mdh.sePublications
Change search
Refine search result
1234567 1 - 50 of 1032
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Aarts, Marcel
    Mälardalen University, School of Innovation, Design and Engineering.
    Using Kinect to interact with presentation software2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Imagination Studios is a company specialized in motion capturing and animation. Part of their daily business is working at trade shows where they have a booth to keep close contact with existing customers and also to find new ones. However, usually only two to three people will be working at the booth, and frequently, these people will be in meetings with potential customers. During a time like this, nobody is free to attend to other people checking out the booth. This can result in a potential loss of a new customer. This project seeks a way to alleviate that problem.The idea behind this project was to create an application that trade show visitors can interact with in a playful and innovative way while also giving them a feel of what Imagination Studios is all about while looking for information about the company. To do this it was decided to let users interact with the system by using a Microsoft Kinect. The Kinect allows for easy implementation of a user interface based on motion capturing while also being very cost effective. A new user interface was to be designed as well, without copying already existing solutions and without simply expanding a traditional UI with new elements. To achieve this several design sketches were made, and the most interesting ones were then turned into storyboards. These were then used to decide on the final design, which was then elaborated on by use of video sketches and a collage in Adobe Photoshop.Several tools were used during the actual implementation. For the actual visualization and graphical design, the Unreal Engine 3 in combination with UDK was decided upon. To connect Kinect and Unreal Engine 3, a third party addon called NIUI which makes use of the open source SDK OpenNI was used. For ease of debugging and programming in Unrealscript, the programming language used by the Unreal Engine 3, an addon for Microsoft Visual Studio 2010 called nFringe (Pixel Mine, Inc., 2010) was used.

  • 2.
    Abbaspour Asadollah, Sara
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Daniel, Sundmark
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Eldh, S.
    Ericsson AB, Stockholm, Sweden.
    Hansson, Hans
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Concurrency bugs in open source software: a case study2017In: Journal of Internet Services and Applications, ISSN 1867-4828, Vol. 8, no 1, article id 4Article in journal (Refereed)
    Abstract [en]

    Concurrent programming puts demands on software debugging and testing, as concurrent software may exhibit problems not present in sequential software, e.g., deadlocks and race conditions. In aiming to increase efficiency and effectiveness of debugging and bug-fixing for concurrent software, a deep understanding of concurrency bugs, their frequency and fixing-times would be helpful. Similarly, to design effective tools and techniques for testing and debugging concurrent software, understanding the differences between non-concurrency and concurrency bugs in real-word software would be useful. This paper presents an empirical study focusing on understanding the differences and similarities between concurrency bugs and other bugs, as well as the differences among various concurrency bug types in terms of their severity and their fixing time, and reproducibility. Our basis is a comprehensive analysis of bug reports covering several generations of five open source software projects. The analysis involves a total of 11860 bug reports from the last decade, including 351 reports related to concurrency bugs. We found that concurrency bugs are different from other bugs in terms of their fixing time and severity while they are similar in terms of reproducibility. Our findings shed light on concurrency bugs and could thereby influence future design and development of concurrent software, their debugging and testing, as well as related tools.

  • 3.
    Abdullah, Syed Md Jakaria
    Mälardalen University, School of Innovation, Design and Engineering.
    Virtual Clustered-based Multiprocessor Scheduling in Linux Kernel2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Recent advancements of multiprocessor architectures have led to increasing use of multiprocessors in real-time embedded systems. The two most popular real-time scheduling approaches in multiprocessors are global and partitioned scheduling. Cluster based multiprocessor scheduling can be seen as a hybrid approach combining benefits of both partitioned and global scheduling. Virtual clustering further enhances it by providing dynamic cluster resource allocation duringrun-time and applying hierarchical scheduling to ensure temporal isolation between different software components. Over the years, the study of virtual clustered-based multiprocessor scheduling has been limited to theoretical analysis. In this thesis, we implemented a Virtual-Clustered Hierarchical Scheduling Framework (VC-HSF) in Linux without modifying the base Linux kernel. This work includes complete design, implementation and experimentation of this framework in a multiprocessor platform. Our main contributions are twofold: (i) to the best of our knowledge, our work is the first implementation of any virtual-clustered real-time multiprocessor scheduling in an operating system, (ii) our design and implementation gives practical insights about challenges of implementing any virtual-clustered algorithms for real-time scheduling.

  • 4.
    Abed Jaser, Zaid
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Al-Braichi, Osamah Haitham Sabhan
    Mälardalen University, School of Innovation, Design and Engineering.
    Measuring Test Coverage in Embedded Software Development Branches2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Most of the hardware products today, especially those that people interact with, are controlled by software. There are many devices with inbuilt software which many people do not bother to notice. Software may be critical in terms of strict quality requirements due to failures which enable risks of endangering the production and more importantly the lives of people. The testing team of Westermo Network Technologies AB faced a challenge with not being able to identify the coverage of tested cases in software. Identifying the coverage of total executed test cases enables the possibility of knowing the potential future quality of a software. By reaching such a stage a software will likely not suffer from failures due to higher quality, therefore the lives of people and the production at stake will not get harmed. The essential problem is that test cases are both tested and skipped, which makes it more difficult for the company to identify what has been actually tested and skipped. The purpose of this thesis is to identify and calculate the coverage of test cases, the process was mainly to understand the essence in the identification of executed test cases. The ethical aspect of putting people's lives at stake is what inspired us to investigate software failures. Software is typically tested before a release, therefore our investigation was to research testing process of software. When investigating test result over many days and test systems we developed a coverage calculator system which helps Westermo to decide and determine the release of tested software, either the software test result is acceptable for a release or not.

  • 5.
    Abedini, M.
    et al.
    Department of Industrial Engineering, Iran University of Science and Technology, Tehran, Iran.
    Ahmadzadeh, Farzaneh
    Mälardalen University, School of Innovation, Design and Engineering, Innovation and Product Realisation.
    Noorossana, R.
    Department of Industrial Engineering, Iran University of Science and Technology, Tehran, Iran.
    Customer credit scoring using a hybrid data mining approach2016In: Kybernetes, ISSN 0368-492X, E-ISSN 1758-7883, Vol. 45, no 10, p. 1576-1588Article in journal (Refereed)
    Abstract [en]

    Purpose: A crucial decision in financial services is how to classify credit or loan applicants into good and bad applicants. The purpose of this paper is to propose a four-stage hybrid data mining approach to support the decision-making process. Design/methodology/approach: The approach is inspired by the bagging ensemble learning method and proposes a new voting method, namely two-level majority voting in the last stage. First some training subsets are generated. Then some different base classifiers are tuned and afterward some ensemble methods are applied to strengthen tuned classifiers. Finally, two-level majority voting schemes help the approach to achieve more accuracy. Findings: A comparison of results shows the proposed model outperforms powerful single classifiers such as multilayer perceptron (MLP), support vector machine, logistic regression (LR). In addition, it is more accurate than ensemble learning methods such as bagging-LR or rotation forest (RF)-MLP. The model outperforms single classifiers in terms of type I and II errors; it is close to some ensemble approaches such as bagging-LR and RF-MLP but fails to outperform them in terms of type I and II errors. Moreover, majority voting in the final stage provides more reliable results. Practical implications: The study concludes the approach would be beneficial for banks, credit card companies and other credit provider organisations. Originality/value: A novel four stages hybrid approach inspired by bagging ensemble method proposed. Moreover the two-level majority voting in two different schemes in the last stage provides more accuracy. An integrated evaluation criterion for classification errors provides an enhanced insight for error comparisons.

  • 6.
    Abelli, Björn
    Mälardalen University, School of Business.
    Directing and Enacting the Information System2007In: Advances in Information Systems Development: New Methods and Practice for the Networked Society, Volume 2, Issue PART 2, 2007, p. 13-23Conference paper (Refereed)
  • 7.
    Abelli, Björn
    Mälardalen University, School of Business.
    Enacting the e-Society2006In: Proceedings of the IADIS International Conference e-Society 2006, 2006, p. 285-298Conference paper (Refereed)
  • 8.
    Abelli, Björn
    Mälardalen University, School of Business.
    Programmeringens grunder - med exempel i C#2004Book (Other (popular science, discussion, etc.))
    Abstract [en]

    Detta är en lärobok i grundläggande programmering. Den fokuserar på att lära ut det som är gemensamt för de flesta programmeringsspråk – de grundläggande elementen och programkonstruktionerna och hur dessa relaterar till varandra, oberoende av språket. Vilket språk programmet skrivs i måste vara underordnat den uppgift programmet skall lösa. Boken går därför igenom grunderna i strukturerad programmering och visar otaliga exempel i såväl flödesdiagram, strukturdiagram, pseudokod som i källkod. I slutet av boken finns kapitel som går igenom grunderna även i objektorienterad programmering.

    Boken tonar ner inlärningen av ett specifikt programmeringsspråk, men i slutändan måste program ändå skrivas i något språk. Exemplen är skrivna i C# som har slagit igenom som ett praktiskt programmeringsspråk på mycket kort tid och redan börjat göra sitt intåg i högskolekurser i programmering.

    I första hand är boken avsedd för nybörjare i programmering på högskolenivå, som vill lära sig programmeringens grunder.

  • 9.
    Abelli, Björn
    et al.
    Mälardalen University, School of Business.
    Révay, Péter
    Mälardalen University, School of Business.
    To Be or Not To Be Computer Based2004In: Proceedings of microCAD 2004, 2004, p. 1-8Conference paper (Refereed)
  • 10.
    Abrahamsson, Henrik
    Mälardalen University, School of Innovation, Design and Engineering.
    Internet Traffic Management2008Licentiate thesis, comprehensive summary (Other scientific)
  • 11.
    Abrahamsson, Henrik
    Mälardalen University, School of Innovation, Design and Engineering.
    Network overload avoidance by traffic engineering and content caching2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The Internet traffic volume continues to grow at a great rate, now driven by video and TV distribution. For network operators it is important to avoid congestion in the network, and to meet service level agreements with their customers.  This thesis presents work on two methods operators can use to reduce links loads in their networks: traffic engineering and content caching.

    This thesis studies access patterns for TV and video and the potential for caching.  The investigation is done both using simulation and by analysis of logs from a large TV-on-Demand system over four months.

    The results show that there is a small set of programs that account for a large fraction of the requests and that a comparatively small local cache can be used to significantly reduce the peak link loads during prime time. The investigation also demonstrates how the popularity of programs changes over time and shows that the access pattern in a TV-on-Demand system very much depends on the content type.

    For traffic engineering the objective is to avoid congestion in the network and to make better use of available resources by adapting the routing to the current traffic situation. The main challenge for traffic engineering in IP networks is to cope with the dynamics of Internet traffic demands.

    This thesis proposes L-balanced routings that route the traffic on the shortest paths possible but make sure that no link is utilised to more than a given level L. L-balanced routing gives efficient routing of traffic and controlled spare capacity to handle unpredictable changes in traffic.  We present an L-balanced routing algorithm and a heuristic search method for finding L-balanced weight settings for the legacy routing protocols OSPF and IS-IS. We show that the search and the resulting weight settings work well in real network scenarios.

  • 12.
    Abrahamsson, Henrik
    et al.
    Swedish Institute of Computer Science, Kista, Sweden.
    Björkman, Mats
    Mälardalen University, School of Innovation, Design and Engineering.
    Caching for IPTV distribution with time-shift2013In: 2013 International Conference on Computing, Networking and Communications, ICNC 2013, IEEE , 2013, p. 916-921Conference paper (Refereed)
    Abstract [en]

    Today video and TV distribution dominate Internet traffic and the increasing demand for high-bandwidth multimedia services puts pressure on Internet service providers. In this paper we simulate TV distribution with time-shift and investigate the effect of introducing a local cache close to the viewers. We study what impact TV program popularity, program set size, cache replacement policy and other factors have on the caching efficiency. The simulation results show that introducing a local cache close to the viewers significantly reduces the network load from TV-on-Demand services. By caching 4% of the program volume we can decrease the peak load during prime time by almost 50%. We also show that the TV program type and how program popularity changes over time can have a big influence on cache hit ratios and the resulting link loads

  • 13.
    Abrahamsson, Henrik
    et al.
    Swedish Institute of Computer Science.
    Björkman, Mats
    Mälardalen University, School of Innovation, Design and Engineering.
    Simulation of IPTV caching strategies2010In: Proceedings of the 2010 International Symposium on Performance Evaluation of Computer and Telecommunication Systems, 2010, p. 187-193Conference paper (Refereed)
    Abstract [en]

    IPTV, where television is distributed over the Internet Protocol in a single operator network, has become popular and widespread. Many telecom and broadband companies have become TV providers and distribute TV channels using multicast over their backbone networks. IPTV also means an evolution to time-shifted television where viewers now often can choose to watch the programs at any time. However, distributing individual TV streams to each viewer requires a lot of bandwidth and is a big challenge for TV operators. In this paper we present an empirical IPTV workload model, simulate IPTV distribution with time-shift, and show that local caching can limit the bandwidth requirements significantly.

  • 14.
    Abrahamsson, Henrik
    et al.
    Swedish Institute of Computer Science, Kista, Sweden.
    Nordmark, Mattias
    TeliaSonera AB, Stockholm, Sweden .
    Program popularity and viewer behaviour in a large TV-on-Demand system2012In: IMC '12 Proceedings of the 2012 ACM conference on Internet measurement conference, New York: ACM , 2012, p. 199-210Conference paper (Refereed)
    Abstract [en]

    Today increasingly large volumes of TV and video are distributed over IP-networks and over the Internet. It is therefore essential for traffic and cache management to understand TV program popularity and access patterns in real networks.

    In this paper we study access patterns in a large TV-on-Demand system over four months. We study user behaviour and program popularity and its impact on caching. The demand varies a lot in daily and weekly cycles. There are large peaks in demand, especially on Friday and Saturday evenings, that need to be handled.

    We see that the cacheability, the share of requests that are not first-time requests, is very high. Furthermore, there is a small set of programs that account for a large fraction of the requests. We also find that the share of requests for the top most popular programs grows during prime time, and the change rate among them decreases. This is important for caching. The cache hit ratio increases during prime time when the demand is the highest, and aching makes the biggest difference when it matters most.

    We also study the popularity (in terms of number of requests and rank) of individual programs and how that changes over time. Also, we see that the type of programs offered determines what the access pattern will look like.

  • 15.
    Achrenius, William
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Bergman Törnkvist, Martin
    Mälardalen University, School of Innovation, Design and Engineering.
    GRAPH GENERATION ALGORITHMS FOR THE GRADE DECISION CANVAS2018Independent thesis Basic level (degree of Bachelor), 12 HE creditsStudent thesis
    Abstract [en]

    Development in the field of software architecture, from the early days in the mid-80’s, has been significant. From purely technical descriptions to decision based architectural knowledge, software architecture has seen fundamental changes to its methodologies and techniques. Architectural knowledge is a resource that is managed and stored by companies, this resource is valuable because it can be reused and analysed to improve future development. Companies today are interested in the reasoning behind the software architecture. This reasoning is mainly formulated through the architectural decisions made during development. For architectural decisions to be easier to analyse they need to be stored in a way that enables use of common analytical tools so that comparisons between decisions are consistent and relevant. Additionally, it is also important to have enough data, which leads us to the problem that, preferably, all the individual architectural knowledge cases must be structured and stored. To do this we present a tool that uses graph generation algorithms to generate architectural knowledge as graphs based on an architectural decision canvas called GRADE. This enables multiple decision cases to be encoded through graphs that can be used to analyse relationships and balances between different architectural knowledge elements represented through nodes and edges within a graph.

  • 16.
    Achuthan, Krishnashree
    et al.
    Amrita Vishwa Vidyapeetham, Amrita Ctr Cybersecur Syst & Networks, Kollam, Kerala, India..
    Ramesh, Maneesha V.
    Amrita Vishwa Vidyapeetham, Amrita Ctr Int Programs, Kollam, Kerala, India..
    Punnekkat, Sasikumar
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Raman, Raghu
    Amrita Vishwa Vidyapeetham, Ctr Res Adv Technol Educ, Kollam, Kerala, India..
    Internationalizing Engineering Education With Phased Study Programs: India-European Experience2014In: 2014 IEEE FRONTIERS IN EDUCATION CONFERENCE (FIE), IEEE , 2014, p. 295-301Conference paper (Refereed)
    Abstract [en]

    Most of the critical challenges seen in the past decades have impacted citizens in a global way. Given shrinking resources, educationists find preparing students for the global market place a formidable challenge. Hence exposing students to multi-lateral educational initiatives are critical to their growth, understanding and future contributions. This paper focuses on European Union's Erasmus Mundus programs, involving academic cooperation amongst international universities in engineering programs. A phased undergraduate engineering program with multiple specializations is analyzed within this context. Based on their performance at the end of first phase, selected students were provided opportunities using scholarship to pursue completion of their degree requirements at various European universities. This paper will elaborate the impact of differing pedagogical interventions, language and cultural differences amongst these countries on students in diverse engineering disciplines. The data presented is based on on the feedback analysis from Eramus Mundus students (N = 121) that underwent the mobility programs. The findings have given important insights into the structure of the initiative and implications for academia and education policy makers for internationalizing engineering education. These included considering digital interventions such as MOOCs (Massive Open Online Courses) and Virtual Laboratory (VL) initiatives for systemic reorganization of engineering education.

  • 17.
    Afshar, Sara
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Lock-Based Resource Sharing in Real-Time Multiprocessor Platforms2014Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Embedded systems are typically resource constrained, i.e., resources such as processors, I/O devices, shared buffers or shared memory can be limited for tasks in the system. Therefore, techniques that enable an efficient usage of such resources are of great importance.

    In the industry, typically large and complex software systems are divided into smaller parts (applications) where each part is developed independently. Migration towards multiprocessor platforms has become inevitable from an industrial perspective. Due to such migration and to efficient use of system resources, these applications eventually may be integrated on a shared multiprocessor platform. In order to facilitate the integration phase of the applications on a shared platform, the timing and resource requirements of each application can be provided in an interface when the application is developed. The system integrator can benefit from such provided information in the interface of each application to ease the integration process. In this thesis, we have provided the resource and timing requirements of each application in their interfaces for applications that may need several processors to be allocated on when they are developed.

    Although many scheduling techniques have been studied for multiprocessor systems, these techniques are usually based on the assumption that tasks are independent, i.e. do not share resources other than the processors. This assumption is typically not true. In this thesis, we provide an extension to such systems to handle sharing of resources other than processor among tasks. Two traditional approaches exist for multiprocessor systems to schedule tasks on processors. A recent scheduling approach for multiprocessors has combined the two traditional approaches and achieved a hybrid more efficient approach compared to the two previous one. Due to the complex nature of this scheduling approach the conventional approaches for resource sharing could not be used straight forwardly. In this thesis, we have modified resource sharing approaches such that they can be used in such hybrid scheduling systems. A second concern is that enabling resource sharing in the systems can cause unpredictable delays and variations in response time of tasks which can degrade system performance. Therefore, it is of great significance to improve the resource handling techniques to reduce the effect of imposed delays caused by resource sharing in a multiprocessor platform. In this thesis we have proposed alternative techniques for resource handling that can improve system performance for special setups.

  • 18.
    Afshar, Sara
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Behnam, Moris
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Bril, R. J.
    Technische Universiteit Eindhoven, Eindhoven, Netherlands .
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Flexible spin-lock model for resource sharing in multiprocessor real-time systems2014In: Proc. IEEE Int. Symp. Ind. Embedded Syst., SIES, 2014, p. 41-51Conference paper (Refereed)
    Abstract [en]

    Various approaches can be utilized upon resource locking for mutually exclusive resource access in multiprocessor platforms. So far two conventional approaches exist for dealing with tasks that are blocked on a global resource in a multi-processor platform. Either the blocked task performs a busy wait, i.e. spins, at the highest priority level until the resource is released, or it is suspended. Although both approaches provide mutually exclusive access to resources, they can introduce long blocking delays to tasks, which may be unacceptable for many industrial applications. In this paper, we propose a general spin-based model for resource sharing in multiprocessor platforms in which the priority of the blocked tasks during spinning can be selected arbitrarily. Moreover, we provide the analysis for two selected spin-lock priorities and we show by means of a general comparison as well as specific examples that these solutions may provide a better performance for higher priority tasks.

  • 19.
    Afshar, Sara
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Behnam, Moris
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Bril, Reinder J.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. Technische Universiteit Eindhoven, Eindhoven, Netherlands.
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Resource Sharing Under Global Scheduling with Partial Processor Bandwidth2015In: 2015 10th IEEE International Symposium on Industrial Embedded Systems, SIES 2015 - Proceedings, 2015, p. 195-206Conference paper (Refereed)
    Abstract [en]

    Resource efficient approaches are of great importance for resource constrained embedded systems. In this paper, we present an approach targeting systems where tasks of a critical application are partitioned on a multi-core platform and by using resource reservation techniques, the remaining bandwidth capacity on each core is utilized for one or a set of non-critical application(s). To provide a resource efficient solution and to exploit the potential parallelism of the extra applications on the multi-core processor, global scheduling is used to schedule the tasks of the non-critical applications. Recently a specific instantiation of such a system has been studied where tasks do not share resources other than the processor. In this paper, we enable semaphore-based resource sharing among tasks within critical and non-critical applications using a suspension-based synchronization protocol. Tasks of non-critical applications have partial access to the processor bandwidth. The paper provides the systems schedulability analysis where blocking due to resource sharing is bounded. Further, we perform experimental evaluations under balanced and unbalanced allocation of tasks of a critical application to cores.

  • 20.
    Afshar, Sara
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Behnam, Moris
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    J. Bril, Reinder
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Per Processor Spin-Lock Priority for Partitioned Multiprocessor Real-Time Systems2014Report (Other academic)
    Abstract [en]

    Two traditional approaches exist for a task that is blocked on a global resource; a task either performs a non-preemptive busy wait, i.e., spins, or suspends and releases the processor. Previously, we have shown that both approaches can be viewed as spinning either at the highest priority HP or at the lowest priority on the processor LP, respectively. Based on this view, previously we have generalized a task's blocking behavioral model, as spinning at any arbitrary priority level. In this paper, we focus on a particular class of spin-lock protocols from the introduced flexible spin-lock model where spinning is performed at a priority equal to or higher than the highest local ceiling of the global resources accessed on a processor referred to as CP spin-lock approach. In this paper, we assume that all tasks of a specific processor are spinning on the same priority level. Given this class and assumption, we show that there exists a spin-lock protocol in this range that dominates the classic spin-lock protocol which tasks spin on highest priority level (HP). However we show that this new approach is incomparable with the CP spin-lock approach. Moreover, we show that there may exist an intermediate spin-lock approach between the priority used by CP spin-lock approach and the new introduced spin-lock approach that can make a task set schedulable when those two cannot. We provide an extensive evaluation results comparing the HP, CP and the new proposed approach.

  • 21.
    Afshar, Sara
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Behnam, Moris
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    J. Bril, Reinder
    Technische Universiteit Eindhoven, Eindhoven, The Netherlands.
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Per Processor Spin-Lock Priority for Partitioned Multiprocessor Real-Time Systems2017In: Leibniz Transactions on Embedded Systems, ISSN 2199-2002, no 2Article in journal (Other academic)
    Abstract [en]

    Two traditional approaches exist for a task that is blocked on a global resource; a task either performs a non-preemptive busy wait, i.e., spins, or suspends and releases the processor. Previously, we have shown that both approaches can be viewed as spinning either at the highest priority HP or at the lowest priority on the processor LP, respectively. Based on this view, previously we have generalized a task's blocking behavioral model, as spinning at any arbitrary priority level. In this paper, we focus on a particular class of spin-lock protocols from the introduced flexible spin-lock model where spinning is performed at a priority equal to or higher than the highest local ceiling of the global resources accessed on a processor referred to as CP spin-lock approach. In this paper, we assume that all tasks of a specific processor are spinning on the same priority level. Given this class and assumption, we show that there exists a spin-lock protocol in this range that dominates the classic spin-lock protocol which tasks spin on highest priority level (HP). However we show that this new approach is incomparable with the CP spin-lock approach. Moreover, we show that there may exist an intermediate spin-lock approach between the priority used by CP spin-lock approach and the new introduced spin-lock approach that can make a task set schedulable when those two cannot. We provide an extensive evaluation results comparing the HP, CP and the new proposed approach.

  • 22.
    Afzal, Wasif
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Bruneliere, H.
    IMT Atlantique – LS2N (CNRS) – ARMINES, France.
    Di Ruscio, D.
    Università degli Studi dell'Aquila - DISIM | Center of Excellence DEWS, Italy.
    Sadovykh, A.
    Softeam, France.
    Mazzini, S.
    Intecs, Italy.
    Cariou, E.
    Université de Pau et des Pays de l'Adour, LIUPPA, France.
    Truscan, D.
    Åbo Akademi University, Finland.
    Cabot, J.
    ICREA, Spain.
    Gómez, A.
    Internet Interdisciplinary Institute (IN3), Universitat Oberta de Catalunya (UOC), Spain.
    Gorroñogoitia, J.
    ATOS, Spain.
    Pomante, L.
    Università degli Studi dell'Aquila - DISIM | Center of Excellence DEWS, Italy.
    Smrz, P.
    Brno University of Technology, Czech Republic.
    The MegaM@Rt2 ECSEL project: MegaModelling at Runtime – Scalable model-based framework for continuous development and runtime validation of complex systems2018In: Microprocessors and microsystems, ISSN 0141-9331, E-ISSN 1872-9436, Vol. 61, p. 86-95Article in journal (Refereed)
    Abstract [en]

    A major challenge for the European electronic industry is to enhance productivity by ensuring quality of development, integration and maintenance while reducing the associated costs. Model-Driven Engineering (MDE) principles and techniques have already shown promising capabilities, but they still need to scale up to support real-world scenarios implied by the full deployment and use of complex electronic components and systems. Moreover, maintaining efficient traceability, integration, and communication between two fundamental system life cycle phases (design time and runtime) is another challenge requiring the scalability of MDE. This paper presents an overview of the ECSEL 1 project entitled “MegaModelling at runtime – Scalable model-based framework for continuous development and runtime validation of complex systems” (MegaM@Rt2), whose aim is to address the above mentioned challenges facing MDE. Driven by both large and small industrial enterprises, with the support of research partners and technology providers, MegaM@Rt2 aims to deliver a framework of tools and methods for: 1) system engineering/design and continuous development, 2) related runtime analysis and 3) global models and traceability management. Diverse industrial use cases (covering strategic domains such as aeronautics, railway, construction and telecommunications) will integrate and demonstrate the validity of the MegaM@Rt2 solution. This paper provides an overview of the MegaM@Rt2 project with respect to its approach, mission, objectives as well as to its implementation details. It further introduces the consortium as well as describes the work packages and few already produced deliverables.

  • 23.
    Afzal, Wasif
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Caporuscio, M.
    Linnaeus University, Sweden.
    Conboy, H.
    University of Massachusetts Amherst, MA, United States.
    Di Marco, A.
    University of l'Aquila, Italy.
    Duchien, D. L.
    University of Lille, France.
    Pérez, D.
    University of British Columbia, Canada.
    Seceleanu, C.
    Kyushu University, Japan.
    Shahbazian, A.
    University of California, Berkeley, CA, United States.
    Spalazzese, R.
    Microsoft, WA, United States.
    Tivoli, M.
    Florida State University, FL, United States.
    Vasilescu, B.
    University College Dublin and Lero, Ireland.
    Washizaki, H
    Mälardalen University.
    Weyns, D.
    University of Southern California, CA, United States.
    Pasquale, L.
    Malmö University, Sweden.
    Nistor, A.
    Malmö University, Sweden.
    Muşlu, K.
    Waseda University, Japan.
    Kamei, Y.
    Waseda University, Japan.
    Hanam, Q.
    Carnegie Mellon University, PA, United States.
    Ying, A. T. T.
    Katholieke Universiteit Leuven, Belgium.
    Program committee for icse 2018 posters track2018In: Proceedings / International Conference of Software Engineering, ISSN 0270-5257, E-ISSN 1558-1225, Vol. Part F137351Article in journal (Refereed)
  • 24.
    Afzal, Wasif
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Ghazi, Nauman
    Blekinge Institute of Technolog.
    Itkonen, Juha
    Aalto University, Espoo, Finland.
    Torkar, Richard
    Chalmers University of Technology.
    Andrews, Anneliese
    University of Denver, USA.
    Bhatti, Khurram
    Blekinge Institute of Technolog.
    An experiment on the effectiveness and efficiency of exploratory testing2015In: Journal of Empirical Software Engineering, ISSN 1382-3256, E-ISSN 1573-7616, Vol. 20, no 3, p. 844-878Article in journal (Refereed)
    Abstract [en]

    The exploratory testing (ET) approach is commonly applied in industry, but lacks scientific research. The scientific community needs quantitative results on the performance of ET taken from realistic experimental settings. The objective of this paper is to quantify the effectiveness and efficiency of ET vs. testing with documented test cases (test case based testing, TCT). We performed four controlled experiments where a total of 24 practitioners and 46 students performed manual functional testing using ET and TCT. We measured the number of identified defects in the 90-minute testing sessions, the detection difficulty, severity and types of the detected defects, and the number of false defect reports. The results show that ET found a significantly greater number of defects. ET also found significantly more defects of varying levels of difficulty, types and severity levels. However, the two testing approaches did not differ significantly in terms of the number of false defect reports submitted. We conclude that ET was more efficient than TCT in our experiment. ET was also more effective than TCT when detection difficulty, type of defects and severity levels are considered. The two approaches are comparable when it comes to the number of false defect reports submitted.

  • 25.
    Afzal, Wasif
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. Bahria University, Islamabad, Pakistan .
    Torkar, Richard
    Blekinge Institute of Technology, Karlskrona, Sweden; Chalmers University of Technology, Sweden.
    Towards benchmarking feature subset selection methods for software fault prediction2016In: Computational Intelligence and Quantitative Software Engineering / [ed] Witold Pedrycz, Giancarlo Succi and Alberto Sillitti, Springer-Verlag , 2016, p. 33-58Chapter in book (Other academic)
    Abstract [en]

    Despite the general acceptance that software engineering datasets often contain noisy, irrele- vant or redundant variables, very few benchmark studies of feature subset selection (FSS) methods on real-life data from software projects have been conducted. This paper provides an empirical comparison of state-of-the-art FSS methods: information gain attribute ranking (IG); Relief (RLF); principal com- ponent analysis (PCA); correlation-based feature selection (CFS); consistency-based subset evaluation (CNS); wrapper subset evaluation (WRP); and an evolutionary computation method, genetic program- ming (GP), on five fault prediction datasets from the PROMISE data repository. For all the datasets, the area under the receiver operating characteristic curve—the AUC value averaged over 10-fold cross- validation runs—was calculated for each FSS method-dataset combination before and after FSS. Two diverse learning algorithms, C4.5 and na ??ve Bayes (NB) are used to test the attribute sets given by each FSS method. The results show that although there are no statistically significant differences between the AUC values for the different FSS methods for both C4.5 and NB, a smaller set of FSS methods (IG, RLF, GP) consistently select fewer attributes without degrading classification accuracy. We conclude that in general, FSS is beneficial as it helps improve classification accuracy of NB and C4.5. There is no single best FSS method for all datasets but IG, RLF and GP consistently select fewer attributes without degrading classification accuracy within statistically significant boundaries.

  • 26.
    Agbamuche, Joy
    Mälardalen University, School of Sustainable Development of Society and Technology.
    How does the alignment of IT to business strategy affect the organisation of the IT function?2008Student thesis
    Abstract [en]

    Date: 2008-06-04

    Purpose: The primary goal of this research is to describe the IT function and examine how its alignment to an organisations strategy affects the way it is organised.

    Method: The chosen method was a purely theoretical examination with the use of the case study of Windham International as primary resource and secondary resources such as book and literature review used for the thesis.

    Research Questions: How does the alignment of IT to business strategy affect the organisation of the IT function?

    Conclusion: One of the findings was that a few researchers seem to suggest that the centralized mode of organising IT was symbolic of the past, while outsourcing and decentralization are the modern approach to organising IT. Wyndham International shows the opposite, after the introduction of the CIO in 2002, centralization was the chosen mode of organisation because that was what would best fit the new strategic approach of the organisation. Insourcing rather than outsourcing proved to be a winning formula.

  • 27.
    Ahlberg, Carl
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Embedded high-resolution stereo-vision of high frame-rate and low latency through FPGA-acceleration2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Autonomous agents rely on information from the surrounding environment to act upon. In the array of sensors available, the image sensor is perhaps the most versatile, allowing for detection of colour, size, shape, and depth. For the latter, in a dynamic environment, assuming no a priori knowledge, stereo vision is a commonly adopted technique. How to interpret images, and extract relevant information, is referred to as computer vision. Computer vision, and specifically stereo-vision algorithms, are complex and computationally expensive, already considering a single stereo pair, with results that are, in terms of accuracy, qualitatively difficult to compare. Adding to the challenge is a continuous stream of images, of a high frame rate, and the race of ever increasing image resolutions. In the context of autonomous agents, considerations regarding real-time requirements, embedded/resource limited processing platforms, power consumption, and physical size, further add up to an unarguably challenging problem.

    This thesis aims to achieve embedded high-resolution stereo-vision of high frame-rate and low latency, by approaching the problem from two different angles, hardware and algorithmic development, in a symbiotic relationship. The first contributions of the thesis are the GIMME and GIMME2 embedded vision platforms, which offer hardware accelerated processing through FGPAs, specifically targeting stereo vision, contrary to available COTS systems at the time. The second contribution, toward stereo vision algorithms, is twofold. Firstly, the problem of scalability and the associated disparity range is addressed by proposing a segment-based stereo algorithm. In segment space, matching is independent of image scale, and similarly, disparity range is measured in terms of segments, indicating relatively few hypotheses to cover the entire range of the scene. Secondly, more in line with the conventional stereo correspondence for FPGAs, the Census Transform (CT) has been identified as a recurring cost metric. This thesis proposes an optimisation of the CT through a Genetic Algorithm (GA) - the Genetic Algorithm Census Transform (GACT). The GACT shows promising results for benchmark datasets, compared to established CT methods, while being resource efficient.

  • 28.
    Ahlberg, Carl
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Leon, Miguel
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Ekstrand, Fredrik
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Ekström, Mikael
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Unbounded Sparse Census Transform using Genetic Algorithm2019In: 2019 IEEE WINTER CONFERENCE ON APPLICATIONS OF COMPUTER VISION (WACV), IEEE , 2019, p. 1616-1625Conference paper (Refereed)
    Abstract [en]

    The Census Transform (CT) is a well proven method for stereo vision that provides robust matching, with respect to object boundaries, outliers and radiometric distortion, at a low computational cost. Recent CT methods propose patterns for pixel comparison and sparsity, to increase matching accuracy and reduce resource requirements. However, these methods are bounded with respect to symmetry and/or edge length. In this paper, a Genetic algorithm (GA) is applied to find a new and powerful CT method. The proposed method, Genetic Algorithm Census Transform (GACT), is compared with the established CT methods, showing better results for benchmarking datasets. Additional experiments have been performed to study the search space and the correlation between training and evaluation data.

  • 29.
    Ahlström, Louise
    Mälardalen University, School of Innovation, Design and Engineering.
    Informationsmaterial till Europaskolan2008Student thesis
    Abstract [sv]

    Rapporten är resultatet av mitt examensarbete i Textdesign vid Mälardalens högskola. På uppdrag av Europaskolan i Strängnäs har ett informationsmaterial utvecklats och resulterat i en broschyr. Målgruppen är elever i årskurs nio som ska söka gymnasieutbildning. Rapporten beskriver det tillvägagångssätt som använts vid

    framtagningen av det nya informationsmaterialet. Med utgångspunkt i begreppen läsligt, läsbart och läsvärt har text, bild och layout utformats för att skapa en informativ och målgruppsanpassad broschyr. Metoder som använts är komparation, textanalys och litteraturstudier. Utprovningsmetoden som tillämpats är enskilda intervjuer med elever

    på Europaskolan. Slutsatser som dragits är att behovet av designad information ökar i dagens mediebrus och att sändarens budskap till mottagaren måste genomgå en hermeneutisk process.

  • 30.
    Ahmadi, Dara
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Panin, Vadim
    Mälardalen University, School of Innovation, Design and Engineering.
    Skissamarbete på digitala plattformar2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Computer-Supported Cooperative Work (CSCW) relates to working in group by distance using computer-based systems and aims to achieve the optimal efficiency in the group's working process. Such systems include computersupported collaborative sketching system. In interaction design, there is an interest in sketch collaboration on digital systems. We have therefore chosen, within the frame of this work, to investigate whether collaborative sketching using digital platform applications lead to an effective way of working for designers and what functionalities such applications should include. To get answers to our questions, we have chosen to create an Android as well as a Web application for sketch collaboration. In our applications we have considered the designers' wishes regarding functionalities. The applications were used in a research to be able to analyze how designers collaborate on digital platforms. Our results have proven that collaborative sketching on digital platforms is a smooth and mobile way of working which involves active discussions, creating new ideas and better solutions, contributes to knowledge transfer and a better working environment and interaction between designers.

  • 31.
    Ahmed, Mobyen Uddin
    Mälardalen University, School of Innovation, Design and Engineering.
    A case-based multi-modal clinical system for stress management2010Licentiate thesis, monograph (Other academic)
    Abstract [en]

    A difficult issue in stress management is to use biomedical sensor signal in the diagnosis and treatment of stress. Clinicians often make their diagnosis and decision based on manual inspection of physiological signals such as, ECG, heart rate, finger temperature etc. However, the complexity associated with manual analysis and interpretation of the signals makes it difficult even for experienced clinicians. Today the diagnosis and decision is largely dependent on how experienced the clinician is interpreting the measurements.  A computer-aided decision support system for diagnosis and treatment of stress would enable a more objective and consistent diagnosis and decisions.

    A challenge in the field of medicine is the accuracy of the system, it is essential that the clinician is able to judge the accuracy of the suggested solutions. Case-based reasoning systems for medical applications are increasingly multi-purpose and multi-modal, using a variety of different methods and techniques to meet the challenges of the medical domain. This research work covers the development of an intelligent clinical decision support system for diagnosis, classification and treatment in stress management. The system uses a finger temperature sensor and the variation in the finger temperature is one of the key features in the system. Several artificial intelligence techniques have been investigated to enable a more reliable and efficient diagnosis and treatment of stress such as case-based reasoning, textual information retrieval, rule-based reasoning, and fuzzy logic. Functionalities and the performance of the system have been validated by implementing a research prototype based on close collaboration with an expert in stress. The case base of the implemented system has been initiated with 53 reference cases classified by an experienced clinician. A case study also shows that the system provides results close to a human expert. The experimental results suggest that such a system is valuable both for less experienced clinicians and for experts where the system may function as a second option.

  • 32.
    Ahmed, Mobyen Uddin
    Mälardalen University, School of Innovation, Design and Engineering.
    A Multimodal Approach for Clinical Diagnosis and Treatment2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    A computer-aided Clinical Decision Support System (CDSS) for diagnosis and treatment often plays a vital role and brings essential benefits for clinicians. Such a CDSS could function as an expert for a less experienced clinician or as a second option/opinion of an experienced clinician to their decision making task. Nevertheless, it has been a real challenge to design and develop such a functional system where accuracy of the system performance is an important issue.

    This research work focuses on development of intelligent CDSS based on a multimodal approach for diagnosis, classification and treatment in medical domains i.e. stress and post-operative pain management domains. Several Artificial Intelligence (AI) techniques such as Case-Based Reasoning (CBR), textual Information Retrieval (IR), Rule-Based Reasoning (RBR), Fuzzy Logic and clustering approaches have been investigated in this thesis work.

    Patient’s data i.e. their stress and pain related information are collected from complex data sources for instance, finger temperature measurements through sensor signals, pain measurements using a Numerical Visual Analogue Scale (NVAS), patient’s information from text and multiple choice questionnaires. The proposed approach considers multimedia data management to be able to use them in CDSSs for both the domains.

    The functionalities and performance of the systems have been evaluated based on close collaboration with experts and clinicians of the domains. In stress management, 68 measurements from 46 subjects and 1572 patients’ cases out of ≈4000 in post-operative pain have been used to design, develop and validate the systems. In the stress management domain, besides the 68 measurement cases, three trainees and one senior clinician also have been involved in order to conduct the experimental work. The result from the evaluation shows that the system reaches a level of performance close to the expert and better than the senior and trainee clinicians. Thus, the proposed CDSS could be used as an expert for a less experienced clinician (i.e. trainee) or as a second option/opinion for an experienced clinician (i.e. senior) to their decision making process in stress management. In post-operative pain treatment, the CDSS retrieves and presents most similar cases (e.g. both rare and regular) with their outcomes to assist physicians. Moreover, an automatic approach is presented in order to identify rare cases and 18% of cases from the whole cases library i.e. 276 out of 1572 are identified as rare cases by the approach. Again, among the rare cases (i.e. 276), around 57.25% of the cases are classified as ‘unusually bad’ i.e. the average pain outcome value is greater or equal to 5 on the NVAS scale 0 to 10. Identification of rear cases is an important part of the PAIN OUT project and can be used to improve the quality of individual pain treatment.

  • 33.
    Ahmed, Mobyen Uddin
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Altarabichi, Mohammed Ghaith
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Begum, Shahina
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Ginsberg, Fredrik
    Mälardalens högskola, Västerås, Sweden.
    Glaes, Robert
    Mälardalens högskola, Västerås, Sweden.
    Östgren, Magnus
    Mälardalens högskola, Västerås, Sweden.
    Rahman, Hamidur
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Sorensen, Magnus
    Mälardalens högskola, Västerås, Sweden.
    Avision-based indoor navigation system for individuals with visual impairment2019In: International Journal of Artificial Intelligence, ISSN 0974-0635, E-ISSN 0974-0635, Vol. 17, no 2, p. 188-201Article in journal (Refereed)
    Abstract [en]

    Navigation and orientation in an indoor environment are a challenging task for visually impaired people. This paper proposes a portable vision-based system to provide support for visually impaired persons in their daily activities. Here, machine learning algorithms are used for obstacle avoidance and object recognition. The system is intended to be used independently, easily and comfortably without taking human help. The system assists in obstacle avoidance using cameras and gives voice message feedback by using a pre-trained YOLO Neural Network for object recognition. In other parts of the system, a floor plane estimation algorithm is proposed for obstacle avoidance and fuzzy logic is used to prioritize the detected objects in a frame and generate alert to the user about possible risks. The system is implemented using the Robot Operating System (ROS) for communication on a Nvidia Jetson TX2 with a ZED stereo camera for depth calculations and headphones for user feedback, with the capability to accommodate different setup of hardware components. The parts of the system give varying results when evaluated and thus in future a large-scale evaluation is needed to implement the system and get it as a commercialized product in this area.

  • 34.
    Ahmed, Mobyen Uddin
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Begum, Shahina
    Mälardalen University, School of Innovation, Design and Engineering.
    Funk, Peter
    Mälardalen University, School of Innovation, Design and Engineering.
    A Hybrid Case-Based System in Stress Diagnosis and Treatment2012Manuscript (preprint) (Other academic)
    Abstract [en]

    Computer-aided decision support systems play anincreasingly important role in clinical diagnosis and treatment.However, they are difficult to build for domains where thedomain theory is weak and where different experts differ indiagnosis. Stress diagnosis and treatment is an example of such adomain. This paper explores several artificial intelligencemethods and techniques and in particular case-based reasoning,textual information retrieval, rule-based reasoning, and fuzzylogic to enable a more reliable diagnosis and treatment of stress.The proposed hybrid case-based approach has been validated byimplementing a prototype in close collaboration with leadingexperts in stress diagnosis. The obtained sensitivity, specificityand overall accuracy compared to an expert are 92%, 86% and88% respectively.

  • 35.
    Ahmed, Mobyen Uddin
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Begum, Shahina
    Mälardalen University, School of Innovation, Design and Engineering.
    Funk, Peter
    Mälardalen University, School of Innovation, Design and Engineering.
    Xiong, Ning
    Mälardalen University, School of Innovation, Design and Engineering.
    FUZZY RULE-BASED CLASSIFICATION TO BUILD INITIAL CASE LIBRARY FOR CASE-BASED STRESS DIAGNOSIS2009In: Proceedings of the IASTED International Conference on Artificial Intelligence and Applications, AIA 2009 / [ed] M.H. Hamza, 2009, p. 225-230Conference paper (Refereed)
    Abstract [en]

    Case-Based Reasoning (CBR) is receiving increasedinterest for applications in medical decision support.Clinicians appreciate the fact that the system reasons withfull medical cases, symptoms, diagnosis, actions takenand outcomes. Also for experts it is often appreciated toget a second opinion. In the initial phase of a CBR systemthere are often a limited number of cases available whichreduces the performance of the system. If past cases aremissing or very sparse in some areas the accuracy isreduced. This paper presents a fuzzy rule-basedclassification scheme which is introduced into the CBRsystem to initiate the case library, providing improvedperformance in the stress diagnosis task. Theexperimental results showed that the CBR system usingthe enhanced case library can correctly classify 83% ofthe cases, whereas previously the correctness of theclassification was 61%. Consequently the proposedsystem has an improved performance with 22% in termsof accuracy. In terms of the discrepancy in classificationcompared to the expert, the goodness-of-fit value of thetest results is on average 87%. Thus by employing thefuzzy rule-based classification, the new hybrid system cangenerate artificial cases to enhance the case library.Furthermore, it can classify new problem cases previouslynot classified by the system.

  • 36.
    Ahmed, Mobyen Uddin
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Brickman, Staffan
    Mälardalens högskola, Vasteras, Sweden.
    Dengg, Alexander
    Mälardalens högskola, Vasteras, Sweden.
    Fasth, Niklas
    Mälardalens högskola, Vasteras, Sweden.
    Mihajlovic, Marko
    Mälardalens högskola, Vasteras, Sweden.
    Norman, Jacob
    Mälardalens högskola, Vasteras, Sweden.
    A machine learning approach to classify pedestrians’ events based on IMU and GPS2019In: International Journal of Artificial Intelligence, ISSN 0974-0635, E-ISSN 0974-0635, Vol. 17, no 2, p. 154-167Article in journal (Refereed)
    Abstract [en]

    This paper investigates and implements six Machine Learning (ML) algorithms, i.e. Artificial Neural Network (ANN), Support Vector Machine (SVM), Decision Tree (DT), Random Forest (RF), Extra Tree (ET), and Gradient Boosted Trees (GBT) to classify different Pedestrians’ events based on Inertial Measurement Unit (IMU) and Global Positioning System (GPS) signals. Pedestrians’ events are pedestrian movements as the first step of H2020 project called SimuSafe1 with a goal to reduce traffic fatalities by doing risk assessments of the pedestrians. The movements the MLs’ models are attempting to classify are standing, walking, and running. Data, i.e. IMU, GPS sensor signals and other contextual information are collected by a smartphone through a controlled procedure. The smartphone is placed in five different positions onto the body of participants, i.e. arm, chest, ear, hand and pocket. The recordings are filtered, trimmed, and labeled. Next, samples are generated from small overlapping sections from which time and frequency domain features are extracted. Three different experiments are conducted to evaluate the performances in term of accuracy of the MLs’ models in different circumstances. The best performing MLs’ models determined by the average accuracy across all experiments is Extra Tree (ET) with a classification accuracy of 91%. 

  • 37.
    Ahmed, Mobyen Uddin
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Funk, Peter
    Mälardalen University, School of Innovation, Design and Engineering.
    A Case-Based Retrieval System for Post-Operative Pain Treatment2011In: / [ed] Petra Perner and Georg Rub, Germany: IBaI , 2011, p. 30-41Conference paper (Refereed)
    Abstract [en]

    This paper presents a clinical decision support system based on case-basedretrieval approach to assist physicians in post-operative pain treatment. Here,the cases are formulated by combining regular features and features using anumerical visual analogue scale (NVAS) through a questionnaire. Featureabstraction is done both in problem and outcome description of a case in order toreduce the number of attributes. The system retrieves most similar cases with theiroutcomes. The outcome of each case brings benefits for physicians since it presentsboth severity and fast recovery by the applied treatment in post-operative patients.Therefore, we have introduced a two-layer case structure i.e., solution is the firstlayer and outcome is the second layer that better suits this medical application. Inthe system, the solution presents the treatment and the outcome contains recoveryinformation of a patient, something physicians are interested in, especially the riskof side effects and complications.

  • 38.
    Ahmed, Mobyen Uddin
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Funk, Peter
    Mälardalen University, School of Innovation, Design and Engineering.
    Mining Rare Cases in Post-Operative Pain by Means of Outlier Detection2011Manuscript (preprint) (Other academic)
    Abstract [en]

    Rare cases are often interesting for healthprofessionals, physicians, researchers and clinicians in order toreuse and disseminate experiences in healthcare. However,mining, i.e. identification of rare cases in electronic patientrecords, is non-trivial for information technology. This paperinvestigates a number of well-known clustering algorithms andfinally applies a 2nd order clustering approach by combining theFuzzy C-means algorithm with the Hierarchical one. Theapproach is used in order to identify rare cases from 1572patient cases in the domain of post-operative pain management.The results show that the approach enables identification of rarecases in the domain of post-operative pain management and 18%of cases are identified as rare case.

  • 39.
    Ahmed, Mohamed Ali
    Mälardalen University, School of Innovation, Design and Engineering.
    Eliciting correlations between components selection decision cases in software architecting2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A key factor of software architecting is the decision-making process. All phases of software development contain some kind of decision-making activities. However, the software architecture decision process is the most challenging part. To support the decision-making process, a research project named ORION provided a knowledge repository that contains a collection of decision cases. To utilize the collected data in an efficient way, eliciting correlations between decision cases needs to be automated. 

    The objective of this thesis is to select appropriate method(s) for automatically detecting correlations between decision cases. To do this, an experiment was conducted using a dataset of collected decision cases that are based on a taxonomy called GRADE. The dataset is stored in the Neo4j graph database. The Neo4j platform provides a library of graph algorithms which allow to analyse a number of relationships between connected data. In this experiment, five Similarity algorithms are used to find correlated decisions, then the algorithms are analysed to determine whether the they would help improve decision-making. 

    From the results, it was concluded that three of the algorithms can be used as a source of support for decision-making processes, while the other two need further analyses to determine if they provide any support. 

  • 40.
    Ajmaya, Davi
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Eklund, Dennis
    Mälardalen University, School of Innovation, Design and Engineering.
    Machine learning based pedestrian event monitoring using IMU and GPS2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Understanding the behavior of pedestrians in road transportation is critical to maintain a safe en- vironment. Accidents on road transportation are one of the most common causes of death today. As autonomous vehicles start to become a standard in our society, safety on road transportation becomes increasingly important. Road transportation is a complex system with a lot of dierent factors. Identifying risky behaviors and preventing accidents from occurring requires better under- standing of the behaviors of the dierent persons involved. In this thesis the activities and behavior of a pedestrian is analyzed. Using sensor data from phones, eight dierent events of a pedestrian are classied using machine learning algorithms. Features extracted from phone sensors that can be used to model dierent pedestrian activities are identied. Current state of the art literature is researched to nd relevant machine learning algorithms for a classication model. Two models are implemented using two dierent machine learning algorithms: Articial Neural Network and Hid- den Markov Model. Two dierent experiments are conducted where phone sensor data is collected and classied using the models, achieving a classication accuracy of up to 93%.

  • 41.
    Akalin, Neziha
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kiselev, Andrey
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    An Evaluation Tool of the Effect of Robots in Eldercare on the Sense of Safety and Security2017In: Social Robotics: 9th International Conference, ICSR 2017, Tsukuba, Japan, November 22-24, 2017, Proceedings / [ed] Kheddar, A.; Yoshida, E.; Ge, S.S.; Suzuki, K.; Cabibihan, J-J:, Eyssel, F:, He, H., Springer International Publishing , 2017, p. 628-637Conference paper (Refereed)
    Abstract [en]

    The aim of the study presented in this paper is to develop a quantitative evaluation tool of the sense of safety and security for robots in eldercare. By investigating the literature on measurement of safety and security in human-robot interaction, we propose new evaluation tools. These tools are semantic differential scale questionnaires. In experimental validation, we used the Pepper robot, programmed in the way to exhibit social behaviors, and constructed four experimental conditions varying the degree of the robot’s non-verbal behaviors from no gestures at all to full head and hand movements. The experimental results suggest that both questionnaires (for the sense of safety and the sense of security) have good internal consistency.

  • 42.
    Akalin, Neziha
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kiselev, Andrey
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    The Relevance of Social Cues in Assistive Training with a Social Robot2018In: 10th International Conference on Social Robotics, ICSR 2018, Proceedings / [ed] Ge, S.S., Cabibihan, J.-J., Salichs, M.A., Broadbent, E., He, H., Wagner, A., Castro-González, Á., Springer , 2018, p. 462-471Conference paper (Refereed)
    Abstract [en]

    This paper examines whether social cues, such as facial expressions, can be used to adapt and tailor a robot-assisted training in order to maximize performance and comfort. Specifically, this paper serves as a basis in determining whether key facial signals, including emotions and facial actions, are common among participants during a physical and cognitive training scenario. In the experiment, participants performed basic arm exercises with a social robot as a guide. We extracted facial features from video recordings of participants and applied a recursive feature elimination algorithm to select a subset of discriminating facial features. These features are correlated with the performance of the user and the level of difficulty of the exercises. The long-term aim of this work, building upon the work presented here, is to develop an algorithm that can eventually be used in robot-assisted training to allow a robot to tailor a training program based on the physical capabilities as well as the social cues of the users.

  • 43.
    Akalin, Neziha
    et al.
    Örebro University, Sweden.
    Kristoffersson, Annica
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Loutfi, Amy
    Örebro University, Sweden.
    The Influence of Feedback Type in Robot-Assisted Training2019In: Multimodal Technologies and Interaction, ISSN 2414-4088, Vol. 4, no 3, article id 67Article in journal (Refereed)
    Abstract [en]

    Robot-assisted training, where social robots can be used as motivational coaches, provides an interesting application area. This paper examines how feedback given by a robot agent influences the various facets of participant experience in robot-assisted training. Specifically, we investigated the effects of feedback type on robot acceptance, sense of safety and security, attitude towards robots and task performance. In the experiment, 23 older participants performed basic arm exercises with a social robot as a guide and received feedback. Different feedback conditions were administered, such as flattering, positive and negative feedback. Our results suggest that the robot with flattering and positive feedback was appreciated by older people in general, even if the feedback did not necessarily correspond to objective measures such as performance. Participants in these groups felt better about the interaction and the robot.

  • 44.
    Akan, Batu
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Planning and Sequencing Through Multimodal Interaction for Robot Programming2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Over the past few decades the use of industrial robots has increased the efficiency as well as the competitiveness of several sectors. Despite this fact, in many cases robot automation investments are considered to be technically challenging. In addition, for most small and medium-sized enterprises (SMEs) this process is associated with high costs. Due to their continuously changing product lines, reprogramming costs are likely to exceed installation costs by a large margin. Furthermore, traditional programming methods of industrial robots are too complex for most technicians or manufacturing engineers, and thus assistance from a robot programming expert is often needed. The hypothesis is that in order to make the use of industrial robots more common within the SME sector, the robots should be reprogrammable by technicians or manufacturing engineers rather than robot programming experts. In this thesis, a novel system for task-level programming is proposed. The user interacts with an industrial robot by giving instructions in a structured natural language and by selecting objects through an augmented reality interface. The proposed system consists of two parts: (i) a multimodal framework that provides a natural language interface for the user to interact in which the framework performs modality fusion and semantic analysis, (ii) a symbolic planner, POPStar, to create a time-efficient plan based on the user's instructions. The ultimate goal of this work in this thesis is to bring robot programming to a stage where it is as easy as working together with a colleague.This thesis mainly addresses two issues. The first issue is a general framework for designing and developing multimodal interfaces. The general framework proposed in this thesis is designed to perform natural language understanding, multimodal integration and semantic analysis with an incremental pipeline. The framework also includes a novel multimodal grammar language, which is used for multimodal presentation and semantic meaning generation. Such a framework helps us to make interaction with a robot easier and more natural. The proposed language architecture makes it possible to manipulate, pick or place objects in a scene through high-level commands. Interaction with simple voice commands and gestures enables the manufacturing engineer to focus on the task itself, rather than the programming issues of the robot. The second issue addressed is due to inherent characteristics of communication with the use of natural language; instructions given by a user are often vague and may require other actions to be taken before the conditions for applying the user's instructions are met. In order to solve this problem a symbolic planner, POPStar, based on a partial order planner (POP) is proposed. The system takes landmarks extracted from user instructions as input, and creates a sequence of actions to operate the robotic cell with minimal makespan. The proposed planner takes advantage of the partial order capabilities of POP to execute actions in parallel and employs a best-first search algorithm to seek the series of actions that lead to a minimal makespan. The proposed planner can also handle robots with multiple grippers, parallel machines as well as scheduling for multiple product types.

  • 45.
    Akan, Batu
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Ameri E., Afshin
    Mälardalen University, School of Innovation, Design and Engineering.
    Çürüklü, Baran
    Mälardalen University, School of Innovation, Design and Engineering.
    Augmented Reality-based Industrial Robot Control2011In: Proceedings of SIGRAD 2011 / [ed] Larsson, Thomas ; Kjelldahl, Lars ; Jää-Aro, Kai-Mikael, Linköping University Electronic Press, 2011, p. 113-114Conference paper (Refereed)
    Abstract [en]

    Most of the interfaces which are designed to control or program industrial robots are complex and require special training for the user. This complexity alongside the changing environment of small medium enterprises (SMEs) has lead to absence of robots from SMEs. The costs of (re)programming the robots and (re)training the robot users exceed initial costs of installation. In order to solve this shortcoming, we propose a new interface which uses augmented reality (AR) and multimodal human-robot interaction. We show that such an approach allows easier manipulation of robots at industrial environments.

  • 46.
    Aksit, Kaan
    et al.
    Koç University, Turkey.
    Kade, Daniel
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Özcan, Oguzhan
    Koç University, Turkey.
    Ürey, Hakan
    Koç University, Turkey.
    Head-worn Mixed Reality Projection Display Application2014In: ACM International Conference Proceedings Series (ICPS), 2014Conference paper (Refereed)
    Abstract [en]

    The main goal of this research is to develop a mixed real- ity (MR) application to support motion capture actors. This application allows seeing and exploring a digital environment without occluding the actor’s visual field. A prototype is built by combining a retro-reflective screen covering surrounding walls and a headband consisting of a laser scanning projector with a smartphone. Built-in sensors of a smartphone provide navigation capabilities in the digital world. The integrated system has some unique advantages, which are collectively demonstrated for the first time: (i) providing fixed field-of- view (50o in diagonal), fixed retinal images at full-resolution, and distortion-free images that are independent of the screen distance and shape; (ii) presenting different perspectives to the users as they move around or tilt their heads, (iii) allow- ing a focus-free and calibration-free display even on non-flat surfaces using laser scanning technology, (iv) enabling mul- tiple users to share the same screen without crosstalk due to the use of retro-reflectors, and (v) producing high brightness pictures with a projector of only 15 lm; due to a high-gain retro-reflective screen. We demonstrated a lightweight, com- fortable to wear and low cost head-mounted projection dis- play (HMPD) which acts as a stand-a-lone mobile system. Initial informal functionality tests have been successfully per- formed. The prototype can also be used as a 3D stereo system using the same hardware by additionally mounting polarized glasses and an active polarization rotator, while maintaining all of the advantages listed above. 

  • 47.
    Alajrami, S.
    et al.
    Newcastle University, Newcastle upon Tyne, United Kingdom.
    Romanovsky, A.
    Newcastle University, Newcastle upon Tyne, United Kingdom.
    Gallina, Barbara
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Software development in the Post-PC era: Towards software development as a service2016In: Lect. Notes Comput. Sci., 2016, p. 662-671Conference paper (Refereed)
    Abstract [en]

    Over the years, software development has evolved to meet the needs of new types of applications and to embrace new technological disruptions. Today, we witness the rise of mobility where the role of the conventional high-end PC is declining. Some refer to this era as the Post- PC era. This technological shift, powered by a key enabling technology, cloud computing, has opened new opportunities for human advancement. Consequently, the evolving landscape of software systems drives the need for new methods for conceiving them. Such methods need to: (a) address the challenges and requirements of this era and (b) embrace the benefits of new technological breakthroughs. In this paper, we list the characteristics of the Post-PC era from the software development perspective and describe two motivating trends of software development processes. Then, we derive a list of requirements for the future software development from the characteristics of the Post-PC era and from the motivating trends. Finally, we propose a reference architecture for cloud-based software process enactment as an enabler for Software Development as a Service. The architecture is the first step addressing the needs that we have identified.

  • 48.
    Alam, Usman
    Mälardalen University, School of Innovation, Design and Engineering.
    Music in Motion - Smart Soundscapes2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 49.
    Alape Vivekananda, Ashish
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Test Generation For Digital Circuits – A Mapping Study On VHDL, Verilog and SystemVerilog2018Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Researchers have proposed different methods for testing digital logic circuits. The need for testing digital logic circuits has become more important than ever due to the growing complexity of such systems. During the development process, testing is focusing on design defects as well as manufacturing and wear out type of defects. Failures in digital systems could be caused by design errors, the use of inherently probabilistic devices, and manufacturing variability. The research in this area has focused also on the design of digital logic circuit for achieving better testability. In addition, automated test generation has been used to create tests that can quickly and accurately identify faulty components. Examples of such methods are the Ad Hoc techniques, Scan Path Technique for testable sequential circuits, and the random scan technique. With the research domain becoming more mature and the number of related studies increasing, it is essential to systematically identify, analyse and classify the papers in this area. The systematic mapping study of testing digital circuits performed in this thesis aims at providing an overview of the research trends in this domain and empirical evidence. In order to restrict the scope of the mapping study we only focus on some of the most widely-used and well-supported hardware description languages (HDLs): Verilog, SystemVerilog and VHDL. Our results suggest that most of the methods proposed for test generation of digital circuits are focused on the behavioral level and Register Transfer Levels. Fault independent test generation is the most frequently applied test goal and simulation is the most common experimental test evaluation method. Majority of papers published in this area are conference papers and the publication trend shows a growing interest in this area. 63% of papers execute the test method proposed. An equal percentage of papers experimetnatlly evaluate the test method they propose. From the mapping study we inferred that papers that execute the test method proposed, evaluate them as well.

  • 50.
    Alemzadeh, H.
    et al.
    University of Virginia, Virginia, United States.
    Gallina, Barbara
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Natella, R.
    Federico II University of Naples, Naples, Italy.
    Netkachova, K.
    University of London, London, United Kingdom.
    Pietrantuono, R.
    Federico II University of Naples, Naples, Italy.
    Silva, N.
    CRITICAL Software S.A., Portugal.
    Message from the WoSoCer 2018 Workshop Chairs2018In: Proceedings - 29th IEEE International Symposium on Software Reliability Engineering Workshops, ISSREW 2018, Institute of Electrical and Electronics Engineers Inc. , 2018, article id 8539151Conference paper (Other academic)
1234567 1 - 50 of 1032
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf