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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.
181

Modifying Driver Following Behaviour with a Real-Time Headway Evaluation System

Ramkhalawansingh, Robert, Trick, Lana, Nonnecke, Blair 12 September 2012 (has links)
Tailgating (maintaining an inadequate headway) is a major road safety concern that emerges because drivers tend to misperceive their following distance. Drivers seldom receive enough feedback to correct this error, leaving them vulnerable to rear-end collisions. While there have been attempts to address this issue through vehicle automation and warning systems, these approaches have not been sensitive to the needs of young drivers. The present investigation sought to implement a headway evaluation system: an in-vehicle display designed to provide motorists with real-time as well as aggregate headway feedback. This system was designed to teach drivers to recognize safe headways and to motivate adherence. Compared to drivers selecting their own headway or those attempting to count a two second headway, drivers using the headway evaluation system maintained longer headways that would be conducive to collision avoidance. This system may be beneficial as a training device for new drivers. / AUTO21, the Ontario Innovation Trust, the Canada Foundation for Innovation, and the Natural Sciences and Engineering Research Council of Canada
182

Effect of interpersonal competition on the driving performance of young male drivers accompanied by young male passengers

Subasi, Ece 04 September 2013 (has links)
Motor vehicle accidents are the leading cause of death and injury among teenagers. The crash risk is highest for young male drivers with young male passengers. The goal of this study is to find out why young males are at such high risk. One possible explanation could be the Sexual Selection Theory (Darwin, 1871), which emphasizes the competitive nature of young males that may determine their behaviour for future benefits. I tested if there was competition between males that made them take more risks while driving in the simulator. Various driving performance variables (speed, car following distance, standard deviation of the lateral position, hazard response times, number of vehicles passed) and individual differences variables (risky driving, risk perception, sensation seeking, competitiveness) were measured. Results provided little support for the effect of interpersonal competition and an opportunity for discussion arose. / AUTO21, Ontario Innovation Trust (OIT), Canadian Foundation for Innovation (CFI).
183

An Augmented Reality Haptic Training Simulator for Spinal Needle Procedures

SUTHERLAND, COLIN JAMES 29 November 2011 (has links)
Medical simulators have become commonly used to teach new procedures to medical students and clinicians. Their accessibility allows trainees to perform training whenever they desire, and their flexibility allows for various patient body types and conditions to be simulated. This is in contrast to {\it in-vivo} training, which requires direct supervision from a trained clinician, and access to a live patient or cadaver, both of which have restrictions. This thesis proposes a novel prototype system for spinal anesthesia procedures which combines the use of both a haptic device for virtual, ultrasound-guided (US) needle simulations, and a physical mannequin registered to a patient specific computed tomography (CT) volume in order to create an augmented reality (AR) overlay. The mannequin will provide the user with a greater sense of spatial awareness that is not present in a purely virtual simulation, as well as providing physical visual clues to navigate the patient. Another novel aspect is the simulation of US images from CT images deformed via a finite element model (FEM). The system is composed of a torso mannequin from Sawbones Inc., a MicronTracker2 optical tracking system from Claron Technology, a Sensable PHANToM Premium 1.5A haptic device and a graphical user interface (GUI) to display relevant visual feedback. The GUI allows the user to view the AR overlaid on the video feed, and the CT slice and simulated US image based the position/orientation of a dummy US probe. Forces during the insertion are created via the FEM and sent to the haptic device. These forces include force from needle tip insertion, friction along the length of the needle inside the body, and from displacing the needle off its original insertion axis. Input to the system consists of a patient CT volume. The system is able to create forces that closely match those reported in the literature. A user study consisting of subjects with expertise ranging from familiarity with medical imaging to clinical experience with needle insertion procedures, was performed to qualitatively analyze the performance of the system. Three experienced physicians were also consulted for input and improvements. The feedback received from the questionnaire, and comments from the subjects and physicians, showed the system is able to simulate a real needle insertion quite well, and the graphical aids added were helpful during the training procedure. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2011-11-27 00:04:32.173
184

Formative feedback in a virtual patient simulator for clinical audiology training

Guard, Lynda May January 2013 (has links)
The aim of this study was to examine the effectiveness of different types of feedback on learning pure-tone audiometry using a simulator. Participants were 51 undergraduate students in the Department of Communication Disorders. Participants were randomly allocated to one of two groups whilst undertaking pure-tone audiometry training with the Clinical Audiology Simulator (CAS). One group received summative feedback during the learning task while the second group received formative feedback. Probes were administered to examine participants’ knowledge of pure-tone audiometry following training. In addition, a subjective workload analysis was used to measure perceived cognitive load during training and assessment. Between-groups analysis was conducted to establish the effect of feedback on learning and cognitive load. Data regarding how much time each student spent training on the simulator was also collected, and a regression analysis was conducted to evaluate the relationship between time and learning. Formative feedback was found to have a large positive effect on learning in comparison to summative feedback. Cognitive load was perceived as being higher for students receiving formative feedback during training compared to those receiving summative feedback. In subsequent assessment, the formative feedback group reported a lower cognitive load than the summative feedback group. No relationship was observed between time spent training on the simulator and probes outcome. The formative feedback training mode of the CAS proved to be effective in supporting learning and cognitive load in novice students. The findings suggest that the type of feedback employed when using simulators affects learning outcomes for users.
185

Traffic Simulation Modelling of Rural Roads and Driver Assistance Systems

Tapani, Andreas January 2008 (has links)
Microscopic traffic simulation has proven to be a useful tool for analysis of varioustraffic systems. This thesis consider microscopic traffic simulation of rural roads andthe use of traffic simulation for evaluation of driver assistance systems. A traffic simulation modelling framework for rural roads, the Rural Traffic Simulator(RuTSim), is developed. RuTSim is designed for simulation of traffic on singlecarriageway two-lane rural roads and on rural roads with separated oncoming trafficlanes. The simulated traffic may be interrupted by vehicles entering and leaving themodelled road at intersections or roundabouts. The RuTSim model is applied for analysis of rural road design alternatives.Quality-of-service effects of three alternatives for oncoming lane separation of anexisting Swedish two-lane road are analysed. In another model application, RuTSimis used to simulate traffic on a Dutch two-lane rural road. This application illustratesthat the high level of model detail of traffic micro-simulation may call for use of differentmodelling assumptions regarding driver behaviour for different applications,e. g. for simulation of traffic in different cultural regions. The use of traffic simulation for studies of driver assistance systems facilitateimpact analyses already at early stages of the system development. New and additionalrequirements are however then placed on the traffic simulation model. It isnecessary to model both the system functionality of the considered driver assistancesystem and the driver behaviour in system equipped vehicles. Such requirements canbe analysed using RuTSim. In this thesis, requirements on a traffic simulation model to be used for analysisof road safety effects of driver assistance systems are formulated and investigatedusing RuTSim. RuTSim is also applied for analyses of centre line rumble stripson two-lane roads, of an overtaking assistant and of adaptive cruise control. Thesestudies establish that the assumptions made regarding driver behaviour are crucialfor traffic simulation based analyses of driver assistance systems.
186

Mc6811 Microcontroller Simulation Toolkit

Taskin, Tolga 01 November 2005 (has links) (PDF)
The goal of this thesis study is to develop a simulator toolkit for Motorola&rsquo / s 8-bit microcontroller MC6811. The toolkit contains a cross-assembler to obtain object code from the source code and a simulator to run the object code. Written document of this thesis study describes the properties of the MC6811 microcontroller and its assembly language. In addition, the document describes the cross-assembler and simulator parts of the toolkit with details. In the cross-assembler part of the toolkit, parsing of the source Code and processing of the parsed information is studied. The simulator part studies the execution of the object code generated by the crossassembler. The execution of each instruction and main functions of the microcontroller can be observed from a Graphical User Interface (GUI). The Central Processing Unit (CPU), the busses, ports and interrupts of the microcontroller are included into the GUI. C++ programming language is used to develop and to implement the toolkit.
187

Obstructive sleep apnoea and driver performance: prevalence, correlates and implications for driver fatigue

Desai, Anup Vijayendra January 2003 (has links)
Obstructive sleep apnoea (OSA) is characterised by repetitive reductions or pauses in breathing during sleep due to upper airway narrowing or closure. Due to disruption to normal sleep patterns, many patients with OSA suffer from increased daytime sleepiness. Epidemiological studies have established a link between OSA and driver fatigue and accidents, generally showing a two to seven times increased risk of road traffic accidents in non-commercial drivers with OSA. There is emerging evidence that commercial drivers have a higher prevalence of OSA than the general population, being predominately male, middle-aged and overweight, three important risk factors for OSA. However, little is known about the relationship between OSA and driver sleepiness in commercial drivers, whether road accidents are increased in commercial drivers with OSA, and whether OSA interacts with other fatigue promoting factors, such as sleep deprivation, to further escalate road accident risk. One thousand randomly selected commercial drivers were surveyed in the field. In addition, 61 randomly selected NSW commercial drivers had in hospital sleep studies and daytime performance testing, including a PC based driving simulator task. The prevalence of OSA, defined as Respiratory Disturbance Index (RDI) < 10, was approximately 50% in NSW commercial drivers. Approximately one quarter of the drivers reported pathological daytime sleepiness, and 12-14% had both OSA and pathological daytime sleepiness. A diagnosis of OSA was the most important factor predicting excessive daytime sleepiness in these drivers: OSA was more important than 15 other work-related, lifestyle and medical factors that could be expected to promote, or be associated with, daytime sleepiness. Drivers with sleep apnoea syndrome (both OSA and pathological daytime sleepiness) had an increased driving accident risk, using driving simulator and daytime performance testing as proxy measures for accident risk. These results demonstrate the importance of OSA as a cause of driver fatigue in commercial drivers and suggest that all commercial drivers should be screened for the presence of sleep apnoea syndrome in order to potentially reduce road accident risk through treatment. A separate, but related body of work examined the combined effects of mild OSA and other fatigue promoting factors (sleep deprivation and circadian influences) on driving performance. Twenty nine subjects, consisting of a group with mild OSA and a group of non-OSA controls, were tested on several occasions throughout the night and day using an intensive performance battery, under both baseline conditions and after a period of 36 hours of total sleep deprivation. The results suggest that drivers with mild OSA are not different to the control group in their response to sleep deprivation or time of day influences. However, the subjects with mild OSA were less aware of their impairment due to sleep deprivation, which is of concern if drivers with OSA are relying on their subjective awareness of fatigue to make decisions about when to stop driving. A final perspective on OSA and driver fatigue is provided through a clinical case series of seven fall-asleep fatality associated MVA�s associated with unrecognised or under-treated sleep disorders. As well as demonstrating the day to day potential for devastating road accidents due, at least in part, to un-recognised or untreated sleep disorders, these cases also serve to highlight some of the current medico-legal controversies and difficulties in this area of driver fatigue. In conclusion, this body of work has provided novel information about the epidemiology and implications of OSA in commercial drivers, and about how OSA interacts with other fatigue promoting factors. Finally, it has explored some of the medico-legal issues that relate to sleep disorders and driver fatigue. As well as providing much needed information in the area of driver fatigue, at the same time this work raises many more questions and suggests areas of future research. For instance, such research should examine the relationship between objective accident rates and OSA/sleep apnoea syndrome in commercial drivers, the interaction between mild sleep apnoea syndrome and other fatigue risk factors, and driver perception of sleepiness prior to sleep onset in drivers with sleep disorders.
188

FDS modelling of hot smoke testing, cinema and airport concourse

Webb, Alex K. January 2006 (has links)
Thesis (M.S.) -- Worcester Polytechnic Institute. / Keywords: Hot smoke test; FDS; CFD; Computer modelling. Includes bibliographical references (p.105-110).
189

The adaptive effects of virtual interfaces : the vestibulo-ocular reflex and simulator sickness /

Draper, Mark, January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [268]-281).
190

Um simulador de redes de petri de alto nível para uso didático / A petri-net simulator for didactic use

Glock, Flavio Soibelmann January 1992 (has links)
O presente trabalho consiste na apresentação da implementação de um software projetado para auxiliar o ensino de redes de Petri de alto nível. A partir da fundamentação sobre o assunto desenvolvida em cursos introdut6rios de modelagem de sistemas com redes de Petri foi especificado um sistema para ser usado em sala de aula. O sistema desenvolvido permite a demonstração das características gráficas e da semântica de alguns modelos tradicionais de redes de Petri, tais como redes condicao/evento, redes predicado-transição e redes coloridas. Redes de baixo nivel tambem podem ser demonstradas. O software foi elaborado de forma a permitir a utilização de redes já definidas em disquete. O usuário pode também definir novas redes utilizando o editor gráfico/compilador ou se valer de uma linguagem textual de baixo nível para descrever as redes. Após a obtenção da rede desejada, é possível a realização de demonstrações, simulando o funcionamento da mesma. O software permite ainda a execução de passos, o funcionamento "para trás" da rede e identifica, a cada estado alcançado, quais alterações estão habilitadas e quais estão em conflito. Um comando permite obter o caminho entre duas marcações da rede. O usuário pode selecionar regiões de interesse sobre a rede, que sera° mostradas com mais detalhe na tela. Usando o editor gráfico/compilador o usuário pode modificar redes durante o decorrer da apresentação. A interface com o usuário, voltada para o use em sala de aula, necessita como hardware um projetor de vídeo apropriado e um computador pessoal equipado com mouse. A utilização do compilador em sala de aula exige, no entanto, mais recursos computacionais que o simulador. Alguns modelos de redes de Petri não são suportados pelo compilador, mas podem ser implementados utilizando a linguagem de baixo nível do sistema. 0 usuário, professor ou aluno, encontrará neste trabalho instruções para o emprego pratico do sistema como instrumento para a realização de demonstrações didáticas. / This work describes the implementation of a software designed as a teaching aid for instructors of high-level Petri nets. A system for class-room use is described that is based on material developed during introductory courses of systems modelling with Petri nets. The class-room system permits the demonstration of the graphic properties and the semantics of some traditional nets, such as condition/event nets, predicate-transition nets and coloured nets, as well as low level nets. The software was designed to permit the use of nets already defined in diskettes. The user can define new nets using either the graphic editor/compiler or a low level textual language. Some models of Petri nets are not supported by the compiler, but can be implemented using the low level language. After obtaining the desired net, it is possible to perform demonstrations, simulating its operation.The software also allows step by step execution of nets, including backwards execution, and identifies, for every state, which alterations may happen and which are in conflict. A command permits the user to obtain the path between two markings of the net. The user may select regions of interest over the net, that will be shown with more detail in the screen. Using the graphic editor/compiler the user may modify the nets during the presentation. The hardware needs are a video projector and a personal computer equiped with a mouse.

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