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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.
    Furedal, Lars
    Linköping University, Department of Electrical Engineering. Linköping University, Department of Electrical Engineering.
    Analys, modellering och återskapande av fordonsdynamiska rörelser i tåg2008Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis was to analyse, model and finally generate dynamic vehicular motions in a train. The objective with the analysis was to find important motions for a realistic train experience. The motions from the analysis were then weighted against possibilities for generation in a motion platform.A dynamic motion model was created to model the selected motions. The model was implemented in a simulation environment, more specifically MATLAB/Simulink. The simulation environment was used to simulate the model and to generate outputs to control a motion platform. The motions of the motion platform depended on how the modelled motions were chosen to be generated. The motion model was validated by comparison of results from the model and measured values from a real train.Generation of motions was accomplished by implementation of the model in a motion platform. A virtual test track was constructed and used to test how the implemented model controlled the motion platform. The experience of the test track in the motion platform was evaluated by persons in a cabin mounted on the motion platform.

  • 3.
    Subedi, Yuba Raj
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    The response of ecosystems to an increasingly variable climate2012Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    A wide range of ecological communities ranging from polar terrestrial to tropical marine environments are affectedby global climate change. Over the last century, atmospheric temperature has increased by an average of 0. 60 C andis expected to rise by 1.1- 6.40C over the next 100 years. This rising temperature has increased the intensity andfrequency of weather extremes due to which a large number of species are facing risk of extinction. Studies haveshown that species existing on lower latitude are more sensitive to temperature variability compared to speciesexisting on higher latitude but temperature is increasing rapidly in higher latitude compare to lower latitude. Thisuneven distribution of temperature sensitive species and warming rate has highlighted the need for combined studiesof temperature variability and sensitiveness of species to predict how the ecosystems will respond to increasinglyvariable climate. Using a generalized Rosenzweig-MacArthur model, I explored how temperature variability andsensitivity of species will affect the extinction risks of species and how the connectance and species-richness ofecological communities will govern this response. This study showed that the risk of extinction of species mostlydepends on their sensitivity to temperature deviation from the optimum value and level of temperature variability.Among these two, sensitivity of species to temperature deviation was most prominent factor affecting extinction risk.In this study, connectance did not show any effect on mean extinction risk and time taken by a certain proportion ofspecies to reach pre-defined extinction thresholds. But, species-richness showed some effect on mean extinction riskof species. It was found that risk of extinction of species in species-rich communities was higher compared tospecies-poor communities. Species-rich communities also took shorter time before they lost 1/6 of the species. Thepresent study also suggests a possible tipping point due to increasing temperature variability in near future. In furtherstudies, different sensitivity of species at different trophic levels and the possible evolution of sensitivity of speciesshould also be consider while predicting how ecological communities will respond to changing climate in the longrun.

  • 4.
    Lärka, Anna
    et al.
    Linköping University, Department of Management and Engineering, Business Administration.
    Andersson, Emma
    Linköping University, Department of Management and Engineering, Business Administration.
    Vilken värderingsmodell för verkligt värde redovisar växande skog till en rättvisande bild?: En jämförande studie av DCF, DREM och IHM under en lågkonjunktur.2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Forest is defined by the IASB as a biological asset and should therefore be reported at fair value in listed companies within th EU since 2005. An asset can be reported at fair value in three dfferent means depending on the available market information. If no information exists on which the company can base its valuation a model created by the company can be used which bases the value on assumptions about the market. This third level of valuation implies problems of subjectivity but is nevertheless the level in which most assets are valued. Holmen AB values their forest using a model called DCF which implies a valuation in the third level of the valuation hierarchy. Alternative models have been debated and developed in former articles in order to avoid the problemof subjectivity and create a model that will valuate forest in a higher hierarchy level . The two main models presented are the IHM and the DREM models.

    Purpose: The purpose of the article is to test the three models DCF, IHM and DREM during a recession in order to see which one yields the most true and fair view of the fair value of growing forest.

    Method: The study is based on a comparison and evaluation of the three models valuating forest during a recession. In order to evaluate these Holmen AB has been chosen as a case company. The years 2007 and 2009 have been chosen to enable a comparison of a year of economic growth and a year of recession. Calculations are made based on statistical information and information retrieved from Holmen AB. The models are thereafter evaluated by the criteria set by IASB regarding true and fair view of reported fair value.

    Results: When calculating fair value according to the three models during the years 2007 and 2009 a reduction is obtained by the DREM model, the same is true for the IHM model while the DCF model yields an increase. For companies, the DREM or the DCF model would be preferred. DREM yields the highest estimated value, which would imply high figures in the financial reports. However, the hypothetical assumptions of DREM may create problems of subjectivity. The DCF model gives an increased value during the crisis, something that speaks for its benfit to companies. For stakeholders the DCF model can be argued to be the preferred model since it takes the highest number of variables into account, which is important during a recession. Holmen AB, like some other forest companies, uses a DCF model which gives it a warrant for being reliable. The company´s assertion that the model is reliable combined with the fact that companies during a recession may need a buffer, and should therefore avoid exaggerated fair values, advocates use of the DCF model. All of this combined makes the DCF model the most appropriate model for estimating the fair value of forest in a just manner.

  • 5.
    Ståhl, Sally
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Strokekedjan från början till slut: En etnografisk studie om farlighet och tid i en akut vårdkedja2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    30 000 people in Sweden get a stroke every year. This leads to large personal adaptions as well as high costs for the society. The most efficient treatment, thrombolysis, must be given as soon as possible to have a good effect. At the same time it is very important to find out if the patient has any differential diagnosis that can make the treatment hazardous.

    This study investigates how the course ov events around acute stroke patients take place and important factors for the decision making. The studiy is based on ethnographic field studys on four swedish hospitals. The material is analysed with methods from joint cognitive systems and goal-oriented design. The results show that in spite of different organisation of the course  of events around acute stroke patients are the processes and direct communication most successful for effective spread of information between the processes. The neurologist on call is an important roll who, as well as the rest of the participants in the course of events, balances the decision making between efficiency and thoroughness. The combination of analysis gives results on both system- and individual levels. Possibilites for improvents are given in three categories: logistic, technological and organizational.

  • 6.
    Sahlberg, Jörgen
    Swedish Meteorological and Hydrological Institute.
    Physical modelling of the Akkajaure reservoir2003In: Hydrology and Earth System Sciences, ISSN 1027-5606, E-ISSN 1607-7938, Vol. 7, no 3, 268-282 p.Article in journal (Refereed)
    Abstract [en]

    This paper describes the seasonal temperature development in the Akkajaure reservoir, one of the largest Swedish reservoirs. It lies in the headwaters of the river Luleiilven in northern Sweden; it is 60 km long and 5 km wide with a maximum depth of 92 m. The maximum allowed variation in surface water level is 30 m. The temperature field in the reservoir is important for many biochemical processes. A one-dimensional lake model of the Akkajaure reservoir is developed from a lake model by Sahlberg (1983 and 1988). The dynamic eddy viscosity is calculated by a two equation turbulence model, a k-ε model and the hypolimnic eddy diffusivity formulation which is a function of the stability frequency (Hond o et al., 1993). A comparison between calculated and measured temperature profiles showed a maximum discrepancy of 0.5-1.0oC over the period 1999-2002. Except for a few days in summer, the water temperature is vertically homogeneous. Over that period of years, a weak stratification of temperature occurred on only one to two weeks a year on different dates in July and August. This will have biological consequences.

  • 7.
    Håkansson, Erik
    et al.
    Linköping University, Department of Management and Engineering, Business Administration.
    Åberg, Viktor
    Linköping University, Department of Management and Engineering, Business Administration.
    Measuring Interest Rate Risk in the Treasury Operations of an International Industrial Company Group: A Case Study of Toyota Industries Finance International2012Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: The volatility in the interest rate market have increased during the last decade and this have made interest rate risk management more important for  both financial institutions and non-financial companies with short- and long term financial commitments.

    Objective: The main objective of this thesis is to analyze different ways of measuring interest rate risk in the treasury operations an international industrial company group. Further, the study will also examine the way treasury departments of international industrial company group’s measure interest rate risk and explain why this method have been chosen.

    Method: The research method of the thesis is a case study and a mix of both quantitative and qualitative data has been used to conduct it. The quantitative data have been secondary data received from TIFI’s treasury management software and the qualitative data have been collected through a survey with eight treasury managers from other international industrial company groups.

    Conclusion: The repricing model is suitable because it is straight forward, fairly easy to communicate to management and it focuses on the book value. However, defining relevant time buckets might be difficult. The duration model is a good measurement tool because it can be used in a variety of ways, but a disadvantage is that it focuses on the market value, which might not be appropriate for treasury departments. Stress testing captures the true change in market value, but demands forecasts about future interest rate movements and lacks tools to manage the interest rate risk.

    Treasury departments of international industrial company groups use a variety of measurement methods. The most frequently used methods are duration-, maturity- and Value at Risk models and different kinds of stress tests. The method should not only measure the interest rate risk in a correct way but it should also be easily explained to management and other executives in the company that might not have knowledge about financial economics.

    The main difference between treasury departments and commercial banks is that commercial banks try to earn money on interest rate fluctuations, whereas treasury departments want to minimize the impact of interest rate fluctuations in order to support the company group’s core business.

  • 8.
    Grundström, Petter
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Design and Implementation of an Appraisal Module for Virtual Characters2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the field of artificial intelligence the production of believable emotions are vital to be able to produce believable behavior of virtual agents. This is done with a process called affective appraisal, which means that events and situations are appraised and emotions are produced accordingly. The Artificial Intelligence and Computer Graphics (AICG) lab at Linköpings University has been devel- oping an AI architecture for virtual agents. This architecture had an appraisal module in need of improvement. This M.Sc. thesis had the purpose of doing this.

    Several approaches to affective appraisal are discussed and compared and finally one approach, called the OCC model, is chosen for implementation. This model is suitable for a real-time AI architecture as it is simple, easy to implement and can produce a wide range of emotions. The implementation of the OCC model is described in terms of how its different parts are incorporated into the previously existing AI architecture. Three extensions to the OCC model are also implemented to improve the results: emotional memories, the appraisal of unexpected events and interaction between the produced emotions.

    Finally the implementation is tested and the results of the tests are discussed. It is found that the implementation produces sufficient results for the scope of the thesis and for the requirements of the AI architecture into which it is incorporated. 

  • 9.
    Evangelista, Gianpaolo
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Smith III, Julius Orion
    CCRMA, Stanford University, California, USA.
    Structurally Passive Scattering Element for Modeling Guitar Pluck Action2010In: Proc. of Digital Audio Effect Conf., Graz, Austria, 2010, 10-17 p.Conference paper (Refereed)
    Abstract [en]

    In this paper we propose new models for the plucking interaction of the player with the string for use with digital waveguide simulation of guitar. Unlike the previously presented models, the new models are based on structurally passive scattering junctions,which have the main advantage of being properly scaled for use infixed-point waveguide implementations and of guaranteeing stability independently of the plucking excitation. In a first model we start from the Cuzzucoli-Lombardo equa-tions [1], within the Evangelista-Eckerholm [2] propagation formulation, in order to derive the passive scattering junction by means of bilinear transformation. In a second model we start from equations properly modeling the finger compliance by means of a spring. In a third model we formalize the interaction in terms ofdriving impedances. The model is also extended using nonlinear (feathering) compliance models.

  • 10.
    Adedokun, Adeyemi
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Application of Road Infrastructure Safety Assessment Methods at Intersections2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Traffic safety at intersections is a particularly difficult phenomenon to study, given the fact that accidents occur randomly in time and space thereby making short-term measurement, assessment and comparison difficult. The EU directive 2008/96/EC introduced road infrastructure safety management, which offers a five layer structure for developing safer road infrastructure has been used to develop tools for accident prediction and black spot management analysis which has been applied in this work to assess the safety level of intersections in Norrköping city in Sweden. Accident data history from STRADA (Swedish Traffic Accident Data Acquisition) and the network demand model for Norrköping city were used to model black spots and predict the expected number of accidents at intersections using PTV Visum Safety tool, after STRADA accident classification was restructured and the Swedish accident prediction model (APM) was configured and tested to work within the tool using the model from the Swedish road administration (SRA). The performance of the default (Swiss) and the Swedish APM was compared and identified locations with the high accident records, predicted accident counts and traffic volumes were audited using qualitative assessment checklist from Street-Audit tool. The results from these methods were analysed, validated and compared. This work provides recommendations on the used quantitative and qualitative methods to prevent accident occurrence at the identified locations.

  • 11.
    Häger, Gustav
    Linköping University, Department of Electrical Engineering, Computer Vision.
    Improving Discriminative Correlation Filters for Visual Tracking2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Generic visual tracking is one of the classical problems in computer vision. In this problem, no prior knowledge of the target is available aside from a bounding box in the initial frame of the sequence. The generic visual tracking is a difficult task due to a number of factors such as momentary occlusions, target rotations, changes in target illumination and variations in the target size. In recent years, discriminative correlation filter (DCF) based trackers have shown promising results for visual tracking. These DCF based methods use the Fourier transform to efficiently calculate detection and model updates, allowing significantly higher frame rates than competing methods. However, existing DCF based methods only estimate translation of the object while ignoring changes in size.This thesis investigates the problem of accurately estimating the scale variations within a DCF based framework. A novel scale estimation method is proposed by explicitly constructing translation and scale filters. The proposed scale estimation technique is robust and significantly improve the tracking performance, while operating at real-time. In addition, a comprehensive evaluation of feature representations in a DCF framework is performed. Experiments are performed on the benchmark OTB-2015 dataset, as well as the VOT 2014 dataset. The proposed methods are shown to significantly improve the performance of existing DCF based trackers.

  • 12.
    Antunez de Mayolo, Eduardo
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Study of the Optical Properties of sp2-Hybridized Boron Nitride2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Nitride-based semiconductor materials make it possible to fabricate optoelectronic devices that operate in the whole electromagnetic range, since the band gaps of these compounds can be modified by doping. Among these materials, the sp2-hybridized boron nitride has properties that make it a potential candidate for integration in devices operating in the short-wavelength limit, under harsh environment conditions, due to the strength of the B-N bond.  Nevertheless, this binary compound has been the less studied material among the nitrides, due to the lack of complete control on the growth process.

    This thesis is focused on the study of the optical properties of sp2-hybridized boron nitride grown by hot-wall chemical vapor deposition (CVD) method, at the Department of Physics, Chemistry and Biology, at Linköping University, Sweden. The samples received for this study were grown on c-plane aluminum nitride as the buffer layer, which in turn was grown by nitridation on c- plane oriented sapphire, as the substrate material. The first objective of the research presented in this thesis was the development of a suitable ellipsometry model in a spectral region ranging from the infrared to the ultraviolet zones of the electromagnetic spectrum, with the aim of obtaining in the process optical properties such as the index of refraction, the energy of the fundamental electronic interband transition, the frequencies for the optical vibrational modes of the crystal lattice, as well as their broadenings, and the numerical values of the dielectric constants; and on the other hand, structural parameters such as the layers thicknesses, and examine the possibility of the presence of roughness or porosity on the boron nitride layer, which may affect the optical properties, by incorporating their effects into the model. The determination of these parameters, and their relation with the growth process, is important for the future adequate design of heterostructure-based devices that incorporate this material. In particular, emphasis has been put on the modeling of the polar lattice resonance contributions, with the TO- LO model, by using infrared spectroscopic ellipsometry as the characterization technique to study the phonon behavior, in the aforementioned spectral region, of the boron nitride. On the other hand, spectroscopic ellipsometry in the visible-ultraviolet spectral range was used to study the behavior of the material, by combining a Cauchy model, including an Urbach tail for the absorption edge, and a Lorentz oscillator in order to account for the absorption in the material in the UV zone. This first step on the research project was carried out at Linköping University. 

    The second objective in the research project was to carry out additional studies on the samples received, in order to complement the information provided by the ellipsometry model and to improve the model itself, provided that it was possible. The characterization techniques used were X-ray diffraction, which made it possible to confirm that in fact boron nitride was present in the samples studied, and made it possible to verify the crystalline quality of the aforementioned samples, and in turn relate it to the quality of the ellipsometry spectra previously obtained; the Raman spectroscopy made it possible to further verify and compare the crystalline qualities of the samples received, as well as to obtain the frequency for the Raman active B-N stretching vibration in the basal plane, and to compare this value with that corresponding to the bulk sp2-boron nitride; scanning electron microscopy made it possible to observe the rough surface morphologies of the samples and thus relate them to some of the conclusions derived from the ellipsometry model; and finally cathodoluminescence measurements carried out at low temperature (4 K) allowed to obtain a broad band emission, on all the samples studied, which could be related to native defects inside the boron nitride layers, i.e., boron vacancies. Nevertheless, no trace of a free carrier recombination was observed. Considering that the hexagonal-boron nitride is nowadays considered to be a direct band gap semiconductor, it may be indirectly concluded, in principle, that the dominant phase present in the samples studied was the rhombohedral polytype. Moreover, it can be tentatively concluded that the lack of an observable interband recombination may be due to the indirect band gap nature of the rhombohedral phase of the boron nitride. Spectroscopic ellipsometry does not give a definite answer regarding this issue either, because the samples analyzed were crystalline by nature, thus not being possible to use mathematical expressions for the dielectric function models that incorporate the band gap value as a fitting parameter. Therefore, the nature of the band gap emission in the rhombohedral phase of the boron nitride is still an open research question. On the other hand, luminescent emissions originating from radiative excitonic recombinations were not observed in the cathodoluminescence spectra. This second step of the project was carried out at the Leroy Eyring Center for Solid State Science at Arizona State University.  

  • 13.
    Borgström, Fredrik
    et al.
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics.
    Coyet, Jonas
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics.
    Waste heat recovery system with new thermoelectric materials2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Increasing fuel prices, higher demands on "greener" transports and tougher international emission regulations puts requirements on companies in the automotive industry in improving their vehicle fuel efficiency. On a typical heavy duty Scania truck around 30% of the total fuel energy is wasted through the exhaust system in terms of heat dissipated to the environment. Hence, several investigations and experiments are conducted trying to find ways to utilize this wasted heat in what is called a waste heat recovery (WHR) system. At Scania several techniques within the field of WHR are explored to find the profits that could be made.

    This report will cover a WHR-system based on thermoelectricity, where several new thermoelectric (TE) materials will be investigated to explore their performance. A reference material which is built into modules will be mounted in the exhaust gas stream on a truck to allow for measurements in a dyno cell. To analyze new materials a Simulink model of the WHR-system is established and validated using the dyno cell measurements. By adjusting the model to other thermoelectric material properties and data, the performance of new TE materials can be investigated and compared with today’s reference material.

    From the results of the simulations it was found that most of the investigated TE materials do not show any increased performance compared to the reference material in operating points of daily truck driving. This is due to dominance of relatively low exhaust gas temperatures in average, while most advantages in new high performing TE-materials are seen in higher temperature regions. Still, there are candidates that will be of high interest in the future if nanotechnology manufacturing process is enhanced. By using nanostructures, a quantum well based BiTe material would be capable of recovering 5-6 times more net heat power compared to the reference BiTe material. Another material group that could be of interest are TAGS which in terms of daily driving will increase the power output with pending values between 40-80 %. It is clear that for a diesel truck application, materials with high ZT-values in the lower temperature region (100-350°C) must be developed, and with focus put on exhibiting low thermal conductivity for a wide temperature span.

  • 14.
    Rundqvist, Mikael (Editor)
    Integrationsverket, Analysavdelningen, Norrköping.
    Staten som förebild?: om planer, insatser och utfall i 17 myndigheters arbete med etnisk mångfald2004Report (Other academic)
    Abstract [en]

    The “State as a Role Model” report (Staten som förebild?) deals with the observance of the federal politicians’ regulatory instructions and ethnic diversity work in government authorities. The general idea is that the integration policy be taken seriously, both through giving concrete substance to the objective, of the state serving as a model, when it comes to ethnic diversity, and through examining adherence to this objective. The report focuses on planning, initiatives and outcomes. Working on the basis of the regulations set out by Swedish parliament and Government, the action plans of 17 federal authorities are examines with respect to ethnic diversity, the 17 authorities are asked about their work with diversity, and the outcome in their personnel numbers are mapped. The relationships between planning, initiatives and outcomes are considered, as are the regulatory instructions.

    Of the 17 authorities selected, 15 have drawn up action plans for promoting ethnic diversity. Generally speaking, most of these programs are weak from a content perspective, and the authorities’ diversity work is in need of holistic thinking. Methods for incorporating the integration policy into current day-to-day activities need to be developed.

    One overall impression gained from the interviews with the authorities is that internal work to increase and better utilize the diversity found in Swedish society is perceived as fairly new, and as yet both given relatively little reflection and rather shaky. All of the authorities interviewed need to further develop their diversity work, some more than others.

    When it comes to the outcome in personnel numbers, the percentage of foreign-born individuals working at the 17 authorities is in general considerably lower than the corresponding figure for foreign-born workers otherwise employed in the nation. The fact that foreign-born individuals are generally under-represented in federal administration is reflected in their also being under-represented in different occupations at the 17 authorities, especially with respect to management positions.

    One important observation is that, at most of the authorities surveyed in the study, there was a decline in the total number of employees between the years of 1997 and 2001, although this has not affected foreign-born employees, as is otherwise often the case. The need to hire new people at the 17 authorities during this period, as a whole, has been small. This means that any substantial changes in the composition of personnel through new recruitment have not been possible during the initial years of the integration policy.

    When focus is directed to the local and regional levels, and to the more concrete day-to-day work of the authorities, it becomes clear that an authority’s diversity work is characterized by the nature of its activities. Indepth study on the local and regional levels also shows the importance of organizing the work, as well as the importance of diversity for externally-oriented activities, and that diversity can be perceived as somewhat of a sensitive, new or unfamiliar issue. The closer analyses also show that organizations can follow independent strategies in relation to their plans for ethnic diversity.

    Even if no strong connections can be demonstrated between planning, initiatives and outcomes in the analysis in this report, the Swedish Integration Board feels it is too early to rule out the federal stipulation that authorities use special action plans in their work to promote ethnic diversity. One must remember that the integration policy is a new policy that involves long-range development processes, not all of which are subject to immediate impact. Before the policy is abandoned, the directives on diversity should be implemented in full. One way to make the policy more clear may be to write more specific demands into the directives and budget appropriations to the authorities.

  • 15.
    Bajracharya, Sudeep
    Linköping University, Department of Computer and Information Science.
    Enhanced OpenModelica Python Interface2016Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    OMPython is a Python library for OpenModelica, which provides a Python interface to OpenModelica. This thesis significantly improves OMPython by an enhanced, more powerful and easier to use API. It presents how a user can use the Python interface to simulate and access Modelica models using Python objects. The enhanced OMPython includes the list of functions that have been implemented such as getXXXNames(), getXXXValues(), setXXXValues(), getXXXOptions(), setXXXOptions(), and simulate(), etc. that allow users to interact with Modelica model properties(i.e., model variables) and the output of the OpenModelica compiler and simulator. A few Modelica models are used for demonstrations in order to make it easy for readers to understand. By the way, this thesis does not describe modeling Modelica models or compilation of such models.

  • 16.
    Holm, Rasmus
    Linköping University, Department of Computer and Information Science, Software and Systems.
    Energy-Efficient Mobile Communication with Cached Signal Maps2016Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Data communication over cellular networks is expensive for the mobile device in terms of energy, especially when the received signal strength (RSS) is low. The mobile device needs to amplify its transmission power to compensate for noise leading to an increased energy consumption. This thesis focuses on developing a RSS map for the third generation cellular technology (3G) which can be stored locally at the mobile device, and can be used for avoiding expensive communication in low RSS areas.

    The proposed signal map is created by crowdsourced information collected from several mobile devices. An application is used to collect data in the mobile device of the user and the application periodically sends the information back to the server which computes the total signal map.

    The signal map is composed of three levels of information: RSS information, data rate tests and estimated energy levels. The energy level categorizes the energy consumption of an area into "High", "Medium" or "Low" based on the RSS, data rate test information and an energy model developed from physical power measurements. The coarse categorization provides an estimation of the energy consumption at each location. It is evaluated by collecting data traces on a smartphone at different locations and comparing the measured energy consumption at each location to the energy level categories of the map.

    The RSS prediction is preliminarily evaluated by collecting new data along a path and comparing how well it correlates to the signal map. The evaluation in this thesis shows that with the current collected data there are not enough observations in the map to properly estimate the RSS. However, we believe that with more observations a more accurate evaluation could be done.

  • 17.
    Jarting, Mikael
    et al.
    Linköping University, Department of Management and Engineering, Industrial Economics.
    Persson, Daniel
    Linköping University, Department of Management and Engineering, Industrial Economics.
    Organizational Effects of Using SaaS Systems in SMEs2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    "The cloud" has been a hot subject the last couple of years, and has been considered especially attractive to SMEs due to making it possible for whole information systems to be fully managed by the vendor. This can unburden the customer organization regarding for example large investment costs, hardware and software maintenance, while also adding flexibility and scalability.

    There are three types of service models: infrastructure, platform and software, which dictate what the customer and vendor manages. In Software-as-a-Service (SaaS), which is the focus of this study, a third part manages both the applications and hardware and the users access these resources through the Internet. However, with the usage of SaaS comes several issues for companies to handle and make use of, for example security and mobility.

    This master thesis' aim is to present organizational effects of SaaS usage in SME user companies, by studying customer organizations post implementation. A qualitative comparative study was conducted where we held semi-structured interviews with SME users mainly at their own offices. In total six interviews were conducted at five different companies. At least two years usage experience was a criteria we set to ensure we could retrieve enough data from the companies.

    To fulfill the aim of the study we set out to find common issues affecting SMEs using SaaS systems. Through a pre-study, including literature studies and customer interviews, we determined which of the common issues that could be considered most relevant. Factors taken into consideration was how SaaS specific an issue was and how relevant it is in the post implementation phase, and how much data we were able to retrieve regarding an issue through the interviews. The relevant issues were: price model, vendor relation, frequent updates, mobility and integration. Further, five hypotheses were derived, one for each relevant issue regarding the organizational effects of SaaS usage.

    An analytical model was constructed mainly based on DeLone and McLean's (1992; 2003) original and updated Information System Success Model. The model helped in deriving organizational effects of usage from the different relevant issues. By using the analytical model with interview and literature study material we came up with the findings of this report, as described below.

    The possible price models enables companies to be more flexible with their IT portfolio. Also, it was concluded that the costs of SaaS are based upon usage, which could make it harder to estimate, especially if the usage varies. But it can also be a strength enabling customers to scale their usage as needed.

    In general, the vendor relation between a customer and vendor was not too complex, however with one exception. Our main discovery was that certain factors of SaaS usage affect the degree of experienced vendor lock-in differently. These include the nature of the pricing model, contract binding times and data ownership rights. Further, the level of trust and lock-in level could also affect the customer intention to change system.

    Frequent updates, which are managed by the vendor, reduce time and effort in regards to maintenance performed by customers. However, sometimes the updates could also cause problems when the customer had own configurations.

    The mobility offered by SaaS systems extends organizations ability to work. This includes increased geographical freedom for mainly employees of an organization.

    We found that integration is much more of a general issue for information systems. But in SaaS connection of services are possible and can thus enable further value than each service can on its own. However, integration also causes increased lock-in and system management.

  • 18.
    Rashid, Asim
    et al.
    Department of Mechanical Engineering, Jönköping University, Jönköping, Sweden.
    Kallin, Sara
    Department of Mechanical Engineering, Jönköping University, Jönköping, Sweden.
    Salomonsson, Kent
    Department of Mechanical Engineering, Jönköping University, Jönköping, Sweden.
    Hansbo, Peter
    Department of Mechanical Engineering, Jönköping University, Jönköping, Sweden.
    Simulation of internal mechanical conditions in the lower limb donned in a transtibial prosthetic socketManuscript (preprint) (Other academic)
    Abstract [en]

    This paper investigates the internal mechanical conditions in a transtibial cross-section while in contact with a prosthetic socket. The nite element model considers the nonlinear behaviors of individual soft tissues instead of lumping them together. The contact problem is solved between socket and limb while taking the friction into consideration to determine the contact forces and resultant internal stress-strain in the limb. Simulation results are presented for three dierent socket designs; total contact, total surface-bearing and hydrostatic sockets. Inuence of higher blood pressure on internal mechanical conditions is also explored.

  • 19.
    Ström, Ola
    Linköping University, Department for Studies of Social Change and Culture. Linköping University, Faculty of Medicine and Health Sciences.
    Utvärdering av kuratorers uppfattning om metoden "Förändrande familjesamtal".2014Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of the present study was to describe the professional counselors, in Children and Youth Units at Social services in Örebro, opinion on Magnus Ringborgs model Therapeutic family conversations (FFS), and how useful they perceive it to be.

    Seventeen of the Children and Youth Units twenty-five counselors participated in the evaluation. The counselors were interviewed based on an interview form with pre-defined questions and had opportunity to comment. The focus of the evaluation was the various steps of the method and how important the counselors considered them to be. They were then asked general questions about the method´s usefulness and effectiveness.

    Most counselors had a positive approach to FFS. They considered the method to be easy to apply, facilitated family work, gave structure and streamlined the processing work. Some of the counselors did however perceive the method to have limited use in resource poor- and unmotivated families.

  • 20.
    Eneroth, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Controller Design Enabling Automated and Fuel-Efficient Driving Strategies for Heavy Duty Vehicles in Urban Environments2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The automative industry drives the development towards more autonomous vehicles, this because of both safety and energy conservation reasons. This thesis focuses on solutions to lower the fuel consumption for heavy duty vehicles, which is more and more requested. Both due to increasing fuel costs and to greater environmental awareness. Through extensive simulations with a vehicle model, developed at and provided by Scania CV AB, different driving strategies are evaluated and analysed. This determined how to achieve a low fuel consumption when driving heavy vehicle in an urban environment. The simulations shows that the fuel consumption can be lowered by coasting the vehicle when deceleration and thus minimize the use of the brakes. One should also when possible, select a higher gear to lower the fuel consumption due to engine friction. These strategies are used to develop a controller which lowers the fuel consumption without increasing the trip time for the vehicle. The controller is able to alter the velocity of the vehicle within a reference window which results in both a lower fuel consumption and a shorter trip time for the driving cycle used.

  • 21.
    Poelstra, J. W.
    et al.
    Uppsala University, Sweden.
    Vijay, N.
    Uppsala University, Sweden.
    Hoeppner, M. P.
    Linköping University. Uppsala, Sweden.
    Wolf, J. B. W.
    Uppsala University, Sweden; Science Life Lab, Sweden.
    Transcriptomics of colour patterning and coloration shifts in crows2015In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 24, no 18, 4617-4628 p.Article in journal (Refereed)
    Abstract [en]

    Animal coloration is one of the most conspicuous phenotypic traits in natural populations and has important implications for adaptation and speciation. Changes in coloration can occur over surprisingly short evolutionary timescales, while recurrence of similar colour patterns across large phylogenetic distances is also common. Even though the genetic basis of pigment production is well understood, little is known about the mechanisms regulating colour patterning. In this study, we shed light on the molecular elements regulating regional pigment production in two genetically near-identical crow taxa with striking differences in a eumelanin-based phenotype: black carrion and grey-coated hooded crows. We produced a high-quality genome annotation and analysed transcriptome data from a 2 3 2 design of active melanogenic feather follicles from head (black in both taxa) and torso (black in carrion and grey in hooded crow). Extensive, parallel expression differences between body regions in both taxa, enriched for melanogenesis genes (e.g. ASIP, CORIN, and ALDH6), indicated the presence of cryptic prepatterning also in all-black carrion crows. Meanwhile, colour-specific expression (grey vs. black) was limited to a small number of melanogenesis genes in close association with the central transcription factor MITF (most notably HPGDS, NDP and RASGRF1). We conclude that colour pattern differences between the taxa likely result from an interaction between divergence in upstream elements of the melanogenesis pathway and genes that provide an underlying prepattern across the body through positional information. A model of evolutionary stable prepatterns that can be exposed and masked through simple regulatory changes may explain the phylogenetically independent recurrence of colour patterns that is observed across corvids and many other vertebrate groups.

  • 22.
    Matras, Omolara
    Linköping University, Department of Management and Engineering. Linköping University, Faculty of Arts and Sciences.
    In pursuit of a perfect system: Balancing usability and security in computer system development2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

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

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

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

  • 23.
    Blomgren, Niklas
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems.
    Decoupled Design of Auxiliary Systems for Internal Combustion Engines2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis investigated if decoupled design of the air intake and exhaust systems for four-stroke internal combustion engines is possible. Using the information found design guidelines were set up for the formula student team ELiTH Racing. The literature study revealed that the systems are not uncoupled, and the inuence of exhaust geometry on air intake behavior needed more thorough investigation. Experiments were designed, using a single cylinder engine with simple intake and exhaust geometries. The tests were attempted, but had to be abandoned due to time constraints. Successful tests would have yielded results in the form of pressure measurements, froma Prandtl-tube, in the air intake, and footage of smoke tests. As a secondary task the potential of computer simulations during the design process was investigated, which yielded a suggestion on how to set up a complete reasonable computational model of the systems. This also resulted in that the design guidelines included how to use computer simulations for the design process. Finally a few ways to expand this work are presented.

  • 24.
    Servitja Robert, Maria
    Linköping University, Department of Mathematics, Mathematical Statistics . Linköping University, Faculty of Science & Engineering.
    A First Study on Hidden Markov Models and one Application in Speech Recognition2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Speech is intuitive, fast and easy to generate, but it is hard to index and easy to forget. What is more, listening to speech is slow. Text is easier to store, process and consume, both for computers and for humans, but writing text is slow and requires some intention. In this thesis, we study speech recognition which allows converting speech into text, making it easier both to create and to use information. Our tool of study is Hidden Markov Models which is one of the most important machine learning models in speech and language processing.

    The aim of this thesis is to do a rst study in Hidden Markov Models and understand their importance, particularly in speech recognition. We will go through three fundamental problems that come up naturally with Hidden Markov Models: to compute a likelihood of an observation sequence, to nd an optimal state sequence given an observation sequence and the model, and to adjust the model parameters. A solution to each problem will be given together with an example and the corresponding simulations using MatLab. The main importance lies in the last example, in which a rst approach to speech recognition will be done.

  • 25.
    Blomberg, Rina
    Linköping University, Department of Computer and Information Science.
    CORTICAL PHASE SYNCHRONISATION MEDIATES NATURAL FACE-SPEECH PERCEPTION2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    It is a challenging task for researchers to determine how the brain solves multisensory perception, and the neural mechanisms involved remain subject to theoretical conjecture.  According to a hypothesised cortical model for natural audiovisual stimulation, phase synchronised communications between participating brain regions play a mechanistic role in natural audiovisual perception.  The purpose of this study was to test the hypothesis by investigating oscillatory dynamics from ongoing EEG recordings whilst participants passively viewed ecologically realistic face-speech interactions in film.  Lagged-phase synchronisation measures were computed for conditions of eye-closed rest (REST), speech-only (auditory-only, A), face-only (visual-only, V) and face-speech (audio-visual, AV) stimulation. Statistical contrasts examined AV > REST, AV > A, AV > V and AV-REST > sum(A,V)-REST effects.  Results indicated that cross-communications between the frontal lobes, intraparietal associative areas and primary auditory and occipital cortices are specifically enhanced during natural face-speech perception and that phase synchronisation mediates the functional exchange of information associated with face-speech processing between both sensory and associative regions in both hemispheres.  Furthermore, phase synchronisation between cortical regions was modulated in parallel within multiple frequency bands.  

  • 26.
    Haji Modiri, Shima
    Linköping University, Department of Management and Engineering, Political Science.
    Impacts of Living and Working Conditions on the Health of Immigrants: A Comparative Study on Asylum-Seekers in Germany and the Netherlands2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    During the last several decades, many people, fleeing from disasters or political threats, have applied for asylum in the European countries. Council Directive 2003/9/EC, laying down minimum standards for the reception of asylum-seekers, as well as several other directives, have been developed in the EU in order to ensure fair treatment of the asylum-seekers in all the European countries. However, there are huge differences in the national asylum laws of countries and consequently, the way they treat the asylum-seekers. In this research, the national asylum laws of Germany and the Netherlands are studied and compared, showing that though following the Council Directive, fair or equal treatment of asylum-seekers cannot be guaranteed. In the Netherlands asylum-seekers are granted with a great extent of benefits while in Germany, they are greatly discriminated against. Based on the Social Determinants of Health Model, developed by Dahlgren and Whitehead in 1991, the hypothesis is that the asylum seekers in the Netherlands enjoy better health status than the ones in Germany, because based on the Dutch asylum laws, they have better living and working conditions. In order to confirm or negate this hypothesis, a meta-study of available literature on the health status of asylum-seekers has been done. However, the hypothesis could not be confirmed/ negated due to extreme lack of availability of data in this area.

    By discussing the relationship between life conditions and health of individuals, reviewing current legal instruments regulating asylum in the EU and analyzing the available data on the health status of asylum-seekers, this paper draws the attention to the importance of data and research on these topics and the need for development of practices for collection of such information. Availability of such information can affect future decision and policy makings regarding asylum-seekers and their health and might result in comprehensive reformations in the current national or international legal instruments.

  • 27.
    Sobron, Alejandro
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, Faculty of Science & Engineering.
    Design and Testing of a Flight Control System for Unstable Subscale Aircraft2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The primary objective of this thesis was to study, implement, and test low-cost electronic flight control systems (FCS) in remotely piloted subscale research aircraft with relaxed static longitudinal stability. Even though this implementation was carried out in small, simplified test-bed aircraft, it was designed with the aim of being installed later in more complex demonstrator aircraft such as the Generic Future Fighter concept demonstrator project. The recent boom of the unmanned aircraft market has led to the appearance of numerous electronic FCS designed for small-scale vehicles and even hobbyist-type model aircraft. Therefore, the purpose was not to develop a new FCS from scratch, but rather to take advantage of the available technology and to examine the performance of different commercial off-the-shelf (COTS) low-cost systems in statically unstable aircraft models. Two different systems were integrated, calibrated and tested: a simple, gyroscope-based, single-axis controller, and an advanced flight controller with a complete suite of sensors, including a specifically manufactured angle-of-attack transducer. A flight testing methodology and appropriate flight-test data analysis tools were also developed. The satisfactory results are discussed for different flight control laws, and the controller tuning procedure is described. On the other hand, the different test-bed aircraft were analysed from a theoretical point of view by using common aircraft-design methods and conventional preliminary-design tools. The theoretical models were integrated into a flight dynamics simulator, which was compared with flight-test data obtaining a reasonable qualitative correlation. Possible FCS modifications are discussed and some future implementations are proposed, such as the integration of the angle-of-attack in the control laws.

  • 28.
    Jansson, Emelie
    et al.
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Kapple, Linda
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Vad styr företagens investeringar?En studie om hur förändringar i reporänta, makroekonomiska faktorer samt finansiella indikatorer påverkar investeringar hos svenska företag2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: The central bank of Sweden decided in November 2014 to set the repo rate close to zero. Further they decided to lower the repo rate to -0,10 percent in February 2015. In regard to this, Sweden had a negative repo rate for the first time. According to macroeconomic theory a decrease in the repo rate is performed to stimulate an economy’s investments and consumptions. Whether or not a decrease in interest rates gives greater incentives for firms to invest is a topical subject and an important field of research. In addition to this, the existing research on the Swedish market is insufficient within this field, which gives us further motives to conduct this study.Aim: The purpose of this study is to examine and analyse how changes in the repo rate, macroeconomic factors and financial indicators affects investments of Swedish firms.Completion: The study is conducted with a quantitative approach. A Vector Autoregressive model is created in order to examine the impact of changes in the repo rate, the macroeconomic factors and the financial indicators on firms’ investments. Impulse response functions are estimated to allow a further analysis of these effects. Hence, it is conceivable to examine how one isolated unit-increase in a specific variable affects firms’ investment through several time periods. Furthermore, we estimate three models, one which includes both macroeconomic variables and financial indicators and another which excludes the financial indicators. The last model reflects the repo rate’s impact on investments in two separate time periods.Result: Investments of firms are affected by numerous of factors. One unit-increase of the lending rate, the exchange rate and firms’ expectations of inflation exhibit a negative relation to investments. Furthermore, one unit-increase in GDP-growth tends to increase investments. However, the repo rate has no impact on investments in the first two models. In spite of this, evidence from the third model indicates that the repo rate has a negative impact on investments during the first period.

  • 29.
    Hallmén, Mathias
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Map-Aided GPS Tracking in Urban Areas: Application to Runner Tracking in Sprint Orienteering2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The GPS tracking in sprint orienteering is often a poor supplement to the viewer experience during events taking place in urban areas because of multipath effects. Since the GPS tracking of runners is an important means to making the sport more spectator friendly, it is of interest to make it more accurate.

    In this thesis project, the information provided by the map of a competition is fused with the GPS tracker position measurements and punch time data in a particle filter to create estimates of the runner trajectories. The map is used to create constraints and to predict motion of runners, as well as to create a model of the GPS reliability depending on map position.

    A simple observation model is implemented, using the map to decide if a GPS measurement is reliable or not depending on the distance to the closest building. A rather complex motion model is developed to predict the runner motion within the constraints given by the map.

    The results show that given certain conditions the improvements are vast compared to the traditional GPS tracking. The estimates are bound to possible routes, and they are often very good given that alternative route choices are easily separable. It is however principally difficult to generally improve the tracking using this method. Better measurements or observation models are needed in order to receive a fully satisfying tracking.

  • 30.
    Flaaten, Marcus
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Efficient polygon reduction in Maya2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Reducing the number of vertices in a mesh is a problem that if solved correctly can save the user a lot of time in the entire process of handling the model. Most of the solutions today are focused on reducing the mesh in one big step by running a separate application. The goal of this implementation is to bring the reduction application into the users workspace as a plugin. Many of the modellers in the various computer graphics industries use Autodesk Maya the plugins intention is to create a efficient tool which also give the modellers as much freedom as possible without the need to ever leave Mayas workspace. During the process the possible issues and solutions of creating this tool in Maya will also examined to help introduce the process of creating a tool for Maya. This plugin has the potential to improve on the existing reduction tool in Maya by giving the user more options and a more exact solution.

  • 31.
    Hedström, Marie
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Johansson, Johanna
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Development of a forecast model for public transport trips in smaller cities2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    It has become more important for operators to be able to predict the future number of public transport passengers when consider to place a tender for operating public transport in a city or region, this is due to the new types of operator contracts was introduced quite recently. There are models in use today that can predict this, but they are often time consuming and complex and therefore it can be expensive to perform a forecast. Aside from this, most models in use for Sweden today are adapted for larger cities. Thus, the aim of this thesis is to propose a model that requires minimal input data with a short set up and execution time that can be used to predict a forecast for the public transport system in smaller cities without notably affecting the quality of the result. The developed model is based on a forecast model called LuTrans, which in turn is based on a common method, the four step model. The aim of the model lies within public transportation but it also consider other modes. The input data used by the model mainly consists of socio-economic data, the travel time and distance between all the zones in the network. The model also considers the cost for traveling by car or public transport. The developed model was applied to the Swedish city, Örebro, where a forecast was conducted for a future scenario. It is easily to apply the model to different cities to estimate a forecast for the public transport system. The developed model for the base scenario predicts trips for individual bus lines with an accuracy of 85 % for the city of Örebro. The developed model gave the result that the trips made by public transport in the future scenario of Örebro 2025 will increase annually by 0.94 %. The conclusion is that it is possible to develop a simple model that can be easily applied for a desired city. Although the developed model produced a plausible result for Örebro, further work such as implementation on other cities are required in order to fully evaluate the developed model.

  • 32.
    Eklöw, Mattias
    et al.
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Eriksson, Marcus
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Marknaden för gymnasial utbildning och dess problematik2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When friskolereformen in Sweden was introduced in 1992, the market for secondary education became a competitive market. With new opportunities for schools to pursue secondary education business, the Swedish government hoped that students' preferences could be better met and that the use of resources would be more efficient. Questions answered in this paper is what characterizes the market, which strategies secondary schools uses, effects of asymmetric information and the factors that affect the degree of variation, and what the optimal degree of variation might be.The market for secondary education is mapped based on the SCP-model to get an overview of the market and its characteristics. Salop circle will be applied and detailed discussion about asymmetric information, variety and strategies on the secondary market will be made.In summary, it is noted that the market is characterized by monopolistic competition where it is difficult to predict the secondary schools' incentives. Furthermore, the market is characterized by being fully subsidized in the form of skolpeng with the reason that the positive impact of education on society. The strategies used in the market are marketing, acquisitions, grade inflation, complimentary products and research and development. As there is a lack of information on the market means that students do not make informative choices, which means that it becomes more difficult for individuals to achieve their full potential. Furthermore, the lack of information barriers to entry in the market and the opportunities to compete with quality weakens. The factors that affect the variation in the market were found to be individual preferences, the substitution tendencies, competition and economies of scale.

  • 33.
    Hasan, Mustafa
    et al.
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Nguyen, Felix
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Inflation och den Marginella konsumtionsbenägenheten2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This essay is an econometric study that aims to empirically estimate the relationship between inflation and marginal propensity to consume in Sweden by Error Correction Model (ECM). Two models are developed using the Error Correction Model (ECM) with explanatory variables such as inflation, real interest rates, disposable income, unemployment, and financial assets. We the focus on the relationship between inflation and marginal propensity to consume (MPC). We estimate short and long term dynamic changes in consumption the parameters by ECM models. The theoretical framework of this paper is the Keynesian consumption theory and the Neo-classical consumption theory. We draw conclusions about the relationship between those factors. The results show that there is a statistically significant relationship between inflation and marginal propensity to consume. In the short term, inflation has a positive correlation on the marginal propensity to consume, which means that willingness to consume in the present increases, in order to not lose purchasing power in the inflation increase. In the long term the relationship is negative for the reason that consumers are maximizing utility and distribute their consumption over time in order to consume at the same level for several periods. We find short-term inflation causes 80 percent increase in the MPC; all else being equal. In the long run, over the two periods, inflation causes 24 percent increase initially and then 27 percent decline in the MPC.

  • 34.
    Hammarfrid, Peter
    et al.
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Henningsson, Tom
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Multifaktormodeller på den svenska marknaden - En studie av OMX Stockholm mellan 1996 och 20142015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background:CAPM isn’t in some cases sufficient for explaining expected stock return. Some of CAPM´smispricing errors are well documented and time persistent which has led rise to the usage of correctivefactors. One model that make use of two such corrective factors are the Fama and French three factormodel. It´s been comprehensively tested on the Swedish market where it has shown to achieve higherexplanatory power then the CAPM. In the year of 2012 and 2014 two new Asset Pricing Models wereintroduced, which on the US stock market better captured many of the best known anomalies.Aim:The aim of the study is to test if the Fama and French five factor model as well as the Q-factor model,could contribute to increased explanatory power beyond the three factor model. The study also analyzethe models cyclical sensitivity as well as the individual factor significance.MethodologyThe knowledge building process takes a deductive approach. Existing theories in the form of assetpricing models are tested based on empirical observations in the Swedish market. The research take aquantitative approach and make use of econometric tools in order to ensure statistic accuratesignificance.Result:This research shows no contribution of explanatory power for the Q-factor model, beyond thatachieved from the Fama and French three factor model. The five factor model achieve marginallyhigher explanatory power compared to the tree factor model. The most likely reason why FF5Machieve better results than the Q-factor model is believed to lie in the usage of the factor HML. Theresults also shows that all of the tested models are very instable when used in a short time perspective.Although there are some clear indication on increasing explanatory power in recession compared to inan ongoing bull market.

  • 35.
    Andersson, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Modelling of Cranking Behaviour in Heavy Duty Truck Engines2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In modern heavy duty trucks the battery is a central component. Its traditional role as an energy source for engine cranking has been extended to include powering a number of elec- trical components on the truck, both during driving and during standstill. As a consequence of this it is important to know how much a battery in use has aged and lost in terms of ca- pacity and power output. The difficulty in measuring these factors on a battery in use causes problem, since heavy duty truck batteries are often replaced too early or too late, leading to unnecessary high replacement costs or truck standstill respectively.

    The overall goal of the effort, of which this thesis is a part, is to use a model of the cranking behaviour of a heavy duty truck engine, which depends on the battery condition, to estimate the ageing and wear of a heavy duty truck battery. This thesis proposes a modelling approach to model the components involved in engine cranking.

    In the thesis work, system identification is made of the systems forming part of the cranking of a heavy duty truck engine. These components are the starter battery, the starter motor and its electrical circuit and the internal combustion engine. Measurement data has been provided by Scania AB for the evaluation of the models. The data has been collected from crankings of a heavy duty diesel engine at different temperatures and battery charge levels. For every cranking lapse the battery voltage and current have been measured as well as the engine rotational speed.

    A starter battery model is developed and evaluated. The resulting battery model is then incorporated into two different engine cranking models, Model 1 and Model 2, including a starter motor model and an internal combustion engine model apart form the battery model. The two cranking models differ in several aspects and their differences and resulting evalu- ations are discussed.

    The battery model is concluded to be sufficiently accurate during model verification, however the two cranking models are not. Model 2 is verified as more correct in in its output than Model 1, but neither is sufficiently accurate for their purpose. The conclusion is drawn that the modelling approach is sound but development of Model 2 is needed before the model can be used in model-based condition estimation. 

  • 36.
    Gustavsson, Johan
    Linköping University, Department of Computer and Information Science, Software and Systems. Zenterio.
    A Comparative Study of Automated Test Explorers2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With modern computer systems becoming more and more complicated, theimportance of rigorous testing to ensure the quality of the product increases.This, however, means that the cost to perform tests also increases. In orderto address this problem, a lot of research has been conducted during thelast years to find a more automated way of testing software systems. Inthis thesis, different algorithms to automatically explore and test a systemhave been implemented and evaluated. In addition to this, a second setof algorithms have been implemented with the objective to isolate whichinteractions with the system were responsible for a failure. These algorithmswere also evaluated and compared against each other. In the first evaluationtwo explorers, which I called DeBruijn and LStarExplorer, were consideredsuperior to the other. The first used a DeBruijn sequence to brute forcea solution while the second used the L*-algorithm to build an FSM overthe system under test. This FSM could then be used to provide a moreaccurate description for when the failure occurred. The result from thesecond evaluation were two reducers which both tried to recreate a failureby first applying interactions performed just before the failure occurred. Ifthis was not successful, they tried interactions further and further away, untilthe failure was triggered. In addition to this, the thesis contains descriptionsabout the framework used to run the different strategies.

  • 37.
    Dasander, Carolin
    Linköping University, Department of Social and Welfare Studies.
    En myndighet i förändring: En fallstudie om Lean på Migrationsverkets mottagningsenhet.2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to illustrate how the business philosophy Lean, originating from the Japanese manufacturing industry, has been transferred to The Swedish Migration Agency. In addition to this, I will also look at how the management philosophy New Public Management (NPM) has been introduced in The Swedish Migration Agency´s discourse.

     

    The Swedish Migration Agency is an authority of change and 2015 has so far been an eventful year marked by record high refugee flow in combination with the new organizational structure, alongside with mass recruitment in the organization.

     

    The Lean model gaining ground can be seen as a paradigm shift and a shift from a democratic discourse to a NPM-discourse, where the state had previously been characterized by traditional bureaucracy, but now focuses on efficiency and management by objectives. This development creates a neoliberal effect on the Swedish welfare society, where citizens gradually transforms into consumers.

  • 38.
    Rapp, Joel
    et al.
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University.
    Turesson, Jonatan
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University.
    Hydrostatic transmission in wind turbines: Development of test platform2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis project is a part of a larger project with the goal of develop-ing a drivetrain, utilizing a hydrostatic transmission, for horizontal axis mid-sizewind turbines. Some of the benefits from using a hydrostatic transmission are thata variable speed operation is possible without the use of a frequency converter,the generator may be placed on the ground and thus reduce weight in the nacelleand also using hydraulic components can increase lifetime and robustness of thesystem. The thesis work is a part of the second step towards this goal, whichcontains constructing a test platform of the concept.

    The test platform is being built at the Laboratory of Hydraulic and PneumaticSystems (LASHIP) in Florianópolis, Brazil, where also the master thesis projecthas been conducted. Two companies are involved in the construction of the plat-form, Parker Hannifin and Reivax. Parker Hannifin is a multinational diversifiedmanufacturer of motion and control technologies and systems. Reivax developtechnologies for control systems and automation applied in Hydroelectric, Ther-moelectric and Nuclear power plants.

    The project was performed during the period of February to August 2015 andgoverns dimensioning and selection of hydraulic components for the test platform,development of simulation model in AMESim, evaluation of control strategies andalso a dynamic analysis of the system.

    Dimensioning the platform resulted in a drivetrain with an output power of28 kW. Standard hydraulic components with high efficiencies where selected fromParker’s product portfolio. These components were then modeled in AMESimwhere simulations of the whole system could be performed. Control strategieswere tested and results showed that the best performance is reached when usinga regulator that is able to compensate for pressure changes in the system. Re-sults also indicated that the hydrostatic transmission can perform very well as areplacement of frequency converters, in terms of stable frequency output of a vari-able wind turbine. The dynamic analysis showed that the parameter that sets themain characteristics of the system is the aerodynamic rotor with its large inertia.

  • 39.
    Ödling, Mattias
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    How Provider Value is Perceived in regards to Integrated Product Service Offerings and why: A case study2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As companies grow larger and become more international, it is likely that it comes to a point where it would be cheaper to produce on site, or at least have distribution centers, rather than having a centralized production that requires long range shipping. As this occurs, there is a wide range of challenges that the company must face, however these challenges are by now well documented and while not to be underestimated and called “easy” it is nothing new as a wide range of companies have done it before. One aspect that however is less known is the influence that external differences has, in other words factors that would produce a differing result even with the exact same internal setup, on the perceived aspects (referred to as Values in this work) from the providers point of view. In particular what is interesting is the perceived positive impacts above expectations that is gained from having external differences. To be able to better understand and quantify this impact the term “Provider Value” has been created and is being researched towards understanding what Values exist and how they are being affected.Provider Value (PV) is a cutting edge concept within eco-design research that this work is based on and in particular ProVa – Provider Value Evaluation for Integrated Product Service Offerings (Matschewsky et al. 2015) is the latest step to date towards creating the tools needed to increase the utilization, and reap the benefits, of PVs. Another interesting and relevant aspect to PV is how Product/Service System (PSS) could be an essential part in paving a new way of avoiding increased environmental impact while having economic growth. This is done by adding services on top of already existing products (Sakao et al. 2009).To find out more about what kind of external factors that might be behind the differences a case study was conducted, interviewing employees at two companies within one concern in Sweden and Japan. The results of this work indicates that if the company want its PVs to remain the same the main obstacle is external economic differences. In this particular study it is also clear that differences in business model and company structure has a big impact. With all the discussion regarding environment it was on a surprisingly low level of interest at both companies and what mattered was that the products cleared the minimum requirements, nothing more, as “any additional return is hard to estimate”. If PV keeps growing and tools are made to assist, this could not only help simplify the transitioning to other countries and help utilizing existing Values from the start, it could also increase the utilization in general, in particularly in regards to the Environment.

  • 40.
    Booson, Alexander
    et al.
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Swahn, Lowe
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Popularitet på aktiemarknaden: En undersökning av aktiers popularitets effekt på risk och avkastning2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: Over the past few decades it has been generally accepted that market premiums come with an associated level of risk. Even the most widely used pricing model today, CAPM, leans on this assumption. In an article written by Ibbotson and Idzorek (2014) this assumption is challenged as the main driver of market premiums and returns. The article contains evidence that relatively high returns have been earned through buying less  popular stocks on the U.S. stock market. Surprisingly the risk-return dimension exhibited an inverse relationship. This evidence from the U.S. stock market motivates us to investigate to what extent this effect can also be seen on the Swedish stock market.

    Aim: The aim of this thesis is to identify and analyze the effect of a stock`s popularity on the risk and return.

    Completion: In this quantitative study, share turnover and market capitalization have been used as approximations for popularity. The effects of stocks popularity on risk and return have been are examined by evaluating the performance of portfolios when categorizing the stocks by share turnover and market capitalization. The statistical relationship between popularity and return is analyzed using regression analysis. This study has both studied the effect of last year's popularity, as well as the effect of the popularity of the same year.

    Conclusion: When various approximations for the popularity dimension are studied and compared, this study shows no marked effect of stock`s popularity from the previous year on risk and return. The study finds no statistically significant relationship between the previous year ́s popularity and return. However, there is a positive statistically correlation between popularity and return when measured during the same year as when the popularity was measured. In addition, the results establish evidence for the stock turnover as a good measure of popularity.

  • 41.
    Johansson, Niklas
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Efficient Simulation of the Deutsch-Jozsa Algorithm2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    We provide a framework wherein one can simulate the Deutsch-Jozsa quantum algorithm on a regular computer within polynomial time, and with linear memory consumption. Under certain reasonable assumptions the simulation solves the problem with a bounded error of probability with only one function evaluation, which is comparable with the efficiency of the quantum algorithm. The provided framework lies within a slight extension of the toy model purposed by Robert W. Spekkens Phys. Rev. A 75 (2007), and consists of transformations that are reminiscent of transformations in quantum mechanics.

  • 42.
    Fält, Viktor
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Strategies to effectively integrate a 3D model of a building in a software systems for real-time visualization2015Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    En unik presentation av en byggnad modellerad som en 3D-modell kan göras med avancerad teknik. Ett sätt att presentera den på är till exempel på en 360-graders immersiv display, där möjligheten att interaktivt ”gå runt i” 3D-modellen erbjuds med hjälp av sex stycken projektorer som samverkar. Detta presentationssätt har Norrköpings visualiseringscenter som mål att erbjuda. För att göra detta krävs det att man tar hjälp av programvaror för realtidsvisualisering. En av dessa kan vara Unity 5 som är en spelmotor. Målet med examensarbetet är att hitta tillvägagångssätt och strategier för att effektiv integrera en 3D-modell av en byggnad i Unity 5. För att göra detta så tillämpas en teknisk undersökning med observationer som metod. Denna undersökning visar att en integration för att återspegla modellen modellerad i Revit till programvarusystem för realtidsvisualisering kan utföras. Återspeglingen är ett faktum som får tas i relation till integrationens helhet och kan inte bli exakt. Frågan är om den kan utföras effektivt nog för vad som Norrköpings visualiseringscenter vill kunna erbjuda. Vilket den kan om modellens uppbyggnad, storlek och projektbegränsningar är rimliga i förhållande till tid och kostnad. Det är dessa aspekter som avgör om integrationen kan utföras effektivt. Kunskap om hur integrationen ska gå till med alla materialinställningar som behövs är dessutom en väsentlig faktor.

  • 43.
    Bjarnle, Johan
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Holmström, Elias
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Implementation and Evaluation of Historical Consistent Neural Networks Using Parallel Computing2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Forecasting the stock market is well-known to be a very complex and difficult task, and even by many considered to be impossible. The new model, emph{Historical Consistent Neural Networks} (HCNN), has recently been successfully applied for prediction and risk estimation on the energy markets. HCNN is developed by Dr. Hans Georg Zimmermann, Siemens AG, Corporate Technology Dpt., Munich, and implemented in the SENN (Simulation Environment for Neural Network) package, distributed by Siemens. The evalution is made by tests on a large database of historical price data for global indicies, currencies, commodities and interest rates. Tests have been done, using the Linux version of the SENN package, provided by Dr. Zimmermann and his research team. This thesis takes on the task given by Eturn Fonder AB, to develop a sound basis for evaluating and using HCNN, in a fast and easy manner. An important part of our work has been to develop a rapid and improved implementation of HCNN, as an interactive software package. Our approach has been to take advantage of the parallelization capabilities of the graphics card, using the CUDA library together with an intuitive and flexible interface for HCNN built in MATLAB. We can show that the computational power of our CUDA implementation (using a cheap graphics device), compared to SENN, is about 33 times faster. With our new optimized implementation of HCNN, we have been able to test the model on large data sets, consisting of multidimensional financial time series. We present the results with respect to some common statistical measures, evaluates the prediction qualities and performance of HCNN, and give our analysis of how to move forward and do further testing.

  • 44.
    Joelsson, Andreas
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Ohlsson, Jonathan
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Indoor propagation modelling at microwave frequencies in a server environment2015Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Link¨oping site is the first of Ericsson’s three information and communication technology centres. This facility will house the company’s complete portfolio and use the latest cloud technology in order to enable the research and development engineers to more efficiently test and develop new technologies. In the test lab environment there is a high capacity microwave telecommunication system called MINI-LINK. These systems operate at much higher frequencies than more traditional telecommunication systems. In the test lab these systems are communicating with a cable interface instead of its intended air interface. The purpose of this thesis is to evaluate the potential leakage of this system in the test lab environment.

    The evaluation of the leakage in the test lab is done by developing an empirical path loss model for the desired frequencies used by the equipment in the test lab. This model is later implemented in a leakage simulation tool designed in Matlab, which simulates and displays the leakage power in a 2D plane. This report mainly focuses on the process of determining the constants and the implementation of the path loss model.

  • 45.
    Henriksson, Johan
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Face detection for selective polygon reduction of humanoid meshes2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Automatic mesh optimization algorithms suffer from the problem that humans are not uniformly sensitive to changes on different parts of the body. This is a problem because when a mesh optimization algorithm typically measures errors caused by triangle reductions, the errors are strictly geometrical, and an error of a certain magnitude on the thigh of a 3D model will be perceived by a human as less of an error than one of equal geometrical significance introduced on the face. The partial solution to this problem proposed in this paper consists of detecting the faces of the 3D assets to be optimized using conventional, existing 2D face detection algorithms, and then using this information to selectively and automatically preserve the faces of 3D assets that are to be optimized, leading to a smaller perceived error in the optimized model, albeit not necessarily a smaller geometrical error. This is done by generating a set of per-vertex weights that are used to scale the errors measured by the reduction algorithm, hence preserving areas with higher weights. The final optimized meshes produced by using this method is found to be subjectively closer to the original 3D asset than their non-weighed counterparts, and if the input meshes conform to certain criteria this method is well suited for inclusion in a fully automatic mesh decimation pipeline

  • 46.
    Fonseka, Christopher
    et al.
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Ny, Jesper
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Hur kan incitament hantera interorganisatoriska osäkerheter i en leverantörsrelation?: En fallstudie av AstraZeneca2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: After a literature review we discovered that research about supplierrelationships exists, but that the connection between incentives, interorganizational controlssystems and uncertainties is absent. To study this connection is therefore in our interestbecause it contributes to academic research in the field of interorganizational controlsystems. This is because incentives bring a new perspective to the connection betweeninterorganizational control systems and uncertainties.

    Purpose: The purpose of this study is to describe which interorganizational uncertaintiesa buyer experiences within a supplier relationship and how the uncertainties affect thesupplier relationship. The purpose of the study is also to describe how a buyer can handleinterorganizational uncertainties with incentives.

    Completion: A comparative analysis of the supplier relationships to Arcadia, Nexus andValhalla was achieved by combining a theoretical uncertainty model and qualitativeinterviews.

    Conclusions: The study confirms that there are four different types of uncertainties in asupplier relationship, which are task uncertainty, task interdependency, environmentaluncertainties and relational stability. The effect of the uncertainties in a relationship isderived in a theoretical uncertainty model and is also empirically confirmed. The studyfurthermore identifies incentives that handle uncertainties the buyer experiences in asupplier relationship.

  • 47.
    Bodin, Erik
    et al.
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, Faculty of Science & Engineering.
    Stenholm, Fanny
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, Faculty of Science & Engineering.
    Modelling & Control of a 3DOF Helicopter2015Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The scope of this report is the development of a mathematical model and a control system for a three degrees of freedom (3DOF) helicopter rig. This 3DOF-system offers a good simplification of a real world tandem helicopter for evaluating performanceof different automatic control principles.

    A mathematical model of the system is developed using free-body diagrams. This mathematical model is then linearized and a controller is developed by decoupling the system. Due to model imperfections external disturbances and similar effects integral action is added as well as feed-forward compensation to reduce nonlinear effects.

    After the controller has been decoupled the two different controllers are tuned. The Linear-Quadratic Regulator, described in section 3.6, is used for selectingstate-feedback gains. Due to the highly nonlinear nature of the system an Extended Kalman Filter is developed to estimate unmeasurable states.

    The model and controller is then implemented on the actual rig and evaluated. The results displayed that the elevation controller had good performance. The travel controller also showed good performance but not as good as the elevation controller.

    The main goal of this thesis was to develop a controller for the 3DOF helicopter system. The results clearly show that an LQR-controller is able to successfully control a system like this with decent performance characteristics despite the highly nonlinear system.

  • 48.
    Seidu, Mohammed Nazib
    Linköping University, Department of Computer and Information Science.
    Predicting Bankruptcy Risk: A Gaussian Process Classifciation Model2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis develops a Gaussian processes model for bankruptcy risk classification and prediction in a Bayesian framework. Gaussian processes and linear logistic models are discriminative methods used for classification and prediction purposes. The Gaussian processes model is a much more flexible model than the linear logistic model with smoothness encoded in the kernel with the potential to improve the modeling of the highly nonlinear relationships between accounting ratios and bankruptcy risk.

    We compare the linear logistic regression with the Gaussian process classification model in the context of bankruptcy prediction. The posterior distributions of the GPs are non-Gaussian, and we investigate the effectiveness of the Laplace approximation and the expectation propagation approximation across several different kernels for the Gaussian process. The approximate methods are compared to the gold standard of Markov Chain Monte Carlo (MCMC) sampling from the posterior.

    The dataset is an unbalanced panel consisting of 21846 yearly observations for about 2000 corporate firms in Sweden recorded between 1991−2008. We used 5000 observations to train the models and the rest for evaluating the predictions. We find that the choice of covariance kernel affects the GP model’s performance and we find support for the squared exponential covariance function (SEXP) as an optimal kernel.

    The empirical evidence suggests that a multivariate Gaussian processes classifier with squared exponential kernel can effectively improve bankruptcy risk prediction with high accuracy (90.19 percent) compared to the linear logistic model (83.25 percent).

  • 49.
    Wallstedt, Lennart
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. 630307-3354.
    Hassel (Corylus avellana) som indikator på markanvändningshistorik2015Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Hazel (Corylus avellana L.) is a common feature of meadows and pastures where it can grow in large populations and become very old. Is it possible to use the size of hazel stools for age determination and is it possible to use the size distribution of a population to provide information about how the land has been used? Hazel populations on ground where the lake-water level had been lowered, has been studied to validate an already developed growth model of hazel clones. Different hazel populations, on wooded meadows affected by mowing or grazing or overgrown meadows, were studied to evaluate the method utilizing hazel as land use indicator. The growth model was used to compare the size distributions of hazel populations with historical periods, which has been important for changes in agriculture or demography. The results show that the current growth model needs to be refined, but the method itself with a growth model based on the circumference of hazel bushes seems feasible. Additional studies about the influence of, for example, soils of different fertility are needed. The results also show that the size distribution in a population depends on how much meadows have been affected by mowing or grazing and that areas with similar land use have similar size distribution. Finally, some examples are reported about how a growth model can be used to compare historical periods of changes in agriculture, for example reduced livestock, with variations of the size distribution in a hazel population.

  • 50.
    Forsman, Madeleine
    et al.
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Wiström, Kristin
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Experter i revisionsprocessen: Hur upplever revisorn att revisionskvaliteten påverkas?2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background and Problem: Accountants have become dependent with using experts in theirwork because of the complexity that has occurred around both accountingand auditing. It is the auditor that decides when an expertshould be included and how great of impact the experts work willhave on the audit. Meanwhile the auditor’s duty is to deliver qualityassured information to stakeholders and it is the auditor that willdecide when adequate audit quality is achieved. The question ishow the auditor experiences the influence on audit quality whenthey include experts in their work?

    Purpose: The purpose of the study is to explain how the auditors experiencethe influence on audit quality when they include experts in theirwork.

    Method: This study has mainly a quantitative method where surveys havebeen sent to auditors to obtain answers to the study’s purpose. Toget a deeper understanding of the experts work has a qualitativefeasibility study with interviews been conducted.

    Conclusion: Our results indicate that auditors feel that audit quality will behigher when the experts are used in the audit. The results from ourfirst regression model suggests that when the experts get moreleeway/influence auditors experience that audit the quality will behigher. Audit quality is also affected slightly by the extent towhich auditors are taking the help of experts. Accountants whotake the help of experts to a greater extent perceive that auditquality will be higher. The result from our second regression modelindicates that it’s only the expert's influence that leads to higheraudit quality. Our results indicate that, according to auditors isworth spending time and resources on experts when they contributeto higher quality audits.

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