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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.
61

A flexible power management system for interfacing with energy harvesting transducers

Guilar, Nathaniel J. January 1900 (has links) (PDF)
Thesis (Ph.D.)--University of California, Davis, 2008. / Adviser: Rajeevan Amirtharajah. Includes bibliographical references.
62

Self powered sensing by combining novel sensor architectures with energy harvesting

Bedekar, Vishwas. January 2009 (has links)
Thesis (Ph.D.)--University of Texas at Arlington, 2009.
63

Searching for the biofuel energy crisis in rural Java

McGranahan, Gordon. January 1986 (has links)
Thesis (Ph. D.)--University of Wisconsin-Madison, 1986. / Cover title. Includes bibliographical references (p. 362-387).
64

Nanogenerators

Song, Jinhui. January 2008 (has links)
Thesis (Ph.D.)--Materials Science and Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Zhong lin Wang; Committee Member: Christopher J. Summers; Committee Member: Kenneth A. Gall; Committee Member: Robert L. Snyder; Committee Member: Russell D. Dupuis.
65

Ending America's dependence on foreign oil : risk perceptions among Texans /

Aldridge, Jessica R. January 2009 (has links)
Thesis (M.A.)--Western Kentucky University, 2009. / Includes bibliographical references (leaves 57-63).
66

China's allocation of authority and responsibility in energy production and distribution changing center-periphery relations /

Chan, Man-jung Mignon. January 1988 (has links)
Thesis (Ph. D.)--Boston University, 1986. / Includes bibliographical references (p. 281-304).
67

Community educational processes group perceptions of energy issues /

Blalock, Carol Douglass, January 1980 (has links)
Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 132-135).
68

Vibration energy scavenging and management for ultra low power applications /

Lu, Chao. January 2007 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 68-71). Also available in electronic version.
69

Estratégias do Movimento Estudantil nas Políticas Públicas de Transporte na Região Metropolitana da Grande Vitória.

SILVA, W. V. 21 December 2017 (has links)
Made available in DSpace on 2018-08-01T23:38:08Z (GMT). No. of bitstreams: 1 tese_11633_Versão Final Dissertação de Mestrado 12 abril 2018.pdf: 1624535 bytes, checksum: 253598453ceda468bebfb369f560e72b (MD5) Previous issue date: 2017-12-21 / O Movimento Estudantil (ME) é um ator social de grande importância no debate de políticas públicas de transporte. Com esta visão, este trabalho é resultado de uma pesquisa qualitativa que teve por objetivo compreender os movimentos orgânicos e reivindicatórios dos estudantes enquanto atores sociais no processo de formação de políticas públicas de transporte na Região Metropolitana da Grande Vitória (RMGV), por meio da utilização de estratégias políticas. Para embasar teoricamente esta pesquisa são apresentados conceitos sobre formação de políticas públicas, participação social, recursos de poder e estratégias políticas. De maneira a compreender a evolução das bandeiras do ME e identificar suas estratégias políticas, procedeu-se a coleta e tratamento dos dados primários e secundários. A coleta de dados primários se deu por meio de entrevistas semiestruturadas e secundários por pesquisas bibliográfica e documental, que buscou elucidar o problema proposto sobre como se dá a utilização das estratégias políticas pelo ME na formação de políticas públicas de transporte na RMGV. Após as análises, são identificados os momentos de crise ocorridos em 2011, 2013 e 2015 que serviram de pano de fundo a atuação do ME. Em relação aos atores sociais envolvidos em políticas públicas de transporte na RMGV, foram identificados e analisados seus recursos de poder e suas estratégias políticas. Verificou-se que o movimento estudantil utiliza-se principalmente de estratégias conflitivas, e que seus objetivos nem sempre são alcançados. Portanto, a partir da perspectiva da linha de pesquisa em Gestão de Operações no Setor Público, que busca compreender a importância da qualidade nas operações de serviços e estuda a importância do planejamento no setor público por meio de elaboração de projetos, foram apresentadas, como produto final deste trabalho, proposições que visam indicar ao ME formas alternativas de acesso aos recursos de poder e uso de estratégias políticas para empoderamento dos estudantes enquanto atores sociais e melhor efetividade na formação de políticas públicas de transporte na RMGV. Palavras chave: Políticas Públicas. Movimento Estudantil. Recursos de Poder. Estratégias Políticas.
70

Translational contactless power supply systems with ultrasonic frequencies

Barnard, Jacobus Marthinus 27 November 2012 (has links)
D.Ing. / In this thesis, contactless power transmission with sliding transformers to mobile loads is investigated. The sliding transformer comprises an extended primary winding - placed along the path of travel - which is fed through a core containing a secondary winding and which is attached to a mobile load. In the first chapter problems with existing power supply systems are discussed whereafter several possible applications of such a system are identified. In this chapter different methods of obtaining contactless power transmission are also discussed and a brief discussion of a practical, cost effective system is given. In chapter two the application of different resonant topologies to compensate the large structural inductance of the sliding transformer is investigated. A Series Resonant, Series Loaded topology is identified as the most practical and efficient topology for this application and a more detailed analysis of this topology - as applied to this case - is given. Formulas to calculate the sliding transformer parameters are given in the third chapter and two quantities relating the optimization of sliding transformers to the parameters thereof, are defined. Methods to optimize sliding transformers in terms of these two quantities, and also with respect to EMI, are also discussed in this chapter. The design of a five meter long experimental system which delivers 15 kVA to a mobile load is given in chapter four and experimental results of this system are presented. In chapter five a detailed investigation into different output power control methods is conducted. The effect of these control methods on EMI is investigated by means of numerical simulation of a Series Resonant, Series Loaded system under these different control methods. The most complex control method which generates the most EMI, namely frequency and pulse burst control, is implemented into the experimental system to investigate the limitations thereof. Experimental results of this controlled system are presented. It is found that this control method increases the control range obtainable with classical frequency control but introduces many limitations due to discontinuous primary current. It is concluded in the last chapter that it is possible to optimize sliding transformers within achievable cost constraints to such an extent that such systems have acceptable efficiencies and that reasonable system lengths are obtainable.

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