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  • 1.
    Toivo, Emma
    Linköping University, Department of Management and Engineering.
    Change Management and Supply Chain Management: Employee issues in implementation processes of SCM - The action and re-action related to changes in each stage of an implementation process2008Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [en]

    Competition on today’s market is fierce. Providing a defect-free product is no more a competitive advantage. Now money and focus is put on managing the supply chain, a competitive tool to thriving in today’s business climate. There are two distinct flow pipelines: the order information transfer pipeline and the product transfer pipeline, both dependent on the collaboration efforts of individuals.

    Evolving within supply chain management equals integrating the supply chain from basic to complex; from baseline or functional to internal or external. Bringing focus to where it is found to be lacking, this literary study highlights and connects issues that may arise during implementation of external supply chain integration. The focal point is thus on employee reactions to change, with each stage of implementation that the implementation issues connect to. Simultaneously, the study provides (pre)requisites to management during the different stages, which would support the implemented transition in its different phases.

    The result of this study is a Manger Model that gives an overview of each of the implementation stages, the requisites for management and issues regarding employees at each of the stages. Constructed to be applicable to more than just external integration the model encompasses all the gathered models and theories through a discussion of not only the complexity of the internal and the external supply chain, but also the complex nature of the individuals caught within the implementation, both from the manager’s as well as the employee’s point of view.

  • 2.
    Musimiire, Angela
    et al.
    Linköping University, Department of Management and Engineering, Business Administration.
    Chakhnashvili, Maka
    Linköping University, Department of Management and Engineering, Business Administration.
    Product Adaptation to Different Markets through Technology Innovation2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background and Aim: Markets are getting increasingly complex, competitive and changing. A firm’s ability to respond to environmental challenges is a significant factor for its survival and success. To establish itself in the market, a company needs to adjust the product in a way that meets the expectations and required quality of the target market in other words, make relevant product adaptations. Many aspects of product adaptation have been discussed in the literature ranging from small changes in the product such as specification or design to modifying a company’s market strategy depending on which stage the product is in its life cycle. Technology innovation can enable a firm keep the market share and retain customers especially in a mature and technology driven industry where the market is saturated and consumers diffuse to competitors who easily copy the product. However, the role of technology innovation to adapt a product in the growth stage to mature markets is missing from the present literature. This present thesis will investigate the role of technology innovation in product adaptation and the factors to consider thereof the Swedish high tech company Saab will be used as the case study.

    Methodology: Research method for the present thesis includes the qualitative approach with the case study design. For the purposes of this thesis the Swedish high-tech company Saab will be studied to explore the practices of adapting product (field hospital) to different markets.

    Completion and results: Result of the study showed that there are similarities and differences between what literature provides and Saab does to adapt a product in markets. Analyzing the theory and practice recommendations for Saab were concluded. Suggestions drown for Saab can be useful for other high technology companies as well.

  • 3.
    Zaigham, Mehreen
    et al.
    Department of Obstetrics and Gynecology Skåne University Hospital, Institution of Clinical Sciences, Lund University, Malmö, Sweden.
    Lundberg, Fredrik
    Department of Neonatology, Skåne University Hospital, Institution of Clinical Sciences, Lund University, Malmö, Sweden.
    Hayes, Ronald
    Banyan Biomarkers Inc., Alachua, FL, USA.
    Undén, Johan
    Department of Intensive Care and Perioperative Medicine, Skåne University Hospital, Institution of Clinical Sciences, Lund University, Malmö, Sweden.
    Olofsson, Per
    Department of Obstetrics and Gynecology Skåne University Hospital, Institution of Clinical Sciences, Lund University, Malmö, Sweden.
    Umbilical cord blood concentrations of ubiquitin carboxy-terminal hydrolase L1 (UCH-L1) and glial fibrillary acidic protein (GFAP) in neonates developing hypoxic-ischemic encephalopathy.2015In: The Journal of Maternal-Fetal & Neonatal Medicine, ISSN 1476-7058, E-ISSN 1476-4954, Vol. 29, no 11, 1822-1828 p.Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To compare ubiquitin carboxy-terminal hydrolase L1 (UCH-L1) and glial fibrillary acidic protein (GFAP) concentrations in umbilical cord blood of neonates who develop Sarnat stage II-III hypoxic-ischemic encephalopathy (HIE) to healthy controls, and to relate the concentrations to the severity of neurology and long-time outcomes.

    MATERIAL AND METHODS: Cord sera of 15 neonates with HIE II-III and 31 matched controls were analyzed for UCH-L1 and GFAP. Comparisons were performed for cord artery pH, amplitude-integrated electroencephalography (aEEG), stage of HIE, and death or sequelae up to an age of 6 years. Parametric and non-parametric statistics were used with a two-sided p < 0.05 considered significant.

    RESULTS: Among controls no associations between biomarker concentrations and gestational age, birthweight, length of storage of cord sera and degree of hemolysis were found. No significant differences in biomarker concentrations were found between HIE neonates and controls, and no differences were found with regard to HIE stage, cord acidemia, severity of aEEG changes, or persistent sequelae or death.

    CONCLUSIONS: No differences in cord blood UCH-L1 and GFAP concentrations were found between HIE neonates and controls, and no associations were found between the biomarker concentrations and the severity of disease, or whether the condition developed into a permanent or fatal injury.

  • 4.
    Matras, Omolara
    Linköping University, Department of Management and Engineering. Linköping University, Faculty of Arts and Sciences.
    In pursuit of a perfect system: Balancing usability and security in computer system development2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Our society is dependent on information and the different technologies and artifacts that gives us access to it. However, the technologies we have come to depend on in different aspects of our lives are imperfect and during the past decade, these imperfections have been the target of identity thieves, cyber criminals and malicious persons within and outside the organization. These malicious persons often target networks of organizations such as hospitals, banks and other financial organizations. Access to these networks are often gained by sidestepping security mechanisms of computer-systems connected to the organization’s network.

    Often, the goal of computer-systems security mechanisms is to prevent or detect threats; or recover from an eventual attack. However, despite huge investments in IT-security infrastructure and Information security, over 95% of banks, hospitals and government agencies have at least 10 malicious infections bypass existing security mechanisms and enter their network without being detected. This has resulted in the loss of valuable information and substantial sums of money from banks and other organizations across the globe. From early research in this area, it has been discovered that the reason why security mechanisms fail is because it is often used incorrectly or not used at all.  Specifically, most users find the security mechanisms on their computers too complicated and they would rather not use it. Therefore, previous research have focused on making computer-systems security usable or simplifying security technology so that they are “less complicated” for all types users, instead of designing computers that are both usable and secure. The problem with this traditional approach is that security is treated as an “add-on” to a finished computer-system design.

    This study is an attempt to change the traditional approach by adjusting two phases of a computer-system design model to incorporate the collection of usability as well as security requirements. Guided by the exploratory case study research design, I gained new insights into a situation that has shocked security specialists and organizational actors alike. This study resulted in the creation of a methodology for designing usable and secure computer-systems. Although this method is in its rudimentary stage, it was tested using an online questionnaire. Data from the literature study was sorted using a synthesis matrix; and analyzed using qualitative content analysis. Some prominent design and security models and methodologies discussed in this report include User-Centered System Design (UCSD), Appropriate and Effective Guidance for Information Security (AEGIS) and Octave Allegro. 

  • 5.
    Söllvander, Henrik
    Linköping University, Department of Computer and Information Science, Human-Centered systems. Linköping University, Faculty of Science & Engineering.
    Magical Garden Balloon Game2014Independent thesis Basic level (university diploma), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    In this thesis I will describe the methods used and problems I have faced and attempted to solve during my time developing a math game for younger kids, a game that makes an attempt to teach kids something called number sense. Teaching pre school kids about number sense is something relatively new and the group I have been working with are of the understanding that it’s something that is very likely to be important to prevent children from falling behind in math during the earlier years of school. Number sense basically means the ability to connect symbolic numbers to their meaning interms of sets, amounts and dimensions such as larger-smaller, higher-shorter, more-less, etc. If this proves to be useful then the quality of education will improve as a result of more children being able to keep up with their math from an early stage.

  • 6.
    Fernlund, Eva
    et al.
    Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Paediatrics in Linköping. Lund University, Sweden.
    Schlegel, Todd T.
    Karolinska Institute, Sweden; Karolinska University Hospital, Sweden.
    Platonov, Pyotr G.
    Lund University, Sweden.
    Carlson, Jonas
    Lund University, Sweden.
    Carlsson, Marcus
    Lund University, Sweden.
    Liuba, Petru
    Lund University, Sweden.
    Peripheral microvascular function is altered in young individuals at risk for hypertrophic cardiomyopathy and correlates with myocardial diastolic function2015In: American Journal of Physiology. Heart and Circulatory Physiology, ISSN 0363-6135, E-ISSN 1522-1539, Vol. 308, no 11, H1351-H1358 p.Article in journal (Refereed)
    Abstract [en]

    Hypertrophic cardiomyopathy (HCM) is a major cause of sudden cardiac death in the young. Based on previous reports of functional abnormalities in not only coronary but also peripheral vessels in adults with HCM, we aimed to assess both peripheral vascular and myocardial diastolic function in young individuals with an early stage of HCM and in individuals at risk for HCM. Children, adolescents, and young adults (mean age: 12 yr) with a family history of HCM who either had (HCM group; n = 36) or did not have (HCM-risk group; n = 30) echocardiography-documented left ventricular (LV) hypertrophy as well as healthy matched controls (n = 85) and healthy young athletes (n = 12) were included in the study. All underwent assessment with 12-lead electrocardiography, two-dimensional echocardiography, tissue Doppler imaging and laser Doppler with transdermal iontophoresis of ACh and sodium nitroprusside. LV thickness and mass were increased in HCM and athlete groups compared with control and HCM-risk groups. The mitral E-to-e ratio, measured via tissue Doppler, was increased in HCM (P less than 0.0001) and HCM-risk (P less than 0.01) groups compared with control and athlete groups, as were microvascular responses to ACh (HCM group: P less than 0.045 and HCM- risk group: P less than 0.02). Responses to ACh correlated with the E-to-e ratio (r = 0.5, P = 0.001). Microvascular responses to sodium nitroprusside were similar in all groups (P = 0.2). HCM-causing mutations or its familial history are associated with changes in cardiac diastolic function and peripheral microvascular function even before the onset of myocardial hypertrophy. Tissue Doppler can be used to differentiate HCM from physiological LV hypertrophy in young athletes.

  • 7.
    Hongxing, Li
    et al.
    Department of Clinical Dentistry – Prosthodontics, University of Bergen, Bergen, Norway.
    List, Thomas
    Orofacial pain and Jaw Function, Malmö University, Malmö, Sweden.
    Nilsson, Ing-Marie
    Specialist Center for Oral Rehabilitation, Norrköping, Sweden .
    Johansson, Anders
    Department of Clinical Dentistry – Prosthodontics, University of Bergen, Bergen, Norway.
    Nordrehaug Astrom, Anne
    Department of Clinical Dentistry – Community Dentistry, University of Bergen, Bergen, Norway.
    Validity and reliability of OIDP and OHIP-14: a survey of Chinese high school students2014In: BMC Oral Health, ISSN 1472-6831, Vol. 14, no 158, 1-10 p.Article in journal (Refereed)
    Abstract [en]

    Background: To determine the impact of oral diseases on everyday life, measures of oral quality of life are needed. In complementing traditional disease-based measures, they assess the need for oral care to evaluate oral health care programs and management of treatment. To assess the reliability and validity of the Oral Impact of Daily Performance (OIDP) and the short-form Oral Health Impact Profile (OHIP-14) among high school students in Xian, the capital of Shanxi province, China. Methods: Cross-sectional one-stage stratified random cluster sample using high schools as the primary sampling unit. Students completed self-administered questionnaires at school. The survey included the OHIP-14 and OIDP inventories, translated and culturally adapted for China, and global oral health and socio-behavioral measures. Results: A total of 5,608 students participated in the study, with a 93% response rate (mean age 17.2, SD 0.8, 52% females, 45.3% urban residents). The proportion experiencing at least one impact (at any frequency) during the previous six months was 62.9% for the OHIP-14 and 45.8% for the OIDP. Cronbachs alpha measured internal consistency at 0.85 for OHIP-14 and 0.75 for OIDP while Cohens kappa varied between 0.27 and 0.58 for OHIP-14 items and between 0.23 and 0.65 for OIDP items. Kappa scores for the OHIP-14 and OIDP additive scores were 0.52 and 0.66, respectively. Both measures varied systematically and in the expected direction, with global oral health measures showing criterion validity. The correlation between OIDP and OHIP-14 was r(s) + 0.65. That both measures varied systematically with socio-behavioral factors indicates construct validity. Conclusion: Both the OIDP and OHIP-14 inventories had reasonable reliability and construct validity in relation to subjective global oral health indicators among adolescents attending high schools in China and thus appear to be useful oral health -related quality of life measures in this context. Overall, the OHIP-14 and OIDP performed equally well, although OHIP-14 had superior content validity due to its sensitivity towards less severe impacts.

  • 8.
    Niemi, Denise
    et al.
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Östh, Jennie
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Från e-handel till butik: Hur renodlade e-handelsföretag som adderar fysiska butiker arbetar för att förmedla en enhetlig bild av varumärket2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: Recently, a new trend in multichannel retailing has been growing where pure eretailersare realizing the importance of being available to the customer in several sales channelsand therefore adds a physical store to its existing e-commerce. The new trend is further referredto as Clicks to Bricks. When multiple sales channels operate under the same brand difficultiesmay arise in conveying a consistent image of the brand, which is highlighted in the existingliterature on multi-channel retailing. However, there are no previous studies that examinechallenges in conveying a consistent image of the brand specifically for companies going fromClicks to Bricks. Based on the fact that Clicks to Bricks is a relatively new phenomenon thearea is fairly unexplored in the academic world, which means that further studies are needed toprovide a greater understanding of the phenomenon.

    Purpose: The study aims to provide a greater understanding of the phenomenon Clicks toBricks, by examining the reasons for pure e-tailers to add a physical store as a sales channel andhow they work to convey a consistent brand image.

    Completion: The study has the design of a multiple case study and has been conducted with aqualitative approach. The study's empirical data is collected from interviews with people onnine different companies that have gone from Clicks to Bricks.

    Conclusion: This study observes the fact that companies going from Clicks to Bricks haverecognized the importance of communicating a consistent brand across their sales channels.Companies have, however, started its work towards communicating a consistent image of thebrand at a late stage in the establishment process. The study identifies opportunities forimprovement in terms of conveying a consistent brand when it comes to companies going fromClicks to Bricks.

  • 9.
    Sami, Abdul Wahab
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, The Institute of Technology.
    Area Efficient ADC for Low Frequency Application2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Analog to digital converters (ADCs) are the fundamental building blocks in communication

    systems. The need to design ADCs, which are area and/or power efficient, has been common.

    Various ADC architectures, constrained by resolution capabilities, can be used for this purpose.

    The cyclic algorithmic architecture of ADC with moderate number of bits comes out to be

    probably best choice for the minimum area implementation. In this thesis a cyclic ADC is

    designed using CMOS 65 nm technology. The ADC high-level model is thoroughly explored and

    its functional blocks are modelled to attain the best possible performance. In particular, the

    nonlinearities which affect the cyclic/algorithmic converter are discussed. This ADC has been

    designed for built-in-self-testing (BiST) on a chip. It is only functional during the testing phase,

    so power dissipation is not a constraint while designing it. As it is supposed to be integrated as

    an extra circuitry on a chip, its area really matters.

    The ADC is designed as 10-bit fully differential switch-capacitor (SC) circuit using 65nm

    CMOS process with 1.2V power supply. A two stage Operational Transconductance Amplifier

    (OTA) is used in this design to provide sufficient voltage gain. The first stage is a telescopic

    OTA whereas the second is a common source amplifier. The bottom plate sampling is used to

    minimize the charge injection effect which is present in the switches.

  • 10.
    Yaochuan, Chen
    Linköping University, Department of Electrical Engineering, Computer Engineering. Linköping University, The Institute of Technology.
    Binary Instruction Format Specification for NoGap2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Nowadays, hardware designers want to get a powerful and friendly tool to speedup the design flow and design quality. The new development suit NoGap is pro-posed to meet those requirements. NoGap is a design automation tool for ASIP,it helps users to focus on the design stage, free them from module connection andsignal assignment, or integration. Different from the normal ADL tools which limitusers’ design ideas to some template frameworks, NoGap allow designers to im-plement what they want with NoGap Common Language (NoGapCL). However,NoGap is still not perfect, some important functionalities are lacking, but withthe flexible generator component structure, NoGap and NoGapCL can easily beextended.This thesis will firstly investigate the structure of Novel Generator of Acceler-ators and Processors (NoGap) from software prospective view, and then present anew NoGap generator, OpCode Assignment Generator (OpAssignGen), which al-lows users to assign operation code values, exclude operation codes and customizethe operation code size or instruction size.A simple example based on the Microprocessor without Interlocked PipelineStages (MIPS) instructions sets will be mentioned to give users a brief view ofhow to use OpAssignGen. After that, the implementation of the new generatorwill be explained in detail.What’s more, some of NoGap’s flaws will be exposed, but more suggestionsand improvements for NoGap will be given.At last, a successful synthesis result based on the simple MIPS hardware im-plementation will be shown to prove the new generator is well implemented. Moreresults and the final conclusion will be given at the end of the thesis.

  • 11.
    Sand, Victor
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Dynamic Visualization of Space Weather Simulation Data2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The work described in this thesis is part of the Open Space project, a collaboration between Linköping University, NASA and the American Museum of Natural History. The long-term goal of Open Space is a multi-purpose, open-source scientific visualization software. The thesis covers the research and implementation of a pipeline for preparing and rendering volumetric data. The developed pipeline consists of three stages: A data formatting stage which takes data from various sources and prepares it for the rest of the pipeline, a pre-processing stage which builds a tree structure of of the raw data, and finally an interactive rendering stage which draws a volume using ray-casting. The pipeline is a fully working proof-of-concept for future development of Open Space, and can be used as-is to render space weather data using a combination of suitable data structures and an efficient data transfer pipeline. Many concepts and ideas from this work can be utilized in the larger-scale software project.

  • 12.
    Nilsson, Jonathan
    Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Arts and Sciences.
    Self-assessed resilience within municipal governments: Creating a self-assessment tool to measure resilience in municipal governments in Sweden.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Resilience engineering has been used in safety research and development within the aviation and nuclear domain for several years but within crisis management for municipal governments in Sweden it is not commonly applied. Therefore there is little to no knowledge about and competency in resilience engineering within the municipal governments in Sweden. The crisis management system in Sweden put almost all responsibility in an event of crisis on the municipal government in which municipal the crisis occurs. This puts a lot of pressure on relatively small and limited organizations and in an effort to relieve some pressure from these organizations resilience engineering can be used as a method to evaluate and further develop safer and more robust organizations which in turn creates a safer crisis management system in Sweden. To quickly spread the use of resilience engineering among municipal governments, or even a limited amount of it, in an easy way this study attempted to create a self-assessment tool for the municipal governments. The self-assessment tool was developed with the RAG in mind and also drawing inspiration from the NASA TLX. The self-assessment tool was created as a survey and went through a two-stage pilot test before being used. In an attempt to validate the self-assessment survey a traditional RAG was conducted in the form of an interview study. The study used an in between group design, were one group were given the self-assessment survey and another group was interviewed in a semi-structured manner. The data collected were evaluated and compared. The results of this study indicated that with further development the self-assessment survey could be used for practical purposes and the greatest contribution of this study is a new method for measuring resilience using self-assessment.

  • 13.
    Haglund, Emelie
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, The Institute of Technology.
    Systematisk bedömning av våtmarksväxter som substrat för biogasproduktion2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Two environmental problems today are the increased concentrations of greenhouse gases in the atmosphere and eutrophication.  Therefore, two challenges are reducing greenhouse gas emissions and fluxes of nutrients. Another challenge is to secure the energy supply in a world where energy demand is increasing. New renewable energy sources need to be developed both to secure the energy supply, but also to reduce the use of fossil energy. A renewable energy source is biogas that can be used for electricity, heating and as vehicle fuel. It is predicted that substrate for biogas production will be a limitation in the future, therefore, new substrate need to be evaluated. Wetland plants are an alternative substrate for biogas production and evaluated in this study.  Wetlands and it is plants are interesting to study because they can reduce the concentration of nutrients and therefore help to reduce the problem of eutrophication.  The study was performed within a project at Biogas Research Center and was a literature study with the study of a case. The method used has been developed in the project and is a Multi Criteria Assessment (MCA), which means that there are several different areas being studied. Areas taking into account the biological, economic, chemical, environmental and technological aspects. In order to structure the data, a matrix consisting of the different key areas was used. To clarify the opportunities and obstacles a semi-qualitative assessment was done for each key area. The case studied was a wetland in an agricultural landscape. The wetland is 5 ha and was constructed a few years ago to work as nitrogen and phosphorous trap. There is no vegetation in the wetland because it is relatively new. The plants that were studied during the study was therefore plants that are potential to grow in the wetland in the future. The studied plants were reed, reed canary grass and cattail. In the wetland it is possible to regulate the water and thereby drain the water to facilitate harvesting.   The results showed that the technology available today for the harvesting and chopping needs to be developed because it does not meet the required standards. There are various techniques for digestion, but since the dry matter is high for the plants dry fermentation is preferable, or a two-stage system in which the first step is dry digestion. A wetland provides a relatively small amount of biomass and therefore it is better to co-digest the plants on a farm biogas plant.  Wetland plants are not approved substrates for certification of bio fertilizer, which can be an obstacle. The bio fertilizer also has a low value because the plants contain low levels of nutrients.Wetlands reduce the amount of nutrients and harvest of wetland plants contributes to the retention of phosphorus increases. Wetlands emit methane and nitrous oxide that affect global warming.Today, there is no economic viability of harvesting wetlands. A system in which compensation is obtained for the environmental benefit that harvest provides is an option to increase profitability.

  • 14.
    Tuvhag, Ellinor
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Undersökning av koppars effekt som antibakteriellt agens i tyg2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study was to test the antibacterial effect of thin copper treads woven into a polyester fabric. The investigation was done by inoculation of Staphylococcus aureus strain ATCC 6538 to the fabric and evaluation of the number of viable cells post exposure by viable count. The issue to be answered was whether the copper fabric had a bactericide or bacteriostatic effect? The fabric is still in prototype stage, and if proven to have antibacterial properties the aim is to use it to prevent bacterial growth in wounds and other vulnerable locations in clinical care. Copper is an essential trace element, but also has antimicrobial properties through a wide range of mechanisms where cell membrane damage is one of the more important. Methods used for inoculation was the absorption method, where a nutrient broth containing S. aureus was pipetted on to the fabric specimens, and the transfer method where the fabric specimens were pressed onto an agar plate that had previously been spread with peptone salt solution containing S. aureus. Total number of bacteria per fabric specimen after short contact (<1 min) and incubation (18-24 h at 37±2°C) was calculated. Incubation showed significant difference in total number of bacteria between the copper fabric and negative control in three of four tests. Short contact showed a tendency of antibacterial effect. The conclusion was that the copper fabric harmed and killed bacteria during incubation but that more records would be needed to be sure about the effects of short contact on bacteria.

  • 15.
    Munisamy, Manokar
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    A Template-Based Java Code Generator for OpenModelica and MetaModelica2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The current OpenModelica Complier (OMC) translates Modelica models into executable Ccodethrough several stages. The Code Generator is the final stage of the compiler whichgenerates target C-code from the optimized sorted equations. Recently, the Code Generator inOMC has been rewritten using the OpenModelica text template language. This gives a moreconcise and easier to understand code generator. Modeling and simulation is becomingincreasingly used in several application areas. There is demand for the OpenModelicaComplier (OMC) to generate code in languages like C#, CSharp, XML, JAVA and so on. Inthis thesis work, we implement a Java code generator to translate the internal equation-basedmodels in OpenModelica and its extension MetaModelica into a Java code representation. Tocreate the Java code generator we used the OpenModelica text template language, also calledSusan. This work is an important step on the way to finalize a full version of a Java CodeGenerator for the OpenModelica Complier (OMC).

  • 16.
    Ahlsén, Carl
    et al.
    Linköping University, The Tema Institute. Linköping University, Faculty of Arts and Sciences.
    Felczak, Michael
    Linköping University, The Tema Institute. Linköping University, Faculty of Arts and Sciences.
    Hinder & möjligheter med dagvattenhantering: Fallstudier över Linköping och Norrköping kommuns arbete med alternativ dagvattenhantering2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    More frequent and intensified rainfalls are expected to occur due to climate change in the nearfuture. This together with a higher proportion of paved areas increases the pressure on today’sstorm water systems (Risinger, 2014; Boverket, 2013; Stahre, 2006). Traditional storm watersystems (i.e. underground pipe systems) have during last decades started to be questioned(Olshammar & Baresel, 2012). The precipitation over Sweden is expected to increase 10-20% over the next century (SMHI, 2009). Increased precipitation may cause temporary capacityloss in pipe-based storm water system with flooding in sensitive areas as a result (Östlund &Lagerblad, 2011). To decrease the potential stress on traditional storm water systems,sustainable urban drainage systems have started to be developed (Viklander & Bäckström,2008). The era of traditional storm water systems has reached a breaking point and moresustainable storm water systems has become more desired as a complement to today’ssystems (Cettner et al, 2014; Semadeni-Davies et al., 2007). In order to build an increaseunderstanding sustainable storm water management it is decisive to investigate what obstaclesthat municipalities has to tackle, regarding storm water management. This study aims toanalyze problems that may occur concerning storm water management including whatchallenges and possibilities that municipalities have to face. The study is based on qualitativeinterviews with informants in the municipalities of Linköping and Norrköping to see how theyare working with storm water and sustainable storm water management. The conclusions ofthe study is mainly, the need for a more pronounced governance, a more explicit demandconcerning laws and regulations, in particular the Swedish planning and building act, acommon vision about how storm water management practices should be handled and finallyquestions concerning how storm water should be handled in an early stage in the planningprocess. This is the main factors to facilitate the work with sustainable urban drainage system.

  • 17.
    Mihaylov, Veselin
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, The Institute of Technology.
    Comparative life cycle impact assessment of a battery electric and a conventional powertrains for a passenger transport ferryboat: A case study of the entire integrated system for vessel propulsion2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis represents a life cycle impact assessment of a state of the art electrically driven power train. It is expected to be installed in a diesel engine passenger ferry boat, currently transporting passengers in downtown Stockholm archipelago. The assessment has a comparative character in between the currently operating and the new power train in order to differentiate and recognize which of the two propulsion options is the environmentally preferable choice.

    The scope of the study is directed towards the thorough examination of both power trains so that it can represent most closely the two specific technological cases. Studied and assessed were the three main life cycle phases of each power train – raw materials acquisition and manufacturing, use phase and end of life phase. The fundament of the study involved creating environmental models for each and every component of the drive trains, the propulsion fuel and energy used, and the services related to waste treatment in the last phase of their functional life. The environmental models were later used to build live cycle inventories that served to derive the respectful impact from the item analyzed. The data used to model the battery electric power train was provided directly from the manufacturer, where the end of life procedures carried out were assumed where possible. The main battery pack for the electric power train was not modeled in terms of  end of life procedures due to insufficiency of information. Almost no generic information was available to model the diesel engine and it was calculated by creating auxiliary simplified cad models. The rest of the data required to achieve an environmental inventory regarding the power train was available from a subcontractor. Both studied options were modeled with allocation approach that includes the avoided production of materials at the waste treatment stage where there was sufficient information to do that. There was none to model the main battery packs avoided production which is a major component of the battery electric system. To model the use phase of the diesel engine power train, research data regarding combustion emissions and waterborne emissions was utilized. A number of electricity mix models were applied to create a sensitivity analysis of the operation phase of the battery electric power train. Chosen for baseline scenarios simulating the use phases of both power trains are use of Nordel market electricity mix and the combustion of low sulfur diesel with five volumetric percent rape methyl ester additive.

    For the purposes of the assessment eighteen midpoint impact indicators were used to cover the areas of global warming potential, human health and quality of eco systems. The results from the study show that the estimated impact from both power trains is small enough to have almost no influence on the results from the two baseline scenarios. Based on this it was concluded that for future research of similar cases either generic information can be used or a cut-off can be applied. After the assessment, more environmentally favorable was estimated the diesel engine power train because of the large burdens from the battery manufacturing in the battery electric option. Further assessment determined that the diesel engine power train again is less environmentally intensive than the battery electric with the main battery burdens excluded. In the overall life cycle impact assessment both power train showed different results in the different impact categories, which could not place a definitive propulsion option of choice. The conclusions from the analysis are that the diesel engine power train causes higher impact in the categories related to global warming, fossil depletion and in most ecosystems quality indicators. The battery electric version in its base line scenario, on the other hand, expresses higher impact in categories related to human health and in the remaining eco system quality midpoint-scores.

  • 18.
    Bengtsson, Mikael
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    A clock driver with reduced EMI2014Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A clock driver that works on the principle of charging and discharging the clock network in a VLSI circuit in two steps is investigated in a few different configurations. The aim of the design is twofold:

    • to reduce the power consumption
    • to reduce the third harmonic of the clock signal, and thereby the EMI (electromagnetic interference) emitted by the clock network.

    The first should be possible to accomplish as the clock interconnect network gets charged by half the voltage during each rising transition, and the second should be possible to accomplish by carefully time the rising and falling transitions, so that the third Fourier coefficient of the resulting wave form cancels.

    The drivers are loaded by eight 16-bit adders. The drivers’ power consumption, and the spectrum of the output signal, are investigated under varying clock frequencies, power supply voltage, and driver architecture. The results are compared to a conventional square wave clock.

    The results are that while the third harmonics of the resulting output sees an improvement in all the investigated cases over the square wave clock, the power savings are, for higher clock frequencies, more than completely canceled by the extra power needed in the logic stage which controls these drivers. On the other hand, the power consumption of the new driver appears to drop below that of the conventional driver when the clock frequency drops below approximately 100MHz.

    A few suggestions for further investigations of new designs and clock wave forms are given.

  • 19.
    LeMoine, Pierre
    Linköping University, Department of Electrical Engineering. Linköping University, The Institute of Technology.
    Large Scale Generation of Voxelized Terrain2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Computer-aided generation of virtual worlds is vital in modern content production. To manuallycreate all the details which todays computers can visualize would be too daunting atask for any number of artists. Procedural algorithms can quickly generate content, but thecontent suffers from being repetitive. Simulation of geological processes produce good resultsbut require a lot of resources.

    In this report a solution is presented which combines procedural algorithms with geologicalsimulation in the form of erosion. A pre-processing stage generates a heightfield using proceduralnoise which is then eroded. The erosion is accelerated by being performed on the GPU.A road network is generated by connecting points scattered in the world. The pre-processedworld is then used to define a field function. The function is sampled in a grid as neededto produce voxels with different materials. Roads are added to the world by changing thematerial of the voxels. The voxels are then rendered as textured tiles depending on material.

    The generated worlds are varied and interesting, much more so than worlds created purelyby procedural methods. A world can be pre-processed within a few minutes and explored inrealtime.

  • 20.
    Pishali Bajestani, Behnam
    Linköping University, Department of Culture and Communication, Language and Culture. Linköping University, Faculty of Arts and Sciences.
    A Study of Menace, Pause and Silence in Harold Pinter’s Early Plays2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The particular characteristics of Pinter’s theatre such as the theme of violence, the competitive interpersonal relationships, the implied unwillingness in communication between the characters and the distinctive use of silences and pauses, distinguish his work from the writers of the absurd. Pinter makes particular use of “Silences” and “Pauses” as theatrical techniques that present a non-verbal way of communication in his plays. The frequent use of these particular techniques in Pinter’s dialogue has urged some critics to coin new expressions such as “Pinteresque” or “Pinter Pause” in the vocabulary of drama to specify Pinter’s technique. One of the important objectives in this essay is to point out the fundamental significance and function of the “Silences” and “Pauses” in Pinter’s work and point out their distinction. I will discuss how the silences and pauses function in Pinter’s theatre as a non-verbal way of communication by creating fragments in the dialogue.

     

    The plays which will be analyzed in this essay are: The Room, The Dumb Waiter, The Birthday Party and The Caretaker. My objective in this essay is to explore the context of these plays with regards to the theme of menace. In the first chapter, I mainly aim to explore the menacing context of these plays regarding the structure of menace and the ways it takes place in each play separately. This analysis will be presented in relation to the spatial territory in which the characters are confined. My aim is also to describe why menace is presented in a theatrical sense. I have chosen to quote some significant passages of each play in each section to illustrate my purposes in the first chapter. The aim of the second chapter is to define the character types involved in the presentation of menace, “The Intruders” and “The Victims”, and to analyze the strategies their use in encounters with each other. After describing the character types I will explore in detail how “The Intruders” use linguistic strategies to confuse and subdue their victims and finally victimize them and how “The Victims” use strategies to cope with menace in order to survive. There are some passages quoted from the plays to facilitate the purpose of the second chapter. The objective in the third chapter is to define “Silences” and “Pauses” as theatrical techniques used in form of non-verbal communication between the characters. I will discuss, based on Peter Hall’s definition, how these techniques are significant in understanding a Pinter play for the readers and the actors who perform them on stage, and will further explore the function of “Silences” and “Pauses” and their distinction in the context of the plays in question in this essay.

     

  • 21.
    Erni, Jonas
    et al.
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Smedberg, Kåre
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    2011 års uppdatering av Skuldsaneringslagen (2006:548): En granskning av hur uppdateringen påverkat enskilda näringsidkare och borgenärer2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background

    The Government considered despite the introduction of the 1994 debt rescheduling act (1994:334) that a solution was needed to the problem that individual traders neither could be granted debt relief or corporate restructuring to thus be able to continue operations if they got into financial insolvency. Therefore in 2007 a special investigator was added to investigate and make proposals for debt relief for individual traders. This study was the basis for the Government bill that the Parliament in October 2010 decided upon.

    The main issue

    What impact has the new debt rescheduling act meant for traders as well as creditors?

    Purpose

    Our purpose of the bachelor thesis is to explore if the new debt rescheduling act (2006:548) has achieved the expected goals, the study will also investigate if the new debt rescheduling act has resulted in any other effects.

    Method

    The study's purpose is answered by a personal interview and several questionnaires that have been collected for the empirical material. The processing of the empirical material was made by a qualitative method. Referrals and propositions have also been used to help answer the bachelor thesis purpose, when the reference frame and the conclusion were set against each other.

    Conclusion

    The actual impact of the new debt rescheduling act (2006:548) is that individual traders can get debt relief if the insolvency was because the trader could not work for a long period of time and therefore ended up in financial trouble. In an insolvency situation the age of the debts are not considered in the same way as before, which meant that a debtor can apply for debt relief in an earlier stage. That this would contribute to deterioration in payment behavior and elevated interest rates appears unchanged. At the change of a criterion such as the age of the debt, a clear effect on the number of debt applications can be seen.

  • 22.
    Daréus, Emma
    et al.
    Linköping University, Department of Computer and Information Science, Statistics. Linköping University, The Institute of Technology.
    Suhr, Hektor
    Linköping University, Department of Computer and Information Science, Statistics. Linköping University, The Institute of Technology.
    En undersökning av sambandet mellan kronisk inflammation och lungcancer2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Cancer is a big health problem in Sweden and one of the leading causesof death. As of recently there has been an increase in the interest in thecancer research community in how chronic inflammation influences theemergence of cancer tumors. In this paper we intend to investigate therelationship between markers of chronic inflammation and lung cancer.We will also look in to the possibility that sialic acid may be a marker oflung cancer.Lung cancer is one of the most common types of cancers in Sweden andhas a high mortality rate compared to other cancers. Reasons for thisbeing both from the fact that it is usually discovered at a later stage and islocated in a sensitive organ make it harder to treat.To do this we will use sialic acid as a marker of inflammation from acohort study done during the early sixties, it will be cross referenced withthe Swedish Cancer Registry from Socialstyrelsen. BMI and age will alsobe used as variables of interest.The method for the paper will use Cox Proportional Hazard Model toestimate the risk of sialic acid relating to the emergence of lung cancer.Sensitivity analysis will be used to consider the effects of smoking as aconfounder variable.The results show that there are reasons to believe that chronicinflammation may have a role in the emergence of lung cancer tumors.There is no evidence in this study that suggest that sialic acid is a goodmarker for an individual having lung cancer. Furthermore, BMI seems tohave a protective effect against lung cancer, but this would need furtherstudy to draw any real conclusions from.

  • 23.
    Li, Qian
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Correlation between Simulation and Measurement of Microwave Resonator Power Handling2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In modern mobile wireless communication, Base Stations (BS) are the most important equipment to build up the mobile network. One of the key elements in BS is the RF filter, which plays a key role to secure the coverage and reliability of the BS. Especially, at Transmitter (Tx) side, the filter must have a high capability to handle the power sent from Power Amplifier (PA) to antenna in any circumstances to ensure the coverage demand. Otherwise, the breakdown will be encountered, setting the power flow in the BS system in an abnormal manner that, finally can lead to the shut down of BS or destroy the system permanently. In this project, three methods using two simulation tools to predict the power handling capability of the RF/microwave resonator which is the elementary component in the BS’s filter are proposed. Power handling tests of selected configurations corresponding to the simulations are implemented as well. In the next stage, the results from the prediction and measurement are compared. Finally, the conclusions of correlation between the prediction and measurement of microwave resonator power handling will be derived.

  • 24.
    Schminder, Jörg Paul Wilhelm
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Feasibility study of different methods for the use in aircraft conceptual design2012Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    The comparison of aerodynamic characteristics for a combat aircraft studywas addressed in this work. The thesis is a feasibility study which reviewsthe workload and output quality efficiency of different numerical and experimentalmethods often used during conceptual aircraft design.For this reason the Vortex Lattice Method (VLM), Euler or Reynolds-Averaged-Navier-Stokes (RANS) simulations were compared to the moreheavier Large Eddy Simulation (LES) which also has the capability to capturealso more complex flow physics, such as those that occur, for example,at high angles of attack. To be able to crosscheck the numerical results,the same static alpha sweep tests were executed in a tunnel. Thereby itwas discovered that it was quite challenging to reach the same values in thewater tunnel as those previously calculated in computational fluid dynamics(CFD) due to different technical issues.However it could be shown that LES simulations can be today a suitabletool for conceptual aircraft design, as they offer much higher levels ofaccuracy and give the designer the possibility to check the new study at anearly stage along the border of the aircraft’s flight envelope.

  • 25.
    Österberg, Frida
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    The visual impact of lamination2005Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This scientific study concerns the visual colour effect caused by the thin polyethylene coating extruded on printed packaging material. The origin of the phenomenon is discovered and characterised mathematically. CIE delta E 2000 theory is adapted in the research for mathematical judgement of visual difference. The report handles the procedure of defining the character of the visual distortion and a characterisation of the effect. In this process it discusses areas as dot gain, colour shift and production parameters. It as well covers the background of colour and printing science. The aim of the work is to create a model that predicts the visual effect of lamination in the proofing stage of the production.

  • 26.
    Lång, Anna-Maria
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Transport- och Trafikeffekter av Samdistribution i Linköping city2005Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Along with the growth of cities and towns around the world, our focus on enviromental problems increases, and so do the demands on a functional distribution system for all kinds of goods. One way of meeting these demands is to coordinate the distribution of goods, a method that has been tested and evaluated in different national as well as international projects. In the national project SAMLIC (coordinated distribution of goods in Linköping City), similar aspects have been discussed, but with the focus being on creating an economically and logistically efficient distribution system for all parts involved. The effects of such a focus are particulary positive since improved enviroment as well as improved service are acheived.

    One important aspect of the SAMLIC-project, is that the initative was taken by the industry in the year 2000. It was motivated by the realization that the great amount of transport in and out of the centre of Linköping resulted in crowding, which proved very costly. The reason for crowding was that the numbers of loading zones were too few in relation to the number of distributors and companies in the City. These problems increased as the City expanded and it was inevitable that something had to be done in order to improve the situation.

    Participants of the SAMLIC-project are the network for conveyors within Linköping City, “Svensk Biogas”, the working-team Inner City Transports, The Group for City-Cooperation, the University of Linköping and the Swedish National Road and Transport Research Institute (VTI), which since spring 2003 is pursuing the project. A PILOT-project was undertaken during spring 2004 within the framework of the SAMLIC-project. The purpose of the PILOTproject was to gather data forming a foundation for the design of an economically and logistically efficent system of distribution. The purpose of the present study was to establish what effects different changes of the present distribution system would give rise to on transport and traffic. Thus, the effects of codistribution on transport were studied by means of statistical modelling, while the traffic simulation program CONTRAM was used to investigate the effects of codistribution on traffic, a program not yet used in this context, to our knowledge.

    The results of the statistical modelling showed that codistribution may reduce the total driving-time by 14 % in average. The statistics also indicated that the average weekly time reduction may be approximately 26 %. The results further reveal that codistribution would reduce the number of stops, which would result in an increased number of custumors per stop.

    The average reduction of the number of stops per week was estimated to approximatly 30 %. The results of the traffic simulations were analyzed by comparing ordinary distribution procedures with distribution according to PILOT- or SAMLIC- distribution and revealed that codistribution as compared to ordinary distribution resulted in positive as well as negative changes of traffic flow. In some parts of the road the flow increased while in other places it decreased. The important point, however, is that the reduction of truck-flow occurred primarily in the most central parts of the City, whichled to a reduction of exhaustemissions.

    This study suggests that different effects on traffic may be induced by codistribution and reveals in which areas these effects would be likely to occur. In terms of the effect of codistribution on queueing, speed differences and time consumption, this study failed to establish any difference between the two distribution procedures compared. This may be due to a lack of a sufficiently sofisticated analyzing technique. It may, however, be possible to produce a more detailed analysis of possible differences between the distribution procedures by using a micro-simulaion tool. Still, the results of the present study suggest that codistribution would improve the present transport situation in several ways.

    The SAMLIC-project is an ongoing project which at present is at a stage when decisions are to be made about matters such as responsibility assignment, criteria of specification, insurance matters and the allocation of different benefits. Not until these and similar further problems are solved will it be possible to initiate a long term system of codistribution.

  • 27.
    Ståhl, Magnus
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Ultra-Wideband Power Amplifier Design2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Power Amplifiers (PA) are large-signal amplifiers. This means that a large part of the load-line is used during signal operation. PAs are normally used as the last stage of communication electronics to provide large enough signals to be transmitted.

    This thesis describes the design of an ultra-wideband power amplifier. As the first part of this thesis, the power amplifier design is presented. In the second part of the thesis a printed circuit board (PCB) was designed and together with the designed circuit tested. The amplifier was designed to have an output of 5 W delivered at the frequency band from 500 MHz to 1 GHz with a gain of 15 dB.

  • 28.
    Lindberg, Markus
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Handling of rock- and soil masses at construction projects2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes how the handling of excavation residues is conducted in Stockholm. The report is the result of a thesis that is done during 2010 at Linköpings Universitet, in conjunction with NCC Construction Sverige. The report aims to see how NCC works with the masses that arise in production. The report focuses on how excavation residues is handled in Stockholm and in two construction projects that NCC conducts in Stockholm, “Citybanan” and the expansion of “Henriksdals sewage treatment plant”. The report makes a comparison between the two projects where the differences and similarities are described. The report is based on fact finding and also interviewing and consulting with people familiar with the subject.

    In major construction projects are often large quantities of excavation masses. The masses can be either soil or crushed rock. To handle these loads in an efficient manner is important in many aspects. To have an effective management of excavation residues is an important part of the stage to get an efficient build process.

    Construction of “Citybanan” and the expansion of “Henriksdals sewage treatment plant” are two projects in which the handling of loads plays an important role. Both projects are conducted in an urban environment where the free space around the workplace is very limited.

    The work has shown that NCC has good procedures for mass handling and in both the investigated projects the mass handling proceeded without major problems. Another conclusion is that the recycling rate of materials has increased in recent years.

  • 29.
    Johansson, Erik
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Wood defect detection using image analysis on laser scatter data2010Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The wood industry constantly demands more and more from their suppliers. As long as there is more money to make the saw mills will be interested in new technology achieving this. To spot defects in an early stage of the saw line and affect the end result is something that is highly wanted from the market.

    This thesis examines the possibility to develop an add-on to an existing construction. This add-on would then detect knots on the block in an early stage with the help of scatter data. A demo application was developed to present the result. The application returns the original image with measured defects and has 95% accuracy.

  • 30.
    Korishe, Abdulah
    Linköping University, Department of Electrical Engineering, Electronics System.
    A Driver Circuit for Body-Coupled Communication2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The main concept of Body-Coupled Communication (BCC) is to transmit the electrical information through the human body as a communication medium by means of capacitive coupling. Nowadays the current research of wireless body area network are expanding more with the new ideas and topologies for better result in respect to the low power and area, security, reliability and sensitivity since it is first introduced by the Zimmerman in 1995. In contrast with the other existing wireless communication technology such as WiFi, Bluetooth and Zigbee, the BCC is going to increase the number of applications as well as solves the problem with the cell based communication system depending upon the frequency allocation. In addition, this promising technology has been standardized by a task group named IEEE 802.15.6 addressing a reliable and feasible system for low power in-body and on-body nodes that serves a variety of medical and non medical applications.

    The entire BAN project is divided into three major parts consisting of application layer, digital baseband and analog front end (AFE) transceiver. In the thesis work a strong driver circuit for BCC is implemented as an analog front end transmitter (Tx). The primary purpose of the study is to transmit a strong signal as the signal is attenuated by the body around 60 dB. The Driver circuit is cascaded of two single-stage inverter and an identical inverter with drain resistor. The entire driver circuit is designed with ST65 nm CMOS technology with 1.2 V supply operated at 10 MHz frequency, has a driving capability of 6 mA which is the basic requirement. The performance of the transmitter is compared with the other architecture by integrating different analysis such as corner analysis, noise analysis and eye diagram. The cycle to cycle jitter is 0.87% which is well below to the maximum point and the power supply rejection ratio (PSRR) is 65 dB indicates the good emission of supply noise. In addition, the transmitter does not require a filter to emit the noise because the body acts like a low pass filter.

    In conclusion the findings of the thesis work is quite healthy compared to the previous work. Finally, there is some point to improve for the driver circuit in respect to the power consumption, propagation delay and leakage power in the future.   

  • 31.
    Day, Kristi
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Gunnarsson, Elin
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Book Cover Process - some Swedish publishers work with authors and designers in the creation of book covers2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The market for book publishing has changed over the past years. Now the publishers has more pressure on them the to make a profit and every book must now be an economic investment. Meanwhile, more and more new publishers that start up their businesses and every year the competition gets tougher. This leeds to a higher demand on every individual book. The book cover is the face of the book and is supposed to entice the buyer while at the same time represent what's behind the cover. Them significance of the book cover is big and there are high demands that it should fill its function and at the same time help to sell the book.mSeven Swedish publishers has been interviewed for this research paper: Albert Bonniers Förlag, Berghs Förlag, Brombergs Bokförlag, En Bok För Alla (EBFA), Harlequin, Kabusa Böcker, and Opal bokförlag. They have been questioned about how their process in making their book covers in order to investigate if the processes differ from each other or if they are similar. Publishers today don't, for the most part, have a clearly structured process of how they proceed when important book covers are created and there is no time to conduct market analysis and target group analysis for each book. Publishers do, however, find their cover designers in a similar way and many of the publishers use a few regular designers who know the publishers' work process from previous experience. Although, the publishers' attitude toward the author's involvement is similar between publishers, with few exceptions, in the sense that the author himself or herself may determine their own level of involvement. The publishers adjust to what the author prefers. In general, Swedish authors have little authority in the final decision making stage, however they can give suggestions and participate in discussions. This thesis provides insight into how these publishers reason in regards to the bok cover design process and how decisions are made. What is clear is that publishers often rely on their experience, rather than an elaborate analysis of a particular book when a decision is made regarding the cover. However, this is probably due to time constraints which do not make it reasonable to perform a market analysis for each new title a publisher issues. Had there been a clearer working structure of the cover process, maybe more time could be spent on market response.

  • 32.
    Klarin, Niklas
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Delivering of building documents2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The construction business contains an intense flow of information among different actors in different stages of the building process, which demands an effective and functioning way of delivering information. With contracting where the construction starts before the projection is finished it is critical that the projection follows the time plan in order to get all the construction documents approved on time.

    The purpose of this work is to examine the reasons that construction often is delayed due to late approval of the construction documents. The report will also investigate how this can be prevented and finally reach a recommendation for companies how to avoid these kinds of delays. This will be done by studies of relevant literature and interviews of different actors in the business. The study points out time pressure as the main reason for the lack of construction documents.

    The delay of construction documents is often related to delayed or defaulted deliveries of information, and late changes in the project. In this case, the suppliers also play an important role, by involving the suppliers in an early stage of the project, and to sustain a good communication the suppliers can be well involved in the process, and these kinds of delays can be avoided.

  • 33.
    Carlsson, Per
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Personal TV Channels2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Personal TV Channel concept, still in an early stage of research, will record all TV programmes of interest in separate virtual channels (news channel, TV-series channels, movie channels) based on your preferences. The concept has been well received and this report investigates the technical issues and possibilities of creating Personal TV Channels. The development was done mostly as stand alone applications but also by extending to the open-source Linux PVR software MythTV. The experimental results using video ngerprint techniques shows a high accuracy for nding the starting points for TV-series and news broadcasts. The developed visualisation tool provides a clear output of the broadcast segmentation. The segmentation and matching of commercials outputs extensive commercial statistics and makes it possible to track the broadcast of specic commercials. Finally conclusions and future work are presented.

    Keywords : Video Scene Boundary Detection, Commercial Detection, Video Fingerprinting, Video Indexing, Content Analysis, Pattern Recognition

  • 34.
    Kasumovic, Anel
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Määttä, Mikael
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Jämförelse mellan platsbyggt- och prefabricerat mellanbjälklag2008Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The decision about which constructing method that will be used must be taken in an early stage of planning. There are many different methods in order to construct one and a same part of a building. In this report, we describe two construction methods for flooring elements. The choice of construction method is a current question on Åhlin & Ekeroth AB and the company is on an expansive advance. In order to make their methods more efficient the task of investigating this matter has been given to us. Our main goal is to decide whether it is more appropriate to build a flooring element on-the-spot or with prefabricated flooring- cassettes.

    We had the possibility to observe an ongoing project in a district called Lambohov and decided to make an investigation of which type of wooden beam is most suitable for small buildings. We mention two kinds of beams in this report. One of them is called the masonitebeam and the other one is an ordinary beam.

    In order to give the report a larger genuine value we implemented interviews of persons with appreciable experience within the construction industry. Their opinions and knowledge has been to a big assistance in our researching. It has also emerged a lot of exciting facts due to our strategy to give the persons plenty of room during the interviews.

    In order to get closer the truth about which construction method that is most appropriate for small houses we also performed some economical calculations. Despite of everything it is the economic factor that often decides which constructing method that will be used. We know that the prefabricated flooring- element has a higher price and installation cost but is constructed much faster. The question of which constructing method is the economic most favourable in contrast to the total cost remains to be answered and we would recommend a wider research in this matter.

    We hope that the report will be a basis in the future for Åhlin & Ekeroth AB when the company carries out similar projects as the ones on Kv Isglassen and Kv Isskulpturen.

  • 35.
    Gangadharan, Venkata Krishnan
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, The Institute of Technology.
    Conceptual Design Tool for Aircraft Electrical System2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The conceptual design stage of an aircraft involves many uncertainties with regard to prediction of weight of systems. The current trend is that electrical systems increasingly replace hydraulic and pneumatic systems in an aircraft. This leads to greater uncertainty in weight, size and power requirement prediction.

    This work is an attempt at developing a sizing tool that will allow users to estimate the power requirements and weight of electrical systems for a given size of an aircraft specified either by passenger capacity or by aircraft operating empty weight or by maximum take-off weight.

    As with all predictive tools, the results of this work are based on currently available data, i.e., the specification of existing aircraft. This collection of specification of existing aircrafts would constitute the data library. The accuracy of the result of this work depends greatly on the variety of aircrafts and the level of detail for which the data is available.

    The tool is made in Microsoft Excel with some codes made in VBA to perform Excel calculations.

  • 36.
    Unoson, Alexander
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    A study of the tendering stage process when introducing new quality systems2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Almroth Byggnads AB är mitt i processen att revidera sina olika ledningssystem. Entré, som nyligen började användas som ekonomiledningssystem, i ett steg på vägen för att kunna utvecklas till ett verksamhetsledningssystem. Dit ska man komma genom att samarbeta med Povel, ett branschanpassat ledningssystem för alla typer av byggföretag. Detta kräver mycket justering av dokument för att passa Almroth, då Povels dokument är väldigt generella, och gäller både stora och små företag. Det finns styrande dokument för anbudsskedet i Povel, de är sådana att de måste justeras för att passa Almroth. Denna studie tar reda på vad som bör ingå i Almroths dokument, vad Almroth bör gå igenom från det att man får in en anbudsförfrågan tills arbetet med anbudet är färdigt och om ledningssystemet kommer medföra att Almroths arbete med anbud blir effektivare. De styrande dokumenten jag tar fram ska vara utformade så att de når kraven i ISO 9001, ISO 14001 och AFS2001:1. Jag har undersökt vilken typ av arbeten man har och hur man bör gå till väga vid olika typer av entreprenader och upphandlingar. Mina resultat av teori och empiri om anbudsskedets process är presenterade i kapitel 4, där gör jag även en analys över hur ledningssystemen kommer påverka anbudsprocessen och snuddar även lite bredare runt dessa system. Vidare finns mina checklistor och rutinbeskrivning som bilagor, med grund i kapitel 4 och 5, analysen samt mina slutsatser.

  • 37.
    Fallhagen, Johanne
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Passivhus– framtidens boende?2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, the residential- and service sector accounts for approximately 40 percent of Sweden's energy usage. Therefore it is important to take measures for efficient use of energy, one way to do that is to reduce the energy used for heating. Energy consumption in a passive house is about a quarter of the consumption of a traditional house.

    Passive houses are well insulated and tight buildings that are largely heated by the energy already present in the house. The residents and their household appliances are very important sources of energy. Because of reduced heat loss, there is no need for radiators or underfloor heating. Since the passive house is so tightly built, all the ventilation occurs through the ventilation system and not through leaks in the construction. A heat exchanger for ventilation air helps to warm the fresh air from the already warm, used air. This way it recycles 85 percent of the heat energy.

    In general, it costs a few percent more to build a passive house than a traditional house, but the extra cost is repaid in just a few years due to the significantly lower energy costs. 3D-visualization is something that is becoming more common in the construction industry. It is not easy, especially not for the untrained eye, to understand a drawing in 2D. By creating a 3D-model of a building in the planning stage of a project, you can see how it will look like when it is built. I have created a 3D-model of a passive house in form of a terraced house. The visualization shows an alternative design of a typical flat with three rooms and a kitchen.

  • 38.
    Andersson, Erik
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Visualisering av butik2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The examination work is about using the knowledge I have gained during my education as a construction engineer, to visualize how a modification of an existing house could look like. The present building is used for stores on the first floor and offices on the second floor. With the rebuilding the entire building will become a shopping mall.

    My client is Sonark Arkitektkontor AB, which in it's turn works on behalf of property company Klövern AB. As starting material I have had the architects first concept sketches and old drawings of the building. I have performed the work in 3D Studio Max and Adobe Photoshop. My work has concluded in exterior still photos and a short movie clip from the inside of the building.

    This material, the orderer and consulting firm has been using to convince themselves that this is how they want to design the building, but in later stages, the presentation material is demonstrated for the municipality at the department of building permit issues and at the last stage pictures has also been used to sell the real estate to new roomers.

  • 39.
    Bajt, David
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Real-time Simulation of Volumetric Stage Light2008Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As current pre-visualization applications for the stage lighting industry only is developed for the PC-market, this master thesis can be considered as the first graphics engine prototype implementation of a completely new visualizer, not only for Mac, but for all platforms.

    The result is a cross-platform application in real-time, fully concentrated in simulating a real stage spotlight which not only illuminates surfaces, but also the air itself, referred to as volumetric light. In order to achieve such a phenomenon, a texture-based approach is used, mainly implemented in a fragment shader and therefore takes full advantage of the powerful Graphics Processing Unit (GPU).

    Similar to traditional ray tracing based algorithms, the method calculates light intensity on a per-pixel basis by integrating scattered light along the ray. The algorithm can also render surface shadows, shadow holes and create gobo effects in the volumetric lighting using a shadow mapping method. As the quality of light, shadows and surface characteristics are one of the most competitive features in a modern visualizer, these attributes are of greatest concern. I n order to alter light source parameters such as light intensity, color, zoom, etc. during run-time, a simple graphical user interface (GUI) is also attached to the application.

    I n brief, this master thesis stands as the “proof of concept”, i.e. a study if the latest real-time graphics technology, including OpenGL- and shader programming, often used in Windows environments also can be used for volumetric stage light simulations in a Macintosh environment.

  • 40.
    Grabowska, Kamila
    et al.
    Linköping University, Department of Management and Engineering. Linköping University, Faculty of Arts and Sciences.
    Tabe Mohammadi, Shideh
    Linköping University, Department of Management and Engineering. Linköping University, Faculty of Arts and Sciences.
    Ex-ante Control Mechanisms against Opportunistic Behavior regarding Knowledge Sensitivity of Product (Comparative Case Study)2013Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    There is an increasing interest for business organizations to engage into the global inter-firm alliance nowadays. The companies are striving for accessing the opportunities created by emerging markets, diversification of the products’ offer or the access to lower cost inputs (Barnes, et al., 2010). However, along with the benefits, there are also risks that the inter-firm alliances are challenged with. Those risks are represented by various forms of opportunistic behavior, which might be further caused by business partners (Williamson, 1975). The companies that decide to engage into inter-firm alliance need to invest in the implementation of control mechanisms that will protect them against opportunistic behavior. The preventing exante mechanisms can be implemented prior to the official start of cooperation while the cause ex-post mechanisms are applied during further stage of the collaboration. However, due to the cost of these implementations, companies cannot afford employing every available control mechanism. They need to select only the ones that their benefits exceed their costs. One of the main factors that influence the selection process of control mechanisms is the level of knowledge sensitivity of a product. The main objective of this master thesis is to determine how the level of knowledge sensitivity of a product influences the selection of ex-ante control mechanisms.

  • 41.
    Ali, Baland
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Peuravaara, Mattias
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Grävmaskinsstyrning med en eller två GNSS-mottagare2008Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today's increasing demand for greater efficiency in the construction industry has led to the need for corporate machines to be modernized to keep up with competitors. The modernization can be of different natures, amongst other the introduction of dual satellite based receivers on excavators that NCC Construction want investigated.

    The imposition of machine control systems with dual satellite based receivers, GNSS-receivers, is alleged to contribute to efficiency and a higher degree of accuracy. This report is a comparison of the relatively new system that uses two receivers with at this stage frequently used system with only one receiver.

    The comparison has been conducted by field measurements, calculations based on theoretical models and interviews with, in the field, qualified staff. The report also deals with economic aspects, in which the calculations are simplified, in order to get an overall picture of the costs and potential savings´for a possible future investment. Upgrading to machine control systems with dual GNSS-receivers did not show any major improvement when positioning the bucket. Despite the fact that a theoretical analysis shows that the positioning should be improved considerably.

    The reason for the lack of improvement could be that too few machines were examined. The survey shows that such an advanced technology as GNSS machine control requires careful maintenance in order to achieve expected accuracy. Economically, it appears that systems with two receivers are a good alternative in the event of an investment. However, which of the excavators to be equipped with the system, should be carefully evaluated depending on the excavator main tasks.

  • 42.
    Lundell, Johan
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Efficiency Enhancement Techniques for a 0.13 µm CMOS DECT PA2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Different efficiency enhancement techniques for a 1.9 GHz DECT power amplifier (PA) have been investigated. Generally, a higher efficiency can be achieved by varying the supply voltage and/or the bias of the PA or by making topology and/or class changes. In this work, changes in bias and topology have been studied. Focus has been on enhancing efficiency at power back-off to increase talk-time for handset applications. The PA used in this study was a two stage 0.13 μm CMOS PA for 2.5 V operation. In its original

    configuration, it delivered 28.3 dBm of maximum output power with a PAE of 43.5 % (simulated). At 10 dB power back-off the PAE was only 15.9 %. The largest improvement was obtained using a topology change with the amplifying transistor split into two parallel transistors (class A and B) with variable bias. The PA delivered 29.1 dBm to the load with a PAE of 45.1 %, and 18 % PAE at power back-off; a relative improvement at this level with 13 %. The new PA topology does not require any additional area.

  • 43.
    Jakobsson, Anders
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Amplitude path for a polar modulation transmitter2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    this is master tesis on characterisation and implementation of amplitude path for a polar modulation transmetter, targeted at bluethooth extended data rate ( EDR).bluethooth EDR uses quadrature modulation techniques to obtain higher data rates. these techniques use ampitude an phase modulation of a carrier to increas bitrate without increasing signal bandwidth compared to anly using amplitude or phas modulation. the amplitude path migjt be futher developed by investigating the use of higjer order anti-elaising filters together with group compesation. alternative solutions for the I/V-stage is also an important area of staudy.

  • 44.
    Köpsell, Linn
    Linköping University, Department for Studies of Social Change and Culture, Culture, Society, Media Production. Linköping University, Faculty of Arts and Sciences.
    MAGISKA RUM: om scenografins roll i scenkonstverk för barn och unga2013Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    This thesis investigates the communicative role of scenography in the performing arts for children, with an aim to make the readers understand the ways in which a set design can be optimized so that a young audience can be able to interpret the play and its message.

    The art of scenography is complex and includes many elements. The research questions can therefore be grouped into three clusters: one artistic oriented (How does the scenographic process work and what is its relation to the scenic piece at large? In which ways may scenography be used to support the desiderate interpretation?), one audience oriented (Which work processes enhances the chances of creating dramatic art that is perceived as meaningful to the audience? On what premises can the semiotics of theatre be used in the performing arts for a young audience?) and last a cluster that focuses on Den magiska cirkeln (The Magic Circle) by ung scen/öst (What is told in the show and how is this portrayed in the scenography? Who is in the target group, and does the audience get the feeling of the performance as intended?).

    Den magiska cirkeln is used as a case study in the thesis in order to reflect the theoretical material. Methods in the case study includes performance analysis, a survey completed by 178 people in the audience and an interview with scenographer Anna Dolata. 14 performing analyzes of Swedish children’s theatre shows have been made in addition to the case study.

    The thesis analyses and compares two work logics; the internal logic and the external logic, and it is shown that meaningful interpretations are likelier to happen with an external logical point of view. But the result is not unequivocal; a performance without any internal logic is likely to fall flat as the performance needs to be extracted from the creators’ full conviction.

    As shown in the thesis, scenography can be used to amplify the readings and intents with usage of the semiotics of theatre. It is important not to overlook the great potential of scenography in order to enhance the experience. The thesis also shows that the intentions that ung scen/öst had with Den magiska cirkeln went past many in the audience. Many felt that the show was confusing, and expressed frustration at not having solved the performance’s message. A high level of knowledge about the audience, and a willingness to listen and absorb its opinions, increases the chances of creating meaningful performances.

    Key words: scenography, stage design, set design, stage art, performing arts, theatre, children’s theatre, theatre semiotics, ung scen/öst

  • 45.
    Carlsson, Staffan
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Skillnader i mulmvolymer mellan fem trädslag i Östergötlands eklandskap2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Old hollow trees of oak contain a large amount of wood mould. Unfortunately, these trees have in the last century been greatly reduced in numbers. It has resulted in that species that depend on these habitats, saproxylic species, have become at risk to decrease in numbers or die out regionally. Previous studies have shown that the volume of wood mould is an important factor for occurrence and population size of saproxylic organisms. The aim of the present study was to examine how the volume of wood mould varies among ash (Fraxinus excelsior), lime (Tilia sp.), maple (Acer platanoides), aspen (Populus tremula) and oak (Quercus robur). The measurements were wood mould depth, internal cavity diameter, internal cavity height, circumference, and if white or brown rot was the dominating mould fungus. In total 23 ashes, 20 limes, 24 maples, 24 aspens and 21 oaks in the vicinity of Motala (Östergötland) were measured. The results show that there were significant differences between tree species concerning the volumes of wood mould. The oak accommodated larger volumes than the other species. The ash, however, had a larger volume than oak at the same circumference. The study shows ash could be a complement to the oak in conservation plans. Since the ash generally holds a larger volume then the oak at the same circumference, this implies the possibility that the ash can be suitable for saproxylic organisms at an earlier stage. In the isolated fragments of the landscape the possibility for survival may then increase for species that are dependent of these habitats.

  • 46.
    Abdul Aziz Hasan Ali, Aamir
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Shahzad, Muhammad Adil
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    A Joint Subcarrier/Power allocation Scheme for OFDMA-based Cellular Networks2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The assignment of this master thesis consists of initiating power, subcarrier allocation in a dynamic FFR based scheme designed for multi-cell OFDMA networks and to enhance the throughput of all center users in bandwidth hungry borrower cells (overloaded cells) which was previously degraded by original FFR3 scheme as a result of partitioning of system bandwidth into center and edge bands respectively. The method uses band borrowing to compensate center user’s throughput loss in a semi and fully overloaded system. The scheme uses dynamic programming method (0/1 knapsack problem) to bargain an edge band on various power levels and tends to check the best combination (power and sub-carrier) which the system can utilize while still maintaining acceptable throughput loss for the users at the edge of the neighboring cell (lender cell).

    The algorithm consists of generating a borrowing request to neighboring cells for utilizing their edge bands by the overloaded borrower cell if their average center user throughput reaches below a minimum threshold value set in the system. The borrowing method uses 0/1 knapsack problem to capture an edge band based on limiting factors of total cost in average throughput losses by neighbors (Ci) and Un (tolerable mean user edge user throughput loss by lending cell). While solving knapsack problem the lender (neighbors) will check Ci and Un before granting the right to use its edge band. The later stage requires reducing subcarrier power level in order to utilize the lenders edge band using "soft borrower" mode. The borrowed sub-carriers will be activated take power from the original center band sub-carriers of the overloaded cell by taking into account the interference between the lender and the borrower. In case of negative (0) reply from the lender cell after the first request, multiple requests are generated at reduce power level at every step to order to acquire more bands. If a neighbor has band borrowing requests from multiple overloaded base stations, the band will be granted to the one which gives minimal loss in terms of throughput to the lender cell.

    The simulation results are analyzed w.r.t reuse-1 and FFR3 scheme of a multi cell regular and irregular scenarios comprising of lightly to heavily overloaded cells with various subcarrier allocation patterns. An overhead and time assessment is also presented between borrower and lender cells. Simulation results show an increase of 60% in center user’s throughput w.r.t original FFR3 scheme with an acceptable loss of 18% at the edges in complex overloaded scenarios while the overall system throughout increases by 35%.

  • 47.
    Cervin, Albert
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Adaptive Hardware-accelerated Terrain Tessellation2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this master thesis report, a scheme for adaptive hardware terrain tessellation is presented. The scheme uses an offline processing approach where a height map is analyzed in terms of curvature and the result is stored in a resource called density map. This density map is then bound as a resource to the hardware tessellation stage and used to bias the tessellation factor for a given edge. The scheme is implemented inside FrostbiteTM2 by EATM DICETM and produces good results while making the heightfield rendering more efficient. The performance gain can be used to increase the rendering detail, allowing for better visual appearance for the terrain mesh. The scheme is currently implemented for hardware tessellation but could also be used for software terrain mesh generation. The implementation works satisfactory and produces good results with a reasonable speed.

  • 48.
    Bhaskar Gudey, Bala
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Kane, Jacob
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Co-Design of Antenna and LNA for 1.7 - 2.7 GHz2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In a radio frequency (RF) system, the front-end of a radio receiver consists of an active antenna arrangement with a conducting mode antenna along with an active circuit. This arrangement helps avoid losses and SNR degradation due to the use of a coaxial cable. The active circuit is essentially an impedance matching network and a low noise amplification (LNA) stage. The input impedance of the antenna is always different from the source impedance required to be presented at the LNA input for maximum power gain and this gives rise to undesired reflections at the antenna-LNA junction. This necessitates a matching network that provides the impedance matching between the antenna and the LNA at a central frequency (CF). From the Friis formula it is seen that the total noise figure (NF) of the system is dependent on the noise figure and gain of the first stage. So, by having an LNA that provides a high gain (typically >15 dB) which inserts minimum possible noise (desirably < 1 dB), the overall noise figure of the system can be maintained low. The LNA amplifies the signal to a suitable power level that will enable the subsequent demodulation and decoding stages to efficiently recover the original signal. The antenna and the LNA can be matched with each other in two possible ways. The first approach is the traditional method followed in RF engineering where in both the antenna and LNA are matched to 50 Ω terminations and connected to each other. In this classical method, the antenna and LNA are matched to 50 Ω at the CF and does not take into account the matching at other frequencies in the operation range. The second approach employs a co-design method to match the antenna and LNA without a matching network or with minimum possible components for matching. This is accomplished by varying one or more parameters of either the antenna or LNA to control the impedances and ultimately achieve a matching over a substantial range of frequencies instead at the CF alone. The co-design method is shown to provide higher gain and a lower NF with reduced number of components, cost and size as compared to the classical method.

    The thesis work presented here is a study, design and manufacturing of an antenna-LNA module for a wide frequency range of 1.7 GHz – 2.7 GHz to explore the gain and NF improvements in the co-design approach. Planar micro strip patch antennas and GaAs E-pHEMT transistor based LNA’s are designed and the matching and co-design are simulated to test the gain and NF improvements. Furthermore, fully functional prototypes are developed with Roger R04360 substrate and the results from simulations and actual measurements are compared and discussed

  • 49.
    Abbasi, Muneeb Mehmood
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Jabbar, Mohammad Abdul
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Design and Performance Analysis of Low-Noise Amplifier with Band-Pass Filter for 2.4-2.5 GHz2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Low power wireless electronics is becoming more popular due to durability, portability and small dimension. Especially, electronic devices in instruments, scientific and medical (ISM) band is convenient from the spectrum regulations and technology availability point of view. In the communication engineering society, to make a robust transceiver is always a matter of challenges for the better performance.

    However, in this thesis work, a new approach of design and performance analysis of Low-Noise Amplifier with Band-Pass filter is performed at 2.45 GHz under the communication electronics research group of Institute of Science and Technology (ITN). Band-Pass Filtered Low-Noise Amplifier is designed with lumped components and transmission lines. Performances of different designs are compared with respect to noise figure, gain, input and output reflection coefficient. In the design process, a single stage LNA is designed with amplifier, ATF-58143. Maximally flat band-pass (BPF) filters were designed with lumped components and distributed elements. Afterwards, BPF is integrated with the LNA at the front side of LNA to get a compact Band-Pass Filtered Low-Noise Amplifier with good performance.

    Advanced Design System (ADS) tool was used for design and simulation, and each design was tuned to get the optimum value for noise figure, gain and input reflection coefficient. LNA stand-alone gives acceptable value of noise figure and gain but the bandwidth was too wide compared to specification. Band-Pass Filtered Low-Noise Amplifier with lumped components gives also considerable values of noise and gain. But the gain was not so flat and the bandwidth was also wide. Then, Band-Pass Filtered Low-Noise Amplifier was designed with transmission lines where the optimum value of noise figure and gain was found. The gain was almost flat over the whole band, i.e., 2.4-2.5 GHz compared to LNA stand-alone and Band-Pass Filtered Low-Noise Amplifier designed with lumped components. It is observed that deviations of results from schematic to layout level are considerable, i.e., electromagnetic simulation is needed to predict the Band-Pass Filtered Low-Noise Amplifier performance.

    Prototype of LNA, Band-Pass Filtered Low-Noise Amplifier with lumped and transmission lines are made at ITN’s PCB laboratory. Due to unavailability of exact values of Murata components and for some other technical reasons, the measured values of Band-Pass Filtered Low-Noise Amplifier with lumped components and transmission lines are deviated compared to predicted values from simulation.

  • 50.
    Maruf, Md Hasan
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    An Input Amplifier for Body-Channel Communication2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Body-channel communication (BCC) is based on the principle of electrical field data transmission attributable to capacitive coupling through the human body. It is gaining importance now a day in the scenario of human centric communication because it truly offers a natural means of interaction with the human body. Traditionally, near field communication (NFC) considers as a magnetic field coupling based on radio frequency identification (RFID) technology. The RFID technology also limits the definition of NFC and thus reduces the scope of a wide range of applications. In recent years BCC, after its first origin in 1995, regain importance with its valuable application in biomedical systems. Primarily, KAIST and Philips research groups demonstrate BCC in the context of biomedical remote patient health monitoring system.

    BCC transceiver mainly consists of two parts: one is digital baseband and the other is an analog front end (AFE). In this thesis, an analog front end receiver has presented to support the overall BCC. The receiver (Rx) architecture consists of cascaded preamplifier and Schmitt trigger. When the signals are coming from the human body, they are attenuated around 60 dB and gives weak signals in the range of mV. A high gain preamplifier stage needs to amplify these weak signals and make them as strong signals. The preamplifier single stage needs to cascade for the gain requirement. The single stage preamplifier, which is designed with ST65 nm technology, has an open loop gain of 24.01 dB and close loop gain of 19.43 dB. A flipped voltage follower (FVF) topology is used for designing this preamplifier to support the low supply voltage of 1 V because the topology supports low voltage, low noise and also low power consumption. The input-referred noise is 8.69 nV/sqrt(Hz) and the SNR at the input are 73.26 dB.

    The Schmitt trigger (comparator with hysteresis) is a bistable positive feedback circuit. It builds around two stage OTA with lead frequency compensation. The DC gain for this OTA is 26.94 dB with 1 V supply voltage. The corner analyzes and eye diagram as a performance matrix for the overall receiver are also included in this thesis work.

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