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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.
411

Evaluating the Use Of A Virtual Reality Patient Simulator an An Educational Tool In An Audiological Setting

Sanderson, Elizabeth Anne January 2013 (has links)
There is currently an international shortage of Audiologists (McIntyre, 2010). Audiology is a professional degree undertaken at a postgraduate level at most universities around the world. Students have training in anatomy and physiology, hearing aids, cochlear implants, electrophysiology and acoustics; combined with a clinical component to the course. The clinical component is undertaken throughout the entirety of the course and involves a mixture of observation and supervised clinical practice in a variety of settings. Clinical training often begins with students crowded around a single piece of equipment, such as an audiometer for testing puretone-hearing thresholds or by pairing up and simulating a hearing loss. This process creates time and access constraints for students as it restricts their ability to practice performing audiometry, particularly if there is a shortage of equipment, and also limits their exposure to a wide variety of hearing loss pathologies. The potential for universities worldwide to use Virtual Reality and Computer Based Simulations to provide Audiology students with basic clinical skills without relying on extensive support from external clinics warrants further investigation. In particular, it needs to be determined whether Audiology students value these simulations as a useful supplement to their clinical training, and whether the use of these simulations translates into measurable improvements in student abilities in real clinical placements. A computer based training program for Audiology students developed at the Human Interface Technology Lab (HITLAB) New Zealand is evaluated in this study as an educational tool at the University of Canterbury, New Zealand. The present study aims to determine if a sample of twelve first year Audiology students felt their interactions with Virtual Patients improved their ability to interact with clients and perform masking which is often part of a basic audiometric assessment for a patient with hearing loss. The study measures the students’ competency in performing masking in puretone audiometry on the Virtual Patient and then on a patient in a real-world setting to see whether the Audiology Simulator training tool improved the student’s basic audiometry skills (a training effect) and whether these skills were maintained after a period of four weeks (a maintenance effect). Statistical analysis is applied to determine any training and maintenance effects. Students also gave subjective feedback on the usefulness of the simulator and suggestions for ways in which it could be improved. Results indicated that there was no statistically significant training effect between students that had used the Audiology Simulator and those that hadn’t. Once all students had used the Virtual Patient there was an overall maintenance effect present in that student’s scores stayed the same or improved even for those students who had not used the Virtual Patient for a period of time. Students overall reported that they found the Virtual Patient to be ‘Moderately Useful’ and had many recommendations for ways in which it could be improved to further assist their learning.The present study indicates that computer based simulation programs like the Virtual Patient are able to present and simulate realistic hearing losses to an acceptable level of complexity for students studying in the field of audiology and that the Audiology Simulator can be a useful and complementary training tool for components of audiological clinical competence, such as puretone audiometry and masking.
412

Evaluation of an advanced fault detection system using Koeberg nuclear power plant data / H.L. Pelo.

Pelo, Herbert Leburu January 2013 (has links)
The control and protection system of early nuclear power plants (Generation II) have been designed and built on the then reliable analog system. Technology has evolved in recent times and digital system has replaced most analog technology in most industries. Due to safety precautions and robust licensing requirements in the nuclear industry, the analog and digital system works concurrent to each other in most control and protection systems of nuclear power plants. Due to the ageing, regular maintenance and intermittent operation, the analog plant system often gives faulty signals. The objective of this thesis is to simulate a transient using a simulator to reduce the effects of system faults on the nuclear plant control and protection system, by detecting the faults early. The following steps will be performed: • validating the simulator measurements by simulating a normal operation, • detecting faults early on in the system These can be performed by resorting to a model that generates estimates of the correct sensors signal values based on actual readings and correlations among them. The next step can be performed by a fault detection module which determines early whether or not the plant systems are behaving normally and detects the fault. (Baraldi P. et al, 2010.) / Thesis (MSc (Engineering Sciences in Nuclear Engineering))--North-West University, Potchefstroom Campus, 2013.
413

Evaluation of an advanced fault detection system using Koeberg nuclear power plant data / H.L. Pelo.

Pelo, Herbert Leburu January 2013 (has links)
The control and protection system of early nuclear power plants (Generation II) have been designed and built on the then reliable analog system. Technology has evolved in recent times and digital system has replaced most analog technology in most industries. Due to safety precautions and robust licensing requirements in the nuclear industry, the analog and digital system works concurrent to each other in most control and protection systems of nuclear power plants. Due to the ageing, regular maintenance and intermittent operation, the analog plant system often gives faulty signals. The objective of this thesis is to simulate a transient using a simulator to reduce the effects of system faults on the nuclear plant control and protection system, by detecting the faults early. The following steps will be performed: • validating the simulator measurements by simulating a normal operation, • detecting faults early on in the system These can be performed by resorting to a model that generates estimates of the correct sensors signal values based on actual readings and correlations among them. The next step can be performed by a fault detection module which determines early whether or not the plant systems are behaving normally and detects the fault. (Baraldi P. et al, 2010.) / Thesis (MSc (Engineering Sciences in Nuclear Engineering))--North-West University, Potchefstroom Campus, 2013.
414

Simulation of Surrounding Vehicles in Driving Simulators

Olstam, Johan January 2009 (has links)
Driving simulators and microscopic traffic simulation are important tools for making evaluations of driving and traffic. A driving simulator is de-signed to imitate real driving and is used to conduct experiments on driver behavior. Traffic simulation is commonly used to evaluate the quality of service of different infrastructure designs. This thesis considers a different application of traffic simulation, namely the simulation of surrounding vehicles in driving simulators. The surrounding traffic is one of several factors that influence a driver's mental load and ability to drive a vehicle. The representation of the surrounding vehicles in a driving simulator plays an important role in the striving to create an illusion of real driving. If the illusion of real driving is not good enough, there is an risk that drivers will behave differently than in real world driving, implying that the results and conclusions reached from simulations may not be transferable to real driving. This thesis has two main objectives. The first objective is to develop a model for generating and simulating autonomous surrounding vehicles in a driving simulator. The approach used by the model developed is to only simulate the closest area of the driving simulator vehicle. This area is divided into one inner region and two outer regions. Vehicles in the inner region are simulated according to a microscopic model which includes sub-models for driving behavior, while vehicles in the outer regions are updated according to a less time-consuming mesoscopic model. The second objective is to develop an algorithm for combining autonomous vehicles and controlled events. Driving simulators are often used to study situations that rarely occur in the real traffic system. In order to create the same situations for each subject, the behavior of the surrounding vehicles has traditionally been strictly controlled. This often leads to less realistic surrounding traffic. The algorithm developed makes it possible to use autonomous traffic between the predefined controlled situations, and thereby get both realistic traffc and controlled events. The model and the algorithm developed have been implemented and tested in the VTI driving simulator with promising results.
415

A model for simulation and generation of surrounding vehicles in driving simulators

Olstam, Johan January 2005 (has links)
Driving simulators are used to conduct experiments on for example driver behavior, road design, and vehicle characteristics. The results of the experiments often depend on the traffic conditions. One example is the evaluation of cellular phones and how they affect driving behavior. It is clear that the ability to use phones when driving depends on traffic intensity and composition, and that realistic experiments in driving simulators therefore has to include surrounding traffic. This thesis describes a model that generates and simulates surrounding vehicles for a driving simulator. The proposed model generates a traffic stream, corresponding to a given target flow and simulates realistic interactions between vehicles. The model is built on established techniques for time-driven microscopic simulation of traffic and uses an approach of only simulating the closest neighborhood of the driving simulator vehicle. In our model this closest neighborhood is divided into one inner region and two outer regions. Vehicles in the inner region are simulated according to advanced behavioral models while vehicles in the outer regions are updated according to a less time-consuming model. The presented work includes a new framework for generating and simulating vehicles within a moving area. It also includes the development of enhanced models for car-following and overtaking and a simple mesoscopic traffic model. The developed model has been integrated and tested within the VTI Driving simulator III. A driving simulator experiment has been performed in order to check if the participants observe the behavior of the simulated vehicles as realistic or not. The results were promising but they also indicated that enhancements could be made. The model has also been validated on the number of vehicles that catches up with the driving simulator vehicle and vice versa. The agreement is good for active and passive catch-ups on rural roads and for passive catch-ups on freeways, but less good for active catch-ups on freeways.
416

Assessment of Marine Conditions for Logistics, Operation Envelope and Weather Window for Offshore Projects

Rajesh, Edwin January 2011 (has links)
This thesis describes an assessment of offshore wind farms using a Matlab tool Marine System simulator. This tool helps to analyse the Vessel motion according to different wave heights. From this assessment one can know the correct weather window for offshore operation and other possible techniques to reduce the time delay in operation. This tool is used to simulate a supply vessel motion according to different wave heights. The chosen supply vessel is the default supply vessel in the simulator.
417

Design and Development of an Intelligent Energy Controller for Home Energy Saving in Heating/Cooling System

Abaalkhail, Rana 18 January 2012 (has links)
Energy is consumed every day at home as we perform simple tasks, such as watching television, washing dishes and heating/cooling home spaces during season of extreme weather conditions, using appliances, or turning on lights. Most often, the energy resources used in residential systems are obtained from natural gas, coal and oil. Moreover, climate change has increased awareness of a need for expendable, energy resources. As a result, carbon dioxide emissions are increasing and creating a negative effect on our environment and on our health. In fact, growing energy demands and limited natural resource might have negative impacts on our future. Therefore, saving energy is becoming an important issue in our society and it is receiving more attention from the research community. This thesis introduces a intelligent energy controller algorithm based on software agent approach that reduce the energy consumption at home for both heating and cooling spaces by considering the user’s occupancy, outdoor temperature and user’s preferences as input to the system. Thus the proposed approach takes into consideration the occupant’s preferred temperature, the occupied and unoccupied spaces, as well as the time spent in each area of the home. A Java based simulator has been implemented to simulate the algorithm for saving energy in heating and cooling systems. The results from the simulator are compared to the results of using HOT2000, which is Canada’s leading residential energy analysis and rating software developed by CanmetENERGY’s Housing, Buildings, Communities and Simulation (HBCS) group. We have calculated how much energy a home modelled will use under emulated conditions. The results showed that the implementation of the proposed energy controller algorithm can save up to 50% in energy consumption in homes dedicated to heating and cooling systems compared to the results obtained by using HOT2000.
418

Extending the Petrel Model Builder for Educational and Research Purposes

Nwosa, Obiajulu C 03 October 2013 (has links)
Reservoir Simulation is a very powerful tool used in the Oil and Gas industry to perform and provide various functions including but not limited to predicting reservoir performance, conduct sensitivity analysis to quantify uncertainty, production optimization and overall reservoir management. Compared to explored reservoirs in the past, current day reservoirs are more complex in extent and structure. As a result, reservoir simulators and algorithms used to represent dynamic systems of flow in porous media have invariably got just as complex. In order to provide the best solutions for analyzing reservoir performance, there is a need to continuously develop reservoir simulators and reservoir simulation algorithms that best represent the performance of the reservoir without compromising efficiency and accuracy. There exists several commercial reservoir simulation packages in the market that have been proven to be extremely resourceful with functionality that covers a wide range of interests in reservoir simulation yet there is the constant need to provide better and more efficient methods and algorithms to study and manage our reservoirs. This thesis aims at bridging the gap in the framework for developing these algorithms. To this end, this project has both an educational and research component. Educational because it leads to a strong understanding of the topic of reservoir simulation for students which can be daunting especially for those who require a more direct experience to fully comprehend the subject matter. It is research focused because it will serve as the foundation for developing a framework for integrating custom built external simulators and algorithms with the workflow of the model builder of our reservoir simulation package of choice i.e. Petrel with the Ocean programming environment in a seamless manner for simulating large scale multi-physics problems of flow in highly heterogeneous flow of porous media. Of particular interest are the areas of model order reduction and production optimization. In-house algorithms are being developed for these areas of interest and with the completion of this project. We hope to have developed a framework whereby we can take our algorithms specifically developed for areas of interest and add them to the workflow of the Petrel Model Builder. Currently, we have taken one of our in-house simulators i.e. a two dimensional, oil-water five-spot water flood pattern as a starting point and have been able to integrate it successfully into the “Define Simulation Case” process of Petrel as an additional choice for simulation by an end user. In the future, we will expand this simulator with updates to improve its performance, efficiency and extend its capabilities to incorporate areas of research interest.
419

A Simulation Tool For Mc6811

(tuncer) Sarikan, Nazli 01 December 2004 (has links) (PDF)
The aim of this thesis study is to develop a simulator for an 8-bit microcontroller and the written document of this thesis study analyses the process of devoloping a software for simulating an 8 bit microcontroller, MC68HC11. In this simulator study a file processing including the parsing of the assembler code and the compilation of the parsed instructions is studied. Also all the instruction execution process containing the cycle and instruction execution and the interrupt routine execution is observed through a graphical user interface. Through this graphical user interface all the registries, address bus and data bus updates can also be observed. C++ programming language is used to implement the application. Object oriented programing techniques are used to provide easy of implementation and template usages.
420

Simulation Of Depleted Gas Reservoir For Underground Gas Storage

Ozturk, Bulent 01 December 2004 (has links) (PDF)
For a natural gas importing country, &ldquo / take or pay&rdquo / approach creates problems since the demand for natural gas varies during the year and the excess amount of natural gas should be stored. In this study, an underground gas storage project is evaluated in a depleted gas Field M. After gathering all necessary reservoir, fluid, production and pressure data, the data were adapted to computer language, which was used in a commercial simulator software (IMEX) that is the CMG&rsquo / s (Computer Modelling Group) new generation adoptive simulator, to reach the history matching. The history matching which consists of the 4 year of production of the gas reservoir is the first step of this study. The simulation program was able to accomplish a good history match with the given parameters of the reservoir. Using the history match as a base, five different scenarios were created and forecast the injection and withdrawal performance of the reservoir. These scenarios includes 5 newly drilled horizontal wells which were used in combinations with the existing wells. With a predetermined injection rate of 13 MMcf/D was set for all the wells and among the 5 scenarios, 5 horizontal &ndash / 6 vertical injectors &amp / 5 horizontal - 6 vertical producers is the most successful in handling the gas inventory and the time it takes for a gas injection and production period. After the determination of the well configuration, the optimum injection rate for the entire field was obtained and found to be 130 MMcf/D by running different injection rates for all wells and then for only horizontal wells different injection rates were applied with a constant injection rate of 130 MMcf/d for vertical wells. Then it has been found that it is better to apply the 5th scenario which includes 5 horizontal &ndash / 6 vertical injectors &amp / 5 horizontal - 6 vertical producers having an injection rate of 130 MMcf/d for horizontal and vertical wells. Since within the 5th scenario, changing the injection rate to 1.3 Bcf/d and 13 Bcf/d, did not effect and change the average reservoir pressure significantly, it is best to carry out the project with the optimum injection rate which is 130 MMcf/d. The total gas produced untill 2012 is 394 BCF and the gas injected is 340 BCF where the maximum average reservoir pressure was recovered and set into a new value of 1881 psi by injection and cushion gas pressure as 1371 psi by withdrawal. If 5th scenario is compared with the others, there is an increase in injection and production performance about 90%.

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