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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.
341

A Thermodynamics Based Model for Predicting Piston Engine Performance for Use in Aviation Vehicle Design

Highley, Justin L. 02 April 2004 (has links)
Advances in piston engine technology, coupled with high costs of turbine engines have led many general aviation manufacturers to explore the use of piston engines in their smaller vehicles. However, very few engine models are available to analyze piston engine performance. Consequently, designers using vehicle synthesis programs are unable to accurately predict vehicle performance when piston engines are used. This thesis documents the development of a comprehensive, thermodynamics based performance model that meets that need. The first part of this thesis details the basics of piston engine operation, including component geometry and the four stroke engine cycle. Next, the author analyzes the critical components of engine performance, including engine work and power. In developing the engine performance model the Ideal Engine Cycles are discussed. The cold air and fuel-air working fluid models are discussed, along with the types of combustion models, including the Otto Cycle, Diesel Cycle, and the Dual Cycle. Two performance models are generated using the Constant Volume Ideal Engine Cycle: an Ideal Gas Standard Cycle, and a Fuel-Air Cycle. The Ideal Gas Standard Cycle is useful for parametric analysis but lacks the accuracy required for performance calculations. The Fuel-Air Cycle, however, more accurately models the engine cycle and is selected as the basis for the computer program. In developing the computer program the thermodynamic charts used in the Fuel-Air Cycle calculations must be reproduced. To accomplish this, the NASA Chemical Equilibrium Application (CEA) program is integrated into a parent VBA based computer code to provide thermodynamic state point data. Finally, the computer program is correlated to the performance of an existing aviation engine to validate the model.
342

Innovative Design of the Control System for Remote Control Vehicles

Lin, Chung-le 05 February 2010 (has links)
Remote-controlled-vehicle Control System is a control system applied between the controller and remote-controlled-vehicle. For casual life is prevailing over recent years, old control systems should be replaced. The goal of this study is introducing a set of design methodology to design Remote-controlled-vehicle Control Systems by applying engineering design methods. At the first, we explored in the Remote-controlled-vehicle Control Systems. In order to clarify the design task, ¡§Objectives Tree¡¨ was applied to clarify six design tasks of need, and to establish the charts of seven design specification of Remote-controlled-vehicle Control Systems. In the concept design stage, we used the ¡§Function Analysis Method¡¨ to analysis and synthesis the function structure of the Remote-controlled-vehicle Control Systems, and we created two types of function structure, and found many working solutions of our concept by applying Creative Techniques. In the following embodiment design stage, we used ¡§Morphological Chart Method¡¨ to find 90 working solutions for type I, 90 solutions for type II, and finally evaluated and selected better ones by processing of ¡§Evaluation Chart¡¨ thrice. We evaluated the solutions of type I and type II, thus we got 22 solutions for each type, and in following, we evaluated all ones totally, got nine solutions in the second time, and got seven better and potential concepts of design in the third time, and drew the diagrams of real object. The result of this study can benefit the creative design and development of Remote-controlled-vehicle Control Systems.
343

X-by-wireless: a novel approach to vehicle control

Hoelscher, David Louis 15 May 2009 (has links)
As the cost of wireless devices approaches zero, it becomes more feasible to replace wires with wireless communication. Vehicle wiring harnesses are traditionally wired to communicate both power and information simultaneously, resulting in separate circuits for each vehicle device. X-By-Wireless seeks to supplant this configuration in favor of a shared power bus and wireless inter-component communication. In doing so, we can recognize a number of benefits such as reduced weight and increased reliability, flexibility, and upgradeability. However, this introduces new problems such as longer transmission delays, interference and encryption issues, fusing difficulties, and public perception regarding safety. The purpose of this thesis is to define the X-By-Wireless concept and to investigate the benefits and drawbacks in implementing X-By-Wireless. Furthermore, we do a theoretical and case study analysis to expand upon the weight reduction benefit so as to quantify the expected improvements. We also address each of the challenges presented by X-By-Wireless and integrate them into a proposed circuit that is capable of performing all the necessary functions of wireless control, wireless sensing, and fusing. We find that the proposed device can be mass-produced as an effective solution that meets the speed and security constraints necessary for most vehicle components.
344

Hybrid approaches to solve dynamic fleet management problems

Kim, Yŏng-jin, January 2003 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.
345

The potential of intelligent transport system (ITS) development in road transport of Hong Kong /

Cheung, Suk-ling. January 2001 (has links)
Thesis (M.A.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 138-141).
346

Improving ITS planning with multicriteria decision analysis

Wang, Zhong 28 August 2008 (has links)
Not available / text
347

The liability for damage caused by space activities /

Saleh, Saleh Tewfik. January 1967 (has links)
No description available.
348

A Study on the Charging of Electric Vehicles On a Prototypical Residential Feeder

Taylor, David 31 January 2014 (has links)
Due to recent concerns regarding energy conservation and dependence on fossil fuels, the efficient integration of electric vehicle populations’ in the future smart grid has become a significant area of research. Despite the heavy penetration of smart meters throughout North America and Europe a lack of research exists utilizing real consumption data. Making use of smart meter data, a model of a prototypical residential feeder was created to observe the effects of increased electric vehicle penetration on the selected feeder. Simulations of the current operation of the feeder were performed along with modeled uncoordinated, coordinated, and coordinated vehicle to grid charging of electric vehicles. As expected, it was found that the normal operation of the feeder is subject to several inefficiencies which are made worse by uncoordinated charging of electric vehicles. Significant improvements in the considered operational parameters were found as a result of the coordinated charging of vehicles using a quadratic programming based control algorithm. Further it was found, that the use of coordinated vehicle to grid connections only produces marginal benefits over standard connections. Leading to the conclusion that development of charging controls is more significant to the mitigation of electric vehicle charging effects than the integration of vehicle to grid connections. / Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2014-01-31 16:02:37.201
349

CAN Control System for an Electric Vehicle

Azzeh, Abdel Rahman January 2007 (has links)
The University of Canterbury has purchased a 1992 Toyota MR2 and used it as the platform to construct a new electric car. Similar to the common combustion engine vehicle, electric vehicles require control systems to control the operation of 12Vdc auxiliary loads, such as lights, indicators and windscreen wipers, where traditional technology results in a large number of wires in the wiring harness. Also, with the added complexity of modern vehicles, the need for integrating independent control systems together has become very important in providing safer and more efficient vehicles. To reduce the number of wires and make it possible for different control systems to communicate, and so perform more complex tasks, a flexible and reliable control system is used. The CAN (Controller Area Network) control system is a simple two-wire differential serial bus system, which was developed by Bosch for automotive applications in the early 1980s. The power and control system within the vehicle is named the "Power Distribution Network" and it is implemented by using multiple power converters and the CAN control system. This thesis presents the design, implementation, and test results of the CAN control system for the MR2. The 312Vdc nominal battery voltage is converted to an intermediate voltage of 48Vdc. This configuration is considered more efficient than the usual 12Vdc distribution system since smaller and lighter wires can be used to carry the same amount of power. The power distribution network operates off the 48Vdc intermediate voltage, and provides 12Vdc output to power all auxiliaries within the vehicle. The Power Distribution Network is implemented with two major subsystems: the auxiliary power system, which consists of multiple converters to step-down voltage from the 48Vdc intermediate voltage to the 12Vdc, and the CAN control system, which is developed to control and integrate the 12Vdc auxiliary loads within the vehicle. The prototype CAN control system is fully operational and has been tested with 12Vdc loads which are used to simulate most of the auxiliary loads in the vehicle. Experimental measurements show that the prototype is able to successfully control and maintain the network of independent nodes. This confirms that in principle the CAN control system is suitable for controlling the auxiliary loads in an electric vehicle.
350

An investigation of the dynamic coupling between a manipulator and anunderwater vehicle

Dunnigan, Matthew W. January 1994 (has links)
No description available.

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