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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.
261

Aspects of the ratio of reactive to real powers as input to transmission network control

Swart, Sarica Meyer 18 February 2014 (has links)
M.Ing. (Electrical Engineering) / Induction heating has been used in practice for many years. The main goal of this study is to investigate the use of a single-turn coil in a typical induction heater. The work starts off with a background study of elecrroheat and specifically high-frequency induction heating. Finite element simulations were conducted on different coil shapes and compared with each other. The converter. with control and driver circuits. used in the, experimental setup, as well as the experimental construction and results are described. The work is concluded with an evaluation of the project.
262

The fluid dynamic study of ducted and unducted Wells turbines in undirectional and oscillatory flows

Buttgereit, Ruediger Volker January 1998 (has links)
No description available.
263

General equations for short-range optimization of a combined hydro-thermal electric system

Arismunandar, Raden Artono January 1960 (has links)
This thesis offers a review and an analysis of all except the less important advances of the previously developed methods and equations for optimizing the operation of an electric system of m thermal and n hydro plants. In this analysis both short-range (twenty-four hours, seven days) and long-range (one year) periods are involved. The primary objective of this thesis is to derive, using the Calculus of Variations, general differential equations for short-range optimization of combined hydro-thermal systems. The basic criterion for choosing to solve the short-range instead of the long-term problem lies in the theory of forecasting in general, the theory of forecasting of stream flows in particular, and is based on the aforementioned analysis. Tests for establishing the fact that the above general equations actually produce the desired minimum cost of operation are given in the form of three other necessary conditions and three sufficient conditions. These conditions are known in this branch of mathematics as the analogue of Legendre's condition, the Weierstrass’ analogue of the Jacobi's condition and the Weierstrass' E-function condition for a minimum. A well-known example is worked out using these conditions. In addition to the above, this thesis also proves that all previously developed methods and equations for short-term optimization are essentially equivalent, and that these formulas are merely simplified forms of the general equations developed in this treatise. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate
264

Communication channel characteristics and behaviour of intrabuilding power distribution circuits

Chan, Morgan Hing-Lap January 1985 (has links)
Intrabuilding power distribution circuits offer a number of unique advantages for local area networking. To enable the selection of proper error-control codes and protocols for reliable data communication services, error pattern statistics of intrabuilding power line channels are obtained. Also, error-causing disturbances are identified and their relationships to specific types of error patterns are determined. It is found that error occurrence is highly periodic, with periodicity being a function of the power line frequency which is nominally 60Hz in North America. Furthermore, results indicate that error pattern behaviour is relatively insensitive to communication carrier frequency and modulation schemes. Based on the measurement results, hybrid ARQ with bit-interleaving is suggested for reliable data transmission at high data rate (19,200bps). Burst error correcting codes can be used to reduce decoder cost and complexity with some sacrifices in performance. At lower data rates (1,200bps or below), effective error control can be accomplished more easily. Finally, the attenuation characteristics of a number of typical power line channels are presented. It is found that high frequency bypass can be used to improve signal transmission between different phases of the distribution transformer. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate
265

Protective Relaying Student Laboratory

Pretzer, Kenan W 01 May 2017 (has links)
Facing a rapidly-changing power industry, the electrical engineering department at Cal Poly San Luis Obispo proposed Advanced Power Systems Initiatives to better prepare its students for entering the power industry. These initiatives call for the creation of a new laboratory curriculum that uses microprocessor-based relays to reinforce the fundamental concepts of power system protection. This paper summarizes a laboratory system fit for this task and presents a set of proposed laboratory experiments to establish a new laboratory course at Cal Poly. The experiments expose students to the capabilities of industry-standard microprocessor-based relays through hands-on procedures that demonstrate common power system protection schemes. Relays studied in this project support transformer, transmission line, and induction motor protection.
266

Ovládnutí prostoru novým nástrojem silové politiky: demokratizace / Mastering Space by New Mean of Power Politics: Democratization

Galtsova, Ksenia January 2020 (has links)
Democratization has been dominating international relations since the end of the Cold War. Moreover, democratization assistance became embedded in states' foreign institutions, as it is seen in the examples of the United States and the European Union. As states perceive international relations from a neo-realist perspective, it raises a concern about their reasoning behind democracy promotion. This thesis attempts to find a correlation between states' geopolitical objectives and democratization. Its goal is to prove that democratized countries tend to incline towards the assisting power, and this benefits the assisting power's geopolitical objectives. By studying EU and US geopolitical goals and applying them on the democratization of Ukraine, this thesis attempts to find how democracy promotion in Ukraine benefited the USA and the EU. To support the claim that ideology can be used to pursue geopolitical goals, it draws a parallel with the Communist coup d'état in Czechoslovakia in 1948 and analyzes how the USSR benefited from supporting the Czechoslovak Communist Party. Keywords Democratization, soft power, smart power, Cold War, communism, United States, European Union, USSR, geopolitics, democracy assistance
267

Derivation of Operational Intervention Levels for the early phase of radioactive material at Koeberg Nuclear Power Station

Trollope, Ian Douglas 29 January 2015 (has links)
A research report submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science, Joannesburg, 2014. / An investigation was performed to look at a method to develop easy to use field survey measurements to assist decision makers in the process of deriving public protective actions. This method could be used at a nuclear power plant if certain accident conditions are known. International values for operational intervention levels (OIL’s) do exist and are recommended to be employed if station specific data has not been derived. No values exist specific to Koeberg Nuclear Power Station and as a result, this became an ideal opportunity to derive station specific values. It was firstly necessary to decide on a specific accident type and hence an applicable accident release fraction. A suitable accident software dispersion code was applied to calculate the organ doses for the selected accident type. It was also decided to use two different wind dispersion criteria to further refine the results. Due to the complexities of dose distribution within the body it was also necessary to look at the gamma dose in isolation as this would be the measurement radiation type utilised as a limit in the field either using installed radiation monitors or by physical measurement performed by station Radiation Protection staff. Comparisons were done with thyroid and lung dose versus gamma dose to arrive at ratios for this specific accident type. This would then be indicative of the total dose to each organ as a result of a single field measurement. Conclusions were drawn on the results obtained and recommendations were made for when this type of data may be suitable for use in the unlikely event of a nuclear accident.
268

Having Responsible Power Leads to Sexual Harassment? The Explanatory Role of Moral Licensing

Dinh, Tuyen K. 10 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Feeling powerful or possessing power over someone is often shown in the sexual harassment literature as an antecedent. Indeed, power can be construed in a self-focused manner or in a responsibility-focused manner. Tost (2015) theorized that powerholders who construe their power as responsibility should then act for the benefit of others. However, a recent study by Stockdale, Gilmer, and Dinh (2019) found the opposite effect. Specifically, they found that priming responsibility-focused power increased the intention to sexually harass, speculating that priming such powers may have created a “moral license” (Miller & Effron, 2010) to engage in sexual harassment. The purpose of the present study is to extend their findings by examining the role of moral licensing. I hypothesize that participants who are in the responsibility-focused power priming condition will engage in sexual harassment proclivities through a serial mediation of communal feelings and moral licensing (moral crediting and moral credentialing). Results confirm that communal feelings and moral crediting serially mediate the relationship between responsibility-focused power and sexual harassment proclivities. The hypothesized role of moral credentialing was not supported. Findings in this study provides a potential explanation for the paradoxical findings of responsibility-focused power in Stockdale et al. (2019)’s study. This study also emphasizes the importance of understanding responsibility-focused power in sexual harassment indices and the potential the ironic effects of having such power via moral crediting.
269

Politique optimale pour l'interconnection d'un systeme hydroelectrique a un systeme thermique à l'aide de l'ordinateur digital.

Dupuis, Francis Yvon. January 1972 (has links)
No description available.
270

A knowledge based framework for procedure synthesis and its application to the emergency response in a nuclear power plant /

Sharma, Deva-Datta January 1986 (has links)
No description available.

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