Militära insatser i urban miljö kommer troligen att öka alltmer. Detta kräver soldater till fots eftersom dessa lättare kan förflytta sig via och mellan byggnader. Varje deltagande soldat kommer att behöva egen radioutrustning. Då stadsmiljö är ett relativt outforskat område vad gäller militär radiokommunikation är det viktigt att öka förståelsen för radiovågors utbredning i stadsmiljö. Härtill har institutionen för Informationsöverföring på FOI köpt in programmet Radiowave Propagation Simulator (RPS). RPS används i det här examensarbetet för att genomföra en beräkning för ett statiskt scenario, och till beräkningen infoga påverkan från sändares och mottagares mobilitet. Detta utförs genom att rumsligt extrapolera kanalens impulssvar till att gälla i andra positioner än de ursprungligen var beräknade för. Kanalens impulssvar blir då modifierat så att impulssvarets utbredningsvägar får nya fördröjningstider och dess komplexa signal får ny fas. Metoden, som har tagits fram i det här arbetet, för den rumsliga extrapoleringen har implementerats och utvärderats för ett litet scenario. Det extrapolerade resultatet har sedan jämförts med beräknade resultat från RPS. Analysen visade att metoden ger ett tillförlitligt resultat. Ett annat syfte med examensarbetet har varit att visa hur forskningsresultat (från radiokanalen) kan användas effektivare för att ge högre kvalité på forskningsresultat, både på länk- och på nätnivå.

A finite element model has been developed to simulate the forming of a channel section profile with the roll forming method. The model has been optimized to experimental results with respect to strains at the edge of the sheet and spring back of the sides of the profile. Finite element models with a coarse mesh have been compared to models with a finer mesh. The models with to fine mesh become instable and a model with a rather coarse mesh was finally chosen. Both the models with shell elements and the models with solid elements have been used in the simulations. The simulations with shell elements gave very good results both for the geometry shape and the strains at the edge of the sheet. The reaction forces at the tools found in the simulations was only half of the reaction forces fond in the experiments. The simulations with the solid element model showed very good results for the reaction forces while the geometry shape of the sheet was really bad. The spring back was much larger in the simulations than in the experiments. The shell element model was chosen because of the excessive spring back with the solid element model. The spring back of the sides of the sheet differs only a few percent between the simulation and the experiment results when using the shell element model. The reaction forces at the tools in the simulation are only half of the reaction forces measured in the experiments but the results from the simulations are linearly proportional to the results in the experiments. The model that finally was chosen describe both the spring back and the strains at the edge of the sheet very well. Like in the experiments there were no signs of wrinkles at the sheet in any of the simulations.

<p>Examensarbetets problemområde är relativt nytt och outforskat vilket gör det desto mer aktuellt. Supply chain simuleringsverktyg är en kombination av supply chain verktyg och simuleringsverktyg. Denna kombination erbjuder nya undersöknings- och planeringsmöjligheter för företag och blir ett nytt verktyg för företagen att stärka dess konkurrenskraft.</p><p>I examensarbetet utreds om simulering är ett lämpligt verktyg att använda för att påvisa fördelar vid beslut om att flytta företag eller delar av dess verksamhet. För att besvara frågeställningen har en litteraturstudie, intervjuer med tre handelsföretag samt simuleringar genomförts.</p><p>För varje företag har dess beslutsprocess vid lokaliseringsfrågor sammanställts. Utifrån dessa sammanställningar har sedan en generell simuleringsmodell tagits fram. På denna simuleringsmodell har ett antal olika strategier, vilka bygger på intervjusammanställningarna, simulerats och jämförts. Simuleringsresultaten och intervjuresultaten har analyserats och en uppföljning av dessa resultat har sedan gjorts med ett av de intervjuade företagen. Uppföljningen ska styrka simulerings- och intervjuresultaten.</p>

<p>To be able to evaluate different radio waveforms in a laboratory environment FOI in Linköping has developed an experimental system for radio communication called Rasmus. The system consists of a transmitter, a channel emulator and a receiver. The transmitter modulates a digital signal to a desired analogue waveform. The channel emulator is used to simulate a real radio channel. The channel emulator distorts the signal by splitting it up in several propagation paths. Each path has its own statistical distribution, delay and so on. The receiver digitises the signal and saves it in a memory. Analysis of the signal is performed in non-real time. The system has some limitations concerning signal bandwidths and channel models. </p><p>This Master Thesis deals with the problem of scaling the radio channel (with respect to noise, Doppler shift and fading) in order to examine signals that have properties outside the normal operation of the Rasmus system. </p><p>The radio channel studied is a Rayleigh fading channel with two independent propagation paths. A differentially modulated QPSK signal is used as input to the channel. The signal is filtered through root-raised-cosine filter in the transmitter and receiver to reduce the effect of inter-symbol interference. </p><p>Theoretical calculations result in a method, that describe which parameters that should be scaled and how they should be scaled. Simulations are carried out in order to verify the method.</p>

<p>At the department of Electronic Warfare Assessments at the Swedish Defence Research Agency in Linköping one of the activities is modelling and simulation of the duel between a robot and a target. The aim with this Master's thesis is to develop a simulation model of an hovering helicopter. </p><p>First a theoretical description of the forces and moments acting on an helicopter is given. Then the equations of motion are derived. These equations are simplified to be valid only for a hovering helicopter and the result is a mathematical model. </p><p>The mathematical model is the basis for the design of a regulator, whos task is to bring the helicpoter to equilibrium and keep it hovering. Two different regulators are implemented and tested for several cases when different disturbances are acting on the helicopter. </p><p>The matemathical model and one of the regulators are implemented in a simulation program and the results of the simulations are visualized in a graphical interface.</p>

<p>This master thesis was made at the Institute of Technology Stockholm and is a part of a robot hand project called 10-X with the aim to develop a low-cost robot hand that is light and strong.</p><p>The project specification is to further improve the ability to control the robot hand in a user friendly way. This has been done by implementing a controller, earlier used and developed at KTH, which is intuitive and easy to customize after the needs in different kinds of grasps. To make the controller easy to use an user interface has been made.</p><p>Before the implementation of the controller was made on the real hand it was tested and development on a simulation created in MATLAB/simulink with help from a graphic physics engine called GraspIt! The movement of the robot finger is effected of the force from a leaf spring and a tendon that bends the finger. Also the finger is exposed of contact forces and all these components had to be modeled in the simulation to make the finger act properly.</p> / <p>Detta examensarbete är genomfört på KTH Stockholm och är en del av ett projekt, kallat 10-X, vars syfte är att utveckla och ta fram en robothand som är lätt och stark samtidigt som den är billig.</p><p>Projektets målsättning är att vidare förbättra och utveckla möjligheten att kontrollera robothanden på ett användarvänligt sätt. Detta har gjorts genom att implementera en regulator, tidigare utvecklad och använd på KTH, som är instruktiv och lätt att anpassa efter olika typer av grepp. För att göra regulatorn enkel att använda har ett användargränssnitt skapats.</p><p>Innan regulatorn implementerades på den riktiga robothanden utvecklades och testades den på en simuleringsmodell, skapad i MATLAB/simulink med hjälp av en grafisk fysikmotor GraspIt! Rörelsen hos ett robotfinger påverkas av krafter från en bladfjäder och den lina som böjer fingret. Fingret utsätts också för kontaktkrafter och alla dessa komponenter blev modellerade i simulatorn för att få fingret att bete sig korrekt.</p>

<p>During the most recent decades modern equation-based object-oriented modeling and simulation languages, such as Modelica, have become available. This has made it easier to build complex and more detailed models for use in simulation. To be able to simulate such large and complex systems it is sometimes not enough to rely on the ability of a compiler to optimize the simulation code and reduce the size of the underlying set of equations to speed up the simulation on a single processor. Instead we must look for ways to utilize the increasing number of processing units available in modern computers. However to gain any increased performance from a parallel computer the simulation program must be expressed in a way that exposes the potential parallelism to the computer. Doing this manually is not a simple task and most modelers are not experts in parallel computing. Therefore it is very appealing to let the compiler parallelize the simulation code automatically. This thesis investigates techniques of using automatic translation of models in typical equation based languages, such as Modelica, into parallel simulation code that enable high utilization of available processors in a parallel computer. The two main ideas investigated here are the following: first, to apply parallelization simultaneously to both the system equations and the numerical solver, and secondly. to use software pipelining to further reduce the time processors are kept waiting for the results of other processors. Prototype implementations of the investigated techniques have been developed as a part of the OpenModelica open source compiler for Modelica. The prototype has been used to evaluate the parallelization techniques by measuring the execution time of test models on a few parallel archtectures and to compare the results to sequential code as well as to the results achieved in earlier work. A measured speedup of 6.1 on eight processors on a shared memory machine has been reached. It still remains to evaluate the methods for a wider range of test models and parallel architectures.</p>

<p>The purpose of this thesis was to analyse, model and finally generate dynamic vehicular motions in a train. The objective with the analysis was to find important motions for a realistic train experience. The motions from the analysis were then weighted against possibilities for generation in a motion platform.A dynamic motion model was created to model the selected motions. The model was implemented in a simulation environment, more specifically MATLAB/Simulink. The simulation environment was used to simulate the model and to generate outputs to control a motion platform. The motions of the motion platform depended on how the modelled motions were chosen to be generated. The motion model was validated by comparison of results from the model and measured values from a real train.Generation of motions was accomplished by implementation of the model in a motion platform. A virtual test track was constructed and used to test how the implemented model controlled the motion platform. The experience of the test track in the motion platform was evaluated by persons in a cabin mounted on the motion platform.</p> / <p>Syftet med detta examensarbete var att analysera, modellera och slutligen återskapa ett tågs fordonsdynamiska rörelser. Rörelserna har analyserats med utgångspunkt från vad som ansågs viktigt att återskapa för att en människa ska få en realistisk tågupplevelse. Resultatet från rörelseanalysen vägdes mot möjligheter till återskapande i ett rörelsesystem. En dynamisk rörelsemodell skapades för att modellera de valda rörelserna. Modellen byggdes upp i en simuleringsmiljö, närmare bestämt MATLAB/Simulink. Där kunde modellen simuleras och förses med utsignaler till styrning av ett rörelsesystem. Vilka rörelser som rörelsesystemet skulle utföra berodde på hur de modellerade rörelserna valdes att återskapas. Rörelsemodellen validerades genom att jämföra resultaten från modellen med mätdata från ett verkligt tåg. Återskapande av rörelser gjordes genom implementering av modellen i ett rörelsesystem. Ett virtuellt testspår konstruerades och användes som test av hur den implementerade modellen styrde rörelsesystemet. Utvärdering av hur testspåret upplevdes i rörelsesystemet gjordes genom att personer fick sitta i en kabin på rörelsesystemet.</p>

<p>Value-at-Risk (VaR) is among financial institutions a commonly used tool for measuring market risk. Several methods to calculate VaR exists and different implementations often results in different VaR forecasts. An interesting implementation is historical simulation, and the purpose of this thesis is to examine whether historical simulation with dynamic volatility updating is useful as a model to calculate VaR and how this differs in regard to type of asset or instrument. To carry out the investigation six different models are implemented, which then are tested for statistical accuracy through Christoffersens test. We find that incorporation of volatility updating into the historical simulation method in many cases improves the model. The model also generates good results compared to other commonly used models, especially if the volatility is predicted through a GARCH(1,1) updating scheme.</p> / <p>Value-at-Risk (VaR) är ett bland finansiella institutioner vanligt mått för att mäta marknadsrisk. Det finns ett flertal olika sätt att beräkna VaR, vilka ofta ger olika resultat beroende på förutsättningar. Ett av dessa är historisk simulering, och syftet med denna uppsats är att undersöka huruvida historisk simulering med dynamiskt uppdaterande volatilitet är en användbar modell för beräkning av VaR och hur dess lämplighet beror på valt tillgångsslag eller instrument. För att besvara detta implementeras sex olika modeller för beräkning av VaR, vilka sedan testas med hjälp av Christoffersens test. Vi finner att inkorporering av dynamisk volatilitet i historisk simulering i många fall medför en förbättring av modellen ifråga om statistisk riktighet. Vidare kan historisk simulering med dynamiskt uppdaterande volatilitet anses vara konkurrenskraftig i jämförelse med andra vanligt använda modeller, framförallt då volatiliteten skattas genom GARCH(1,1).</p>

<p>Many traffic incidents are due to the driver’s lack of attention, resulting in dangerous lane departures, either sliding off theroad or into the oppose lane. These kinds of incidents often have serious outcomes, which has led to much effort being concentrated on preventing or lessening the damages when the incident is already a fact, for example by installing safety belts and air bags. These measures may be considered to be acts of so-called passive safety. </p><p>Active safety on the other hand, means that the safety systems intervene before the incidents have occurred. Lane Keeping Aid (LKA), which has been developed and implemented in this master thesis project, is a system designed to support the driver in the lateral axis in situations when unwanted lane departure is an evident risk. </p><p>To be able to determine when the system should intervene and support the driver, information regarding how the driver handles the vehicle, along with the vehicle’s position and direction in the lane, is essential. The car’s position may be obtained by installing a camera in the vehicle. The information needed regarding other things, e.g. the car’s position in relation to the lane, is obtained by using a Kalmanfilter, which is based on a physically developed model, and which estimates the mentioned distances. Based on measurements and estimated values, it is possible for the LKA system to calculate an assistance torque, aimed at decreasing the lateral deviation from the centre of the lane. An electric power steering, instead of a conventional hydraulic steering servo is then used to produce the torque. </p><p>The LKA system has been developed in a simulation environment using Simulink before being implemented, in order to monitor the function of the system before beginning actual testdrives. Furthermore, real measurement data given at driving with the test vehicle has been used to adjust and test the function. </p><p>The results from the project’s first phase, in the simulation environment, show that the estimated values from the Kalmanfilter correlates well with real test data. Simulations with real measurement data show that the system functions as intended. </p><p>Finally, it may also be mentioned, that the system has yet not been fully tested in a vehicle equipped with an electric power steering, which ought to be included in future development of the system.</p>