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  • 1.
    Wiklund, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Kretsloppsanpassat energi- och avloppssystem för ett fritidshus2013Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    En genomsnittlig villa på 149 m² i Sverige med direktverkande el för uppvärmning använder ungefär 23980 kWh el per år. Av detta så står uppvärmningen för ungefär 13480 kWh, eller 90,5 kWh/m². Att minska denna energianvändning är gynnsamt både för miljönoch ekonomin.Genom att utrusta ett hus på ungefär 161 m² med energisnål utrustning, luftvärmepumpar, bra isolering, ett effektivt ventilationssystem och solfångare så kan elanvändningenminskas med ungefär 20170 kWh per år, till en användning på ungefär 4900 kWh per år.Vad uppvärmningen beträffar så är detta en minskning från 14570 kWh (90,5kWh/m²) till ungefär 1400 kWh (9,4 kWh/m²). Skulle huset användas som ett fritidshus under åtta månader per år, så skulle elanvändningen bara hamna på ungefär 2500 kWh, vilket iförhållande till den uppskattade energianvändningen på 10035 kWh för motsvarande tidsperiod innebär en minskning på ungefär 7535 kWh. För värmens del så innebär detta en minskning från 3035 kWh (18,85 kWh/m²) till ungefär 256 kWh (1,6 kWh/m²).Varmvatten kan fås från solfångare. Om huset används under de åtta soligaste månaderna så skulle varmvattenbehovet nästan helt täckas med fyra solfångare av typ DAC-H 150L. Det som inte täcks av solfångarna kan en elektrisk varmvattenberedare täcka.För att ta tillvara på näringsämnena i toalettavfallet så kan en separationstoalett användas.En bonde som tar hand om toalettavfallet och använder det som gödning skulle tjäna ungefär 330 kr för varje person vars närsalter bonden omhändertar. Om skörden är god så motsvarar detta 9900 kr/ha. Det är mer än vad själva skörden ger.För att rena vattnet från bad, dusch och tvätt (BDT-vatten) så kan en IN-DRÄN infiltrationsbädd användas. Denna kommer att rena BDT-vattnet från närsalter, i de flesta avseenden bättre än ett kommunalt reningsverk. Om träd planteras runt biobädden så kande även rena vattnet från de närsalter som inte renas av biobädden, som annars skulle kunna orsaka övergödning.En stor del av elbehovet skulle kunna täckas med ett solcellssystem. Med ett system med 36 st solpaneler av typ PPAM Paladium, och en växelriktare av typ Sunny Tripower 8000 TL så skulle det produceras ungefär 7600 kWh/år. Det finns även möjlighet att få statligt solcellsstöd på upp till 45% av investeringskostnaden. Det innebär att bara 55% av priset behöver betalas med egna pengar. Dessutom så kan överskottet som solpanelerna producerar säljas.Den totala kostnaden för att energianpassa huset skulle uppskattningsvis hamna på ungefär 439100 kr utan solcellsstöd, samt 368100 kr med solcellsstöd. Då antas det att ingen mängdrabatt fås och att priserna inte är nedprutade. Det kan alltså potentiellt bliännu billigare än beräknat.Om solcellsstöd kan fås så är det fördelaktigt att ingå avtal om mikroproduktion med Vallentuna Energi, som tillämpar nettodebitering. Om huset är bebott året om så blir den uppskattade payback-tiden 6 år, och NPV-värdet blir 654966 kr. Om huset bara är bebott under åtta månader så blir motsvarande siffror 9,9 år respektive 231383 kr. Notera att dessa siffror gäller då det energianpassade huset jämförs med ett vanligt hus meddirektverkande el.Om solcellsstöd inte kan fås så är det bättre att ingå avtal om mikroproduktion med Telge Energi. De tillämpar inte nettodebitering, men de köper överskottselen för ett mycket fördelaktigt pris på 2,5 kr/kWh om solcellsstöd inte har erhållits. Om huset är bebott året om så blir den uppskattade payback-tiden 6,4 år och NPV-värdet blir 642716 kr. Om huset är bebott under åtta månader så blir siffrorna istället 10,2 år och 179914 kr.

  • 2.
    Engström, Maria
    et al.
    Linköping University, Department of Medical and Health Sciences, Radiology.
    Karlsson, Thomas
    Linköping University, Department of Behavioural Sciences and Learning, Disability Research.
    Landtblom, Anne-Marie
    Linköping University, Department of Clinical and Experimental Medicine, Neurology.
    Craig, A. D. (Bud)
    Atkinson Research Laboratory, Barrow Neurological Institute, Phoenix, AZ.
    Mental energy: graded co-activation of the anterior insular and anterior cingulate cortices during challenging working memory,  visual perception and motor speed tasks.Manuscript (preprint) (Other academic)
  • 3.
    Carlander, Jakob
    Linköping University, Department of Management and Engineering, Energy Systems.
    Att bygga bostäder enligt miljöbyggnadskrav: En fallstudie i området Nya Wahlbecks2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Energy and resource efficiency is an important part in moving towards a sustainable society. In the year 2013, the total energy use in Sweden was 563 TWh and approximately 26 % of the energy was used in the residential and service sector. Within the residential and service sector, nearly 60 % of the used energy is for heating (Energimyndigheten, 2015). The construction of energy efficient buildings is a central part in creating a sustainable society and Nya Wahlbecks is supposed to become a city district which will show that it is possible to increase growth, quality of life and well-being and at the same time decrease the use of non recyclable and non reusable resources.The primary purpose of this master thesis has been to generate suggestions on how to design the residential buildings in the new city district Nya Wahlbecks, which will be built in east Valla in Linköping, so they can be certified in accordance to the environmental certification system Miljöbyggnad. Besides the primary purpose an investigation on how much electricity that can be generated with photovoltaic and how much energy that can be saved by the use of solar heating panels, has also been conducted. Finally a comparison in emissions of CO2-eqvivalents between a building that just meets the criteria´s of Boverkets Byggregler (BBR) and the generated building models was done.The results which the case study has generated, clearly shows that it is possible to build the new residential buildings in Nya Wahlbecks so that they will meet the different criteria’s for grade Silver and Guld from Miljöbyggnad. The requirements from Miljöbyggnad aim to have as low energy use as possible at the same time as a good indoor climate is kept. These two factors can be contradictions to one another, as for instance low energy use can be reached by having thicker insulation, but thicker insulation often results in higher indoor temperature which can then lead to deterioration in indoor climate. The investigations of energy use and indoor climate were conducted through simulations in the building-simulation program IDA-ICE, where several optimizations were done for different parameters to finally meet the requirements from Miljöbyggnad. Simulations with solar panels for heating and generation of electricity were also conducted with IDA-ICE. The results of the study shows that nearly 60 % of the used electricity in the project building can be generated from photovoltaic panels placed on the roof of the building. About 9 % of the buildings heating energy can be produced with solar panels placed in the same way as the photovoltaic ones. When it comes to emissions of CO2-eqvivalents there would be a difference in approximately 19 tons, which is equivalent to about 30 %, if the building meets the requirements of Miljöbyggnad Silver instead of just meeting BBR´s requirements.

  • 4.
    Yang, Jian
    et al.
    Drexel University, PA 19104 USA; Drexel University, PA 19104 USA; Nanjing Technical University, Peoples R China.
    Naguib, Michael
    Oak Ridge National Lab, TN 37381 USA.
    Ghidiu, Michael
    Drexel University, PA 19104 USA;.
    Pan, Li-Mei
    Nanjing Technical University, Peoples R China.
    Gu, Jian
    Nanjing Technical University, Peoples R China.
    Nanda, Jagjit
    Oak Ridge National Lab, TN 37381 USA.
    Halim, Joseph
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. Drexel University, PA 19104 USA; Drexel University, PA 19104 USA.
    Gogotsi, Yury
    Drexel University, PA 19104 USA; Drexel University, PA 19104 USA.
    Barsoum, Michel W.
    Drexel University, PA 19104 USA; Drexel University, PA 19104 USA.
    Two-Dimensional Nb-Based M4C3 Solid Solutions (MXenes)2016In: Journal of The American Ceramic Society, ISSN 0002-7820, E-ISSN 1551-2916, Vol. 99, no 2, 660-666 p.Article in journal (Refereed)
    Abstract [en]

    Herein, two new two-dimensional Nb4C3-based solid solutions (MXenes), (Nb-0.8,Ti-0.2)(4)C3Tx and (Nb-0.8,Zr-0.2)(4)C3Tx (where T is a surface termination) were synthesizedas confirmed by X-ray diffractionfrom their corresponding MAX phase precursors (Nb-0.8,Ti-0.2)(4)AlC3 and (Nb-0.8,Zr-0.2)(4)AlC3. This is the first report on a Zr-containing MXene. Intercalation of Li ions into these two compositions, and Nb4C3Tx was studied to determine the potential of those materials for energy storage applications. Lithiation and delithiation peaks at 2.26 and 2.35 V, respectively, appeared in the case of Nb4C3Tx, but were not present in Nb2CTx. After 20 cycles at a rate of C/4, the specific capacities of (Nb-0.8,Ti-0.2)(4)C3Tx and (Nb-0.8,Zr-0.2)(4)C3Tx were 158 and 132 mAh/g, respectively, both slightly lower than the capacity of Nb4C3Tx.

  • 5.
    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.  

  • 6.
    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.

  • 7.
    Kuei, Chun-Fu
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics.
    Transmission electron microscopy study on the formation of SiNX interlayer during InAlN growth on Si (111) substrate2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Ternary indium aluminum nitride (InXAl1-XN) semiconductor is an attractive material with a wide-range bandgap energy varied from ultraviolet (Eg(AlN): 6.2 eV) to near infrared (Eg(InN): 0.7 eV). With tuning composition, it can be widely used to many optoelectronic device applications. In this thesis, I have studied InXAl1-XN film deposited on Si (111) substrate using natural and isotopically enriched nitrogen as reactive gas by reactive magnetron sputter epitaxy (MSE). Four series of experiments were performed, which are I. InAlN presputtering, II. InAlN sputter deposition, III. InAlN direct deposition, and IV. InAlN direct deposition using isotopically enriched nitrogen. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). The θ-2θ XRD scan confirms that the designed composition x = 0.17 of InXAl1-XN film was obtained. TEM images shows that an amorphous interlayer with a thickness ranging from 1.2 nm to 1.5 nm was formed between Si substrate and InXAl1-XN film. However, high-resolution TEM shows that the interlayer actually contains partial crystalline structures. EDX line profile indicates that the chemical composition of the amorphous interlayer is silicon nitride (SiNX). By comparing d-spacing measurement of partial crystalline structures with EDX line profile, it reveals that partial SiNX crystal is formed in the interlayer. Nonetheless, the samples (IAD01, IAD02, IAD03, IAD04), grown without presputtering procedure, contain both crystalline SiNX and InXAl1-XN embedded in the amorphous interlayer. It means that SiNX and InXAl1-XN film can be directly grown on the substrate in the beginning of deposition. Moreover, the samples (IAD01, IAD03), quenched directly after deposition, have less crystalline structures in the interlayer then the samples (IAD02, IAD04), maintained at 800℃ for 20 min.

  • 8.
    Hanson, Maryam
    Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems.
    Study on Smart Dust Networks2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis work is done for the department of Electronic System at The Institute of Technology at Linköping University (Linköpings Tekniska Högskolan). Study's focus is to design and implement a protocol for smart dust networks to improve the energy consumption algorithm for this kind of network.

    Smart dust networks are in category of distributed sensor networks and power consumption is one of the key concerns for this type of network. This work shows that by focusing on improving the algorithmic behavior of power consumption in every network element (so called as mote), we can save a considerable amount of power for the whole network.

    Suggested algorithm is examined using Erlang for one mote object and the whole idea has put into test for a small network using SystemC.

  • 9.
    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.

  • 10.
    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.

  • 11.
    Gustafsson, Daniel
    et al.
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics.
    Larsson, Isak
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics.
    Solvärme i Singapore2015Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

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

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

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

  • 12.
    Andreeva, Radostina
    et al.
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Glaa, Besma
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    Public Intermediaries as KeyFacilitators of Diffusion: The Case of Renewable Energy in Sweden2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Diusion of renewable energy technologies(RETs) is an important challengeof the current century. Much of the existing research has put a focus on understandingthe diusion of RETs through the perspective of systems of innovation. However, two recent studies highlight the importance of the actors in the process- those who adopt the RETs. With the current study we continue thisactor perspective by focusing on the adoption process as the driver of the massdiusion. We bring together the two streams of diusion of innovation and innovationintermediaries in a thesis that aims to show how comprehending thesingle adoption process and providing support to the adopters at every singlephase of it can facilitate diusion.

    Our focus is fully on public intermediaries. We show that public innovationintermediaries known in research for their support for the innovation systemhave an unexplored facet i.e. that of supporters at the adopter level. The thesiscontributes to previous literature showing that public intermediaries are thesupporters of adopters of RETs at the very beginning of the process which wascurrently unexplored. Moreover, we demonstrate that public intermediaries arepresent in the later phases of the adoption process as well being their impartialitya main advantage in comparison to private intermediaries. The study revealstwo key roles of public intermediaries in the pre-adoption phase of the processand four roles in the implementation phase.

    To complete the research we use qualitative methods and particularly groundedtheory methodology for data collection and analysis. Data is collected throughface-to-face long interviews with six public and/or non-prot intermediaries locatedin the Swedish county, Ostergotland. The study brings about the recognitionof public intermediaries as direct supporters of adopters of RETs in practice,oers ways of rethinking the existing policies in order to speed up diusion ofRETs and expands the arena for further research with focus on the interactionbetween intermediaries and adopters.

  • 13.
    Pettersson, Thomas
    Linköping University, Department of Mathematics, Computational Mathematics. Linköping University, Faculty of Science & Engineering.
    Analysis and implementation of the Smooth Discrete Element Method in AgX2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    We encounter granular materials on a daily basis. We walk up a gravel path or we eat our breakfast cereals. When handling granular materials on an industrial scale it is important to do so efficiently, to avoid unnecessary energy losses, wear and tear. To help designing efficient tools for handling these materials engineers uses numerical simulations.

    This project investigates the difference between the two main approaches to simulation of granular materials, the Smooth- and Non-smooth Discrete Element Methods by implementing the Smooth method into AgX dynamics were the Non-smooth method already is implemented, and then setup and execute a range of experiments to investigate their differences.

    The investigation shows both advantages and weaknesses for both methods. The result of simulations with smooth discrete element method are more consistent than with the nonsmooth discrete element method with respect to choice of time step and other parameters that can be chosen for the simulation. Smooth discrete element method have problems when it comes to extreme situations.

    The relative simulation time for system as large as treated by this project (more than1000) can not be shown to depend on the size of the system.

  • 14.
    Lindholm Pirttilä, Christopher
    et al.
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Nordh, Oscar
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Relativvärderingsbaserade investeringar. Hur väl fungerar de i olika branscher?: En studie över samtliga företag noterade i Norden mellan åren 2005–20142015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: This thesis has been executed in order to bring clarity into the matter whether relative valuation works as an investment strategy in the Nordic region between the years 2005 and 2014. Whether the strategy performs differently if the markets are sorted by sector affiliation, as well as if previously commonly used key ratios can generate different returns in different sectors is an unexplored area. Previous studies have focused on examining entire markets or specific industries where the results partially have been interpreted with behavioral finance.Aim: The aim of the thesis is to analyze whether there are any differences in how well relative valuation works as an investment method in different sectors, in order to generate excess return; as well as if it is statistically possible to find a connection between sectors and key ratios.Completion: A quantitative approach is used where the stocks are sorted into quartile portfolios in accordance with their sector affiliation and based on their valuation relative to sector competitors. The portfolios are then rebalanced on a yearly basis and returns are calculated on monthly and cumulative basis. Furthermore the portfolios are evaluated using risk measures, a diversification process and behavioural finance.Results: Relative valuation can be used to generate excess return in all sectors except in the energy sector. A discrepancy in returns is shown, depending on which sector, quartile and key ratio that is used for the investment. Moreover, diversification effectively lowers the risk without lowering the return at the same pace. Behavioural finance can only partially explain the differences in return between the portfolios.

  • 15.
    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. 

  • 16.
    Davidsson, Joel
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics.
    Orbital-free Density-Functional Theory in a Finite Element Basis2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this work, we have implemented an orbital-free density functional theory (OF-DFT) solver using the finite element method. In OF-DFT, the total ground state energy is minimized directly with respect to the electron density, rather than via orbitals like in the standard Kohn-Sham approach. For this to be possible, one needs an approximation of a universal density functional of the non-interacting kinetic energy. Presently available approximations allow for computation with very low computational expense, but which gives inaccurate energies. A stable OF-DFT code can be used as a testbed for new kinetic energy functionals and provide the necessary tool for investigating the accuracy of OF-DFT calculations for complex systems. We have implemented Thomas-Fermi theory with and without nuclear cusp condition, as well as additional exchange terms of Dirac and Amaldi. The program uses an extended version of the steepest descent in order to find the minimizing density in the variational principle. Our results include convergence tests for the hydrogen atom, weak bonding in the H2 molecule, and accurate results for the lightest noble gases (He, Ne, Ar). For heavier atoms (Kr, Xe, Rn), the results are less accurate. In addition, we consider hydrogen in the simple cubic structure without the cusp condition, which is a first attempt to use the code for periodic systems. Lastly, we discuss some possible improvements for the iterative process towards the minimizing density, as well as other possible directions for future development.

  • 17.
    Öqvist, Johanna
    et al.
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Bergfelt, Petra
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Nudge; en knuff i rätt riktning?: Ett beteendeekonomiskt experiment om svenskars attityder till nudge2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Behavioral interventions – so-called nudge – aim to get individuals to make decisions that are beneficial for the individual as well as for the society by making subtle changes in the decision context. Policymakers worldwide use nudge as an additional policy tool. However, nudging has been criticized for its questionable ethical principles and to date the debate concerning these issues has largely proceeded without much input from the general public. When should nudges be deemed as acceptable and when are they perceived as restrictive of an individual’s freedom of choice? Should all nudges be perceived as equal or do attitudes depend on specific characteristics of the nudge-intervention?The objective of this study is to elicit public views on the use of nudges with regard to i) acceptance and ii) restrictive on an individual’s freedom of choice. In particular, the study examines attitudes towards pro-self nudges (i.e. focusing on private welfare) and pro-social nudges (i.e. focusing on social welfare) as well as nudge of three degrees of intrusiveness (categorization of level of intrusiveness on the individual’s autonomy). In addition, we explore how individual differences in worldview affect attitudes towards nudge. A general population sample in Sweden (n=677) were presented with nudge-scenarios concerning three policy contexts; energy saving, smoking and retirement, in which they responded to questions regarding attitudes. To explore preferences towards pro-self and pro-social nudge, we used a contrastive vignette technique. To test for individual differences, measures on cultural cognition were included.The result show that all nudge-scenarios have majority support (for acceptance). However, a quarter of the nudge-scenarios were perceived as restrictive of an individual’s freedom of choice. Differences regarding attitudes towards pro-self and pro-social nudge cannot be ensured statistically. For degree of intrusiveness we found that a higher degree of intrusiveness reduces the level of acceptance for the nudge-scenarios. As for restrictive on an individual’s freedom of choice, we found the remarkable result that a medium degree of intrusiveness is perceived as less intrusive than a high degree of intrusiveness. Furthermore, we found that individuals with an individualistic worldview tend to be less accepting towards nudge-scenarios.In conclusion, our results indicate that there is no general accepted formula for how a nudge should be designed. Highlighting this is a fundamental aspect both for broadening the theory of nudge as a policy tool as well as to implement efficient nudges in the future.

  • 18.
    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.

  • 19.
    Lundmark, linda
    Linköping University, The Tema Institute, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Definitionen och tolkningen av miljöproblemen och möjliga lösningar: En studie kring Svenska miljöorganisationers argument och perspektiv2015Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    In this study, four different Swedish environmental organizations are examined and compared in order to highlight how they view theenvironmental problems and possible solutions. People from the environmental organizations Naturskyddsföreningen, Klimataktion, Fores andHela Sverige ska leva were interviewed. Additional information was gathered from the various environmental organizations' websites andcatalogs. To get an in-depth discussion and to relate the analyzed material to a larger theoretical context, the arguments of the environmentalorganizations have been analyzed in relation to different environmental discourses. Two relevant theoretical frameworks for this study is Hajersdiscursive theory, which relate to environmental problems and environmental conflicts, and Swyngedouws view of how today's symbolization of"Nature" affect and limit environmental policy. The result shows that the various environmental organizations have a different approach toenvironmental problems and possible solutions. Fores perspective can be related to the ecological modernization discourse, where theenvironmental problem is seen as something that could be dealt with within the current socio-economic frames with a continued economicgrowth. Naturskyddsföreningen do not criticize economic growth, but they believe that the economic systems should be driven in a moreenvironmentally conscious direction. Their perspective can be related to the ecological reconsideration discourse (den ekologiska omprövningensdiskurs). Both Klimataktions and Hela Sverige ska levas approach to environmental problems can be related to the system criticism discourse(Systemkritikens diskurs), where market-based solutions and technological developments are not considered to be enough to solve environmentalproblems. Instead we need to extensively change our way of life with reduced consumption and energy use.

  • 20.
    Linder, Tova
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Science & Engineering.
    Persson, Pontus
    Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Science & Engineering.
    Analyzing the predictability of download speeds in mobile networks2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In a highly mobile and networked society the need to download large amounts of data on a mobile network is inevitable. This thesis analyzes the predictability of download speeds in mobile networks to be able to schedule downloads while in areas with high download speeds. This decreases the download time and thus the energy wasted downloading. The data analyzed is from Bredbandskollen. We find that in areas of 200 x 200 meters the download speed is easiest to predict due to a low covariance. We also find that areas with high average download speed are more likely to have neighboring areas with similar download speed than areas with low average download speed, making it easier to predict the download speed when moving between such locations. Finally, we show paths in urban areas where a user can move long distances and experience similar download speeds.

  • 21.
    Grozelier, Anna
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Labrador and German shepherd breed differences in dog-human communication2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As our long-term companions, dogs’ communication with us is perhaps the most developed of all human- animal ones. This study was aimed to investigate breed differences of German Shepherds and Labradors in dog-human communication. This was obtained through two tests: a problem-solving task and a pointing test. These two tests target both directions of communication: how much dogs understand and respond to the pointing and how they communicate with humans when facing a problem. Additionally, hair cortisol was measured in the dogs and dog owners filled a behavioural questionnaire (C-BARQ). The main breed difference I found was that Labradors performed better in both tests. I also found that the latency of the dogs’ choices in the pointing test correlated with many factors, e.g. they chose quicker when: choosing correctly, when they had many physical contacts with the experimenter in the problem-solving task, when they were more intense, energetic dogs, when they had higher hair cortisol levels and when they had a confident body posture. This indicates that the latency of choice could depend on the confidence of the dog and on the trust in the experimenter as well as on energy level and focus ability. Overall, this study revealed a limited amount of breed differences, compared to a parallel study on Labrador types (hunting and show dogs), showing that intra-breed differences can be more important than inter-breed ones on a behavioural level. 

  • 22.
    Örtenberg, Alexander
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Parallelization of DIRA and CTmod Using OpenMP and OpenCL2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Parallelization is the answer to the ever-growing demands of computing power by taking advantage of multi-core processor technology and modern many-core graphics compute units. Multi-core CPUs and many-core GPUs have the potential to substantially reduce the execution time of a program but it is often a challenging task to ensure that all available hardware is utilized. OpenMP and OpenCL are two parallel programming frameworks that have been developed to allow programmers to focus on high-level parallelism rather than dealing with low-level thread creation and management. This thesis applies these frameworks to the area of computed tomography by parallelizing the image reconstruction algorithm DIRA and the photon transport simulation toolkit CTmod. DIRA is a model-based iterative reconstruction algorithm in dual-energy computed tomography, which has the potential to improve the accuracy of dose planning in radiation therapy. CTmod is a toolkit for simulating primary and scatter projections in computed tomography to optimize scanner design and image reconstruction algorithms. The results presented in this thesis show that parallelization combined with computational optimization substantially decreased execution times of these codes. For DIRA the execution time was reduced from two minutes to just eight seconds when using four iterations and a 16-core CPU so a speedup of 15 was achieved. CTmod produced similar results with a speedup of 14 when using a 16-core CPU. The results also showed that for these particular problems GPU computing was not the best solution.

  • 23.
    Molin, Johan
    Linköping University, The Tema Institute, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    The Present and Future Role of Energy Recovery in Waste Management - A Case Study of Linköping and Norrköping2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the European Union 500 million tonnes of waste are either incinerated without energy recovery,or deposited in landfills, which could have been recycled instead. The European Union initiated theCircular Economy Package in order to decrease the amount of waste being generated, lost inlandfills, and to increase the recycling and usage of recycled material. However, the CircularEconomy Package did not contain any targets focusing on energy recovery, and only mentionedenergy recovery as having a role in decreasing the amount of waste deposited in landfills. TheCircular Economy Package was in the end of 2014 withdrawn but will come back with moreambitious targets. In Sweden energy recovery is treating more than 50% of the municipal waste andwould then be affected by the targets of the Circular Economy Package when it comes back.This thesis focuses on Linköping and Norrköping to identify the what role energy recovery have inthese municipalities, both present and future, as well as asking the questions of how waste is valuedas a resource.The results were that both municipalities thought that it was important to have separate sorting ofmunicipal waste, to separate organic waste from the rest, in order to use it in material recycling andthe rest in energy recovery. In both municipalities the energy recovery had the role of treating themunicipal waste which was found to be not recyclable, as well as to deliver heat and electricity. Allof the organisations were identified to have a high environmental value on waste, but the economicvalue of waste were low or negative. The municipalities also knew little of the Circular EconomyPackage, but were aware of it, while the energy companies knew a little more of it, but still littlecompared to their national interest organisations Avfall Sverige and Svensk Fjärrvärme. All of theorganisations had identified similar challenges such as increased focus on recycling, minimisationof waste, but also a focus on decreasing amount of hazardous substances in products in order todecrease the amount of waste which needed to be deposited in landfills.

  • 24.
    Zeeshan, Jafer
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    U.S. Governmental incentives and policies for investment in electric vehicles and infrastructure2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of study is to research the development of electric vehicle technology in the United States. This study describes the United States public policies towards electric vehicle technology and system of innovation approaches. The government roles with the help of national system of innovation have been also covered in this study.

    The point of departure was the study of available literature and U.S energy policy acts which illustrates that the break-through in electric vehicles still not only depended on better battery technology and infrastructure for charging stations but also on social, economic and political factors. The important actors involved in the process are both at local and international level are private firms, governmental departments, research and development (R&D) institutes, nongovernment organizations (NGO’s) and environmental organizations etc. The arguments which are put forward in the background of development of such technologies are to reduce dependence on foreign oil and to reduce emissions of harmful gasses.

  • 25.
    Ahmed, Uday
    et al.
    Linköping University, Department of Management and Engineering, Manufacturing Engineering. Linköping University, Faculty of Science & Engineering.
    Ayo, Priscilla
    Linköping University, Department of Management and Engineering, Manufacturing Engineering. Linköping University, Faculty of Arts and Sciences.
    Developing Common Questions about Integrated Product Service Engineering (IPSE), Ecodesign and Engineering Education2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the recent years, more and more manufacturing firms recognize the benefit of providing products together with related services with an aim to gain higher profits as compared to supplying products without additional services. On the other hand, the competition in the global markets has been increased dramatically through increased sales of services in order to gain additional value for their products. In addition, several environmental challenges such as climate change, pollution, global warming impact, greenhouse gases emissions have played a vital role by influencing on the production protocols and trend of the companies. These challenges forced manufacturing countries to take into consideration environmentally conscious approach to their design thinking and industrial production processes. As a result, it became an important drive for manufacturing industries to shift from traditional product-oriented to service-oriented business models that has been witnessed during the last few years.

     

    The objective of this study research is to develop common questions that capture fundamental and common issues about Integrated Product Service Engineering (IPSE), Design for Environment (DFE) and Engineering education are effectives for industries to check and develop their knowledge, because the Engineering education plays a necessary role in associating socio-ethical knowledge with scientific and technological advances. The strategy taken to conduct this thesis task was first to study and understand the concept of Product Service System (PSS), IPSE, and Ecodesign as well as Engineering Education. Informative knowledge on these concepts were collected by reviewing several related journal articles, CIRP IPS2 conference proceedings.

     

    In this thesis the concepts of PSS, IPSE, DFE and Engineering Education discussed to develop the key common questions and issues to address the environmental, economic and social problems. Since PSS aims to reduce consumption through alternative schemes of product use as well as to increase overall resource productivity and dematerialization, but IPSE does not focus on a single factor but incorporates a wide range of factors such as environmental, social and economic issues. Whilst one of the main problems in this research focused on how to develop and strengthen the relationship between the academia and industry, and how this relation can be used to improve the academic performance and scientific research at universities and transfer them to industry.

     

    Sustainability and the life cycle concept have become a main solution for various problems such as a growing world population and a change in the industrial culture to come. As results Ecodesign and environmental considerations, financial aspects, product improvement as well as the commercial aspects were discussed in this project by understanding the previous concepts. The university considered as an important base of cultivating the talents, basic of inputs business organizations which help them to develop and improve their level of performance and quality of their products and services, and enhance its competitive position in the market. Changes in organized science further encouraged university interests in expanding technology transfer, because the scientific disciplines play an important role in influencing the type of interactions with industry as well as the University and Industry collaboration became the basic method of solving the problems to achieve (environmental, economic and social) sustainability.

  • 26.
    Szilassy, Martin
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Örn, Daniel
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Low Energy GPS Positioning: A device-server approach2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    GPS is widely used for localization and tracking, however traditional GPS receivers consume too much energy for many applications. This thesis implements and evaluates the performance of a low energy GPS solution, including a working hardware prototype, that reduces energy consumption significantly. The prototype operates for 2 years on a coin cell battery, sampling every minute. The corresponding time for a traditional receiver is 2 days. The main difference is that a traditional receiver requires 30 seconds of data to estimate a position; this solution only requires 2 milliseconds of data, a reduction of a factor 15 000. The solution consists of a portable device, sampling the GPS signal, and server software that utilizes Doppler navigation and Coarse Time Navigation to estimate positions. The median positioning error is at most 38 meters in our tests. We expect that this solution will enable positioning for billions of devices in the near future.

  • 27.
    Klarbring, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics. Linköping University, Faculty of Science & Engineering.
    A first-principles non-equilibrium molecular dynamicsstudy of oxygen diffusion in Sm-doped ceria2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Solid oxide fuel cells are considered as one of the main alternatives for future sources of clean energy. To further improve their performance, theoretical methods able to describe the diffusion process in candidate electrolyte materials at finite temperatures are needed. The method of choice for simulating systems at finite temperature is molecular dynamics. However, if the forces are calculated directly from the Schrödinger equation (first-principles molecular dynamics) the computational expense is too high to allow long enough simulations to properly capture the diffusion process in most materials.

    This thesis introduces a method to deal with this problem using an external force field to speed up the diffusion process in the simulation. The method is applied to study the diffusion of oxygen ions in Sm-doped ceria, which has showed promise in its use as an electrolyte. Good agreement with experimental data is demonstrated, indicating high potential for future applications of the method.

  • 28.
    Imani, Roghayeh
    et al.
    Univ Ljubljana, Fac Elect Engn, SI-1000 Ljubljana, Slovenia; [ 2 ] Univ Ljubljana, Fac Hlth Sci, SI-1000 Ljubljana, Slovenia .
    Pazoki, M
    Uppsala Univ, Angstrom Lab, Dept Chem, S-75120 Uppsala, Sweden.
    Boschloo, G ()
    Uppsala Univ, Angstrom Lab, Dept Chem, S-75120 Uppsala, Sweden.
    Turner, Anthony (Contributor)
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Kralj-Iglič, V (Contributor)
    Univ Ljubljana, Fac Hlth Sci, SI-1000 Ljubljana, Slovenia.
    Iglič, Ales
    Univ Ljubljana, Fac Elect Engn, SI-1000 Ljubljana, Slovenia.
    Band edge engineering of TiO2@DNA nanohybrids and implications for capacitive energy storage devices.2015In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 7, no 23, 10438-10448 p.Article in journal (Refereed)
    Abstract [en]

     Novel mesoporous TiO2@DNA nanohybrid electrodes, combining covalently encoded DNA with mesoporous TiO2 microbeads using dopamine as linker, were prepared and characterised for application in supercapacitors. Detailed information about donor density, charge transfer resistance and chemical capacitance, which have important role in the performance of an electrochemical device, were studied by electrochemical methods. The results indicated the improvement of electrochemical performance of TiO2 nanohybrid electrode by DNA surface functionalisation. A supercapacitor was constructed from TiO2@DNA nanohybrids with PBS as electrolyte. From the supercapacitor experiment, it was found that the addition of DNA played an important role in improving the specific capacitance (Cs) of the TiO2 supercapacitor. The highest Cs value of 8 F/g was observed for TiO2@DNA nanohybrids. The nanohybrid electrodes were shown to be stable over long-term cycling, retaining 95% of their initial specific capacitance after 1500 cycles.

  • 29.
    Andreasson, Pierre
    et al.
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Siverskog, Jonathan
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Cross-market linkages and the role of speculation in agricultural futures markets2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this study we analyse the role of speculation in forging cross-market linkages between agriculture, equity and crude oil over the period 1992-2014. The market interdependence of ten U.S. traded agricultural commodities futures is measured through the spillover index of Diebold and Yilmaz (2009, 2012) and the dynamic conditional correlation framework of Engle (2002). Utilising data from the U.S. Commodity Futures Trading Commission, ve dierent measures of speculation are constructed, which are used to examine the long-run and short-run dynamics between market integration and speculation. To explore time-varying characteristics in this relationship, and as a test for robustness, we perform a sub-sampling analysis for the periods 1992-2006 and 2006-2014.

    We show that cross-market linkages grew stronger post-2005, particularly in the aftermath of the 2008 global financial crisis. The results of our econometric analysis indicate that any conclusions regarding the role of speculation in this process are highly sensitive both to the choice of market integration measure, as well as to how the extent of speculation is captured. Overall, though, there is little to indicate that speculation has played an important role in creating cross-market linkages. We do provide some evidence of market integration increasing with market size, but other factors, such as inflation and exchange rates, seem to provide better explanations of agriculture-equity-energy price dynamics. In line with previous research, we also find market interdependence to increase with stock market uncertainty, which suggests that the diversification benefits of commodity futures investments are actually reduced when needed the most. Considered together with our findings on the sizes of markets, which are increasingly made up of speculators, it appears at least possible that financialisation has made food markets more vulnerable to disturbances in financial markets.

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

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

  • 31.
    Shtepliuk, I.
    et al.
    NASU, Ukraine.
    Podolskaia, N.
    RAS, Russia; RAS, Russia; St Petersburg Academic University, Russia.
    Lashkarev, G.
    NASU, Ukraine.
    Phase Field Modeling of the Zn1-xCdxO Solid Solutions2014In: Acta Physica Polonica. A, ISSN 0587-4246, E-ISSN 1898-794X, Vol. 126, no 5, 1079-1082 p.Article in journal (Refereed)
    Abstract [en]

    The analysis of spinodal decomposition in the Zn1-xCdxO ternary alloy was carried out by means of the nonlinear Cahn-Hilliard equation. Interaction parameter as a function of composition x was provided by valence force field simulations and was used in this analysis. The morphological patterns for the ternary alloys with different Cd content (x = 5, 10, 50%) were experimentally obtained using the semi-implicit Fourier-spectral method. The simulated microstructure evolution Zn0.95Cd0.05O demonstrates that the microstructure having a form of bicontinuous worm-like network is evolved with the progress of aging. An effect of the phase-field mobility and the gradient energy on the microstructure evolution of the Zn1-xCdxO alloys is discussed. It was found that the higher driving force for the decomposition in the higher Cd content film results in a higher decomposition rate revealed by the simulations. The temporal evolution of the simulated Zn0.95Cd0.05O microstructure is in good agreement with experimental results, which have been obtained for this solid solution.

  • 32.
    Danielsson, William
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Waldmann, Sebastian
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Avoiding Unnecessary 3G Data Transmission Through Mobile Sensors2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In recent years, instant messaging (IM) has started to replace short message service (SMS) in communication. IM offers more functionality but there is a great downside. IM demands more power and drains the mobile device battery faster. This paper shows the energy consumption of  IM when the user is not using the application and how the consumption  can be reduced by enabling mobile sensors and sending fewer packets by the application. We began by investigating the various sensors that are supported by mobile devices. With the retrieved vendor information, we evaluated the different sensors and chose two sensors, light sensor and proximity sensor in order to study their use for reduction of energy in  an instant messaging scenario. These two sensors can together estimate if the mobile device is placed in the pocket of the user. The development of a simple IM application was completed and sensors were used to create an extension to the application. The extension would lengthen the interval between the updates of the automatic update function when the mobile was inactive, reducing the energy consumption.

    Two types of tests were performed. The first test evaluated if the extension would correctly deduce that the mobile device was placed inside a pocket. The mobile device with the pocket-aware application was used in different common situations and the tests showed that the extension made a correct computation in seven of nine situations. The faulty situations were when the mobile device is placed with the screen faced down to a surface. The second test compared the energy consumed by a pocket-aware application compared to a mobile device without our extension. Based on the results that we retrieved, we estimated that during a one minute period the pocket-aware application with an update interval of ten seconds could save on average 12% and could save on average 62% when the update interval was increased to fifteen seconds.

  • 33.
    Polis, Rihards
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology. Riga Technical University.
    EnergyBox: Tool improvement and GUI2014Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    EnergyBox is a parametrised estimation tool that uses packet traces as input to simulate the energy consumption of communication in mobile devices. This tool models the transmission behaviour of a smart phone by analysing a recorded packet trace from the device. The purpose of the thesis is to reimplement the original EnergyBox energy consumption modelling tool. The project aims to develop support for a graphical user interface (GUI) and a code base that is easier to modify and maintain.

    The motivation for the reimplementation of the tool is to simplify its usage and to structure the code so that new features can be added. The existing features such as the calculation of total power consumed by the packet trace and the modelling of a device's energy states are reimplemented and new features are developed. Among the new features, a GUI is added to simplify the usage of the application features such as the detection of the recording device's IP address and the ability to alter the configuration parameters used as input to the energy model.

    The application is written with a GUI and modularity in mind. This is achieved using Java's proprietary new GUI framework - JavaFX, which supports built-in chart and graph GUI elements, that can be easily integrated and supported. The energy modelling engines follow the semantics of the original implementation and the evaluation shows that the new implementation's results are identical to the original tool in 94.94% of the tested cases.

  • 34.
    Bransell, Sara
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences.
    Pappors reflektioner om hur, över tid pågående, konflikter med mamman drabbar barnet.2014Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the present study was to investigate the ability of fathers, who have participated in a combined therapy/self-help group, of young children to appreciate the effects of prolonged conflicts in the family on the children, e.g. their ability as fathers to assume the children's perspective on the matter.

    Ten fathers no longer living with the mothers, with whom they still had unresolved issues, participated in individual interviews concerning different questions that might be of importance to children exposed to family conflict. The interviews were based on two fictitious cases describing the situation of children whose parents are in dispute over custody. All of the participating fathers emphasized how difficult it was to keep the welfare of the child in focus, while having an ongoing conflict with the mother. They also expressed problems in judging what practical daily life measures would be best for the child during the conflict. Moreover, they raised the issue of not being able to focus on parenting, putting all their energy into managing their ex-partner instead. Hence, focusing on managing a conflict occurred at the expense of the relationship to their children. The participants also expressed how the fathers in the fictitious cases, and in their own situation, should be concerned with not intensifying an already difficult situation for the children as long as they don’t understand the children's perspectives.

    It can be concluded that the participants obtained an increased awareness of the importance of being more sensitive to the needs of their own children due to the support from the group treatment. They could see parenting as a lifelong task with responsibilities on them even when the relationship with mother had ended.

  • 35.
    Strömbom, Johanna
    et al.
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Carlsson, Malin
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Vad underlättar respektive hindrar fysisk aktivitet hos personer med långvariga smärtor?: En kvalitativ intervjustudie2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Title: FacilitatorsandBarriers toPhysical ActivityamongPeople with Long-term Pain-A Qualitative Study.

    Authors: Malin Carlsson & Johanna Strömbom, Physiotherapy Programme, Faculty of Health Sciences, Linköping University, Sweden.

    Tutor: Britt Larsson, Docent of Occupational Medicine, Lector of Clinical Pain Research, Faculty of Health Sciences, Linköping University, Sweden.

    ABSTRACT

    Introduction: Exercise has been shown to have positive effects on long-term pain. There is, however, reported poor adherence in people with long-term pain. Previous research has demonstrated a number of facilitating and inhibiting factors to exercise for people with long-term pain but lay emphasis on the importance of further research with a broader approach to physical activity.Purpose: The aim of this study was to identify facilitating factors and barriers to physical activity as a treatment for long-term pain.Method: A qualitative study using semi-structured interviews was conducted with ten participants recruited through the Pain -and Rehabilitation Center in Linköping. Collected data was analysed based on a qualitative content analysis.Results: Facilitating factors were reported to be individually tailored, varied and enjoyable training, also support, fellowship, pain relief, motivation, progress, the desire to improve health, availability and knowledge. Pain, timing, lack of energy, difficulty initiating exercise, not having a need to exercise, lack of availability and knowledge, and furthermore embarrassment, laziness, fear, and lack of motivation were reported as being inhibitive.Conclusion: Factors that appeared in the results confirm previous research, this study presented additional factors such as difficulties initiating exercise and not having a need to exercise. Future research should apply presented factors in the design of treatment for patients with pain.Keywords: adherence, pain, physical activity, qualitative research.

  • 36.
    Kardell, Martin
    Linköping University, Department of Biomedical Engineering. Linköping University, The Institute of Technology.
    Automatic Segmentation of Tissues in CT Images of the Pelvic Region2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In brachytherapy, radiation therapy is performed by placing the radiation source into or very close to the tumour. When calculating the absorbed dose, water is often used as the radiation transport and dose scoring medium for soft tissues and this leads to inaccuracies. The iterative reconstruction algorithm DIRA is under development at the Center for Medical Imaging Science and Visualization, Linköping University. DIRA uses dual-energy CT to decompose tissues into different doublets and triplets of base components for a better absorbed dose estimation. To accurately determine mass fractions of these base components for different tissues, the tissues needs to be identified in the image. The aims of this master thesis are: (i) Find an automated segmentation algorithm in CT that best segments the male pelvis. (ii) Implement a segmentation algorithm that can be used in DIRA. (iii) Implement a fully automatic segmentation algorithm.

    Seven segmentation methods were tested in Matlab using images obtained from Linköping University Hospital. The methods were: active contours, atlas based registration, graph cuts, level set, region growing, thresholding and watershed. Four segmentation algorithms were selected for further analysis: phase based atlas registration, region growing, thresholding and active contours without edges. The four algorithms were combined and supplemented with other image analysis methods to form a fully automated segmentation algorithm that was implemented in DIRA.

    The newly developed algorithm (named MK2014) was sufficiently stable for pelvic image segmentation with a mean computational time of 45.3 s and a mean Dice similarity coefficient of 0.925 per 512×512 image. The performance of MK2014 tested on a simplified anthropomorphic phantom in DIRA gave promising result. Additional tests with more realistic phantoms are needed to confirm the general applicability of MK2014 in DIRA.

  • 37.
    Lindgren, Lina
    Linköping University, The Tema Institute. Linköping University, Faculty of Arts and Sciences.
    Including Additional Land Use, Land Use Change and Forestry-activities under the Clean Development Mechanism: Discussions in the United Nations Climate Negotiations2011Report (Other academic)
    Abstract [en]

     

    Land use, land use change and forestry activities (LULUCF) can help mitigate climate change by creating a terrestrial carbon sink, removing carbon dioxide from the atmosphere, while at the same time help increasing adaptive capacity and reduce poverty. Still, carbon stored in biomass or soils are only stored temporary since natural or human induced disturbances can cause a total or partial loss of stored carbon.

    LULUCF-activities under the clean development mechanism (CDM),  one of the flexible mechanisms under the Kyoto protocol, have been limited to afforestation and reforestation (A/R) projects under the first commitment period. Joint implementation projects and national accounting  of  greenhouse  gas  reduction  can  in  addition  to  A/R-project  also  include deforestation,  revegetation,  forest  management,  cropland  management  and  grazing  land management. The exclusion of these types of activities from CDM has been questioned and debated recently.

    This briefing tracks the United Nations (UN) climate negotiations in regards to the possibility of including additional LULUCF-activities under CDM, mainly the negotiations occurring after the adoption of the Bali Road map.

    LULUCF under CDM has been discussed mainly in the Ad Hoc Working Group on Further Commitments for Annex I Parties under the Kyoto Protocol (AWG-KP). There are diverging ideas on whether a more holistic approach should be applied to the treatment of LULUCF under CDM or whether current structure should be kept. Costa Rica, Colombia, Mexico, Panama, El Salvador, New Zealand, Norway, Canada, Australia and several of the Least Developed Countries have been positive towards including additional LULUCF-activities. Some of the arguments brought up are that the LULUCF-sector holds a large potential to mitigate climate change that is lost with the current structure and that a broader inclusion of LULUCF-activities would lead to an inclusion of all parts of the world in the benefits from CDM. China, Brazil and  Alliance of Small  Island States  have, on the other hand, been sceptical towards including additional activities arguing that there are too large uncertainties and that it creates an offset allowing developed nations to delay emission reduction in other sectors. The EU supports the current structure and rules but is open to discuss alternatives.

    The  AWG-KP  has  been  negotiating  a  new  LULUCF-decision,  which  has  not  yet  been adopted. In the draft LULUCF-decision from the Conference of Parties in Copenhagen 2009, the possibility of expanding LULUCF under CDM was however opened. In the draft decision the Subsidiary Body for Scientific and Technological Advice (SBSTA) is requested to initiate a work programme on additional LULUCF-activities. Since the LULUCF-decision is not yet adopted, SBSTA cannot initiate this work programme and whether they will be able to do so is dependent upon the outcome of the negotiations on the LULUCF-decision. LULUCF- activities under CDM have so far received little negotiation time.

    LULUCF and CDM have also been discussed outside the formal UN climate negotiations. Several  side events,  for  example,  have treated these questions,  both  for and  against  the inclusion of additional activities.

  • 38.
    Bodin, Gustav
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Jaber, Momamed
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Energiberäkning för påbyggnader2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Saving energy is important both economically and environmentally.

    The way we in Sweden build our houses and the rules that govern our energy usage has varied over the years.

    Åtvidabergstakvåningar is a company that perform superstructures in the shape of new penthouses for villas. Åtvidabergstakvåningar came with the initiative for the study, too get a picture of how the energy usage transformed for villas equipped with their penthouses. They also came with the initiative for the method to create time distinct villas and equip these with their penthouses.

    The study gives a picture of how the building envelop is composed and how the energy loss is through it. The study will also compare how the rules that govern energy loss and usage have transformed over the years.

    The result of the Study is an energy calculation that declares the energy usage for the time distinct villas with and without penthouses.

    The Result of the study shows that the older houses get a better energy performance after adding on the penthouses, while the new house got a value that was similar.

  • 39.
    Wiréhn, Lotten
    Linköping University, The Tema Institute, Tema Environmental Change. Linköping University, The Tema Institute, Centre for Climate Science and Policy Research . Linköping University, Faculty of Arts and Sciences.
    Climate Suitable Energy Crops and Biomass Energy Potentials: Assessment of the Current and Future Prospects in Estonia2010Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Development of biomass energy plantations is one approach to mitigate and adapt to climate change and the energy challenges related to it; however, climate change will affect the climate conditions and in turn the selection of crops and trees suitable for renewable energy sources. In Estonia, electricity is mainly based on oil shale but since their integration in the European Union they are required to increase the share of energy from renewable sources. In this study, the possible changes of suitable species are assessed by examining the current and the future prospects and potentials with biomass energy derived from energy plantations in Estonia, taking climate change into consideration. The biomass energy potentials for the species that are climate suitable in current and future time are manually estimated, using a case study approach when determining the yields. The study result suggests that biomass energy from crops and trees have great development possibilities and that climate is not a key limitation for the selection of suitable species; in addition, the energy crops and trees appear to suit the future climate conditions better than the current. The results indicate that the established national target of 25% of energy from renewable sources in gross final consumption of energy by 2020 could be achieved to a large extent by putting energy plantations into practice.

  • 40.
    Almquist, Mathias
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    Almquist, Viktor
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    A study on Android games: 3G energy consumption, CPU-utilization and system calls2015Independent thesis Basic level (university diploma), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The popularity of mobile games has increased drastically during the recent years andmany people use them as their main source of entertainment. Mobile gamescommunicate with other devices over the network which consumes a lot of energy,especially when connected to cellular networks (e.g., 3G). This high energy expensecan feel unjustified to the player since always-on network connectivity is not requiredin order to play most games.Furthermore, the number of malware-infected applications in offical applicationstores has increased significantly in the recent years. These malware-infectedapplications can gain unrestricted access and control of users phones which can be athreat to security. Information about the behaviour characteristics of games can beused to develop or improve systems for detecting malware applications.In this thesis, 20 popular Android games are analysed with a focus on the datacommunication, CPU utilization and system call behaviour. The main subject of thedata communication study is the 3G communication energy consumed by games. Thesystem call study aims at quantifying the number and type of calls used by games.This may be useful in a further study of harmful behaviour by apps.The profiling results presented in this report show that the communication energyvaries drastically among games. Games with a very similar gameplay can consumevery different amounts of energy which indicates that there is room for improvementsin many of the games. Ad-free games consume significantly less energy than gamesthat use in-app advertisements. The results show that improving the advertisementfetching policy could reduce the energy consumption of these games. The majority ofthe games can be played without network connectivity and therefore thecommunication energy consumed could be completely avoided. The thesis alsoshows that games use a wide variety of system calls and that many of the system callsare common among the games.

  • 41.
    Janzén, Johan
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Evaluation of Energy-Optimizing Scheduling Algorithms for Streaming Computations on Massively Parallel Multicore Architectures2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis describes an environment to evaluate and compare static schedulers for real pipelined streaming applications on massively parallel architectures, such as Intel Single chip Cloud Computer (SCC), Adapteva Epiphany, and Tilera TILE-Gx series. The framework allows performance comparison of schedulers in their execution time, or the energy usage of static schedules with energy models and measurements on real platform.

    This thesis focuses on the implementation of a framework evaluating the energy consumption of such streaming applications on the SCC. The framework can run streaming applications, built as task collections, with static schedules including dynamic frequency scaling. Streams are handled by the framework with FIFO buffers, connected between tasks.

    We evaluate the framework by considering a pipelined mergesort implementation with different static schedules. The runtime is compared with the runtime of a previously published task based optimized mergesort implementation. The results show how much overhead the framework adds on to the streaming application. As a demonstration of the energy measuring capabilities, we schedule and analyze a Fast Fourier Transform application, and discuss the results.

    Future work may include quantitative comparative studies of a range of different static schedulers. This has, to our knowledge, not been done previously.

  • 42. Ullah, Sami
    Carbon Capture and Storage: Major uncertainties prevailing in theFutureGen project2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Carbon Capture and Storage (CCS) is an old technology matrix with new concept to mitigate climate change while utilizing fossil fuels by advancing the technology. The various level of advancement in technology has been successfully demonstrated in some part of the world. However the technology has inherent uncertainty of not having commercial CCS plant. Efforts to make CCS commercially viable unfold uncertainties in numerous aspects of CCS technology. Beside the uncertainties in technology many barriers restrain CCS to become a successful climate mitigation technology. However the growing energy demand and urgent need to mitigate climate change through emission reduction favours CSS as transition to clean energy production. FutureGen 2.0 is the only large commercial scale CCS project, initiated in 2003 to test the commercial viability of the technology and to meet the U.S energy demands besides emission reductions target. The project resurrection in 2010 as FutureGen 2.0 after FutureGen termination in 2008 provides an opportunity to understand and analyse numerous uncertainties. However through document analysis only major three uncertainties i.e. policy and regulatory, economic and financial and public acceptance uncertainties are identified and analysed. The interlinkages between these uncertainties are also analysed. The study results show that above uncertainties constrained the project engendering new uncertainties i.e. timeframe uncertainties. This study also provides an insight about the sustainability implication of CCS by evaluating economic, environmental and social impact of CCS technology. It is still early to term the CCS as Sustainable technological innovation however for many years CCS would upset and restrain investment in other clean energy technologies like Renewable technology system. This study gives an input in sustainability of CCS and technological assessment study. This study is helpful in managing uncertainties and planning new CCS projects. 

  • 43.
    Haglund, Emelie
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, The Institute of Technology.
    Systematisk bedömning av våtmarksväxter som substrat för biogasproduktion2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

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

  • 44.
    Nyström, Sofie
    Linköping University, Department of Computer and Information Science, Human-Centered systems. Linköping University, Faculty of Arts and Sciences.
    Förståelse för visualiserad elförbrukning i publik miljö: En användbarhetsstudie av touchdisplayen Urban Energy2014Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [sv]

    Hur publika displayer skall utformas och anpassas efter sin miljö på bästa sätt är ännu ett outforskat område. I takt med att miljöfrågor blivit än mer aktuella i dagens samhälle har det också etablerats ett behov av att förändra vårt beteende exempelvis i form av energieffektivisering. Syftet med denna uppsats är att undersöka hur en publik touchdisplay för elvisualisering skall utformas för att vara förståelig, intuitiv och säker från publik genans. En användarstudie i form av en utvärdering av en interaktiv touchdisplay kallad Urban Energy monterad i Göteborg har gjorts under ledning av Interactive Institute Swedish ICT. Touchdisplayens primära syfte är att uppmärksamma förbipasserande på stadens elförbrukning och uppmuntra till energimedvetenhet.

    I denna studie rekryterades 17 förbipasserande deltagare villiga att testa denna display med hjälp av två uppgifter och en enkät. Resultatet i form av skattningsvärden och observationsprotokoll genererade en tabell med problem och designlösningar. Utifrån användbarhetsstudien kunde slutsatser dras exempelvis angående visuellt interaktionsområde, feedback vid aktiva val, förståelse vid zoomning i tid, termhantering samt kontextens betydelse för publika touchdisplayer. Avslutningsvis ges en diskussion utifrån användbarhetsstudien kring väsentliga aspekter vid utformning av denna typ av display rörande energivisualisering, touchbaserade gränssnitt och social exponering framför publika installationer. 

  • 45.
    Birgersson, Örjan
    Linköping University, Department of Management and Engineering, Machine Design. Linköping University, The Institute of Technology.
    Energiabsorberande Skyddstak2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Materialhantering är en växande bransch som medför att både antalet anställda och arbets-tempot ständigt ökas. En konsekvens av detta är att antalet olyckor med fallande objekt har ökat i samband med användning av truckar.

    I detta examensarbete har därför en undersökning av skyddstaket till truckserien staplare (Stacker, Pedestrian with platform, Electrically powered) genomförts. Syftet är att undersöka möjligheterna att ta fram en ny konstruktion på skyddstaket som, jämfört med den befintliga konstruktionen, kan absorbera energin från en fallande last på ett bättre sätt samt minskar den kvarstående deformationen. Detta för att kunna öka säkerheten för föraren ytterligare men även för att kunna öka produktiviteten av trucken genom att minimera servicetiden av taket efter större lastfall.

    Målet med arbetet är att ta fram en CAD-modell på en ny konstruktion av skyddstaket som ska kunna utgöra underlag för framtagning av en testprototyp. Projektet har följt en systematisk produktutvecklingsprocess i vilken det första steget är att ta fram en kravspecifikation på konstruktionen. Nästa steg är att arbeta fram idéer på olika lösningar som sedan utnyttjas i framtagningen av ett antal koncept. Därefter utvärderas koncepten och ett val genomförs om vilket koncept som ska vidareutvecklas.

    Resultaten visar att genom att använda en konstruktion innehållande stötdämpare kan stötkraften från den fallande lasten reduceras, dock kräver det att taket har möjlighet att flexa under själva lastfallet. Då stötkraften minskar medför det att spänningarna i skyddstakets komponenter också minskar vilket ger en reducerad kvarstående deformation i konstruktionen.

    Konceptet som tagits fram består av en takkassett som är monterad i skyddstakets sidostolpar genom leder som möjliggör rotation. Takkassetten hålls uppe med hjälp av två tvärbalkar som är monterade mellan takkassetten och infästningarna i stativet där tvärbalkarna dämpas av hydrauliska stötdämpare. Även tvärbalkarnas båda infästningar sker genom roterande leder.

  • 46.
    Wirell, Viktoria
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Påverkan av förnybar energi på Singapores energisäkerhet2014Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

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

  • 47.
    Klasson, Hanna
    et al.
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Knopp, Lisa
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Mannegren, Tina
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Rilegård, Andreas
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Sjödin, Johan
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Design och konstruktion av ett småskaligt solvärmesystem2014Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport kommer att behandla konstruktion och design av ett småskaligt portabelt solvärmesystem. Rapportens första del är en teoretisk referensram som ligger till grund för byggandet av en prototyp av den behandlade solvärmetypen som har testats för att se vilken prestanda som uppnåtts och hur systemet förhåller sig till en given målfunktion. Prototypen togs fram med hjälp av produktutvecklingsmetodik, vilken även finns utförligt förklarad i rapporten. Verkningsgraden för den byggda prototypen beräknades efter tester till 65 % och är dimensionerad för 70 liter vatten. Solvärmesystemet som uppvärmningsalternativ och dess konkurrenskraft bland andra uppvärmningsalternativ har också studerats och slutsatsen dragits att solvärme har många miljömässigt positiva aspekter men lång pay off-tid per utvunnen kWh vilket gör att det kan anses som ett mindre attraktivt alternativ i Sverige jämfört med länder med högre solinstrålning.

  • 48.
    Henryson, Kajsa
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, The Institute of Technology.
    Beräkning av växthusgasutsläpp vid odling av raps för biodieselproduktion: Tillämpning av EU:s förnybartdirektiv för alternativa jordbruksmetoder2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Rapsmetylester (RME), även kallat biodiesel, är ett biobränsle som produceras av rapsolja. Trots att RME är förnybart är växthusgasutsläppen i ett livscykelperspektiv inte försumbara, eftersom odlingen av raps ger upphov till utsläpp. Jordbruket är en av Sveriges största källor till klimatpåverkande gaser. Utsläppen sker framförallt i form av den högpotenta äxthusgasenlustgas som härrör från produktion och användning av gödsel, men även utsläpp som beror på användning av fossila bränslen är signifikanta. År 2009 antogs EU-direktivet 2009/28/EG, som bland annat syftade till att säkerställa de förnybara bränslenas klimatprestanda, det så kallade förnybartdirektivet. I detta direktiv anges kriterier för att biodrivmedel och flytande biobränslen ska få klassas som förnybara, framförallt krav på växthusgasutsläppen i bränslets livscykel. Direktivet innefattar även riktlinjer för hur dessa växthusgasutsläpp ska beräknas. Kriterierna har inneburit ett incitament för att förbättra klimatprestandan hos biobränslen. För att minska sin klimatpåverkan och beroende av fossila bränslen har tre gårdar i Östergötland ändrat sina odlingsmetoder. Förändringarna innebär att dieseln för drift av jordbruksmaskiner och in- och uttransporter bytts ut mot biodiesel (RME), att torkningen av skörden nu sker med trädbränslen istället för olja, samt att en del av handelsgödseln ersatts av organiskt gödsel. Gårdarna har själva myntat begreppet Östgötamodellen, som beskriver ett odlingssystem där de fossila bränslena bytts ut mot förnybara, och ibland även andra alternativa jordbruksmetoder tillämpas. Om den raps som odlas enligt Östgötamodellen sedan används som råvara för biodieselproduktion påverkar det bränslets klimatprestanda.

    Syftet med denna studie är att beräkna växthusgasutsläppen från odling av raps enligt Östgötamodellen, jämfört med konventionellt odlad raps. Eftersom rapsen ska användas till att producera biodiesel har beräkningarna gjorts genom att tillämpa riktlinjerna för beräkning som anges i EU:s förnybartdirektiv. Metodiken som beskrivs har ett livscykelperspektiv, och kan beskrivas som en förenklad livscykelanalys. Beräkningarna visar att byte av bränsle till förnybara alternativ ger en minskad klimatbelastning på knappt 6 % i odlingsledet. Att ersätta drygt 20 % av handelsgödseln med slam gav drygt 30 % högre utsläpp från odlingen, medan reducerad jordbearbetning gav en något lägre utsläppsreduktion än användning av förnybara bränslen. Förutom utsläppen får även utsläppsbesparing räknas med för vissa åtgärder som ger ökad kolinlagring i jorden och därmed förhindrar utsläpp av koldioxid. I denna studie har kolinlagring inkluderats för reducerad jordbearbetning, vilket gav en inlagring motsvarande 9051 g CO2eq/kg raps, jämfört med odlingsutsläppen 434 g CO2eq/kg raps. Denna stora inlagring är orimligt hög jämfört med tidigare studier. Dessutom visar tidigare studier att även slam har en hög kolinlagringspotential, trots att slam för närvarande inte täcks in av definitionerna i riktlinjerna för beräkningen. Vidare konstateras att Östgötamodellen inte minskar lustgasutsläppen, som är de utsläpp som kraftigt dominerar växthusgasutsläppen från rapsodlingen. Den enda möjligheten att minska de beräknade lustgasutsläppen enligt den rekommenderade metoden är dock att minska mängden applicerad kvävegödsel per mängd raps, vilket begränsar möjligheterna att tillgodoräkna sig andra åtgärder som minskar lustgasutsläppen.

    Förutom beräkningsmetoderna för kolinlagring och lustgasutsläpp så synliggör denna rapport många av de problem som uppmärksammats i tidigare studier. Framförallt handlar det om att riktlinjerna är otydliga och begränsande, vilket i många fall leder till missvisande resultat. Det innebär att resultaten ska tolkas med försiktighet.

  • 49.
    Hörlin, Jesper
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Jensen, Martin
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    The effect of building energy saving apartment blocks2014Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Att bygga energieffektiva bostäder blir idag allt viktigare. Grunden till detta arbete ligger i vårt intresse för energismart byggande och företagens nyfikenhet över huruvida de lyckats bygga energismart. Syftet med denna undersökning är att jämföra energiförbrukning för två principiella tillvägagångssätt att bygga flerbostadshus, som passiv- eller lågenergihus. De frågor som valts att behandla är:  Vad krävs för att ett hus ska klassas som ett passivhus respektive lågenergihus år 2009?  Klarar respektive konstruktion målet för energiförbrukning?  Vilka faktorer påverkar skillnaden i den specifika energiförbrukningen?  Vilken typ av koncept rekommenderas? Utifrån en teoretisk referensram inom området och tillhandahållet material, såsom ritningar och uppgifter om energiförbrukning, har en jämförelse mellan dessa två olika konstruktioner gjorts. Studien har riktat in sig på att studera parametrar som specifik energiförbrukning per Atemp och bidragande faktorer till en mer eller mindre lyckad energiförbrukning.

  • 50.
    Karczmarz, Veronika
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Thermal comfort in young broiler chickens (Gallus gallus domesticus) inferred from metabolic expenses.2014Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The thermoneutral zone (TNZ) curve lies between the ambient temperatures (Ta) where an endothermic animal uses the least amount of energy to maintain a balance between the heat production from the animal’s own metabolism and the heat lost to the environment. If the animal is exposed to Ta’s over the upper critical temperature (UCT), which is the highest temperature that is still in the TNZ, the animals have to use energy to cool down. If they are exposed to temperatures lower than the lower critical temperature (LCT), which is the lowest temperature that is still in the TNZ, the animal have to use energy to warm up. In the present study oxygen consumption was measured at different Ta’s to determine the TNZ in two and three week old broiler chickens (Gallus gallus domesticus). Two different protocols were used and compared, a pseudorandom protocol in which chickens were exposed to seven temperatures in two hour periods for each run and a more typical progressive protocol in which Ta decreased gradually, one or two degrees per hour. The TNZ in two weeks old chickens was between 30.7 ˚C- 36.4 ˚C and between 28.8 ˚C- 32.7 ˚C in the three weeks old chickens. In chickens the TNZ shifts remarkably during the first few weeks of life towards lower temperatures as the animals acquire thermoregulatory competence. The method with a pseudorandom protocol takes more factors, like activity, into consideration than a typical progressive protocol.

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