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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

Dinamica e controle de um gerador de vapor do tipo passo-unico

GOMES, ARIVALDO V. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:25:58Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:24Z (GMT). No. of bitstreams: 1 00988.pdf: 3339929 bytes, checksum: 27ead5c2fe041a5b93b6fa5c9a4df73f (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
262

Distribuicao de temperatura da baia de Piraquara de Fora, resultante da liberacao do calor residual da central nuclear almirante Alvaro Alberto em Angra dos Reis e seus possiveis efeitos ecologicos

SINGER, EUGENIO da M. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:00Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:49Z (GMT). No. of bitstreams: 1 11265.pdf: 2929018 bytes, checksum: 9a8d3e1d93adb583d2ea91814a4100de (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
263

Avaliacao da integridade do vaso de pressao dos reatores Angra II/III pela analise de tensoes

GOMES, EDSON 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:03Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:10Z (GMT). No. of bitstreams: 1 00721.pdf: 1565696 bytes, checksum: 317165c778a10488d3c186dc5f2ba1fc (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA
264

The influence of outsourcing the core deliverables on the business performance at Eskom Distribution South Africa

Magagula, Marcia January 2017 (has links)
Submitted in fulfilment of the requirements for Degree of Master of Management Sciences: Business Administration, Durban University of Technology, 2017. / The execution of maintenance and repairs are the core business deliverables of the Power Plant Maintenance (PPM) department at Eskom Distribution South Africa (SA). However, external service providers are employed to similarly execute these deliverables. Given this background, this study aimed to determine the influence of outsourcing core deliverables on the performance of the PPM department at Eskom SA. This quantitative study sought to determine the prevalence of any statistically significant differences in the degree of respondents’ responses regarding outsourcing the core business deliverables of their respective PPM departments in terms of profile factors such as gender, marital status, age, education qualification, designation and length of service. The study was carried out in eight out of nine PPM departments. A total of 135 responses were attained from a possible 152 participants, providing a response rate of 89 percent. The study was successful in the achievement of all the objectives. The results of the chi-square and regression tests revealed the presence of significant factors contributing to the outsourcing of core business deliverables, accomplishing the first objective. The results of the chi-square and correlation tests revealed that outsourcing did effect business performance, though this was not generally an enhancing effect, accomplishing the second objective. Results of the chi-square tests also highlighted significant effects on the motivation of internal employees when the repairs and maintenance of the power plant equipment are outsourced, accomplishing the third objective. The results of the correlation and chi-square also highlighted the effect of managing the core business deliverables on the business performance, the motivation of internal employees, as well as the alleviation of significant risks resulting from outsourcing core deliverables. The coefficient of determination (R-squared) revealed only 33 percent of the variations in the dependent variable that were explained by the independent variables. Finally, there was an indication of statistically acceptable reliability for the variables of the study. / M
265

The economic and policy aspects of small hydro development in British Columbia

Croll, Geoffrey Edward George January 1990 (has links)
Small hydropower offers many advantages as a source of energy and it has been successfully developed by the private sector in the U.S. and in Ontario. Although there is considerable interest in developing British Columbia's vast small hydro resource, there has been very little progress to date. The reasons for this are related more to economic and political factors than to technical issues. In this thesis I review the situation in B.C. and propose a policy framework for energy purchase price, one of the main issues involved in small hydro development. The price offered small hydro producers for their electricity is clearly less than B.C. Hydro's avoided cost, but there is little evidence to support the amount offered. I suggest that, in the absence of an established, competitve market, energy purchase rates should be based on the utility's avoided costs, and that avoided costs be determined by amortizing the capital costs of the next scheduled project over a 20 year period, rather than basing them on the average levelized costs of all future projects. Furthermore, small hydro development should take a two-stage approach, similar to Ontario's, whereby energy is initially purchased at the utility's full avoided cost and later, when the small hydro industry has had a chance to develop, energy would be purchased at market value or through a competitive bidding process. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
266

The costing and financing of the 'proposed OTEC plants'

Tandon, Jitendra N. January 1979 (has links)
Thesis: M.S., Massachusetts Institute of Technology, Department of Ocean Engineering, 1979 / Bibliography: leaves 165-168. / by Jitendra N. Tandon. / M.S. / M.S. Massachusetts Institute of Technology, Department of Ocean Engineering
267

Seismic performance risk analysis for nuclear power plants as input to design decisions

Al-Geroushi, Rajab A. January 1982 (has links)
No description available.
268

Digital Computer Analysis of the Kinetic Response of a Thermal Pressurized Water Reactor Power Plant

Alburger, John F. 01 January 1978 (has links) (PDF)
A digital computer model has been developed to simulate the kinetic response of a thermal pressurized water reactor power plant. The program is capable of predicting core power and plant temperature variations which result from disturbances due to routine demand changes, control rod movement, and fission product poison transients as well as from transients during plausible accident situations. The development of the differential equations describing the influence of various primary plant components on the dynamics of the reactor have been heretofore documented in the literature. Finite difference equations facilitating the employment of a digital computer solution are fully derived. Confidence in program validity is supported by the simulation of previously studied accidents and comparison with the safety analyses of a licensed nuclear power generating plant. A source listing of the computer program is provided in the Appendix.
269

Site selection for electrical receiving stations

Smythe, Terrence T. January 1984 (has links)
Call number: LD2668 .T4 1984 S625 / Master of Landscape Architecture
270

SOME NEW TECHNIQUES FOR THE LOAD FREQUENCY CONTROL OF MULTI-AREA POWER SYSTEMS.

ABDULLA, ABDULLA I. M. January 1986 (has links)
In this dissertation, the problem of multi-area load frequency control in large power systems is investigated. The load frequency control problem is concerned with the minimization of the deviations in the frequencies of the different areas and in the tie line power exchange between these areas, and is a problem of major importance in the satisfactory operation of large power systems. Some new techniques for designing load frequency control systems are presented through the use of concepts from singular perturbation and hierarchical system theory. To provide appropriate vehicles for the design of the new control systems, state variable models for power systems are developed. These models progress from a two-area interconnected power system model to large scale models comprising of N areas. Two centralized state feedback schemes are proposed for the load frequency control by utilizing the separation of the system models into two time scales. In the first scheme, composite controls and reduced order controls are developed to meet the required performance specifications by. The second scheme is obtained by using the theory of variable structure systems where the existence of a sliding regime leads to the design of a single discontinuous state feedback controller that meets the performance requirements. In order to further improve the performance of the closed loop system, a two level hierarchical control scheme is developed. This consists of a set of local controllers that are designed using either the singular perturbation approach or the variable structure system approach as before and a set of global control functions provided by a higher level controller that attempts to coordinate the local controllers. The interaction prediction principle is used as a tool in the design of the global controller. The performance of the presently developed control schemes is examined in detail for the illustrative cases of a two-area and a three-area power system. From this analysis, it is shown that these controllers provide an improved performance compared to the existing control schemes in reducing the frequency and tie line power deviations.

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