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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.
91

Problems of the fossil-energy economy and the possible implications of alternative energy sources for planning future Australian settlements /

Hume, David Edward. January 1978 (has links) (PDF)
Thesis (M.U.R.P. 1979) from the Department of Architecture, University of Adelaide. / Includes bibliographical references (p. 165-188).
92

Three essays on the electricity spot and financial derivative prices at the Nordic Power Exchange

Deng, Daniel. January 2006 (has links)
Thesis (doctoral)--Göteborgs Universitet, 2006. / Added t.p. with thesis statement inserted.
93

Energy management in a telecommunications environment with associated energy and cost modelling of HVAC

Rabie, Neil. January 2005 (has links)
Thesis (M.Eng.(Electrical Engineering))--University of Pretoria, 2001. / Summaries in Afrikaans and English. Includes bibliographical references.
94

Essays on restructured electricity markets

Nicholson, Emma Leah. January 2008 (has links)
Thesis (Ph.D.)--Georgetown University, 2008. / Includes bibliographical references.
95

Power and energy geopolitical aspects of the transnational natural gas pipelines from the Caspian Sea basin to Europe /

Benke, Ildiko. January 2010 (has links) (PDF)
Thesis (M.S. in Defense Analysis)--Naval Postgraduate School, June 2010. / Thesis Advisor(s): Tsypkin, Mikhail ; Second Reader: Lober, George. "June 2010." Description based on title screen as viewed on July 14, 2010. Author(s) subject terms: Natural gas, transportation routes, pipelines, power rivalry, energy demand, energy resources, energy policy, energy security, post-Cold war era, Caspian Sea basin, Russian periphery, geopolitical, littoral states, political instability. Includes bibliographical references (p. 53-56). Also available in print.
96

Three essays on the electricity spot and financial derivative prices at the Nordic Power Exchange /

Deng, Daniel. January 2006 (has links)
Thesis (doctoral)--Göteborgs Universitet, 2006. / Added t.p. with thesis statement inserted. Includes bibliographical references.
97

Physics-Based Modeling of Power System Components for the Evaluation of Low-Frequency Radiated Electromagnetic Fields

Barzegaran, Mohammadreza 07 March 2014 (has links)
The low-frequency electromagnetic compatibility (EMC) is an increasingly important aspect in the design of practical systems to ensure the functional safety and reliability of complex products. The opportunities for using numerical techniques to predict and analyze system’s EMC are therefore of considerable interest in many industries. As the first phase of study, a proper model, including all the details of the component, was required. Therefore, the advances in EMC modeling were studied with classifying analytical and numerical models. The selected model was finite element (FE) modeling, coupled with the distributed network method, to generate the model of the converter’s components and obtain the frequency behavioral model of the converter. The method has the ability to reveal the behavior of parasitic elements and higher resonances, which have critical impacts in studying EMI problems. For the EMC and signature studies of the machine drives, the equivalent source modeling was studied. Considering the details of the multi-machine environment, including actual models, some innovation in equivalent source modeling was performed to decrease the simulation time dramatically. Several models were designed in this study and the voltage current cube model and wire model have the best result. The GA-based PSO method is used as the optimization process. Superposition and suppression of the fields in coupling the components were also studied and verified. The simulation time of the equivalent model is 80-100 times lower than the detailed model. All tests were verified experimentally. As the application of EMC and signature study, the fault diagnosis and condition monitoring of an induction motor drive was developed using radiated fields. In addition to experimental tests, the 3DFE analysis was coupled with circuit-based software to implement the incipient fault cases. The identification was implemented using ANN for seventy various faulty cases. The simulation results were verified experimentally. Finally, the identification of the types of power components were implemented. The results show that it is possible to identify the type of components, as well as the faulty components, by comparing the amplitudes of their stray field harmonics. The identification using the stray fields is nondestructive and can be used for the setups that cannot go offline and be dismantled
98

Measuring energy consumption characteristics in mobile data communication

Thomasson, Anton January 2011 (has links)
This report looks at the modern cellular wireless network environment and the factors of energy consumption therein. The consumption of connectivity re- lated hardware is gradually becoming a larger part of the power consumption of virtually any mobile device. This report studies measurements of a mobile broadband module energy usage due to data transfer. It is found that switch- ing between technologies is still beneficial and savings are very feasible when using technologies with different traits if done correctly. Further the possibility of energy savings within a single high-bandwidth technology (3G) are assessed considering variations on response time and throughput. This is relevant as the need to handle highly dynamic loads becomes more and more important in the modern connectivity landscape. By gauging the savings available from schedul- ing link accesses and switching technology this is put in context by sampling a few common services namely Skype, Spotify and normal web browsing for their energy footprints. We will also look briefly at the background traffic generated by two common operating systems, Windows 7 and Ubuntu GNU/Linux.
99

The Analysis and Study of Power System Designs for Same Polytechnic College in Tanzania

Hua, Kevin Lum 01 June 2018 (has links)
The Mbesese Initiative for Sustainable Development (MISD) is a group aiming to help eliminate extreme poverty in Africa by creating educational opportunity. One project that the group is currently doing is to build Same Polytechnic College (SPC) in Tanzania. As part of the project, this thesis aims to study and analyze the electrical power system and distribution for the college. Based on the projected load profile of the college and high potential for solar generation in Tanzania, several different power systems utilizing local utility AC electricity and/or photovoltaic (PV) DC electricity are explored and simulated for their feasibility and performance. Analysis of each design is presented and compared to determine the most viable system based on reliability, costs, and space. Results of the study indicate that over designing the DC system may generate wasteful energy while under designing the DC system may cause the overall system to rely heavily on the AC power grid. Ultimately, this thesis demonstrates that integrating a 58.9% DC system mixed with AC system offers the highest payback while efficiently utilizing the PV system, the battery system, and provided land.
100

Photovoltaic Emulator Adaptable to Irradiance, Temperature and Panel Specific I-V Curves

Durago, Joseph Gamos 01 June 2011 (has links)
This thesis analyzes the design and performance of a photovoltaic (PV) emulator. With increasing interest in renewable energies, large amounts of money and effort are being put into research and development for photovoltaic systems. The larger interest in PV systems has increased demand for appropriate equipment with which to test PV systems. A photovoltaic emulator is a power supply with similar current and voltage characteristics as a PV panel. This work uses an existing power supply which is manipulated via Labview to emulate a photovoltaic panel. The emulator calculates a current-voltage (I-V) curve based on the user specified parameters of panel model, irradiance and temperature. When a load change occurs, the power supply changes its current and voltage to track the calculated I-V curve, so as to mimic a solar panel. Over 250 different solar panels at varying irradiances and temperatures are able to be accurately emulated. A PV emulator provides a controlled environment that is not affected by external factors such as temperature and weather. This allows repeatable conditions on which to test PV equipment, such as inverters, and provides a controlled environment to test an overall PV system.

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