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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Modeling and algorithm adaptation for a novel parallel DSP processor / Modellering och algorithm-anpassning för en ny parallell DSP-processor

Kraigher, Olof, Olsson, Johan January 2009 (has links)
<p>The P3RMA (Programmable, Parallel, and Predictable Random Memory Access) processor, currently being developed at Linköping University Sweden, is an attempt to solve the problems of parallel computing by utilizing a parallel memory subsystem and splitting the complexity of address computations with the complexity of data computations. It is targeted at embedded low power low cost computing for mobile phones, handsets and basestations among many others. By studying the radix-2 FFT using the P3RMA concept we have shown that even algorithms with a complex addressing pattern can be adapted to fully utilize a parallel datapath while only requiring additional simple addressing hardware. By supporting this algorithm with a SIMT instruction almost 100% utilization of the datapath can be achieved. A simulator framework for this processor has been proposed and implemented. This simulator has a very flexible structure featuring modular addition of new instructions and configurable hardware parameters. The simulator might be used by hardware developers and firmware developers in the future.</p>
152

Kranspetsstyrning : en jämförande utvärdering av kranstyrning för skogsmaskiner utförd i simulator / Boomtip Control : a Comparative Evaluation of two Control Systems for Forestry Machines using a Simulator

Egermark, Therese January 2005 (has links)
<p>Syftet med studien var att utvärdera om kranspetsstyrning i skogsmaskiner är ett enklare styrsystem att lära sig från grunden och om arbetsbelastningen värderades lägre, än den konventionella styrningen. Meningen var även att kartlägga skillnader i inlärningsprocessen samt i upplevd arbetsbelastning. Detta krävde konstruktion av mätmetoder för insamling av relevant information. </p><p>Utvärderingen gjordes i enskogsmaskinsimulator vid manövrering av skotare samt genom enkätundersökningar. Studien genomfördes med hjälp av försöksdeltagare från naturbruksgymnasiet Jällaskolan i Uppsala. Övningar och tester utfördes i skogsmaskinsimulatorn. Prestationer dokumenterades med hjälp av färdighetstester och enkäter. </p><p>Resultaten av studien visar tydligt att kranspetsgruppen presterar signifikant bättre i samtliga kategorier som mätts genom tester, med undantag av åtgången tid per test. Avseende tid är kranspetgruppen inte statistiskt säkert bättre, men gruppens förbättringstakt är avsevärt högre än den konventionella gruppen, vars resultat hålls på samma nivå över perioden. Därmed visar studien att kranspetsstyrning i de gjorda testerna är ett enklare system att lära sig från grunden. Kvalitativa undersökningar visade att kranspetsgruppen i genomsnitt värderade arbetsbelastningen av testkörningarna lägre än den konventionella gruppen.</p>
153

Driving Simulator Development and Performance Study

Juto, Erik January 2010 (has links)
<p>The driving simulator is a vital tool for much of the research performed at theSwedish National Road and Transport Institute (VTI). Currently VTI posses three driving simulators, two high fidelity simulators developed and constructed by VTI, and a medium fidelity simulator from the German company Dr.-Ing. Reiner Foerst GmbH. The two high fidelity simulators run the same simulation software, developed at VTI. The medium fidelity simulator runs a proprietary simulation software. At VTI there is a wish to integrate the medium fidelity Foerst Trainer simulator hardware into the VTI simulation software environment. This would increase research, development and maintanance flexibility and simulator availability since development and research could be performed on one additional simulator. Anintegration would lead to a homogenous software environment that also decreasesdevelopment, maintanance and training costs.To integrate the Foerst Trainer simulator and the VTI simulation software to communicate a program that translates and relays input and output between the two was developed. An assessment of the hardware-software integration was performed through an experiment where the high fidelity Simulator 3 and the medium fidelity Foerst Trainer simulator were compared. The experiment was designed to measure the participants driving performances and the perceived realism of the simulator. The results of the experiment shows that there is suprisingly small differences between the simulators, but more research is needed for more conclusive results.</p>
154

Utvärdering och implementering av automatiska farthållare i fordonssimulator

Borst, Rikard January 2006 (has links)
<p>Vehicle simulators are becoming more common in vehicle industries. Company earns lot of money on simulations instead of real tests. Real tests are necessary but not made so extensively as before.</p><p>In this thesis the building of an vehice simulator will be described and a comparison between three different cruise controls. The three cruise controls are PI-regulator, a regulator who regulates after positions in the terrain and a MPC-regulator. The reason for choosing this three is to see the difference between simple regulation and more complex regulation with respect to fuel consumption, travel time and complexity.</p><p>The vehicle simulator is made in Matlab/Simulink, Visual Studio and Open Scene Graph. The facilities needed for runnning the simulator is a relative good computer with a grapics card on at least 128 MB RAM plus a steering wheel and pedals for brake and gas to achieve best feeling. A keyboard can be used but it reduces almost all feeling.</p><p>After several simulations a conclusion was made. The MPC-regulator was the regulator who consumed least fuel and travel time. The regulator who regulates after positions in the terrain was not too far away. It would be interesting to do more research about it. In fact it is only a PI-regulator who makes ``clever'' decisions when a hill with enough slope appears. With enough slope means a downhill where the vehicle can accelerate without the use of fuel and an uphill where the vehicle can not keep its speed with maximum use of fuel.</p><p>A conclusion was stated that the friction and height profile influenced on settings for the PI-regulator and with some adjustments on this settings, fuel could be saved.</p>
155

Integrated Field Modeling

Nazarian, Bamshad January 2003 (has links)
<p>This research project studies the feasibility of developing and applying an integrated field simulator to simulate the production performance of an entire oil or gas field. It integrates the performance of the reservoir, the wells, the chokes, the gathering system, the surface processing facilities and, whenever applicable, gas and water injection systems.</p><p>The approach adopted for developing the integrated simulator is to couple existing commercial reservoir and process simulators using available linking technologies. The simulators are dynamically linked and customized into a single hybrid application that benefits from the concept of open software architecture. The integrated field simulator is linked to an optimization routine developed based on the genetic algorithm search strategies. This enables optimization of the system at field level, from the reservoir to the process. Modeling the wells and the gathering network is achieved by customizing the process simulator.</p><p>This study demonstrates that the integrated simulation improves currentcapabilities to simulate the performance of an entire field and optimize its design. This is achieved by evaluating design options including spread and layout of the wells and gathering system, processing alternatives, reservoir development schemes, and production strategies.</p><p>Effectiveness of the integrated simulator is demonstrated and tested through several field-level case studies that discuss and investigate technical problems relevant to offshore field development. The case studies cover topics such as process optimization, optimum tie-in of satellite wells into existing process facilities, optimal well location, and field layout assessment of a high pressure high temperature deepwater oil field.</p><p>Case study results confirm the viability of the total field simulator by demonstrating that the field performance simulation and optimal design were obtained in an automated process with reasonable computation time. No significant simplifying assumptions were required to solve the system and tedious manual data transfer between simulators, as conventionally practiced, was avoided.</p>
156

Computer Integrated Endoscopic Simulator for Training in Esophagogastroduodenoscopy

Surangsrirat, Decho 29 April 2001 (has links)
We propose a computer integrated endoscopic simulator for training in upper endoscopy as a low-cost alternative to the traditional training methods and virtual reality simulators. The use of a real endoscope in conjunction with our simulator and computer system in an actual operating room setup makes the training environment similar to a real procedure. Endoscopic surgery is the performance of surgery through a small incision with the aid of special medical equipment called a flexible endoscope. The advantage of this technique over open surgery is that there is significantly less operative trauma, resulting in less pain and a shorter recovery time. Side effects of the surgery, such as the risk of infection, are also reduced. While endoscopy procedure has tremendous benefits, surgeons require considerable practice and time to develop competency. Traditionally, the procedure has been taught at the expense of patient comfort and safety, in other words, gastroenterology training fellows have performed the surgery under the supervision of physicians. Patients who undergo the endoscopies performed by fellows, particularly early in the training period, have been more likely to suffer more discomfort and prolonged procedures. In this study, we introduce a new type of simulator which combines the use of mechanical model and computer system as an additional or low-cost alternative for training in upper endoscopy. Our approach is to integrate a computer system with a realistic mechanical model to create a computer-based simulator for upper endoscopy training. The simulator will cover the basics of flexible endoscopy and teach a trainee the skills required to perform upper endoscopy. The mechanical training model with a sensor system that simulates a human upper gastrointestinal tract, including pathologies such as ulcers and polyps, will be built and integrated with computer software. The software offers the following functions: provides help to the trainee, provides curriculum-required learning tasks, and assesses the performance and diagnostic skills. Due to the optical nature of an endoscopic lens, the obtained image suffers from a barrel-type spatial distortion, which results in an inconsistent measurement of object size and distance. Our distortion correction system with automatic calibration, based on least squares estimation, offers a better perception of size and distance from the endoscopic images. In order to examine the endoscopic maneuvering skills of the trainee, the automatic evaluation system is created. The system uses images from the exam procedure to verify the trainee skills. We use Support Vector Machine to classify endoscopic images of different regions in upper gastrointestinal tract. The experimental results on the distortion correction and image classification are reported. Simulator validation survey result from gastroenterology surgeons and fellows is included in this dissertation. A recommendation for further study is also enclosed.
157

Integrated Field Modeling

Nazarian, Bamshad January 2003 (has links)
This research project studies the feasibility of developing and applying an integrated field simulator to simulate the production performance of an entire oil or gas field. It integrates the performance of the reservoir, the wells, the chokes, the gathering system, the surface processing facilities and, whenever applicable, gas and water injection systems. The approach adopted for developing the integrated simulator is to couple existing commercial reservoir and process simulators using available linking technologies. The simulators are dynamically linked and customized into a single hybrid application that benefits from the concept of open software architecture. The integrated field simulator is linked to an optimization routine developed based on the genetic algorithm search strategies. This enables optimization of the system at field level, from the reservoir to the process. Modeling the wells and the gathering network is achieved by customizing the process simulator. This study demonstrates that the integrated simulation improves currentcapabilities to simulate the performance of an entire field and optimize its design. This is achieved by evaluating design options including spread and layout of the wells and gathering system, processing alternatives, reservoir development schemes, and production strategies. Effectiveness of the integrated simulator is demonstrated and tested through several field-level case studies that discuss and investigate technical problems relevant to offshore field development. The case studies cover topics such as process optimization, optimum tie-in of satellite wells into existing process facilities, optimal well location, and field layout assessment of a high pressure high temperature deepwater oil field. Case study results confirm the viability of the total field simulator by demonstrating that the field performance simulation and optimal design were obtained in an automated process with reasonable computation time. No significant simplifying assumptions were required to solve the system and tedious manual data transfer between simulators, as conventionally practiced, was avoided.
158

Design and Development of a Bus Simulator for Bus Driver

Muncie, Helen January 2006 (has links)
The bus industry is plagued by high accident costs and risks of passenger injuries. A bus simulator may offer a method of reducing accident rates by delivering targeted training to bus drivers who are most at risk. The first part of this thesis describes the design of the UK's first bus simulator, the fidelity of which was based on a thorough analysis of bus crashes. The second part describes the first studies in a multi-staged method to evaluate the training effectiveness of the simulator: face validity, effects of bus driver experience and stress on simulated performance and simulator sickness. This approach ensured that the ABS has a reasonable level of fidelity, is capable of eliciting behaviourally valid responses from bus drivers and is the first step is achieving training transfer effectiveness. The final study investigated the occurrence of self-bias in bus drivers. The conclusions drove the design of simulated scenarios to be used for bus driver training. Keywords: Bus, Simulator, Fidelity, Validity, Accidents, Driving, Stress, Training
159

Haptic Feedback

Pettersson, Oskar, Svensson, Erik January 2008 (has links)
Today, the use of simulators is very common and is used in many different areas, for example research, development and education. This trend has progressed due to simulators provide a cost efficient and safe platform for a large set of applications.  The assignment was given by the Division of Industrial Ergonomics and was titled “Haptic Feedback”. The purpose of this master thesis was how to add more realism into a fixed base car simulator by stimulating the human haptic perception.  When performing tasks in a substitute environment, the achieved data can differ in validity dependent on how “true” a simulator is. Therefore it is very important to resemble the actual environment as much as possible if one want data consistent with the real world. With the use of devices such as electrical motor and frequency converter, vibrations are created to simulate the vehicles contact with the surface of the road. The goal is not to recreate the real world physics – the goal is to add more realism in analogue with the present visual and audio setup.  To solve this problem many different subject areas are involved. Knowledge about software development, mechanics, construction, electronics and ergonomics are areas that are concerned in this master thesis.  Although this report will give a good overview of the haptic feedback concept, it is recommended that you visit the Virtual Reality-laboratory at the University of Linköping and try this application hands on in the simulator environment.
160

Simulator Oriented Control of Power in Bluetooth Wireless Sensor Networks

García, Manuel, Chicharro, Francisco Javier January 2009 (has links)
Create our own simulator much more oriented to Bluetooth networks, we will program the simulator in Java language and a graphical environment through Java. Fully modular and open so it can be expanded with more tools that we could develop. Initially the simulator will not work with all the specifications of Bluetooth, we will focus on the Bluetooth 2.0+EDR version. It will be only a demo version with several features working properly.

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