410 MPSoC and show a reduction in energy of up to 27 % when compared to ASAP and AFAP.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, Universite de Rennes
Contributors: Nogues, E., Mercat, A., Arrestier, F., Pelcat, M., Menard, D.
Number of pages: 5
Pages: 1557-1561
Publication date: 1 May 2019

Host publication information

Title of host publication: 2019 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2019 - Proceedings
Publisher: IEEE
ISBN (Electronic): 9781479981311
ASJC Scopus subject areas: Software, Signal Processing, Electrical and Electronic Engineering
Source: Scopus
Source ID: 85068997223

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

A quasi-virtual online analyser based on an artificial neural networks and offline measurements to predict purities of raffinate/extract in simulated moving bed processes

The quality control and optimization of Simulated Moving Bed processes are still a challenge. Among the main reasons for that, the real time measurement of its main properties can be highlighted. Further developments in this field are necessary in order to allow the development of better control and optimization systems of these units. In the present work, a system composed by two Artificial Neural Networks working concomitantly with an offline measurement system is proposed, named Quasi-Virtual Analyser (Q-VOA) system. The development of the Q-VOA is presented and the system is simulated in order to evaluate its efficiency. The methodology used to select the input variables for the Q-VOA is another contribution of this work. The results show that the Q-VOA is capable of reducing the system errors and keep the prediction closer to the process true responses, when compared with the simple VOA system, which is based solely on model predictions. Furthermore, the results show the efficiency of the measurement system even under the presence of non-measured perturbations.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Automation and Hydraulic Engineering, Univ Porto, Universidade do Porto, Fac Med, Dept Med Imaging, Federal Univ. of Bahia
Contributors: Nogueira, I. B., Ribeiro, A. M., Requião, R., Pontes, K. V., Koivisto, H., Rodrigues, A. E., Loureiro, J. M.
Number of pages: 19
Pages: 29-47
Publication date: 1 Jun 2018
Peer-reviewed: Yes

Publication information

Journal: Applied Soft Computing Journal
Volume: 67
ISSN (Print): 1568-4946
Ratings: 
  • Scopus rating (2018): CiteScore 8.9 SJR 1.216 SNIP 2.474
Original language: English
ASJC Scopus subject areas: Software
Keywords: Artificial neural network, Enantiomers separation, Purity measurement, Quasi-virtual analyser system, True moving bed
Source: Scopus
Source ID: 85043383206

Research output: Contribution to journalArticleScientificpeer-review

Estimation of time-varying room impulse responses of multiple sound sources from observed mixture and isolated source signals

This paper proposes a method for online estimation of time-varying room impulse responses (RIR) between multiple isolated sound sources and a far-field mixture. The algorithm is formulated as adaptive convolutive filtering in short-time Fourier transform (STFT) domain. We use the recursive least squares (RLS) algorithm for estimating the filter parameters due to its fast convergence rate, which is required for modeling rapidly changing RIRs of moving sound sources. The proposed method allows separation of reverberated sources from the far-field mixture given that their close-field signals are available. The evaluation is based on measuring unmixing performance (removal of reverberated source) using objective separation criteria calculated between the ground truth recording of the preserved sources and the unmixing result obtained with the proposed algorithm. We compare online and offline formulations for the RIR estimation and also provide evaluation with blind source separation algorithm only operating on the mixture signal.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing, Research group: Audio research group - ARG
Contributors: Nikunen, J., Virtanen, T.
Number of pages: 5
Pages: 421-425
Publication date: 10 Sep 2018

Host publication information

Title of host publication: 2018 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2018 - Proceedings
Volume: 2018-April
Publisher: Institute of Electrical and Electronics Engineers Inc.
Article number: 8462535
ISBN (Print): 9781538646588

Publication series

Name:  Proceedings of the IEEE International Conference on Acoustics, Speech, and Signal Processing
ISSN (Electronic): 2379-190X
ASJC Scopus subject areas: Software, Signal Processing, Electrical and Electronic Engineering
Keywords: Adaptive filtering, Informed source separation, Online room impulse response estimation, Source unmixing

Bibliographical note

jufoid=57409

Source: Scopus
Source ID: 85054234348

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Social human-robot interaction in the wild: A workshop proposal for academic mindtrek 2020

This workshop will collect experts and stakeholders from all fields of human-robot interaction: both social and industrial applications and uses of robotics are of interest as far as they have human in the loop. The workshop will present recent and fully new research work in social HRI, including first results of a 3.5 month field trial and mixed-method study of a social robot Pepper in a shopping mall in Finland.

General information

Publication status: Published
MoE publication type: B3 Non-refereed article in conference proceedings
Organisations: Computing Sciences, Tampere University, VTT Technical Research Centre of Finland
Contributors: Niemelä, M., Ahtinen, A., Turunen, M.
Number of pages: 2
Pages: 168-169
Publication date: 29 Jan 2020

Host publication information

Title of host publication: AcademicMindtrek 2020 - Proceedings of the 23rd International Academic Mindtrek Conference : January 2020, Tampere
Publisher: ACM
ISBN (Electronic): 9781450377744
ASJC Scopus subject areas: Software, Human-Computer Interaction, Computer Vision and Pattern Recognition, Computer Networks and Communications
Keywords: collaborative robots, human-robot interaction, social robots

Bibliographical note

INT=comp,"Turunen, Markku"

Source: Scopus
Source ID: 85080870105

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientific

LTE indoor MIMO performances field measurements

Long-term evolution (LTE) and multiple input multiple output (MIMO) have earned reputations to be a cutting-edge technology, which can boost significantly wireless communication performances. The paper aims at providing LTE MIMO performances in indoor environments and, therefore, guidelines for network operators can be proposed. Medium access control throughput (MAC TP) and some system parameters in LTE network that are linked with MAC TP, such as Channel Quality Indicator (CQI), Modulation and Coding Scheme (MCS), Ranking Indicator (RI), Pre-coding Matrix Indicator (PMI), as well as MIMO utilization, are analysed. Effects of indoor propagation, Line of Sight (LoS), No-line of Sight (NLoS), strong and weak signal levels on Signal to Noise Radio (SNR) strength and MIMO utilization are clarified. In this paper, the performances of MIMO transmission mode over transmit diversity (TxDiv, Multiple Input-Single Output-MISO) and single antenna (Single Input Multiple Output-SIMO) modes are also analyzed and compared at overall manner and at channel-specific manners.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Tampere University of Technology, Department of Electronics and Communications Engineering, Department of Electronics and Communication Engineering, Electrical and Electronics Engineering Department, Department of Electric-Electronics Engineering, Ho Chi Minh City University of Technology, Industrial University of Ho Chi Minh City, Ho Chi Minh City University of Food Industry
Contributors: Nguyen-Thanh, D., Le-Tien, T., Bui-Thu, C., Le-Thanh, T.
Number of pages: 6
Pages: 84-89
Publication date: 17 Feb 2015

Host publication information

Title of host publication: International Conference on Advanced Technologies for Communications
Publisher: IEEE
ISBN (Print): 9781479969555
ASJC Scopus subject areas: Computer Networks and Communications, Hardware and Architecture, Software
Keywords: Field measurements, LTE, MIMO, MISO, OFDM, Rayleigh channel, Rician channel

Bibliographical note

INT=elt,"Nguyen-Thanh, Duc"

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Ensembles of dense and dense sampling descriptors for the HEp-2 cells classification problem

The classification of Human Epithelial (HEp-2) cells images, acquired through Indirect Immunofluorescence (IIF) microscopy, is an effective method to identify staining patterns in patient sera. Indeed it can be used for diagnostic purposes, in order to reveal autoimmune diseases. However, the automated classification of IIF HEp-2 cell patterns represents a challenging task, due to the large intra-class and the small inter-class variability. Consequently, recent HEp-2 cell classification contests have greatly spurred the development of new IIF image classification systems.Here we propose an approach for the automatic classification of IIF HEp-2 cell images by fusion of several texture descriptors by ensemble of support vector machines combined by sum rule. Its effectiveness is evaluated using the HEp-2 cells dataset used for the "Performance Evaluation of Indirect Immunofluorescence Image Analysis Systems" contest, hosted by the International Conference on Pattern Recognition in 2014: the accuracy on the testing set is 79.85%.The same dataset was used to test an ensemble of ternary-encoded local phase quantization descriptors, built by perturbation approaches: the accuracy on the training set is 84.16%. Finally, this ensemble was validated on 14 additional datasets, obtaining the best performance on 11 datasets.Our MATLAB code is available at https://www.dei.unipd.it/node/2357.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Electronics and Communications Engineering, Research group: Computational Biophysics and Imaging Group, BioMediTech, Integrated Technologies for Tissue Engineering Research (ITTE), Universita degli Studi di Padova, Italy, University of Bologna
Contributors: Nanni, L., Lumini, A., dos Santos, F. L. C., Paci, M., Hyttinen, J.
Pages: 28-35
Publication date: 15 Oct 2016
Peer-reviewed: Yes

Publication information

Journal: Pattern Recognition Letters
Volume: 82
ISSN (Print): 0167-8655
Ratings: 
  • Scopus rating (2016): CiteScore 5.2 SJR 0.729 SNIP 1.678
Original language: English
ASJC Scopus subject areas: Software, Artificial Intelligence, Computer Vision and Pattern Recognition, Signal Processing
Keywords: Bag-of-features, Ensemble, HEp-2 cell classification, Machine learning, Support vector machine, Texture descriptors
URLs: 
Source: Scopus
Source ID: 84961195136

Research output: Contribution to journalArticleScientificpeer-review

Mobiscool: 1st workshop on mobile, social and culturally oriented learning

There are two simultaneous transformative changes occuring in Education: the use of mobile and tablet devices for accessing educational content, and the rise of the MOOCs. Happening independently and in parallel are significant advances in interaction technologies through smartphones and tablets, and the rise in the use of social-media and social-network analytics in several domains. Given the extent of personal context that is available on the mobile device, how can the education experience be personalised, made social, and tailored to the cultural context of the learner? The goal of this proposal is twofold: (a) To understand the usage, and student behaviour in this new environment (MOOCS and mobile devices) and (b) To design experiments and implement them to make these new tools more effective by tailoring them to the individual student's personal, social and cultural settings and preferences.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), IBM Research, Aalborg University
Contributors: Nanavati, A. A., Rajput, N., Turunen, M., Knoche, H., Rehm, M.
Number of pages: 4
Pages: 1187-1190
Publication date: 24 Aug 2015

Host publication information

Title of host publication: MobileHCI 2015 - Proceedings of the 17th International Conference on Human-Computer Interaction with Mobile Devices and Services Adjunct
Publisher: Association for Computing Machinery, Inc
ISBN (Electronic): 9781450336536
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Information Systems, Software
Keywords: Augmented reality, Behaviour, Culture, Education, MOOCs, Multimedia, Social media, Social network analysis, User experience
Source: Scopus
Source ID: 84962791832

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

SiMPE: 8th workshop on speech and sound in mobile and pervasive environments

The SiMPE workshop series started in 2006 with the goal of enabling speech processing on mobile and embedded devices. The SiMPE 2012 workshop extended the notion of audio to non-speech "Sounds" and thus the expansion became "Speech and Sound". SiMPE 2010 and 2011 brought together researchers from the speech and the HCI communities. Speech User interaction in cars was a focus area in 2009. Multimodality got more attention in SiMPE 2008. In SiMPE 2007, the focus was on developing regions. With SiMPE 2013, the 8th in the series, we continue to explore the area of speech along with sound. Akin to language processing and text-to-speech synthesis in the voice-driven interaction loop, sensors can track continuous human activities such as singing, walking, or shaking the mobile phone, and non-speech audio can facilitate continuous interaction. The technologies underlying speech processing and sound processing are quite different and these communities have been working mostly independent of each other. And yet, for multimodal interactions on the mobile, it is perhaps natural to ask whether and how speech and sound can be mixed and used more effectively and naturally.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), IBM Research, Ita-Suomen yliopisto, University of Helsinki, Carnegie Mellon University, Aalborg University
Contributors: Nanavati, A. A., Rajput, N., Srivastava, S., Erkut, C., Jylhä, A., Rudnicky, A. I., Serafin, S., Turunen, M.
Number of pages: 4
Pages: 626-629
Publication date: 2013

Host publication information

Title of host publication: MobileHCI 2013 - Proceedings of the 15th International Conference on Human-Computer Interaction with Mobile Devices and Services
ISBN (Print): 9781450322737
ASJC Scopus subject areas: Human-Computer Interaction, Software
Keywords: mobile computing, sonic interaction, sound, sound and music computing, speech processing
Source: Scopus
Source ID: 84883727754

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

SiMPE: 7th Workshop on speech and sound in mobile and pervasive environments

The SiMPE workshop series started in 2006 [2] with the goal of enabling speech processing on mobile and embedded devices to meet the challenges of pervasive environments (such as noise) and leveraging the context they offer (such as location). SiMPE 2010 and 2011 brought together researchers from the speech and the HCI communities. Multimodality got more attention in SiMPE 2008 than it had received in the previous years. In SiMPE 2007, the focus was on developing regions. Speech User interaction in cars was a focus area in 2009. With SiMPE 2012, the 7th in the series, we hope to explore the area of speech along with sound. When using the mobile in an eyes-free manner, it is natural and convenient to hear about notifications and events. The arrival of an SMS has used a very simple sound based notification for a long time now. The technologies underlying speech processing and sound processing are quite different and these communities have been working mostly independent of each other. And yet, for multimodal interactions on the mobile, it is perhaps natural to ask whether and how speech and sound can be mixed and used more effectively and naturally.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), IBM Research, Carnegie Mellon University, HP Laboratories, National Research Council, University of Toronto, Canada
Contributors: Nanavati, A. A., Rajput, N., Rudnicky, A. I., Turunen, M., Sandholm, T., Munteanu, C., Penn, G.
Number of pages: 3
Pages: 251-253
Publication date: 2012

Host publication information

Title of host publication: MobileHCI'12 - Companion Proceedings of the 14th International Conference on Human Computer Interaction with Mobile Devices and Services
ISBN (Print): 9781450311052
ASJC Scopus subject areas: Computer Networks and Communications, Human-Computer Interaction, Information Systems, Software
Keywords: Audio interaction, Mobile computing, Pervasive computing, Sound, Speech processing
Source: Scopus
Source ID: 84867703942

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Optimized viewport dependent streaming of stereoscopic omnidirectional video

Streaming the whole omnidirectional video at high quality is less efficient in terms of bandwidth requirements and decoding complexity, since only a small part of the 360-degree horizontal field of view can be seen by a user at a given point in time. In Viewport Dependent Streaming (VDS) only the current user viewport is streamed at high quality, while the remaining parts are streamed at lower quality. This technology may save streaming bandwidth considerably, especially when it is associated to other techniques. Among the others, asymmetric stereoscopic video, has been studied in the past for traditional video and displays. We focused our research on the usage of asymmetric stereoscopic video for omnidirectional streams watched with a Head Mounted Display (HMD) in VDS. We conducted two subjective quality experiments with the main goal of reducing the streaming bandwidth, while keeping the subjective video quality at the highest level. We assessed asymmetric video applied separately to the foreground and background views of omnidirectional VDS sessions. We show that for VDS, applying asymmetric stereoscopic streaming delivery on the foreground view can save up to 41% bit rate, and using the same technique on the background view can save approximately up to 15% bit rate. Furthermore, eye dominance was seen not to be relevant in our experiments.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing, Nokia Technologies
Contributors: Naik, D., Curcio, I. D., Toukomaa, H.
Number of pages: 6
Pages: 37-42
Publication date: 12 Jun 2018

Host publication information

Title of host publication: Proceedings of the 23th ACM Workshop on Packet Video, PV 2018
Publisher: ACM
ISBN (Electronic): 9781450357739
ASJC Scopus subject areas: Human-Computer Interaction, Software
Keywords: 360 degrees video, Asymmetric video, Omnidirectional video, Streaming adaptation, Subjective quality evaluation, Virtual reality streaming

Bibliographical note

EXT="Curcio, Igor D.D."

Source: Scopus
Source ID: 85050644603

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Challenges in developing data-based value creation

Understanding data-based value creation helps organizations to enhance its decision-making and to renew their business operations. However, organizations aiming to use modern data analytics face several severe challenges that are not usually so evident or visible beforehand. In this paper we study a Finnish manufacturing company's data empowerment and information and knowledge management practices in order to identify the potential challenges related to modern data-based value creation within industrial context. The empirical data is consisted of group discussions, relevant data sets acquired from the case company's information systems, and lastly, 12 thematic interviews of the key actors in the company in relation to service development. The study provides valuable insights for managing service development and decision-making and creates understanding on data-based value creation. Achieved understanding provides meaningful knowledge for organizations utilizing or having plans to utilize, for example, data analytic methods in their businesses.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Information and Knowledge Management
Contributors: Myllärniemi, J., Helander, N., Pekkola, S.
Number of pages: 7
Pages: 370-376
Publication date: 2019

Host publication information

Title of host publication: IC3K 2019 - Proceedings of the 11th International Joint Conference on Knowledge Discovery, Knowledge Engineering and Knowledge Management
Publisher: SCITEPRESS
Editors: Bernardino, J., Salgado, A., Filipe, J.
ISBN (Electronic): 9789897583827

Publication series

Name: IC3K 2019 - Proceedings of the 11th International Joint Conference on Knowledge Discovery, Knowledge Engineering and Knowledge Management
Volume: 3
ASJC Scopus subject areas: Software
Keywords: Case Study, Data-based Value Creation, Information Management Process, Knowledge Management

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Exploiting subclass information in one-class support vector machine for video summarization

In this paper, we propose a method for video summarization based on human activity description. We formulate this problem as the one of automatic video segment selection based on a learning process that employs salient video segment paradigms. For this one-class classification problem, we introduce a novel variant of the One-Class Support Vector Machine (OC-SVM) classifier that exploits subclass information in the OC-SVM optimization problem, in order to jointly minimize the data dispersion within each subclass and determine the optimal decision function. We evaluate the proposed approach in three Hollywood movies, where the performance of the proposed SOC-SVM algorithm is compared with that of the OC-SVM. Experimental results denote that the proposed approach is able to outperform OC-SVM-based video segment selection.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research Community on Data-to-Decision (D2D), Aristotle University of Thessaloniki
Contributors: Mygdalis, V., Iosifidis, A., Tefas, A., Pitas, I.
Number of pages: 5
Pages: 2259-2263
Publication date: 4 Aug 2015

Host publication information

Title of host publication: ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings
Volume: 2015-August
Publisher: The Institute of Electrical and Electronics Engineers, Inc.
ISBN (Print): 9781467369978
ASJC Scopus subject areas: Signal Processing, Software, Electrical and Electronic Engineering
Keywords: One class classification, Subclass One-Class SVM, Supervised Video Summarization
Source: Scopus
Source ID: 84945586271

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Children designing videos: Tools, pedagogical models, and best practices for digital storytelling and media-making in the classroom

Although video sharing is common among youth, schools are only beginning to apply digital videos and digital storytelling to formal learning. This paper presents pedagogical models, examples, best practices, and outcomes that illustrate how teachers and students design and use digital stories in knowledge creation in cross-cultural settings. The results are based on the empirical data and findings from several international pilot studies. On the one hand, working with digital video stories drove engagement. However, on the other hand, technical issues significantly lowered engagement. In addition, the video inquiry pedagogy supported inquiry learning. Students began to pose scientifically oriented questions and seek answers together.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Research group: TUT Game Lab, Pervasive Computing, University of Helsinki, Pepperdine University
Contributors: Multisilta, J., Niemi, H., Hamilton, E.
Number of pages: 4
Pages: 693-696
Publication date: 27 Jun 2017

Host publication information

Title of host publication: IDC 2017 - Proceedings of the 2017 ACM Conference on Interaction Design and Children
Publisher: ACM
ISBN (Electronic): 9781450349215
ASJC Scopus subject areas: Software, Education, Human-Computer Interaction, Developmental and Educational Psychology
Keywords: Children, Media-making, Pedagogical models, STEM, Storytelling, Video
Source: Scopus
Source ID: 85026309191

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Controlled experiments comparing fault-tree-based safety analysis techniques

The capability to model dynamic aspects of safety-critical systems, such as sequence or stochastic dependence of events, is one important requirement for safety analysis techniques. State Event Fault Tree Analysis, Dynamic Fault Tree Analyis, and Fault Tree Analysis combined with Markov Chains Analysis have been developed to fulfill these requirements, but they are still not widely accepted and used in practice. In order to investigate the reasons behind this low usage, we conducted two controlled experiments. The goal of the experiments was to analyze and compare applicability and efficiency in State Event Fault Tree analysis versus Dynamic Fault Tree Analyis and Fault Tree Analysis combined with Markov Chains Analysis. The results of both experiments show that, notwithstanding the power of State Event Fault Tree Analysis, Dynamic Fault Tree Analyis is rated by participants as more applicable and is more efficient compared to State Event Fault Tree Analysis, which, in turn, is rated as more applicable but is less efficient than Fault Tree Analysis combined with Markov Chains Analysis. Two of the reasons investigated are the complexity of the notations used and the lack of tool support. Based on these results, we suggest strategies for enhancing State Event Fault Tree Analysis to overcome its weaknesses and increase its applicability and efficiency in modeling dynamic aspects of safety-critical systems.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: University of Kaiserslautern, Former organisation of the author
Contributors: Mouaffo, A., Taibi, D., Jamboti, K.
Publication date: 2014

Host publication information

Title of host publication: 18th International Conference on Evaluation and Assessment in Software Engineering, EASE 2014
Publisher: Association for Computing Machinery (ACM)
Article number: a46
ISBN (Print): 9781450324762
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Controlled experiment, Dynamic fault tree, Fault tree analysis, Markov chain, Safety-analysis, Safety-critical systems, State event fault tree
Source: Scopus
Source ID: 84905483353

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Gamified crowdsourcing: Conceptualization, literature review, and future agenda

Two parallel phenomena are gaining attention in human–computer interaction research: gamification and crowdsourcing. Because crowdsourcing's success depends on a mass of motivated crowdsourcees, crowdsourcing platforms have increasingly been imbued with motivational design features borrowed from games; a practice often called gamification. While the body of literature and knowledge of the phenomenon have begun to accumulate, we still lack a comprehensive and systematic understanding of conceptual foundations, knowledge of how gamification is used in crowdsourcing, and whether it is effective. We first provide a conceptual framework for gamified crowdsourcing systems in order to understand and conceptualize the key aspects of the phenomenon. The paper's main contributions are derived through a systematic literature review that investigates how gamification has been examined in different types of crowdsourcing in a variety of domains. This meticulous mapping, which focuses on all aspects in our framework, enables us to infer what kinds of gamification efforts are effective in different crowdsourcing approaches as well as to point to a number of research gaps and lay out future research directions for gamified crowdsourcing systems. Overall, the results indicate that gamification has been an effective approach for increasing crowdsourcing participation and the quality of the crowdsourced work; however, differences exist between different types of crowdsourcing: the research conducted in the context of crowdsourcing of homogenous tasks has most commonly used simple gamification implementations, such as points and leaderboards, whereas crowdsourcing implementations that seek diverse and creative contributions employ gamification with a richer set of mechanics.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Research group: TUT Game Lab, Pervasive Computing, Robert Bosch GmbH, Karlsruhe Institute of Technology, Insitute for Technical Physics, Germany, Gamification Group
Contributors: Morschheuser, B., Hamari, J., Koivisto, J., Maedche, A.
Number of pages: 18
Pages: 26-43
Publication date: 1 Oct 2017
Peer-reviewed: Yes

Publication information

Journal: International Journal of Human-Computer Studies
Volume: 106
ISSN (Print): 1071-5819
Ratings: 
  • Scopus rating (2017): CiteScore 5.9 SJR 0.605 SNIP 2.146
Original language: English
ASJC Scopus subject areas: Human Factors and Ergonomics, Software, Education, Engineering(all), Human-Computer Interaction, Hardware and Architecture
Keywords: Crowdsourcing, Gamification, Human computation, Literature review, Persuasive technology, Research agenda
Source: Scopus
Source ID: 85019568466

Research output: Contribution to journalArticleScientificpeer-review

How to design gamification? A method for engineering gamified software

Context: Since its inception around 2010, gamification has become one of the top technology and software trends. However, gamification has also been regarded as one of the most challenging areas of software engineering. Beyond traditional software design requirements, designing gamification requires the command of disciplines such as (motivational/behavioral) psychology, game design, and narratology, making the development of gamified software a challenge for traditional software developers. Gamification software inhabits a finely tuned niche of software engineering that seeks for both high functionality and engagement; beyond technical flawlessness, gamification has to motivate and affect users. Consequently, it has also been projected that most gamified software is doomed to fail. Objective: This paper seeks to advance the understanding of designing gamification and to provide a comprehensive method for developing gamified software. Method: We approach the research problem via a design science research approach; firstly, by synthesizing the current body of literature on gamification design methods and by interviewing 25 gamification experts, producing a comprehensive list of design principles for developing gamified software. Secondly, and more importantly, we develop a detailed method for engineering of gamified software based on the gathered knowledge and design principles. Finally, we conduct an evaluation of the artifacts via interviews of ten gamification experts and implementation of the engineering method in a gamification project. Results: As results of the study, we present the method and key design principles for engineering gamified software. Based on the empirical and expert evaluation, the developed method was deemed as comprehensive, implementable, complete, and useful. We deliver a comprehensive overview of gamification guidelines and shed novel insights into the nature of gamification development and design discourse. Conclusion: This paper takes first steps towards a comprehensive method for gamified software engineering.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Research group: TUT Game Lab, Pervasive Computing, University of Duisburg-Essen
Contributors: Morschheuser, B., Hassan, L., Werder, K., Hamari, J.
Pages: 219-237
Publication date: 2018
Peer-reviewed: Yes
Early online date: 2017

Publication information

Journal: Information and Software Technology
Volume: 95
ISSN (Print): 0950-5849
Ratings: 
  • Scopus rating (2018): CiteScore 7.9 SJR 0.615 SNIP 3.085
Original language: English
ASJC Scopus subject areas: Software, Information Systems, Computer Science Applications
Keywords: Design science research, Game design, Gameful design, Gamification, Persuasive technology, Playfulness, Software engineering
Source: Scopus
Source ID: 85035150495

Research output: Contribution to journalArticleScientificpeer-review

Towards certifying the testing process of open-source software: New challenges or old methodologies?

To improve both the quality and the trustworthiness perception of Open Source Software (OSS) products, we introduce the new idea of certifying the testing process of an OSS system. While the global certification of an OSS product is an emerging research field, the idea of certifying only its testing process has never been studied, conversely to the case of Closed Source Software (CSS) products. The certification of the testing process has a twofold goal: simplify the process of testing OSS products by guiding developers in identifying the proper testing strategies and the limitations of their existing testing plans; simplify the selection of equivalent OSS and CSS products by evaluating the certificates released by the companies. Specifically, in this paper we discuss 1) a set of issues, inherent to OSS, that must be taken into account when testing the OSS product; 2) a preliminary methodology that suggests how to certificate the testing process of OSS products; 3) the BusyBox case study that shows how our idea can be applied to real-life OSS.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Università degli Studi Dell'Insubria, Former organisation of the author
Contributors: Morasca, S., Taibi, D., Tosi, D.
Number of pages: 6
Pages: 25-30
Publication date: 2009

Host publication information

Title of host publication: Proceedings of the 2009 ICSE Workshop on Emerging Trends in Free/Libre/Open Source Software Research and Development, FLOSS 2009
Article number: 5071356
ISBN (Print): 9781424437207
ASJC Scopus subject areas: Computer Science Applications, Information Systems, Software
Source: Scopus
Source ID: 70349739151

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Guidelines for improving the testing process of open source software

Open Source Software (OSS) products do not usually follow traditional software engineering development paradigms. Specifically, testing activities in OSS development may be quite different from those carried out in Closed Source Software (CSS) development. As testing and verification require a good deal of resources in OSS, it is necessary to have ways to assess and improve OSS testing processes. This paper provides a set of testing guidelines and issues that OSS developers can use to decide which testing techniques make most sense for their OSS products. This paper 1) provides a checklist that helps OSS developers identify the most useful testing techniques according to the main characteristics of their products, and 2) outlines a proposal for a method that helps assess the maturity of OSS testing processes. The method is a proposal of a Maturity Model for testing processes (called OSS-TMM). To show its usefulness, the authors apply the method to seven real-life projects. Specifically, the authors apply the method to BusyBox, Apache Httpd, and Eclipse Test & Performance Tools Platform to show how the checklist supports and guides the testing process of these OSS products.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Università degli Studi Dell'Insubria
Contributors: Morasca, S., Taibi, D., Tosi, D.
Number of pages: 22
Pages: 1-22
Publication date: Apr 2011
Peer-reviewed: Yes

Publication information

Journal: International Journal of Open Source Software and Processes
Volume: 3
Issue number: 2
ISSN (Print): 1942-3926
Ratings: 
  • Scopus rating (2011): CiteScore 0.5 SJR 0.141 SNIP 0.777
Original language: English
ASJC Scopus subject areas: Software
Keywords: Open Source Software (OSS) Quality, Survey, Testing Process, Testing Quality Assessment, Trustworthiness
Source: Scopus
Source ID: 84860503937

Research output: Contribution to journalArticleScientificpeer-review

Configuring and visualizing the data resources in a cloud-based data collection framework

The Manufacturing Enterprise Solutions Association (MESA) provided the abstract and general definition of the Manufacturing Execution Systems (MES). A dedicated function has been reserved for the data collection activities. In this matter, the Cloud Collaborative Manufacturing Networks (C2NET) project tends to provide a cloud based platform for hosting the interactions of the supply chain in a collaborative network. Within the architecture of the C2NET project, a Data Collection Framework (DCF) is designed to fulfill the function of data collection. This allows the companies to provide their data, which can be both enterprise and Internet of Things (IoT) devices type of data to the platform for further use. The collection of the data is achieved by a specific third party application, i.e., the Legacy System Hub (LSH). This research work presents the approach of configuring and visualizing the data resources in the C2NET platform. This approach employs the web-based applications and the help of the LSH. This permits the C2NET platform to adapt to any kind of third party application, which manipulates enterprise data, following the generic and flexible solution of this approach.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Automation and Hydraulic Engineering, Research group: Automation and Systems Theory, Instituto de Desenvolvimento de Novas Tecnologias
Contributors: Mohammed, W. M., Ferrer, B. R., Jose, L., Lastra, M., Aleixo, D., Agostinho, C.
Number of pages: 8
Pages: 1201-1208
Publication date: 2 Feb 2018

Host publication information

Title of host publication: 2017 International Conference on Engineering, Technology and Innovation : Engineering, Technology and Innovation Management Beyond 2020: New Challenges, New Approaches, ICE/ITMC 2017 - Proceedings
Publisher: IEEE
ISBN (Electronic): 9781538607749
ASJC Scopus subject areas: Computer Science Applications, Software, Engineering (miscellaneous), Computer Networks and Communications
Keywords: Cloud Based, Data Collection, Data Resources, Supply Chain, Visualization

Bibliographical note

INT=aut,"Jose, L."

Source: Scopus
Source ID: 85047476305

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

A multi-agent approach for processing industrial enterprise data

The C2NET project aims to provide cloud-based platform for the supply chain interactions. The architecture of such platform includes a Data Collection Framework (DCF) for managing the collection of the company's data. The DCF collects, transforms and stores data from both Internet of Things (IoT) devices in the factory shopfloor and company enterprises data via two types of hub; Legacy system hub (LSH) and IoT hub. Since the C2NET, targets the Small and Medium-sized Enterprises (SMEs), the enterprise data, or legacy data as called in the C2NET project, can be provided via excel files. Thus, this research work highlights a technique for processing the excel files in the LSHs. This technique adopts the concept of Multi-Agent Systems for processing the data as table in the excel files in the LSH. The multi-agent approach allows the LSH to process any excel file regardless the complexity in the data structure or in the file table. Furthermore, the presented approach enhances the processing of the excel files in different aspects, such as the size of the excel file or the required processing power.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Automation and Hydraulic Engineering, Research group: Automation and Systems Theory, Universitat Politècnica de València, Instituto de Desenvolvimento de Novas Tecnologias
Contributors: Mohammed, W. M., Ferrer, B. R., Martinez, J. L., Sanchis, R., Andres, B., Agostinho, C.
Number of pages: 7
Pages: 1209-1215
Publication date: 2 Feb 2018

Host publication information

Title of host publication: 2017 International Conference on Engineering, Technology and Innovation : Engineering, Technology and Innovation Management Beyond 2020: New Challenges, New Approaches, ICE/ITMC 2017 - Proceedings
Publisher: IEEE
ISBN (Electronic): 9781538607749
ASJC Scopus subject areas: Computer Science Applications, Software, Engineering (miscellaneous), Computer Networks and Communications
Keywords: Cloud Based, Data Collection, Enterprise, Multi-Agent Systems, supply Chain
Source: Scopus
Source ID: 85047492606

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Barriers for bridging interpersonal gaps: Three inspirational design patterns for increasing collocated social interaction

Positive face-to-face social encounters between strangers can strengthen the sense of community in modern urban environments. However, it is not always easy to initiate friendly encounters due to various inhibiting social norms. We present three inspirational design patterns for reducing inhibitions to interact with unfamiliar others. These abstractions are based on a broad design space review of concepts, encompassing examples across a range of scales, fields, media and forms. Each inspirational pattern is formulated as a response to a different challenge to initiating social interaction but all share an underlying similarity in offering varieties of barriers and filters that paradoxically also separate people. The patterns are "Closer Through Not Seeing"; "Closer Through Not Touching"; and "Minimize Encounter Duration". We believe these patterns can support designers, in understanding, articulating, and generating approaches to creating embodied interventions and systems that enable unacquainted people to interact.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Pervasive Computing, Research area: User experience, University of Southern Denmark
Contributors: Mitchell, R., Olsson, T.
Number of pages: 9
Pages: 2-10
Publication date: 26 Jun 2017

Host publication information

Title of host publication: C&T 2017 - 8th International Conference on Communities and Technologies, Conference Proceedings
Publisher: ACM
ISBN (Electronic): 9781450348546
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Collocated interaction, Face-to-face interaction, Social interaction design, pattern languages, embodied interaction
Source: Scopus
Source ID: 85025125983

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Facilitating the first move: Exploring inspirational design patterns for aiding initiation of social encounters

Actualizing positive social encounters remains both a key ends and means in many activities to foster a sense of community. Initiating encounters between strangers typically requires facilitative activities or artefacts, such as icebreakers or tickets-to-talk. However, there is little understanding of which designs are effective and why, and the broad design space remains largely underexplored. We address this challenge by presenting five candidates for inspirational design patterns on signaling social intentions and identifying impediments that deter commencement of encounters. The principles result from an extensive review of design cases and public art installations. Through focus groups and expert interviews, we assessed the perceived applicability and social acceptance of the proposed patterns. Three new design principles relating to the risks of initiating an encounter emerged through analyzing participant responses. These articulations of possible approaches and pitfalls for increasing conviviality may broaden the repertoire of, and support discussion between designers and others concerned with collocated social interaction.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences, University of Southern Denmark
Contributors: Mitchell, R., Olsson, T.
Number of pages: 12
Pages: 283-294
Publication date: 3 Jun 2019

Host publication information

Title of host publication: C&T 2019 - 9th International Conference on Communities and Technologies, Conference Proceedings
Publisher: ACM
Editors: Tellioglu, H., Cech, F.
ISBN (Electronic): 9781450371629
ASJC Scopus subject areas: Human-Computer Interaction, Computer Networks and Communications, Computer Vision and Pattern Recognition, Software
Keywords: Collocated interaction, Design patterns, Social encounters, Social encouragement, Social interaction design, Ticket-to-talk
Source: Scopus
Source ID: 85067884637

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Compression of signs of DCT coefficients for additional lossless compression of JPEG images

One of the main approaches to additional lossless compression of JPEG images is decoding of quantized values of discrete cosine transform (DCT) coefficients and further more effective recompression of the coefficients. Values of amplitudes of DCT coefficients are highly correlated and it is possible to effectively compress them. At the same time, signs of DCT coefficients, which occupy up to 20% of compressed image, are often considered unpredictable. In the paper, a new and effective method for compression of signs of quantized DCT coefficients is proposed. The proposed method takes into account both correlation between DCT coefficients of the same block and correlation between DCT coefficients of neighbor blocks. For each of 64 DCT coefficients, positions of 3 reference coefficients inside the block are determined and stored in the compressed file. Four reference coefficients with fixed positions are used from the neighbor blocks. For all reference coefficients, 15 frequency models to predict signs of a given coefficient are used. All 7 probabilities (that the sign is negative) are mixed by logistic mixing. For test set of JPEG images, we show that the proposed method allows compressing signs of DCT coefficients by 1.1 ⋯ 1.3 times, significantly outperforming nearest analogues.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing, Kharkiv National Aerospace University
Contributors: Miroshnichenko, O., Ponomarenko, M., Lukin, V., Egiazarian, K.
Publication date: 2018

Host publication information

Title of host publication: Electronic Imaging : Image Processing: Algorithms and Systems XVI
Publisher: Society for Imaging Science and Technology
ASJC Scopus subject areas: Computer Graphics and Computer-Aided Design, Computer Science Applications, Human-Computer Interaction, Software, Electrical and Electronic Engineering, Atomic and Molecular Physics, and Optics
Keywords: Discrete cosine transform, JPEG, JPEG additional compression, Sign compression

Bibliographical note

jufoid=84313
EXT="Lukin, Vladimir"

Source: Scopus
Source ID: 85052859716

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

FS-PGBR: A scalable and delay sensitive cloud routing protocol

This paper proposes an improved version of a .fully tributed routing protocol, that is applicable for cloud computing infrastructure. Simulation results showstheprotocol is ideal for discovering cloud services ... a scalable manner with minimum latency.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Wireless Communications and Positioning (WICO), Waterford Institute of Technology, Telecommunications Software and Systems Group (TSSG), University of Helsinki
Contributors: Mineraud, J., Donnelly, W., Balasubramaniam, S., Kangasharju, J.
Number of pages: 2
Pages: 301-302
Publication date: 2012

Host publication information

Title of host publication: Proceedings of the ACM SIGCOMM 2012 and Best Papers of the Co-located Workshops
Volume: 42
Edition: 4
ISBN (Print): 9781450314190
ASJC Scopus subject areas: Computer Networks and Communications, Software
Keywords: Cloud computing infrastructure, Scalable route discovery
Source: Scopus
Source ID: 84894522377

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

The lord of the sense: A privacy preserving reputation system for participatory sensing applications

Electronic devices we use on a daily basis collect sensitive information without preserving user's privacy. In this paper, we propose the lord of the sense (LotS), a privacy preserving reputation system for participatory sensing applications. Our system maintains the privacy and anonymity of information with the use of cryptographic techniques and combines voting approaches to support users' reputation. Furthermore, LotS maintains accountability by tracing back a misbehaving user while maintaining k-anonymity. A detailed security analysis is presented with the current advantages and disadvantages of our system.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Security Lab, SICS, City University London
Contributors: Michalas, A., Komninos, N.
Publication date: 1 Jan 2014

Host publication information

Title of host publication: 2014 IEEE Symposium on Computers and Communications, ISCC 2014 - Proceedings
Publisher: Institute of Electrical and Electronics Engineers Inc.
Article number: 6912480
ISBN (Electronic): 9781479942787
ASJC Scopus subject areas: Software, Signal Processing, Mathematics(all), Computer Science Applications, Computer Networks and Communications
Keywords: Anonymity, Distributed Sensing, Participatory Sensing, Privacy, Reputation Systems, Security, Urban Sensing
Source: Scopus
Source ID: 84908199099

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

The Lord of the shares: Combining attribute-based encryption and searchable encryption for flexible data sharing

Secure cloud storage is considered one of the most important issues that both businesses and end-users are considering before moving their private data to the cloud. Lately, we have seen some interesting approaches that are based either on the promising concept of Symmetric Searchable Encryption (SSE) or on the well-studied field of Attribute-Based Encryption (ABE). In the first case, researchers are trying to design protocols where users' data will be protected from both internal and external attacks without paying the necessary attention to the problem of user revocation. On the other hand, in the second case existing approaches address the problem of revocation. However, the overall efficiency of these systems is compromised since the proposed protocols are solely based on ABE schemes and the size of the produced ciphertexts and the time required to decrypt grows with the complexity of the access formula. In this paper, we propose a protocol that combines both SSE and ABE in a way that the main advantages of each scheme are used. The proposed protocol allows users to directly search over encrypted data by using an SSE scheme while the corresponding symmetric key that is needed for the decryption is protected via a Ciphertext-Policy Attribute-Based Encryption scheme.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Computing Sciences
Contributors: Michalas, A.
Number of pages: 10
Pages: 146-155
Publication date: 2019

Host publication information

Title of host publication: Proceedings of the 34th ACM/SIGAPP Symposium on Applied Computing
Publisher: ACM
ISBN (Print): 9781450359337
ASJC Scopus subject areas: Software
Keywords: Access Control, Attribute-Based Encryption, Cloud Security, Hybrid Encryption, Policies, Storage Protection, Symmetric Searchable Encryption
Source: Scopus
Source ID: 85065666090

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Dominant Rotated Local Binary Patterns (DRLBP) for texture classification

In this paper, we present a novel rotation-invariant and computationally efficient texture descriptor called Dominant Rotated Local Binary Pattern (DRLBP). A rotation invariance is achieved by computing the descriptor with respect to a reference in a local neighborhood. A reference is fast to compute maintaining the computational simplicity of the Local Binary Patterns (LBP). The proposed approach not only retains the complete structural information extracted by LBP, but it also captures the complimentary information by utilizing the magnitude information, thereby achieving more discriminative power. For feature selection, we learn a dictionary of the most frequently occurring patterns from the training images, and discard redundant and non-informative features. To evaluate the performance we conduct experiments on three standard texture datasets: Outex12, Outex 10 and KTH-TIPS. The performance is compared with the state-of-the-art rotation invariant texture descriptors and results show that the proposed method is superior to other approaches.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Signal Processing, Research group: Computational Imaging-CI
Contributors: Mehta, R., Egiazarian, K.
Number of pages: 7
Pages: 16-22
Publication date: 2016
Peer-reviewed: Yes
Early online date: 30 Nov 2015

Publication information

Journal: Pattern Recognition Letters
Volume: 71
ISSN (Print): 0167-8655
Ratings: 
  • Scopus rating (2016): CiteScore 5.2 SJR 0.729 SNIP 1.678
Original language: English
ASJC Scopus subject areas: Software, Artificial Intelligence, Computer Vision and Pattern Recognition, Signal Processing
Keywords: Feature Selection, KTH-TIPS, Local Binary Pattern (LBP), Outex, Rotation Invariance, Texture Classification
Source: Scopus
Source ID: 84951106920

Research output: Contribution to journalArticleScientificpeer-review

Texture classification using dense micro-block difference

This paper is devoted to the problem of texture classification. Motivated by recent advancements in the field of compressive sensing and keypoints descriptors, a set of novel features called dense micro-block difference (DMD) is proposed. These features provide highly descriptive representation of image patches by densely capturing the granularities at multiple scales and orientations. Unlike most of the earlier work on local features, the DMD does not involve any quantization, thus retaining the complete information. We demonstrate that the DMD have dimensionality much lower than Scale Invariant Feature Transform (SIFT) and can be computed using integral image much faster than SIFT. The proposed features are encoded using the Fisher vector method to obtain an image descriptor, which considers high-order statistics. The proposed image representation is combined with the linear support vector machine classifier. Extensive experiments are conducted on five texture data sets (KTH-TIPS, UMD, KTH-TIPS-2a, Brodatz, and Curet) using standard protocols. The results demonstrate that our approach outperforms the state-of-the-art in texture classification.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Signal Processing, Research group: Computational Imaging-CI
Contributors: Mehta, R., Egiazarian, K.
Number of pages: 13
Pages: 1604-1616
Publication date: 1 Apr 2016
Peer-reviewed: Yes

Publication information

Journal: IEEE Transactions on Image Processing
Volume: 25
Issue number: 4
ISSN (Print): 1057-7149
Ratings: 
  • Scopus rating (2016): CiteScore 10.2 SJR 1.749 SNIP 3.397
Original language: English
ASJC Scopus subject areas: Computer Graphics and Computer-Aided Design, Software
Keywords: compressive sensing, descriptors, LBP, Scale Invariant Feature Transform, SVM, Texture classification
Source: Scopus
Source ID: 84963877958

Research output: Contribution to journalArticleScientificpeer-review

Special Issue on Embedded Computer Systems: Architectures, Modeling and Simulation

General information

Publication status: Published
MoE publication type: C2 Edited books
Organisations: Department of Pervasive Computing, University of Victoria, Canada, Department of Electrical and Computer Engineering,, Queen's University, Belfast, Northern Ireland, Leibniz-Universität Hannover, Queen’s University Belfast, University of Victoria
Contributors: McAllister, J., Guevorkian, D., Jeschke, H., Sima, M.
Publication date: 2014
Peer-reviewed: Yes

Publication information

Journal: International Journal of Parallel Programming
Volume: 43
Issue number: 1
ISSN (Print): 0885-7458
Ratings: 
  • Scopus rating (2014): CiteScore 1.5 SJR 0.256 SNIP 1.046
Original language: English
ASJC Scopus subject areas: Software, Information Systems, Theoretical Computer Science
Source: Scopus
Source ID: 84939892152

Research output: Contribution to journalSpecial issueScientificpeer-review

Mashing Up Software Issue Management, Development, and Usage Data

Modern software development approaches rely extensively on tools. Motivated by practices such as continuous integration, deployment and delivery, these tools are used in a fashion where data are automatically accumulated in different databases as a side-effect of everyday development activities. In this paper we introduce an approach for software engineering data visualization as a mash up that combines data from issue management, software development and production use. The visualization can show to all stake holders how well continuous delivery is realized in the project. The visualization clearly shows the time spent to specify and develop the features as well the length of the delivery cycle. Further more the visualization shows how much work is unfinished and waiting for delivery. This can help the development team to decrease the amount of unfinished work and by that help them to keep up in continuous delivery mind set. In addition to development data usage of the features is also visualized.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Pervasive Computing, Research area: Software engineering, Intelligent dexterity for secure networked infrastructure and applications (IDSNIA), Managing digital industrial transformation (mDIT), Solita Plc.
Contributors: Mattila, A., Lehtonen, T., Terho, H., Mikkonen, T., Systä, K.
Number of pages: 4
Pages: 26-29
Publication date: 24 Jul 2015

Host publication information

Title of host publication: 2015 IEEE/ACM 2nd International Workshop on Rapid Continuous Software Engineering (RCoSE)
Publisher: The Institute of Electrical and Electronics Engineers, Inc.
ISBN (Print): 9781479919345
ASJC Scopus subject areas: Software, Strategy and Management
Keywords: Continuous Delivery, Information Visualization, Software Analytics
Source: Scopus
Source ID: 84945956781

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Software visualization today - Systematic literature review

Software visualization means visualizing various aspects and artifacts related to software. By this definition a wide range of different software engineering aspects from program comprehension to understanding software process and usage are covered. This paper presents the results of systematic literature review spanning six years of software visualization literature. The main result shows that the most studied topics in the past six years are related to software structure, behavior and evolution. Software process and usage are addressed only in few studies. In the future studying the adoption of software visualization tools in industry context would be beneficial.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Department of Pervasive Computing, Research area: Software engineering, Research area: User experience
Contributors: Mattila, A., Ihantola, P., Kilamo, T., Luoto, A., Nurminen, M., Väätäjä, H.
Number of pages: 10
Pages: 262-271
Publication date: 17 Oct 2016

Host publication information

Title of host publication: AcademicMindtrek 2016 - Proceedings of the 20th International Academic Mindtrek Conference
Publisher: ACM
ISBN (Electronic): 9781450343671
ASJC Scopus subject areas: Human-Computer Interaction, Software, Computer Science Applications
Keywords: Human-centered computing, Software visualization, Systematic literature review
Source: Scopus
Source ID: 84994910745

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Continuous Edgewrite: Dictionary-based disambiguation instead of explicit segmentation by the user

Edgewrite is a text entry method where the user follows the edges of a physical guiding rectangle to enter corner sequences that are interpreted as characters. The original Edgewrite character set resembles the Latin alphabet and includes explicit character segmentation by lifting the stylus (or centering the joystick, etc). We present a variant of Edgewrite that we call the continuous Edgewrite. It relies on a dictionary instead of user's character segmentation to disambiguate words. New users can use the continuous Edgewrite with the help of an interactive visualization of possible continuations while writing. In a 6-session user study we measured initial text transcription performance (increased from 1 to 5.4 wpm) and the ratio of observed explicit segmentations to optimal continuous writing (decreased from 2.5 to 1.5). These results show that it is possible to learn to use the continuous writing mode, but also that the learning takes some time.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Augmented Human Activities (AHA), Université de Lorraine
Contributors: Martin, B., Isokoski, P., Karmann, G., Rollinger, T.
Number of pages: 8
Pages: 357-364
Publication date: 2012

Host publication information

Title of host publication: Proceedings of the Working Conference on Advanced Visual Interfaces, AVI 2012
ISBN (Print): 9781450312875
ASJC Scopus subject areas: Software, Human-Computer Interaction
Keywords: continuous writing, dictionary, disambiguation, EdgeWrite, segmentation, text entry
Source: Scopus
Source ID: 84863566610

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Fault tolerant control architecture design for mobile manipulation in scientific facilities

This paper describes one of the challenging issues implied by scientific infrastructures on a mobile robot cognition architecture. For a generally applicable cognition architecture, we study the dependencies and logical relations between several tasks and subsystems. The overall view of the software modules is described, including their relationship with a fault management module that monitors the consistency of the data flow among the modules. The fault management module is the solution of the deliberative architecture for the single point failures, and the safety anchor is the reactive solution for the faults by redundant equipment. In addition, a hardware architecture is proposed to ensure safe robot movement as a redundancy for the cognition of the robot. The method is designed for a four-wheel steerable (4WS) mobile manipulator (iMoro) as a case study.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Intelligent Hydraulics and Automation, Research group: Mobile manipulation, Research group: Field robotics and control, Field robotics for efficient work sites (FIRE)
Contributors: M. Aref, M., Oftadeh, R., Ghabcheloo, R., Mattila, J.
Publication date: 29 Jan 2015
Peer-reviewed: Yes

Publication information

Journal: international Journal of Advanced Robotic Systems
Volume: 12
Issue number: 4
ISSN (Print): 1729-8806
Ratings: 
  • Scopus rating (2015): CiteScore 2.1 SJR 0.346 SNIP 0.932
Original language: English
ASJC Scopus subject areas: Software, Artificial Intelligence, Computer Science Applications
Keywords: Architecture design, Autonomous vehicle drive, Cognition, Mobile robot, Remote handling
Source: Scopus
Source ID: 84923377541

Research output: Contribution to journalArticleScientificpeer-review

HCI and homecare: Connecting families and clinicians

The proposed workshop aims to form a community of individuals interested in using computing technology to promote healthcare and support wellness in the context of homecare. We strive to connect and engage researchers from several distinct fields of scientific inquiry and practice: people with clinical experience, developers of enabling technologies and HCI researchers interested in home healthcare and issues such as aging in place. The focus of this one-day workshop is on establishing common ground in vocabulary, research methods and research framework; understanding the shared needs of people with health challenges, their families and clinicians, and developing a joint framework for future research.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Visiting Graduate Student in Department of Urban Design and Planning, University of Washington, Seattle, USA 1.1.2012-15.6.2012 (12.9.2011 alkaen), VTT Technical Research Centre of Finland, Coherent, Inc., Aarhus Univ, Aarhus University, MINDLab, VTT Information Technology, Siemens Corporate Research, Center for Pervasive Healthcare, GVU Center, Georgia Institute of Technology, Information School and Biomedical and Health Informatics, University of Washington Seattle
Contributors: Mamykina, L., Bardram, J. E., Korhonen, I., Mynatt, E., Pratt, W.
Number of pages: 2
Pages: 1715-1716
Publication date: 2004

Host publication information

Title of host publication: Conference on Human Factors in Computing Systems - Proceedings
ISBN (Print): 1581137036, 9781581137033
ASJC Scopus subject areas: Human-Computer Interaction, Computer Graphics and Computer-Aided Design, Software
Keywords: Aging, Health care, Home, Medicine, Pervasive computing
Source: Scopus
Source ID: 84876764103

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Cultural influence on online community use: A cross-cultural study on online exercise diary users of three nationalities

This study investigates the influence of culture on the use of a website intended for tracking exercise activities. The data was collected using an online survey with 258 respondents from three national backgrounds: Germany, the USA and Spain. In the analysis, the focus was on determining whether users' cultural background impacts their use and perception of the site, especially as concerns social networking and the sharing of content. The Spanish were most interested in social networking, collaboration and sharing content with others, whereas the German participants were the least interested in these activities. The applicability of Hofstede's cultural theory in the explanation of differences between national cultures in online community use is discussed.

General information

Publication status: Published
MoE publication type: A1 Journal article-refereed
Organisations: Department of Pervasive Computing, University of Tampere
Contributors: Malinen, S., Nurkka, P.
Number of pages: 17
Pages: 153-169
Publication date: 2015
Peer-reviewed: Yes

Publication information

Journal: International Journal of Web Based Communities
Volume: 11
Issue number: 2
ISSN (Print): 1477-8394
Ratings: 
  • Scopus rating (2015): CiteScore 1.4 SJR 0.268 SNIP 0.406
Original language: English
ASJC Scopus subject areas: Computer Networks and Communications, Software, Education, Communication
Keywords: Cross-cultural research, Health and wellness applications, Online communities, SNSs, Social network sites

Bibliographical note

EXT="Malinen, Sanna"

Source: Scopus
Source ID: 84927129737

Research output: Contribution to journalArticleScientificpeer-review

Low-energy graph fourier basis functions span salient objects

There is an emerging interest aiming at defining principles for signals on general graphs, which are analogous to the basic principles in traditional signal processing. One example is the Graph Fourier Transform which aims at decomposing a graph signal into its components based on a set of basis functions with corresponding graph frequencies. It has been observed that most of the important information of a graph signal is contained inside the low frequency band, which leads to several applications such as denoising, compression, etc. In this paper, we show that the low frequency basis functions span the salient regions in an image, which can also be considered as important regions. Motivated by this, we present a novel simple and unsupervised method to utilize a number of low-energy basis functions and show that it improves the performance of seven state-of-the-art salient object detection methods in five datasets under four different evaluation criteria, with only minor exceptions.

General information

Publication status: Published
MoE publication type: A4 Article in a conference publication
Organisations: Signal Processing, Research group: Multimedia Research Group - MRG
Contributors: Malik, J., Aytekin, C., Gabbouj, M.
Number of pages: 5
Pages: 1548-1552
Publication date: 10 Sep 2018

Host publication information

Title of host publication: 2018 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2018 - Proceedings
Volume: 2018-April
Publisher: Institute of Electrical and Electronics Engineers Inc.
Article number: 8462672
ISBN (Print): 9781538646588
ASJC Scopus subject areas: Software, Signal Processing, Electrical and Electronic Engineering
Keywords: Graph fourier transform, Graph signal processing, Salient object detection

Bibliographical note

jufoid=57409

Source: Scopus
Source ID: 85054244934

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review