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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.
81

The I3A Framework: enhancing the sustainability of off-grid photovoltaic energy service delivery in Indonesia.

Retnanestri, Maria Immaculata Taufi, Electrical Engineering & Telecommunications, Faculty of Engineering, UNSW January 2007 (has links)
Since the 1980s, approximately 10 MWp photovoltaic (PV) power has been installed in off-grid areas in Indonesia for powering lighting, water pumping, communications, health clinics, etc. However, PV energy systems (PVES) have yet to prove their sustainability and remain inaccessible to many remote Indonesian communities. The objective of this interdisciplinary thesis is to draw on social and engineering perspectives to address sustainability issues related to off-grid PVES delivery in Indonesia. By employing the Brundtland definition of sustainability, off-grid PVES delivery is analysed with respect to its institutional, financial, technical, social and ecological sustainability. In parallel, the thesis also investigates PVES Accessibility, Availability and Acceptability (3A), referring to the three energy goals proposed by the World Energy Council. The concepts of Sustainable Development, Social Capital, and Diffusion of Innovation are employed to examine the potential for off-grid PVES to contribute to improving the sustainability of remote Indonesian communities. The I3A (Implementation, 3A) Sustainable PVES Delivery framework is proposed to investigate PVES sustainability and the extent to which local communities can continue to socially innovate to meet their evolving needs beyond initial project completion. Sound project management (PM) is essential as off-grid PVES projects can only access limited resources (time, funds, and scope) and project failure can undermine a community???s capacity to innovate. The research methodologies include literature research, qualitative field research in villages where PVES has been installed and interviews with a wide range of PVES stakeholders in Indonesia. The I3A framework is tested against three off-grid PVES case studies from Lampung, West Java and NTT Provinces and is also proposed as a design tool. A key conclusion is that, to be sustainable and equitable, off-grid PVES projects should be implemented in an institutional framework that provides sound project management and addresses PVES accessibility (financial, institutional and technological), availability (technical quality and continuity) and acceptability (social and ecological). The overall objectives are to acknowledge the interests of all stakeholders, maximise equity, assure PVES continuity, and institutionalize PVES by utilizing and enhancing preexisting community resources to leave the community with the capacity to socially innovate. While this might be regarded as idealistic, enhanced local autonomy and capability will be essential in the context of the energy security and climate change challenges that humanity now faces.
82

The servey of channel transformation of Taiwan enterprise in China

Chan, Shu-ting 30 June 2008 (has links)
Abstract High quality powering systems have become the requirements for computers and electronic devices users. Uninterruptible power systems (UPS) are needed in office automation, home and small and medium enterprise computers and governmental network projects. In 2006, total UPSs sold in PRC exceeded 1,279 thousand units, with a sales value exceeding 2.61 billion RMB. The UPS industry experienced an 8% stable growth backed by economy growth of PRC. This research served theoretical basis and the understanding of industry practices as the base, describing the business model of UPS industry in PRC. This thesis also contains an in-depth interview with the leader of Powercom Co., an UPS manufacturer in PRC, on topics such as channel structure (length, width and density), relation control, channel motivation (strategy in effect and methods used) and conflict management (reasons, forms and solutions), trying to combine theories and practices. This study found that Powercom experienced three channel transformations in PRC market. Phase 1: instead of touching the market directly, they entered PRC via an agent, plays only the role of manufacturer ¡V a longer, narrower channel structure, with a traditional marketing relation aims at short-term profits, and price is the incentive. When the relation went down, Powercom took destructive solutions. Phase 2: Retailing channels were established in provinces in PRC, and the PRC market was divided in to four independent geographic marketing sectors, no intersection selling were allowed ¡V allowing the four sections to have their own storage and selling systems and compete with each other, resulting horizontal conflicts between section sellers. Phase 3: the marketing efforts are directed by a Great China concept, although the four offices still in charge of dealing orders and selling, no geographical restrictions exist. The channel structure was turned from density to selective distribution. Their relation with distributors are thus turned in to vertical systems, thus common objective, instead of price alone is the incentive to motivate firm members. Keywords: Uninterruptible power systems, cannel transformation
83

Model predictive control design for load frequency control problem

Atić, Nedz̆ad. January 2003 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains vii, 68 p. : ill. Includes abstract. Includes bibliographical references (p. 66-68).
84

Electri-city : reconfiguring the landscape of power

Lau, Hoi-ying, 柳凱瑩 January 2012 (has links)
published_or_final_version / Architecture / Master / Master of Landscape Architecture
85

The detailed design of a centralized computer system for backup protection and post-fault control, with particular emphasis onsecurity and reliability

Edgley, Ralph Kingsley. January 1975 (has links)
published_or_final_version / Electrical Engineering / Doctoral / Doctor of Philosophy
86

Economic dispatch with transmission limits using second derivative information

Bottéro, Marie-Hélène Eliane. January 1980 (has links)
No description available.
87

Analytic approach to economic dispatch

Fahmideh-Vojdani, A. (Alireza) January 1979 (has links)
No description available.
88

The minimum cost optimal power flow problem solved via the restart homotopy continuation method /

Ponrajah, Ranendra Anthony January 1987 (has links)
This thesis is the result of an investigation to assess the potential of the continuation method to solve the minimum cost optimal power flow problem. For this purpose, a restart homotopy continuation method algorithm is developed, which contains in essence two phases. / The pertinent steps of the first phase are as follows: (1) Create a sub-problem of the complete optimal power flow problem by relaxing boundary limits on all functional variables, namely voltages at load buses, line flows and reactive generations. (2) Parameterize a subset of the whole set of controls which comprises initially of tap-changers, phase-shifters, shunt controllers, and the voltages at generation buses. (3) Optimize the resulting problem. / The solution in step (3) is used as an initial starting point in a continuation process, designed to track this solution to the optimal solution of the sub-problem defined in step (1). The tracking is accomplished via a predictor-corrector path following algorithm embodying certain special features, such that the solution accuracy can be improved to any desired degree through a flexible restart feature developed in this study. Within the tracking process only a subset (identified in step 2 above) of the whole set of controls require specific monitoring for break-points. This feature greatly reduces the computational burden. Termination of the first phase marks an operating point in which all controls are strictly feasible. / If, following the termination of the first phase, functional variables previously ignored prove to be within their respective bounds, the solution to the sub-problem becomes the solution to the complete optimal power flow problem. However, should functional variables violate their bounds the second phase of the algorithm is invoked, which in essence creates a new sub-problem by changing the roles of the control and violated dependent variables, such that the newly modified sub-problem maintains the same basic structure as its predecessor. / Phase I is invoked again at this juncture to solve the modified sub-problem. This process is repeated in cycles until the Kuhn-Tucker optimality conditions are satisfied. Simulations suggest that convergence is usually achieved within two or three Phase I/II cycles. / This being a method unique to the minimum cost optimal power flow problem, numerous examples (up to 118 buses) have been tested and compared against the commercial code MINOS. The newly proposed algorithm appears to be faster and more reliable.
89

Power system harmonic state estimation

Zhang, Fan 05 1900 (has links)
No description available.
90

Fundamental understanding and integration of rapid thermal processing, PECVD, and screen printing for cost-effective, high-efficiency silicon photovoltaic devices

Doshi, Parag Mahendra 12 1900 (has links)
No description available.

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