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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.
201

The Effects of Windshield and Car Body on the Hidden Automotive Antenna

Tang, Tzu-chun 15 July 2009 (has links)
In this thesis, we discuss the subject into four parts. Firstly, we introduce the telematics for automotive. Secondary, we study the effects of locations of the hidden antenna. Thirdly, we discuss the effects of the windshield to the hidden antenna as we place the antenna on the windshield, then, the window film is attached to the windshield. We conduct implementation and measurement to analyze the effect of the film to the antenna. Finally, we find that the antenna gain is degraded in certain receiving angle due to the car body as we place the antenna at the corner of the windshield. In order to improve this, we design an EBG structure and place it between the antenna and the car body. The simulation result indicates that the EBG structure not only improves the gain in certain receiving angles but also reduces the induced current intensity on the car body.
202

A priori planning and real-time resources allocation /

Yang, Jian, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 96-108). Available also in a digital version from Dissertation Abstracts.
203

Tokamak resistive wall model validation and robust stabilization strategies.

Yang, Shuowei. Schuster, Eugenio, January 2009 (has links)
Thesis (M.S.)--Lehigh University, 2009. / Adviser: Eugenio Schuster.
204

Measuring China’s success in developing a framework for domestic innovation

Schultz, Kaye Frances 24 February 2015 (has links)
This report attempts to assess the degree to which China is developing a framework that supports domestic innovative capacity. This framework is not a predefined set of components, but is instead a combination of political, institutional, market, and technology factors and linkages that support information flows, interactions between entities, and incentives necessary to increase domestic innovation. Literature suggests that factors contributing to this framework may be influenced by domestic policy, and this report attempts to identify Chinese policies that contribute to the development of this framework within the Chinese solar photovoltaic (PV) and automotive industries. This report uses patent and export data as proxies for innovation in these two industries to measure the presence of this framework. The data suggest that the framework supporting domestic innovation in China is further developed for the solar PV industry than the automotive industry, but that the solar PV industry is still far from leading global innovation. Finally, the report identifies potential factors that have contributed to the variations between these two industries, and challenges that both industries may face in the near future. / text
205

Factors and policies affecting demand for light vehicle transportation in the lower mainland of British Columbia

Soucie, Michelle Anne 11 1900 (has links)
As transportation is a key component of economic success, it is crucial that the transportation systems in the Lower Mainland accommodate, and shape the projected increases in population. This paper has two main objectives. The first is to explore the factors and variables influencing demand for automobile transportation that are unique to the Lower Mainland of BC. General trends and statistics are explored for peak a.m. period automobile demand. The second part of this paper looks at the policies affecting demand for automobile transportation. Economic theory is introduced to two prominent traffic demand management (TDM) policies: road pricing and high occupancy vehicle (HOV) lanes. Conceptual models are proposed for both policies. In 1993 the GVRD completed the Transport 2021 study. Using data that was generated by the EMME2 model, empirical estimates of consumer surplus changes (resulting from various T DM policies being implemented) are considered under a range of elasticities. Empirical estimates of consumer surplus changes are also calculated for the conceptual models.
206

Transportation relay network design

Hunt, Gregory William 08 1900 (has links)
No description available.
207

Non-contact Measurement of Dynamic Belt Span Tension in Automotive FEAD Systems

Neudorf, Thelma Katherine 05 December 2013 (has links)
The proposed tension measurement method focuses on measurement of tension in a single belt span of the multi-pulley Front End Accessory Drive (FEAD) system. The mean belt span tension is calculated from the measured belt span natural vibration frequency. The oscillation belt span tension is calculated from the measured belt span transverse displacement. The dynamic belt span tension is calculated using the mean and oscillation tensions, belt span support pulley rotations, and belt slip, where the slip equation is based on Euler's equation. The proposed tension measurement method is validated using an experimental testing FEAD system which consists of a five pulley system and an automatic tensioner arm. Non-contact sensors are used to prevent disruption of the typical system behaviour. Testing conditions simulate typical engine crankshaft rotation input. Results from experimental testing consistently produce results with percent error less than 10 % for mean and maximum belt span dynamic tension.
208

The reduction of nitric oxide by carbon monoxide over excessively-exchanged copper ZSM-5 zeolite

Gilchrist, Ian Thomas January 1994 (has links)
Nitric oxide (NO) is a major pollutant which is produced by the combustion of fossil fuels. Current three-way catalyst (TWC) technology, used for the reduction of NO in automobile exhaust, is effective only under stoichiometric or net reducing conditions which cause incomplete use of the fuel and CO and hydrocarbon pollution. Excessively-exchanged Cu-ZSM-5 zeolite was investigated as a catalyst for the reduction of NO in net oxidizing exhaust mixtures, which would allow for greater fuel efficiency and lower NO, CO and hydrocarbon emissions. / Cu-ZSM-5 powder was pelletized by extrusion and the activity for the reduction of NO by CO on the presence of O$ sb2$ was measured at temperatures of 200$ sp circ$C to 550$ sp circ$C and a space velocity of 450 hour$ sp{-1}.$ The activity of the Cu-ZSM-5 was compared to that of a TWC at 550$ sp circ$C. Under stoichiometric or net reducing conditions the conversion to N$ sb2$ over both catalysts was about 100%. Under net oxidizing conditions (when the equivalence ratio, $ lambda$, is greater than 1) the conversion decreased with increasing oxygen concentration for both catalysts, but the Cu-ZSM-5 was much more active; at $ lambda=1.3$ the conversion was 53% compared to 26%. The Cu-ZSM-5 was found to deactivate after 30 hours of use. The deactivation was accompanied by a change in the Cu-ZSM-5 structure, and a change in the chemical composition. The deactivation was not found to be a function of the composition, or of the oxidative nature of the conditioning gas used (20% O$ sb2,$ inert, or 20% CO). Regeneration of the Cu-ZSM-5 proved unsuccessful.
209

The efficiency of mass transit operations in the transportation of people and in the utilization of city streets

Parrish, Emory Conrad 08 1900 (has links)
No description available.
210

Prognostic Health Assessment of an Automotive Proton Exchange Membrane Fuel Cell System

Rukas, Christopher J. 24 April 2015 (has links)
<p> Proton exchange membrane fuel cells are a promising technology for the automotive industry. However, it is necessary to develop effective diagnostic tools to improve system reliability and operational life to be competitive in the automotive market. Early detection and diagnosis of fuel cell faults may lead to increased system reliability and performance. An efficient on-line diagnosis system may prevent irreparable damage due to poor control and system fatigue. Current attempts to monitor fuel cell stack health are limited to specialized tests that require numerous parameters. An increased effort exists to minimize parameter input and maximize diagnostic robustness. Most methods use complex models or black-box methods to determine a singular fault mode. Limited research exists with pre-processing or statistical methods. This research examines the effectiveness of a Na&iuml;ve Bayes classifier on determining multiple states of health; such as healthy, dry, degraded catalyst, and inert gas build-up. Independent component analysis and principal component analysis are investigated for preprocessing. An automotive style fuel cell model is developed to generate data for these purposes. Since automotive applications have limited computational power, a system that minimizes the number of inputs and computational complexity is preferred.</p>

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