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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.
141

Effects of Cell Phone Notification Levels on Driver Performance

January 2019 (has links)
abstract: Previous literature was reviewed in an effort to further investigate the link between notification levels of a cell phone and their effects on driver distraction. Mind-wandering has been suggested as an explanation for distraction and has been previously operationalized with oculomotor movement. Mind-wandering’s definition is debated, but in this research it was defined as off task thoughts that occur due to the task not requiring full cognitive capacity. Drivers were asked to operate a driving simulator and follow audio turn by turn directions while experiencing each of three cell phone notification levels: Control (no texts), Airplane (texts with no notifications), and Ringer (audio notifications). Measures of Brake Reaction Time, Headway Variability, and Average Speed were used to operationalize driver distraction. Drivers experienced higher Brake Reaction Time and Headway Variability with a lower Average Speed in both experimental conditions when compared to the Control Condition. This is consistent with previous research in the field of implying a distracted state. Oculomotor movement was measured as the percent time the participant was looking at the road. There was no significant difference between the conditions in this measure. The results of this research indicate that not, while not interacting with a cell phone, no audio notification is required to induce a state of distraction. This phenomenon was unable to be linked to mind-wandering. / Dissertation/Thesis / Masters Thesis Human Systems Engineering 2019
142

Adaptação de veículos autónomos e inteligentes e análise de desempenho no Fligth Simulator X

Santos, Abel Fernando Neto Moreira dos January 2010 (has links)
Tese de mestrado integrado. Engenharia Informática e Computação. Faculdade de Engenharia. Universidade do Porto. 2010
143

A field- and laboratory-based investigation of shallow debris flow initiation on unburned slopes in southern California

Brady, Jordan E. 01 August 2019 (has links)
Debris flows are a known hazard in southern California where growing numbers of people are moving into the urban-wildland interface, threatening lives and property. A common location to see a debris flow head scarp is the upper one-third to one-half of an unburned slope at or near the head of a first-order catchment, particularly in areas of relatively shallow soils overlying bedrock. Unburned, relatively steep slopes with gently rounded shoulders and thin soil over bedrock in southern California were investigated to determine if there is a position on these types of slopes where near-surface water levels and the associated pore pressures are relatively and consistently higher during and after rainfall events than the rest of the slope, resulting in an area of preferential shallow slope failure and debris flow initiation. It was hypothesized that this position, if it exists, would be on the upper one-third to one-half of the slope near a change from a shallower slope to a steeper slope (the slope shoulder). It was further hypothesized that elevated subsurface pore pressures at this location would contribute to it being an area of preferential shallow slope failure. The near-surface water levels at two field sites in southern California were monitored for three field seasons. In the laboratory, a meso-scale simulator was constructed and used to replicate field conditions using an adjustable artificial slope and simulated rainfall. The field research showed that areas of higher water levels can exist on the upper one-third to one-half of hillslopes meeting the designated criteria. The laboratory simulations showed elevated water levels in the same general area as the field data. Laboratory simulations also suggested that this is an area of preferential shallow slope failure. The angle of the slope influenced how long a slope took to fail and how much water was needed to do so, with gentler slopes requiring more time and approximately double the amount of water than steeper slopes.
144

PIPPIN MACHINE

Pamulaparthy, Kiran Reddy 01 March 2017 (has links)
The PIPPIN machine describes two simulations which are intended to help students understand the compile and execute process of a simple computer. The first simulator takes a simple mathematical expression as input and then translates it into an assembly language. The second simulator will execute an assembly language program.
145

Advancements of a servohydraulic human hip joint motion simulator for experimental investigation of hip joint impingement/dislocation

Stroud, Nicholas James 01 July 2010 (has links)
A servohydraulic hip simulator was upgraded to experimentally investigate cadaveric impingement/dislocation of the hip with clinically releveant joint motions. The resulting biomechanical analysis provided insight into risk factors for dislocation/impingement and clearly demonstrated the potential of the hip simulator as a research tool.
146

Partial Evaluation Based Triple Modular Redundancy For Single Event Upset Mitigation

Kakarla, Sujana 24 March 2005 (has links)
We present a design technique, called partial evaluation triple modular redundancy for hardening combinational circuits against Single Event Upsets (SEU). The input environment is given in terms of signal probabilities of the lines. This is useful information to determine the redundant gates of the given circuit. The basic ideas of partial redundancy and temporal triple modular redundancy are used together to harden the circuit against SEUs. The concept of partial redundancy is used to eliminate the gates whose outputs can be determined in advance. This technique fails in cases when the actual inputs to the circuit are not in accordance to the rounded logic values. In such cases the technique of temporal TMR is used. However, there is some overhead in this process because of the voter circuits and the need to choose the outputs computed by partially evaluated circuit and circuit using temporal TMR. For testing the circuit exhaustively against SEUs, a fault insertion simulator is used. This simulator introduces errors in the circuits during simulation which represent SEUs. This technique of partial evaluation redundancy is thoroughly tested on MCNC’91 benchmarks using Cadence NCLaunch simulator. By employing this technique, in most of the cases we can reduce the area overhead of the hardened circuit when compared with the traditional Triple Modular Redundancy (TMR). The improvement in area is based on the total number of gates and the actual number of outputs. For circuits with large number of gates and less number of outputs, there is greater savings in area. In some cases, the area overhead because of the proposed technique is greater than the traditional TMR. This usually occurs in smaller circuits or in circuits with more number of outputs.
147

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.
148

Simulator Oriented Control of Power in Bluetooth Wireless Sensor Networks

García, Manuel, Chicharro, Francisco Javier January 2009 (has links)
<p>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.</p>
149

Simbase: ”Simulator Base Package” / Simbase: ”Simulator Base Package”

Rydén, Eva, Samuelsson, Ralf January 2002 (has links)
<p>The purpose of this work is to providing a general set of base classes for building simulators, for example a robot system. Instead of every time building a new simulator from the beginning, you get the already completed components from a library. The library should in that way act as a springboard for development.</p><p>To do this work, there’s a lot of knowledge required in how a general robot system could look like. Therefore it was necessary to gather some information about robotics. </p><p>On the basis of what the information gave, two different user cases were built. From these user cases, the components were fetched, which was supposed to be included in the library. </p><p>The result of this work leads to a number of classes, which describes the components. A simple test program is also done, which handles the components. To get the classes more useful, the com-ponents must be broken down in much smaller parts. The operations on the classes should also be more realistic than what has been achieved in this work.</p>
150

Haptic Feedback

Pettersson, Oskar, Svensson, Erik January 2008 (has links)
<p>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. </p><p>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. </p><p>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. </p><p>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. </p><p>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.</p>

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