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  • 251. Ahlgren, B.
    et al.
    Hidell, Markus
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Network Systems Laboratory (NS Lab).
    Ngai, E. C. -H
    Internet of Things for Smart Cities: Interoperability and Open Data2016In: IEEE Internet Computing, ISSN 1089-7801, E-ISSN 1941-0131, Vol. 20, no 6, p. 52-56, article id 7781549Article in journal (Refereed)
    Abstract [en]

    The Internet of Things (IoT) has become a promising technology for addressing societal challenges by connecting smart devices and leveraging Big Data analytics to create smart cities worldwide. As the IoT scales up, it's important to provide interoperability among different devices. Yet current simple standard protocols lack sufficient openness and interoperability. IoT for smart cities needs to guarantee the accessibility of open data and cloud services to allow industries and citizens to develop new services and applications. Here, the authors provide a case study of the GreenIoT platform in Uppsala, Sweden, to demonstrate the idea of interoperability and open data for smart cities.

  • 252.
    Ahlgren, Bengt
    et al.
    RISE, Swedish ICT, SICS, Decisions, Networks and Analytics lab.
    Hidell, Markus
    Ngai, Edith
    Internet of Things for Smart Cities: Interoperability and Open Data2016In: IEEE Internet Computing, ISSN 1089-7801, E-ISSN 1941-0131, p. 52-56Article in journal (Refereed)
    Abstract [en]

    The Internet of Things (IoT) for smart cities needs accessible open data and open systems, so that industries and citizens can develop new services and applications. As an example, the authors provide a case study of the GreenIoT platform in Uppsala, Sweden.

  • 253.
    Ahlgren, Bengt
    et al.
    RISE, Swedish ICT, SICS, Decisions, Networks and Analytics lab.
    Hurtig, Per
    Abrahamsson, Henrik
    RISE, Swedish ICT, SICS, Decisions, Networks and Analytics lab.
    Grinnemo, Karl-Johan
    Brunstrom, Anna
    Are MIRCC and Rate-based Congestion Control in ICN READY for Variable Link Capacity?2017Conference paper (Refereed)
    Abstract [en]

    Information-centric networking~(ICN) has been introduced as a potential future networking architecture. ICN promises an architecture that makes information independent from location, application, storage, and transportation. Still, it is not without challenges. Notably, there are several outstanding issues regarding congestion control: Since ICN is more or less oblivious to the location of information, it opens up for a single application flow to have several sources, something which blurs the notion of transport flows, and makes it very difficult to employ traditional end-to-end congestion control schemes in these networks. Instead, ICN networks often make use of hop-by-hop congestion control schemes. However, these schemes are also tainted with problems, e.g., several of the proposed ICN congestion controls assume fixed link capacities that are known beforehand. Since this seldom is the case, this paper evaluates the consequences in terms of latency, throughput, and link usage, variable link capacities have on a hop-by-hop congestion control scheme, such as the one employed by the Multipath-aware ICN Rate-based Congestion Control~(MIRCC). The evaluation was carried out in the OMNeT++ simulator, and demonstrates how seemingly small variations in link capacity significantly deteriorate both latency and throughput, and often result in inefficient network link usage.

  • 254.
    Ahlgren, Bengt
    et al.
    RISE - Research Institutes of Sweden, ICT, SICS.
    Hurtig, Per
    Karlstad University, Sweden.
    Abrahamsson, Henrik
    RISE - Research Institutes of Sweden, ICT, SICS.
    Grinnemo, Karl-Johan
    Karlstad University, Sweden.
    Brunstrom, Anna
    Karlstad University, Sweden.
    ICN Congestion Control for Wireless Links2018Conference paper (Refereed)
    Abstract [en]

    Information-centric networking (ICN) with its design around named-based forwarding and in-network caching holds great promises to become a key architecture for the future Internet. Still, despite its attractiveness, there are many open questions that need to be answered before wireless ICN becomes a reality, not least about its congestion control: Many of the proposed hop-by-hop congestion control schemes assume a fixed and known link capacity, something that rarely – if ever – holds true for wireless links. As a first step, this paper demonstrates that although these congestion control schemes are able to fairly well utilise the available wireless link capacity, they greatly fail to keep the link delay down. In fact, they essentially offer the same link delay as in the case with no hop-by-hop, only end-to-end, congestion control. Secondly, the paper shows that by complementing these congestion control schemes with an easy-to-implement, packet-train link estimator, we reduce the link delay to a level significantly lower than what is obtained with only end-to-end congestion control, while still being able to keep the link utilisation at a high level.

  • 255.
    Ahlgren, Bengt
    et al.
    RISE, Swedish ICT, SICS, Decisions, Networks and Analytics lab.
    Lindgren, Anders
    RISE, Swedish ICT, SICS, Decisions, Networks and Analytics lab.
    Wu, Yanqiu
    Demo: Experimental Feasibility Study of CCN-lite on Contiki Motes for IoT Data Streams2016In: ICN 2016: 3rd ACM Conference on Information-Centric Networking, 2016Conference paper (Refereed)
  • 256.
    Ahlgren, Hannes
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering.
    Graph visualization with OpenGL2005Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Vizz3D is a 3D graphics code analysis tool, developed at Växjö University that optionally can use Java3D or OpenGL. However, initially Java3D was the only programming interface used. No other version was considered. Therefore the applications structure was built with the Java3D way of thought in mind. But code visualization with 3D graphics can be a demanding task for the computers processor and its graphics hardware and Java3D is known to be somewhat inefficient. So an OpenGL version was introduced.

    This thesis reflects on the work restructuring the application’s code to fit both versions within Vizz3D in a structured and object-oriented way. The thesis shows the efforts to be taken to make an existing ever evolving tool easily extendible to other API’s. Additional aspects of OpenGL specific implementations are discussed throughout the thesis.

  • 257.
    Ahlgren, Joel
    et al.
    KTH, School of Computer Science and Communication (CSC).
    Mikkola, Mattias
    KTH, School of Computer Science and Communication (CSC).
    Net Voting – Designing an Online Voting System.2011Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    We are currently in a time where old routines and ways are being converted to more easily accessible, digital ways. You can perform your bank errands and interact with authorities through the Internet. While many of our societies functions already have undergone this transformation, our elections are still very manual. In our report we present what we think are the biggest obstacles to implementing a net voting system in Sweden, how to solve these issues and present a system which we feel would be a good start to designing The Ultimate Net Voting System. We touch upon areas like authenticating voters, protecting their right to anonymous voting in sending and storing votes and ways to protect against attacks against this system. In the end, we present an abstract level of a system design which could begin to fulfill all requirements to make net voting a feasible solution.

  • 258.
    Ahlgren, Joel
    et al.
    KTH, School of Computer Science and Communication (CSC), Media technology and interaction design.
    Mikkola, Mattias
    KTH, School of Computer Science and Communication (CSC), Media technology and interaction design.
    Net Voting – Designing an Online Voting System.2011Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    We are currently in a time where old routines and ways are being converted to more easily accessible, digital ways. You can perform your bank errands and interact with authorities through the Internet. While many of our societies functions already have undergone this transformation, our elections are still very manual. In our report we present what we think are the biggest obstacles to implementing a net voting system in Sweden, how to solve these issues and present a system which we feel would be a good start to designing The Ultimate Net Voting System. We touch upon areas like authenticating voters, protecting their right to anonymous voting in sending and storing votes and ways to protect against attacks against this system. In the end, we present an abstract level of a system design which could begin to fulfill all requirements to make net voting a feasible solution.

  • 259.
    Ahlgren, Johan
    et al.
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Karlsson, Robert
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    En studie av inbyggda brandväggar: Microsoft XP och Red Hat Linux2003Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Detta kandidatarbete utreder hur väl två operativsystems inbyggda brandväggar fungerar i symbios med en användares vanligaste tjänsteutnyttjande på Internet, samt att se hur likartade de är i sitt skydd från hot. De två operativsystemen som vi utgick ifrån var Microsoft Windows XP samt Red Hat Linux 8.0. Den hypotes vi arbetat kring lyder enligt följande: De två inbyggda brandväggarna är i stort likartade rörande skydd från hot på Internet och uppfyller användarnas tjänsteutnyttjande. De metoder vi använt, för att svara på vår frågeställning, har delats upp i ett funktionalitetstest och ett säkerhetstest. I funktionalitetstestet provades de vanligaste Internettjänsterna med den inbyggda brandväggen och ifall det uppstod några komplikationer eller ej. De två inbyggda brandväggarna genom gick i säkerhetstestet skannings- och svaghetskontroll via ett flertal verktyg. Genom resultatet kan vi konstatera att de inbyggda brandväggarna klarar av de vanligaste tjänsterna på Internet, men att en skillnad föreligger hos dem vad gäller exponeringen ut mot Internet. Windows XP ligger helt osynligt utåt, medan Red Hats inbyggda brandvägg avslöjar en mängd information om värddatorn, som kan komma att användas i illvilliga syften. Slutsatsen blev att vi avslutningsvis falsifierade vår hypotes då de två inbyggda brandväggarna ej var jämlika i sitt skydd mot yttre hot på Internet.

  • 260.
    Ahlgren, Linus
    University of Skövde, Department of Computer Science.
    En objektorienterad, semistrukturerad databas för lagring av proteininformation2001Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    Under det senaste årtiondet har molekylärbiologin genomgått stora förändringar. Genom utvecklingen av tekniker för DNA-sekvensiering har man kunnat utforska stora mängder information. Denna information lagras i biodatabaser som i många fall är länkade med varandra för att ge användaren ett bredare sökfält. SWISS-PROT är ett exempel på en sådan biodatabas som lagrar proteininformation.

    Användare som har mindre kunskap om databasens uppbyggnad och unika identifierare kan dock stöta på problem i form av en mängd sökresultat, där endast en mindre del är intressanta för användaren. Missförstånd och tvetydigheter kan också uppstå i länkade biodatabaser, då databaserna har olika uppbyggnad och definitioner på olika "byggstenar" i databasen.

    Arbetet i denna rapport ska därför fokusera på att skapa en databas för molekylärbiologidata som tar hand om dessa problem. För att kunna åstadkomma detta ska ett databashanteringssystem som har funktionaliteter som erbjuder lösningar till dessa problem användas. Den data, i form av proteininformation, som ska lagras hämtas från en SWISS-PROT-domän. I arbetet kommer databashanteringssystemet Lore att användas.

  • 261. Ahlgren, Per
    et al.
    Grönqvist, Leif
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering.
    Evaluation of retrieval effectiveness with incomplete relevance data: theoretical and experimental comparison of three measures2007In: International Journal of Information Processing & Management, Vol. In press, p. 14-Article in journal (Refereed)
    Abstract [en]

    The main reason for this work is to find an appropriate way to include multi-word units in a latent semantic vector model. This would be of great use since these models normally are defined in terms of words, which makes it impossible to search for many types of multi-word units when the model is used in information retrieval tasks. The paper presents a Swedish evaluation set based on synonym tests and an evaluation of vector models trained with different corpora and parameter settings, including a rather naive way to add bi- and trigrams to the models. The best results in the evaluation is actually obtained with both bi- and trigrams added. Our hope is that the results in a forthcoming evaluation in the document retrieval context, which is an important application for these models, still will be at least as good with the bi- and trigrams are added, as without.

  • 262. Ahlgren, Per
    et al.
    Grönqvist, Leif
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering.
    Measuring retrieval effectiveness with incomplete relevance data2006In: Current Research in Information Sciences and Technologies: Multidisciplinary approaches to global information systems (InSciT2006 proceedings), Open Institute of Knowledge , 2006, p. 74-78Conference paper (Refereed)
  • 263. Ahlgren, Per
    et al.
    Grönqvist, Leif
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering.
    Retrieval evaluation with incomplete relevance data: A comparative study of three measures (poster abstract)2006In: Proceedings of the 15th ACM International Conference on Information and Knowledge Management (CIKM), ACM Press, New York, NY, USA , 2006, p. 872-873Conference paper (Refereed)
  • 264.
    Ahlin, Daniel
    et al.
    Växjö University.
    Jartelius, Martin
    Växjö University.
    Tingdahl, Johanna
    Växjö University.
    Proxyserver för passiv informationssökning2005Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In today’s society the average person is flooded by information from everywhere. This is in particular the case when using the Internet; consider for a moment the fact that a decent search engine at this moment scans 8 058 million homepages. For a user that repeatedly comes back to the same site, the case is often that they know what they are looking for. The problem is to isolate the important information from all the other information embedding it.

    We would like to state that we have found one possible solution to this problem, where the user himself can define what information he is looking for at a specific server, then scan the server when visiting it with his browser. The information is then saved and made easily accessible to the user, independent of what system he is using.

    Our solution is based on a proxy-server, through which the user makes his connections. The server is configurable as to what information to scan for and where, as well as in what format, the data should be saved. Our method with an independent proxyserver is not as efficient as including this support into a browser, but it is enough to give proof of the concept. For high-speed connections to a server on the same network as the user, it might be possible for a user to notice that it is slowing down the connection, but it’s a matter of fractions of a second, and surfing under normal conditions the user is very unlikely to be bothered by the proxy. The actual loss in performance is the time required to make a second TCP-connection for each call, as well as a slight loss of efficiency due to Java’s thread synchronization.

  • 265. Ahlkrona, Josefin
    et al.
    Lötstedt, Per
    Kirchner, Nina
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Zwinger, Thomas
    Dynamically coupling the non-linear Stokes equations with the shallow ice approximation in glaciology: Description and first applications of the ISCAL method2016In: Journal of Computational Physics, ISSN 0021-9991, E-ISSN 1090-2716, Vol. 308, p. 1-19Article in journal (Refereed)
    Abstract [en]

    We propose and implement a new method, called the Ice Sheet Coupled Approximation Levels (ISCAL) method, for simulation of ice sheet flow in large domains during long time-intervals. The method couples the full Stokes (FS) equations with the Shallow Ice Approximation (SIA). The part of the domain where SIA is applied is determined automatically and dynamically based on estimates of the modeling error. For a three dimensional model problem, ISCAL computes the solution substantially faster with a low reduction in accuracy compared to a monolithic FS. Furthermore, ISCAL is shown to be able to detect rapid dynamic changes in the flow. Three different error estimations are applied and compared. Finally, ISCAL is applied to the Greenland Ice Sheet on a quasi-uniform grid, proving ISCAL to be a potential valuable tool for the ice sheet modeling community.

  • 266.
    Ahlmén, Caroline
    University of Gävle. University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Hemligheten bakom populära animerade karaktärer2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Vad gör en framgångsrik animerad karaktär? Homer Simpson, Svampbob Fyrkant och Eric Cartman kommer att analyseras och jämföras för att hitta vad som gör just dem så populära. Därefter kommer de psykologiska aspekterna att granskas. Varför tilltalar dessa karaktärer människor? Riktlinjer för hur man skapar en populär animerad karaktär kommer att utvecklas utifrån resultatet av utredningen.

  • 267.
    Ahlqvist, Oscar
    et al.
    KTH, School of Computer Science and Communication (CSC).
    Åkermark, Wilhelm
    KTH, School of Computer Science and Communication (CSC).
    Examining the Implications of Adding Sentiment Analysis when Clustering based on Party Affiliation through Twitter2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Political discussion is very common and a popular statistic for the politically interested are the surveys determining people’s party affiliation. Today they are done manually but it would be beneficial if there was an automated method which could produce the same or similar results. On the social network Twitter there are a lot of users discussing politics, all from political leaders and representatives to just regular people with an interest for the subject. Because of that and also for its convenience when it comes to collecting data, Twitter has been used before in previous work to cluster political users based on what they are discussing. What has not been done before which this thesis contributes is clustering with sentiment analysis. In other terms, trying to cluster people based on what they are discussing but also if their opinion is positive or negative. What was noted in this work was that the part of clustering without sentiment analysis, that had been done in previous studies, was successfully replicated. However adding the sentiment analysis did not give the desired effect and only worsened the results.

  • 268.
    Ahlstedt, Kristoffer
    et al.
    Linköping University, Department of Computer and Information Science.
    Annerwall, Lovisa
    Linköping University, Department of Computer and Information Science.
    Axelsson, Daniel
    Linköping University, Department of Computer and Information Science.
    Björklund, Samuel
    Linköping University, Department of Computer and Information Science.
    Cedenheim, Oliver
    Linköping University, Department of Computer and Information Science.
    Eriksson, Josefin
    Linköping University, Department of Computer and Information Science.
    Lehtonen, Jesper
    Linköping University, Department of Computer and Information Science.
    Lorentzon, Linn
    Linköping University, Department of Computer and Information Science.
    Olofsson, Gustaf
    Linköping University, Department of Computer and Information Science.
    BryggaHem – Development of an E-commerce Web Application with a Usability Focus2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is part of a bachelor’s project conducted at Linköping University and addresses the development of an e-commerce web application with a usability focus. A market survey was conducted as part of the project to establish the orientation of the web application. Furthermore, the Scrum methodology is described and analyzed, and the team’s experiences of the project are documented. Research relevant to designing an application with high usability is detailed. Additionally the thesis addresses the tools and frameworks used during the development of the application, as well as ethical aspects of handling user information and selling products related to home-brewing of alcoholic beverages. The conclusion drawn from the project regarding the methodology is that Scrum is a viable methodology for this type of development work, although it requires small teams as well as previous experience of Scrum to yield high efficiency. The conclusion drawn from the project regarding usability is that it is achieved through a combination of variables that to a large extent is based on users’ distinct perceptions of the given application. 

  • 269.
    Ahlström, Catharina
    et al.
    Blekinge Institute of Technology, Department of Human Work Science and Media Technology.
    Fridensköld, Kristina
    Blekinge Institute of Technology, Department of Human Work Science and Media Technology.
    How to support and enhance communication: in a student software development project2002Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    This report, in which we have put an emphasis on the word communication, is based on a student software development project conducted during spring 2002. We describe how the use of design tools plays a key role in supporting communication in group activities and to what extent communication can be supported and enhanced by tools such as mock-ups and metaphors in a group project. We also describe a design progress from initial sketches to a final mock-up of a GUI for a postcard demo application.

  • 270.
    Ahlström, Eric
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    Holmqvist, Lucas
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    Goswami, Prashant
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    Comparing Traditional Key Frame and Hybrid Animation2017In: SCA '17 Proceedings of the ACM SIGGRAPH / Eurographics Symposium on Computer Animation, ACM Digital Library, 2017, article id nr. a20Conference paper (Refereed)
    Abstract [en]

    In this research the authors explore a hybrid approach which usesthe basic concept of key frame animation together with proceduralanimation to reduce the number of key frames needed for an animationclip. The two approaches are compared by conducting anexperiment where the participating subjects were asked to ratethem based on their visual appeal.

  • 271.
    Ahlström, Martin
    Linköping University, Department of Computer and Information Science.
    User-centred redesign of a business systemusing the Star Life Cycle method2008Independent thesis Advanced level (degree of Master), 20 points / 30 hpStudent thesis
    Abstract [en]

    The purpose with this thesis was to study user activities in a business system, MediusFlow. The overall objective was to identify user related problems and to analyse which of the usability data gathering methods to use in the future development process of the company Medius.

    The outcome of this study indicated that a cognitive related user problem was the most important problem to solve. A Star Life Cycle method was preferred. Two low-fidelity prototypes were developed to exemplify an alternative design solution to the identified cognitive user problem. Furthermore, the two best methods to use when gathering user related requirements were heuristic evaluation and expert review.

    In addition a company specific Style Guide was created with generic guidelines as a foundation for development of future applications within Medius.

  • 272.
    Ahlström, Petter
    Linköping University, Department of Computer and Information Science, EISLAB - Economic Information Systems. Linköping University, The Institute of Technology.
    Affärsstrategier för seniorbostadsmarknaden2005Licentiate thesis, monograph (Other academic)
    Abstract [sv]

    Den demografiska utvecklingen i Sverige går mot en befolkningssammansättning med allt högre medelålder. Enligt svenska befolkningsprognoser kommer nästan var fjärde svensk år 2025 att vara över 65 år. Den äldre andelen av befolkningen utgör en välbeställd grupp med relativt stora realekonomiska tillgångar. Attitydundersökningar på morgondagens pensionärer talar för att denna grupp ställer högre krav på boendeutformning, kringservice, vård och omsorg än tidigare generationer. Flera studier visar på en ökad betalningsvilja och betalningsförmåga för alternativa service- och boendeformer. Samtidigt försöker olika marknadsaktörer att positionera ett produkt- och tjänsteutbud inom en bostadsmarknadens nischer, här definierad som seniorbostadsmarknaden. På seniorbostadsmarknaden har ett särskilt segment identifierats där utöver seniorboende även service-, vård- och omsorgsrelaterade kringtjänster bjuds ut. Mot den bakgrunden har avhandlingens problemställning formulerats enligt följande: vad skapar en stark marknadsposition för en aktör på seniorbostadsmarknaden med integrerad service, vård och omsorg?

    Utgångspunkten har varit ett sannolikt scenario där privata initiativ i allt större utsträckning kommer att bidra till framtida boendelösningar riktade till samhällets seniora och äldrebefolkningsgrupper. Syftet med avhandlingen har varit dels att identifiera de framgångsfaktorer som kan antas ligger till grund för en stark marknadsposition, dels att skapa en typologi över olika affärsstrategier. Genom en branschanalys har det i avhandlingen påvisats att seniorbostadsmarknaden är en nischmarknad med marginell omfattning. Avhandlingens empiriska undersökning har designats som en fältstudie. Fältstudien har i sin tur bl.a. genomförts i form av en förstudie och en intervjustudie. Intervjustudien ägde rum under hösten 2004 med platsbesök och intervjuer av verksamhetsföreträdare för elva utvalda fallstudieorganisationer. Utifrån ett antal i förhand uppställda kriterier har marknadsaktörernas framgångsfaktorer identifierats. Den bearbetnings- och analysmodell som konstruerats för detta syfte och som använts för att analysera fältstudiens empiri är baserad på studier inom strategiområdet. Modellen har bl.a. inspirerats av forskare som Miles & Snow (1978), Porter (1980) och Gupta & Govindarajan (1984). Vidare bygger den på antagandena om resursers och kompetensers betydelse för strategiformuleringen. Service management, och då särskilt tjänsters sammansättning, är ett annat område som beaktas. Analysmodellen har byggts upp kring fem dimensioner: omgivning, strategi, resurser, tjänstekoncept och konkurrens. De identifierade framgångsfaktorerna har baserats på intervjustudiens två mest framgångsrika aktörer. Resultatet har formulerats i ett antal strategiska vägval vilka kan sammanfattas i begreppen: differentiering, fokus, integration, samverkan, kontroll, verksamhetsutveckling, kärnkompetens och resurser. I avhandlingen påvisas att aktörer som bedriver framgångsrik verksamhet på seniorbostadsmarknaden till stora delar följer det Porter (1980) definierat som en differentieringsstrategi med fokus. Avhandlingen har också utmynnat i en affärsstrategisk typologi för seniorbostadsmarknaden. Dessa tentativa slutsatser har formulerats i fyra strategiska idealtyper: förvaltare, konceptbyggare, entreprenörer och idealister.

  • 273.
    Ahlström, Petter
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Computer and Information Science, EISLAB - Economic Information Systems.
    Nilsson, Fredrik
    Linköping University, The Institute of Technology. Linköping University, Department of Computer and Information Science, EISLAB - Economic Information Systems.
    Affärsstrategier och seniorbostadsmarknaden2005In: Fastighetsnytt, ISSN 1104-8913, Vol. 12 nr 5, p. 36-37Article in journal (Other (popular science, discussion, etc.))
    Abstract [sv]

      Artikeln beskriver några av resultaten från licentiatavhandlingen "Affärsstrategier för seniorbostadsmarknaden" av Petter Ahlström.      

  • 274.
    Ahltorp, Magnus
    KTH, School of Computer Science and Communication (CSC).
    A Personalizable Reading Aid for Second Language Learners of Japanese.2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Magnus Ahltorp

    A Personalizable Reading Aid for Second Language Learners of Japanese

    Second language learners of Japanese today have access to vast amounts of authentic Japanese text, audio and video material. A challenge that the Japanese learner faces though, is that the process of looking up words in a dictionary is prohibitively slow. In this thesis, I describe a personalizable system that helps the user read Japanese text by providing pronunciation information and English explanations at the user's request. I also describe the user-centered development of the system and the results of each iteration of user testing. The resulting system and user testing show that it is feasible to provide an immersive reading experience that both beginners and more advanced language learners can use to take command of a crucial part of their own learning.

  • 275.
    Ahlén, Niclas
    University of Skövde, School of Humanities and Informatics.
    ARAVQ som datareducerare för en klassificeringsuppgift inom datautvinning2004Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [sv]

    Adaptive Resource Allocating Vector Quantizer (ARAVQ) är en teknik för datareducering för mobila robotar. Tekniken har visats framgångsrik i enkla miljöer och det har spekulerats i att den kan fungera som ett generellt datautvinningsverktyg för tidsserier. I rapporten presenteras experiment där ARAVQ används som datareducerare på en artificiell respektive en fysiologisk datamängd inom en datautvinningskontext. Dessa datamängder skiljer sig från tidigare robotikmiljöer i och med att de beskriver objekt med diffusa eller överlappande gränser i indatarymden. Varje datamängd klassificeras efter datareduceringen med hjälp av artificiella neuronnät. Resultatet från experimenten tyder på att klassificering med ARAVQ som datareducerare uppnår ett betydligt lägre resultat än om ARAVQ inte används som datareducerare. Detta antas delvis bero på den låga generaliserbarheten hos de lösningar som skapas av ARAVQ. I diskussionen föreslås att ARAVQ skall kompletteras med en funktion för grannskap, motsvarande den som finns i Self-Organizing Map. Med ett grannskap behålls relationerna mellan de kluster som ARAVQ skapar, vilket antas minska följderna av att en beskrivning hamnar i ett grannkluster

  • 276.
    Ahmad, Azeem
    et al.
    Blekinge Institute of Technology, School of Computing.
    Kolla, Sushma Joseph
    Blekinge Institute of Technology, School of Computing.
    Effective Distribution of Roles and Responsibilities in Global Software Development Teams2012Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Context. Industry is moving from co-located form of development to a distributed development in order to achieve different benefits such as cost reduction, access to skillful labor and around the clock working etc. This transfer requires industry to face different challenges such as communication, coordination and monitoring problems. Risk of project failure can be increased, if industry does not address these problems. This thesis is about providing the solutions of these problems in term of effective roles and responsibilities that may have positive impact on GSD team. Objectives. In this study we have developed framework for suggesting roles and responsibilities for GSD team. This framework consists of problems and casual dependencies between them which are related to team’s ineffectiveness, then suggestions in terms of roles and responsibilities have been presented in order to have an effective team in GSD. This framework, further, has been validated in industry through a survey that determines which are the effective roles and responsibilities in GSD. Methods. We have two research methods in this study 1) systematic literature review and 2) survey. Complete protocol for planning, conducting and reporting the review as well as survey has been described in their respective sections in this thesis. A systematic review is used to develop the framework whereas survey is used for framework validation. We have done static validation of framework. Results. Through SLR, we have identified 30 problems, 33 chains of problems. We have identified 4 different roles and 40 different responsibilities to address these chains of problems. During the validation of the framework, we have validated the links between suggested roles and responsibilities and chains of problems. Addition to this, through survey, we have identified 20 suggestions that represents strong positive impact on chains of problems in GSD in relation to team’s effectiveness. Conclusions. We conclude that implementation of effective roles and responsibilities in GSD team to avoid different problems require considerable attention from researchers and practitioners which can guarantee team’s effectiveness. Implementation of proper roles and responsibilities has been mentioned as one of the successful strategies for increasing team’s effectiveness in the literature, but which particular roles and responsibilities should be implemented still need to be addressed. We also conclude that there must be basic responsibilities associated with any particular role. Moreover, we conclude that there is a need for further development and empirical validation of different frameworks for suggesting roles and responsibilities in full scale industry trials.

  • 277.
    Ahmad, Farooq
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Lindgren, Helena
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Selection of foundational ontology for collaborative knowledge modeling in healthcare domain2010In: Artificial intelligence: methodology, systems, and applications / [ed] Dicheva, Darina; Dochev, Danail, Springer Berlin/Heidelberg, 2010, p. 261-262Conference paper (Refereed)
    Abstract [en]

    Ontology design is an important process for structuring knowledge to be reused in different projects in the health domain. In this paper, we describe an ontology design for the collaborative knowledge building system ACKTUS to be used for developing personalized knowledge applications for different domains. Different foundational ontologies were compared with respect to selected criteria considered vital for the project, such as modularity and descriptiveness.

  • 278.
    Ahmad, Khurram
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering.
    Azeem, Muhammad
    Växjö University, Faculty of Mathematics/Science/Technology, School of Mathematics and Systems Engineering.
    Gold Standard Website2009Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

     

    The aim of this thesis is to design a web base system which provides functionality of comparison between two java files on the basis of point-to information (P2I). User will upload Java files and analysis of Java files called point-to analysis (P2A). System will store the files in the file system for reference and download in later time. System will extract the information called P2I from P2A and it will store that information in the database.

    Database should be flexible to accommodate the changes in P2A file and system should be able to extract the P2I and store it in database with minimum support of system administrator.

     

  • 279.
    AHMAD, MUHAMMAD ZEESHAN
    Blekinge Institute of Technology, School of Engineering.
    Comparative Analysis of Iptables and Shorewall2012Student thesis
    Abstract [en]

    The use of internet has increased over the past years. Many users may not have good intentions. Some people use the internet to gain access to the unauthorized information. Although absolute security of information is not possible for any network connected to the Internet however, firewalls make an important contribution to the network security. A firewall is a barrier placed between the network and the outside world to prevent the unwanted and potentially damaging intrusion of the network. This thesis compares the performance of Linux packet filtering firewalls, i.e. iptables and shorewall. The firewall performance testing helps in selecting the right firewall as needed. In addition, it highlights the strength and weakness of each firewall. Both firewalls were tested by using the identical parameters. During the experiments, recommended benchmarking methodology for firewall performance testing is taken into account as described in RFC 3511. The comparison process includes experiments which are performed by using different tools. To validate the effectiveness of firewalls, several performance metrics such as throughput, latency, connection establishment and teardown rate, HTTP transfer rate and system resource consumption are used. The experimental results indicate that the performance of Iptables firewall decreases as compared to shorewall in all the aspects taken into account. All the selected metrics show that large numbers of filtering rules have a negative impact on the performance of both firewalls. However, UDP throughput is not affected by the number of filtering rules. The experimental results also indicate that traffic sent with different packet sizes do not affect the performance of firewalls.

  • 280.
    Ahmad, Nadeem
    et al.
    Blekinge Institute of Technology, School of Computing.
    Habib, M. Kashif
    Blekinge Institute of Technology, School of Computing.
    Analysis of Network Security Threats and Vulnerabilities by Development & Implementation of a Security Network Monitoring Solution2010Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Communication of confidential data over the internet is becoming more frequent every day. Individuals and organizations are sending their confidential data electronically. It is also common that hackers target these networks. In current times, protecting the data, software and hardware from viruses is, now more than ever, a need and not just a concern. What you need to know about networks these days? How security is implemented to ensure a network? How is security managed? In this paper we will try to address the above questions and give an idea of where we are now standing with the security of the network.

  • 281.
    Ahmad, Raheel
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    On the Scalability of Four Multi-Agent Architectures for Load Control Management in Intelligent Networks2003Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Paralleling the rapid advancement in the network evolution is the need for advanced network traffic management surveillance. The increasing number and variety of services being offered by communication networks has fuelled the demand for optimized load management strategies. The problem of Load Control Management in Intelligent Networks has been studied previously and four Multi-Agent architectures have been proposed. The objective of this thesis is to investigate one of the quality attributes namely, scalability of the four Multi-Agent architectures. The focus of this research would be to resize the network and study the performance of the different architectures in terms of Load Control Management through different scalability attributes. The analysis has been based on experimentation through simulations. It has been revealed through the results that different architectures exhibit different performance behaviors for various scalability attributes at different network sizes. It has been observed that there exists a trade-off in different scalability attributes as the network grows. The factors affecting the network performance at different network settings have been observed. Based on the results from this study it would be easier to design similar networks for optimal performance by controlling the influencing factors and considering the trade-offs involved.

  • 282.
    Ahmad, Rezgar
    KTH, School of Computer Science and Communication (CSC).
    Con curdino – Utökning av tvärflöjtens tonförråd till kvartstoner genom perturbation av tonhålens geometri.2011Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The thesis describes the development and evaluation of a component ('kurdin') that provides flutists the opportunity to play quarter tones on the regular orchestra flute (Böhm flute). The flutist does not need a new instrument or learn a new playing technique.

    Quarter tones were obtained by reducing the diameter of some of the tone holes. The hole diameter is reduced by using the kurdin which is entered inside the flute. The kurdin consists of two parts which can reduce the diameter of two tone holes at the same time. Flutists can thereby extend the available set of scale notes with two quarter tones without changing the position of the kurdin.

    Systematic measurements of the fundamental frequency of four tones (E4, F^#4, A4 and B4) using an artificially blown flute and different versions of the kurdin showed that the pitch of these tones can be lowered a quarter tone (50 cents) with the same reduced hole diameter. The four quarter tones cover almost all scales called Maqamat in oriental music.

  • 283.
    Ahmad, Rezgar
    KTH, School of Computer Science and Communication (CSC), Speech, Music and Hearing, TMH.
    Con curdino – Utökning av tvärflöjtens tonförråd till kvartstoner genom perturbation av tonhålens geometri.2011Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The thesis describes the development and evaluation of a component ('kurdin') that provides flutists the opportunity to play quarter tones on the regular orchestra flute (Böhm flute). The flutist does not need a new instrument or learn a new playing technique.

    Quarter tones were obtained by reducing the diameter of some of the tone holes. The hole diameter is reduced by using the kurdin which is entered inside the flute. The kurdin consists of two parts which can reduce the diameter of two tone holes at the same time. Flutists can thereby extend the available set of scale notes with two quarter tones without changing the position of the kurdin.

    Systematic measurements of the fundamental frequency of four tones (E4, F^#4, A4 and B4) using an artificially blown flute and different versions of the kurdin showed that the pitch of these tones can be lowered a quarter tone (50 cents) with the same reduced hole diameter. The four quarter tones cover almost all scales called Maqamat in oriental music.

  • 284.
    Ahmad, Waqar
    et al.
    Blekinge Institute of Technology, School of Computing.
    Riaz, Asim
    Blekinge Institute of Technology, School of Computing.
    Predicting Friendship Levels in Online Social Networks2010Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Abstract Context: Online social networks such as Facebook, Twitter, and MySpace have become the preferred interaction, entertainment and socializing facility on the Internet. However, these social network services also bring privacy issues in more limelight than ever. Several privacy leakage problems are highlighted in the literature with a variety of suggested countermeasures. Most of these measures further add complexity and management overhead for the user. One ignored aspect with the architecture of online social networks is that they do not offer any mechanism to calculate the strength of relationship between individuals. This information is quite useful to identify possible privacy threats. Objectives: In this study, we identify users’ privacy concerns and their satisfaction regarding privacy control measures provided by online social networks. Furthermore, this study explores data mining techniques to predict the levels/intensity of friendship in online social networks. This study also proposes a technique to utilize predicted friendship levels for privacy preservation in a semi-automatic privacy framework. Methods: An online survey is conducted to analyze Facebook users’ concerns as well as their interaction behavior with their good friends. On the basis of survey results, an experiment is performed to justify practical demonstration of data mining phases. Results: We found that users are concerned to save their private data. As a precautionary measure, they restrain to show their private information on Facebook due to privacy leakage fears. Additionally, individuals also perform some actions which they also feel as privacy vulnerability. This study further identifies that the importance of interaction type varies while communication. This research also discovered, “mutual friends” and “profile visits”, the two non-interaction based estimation metrics. Finally, this study also found an excellent performance of J48 and Naïve Bayes algorithms to classify friendship levels. Conclusions: The users are not satisfied with the privacy measures provided by the online social networks. We establish that the online social networks should offer a privacy mechanism which does not require a lot of privacy control effort from the users. This study also concludes that factors such as current status, interaction type need to be considered with the interaction count method in order to improve its performance. Furthermore, data mining classification algorithms are tailor-made for the prediction of friendship levels.

  • 285.
    Ahmed, Adnan
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Interaction and System Design.
    Hussain, Syed Shahram
    Blekinge Institute of Technology, School of Engineering, Department of Interaction and System Design.
    Meta-Model of Resilient information System2007Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    The role of information systems has become very important in today’s world. It is not only the business organizations who use information systems but the governments also posses’ very critical information systems. The need is to make information systems available at all times under any situation. Information systems must have the capabilities to resist against the dangers to its services,performance & existence, and recover to its normal working state with the available resources in catastrophic situations. The information systems with such a capability can be called resilient information systems. This thesis is written to define resilient information systems, suggest its meta-model and to explain how existing technologies can be utilized for the development of resilient information system.

  • 286.
    Ahmed, Ali
    Linköping University, Department of Computer and Information Science, Human-Centered systems. Linköping University, The Institute of Technology.
    A Systematic Literature Review of "Usability Inspection Methods"2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Objective: Usability inspection methods are a class of usability evaluation methods, applied by usability evaluators to assess usability related aspects of different user interfaces. Different usability inspection methods are proposed so far to evaluate user interfaces in a better way. This systematic literature review summarized different usability evaluation methods, with more focus on two widely used inspection methods. The review also summarized the problems with these two methods and probable proposed solution to cope with these problems.

    Method: A systematic review method as described by Kitchenham [3] was followed to carry out this review. The identified problems in the review were structured in a form of questions. The search to find the relevant data that address the identified questions were conducted on the basis of planned search strategies. Papers were selected on the basis of inclusion and exclusion criteria in accordance with the quality checklist; followed by data extraction and synthesis strictly characterized by quality checklist, inclusion and exclusion criteria to attain better results.

    Results and discussion: Despite of its advantages there still exists many weaknesses in Heuristic evaluation (HE) and Cognitive walk-through (CW) methods. Different studies have highlighted different factors that may influence the results. Those factors include number of evaluators, evaluator’s perception and experience, time, environment, cost, indigenous design, the way method applied and acquired software.

    Conclusion: To get better evaluation results, it is best to use different techniques for usability evaluation of single software or optimize existing techniques.

  • 287.
    Ahmed, Iftikhar
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Farooq, Muhammad
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Switched Multi-hop Priority Queued Networks-Influence of priority levels on Soft Real-time Performance2010Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    In the last few years, the number of real-time applications has increased. These applications are sensitive and require the methods to utilize existing network capacity efficiently to meet performance requirements and achieve the maximum throughput to overcome delay, jitter and packet loss. In such cases, when the network needs to support highly interactive traffic like packet-switched voice, the network congestion is an issue that can lead to various problems. If the level of congestion is high enough, the users may not be able to complete their calls and have existing calls dropped or may experience a variety of delays that make it difficult to participate smooth conversation.

    In this paper, we investigate the effect of priority levels on soft real-time performance. We use the priority queues to help us manage the congestion, handle the interactive traffic and improve the over all performance of the system. We consider switched multi-hop network with priority queues. All the switches and end-nodes control the real-time traffic with “Earlier Deadline First” scheduling. The performance of the network is characterized in terms of the average delay, the deadline missing ratio and the throughput.

    We will analyze these parameters with both the bursty traffic and evenly distributed traffic. We will analyze different priority levels and will see how the increase in priority level increases the performance of the soft real-time system.

  • 288.
    Ahmed, Kachkach
    KTH, School of Computer Science and Communication (CSC).
    Analyzing user behavior and sentiment in music streaming services2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    These last years, streaming services (for music, podcasts, TV shows and movies) have been under the spotlight by disrupting traditional media consumption platforms. If the technical implications of streaming huge amounts of data are well researched, much remains to be done to analyze the wealth of data collected by these services and exploit it to its full potential in order to improve them. Using raw data about users’ interactions with the music streaming service Spotify, this thesis focuses on three main concepts: streaming context, user attention and the sequential analysis of user actions. We discuss the importance of each of these aspects and propose different statistical and machine learning techniques to model them. We show how these models can be used to improve streaming services by inferring user sentiment and improving recommender systems, characterizing user sessions, extracting behavioral patterns and providing useful business metrics.

  • 289.
    Ahmed, Laeeq
    et al.
    KTH, School of Computer Science and Communication (CSC), High Performance Computing and Visualization (HPCViz).
    Edlund, Åke
    KTH, School of Computer Science and Communication (CSC), High Performance Computing and Visualization (HPCViz).
    Laure, Erwin
    KTH, School of Computer Science and Communication (CSC), High Performance Computing and Visualization (HPCViz).
    Spjuth, O.
    Using iterative MapReduce for parallel virtual screening2013In: 2013 IEEE 5th International Conference on Cloud Computing Technology and Science (CloudCom), IEEE Computer Society, 2013, p. 27-32Conference paper (Refereed)
    Abstract [en]

    Virtual Screening is a technique in chemo informatics used for Drug discovery by searching large libraries of molecule structures. Virtual Screening often uses SVM, a supervised machine learning technique used for regression and classification analysis. Virtual screening using SVM not only involves huge datasets, but it is also compute expensive with a complexity that can grow at least up to O(n2). SVM based applications most commonly use MPI, which becomes complex and impractical with large datasets. As an alternative to MPI, MapReduce, and its different implementations, have been successfully used on commodity clusters for analysis of data for problems with very large datasets. Due to the large libraries of molecule structures in virtual screening, it becomes a good candidate for MapReduce. In this paper we present a MapReduce implementation of SVM based virtual screening, using Spark, an iterative MapReduce programming model. We show that our implementation has a good scaling behaviour and opens up the possibility of using huge public cloud infrastructures efficiently for virtual screening.

  • 290.
    Ahmed, Laeeq
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Computational Science and Technology (CST).
    Georgiev, Valentin
    Capuccini, Marco
    Toor, Salman
    Schaal, Wesley
    Laure, Erwin
    KTH, School of Electrical Engineering and Computer Science (EECS), Computational Science and Technology (CST).
    Spjuth, Ola
    Efficient iterative virtual screening with Apache Spark and conformal prediction2018In: Journal of Cheminformatics, ISSN 1758-2946, E-ISSN 1758-2946, Vol. 10, article id 8Article in journal (Refereed)
    Abstract [en]

    Background: Docking and scoring large libraries of ligands against target proteins forms the basis of structure-based virtual screening. The problem is trivially parallelizable, and calculations are generally carried out on computer clusters or on large workstations in a brute force manner, by docking and scoring all available ligands. Contribution: In this study we propose a strategy that is based on iteratively docking a set of ligands to form a training set, training a ligand-based model on this set, and predicting the remainder of the ligands to exclude those predicted as 'low-scoring' ligands. Then, another set of ligands are docked, the model is retrained and the process is repeated until a certain model efficiency level is reached. Thereafter, the remaining ligands are docked or excluded based on this model. We use SVM and conformal prediction to deliver valid prediction intervals for ranking the predicted ligands, and Apache Spark to parallelize both the docking and the modeling. Results: We show on 4 different targets that conformal prediction based virtual screening (CPVS) is able to reduce the number of docked molecules by 62.61% while retaining an accuracy for the top 30 hits of 94% on average and a speedup of 3.7. The implementation is available as open source via GitHub (https://github.com/laeeq80/spark-cpvs) and can be run on high-performance computers as well as on cloud resources.

  • 291.
    Ahmed, Mamun
    Blekinge Institute of Technology, School of Engineering.
    Adaptive Sub band GSC Beam forming using Linear Microphone-Array for Noise Reduction/Speech Enhancement.2012Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    This project presents the description, design and the implementation of a 4-channel microphone array that is an adaptive sub-band generalized side lobe canceller (GSC) beam former uses for video conferencing, hands-free telephony etc, in a noisy environment for speech enhancement as well as noise suppression. The side lobe canceller evaluated with both Least Mean Square (LMS) and Normalized Least Mean Square (NLMS) adaptation. A testing structure is presented; which involves a linear 4-microphone array connected to collect the data. Tests were done using one target signal source and one noise source. In each microphone’s, data were collected via fractional time delay filtering then it is divided into sub-bands and applied GSC to each of the subsequent sub-bands. The overall Signal to Noise Ratio (SNR) improvement is determined from the main signal and noise input and output powers, with signal-only and noise-only as the input to the GSC. The NLMS algorithm significantly improves the speech quality with noise suppression levels up to 13 dB while LMS algorithm is giving up to 10 dB. All of the processing for this thesis is implemented on a computer using MATLAB and validated by considering different SNR measure under various types of blocking matrix, different step sizes, different noise locations and variable SNR with noise.

  • 292.
    Ahmed, Mobyen Uddin
    Mälardalen University, School of Innovation, Design and Engineering.
    A case-based multi-modal clinical system for stress management2010Licentiate thesis, monograph (Other academic)
    Abstract [en]

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

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

  • 293.
    Ahmed, Mobyen Uddin
    et al.
    Örebro University, School of Science and Technology.
    Banaee, Hadi
    Örebro University, School of Science and Technology.
    Rafael-Palou, Xavier
    Barcelona Digital Technology Centre, Barcelona, Spain.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Intelligent Healthcare Services to Support Health Monitoring of Elderly2015In: INTERNET OF THINGS: USER-CENTRIC IOT, PT I, Springer, 2015, Vol. 150, p. 178-186Conference paper (Refereed)
    Abstract [en]

    This paper proposed an approach of intelligent healthcare services to support health monitoring of old people through the project named SAAPHO. Here, definition and architecture of the proposed healthcare services are presented considering six different health parameters such as: 1) physical activity, 2) blood pressure, 3) glucose, 4) medication compliance, 5) pulse monitoring and 6) weight monitoring. The outcome of the proposed services is evaluated in a case study where total 201 subjects from Spain and Slovenia are involved for user requirements analysis considering 1) end users, 2) clinicians, and 3) field study analysis perspectives. The result shows the potentiality and competence of the proposed healthcare services for the users.

  • 294.
    Ahmed, Mobyen Uddin
    et al.
    Mälardalen University, Sweden.
    Fotouhi, Hossein
    Mälardalen University, Sweden.
    Köckemann, Uwe
    Örebro University, Sweden.
    Lindén, Maria
    Mälardalen University, Sweden.
    Tomasic, Ivan
    Mälardalen University, Sweden.
    Tsiftes, Nicolas
    RISE - Research Institutes of Sweden, ICT, SICS.
    Voigt, Thiemo
    RISE - Research Institutes of Sweden, ICT, SICS.
    Run-Time Assurance for the E-care@home System2017Conference paper (Refereed)
  • 295.
    Ahmed, Mobyen Uddin
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Physical Activity Classification for Elderly based on Pulse Rate2013Conference paper (Refereed)
    Abstract [en]

    Physical activity is one of the key components for elderly in order to be actively ageing. However, it is difficult to differentiate and identify the body movement and actual physical activity using only accelerometer measurement. Therefore, this paper presents an application of case-based retrieval classification scheme to classify the physical activity of elderly based on pulse rate measurements. Here, case-based retrieval approach used the features extracted from both time and frequency domain. The evaluation result shows the best accuracy performance while considering the combination of time and frequency domain features. According to the evaluation result while considering the control measurements, the sensitivity, specificity and overall accuracy are achieved as 95%, 96% and 96% respectively. Considering the test dataset, the system was succeeded to identify 13 physical activities out of 16 i.e. the percentage of the correctness was 81%.

  • 296.
    Ahmed, Mobyen Uddin
    et al.
    Örebro University, School of Science and Technology.
    Loutfi, Amy
    Örebro University, School of Science and Technology.
    Physical activity identification using supervised machine learning and based on pulse rate2013In: International Journal of Advanced Computer Sciences and Applications, ISSN 2158-107X, E-ISSN 2156-5570, Vol. 4, no 7, p. 210-217Article in journal (Refereed)
    Abstract [en]

    Physical activity is one of the key components for elderly in order to be actively ageing. Pulse rate is a convenient physiological parameter to identify elderly’s physical activity since it increases with activity and decreases with rest. However, analysis and classification of pulse rate is often difficult due to personal variation during activity. This paper proposed a Case-Based Reasoning (CBR) approach to identify physical activity of elderly based on pulse rate. The proposed CBR approach has been compared with the two popular classification techniques, i.e. Support Vector Machine (SVM) and Neural Network (NN). The comparison has been conducted through an empirical experimental study where three experiments with 192 pulse rate measurement data are used. The experiment result shows that the proposed CBR approach outperforms the other two methods. Finally, the CBR approach identifies physical activity of elderly 84% accurately based on pulse rate

  • 297.
    Ahmed, Nisar
    et al.
    Blekinge Institute of Technology, School of Computing.
    Yousaf, Shahid
    Blekinge Institute of Technology, School of Computing.
    For Improved Energy Economy – How Can Extended Smart Metering Be Displayed?2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Context: A District Heating System (DHS) uses a central heating plant to produce and distribute hot water in a community. Such a plant is connected with consumers’ premises to provide them with hot water and space heating facilities. Variations in the consumption of heat energy depend upon different factors like difference in energy prices, living standards, environmental effects and economical conditions etc. These factors can manage intelligently by advanced tools of Information and Communication Technology (ICT) such as smart metering. That is a new and emerging technology; used normally for metering of District Heating (DH), district cooling, electricity and gas. Traditional meters measures overall consumption of energy, in contrast smart meters have the ability to frequently record and transmit energy consumption statistics to both energy providers and consumers by using their communication networks and network management systems. Objectives: First objective of conducted study was providing energy consumption/saving suggestions on smart metering display for accepted consumer behavior, proposed by the energy providers. Our second objective was analysis of financial benefits for the energy provides, which could be expected through better consumer behavior. Third objective was analysis of energy consumption behavior of the residential consumes that how we can support it. Moreover, forth objective of the study was to use extracted suggestions of consumer behaviors to propose Extended Smart Metering Display for improving energy economy. Methods: In this study a background study was conducted to develop basic understanding about District Heat Energy (DHE), smart meters and their existing display, consumer behaviors and its effects on energy consumption. Moreover, interviews were conducted with representatives of smart heat meters’ manufacturer, energy providers and residential consumers. Interviews’ findings enabled us to propose an Extended Smart Metering Display, that satisfies recommendations received from all the interviewees and background study. Further in this study, a workshop was conducted for the evaluation of the proposed Extended Smart Metering Display which involved representatives of smart heat meters’ manufacture and residential energy consumers. DHE providers also contributed in this workshop through their comments in online conversation, for which an evaluation request was sent to member companies of Swedish District Heating Association. Results: Informants in this research have different levels of experiences. Through a systematic procedure we have obtained and analyzed findings from all the informants. To fulfill the energy demands during peak hours, the informants emphasized on providing efficient energy consumption behavior to be displayed on smart heat meters. According to the informants, efficient energy consumption behavior can be presented through energy consumption/saving suggestions on display of smart meters. These suggestions are related to daily life activities like taking bath and shower, cleaning, washing and heating usage. We analyzed that efficient energy consumption behavior recommended by the energy providers can provide financial improvements both for the energy providers and the residential consumers. On the basis of these findings, we proposed Extended Smart Metering Display to present information in simple and interactive way. Furthermore, the proposed Extended Smart Metering Display can also be helpful in measuring consumers’ energy consumption behavior effectively. Conclusions: After obtaining answers of the research questions, we concluded that extension of existing smart heat meters’ display can effectively help the energy providers and the residential consumers to utilize the resources efficiently. That is, it will not only reduce energy bills for the residential consumers, but it will also help the energy provider to save scarce energy and enable them to serve the consumers better in peak hours. After deployment of the proposed Extended Smart Metering Display the energy providers will able to support the consumers’ behavior in a reliable way and the consumers will find/follow the energy consumption/saving guidelines easily.

  • 298.
    Ahmed, Qutub Uddin
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Mujib, Saifullah Bin
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Context Aware Reminder System: Activity Recognition Using Smartphone Accelerometer and Gyroscope Sensors Supporting Context-Based Reminder Systems2014Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Context. Reminder system offers flexibility in daily life activities and assists to be independent. The reminder system not only helps reminding daily life activities, but also serves to a great extent for the people who deal with health care issues. For example, a health supervisor who monitors people with different health related problems like people with disabilities or mild dementia. Traditional reminders which are based on a set of defined activities are not enough to address the necessity in a wider context. To make the reminder more flexible, the user’s current activities or contexts are needed to be considered. To recognize user’s current activity, different types of sensors can be used. These sensors are available in Smartphone which can assist in building a more contextual reminder system. Objectives. To make a reminder context based, it is important to identify the context and also user’s activities are needed to be recognized in a particular moment. Keeping this notion in mind, this research aims to understand the relevant context and activities, identify an effective way to recognize user’s three different activities (drinking, walking and jogging) using Smartphone sensors (accelerometer and gyroscope) and propose a model to use the properties of the identification of the activity recognition. Methods. This research combined a survey and interview with an exploratory Smartphone sensor experiment to recognize user’s activity. An online survey was conducted with 29 participants and interviews were held in cooperation with the Karlskrona Municipality. Four elderly people participated in the interview. For the experiment, three different user activity data were collected using Smartphone sensors and analyzed to identify the pattern for different activities. Moreover, a model is proposed to exploit the properties of the activity pattern. The performance of the proposed model was evaluated using machine learning tool, WEKA. Results. Survey and interviews helped to understand the important activities of daily living which can be considered to design the reminder system, how and when it should be used. For instance, most of the participants in the survey are used to using some sort of reminder system, most of them use a Smartphone, and one of the most important tasks they forget is to take their medicine. These findings helped in experiment. However, from the experiment, different patterns have been observed for three different activities. For walking and jogging, the pattern is discrete. On the other hand, for drinking activity, the pattern is complex and sometimes can overlap with other activities or can get noisy. Conclusions. Survey, interviews and the background study provided a set of evidences fostering reminder system based on users’ activity is essential in daily life. A large number of Smartphone users promoted this research to select a Smartphone based on sensors to identify users’ activity which aims to develop an activity based reminder system. The study was to identify the data pattern by applying some simple mathematical calculations in recorded Smartphone sensors (accelerometer and gyroscope) data. The approach evaluated with 99% accuracy in the experimental data. However, the study concluded by proposing a model to use the properties of the identification of the activities and developing a prototype of a reminder system. This study performed preliminary tests on the model, but there is a need for further empirical validation and verification of the model.

  • 299.
    Ahmed, Rakiv
    et al.
    KTH, School of Computer Science and Communication (CSC).
    Aule, Jonas
    KTH, School of Computer Science and Communication (CSC).
    An Evaluation of the Framework Libgdx when Developing a Game Prototype for Android Devices.2011Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    An evaluation of the framework Libgdx

    when developing a game prototype for Android devices

    By: Rakiv Ahmed & Jonas Aule

    ABSTRACT

    This paper is about evaluation of the framework Libgdx, regarding 2D game development for the Android platform. Other frameworks are also investigated briefly. The game under development is an original game called Magnificent Marbles and is multi-modal as other games for smartphones. The Background section talks about the Android platform and its related tools along with game examples, also frameworks are introduced here. The main focus of this paper will be on the Implementation section and the actual usage of Libgdx. Methods and results for different development versions of the game will be displayed.

    The Discussion section concludes that Libgdx is a good framework due to its desktop support. Libgdx may not suitable for smaller game projects or when wanting to get started quickly without too much knowledge in other areas, such as OpenGL. Another issue is that one should not solely rely on Libgdx desktop support, but knowledge in other areas is required as well to utilize Libgdx to the fullest. The Appendix section includes different documents for more information about Magnificent Marbles.

  • 300.
    Ahmed, Rehan M.
    et al.
    Örebro University, School of Science and Technology.
    Ananiev, Anani V.
    Örebro University, School of Science and Technology.
    Kalaykov, Ivan
    Örebro University, School of Science and Technology.
    Compliant motion control for safe human robot interaction2009In: Robot motion and control 2009 / [ed] Krzysztof R. Kozłowski, Berlin: Springer , 2009, p. 265-274Conference paper (Refereed)
    Abstract [en]

    Robots have recently been foreseen to work side by side and share workspace with humans in assisting them in tasks that include physical human-robot (HR) interaction. The physical contact with human tasks under uncertainty has to be performed in a stable and safe manner [6]. However, current industrial robot manipulators are still very far from HR coexisting environments, because of their unreliable safety, rigidity and heavy structure. Besides this, the industrial norms separate the two spaces occupied by a human and a robot by means of physical fence or wall [9]. Therefore, the success of such physical HR interaction is possible if the robot is enabled to handle this interaction in a smart way to prevent injuries and damages.

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