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  • 51.
    Achrenius, William
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Bergman Törnkvist, Martin
    Mälardalens högskola, Akademin för innovation, design och teknik.
    GRAPH GENERATION ALGORITHMS FOR THE GRADE DECISION CANVAS2018Independent thesis Basic level (degree of Bachelor), 12 hpOppgave
    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.

  • 52.
    Achuthan, K.
    et al.
    Amrita Center for Cybersecurity Systems and Networks, Kerala, India.
    Ramesh, M. V.
    Amrita Center for International Programs, Kerala, India.
    Punnekkat, Sasikumar
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Raman, R.
    Center for Research in Advanced Technologies for Education, Kerala, India.
    Internationalizing engineering education with phased study programs: India-European experience2015Inngår i: Proceedings - Frontiers in Education Conference, FIE, 2015, nr FebruaryKonferansepaper (Fagfellevurdert)
    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.

  • 53.
    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
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Raman, Raghu
    Amrita Vishwa Vidyapeetham, Ctr Res Adv Technol Educ, Kollam, Kerala, India..
    Internationalizing Engineering Education With Phased Study Programs: India-European Experience2014Inngår i: 2014 IEEE FRONTIERS IN EDUCATION CONFERENCE (FIE), IEEE , 2014, s. 295-301Konferansepaper (Fagfellevurdert)
    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.

  • 54.
    Acimovic, Aleksandar
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Bajceta, Aleksandar
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Test script design approaches supporting reusability, maintainability and review process2019Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    Software testing is widely considered to be one of the most important parts of software development life-cycle. In this research, we investigated potential improvements in the testing process and design of automated test scripts inside Bombardier Transportation. For the creation of automated test scripts BT is using a group of programs called TAF (Test Automation Framework). These scripts are used for testing Train Control Management System (TCMS), software that is used for managing the train. TAF can export its test scripts in XML format. XML scripts are analyzed in order to identify the most frequent changes. To better understand the life cycle of automated Test scripts official documentation that defines the Verification and Validation process inside BT was analyzed. Also, an interview was conducted with one of the responsible persons for testing. We believe that we have found a possible solution for improving testing process and creation of automated test scripts in BT, and to evaluate it proof of concept tool was developed. The main idea behind the tool is to write the test script using keywords which are based on analysis that was conducted on test specification documentation. These keywords represent frequent actions that are being tested on the train. By storing those actions in keywords re-usability of test script is being increased. Also, because they are based on naturally language, they are having positive effect on readability and maintenance of the test script.

  • 55.
    Adam, Hemin
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Cost effect by implementing LEAN2014Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This report is a result of master thesis performed at Volvo Powertrain in Koping, Sweden. Today Volvo Powertrain processes and assembles gearboxes for many of Volvo trucks, buses and dump trucks. It also sends gearbox components to Volvo’s plants in North and South Americas, and additionally produces Volvo Penta’s revolutionary marine gear called “IPS” within the company.In order to meet customer requirements for reduced lead time/ freezing time for order placement of products in Koping, Volvo Powertrain wants to achieve a more resource-efficient production. What will the economic costs be in order to reduce the lead time and implement improvements? Since all decision includes cost investment.The aim of this thesis is to make a deep analysis of Order-To-Delivery process between the customers of Volvo Penta, Volvo VCE as well as aftermarket and clarifying the impact of lead time shortening both in practical and economical point of view.After completing the Value Stream Mapping on the current state, problems and non-value adding time are identified. Problems that are found are the long waiting time between the machines, which is the majority of the throughput time. Other issues are the long setup time, and operations that are not performed correctly. Other types of waste were also observed included the long waiting time of material handling between the different buildings.Based on the Value Stream Mapping and through other Lean tools, various proposals have been presented to simplify and increase machine time availability and flexible the production. There have also been various scenarios calculated about what the economic costs will be if the selected items in this thesis are prioritized over other products.

  • 56.
    Adamsson, Maximilian
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Enehöjd, Pontus
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Värdeerbjudande i fysisk butik jämfört med den digitala handeln: En studie om hur värdeerbjudandet upplevs av kunderna i syfte att kunna skapa bättre samverkan mellan fysisk och digitala försäljningskanaler2019Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Detaljhandeln står inför ett stort skifte för att kunna tillgodose alla de nya krav som kunderna sätter på företagen. Företag och organisationer behöver hantera digitaliseringen som sker och förändrar deras marknad otroligt snabbt. Denna studie har för avsikt att skapa underlag för en innovativ affärsmodell. Denna modell ska bidra till att hjälpa organisationer, att skapa en bild för hur organisationer behöver använda tid och resurser till att kunna vara relevanta men också utvecklas i och med den förändrande marknaden. Fokus i studien ligger på vilket sorts värde kunderna erbjuds samt hur fysisk och digital handel kan samverka. I samarbete med Lindex, en väldigt stor aktör inom detaljhandeln, med sitt fokus på kläder för kvinnor och barn. En induktiv forskningsmetod med kvalitativa intervjuer som grund användes för att samla in data. I och med dessa intervjuer kunde åsikter och tankar från medlemmar inom organisationen, samt kunder med perspektiv från utifrån fångas upp för att skapa en heltäckande bild hur organisationen ser ut och uppfattades.Det som studien visade var att värdeerbjudandet skiljer sig i den fysiska och digitala handeln men de visade även att erbjudandet i de olika kanalerna bör inte vara densamma. Utan istället skapa en mer personlig upplevelse för kunden. Som hjälper kunden vare sig de väljer att handla online eller i fysisk butik.I studien framgår det även hur den individuella servicen som personalen kan ge genom rekommendationer och inspiration utifrån kundens tidigare köp. Det tillsammans med vad som är de nya trenderna för tillfället för att kunna ge ett mer helhetserbjudande med individualitet till deras kunder.Med hjälp av studiens handledare Handledare Erik Lindhult. Skriven av Pontus Enehöjd & Maximilian Adamsson.

  • 57.
    Addazi, Lorenzo
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Automated Synthesis of Model Comparison Benchmarks2019Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Model-driven engineering promotes the migration from code-centric to model-based software development. Systems consist of model collections integrating different concerns and perspectives, while semi-automated model transformations generate executable code combining the information from these. Increasing the abstraction level to models required appropriate management technologies supporting the various software development activities. Among these, model comparison represents one of the most challenging tasks and plays an essential role in various modelling activities. Its hardness led researchers to propose a multitude of approaches adopting different approximation strategies and exploiting specific knowledge of the involved models. However, almost no support is provided for their evaluation against specific scenarios and modelling practices. This thesis presents Benji, a framework for the automated generation of model comparison benchmarks. Given a set of differences and an initial model, users generate models resulting from the application of the first on the latter. Differences consist of preconditions, actions and postconditions expressed using a dedicated specification language. The generator converts benchmark specifications to design-space exploration problems and produces the final solutions along with a model-based description of their differences with respect to the initial model. A set of representative use cases is used to evaluate the framework against its design principles, which resemble the essential properties expected from model comparison benchmark generators.

  • 58.
    Addazi, Lorenzo
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Cicchetti, Antonio
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. IS (Embedded Systems).
    Di Rocco, Juri
    University of L’Aquila, Italy.
    Di Ruscio, Davide
    University of L’Aquila, Italy.
    Iovino, Ludovico
    University of L’Aquila, Italy.
    Pierantonio, Alfonso
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. University of L’Aquila, Italy.
    Semantic-based Model Matching with EMFCompare2016Inngår i: CEUR Workshop Proceedings (CEUR-WS.org), Saint Malo, France: CEUR-WS , 2016, Vol. 1706, s. 40-49Konferansepaper (Fagfellevurdert)
  • 59.
    Addazi, Lorenzo
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Ciccozzi, Federico
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Langer, Philip
    EclipsSource, Austria.
    Posse, Ernesto
    Zeligsoft, Canada.
    Towards Seamless Hybrid Graphical-Textual Modelling for UML and Profiles2017Inngår i: Lecture Notes in Computer Science, vol. 10376, Springer, 2017, s. 20-33Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Domain-specific modelling languages, in particular those described in terms of UML profiles, use graphical notations to maximise human understanding and facilitate communication among stakeholders. Nevertheless, textual notations are preferred for specific purposes, due to the nature of a specific domain, or for personal preference. The mutually exclusive use of graphical or textual modelling is not sufficient for the development of complex systems developed by large heterogeneous teams. We envision a modern modelling framework supporting seamless hybrid graphical and textual modelling. Such a framework would provide several benefits, among which: flexible separation of concerns, multi-view modelling based on multiple notations, convenient text-based editing operations, and text-based model editing outside the modelling environment, and faster modelling activities. In this paper we describe our work towards such a framework for UML and profiles. The uniqueness is that both graphical and textual modelling are done on a common persistent model resource, thus dramatically reducing the need for synchronisation among the two notations.

  • 60.
    Addazi, Lorenzo
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Ciccozzi, Federico
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Lisper, Björn
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Executable modelling for highly parallel accelerators2019Inngår i: Proceedings - 2019 ACM/IEEE 22nd International Conference on Model Driven Engineering Languages and Systems Companion, MODELS-C 2019, Institute of Electrical and Electronics Engineers Inc. , 2019, s. 318-321, artikkel-id 8904827Konferansepaper (Fagfellevurdert)
    Abstract [en]

    High-performance embedded computing is developing rapidly since applications in most domains require a large and increasing amount of computing power. On the hardware side, this requirement is met by the introduction of heterogeneous systems, with highly parallel accelerators that are designed to take care of the computation-heavy parts of an application. There is today a plethora of accelerator architectures, including GPUs, many-cores, FPGAs, and domain-specific architectures such as AI accelerators. They all have their own programming models, which are typically complex, low-level, and involve explicit parallelism. This yields error-prone software that puts the functional safety at risk, unacceptable for safety-critical embedded applications. In this position paper we argue that high-level executable modelling languages tailored for parallel computing can help in the software design for high performance embedded applications. In particular, we consider the data-parallel model to be a suitable candidate, since it allows very abstract parallel algorithm specifications free from race conditions. Moreover, we promote the Action Language for fUML (and thereby fUML) as suitable host language.

  • 61.
    Adelmar, Catrine
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Modell för navigering i Scania Multis digitala verkstadshandbok2008Oppgave
    Abstract [sv]

    Problem

    Funktioner i tunga fordon går allt mer från att vara mekaniska till att styras med hjälp av elektroniska signaler. För att förstå hur komponenter och system fungerar och ska repareras har mekanikerna Verkstadshandboken till sin hjälp. Från tryckt media har Verkstadshandboken övergått till digital publicering i visningsprodukten Scania Multi.

     

    Scania Multi var inledningsvis ett program för reservdelsinformation och har en navigeringsstruktur som är anpassad efter komponenternas placering på fordonet. Det är inte logiskt att hitta information om hur system och komponenter fungerar och ska lagas när man följer en navigeringsstruktur som från början är avsedd för reservdelar, det märks. Mekanikerna som använder Verkstadshandboken i Scania Multi har klagat över att information för reparationer och funktionsbeskrivningar inte finns. Ofta visar det sig att informationen faktiskt finns där men har varit svår att hitta.

    Metod

    Vilka risker och hinder finns det som påverkar om man vill eller orkar ta del av information? Olika signaler från vår omgivning påverkar våra val och beteenden och avgör om ett budskap når fram eller inte. Signalerna inverkar alltså på de val vi gör när vi ställs inför en ny situation.

     

    För att budskapet ska nå ända fram måste signalen vara rätt, ren och stark. Inom området informationsarkitektur pratar man om hur olika sorters design påverkar våra val och handlingar när vi ska interagera med ett digitalt informationsmaterial. Här pratar man om grafisk, informations- och interaktionsdesign. Jag har kopplat de olika typerna av design med de tre olika signalerna.

     

    Utifrån resonemanget om att rätt, ren och stark signal kan jämställas med informationsarkitekturens olika sorters design, gjorde jag en prototyp. Prototypens informationsdesign bygger på att jag har använt och strukturerat informationen med hjälp av den del i ISO standarden STEP som kallas Product Life Cycle Support. När jag sorterade informationen inom de olika avdelningarna använde jag mig av Information Mapping metoden.

     

    Prototypen har en fysisk och en funktionell vy som ska stödja mekanikernas behov när de använder Verkstadshandboken. För att ta reda på hur signalerna i prototypen fungerade testade jag den på sju yrkesverksamma mekaniker. Användningstestet byggde på två scenarion med tillhörande uppgifter där syftet var att få återkoppling på prototypens design och hitta förbättringspunkter.

    Slutsats

    Användningstesterna fokuserade framförallt på prototypens informationsdesign men berörde även prototypens grafiska design och gav vägledning om interaktionsdesignen var på rätt väg. Med hjälp av användningstesterna kunde jag analysera resultatet för att se vad som borde förbättras.

     

    Eftersom mekaniker inte har fått vara med och kravställa designen fick de interagera med en produkt som inte var optimal för deras behov. Mekanikerna är vana vid strukturen i nuvarande Verkstadshandboken i Scania Multi. Den nya strukturen tar hänsyn till fordonets funktionalitet på ett sätt som inte presenteras i dagens system.

     

    Det var fyra avsnitt där mekanikernas återkoppling på prototypens design var extra tydlig:

    -       Det var svårt att se knappar och klickbara länkar.

    -       Designen uppfattades som rörig.

    -       När man väl hade förstått informationsdesignen var det lätt att se att den skulle kunna vara till stor hjälp vid exempelvis felsökning.

    -       Uppdelningen av informationen upplevdes positivt när man hade vant sig vid de olika vyerna.

  • 62.
    Adolfsson, Emma
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Ergül, Caroline
    Reducering av produktionstryck i A-linan: Förflyttning av produkt2013Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
  • 63.
    Adolfsson, Emma
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Lindgren, Peder
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Managing Transfer Projects in an Offshore Strategy: Swedish and Chinese Perspectives2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Offshoring concerns the relocation or a transfer of a company’s business activities to another country. When a company decides to offshore their business to another location it involves the transfer of products and knowledge which are both key activities in transfer projects. In today’s globalization it is difficult for companies to stay competitive in the marketplace. For this reason it is becoming more common that companies offshore parts of their business and opening affiliates abroad for the production of goods or services. It is challenging to transfer a product from one site to one other since the receiving site might not have been involved in the product development process from the beginning and therefore have limited associations to the product. The transfer of competence and knowledge but also different ways of working are some of the factors that needs to be successfully managed. This makes it especially challenging when considering cultural and geographical together with the temporal distance between the sites. It is difficult for companies to maintain a sourcing strategy that is cohesive and many companies therefor fails to manage a successful relationship with their offshore partners. The purpose with this study was to present a framework that would support the transfer process when aiming for parallel production. This was to include the features needed to be developed in order to manage the most important factors in the transfer process.

    In order to answer the research questions a case study with a qualitative research method was performed. Interviews in Sweden and China including 34 respondents were performed in order to identify the transfer process. The approach was a qualitative interview with a guided conversation with the emphasis on the authors asking questions and listening, and the respondent answering. The respondents was seen as meaning makers rather than passive channels for retrieving the data needed. The purpose was to derive interpretations rather than facts or laws. Each interview was conducted between three people including the two authors and one respondent.

    The findings indicate that the organization needs to improve their knowledge transfer process. The organization also needs to develop similar processes for the activities involved in the transfer process in order to perceive the same quality. The analysis of the qualitative findings resulted in a framework including six important factors for a successful transfer project. Following factors should be taken in consideration by the company to achieve a successful transfer project: identification of knowledge carriers, set up a transfer core-team, empowering knowledge sharing, the use of a personalized strategy, the development of similar processes and improve the common perception of quality.

  • 64.
    Afifi, S.
    et al.
    Auckland University of Technology, Auckland, New Zealand.
    Gholamhosseini, H.
    Auckland University of Technology, Auckland, New Zealand.
    Sinha, R.
    Auckland University of Technology, Auckland, New Zealand.
    Lindén, Maria
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    A Novel Medical Device for Early Detection of Melanoma2019Inngår i: Studies in Health Technology and Informatics, ISSN 0926-9630, E-ISSN 1879-8365, Vol. 261, s. 122-127Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Melanoma is the deadliest form of skin cancer. Early detection of melanoma is vital, as it helps in decreasing the death rate as well as treatment costs. Dermatologists are using image-based diagnostic tools to assist them in decision-making and detecting melanoma at an early stage. We aim to develop a novel handheld medical scanning device dedicated to early detection of melanoma at the primary healthcare with low cost and high performance. However, developing this particular device is very challenging due to the complicated computations required by the embedded diagnosis system. In this paper, we propose a hardware-friendly design for implementing an embedded system by exploiting the recent hardware advances in reconfigurable computing. The developed embedded system achieved optimized implementation results for the hardware resource utilization, power consumption, detection speed and processing time with high classification accuracy rate using real data for melanoma detection. Consequently, the proposed embedded diagnosis system meets the critical embedded systems constraints, which is capable for integration towards a cost- and energy-efficient medical device for early detection of melanoma.

  • 65.
    Afsar, Atahan
    et al.
    Sabanci University, Istanbul.
    Ulubilge, Tunca
    Sabanci University, Istanbul.
    Çürüklü, Baran
    Mälardalens högskola, Akademin för innovation, design och teknik.
    A biological plausible recurrent model of V1 hypercolumns2011Inngår i: BMC neuroscience (Online), ISSN 1471-2202, E-ISSN 1471-2202, Vol. 12(Suppl 1), nr P48Artikkel i tidsskrift (Fagfellevurdert)
  • 66.
    Afshar, Sara
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Lock-Based Resource Sharing for Real-Time Multiprocessors2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Embedded systems are widely used in the industry and are typically resource constrained, i.e., resources such as processors, I/O devices, shared buffers or shared memory might be limited in the system. Hence, techniques that can enable an efficient usage of processor bandwidths in such systems are of great importance. Locked-based resource sharing protocols are proposed as a solution to overcome resource limitation by allowing the available resources in the system to be safely shared. In recent years, due to a dramatic enhancement in the functionality of systems, a shift from single-core processors to multi-core processors has become inevitable from an industrial perspective to tackle the raised challenges due to increased system complexity. However, the resource sharing protocols are not fully mature for multi-core processors. The two classical multi-core processor resource sharing protocols, spin-based and suspension-based protocols, although providing mutually exclusive access to resources, can introduce long blocking delays to tasks, which may be unacceptable for many industrial applications. In this thesis we enhance the performance of resource sharing protocols for partitioned scheduling, which is the de-facto scheduling standard for industrial real-time multi-core processor systems such as in AUTOSAR, in terms of timing and memory requirements.

     

    A new scheduling approach uses a resource efficient hybrid approach combining both partitioned and global scheduling where the partitioned scheduling is used to schedule the major number of tasks in the system. In such a scheduling approach applications with critical task sets use partitioned scheduling to achieve higher level of predictability. Then the unused bandwidth on each core that is remained from partitioning is used to schedule less critical task sets using global scheduling to achieve higher system utilization. These scheduling schema however lacks a proper resource sharing protocol since the existing protocols designed for partitioned and global scheduling cannot be directly applied due to the complex hybrid structure of these scheduling frameworks. In this thesis we propose a resource sharing solution for such a complex structure. Further, we provide the blocking bounds incurred to tasks under the proposed protocols and enhance the schedulability analysis, which is an essential requirement for real-time systems, with the provided blocking bounds.

  • 67.
    Afshar, Sara
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Lock-Based Resource Sharing in Real-Time Multiprocessor Platforms2014Licentiatavhandling, med artikler (Annet vitenskapelig)
    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.

  • 68.
    Afshar, Sara
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Resource Sharing under Server-based Multiprocessor SchedulingInngår i: 33rd IEEE Real-Time Systems Symposium (RTSS'12), Work-in-Progress (WiP) sessionKonferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper, we investigate a mechanism for handling resource sharing among tasks under a server-based scheduling technique in multiprocessor platforms, which combines partitioned and global scheduling to benefit a better scheduling method compared to conventional techniques.

  • 69.
    Afshar, Sara
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Bril, R. J.
    Technische Universiteit Eindhoven, Eindhoven, Netherlands .
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Flexible spin-lock model for resource sharing in multiprocessor real-time systems2014Inngår i: Proc. IEEE Int. Symp. Ind. Embedded Syst., SIES, 2014, s. 41-51Konferansepaper (Fagfellevurdert)
    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.

  • 70.
    Afshar, Sara
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Bril, Reinder J.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Resource sharing in a hybrid partitioned/global scheduling framework for multiprocessors2015Inngår i: IEEE International Conference on Emerging Technologies and Factory Automation, ETFA, 2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    For resource-constrained embedded real-time systems, resource-efficient approaches are very important. Such an approach is presented in this paper, targeting systems where a critical application is partitioned on a multi-core platform and the remaining capacity on each core is provided to a noncritical application using resource reservation techniques. To exploit the potential parallelism of the non-critical application, global scheduling is used for its constituent tasks. Previously, we enabled intra-application resource sharing for such a framework, i.e. each application has its own dedicated set of resources. In this paper, we enable inter-application resource sharing, in particular between the critical application and the non-critical application. This effectively enables resource sharing in a hybrid partitioned/global scheduling framework on multiprocessors. For resource sharing, we use a spin-based synchronization protocol. We derive blocking bounds and extend existing schedulability analysis for such a system.

  • 71.
    Afshar, Sara
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Bril, Reinder J.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. Technische Universiteit Eindhoven, Eindhoven, Netherlands.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Resource Sharing Under Global Scheduling with Partial Processor Bandwidth2015Inngår i: 2015 10th IEEE International Symposium on Industrial Embedded Systems, SIES 2015 - Proceedings, 2015, s. 195-206Konferansepaper (Fagfellevurdert)
    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.

  • 72.
    Afshar, Sara
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    J. Bril, Reinder
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Per Processor Spin-Lock Priority for Partitioned Multiprocessor Real-Time Systems2014Rapport (Annet vitenskapelig)
    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.

  • 73.
    Afshar, Sara
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    J. Bril, Reinder
    Technische Universiteit Eindhoven, Eindhoven, The Netherlands.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Per Processor Spin-Lock Priority for Partitioned Multiprocessor Real-Time Systems2017Inngår i: Leibniz Transactions on Embedded Systems, ISSN 2199-2002, nr 2Artikkel i tidsskrift (Annet vitenskapelig)
    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.

  • 74.
    Afshar, Sara
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Integrating independently developed real-time applications on a shared multi-core architecture2013Inngår i: ACM SIGBED Review, v. 10, n. 3, 2013, s. 49-56Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The shift towards multi-core platforms has become inevitable from an industry perspective, therefore proper techniques are needed to deal with challenges related to this migration from single core architectures to a multi-core architecture. One of the main concerns for the system developers in this context is the migration of legacy real-time systems to multi-core architectures. To address this concern and to simplify migration, independently developed subsystems are abstracted with an interface, such that when working with multiple independently-developed subsystems to be integrated on a shared platform, one does not need to be aware of information or policies used in other subsystems in order to determine subsystem-level schedulability. Instead schedulability can be checked through their interfaces at the time of integration on a shared multi-core architecture. In this paper we propose a solution for the case where some of the independently-developed subsystems are distributed over more than one processor and we propose an approach to generate interfaces of subsystems that may share mutually exclusive resources.

  • 75.
    Afshar, Sara
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Semi-partitioning under a Blocking-Aware Task Allocation2015Inngår i: Proceedings - Real-Time Systems Symposium, 2015, s. 379-379Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Semi-partitioned scheduling is a resource efficient scheduling approach compared to the conventional multiprocessor scheduling approaches in terms of system utilization and migration overhead. Semi-partitioned scheduling can better utilize processor bandwidth compared to the partitioned scheduling while introducing less overhead compared to the global scheduling. Various techniques have been proposed to schedule tasks in a semi-partitioned environment, however, they have used blockingagnostic allocation mechanisms in presence of resource sharing protocols. Since, the allocation mechanism can highly affect the system schedulability, in this paper we provide a blocking-aware allocation mechanism for semi-partitioned scheduling framework under a suspension-based resource sharing protocol. We have applied new heuristics for sorting the tasks in the algorithm that shows improvements upon system schedulability. Finally, we present our preliminary results.

  • 76.
    Afshar, Sara
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Khalilzad, Nima
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Bril, Reinder J.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. Universiteit Eindhoven, Eindhoven, Netherlands.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Intra-component Resource Sharing on a Virtual Multiprocessor Platform2016Inngår i: ACM SIGBED Review: Special Issue on 8th International Workshop on Compositional Theory and Technology for Real-Time Embedded Systems, 2016, s. 31-32Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Component-based software development facilitates the development process of large and complex software systems. By the advent of multiprocessors, the independently developed components can be integrated on a multi-core platform to achieve an efficient use of system hardware and a decrease in system power consumption and costs. In this paper, we consider a virtual multiprocessor platform where each component can be dynamically allocated to any set of processors of the platform with a maximum concurrency level. Global-EDF is used for intra-component scheduling. The existing analysis for such systems have assumed that tasks are independent. In this paper, we enable intra-component resource sharing for this platform. We investigate using a spin-based resource sharing protocol with the accompanying analysis that extends the existing analysis for independent tasks. We briefly illustrate and evaluate our initial results with an example.

  • 77.
    Afshar, Sara
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Moghaddami Khalilzad, Nima
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nemati, Farhang
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Resource Sharing among Prioritized Real-Time Applications on Multiprocessors2015Inngår i: ACM SIGBED Review - Special Issue on the 6th International Workshop on Compositional Theory and Technology for Real-Time Embedded Systems Homepage archiveVolume 12 Issue 1, 2015, s. 46-55Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper, we propose a new protocol for handling resource sharing among prioritized real-time applications composed on a multiprocessor platform. We propose an optimal priority assignment algorithm which assigns unique priorities to the applications based on information in their interfaces. We have performed experimental evaluations to compare the proposed protocol (called MSOS-Priority) to the current state of the art locking protocols under multiprocessor partitioned scheduling, i.e., MPCP, MSRP, FMLP, MSOS, and OMLP. The valuations show that MSOS-Priority mostly performs significantly better than alternative approaches.

  • 78.
    Afshar, Sara
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Nemati, Farhang
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Resource Sharing under Multiprocessor Semi-Partitioned Scheduling2012Inngår i: 18th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications (RTCSA'12), 2012, s. 290-299Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Semi-partitioned scheduling has become the subject of recent interest for multiprocessors due to better utilization results, compared to conventional global and partitioned scheduling algorithms. Under semi-partitioned scheduling, a major group of tasks are assigned to fixed processors while a low number of tasks are allocated to more than one processor. Various task assigning techniques have recently been proposed in a semi-partitioned environment. However, a synchronization mechanism for resource sharing among tasks in semi-partitioned scheduling has not yet been investigated. In this paper we propose and evaluate two methods for handling resource sharing under semi-partitioned scheduling in multiprocessor platforms. The main challenge addressed in this paper is to serve the resource requests of tasks that are assigned to different processors.

  • 79.
    Afshar, Sara
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Nemati, Farhang
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Towards Resource Sharing under Multiprocessor Semi-Partitioned Scheduling2012Inngår i: 7th IEEE International Symposium on Industrial Embedded Systems (SIES'12): Conference Proceedings, 2012, s. 315-318Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Semi-partitioned scheduling has been the subject of recent interest, compared with conventional global and partitioned scheduling algorithms for multiprocessors, due to better utilization results. In semi-partitioned scheduling most tasks are assigned to fixed processors while a low number of tasks are split up and allocated to different processors. Various techniques have recently been proposed to assign tasks in a semi-partitioned environment. However, an appropriate resource sharing mechanism for handling the resource requests between tasks in semi-partitioned scheduling has not yet been investigated. In this paper we propose two methods for handling resource sharing under semi-partitioned scheduling in multiprocessor platforms. The main challenge is to handle the resource requests of tasks that are split over multiple processors.

  • 80.
    Afshar, Sara Zargari
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Real-time and offline evaluation of myoelectric pattern recognition for upper limb prosthesis controlManuskript (preprint) (Annet vitenskapelig)
  • 81.
    Afshar, Sara Zargari
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    J. Bril, Reinder
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. Technische Universiteit Eindhoven, Eindhoven, Netherlands.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    An optimal spin-lock priority assignment algorithm for real-time multi-core systems2017Inngår i: The 23th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications RTCSA'17, 2017, artikkel-id 8046310Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Support for exclusive access to shared (global) resources is instrumental in the context of embedded real-time multi-core systems, and mechanisms for achieving such access must be deterministic and efficient. There exist two traditional approaches for multiprocessors when a task requests a global resource that is locked by a task on a remote core: a spin-based approach, i.e. non-preemptive busy waiting for the resource to become available, and a suspension-based approach, i.e. the task relinquishes the processor. A suspension-based approach can be viewed as a spin-based approach where the lowest priority on a core is used during spinning, similar to a non-preemptive spin-based approach where the highest priority on a core is used. By taking such a view, we previously provided a general model for spinning, where any arbitrary priority can be used for spinning, i.e. from the lowest to the highest priority on a core. Targeting partitioned fixed-priority preemptive scheduled multiprocessors and spin-based approaches that use a fixed priority for spinning per core for all tasks, we aim at increasing the schedulability of multiprocessor systems by using the spin-lock priority per core as parameter. In this paper, we present (i) a generalization of the traditional worst-case response-time analysis for non-preemptive spin-based approaches addressing an arbitrary but fixed spin-lock priority per core, (ii) an optimal spin-lock priority assignment (OSPA) algorithm per core, i.e. an algorithm that will find a fixed spin-lock priority per core that will make the system schedulable, whenever such an assignment exists and, (iii) comparative evaluations of the OSPA algorithm with the spin-based and suspension-based approaches where OSPA showed up to 38% improvement compared to both approaches.

  • 82.
    Afshar, Sara Zargari
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Koroorian, Fereidon
    ABB, Västerås, Sweden.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Granlund, Anna
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Investigating Alternatives for System Architectures to Enhance Discrete Manufacturing2019Inngår i: International Journal of Distributed Sensor Networks, ISSN 1550-1329, E-ISSN 1550-1477, Vol. 15, nr 8, artikkel-id 1550147719868668Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This article investigates the possibility of advancing discrete manufacturing using system architectures that are developed for Collaborative Process Automation Systems. Collaborative Process Automation System is a technology that has the potential to achieve production excellence for process industry. However, not much attention has been paid on using the architectures based on Collaborative Process Automation Systems for discrete manufacturing domains. In this article, we propose a base architecture consisting of three layers, and we discuss various alternatives to make the communications among the layers. We consider legacy components in the proposal, in contrast to most of the related works. In order to show the practicality of the proposed alternatives, we present an example that has been implemented in an ongoing project at ABB Robotics in Sweden.

  • 83.
    Afshari, Houtan
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Finding optimum batch sizes for a high mix, low volume surface mount technology line2014Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
  • 84.
    Afsharmazayejani, R.
    et al.
    Shahid Bahonar University of Kerman, Kerman, Iran.
    Yazdanpanah, F.
    Vali-e-Asr University, Rafsanjan, Iran.
    Rezaei, A.
    Northwestern University, Evanston, United States.
    Alaei, M.
    Vali-e-Asr University, Rafsanjan, Iran.
    Daneshtalab, Masoud
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    HoneyWiN: Novel honeycomb-based wireless NoC architecture in many-core era2018Inngår i: Lecture Notes in Computer Science, ISSN 0302-9743, E-ISSN 1611-3349, Vol. 10824 LNCS, s. 304-316Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Although NoC-based systems with many cores are commercially available, their multi-hop nature has become a bottleneck on scaling performance and energy consumption parameters. Alternatively, hybrid wireless NoC provides a postern by exploiting single-hop express links for long-distance communications. Also, there is a common wisdom that grid-like mesh is the most stable topology in conventional designs. That is why almost all of the emerging architectures had been relying on this topology as well. In this paper, first we challenge the efficiency of the grid-like mesh in emerging systems. Then, we propose HoneyWiN, a hybrid reconfigurable wireless NoC architecture that relies on the honeycomb topology. The simulation results show that on average HoneyWiN saves 17% of energy consumption while increases the network throughput by 10% compared to its wireless mesh counterpart. 

  • 85.
    Afzal, Wasif
    Mälardalens högskola, Akademin för innovation, design och teknik. Embedded Systems.
    Search-based approaches to software fault prediction and software testing2009Licentiatavhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    Software verification and validation activities are essential for software quality but also constitute a large part of software development costs. Therefore efficient and cost effective software verification and validation activities are both a priority and a necessity considering the pressure to decrease time-to-market and intense competition faced by many, if not all, companies today. It is then perhaps not unexpected that decisions related to software quality, when to stop testing, testing schedule and testing resource allocation needs to be as accurate as possible. This thesis investigates the application of search-based techniques within two activities of software verification and validation: Software fault prediction and software testing for non-functional system properties. Software fault prediction modeling can provide support for making important decisions as outlined above. In this thesis we empirically evaluate symbolic regression using genetic programming (a search-based technique) as a potential method for software fault predictions. Using data sets from both industrial and open-source software, the strengths and weaknesses of applying symbolic regression in genetic programming are evaluated against competitive techniques. In addition to software fault prediction this thesis also consolidates available research into predictive modeling of other attributes by applying symbolic regression in genetic programming, thus presenting a broader perspective. As an extension to the application of search-based techniques within software verification and validation this thesis further investigates the extent of application of search-based techniques for testing non-functional system properties. Based on the research findings in this thesis it can be concluded that applying symbolic regression in genetic programming may be a viable technique for software fault prediction. We additionally seek literature evidence where other search-based techniques are applied for testing of non-functional system properties, hence contributing towards the growing application of search-based techniques in diverse activities within software verification and validation.

  • 86.
    Afzal, Wasif
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. Bahria University, Islamabad, Pakistan.
    Alone, Snehal
    Chalmers University of Technology, Sweden.
    Glocksien, Kerstin
    Chalmers University of Technology, Sweden.
    Torkar, Richard
    Chalmers University of Technology, Sweden.
    Software Test Process Improvement Approaches: A Systematic Literature Review and an Industrial Case Study2016Inngår i: Journal of Systems and Software JSS, ISSN 0164-1212, Vol. 111, s. 1-33Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Software test process improvement (STPI) approaches are frameworks that guide software development organizations to improve their software testing process. We have identified existing STPI approaches and their characteristics (such as completeness of development, availability of information and assessment instruments, and domain limitations of the approaches) using a systematic literature review (SLR). Furthermore, two selected approaches (TPI NEXT and TMMi) are evaluated with respect to their content and assessment results in industry. As a result of this study, we have identified 18 STPI approaches and their characteristics. A detailed comparison of the content of TPI NEXT and TMMi is done. We found that many of the STPI approaches do not provide sufficient information or the approaches do not include assessment instruments. This makes it difficult to apply many approaches in industry. Greater similarities were found between TPI NEXT and TMMi and fewer differences. We conclude that numerous STPI approaches are available but not all are generally applicable for industry. One major difference between available approaches is their model representation. Even though the applied approaches generally show strong similarities, differences in the assessment results arise due to their different model representations.

  • 87.
    Afzal, Wasif
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    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 systems2018Inngår i: Microprocessors and microsystems, ISSN 0141-9331, E-ISSN 1872-9436, Vol. 61, s. 86-95Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 88.
    Afzal, Wasif
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Bruneliere, Hugo
    AtlanMod Team, Inria, France.
    Di Ruscio, Davide
    Univ. of L'Aquila, L'Aquila, Italy.
    Sadovykh, Andrey
    Softeam, France.
    Mazzini, Silvia
    Intecs, Italy.
    Cariou, Eric
    Univ. de Pau et des Pays de l'Adour, Pau, France.
    Truscan, Dragos
    Åbo Akademi Univ., Turku, Finland.
    Cabot, Jordi
    Jordi Cabot ICREA, Barcelona, Spain.
    Field, Daniel
    ATOS, Madrid, Spain.
    Pomante, Luigi
    Univ. of L'Aquila, L'Aquila, Italy.
    Smrz, Pavel
    Brno Univ. of Technol., Brno, Czech Republic.
    The MegaM@Rt2 ECSEL Project: MegaModelling at Runtime — Scalable Model-Based Framework for Continuous Development and Runtime Validation of Complex Systems2017Inngår i: The 2017 Euromicro Conference on Digital System Design DSD'17, 2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A major challenge for the European electronic industry is to enhance productivity while reducing costs and ensuring quality in development, integration and maintenance. Model-Driven Engineering (MDE) principles and techniques have already shown promising capabilities but still need to scale 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-time phases (design time and runtime) is another challenge facing scalability of MDE. This paper presents an overview of the ECSEL 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 & continuous development, 2) related runtime analysis and 3) global model & traceability management, respectively. The diverse industrial use cases (covering domains such as aeronautics, railway, construction and telecommunications) will integrate and apply such a framework that shall demonstrate the validation of the MegaM@Rt2 solution.

  • 89.
    Afzal, Wasif
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    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
    Mälardalens högskola.
    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 track2018Inngår i: Proceedings / International Conference of Software Engineering, ISSN 0270-5257, E-ISSN 1558-1225, Vol. Part F137351Artikkel i tidsskrift (Fagfellevurdert)
  • 90.
    Afzal, Wasif
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    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 testing2015Inngår i: Journal of Empirical Software Engineering, ISSN 1382-3256, E-ISSN 1573-7616, Vol. 20, nr 3, s. 844-878Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 91.
    Afzal, Wasif
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik. Blekinge Institute of Technology.
    Torkar, Richard
    Blekinge Institute of Technology.
    A comparative evaluation of using genetic programming for predicting fault count data2008Inngår i: Proceedings - The 3rd International Conference on Software Engineering Advances, ICSEA 2008, Includes ENTISY 2008: International Workshop on Enterprise Information Systems, 2008, s. 407-414Konferansepaper (Fagfellevurdert)
    Abstract [en]

    There have been a number of software reliability growth models (SRGMs) proposed in literature. Due to several reasons, such as violation of models’ assumptions and complexity of models, the practitioners face difficulties in knowing which models to apply in practice. This paper presents a comparative evaluation of traditional models and use of genetic programming (GP) for modeling software reliability growth based on weekly fault count data of three different industrial projects. The motivation of using a GP approach is its ability to evolve a model based entirely on prior data without the need of making underlying assumptions. The results show the strengths of using GP for predicting fault count data.

  • 92.
    Afzal, Wasif
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. 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 prediction2016Inngår i: Computational Intelligence and Quantitative Software Engineering / [ed] Witold Pedrycz, Giancarlo Succi and Alberto Sillitti, Springer-Verlag , 2016, s. 33-58Kapittel i bok, del av antologi (Annet vitenskapelig)
    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.

  • 93.
    Afzal, Wasif
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik. Blekinge Institute of Technology.
    Torkar, Richard
    Blekinge Institute of Technology.
    Feldt, Robert
    Blekinge Institute of Technology.
    Wikstrand, Greger
    KnowIT YAHM Sweden AB.
    Search-based prediction of fault-slip-through in large software projects2010Inngår i: Proceedings - 2nd International Symposium on Search Based Software Engineering, SSBSE 2010, 2010, s. 79-88Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A large percentage of the cost of rework can be avoided by ?nding more faults earlier in a software testing process. Therefore, determination of which software testing phases to focus improvements work on, has considerable industrial interest. This paper evaluates the use of ?ve different techniques, namely particle swarm optimization based arti?cial neural networks (PSO-ANN), arti?cial immune recognition systems (AIRS), gene expression programming (GEP), genetic programming (GP) and multiple regression (MR), for predicting the number of faults slipping through unit, function, integration and system testing phases. The objective is to quantify improvement potential in different testing phases by striving towards ?nding the right faults in the right phase. We have conducted an empirical study of two large projects from a telecommunication company developing mobile platforms and wireless semiconductors. The results are compared using simple residuals, goodness of ?t and absolute relative error measures. They indicate that the four search-based techniques (PSOANN, AIRS, GEP, GP) perform better than multiple regression for predicting the fault-slip-through for each of the four testing phases. At the unit and function testing phases, AIRS and PSO-ANN performed better while GP performed better at integration and system testing phases. The study concludes that a variety of search-based techniques are applicable for predicting the improvement potential in different testing phases with GP showing more consistent performance across two of the four test phases.

  • 94.
    Agerskans, Natalie
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Ergonomisk kartläggning av internt logistikflöde - Med förbättringsförslag: En fallstudie genomförd på ett företag2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Syftet: Syftet med denna studie är att kartlägga belastningsergonomiska risker i ett framtida internt logistikflöde, samt att ge förslag på hur dessa risker kan undvikas genom tillämpning av LEAN metodik och en ny logistiklösning. Följande frågeställningar har ställts för att identifiera orsaker till problem och förbättringsmöjligheter:

    1)    Vilka arbetsmoment i det studerade logistikflödet leder till ergonomiska risker?

    2)    Hur kan fallstudieföretaget införa LEAN metodik för att uppnå bättre ergonomi vid materialhantering?

    3)    Hur kan en ny generell och mer ergonomisk logistiklösning för materialhantering se ut på fallstudieföretaget?

    Metod: Studien har genomförts baserat på en fallstudie på ett industriföretag. Data har samlats in genom intervjuer och observationer på fallstudieföretaget, studiebesök på två andra industriföretag samt genom en litteraturstudie. För att identifiera och bedöma olika ergonomiska risker har verktyget RAMP tillämpats.

    Studiens resultat: Studien resulterade i en ergonomisk kartläggning för ett utvalt internt logistikflöde med förslag på hur bättre ergonomi kan uppnås i fallstudieföretagets material-hantering. Den ergonomiska kartläggningen påvisade att flera arbetsmoment innebär en ökad risk för att personalen utvecklar belastningsbesvär. Många tunga lyft, skjuta- och dra arbete samt olämpliga arbetsställningar visades ha störst negativ inverkan på ergonomin. För att minska dessa risker utan större förändringar av nuvarande fabrikslayout och befintligt arbetsflöde kan bland annat arbetsrotation, olika hjälpmedel och modifieringar av teknisk utrustning införas. Förslag presenteras också på hur en ny och mer ergonomisk materialhanteringslösning kan se ut på fallstudieföretaget genom införande av en omplockningsstation och en supermarket. Även ett förslaget ramverk presenteras för hur fallstudieföretaget kan arbeta genom LEAN-metodik i syfte att uppnå en bättre ergonomi i materialhanteringen.

    Slutsats: Den ergonomiska kartläggningen indikerade att förbättringsåtgärder krävs för att personal inte ska riskera att utveckla belastningsbesvär och förslag har tagits fram för hur den ergonomiska situationen kan förbättras.

    Rekommendationer: Fallstudieföretaget rekommenderas att vidta åtgärder för de ergonomiska risker som har identifierats. Innan de föreslagna förbättringarna fullföljs krävs vidare studier för att utvärdera förbättringsförslagen ur andra än ergonomiska aspekter samt genomförande av RAMP-analys. Fallstudieföretaget rekommenderas även att undersöka möjligheten att införa det föreslagna LEAN-ramverket i syfte att skapa förutsättningar för en god ergonomisk situation.

    Nyckelord: Belastningsergonomi, RAMP, Omplockningsstation, Arbetsmiljö, Intern logistik, Materialhantering

  • 95.
    Agha Jafari Wolde, Bahareh
    Mälardalens högskola, Akademin för innovation, design och teknik.
    A systematic Mapping study of ADAS and Autonomous Driving2019Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Nowadays, autonomous driving revolution is getting closer to reality. To achieve the Autonomous driving the first step is to develop the Advanced Driver Assistance System (ADAS). Driver-assistance systems are one of the fastest-growing segments in automotive electronics since already there are many forms of ADAS available. To investigate state of art of development of ADAS towards Autonomous Driving, we develop Systematic Mapping Study (SMS). SMS methodology is used to collect, classify, and analyze the relevant publications. A classification is introduced based on the developments carried out in ADAS towards Autonomous driving. According to SMS methodology, we identified 894 relevant publications about ADAS and its developmental journey toward Autonomous Driving completed from 2012 to 2016. We classify the area of our research under three classifications: technical classifications, research types and research contributions. The related publications are classified under thirty-three technical classifications. This thesis sheds light on a better understanding of the achievements and shortcomings in this area. By evaluating collected results, we answer our seven research questions. The result specifies that most of the publications belong to the Models and Solution Proposal from the research type and contribution. The least number of the publications belong to the Automated…Autonomous driving from the technical classification which indicated the lack of publications in this area. 

  • 96.
    Aghaeinezhadfirouzja, S.
    et al.
    Department of Electronics Engineering, Shanghai Jiao Tong University, Shanghai, China.
    Liu, H.
    Department of Electronics Engineering, Shanghai Jiao Tong University, Shanghai, China.
    Balador, Ali
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. RISE SICS Västerås, Sweden.
    Practical 3-D beam pattern based channel modeling for multi-polarized massive MIMO systems2018Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 18, nr 4, artikkel-id 1186Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper, a practical non-stationary three-dimensional (3-D) channel models for massive multiple-input multiple-output (MIMO) systems, considering beam patterns for different antenna elements, is proposed. The beam patterns using dipole antenna elements with different phase excitation toward the different direction of travels (DoTs) contributes various correlation weights for rays related towards/from the cluster, thus providing different elevation angle of arrivals (EAoAs) and elevation angle of departures (EAoDs) for each antenna element. These include the movements of the user that makes our channel to be a non-stationary model of clusters at the receiver (RX) on both the time and array axes. In addition, their impacts on 3-D massive MIMO channels are investigated via statistical properties including received spatial correlation. Additionally, the impact of elevation/azimuth angles of arrival on received spatial correlation is discussed. Furthermore, experimental validation of the proposed 3-D channel models on azimuth and elevation angles of the polarized antenna are specifically evaluated and compared through simulations. The proposed 3-D generic models are verified using relevant measurement data.

  • 97.
    Aglianò, Simone
    et al.
    University of Catania, Catania, Italy.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Lo Bello, Lucia
    University of Catania, Catania, Italy.
    Resource Management and Control in Virtualized SDN Networks2018Inngår i: CSI International Symposium on Real-Time and Embedded Systems and Technologies REST'18, 2018, s. 47-53Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Software defined networking and network virtual-ization are widely considered promising techniques for reducing the complexity of network management in many contexts that require high Quality of Service (QoS) and the support for heterogeneous architectures. In this paper we address a network architecture, here called a virtualized SDN network, that combines the benefits of SDN and virtualization. To cope with the demand for efficiently sharing a platform among several services, here a resource management mechanism to reserve and control network resources among various services in the virtualized SDN networks is proposed. The mechanism is implemented on an SDN controller and a set of experiments show the effectiveness of the proposed approach.

  • 98.
    Agocs, Mathias
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Analys av godssorteringen på DHL Freight AB: En fallstudie om logistik2011Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Sammanfattning

    Det här examensarbetet har genomförts på DHL Freight AB i Eskilstuna som transporterar gods över hela Sverige. Där målsättningen varit att analysera den nuvarande sorteringsprocessen, identifiera bristerna runt sorteringsprocesserna och därefter presentera eventuella förbättringsförlag.

    De metoder som har använts för att utföra examensarbetet är följande. Resultatet grundar sig på den information som har införskaffats via observationer och intervjuer med personalen som är delaktiga i sorteringsprocessen samt olika litteraturstudier.

    De mest tongivande teorierna som examensarbetet utgått från och som författaren har genomgående haft i åtanke är logistik, distribution, Lean Produktion, kvalitet och processer.

    Analysen som utfördes resulterade i att ett antal brister som finns i sorteringsprocessen som kunde identifieras. De här bristerna bidrog till att komplikationer uppstod vid sorteringen av gods på DHL Freight AB. Några exempel på brister som identifierats är att efter godset har hanterats sker inte någon kvalitetssäkring innan godset lämnar terminalen. Dessutom är de resurser som finns idag inte så uppdaterade arbetssätten har inte ändrats eller förbättras på länge. Som till exempel förenkling av kodboken och en mycket tydligare platsning i zonerna så att inte godset ställs på fel plats. Ytterligare brister som kunde identifieras var att den mänskliga faktorn som spelar en stor roll i sorteringen av gods. Att man inte är tillräckligt uppmärksam när man kodar, hanterar eller platsar godset. Man är inte motiverad eller engagerad till att godset ska gå rätt till 100 procent eller så handlar det om att metoderna de använder för att hantera godset är otillräckliga.

    De förbättringsförslag som presenteras i den här rapporten innefattar förändringar som kan leda till att sorteringsprocessen på DHL Freight AB, men även i hela försörjningskedjan, blir mer kontrollerad och exakt jämfört med dagens situation. Förutom en bättre sorterings statistik som uppstår på DHL Freight AB vid sortering av gods, kan dessa förändringar även bidra till kostnadsbesparingar i form av energikostnader och personalkostnader hos DHL Freight i Eskilstuna

  • 99.
    Ahlberg, Carl
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Embedded high-resolution stereo-vision of high frame-rate and low latency through FPGA-acceleration2020Doktoravhandling, med artikler (Annet vitenskapelig)
    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.

  • 100.
    Ahlberg, Carl
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Asplund, Lars
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Campeanu, Gabriel
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Ciccozzi, Federico
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Ekstrand, Fredrik
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Ekström, Mikael
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Feljan, Juraj
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Gustavsson, Andreas
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Sentilles, Séverine
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Svogor, Ivan
    FOI, University of Zagreb.
    Segerblad, Emil
    The Black Pearl: An Autonomous Underwater Vehicle2013Rapport (Annet vitenskapelig)
    Abstract [en]

    The Black Pearl is a custom made autonomous underwater vehicle developed at Mälardalen University, Sweden. It is built in a modular fashion, including its mechanics, electronics and software. After a successful participation at the RoboSub competition in 2012 and winning the prize for best craftsmanship, this year we made minor improvements to the hardware, while the focus of the robot's evolution shifted to the software part. In this paper we give an overview of how the Black Pearl is built, both from the hardware and software point of view.

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