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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.
221

An Analysis Of The Saftey Effects Of Crosswalks With In-pavement Warning Lights

Gadiel, George 01 January 2007 (has links) (PDF)
Pedestrian safety is among one of the largest concerns in the transportation profession. Many treatments have been developed and implemented to improve pedestrian safety. This current research focuses on the efficiency of in-pavement warning lights systems and involves multiple objectives. The primary objective is to evaluate the yielding rates and crosswalk usage of existing and proposed in-pavement lights systems with comparisons including before and after data through a case study approach. A secondary objective is to evaluate where drivers are looking when they approach in-pavement lights systems and develop a model to evaluate their behavior. The research described herein formulated these objectives into two research hypotheses and used statistical evaluation methodologies to provide quantitative and/or qualitative responses to the developed hypotheses. Data on pedestrian and driver behavior in the field, and the interaction between, them was collected using video camera technology in the Amherst, Massachusetts area. Data regarding drivers scan patterns during the approach to a crosswalk with in-pavement warning light system was collected using a driving simulator and an eye tracker. In total, 1,949 non-staged pedestrians and 606 staged pedestrians were observed crossing at the seven crosswalk locations in the field experiment and a total of 32 drivers participated in 576 crosswalk scenarios in the driving simulator evaluation. The field evaluation resulted in increased yielding rates and crosswalk usage after installation of in-pavement warning lights, while driving simulator evaluation resulted in drivers not becoming accustomed to scanning for lights instead of a pedestrian. Recommendations include installation of in-pavement warning lights at traditional, midblock crosswalks and continued exploration of all crosswalks in the driving simulator evaluation.
222

Route Choice Behavior in a Driving Simulator With Real-time Information

Tian, Hengliang 01 January 2010 (has links) (PDF)
This research studies travelers' route choice behavior in a driving simulator with real-time information en-route. We investigate whether travelers plan strategically for real-time information en-route or simply select a fixed path from origin to destination at the beginning of a trip, and whether network complexity and a parallel driving task affect subjects' strategic thinking ability. In this study, strategic thinking refers to a traveler's route choice decision taking into account future diversion possibilities downstream enabled by information at the diversion node. All of the subjects in this study participated in driving-simulator-based tests while half of the subjects participated in additional PC-based tests. Three types of maps were used. The first type required a one-time choice at the beginning of a trip to test the traveler's risk attitude. The other two types offered route choices both at the beginning of and during a trip to test the traveler's strategic thinking. The study shows that a significant portion of route choice decisions are strategic in a realistic driving simulator environment. Furthermore, different network complexities impose different cognitive demands on a subject and affect his/her strategic thinking ability. A subject tends to be more strategic in a simple network. Lastly, a parallel driving task does not significantly affect a subject's strategic thinking ability. This seemingly counterintuitive conclusion might be caused by the simplicity of the tested network.
223

LowPy: Simulation Platform for Machine Learning Algorithm Realization in Neuromorphic RRAM-Based Processors

Ford, Andrew J. 28 June 2021 (has links)
No description available.
224

Development of Boiling Water Reactor Nuclear Power Plant Simulator for Human Reliability Analysis Education and Research

Gupta, Atul 16 May 2013 (has links)
No description available.
225

Control of a Robotic Vehicle Using a Driving Simulator

Su, Jian 23 August 2022 (has links)
No description available.
226

Cell Phone Distraction Analysis Of Motor Response In A Simulated Driving Environment

Ravishankar, Anusha 01 January 2004 (has links)
Does the use of a cell phone while driving influence the driver's ability to execute a proper turn? Is there difference between genders pertaining to motor skill while driving in a simulated driving environment? To accomplish this task, three groups of ten participants (5 women and 5 men) each were tested using a scripted test scenario focusing on left and right turns. The participants were made to drive through a test scenario to get used to the driving simulator. The scenario for the experimental group was an inner-city training scenario with the presence of vehicular traffic and the main focus area was on six critical turns (3 left and 3 rights). The apparatus used for this study was the "Patrol Simulator" built by GE Driver Development. A 2 (Gender) x 3 (Cell phone condition) between subjects design was used to assess the differences in mean driving performance between gender (male and female) at 3 cell phone conditions (No Phone, Phone No Conversation, Phone with Conversation). The study verified that cellular phones would adversely affects a driver's ability to perform turns, and showed that gender plays a role in this effect. However, it did confirm that gender does not play any role in a person's overall ability to drive. The results indicated a significant main effect for Cell phone Condition for overall turns , F (2, 24) = 38.83, p > .0005, n[eta]² = .76. Results also indicated a significant interaction between Gender and Cell Phone Conditions, F (2, 24) = 3.97, p=.032, n[eta]² = 0.25.
227

Quality Of Service Measures At Signalized Intersections

Goyal, Kamal 01 January 2005 (has links)
The concept of using qualitative measures to describe the quality of service at signalized intersections provided by different designs and controls has been discussed in numerous conferences. Such measures may include driver's comfort, convenience, anxiety, and preferences. The primary objective of this study was to demonstrate the feasibility of using the University of Central Florida's interactive driving simulator to execute several scenarios involving different unusual design and operation practices to measure the quality of service at a signalized intersection. This thesis describes the scenarios, the experiments conducted, the data collected, and analysis of results. Signalized intersections with 3 types of characteristic features were identified for this study. They included 1. A lane dropping on the downstream side of the intersection 2. Misalignment of traffic lanes between the approach and downstream side 3. Shared left turn and through traffic lane or separate lanes for each approaching the intersection The experimental phase consisted of a brief orientation session to get acclimated to the driving simulator followed by two driving scenarios presented to all subjects. Each scenario consisted of a drive through an urban section of the simulator's visual data base where each subject encountered a Type 1, 2 and 3 intersections. A total of 40 subjects, 25 males and 15 females were recruited for the experiment. Data logging at 60 Hz for each scenario consisted of time-stamped values of x-position and y-position of the simulator vehicle, steering, accelerator and brake inputs by the driver, and vehicle speed. After the experiment a questionnaire soliciting opinions and reactions about each intersection was administered. Simulator experiment results showed that there was a significant difference between the merge lengths for the two cases of Type 1 intersection (lane drop on the downstream side of the intersection). For Type 2 intersection (misalignment of traffic lanes between the approach and downstream side) there was a considerable difference between the average paths followed by subjects for the two cases. For Type 3 intersection (shared left and through traffic lane approaching the intersection) the simulator experiment supported the fact that people get frustrated when trapped behind a left turning vehicle in a joint left and through lane intersection and take evasive actions to cross the intersection as soon as possible.
228

An Authentic Ecg Simulator

Michalek, Paul 01 January 2006 (has links)
An ECG (electrocardiogram) simulator is an electronic tool that plays an essential role in the testing, design, and development of ECG monitors and other ECG equipment. Principally an ECG simulator provides ECG monitors with an electrical signal that emulates the human heart's electrical signal so that the monitor can be tested for reliability and important diagnostic capabilities. However, the current portable commercially available ECG simulators are lacking in their ability to fully test ECG monitors. Specifically, the portable simulators presently on the market do not produce authentic ECG signals but rather they endeavor to create the ECG signals mathematically. They even attempt to mathematically create arrhythmias (irregular heartbeats of which there are many different types). Arrhythmia detection is an important capability for any modern ECG monitor because arrhythmias are often the critical link to the diagnosis of heart conditions or cardiovascular disease. The focus of this thesis is the design and implementation of a portable ECG simulator. The important innovation of this prototype simulator is that it will not create its ECG signals mathematically, but rather it will store ECG data files on a memory module and use this data to produce an authentic ECG signal. The data files will consist of different types of ECG signals including different types of arrhythmias. The data files are obtained via the internet and require formatting and storing onto a memory chip. These files are then processed by a digital to analog converter and output on a four lead network to produce an authentic ECG signal. The system is built around the ultra-low power Texas Instruments MSP430 microcontroller.
229

Modification of the Cal Poly Spacecraft Simulator System for Robust Control Law Verification

Kato, Tomoyuki 01 June 2014 (has links) (PDF)
The Cal Poly Spacecraft Dynamics Simulator, also known as the Pyramidal Reaction Wheel Platform (PRWP), is an air-bearing four reaction wheel spacecraft simulator designed to simulate the low-gravity, frictionless condition of the space environment and to test and validate spacecraft attitude control hardware and control laws through real-time motion tests. The PRWP system was modified to the new Mk.III configuration, which adopted the MATLAB xPC kernel for better real-time hardware control. Also the Litton LN-200 IMU was integrated onto the PRWP and replaced the previous attitude sensor. Through the comparison of various control laws through motion tests the Mk.III configuration was tested for robust control law verification capability. Two fixed-gain controllers, full-state feedback (FSFB) and linear quadratic regulator with set-point control(LQRSP), and two adaptive controllers, nonlinear direct model reference adaptive controller (NDMRAC) and the adaptive output feedback (AOF), were each tested in three different cases of varying plant parameters to test controller robustness through real-time motion tests. The first two test cases simulate PRWP inertia tensor variations. The third test case simulates uncertainty of the reaction wheel dynamic by slowing down the response time for one of the four reaction wheels. The Mk.III motion tests were also compared with numerical simulations as well as the older Mk.II motion tests to confirm controller validation capability. The Mk.III test results confirmed certain patterns from the numerical simulations and the Mk.II test results. The test case in which actuator dynamics uncertainty was simulated had the most effect on controller performance, as all four control laws experienced an increase in steady-state error. The Mk.III test results also confirmed that the NDMRAC outperformed the fixed-gain controllers.
230

Investigations into self motion thresholds using a Stewart platform / Investigations into self motion thresholds using a Stewart platform

Akbari, Behzad 06 1900 (has links)
Full motion simulators are traditionally used in the flight industry to train pilots. They are used to add the sensation of acceleration in simulation to make it more "realistic". Clearly the motion envelop of the simulator is limited by physical constraints so the motion platform has to be stopped and returned to the center position after an acceleration cue, called washout. A key question is: which acceleration can a subject feel and which not, called the acceleration threshold. We are also interested in strength of accelerations for which a subject can detect the direction. Literature gives several results, but we found that some of these values seemed very low to us and the experiments were conducted on very specific groups of people like pilots, A.J.Benson and H.Vogel (1986), Schroeder (1999). Furthermore, we are simulating moving vehicles like a car or an air plane and are interested in the acceleration ranges in a noisy environment. Noisy, the noise is a result from the vibration of engines, rough roads and disturbances that are Gaussian. This thesis gives a literature review, implement the cueing procedure to make motion and vibration to do different experiment and analyze the results. / Thesis / Master of Computer Science (MCS)

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