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  • Johansson, Max
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Optimal Control of Heat Transfer Rates in Turbochargers2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • Fredén, Linnéa
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    The Impact of Abiotic Stress on Alternative Splicing in Lipid Transfer Protein in Marchantia polymorpha2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    All plants have a protection against the surrounding environment called a cuticle coating. When this cuticle coating is constructed it is believed that the family of protein called lipid transfer proteins (LTPs) is involved. The LTPs are small and cysteine rich. In Marchantia polymorpha the groups of LTPs called LTPd and LTPg can be found. 8 and 4 in each group respectively. In the genes of LTPd there is an intron placed downstream of the start codon. Firstly, a sequence database search was performed and LTPd2 and LTPd3 were chosen for further experiments in this study. Secondly, a control that the intron was present in the samples were done by preforming a PCR reaction of cDNA from isolated RNA taken from untreated Marchantia polymorpha. A gel electrophoresis of the product was also performed. Lastly, the amount of alternative splicing in LTPd2 and LTPd3 from Marchantia polymorpha after treated with cold and dehydration were studied using quantitative PCR. For the qPCR MpACT and the exon of respective gene were used as references. The ΔCt values and the expression fold (2ΔΔCt) calculated from the qPCR results showed that most of the transcript with introns preserved were upregulated after subjected to stress. Only the intron in MpLTPd2 and MpLTPd3 with MpACT as reference showed a small downregulation after the cold treatment. The intron in MpLTPd3 with MpLTPd3s exon as reference didn’t show any difference. None of the intron transcript in any of the genes on the other hand showed any significant difference in the alternative splicing. This could be because of small sample groups when the test was performed. In conclusion, there were no significant difference in intron expression between treated and control samples. Therefore, nothing can be said about the change in alternative splicing in MpLTPds after cold and dehydration treatments.

  • Fritzell, Gustav
    et al.
    Linköping University, Department of Management and Engineering, Economics.
    Strand, Liam
    Linköping University, Department of Management and Engineering, Economics.
    The Opportunity Cost Neglect of Money and Time: The Role of Mental Budgeting2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Consumers often fail to consider the alternative ways to spend money when making decisions to buy consumer goods, this is called opportunity cost neglect. In this experimental study, our objective was to replicate the previous research of Frederick et al. (2009) showing that reminding individuals about the opportunity cost affects their decisions. Furthermore, we also wanted to extend the knowledge about this behavior by investigating whether individuals neglect the opportunity cost when making financial decisions or decisions about time allocation. In addition, we hypothesized that individuals who conduct mental budgeting (i.e., they categorize-, budget-, and track expenditures to mental accounts), are more likely to neglect the opportunity cost since they do not treat money as fungible.

    In an online experiment, we measured how being reminded about the opportunity cost would affect the probability of an individual buying a cheap and an expensive consumer goods, of investing money, and of watching a movie. Furthermore, we measured how being reminded about the opportunity cost affects the decision of those who conduct mental budgeting and those who do not. Our results showed that individuals neglect opportunity cost of the expensive consumer good and time (p=0.1). We found a positive relation between conducting mental budgeting and opportunity cost neglect for the expensive consumer good (p=0.1) and the deposit account (p=0.05), but no such effect in the other three scenarios.

    Our results imply that, due to opportunity cost neglect of time, people might be even further from optimal decision making than previously suggested since it extends to decisions about time allocation, and perhaps to investments; and people who conduct mental budgeting sometimes spend less/save more when reminded about the opportunity cost.

  • Karlsson, Henrik
    et al.
    Linköping University, Department of Management and Engineering, Solid Mechanics.
    Gustavsson, Joakim
    Linköping University, Department of Management and Engineering, Solid Mechanics.
    Stabilitetsanalys av ledstaplartruck med avseende på tippning: En FEM-baserad metod för heltrucksmodeller2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose has been to analyze a modelling process based on the finite element method (FEM), for a powered stacker truck of the model SPE 140 TX HILO. It was analyzed how such a model should be designed in order to perform stability analyses. This was done by analyzing which of the trucks components that were relevant from a stability perspective. These components were analyzed in order to figure out which modelling approach that was best suited to model the components in a FEM-software. The result of these analyses is a modelling methodology describing which approach that should be used during the entire modelling process of a FEM-model consisting of an entire truck.

  • Ivarsson, Adam
    Linköping University, Department of Computer and Information Science.
    Expediting Gathering and Labeling of Data from Zebrafish Models of Tumor Progression and Metastasis Using Bespoke Software2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    In this paper I describe a set of algorithms used to partly automate the labeling and preparation of images of zebrafish embryos used as models of tumor progression and metastasis. These algorithms show promise for saving time for researchers using zebrafish in this way.

  • Haglund, Pontus
    et al.
    Linköping University, Department of Computer and Information Science.
    Karlsson, Victor
    Linköping University, Department of Computer and Information Science.
    HTML5 as a platform independent tool to render IoT-data2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    This paper explores advantages and challenges of specifying how IoT data is presented to an end user in AR using HTML5. Our conclusion is that HTML5 is a way of defi- ning data where competence is easy to come by and cross platform usability is good. The primary advantage is the capability of deciding how something is rendered and have it look the same way on any number of different platforms. The challenges are that cross platform compatibility is not perfect. Even platforms such as a native Android application, that has support for rendering HTML, suffered from very poor performance compared to a PC. Platforms not supporting HTML5 natively, in this case Unity and Vuforia, caused further challenges and required a separate headless browser application to render the web page. Our conclusion is that you can use HTML5 to define the appearance of data visualization across multiple platforms, even though they may have no native support for rendering the DOM. It worked without issues within a browser running on a PC, came with performance issues inside an Android webview and required additional middleware and limited interaction in Unity.

  • Odd, Joel
    et al.
    Linköping University, Department of Computer and Information Science.
    Theologou, Emil
    Linköping University, Department of Computer and Information Science.
    Utilize OCR text to extract receipt data and classify receipts with common Machine Learning algorithms2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    This study investigated if it was feasible to use machine learning tools on OCR extracted text data to classify receipts and extract specific data points. Two OCR tools were evaluated, the first was Azure Computer Vision API and the second was Google Drive REST Api, where Google Drive REST Api was the main OCR tool used in the project because of its impressive performance. The classification task mainly tried to predict which of five given categories the receipts belongs to, and also a more challenging task of predicting specific subcategories inside those five larger categories. The data points we where trying to extract was the date of purchase on the receipt and the total price of the transaction. The classification was mainly done with the help of scikit-learn, while the extraction of data points was achieved by a simple custom made N-gram model.

    The results were promising with about 94 % cross validation score for classifying receipts based on category with the help of a LinearSVC classifier. Our custom model was successful in 72 % of cases for the price data point while the results for extracting the date was less successful with an accuracy of 50 %, which we still consider very promising given the simplistic nature of the custom model.

  • Bergstrand, Fredrik
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems.
    Edqvist, Tobias
    Linköping University, Department of Computer and Information Science, Software and Systems.
    Performance Optimizing Priority Assignment in Embedded Soft Real-time Applications2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Optimizing task priority assignments is a well-researched area in the context of hard real-time systems, where the goal in the majority of cases is to produce a priority assignment that results in a schedulable task set. The problem has also been considered, albeit not to the same extent, in the soft real-time context where quality of service metrics determine the overall performance of systems. Previous research on the problem in the soft real-time context often resorts to some analytical approach, with the drawback of having to put relatively strict constraints on the system models to avoid excessively complex analysis computations. As a consequence, many attributes of a real system have to be omitted, and features such as multi-processor hardware platforms might make the analytical approach unfeasible due to complexity issues. In this thesis we took a different approach to the problem and used discrete event simulation to drive the priority assignment optimization process, which enabled more complex system models at the cost of increased objective function evaluation times. A latency-related quality of service metric was used as the objective function in a tabu search based optimization heuristic. Improvements were observed in both simulation and in the real system that was modeled. The results show that the model successfully captured key attributes of the modeled system, and that the discrete event simulation approach is a viable option when the goal is to improve or determine the quality of service of a soft real-time application.

  • Axelsson, Victor
    et al.
    Linköping University, Department of Computer and Information Science.
    Bucht, Sebastian
    Linköping University, Department of Computer and Information Science.
    Hellmark Carrasco, Michelle
    Linköping University, Department of Computer and Information Science.
    Fridell, Gustav
    Linköping University, Department of Computer and Information Science.
    Hagel, Sofia
    Linköping University, Department of Computer and Information Science.
    Larsson, Pontus
    Linköping University, Department of Computer and Information Science.
    Olaussen, Jonas
    Linköping University, Department of Computer and Information Science.
    Ståhl, Erik
    Linköping University, Department of Computer and Information Science.
    ITREA – Utveckling av framtidens digitala annonseringsplats2018Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    This study has investigated the development of a web application in the form of a digital marketplace for IT services. The problem statement addresses how a web application of this kind can be designed to achieve three criteria; high usability, good user experience and high credibility. These factors are important to attract users to the web application, and in this way connect contractors and outsourcers for IT services. The web application has been tested iteratively during the development process to corroborate whether the implementation achieves the three criteria. This process has led to a final result of a web application that, according to performed tests, meets these criteria. A high navigability on the web application has been achieved through implementing a layout based on the four primary objectives of navigability and on a distinct connection between all pages. Furthermore, the web application’s readability has been developed with a distinct vocabulary and a font adapted to the operating system and unit the web application is run on. An appealing design has been formed through implementing a layout with color selection based on theory, that strengthens the user’s impression of the application. A responsive design has been implemented by having both a well-adapted layout and appropriate content. The web application’s high credibility has been formed by forging the application based on the seven guidelines for credibility. The conclusion drawn is that the method that has been presented is applicable to achieve the three criteria; usability, user experience and credibility. This conclusion does not only apply to web applications in the form of digital marketplaces, but also to web applications in general. 

  • Berggren, Oskar
    et al.
    Linköping University, Department of Computer and Information Science.
    Davidsson, Maria
    Linköping University, Department of Computer and Information Science.
    Hakegård, Viktor
    Linköping University, Department of Computer and Information Science.
    Jonsson, Nils
    Linköping University, Department of Computer and Information Science.
    Luu, Katarina
    Linköping University, Department of Computer and Information Science.
    Nyman, Lowe
    Linköping University, Department of Computer and Information Science.
    Woxén, Gustav
    Linköping University, Department of Computer and Information Science.
    Utformning av en e-butik för överproducerad mat med fokus på god navigerbarhet2018Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
  • Jonsson, Nils
    et al.
    Linköping University, Department of Computer and Information Science.
    Nyman, Lowe
    Linköping University, Department of Computer and Information Science.
    Davidsson, Maria
    Linköping University, Department of Computer and Information Science.
    Luu, Katarina
    Linköping University, Department of Computer and Information Science.
    Hakegård, Viktor
    Linköping University, Department of Computer and Information Science.
    Berggren, Oskar
    Linköping University, Department of Computer and Information Science.
    Woxén, Gustav
    Linköping University, Department of Computer and Information Science.
    Utformning av en e-butik för överproducerad mat med fokus på god navigerbarhet2018Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport undersöker hur en e-butik kan utvecklas för att uppnå god navigerbarhet med avseende på användarens subjektiva upplevelse. Med grund i befintlig vetenskaplig teori inom området användbarhet med fokus på navigerbarhet har en e-handelsplattform för försäljning och handel av överproducerad mat i form av matlådor utvecklats. Under utvecklingen som genomförts med en iterativ projektmetod har användartest genomförts. Resultaten från dessa användartest har sedan tillsammans med den vetenskapliga teorin använts i den fortsatta utvecklingen av webbapplikationen. Med utgångspunkt i resultat från användartester och vetenskaplig teori har frågeställningen ”Hur kan en webbapplikation ämnad som handelsplattform mellan restauranger och konsumenter för försäljning av överproducerad lunch utformas för att uppnå god navigerbarhet med avseende på användarens subjektiva upplevelse?” undersökts och besvarats. Det konkluderades att en viktig aspekt för navigerbarhet är att användaren ständigt är medveten om var i navigationsträdet denne befinner sig. Samtidigt bör det vara tydligt när och var användaren navigerar på applikationen vilket bland annat kan underlättas genom animationer eller färgmarkeringar i navigationsfältet. Det visade sig också vara viktigt att omdirigera användaren till relevanta platser på applikationen efter nyttjandet av viss funktionalitet. Vidare drogs slutsatsen att trasiga eller otydliga länkar reducerade den upplevda navigerbarheten. Länkar bör alltså utföra förväntad funktionalitet. En annan viktig faktor som påverkar navigerbarhet är vilken information som delges användaren och på vilket sätt denna presenteras. 

  • Bahadori, Kazem
    et al.
    Linköping University, Department of Computer and Information Science.
    Eklund, Herman
    Linköping University, Department of Computer and Information Science.
    Göransson, Carl
    Linköping University, Department of Computer and Information Science.
    Johansson, Henrik
    Linköping University, Department of Computer and Information Science.
    Lindau, Jakob
    Linköping University, Department of Computer and Information Science.
    Seller, Martin
    Linköping University, Department of Computer and Information Science.
    Sjögren, Linnea
    Linköping University, Department of Computer and Information Science.
    Wolf, Matilda
    Linköping University, Department of Computer and Information Science.
    MittÄrDitt - Sharing is Caring: A case study in developing simple web applications that are perceived as trustworthy by their users2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study was to create a web application that provided peer to peer rental solutions for students and while doing so maximize the usability of the application with regards to simplicity and online trust. An initial market survey was conducted, see appendix B, and the overall results were promising. The few survey takers that were hesitant towards the idea thought that using a rental solution would not be worth the while. Hence the research question focused on maximizing usability in regards to simplicity and online trust in order to make the e-shop an easy rental solution to use. The application was developed in three iterations and through the development process user tests were conducted and metrics regarding simplicity and perceived online trust were collected. The test conducted made use of the concurrent think aloud procedure, retrospective probing, surveying and time data used for calculating the effectiveness and efficiency of the test participants. The test results all improved throughout the development process and the application was perceived as both simple and trustworthy by test participants. By the end of the study, an application that could provide a peer to peer rental solution that was trusted by its users and was simple to use was realized. The study concluded that the evaluation methods used were good indicators of whether a web application is simple and trustworthy by identifying issues with the application as well as the improvements reflected in the test results. However they should have been applied on separate test occasions.

  • Björk, Julius
    et al.
    Linköping University, Department of Computer and Information Science.
    Blidholm, Jennifer
    Linköping University, Department of Computer and Information Science.
    Gerdin Börjesson, Fredrik
    Linköping University, Department of Computer and Information Science.
    Edenheim, Arvid
    Linköping University, Department of Computer and Information Science.
    Ingvarsson, Annie
    Linköping University, Department of Computer and Information Science.
    Lindstedt, Stefan
    Linköping University, Department of Computer and Information Science.
    Onsjö, Johan
    Linköping University, Department of Computer and Information Science.
    Söderberg, Pär
    Linköping University, Department of Computer and Information Science.
    En undersökning av effekten av on-site-faktorer vid sökmotoroptimering2018Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    The significance of search engine optimization is clearly highlighted sin- ce over 90 % of internet usage starts with a search engine according to contemporary studies, whilst the internet also has contributed to increa- sed competition between companies operating from different geographic markets. Guidelines from search engines and theory from studies descri- be several internal influencing factors, on-site factors, but ambiguous in the studies is how much these factors affect the ranking. For this reason, a study was conducted regarding the e-commerce platform Sparket.se and its ranking on Google through iterative testing and measurement of each on-site factor. The result and conclusion of the study suggest that key- words and structure are of greatest importance in on-site optimization. The largest improvement was observed when keywords were placed in the HTML code and accounted for 2-5 % of the total content, without duplication. A clear hierarchical structure of even width and depth also resulted in an advancement. Implementation of breadcrumbs again pro- vided limited improvement, likely because of Sparket’s small size, and sitemap, as well as robots.txt, yielded unchanged ranking. The overall effect of the on-site factors in search engine optimization was significant for the e-commerce platform.

  • Dahlström, Felicia
    et al.
    Linköping University, Department of Computer and Information Science.
    Eirik, Funnemark
    Linköping University, Department of Computer and Information Science.
    Gudmundsson, Tomas
    Linköping University, Department of Computer and Information Science.
    Lindberg, Sophie
    Linköping University, Department of Computer and Information Science.
    Nilsson, Filip
    Linköping University, Department of Computer and Information Science.
    Olsson, Marcus
    Linköping University, Department of Computer and Information Science.
    Svensk, Herman
    Linköping University, Department of Computer and Information Science.
    Sörensen, Joakim
    Linköping University, Department of Computer and Information Science.
    Baljangåvan: Omtanke på distans: Hur kan en webbapplikation som säljer enkla gåvor utformas så att den upplevs navigerbar, tillförlitlig och har en effektiv köpprocess?2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • Johansson, Viktor Alberto
    Linköping University, Department of Management and Engineering, Political Science.
    Navigating the Eastern Mediterranean: Interest-formation & State-action: Egypt, Israel, Turkey & the Republic of Cyprus2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study examines interest-formation and state-action in the Eastern Mediterranean countries of Egypt, Israel, Turkey and the Republic of Cyprus. In seeking answers to the questions on how interests of the respective countries can be explained, particularly within the area of natural gas, and possible consequences of different regional approaches, the study draws upon ideas in classical, structural, neoclassical realism and constructivism. The theoretical diversity enables the study to focus on international, state and domestic levels by way of qualitative content analysis as the selected methodology. The findings suggest that Egypt, Israel and Cyprus possess corresponding views in their regional outlook; including natural gas as a means for stability and economic growth, but also that these views contrast significantly with Turkey’s regional perspective. Additional findings show that interest-formation in all four states, despite coherence among Egypt, Israel and Cyprus, differentiates to a large degree. The chief reason is that interest-formation appears to occur within international, state and domestic levels. Regarding the second question, the study finds that the different and often conflicting regional approaches on natural gas of Cyprus and Turkey, which are based upon fundamentally different premises, pose risk for heightened tensions between both Cyprus, Turkey and the Turkish Republic of Northern Cyprus. 

  • Wisén, Ann-Charlotte
    et al.
    Linköping University, Department of Behavioural Sciences and Learning.
    Stolt Olsson, Helena
    Linköping University, Department of Behavioural Sciences and Learning.
    Inställning till anställning: En kvalitativ intervjustudie om nyanställdas upplevelse av socialisation i en statlig och en privatverksamhet2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Starting a new employment is a challenge filled with emotions such as expectationand joy but also of uncertainty and stress. Depending on the response from managerand colleagues, as well as how the organization works with the introductory process,the possibility of organizational socialization for the new employee is affected. Thepurpose of our study has been to through semi‐structured interviews study how socializationis perceived for new employees in a government organization and in a privatebusiness. Based on previous research about introduction, onboarding processesand organizational socialization, we have used theories from, among others, Mead,Cooley, Bauman and Asplund to understand and interpret the statements of the informants.The results of the study demonstrate the importance of a formal introductoryprogram for the new employee but also the importance of being well treated inorder of to delivering according to expectations and willingness to stay at the newworkplace. In comparisons between the government and the private organization it isstated that the need for security and feeling welcome is independent of whether youwork state or private.

  • Strömberg, Isak
    Linköping University, Department of Electrical Engineering, Computer Vision.
    Characterization of creping marks in paper2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The cost and environmental damage of reclaims is a large problem within thepaper industry. With certain types of paper, so called crepe marks on the paper’ssurface is a common issue, leading to printing defects and consequentlyreclaims. This thesis compares four different image analysis methods for evaluatingcrepe marks and predicting printing results. The methods evaluated consistsof one established methods, two adaptations of established methods andone novel method. All methods were evaluated on the same data, topographicheight images of paper samples from 4 paper rolls of similar type but differingin roughness. The method based on 1D Fourier analysis and the method basedon fully convolutional networks performs best, depending on if speed or detailedcharacteristics is a priority.

  • Larsson, Mattias
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems.
    Modular SoC-design: Minimizing area and power consumption2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This is the main report for Mattias Larsson’s degree project for the Master’s programin System-on-Chip. The main part of this project has been to design a modularMPSoC-unit (Multi Processor System on Chip) for reuse in different typesof projects. A SoC includes and interconnects a processor and FPGA in one chip.MPSoC is an extension of SoC including more than one processor. Zynq Ultra-Scale MPSoC has been used in this design which comes in three different versionsCG, EG and EV. In this project the EG version has been used, this versionhas a quad-core ARM Cortex-A53 platform, two Cortex-R5 real-time processorand Mali-400 MP2 graphics processing unit.The modular MPSoC-unit is designed to be used in a project as the main computingunit. A modular unit has to be general enough to fit almost all demandsbut as small as possible. The area usage is always an important question butsince the modular MPSoC-unit will be designed once and have a certain size andshape its overall area coverage determines how usable it will be. It is thereforhighly important to keep the area as small as possible.This project has been focused on the design of a modular SoC-unit with focuson a schematic-level. This report raises and answers question as too which extentsit is worth using certain types of DC/DC regulators, on-chip functionalityetc. A big part of the design work has been dedicated towards the DC/DC regulationand generation of voltages to supply the circuits. The MPSoC requires anumber of voltage levels of which some supplies can be tied together while othersare analog and sensitive to digital switching noise on the supply. This reportinvestigates the possibilities to use a simple ferrite bead filter for sensitive loadssharing the same supply. Extra work has gone into trying to reduce the numberof regulators. In order to design a safe and general power supply an estimation ofthe power consumption has to be done. This report shows how to find, use and estimatethe power consumption for the main power consumer in the system. Withthis information a generic modular SoC-design approach can be found.

  • Andersson, Fredrik
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Andersson, Hampus
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Numerical Optimal Control of Hybrid Electric Trucks: Exhaust Temperature, NOx Emission and Fuel Consumption2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The controls for a parallel hybrid electric truck are optimized using numerical optimal control. Trade-offs between catalyst light-off times, NOx emission and fuel consumption have been investigated for cold starts at two operating points, as well as temperature differences between conventional and hybrid powertrains during WHTC (World Harmonized Transient Cycle). A model describing the temperature dynamics of the aftertreatment system is implemented as well as temperature-based deNOx performance for both Cu-Zeolite and Fe-Zeolite catalysts. Control is performed in a piecewise linear fashion, resulting in a total of 23 states including control signals. It is shown that high temperatures can be a larger threat to catalyst performance when running the WHTC than low temperatures, for both conventional and hybrid powertrains. Furthermore, decreasing the light-off time of the catalyst does not always lead to decreased NOx emission, instead there is a trade-off between light-off time and NOx emission. It is found that there are controls that will realize decreased NOx emission for a hybrid truck during cold starts at the expense of increased fuel consumption.

  • Geneid, Ahmed
    et al.
    Department of Otolaryngology and Phoniatrics – Head and Neck Surgery, Helsinki University Hospital and University of Helsinki, Finlan.
    Laukkanen, Anne-Maria
    Speech and Voice Research Laboratory, School of Education, University of Tampere, Finland.
    Eklund, Robert
    Linköping University, Department of Culture and Communication, Language and Literature. Linköping University, Faculty of Arts and Sciences.
    McAllister, Anita
    Division of Speech and Language Pathology, Karolinska Institutet, Sweden.
    Kulning: A study of the physiological basis for long-distance sound propagation in Swedish cattle calls2018In: Proceedings of FONETIK 2016, KTH Royal Institute of TechnologyStockholm, Sweden8-10 June 2016 / [ed] Jens Edlund, Stockholm: Royal Institute of Technology , 2018, p. 25-30Conference paper (Other academic)
    Abstract [en]

    The Swedish cattle call song, kulning, is an example of very marked and far-reaching sound propagation of vocal communication. While earlier studies have investigated the acoustic characteristics of kulning, the present study focuses on its physiological basis from the point of view of vocal fold functionand supralaryngeal posture by applying electroglottography and stroboscopy to two types singing: falsetto (head voice)and kulning. It is shown that kulning, ascompared to falsetto, exhibits a better contact of the vocal folds and a longer glottal closure in the phonation cycle. Nasofiberendoscopy also showedmedial and anteroposterior narrowing of the laryngeal inlet and approximation of the false vocal folds in kulning.

  • Albinsson, Hannes
    et al.
    Linköping University, Department of Computer and Information Science.
    Bengtsson, Emil
    Linköping University, Department of Computer and Information Science.
    Survey data visualization in a web environment2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Briteback Explore is a service provided by the company Briteback. The service provides a survey tool to its users that allows access to results through the downloading of a comma-separated values (CSV) -file. What was built was a visualization model that provides the survey tool’s users with a graphical representation of the data directly through the service. Providing an overview of the survey results that lessens the amount of information overload perceived by the user while giving the data a structure. A survey based off of the System Usability Scale (SUS) evaluation method was then performed to display to what degree users found the new feature usable. Results showed a satisfactory high score on the SUS adjective rating scale.

  • Arnström, Daniel
    Linköping University, Department of Electrical Engineering, Automatic Control.
    State Estimation for Truck and Trailer Systems using Deep Learning2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    High precision control of a truck and trailer system requires accurate and robust state estimation of the system.

    This thesis work explores the possibility of estimating the states with high accuracy from sensors solely mounted on the truck. The sensors used are a LIDAR sensor, a rear-view camera and a RTK-GNSS receiver.

    Information about the angles between the truck and the trailer are extracted from LIDAR scans and camera images through deep learning and through model-based approaches. The estimates are fused together with a model of the dynamics of the system in an Extended Kalman Filter to obtain high precision state estimates. Training data for the deep learning approaches and data to evaluate and compare these methods with the model-based approaches are collected in a simulation environment established in Gazebo.

    The deep learning approaches are shown to give decent angle estimations but the model-based approaches are shown to result in more robust and accurate estimates. The flexibility of the deep learning approach to learn any model given sufficient training data has been highlighted and it is shown that a deep learning approach can be viable if the trailer has an irregular shape and a large amount of data is available.

    It is also shown that biases in measured lengths of the system can be remedied by estimating the biases online in the filter and this improves the state estimates.

  • Anshelm, Jonas
    et al.
    Linköping University, Department of Thematic Studies, Technology and Social Change. Linköping University, Faculty of Arts and Sciences.
    Haikola, Simon
    Linköping University, Department of Thematic Studies, Technology and Social Change. Linköping University, Faculty of Arts and Sciences.
    Depoliticization, Repoliticization, and Environmental Concerns: Swedish Mining Politics as an Instance of Environmental Politicization2018In: ACME: An International E-Journal for Critical Geographies, ISSN 1492-9732, E-ISSN 1492-9732, Vol. 7, no 2Article in journal (Refereed)
    Abstract [en]

    An argument within the wider theory of postpolitics that has gained traction over the last decade is that environmental concerns in general, and climate policy in particular, are especially conducive to depoliticization. In this paper, we take issue with this notion by presenting an empirical case study of the repoliticization of Swedish mining and then, on the basis of this analysis, offer theoretical reflections on how to better understand depoliticization and repoliticization of the environment. We argue for the use of a narrow definition of 'depoliticization', and that sufficient attention must be paid to temporal and scalar differentiation of continuous processes of de- and repoliticization, and that normative assumptions of what constitutes the genuinely political should be abandoned. We argue that environmental concerns harbour large potential for effective politicization, and that this politicization occurs as a response to depoliticization, through concurrent, cross-fertilizing and intertwined processes of repoliticization across scales both inside and outside of formal channels of government, whereby previously depoliticized state agencies may become crucial.

  • Carlsson, Louise
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Identifying variation in the OMT gene in Pisum sativum and its relevance regarding protein content2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    As global meat consumption is rising, the negative impact the animal husbandry sector has on the environment will increase. Greenhouse gas emissions have increased by 40 % during the last 200 years, and the animal husbandry sector is today responsible for 18 % of the total greenhouse gas emissions from food production. More environmentally friendly protein sources, such as soy and pea, must therefore be developed. Pisum sativum can (unlike the most popular meat alternative – soy) be grown all over Europe and might thus be a good alternative that allows for locally sourced alternatives to meat protein. Identifying genes with important agricultural properties might aid the development of pea cultivars with a more reliable protein content. One such gene was hypothesised to be the OMT gene, which is strongly expressed during the embryonic development of P. sativum and seems involved in functions such as seed storage and protein synthesis. Thirty-one accessions of P. sativum were tested to see if different improvement types differed from each other regarding protein content and seed weight, but no such differences were found. DNA was extracted from all accessions, sequenced, and successful sequences were tested to determine if variation in the gene correlated with protein content. Two haplotypes were identified, but there was no correlation between them and protein content found. Based on the results of this study, there is little evidence that the OMT gene correlates with protein content in the studied accessions.  

  • Persson, Anna
    Linköping University, Department of Physics, Chemistry and Biology.
    Non-vitamin K dependent oral anticoagulants (NOACs) controls2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In recent years non-vitamin K dependent oral anticoagulants (NOACs) have started to replace warfarin for treatment and prevention of deep venous thrombosis (DVT), pulmonary embolism (PE) and stroke in patients with and without atrial fibrillation. There is a need for a simple and rapid method to detect the presence of these drugs in patient plasma. To meet these new demands, MediRox is developing a screening assay based on a novel prothrombin time (PT) method for rapid detection of NOACs in plasma. The assay is semi-quantitative and by dividing the International Normalised Index (INR) from a NOAC sensitive PT method with the INR from a NOAC insensitive PT method, NOAC containing samples be detected while plasma from normal donors and with warfarin are excluded.

     

    The purpose of this project is to develop prototypes of assay quality controls for detection of NOACs in plasma.

     

    The results show that the method used for the NOAC control prototypes is applicable and the PT ratio is comparable to patient samples for the low, medium and high concentrations of NOAC. The effect of lyophilisation indicates that the PT ratios for the NOAC control prototypes were nearly unaffected by the lyophilisation. The in-use stability at room temperature (20-25oC) for all NOAC control prototypes were at least 24 hours.

     

    The methodology for production needs to be further optimised to increase the commutability to patient samples with very high concentrations of NOAC. The data indicates that the effect of lyophilisation is minimal and the stability of the NOAC control prototypes are satisfying, which is promising for future product development of NOAC controls. 

  • Blomqvist, Samuel
    et al.
    Linköping University, Department of Computer and Information Science.
    Thorén, Daniel
    Linköping University, Department of Computer and Information Science.
    Peters, Christopher
    Linköping University, Department of Computer and Information Science.
    Sjöblom, William
    Linköping University, Department of Computer and Information Science.
    Malmfors, Fredrik
    Linköping University, Department of Computer and Information Science.
    Willquist, André
    Linköping University, Department of Computer and Information Science.
    Westerdahl, Ludvig
    Linköping University, Department of Computer and Information Science.
    DQ - Digitalt biljettsystem2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med denna rapport är att redovisa utvecklingen av ett digitalt biljettsystem som skulla användas av studentföreningar vid Linköpings universitet. Systemet utvecklas av studenter vid Linköpings universitet på uppdrag av individer representerande LinTek och StuFF, två kårer vid universitetet. Målet med projektet är att utveckla ett digitalt kösystem som studenter vid Linköpings universitet kan använda för att köpa biljetter till fester eller liknande. Resultatet av projektet är ett i många aspekter fungerande system som dock saknar vissa grundläggande aspekter. Utöver det utvecklade systemet har även denna rapport skrivits inklusive en individuell del per gruppmedlem som går in på djupet i olika områden relaterade till projektet.

  • Wadström, Christoffer
    et al.
    Linköping University, Department of Management and Engineering, Economics.
    Wittberg, Emanuel
    Linköping University, Department of Management and Engineering, Economics.
    Renewable energy and economic growth in Canada and the U.S.: – A nonlinear tale of two countries2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Several scholars have highlighted that energy consumption in general and consumption of renewable energy in particular may be a potential driver of economic growth. In this paper we examine the relationship between renewable energy production and economic activity in Canada, between May 1966 to December 2015, and in the U.S., between January 1973 to December 2015. By applying quantile causality, we take a nonlinear approach considering all quantiles of the distribution, analysing monthly data containing renewable energy production and Industrial Production Index. We find evidence of a nonlinear relationship in both Canada and the U.S., indicating that widely used linear models fail to describe important aspects of the renewable energy-economic growth nexus. The main Canadian results imply a unidirectional relationship from Industrial Production Index to renewable production in most quantiles of the distribution which supports the Conservation hypothesis. However, we also find weak evidence of a bi-directional relationship, which supports the Feedback hypothesis, for the lower and higher quantiles. This may indicate the renewable energy drives economic growth for some market conditions in Canada. For the U.S. we find evidence of a weak and negative feedback relationship between renewable energy and industrial production, indicating an inefficient production of renewable energy which not is well integrated in the overall energy system. Based on theory concerning the potential benefits of renewable energy, the minor role of renewable energy production in Canada and the U.S. could be a result of institutional barriers and absence of supporting infrastructure. Both countries need policies directed to overcome these barriers in order to benefit from the potential of renewable energy.

  • Faskunger, Johan
    et al.
    Proactivity AB.
    Szczepanski, Anders
    Linköping University, Department of Culture and Communication, Culture and Aesthetics. Linköping University, Faculty of Educational Sciences.
    Åkerblom, Petter
    Institutionen för stad och land, Sveriges lantbruksuniversitet.
    Klassrum med himlen som tak: En kunskapsöversikt om vad utomhusundervisning betyder för lärande i grundskolan2018Report (Other academic)
    Abstract [sv]

    Kunskapsöversikten bygger på en genomgång av resultat och slutsatser från vetenskapliga och systematiska översikter där författarna sammanställt forskning som belyser hur skolprestationer främst bland barn i grundskoleålder påverkas av utomhusundervisning, av regelbunden fysisk aktivitet och/eller naturkontakt.

    Kunskapsöversikten visar att evidensen är tillräckligt stark för att konstatera att utomhusundervisning bidrar positivt både indirekt och direkt till skolprestation och skolresultat. Extremt få studier, endast någon enstaka, kan påvisa ett samband mellan utomhusundervisning och negativa effekter på elevernas lärande, pedagogernas arbetssituation eller på skolverksamheten i stort. Slutsatsen är att det finns tillräcklig stark evidens för att rekommendera mer utomhusundervisning i skolans pedagogiska verksamhet – eftersom inslag av undervisning i kombination med utomhusvistelse genererar en rad positiva effekter på elevers lärande, hälsa, fysiska aktivitet och deras personliga och sociala utveckling. Sammantaget visar översikten:

    • att utomhusundervisning leder till en lång rad positiva effekter för elever i grundskoleålder, till exempel förbättrad inlärning (ökad kognitiv förmåga, koncentration, arbetsminne, och studiemotivation),
    • att evidensen är tillräckligt stark för att det är möjligt att överväga implementering av fler utomhusbaserade inslag i undervisningen bland barn och elever i hela utbildningssystemet,
    • att evidensen är tillräckligt stark för utomhusundervisningens positiva kognitiva effekter, vilket gör det möjligt att överväga en förstärkning av befintliga såväl som inrättande av nya nationella utbildningsinsatser som främjar utomhusundervisning, fysisk aktivitet, samt naturkontakt i grundskolan, till exempel genom att involvera landets lärosäten med lärarutbildning i ett gemensamt utvecklingsarbete på nationell nivå,
    • att utomhusundervisning ligger i linje med moderna pedagogiska modeller för skolutveckling, undervisning och lärande.

    Stöd för ökad måluppfyllelse och god folkhälsa

    Forskningen visar att utomhusundervisning med regelbunden fysisk aktivitet och naturkontakt både direkt och indirekt kan ha positiva och meningsfulla effekter på lärande, skolprestationer, hälsa och välbefinnande, samt på elevernas personliga och sociala utveckling.

    De statistiska effekterna (effektmåtten) ligger vanligtvis på en låg till måttlig nivå. Men på samhällsnivå skulle de potentiellt kunna få stor relevans ur ett folkhälso- och skolperspektiv genom att bidra till högre måluppfyllelse inom grundskola, förskoleklass och fritidshem. Detta under förutsättning att program och kompetenshöjande åtgärder för utomhusundervisning införs i bred skala och är långsiktiga. Forskningen påtalar att tidsmässigt längre och mer omfattande utbildningsprogram eller insatser uppnår större effekter både motoriskt, socialt och kognitivt än korta och sporadiska pedagogiska insatser.

    Stark evidens för faktorer som indirekt påverkar skolprestationer

    Forskningen visar att regelbunden fysisk aktivitet med utökad rörelse och naturkontakt under skoldagen generellt leder till positiva effekter på inlärningsförmåga, skolprestationer och på en lång rad faktorer som är av betydelse för elevers utveckling men också för undervisningen. Betydelsefulla vetenskapliga argument finns för att utomhusundervisning – jämfört med när elever undervisats helt eller till stor del inomhus med mer eller mindre traditionella undervisningsstrategier – främjar faktorer som indirekt påverkar skolprestationer såsom förbättrad koncentration, arbetsminne samt personlig och social utveckling. Forskningen visar att detta i sin tur kan leda till ökad studiemotivation, förbättrad självkänsla, självkontroll och impulskontroll, kreativitet, samarbetsförmåga samt intention till en hälsosammare livsstil (motion och matvanor). Hög grad av fysisk aktivitet, liksom regelbunden naturkontakt under skoldagen och i undervisningen, uppvisar samband med skolprestation och med en lång rad faktorer som indirekt påverkar skolresultaten i positiv riktning hos elever.

    Mer undervisningstid i teoretiska ämnen leder inte till bättre resultat

    Forskningen visar att ökad fysisk aktivitet under skoldagen eller utökad undervisning i Idrott & hälsa inte leder till sämre resultat i teoretiska ämnen. Den mesta forskningen tyder tvärtom på att mer fysisk aktivitet leder till positiva effekter på skolresultat i teoretiska ämnen för elever, även om mer forskning behövs inom området.

    Inte heller en ökning av antalet undervisningstimmar i teoretiska ämnen, på bekostnad av bland annat Idrott & hälsa, leder till bättre resultat i teoretiska ämnen. Flera forskare och systematiska översikter påpekar också att en ökning av inomhusundervisning i teoretiska ämnen till och med kan öka risken för fysisk och psykisk ohälsa hos eleverna.

    Mer longitudinell forskning behövs

    För att öka skolans måluppfyllelse, förbättra skolresultat och främja sunda levnadsvanor bland barn och unga, visar kunskapsöversikten att det finns tillräckligt stark evidens för att överväga systematisk implementering av utomhusbaserad undervisning i skolan. En stor del av forskningsmaterialet består dock av tidsmässigt korta utvärderingar. Detta försvårar delvis möjligheten att dra mer långtgående slutsatser av hur utomhusbaserade inslag i den pedagogiska verksamheten kan bidra till en långsiktig och ändamålsenlig skolutveckling som påverkar skolresultaten i positiv riktning. Således behövs fler longitudinella studier utifrån en svensk skol- och undervisningskontext.

    Kunskapsöversiktens huvudindelning

    Litteraturgenomgången resulterade i att forskningsmaterialet kunde sorteras i tre huvudkategorier. I kunskapsöversikten redogörs för kunskapsläget utifrån var och en av dessa kategorier, nämligen utomhusundervisningens effekter på skolprestation, fysisk aktivitet och naturkontakt.

  • Simonsson, Christian
    Linköping University, Department of Biomedical Engineering, Division of Biomedical Engineering.
    Mathematical modeling of adrenaline-induced adiponectin secretion in white adipocytes2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There is an ongoing worldwide obesity epidemic. As a consequence, prevalence of obesity- related diseases and conditions are rapidly increasing. One of these related conditions is type 2 diabetes (T2D), which alone caused 1.5 million deaths in 2012. Thus, it is of upmost importance to develop a more complete understanding of these interrelated diseases. At the heart of all these diseases lies the adipose tissue. This tissue is a major endocrine organ, and one of the key secreted cytokines is adiponectin. Adiponectin interplays with the complex insulin signaling network, and adiponectin levels are inversely related with increased adiposity. The presence of these complex dependencies argues for the usage of mathematical modelling. In the work of Brännmark et al, a model of short-term adiponectin release has been validated. However, this model did not include adrenergic signaling, which is the canonical pathway for in situ regulation of adiponectin secretion. To fill this gap, herein, a mechanistic model describing adrenaline-induced short-term adiponectin exocytosis in white adipocytes has been constructed. The newly constructed model is capable of describing experimental data depicting adiponectin release due to adrenergic stimulation as well as data for different mediator combinations. By implementing adrenergic receptor components, the transition to a more physiological model has been initiated. By finding the smallest possible model capable of describing data, one can argue that the model depicts, to some degree, the fundamental mechanisms for short-term adiponectin

    secretion. Thus, this work has contributed to solidifying the framework of the mechanisms behind short-term adiponectin secretion from white adipocytes. The result of the model work upholds the role of adrenergic signaling as a central regulatory mechanism for adiponectin release. The constructed model could be used as a fundament for creating a model describing adiponectin release under diabetic conditions.

  • Lillberg, Henrik
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control.
    Johannesson, Martin
    Linköping University, Department of Electrical Engineering, Automatic Control.
    Investigation of Steering Feedback Control Strategies for Steer-by-Wire Concept2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The automotive industry is currently undergoing a paradigm shift. One such example in the next generation steering is the Steer-by-Wire (SbW) technology. SbW comes with a lot of advantages but one of the big challenges is to provide the driver with a realistic steering feel. More precisely, steering feel can be defined as the relationships between the steering wheel torque, the steering wheel angle and the dynamics of the vehicle.

    Accordingly, the first contribution of this work will be to present transfer functions between these quantities that resemble those observed in traditional steering systems. The steering feel/feedback is then achieved by an electric motor which can be controlled by different control strategies. In this thesis three different control strategies are investigated.

    The first straightforward strategy is called open loop since there is no feedback controller in the system. The second strategy is torque feedback control and the third strategy is angle feedback control. All three systems are evaluated in terms of reference tracking, stability, robustness and sensitivity. Here reference tracking is defined as tracking a desired transfer function. The desired transfer function is denoted as the reference generator.

    When fulfilling the requirements the analysis shows that the torque feedback system has a better reference tracking than the other evaluated systems. It is also concluded that the open loop system has a compromised reference tracking compared to the torque and angle feedback systems.

    Since the SbW technology is still an undergoing area of research within the automotive sector this work can be used as a basis for choice of control strategy for steering feedback systems and also as a guideline for future hardware choices.

  • Brandén, Maria
    et al.
    Linköping University, Department of Management and Engineering, The Institute for Analytical Sociology, IAS. Linköping University, Faculty of Arts and Sciences. Department of Sociology, Stockholm University.
    Bygren, Magnus
    Linköping University, Department of Management and Engineering, The Institute for Analytical Sociology, IAS. Linköping University, Faculty of Arts and Sciences. Department of Sociology, Stockholm University / Institute for Futures Studies, Stockholm.
    School Choice and School Segregation: Lessons from Sweden’s School Voucher System2018Report (Other academic)
    Abstract [en]

    The aim of this study is to investigate how school choice opportunities affect school segregation. Theoretically, free school choice may affect school segregation in different directions, depending on its design, baseline residential segregation, and underlying preferences for separation. Our test case is the Swedish voucher-based free school choice system, and we utilize Swedish population register data that include 13 cohorts of ninth graders, with geocoded information on schools, their socioeconomic and ethnic composition, and the composition of the neighborhoods surrounding the schools. To identify causal effects of school choice opportunities, we treat fixed school areas as the unit of analysis, and we follow these over time to net out time-invariant area-level confounders. Within-area panel estimates indicate segregation based on both ethnic and educational background to be strongly affected by school choice opportunities. Increased choice opportunities lead to increased school segregation, to a large extent because of a higher propensity among native children and children with well-educated parents to attend newly established (non-public) independent schools. The segregating impact of school choice opportunities is uniform across school areas with different socioeconomic and ethnic profiles, but school segregation increases much more in residentially integrated areas as a consequence of an increase in school choice options. The lesson to be learned from the Swedish case is that large scale school voucher systems need to be designed to include mechanisms that counteract the strong segregating forces that such systems appear to produce.

  • Wiktander, Jennifer
    et al.
    Linköping University, Department of Behavioural Sciences and Learning, Education and Sociology.
    Edward, Carin
    Linköping University, Department of Behavioural Sciences and Learning, Education and Sociology.
    Jag lyssnar gärna på dig: Fokus på ett relationsorienterad ledarskap vid arbetsmiljöarbete2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study is to study how labour organizations relate to the work environment regulations AFS 2015:4 and AFS 2001:1 and how managers exercise work environment management in practice. To study that we conducted interviews and used a qualitative research method. Today ́s labour market is characterized by complexity, flexibility and more decentralized organizations. It can be a challenge for a manager to orientate in this complexity. Due to the high level of psychological ill health, today ́s focus is increasingly on the social and organizational work environment. Due to Sweden’s highnumbers of employees reporting sick, a sick leave caused by psychological ill health, focus is increasingly pointed towards the social and organizational work environment. The focus of this study is on how the work environment and leadership style can be assumed to promote satisfied employees. The results show that for the relationship-oriented leadership style to have an opportunity to achieve the desired effect on the work environment, empowerment of the employee is required. Organizational structure with a relational focus, such as conversations, dialogue, follow-up and how to carry out necessary precautions and actions are also in focus in this study.

  • Boström, Annelie
    et al.
    Linköping University, Department of Behavioural Sciences and Learning.
    Gustafsson Åhlin, Ingrid
    Linköping University, Department of Behavioural Sciences and Learning.
    Erfarenheter av prevention av psykisk ohälsa och suicid: en kvalitativ studie inom social- och utbildningsförvaltningen2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Studien har som syfte att bidra med kunskap om och förståelse för hur arbetsgivare arbetar med psykisk ohälsa och suicidprevention i arbetslivet (kommunförvaltningar). Vår undersökning är en kvalitativ studie med en hermeneutisk inriktning och en induktiv ansats. Vi valde en semistrukturerad intervjuform då vi genom informanternas egna beskrivningar önskade få fram hur arbetet med psykisk ohälsa och suicid ur ett arbetsgivarperspektiv ser ut och upplevs i praktiken. Resultatet av våra intervjuer visar bland annat att det fortfarande upplevs svårt att prata om psykisk ohälsa och särskilt suicid. Vidare framkom att det är ett större fokus riktat utåt mot klienter och elever, det vill säga förvaltningarnas “kunder”, än inåt mot den egna organisationen och dess medarbetare. Vi fick fram tio olika kategorier, exempelvis tabu/stigma/skam, som ett sätt att beskriva problematiken kring psykisk ohälsa och suicid i samhället.

  • MILIOTIS, GEORGIOS
    Linköping University, Department of Thematic Studies, Department of Child Studies.
    School bullying in contemporary Greece: An empirical examination of school bullying and its prevention in the Greek press2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    School bullying and its prevention have emerged very recently as a crucial topic in the Greek research and media. This thesis uses three bullying cases reported in one of the largest morning newspapers in Greece to analyze the discussions around the definition of bullying and its consequences, causes and solutions. Furthermore, the discussions around the concepts of children and childhood are analyzed and reported. Even though the research in Greece the last five years has taken huge steps forward, it has been only based on a more traditional view on bullying, both in research and the media. This thesis suggests that the new paradigm of new social studies could be a vital analytical view on the studies of bullying and its prevention and could be a very useful alternative to be used by both research and the media. 

  • Gonçalves, Laura
    Linköping University, Department of Thematic Studies, Department of Child Studies.
    Children as passive victims or agentic subjects?: A discourse analysis of child mental health and wellbeing in the World Health Organization (WHO) year reports2018Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Child mental health has been an emerging topic in societal as well as scholar spheres. Mental health is intimately connected with wellbeing and as such their promotion by the World Health Organization(WHO) has allowed for governmental and societal structures to be aware of what is necessary to implement and change in order to achieve better child mental health and wellbeing. Through this thesis, the representations of children and how mental health and well-being are constructed are analysed using Bacchi’s “What’s the problem presented to be” (WPR) method. The aim of this studyis to critically examine how the concepts and representations described above are discursively generated in the annual reports of 2015 and 2016 from the WHO. When analyzing the representations of the child, mental health and wellbeing, two major themes are identified: The vulnerable/agentic child and the best place for a child. The first theme discursively represents children in three forms: Helplessness or victim, passive recipients and agentic.The second theme represents not only children but also their families, the institutions and the institutional staff. Here another three discourses emerge: Connection to the nuclear family discourse,the powerful and harming institutions discourse and the blaming the staff discourse. Regarding the concepts of wellbeing and mental health, the results comprising this thesis suggest that, in the reports,mental health is presented to be a question of who the caregiver is and how resources such as education are distributed. Wellbeing is connected to the presence of the parents with the child avoiding thus institutionalization as well as the children becoming victims of the malpractices of the negligent institutional staff and the possibility of children becoming agents in their own lives. Finally,the seemingly unproblematic aspects of such representations indicate that the arguments about the vulnerable/agentic child and the best place for a child, are not put in context and are about a generalized child that does not fit the specificity of children’s worlds.

  • Wallo, Andreas
    et al.
    Linköping University, Department of Behavioural Sciences and Learning, Education and Sociology. Linköping University, HELIX Competence Centre. Linköping University, Faculty of Arts and Sciences.
    Löfgren-Markör, Lotta
    Linköping University, University Services.
    Forsyth, Heather
    Linköping University, University Services.
    Ledarskap, chefskap och medarbetarskap vid LiU: Erfarenheter från utvecklingsarbetet MedLed2018Report (Other academic)
    Abstract [sv]

    I denna rapport presenteras resultaten av utvecklingsarbetet MedLed. Syftet med MedLed har varit att skapa tydlighet och enkelhet i hur Linköpings universitet (LiU) ser på och hanterar frågor om ledarskap, chefskap och medarbetarskap for att medverka till okad hållbarhet hos chefer/ledare och medarbetare. Upprinnelsen till MedLed ar fyra utmaningar som identifierats av LiU:s ledning, HR-enheten och forskare vid HELIX Competence Centre. Övergripande handlar dessa utmaningar om att mota förändrade krav på chefer, ledare (t.ex. forskningsledare, utbildningsledare, programansvariga, studierektorer) och medarbetare. Fyra målsättningar har guidat arbetet i MedLed:

    • Bidra till en långsiktigt minskad stressnivå och ett okat välbefinnande hos LiU:s anställda.
    • Skapa en tydlig bild av vad som förväntas av chefer, ledare och medarbetare vid LiU.
    • Utveckla ett evidensbaserat och LiU-gemensamt synsätt på ledarskap, chefskap och medarbetarskap som kan användas i utbildning, rekrytering och karriärutveckling.
    • Erbjuda stod till organisationen for bearbetning och reflektion kring det utvecklade synsättet på ledarskap, chefskap och medarbetarskap.

    Som underlag for föreliggande rapport har flera olika typer av data samlats in och analyserats. En litteraturöversikt med inriktning mot att sammanställa teorier och tidigare forskning inom området genomfördes for att skapa en god vetenskaplig förankring. For att hitta verksamheter som har innovativa synsätt på hur chefs-, ledar- och medarbetarskap kan utvecklas och integreras har ”benchlearning” genomförts med 13 externa organisationer. Vidare utgörs en central del i materialet av intervjuer med ledningsrepresentanter, chefer, ledare, medarbetare och HR-specialister inom LiU. Syftet med intervjuerna var att skapa en bild av hur dessa olika kategorier av anställda ser på och pratar om ledarskap, chefskap och medarbetarskap. Vidare har också data samlats in genom en dokumentstudie med syfte att kartlägga i vilka dokument som förväntningar kommuniceras samt att ge förslag på hur dessa skulle kunna renodlas och förenklas.

    Resultaten från benchlearningen visade att det i samtliga studerade organisationer finns en syn på framtida utmaningar for chefer, ledare och medarbetare som matchar dem som identifierats for LiU. Vidare framträdde också bilden av att medarbetarna i högre utsträckning an tidigare ses som ledare i betydelsen att de förväntas ta ansvar både for egna arbetsuppgifter, men också for organisationens i stort. Detta ansvar kommuniceras i flera av organisationerna genom olika typer av värdeord. Nar det galler mer konkreta arbetssätt som kan vara intressanta for LiU kan namnas ett fokus på olika typer av arbetsplatsbaserat lärande som metoder for att generera och sprida kunskaper om behov och utmaningar for ledare, chefer och medarbetare. Vidare förekommer det i organisationerna också ett större fokus på medarbetarnas kompetensutveckling vad galler medarbetarrollen an vad som idag finns på LiU.

    I resultaten av intervjuerna framkom att de identifierade utmaningarna for LiU känns igen av medarbetarna. Vidare framträdde också en mer fördjupad bild av hur utmaningarna kommer till uttryck i det dagliga arbetet. Resultaten visade också att synen på chef- och ledarskap ser olika ut beroende på vilken del av organisationen som tillfrågades, men att det finns viss samsyn vad galler önskvärda beteenden hos chefer och ledare. Gällande medarbetarskapet pekade resultaten på att detta for de flesta ar ett positivt laddat begrepp, men det förekom också mer kritiska utsagor i materialet. Tack vare stor frihet i arbetet ansåg respondenterna att det finns goda möjligheter till ansvarstagande, men har pekade resultaten också på motsättningar mellan tydlighet och flexibilitet, konkurrens och samarbete samt mellan individualism och kollektivism. I intervjuerna framkom också synpunkter på universitetsledningen. Bland annat lyftes att ledningen bor agera transparent och inkluderande, att det behovs uttalade mal for helheten samt att medarbetarens del i relation till mal och visioner bor tydliggöras.

    Utifrån dokumentstudien konstaterades att manga dokument vid LiU ar äldre och i behov av att uppdateras eller tas bort. Vidare gör det stora antal totala dokument, och olikheterna i deras innehall nar det kommer till krav och förväntningar på chefer, ledare och medarbetare vid LiU, att det uppstår en otydlighet. Sammantaget ansågs listorna over vad som förväntades av ledare, chefer och medarbetare vid LiU också innehålla väldigt manga punkter. Vidare visade studien också att det ar oklart hur dokumenthierarkin ser ut, vilken terminologi som ska galla och hur olika begrepp ska definieras. Det framkom också att dokumenten till stor del fokuserar på formell ledning, såsom chefskap eller medarbetarskap. Däremot saknas centrala dokument som tydligt lyfter fram andra positioner vid LiU dar ledarskap ar viktigt, såsom exempelvis forskningsledare.

    I rapportens avslutande kapitel diskuteras studiens resultat. Har argumenterats for att resultaten illustrerar att det inom LiU som organisation inryms flera olika logiker och styrformer som påverkar hur vi ser på chefer, ledare och medarbetare. Den formella linjeorganisationen bestar t.ex. både av byråkrati och management, medan det i mer gränsöverskridande miljöer finns både management och kollegialitet. Det egna vetenskapliga fältet styrs till stor del av de kollegiala idealen. Viss byråkrati återfinns naturligtvis aven har, men ofta kan själva forskningen snarare liknas vid en ”adhokratisk” organisering. Det ar också viktigt att uppmärksamma att de olika logikerna i rummen och styrformerna ibland riskerar att ”krocka” med varandra. En okad grad av medvetenhet om de fyra rummens och styrformernas särdrag och syften kan underlätta for medarbetare att kunna förhålla sig till och hantera olikheterna. Vidare konstateras att detaljerade instruktioner for ledarskap, chefskap och medarbetarskap inte tycks vara möjliga, eller lämpliga att formulera centralt vid LiU, men att det går att urskilja några mer övergripande och förenande punkter som sammanfattar LiU:s syn på ledarskap, chefskap och medarbetarskap.

  • Gustafsson, Fredrik
    et al.
    Linköping University, Department of Electrical Engineering, Computer Vision.
    Linder-Norén, Erik
    Linköping University, Department of Electrical Engineering, Computer Vision.
    Automotive 3D Object Detection Without Target Domain Annotations2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this thesis we study a perception problem in the context of autonomous driving. Specifically, we study the computer vision problem of 3D object detection, in which objects should be detected from various sensor data and their position in the 3D world should be estimated. We also study the application of Generative Adversarial Networks in domain adaptation techniques, aiming to improve the 3D object detection model's ability to transfer between different domains.

    The state-of-the-art Frustum-PointNet architecture for LiDAR-based 3D object detection was implemented and found to closely match its reported performance when trained and evaluated on the KITTI dataset. The architecture was also found to transfer reasonably well from the synthetic SYN dataset to KITTI, and is thus believed to be usable in a semi-automatic 3D bounding box annotation process. The Frustum-PointNet architecture was also extended to explicitly utilize image features, which surprisingly degraded its detection performance. Furthermore, an image-only 3D object detection model was designed and implemented, which was found to compare quite favourably with current state-of-the-art in terms of detection performance.

    Additionally, the PixelDA approach was adopted and successfully applied to the MNIST to MNIST-M domain adaptation problem, which validated the idea that unsupervised domain adaptation using Generative Adversarial Networks can improve the performance of a task network for a dataset lacking ground truth annotations. Surprisingly, the approach did however not significantly improve upon the performance of the image-based 3D object detection models when trained on the SYN dataset and evaluated on KITTI.

  • Kozlov, Vladimir
    et al.
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Nazarov, Sergei A.
    St Petersburg State University, Russia; St. Petersburg State Polytechnical University, St. Petersburg, Russia.
    Zavorokhin, German
    St. Petersburg Department of the Steklov Mathematical Institute, St. Petersburg, Russia.
    Pressure drop matrix for a bifuration of an artery with defects2018Report (Other academic)
    Abstract [en]

    We consider a bifurcation of an artery. The influence of defects of the vessel's wall near the bifurcation point on the pressure drop matrix is analyzed. The elements of this matrix are included in the modified Kirchhoff transmission conditions, which were introduced earlier in [1], [2], and which describe adequately the total pressure loss at the bifurcation point of the flow passed through it.

  • Wedel, Elsa
    Linköping University, Department of Physics, Chemistry and Biology.
    Ecosystem Services as a Pedagogical Perspective for Teaching the Importance of Biodiversity to High School Students2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Reducing the rate at which biodiversity is presently being lost is one of the challenges for the coming years. Through diverse activities, humankind is currently responsible for the extinction of species worldwide, which has consequences for whole ecosystems. The preservation of biodiversity is not only important for its intrinsic values, but also for its role in maintaining the functioning of ecosystems that provide humans with services that are important for our well-being and safety. As it is a concern for all of humanity there is a demand for education that can develop in students an understanding of the complexity which lies behind the ecosystem services of which they benefit. Including how the disturbance of this complexity will lead to consequences for the whole human world. Current attempts to educate the public has failed to conjure motivation and interest. However, ecological network research create opportunity for understanding the underlying relationships between species, and the use of ecosystem services as a pedagogical perspective offers the possibility to demonstrate the importance of these relationships for ecosystem functioning. In this literature review it is examined how this could benefit environmental education in high school.

  • Granath, Klara
    et al.
    Linköping University, Department of Management and Engineering, Economics.
    Kling, Karin
    Linköping University, Department of Management and Engineering, Economics.
    Investigating the Relation Between Microcredit and Female Entrepreneurship in Lao PDR2018Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Even though the idea of microcredit is to stimulate entrepreneurial activities in developing countries, there is an ongoing debate whether this is achieved. Many argue that only providing credit is not enough and see a need for additional components in promoting entrepreneurial activities for the stimulation of economic growth. Moreover, the importance of including women in economic development is widely acknowledged. In Lao People's Democratic Republic where many women run their own businesses and a majority of microcredit borrowers are women, we aimed to examine the relation between microcredit and female entrepreneurship. This was accomplished by conducting semi-structured interviews with 13 Laotian female microcredit borrowers running businesses, as well as interviews with seven representatives from organizations related to microcredit and female entrepreneurship. To understand the female entrepreneurs and the environment in which they operate, we developed a model where factors related to the loan agreement, networking, motivation, gender division of labor and training were identified as important components in the context of Lao PDR. The results support the view that a credit only approach is not enough for the development of female entrepreneurship in Lao PDR.

  • Khodari, Mohammad
    Linköping University, Department of Computer and Information Science, Database and information techniques.
    Decentralized firmware attestation for in-vehicle networks2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Today's vehicles are controlled by several so called electronic control units (ECUs). ECUs can be seen as small computers that work together in order to perform a common task. They control everything from critical tasks such as engine control to less critical functionality such as window control. The most prominent trend that can be observed today is the development of self-driving functionality. Due to inherent complexity of self-driving functionality, ECUs are becoming more dependent on each other. A fundamental problem in today's vehicles is that there does not exist any efficient way of achieving trust in the vehicle's internal-network. How can ECUs be assured that the output of other ECUs can be trusted? If an ECU produces the wrong output when the vehicle is in autonomous mode it can lead to the vehicle performing unsafe actions and risking the lives of the passengers and driver.

    In this thesis we evaluate different already established firmware attestation solutions for achieving trust in a decentralized network. Furthermore, three new firmware attestation solutions specially tailored for the automotive domain are proposed. We demonstrate that all the found existing solutions have a fundamental flaw, they all have a single point of failure. Meaning that if you eliminate the correct node, the entire attestation process stops functioning. Thus, a new more robust solution specially tailored for the automotive domain needed to be developed. Three different consistency verification mechanisms were designed. One parallel solution, one serial solution and one merkle-tree solution. Two of the three proposed solutions, the parallel solution and serial solution, were implemented and assessed. Two tests were conducted, a detection performance test and a timing performance test.

    By assessing the detection performance test and timing performance test of the serial and parallel solutions, it was concluded that the parallel solution showed a significant improvement in both stability and performance over the serial solution.

  • Jönsson, Erik
    Linköping University, Department of Mathematics. Linköping University, Faculty of Science & Engineering.
    Tug-of-war games of the p-Laplacian for analysts2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
  • Sätterqvist, Erik
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Sequences of Functions: Different Notions of Convergence and How They Are Related2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    In this thesis we examine different types of convergence for sequences of functions and how these are related. The functions considered are real valued Lebesgue measurablefunctions defined on a subset of R. We also devote a chapter to explore when continuity of a sequence of functions is preserved under pointwise convergence, and see that this happens precisely when the convergence is quasi uniform.

  • Webb, Grayson
    Linköping University, Department of Mathematics, Computational Mathematics. Linköping University, Faculty of Science & Engineering.
    A Gaussian Mixture Model based Level Set Method for Volume Segmentation in Medical Images2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis proposes a probabilistic level set method to be used in segmentation of tumors with heterogeneous intensities. It models the intensities of the tumor and surrounding tissue using Gaussian mixture models. Through a contour based initialization procedure samples are gathered to be used in expectation maximization of the mixture model parameters. The proposed method is compared against a threshold-based segmentation method using MRI images retrieved from The Cancer Imaging Archive. The cases are manually segmented and an automated testing procedure is used to find optimal parameters for the proposed method and then it is tested against the threshold-based method. Segmentation times, dice coefficients, and volume errors are compared. The evaluation reveals that the proposed method has a comparable mean segmentation time to the threshold-based method, and performs faster in cases where the volume error does not exceed 40%. The mean dice coefficient and volume error are also improved while achieving lower deviation.

  • Andersson, Cristofer
    Linköping University, Department of Behavioural Sciences and Learning, Education, Teaching and Learning.
    Läxor: Att vara eller icke vara2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med denna studie är att uppmärksamma kring hur elever på gymnasienivå uppfattar och förhåller sig till läxor. Studien har genomförts med en kvalitativ metod genom semistrukturerade intervjuer med sju elever, både män och kvinnor, som studerar årskurs ett på en gymnasieskola i mellersta Sverige. Dagens läxforskning, såväl nationellt som internationellt, är till en majoritet inriktad på läxors verkan på studieresultat och lärande. Pickering och Marzano (2007) redogör för att de studier samt rapporter som finns tillgängliga visar motsägelsefulla resultat. Därtill framlägger Warton (2001), vars arbeten om läxforskning är bland de mest förekommande inom ämnet, att dagens forskning saknar studier kring hur elever uppfattar lärares och vuxnas ställningstaganden till läxor, meningen av läxor genomförda av elever samt eventuella utvecklingsskillnader i förståelsen och om dessa påverkas av de olika kontextuella skillnaderna i skolsystemen och typer av läxuppgifter.

    Resultaten i denna studievisar att elevers upplevelser av läxor är associerade obehagskänslor, tidskrav samt en blandning av upplevelsen att läxor är onödiga men passande ibland. Fortsättningsvis visar även resultaten att elever anser att läxor skall ha en noggrann genomgång tillika uppföljning, vara anpassade och intressanta för att de skall upplevas som bra. Slutligen framkommer att elever använder sig av föräldrar, kompisar samt internet, men med olika syften, då de angriper läxor. De slutsatser som går att dra är att läxor spelar en tvetydig roll hos eleverna. Från informanternas utsagor framkommer såväl gehör som kritik för dessa uppgifter. Emellertid finns förklaringar för kritiken och den är inte enbart av att eleverna är aviga till läxa per se, utan att de istället har negativa erfarenheter från att arbeta med läxor. För att uppnå bra erfarenheter erfordras kommunikation tillika interaktion mellan pedagogen och eleverna. Genom att ta del av elevernas föreställningsvärldar, förkunskaper tillika personliga situationer, kan arbetsformer som gynnar samtliga deltagares lärande skapas.

  • Fahlborg, Daniel
    Linköping University, Department of Electrical Engineering, Communication Systems.
    Measuring one-way Packet Delay in a Radio Network2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Radio networks are expanding, becoming more advanced, and pushing the limits of what is possible. Services utilizing the radio networks are also being developed in order to provide new functionality to end-users worldwide. When discussing 5G radio networks, concepts such as driverless vehicles, drones and near zero communication delay are recurrent. However, measures of delay are needed in order to verify that such services can be provided -- and measuring this is an extensive task. Ericsson has developed a platform for simulating a radio environment surrounding a radio base station. Using this simulator, this project involved measuring one-way packet delay in a radio network, and performing a Quality of Service evaluation of a radio network with a number of network applications in concern. Application data corresponding to video streams, or Voice over IP conversations, were simulated and packet delay measurements were used to calculate and evaluate the Quality of Service provided by a radio network. One of the main conclusions of this project was that packet delay variations are asymmetric in uplink, which suggests usage of non-conventional jitter measurement techniques.

  • Andersson, Amanda
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control.
    Näsholm, Elin
    Linköping University, Department of Electrical Engineering, Automatic Control.
    Fast Real-Time MPC for Fighter Aircraft2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The main topic of this thesis is model predictive control (MPC) of an unstable fighter aircraft. When flying it is important to be able to reach, but not exceed the aircraft limitations and to consider the physical boundaries on the control signals. MPC is a method for controlling a system while considering constraints on states and control signals by formulating it as an optimization problem. The drawback with MPC is the computational time needed and because of that, it is primarily developed for systems with a slowly varying dynamics.

    Two different methods are chosen to speed up the process by making simplifications, approximations and exploiting the structure of the problem. The first method is an explicit method, performing most of the calculations offline. By solving the optimization problem for a number of data sets and thereafter training a neural network, it can be treated as a simpler function solved online. The second method is called fast MPC, in this case the entire optimization is done online. It uses Cholesky decomposition, backward-forward substitution and warm start to decrease the complexity and calculation time of the program.

    Both methods perform reference tracking by solving an underdetermined system by minimizing the weighted norm of the control signals. Integral control is also implemented by using a Kalman filter to observe constant disturbances. An implementation was made in MATLAB for a discrete time linear model and in ARES, a simulation tool used at Saab Aeronautics, with a more accurate nonlinear model.

    The result is a neural network function computed in tenth of a millisecond, a time independent of the size of the prediction horizon. The size of the fast MPC problem is however directly affected by the horizon and the computational time will never be as small, but it can be reduced to a couple of milliseconds at the cost of optimality.

  • Berntsson, Simon
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Andreasson, Mattias
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Efficient Route-based Optimal Energy Management for Hybrid Electric Vehicles2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The requirements on fuel consumption and emissions for passenger cars are getting stricter every year. This has forced the vehicle industry to look for ways to improve the performance of the driveline. With the increasing focus on electrification, a common method is to combine an electrical driveline with a conventional driveline that uses a petrol or diesel engine, thus creating a hybrid electric vehicle. To fully be able to utilise the potential of the driveline in such a vehicle, an efficient energy management strategy is needed. This thesis describes the development of an efficient route-based energy management strategy. Three different optimisation strategies are combined, deterministic dynamic programming, equivalent consumption minimisation strategy and convex optimisation, together with segmentation of the input data. The developed strategy shows a decrease in computational time with up to more than one hundred times compared to a benchmark algorithm. When implemented in Volvo's simulation tool, VSim, substantial fuel savings of up to ten percent is shown compared to a charge-depleting charge-sustain strategy.

  • Olofsson, Petter
    et al.
    Linköping University, Department of Management and Engineering, Economics.
    Råholm, Anna
    Linköping University, Department of Management and Engineering, Economics.
    Konkurrensutsättning av lag och ordning: Kan polismyndighetens samhällsekonomiska effektivitet ökas av konkurrensutsättning?2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Uppsatsen undersöker huruvida det är möjligt att konkurrensutsätta polismyndigheten samtom det är samhällsekonomiskt lönsamt. Sedan 1990-talet har det skett mångakonkurrensutsättningar av tidigare lagstadgade marknader i hopp om att skapa bättresamhällsekonomiska förutsättningar. Polismyndigheten valdes ut specifikt för att den verkarpå en marknad som är ett lagstadgat monopol och utmärks av att vara ineffektiv.Eftersom polismyndigheten är en komplex myndighet valde vi att studera två mindre delar avderas verksamhet för att se om en konkurrensutsättning av dessa delar var för sig skulle varagynnsam. De två verksamheter vi valde ut är passmyndigheten och polisens kontaktcenter(PKC). För att kunna dra slutsatser om verksamheterna kategoriseras de antingen som hårdaeller mjuka verksamheter. Hårda verksamheter är vanligtvis de som verkar inomvaruproducerande marknader, mjuka verksamheter är de verksamheter som verkar inomtjänsteproducerande marknader.Tidigare erfarenheter av konkurrensutsättning visar vilka effekter den får i praktiken. För attanalysera den hårda verksamheten passmyndigheten har erfarenheterna från avregleringen avfordonsbesiktningsmarknaden legat till grund. För den mjuka verksamheten PKC användeserfarenheterna från konkurrensutsättningen av äldreomsorgen.Konkurrensutsättning av båda verksamheter visade sig ha god potential för att uppnå en högresamhällsekonomisk effektivitet. Eftersom passmyndigheten är en typisk hård verksamhetskulle det lämpa sig att använda avreglering som konkurrensutsättningsmetod. PKC i sin turär en mjuk verksamhet och därav dras slutsatsen att bästa metod att konkurrensutsätta ärgenom entreprenadmodellen. Detta skulle frigöra resurser som polismyndigheten kan allokeratill verksamheter med större behov.

  • Martinsson, Fredrik
    Linköping University, Department of Management and Engineering, Manufacturing Engineering.
    Development of Robust Automated Handling of pre-impregnated Carbon Fibre2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Prepreg is a fibre reinforced polymer composite material often used by the aeronautical industry. The material supplier has pre-impregnated the fibre often with an epoxy resin and cured it to a semi-viscous B-stage where the material is tacky (adhesive). Manual layup of prepreg components is still common because there are only a few automated layup techniques which has limited geometric capability and high investment cost.

    Swerea SICOMP is a research institute which have in collaboration with partners developed a manufacturing demonstrator for automated layup of carbon fibre prepreg components based on robotic handling. The manufacturing demonstrator is able to; feed out prepreg from a spool onto a cutting table, cut the prepreg into plies, pick the plies from the cutting table and place them on a layup table, consolidate the prepreg plies on the layup table and remove the backing paper that covers one side of the prepreg.

    Three robustness problems has been identified and these forms the bulk of this master’s thesis. The first problem is that the robot is unable to place the plies on the cutting table with sufficient accuracy due to fluctuating position of the prepreg on the cutting table. The second problem is that the end effector used for the pick and place operation sometimes fails to pick the adhesive plies from the cutting table. The problem originates in limited holding force by the end effectors suction cups and limited capability to perform a peeling motion when picking due to the design of the end effector. The third problem is that process variables like temperature is believed to effect the robustness of the demonstrator but has not been further studied.

    The first problem was solved by implementing a probing routine which measures the position of the prepreg on the cutting table with an array sensor mounted to the robot. The measurement values are used to reprogram subsequent operations.

    The second problem seems to be solved by designing and implementing a new pick and place end effector. The new end effector has higher holding force and better capability to perform a peeling motion while picking and placing the tacky prepreg plies. Tests with the new end effector has been promising, the pick and placeoperation performs robustly, but all ply geometries was not tested and some minor adjustment is needed to further improve the placing accuracy.

    The third problem has not been solved but studied. A literature study reviled that temperature, relative humidity and prepreg out of freezer age is likely to effect the prepreg adhesive properties which in turn is known to effect the robustness. A test procedure has been devised to test how these variables effect the robustnessof the demonstrator. The tests should be conducted when all process steps in the demonstrator is up and running.