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Unified Large And Small Signal State-Space Based Modeling And Symbolic Simulation For Pwm Converters, Ehab Shoubaki Jan 2009

Unified Large And Small Signal State-Space Based Modeling And Symbolic Simulation For Pwm Converters, Ehab Shoubaki

Electronic Theses and Dissertations

In this Dissertation, which concentrates on discrete modeling for control purposes of DC/DC converters and simulation through symbolic techniques. A Unified Discrete State-Space Model for power converters in CCM is presented. Two main approaches to arriving at the discrete model are used. The first approach involves an impulse function approximation of the duty cycle modulation of the converter switches, and this approach results in a small signal discrete model. The Second approach is direct and does not involve any approximation of the modulation, this approach yields both a large signal nonlinear discrete model and a linear small signal model. Harmonic …


Safety And Operational Evaluation Of Dynamic Lane Merging In Work Zones, Rami Harb Jan 2009

Safety And Operational Evaluation Of Dynamic Lane Merging In Work Zones, Rami Harb

Electronic Theses and Dissertations

Traffic safety and mobility of roadway work zones have been considered to be one of the major concerns in highway traffic safety and operations in Florida. In intent to expose Florida's work zones crash characteristics, the Florida Traffic Crash Records Database for years 2002, 2003 and 2004 were explored. Statistical models were estimated and Florida's work zone crash traits for single vehicle crashes and two-vehicle crashes were drawn. For the single-vehicle crashes, trucks were found more likely to be involved in single vehicle crashes in freeway work zones compared to freeways without work zones. Straight level roadways are significantly affected …


Dod Acquisition Workforce Education: An Sba Education Case Study, Richard Davenport Jan 2009

Dod Acquisition Workforce Education: An Sba Education Case Study, Richard Davenport

Electronic Theses and Dissertations

A Department of Defense (DoD) M&S education task force is in the process of studying the Modeling and Simulation (M&S) education of the acquisition workforce. Historically, DoD acquisition workforce education is not referred to as education, but rather what the Defense Acquisition University (DAU) refers to as "practitioner training, career management, and services." The DAU is the organization primarily responsible for training the DoD acquisition corps in conjunction with service schools and strategic partners in the civilian sector. DAU programs primarily focus on program management, contracting, and management of logistics across the system life cycle. Further, the examples and cases …


Presence-Dependent Performance Differences Between Virtual Simulations And Miniature Worlds, Andre Huthmann Jan 2009

Presence-Dependent Performance Differences Between Virtual Simulations And Miniature Worlds, Andre Huthmann

Electronic Theses and Dissertations

The purpose of simulation is to avoid reality-based constraints by the implemen-tation of a synthetic model. Based on this advantage, interactive simulations have conquered all areas of applications from acquisition, and training, to research. Simulation results are transferred in many ways into reality and conclusions are drawn from the simulation to the application. Many anecdotal observations on human-in-the-loop simulations have shown a significant difference in actor behavior between simulations and reality-based applications. It seems that the factors that makes simulation so attractive, namely the absence of constraints and especially of imminent danger for persons and equipment, influence the behavior and …


The Calibration, Validation, And Comparison Of Vissim Simulations Using The Two-Fluid Model, Jeremy Crowe Jan 2009

The Calibration, Validation, And Comparison Of Vissim Simulations Using The Two-Fluid Model, Jeremy Crowe

Electronic Theses and Dissertations

The microscopic traffic simulation program VISSIM is a powerful tool that has been used by transportation engineers and urban planners around the world. A VISSIM simulation is meant to depict the performance of the physical road network through the use of modeling tools and behavioral parameters. The process which gets the model to the point of matching real world conditions is called calibration and requires a means of relating the real world to the simulated world. The topic of this thesis discusses a new means of calibration using the two-fluid model. The two-fluid model is a macroscopic modeling technique which …