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Polarization characteristics in polyelectrolyte thin film capacitors : Targeting field-effect transistors and sensorsLarsson, Oscar January 2009 (has links)
<p>Polymers are very attractive materials that can be tailored for specific needs and functionality. They can for instance be made electrically insulating or (semi)conducting, with specific mechanical properties. Polymers are often processable from a solution, which enables the use of low-cost manufacturing techniques to fabricate polymer devices. Polymer-based electronic and electrochemical devices and sensors have been developed.</p><p>This thesis is related to the polarization characteristics in polyelectrolyte thin film capacitor structures. The polarization characteristics have been analyzed at various humidity levels for polyelectrolyte capacitors alone and when incorporated as the gate-insulating material in polyelectrolyte-gated organic field-effect transistors. Both limitations and possibilities of this class of transistors have been identified. Also, a concept for wireless readout of a passively operated humidity sensor circuit is demonstrated. The sensing mechanism of this sensor is related to the polarization in a polyelectrolyte thin film capacitor. This sensor circuit can be manufactured entirely with common printing technologies of today and can be integrated into a low-cost passive sensor label.</p>
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Methods for Visually Guided Robotic Systems : Matching, Tracking and ServoingLarsson, Fredrik January 2009 (has links)
<p>This thesis deals with three topics; <em>Bayesian tracking, shape matching</em> and <em>visual servoing</em>. These topics are bound together by the goal of visual control of robotic systems. The work leading to this thesis was conducted within two European projects, COSPAL and DIPLECS, both with the stated goal of developing artificial cognitive systems. Thus, the ultimate goal of my research is to contribute to the development of artificial cognitive systems.</p><p>The contribution to the field of Bayesian tracking is in the form of a framework called Channel Based Tracking (CBT). CBT has been proven to perform competitively with particle filter based approaches but with the added advantage of not having to specify the observation or system models. CBT uses channel representation and correspondence free learning in order to acquire the observation and system models from unordered sets of observations and states. We demonstrate how this has been used for tracking cars in the presence of clutter and noise.</p><p>The shape matching part of this thesis presents a new way to match Fourier Descriptors (FDs). We show that it is possible to take rotation and index shift into account while matching FDs without explicitly de-rotate the contours or neglecting the phase. We also propose to use FDs for matching locally extracted shapes in contrast to the traditional way of using FDs to match the global outline of an object. We have in this context evaluated our matching scheme against the popular Affine Invariant FDs and shown that our method is clearly superior.</p><p>In the visual servoing part we present a visual servoing method that is based on an action precedes perception approach. By applying random action with a system, e.g. a robotic arm, it is possible to learn a mapping between action space and percept space. In experiments we show that it is possible to achieve high precision positioning of a robotic arm without knowing beforehand how the robotic arm looks like or how it is controlled.</p>
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Topics in Spectrum Sensing for Cognitive RadioAxell, Erik January 2009 (has links)
<p>Cognitive radio is a new concept of reusing licensed spectrum in an unlicensed manner. Cognitive radio is motivated by recent measurements of spectrum utilization, showing unused resources in frequency, time and space. The spectrum must be sensed to detect primary user signals, in order to allow cognitive radios in a primary system. In this thesis we study some topics in spectrum sensing for cognitive radio.</p><p>The fundamental problem of spectrum sensing is to discriminate samples that contain only noise from samples that contain a very weak signal embedded in noise. We derive detectors that exploit known structures of the signal, for the cases of an OFDM modulated signal and an orthogonal space-time block coded signal. We derive optimal detectors, in the Neyman-Pearson sense, for a few different cases when all parameters are known. Moreover we study detection when the parameters, such as noise variance, are unknown. We propose solutions the problem of unknown parameters.</p><p>We also study system aspects of cognitive radio. More specifically, we investigate spectrum reuse of geographical spectrum holes in a frequency planned primary network. System performance is measured in terms of the achievable rate for the cognitive radio system. Simulation results show that a substantial sum-rate could be achieved if the cognitive radios communicate over small distances. However, the spectrum hole gets saturated quite fast, due to interference caused by the cognitive radios.</p>
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Designing Emergency Management Training Sessions for C3Fire – Prioritization & Information SearchingArshad, Muteer, Pervaiz, Tehman January 2009 (has links)
<p>C3Fire is an emergency management system. The purpose of this simulation system is to develop teamdecision making skills and to provide an opportunity for researchers to perform research in a controlledenvironment. Training is a crucial task for developing skills to tackle with emergency situation. Thepurpose of this thesis is to develop decision making by keeping focus on two major areas, namely;making prioritizations and information searching using UAV & Non UAV.</p><p>Success of dealing withemergency management situation mostly depends on these training factors.The methodology which we adapt to achieve these two training goals are as follow; first we designtraining sessions based on the literature study and research work. These training sessions are fullycapable of achieving desired goals (i.e. prioritization & information searching). Finally we test thesession by playing game with the participants from the real life.</p><p>In this thesis, theory part discusses literature about C3Fire and theoretical framework explains differentterminologies and methods used in emergency management. Training sessions and their analysis isexplained using theoretical framework. Better ways of communication and prioritization while takingdecisions in emergency situation are discussed.</p><p><strong>Keywords:</strong> C3Fire, Simulation System, Micro World, Teamwork, Situational Awareness, OODA,Prioritization, Information Searching, UAV, Non-UAV</p>
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Hur elpris och värmelast påverkar fjärrvärmesystem : fallet Göteborg Energi och Volvo CarsAlsbjer, Markus January 2009 (has links)
<p>Rapporten betraktar energisystemen vid Göteborg Energi (GE) och Volvo Cars, Torslanda. De två systemen integreras som ett system och inverkan av olika åtgärder betraktas. Huvudsyftet är att minska systemkostnaden för det totala systemet.</p><p>Arbetet är genomfört med kraftbonusmetoden, en marginalsyn på el där all ny elproduktion beräknas ersätta kolkondensproducerad el. Allokeringen för utsläpp vid kraftvärmeproduktion är också beräknad med kraftbonusmetoden.</p><p>För simulering har optimeringsprogrammet Modest använts. En konstruktion av datormodeller av energisystemen vid Göteborg Energi och Volvo Cars har gjorts. Systemen kan kopplas mot varandra och hur åtgärder som introduceras på det ena systemet påverkar det andra kan studeras.</p><p>Åtgärder som studerats med hjälp av simuleringsmodellerna:</p><ul><li>Elpris höjt till europeisk nivå</li><li>En sammankoppling av fjärrvärmenäten vid Volvo Cars och Göteborg Energi</li><li>Fjärrvärmekonverteringar vid Volvo Cars</li></ul><p>Viktiga slutsatser av arbetet:</p><ul><li>Höjt elpris både ökar vinsten ordentligt och minskar de globala utsläppen för energisystem med både el- och värmeproduktion</li><li>Sammankoppling av två system är ekonomiskt lönsamt då de ligger nära varandra</li><li>Fjärrvärmekonverteringar på Volvo lönar sig inte ekonomiskt i dagsläget men blir betydligt mer intressant om elpriset i Sverige ökar till europeiskt elpris</li><li>Det räcker med att det svenska elpriset ökar till dagens europeiska nivå för att skuggpriset på fjärrvärme skulle bli negativt under sommarmånaderna. Detta under förutsättning att ett kraftvärmeverk ligger på marginalen för värmeproduktion</li></ul> / <p>This report observes the energy systems at Göteborg Energi and Volvo Cars, Torslanda. The systems are integrated as one system and the influence of different measures is evaluated. The main purpose is to reduce the total cost of the integrated system.</p><p>This work use the power bonus method, a margin perspective view where all additional electricity production is calculated to replace condense power. The allocation for emissions at a combined heat and power plant is also calculated with the power bonus method.</p><p>The data is simulated with the optimisation program Modest. Using computer models for the energy systems at Göteborg Energi and Volvo Cars the systems have been connected. The results from measures on one of the systems can be evaluated in the complete system.</p><p>Evaluated measures using the computer models:</p><ul><li>Electricity price raised to European levels</li><li>A connection between the district heating networks at Göteborg Energi and Volvo Cars</li><li>Conversions to district heating in Volvo Cars network</li></ul><p>Important conclusions in this report:</p><ul><li>Raised electricity prices increases the profit vastly and reduces the global emissions for energy systems with combined heat and power production</li><li>Connecting two nearby district heating networks is profitable</li><li>Conversions to district heating at Volvo Cars is not profitable in the present situation but gains interest if electricity prices in Sweden increases to a European level</li><li>An electricity price on the present European level is enough to make the shadow prices for heat negative during the summer months if a combined heat and power plant is on the margin for heat production</li></ul>
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Kapacitetsanalys av CFB-pannan vid SCA Packaging Munksund AB / Capacity analysis of the CFB-boiler at SCA Packaging Munksund ABElvemo, Kristian January 2009 (has links)
<p>Kraftvärmeverket vid SCA Packaging Munksund AB är ett samarbete mellan SCA och Vattenfall och det består av en ångpanna av typen cirkulerande fluidiserad bädd som togs i drift 2001. Man vill nu genomföra en undersökning om CFBpannans prestanda har förändrats sedan starten, samt en undersökning av pannans maximala kapacitet. Examensarbetet har då bestått av att utföra ett prestandaprov samt ett prov för maximal kapacitet. Arbetet har även innefattat att utarbeta en algoritm för att fiktivt beräkna ingående bränslets fukthalt via rökgasparametrar.</p><p>CFB-pannan är dimensionerad mot en termisk effekt på 98MW, vid en bränslekvalitet på 55 % fukthalt och värmevärdet 7,3 MJ/kg. Vid denna driftpunkt garanterar panntillverkaren Foster Wheeler en verkningsgrad på minst 90,57 %. Prestandaprovet från 2002 visade på en verkningsgrad på 91,1 %. Resultatet från dessa observationer visade på en verkningsgrad på 92,07 %, att notera är att bränslekvaliteten legat på fukthalten 50 % och värmevärdet 8,48 MJ/kg.</p><p>Vid framtida produktionsökningar i pappersbruket kommer man samtidigt behöva öka produktionen av processånga. Man har sedan tidigare drifterfarenheter påpekat att man har haft problem med pannans luft/rökgassytem vid höga laster. Resultatet från maxkapacitetstesterna var att pannan primärt begränsas av kvaliteten på bränslet, då detta sätter en begränsning på hur mycket energi som finns tillgängligt. Processmässigt så blev resultatet att motorn till rökgasfläkten samt sandåterföringen var de begränsande enheterna. Vid testet var bränslefukthalten 45 % och man uppnådde då ett ångflöde på 146 ton/h. Det kom även fram att sekundärfläkten inte körts enligt panntillverkarens rekommenderade motorhastighet på 1765 varv/min, den aktuella inställningen har ett synkront varvtal på 1500 varv/min.</p><p>Att utreda hur mycket effekt som dessa begränsningar låser fast har varit oerhört svårt att ge svar på, och vad gäller tidsramen för arbetet så har det inte kunnat grävas djupare i denna problemställning. En teoretisk analys har däremot utförts på maximal kapacitet vid olika bränslefukthalter, se Figur 33 och Figur 34 på sidan 78. Dessa figurer belyser hur viktig kvaliteten på bränslet är för att pannan skall kunna ha en möjlighet att leverera en hög last. Då hanteringen av bränslet för att minimera kvalitetsförluster är något man kan påverka med enklare metoder, är rekommendationen att man startar en projektgrupp som ser över bränslehanteringen för att minimera kvalitetsförluster vid egen kortvarig lagring.</p> / <p>The combined heat and power plant at SCA Packaging Munksund AB is a collaboration between SCA and Vattenfall and it consists of a steam boiler with a circulating fluidized bed which was taken in to service in 2001. Today the company wants to make an evaluation about if there is any changes in the CFPboilers performance since the start, they would also like an evaluation about the maximum capacity. The examination work has then been about executing a performance test and a maximum capacity test. The work has also included the construction of an algorithm that would fictively calculate the content of moisture for the in fed biofuel through the fluegas parameters.</p><p>The CFB-boiler is dimensioned to have a thermal effect of 98 MW, with the quality of the biofuel having a content of moisture at 55 % and the heating value of 7,3 MJ/kg. At this operation point the boiler constructor guarantees an efficiency of 90,57 %. Evaluations made in 2002 concluded an efficiency at 91,1 %. The results from this report showed an efficiency at 92,07 %, one should then note that the biofuel quality then had a content of moisture at 50,05 % and a heating value at 8,48 MJ/kg.</p><p>Future increases in the mills production will mean that they also need to increase the steam production as well. From earlier experiences with the boilers capacity, operators have countered problems with the air/fluegas-system at high loads. The primary result from the maximum capacity test is that the quality of the biofuel sets the limit for how well the boiler can perform. The secondary results indicate that the motor for the fluegasfan and that the bedmaterialreentrysystem are the narrow sections. For the test the contest of moisture was 45 % and the produced steam reached 146 ton/h. Something else that surfaced during the report was that the motor for the secondary air fan was not running at the boiler manufacturer dimensioned speed at 1765 rpm, the actual settings had a maximum synchronous speed at 1500 rpm.</p><p>To investigate how much production capacity that is tied up in the narrow sections is extremely difficult to answer, the timeframe for the report limited the digging for an answer for this question. Instead a theoretical analysis was made on the maximum capacity from a perspective of different contests of moisture for the biofuel, watch Figur 33 and Figur 34 on page 78. These figures cast a light on the importance on the quality of the biofuel, so that the boiler has the ability to deliver high loads. Handling of the biofuel to minimize the loss of quality is something that can be affected with relatively simple methods, the recommendation is that a project group is started that looks over the handling of the biofuel to minimize the quality losses during short time storage.</p>
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Handling of Environmental Related Requirements : Awareness and Ability to Act at Small and Medium Sized Electric and Electronic CompaniesLin, Han-Hsuan January 2008 (has links)
<p>Environmental related product requirements are increasing worldwide from government authorities, customers and other stakeholders. For small and medium sized companies manufacturing electric and electronic products it is more difficult compared to bigger companies to meet new product related requirements due to smaller budget, resources and knowledge. This research studies the awareness and ability to act upon changes when small and medium sized companies in Sweden face environmental related requirements.</p><p>The result is compared to previous conducted studies in a number of Asian countries. The study has been conducted through face-to-face interviews (12 companies), phone interviews (6 companies), and questionnaires (50 companies). After a preliminary literature study and targeting of objective companies interviews were made at first with the questionnaire study based on results from the interviews. In total, respondents from 68 companies participated in this research. Results from the study reveal that companies both in Sweden and Asia experience the same directives from EU and that WEEE and RoHS have had the biggest impact upon companies. Outside the EU market, companies do not comply with the legislations in the same way. There is a difference in how Swedish companies choose to treat environmental related product requirements as compared to electric and electronic companies in Asia. Furthermore, legislations are a very effective form to affect companies’ environmental work and adaptations, especially if it is imposed directly on the product itself. Both Swedish and Asian companies feel they need more education, more information about environmental related product requirements and more support from government authorities in order to cope with increasing demands from customers and legislations.</p>
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Efficient Spatiotemporal Filtering and ModellingKarlholm, Jörgen January 1996 (has links)
<p>The thesis describes novel methods for efficient spatiotemporal filtering and modeling. A multiresolution algorithm for energy-based estimation and representation of local spatiotemporal structure by second order symmetric tensors is presented. The problem of how to properly process estimates with varying degree of reliability is addressed. An efficient spatiotemporal implementation of a certainty-based signal modeling method called normalized convolution is described. As an application of the above results, a smooth pursuit motion tracking algorithm that uses observations of both target motion and position for camera head control and motion prediction is described. The target is detected using a novel motion field segmentation algorithm which assumes that the motion fields of the target and its immediate vicinity, at least occasionally, each can be modeled by a single parameterized motion model. A method to eliminate camera-induced background motion in the case of a pan/tilt rotating camera is suggested.</p>
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Sparse Representations for Medium Level VisionForssén, Per-Erik January 2001 (has links)
<p>In this thesis a new type of representation for medium level vision operations is explored. We focus on representations that are sparse and monopolar. The word sparse signifies that information in the feature sets used is not necessarily present at all points. On the contrary, most features will be inactive. The word monopolar signifies that all features have the same sign, e.g. are either positive or zero. A zero feature value denotes ``no information'', and for non-zero values, the magnitude signifies the relevance.</p><p>A sparse scale-space representation of local image structure (lines and edges) is developed.</p><p>A method known as the channel representation is used to generate sparse representations, and its ability to deal with multiple hypotheses is described. It is also shown how these hypotheses can be extracted in a robust manner.</p><p>The connection of soft histograms (i.e. histograms with overlapping bins) to the channel representation, as well as to the use of dithering in relaxation of quantisation errors is shown. The use of soft histograms for estimation of unknown probability density functions (PDF), and estimation of image rotation are demonstrated.</p><p>The advantage with the use of sparse, monopolar representations in associative learning is demonstrated.</p><p>Finally we show how sparse, monopolar representations can be used to speed up and improve template matching.</p>
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Reinforcement Learning Using Local Adaptive ModelsBorga, Magnus January 1995 (has links)
<p>In this thesis, the theory of reinforcement learning is described and its relation to learning in biological systems is discussed. Some basic issues in reinforcement learning, the credit assignment problem and perceptual aliasing, are considered. The methods of temporal difference are described. Three important design issues are discussed: information representation and system architecture, rules for improving the behaviour and rules for the reward mechanisms. The use of local adaptive models in reinforcement learning is suggested and exemplified by some experiments. This idea is behind all the work presented in this thesis. A method for learning to predict the reward called the prediction matrix memory is presented. This structure is similar to the correlation matrix memory but differs in that it is not only able to generate responses to given stimuli but also to predict the rewards in reinforcement learning. The prediction matrix memory uses the channel representation, which is also described. A dynamic binary tree structure that uses the prediction matrix memories as local adaptive models is presented. The theory of canonical correlation is described and its relation to the generalized eigenproblem is discussed. It is argued that the directions of canonical correlations can be used as linear models in the input and output spaces respectively in order to represent input and output signals that are maximally correlated. It is also argued that this is a better representation in a response generating system than, for example, principal component analysis since the energy of the signals has nothing to do with their importance for the response generation. An iterative method for finding the canonical correlations is presented. Finally, the possibility of using the canonical correlation for response generation in a reinforcement learning system is indicated.</p>
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