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  • 951.
    Axelsson, Gabriella
    Blekinge Institute of Technology, School of Management.
    Ojänmnlikhet i Colombia: En analys utifrån Charles Tillys teori om kategoriell ojämnlikhet2008Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Abstract The people of Colombia suffer from a deep spiral of internal conflicts and unstable social conditions. The aim of this study is to highlight inequality in Colombia by applying Charles Tilly’s theory of durable inequality through categorical pairs. A qualitative method is applied in order to gain deeper insight to inequality in Colombia. The essay examines the phenomenon by completing a content analysis. The breakdown is limited to four study categories: gender, crime, health and social stratification. Categorical inequality is further analysed through Tilly’s four mechanisms: exploitation, adaptation, emulation and opportunity hoarding. A coding scheme is used in order to heighten the reliability and validity. Code entities (study categories) are examined through specific code variables. The method is further improved by reinterpretation of the content and analysis of Tillys’ mechanisms. Results confirm the serious condition of internal conflicts in Colmbia. Social stratifiction have wide-reaching effects. Furthermore, the results show that the internal conflicts create a multiplication effect with adverse consequences for Colombia’s society further destabilising the country’s condition. Minority groups such as internally displaced or indigenous Indian tribes are treated unfairly. Elites including the state benefit from the power which they hold. The less fortunate and minority groups are those who are most vulnerable. Women are subject to violence and excluded for reasons varying from a wide range of areas including the job market. The opportunity for good circumstances and well being in addition to fundamental medical treatment are not available for the general society. Furthermore, difficult living circumstances both social and environmental further complicate the circumstances. Moreover, results show inadequate measures what concerns to the implementation of human rights. Sharp contrasts are observed between categorical pairs such as poor and rich, men and women, criminal and non-criminal, and well-being and illness. A relative pattern between Tilly’s four mechanisms can also be recognized and made possible through local knowledge and the script of the people. One of the main conclusions is that local authorities are called upon to advance measures in order to minimise the current exploitation. In particular it is important that these measures are applied vigorously whilst there is also a great need to work with awareness raising strategies in Colombia. Abstrakt Colombia har en lång historia av väpnade konflikter och instabila sociala relationer. Uppsatsens syfte är att belysa hur ojämnlikhet i Colombia ur Charles Tillys teori om kategoriell ojämnlikhet. En begränsning görs till att undersöka ojämnlikhet utifrån fyra studiekategorier: kön, brottslighet, hälsa och social differentiering. Den kategoriella ojämnlikheten analyseras genom Tillys fyra orsaksmekansimer: exploatering, anpassning, efterlikning och möjllighetsansamling. En kvalitativ metod tillämpas för att fördjupa förståelsen av ojämlikhet. Genom en innehållsanalys undersöks hur den kategoriella ojämlikheten uttrycks i Colombia. Ett kodningsschema appliceras för att höja realibiliteten samt validitet ur vilka kodningenheter (studiekategorier) tolkas utifrån kodningsvariabler. Metoden stärks ytterligare av en tydlig kondingsintruktion som ger utrymme för omtolkning av resultaten och analys av Tillys fyra orsaksmekanismer. Resultaten bekräftar den allvariga interna konflikten i Colombia och åskådligör olika grupper svåra livssituation i samhället. Den social stratifieringen har ubredd konskevens för den colombianska befolkningen. Resultaten pekar vidare på att den interna konflikten bidrar till ett multiplikatseffekt vilket missgynnar befolkningen och bidrar till ytterligare destabilisering av Colombia. Minoritetsgrupper som till exempel internflyktingar och den urhemska indianbefolkningen missgynnas. Elitgrupper, därtill staten, drar nytta av den makt de besitter på orättmättlig bekostnad av befolkningen. Fattiga och mindre sociala grupper drabbas värst. Kvinnor utsätts för grovt våld och stängs ut av samhället på en rad olika arenor bland annat arbetsmarknad och våld. Tillgång till goda omständigheter och välbefinnande samt fundamentala läkarresurser finns inte tillgängliga till den allmänna befolkningen samtidigt som svåra levnadsförhållande både sociala och och miljö omständigheter försvårar situationen. Vidare visar resultatet bristande åtgärder vad gäller appliceringen av mänskliga rättigheter. Skarpa skillnader mellan kategoriella par såsom fattiga och rika, män och kvinnor, brottliga och icke-brottsliga samt välmående och icke-välmående urskiljs. Ett relativt mönster kan observeras genom Tillys fyra orsaksmekanismer. Det blir möjligt genom den lokala kunskapen och skript av den colombianska befolkningen. De framgår tydligt att statliga myndigheter bör inrätta fler åtgärder för att minska den exploatering som finns i samhället och att dessa rättsregler måste implementeras med allvar samtidigt som det finns ett stort utrymme för att arebta med en ökad medventehet is samhället.

  • 952.
    Axelsson, John
    et al.
    Blekinge Institute of Technology, Department of Business Administration and Social Science.
    Runnman, Fredrik
    Blekinge Institute of Technology, Department of Business Administration and Social Science.
    Vilka är bankernas interna drivkrafter för att utveckla finansiella tjänster på Internet?2003Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Syfte: Förstå hur bankens marknadsstrategier, tekniska och organisatoriska utveckling har påverkat utvecklingen av finansiella tjänster på Internet Metod Den metod vi har använt oss av är kvalitativa forskningsintervjuer med beslutsfattare inom det svenska bankväsendet. Genom att göra personliga intervjuer uppkom det en helt annan kontakt med respondenten. Tanken var även att vi skulle intervjua personer på bankerna vilka dagligen arbetar med liknande frågor, detta för att få så bra kvalitet som möjligt på de svar som vi fick. Vi valde att intervjua två av de fyra stora svenska bankerna, valet föll på Handelsbanken och SEB. Slutsats Det finns primära och sekundära strategier bakom utvecklingen av finansiella tjänster på Internet i Sverige. Dessa strategier är integrerade med varandra. De primära strategier vi identifierat är de marknadsmässiga och den organisatoriska utvecklingen, där vi anser att marknadsstrategin haft störst betydelse vid införandet av finansiella tjänster på Internet i Sverige. Den organisatoriska strategin ser vi som sekundär genom att organisationen även kan utgöra ett hinder.

  • 953.
    Axelsson, Jonas
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    Comparison of user accuracy and speed when performing 3D game target practice using a computer monitor and virtual reality headset2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Consumer grade Virtual Reality (VR)-headsets are on the rise, and with them comes an increasing number of digital games which support VR. How players perceive the gameplay and how well they perform at the games tasks can be key factors to designing new games.

    This master’s thesis aims to evaluate if a user can performa game task, specifically a target practice, in less time and/or more accurately when using a VR-headset as opposed to a computer screen and mouse. To gather statistics and measure the differences, an experiment was conducted using a test application developed alongside this report. The experiment recorded accuracy scores and time taken in tests performed by 35 test participants using both a VR-headset and computer screen.

    The resulting data sets are presented in the results chapter of this report. A Kolmogorov-Smirnov Normality Test and Student’s paired samples t-test was performed on the data to establish its statistical significance. After analysis, the results are reviewed, discussed and conclusions are made.

    This study concludes that when performing the experiment, the use of a VR-headset decreased the users accuracy and to a lesser extent also increased the time the user took to hit all targets. An argument was made that the longer previous experience with computer screen and mouse of most users gave this method an unfair advantage. With equally long training, VR use might score similar results.

  • 954.
    Axelsson, Kristina
    Blekinge Institute of Technology, School of Planning and Media Design.
    Skillingaryd en attraktiv ort i Småland2010Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [sv]

    Skillingaryd en ort i Vaggeryds kommun med ca 3800 invånare. Det är ett litet samhälle med allt vad det innebär. Varför väljer man att bo så? Vilken sorts livsmiljö är Skillingaryd? Vad är det som gör orten attraktiv? För att besvara frågorna ovan görs en ortsanalys som undersöker vilken typ av livsmiljö Skillingaryd är och som speglar hur Skillingarydsborna ser på sin ort och på sin vardag på orten. För att få en inblick i Skillingarydsbornas vardag tillfrågas en samling personer som bor på orten eller har en koppling till orten om deras syn på samhället. Till ortsanalysen används även tillgängligt statistiskt material och inventeringar gjorda på platsen. Den insamlade informationen leder fram till en sammanställning av planeringsproblem och planeringsmöjligheter för en liten ort. Den lilla ortens förutsättningar skiljer sig från en stads, men vissa av stadens problem och möjligheter finns även på den lilla orten i en annan skala eller i ett annat sammanhang. Vissa av dessa problem och möjligheter har en koppling till fysisk planering och dessa följs upp i ett planförslag som syftar till att stärka Skillingaryds attraktivitet utifrån en planerares syn på orten. Bland annat föreslås ny markanvändning, ny grönstruktur och ny gatustruktur.

  • 955.
    Axelsson, Linnéa
    et al.
    Blekinge Institute of Technology, School of Health Science.
    Roos, Sophie
    Blekinge Institute of Technology, School of Health Science.
    Faktorer som utifrån sjuksköterskans perspektiv påverkar vårdrelationen: En litteraturstudie om ätstörningar2013Student thesis
    Abstract [sv]

    Bakgrund: Enligt Nationellt kvalitetsregister för ätstörningar (2010) är ätstörningar ett vanligt, allvarligt och ökande hälsoproblem. Således är det med största sannolikhet att en sjuksköterska någon gång i sin yrkesverksamma roll kommer att interagera med denna patientgrupp. Enligt svensk hälso- och sjukvårdslag (1982:763) skall sjuksköterskan främja en god kontakt till patienten och omvårdnaden skall i största möjliga mån utformas och genomföras i samråd med patienten. En vårdrelation är essentiell för att uppnå hälsa och välbefinnande, därmed är det av betydelse att sjuksköterskan har förståelse för faktorer som påverkar interaktionen i vårdrelationen. Syfte: Syftet var att belysa faktorer som utifrån sjuksköterskans perspektiv påverkar interaktionen i vårdrelationen med en patient med en ätstörning. Metod: En litteraturstudie med en kvalitativ ansats baserad på sex vårdvetenskapliga artiklar. Artiklarna kvalitetsgranskandes enligt Willman, Stoltz och Bathsevanis granskningsprotokoll. Analyseringen genomfördes med hjälp av Graneheim och Lundmans tolkning av Krippendorfs innehållsanalys. Resultat: I resultatet framkom att sjuksköterskans bristande kunskap, sjuksköterskans känslomässiga ambivalens samt sjuksköterskans förmåga att visa intresse för patienten var faktorer som utifrån sjuksköterskans perspektiv påverkade interaktionen i vårdrelationen. Slutsats: Resultatet visar att sjuksköterskans brist på kunskap kan orsaka ett onödigt lidande hos patienten samt att sjuksköterskan ofta upplever det problematiskt och känslomässigt påfrestande att vårda en patient med en ätstörning. En bristfällig interaktion kan få ogynnsamma konsekvenser för vidare utveckling av en vårdrelation. Området är således i behov av vidare forskning, så att framtida och yrkesverksamma sjuksköterskor kan öka möjligheten att skapa en vårdrelation med en patient med en ätstörning.

  • 956.
    Axelsson, Lisa
    Blekinge Institute of Technology, Faculty of Health Sciences, Department of Health.
    Informatikens betydelse för omvårdnadsarbetet: En systematisk litteraturövrsikt i svensk hälso- och sjukvårdskontext2015Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [sv]

    Hälso- och sjukvården står inför en stor utmaning, både i Sverige och i världen. Kraven ökar på både kvalitet, säkerhet och effektivitet. Informatik är ett värdefullt verktyg för att hantera dessa nya krav. Trots det nyttjas inte den tillgängliga informations- och kommunikationsteknologin fullt ut. Den här systematiska litteraturstudien undersöker vilken betydelse informatik har för omvårdnadsarbetet, ur sjuksköterskor verksamma i svensk hälso- och sjukvårds perspektiv. Studien är en integrerad litteraturstudie, där både kvalitativ och kvantitativ forskning inkluderas och analyseras utifrån critical realism. Resultatet har sorterats i kategorierna ”Uppfattningar om att arbeta med informatik” och ”Erfarenheter relaterade till implementeringen” och visar att informatik är värdeskapande för sjuksköterskor, i synnerhet inom hemsjukvård. En traditionell hierarkisk maktstruktur inom hälso- och sjukvården bromsar dessvärre utvecklingen mot en hälso- och sjukvård där informatik används optimalt. Studenter på specialistsjuksköterskeutbildningar skulle kunna spela en nyckelroll i utvecklingen och insatser för att öka informatikkompetensen bör riktas mot denna grupp.

  • 957.
    Axelsson, Malin
    et al.
    Blekinge Institute of Technology, School of Management.
    Eliasson, Nettan
    Blekinge Institute of Technology, School of Management.
    Manligt och kvinnligt missbruk: Livshistorier om vägen in, tiden under och vägen ut ur missbruk.2007Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Alcohol and drug abuse is something that undoubtedly exists in our society today. Our interest in this area was inspired by an earlier study of the influence of socialization on these dependencies. From this we developed new hypotheses concerning men and women’s drug and alcohol abuse. The main purpose of this study was to highlight the experiences and reflections of six women and seven men on their own alcohol or drug abuse. We hoped to reach an understand of how these men and women perceived the road to, the time during, and the way out of their addictions. Our research methods were qualitative and material was collected on their life history by conducting semi-structured interviews, mostly through email. Two interviews were carried out in a different manner; one occurred over the telephone and another in person. Of the selected individuals, seven were men and six were women, all of whom have had a history of alcohol and/or drug abuse but now are alcohol and drug free. Our exploration of the topic began with a literature study where earlier research had showed that drug and alcohol abuse among men and women could have different causes and forms, but that there are common factors as well between them. Our collected information was analysed using a narrative analysis, and the result was consistent with Erving Goffman’s theory of stigmatisation and Robert W. Connell’s theories on gender and gender relations. The result was that many differences could be seen between men and women, but that typical gender-related patterns were also seen, for example that the men spoke more about their work and the women more about their children. When looking at a chronological timeline of the individual’s life it was clear how one event often caused another event, and we could see how these affected the person. From this we concluded that an individual’s childhood and adolescence could contribute to a feeling of being an outsider and that through alcohol and drugs they are able to find a community they can be accepted in and a new way to define themselves. To summarize, the study showed that there are more similarities than differences between men and women and that their interpretation of their addictions demonstrates similar thought patterns in regards to feeling like an outsider, social ties, abuse and children, their sense of self, confirmation and insights.

  • 958.
    Axelsson, Mattias
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Systems and Software Engineering.
    Sonesson, Johan
    Blekinge Institute of Technology, School of Engineering, Department of Systems and Software Engineering.
    Business Process Performance Measurement for Rollout Success2004Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Business process improvement for increased product quality is of continuous importance in the software industry. Quality managers in this sector need effective, hands-on tools for decision-making in engineering projects and for rapidly spotting key improvement areas. Measurement programs are a widespread approach for introducing quality improvement in software processes, yet employing all-embracing state-of-the art quality assurance models is labor intensive. Unfortunately, these do not primarily focus on measures, revealing a need for an instant and straightforward technique for identifying and defining measures in projects without resources or need for entire measurement programs. This thesis explores and compares prevailing quality assurance models using measures, rendering the Measurement Discovery Process constructed from selected parts of the PSM and GQM techniques. The composed process is applied to an industrial project with the given prerequisites, providing a set of measures that are subsequently evaluated. In addition, the application gives foundation for analysis of the Measurement Discovery Process. The application and analysis of the process show its general applicability to projects with similar constraints as well as the importance of formal target processes and exhaustive project domain knowledge among measurement implementers. Even though the Measurement Discovery Process is subject to future refinement, it is clearly a step towards rapid delivery of tangible business performance indicators for process improvement.

  • 959.
    Axelsson, Mattis
    et al.
    Blekinge Institute of Technology, School of Planning and Media Design.
    Larsson, Sara
    Blekinge Institute of Technology, School of Planning and Media Design.
    Utvecklande AI: En studie i hur man skapar ett system för lärande AI2013Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    AI is something that has become more important in today’s games and gets higher pressure to act human and intelligent. This thesis examines which methods are preferred when creating an AI that can learn from its previous experiences. Some of the methods that are examined are tree structures, Artificial Neural Network and GoCap. By creating an application with one of the methods and a survey of how the AI in the application was perceived we got a result that showed us if the method was functional. From this we discuss if the other methods would have been more effective, how we could have improved the AI and what the future for game-AI holds.

  • 960.
    Axelsson, Moa
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Gulliksson, Linnea
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Sjuksköterskors erfarenhet av användning av tolk vid språkbarriärer: En kvalitativ litteraturstudie2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Samhället blir allt mer mångkulturellt och en större press sätts på att sjuksköterskor kan möjliggöra en fungerande kommunikation med patienter. Om kommunikationen inte fungerar kan en språkbarriär uppstå mellan sjuksköterskor och patient. Då språkbarriärer kan påverka kvaliteten på omvårdnaden är det viktigt att sjuksköterskor kan hantera språkbarriärerna. Genom att använda en tolk kan språkbarriärer hanteras men det finns även brister i användandet av tolk. Syfte: Syftet med studien var att belysa sjuksköterskors erfarenheter av användning av tolk vid språkbarriär. Metod: En kvalitativ litteraturstudie som baserats på 14 vetenskapliga artiklar med kvalitativ ansats. Artiklarna har analyserats med inspiration av Graneheim och Lundmans (2004) samlade beskrivning av innehållsanalys. Resultat: I studiens resultat framkom sju subkategorier: Sjuksköterskors prioriteringar, Sjuksköterskors kunskap om användandet av tolk, Tillgänglighet av formell tolk, Tillgänglighet av informell tolk, Möjligheter vid användning av tolk, Svårigheter vid Sjuksköterskors användning av formell tolk och Svårigheter vid sjuksköterskors användning av informell tolk. Dessa subkategorier resulterade i två huvudkategorier: Sjuksköterskors erfarenheter av att få tillgång till tolk och Sjuksköterskors erfarenheter av användning av tolk. Slutsats: Att sjuksköterskor hade erfarenhet av att tolk var viktigt för att kunna hantera språkbarriärer, det i sin tur gav bättre möjligheter till en god omvårdnad. I sjuksköterskors användning av tolk fanns både möjligheter och svårigheter. I denna studie identifierades en kunskapsbrist i sjuksköterskors användande av tolk. En utbildning i sjuksköterskors användning av tolk ansågs kunna förbättra omvårdnaden vid språkbarriärer.

  • 961.
    Axelsson, Monica
    Blekinge Institute of Technology, Department of Spatial Planning and Civil Engineering.
    Barn och ungdomars behov i den fysiska miljön: skolgårdar i mindre tätorter2003Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [sv]

    SAMMANFATTNING Examensarbetet skildrar hur barn och ungdomar påverkas av den fysiska miljön på skolgårdar samt hur miljön påverkar pedagogik och sociala mönster. Undersökningens främsta syfte är att åskådliggöra vilka utvecklingsriktningar som är aktuella då det gäller förbättringar av skolgårdsmiljöer. Eftersom skolgårdens fysiska utformning även påverkar den sociala miljön, undersöks den fysiska miljöns sammansättning i relation till pedagogiska och sociala behov. Barn och ungdomar vistas på skolgården flera timmar varje dag i många år, därför är det väsentligt att den utemiljö de har att tillgå ger stimulans och rekreation. Dagens debatter handlar till stor del om behovet av att vistas i naturen för att få helhet i undervisningen, träna motorik och kondition, tydliggöra samband samt lära eleverna lyssna till sin intuition. Sådana diskussioner har förts tidigare i historien, men aldrig med sådan uppslutning som nu på 2000-talet. Till skillnad från tidigare debatter verkar det som att berörda parter nu har en gemensam vision om hur de vill att barnen och skolan ska formas. Skolor i små tätorter har ofta större tillgång till naturområden i anslutning till skolan och därmed stora utvecklingsmöjligheter. En resurs som man bör ta vara på. Det har tydligt framgått att t.o.m. små skolgårdsförändringar kan göra stora skillnader i den sociala miljön, och att det även lönar sig ekonomiskt på sikt. I arbetets första del beskrivs olika forskningsresultat och organisationer som haft inverkan på debatter och politiska beslut, samt andra faktorer som bidragit till att skolgårdar ser ut som de gör idag. Där förklaras varför vissa behov måste tillgodoses, samtidigt fungerar materialet som modell för sammanställning av en checklista över viktiga behov på skolgårdar. Del två exemplifierar olika skolgårdsprojekt som är representativa för skoldebattens principer, samt visar hur fyra ordinära skolor i Ronneby kommun tillgodoser elevernas behov med utgångspunkt från en checklista. I samband med det kompletteras checklistan med synpunkter från intervjuer av elever på de aktuella skolorna. I den tredje delen ges slutligen ett utformningsförslag för Hobyskolan, i Bräkne-Hoby, för att illustrera hur en skolgård i en liten tätort kan utformas för att tillgodose barn och ungdomars behov. Viktiga utformningsprinciper för att tillgodose barn och ungdomars behov på skolgårdar är som följer: Skolan behöver en tydlig identitet som ger eleverna struktur och något att vara stolta över. Möjlighet till att genomföra undervisning utomhus, gärna genom någon form av skolträdgård, och/eller experimenterande verksamhet. Eleverna behöver få medverka i skolgårdsprojekt och vara med och bestämma över vad de ska sköta och ansvara för. Få tillgång till platser för kontemplation och avskildhet, möjlighet till att stressa ned och vila huvudet. Gröna stråk i förbindelse med skolans omgivning för att skapa trygga skolvägar och underlätta för motorisk och fysisk aktivitet i angränsande natur. Utökat samarbete med den övriga bygden, låt skolgården få en bredare tillämpning. Frambringa platser för socialt samspel, för vilda respektive lugna lekar samt olika former av mötesplatser.

  • 962.
    Axelsson, Olof
    Blekinge Institute of Technology, School of Planning and Media Design.
    Försäljningsmetoder för spel på Android Market2012Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Smartphones med Android som operativsystem har under de senaste åren blivit en allt större del av vår vardag. Kandidatarbetet undersöker vilken försäljningsmetod man som utvecklare ska använda sig av för att få största möjliga förtjänst, när man säljer ett spel på Androids marknad. De försäljningsmetoder, som studerats, är reklam, prissatt och in app billing. Från insamlad statistik av Google och enkäter har en förståelse kring vilken metod att föredra tagits fram. Resultaten visar att alla fungerar trots deras olikheter sinsemellan. Förslag på hur en blandning av försäljningsmetoderna kan användas och hur man applicerar rätt metod till rätt spel diskuteras och presenteras.

  • 963. Axelsson, Stefan
    The Normalised Compression Distance as a File Fragment Classifier2010In: Digital Investigation. The International Journal of Digital Forensics and Incident Response, ISSN 1742-2876, E-ISSN 1873-202X, Vol. 7, no Suppl 1, p. S24-S31Article in journal (Refereed)
    Abstract [en]

    We have applied the generalised and universal distance measure NCD—Normalised Compression Distance—to the problem of determining the type of file fragments. To enable later comparison of the results, the algorithm was applied to fragments of a publicly available corpus of files. The NCD algorithm in conjunction with the k-nearest-neighbour (k ranging from one to ten) as the classification algorithm was applied to a random selection of circa 3000 512-byte file fragments from 28 different file types. This procedure was then repeated ten times. While the overall accuracy of the n-valued classification only improved the prior probability from approximately 3.5% to circa 32%–36%, the classifier reached accuracies of circa 70% for the most successful file types. A prototype of a file fragment classifier was then developed and evaluated on new set of data (from the same corpus). Some circa 3000 fragments were selected at random and the experiment repeated five times. This prototype classifier remained successful at classifying individual file types with accuracies ranging from only slightly lower than 70% for the best class, down to similar accuracies as in the prior experiment.

  • 964. Axelsson, Stefan
    Using Normalized Compression Distance for Classifying File Fragments2010Conference paper (Refereed)
    Abstract [en]

    We have applied the generalised and universal distance measure NCD-Normalised Compression Distance-to the problem of determining the types of file fragments via example. A corpus of files that can be redistributed to other researchers in the field was developed and the NCD algorithm using k-nearest-neighbour as the classification algorithm was applied to a random selection of file fragments. The experiment covered circa 2000 fragments from 17 different file types. While the overall accuracy of the n-valued classification only improved the prior probability of the class from approximately 6% to circa 50% overall, the classifier reached accuracies of 85%-100% for the most successful file types.

  • 965. Axelsson, Stefan
    et al.
    Baca, Dejan
    Feldt, Robert
    Sidlauskas, Darius
    Kacan, Denis
    Detecting Defects with an Interactive Code Review Tool Based on Visualisation and Machine Learning2009Conference paper (Refereed)
    Abstract [en]

    Code review is often suggested as a means of improving code quality. Since humans are poor at repetitive tasks, some form of tool support is valuable. To that end we developed a prototype tool to illustrate the novel idea of applying machine learning (based on Normalised Compression Distance) to the problem of static analysis of source code. Since this tool learns by example, it is rivially programmer adaptable. As machine learning algorithms are notoriously difficult to understand operationally (they are opaque) we applied information visualisation to the results of the learner. In order to validate the approach we applied the prototype to source code from the open-source project Samba and from an industrial, telecom software system. Our results showed that the tool did indeed correctly find and classify problematic sections of code based on training examples.

  • 966.
    Axelsson, Stefan
    et al.
    Blekinge Institute of Technology, School of Computing.
    Bajwa, Kamran Ali
    Srikanth, Mandhapati Venkata
    Blekinge Institute of Technology, School of Computing.
    File Fragment Analysis Using Normalized Compression Distance2013Conference paper (Refereed)
    Abstract [en]

    The first step when recovering deleted files using file carving is to identify the file type of a block, also called file fragment analysis. Several researchers have demonstrated the applicability of Kolmogorov complexity methods such as the normalized compression distance (NCD) to this problem. NCD methods compare the results of compressing a pair of data blocks with the compressed concatenation of the pair. One parameter that is required is the compression algorithm to be used. Prior research has identified the NCD compressor properties that yield good performance. However, no studies have focused on its applicability to file fragment analysis. This paper describes the results of experiments on a large corpus of files and file types with different block lengths. The experimental results demonstrate that, in the case of file fragment analysis, compressors with the desired properties do not perform statistically better than compressors with less computational complexity.

  • 967.
    Axmon, Anna
    et al.
    Lunds Universitet, SWE.
    Kristensson, Jimmie
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Ahlström, Gerd
    Lunds Universitet, SWE.
    Midlöv, Patrik
    Lunds Universitet, SWE.
    Use of antipsychotics, benzodiazepine derivatives, and dementia medication among older people with intellectual disability and/or autism spectrum disorder and dementia2017In: Research in Developmental Disabilities, ISSN 0891-4222, Vol. 62, p. 50-57Article in journal (Refereed)
    Abstract [en]

    Background Although people with intellectual disability (ID) and people with dementia have high drug prescription rates, there is a lack of studies investigating drug use among those with concurrent diagnoses of ID and dementia. Aim To investigate the use of antipsychotics, benzodiazepine derivatives, and drugs recommended for dementia treatment (anticholinesterases [AChEIs] and memantine) among people with ID and dementia. Methods and procedures Having received support available for people with ID and/or autism spectrum disorder (ASD) was used as a proxy for ID. The ID cohort consisted of 7936 individuals, aged at least 55 years in 2012, and the referent cohort of age- and sex-matched people from the general population (gPop). People with a specialists’ diagnosis of dementia during 2002–2012 were identified (ID, n = 180; gPop, n = 67), and data on prescription of the investigated drugs during the period 2006–2012 were collected. Outcome and results People with ID/ASD and dementia were more likely than people with ID/ASD but without dementia to be prescribed antipsychotics (50% vs 39% over the study period; odds ratio (OR) 1.85, 95% confidence interval 1.13–30.3) and benzodiazepine derivatives (55% vs 36%; OR 2.42, 1.48–3.98). They were also more likely than people with dementia from the general population to be prescribed antipsychotics (50% vs 25%; OR 3.18, 1.59–6.34), but less likely to be prescribed AChEIs (28% vs 45%; OR 0.32, 0.16–0.64).

  • 968.
    Axner, Dr Lilit
    Blekinge Institute of Technology, School of Management.
    HOW TO MAKE ANALYSIS WORK IN BUSINESS INTELLIGENCE SOFTWARE2009Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Competitive Intelligence (CI) has been defined by many authors. These definitions do have certain differences but all of them have a main common feature: They put the accent on the analysis. The most precise definition is given by the Society for Competitive Intelligence Professionals (SCIP): “A systematic and ethical program for gathering, analyzing, and managing external information that can affect your company’s plans, decisions, and operations”. Business Intelligence (BI) is much broader concept than CI. It has rather technical meaning while CI is more about managerial perspective of intelligence. BI includes activities such as data mining, market analysis, sales analysis, and analysis of customer and supplier records and behavior (Bouthillier et al., 2003). However, in some European countries, such as Sweden and Denmark, BI and CI have the similar meaning (Bouthillier et al., 2003). Either way, the main feature of both concepts is the ability to analyze data and information and to deduct intelligence out of them. Currently, a large number of BI and/or CI software is available, and being developed worldwide. A simple search of the “Business Intelligence software” term in Google gives about 548.000 results. Most of these software are quite enhanced and well developed but only a few of them have a good analysis tool, and even fewer give a choice of analysis tools to their users. An extensive work has been done on BI software evaluation by Amara et al. (2009) to classify the top BI software vendors according to the extent of their analysis by using the SSAV (Solberg Söilen, Amara, Vriens) model. A number of analyses for Business Intelligence have been summed up also in Solberg Söilen (2005). The conclusion of both works was the same: BI software need robust analysis tools. In this research we pursue two goals: First we investigate what are the major obstacles for making a better analysis function in the Business Intelligence (BI) software and second we examine how those obstacles can be solved both technically and from a managerial perspective. The intention in this study is to investigate how the analysis module is functioning in the BI software and see how it could be implemented more effectively. This means that the study has two sides one Competitive Intelligence (CI) for the managerial approach and one Business Intelligence (BI) for the more technical approach. First we present a comprehensive literature review and pin point the problems and obstacles defined by many authors. Then we propose a method to solve the identified problems and finally we concentrate on advantages and disadvantages of the proposed method. The proposed technical solution is under construction in the BI software called Subsoft developed by Dr. Klaus Solberg Söilen. We investigate to what extent conclusions here can be used to develop the software further. The managerial perspective of the solutions is explored in close collaboration with two other BI companies: Sentient and Crystalloids, both based in Amsterdam, The Netherlands.

  • 969.
    Axén, Anna
    et al.
    Blekinge Institute of Technology, School of Health Science.
    Svensson, Frida
    Blekinge Institute of Technology, School of Health Science.
    Att som sjuksköterska vårda patienter med ätstörningar2006Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Bakgrund: Sjuksköterskor kan möta patienter med ätstörningar på olika avdelningar. Sjuksköterskor blir ofta överraskade av det stora omvårdnadsbehov som patienterna har. Syfte: Syftet är att belysa sjuksköterskans upplevelser av vården av patienter med ätstörningar. Metod: En litteraturstudie och granskning av sju vetenskapliga artiklar har genomförts, materialet analyserades med inspiration av Graneheims och Lundmans analysmetod. Resultat: Sjuksköterskor tycker inte att de har tillräcklig kunskap och utbildning för att vårda patienter med ätstörningar. Vårdandet leder till blandade känslor hos sjuksköterskan och hon upplever att hon har olika roller i vården. Sjuksköterskorna upplever att relationsskapandet är en viktig del av vården.

  • 970. Axén, Josefin
    et al.
    Hansson, Axel
    Autopia: en undersökning av den kommunala planeringsverksamhetens inställning till autonom mobilitet2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 971.
    Ayalew, Tigist
    et al.
    Blekinge Institute of Technology, School of Computing.
    Kidane, Tigist
    Blekinge Institute of Technology, School of Computing.
    Identification and Evaluation of Security Activities in Agile Projects: A Systematic Literature Review and Survey Study2012Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Context: Today’s software development industry requires high-speed software delivery from the development team. In order to do this, organizations make transformation from their conventional software development method to agile development method while preserving customer satisfaction. Even though this approach is becoming popular development method, from security point of view, it has some disadvantage. Because, this method has several constraints imposed such as lack of a complete overview of a product, higher development pace and lack of documentation. Although security-engineering (SE) process is necessary in order to build secure software, no SE process is developed specifically for agile model. As a result, SE processes that are commonly used in waterfall model are being used in agile models. However, there is a clash or disparity between the established waterfall SE processes and the ideas and methodologies proposed by the agile manifesto. This means that, while agile models work with short development increments that adapt easily to change, the existing SE processes work in plan-driven development setting and try to reduce defects found in a program before the occurrence of threats through heavy and inflexible process. This study aims at bridging the gap in agile model and security by providing insightful understanding of the SE process that are used in the current agile industry. Objectives: The objectives of this thesis are to identify and evaluate security activities from high-profile waterfall SE-process that are used in the current agile industry. Then, to suggest the most compatible and beneficial security activities to agile model based on the study results. Methods: The study involved two approaches: systematic literature review and survey. The systematic literature review has two main aims. The first aim is to gain a comprehensive understanding of security in an agile process model; the second one is to identify high-profile SE processes that are commonly used in waterfall model. Moreover, it helped to compare the thesis result with other previously done works on the area. A survey is conducted to identify and evaluate waterfall security activities that are used in the current agile industry projects. The evaluation criteria were based on the security activity integration cost and benefit provides to agile projects. Results: The results of the systematic review are organized in a tabular form for clear understanding and easy analysis. High-profile SE processes and their activities are obtained. These results are used as an input for the survey study. From the survey study, security activities that are used in the current agile industry are identified. Furthermore, the identified security activities are evaluated in terms of benefit and cost. As a result the best security activities, that are compatible and beneficial, are investigated to agile process model. Conclusions: To develop secure software in agile model, there is a need of SE-process or practice that can address security issues in every phase of the agile project lifecycle. This can be done either by integrating the most compatible and beneficial security activities from waterfall SE processes with agile process or by creating new SE-process. In this thesis, it has been found that, from the investigated high-profile waterfall SE processes, none of the SE processes was fully compatible and beneficial to agile projects.

  • 972. Ayani, Rassul
    et al.
    Ismailov, Yuri
    Liljenstam, Michael
    Popescu, Adrian
    Rajaei, Hassan
    Rönngren, Robert
    Modeling and Simulation of a High Speed LAN1995In: Simulation (San Diego, Calif.), ISSN 0037-5497, E-ISSN 1741-3133, Vol. 64, no 1, p. 7-14Article in journal (Refereed)
    Abstract [en]

    Simulation is a tool that can be used to assess functionality and performance of communication networks and protocols. However, efficient simulation of complex communication systems is not a trivial task. In this paper, we discuss modeling and simulation of bus-based communication networks and present the results of modeling and simulation of a multigigabit/s LAN. We used parallel simulation techniques to reduce the simulation time of the LAN and implemented both an optimistic and a conservative parallel simulation scheme. Our experimental results on a shared memory multiprocessor indicate that the conservative parallel simulation scheme is superior to the optimistic one for this specific application. The parallel simulator based on the conservative scheme demonstates a linear speedup for large networks.

  • 973.
    Ayers, James
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Strategic Sustainable Development.
    Melchert, Gabriel
    Blekinge Institute of Technology, Faculty of Engineering, Department of Strategic Sustainable Development.
    Piwowar, Julius
    Blekinge Institute of Technology, Faculty of Engineering, Department of Strategic Sustainable Development.
    The Impact of Renewable Energy Cooperatives on the Social Resilience of Their Communities2014Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Major global problems, manifested by climate change and social inequality, reinforce the need for a societal shift towards sustainable practices. This transition requires new approaches in the future design of society. The current energy system, based on fossil fuels and centralized infrastructure is a key contributor to many of the socio-ecological issues related to the sustainability challenge. The intent of this research is to examine renewable energy cooperatives as an alternative to minimize the negative impacts of the current energy system. Using a Strategic Sustainable Development (SSD) approach with a Resilience Attribute Framework, this research explored the presence of resilience attributes (Trust, Diversity, Learning and Self-organization) and sustainability behavior in renewable energy cooperatives. The research then explored, through interview and surveys, the perceived impacts that these cooperatives had on the resilience and sustainability behavior of the wider community. Findings showed that energy cooperatives displayed high levels of the resilience through the attributes of: - Trust: due to non-profit status, ownership structure, localisation and shared values - Diversity: due to member and service diversity - Learning: through collaboration, diverse member knowledge and participation - Self-organization: due to cooperative development, leadership and outcomes (infrastructure and energy knowledge). This study showed that renewable energy cooperatives have numerous impacts on their community however; there were no significant evidence to suggest energy cooperatives transferred their high levels of social resilience to the community.

  • 974.
    Ayichiluhm, Theodros
    et al.
    Blekinge Institute of Technology, School of Computing.
    Mohan, Vivek
    Blekinge Institute of Technology, School of Computing.
    IPv6 Monitoring and Flow Detection2013Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    IPv6 Privacy extensions, implemented in major operating systems, hide user’s identity by using a temporary and a randomly generated IPv6 addresses rather than using the former, EUI-64 format where the MAC address is part of the IPv6 address. This solution for privacy has created a problem for network administrators to back-trace an IPv6 address to a specific MAC address, since the temporary IP address used once by the node is removed from the interface after a period of time. An IPv6 Ethernet test bed is setup to investigate IPv6 implementation dynamics in Windows 7 and Ubuntu10.04 operating systems. The testbed is extended to investigate the effects of temporary IPv6 addresses due to IPv6 privacy extensions on the on-going sessions of different applications including ping, File Transfer Protocol (FTP) and video streaming (HTTP and RTP). On the basis of the knowledge obtained from investigations about dynamics of IPv6 privacy extensions, this work proposes Internet Protocol version 6 Host Tracking (IPv6HoT), a web based IPv6 to MAC mapping solution. IPv6HoT uses Simple Network Management Protocol (SNMP) to forward IPv6 Neighbor table from routers to Network Management Stations (NMS). This thesis work provides guidelines for configuring IPv6 privacy extensions in Ubuntu10.04 and Windows 7; the difference of implementation between these two operating systems is also presented in this work. The results show that temporary IPv6 addressing has a definite effect on the on-going sessions of video streaming and FTP applications. Applications running as server on Temporary IPv6 address encountered more frequent on-going session interruptions than applications running as a server over public IPv6 address. When temporary IPv6 addresses were configured to host FTP and video streaming applications, their on-going sessions were permanently interrupted. It is also observed that LFTP, a client FTP application, resumes an interrupted session.

  • 975.
    Ayisha, Alhassan
    et al.
    Blekinge Institute of Technology, Faculty of Health Sciences, Department of Health.
    Jammeh, Binta
    Blekinge Institute of Technology, Faculty of Health Sciences, Department of Health.
    Personers upplevelse av att leva med ett nytt hjärta: en litteraturstudie2014Student thesis
    Abstract [en]

    Bakgrund: Allt fler människor lever idag med ett nytt hjärta. Hjärttransplantation kan väcka många tankar, känslor och funderingar som personer kan uppleva vara svåra att hantera. Det är viktigt att personen får ett gott stöd för att kunna hanterade det nya livet efter hjärttransplantationen. Syfte: Syftet med studien var att belysa personers upplevelser av att leva med ett nytt hjärta under de första tio åren efter genomgången transplantation. Metod: Studien genomfördes som en litteraturstudie med kvalitativ ansats baserad på sex vetenskapliga artiklar som analyserats med kvalitativ innehållsanalys. Resultat: I resultatet framkom tre kategorier av upplevelser: Livet går vidare, Blandade känslor och Viktigt med stöd. Resultatet visade att hjärttransplantation innebär en stor omställning för personen. Personernas vardag präglades av många olika upplevelser, såväl positiva som negativa. Personerna var i behov av ett gott stöd då det ligger till grund för deras anpassning till det nya livet efter hjärttransplantationen. De personer som fick en god stöttning upplevde bland annat ökad självkänsla, tillfredsställelse med livet och ökat välbefinnande. Däremot hade personer med sämre stöttning större benägenhet att drabbas av oro och depressioner. Slutsats: Litteraturstudien visar att personer som genomgått en hjärttransplantation och lever med ett nytt hjärta upplever detta som att få en andra chans i livet. Personerna upplevde vidare att deras vardag präglades av många olika upplevelser, såväl positiva som negativa. Stödet av vårdteamet, familjen och vänner var av stor betydelse för anpassningen till det nya livet efter hjärttransplantationen, tron på Gud var också till stor hjälp. Det är viktigt att sjuksköterskan kan se utifrån personens levda värld för att ur ett livsvärldsperspektiv kunna stödja och vägleda denne i det nya livet efter hjärttransplantationen.

  • 976.
    Ayoubi, Tarek
    Blekinge Institute of Technology, School of Engineering, Department of Interaction and System Design.
    Distributed Data Management Supporting Healthcare Workflow from Patients’ Point of View2007Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Patient’s mobility throughout his lifetime leaves a trial of information scattered in laboratories, clinical institutes, primary care units, and other hospitals. Hence, the medical history of a patient is valuable when subjected to special healthcare units or undergoes home-care/personal-care in elderly stage cases. Despite the rhetoric about patient-centred care, few attempts were made to measure and improve in this arena. In this thesis, we will describe and implement a high-level view of a Patient Centric information management, deploying at a preliminary stage, the use of Agent Technologies and Grid Computing. Thus, developing and proposing an infrastructure that allows us to monitor and survey the patient, from the doctor’s point of view, and investigate a Persona, from the patients’ side, that functions and collaborates among different medical information structures. The Persona will attempt to interconnect all the major agents (human and software), and realize a distributed grid info-structure that directly affect the patient, therefore, revealing an adequate and cost-effective solution for most critical information needs. The results comprehended in the literature survey, consolidating Healthcare Information Management with emerged intelligent Multi-Agent System Technologies (MAS) and Grid Computing; intends to provide a solid basis for further advancements and assessments in this field, by bridging and proposing a framework between the home-care sector and the flexible agent architecture throughout the healthcare domain.

  • 977.
    Ayoubi, Tarek
    et al.
    Blekinge Institute of Technology, School of Management.
    Acuna, Francisco
    Blekinge Institute of Technology, School of Management.
    Sustainable Equity Fund Investments within Latin America– case of Indigenous People2011Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Sustainable development has been a popular sentiment among those in the international development field for many years. Sustainable development refers not only to environmental conservation, but responsible social initiatives as well especially as it relates to minority groups such as indigenous peoples. The players concerned have conventionally involved local and national governments, multilateral organizations, and various NGOs. Increasingly, the private sector has become engaged in this area as well. Our study shows that now, more than ever, there is a need and opportunity for ethical funds in Latin America and other emerging markets dedicated for the indigenous people. We address the challenges and opportunities to create a new model of investment in emerging markets and concretely with indigenous peoples under a sustainable model, including clean energy production.

  • 978.
    Ayub, Hasan
    et al.
    Blekinge Institute of Technology, School of Engineering.
    Awan, Shoaib Shafiq
    Blekinge Institute of Technology, School of Engineering.
    QoS and Integrating issues of Real Time Traffic within Wireless Environment2009Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Wireless technology in simple words is a technique that enables more than one user to share resources without having wiring. In comparison with wired local area network in which twisted pair cables, adapters and coaxial cables are used to connect multiple devices. Wireless technology has enabled us to send and receive data through radio and infrared waves and a single access point in WLAN can easily accommodate many users in the same domain. In this era of technology we want everything to be simplified to the maximum and in regards to wireless technology we want to have voice over IP instead of analog phones this is what we call real time traffic. In this Thesis report we have studied the WLAN technology in detail with special emphasis on QoS issues and tried to suggest the possibilities on how to integrate real time traffic on WLAN. Through simulation we will try to find improvements in this field. Our main focus will be on CSMA/CA protocol of 802.11 and 802.11e standards, and different MAC schemes that are used to accommodate different types of traffic, special emphasis is given on DCF and EDCA. Through simulation we will show the results that how these fields can affect the QoS of WLAN, these schemes enables more user capacity which means that we can increase the traffic and make wireless LAN more adaptive. The simulation that we will do in this Thesis will be totally correlated with our research but it will not be practically implemented.

  • 979.
    Ayub, Muhammad
    Blekinge Institute of Technology, School of Engineering, Department of Mathematics and Natural Sciences.
    Choquet and Sugeno Integrals2009Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    In real word many problems, most of criteria have interdependent or interactive characteristics, which cannot be evaluated by additive measures exactly. For the human subjective evaluation processes it will be more better to apply Choquet and Sugeno integrals model together with the definition of lambda − fuzzy measure, in which the property of additivity is not necessary. My thesis presents the application of fuzzy integrals as tool for criteria aggregation in the decision problems. Finally, this research gives the examples of evaluating medicine with illustrations of hierarchicalstructure of lambda− fuzzy measure for Choquet and Sugeno integrals model.

  • 980.
    Ayub, Yasir
    et al.
    Blekinge Institute of Technology, School of Computing.
    Faruki, Usman
    Blekinge Institute of Technology, School of Computing.
    Container Terminal Operations Modeling through Multi agent based Simulation2009Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    This thesis aims to propose a multi-agent based hierarchical model for the operations of container terminals. We have divided our model into four key agents that are involved in each sub processes. The proposed agent allocation policies are recommended for different situations that may occur at a container terminal. A software prototype is developed which implements the hierarchical model. This web based application is used in order to simulate the various processes involved in the following operations on the marine side in a case study of a container terminal in Sweden by adopting a multi-agent based simulation technique. Due to the increase in usage of container transportation, container terminals are experiencing difficulties in the management of the operations. The software provides a decision support capability to terminal managers for scheduling and managing the operations effectively while also visually presenting the time it takes to complete the process and its associated cost. Terminal managers need to implement certain policies to improve the management and operations of the container terminal. The policies are evaluated and tested under various cases to provide a more comparative overview. The results of the simulation experiments indicate that the waiting time for arriving vessels is decreasing when in queue with more than three vessels arriving on same day.

  • 981.
    Ayyagari, Nitin Reddy
    Blekinge Institute of Technology, Faculty of Computing, Department of Communication Systems.
    Databases For Mediation Systems: Design and Data scaling approach2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Context: There is continuous growth in data generation due to wide usage of modern communication systems. Systems have to be designed which can handle the processing of these data volumes efficiently. Mediation systems are meant to serve this purpose. Databases form an integral part of the mediation systems. Suitability of the databases for such systems is the principle theme of this work.

    Objectives: The objective of this thesis is to identify the key requirements for databases that can be used as part of Mediation systems, gain a thorough understanding of various features, the data models commonly used in databases and to benchmark their performance.

    Methods: Previous work that has been carried out on various databases is studied as a part of literature review. Test bed is set up as a part of experiment and performance metrics such as throughput and total time taken were measured through a Java based client. Thorough analysis has been carried out by varying various parameters like data volumes, number of threads in the client etc.

    Results: Cassandra has a very good write performance for event and batch operations. Cassandra has a slightly better read performance when compared to MySQL Cluster but this differentiation withers out in case of fewer number of threads in the client.

    Conclusions: On evaluation of MySQL Cluster and Cassandra we conclude that they have several features that are suitable for mediation systems. On the other hand, Cassandra does not guarantee ACID transactions while MySQL Cluster has good support. There is need for further evaluation on new generation databases which are not mature enough as of now.

  • 982.
    Azam, Abdallah
    Blekinge Institute of Technology, School of Planning and Media Design.
    Boendeformer och segregation: En undersökning om relationen mellan politiska ambitioner, planering och forskning2012Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [sv]

    Boendesegregationsfrågan har under de senaste åren fått en allt större uppmärksamhet. Den negativa samhällsutvecklingen i samband med koncentrationen av fattiga invånare och minoritetsgrupper i vissa bostadsområden väckte även intresset för grannskapseffekter. När effekterna blir negativa för de boende blir det genast befogat att finna lösningar för att åtgärda problemen. Det har under årens gång därför riktats satsningar mot de utsatta områdena för att motverka boendesegregationen och dess effekter, en typ av satsning som senare fått motstå mycket kritik. Idag råder det en allmän samsyn bland politiker, beslutsfattare och planerare om att boendesegregationsproblematiken kan åtgärdas om de socialt utsatta områdena blir mer socialt blandade. För att uppnå blandningen förespråkas därför ett allsidigt bostadsbyggande, dvs. en blandning av boende- och upplåtelseformer, i stadens alla delar. Detta eftersom politiska partier och kommuner tenderar att se boendesegregationen som en effekt av den fysiska strukturen och det homogena bostadsbeståndet som karaktäriserar vissa områden. Syftet med examensarbetet är därmed att undersöka och redogöra för interaktionen mellan politiska ambitioner, planeringsprocess och forskning genom att analysera den vetenskapliga förankringen av föreställningen om boendeformer som medel för att motverka boendesegregationen i samhället. Undersökningen görs eftersom föreställningen kan liknas vid den s.k. rumsliga determinismen som bygger på en tilltro till att fysiska förändringar på ett avgörande sätt kan förändra och påverka det sociala livet. Flertalet forskare vänder sig mot denna föreställning och hävdar att problemen inte ligger i grannskapen, utan är strukturella och påträffas i bl.a. arbets- och bostadsmarknad, utbildning och näringsliv. Andra hävdar dessutom att den sociala blandningen kan få kontraproduktiva följder eftersom det ligger i människans natur att söka sig till relativt små sociala avstånd i omgivningen. Ambitionen med denna rapport är att bidra till en ökad förståelse av relationen mellan politiska intentioner, planeringsprocess och forskning samt bidra till en omvärdering av den allmänt förespråkade föreställningen om att boende- och upplåtelseformer motverkar boendesegregationen i samhället.

  • 983.
    Azam, Abdallah
    Blekinge Institute of Technology, School of Planning and Media Design.
    Gjuteriet: Ett planförslag med hänsyn till det kulturhistoriska arvet2010Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Sammanfattning Malmö är idag i en övergångsfas från att ha varit ett industrisamhälle till att bli ett kunskapssamhälle. En sådan övergång leder till att industrierna måste ge plats åt kunskapsföretagen. I samband med dessa industrier i före detta profilerade industristäder som Malmö finns ett stort kulturhistoriskt värde förknippat. Att omvandla kulturhistoriska områden utan att inskränka på dess historiska värde är inte alltid lätt. Därför har regeringen arbetat fram det kulturpolitiska målet där termen kulturmiljövård introducerades som ett samlande begrepp för att bevara och levandegöra kulturarvet samt kunna spegla samhällets och inte minst industrialismens historia. Arbetet har utifrån detta studerat kulturmiljöbegreppet för att sedan göra ett funktionsomvandlingsförslag för kvarteret Gjuteriet i Malmö där Ljungmans verkstäder bedrev sin verksamhet förr med hänsyn till platsens historiska värde. Syftet med arbetet har därmed varit att göra en karaktärisering av kvarteret Gjuteriet i Malmö för att sedan upprätta ett förslag för vilka byggnader som skall bevaras och med hänsyn till dessa byggnaders kulturhistoriska värde bryta upp detta jättekvarter till mindre stadskvarter. Därefter ta fram riktlinjer för området för att sedan bestämma markanvändningen samt ta fram ett förslag på hur kommande exploatering inom området kan utformas.

  • 984.
    Azam, Adnan
    et al.
    Blekinge Institute of Technology, School of Engineering.
    Siddique, Taimoor
    Blekinge Institute of Technology, School of Engineering.
    Spectrum Optimization in Cognitive Radio Networks using Genetic Algorithms2010Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    The rapid revolution in wireless communication in past years has increased the demand of radio spectrum to fulfill quality of service (QoS) requirements of wireless applications, leading to spectrum overcrowding. To solve the spectrum overcrowding problem, cognitive radio (CR) has emerged as a leading technology because it can intelligently sense an unused spectrum without creating any harm to authorized users. Once the spectrum is sensed, to fulfill QoS requirement of the application and to utilize the radio resources more efficiently, an intelligent decision to allocate an optimum spectrum is a prime requirement. In this thesis work a spectrum allocation procedure is proposed. Genetic Algorithms (GA) an evolutionary computational technique is used which works on Darwin theory of evolution. It defines the radio in the form of chromosomes and genes. The procedure is modeled using Matlab, and the application’s QoS requirements are given as input to the GA procedure, which results in an optimum solution after several evolution

  • 985.
    Azam, Muhammad
    Blekinge Institute of Technology, School of Engineering.
    Methods for Recovery of Missing Speech Packets2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    In packetized voice communication, speech packets are sometimes lost due to data transmission problems, e.g., signal fading, or interfering users and noise. For the recovery of missing speech packets, different methods are proposed. This thesis analyzes some recovery methods, and four variants of a waveform substitution method used during the objective analysis. This method is based on slow varying speech parameter estimates. These parameters include the short time energy (STE) and the zero crossing (ZC) measure. This technique is implemented in two different ways based on the slow varying parameters. These parameters are stored in the previous packet. If a speech packet is lost, it is recovered by the information stored in the previous packets. Both implementations differ only in the use of the zero crossing information. The short time energy estimation is the same in both implementations. A slight modification is made in these two implementations where the estimated speech parameters are stored in the previous and in future packets in order to recover two consecutive packets. This modification is applied only if the speech signal is already saved at the transmitter because it requires the future packets to store the information of previous packets, i.e., a non-causal solution. However, a causal solution is obtained if the signal is allowed to be delayed by one packet. The speech quality of the reconstructed speech signal is analyzed and compared between the four implementations. The implementation of these methods has been validated by subjectively observing the recovered speech packets, and by considering the improvement of the objective measures mean opinion score (MOS), mean square error (MSE) and signal-to-noise ratio (SNR). The recovery of samples within the packets is also discussed. The recovery of samples within a packet is done by the Fast Fourier Transform (FFT) block code method. The FFT block code method is implemented by an iterative algorithm. This method is validated by subjective observations and improvements in objective measures mean square error (MSE) and signal to noise ratio (SNR). The VAD is also used for the waveform substitution method and in the introduction of channel noise. After subjective observations and objective measures, it is concluded that modified method A provides better performance for the recovery of speech packets and the FFT block code method has been validated for recovering the samples within a packet.

  • 986.
    Azam, Muhammad
    et al.
    Blekinge Institute of Technology, School of Computing.
    Ahmad, Luqman
    Blekinge Institute of Technology, School of Computing.
    A Comparative Evaluation of Usability for the iPhone and iPad2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Many everyday systems and products seem to be designed with little regard to usability. This leads to the frustration, wasted time and errors. So the usability of the product is important for its survival in the market. In many previous studies the usability evaluation of the iPhone and iPad carried out individually and very little work has been done on the comparative usability evaluation. However, there was not any study conducted on the comparative usability evaluation and measuring the performance of the iPhone versus iPad in a controlled environment. In this research work, the authors performed the comparative usability evaluation and measured the performances of the iPhone and iPad on the selected applications by considering the young users as well as the elderly users. Another objective of this study is to identify the usability issues in performances of the iPhone and iPad. A survey and experiment techniques were used to achieve the dened objectives. The survey questionnaire consisted of 42 statements that presented the different usability aspects. The objectives of the survey study were to validate the identified issues from the literature study, identify new issues and measure the signicant difference in user opinions for the iPhone and iPad. However, the experiment studies helped to measure the performance significances between the devices against the three user groups (novice user, experienced user, elderly user) and among the groups over the devices. Further, objective was to measure the satisfaction level of the participated users against the iPhone and iPad. The experiment was performed in a controlled environment. Total six tasks (two tasks per application) were dened and each participant performed the same task on both devices. Generally the authors found that the participants performed better on the iPad with lower error rates as compare to the iPhone.

  • 987.
    Azam, Muhammad
    et al.
    Blekinge Institute of Technology, School of Computing.
    Hussain, Izhar
    Blekinge Institute of Technology, School of Computing.
    The Role of Interoperability in eHealth2009Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    In the light of challenges the lack of interoperability in systems and services has long been recognized as one of the major challenge to the wider implementation of the eHealth applications. The opportunities and positive benefits of achieving interoperability are eventually considerable, whereas various barriers and challenges act as impediments. The purpose of this study was to investigate the interoperability among different health care organizations. The knowledge of this study would be supportive to health care organizations to understand the interoperability problems in health care organizations. In the first phase of literature review interoperability challenges in Sweden and other EU countries were identified. On the basis of findings interviews were conducted to know the strategies and planning about interoperability in health care organizations. After analysis of interviews, questionnaires were conducted to know the opinions of different medical IT administrator and health professionals. The authors find after the analysis of interviews and questionnaire that adopting eHealth standard, same system, insuring the security of patient’s health record information and same medical language could be implemented in Sweden and other EU countries health organizations.

  • 988. Azhar, Damir
    et al.
    Riddle, Patricia
    Mendes, Emilia
    Blekinge Institute of Technology, School of Computing.
    Mittas, Nikolaos
    Angelis, Lefteris
    Using ensembles for web effort estimation2013Conference paper (Refereed)
    Abstract [en]

    Background: Despite the number of Web effort estimation techniques investigated, there is no consensus as to which technique produces the most accurate estimates, an issue shared by effort estimation in the general software estimation domain. A previous study in this domain has shown that using ensembles of estimation techniques can be used to address this issue. Aim: The aim of this paper is to investigate whether ensembles of effort estimation techniques will be similarly successful when used on Web project data. Method: The previous study built ensembles using solo effort estimation techniques that were deemed superior. In order to identify these superior techniques two approaches were investigated: The first involved replicating the methodology used in the previous study, while the second approach used the Scott-Knott algorithm. Both approaches were done using the same 90 solo estimation techniques on Web project data from the Tukutuku dataset. The replication identified 16 solo techniques that were deemed superior and were used to build 15 ensembles, while the Scott-Knott algorithm identified 19 superior solo techniques that were used to build two ensembles. Results: The ensembles produced by both approaches performed very well against solo effort estimation techniques. With the replication, the top 12 techniques were all ensembles, with the remaining 3 ensembles falling within the top 17 techniques. These 15 effort estimation ensembles, along with the 2 built by the second approach, were grouped into the best cluster of effort estimation techniques by the Scott-Knott algorithm. Conclusion: While it may not be possible to identify a single best technique, the results suggest that ensembles of estimation techniques consistently perform well even when using Web project data

  • 989.
    Azhar, Muhammad Saad Bin
    et al.
    Blekinge Institute of Technology, School of Computing.
    Aslam, Ammad
    Blekinge Institute of Technology, School of Computing.
    Multiple Coordinated Information Visualization Techniques in Control Room Environment2009Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Presenting large amount of Multivariate Data is not a simple problem. When there are multiple correlated variables involved, it becomes difficult to comprehend data using traditional ways. Information Visualization techniques provide an interactive way to present and analyze such data. This thesis has been carried out at ABB Corporate Research, Västerås, Sweden. Use of Parallel Coordinates and Multiple Coordinated Views was has been suggested to realize interactive reporting and trending of Multivariate Data for ABB’s Network Manager SCADA system. A prototype was developed and an empirical study was conducted to evaluate the suggested design and test it for usability from an actual industry perspective. With the help of this prototype and the evaluations carried out, we are able to achieve stronger results regarding the effectiveness and efficiency of the visualization techniques used. The results confirm that such interfaces are more effective, efficient and intuitive for filtering and analyzing Multivariate Data.

  • 990.
    Aziz, Faisal
    Blekinge Institute of Technology, School of Management.
    Contextual Analysis of IT-Business Alignment2011Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    IT-Business alignment is an imperative process in the success of any business to use the competitive advantage of the information technology. In this work, influence of contextual information on IT-Business alignment has been studied. For this purpose, a conceptual model has been proposed which considers the IT-Business alignment model and national culture as contextual information. For alignment model, strategic alignment maturity model (SAMM) by Luftmann has been used while Hofstede’s model has been followed for the analysis of national culture. Conceptual model considers the 6 maturity assessment elements and analyzes them in the perspective of 4 national cultural factors. Survey methodology has been employed with questionnaire technique to compute the SAMM elements. National cultural scores have been obtained from the empirical study of Hofstede. Empirical results of SAMM elements and cultural factors have been used to support the analysis of the conceptual model.

  • 991.
    Aziz, Hussein
    Blekinge Institute of Technology, School of Computing.
    Streaming Video over Unreliable and Bandwidth Limited Networks2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The main objective of this thesis is to provide a smooth video playout on the mobile device over wireless networks. The parameters that specify the wireless channel include: bandwidth variation, frame losses, and outage time. These parameters may affect the quality of the video negatively, and the mobile users may notice sudden stops during the playout video, i.e., the picture is momentarily frozen, followed by a jump from one scene to a different one. This thesis focuses on eliminating frozen pictures and reducing the amount of video data that need to be transmitted. In order to eliminate frozen scenes on the mobile screen, we propose three different techniques. In the first technique, the video frames are split into sub-frames; these sub-frames are streamed over different channels. In the second technique the sub-frames will be “crossed” and sent together with other sub-frames that are from different positions in the streaming video sequence. If some sub-frames are lost during the transmission a reconstruction mechanism will be applied on the mobile device to recreate the missing sub-frames. In the third technique, we propose a Time Interleaving Robust Streaming (TIRS) technique to stream the video frames in different order. The benefit of that is to avoid losing a sequence of neighbouring frames. A missing frame from the streaming video will be reconstructed based on the surrounding frames on the mobile device. In order to reduce the amount of video data that are streamed over limited bandwidth channels, we propose two different techniques. These two techniques are based on identifying and extracting a high motion region of the video frames. We call this the Region Of Interest (ROI); the other parts of the video frames are called the non-Region Of Interest (non-ROI). The ROI is transmitted with high quality, whereas the non-ROI is interpolated from a number of references frames. In the first technique the ROI is a fixed size region; we considered four different types of ROI and three different scenarios. The scenarios are based on the position of the reference frames in the streaming frame sequence. In the second technique the ROI is identified based on the motion in the video frames, therefore the size, position, and shape of the ROI will be different from one video to another according to the video characteristic. The videos are coded using ffmpeg to study the effect of the proposed techniques on the encoding size. Subjective and objective metrics are used to measure the quality level of the reconstructed videos that are obtained from the proposed techniques. Mean Opinion Score (MOS) measurements are used as a subjective metric based on human opinions, while for objective metric the Structural Similarity (SSIM) index is used to compare the similarity between the original frames and the reconstructed frames.

  • 992. Aziz, Hussein Muzahim
    Enhancing the Smoothness of Streaming Video for Mobile Users over Unreliable Networks2010Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Real time video streaming over wireless network is an increasingly important and attractive service to the mobile users. Video streaming involves a large amount of data to be transmitted in real time, while wireless channel conditions may vary from time to time. It is hard to guarantee a reliable transmission over the wireless network, where the parameters specifying the transmissions are; bandwidth, packet loss, packet delays, and outage times. The quality of the video is affected negatively when network packets are lost, and the mobile users may notice some sudden stop during the video playing; the picture is momentarily frozen, followed by a jump from one scene to a totally different one. The main objective of this thesis is to provide a smooth video playback in the mobile device over unreliable networks with a satisfactory video quality. Three different techniques are proposed to achieve this goal. The first technique will stream duplicate gray scale frames over multichannels, if there is lost frames in one channel it can be recovered from another channel. In the second technique, each video frame will be split into sub-frames. The splitted sub-frames will be streamed over multichannels. If there is a missing sub-frame during the transmission a reconstruction mechanism will be applied in the mobile device to recreate the missing sub-frames. In the third technique, we propose a time interleaving robust streaming (TIRS) technique to stream the video frames in different order. The benefit of that is to avoid the losses of a sequence of neighbouring frames. A missing frame from the streaming video will be reconstructed based on the surrounding frames. The mean opinion score (MOS) metric is used to evaluate the video quality. The experienced quality of a video is subject to the personal opinion, which is the only goal to satisfy the average human watching the contents of the video.

  • 993.
    Aziz, Hussein Muzahim
    et al.
    Blekinge Institute of Technology, School of Computing.
    Fiedler, Markus
    Blekinge Institute of Technology, School of Computing.
    Grahn, Håkan
    Blekinge Institute of Technology, School of Computing.
    Lundberg, Lars
    Blekinge Institute of Technology, School of Computing.
    Compressing Video Based on Region of Interest2013Conference paper (Refereed)
    Abstract [en]

    Real-time video streaming suffer from bandwidth limitation that are unable to handle the high amount of video data. To reduce the amount of data to be streamed, we propose an adaptive technique to crop the important part of the video frames, and drop the part that are outside the important part; this part is called the Region of Interest (ROI). The Sum of Absolute Differences (SAD) is computed to the consecutive video frames on the server side to identify and extract the ROI. The ROI are extracted from the frames that are between reference frames based on three scenarios. The scenarios been designed to position the reference frames in the video frames sequence. Linear interpolation is performed from the reference frames to reconstruct the part that are outside the ROI on the mobile side. We evaluate the proposed approach for the three scenarios by looking at the size of the compressed videos and measure the quality of the videos by using the Mean Opinion Score (MOS). The results show that our technique significantly reduces the amount of data to be streamed over wireless networks with acceptable video quality are provided to the mobile viewers.

  • 994. Aziz, Hussein Muzahim
    et al.
    Fiedler, Markus
    Blekinge Institute of Technology, School of Computing.
    Grahn, Håkan
    Blekinge Institute of Technology, School of Computing.
    Lundberg, Lars
    Blekinge Institute of Technology, School of Computing.
    Eliminating the Effects of Freezing Frames on User Perceptive by Using a Time Interleaving Technique2012In: Multimedia Systems, ISSN 0942-4962, E-ISSN 1432-1882, Vol. 18, no 3, p. 251-262Article in journal (Refereed)
    Abstract [en]

    Streaming video over a wireless network faces several challenges such as high packet error rates, bandwidth variations, and delays, which could have negative effects on the video streaming and the viewer will perceive a frozen picture for certain durations due to loss of frames. In this study, we propose a Time Interleaving Robust Streaming (TIRS) technique to significantly reduce the frozen video problem and provide a satisfactory quality for the mobile viewer. This is done by reordering the streaming video frames as groups of even and odd frames. The objective of streaming the video in this way is to avoid the losses of a sequence of neighbouring frames in case of a long sequence interruption. We evaluate our approach by using a user panel and mean opinion score (MOS) measurements; where the users observe three levels of frame losses. The results show that our technique significantly improves the smoothness of the video on the mobile device in the presence of frame losses, while the transmitted data are only increased by almost 9% (due to reduced time locality).

  • 995. Aziz, Hussein Muzahim
    et al.
    Fiedler, Markus
    Grahn, Håkan
    Lundberg, Lars
    Streaming Video as Space – Divided Sub-Frames over Wireless Networks2010Conference paper (Refereed)
    Abstract [en]

    Real time video streaming suffers from lost, delayed, and corrupted frames due to the transmission over error prone channels. As an effect of that, the user may notice a frozen picture in their screen. In this work, we propose a technique to eliminate the frozen video and provide a satisfactory quality to the mobile viewer by splitting the video frames into sub- frames. The multiple descriptions coding (MDC) is used to generate multiple bitstreams based on frame splitting and transmitted over multichannels. We evaluate our approach by using mean opinion score (MOS) measurements. MOS is used to evaluate our scenarios where the users observe three levels of frame losses for real time video streaming. The results show that our technique significantly improves the video smoothness on the mobile device in the presence of frame losses during the transmission.

  • 996. Aziz, Hussein Muzahim
    et al.
    Grahn, Håkan
    Lundberg, Lars
    Eliminating the Freezing Frames for the Mobile User over Unreliable Wireless Networks2009Conference paper (Refereed)
    Abstract [en]

    The main challenge of real time video streaming over a wireless network is to provide good quality service (QoS) to the mobile viewer. However, wireless networks have a limited bandwidth that may not be able to handle the continues video frame sequence and also with the possibility that video frames could be dropped or corrupted during the transmission. This could severely affect the video quality. In this study we come up with a mechanism to eliminate the frozen video and provide a quality satisfactory for the mobile viewer. This can be done by splitting the video frames to sub-frame and transmitted over multiple channels. We will present a subjective test, the Mean Opinion Score (MOS). MOS is used to evaluate our scenarios where the users can observe three levels of frame losses for real time video streaming. The results for our technique significantly improves the indicate perceived that video quality.

  • 997. Aziz, Hussein Muzahim
    et al.
    Grahn, Håkan
    Lundberg, Lars
    Sub-Frame Crossing for Streaming Video over Wireless Networks2010Conference paper (Refereed)
    Abstract [en]

    Transmitting a real time video streaming over a wireless network cannot guarantee that all the frames could be received by the mobile devices. The characteristics of a wireless network in terms of the available bandwidth, frame delay, and frame losses cannot be known in advanced. In this work, we propose a new mechanism for streaming video over a wireless channel. The proposed mechanism prevents freezing frames in the mobile devices. This is done by splitting the video frame in two sub-frames and combines them with another sub-frame from different sequence position in the streaming video. In case of lost or dropped frame, there is still a possibility that another half (sub-frame) will be received by the mobile device. The receiving sub-frames will be reconstructed to its original shape. A rate adaptation mechanism will be also highlight in this work. We show that sever can skip up to 50% of the sub-frames and we can still be able to reconstruct the receiving sub-frame and eliminate the freezing picture in the mobile device.

  • 998. Aziz, Hussein Muzahim
    et al.
    Lundberg, Lars
    Graceful degradation of mobile video quality over wireless network2009Conference paper (Refereed)
    Abstract [en]

    Real-time video transmission over wireless channels has become an important topic in wireless communication because of the limited bandwidth of wireless network that should handle high amount of video frames. Video frames must arrive at the client before the playout time with enough time to display the contents of the frames. Real-time video transmission is particularly sensitive to delay as it has a strict bounded end-to-end delay constraint; video applications impose stringent requirements on communication parameters, such as frame lost and frame dropped due to excessive delay are the primary factors affecting the user-perceived quality. In this study we investigate ways of obtaining a graceful and controlled degradation of the quality, by introducing redundancy in the frame sequence and compensating this by limiting colourcoding and resolution. The effect of that is to use double streaming mechanism, in this way we will obtain less freezing at the expense of limited colours and resolution. Our experiments, applied to scenarios where users can observe three types of dropping load for real time video streaming, the analytical measurements tools are used in this study to evaluate the video quality is the mean opinion score and we will demonstrate this and argue that the proposed technique improves the use perceived of the video quality.

  • 999. Aziz, Maryam
    et al.
    Masum, M. E.
    Babu, M. J.
    Rahman, Suhaimi Ab
    Nordberg, Jörgen
    Blekinge Institute of Technology, School of Computing.
    Mobility impact on the end-to-end delay performance for VoIP over LTE2012In: Procedia Engineering, Coimbatore: Elsevier , 2012, Vol. 30, p. 491-498Conference paper (Refereed)
    Abstract [en]

    Long Term Evolution (LTE) is the last step towards the 4th generation of cellular networks. This revolution is necessitated by the unceasing increase in demand for high speed connection on LTE networks. This paper focuses on the performance evaluation of End-to-End delay under variable mobility speed for VoIP (Voice over IP) in the LTE network. In the course of E2E performance evaluation, realizing simulation approach three scenarios have been modeled using OPNET 16.0. The first one is the baseline network while among other two, one consists of VoIP traffic solely and the other consists of FTP along with VoIP. E2E delay has been measured for both scenarios in various cases under the varying mobility speed of the node. Simulation results have been studied and presented in terms of comparative performance analysis of the three network scenarios. In light of the result analysis, the performance quality of a VoIP network (with and without the presence of additional network traffic) in LTE has been determined and discussed. The simulation results for baseline VoIP network (non-congested) congested VoIP network and congested VoIP with FTP network show that as the speed of node is gradually increased, E2E delay slightly increases.

  • 1000.
    Aziz, Md. Tariq
    et al.
    Blekinge Institute of Technology, School of Computing.
    Islam, Mohammad Saiful
    Blekinge Institute of Technology, School of Computing.
    Performance Evaluation of Real–Time Applications over DiffServ/MPLS in IPv4/IPv6 Networks2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Over the last years, we have witnessed a rapid deployment of real-time applications on the Internet as well as many research works about Quality of Service (QoS) in particularly IPv4 (Internet Protocol version 4). The inevitable exhaustion of the remaining IPv4 address pool has become progressively evident. As the evolution of Internet Protocol (IP) continues, the deployment of IPv6 QoS is underway. Today, there is limited experience in the deployment of QoS for IPv6 traffic in MPLS backbone networks in conjunction with DiffServ (Differentiated Services) support. DiffServ itself does not have the ability to control the traffic which has been taken for end-to-end path while a number of links of the path are congested. In contrast, MPLS Traffic Engineering (TE) is accomplished to control the traffic and can set up end-to-end routing path before data has been forwarded. From the evolution of IPv4 QoS solutions, we know that the integration of DiffServ and MPLS TE satisfies the guaranteed QoS requirement for real-time applications. This thesis presents a QoS performance study of real-time applications such as voice and video conferencing over DiffServ with or without MPLS TE in IPv4/IPv6 networks using Optimized Network Engineering Tool (OPNET). This thesis also studies the interaction of Expedited Forwarding (EF), Assured Forwarding (AF) traffic aggregation, link congestion, as well as the effect of various performance metrics such as packet end-to-end delay, packet delay variation, queuing delay, throughput and packet loss. The effectiveness of DiffServ and MPLS TE integration in IPv4/IPv6 network is illustrated and analyzed. The thesis shows that IPv6 experiences more delay and loss performance than their IPv4 counterparts.

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