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  • 1.
    Ahlgren, Anna
    Linköping University, Department of Computer and Information Science.
    MobiAnn: androidapplikationen som underlättar lärares arbetsuppgifter2011Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    Examensarbetet diskuterar behovet av ett stödsystem för lärare vid undervisning och tar upp olika aspekter utifrån lärarnas arbetssituation. Som en del av denna diskussion finns en implementation av ett system i form av en Androidapplikation.

    Applikationen ger lärarna möjlighet till ett stödsystem med olika användningsområde som närvarokontroll, anmärkningsmöjligheter om förseningar och stök under lektionstid, verktyg för att anteckna elevarbete och motivera betyg direkt på plats.

    Stor vikt har lagts på att göra applikationen lättanvänd och användarvänlig och därför har tester med användare varit en stor del under utvecklingen.

  • 2.
    Alesand, Alexander
    Linköping University, Department of Computer and Information Science, Software and Systems.
    Emulating 3G Network Characteristics on WiFi Networks2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Mobile applications should work regardless of which type of wireless interface is used, and should be able to conceal unstable connections from the user to improve user experience. Therefore, network testing is important when developing mobile applications, but it is a challenge to reproduce network conditions when using real cellular networks since the test engineer has no control over the quality of the cellular network. Existing software tools can restrict bandwidth and add latency to the connection, but these tools do not accurately emulate cellular networks.

    This thesis proposes a system where it is possible to shape the network traffic for connected devices to mimic the network patterns of a real cellular connection when running on a WiFi connection. The design presented in this thesis is intended for testing mobile applications under diverse 3G connection parameters, such as latency, bandwidth and other characteristics.

    This thesis was conducted at Spotify, a company that provides a music streaming service which is a frequent user of network data traffic. The 3G emulator was evaluated using the Spotify Android application by measuring the correlation between packet traces from a real 3G connection and the 3G emulator. This correlation was compared to the correlation between packet traces from a real 3G connection and the current network emulator at Spotify. The evaluation shows that the proposed 3G emulator outperforms the current network emulator when performing tests on the Spotify application for Android. By using this emulator, we expect the network testing to become more effective as any 3G condition can be tested with repeatable results.

  • 3.
    Ali, Asif
    et al.
    Linköping University, Department of Computer and Information Science.
    Ramzan, Faheem
    Linköping University, Department of Computer and Information Science.
    Analysis and Monitoring of Team Collaboration in Emergency Response Training supported by a Web Based Information Management System2009Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Our objective in this thesis work is to analyze and manage the log files which are generated after a number of experiments series on different groups using C3Fire simulation environment. It includes analyzing and extracting information from log files, and then maintaining this information in a database. This should be presented with a web interface through ICEfaces Ajax framework for Java. Log Files are generated after a number of experiments series on the different groups. All sequences and information related to task performed by team in group is organized in session log files. The work is divided into different steps; first step is to analyze and extract data from log files, and properly arrange it in several different tables in a database, for this MySQL database is used to store the information. The web interface of log file management system is implemented using ICEfaces Ajax framework, and is based on the statistics of log files generated from the C3Fire environment.  User would be able to add/remove the log files, also can view or edit the details of each session log file in database through web interface. Different events can be generated, and logged for the session information.

    C3Fire is an environment that supports training and research in team collaboration. The environment is mainly used in command, control and communication research, and in training of team decision making. Many humanitarian relief operations are doing their work without having any practice. When some disaster events occur, they cannot perform their jobs effectively. Effective and efficient relief operation is the need of humanity; even that’s not enough to move teams to the disaster place at right time; communication and co-ordination among the team members is the big factor to make effective and well-organized work. C3Fire is a simulation system which provides the training for team members to handle such type of disaster events, and makes the work more proficient at that time by doing effective coordination.

  • 4.
    Andersson, Ulf
    Linköping University, Department of Electrical Engineering. Linköping University, The Institute of Technology.
    Betalkort: Slutrapport1980Report (Other academic)
    Abstract [sv]

    Idén till Universalkort uppkom för cirka tre år sedan, som en följd av ett examensarbete med namnet "ID- kort med minne". Där undersöktes möjligheten att placera ett nonvolatilt minne på ett kort. Fortsättningen på det projektet beskrivs kort under rubriken ”Existerande hårdvarusystem”.

    Utvecklingen av Betal- och Universalkortsidén har sedan dess bedrivits i samarbete med personal på Institutionen för Systemteknik inom ämnesområdet informationsteori vid LiTH. Jag vill rikta ett varmt tack till dessa och speciellt till Rolf Blom , Robert Forchheimer och Ingemar Ingemarsson för deras bidrag till arbetet.

  • 5.
    Andréasson, Dan
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Morja, Daniel
    Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Science & Engineering.
    Rekonstruktion och optimering av laddningstid för en webbsida i Ruby on Rails2015Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    Många verksamheter representeras idag på internet i omodern stil vilket kan påverka besökarens uppfattning om verksamheten negativt. I detta arbete har en webbsida rekonstruerats. Webbsidan tillhör en förening med verksamhet inom gaming och esport. Rekonstruktionen är till för att ge besökare en klar bild av vad föreningens huvudverksamhet är och för att integrera streamingtjänsten Twitch för att ge besökare ytterligare en anledning att återbesöka sidan. Dessutom har laddningstiden för startsidan optimerats för att ge bättre besökupplevelse. Med hjälp av Redis och metoden Eager loading visar arbetet hur man kan sänka laddningstiden på en webbsida.

  • 6.
    Arman, Sheikh Ali
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    RESTful Mobile Application for Android: Mobile Version of Inspectera Online2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Web service-based mobile applications have become emergent in the recent years. Representational State Transfer (REST) architecture style introduced the concept of Resource Oriented Architecture (ROA), which has been widely used for building applications for all platforms. This master’s thesis designs and develops a Web service-based mobile application for Android platform following the constraints of REST architectural style. It also proposes an authentication model for RESTful applications. The master’s thesis is completed at the company Inspectera HK AB in Norrköping, Sweden. The developed application is called the “Mobile version of Inspectera Online.” 

  • 7.
    Arvidsson, Carl
    et al.
    Linköping University, Department of Computer and Information Science.
    Bergström, David
    Linköping University, Department of Computer and Information Science.
    Eilert, Pernilla
    Linköping University, Department of Computer and Information Science.
    Gudmundsson, Håkan
    Linköping University, Department of Computer and Information Science.
    Henriksson, Christoffer
    Linköping University, Department of Computer and Information Science.
    Magnusson, Filip
    Linköping University, Department of Computer and Information Science.
    Nåbo, Henning
    Linköping University, Department of Computer and Information Science.
    Petersén, Elin
    Linköping University, Department of Computer and Information Science.
    Utveckling av en applikation för framtagning av hjärnresponser vid funktionell magnetresonanstomografi2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Rapporten behandlar utvecklandet av programvaran JABE som ska användas i forskning om hjärnresponser. Syftet med rapporten är att utreda frågeställningarna kring hur ett sådant system kan utformas så att det skapar värde för kund och samtidigt underlättar vidareutveckling. Rapporten behandlar även hur ett användargränssnitt kan anpassas för en användares kunskapsnivå och vilka erfarenheter som kan dokumenteras från projektet i allmänhet. Problemet tacklas med stark kundkontakt, flera enkätundersökningar, agila arbetsmetodiker och genomgående dokumentering. Programvaran JABE är beställd av CMIV, centrum för medicisk bildvetenskap och visualisering, vid Linköpings Universitet och är den enda i sitt slag. Resultatet är, förutom en programvara, en genomgående beskrivning av erfarenheter, beskrivning av systemet och en utvärdering av SEMAT Kernel ALPHA. Kandidatrapporten innehåller även åtta individuella bidrag som gör fördjupningar i områden kopplade till projektet.

  • 8.
    Axelsson, Jesper
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, The Institute of Technology.
    Implementering av PostgreSQL som databashanterare för MONITOR2014Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    Monitors affärssystem MONITOR är under ständig utveckling och i och med detta ville man kolla upp huruvida PostgreSQL skulle kunna användas som DBMS istället för det nuvarande; Sybase SQL Anywhere. Examensarbete har därför bestått av en jämförelse hur PostgreSQL står sig jämte andra DBMS:er, en implementering utav en PostgreSQLdatabas som MONITOR arbetar mot samt ett prestandatest utav skapandet av databasen.

    I många avseenden verkar PostgreSQL vara ett alternativ till SQL Anywhere;

    1. Alla datatyper finns i båda dialekterna.
    2. Backup av data finns i olika utföranden och går att automatisera
    3. Enkelt att installera och uppdatera.
    4. Ingen licensieringskostnad existerar.
    5. Support finns tillgänglig i olika former.

    Dock så är inte PostgreSQL ett bra DBMS att byta till i dagsläget då systemet inte fungerade på grund av att vissa uttryck inte översattes ordentligt samt att ingen motsvarighet till LIST existerar. Ännu större är dock problemet med tiden det tar att flytta data till en PostgreSQL-databas då det inte är intressant att lösa problem med funktioner i systemet om det ändå inte går att använda på grund utav att konvertering av data tar så lång tid som det gör.

  • 9.
    Ayaz, Muhammad
    Linköping University, Department of Computer and Information Science.
    Model-Based Diagnosis of Software Functional Dependencies2010Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Researchers have developed framework for diagnosis analysis that are called “Model Based Diagnosis Systems”. These systems are very general in scope, covers a wide range of malfunctions uncovering and identifying repair measures. This thesis is an effort to diagnose complex and lengthy static source code. Without executing source code discrepancies can only be identified by finding procedural dependencies.

    With respect to modern programming languages, many software bugs arise due to logical erroneous calculations or miss handling of data structures. Modern Integrated Development Environments (IDE) like Visual Studio, J-Builder and Eclipse etc are strong enough to analyze and parse static text code to identify syntactical and type conversion errors. Some of IDE’s can automatically fix such kind of errors or provide different possible suggestions to developer.

    In this thesis we have analyzed and extracted functional dependencies of source code. This extracted information can increase programmer’s understanding about code when they are extremely large or complex. By modeling this information into a model system, reduces time to debug the code in case of any failure. This increases productivity in terms of software development and in debugger skills as well. The main contribution of this thesis is the use of model based diagnosis techniques on software functional dependency graphs and charts.

    Keywords: Model Based Diagnosis Systems, Integrated Development Environments, Procedural Dependencies, Erroneous calculations, Call graphs, Directed graph markup language.

  • 10.
    Baloch, Adeel
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Graphical Web Interface for OpenModelica Platform2013Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    “OPENMODELICA is an open-source Modelica-based modeling and simulation environment intended for industrial and academic usage. Its long-term development is supported by a non-profit organization – the Open Source Modelica Consortium (OSMC).”

    OpenModelica aims to provide an enhanced, Open Source Modelica modeling and simulation environment and this thesis is an addition in this direction. 

    The purpose of this thesis is to create a web based graphical connection editor. There are other open-source connection editors available, but these editors were desktop applications. There is one web based editor but it is a textual editor. Desktop applications need installation and space on the local system. OMWeb connection editor is the first web based graphical connection editor that runs on a web browser. It’s a web platform for OpenModelica and provides the environment for modeling and simulation in the Modelica Modeling Language.

    The OMWeb connection editor can run on any system without the need for an OpenModelica installation. If a system is connected to the internet, and contains a web browser, it can run the OMWeb connection editor. The OMWeb connection editor uses Java Runtime Environment to run an applet in the browser. The user can create models graphically; but they can also be viewed in the textual format. The user can simulate and plot his models. The plot file generated for the model can be downloaded from the server. 

    The OMWeb Connection Editor uses Servlet to handle requests from the client. The servlet is responsible for the communication with OpenModelica Compiler. It also gets the results from OMC and sends them back to the client. In our case the browser is the client.

  • 11.
    Barrdahl, Adam
    et al.
    Linköping University, Department of Computer and Information Science.
    Berg, Josefin
    Linköping University, Department of Computer and Information Science.
    Fridberg, Pontus
    Linköping University, Department of Computer and Information Science.
    Gunnarsson, David
    Linköping University, Department of Computer and Information Science.
    Lidberg, Sara
    Linköping University, Department of Computer and Information Science.
    Lindblom, Martin
    Linköping University, Department of Computer and Information Science.
    Melin Wenström, Peter
    Linköping University, Department of Computer and Information Science.
    Olsson, Gustav
    Linköping University, Department of Computer and Information Science.
    Ström, Johan
    Linköping University, Department of Computer and Information Science.
    Implementering av en användbar e-butik för tygmärken: En praktisk fallstudie av webbapplikationen Festing2016Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    This report covers the development of the web application Festing and the results and experiences which have been reached and learned during the process. The purpose of the study was to examine how the selling of patches could be both simplified and improved by using an advanced web application designed with focus on usability. Currently the patches are sold in a large but geographically and temporally limited market at Linköping University. The project was comprised of a case study and development of an application following the agile project framework Scrum. According to this the projects has been split up into four sprints after each of which a working product was delivered. This resulted in a usable web application with an intuitive design and multiple functions linked to the selling and buying of patches. Based on interviews, surveys and usability tests this web application is considered to have the long-term potential to take over the current physical market of textile patches.

  • 12.
    Bendtsen, Marcus
    Linköping University, Department of Computer and Information Science.
    Androidutveckling med slutanvändarens idéer som fokus2011Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    Under slutet av 2010 och våren 2011 har ett utvecklingsprojekt pågått hos AlexIT AB. Målet var att skapa en mobilapplikatioin för individer som vill bokföra sin alkoholkonsumtion. Som en del utav arbetet önskade projektgruppen bjuda in slutanvändare till processe, för att ta del utav deras idéer och feedback.

    Genom att låta en grupp slutanvändare själva skissa och beskriva sina lösningar och en annan grupp jobba fram en pappersprototyp tillsammans i en workshop gavs utvecklaren ett brett stöd för val i designprocessen.

    Det visar sig att de som individuellt skissa har inte låtit sig begränsas av antingen kravspeciifikationen eller mediet (mobiltelefon), utan har istället beskrivit funktionalitet framför design. Tvärtom har de som jobbat i workshop hållit sig inom ramarna för kravspecifikationen och mediet och skapat en komplett och implementerbar pappersprototyp.

  • 13.
    Berglund, Aseel
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    Heintz, Fredrik
    Linköping University, Department of Computer and Information Science, Artificial Intelligence and Intergrated Computer systems. Linköping University, The Institute of Technology.
    Integrating Soft Skills into Engineering Education for Increased Student Throughput and more Professional Engineers2014In: Proceedings of LTHs 8:e Pedagogiska Inspirationskonferens (PIK), Lund, Sweden: Lunds university , 2014Conference paper (Other academic)
    Abstract [en]

    Soft skills are recognized as crucial for engineers as technical work is becoming more and more collaborative and interdisciplinary. Today many engineering educations fail to give appropriate training in soft skills. Linköping University has therefore developed a completely new course “Professionalism for Engineers” for two of its 5-year engineering programs in the area of computer science. The course stretches over the first 3 years with students from the three years taking it together. The purpose of the course is to give engineering students training in soft skills that are of importance during the engineering education as well as during their professional career. The examination is based on the Dialogue Seminar Method developed for learning from experience and through reflection. The organization of the course is innovative in many ways.

  • 14.
    Bergman, Sara
    Linköping University, Department of Computer and Information Science, Software and Systems.
    Permissioned Blockchains and Distributed Databases: A Performance Study2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Blockchain technology is a booming new field in both computer science and economicsand other use cases than cryptocurrencies are on the rise. Permissioned blockchains are oneinstance of the blockchain technique. In a permissioned blockchain the nodes which validatesnew transactions are trusted. Permissioned blockchains and distributed databasesare essentially two different ways for storing data, but how do they compare in terms ofperformance? This thesis compares Hyperledger Fabric to Apache Cassandra in four experimentsto investigate their insert and read latency. The experiments are executed usingDocker on an Azure virtual machine and the studied systems consist of up to 20 logicalnodes. Latency measurements are performed using varying network size and load. Forsmall networks, the insert latency of Cassandra is twice as high as that of Fabric, whereasfor larger networks Fabric has almost twice as high insert latencies as Cassandra. Fabrichas around 40 ms latency for reading data and Cassandra between 150 ms to 250 ms, thusit scales better for reading. The insert latency of different workloads is heavily affected bythe configuration of Fabric and by the Docker overhead for Cassandra. The read latency isnot affected by different workloads for either system.

  • 15.
    Berndtsson, Wilhelm
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Claesson, Filip
    Linköping University, Department of Computer and Information Science.
    Daveby, Eric
    Linköping University, Department of Computer and Information Science.
    Gudjonsson, Adam
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Lemos, Josefine
    Linköping University, Department of Computer and Information Science.
    Rosander, Sebastian
    Linköping University, Department of Computer and Information Science.
    Åquist, Alexander
    Linköping University, Department of Computer and Information Science.
    Webbutveckling och agila arbetsmetoder: erfarenheter från projekt inom programvaruutveckling2014Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [sv]

    Rapporten beskriver framtagandet av en webbshop för glasögonförsäljning. Läsaren får ta del av lärdomar om hur det fungerar att arbeta efter den agila projektmodellen Scrum i praktiken och förslag till hur metodiken kan anpassas för effektiv användning i ett utvecklingsteam. Vidare diskuteras även hur sammanslagning av flera projektmodeller kan ske för att skapa en mer produktiv projektmiljö. 

    Lösningar till tekniska problem som uppstått under projektets gång presenteras och diskuteras utifrån ett utvecklarprespektiv. Vidare presenteras en marknadsundersökning där kundsegmentet identifieras och analyseras för utformning av slutprodukten. Utmärkande för slutprodukten är en smidig och enkel köpprocess uppdelad i tre enkla steg. 

  • 16.
    Berntzon, Fredrik
    et al.
    Linköping University, Department of Computer and Information Science.
    Dahlström, Didrik
    Linköping University, Department of Computer and Information Science.
    Fries, Niklas
    Linköping University, Department of Computer and Information Science.
    Håstad, Oskar
    Linköping University, Department of Computer and Information Science.
    Markgren, Hedvig
    Linköping University, Department of Computer and Information Science.
    Persson, Gustaf
    Linköping University, Department of Computer and Information Science.
    Strandberg, Axel
    Linköping University, Department of Computer and Information Science.
    Söderlind, Marcus
    Linköping University, Department of Computer and Information Science.
    Implementering av en användbar och förtroendeingivande C2C-plattform för matlådor: En fallstudie av webbapplikationen Delish2017Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    This report covers a case study performed at Linköping University. The project consists of the development of a web application of type e-commerce, named Delish, which is a service for trading lunch boxes among students. The report treats the compilation of a theoretical framework, the development and its results followed by a discussion. The web application serves as a foundation in order to examine how an application should be designed to ensure high navigability and simplicity while establishing user trust. Information is gathered in order to define a theoretical and methodical framework. The development is accompanied by an evaluation of the products fulfilment of earlier set goals, by conducting market surveys and usability testing. Navigability is achieved through the implementation of different navigational systems and the application is perceived as simple as a result of effective use of colours and typography. Through the implementation of a ranking system and communication of data integrity, the application is perceived as trustworthy.

  • 17.
    Birksjö, Marcus
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Häggmyr, Daniel
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Lindqvist, David
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Nowén, Viktoria
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Petré, Fredrik
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Sanner, Alexander
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Sundblad, Anton
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Torrusio, Cristian
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Applikationsutveckling: med parprogrammering och kundinteraktion i blickfånget2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This candidate report describes how a group of students can develop a smartphone applicationwithout any prior knowledge in the field. To make the project more realistic there is also a clientwho has requests and wishes regarding the finished product.The document describes the methods used to produce the application and also includesexperiences that the group gained. How the interaction with the client has been performed togain a good understanding of what they wished the product to become is also accounted for.The research questions focus on how the development has proceeded and how one can learnsomething new in a relatively short timespan as a group.

  • 18.
    Bladin, Kalle
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Broberg, Erik
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Design and Implementation of an Out-of-Core Globe Rendering System Using Multiple Map Services2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis focuses on the design and implementation of a software system enabling out-of-core rendering of multiple map datasets mapped on virtual globes around our solar system. Challenges such as precision, accuracy, curvature and massive datasets were considered. The result is a globe visualization software using a chunked level of detail approach for rendering. The software can render texture layers of various sorts to aid in scientific visualization on top of height mapped geometry, yielding accurate visualizations rendered at interactive frame rates. The project was conducted at the American Museum of Natural History (AMNH), New York and serves the goal of implementing a planetary visualization software to aid in public presentations and bringing space science to the public. The work is part of the development of the software OpenSpace, which is the result of a collaboration between Linköping University, AMNH and the National Aeronautics and Space Administration (NASA) among others.

  • 19.
    Bohlin, Johan
    Linköping University, Department of Computer and Information Science.
    Visualisering av elektroniska kopplingsscheman2009Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    AnSyn AB är ett företag i Linköping som utvecklar programvara för att optimera analog elektronik. I deras program Analog Dimensions finns en visualiseringsmodul som ritar upp de kopplingsscheman som elektronikkonstruktören arbetar med. Ansyn var inte nöjda med den lösningen de hade. Den gamla visualiseringsmodulen hade flera begränsningar och i denna rapport kan du följa arbetet med att ta fram en ny visualiseringsmodul. Arbetet resulterade i en helt ny visualiseringsmodul som saknar de begränsningar som den gamla visualiseringsmodulen hade. Visualiseringsmodulen är helt skriven i Java och använder sig av ett grafikbibliotek vid namn Netbeans Visual Library. Det är ett bibliotek med öppen källkod som bland annat kan användas för visualisering av vektorgrafik. Rapporten innehåller även en undersökning av programbibliotek för Java som hanterar vektorgrafik. I undersökningen studerades totalt 15 olika bibliotek.

  • 20.
    Borg, Andreas
    et al.
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    Patel, Mikael
    Ericsson AB, Linköping, Sweden.
    Sandahl, Kristian
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    Extending the OpenUP/Basic Requirements Discipline to Specify Capacity Requirements2007In: Requirements Engineering Conference, 2007. RE '07, IEEE Computer Society, 2007, p. 328-333Conference paper (Refereed)
    Abstract [en]

    Software processes, such as RUP and agile methods, focus their requirements engineering part on use cases and thus functional requirements. Complex products, such as radio network control software, need special handling of non-functional requirements as well. We describe how we used the eclipse process framework to augment the open and minimal OpenUP/basic process with improvements found in management of capacity requirements in a case-study at Ericsson. The result is compared with another project improving RUP to handle performance requirements. The major differences between the improvements are that 1) they suggest a special, dedicated performance manager role and we suggest that present roles are augmented, 2) they suggest a bottom-up approach to performance verification while we focus on system performance first, i.e. top-down. Further, we suggest augmenting UMLl-2 models with capacity attributes to improve information flow from requirements to implementation.

  • 21.
    Borg, Andreas
    et al.
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    Patel, Mikael
    Ericsson AB, Linköping, Sweden.
    Sandahl, Kristian
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    Good Practice and Improvement Model of Handling Capacity Requirements of Large Telecommunication Systems2006In: 14th IEEE International Requirements Engineering Conference (RE'06), Minneapolis/S:t Paul, Los Alamitos, CA: IEEE Computer Society , 2006, p. 245-250Conference paper (Refereed)
    Abstract [en]

    There is evidence to suggest that the software industry has not yet matured as regards management of nonfunctional requirements (NFRs). Consequently the cost of achieving required quality is unnecessarily high. To try and avoid this, the telecommunication systems provider Ericsson defined a research task to try and improve the management of requirements for capacity, which is one of the most critical NFRs. Linkoping University joined in the effort and conducted an interview series to investigate good practice within different parts of the company. Inspired by the interviews and an ongoing process improvement project a model for improvement was created and activities were synthesized. This paper contributes the results from the interview series, and details the subprocesses of specification that should be improved. Such improvements are about understanding the relationship between numerical entities at all system levels, augmenting UML specifications to make NFRs visible, working with time budgets, and testing the sub system level components on the same level as they are specified.

  • 22.
    Borg, Andreas
    et al.
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    Patel, Mikael
    Ericsson AB, Linköping, Sweden.
    Sandahl, Kristian
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    Integrating an Improvement Model of Handling Capacity Requirements with OpenUP/Basic Process2007In: 13th International working conference on Requirements Engineering: Foundations for Software Quality (REFSQ'07), Trondheim, Norway, Berlin Heidelberg: Springer , 2007, p. 341-354Conference paper (Refereed)
    Abstract [en]

    Contemporary software processes and modeling languages have a strong focus on Functional Requirements (FRs), whereas information of Non-Functional Requirements (NFRs) are managed with text-based documentation and individual skills of the personnel. In order to get a better understanding of how capacity requirements are handled, we carried out an interview series with various branches of Ericsson. The analysis of this material revealed 18 Capacity Sub-Processes (CSPs) that need to be attended to create a capacity-oriented development. In this paper we describe all these sub-processes and their mapping into an extension of the OpenUP/Basic software process. Such an extension will support a process engineer in realizing the sub-processes, and has at the same time shown that there are no internal inconsistencies of the CSPs. The extension provides a context for continued research in using UML to support negotiation between requirements and existing design.

  • 23.
    Borg, Andreas
    et al.
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    Patel, Mikael
    Ericsson AB, Linköping, Sweden.
    Sandahl, Kristian
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    A Method for Improving the Treatment of Capacity Requirements in Large Telecommunication SystemsManuscript (Other academic)
    Abstract [en]

    Non-functional requirements crosscut functional models and are more difficult to enforce in system models. This paper describes a long-term research collaboration regarding capacity requirements between Linköping University and Ericsson AB. We describe an industrial case study on non-functional requirements as a background. Succeeding efforts dedicated to capacity include a detailed description of the term, a best practice inventory within Ericsson, and a pragmatic approach for how to annotate UML models with capacity information. The results are also represented as a method plug-in to the OpenUP software process and an anatomy facilitating the possibility to assess and improve an organization’s abilities to develop for capacity. The results combine into a method for how to improve the treatment of capacity requirements in large-scale software systems. Both product and process views are included, with emphasis on the latter.

  • 24.
    Borg, Andreas
    et al.
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    Yong, Angela
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    Carlshamre, Pär
    Linköping University, Department of Computer and Information Science, MDA - Human Computer Interfaces. Linköping University, The Institute of Technology.
    Sandahl, Kristian
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    The Bad Conscience of Requirements Engineering: An Investigation in Real-World Treatment of Non-Functional Requirements2003In: Third Conference on Software Engineering Research and Practice in Sweden (SERPS'03), Lund, 2003, p. 1-8Conference paper (Refereed)
    Abstract [en]

    Even though non-functional requirements (NFRs) are critical in order to provide software of good quality, the literature of NFRs is relatively sparse. We describe how NFRs are treated in two development organizations, an Ericsson application center and the IT department of the Swedish Meteorological and Hydrological Institute. We have interviewed professionals about problems they face and their ideas on how to improve the situation. Both organizations are aware of NFRs and related problems but their main focus is on functional requirements,primarily because existing methods focus on these. The most tangible problems experienced are that many NFRs remain undiscovered and that NFRs are stated in non-measurable terms. It became clear that the size andstructure of the organization require proper distribution of employees’ interest, authority and competence of NFRs. We argue that a feasible solution might be to strengthen the position of architectural requirements, which are more likely to emphasize NFRs.

  • 25.
    Branting, Jonatan
    et al.
    Linköping University, Department of Computer and Information Science.
    Byhlin, Martin
    Linköping University, Department of Computer and Information Science.
    Erhard Olsson, Niklas
    Linköping University, Department of Computer and Information Science.
    Fundin Bengtsson, August
    Linköping University, Department of Computer and Information Science.
    Johns, Rasmus
    Linköping University, Department of Computer and Information Science.
    Lundberg, Martin
    Linköping University, Department of Computer and Information Science.
    Müller, Hanna
    Linköping University, Department of Computer and Information Science.
    Nyberg, Adam
    Linköping University, Department of Computer and Information Science.
    Pettersson, Niklas
    Linköping University, Department of Computer and Information Science.
    Simuleringsmiljö för mobila nätverk2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport innefattar det arbete som nio studenter från kursen TDDD96: Kandidatprojekt i programvaruutveckling vid Linköpings universitet ägnat sig åt under vårterminen 2016. Projektet genomfördes med målsättningen att utveckla ett grafiskt användargränssnitt som skulle visualisera simuleringar av teledatatrafik i 2G-miljöer. Arbetet har varit en lärande process som omfattat gruppdynamik, nya tekniska utmaningar och ett undersökande av hur utvecklingen i ett projekt går från en beställning till en önskvärd leverans. Gruppen har arbetat i korta intervaller med täta möten och prioriteringslistor med aktiviteter. Resultatet hittills är en prototyp med interaktiv simulering via uppkoppling mot kundens servrar som bådar gott för fortsatt utveckling.

  • 26.
    Broman, David
    et al.
    Linköping University, Department of Computer and Information Science.
    Fritzson, Peter
    Linköping University, Department of Computer and Information Science.
    High-Order Acausal Models2009In: Simulation news europe, ISSN 0929-2268, Vol. 19, no 1Article in journal (Refereed)
  • 27.
    Byers, David
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, The Institute of Technology.
    Improving Software Security by Preventing Known Vulnerabilities2013Doctoral thesis, monograph (Other academic)
    Abstract [en]

    From originally being of little concern, security has become a crucial quality factor in modern software. The risk associated with software insecurity has increased dramatically with increased reliance on software and a growing number of threat agents. Nevertheless, developers still struggle with security. It is often an afterthought, bolted on late in development or even during deployment. Consequently the same kinds of vulnerabilities appear over and over again.

    Building security in to software from its inception and constantly adapting processes and technology to changing threats and understanding of security can significantly contribute to establishing and sustaining a high level of security.

    This thesis presents the sustainable software security process, the S3P, an approach to software process improvement for software security that focuses on preventing known vulnerabilities by addressing their underlying causes, and sustaining a high level of security by adapting the process to new vulnerabilities as they become known. The S3P is designed to overcome many of the known obstacles to software process improvement. In particular, it ensures that existing knowledge can be used to its full potential and that the process can be adapted to nearly any environment and used in conjunction with other other software security processes and security assurance models.

    The S3P is a three-step process based on semi-formal modeling of vulnerabilities, ideally supported by collaborative tools. Such proof-of-concept tools were developed for all parts of the process as part of the SHIELDS project.

    The first two steps of the S3P consist in determining the potential causes of known vulberabilities at all stages of software development, then identifying measures that would prevent each individual cause. These steps are performed using visual modeling languages with well-defined semantics and a modeling workflow. With tool support, modeling effort can be progressively reduced through collaboration and use of pre-existing models.

    Next, the costs of all potential measures are estimated using any suitable method. This thesis uses pairwise comparisons in order to support qualitative judgements. The models and costs yield a boolan optimization problem that is solved using a search-based heuristic, to identify the best set of measures to prevent selected vulnerabilities.

    Empirical evaluation of the various steps of the process has verified a number of key aspects: the modeling process is easy to learn and apply, and the method is perceived by developers as providing value and improving security. Early evaluation results were also used to refine certain aspects of the S3P.

    The modeling languages that were introduced in the S3P have since been enhanced to support other applications. This thesis presents security goal models (SGMs), a language that subsumes several security-related modeling languages to unify modeling of threats, attacks, vulnerabilities, activities, and security goals. SGMs have formal semantics and are sufficiently expressive to  support applications as diverse as automatic run-time testing, static analysis, and code inspection. Proofof-concept implementations of these applications were developed as part of the SHIELDS project.

    Finally, the thesis discusses how individual components of the S3P can be used in situations where the full process is inappropriate.

  • 28.
    Byers, David
    et al.
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, The Institute of Technology.
    Shahmehri, Nahid
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, The Institute of Technology.
    Graphical Modeling of Security Goals and Software Vulnerabilities2015In: Handbook of Research on Innovations in Systems and Software Engineering / [ed] Vicente García Díaz, Juan Manuel Cueva Lovelle, B. Cristina Pelayo García-Bustelo, IGI Global, 2015, p. 1-31Chapter in book (Refereed)
    Abstract [en]

    Security has become recognized as a critical aspect of software development, leading to the development of various security-enhancing techniques, many of which use some kind of custom modeling language. Models in different languages cannot readily be related to each other, which is an obstacle to using several techniques together. The sheer number of languages is, in itself, also an obstacle to adoption by developers. The authors have developed a modeling language that can be used in place of four existing modeling languages: attack trees, vulnerability cause graphs, security activity graphs, and security goal indicator trees. Models in the new language can be transformed to and from the earlier language, and a precise definition of model semantics enables an even wider range of applications, such as testing and static analysis. This chapter explores this new language.

  • 29.
    Byers, David
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Computer and Information Science, Database and information techniques.
    Shahmehri, Nahid
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, The Institute of Technology.
    Modeling Security Goals and Software Vulnerabilities2011In: Dependability and Computer Engineering: Concepts for Software-Intensive Systems / [ed] Luigia Petre, Kaisa Sere, Elena Troubitsyna, IGI Global, 2011, p. 171-198Chapter in book (Other academic)
    Abstract [en]

    Security is becoming recognized as an important aspect of software development, leading to the development of various security-enhancing techniques, many of which use some kind of custom modeling language. Models in different languages cannot readily be related to each other, which is an obstacle to using several techniques together. The sheer number of languages is, in itself, also an obstacle to adoption by developers.

    We have developed a modeling language that can be used in place of four existing modeling languages: attack trees, vulnerability cause graphs, security activity graphs, and security goal indicator trees. Our language is more precise than earlier languages, which allows models to be used in automated applications such as testing and static analysis. Models in the new language can be transformed to and from earlier languages. We also present a data model that allows users to relate different kinds of models and model elements to each other and to core security knowledge.

  • 30.
    Byers, David
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Computer and Information Science, Database and information techniques.
    Shahmehri, Nahid
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, The Institute of Technology.
    Unified modeling of attacks, vulnerabilities and security activities2010In: Proceedings of the 2010 ICSE Workshop on Software Engineering for Secure Systems, New York, USA: ACM , 2010, p. 36-42Conference paper (Refereed)
    Abstract [en]

    Security is becoming recognized as an important aspect of software development, leading to the development of many different security-enhancing techniques, many of which use some kind of custom modeling language. Models in these different languages cannot readily be related to each other, which is an obstacle to using several techniques together. The sheer number of languages is, in itself, also an obstacle to adoption by developers.

    In this paper we present a modeling language that can be used in place of four existing modeling languages: attacktrees, vulnerability cause graphs, security activity graphs, and security goal indicator trees. Models in our language can be more precise than earlier models, which allows them to be used in automated applications, such as automatic testing and static analysis. Models in the new language can be derived automatically from models in the existing languages, and can be viewed using existing notation.

    Our modeling language exploits a data model, also presented in this paper, that permits rich interconnections between various items of security knowledge. In this data model it is straightforward to relate different kinds of models, and thereby different software security techniques, to each other.

  • 31.
    Böhlin, Per
    Linköping University, Department of Computer and Information Science.
    On Patterns for Refactoring Legacy C++ Code into a Testable State Using Inversion of Control2010Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Amending old projects of legacy code to include agile practices such as extensive unit testing and refactoring has proven difficult. Since automated unit testing was not widely used a decade ago, much code has been written without unit testing in mind. This is especially true for C++ where RAII has been the dominant pattern .This has resulted in a lot of code that suffers from what best can be described as low testability. This also strongly impedes the creation of new unit tests to already existing code. Due to the lack of unit tests, refactoring is done sparsely and with great reluctance.

    This thesis work tries to remedy that and, in the scope of a limited case study on an existing code base, looks into different ways of creating and utilizing object seams in legacy C++ code to decouple dependencies to make isolated testing possible. This regards to:

    • What are the impediments for code to be testable in an isolated setting?
    • What are the steps for refactoring code to a testable state?

    The results can be summarized as to contain a list of factors affecting testability, among them: the use of asserts, global state, object instantiation, work in constructor and breaking Law of Demeter. Further with regards to patterns for refactoring code to a testable state, two types of patterns have crystallized: the injection of dependencies and the masking of dependencies using various techniques. The effect these two base patterns have on breaking dependencies on the base level and the Meta level is outlined. A catalogue of patterns has been compiled as part of the appendix.

     

    Inversion of Control (IoC) is a principle used to decoupling classes and since strong dependences is often an attribute giving grievances with regard to testability, it was a central concern in this thesis. IoC can be simplified from a developer standpoint with the help of frameworks or what is usually referred to as IoC containers. Two IoC containers for C++ were evaluated:

    • Autumn Framework
    • PocoCapsule

    In the evaluation of the two IoC containers it was concluded that Autumn was not mature enough as of the time of the evaluation to be used in production setting. PocoCapsule, even though compelling for some of its powerful features with regard to DSM and HOT, its configuration sometimes require in-code workarounds, affecting its usability in some set of scenarios.

    However, the big difference was with regard to how the two containers approaches configuration. PocoCapsule uses static analysis of its XML configuration file making it truly declarative while Autumn does runtime parsing and dynamic invocations resulting in a situation closer to procedural scripting.

  • 32.
    Cerny, David
    et al.
    Linköping University, Department of Computer and Information Science.
    Andersson, Erik
    Linköping University, Department of Computer and Information Science.
    Arve, Fredrik
    Linköping University, Department of Computer and Information Science.
    Falk, Linus
    Linköping University, Department of Computer and Information Science.
    Hergart, Johan
    Linköping University, Department of Computer and Information Science.
    Lidquist, John Andrée
    Linköping University, Department of Computer and Information Science.
    Serebrink, Rikard
    Linköping University, Department of Computer and Information Science.
    Waldenbäck, Tim
    Linköping University, Department of Computer and Information Science.
    Utformning och implementering av en webbapplikation med god navigerbarhet2017Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    According to a study made at Linköping University, there are few options besides self-catered food and buying food at a restaurant. According to the same survey, a majority of the students seek further options in the market. A proposed solution, tested here, is to develop a platform for selling and buying homemade food through a web application. Development takes place in iterations where design and functionality are supported by scientific theory. Changes are based on qualitative opinions from user tests at the end of each iteration. The work is specifically aimed at creating a design with associated features that allow quick navigation to the desired transaction while the user experiences a good navigability. The balance between navigability and time aspects has been central to the report and influenced all aspects of the web application's design. The report shows that it is possible to develop a web application according to the above criteria and identify what is essential for the users.

  • 33.
    Chen, Kairang
    et al.
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    Alvandpour, Atila
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
    A pipelined SAR ADC with gain-stage based on capacitive charge pump2017In: Analog Integrated Circuits and Signal Processing, ISSN 0925-1030, E-ISSN 1573-1979, Vol. 90, no 1, p. 43-53Article in journal (Refereed)
    Abstract [en]

    This paper presents a 14-bit, tunable bandwidth two-stage pipelined successive approximation analog to digital converter which is suitable for low-power, cost-effective sensor readout circuits. To overcome the high DC gain requirement of operational transconductance amplifier in the gain-stage, the multi-stage capacitive charge pump (CCP) was utilized to achieve the gain-stage instead of using the switch capacitor integrator. The detailed design considerations are given in this work. Thereafter, the 14-bit ADC was designed and fabricated in a low-cost 0.35-µm CMOS process. The prototype ADC achieves a peak SNDR of 75.6 dB at a sampling rate of 20 kS/s and 76.1 dB at 200 kS/s while consuming 7.68 and 96 µW, respectively. The corresponding FoM are 166.7 and 166.3 dB. Since the bandwidth of CCP is tunable, the ADC maintains a SNDR >75 dB upto 260 kHz. The core area occupied by the ADC is 0.589 mm2.

  • 34.
    Cronstrand, Rasmus
    Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Science & Engineering.
    Effects of design and feedback in a motion-based game2015Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Movement-based games are becoming more frequent in everyday lives. With easier access to webcams built into laptops and web-based games, a game which utilises both concepts can become a good option for everyday gaming.This study evaluates a movement-based game written in JavaScript using phaser.io which uses a webcam for control and HTML5 technique for capture. The main questions in the study are what observations can be done and are there any problems when developing a game with webcam-based motion-detection in regards to factors like flow, feedback and positioning. This study tries to answer these questions by building upon an existing game and implementing new functions and feedback and then observing how these effect the game-play. The results of the study showed that it is important to consider good feedback and how to position oneself when playing such a game and that more testing should be done to gain further knowledge about these two. But also that many of the implementations done made the person achieve flow while playing. Further work should be beneficial also to make the game even better while keeping it easy to play.

  • 35.
    Daniel, Andersson
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Erik, Bertilsson
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    August, Ernstsson
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Simon, Mehari
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Alfred, Axelsson
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Viktor, Danielsson
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Anders, Gustafsson
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Hampus, Tjäder
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Lågviktigt mätsystem för obemannad luftburen radiometri2014Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    Syftet med detta examensarbete var att lära sig att genomföra ett programutvecklingsprojekt under realistiska förutsättningar och därigenom få erfarenheter som är relevanta för yrkeslivet. En grupp på åtta personer arbetade under en termin med ett projekt som handlade om utvecklingen av ett obemannat luftburet radiometrisystem. Ett lättare system efterfrågades för att förlänga flygtiden. Under utvecklingen tillämpades metoder från Semat, Scrum och Extreme Programming. Utvecklingsarbetet fungerade bra och en lösning för problemet togs fram, systemet hann dock inte implementeras full ut. Arbetet visade att ett lättare radiometrisystem är aktuellt för framtiden.

  • 36.
    Danielsson, Tina
    Linköping University, Department of Computer and Information Science, Artificial Intelligence and Intergrated Computer systems. Linköping University, Faculty of Science & Engineering.
    Portering från Google Apps REST API till Microsoft Office 365 REST API2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Stress på arbetsplatsen relaterat till många inkommande och utgående kommunikationskanaler är ett reellt problem. Applikationer som samlar alla kanaler i samma verktyg kan hjälpa till på det här området. För att förenkla vid utveckling av en sådan applikation kan ett modulärt system skapas, där varje modul ser liknande ut och enkelt kan kopplas in i en huvudapplikation. Den här studien undersöker de problem som kan uppstå när flera tjänster ska integreras, mer specifikt genom att titta på hur en befintlig modul för e-post via Google Apps kan porteras för att stödja e-post via Microsoft Office 365. Arbetet har skett enligt metoder för testdriven portering och varje steg i porteringen har dokumenterats noggrant. Ett antal problemområden har identifierats och möjliga lösningar föreslås. Utfrån de problem som uppstått dras slutsatsen att de är av en sådan karaktär att de inte utgör något hinder för en portering.

  • 37.
    Edvardsson, Jon
    Linköping University, Department of Computer and Information Science, PELAB - Programming Environment Laboratory. Linköping University, The Institute of Technology.
    Techniques for Automatic Generation of Tests from Programs and Specifications2006Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Software testing is complex and time consuming. One way to reduce the effort associated with testing is to generate test data automatically. This thesis is divided into three parts. In the first part a mixed-integer constraint solver developed by Gupta et. al is studied. The solver, referred to as the Unified Numerical Approach (una), is an important part of their generator and it is responsible for solving equation systems that correspond to the program path currently under test.

    In this thesis it is shown that, in contrast to traditional optimization methods, the una is not bounded by the size of the solved equation system. Instead, it depends on how the system is composed. That is, even for very simple systems consisting of one variable we can easily get more than a thousand iterations. It is also shown that the una is not complete, that is, it does not always find a mixed-integer solution when there is one. It is found that a better approach is to use a traditional optimization method, like the simplex method in combination with branch-and-bound and/or a cutting-plane algorithm as a constraint solver.

    The second part explores a specification-based approach for generating tests developed by Meudec. Tests are generated by partitioning the specification input domain into a set of subdomains using a rule-based automatic partitioning strategy. An important step of Meudec’s method is to reduce the number of generated subdomains and find a minimal partition. This thesis shows that Meudec’s minimal partition algorithm

    is incorrect. Furthermore, two new efficient alternative algorithms are developed. In addition, an algorithm for finding the upper and lower bound on the number of subdomains in a partition is also presented.

    Finally, in the third part, two different designs of automatic testing tools are studied. The first tool uses a specification as an oracle. The second tool, on the other hand, uses a reference program. The fault-detection effectiveness of the tools is evaluated using both randomly and systematically generated inputs.

  • 38.
    Einarsson, Bo
    et al.
    Linköping University, Department of Mathematics, Scientific Computing. Linköping University, The Institute of Technology.
    Hanson, Richard
    Visual Numerics Inc., Albuquerque, NM.
    Hopkins, Tim
    University of Kent, Canterbury, England.
    Standardized mixed language programming for Fortran and C2009In: ACM SIGPLAN Fortran Forum, ISSN 1061-7264, Vol. 28, no 3, p. 8-22Article in journal (Refereed)
    Abstract [en]

    Programmers have long practiced the matter of mixed language procedure calls. This is particularly true for the programming languages C and Fortran. The use of the alternate language often results in efficient running time or the effective use of human or other resources.

    Prior to the Fortran 2003 standard there was silence about how the two languages interoperated. Before this release there existed a set of differing ad hoc methods for making the inter-language calls. These typically depended on the Fortran and C compilers. The newer Fortran standard provides an intrinsic module, iso_c_binding, that permits the languages to interoperate. There remain restrictions regarding interoperable data types.

    This paper illustrates several programs that contain core exercises likely to be encountered by programmers. The source code is available from the first author's web site. Included is an illustration of a "trap" based on use of the ad hoc methods: A call from a C to a Fortran 2003 routine that passes a character in C to a character variable in Fortran results in a run-time error.

  • 39.
    Enström, Andreas
    et al.
    Linköping University, Department of Computer and Information Science.
    Ericsson, Joakim
    Linköping University, Department of Computer and Information Science.
    Eriksson, John
    Linköping University, Department of Computer and Information Science.
    Fagerström, Josef
    Linköping University, Department of Computer and Information Science.
    Nilsson, Olle
    Linköping University, Department of Computer and Information Science.
    Olin, Per
    Linköping University, Department of Computer and Information Science.
    Sörsäter, Michael
    Linköping University, Department of Computer and Information Science.
    Viken, Hampus
    Linköping University, Department of Computer and Information Science.
    Ett system för att detekterakundbeteende i självplockslager:As Long As It Scales2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport beskriver systemet ALAIS (As Long As It Scales) och hur det harutvecklats. ALAIS byggdes i samband med ett kandidatarbete i programvaruutvecklingvid Linköpings universitet åt företaget Valtech. Syftet med systemetär att demonstrera att det går att utföra automatiserad A/B-testning genom attplacera skålar med godis på olika vågar och se hur positionen, samt eventuellamärkningar, som ekologisk, påverkar konsumtionen. Det färdiga systemet är uppdelati tre moduler, en som sköter kommunikationen med vågarna, en som utförberäkningar och kommunicerar med en databas, och en som består av ett grafisktgränssnitt som användaren interagerar med. De tre modulerna kommunicerarmed varandra över ett nätverk. Rapporten avslutas med individuella erfarenheterfrån alla gruppmedlemmar.

  • 40.
    Erhard-Olsson, Niklas
    Linköping University, Department of Computer and Information Science, Human-Centered systems.
    Procedural Generation of 2D Levels for a Motion-based Platformer Game in Unity with Large Amount of Movement2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis mainly describes and implements a new way of analyzing motion generated when playing a motion controlled game. It also describes the implementation of automatic level generation together with the utilization of Unitys excellent new 2D tools. The motion controller used to play the prototype game is ported and implemented with Unitys own shader language and stored as a reusable prefab for any Unity project. A new specific method of analyzing the motion mapped to the level is implemented in Unity. Some game specific analysises is presented with the said method, and examples of how the method can be used for more and richer analysis’s is discussed.

  • 41.
    Eriksson, Joakim
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    Representation of asynchronous communication protocols in Scala and Akka2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis work investigates how to represent protocols for asynchronous communication in the Scala programming language and the Akka actor framework, to be run on Java Virtual Machine (JVM). Further restrictions from the problem domain - the coexistence of multiple protocol instances sharing the same Java thread - imply that neither an asynchronous call waiting for response nor anything else can block the underlying Java threads.

    A common way to represent asynchronous communication protocols is to use state machines. This thesis seeks a way to shrink the size of and to reduce the complexity of the protocol implementations by representing sequences of asynchronous communication calls (i.e. sequences of sent and received messages) as a type of procedure. The idea is find a way to make the procedures that contain asynchronous calls look like synchronous communication procedures by hiding the asynchronous details. In other words, the resulting procedure code should show what to do and not so much focus on how to overcome the impediment of the asynchronous calls.

    With the help of an asynchronous communication protocol toy example, this report shows how such an protocol can be implemented with a combination of a state machine and a procedure representation in Scala and Akka. The procedure representation hides away the asynchronous details by using the Scala capability to use CPS-transformed delimited continuations. As a sub-problem, this thesis also shows how to safely schedule asynchronous communication timeouts with help of Scala and Akka within the restrictions of the thesis problem domain.

  • 42.
    Eriksson, Oskar
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, The Institute of Technology.
    A web-based tool for managing intellectual property laws2013Independent thesis Basic level (university diploma), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    Ipendo Systems AB är ett företag som tillhandahåller en webbaserad tjänst, Ipendo Platform, för administration av immateriella rättigheter. De lagar och regler som reglerar hur immateriella rättigheterna hanteras skiljer sig från varje land och tjänsten måste då innehålla information om alla dessa. Dessa lagar eller regler, hädanefter regler, hålls uppdaterade utanför tjänsten i ett Exceldokument, därefter importeras de till Ipendo Platform manuellt. Innan det görs måste de valideras enligt förutbestämda restriktioner, detta för att de dels ska vara i rätt format för Ipendo Platform eller någonting annat som måste vara i rätt format.

    Syftet och motivationen till detta examensarbete är att man vill ersätta denna process med ett enklare webbaserat adminstrationsverktyg som låter back-office hantera och uppdatera reglerna och sedan själva utföra validering och importering. Detta gör att tid sparas och de personer som jobbar med att uppdatera regler får feedback direkt från valideringen istället för att man ska vänta på att en annan avdelning gör valideringen. Min uppgift var att undersöka hur man skulle kunna utveckla ett sådant här verktyg och framställa en prototyp som visar på hur det skulle kunna se ut och fungera. I prototypen ville man ha möjlighet för användaren att redigera reglerna i ett rutnät, i stort sett på samma sätt som i Excel, men även automatisk validering och versionshantering av regler, man skulle alltså kunna ha flera temporära versioner av samma regler.

    Redan från början visste man att det fanns ett utvecklingsverktyg som hade de grundläggande förutsättningarna att kunna utveckla ett sådant verktyg, det var Visual Studio LightSwitch. Det är ett ramverk till Visual Studio som förenklar utveckling av dataintensiva affärsapplikationer för webben samt som en vanlig skrivbordsapplikation. Examensarbetets syfte skulle sedan bli att utveckla en prototyp för administrationsverktyget med hjälp av LightSwitch, utvärdera den och sedan dra en slutsats om huruvida man borde vidareutveckla prototypen eller se sig om efter en annan utvecklingsmetod. Slutsatsen som kunde dras i slutet av examensarbetet var att prototypen utvecklad i LightSwitch fungerar bra och är användarvänlig, men det finns vissa begränsningar i utvecklingsmetoden som man bör ta ställning till om de går att förbise eller lösa. Om de inte går att lösa eller förbise bör LightSwitch eventuellt inte användas som utvecklingsmetod till den slutgiltiga utvecklingen av administrationsverktyget.

  • 43.
    Eriksson, Oskar
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Rydkvist, Emil
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    An in-depth analysis of dynamically rendered vector-based maps with WebGL using Mapbox GL JS2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The regular way of displaying maps in a web browser is by downloading raster images from a server and lay them side by side to make up a map. If any information on the map is changed, new images has to be downloaded, it cannot be done on the client. The introduction of WebGL opens up a whole new world of delivering advanced graphics content to the end user in a web browser. Utilizing this technology for displaying maps means only the source data is sent to the web browser where the map gets rendered using the device's GPU. This adds a number of benefits such as the ability of changing map appearance on the client, add new features to the map and often less data transfer. It however sets higher expectations of the client device's hardware as it needs to render the map at a high enough frame rate to not appear slow and unresponsive. This thesis investigates a framework for client side map rendering in a web browser, Mapbox GL JS, with focus on performance. It shows how map source data can be generated as well as its corresponding style rules are constructed with performance in mind. It provides benchmarking results of different map data sets with different detail intensity and shows that a device with good GPU performance is needed for an acceptable user experience. It also shows that lowering the amount of rendered detail does not necessarily result in better performance.

  • 44.
    Erkstam, David
    Linköping University, Department of Computer and Information Science.
    Projektdatabas mm2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den här rapporten behandlar ett examensarbete där målet var att programmera en projektdatabas och projektöversikt åt Milton Medicinteknik KB. Syftet var att dess projektgrupper ska kunna komma åt att granska sina filer samt se filernas relationer med varandra, genom inloggning på en hemsida. Språken som användes var MySQL för att hantera databasen, PHP för att kommunicera mellan hemsidan och webbservern, HTML för att formatera webbsidorna och ActionScript 3 som är Flash programmeringsspråk för att programmera projektöversikten.

     

    I huvuddelen av rapporten är det beskrivet hur projektöversikten och projektdatabasen fungerar. Från hemsidan kan man ladda upp filer som hanteras av projektgrupper och användare med rätt rättigheter. Det finns tre typer av behörighet som användarna kan ha: Administratör som kan skapa användare och projektgrupper, projektledare som ansvarar för sin egen projektgrupp samt vanliga användare som endast kan ladda upp och länka filer i sin egen projektgrupp. Projektöversikten tillåter att användarna på ett överskådligt sätt kan se hur filerna som de har rättighet att se är länkade med varandra, lägga till och ta bort egna filer samt se deras innehåll.

  • 45.
    Fahlander, Olov
    et al.
    Linköping University, Department of Electrical Engineering. Linköping University, The Institute of Technology.
    Wilson, Roland
    Linköping University, Department of Electrical Engineering. Linköping University, The Institute of Technology.
    Linear Codes for Real-Time Colour Graphics1980Report (Other academic)
    Abstract [en]

    In this paper, the problem of 'hidden - surface' elimination is considered. It is shown that a new linear surface- filling algorithm leads to some simple techniques for hidden-surface removal. Necessary conditions are established for three such methods to work and hard ware to implement these solutions is shown to be practicable. Each of the three proposed methods is seen to have advantages in certain circumstances - the choice between them depends very much on the nature of the graphics system in which they might be used.

  • 46.
    Falk, Daniel
    Linköping University, Department of Computer and Information Science.
    Implementation and evaluation of sensoring a user's position with React Native2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Today, there are many different ways to handle physical access control. RFID cards and tags are still a major solution but during the last years the market have been focusing on taking advantage of the devices that most people always carry with them, such as smartphones, tablets or smartwatches.

    This thesis has been carried out together with the company BRP Systems. They develop and deliver business systems to mainly the fitness business. In their product suite there is an application for booking workout sessions at these facilities.

    In this thesis their booking application has been rebuilt as a prototype and the functionality of unlocking the door and checking into workout sessions has been added. The application has been developed in React Native for Android and has been implemented in three versions using different techniques to sensor the users position at the door. The techniques are iBeacon, GPS and QR code. The iBeacon- and GPS versions work by allowing the user to unlock the door when standing outside it. A local notification will be pushed if the application is in the background. The QR code version allows the user to scan a QR code at the door to unlock it. When the door has been unlocked the users can also check into their booked workout sessions. The system and the different versions have been tested at one of BRP Systems customers to evaluate the usability.

    The conclusion is that an application with high usability can be built with all tested techniques in React Native. For the system to be used several other factors such as security and maintenance has to be considered. The choice to use React Native might be of high risk since it is a relatively new framework relying on community developed libraries.

  • 47.
    Falk, Joakim
    Linköping University, Department of Computer and Information Science, Human-Centered systems.
    Usability guided development of a participant database system2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    This project consisted of the development of a web based participant database system to replace a spreadsheet based one for the project “Vi Ses! Språkvänner i Linköping” and the evaluation of it. The design and implementation was done iteratively using a collection of usability guidelines as well as the results of a set of user tests. User tests were also used for the evaluation of the web database system. The task during the user tests was participant matching and the main measurement taken was task completion time.

    The project resulted in a web database system that could fully replace the spreadsheet database system. The evaluation tests showed that this system was both faster to match participants in as well as less error prone.

  • 48.
    Faur, Andrei
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    Memory Profiling Techniques2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Memory profiling is an important technique which aids program optimization and can even help tracking down bugs. The main problem with the current memory profiling techniques and tools is that they slow down the target software considerably therefore making them inadequate for mainline integration. Ideally, the user would be able to monitor memory consumption without having to worry about the rest of the software being affected in any way. This thesis provides a comparison of existing techniques and tools along with the description of a memory profiler implementation which tries to provide a balance between the information it is able to retrieve and the influence it has on the target software.

  • 49.
    Fleming, Theodor
    Linköping University, Department of Computer and Information Science, Software and Systems.
    Decentralized Identity Management for a Maritime Digital Infrastructure: With focus on usability and data integrity2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When the Internet was created it did not include any protocol for identifying the person behind the computer. Instead, the act of identification has primarily been established by trusting a third party. But, the rise of Distributed Ledger Technology has made it possible to authenticate a digital identity and build trust without the need of a third party. The Swedish Maritime Administration are currently validating a new maritime digital infrastructure for the maritime transportation industry. The goal is to reduce the number of accidents, fuel consumption and voyage costs. Involved actors has their identity stored in a central registry that relies on the trust of a third party. This thesis investigates how a conversion from the centralized identity registry to a decentralized identity registry affects the usability and the risk for compromised data integrity. This is done by implementing a Proof of Concept of a decentralized identity registry that replaces the current centralized registry, and comparing them. The decentralized Proof of Concept’s risk for compromised data integrity is 95.1% less compared with the centralized registry, but this comes with a loss of 53% in efficiency.

  • 50.
    Fritzson, Peter
    et al.
    Linköping University, Department of Computer and Information Science.
    Pop, Adrian
    Linköping University, Department of Computer and Information Science.
    Broman, David
    Linköping University, Department of Computer and Information Science.
    Aronsson, Peter
    Linköping University, Department of Computer and Information Science.
    Formal Semantics Based Translator Generation and Tool Development in Practice2009In: Proceedings of  20th Australian Software Engineering Conference (ASWEC 2009), Gold Coast, Queensland, Australia, April 14 – 17, 2009, IEEE Computer Society , 2009, p. 256-266Conference paper (Refereed)
    Abstract [en]

    In this paper we report on a long-term research effort to develop and use efficient language implementation generators in practice. The generator is applied to a number of different languages, some of which are used for projects in industry. The used formal specification style is operational semantics, primarily in the form called natural semantics, represented and supported by a meta-language and tool called the relational meta language (RML), which can generate efficient implementations in C, on par with hand-implemented code. Generating implementations from formal specifications are assumed to give advantages such as: high level descriptions, higher degree of correctness, and consistency between specification and implementation. To what extent can this be realized in practice? Does it scale to large language implementations? To answer some of these questions we have developed specifications of a range of languages: imperative, functional, object-oriented (Java), and equation-based (Modelica). The size of specifications range from half a page to large specifications of 60 000 lines. It turns out to be possible to generate efficient compilers, also for large languages. However, the performance of the generator tool and the user support of the development environment become increasingly important for large specifications. To satisfy such user needs the speed of the generator was increased a factor of ten to reduce turn-around time, and an Eclipse plug-in including a debugger were developed. For very large specifications, the structuring and modularity of the specification itself also become essential for performance and maintainability.

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