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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.
    Hellquist, Stina
    et al.
    Linköping University, Department of Management and Engineering, Carl Malmsten - furniture studies.
    Lindberg, Malin
    Linköping University, Department of Management and Engineering, Carl Malmsten - furniture studies.
    Giftfritt och effektivt: Om att göra kloka val i tapetserarverkstaden2015Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Can we as upholsterers work effectively and nontoxic using plates in natural materials as filling in furniture?

    In our work we have investigated renewable natural materials in plates and how they work as furniture filling. We want to find out what products are available and examine what their possibilities and limitations are.

    We have inventoried the supply of Swedish retailers and we have tested products made for furniture but we have also tried isolation plates in flax and hemp from the construction industry. Through practical tests we l earned how well the materials are suitable for various upholstery techniques. Based on the tests we chose some products to use in our work on restoring an armchair and a sofa. After performing the tests and working on the furniture we have summarized the results, including time saving aspects and cost. We have found that hemp insulation is an affordable material that works very well as filling material in furniture. This work can form the basis for the upholsterer who wants to shift to a sustainable way of working. We believe the future lies in finding ways to work more effectively with natural materials. The plates are one way to do it

  • 3.
    Gustafsson, Daniel
    et al.
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics.
    Larsson, Isak
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics.
    Solvärme i Singapore2015Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The world faces big issues regarding its energy supply and its impact on the environment. Something has to be done in order to stop this. One way to do that is to make energy generation more sustainable by shifting from fossil fuels to renewable energy sources. Solar energy is one of them, and this report covers hot water produced from it.

    A country that should have good conditions to harvest solar power is Singapore. The country has a very limited land area and almost no natural resources. Because of this, most of its energy is supplied by imported natural gas. In this report, a case has been created to evaluate the performance and profitability of a hot water solar system in a villa in Singapore. In order to do this, literature about the sun, solar heating systems and Singapore has been looked into. Further, thermodynamical correlations have been studied and used in calculations to draw conclusions.

    The result of this report is that an installation of a solar water heating system in a villa in Singapore is feasible and profitable. Other applications of solar thermal power have been evaluated qualitatively and the conclusion is that these also have big potential in Singapore. Ultimately, this could lead Singapore to be less relying on imported energy and also reduce its impact on the environment.

  • 4.
    Steen Lagerstam, Nathalie
    Linköping University, Department of Management and Engineering, Project Innovations and Entrepreneurship.
    Expansion av e-handelsverksamhet i detaljhandeln: En studie om utmaningar och framgångsfaktorer2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Internet has become a central part of the modern society and has change our everyday life in many ways. An area that’s been strongly affected by this development is the Swedish retail e-commerce market. E-commerce sales have increased six-fold over the course of the past decade and forecasts indicate that this expansive trend will continue. This trend places significant challenges on Swedish retail companies who have a legacy of exclusively carrying out their sales in the traditional brick and mortar format. The subject of this study was originally proposed by the Swedish retail company Företag X[1], who have decided to embark on their e-commerce initiative in early 2016. Företag X asked the author of this report to help with finding out what it takes to develop a small e-commerce store, in such a way that it becomes a successful part of the company, contributing to the company’s overall profitability. The purpose of this study is therefore to identify practices and methods that enable successful expansion of e-commerce for medium-sized, Swedish retail companies.

    In order to achieve the purpose, a qualitative multi-case study design was chosen for the study. Information for the theoretical framework was collected from articles in scientific journals and books, and supplemented with secondary empirical data in the form of reports from companies. Qualitative primary data were then collected from interviews with three chosen companies, which were found with through a small cross-sectional study of 20 competitors to Företag X where their EBITDA margins over the past five years were studied.

    The study results showed an expansive trend on the Swedish retail e-commerce market, and it seems that this trend is set to continue over the next decade. As a consequence, market climate is changing and shifting towards becoming more digitalized, which requires companies to review their sales organizations. The main trend in the market is called “omni-channel retailing" and means that a company is integrating its brick and mortar and e-commerce sales to enable a seamless shopping experience for the customer. This trend has emerged as a response to a new buying patterns observed among customers, who move between their digital and physical sales channels during the purchase.

    The study indicates that the e-commerce-related issues that are most important to address and work with are in the following areas:

    • Customer Focus
      • IT
      • Customer relations
      • Responsiveness to customers
    • Cost effectiveness
      • Supply chain and logistics
      • Strategy and governance
    • Resistance Management
      • Education
      • Synchronization between brick and mortar stores and e-commerce store

    This study represents the author’s master’s thesis in the Industrial Engineering and Management program at Linköping University, Sweden.

    [1] Företag X are known by a different name, but have asked to remain anonymous in this study

  • 5.
    Ledin, Staffan
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems.
    A Comparison of Radix-2 Square Root Algorithms Using Digit Recurrence2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When designing an electronic system, it might be desirable to implement a custom square root calculator unit to ensure quick calculations. The different questions when it comes to square root units are many. What algorithms are there? How are these algorithms implemented? What are the benefits and disadvantages of the different implementations? The goal of this thesis work is to try to answer these questions. In this paper, several different methods of calculating the radix-2 square root by digit recurrence are studied, designed and compared. The three main algorithms that are studied are the restoring square root algorithm, the non-restoring square root algorithm and the SRT (Sweeney, Robertson, Tocher) square root algorithm. They are all designed using the same technology and identical components where applicable. This is done in order to ensure that the comparisons give a fair assessment of the viability of the different algorithms. It is shown that the restoring and non-restoring square root algorithms perform similarly when using 65 nm technology, a 16 bit input, full data rate and 1.2 V power supply. The restoring square root algorithm have a slight edge when the systems are not pipelined, while the non-restoring algorithm performs slightly better when the systems are fully pipelined. The SRT square root algorithm perform worse than the other two in all cases.

  • 6.
    Bostedt, Robert
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Bitcoin & valutakonkurrens: En jämförande nyttoanalys2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper investigates the fulfillment of utility in the currency Bitcoin in relation to the Swedish krona in general andthe macroeconomic consequences of such fulfillment of utility in particular. The paper starts with the assumption thatthe utility generated by money is deduced from its qualities, mainly the quality in storage of value and the currency´spossibilities of generating low transaction costs. The investigation finds that there are possibilities that Bitcoin maygenerate a higher utility for its users than the Swedish krona under some circumstances. This mainly from Bitcoinsqualities in storage of value due to its predetermined change in money supply and in times when the Swedish krona´smonetary base is expanded by monetary policy and its subsequent inflation. In such periods when monetary expansionis undergoing in the Swedish krona, the investigation finds that the expected higher utility in Bitcoin in relation to theSwedish krona may cause a change of individuals incentives for currency, away from the Swedish krona and towardsBitcoin, if the profit gained from such change for an individual is great enough. From this, the central analysis ofBitcoins consequences on macroeconomic level follows. If there is an opportunity to change currency, which causesutility profits for individuals, there is also risk that the stimulus in monetary policy fails. This due to the decrease ofpurchasing power in the Swedish krona due to the lower demand of the currency in question subsequent to its loss init’s quality of storage of value. The analysis finds that depending on which theoretical perspective that is used, systemicrisks stemming from Bitcoin usage can be found in an analysis made with the Keynesian perspective. This while theopposite, that the systemic risks are introduced in the economy with the Swedish krona, is the result of an analysis madewith the Austrian theory of business cycle. Even with the systemic risks identified in the Keynesian analysis, reformsare suggested so that Bitcoin is able to co-exist with Keynesian monetary institutions to be able to take care of the utilitygained on the microeconomic, individual level that may result from Bitcoins usage as means of trade.

  • 7.
    Back, Lovisa
    et al.
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Johannisson, Emma
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Ransoneringar på policy- och individnivå i hälso- och sjukvården - Ett beteendeekonomiskt experiment: Health Care Rationing at Policy and Bedside Level - A behavioral economic experiment2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: Scarce health care resources fail to supply the increasing demand. In order to allocate the economic resources as efficiently as possibly the capacity to ration, to deny patients health care, is essential. Rationing decisions can be considered as moral dilemmas where the decision maker is required to choose between two conflicting ethical principles. However, the conditions under which policymakers and physicians make decisions are different. Many policies are not applicable at the bedside level since they are based on a group perspective and tend to ignore a patient's individual needs.Aim: The aim of this study is to conduct a behavioural economic experiment and examine how the context of the decision-maker influences the outcome of their decision in health care rationing situations.Method: Medical students and students from other graduate programmes receive a questionnaire where they each make decisions in rationing scenarios where utilitarian and deontological principles are in conflict. Each survey is framed as a decision presented in one of two decision-making contexts, policy or bedside level. At policy level, the subjects assume the perspective of a head of department and make decisions regarding a patient based upon a group statistic. At bedside level, the subjects take the perspective of a physician and make decisions regarding an identified patient.Results: Subjects are more utilitarian and ration to a higher degree at policy level than at bedside level. The difference in the rate of utilitarian answers at policy level in comparison to bedside level is largest for medical students and in life saving scenarios. Students from other graduate programmes, however, are more likely to ration at policy level. In life enhancing scenarios, the effect of the decision-making context differs and the rate of utilitarian responses is in some cases lower at policy level than at the individual level.Conclusion: This study shows that decisions at the policy and the bedside level are not necessarily the same, even though the available information of the treatments and costs remains unchanged. This result encourages further studies on the impact of the decision-making context on rationing decisions in health care.

  • 8.
    Olsson, Tom
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Coordination of material flows and operations flows at the FUS in Linköping2015Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Examensarbetet Koordinering av materialflöden och verksamhetsflöden vid FUS i Linköping genomfördes för att ge stöd åt beslutsfattande gällande flödet av byggnadsmaterial från den norra godsmottagningen av sjukhuset till den östra utbyggnaden under året 2015.

  • 9.
    Fellenius, Beatriz
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Mapping and evaluation of the purchasing process at Ahlvar2015Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Modebranschen är en ständigt föränderlig bransch som präglas av långa ledtider, osäkra prognoser och starkt trendfokus. Ahlvar By Frida Ahlvarsson är ett svenskt modeföretag som verkar inom just denna bransch. Ahlvar upplever precis som många andra små modeföretag problem kopplade till branschens uppbyggnad. Problemen som företaget upplever är främst ekonomiska men har också att göra med höga lagernivåer och hög arbetsbelastning. I detta arbete görs en granskning av Ahlvars inköpsprocess med hjälp av Business Process Management (BPM) för att identifiera orsakerna bakom de problem som företaget upplever. Det fastslås att företagets ekonomiska problem främst är kopplade till höga produktionskostnader medan de höga lagernivåerna främst beror på avsaknaden av statistiska prognoser. Den höga arbetsbelastningen verkar i sin tur ha att göra med det faktum att det som enmansföretag är svårt att handskas med inköpsprocessens många steg och parallella processer. För att identifiera lösningar till dessa problem presenteras teori kring inköpsprocesser och även information om hur tre liknande modeföretag arbetar. De tre andra företagen är Filippa K, Företag X och House of Dagmar. Tillsammans med teorin görs en jämförelse mellan dessa tre och Ahlvar. Jämförelsen visar att det finns många likheter mellan företagen och att mycket av deras arbetssätt har goda kopplingar till teorin. Dock i identifieras även vissa markanta skillnader mellan Ahlvar och de andra företagens arbetssätt. Utifrån jämförelsen fastslås tre huvudsakliga rekommendationer för hur Ahlvar ska förändra sin inköpsprocess i syfte att förbättra sin ekonomiska situation med hjälp av en mer effektiv försörjningskedja. Rekommendationerna är att företaget bör hitta fler leverantörer, byta leverantörsland från Kina till ett eller flera länder i Europa och att börja göra enklare prognoser på tidigare års försäljning. Som en följd av bytet av leverantörsland rekommenderas även företaget att förändra sitt val av transportslag från flygplan till lastbil och båt vid frakt av produkter.

  • 10.
    Bandla, Atchaiah
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Highly Linear 2.45 GHz Low-Noise Amplifier Design2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    One critical component of the communication receiver of front-end system is the low-noise amplifier (LNA). For good sensitivity and dynamic range, the LNA should provide a low noise figure and maximum attainable power gain. Another concern is the linearity of the LNA. Strong signals produce intermodulation products in a frequency band close to the operating frequency that might affect the performance of the receiver. In many cases, the intermodulation products can be reduced by increasing the current through the active device. Hence, a trade-off between power consumption and linearity must be considered when designing the LNA. The thesis includes the bias network design, stability analysis, matching network design and layout design of the LNA RF module with layout simulation. The simulation has been performed using Advanced Design System (ADS) simulation software. After implementation of LNA on a PCB, the LNA is measured with the help of the power supply unit and vector network analyzer. The proposed design aim is to provide a low noise figure (NF) and high gain while maintaining the low power consumption.

  • 11.
    Arana Escobedo, André
    et al.
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, Faculty of Science & Engineering.
    Gunnarsson, Oskar
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, Faculty of Science & Engineering.
    Hydraulic Energy Efficiency of Concepts on an Articulated Hauler: Design and evaluation of different hydraulic concepts with focus on energy efficiency2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master's thesis has evaluated dierent system designs for the hydraulic system on an articulated hauler at Volvo Construction Equipment (CE). The current system suers from great losses when running on low pump displacement settings. This is due to large installed displacements as a result of regulations and market demands. New system concepts have been generated and simulations in Matlab and Amesim show that some of the concepts can be implemented in order to increase energy eciency up to 65%. However, increasing eciency does in most cases also increase cost, making some of the concepts unrealistic to implement. The suggested solution for Volvo CE is to remove one pump and allow for the fan pumps to supply oil to the steering and dumping, as described in the Displacement reduction concept. They should also examine the possibility to implement clutches further.

  • 12.
    Johannesson, Maja
    et al.
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Stejmar, Sofie
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Gröna obligationer - Vägen till en mer hållbar kreditmarknad: En studie om aktörers motiv och ekonomiska drivkrafter på den svenska marknaden för gröna obligationer2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: In 2007 the World Bank issued the first green bond in the world in co-operation with SEB. Vasakronan issued the first green corporate bond in 2013 and since then the market has expanded. Green bonds have the same financial characteristics as traditional bonds, the difference being that the proceeds from green bonds have to finance environmental or climate friendly projects. Green bonds give incentives to investors and issuers to implement sustainable investments and projects.

    Aim: The purpose of the thesis is to examine and analyze motives and economic incentives behind the participation of players in the Swedish green bond market. In addition, the thesis maps out the institutional conditions that enabled the emergence of green bonds and highlight the future challenges and prospects.

    Completion: This thesis is a qualitative study of 13 interviews conducted by the authors. The interviewees represent the following groups: issuers, investors, banks and certifiers. A literature review about green bonds is provided to illustrate the characteristics of green bonds and the market. The empiric material is analyzed using institutional theory, game theory, financial theory and CSR theories, as well as previous research about CSR and SRI.

    Conclusion: A number of institutional conditions and individual actions have contributed to the rise and development of the Swedish green bond market. The motives and economic incentives that apply to all the players in the market are the opportunity to enhance a green and sustainable profile, the fact that green bonds have the same financial characteristics as traditional bonds and that they include a green feature. Future challenges for the growth of the green bond market include the development of standards and to increase the supply of green bonds.

  • 13.
    Haglund, Nathalie
    et al.
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Wåhlberg, Frida
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Knowledge transfer between projects: Exploring the receiver’s perspective2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: How to facilitate the knowledge transfer between projects is a field that has obtained a lot of attention in research. Despite this wide attention, many organizations still experience difficulties to efficiently transfer knowledge between their projects and thus the problems still remain, which appears contradictory. Previous research has had a tendency to assume that all knowledge can be articulated and codified, which has resulted in that solutions to these problems often have been directed towards the side in the transfer that creates the supply of knowledge. However, limited research has taken the receiver of the knowledge into consideration when analyzing these difficulties, who is considered to be equally influential to motivate a transfer.

    Purpose: The purpose of this study is to increase the understanding of the challenges concerning the knowledge transfer from past to future projects, by exploring the importance of incorporating the receiver’s perspective in the analysis of knowledge transfer practices.

    Methodology: This study has applied a qualitative research methodology where the empirical data has been obtained through an interview-study with nine onsite interviews in two different firms, ABB and SIEMENS. Furthermore, documents were studied in order to compliment and increase the understanding of the information provided in the interviews.

    Conclusions: By incorporating the receiver in the analysis we can conclude that the practices applied are not efficient in actually transferring the complete knowledge. Herewith, socialization becomes vital as a complement to these practices in order to also transfer the ‘hidden’ explicit knowledge as well as tacit knowledge that the receiver is in need of. The findings thus demonstrate the importance of taking the nature of knowledge into account when investigating the challenges with current knowledge transfer practices.

  • 14.
    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.

  • 15.
    Thangamani, Manivannan
    et al.
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    Prabaharan, Allen Arun
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    The design of an all-digital VCO-based ADC in a 65nm CMOS technology2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis explores the study and design of an all-digital VCO-based ADC in a 65 nm CMOS technology. As the CMOS process enters the deep submicron region, the voltage-domain-based ADCs begins to suffer in improving their performance due to the use of complex analog components. A promising solution to improve the performance of an ADC is to employ as many as possible digital components in a time-domain-based ADC, where it uses the time resolution of an analog signal rather than the voltage resolution. In comparison, as the CMOS process scales down, the time resolution of an analog signal has found superior than the voltage resolution of an analog signal. In recent years, such time-domain-based ADCs have been taken an immense interest due to its inherent features and their design reasons.

    In this thesis work, the VCO-based ADC design, falls under the category of time-based ADCs which consists of a VCO and an appropriate digital processing circuitry. The employed VCO is used to convert a voltage-based signal into a time signal and thereby it also acts as a time-based quantizer. Then the resulting quantized-time signal is converted into a digital signal by an appropriate digital technique. After different architecture exploration, a conventional VCO-based ADC architecture is implemented in a high-level model to understand the characteristic behaviour of this time-based ADC and then a comprehensive functional schematic-level is designed in reference with the implemented behavioural model using cadence design environment. The performance has been verified using the mixed-levels, of transistor and behavioural-levels due to the greater simulation time of the implemented design.

    ADC’s dynamic performance has been evaluated using various experiments and simulations. Overall, the simulation experiments showed that the design was found to reach an ENOB of 4.9-bit at 572 MHz speed of sample per second, when a 120 MHz analog signal is applied. The achieved peak performance of the design was a SNR of 40 dB, SFDR of 34 dB and an SNDR of 31 dB over a 120 MHz BW at a 1 V supply voltage. Without any complex building blocks, this VCO-based all-digital ADC design provided a key feature of inherent noise shaping property and also found to be well compatible at the deep submicron region.

  • 16.
    Ewert, Per
    Linköping University, Department of Culture and Communication. Linköping University, Faculty of Arts and Sciences.
    Liv i den övergivna trädgården?: Tro och sekularisering i Sverige, speglad mot dominerande teorier om sekulariseringsprocesser2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This master thesis summarizes contemporary theories on secularization processes in the Western world, and compares these with the example of Sweden, which by many scholars is considered to be the most secularized country in the Western world.

    I do this by dividing the most influential theorists in five different groups. In each group I explain how the theorists formulate and motivate their positions. These groups are:

    1) The secularization paradigm, where secularization always accompanies modernization. (Therorists: Steve Bruce and Peter Berger (in the 1960s)

    2) The paradigm basically accepted, but revised to depend on existential security, rather than modernisation as such. (Pippa Norris and Ronald Inglehart)

    3) Religion returned in the public sphere. (José Casanova)

    4) The paradigm completely revised. (Peter Berger (after 1990), David Martin, Charles Taylor)

    5) The post-secular society. (Jürgen Habermas, plus others)

    After this theoretical overview I compile empirical studies on the Swedish example, mainly using the scholars Eva Hamberg and Magnus Hagevi. Apart from these, I mainly use material from Sverigeräkningen – a study of all church attendances in Sweden at one weekend in 1999; plus recurrent studies from the SOM Institute at Gothenburg University as well as from World Values Survey.

    This essay concludes that there is good reason to think that the secularization paradigm is in need of revising. However, there still seems to be some truth in all these theoretical models, essentially because they do not necessarily contradict each other, as much as they deal with the issue from slightly different perspectives.

    The empirical studies of Sweden indicate that our country is indeed highly secularized. The reasons for this may be found partly in all of the theoretical models used in this essay. It is also argued that there may be good explanatory power in the market model, where secularization comes not only due to lack in demand, but also to a weakened supply of religion.

  • 17.
    Lundberg, Peter
    et al.
    Department of Biochemistry, University of Sydney, Australia.
    Roy, Sushmita
    Frick Laboratories, Princeton University, USA.
    Kuchel, Philip W
    Department of Biochemistry, University of Sydney, Australia.
    Immobilization Methods for NMR Studies of Cellular Metabolism: A Practical Guide1994In: ImmunoMethods, ISSN 1058-6687, Vol. 4, no 2, 163-178 p.Article in journal (Refereed)
    Abstract [en]

    Nuclear magnetic resonance (NMR) can be used in a nondestructive manner to study cellular metabolism in intact cell samples such as a suspension of cells. However, many different cell types require a well-regulated medium that includes a buffered pH, as well as a continuous supply of oxygen. A series of methods that have been used for the maintenance of the extracellular conditions involves the immobilization of cells, followed by perfusion of the immobilized cell sample. NMR studies can then be performed for extended periods of time, as well as under sterile conditions. We discuss methodology, with perfused erythrocytes and thymocytes as specific examples.

  • 18.
    Klapuh, Alen
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Svensson, William
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Attitydundersökning av Arconas arbete med bygglogistik2014Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Kostnaden för att bygga hus stiger mer än kostnaden för vanliga konsumtionsprodukter vilket leder till allt dyrare hus. En anledning till detta är att byggprocessen inte hänger med i utvecklingen och att äldre metoder fortfarande används. För att få ett effektivare byggande behöver metoderna därför utvecklas eller nya metoder behöver träda fram, ett exempel på en ny metod är tredjepartslogistik som fler och fler byggföretag använder sig av.

    I denna rapport får du läsa om företaget Arcona AB (Arcona) som samarbetar med logistikföretaget Servistik och som vill undersöka hur arbetarnas attityd är till logistikkonceptet som Arcona använder sig av. Ett projekt, Bryggmästaren, är undersökt i det här arbetet och det är en ombyggnation från kontor till hotell i Stockholm city.

    Anledningen till att Arcona hade intresse av en attitydundersökning av deras koncept var för att de vill få fram information till möjliga förbättringar, för att se om företaget är på rätt spår med konceptet och för att se hur redan gjorda förändringar har påverkat arbetet på byggarbetsplatsen.

    Logistikkonceptet kan sammanfattas enligt följande. Lagbasarna på byggarbetsplatsen beställer material från olika grossister. Det beställda materialet levereras till Servistiks lager och tas emot, inspekteras och lagras. När materialet behövs på byggarbetsplatsen gör lagbasarna avrop till Servistiks lager som i sin tur packar ihop ordern och levererar det till byggarbetsplatsen. Väl framme lastar Servistiks personal av material och distribuerar runt det på byggarbetsplatsen. Leveranstiden från att avropet har gjorts till det att materialet är på plats på bygget är 3 dagar.

    Studien har baserats på intervjuer som har gjorts med Arconas egen personal och med underentreprenörer som har arbetat för Arcona på projektet Bryggmästaren. Åtta stycken intervjuer har gjorts på Arconas platskontor på Bryggmästaren varav en var via telefon. De intervjuade var platschefer, projektchefer, produktionsledare, projektingenjörer, lagbas och underentreprenör.

    Samtliga av respondenterna är positivt inställda till logistikkonceptet som Arcona driver i samarbete med Servistik. De tycker att det är en bra idé och att det låter bra i teorin men de menar också på att ifall det ska fungera så behövs det en viss utveckling eller förändring av konceptet för att det även ska gå att tillämpas i praktiken på ett framgångsrikt sätt. Ett antal förbättringsförslag som dyker upp är:

    • Leveranstiden från lagret behöver minskas för att göra konceptet lite mer flexibelt.
    • Materialkunskapen hos Servistiks personal behöver förbättras så att de har mer koll på vad som exakt kommer in till deras lager.
    • Internetsidan för lagret som visar materialstatus på lagret måste förenklas så att allt ska gå smidigare.
  • 19.
    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.

  • 20.
    Wirell, Viktoria
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Påverkan av förnybar energi på Singapores energisäkerhet2014Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Singapore is one of the most densely populated countries in the world. At the same time the country has an electricity consumption that is among the highest in the world in relation to the population. They have no indigenous energy resources and are therefore dependent on import of fossil fuels to handle their high electricity consumption. Most of their electricity is generated from natural gas which has been imported in pipelines from Malaysia and Indonesia.

    A consequence of Singapore’s heavy dependence on imported fossil fuels is that they have low energy security. Energy security means that the energy supply should be affordable, reliable and adequate. With its heavy dependence on imported fossil fuels, Singapore is exposed to several energy security risks. These energy security risks could result in detrimental consequences for Singapore.

    The environmental benefits of renewable energy are well known, but how renewable energy can contribute to a better energy security is less known. There are several energy security risks related to the use of fossil fuels and renewable energy can therefore, in the countries that have the right conditions, decrease these risks.

    The purpose of this thesis has been to examine if renewable energy can contribute to a more secure electricity supply in Singapore. To do this, theory regarding Singapore, energy security and different renewable energy sources has been collected. The renewable energy sources that have been examined are wind power, hydropower, geothermal energy, solar power and bioenergy. The theoretical background has then been used to analyze the possibility of using renewable energy sources to improve the energy security in Singapore.   

    The conclusion that can be drawn from this study is that some of the renewable energy sources can contribute to a more secure electricity supply in Singapore. Singapore’s geographical conditions are unfavorable for the use of wind power, hydropower and geothermal energy and these energy sources can therefore not be used to improve the energy security in Singapore. The situation regarding solar power and bioenergy is however different and an increase of the electricity production from these sources can contribute to a more secure electricity supply. 

  • 21.
    Wikberg, Sofia
    et al.
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, The Institute of Technology.
    Jerlström Hultqvist, Samuel
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, The Institute of Technology.
    Development of the S&OP process at Seco Tools AB: Aligned with today´s supply chain planning processes 2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background:

    Companies strive to produce as close to customer demand as possible to reduce the cost, inventories, etc. One process that deals with this issue of balancing demand and supply is Sales & Operations Planning (S&OP). Seco Tools is a company with their head-office located in Fagersta, Sweden, which is experiencing high inventory levels and a need of cutting cost. The ongoing project Supply Chain Planning at Seco Tools resulted in the implementation of a new software which enables them to improve demand, inventory, and supply planning. As a result of the improved planning ability, a new S&OP process is developed and in need for improvement.

    Purpose:

    The purpose of this thesis is to evaluate the current S&OP process from the Supply Chain Planning project and to suggest future improvements for Seco Tools AB.

    Research objectives:

    1. Study and describe the current S&OP process at Seco Tools.

    2. Analyse and identify differences in Seco Tools’ S&OP process compared to the literature and a benchmark company.

    3. Perform deeper analyses within financial integration and the use of KPIs in Seco Tools´ S&OP process.

    4. Suggest future improvements to Seco Tools regarding their S&OP process based on the identified differences from research objective 2 and the deeper analysis from research objective 3.

    Method:

    The planning report set the framework for the carrying through of the thesis. A literature study regarding S&OP and a case study performed at Seco Tools regarding their S&OP have been done in parallel. Seco Tools’ S&OP process has been studied and described with the help of interviews, observations, and internal documents. Analysis was made where Seco Tools S&OP was compared to the theoretical S&OP and the S&OP at AstraZeneca. The analysis led to recommendations to Seco Tools regarding improvements in their S&OP process.

    Conclusions:

    Two opportunities for improvement were highlighted during the analysis of Seco Tools S&OP. They were financial integration and the use of cross-functional KPIs covering all the departments that were suggested to be involved in S&OP at Seco Tools. Seco Tools should integrate their finance in the process to compare S&OP against the business plan, and the company’s strategy should be well understood by the participants in S&OP. The knowledge of the company’s strategy together with the right authorities in the process will improve the decision making in Seco Tools’ S&OP. Seco Tools also need to implement an S&OP scorecard with KPIs that covers all departments in the company and the strategy as well. This helps to further develop cross-functionality and to early on make root cause analysis of identified problems. Cross-functionality and KPIs are believed to be general recommendations that all companies can use as well, not only something that Seco Tools can take advantage of. A template for an S&OP scorecard especially for Seco Tools has been made. It contains 16 cross-functional KPIs covering all steps and departments involved in S&OP at Seco Tools.

  • 22.
    Pathapati, Srinivasa Rao
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    All-Digital ADC Design in 65 nm CMOS Technology2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The design of analog and complex mixed-signal circuits in a deep submicron CMOS process technology is a big challenge. This makes it desirable to shift data converter design towards the digital domain. The advantage of using a fully digital ADC design rather than a traditional analog ADC design is that the circuit is defined by an HDL description and automatically synthesized by tools. It offers low power consumption, low silicon area and a fully optimized gate-level circuit that reduces the design costs, etc. The functioning of an all-digital ADC is based on the time domain signal processing approach, which brings a high time resolution obtained by the use of a nanometer CMOS process. An all-digital ADC design is implemented by using a combination of the digital Voltage-Controlled Oscillator (VCO) and a Time-to-Digital Converter (TDC). The VCO converts the amplitude-domain analog signal to a phase-domain time-based signal. In addition, the VCO works as a time based quantizer. The time-based signal from the VCO output is then processed by the TDC quantizer in order to generate the digital code sequences. The fully digital VCO-based ADC has the advantage of superior time resolution. Moreover, the VCO-based ADC offers a first order noise shaping property of its quantization noise.

    This thesis presents the implementation of a VCO-based ADC in STM 65 nm CMOS process technology using digital tools such as ModelSim simulator, Synopsys Design Compiler and Cadence SOC Encounter. The circuit level simulations have been done in Cadence Virtuoso ADE. A multi-phase VCO and multi-bit quantization architecture has been chosen for this 8-bit ADC. The power consumption of the ADC is approximately 630 μW at 1.0 V power supply and the figure of merit is around 410 fJ per conversion step.

  • 23.
    Bohman, Anna
    Umeå Universitet.
    The presence of the Past: a retrospective view of the politics of urban water supply and sanitation in Ghana.2010Conference paper (Refereed)
  • 24.
    Skoglund, Martin
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Mårtensson, Cecilia
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Solar landfills: A study of the concept in a Swedish setting2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The increasing global energy demand, which today is mainly supplied by energy sources with a fossil origin, is a severe threat to the environment and to the security of supply. In order to handle these problems, renewable energy sources are promoted globally as well as nationally in Sweden. Solar photovoltaic (PV) technology is one of the most mature and commercial renewable energy technologies and could play a vital role in phasing out fossil energy sources. In the emerging, promising concept of solar landfills, PV systems are installed on closed landfill sites in order to combine renewable electricity production with resource efficient use of land. In this study the legal, technical and financial aspects concerning a solar landfill project in a Swedish setting were investigated. Additionally, the potential of the concept on a regional level in Sweden was analysed. The methodology used in the study featured literature research, interviews, and a feasibility assessment of a solar landfill project on Visby landfill.

    Regarding the legal aspects linked to a solar landfill project, an inconsistency between Swedish municipalities concerning the need of a building permit for a ground mounted PV system was revealed in the study. While some municipalities demand a building permit, others do not. Additionally, the fact that a closed landfill usually is classified as an environmentally hazardous activity doesn’t result in any need for additional permissions for a PV system installation on a closed landfill. Therefore, such legal aspects are not likely to hinder a solar landfill project to any great extent.

    Considering the technical aspects, the choice of mounting system must be done carefully because of the special conditions which exist on a landfill site; such as ground penetration restrictions and risks of settlement. While a ballasted mounting system can avoid ground penetration, a driven pile mounting system generally features a lighter construction. Furthermore, a fixed tilt mounting system is preferred over a sun tracking mounting system due to the extra weight and sensitivity to settlement which comes with the latter choice. Regarding the choice of PV modules, thin film modules generally feature a lower weight and can therefore be advantageous in comparison with crystalline silicon modules. In the case of Visby landfill, where penetration was preferred to be avoided but where the risk of settlement was considered low, the PV system which was deemed most suitable for the site featured a ballasted fixed tilt mounting system with crystalline silicon PV modules.

    Considering the financial aspects, the study emphasises the importance of using the produced electricity to offset consumed electricity in order to enable a sound investment. This can be done by a wise choice of owning and financing structure where the produced electricity offsets consumed electricity for a large consumer, e.g. an industry or a grocery store, or for a number of residences in a community solar. The economic feasibility also heavily depends on the projects’ possibility to use policy incentives and tax exemptions. The feasibility assessment of Visby landfill showed that the most economically feasible investment was possible by founding a community solar which offsets the members’ consumed electricity. Such an investment would feature a 10 year payback time and an internal rate of return of 8.3 %.

    Finally, the potential of the solar landfill concept on a regional level was identified as significant. In a scenario where the PV system suggested for Visby landfill in the feasibility assessment is installed on all the suitable landfill sites on Gotland, the island has the possibility to produce 22 GWh of electricity from solar landfills, thereby meeting the regional energy goal set for 2020.

  • 25.
    Wali, Naveen
    et al.
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    Radhakrishnan, Balamurali
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    Design of a Time-to-Digital Converter for an All-Digital Phase Locked Loop for the 2-GHz Band2013Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    An all-digital phase locked loop for WiGig systems was implemented. The developedall-digital phase locked loop has a targeted frequency range of 2.1-GHz to2.5-GHz. The all-digital phase locked loop replaces the traditional charge pumpbased analog phase locked loop. The digital nature of the all-digital phase lockedloop system makes it superior to the analog counterpart.There are four main partswhich constitutes the all-digital phase locked loop. The time-to-digital converteris one of the important block in all-digital phase locked loop.

    Several time-to-digital converter architectures were studied and simulated. TheVernier delay based architecture and inverter delay based architecture was designedand evaluated. There architectures provided certain short comings whilethe pseudo-differential time-to-digital converter architecture was chosen, becauseof it’s less occupation of area. Since there exists a relationship between the sizeof the delay cells and it’s time resolution, the pseudo-differential time-to-digitalconverter severed it’s purpose.

    The whole time-to-digital converter system was tested on a 1 V power supply,reference frequency 54-MHz which is also the reference clock Fref , and a feedbackfrequency Fckv 2.1-GHz. The power consumption was found to be around 2.78mW without dynamic clock gating. When the clock gating or bypassing is done,the power consumption is expected to be reduced considerably. The measuredtime-to-digital converter resolution is around 7 ps to 9 ps with a load variation of15 fF. The inherent delay was also found to be 5 ps. The total output noise powerwas found to be -128 dBm.

  • 26.
    Chen, Huijuan
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems.
    Janbakhsh, Setareh
    Linköping University, Department of Management and Engineering, Energy Systems.
    Larsson, Ulf
    university of Gavle.
    Moshfegh, Bahram
    Linköping University, Department of Management and Engineering, Energy Systems.
    Comparisons of ventilation performance of different air supply devicesin in an office environmentManuscript (preprint) (Other academic)
    Abstract [en]

    The aim of this study was to compare ventilation performance of four different air supply devices in an office environment with respect to thermal comfort, ventilation efficiency and energy-saving potential, by performing numerical simulations. The devices have the acronyms: Mixing supply device (MSD), Wall confluent jets supply device (WCJSD), Impinging jet supply device (IJSD) and Displacement supply device (DSD). Comparisons were made under identical set-up conditions, as well as at the same occupied zone temperature of about 24.2°C achieved by adding different heat loads and using different air-flow rates. Energy-saving potential was addressed based on the air-flow rate and the related fan power required for obtaining a similar occupied zone temperature for each device.

     

    Results showed that the IJSD could provide an acceptable thermal environment while removing excess heat more efficiently than the MSD, as it combined the positive effects of both mixing and stratification principles. This benefit also meant that this device required less fan power than the MSD for obtaining equivalent occupant zone temperature. The WCJSD studied in this paper behaved somewhat like the MSD, but caused higher draught discomfort at ankle level because of very high supply velocities, which was might due to small nozzle diameter of the supply device. Further studies are required for the WCJSD to make these conclusions applicable for general conditions. The DSD showed a superior performance on heat removal, air exchange efficiency and energy saving to all other devices, but it had difficulties in providing acceptable vertical temperature gradient between the ankle and head levels for a standing person.

  • 27.
    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.

  • 28.
    Sabigoro, Rocky A.
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, The Institute of Technology.
    Design and Manufacturing of Pneumatic Test Stand for Rod-less Cylinder vertical application2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Within LiU Fluid laboratory there had been a number of hydraulic and pneumatic test stands for research projects and teaching. The effort was needed to do more extension within the field of pneumatics. This thesis was about designing, manufacturing, building and testing the Test Stand for vertical application of pneumatic rodless cylinder. It consisted of three main parts; mechanical structure, pneumatic system and electrical and electronics. The design part focused more on the mechanical structure and pneumatic system. Electrical and electronics had to be installed to facilitate actuation and control of the system after mechanical and pneumatic components were assembled together. The mechanical structure consisted of three main parts; cabinet, carriage and ball balancer. For each part three concepts were generated, evaluated and selected to obtain the most promising concept for further development. The design values were given such that the mechanical structure should have total weight not exceeding 500 kg. The pneumatic system would supply maximum pressure of 8 bar. Upstream pressure was considered to be 6 bar after 25% pressure drop assumed to occur in the system. The mass to be lifted was typically 26 kg moving at a maximum speed of 2 m/s. The whole design process was carried out with safety and design for assembly in mind. The methodologies applied in the design included; identification of need, concept generation, concept selection, CAD modeling and simulation and FE Analysis. Development of concepts involved CAD drawings (3D and 2D) in CATIA V5, calculations and selection of appropriate materials for each component. The pneumatic cylinder applied in this design was a rod-less cylinder (Bosch Rexroth; RTC-DA, MNR: R480628571) with a Piston diameter of 50 mm, stroke of 1.2 m and cushioning stroke of 20 mm. More design information on RTC-DA was not available therefore the information in appendix A was based on series RTC-BV which had close similarities with series RTC-DA. The carriage that moves up and down along the cylinder stroke was designed with a mechanism that imparted disturbance to the system. The mechanism could be set to impart either 100.7 N or 151.02 N disturbance. The design was done with the assumptions that:

     Spring force Fs and extension x were constant

     The system had sonic flow characteristics and critical flow appeared in meter out orifice.

     The air was perfect gas which obeyed equation of state

     Specific heat was constant

     Viscosity was constant

     Flow was one dimensional

     System pressure drop was 25% of the maximum supply pressure.

    Dynamics of the system were estimated analytically and by means of simulation. Corresponding parameter values such as pressure, velocity, flow rate, cushioning stiffness, cushioning force and acceleration were obtained and compared. The product in general conformed to the specifications made prior to the design process.

  • 29.
    Omar, Omar Jaber
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    An On-Chip Memory for Testing of High-Speed Mixed-Signal Circuits2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Mixed-signal processing systems especially data converters can be reliably tested at high frequencies using on-chip testing schemes based on memory. In this thesis, an on-chip testing strategy based on shift registers/memory (2 k bits) has been proposed for digital-to-analog converters (DACs) operating at 5 GHz. The proposed design uses word length of 8 bits in order to test DAC at high speed of 5 GHz. The proposed testing strategy has been designed in standard 65 nm CMOS technology with additional requirement of 1-V supply. This design has been implemented using Cadence IC design environment.

    The additional advantage of the proposed testing strategy is that it requires lower number of I/O pins and avoids the large number of high speed I/O pads. It therefore also solves the problem of the bandwidth limitation that is associated with I/O transmission paths. The design of the on-chip tester based on memory contains no analog block and is implemented entirely in digital domain. In the proposed design, low frequency of 1 MHz has been used outside the chip to load the data into the memory during the write mode. During the read mode, the frequency of 625 MHz is used to read the data from the memory. A multiplexing system is used to reuse the stored data during read mode to test the intended functionality and performance. In order to convert the parallel data into serial data at high frequency at the memory output, serializer has been used. By using the frequencies of 1.25 GHz and 2.5 GHz, the serializer speeds up the data from the lower frequency of 625 MHz to the highest frequency of 5 GHz in order to test DAC at 5 GHz.

  • 30.
    Demircioglu, Sevilay
    et al.
    Linköping University, Department of Management and Engineering, Project management, Innovations and Entrepreneurship . Linköping University, The Institute of Technology.
    Wang, Chenchen
    Linköping University, Department of Management and Engineering, Project management, Innovations and Entrepreneurship . Linköping University, The Institute of Technology.
    Perspectives of Suppliers on Corporate Social Responsibility in Emerging Economies: China and Turkey2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Corporate Social Responsibility is attracting more public attention in business world nowadays. It has evolved well in developed countries while there still remains some CSR issues in emerging economies such as China and Turkey. Thus, when some multi- national enterprises select suppliers in China and Turkey they come with CSR requirements and pressure. In this supplier-buyer context, less study has been carried out from suppliers’ perspective on how they implement the CSR pressure and whether it has positive or negative impact on their relationship with the buyer and impact on themselves.

    In addressing this problem in this particular supplier-buyer environment, the purpose of this study is to explore the perspectives and practices of suppliers regarding CSR in emerging economies like China and Turkey with strong export relationships to companies in developed countries. In order to achieve this purpose, this thesis presents a qualitative study supported by primary data gathered by interviews and secondary data gathered by examining company documents. One Chinese supplier and one Turkish supplier were chosen as two cases in this study. Both have supplier-buyer relationships with the same buyer which has a large role in the textile industry. Interviews were conducted with two suppliers respectively to gain research data.

    The result of the study shows that: (1) CSR is perceived differently by Turkish and Chinese supplier. The Chinese supplier emphasizes their CSR perspectives on only economic and philanthropic levels while the Turkish supplier includes also ethical and legal levels. (2) In supply chains, both suppliers comply with codes of conduct from the buyer and additionally conduct CSR activities voluntarily. Both suppliers focus on philanthropy and community contribution but the Turkish supplier work on environmental friendly products. (3) There is no direct positive impact linked with CSR compliance in terms of supplier-buyer relationship for both suppliers. In other words, requirements on CSR from the buyer do not contribute much to their supply chain relationships. (4) CSR practices bring competitive advantages for both suppliers. Those competitive advantages include innovation capability and positive corporate reputation.

  • 31.
    Fälton, Emelie
    Linköping University, Department for Studies of Social Change and Culture, Department of History, Tourism and Media. Linköping University, Faculty of Arts and Sciences.
    Food and Sustainable Tourism: A study of authenticity and organic food in a customer supply perspective2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The tourism industry has a large impact on the environment’s health and tourists’ behaviours as well as consumption attitudes have an important role. Tourists’ food decisions and engagements in sustainable food could encourage the tourism operators to improve their environmental burdens. This essay investigates the experience of organic food as a part of the sustainable development within the tourism industry. A dualistic authenticity framework has been applied and a method to measure and analyse perceived authenticity has been drawn from the literature. Questionnaires were handed out to the guests and the staff at two Swedish hotels. The results revealed that there are several dimensions in the meeting between the customers and the operators that arrange food experiences in touristic contexts. There is an interest for the question of organic food as a part of the environmental sustainable development, both relative to the contemporary tourism industry and for the future convention to a more sustainable development in the tourism industry. The results presented that organic food is experienced as a central concept that could be a part of and have an important role for the future sustainable development within the tourism industry. An important part of this is the importance to be aware of the meeting between the customers and the operators. Sweden has a potential to accomplish a more sustainable tourism industry in the future, but more research and educations with focus on the subject needs to be made.

  • 32.
    Pettersson, Robert
    Linköping University, Department of Social and Welfare Studies, Social Work. Linköping University, Faculty of Arts and Sciences.
    Villkor. En kvalitativ studie om hur enskilda socialsekreterare resonerar kring att villkora det ekonomiska biståndet.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This paper examines how individual social welfare officers argue about the conditions in foreign aid. The paper is a qualitative interview study there nine social welfare officers from four local governments have been interviewed.

    The results are divided into two areas. First, the client's responsibility over their own lives   and self-determination. These two areas are then analyzed separately.

    The analysis assumes an aletisk hermeneutics where the basis for the attribution of the result is Max Weber's vocation ethics and the more recent research about foreign aid.

    The conclusion of the study was that social workers believe that the client's responsibility for their own self-sufficiency outweighs supply. Financial assistance must be justified in order to be paid regardless of whether this causes rejection of application for financial aid.

  • 33.
    Subramanians, Sankar Saravanan
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Geo-based Mobility Control for Mobile Traffic Simulators2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Most mobile traffic simulators of today depend on the user to supply the mobility behavior of the simulated UEs. This becomes a problem when certain wanted mobility characteristics are to be tested, since the user have to go trough a trial-and-error procedure to come up with the proper mobility behavior. This thesis presents two approaches to mobility control, where the aim is to control UE mobility based on certain mobility characteristics supplied by the end user. The first approach introduces the concept of assigning tasks to UEs, e.g. “cross cell border” or “move to a certain cell”. Furthermore, concepts from control theory are borrowed to control the task assignment process, making it more dynamic and robust. The second approach iteratively calculate movement patterns for the UEs in an area until it finds a movement pattern that has a high probability of satisfying the user’s requested mobility characteristics.

  • 34.
    Dahlström, Patrik
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Geo-based Mobility Control for Mobile Traffic Simulators2013Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Most mobile traffic simulators of today depend on the user to supply the mobility behavior of the simulated UEs. This becomes a problem when certain wanted mobility characteristics are to be tested, since the user have to go trough a trial-and-error procedure to come up with the proper mobility behavior. This thesis presents two approaches to mobility control, where the aim is to control UE mobility based on certain mobility characteristics supplied by the end user.

    The first approach introduces the concept of assigning tasks to UEs, e.g. “cross cell border” or “move to a certain cell”. Furthermore, concepts from control theory are borrowed to control the task assignment process, making it more dynamic and robust.

    The second approach iteratively calculate movement patterns for the UEs in an area until it finds a movement pattern that has a high probability of satisfying the user’s requested mobility characteristics.

    In order to properly evaluate these two approaches a prototype simulator was developed, as well as a virtual network controller to be tested. This test environment simulate a simplified tree network topology.

    Both approaches was tested to control the total number of handovers per second in a simulated area. They both show high accuracy and acceptable precision. Additionally, the task based approach was used to control the cell utilization in a target cell. However, the cell utilization tests showed a lower accuracy and precision than the handover rate control tests.

  • 35.
    Axén, Linus
    et al.
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Fyhrlund, Erik
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Revisionens kostnadsutveckling: En jämförande studie mellan publika bolag och kommuner i Sverige2013Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Introduction The audit fee depends mainly on the relationship between demand and supply. Former studies have found multiple underlying independent variables that affect the audit fee in listed companies and municipalities. The need of a comparative study to analyze the differences in audit fees over time between the two has previously been pointed out.

    Purpose The purpose of the study is to compare and explain the development of audit fees in listed companies and municipalities over time.

    Method The study’s deductive method means that previous research and existing theories have been the foundation from which hypothesis have been derived. A longitudinal study has been performed to measure changes and development over time. Quantitative data has been collected as secondary data.

    Conclusion This study indicates that multiple underlying independent variables explains the audit fees over time. The size of the company, risk and non-audit fees have a significant positive relation with the audit fee. In municipalities the audit fee relates to size, tax base, results and number of mandates.  During the period between 2005 and 2011 the audit fees for listed companies decreased with 0.5 %, whereas the audit fees for municipalities increased with 12.8 %. The difference can largely be explained by differing purposes of the audit and effect of global factors. 

  • 36.
    Hultgren, Elin
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Making renewable electricity a reality: Policies and challenges when transforming Germany´s electricity system2013Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Germany is to undertake a speedy phase-out of nuclear energy and at the same time move into the age of renewable energy. The policy basis for the transformation of the electricity system is the Renewable Energy Sources Act (EEG). The aim of this report is to investigate the transformation of the German electricity system: popularly called the Energiewende. The report will introduce and analyze the Renewable Energy Sources Act as a policy instrument, and how the electricity grid needs to be developed in order to handle the increasing shares of electricity from renewable sources. The history, main regulations, and the success of the EEG will be investigated. Furthermore, the ways in which the EEG needs to be revised will be given attention. The imperfections of today’s electricity grid when implementing a dominating share of renewable electricity, and ways in which Information and Communication Technology can be used in solving those imperfections will be analyzed. The basis for this thesis is a literature study. Since this is a current topic changing frequently, up-to-date research is used as the main reference. The EEG is based on a feed-in tariff system. The main concern when implementing a dominating share of renewable electricity is the fluctuation over time. It is difficult to know how much power will be produced and when. The future challenge of the electricity grid is to keep meeting demand and supply in a secure way. To succeed with the transformation, the EEG not only needs to be revised but a solution to the system stability is also necessary. The EEG is considered a successful policy instrument but what it is missing today is incentives for balancing demand and supply, energy efficiency, and technology innovation. In order to deal with fluctuating sources, the main focus when upgrading the grid should be to improve the forecasting issues. The success of making RES a significant part in electricity generation could become strong proof for the global community that an electricity system based on renewable energy sources is possible.

  • 37.
    Sultan, Zahid
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Agenda 21 As A Tool For Implementing An Improved Traffic Environment And Safety For Developing Countries, A Case Study of Faisalabad, Pakistan2005Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Agenda 21 deals with the sustainability and sustainable transportation strategies are those that can meet the basic mobility needs of all and be sustained into the foreseeable future without destruction of our resource base. In the developing countries transportation is one of the main growing crisis. This crisis is the product of multiple forces, including the rapid pace of urbanisation and a mismatch between the supply of transportation infrastructure, services, and technologies and the mobility needs of the majority of the people, whose incomes are very low. Transportation development policies and investments in most developing countries are focused on encouraging motorization and are indifferent or hostile to low-cost, informal, nonmotorised transportation modes, despite the vital role they play in mobility for lower-income groups.

    My main focus in this study is Asian developing countries, one country – Pakistan – is selected as an example and 3rd largest city in Pakistan named Faisalabad is selected for detailed study. Transportation scenario and problems in this city are closely observed and studied which lead to interesting findings and facts. These include congestion index, loss in working hours, average speed, expenses and commuter satisfaction. Sustainable transportation and environmental problems are also studied for the City of Faisalabad, and recommendations made to improve them. It is finally inferred that there is an urgent need for comprehensive transportation planning, managing Kachi Abadies population, curbing private vehicle use and effectively facilitating the public transportation in the City of Faisalabad.

    Keywords: Sustainable Transportation; Agenda 21; Traffic Safety; Environmental Problem; Developing Countries; Transportation Problems in Faisalabad, Pakistan; Indicators of sustainability;

  • 38.
    Granberg, Helena
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Hellberg, Ingela
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Inleveranser till SAS Bijouterier AB2005Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sven-Axel Svenssons Bijouterier in Söderköping is a company that imports, stores and sell accessories. They have a chain of stores called Glitter but they are also a wholesaler for retailers. They have expanded by opening new shops throughout a period of years. This expansion has caused a delay in the development of the Supply chain. In 1999 there was 14 shops in Sweden and today it is 123 shops in Norden Europe, 2004.

    The goal with this degree thesis has been to find out how the store delivery works today. If the company continues to expand the workflow to the warehouse and the shops will be affected. With simulation the store delivery can be explained and how it affects the work done in the warehouse.

    By creating a model of the real system, we have simulated how the system works today. The model is not an exact copy of the real system, it is a rough simplified image of the reality. The creation of this model makes it possible together with interviews and literature studies to make assumptions about how the delivery pattern could changes for expansions in the future.

    We start with a theoretical background about supply chains and simulation throughout a literature study. We continue with a description of the conditions for this degree thesis. The simulations have been done with a simulation tool called Arena.

    Pretty soon we could se that the pattern of the deliveries can be an obstacle for the company, in their future expansion. The warehouse deliveries works today but not satisfactory, which the company is well aware of. With help of simulation, theory and the knowledge we have got from our education, we have made some assumptions that some changes are necessary to do. In our work there are several proposals on continuing studies that can be done.

  • 39.
    Allström, Andreas
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Korttidsprediktering av restider med Holt-Winters metod2005Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The number of vehicles on our roads is constantly increasing, which results in a lot of problems such as increased noise, pollution and congestion. One solution is to make better use of the capacity of the existing roads. If you can make people use alternative roads, travel at alternative times or use alternative ways of travelling the congestion would decrease, which also would decrease the noise and pollution. One way to influence the drivers is to supply information about, for example, alternative roads or the current traffic situation. If the traffic management centrals had access to reliable predictions of travel times their possibilities to influence the traffic situation would increase, and maybe the worst problems could be avoided. It is when something unexpected occurs that reliable travel time predictions are really needed, but it is also at that time it is most difficult to calculate reliable predictions.

    The purpose with this thesis is to examine a number of methods that are used to predict travel times. Furthermore, one of these methods, Holt-Winters method, has been tested and analysed.

    Prediction of travel times is a complex problem and a reasonable amount of research has been conducted in the subject, with varying success. There are a lot of different methods and models that has been tested and analysed and most of them can be sorted in under one of the following categories: simple statistic analysis, neural networks, regression- and time series analysis and traffic simulation. Which method that is most suitable for predicting travel times depends on how the traffic conditions looks like at the specific road, which data that is available and what the predictions are to be used for.

    The results of the predictions made with Holt-Winters method clearly shows that Holt- Winters method in some cases are just as good as the simple naive predictors it has been compared with, but in most cases the simple naive predictors are better. The results of the predictions with Holt-Winters method has been improved by smoothing the used data before the prediction. To be able to develop Holt-Winters method further, more data is needed, otherwise the model might be adapted to a special case and not be as general as it needs to be. If a larger study is made where there is access to a larger amount of data, it might be possible to adjust the model to the current traffic situation and traffic flow, and maybe also the current weather.

    When it comes to further research a deeper study where the incidents that have occurred and the current traffic flow and travel time are studied would be very interesting.

  • 40.
    Ehn, Louise
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Eklöf, Malin
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    How to Achieve a More Efficient Component Development at St. Jude Medical AB - Survey and Improvement Proposals2005Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The component development within the product development projects at St. Jude Medical AB (SJM AB*) is considered to be inefficient and is in need for improvements. This master thesis was initiated by the Material Supply and Mechanical and Leads Development departments at SJM AB and it has been carried out between January and June, 2005.

    The purpose for this master thesis is to try to find what is negatively affecting the component development at SJM AB and what needs to be done in order to make it more efficient.

    The project consists of an extensive survey phase, where the problem areas negatively affecting the¨component development have been mapped. It started with a brainstorming session, which resulted in a substantial Ishikawa diagram, where many causes to the inefficient component development were defined. The major causes in the Ishikawa diagram were prioritized by employees within the product development projects, in order to receive information about which of these causes that were considered to be the largest bottlenecks.

    In order to visualize the current flow in the component development and to map the problem areas in these flows, workshops were held with three different product development projects. The results from the Ishikawa diagram and the reflections from the workshops were analyzed and they resulted in the continuous work for the remaining time of the project. The continuous work was decided to include the two problem areas; the Internal Component Management and the Suppliers.

    The results delivered by this project are an extensive survey of the problem areas, which negatively affect the component development, a list of improvement proposals for the internal component management and a checklist, which is to be used as an aid when reviewing the design material before

  • 41.
    Thorstensson, Erika
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    GPS based attitude determination2009Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This paper is the result of a masters thesis performed at Linköping University for Saab Bofors Dynamics in Linköping, Sweden.

    Attitude is defined as the orientation of a coordinate frame in reference to another coordinate frame. This is often referred to as three consecutive rotations, called roll, pitch and yaw (or heading). Attitude determination is generally performed using inertial navigation systems composed of gyros and accelerometers. These systems are highly accurate but are very expensive and experience a drift when used for a long period of time.

    The global positioning system, or GPS, was developed by the US military to determine a user’s position, velocity and time. These parameters can all be determined by performing measurements on the GPS satellite signal code that is modulated onto the GPS satellite signal carrier. But the GPS signal can also be use to determine attitude by performing carrier measurements for two or more GPS antennas. When determining the relative position between two antennas, by measuring the phase difference between them, information of the baseline is attained. The calculated baseline will be in a local navigation frame. By rotating it to the known body frame, a rotation matrix known as a direction coordinate matrix, or DCM, will be attained. From this rotation matrix, only two of the three attitude angles can be calculated, since the third rotation is about the baseline’s own axis. Using three or more antennas (two or more baselines), all three attitude angles can be determined from the DCM.

    This thesis work included development of a hardware platform carrying four NovAtel Superstar II GPS receivers. The platform enables serial communications between the receivers and a PC, as well as providing the supply for the receivers and antennas. The attitude determination algorithm was written and tested using a test platform mounted onto a car. The result shows a one degree deviation from an INS reference system in heading and pitch during both static and dynamic tests. The roll angle was not measured during the test drives because only one baseline was locked.

    The GPS based attitude determination system performed well when the baselines were locked, but it requires some improvements for full functionality.

  • 42.
    Engerberg, Paulina
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Martinsson, Patrik
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Analysis of vehicle utilization for Safcor Panalpina2008Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Safcor Panalpina (SAPA) is situated in South Africa and acts as a forwarder as well as a provider of supply chain solutions to clients all over the world. Due to keen competition, it is essential for Safcor Panalpina to continuously improve their business and enhance the efficiency throughout the chain. In order to achieve a higher profit, Safcor Panalpina needs to render a more efficient organization and face the competition from other actors on the market.

    In the present situation, Safcor Panalpina is able to supply clients by their own vehicle fleet or by an outsourced company called MPISI, which is a Black Economical Empowerment (BEE) company. BEE companies are black-owned and are a common used term introduced by the South African government, aimed to help black ownership grow their businesses.

    This thesis is mainly based on the cargo and vehicle flows from two facilities, Phase 1 and 2, to the clients in the Gauteng area, which is a province in South Africa including large cities such as Johannesburg and Pretoria. The facilities are based adjacent to the International Airport of Johannesburg.

    Safcor Panalpina claims that the utilization level for all vehicles is unacceptably low in the current situation. Since SAPA intend to reduce their own fleet, in order to expand the relationship with MPISI, they want to find the right mixture of vehicles economically viable for both parties. The purpose of this thesis is consequently to examine the utilization level of the SAPA and MPISI fleets today and further on find a new optimal fleet of vehicles. Hence, the thesis will investigate the cost perspective of the issue in order to understand what cost savings that can be achieved with this new optimal fleet.

    The chosen method for this thesis is an operation research approach entitled computer simulation, aiming to execute experiments, scenarios and finding the utilization level of each vehicle. The simulation model that is based on the real system, ended up to be a complex depiction of the actual system. Furthermore, experiments and scenarios were performed in order to find better solutions to the problem. However, the cost aspect has as well been taken into consideration in the simulation for all performed scenarios. This facilitates the cost comparisons between the original scenario, in other words the original simulation model, and the executed scenarios. The most cost saving alternative as well as the one with highest utilization level for the vehicles is consequently the chosen alternative in the end.

  • 43.
    Glenros, Marc
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Ståhl, Magnus
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Simulation Games in Quantitative Logistics2010Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Institution of Technology and Science has for several years requested a simulation model in order to promote the KTS-department for potential students, scientists and entrepreneurs. This has resulted in a Master Thesis which consists of two parts. Part one is designed for the potential students and part two for the scientists. For the students the LogiFuel-game will be presented, which is designed in a way that students can recognize and relate to an everyday logistician problem. At the end of the simulation run the player will be evaluated based on the Wagner-algorithm. Even though the player has made the right decisions during the game, he/she will be encouraged to find another optimal solution. In part two which is named SCTemplate, the scientists will be introduced to find a robust optimum in a supply chain. In order to find a robust optimum they are able to align several predetermined parameters’.

    The report describes all of the underlying theories after which the report is divided into two parts. Each part gives the reader an overview of the user interface and model, and is ended with a presentation of the results from the applied methods and/or test runs depending on part. A discussion is conducted about each part in the end of the report and conclusions are drawn. The discussions are at first general but (and then) aimed towards the issues stated at the beginning of the report. In order to keep a wider discussion there is also a part with answers and questions.

    For the laboration a model and a user interface have been created which are capable to demonstrate that an optimum does not need to be robust. This is depicted in graphs showing the systems profit and variance. Thenceforth the Wagner-Whitinalgorithm is implemented in the game in order to evaluate the player´s acting towards an optimal plan. Furthermore the environmental concept has been incorporated by allowing the player to see hers/his generated emissions.

  • 44.
    El Sawy, Omar
    et al.
    USC Marshall School of Business.
    Gosain, Sanjay
    USC Marshall School of Business.
    Malhotra, Arvind
    USC Marshall School of Business.
    Petri, Carl-Johan
    Linköping University, Department of Management and Engineering, Economic Information Systems.
    Integrating Supply Chains and Electronic Commerce in a Unified Europe2000Report (Other academic)
  • 45.
    Magnusson, Mattias
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Using DSP technology to improve sound quality in active speakers2010Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Aditus Science has developed a system to improve the sound quality in speaker systems, using DSP technology. Software developed in MATLAB is being used to make measurements of the speakers via microphones. Based on those results, the parameters for the signal processing in the DSP can be set. A prototype model of the system was used as hardware when the software was developed.

    The system has several analog and digital inputs and outputs over SPDIF, Ethernet, 3.5mm analog stereo plug etcetera. An ADC converts the analog inputs to a digital signal in the format interintegrated circuit sound signal, i2s. The DSP makes signal processing of the digital audio stream to optimize it for the speaker and sends it to the amplifier through a DAC. The digital audio signals are also directly distributed over the Ethernet, the digital output connectors, and to the analog outputs through a DAC. The system is designed to be controlled by the user over a web server or from a front panel on the device.

    The main purpose of the thesis work is to develop the hardware platform to be used for the system. Three different PCBs were designed. One board hosting the digital parts, one the analog parts, and one backplane to connect the other two boards and to provide the power supply.

    The first board with the digital parts includes a DSP, an AVR to be microcontroller, a synthesizer and connectors for the digital inputs and outputs. The DSP is used for the signal processing of the audio signals, and is also used to handle inputs with different sample rates through the internal FARM, flexible audio routing matrix. The AVR micro controller unit is used as the master in the system. It loads the program and parameters into the DSP, ADC/DAC and the synthesizer. It handles the user interface from the front panel, and hosts the server with the user interface over Ethernet. The synthesizer is being used to tune the clock frequency to be able to counteract data drop if the audio stream over Ethernet has a slightly different frequency than the system.

    The board with the analog parts also includes some digital signals from the DSP, and control signals from the AVR to the ADC/DAC. The analog connectors are located in this board and also the input and output networks of operation amplifiers.

    The first part of the work was to make the schematics for the three cards, and the second part to make the layout. Special care was taken to make a system with as good performance as possible. An example of those parts is to carefully design ground planes and power planes to reduce noise and current loops. The placement of the components and the routing of the signals were carefully made to eliminate over hearing and noise introduced between the blocks. It also handles routing of differential pairs and impedance matching.

  • 46.
    Bexell, Jonas
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Bjureus, Erik
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    A study of energy exchange in earth air tubes2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As energy issues today are of great interest the writers of this report have done a research about an alternative to save energy by reducing the cost of preheating the outdoor air.

    By taking the outdoor air to the ventilation system via a pipe buried in the ground, you can preheat the outdoor air, which, in turn, could save energy. By doing this you do not have to bring as much energy to preheat the supply air, to get the desired supply air temperature. The report also explains if the earth air tubes are a good complement to the mechanical ventilation system with a heat exchanger.

    The report begins with describing briefly the history of ventilation systems in use today. It also describes the functions of the system and show to the reader how two of the installation layouts looks like.

    The writers using the project Daggkåpan in Linköping as a basis for the investigation and they also provide an alternative solution to the existing ventilation system.

    This report also demonstrate the factors that come into play to get as much energy exchange as possible, and what problems may arise with this type of complement to the ventilation system with a heat exchanger.

    Trough optimization of the earth air tubes and depending on which energy source is in use, you can actually save energy and by that also money. The factor that proved to bethe most significant for the energy exchange was the pipe length. Other factors such as trench depth, pipe diameter and the air flow has been shown to play a smaller role in how much energy you can save.

    Finally the report ends with the writers own reflections and a discussion based on the results.

  • 47.
    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.   

  • 48.
    Axelsson, Christian
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Janland, Jonas
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    QuaySpeed - effektivare hantering av transportenheter vid hamnterminaler med hjälp av RFID2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    RFID represents, besides bar codes, another way to identify objects. The advantage with RFID, among other things, is that identification can be done without physical or visual contact and with distances of up to several meters. A possible use of RFID could be to speed up the logistic flow in the check in- and boarding processes at ferry ports. The potential earnings this could result in, is for example faster check in, faster leaving/fetching of the transport unit, better track & trace of the transport unit, increased safety and more efficient work on the quay. A number of issues were set up within three main areas: general survey of RFID technology, potential earnings and investment analysis. Besides these main areas, some other interesting issues about alternative identification methods, applications in other contexts and safety was, added to the report. The focus of this case study has nevertheless been to try to point out the potential earnings and benefits with use of RFID technology.

    As basis on order to respond to the issues, a present situation description over the studied system, from terminal – ferry transport – terminal, has been done. In this supply chain, Stena Line and Schenker have been the involved operators. On the basis of this description a case or scenario was set up where the transport units are equipped with RFID transponders. With this scenario as background, combined with discussions with RFID vendors, a cost/revenue analysis was done. Also other issues have been tried to be responded on the basis of this investment analysis combined with the scenario, discussions with RFID-vendors and a theoretical frame of reference.

    The result of the general survey of RFID technology shows, among other thing, that active UHF or SHF transponders is most common within this type of application and that the reading range complies with what is necessary. The transponder identification code does not necessary need to be of the read/write type and can consist of one of the supplier provided identification number. There is however, most often a possibility to use optional identification data, e.g. GS1: s electronic product code, EPC, which could be suitable. The result of the investment analysis shows that the major cost for Stena Line involves the system development part, while costs for hardware are almost insignificant. With continuous revenues through reduced personnel costs, the calculated payoff-time is approximately five years. The major cost for Schenker is hardware as transponders must be installed on trailer and truck. With a transponder price tag of average €20-50 and additional costs for installation, the total cost should become at least a couple of millions SEK. This includes equipping of all transport units that pass through the port of Majnabbe. With this investment, Schenker can benefit by the possibility to a later check in or the possibility to check in 24 hours per day, which can result in more loadings/unloadings and better optimization of the fleet. By identifying both truck and trailer at the quay side area, this will lead to a higher focus on port security issues. This can be seen as an increased service for both Stena Line and Schenker customers, which may result in competitive advantages.With transponder equipped trailers, this also gives the opportunity to increased track & trace applications, apart from the status reporting that today already exists in the ferry terminal. However, to benefit by this to the maximum, it also require RFID-tagging on product- or pallet level, which would lead to complete product transparency for all operators in the supply chain.

    One obstacle to introduce RFID-based check in is the laws and rules within port security, which demands full admittance control. Most likely, there can be found solutions which make automatic check in possible and still lives up to these demands.

  • 49.
    Lohm Isberg, Maximilian
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Olsson, David
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Analysis and performance measurement of construction logistics2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The construction industry is a business with an intense flow of both material and information that require well-functioning logistics in order to not suffer from unnecessarily high costs. Suppliers play a big part regarding the costs of the distribution and handling of material and due to this a construction project’s costs are affected a great deal by the suppliers’ actions. Spinnrocken is a construction project in the town center of Norrköping. The real estate company Fastighets AB L E Lundbergs is the client and the construction company Skanska is contracted as sole constructor for the project. Spinnrocken is planned to be finalized in the summer of 2014 and consists of several rental-apartments and some smaller businesses. Spinnrocken and its central location result in major logistic challenges, because of this Lundbergs and Skanska want to analyze and evaluate the project’s logistic performance. The main purpose of this thesis is to measure the order fulfillment of interior materials, the scaffold material Doka and windows at Spinnrocken by using the so-called perfect order fulfillment measure, as defined in Supply Chain Operations Reference Model. Perfect order fulfillment indicates the delivery performance to the construction site.The combined perfect order fulfillment for the three investigated materials is 18 %. A perfect order fulfillment of 18 % means that only one out of five inspected deliveries to Spinnrocken was considered having no faults at all. The effects of a low perfect order fulfillment are disruptions in the short-term time schedule, delayed operations, additional work and that the work space at the construction site is occupied by unnecessary construction material. The resulting effects thereby affects the project’s economy negatively.

  • 50.
    Nordqvist, Stefan
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Analys av logistikflöde hos Inwall, Katrineholm2008Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Linköping University today runs the research project Industrial housing construction and its effects on the supply chain. The goal with this project is to obtain a better understanding for the development of the construction business for a more industrialized design. This thesis has been carried out as a part of the project, at Inwall in Katrineholm. Inwall is a company that perform bathroom renovations, but with a more industrialized method than the traditional one. The company packs complete “bathroom kits” at a central location and then distributes the kits to different renovation objects. At the location, the renovation process is carried out relatively standardized, in a number of steps in a certain order. For every step, there is an assembly kit with all the parts needed to perform the step. For this method, Inwall has developed a distinctive supply chain. This supply chain and the way Inwall work are the focus of this thesis.

    The purpose with the thesis is not only to generate data to the project Industrial housing construction and its effects on the supply chain but also to serve as a help to the continuous development of Inwall. The purpose will be fulfilled by answering the following questions:

    • What parts/processes should Inwall be focusing at to generate a more efficient supply

    chain?

    • What would the benefits be if a more efficient supply chain was established today?

    • How would a more efficient supply chain effect Inwalls future development?

    The thesis identifies a number of problems in the way which Inwall work today. Proposals of how to solve these problems, and thus obtain a more efficient supply chain, are given in the text. In order to say that a change really were an improvement, there must be a way measure the change. For this reason, parts of the SCOR-model are introduced. The SCOR-modell features a number of metrics, developed to measure different parts and processes of a supply chain.

    Inwalls biggest problem today is that they do not have any IT-based business system to handle the logistic processes of the company. As a result, lot of manual labour is needed and a great responsibility is placed on the people doing it. In some cases, Inwall lacks routines to handle different areas such as failing deliveries etc. If the problems in this thesis were to be solved today, the major profit would be that the amount of work placed on certain people could be reduced but it might not have any great effects on the company’s total profit in a short term basis. But on the other hand, Inwall is counting on a major expansion in a near future, and for this reason some of the problems are needed to be solved or Inwall might need to face the possibility that the logistics could get out of hand.

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