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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.
311

Aged Electricity Distribution Asset Replacement

McFarlane, Andrew Ian January 2014 (has links)
Major segments of the Marlborough Lines Ltd (MLL) 11kV electricity distribution network are positioned within remote areas of the Marlborough region including the Marlborough Sounds, the Awatere and Wairau Valleys and the North Eastern cost of the South Island. The majority of these remote rural lines are due for replacement within the coming 20 years in order to maintain safety and reliability. The increased maintenance costs of operating rural electricity lines and the number of customers they serve often results in the line being uneconomic to operate. This investigation determines the current economical efficiency of the Sounds Feeder, a segment of line in the Marlborough Sounds. The financial, social and regulatory implications of the continued operation of this section of the network after performing distribution renewals are assessed in order to define the likely impacts of wide spread asset renewal to MLL and its customers across the coming 20 years.
312

The aerodynamics of shrouded multistage turbines

Lewis, Kendrick Lloyd January 1993 (has links)
No description available.
313

Electromagnetic coupling by a wire penetrating a circular aperture in an infinite planar conducting screen

Lee, Robert, 1962- January 1988 (has links)
We consider the problem of electromagnetic propagation along a wire which passes through an aperture. We begin by formulating an integral equation in terms of the electric field at the aperture. The solution of the integral equation allows us to determine parameters of interest such as the equivalent admittance, the current on the wire, and the electric field. We solve the integral equation using both a zeroth order and method of moments approximation for the aperture field. From this we are able to compute the admittance and current in the frequency domain. We next calculate the current response to a transient pulse excitation. The results show that the screen provides little shielding from pulse penetration along the wire. Finally, we calculate solutions for the electric field. The results are given in several contour plots.
314

Electromagnetic coupling by a wire through a cavity-backed circular aperture in an infinite screen

Wright, Diana Beth, 1963- January 1988 (has links)
The problem of a wire penetrating a circular aperture in an infinite screen and coupling energy into a cavity behind that screen is considered. We formulate an integral equation in terms of the electric field in the aperture. This integral equation is solved using two approximate methods: a zeroth-order approximation valid at low frequencies, and the method of moments. In addition, we introduce an equivalent circuit model to aid in our physical interpretation of the problem. Numerical results for the interior current on the wire and for the equivalent circuit admittance parameters are presented in order to provide a comparison between the two approximations. Inside the cavity, we examine the components of the electric field as a function of position. Finally, the exterior magnetic field far from the aperture is studied as a function of frequency. We examine the relationship between interior resonance features associated with the presence of the cavity and observations of the exterior field.
315

Two-dimensional device simulation of junction termination structures for determination of breakdown behavior

Tan, Leong Hin, 1957- January 1989 (has links)
In this work, we have investigated numerical techniques to determine the breakdown behavior of complex semiconductor devices using two-dimensional simulation. In particular, we have augmented the device simulator SEPSIP with a capability for handling single and multiple floating field rings, and for handling devices with slanted edges. We have furthermore improved the grid width selection algorithm in SEPSIP. A capability for plotting equi-field contours was added to the code. Finally, all system dependencies were removed from the SEPSIP code, and a new version of SEPSIP (Version 2.0) was generated which can be executed on any PC/XT, PC/AT, or PC/386 compatible computer. This eliminates the need for transfering files back and forth between the PC, which had formerly been used as an I/O processor, and the VAX, which was used for numerically intensive computations. It also makes the code more accessible to scientists and engineers who are working in this important research area.
316

Game theory application to the analysis of wheeling charges allocation and bidding strategies

Lozano Moncada, Carlos Arturo January 2003 (has links)
No description available.
317

New Adaptive Load Shedding Scheme for the Abu Dhabi power system (UAE)

El-Banhawy, M. H. January 1988 (has links)
No description available.
318

Size Effect in the Electrical Conductivity of Bismuth

Vaughn, Bobby J. 08 1900 (has links)
If a physical dimension of a metallic specimen is comparable with, or smaller than, the mean free path of the conduction electrons, then the observed electrical conductivity will be less than that of a conventional bulk sample. This phenomenon is called a size effect, and is the result of electron scattering from the specimen surfaces. In the present investigation, measurements were made on electropolished monocrystalline specimens ranging from matchbox geometry to thick-film geometry in order to obtain further information on the size effect in bismuth at liquid helium temperatures.
319

An Evaluation of Ten Electricity Training System Laboratory Manuals to Ascertain their Adequacy in Meeting Curriculum Standards for the Secondary School Course: General Electricity

Turner, Richard M. 08 1900 (has links)
This study involved an evaluation of laboratory manuals available to high schools for use with electricity training systems to ascertain which-were most adequate in meeting curriculum standards for general electricity as specified in Bulletin 615 of the Texas Education Agency.
320

Současná situace na českém energetickém trhu: s důrazem na čtvrté regulační období Energetického regulačního úřadu / Current Situation on the Czech Electricity Market: with an Emphasis on the Fourth Regulatory Period of the Czech Energy Regulatory Office

Krška, Štěpán January 2014 (has links)
This thesis examines the current situation on the electricity market in the Czech Republic. A particular emphasis is put on the regulation of distribution system operators (DSOs). The Czech regulator applies only general efficiency factors for all incumbents, and the efficiency of the incumbents is not taken into account in the regulatory formula. In many countries, the regulators apply benchmarking methods to assess the efficiency of operators. This thesis analyses the current regulatory formula in international comparison and considers the application of benchmarking methods to the regulation of DSOs. The first part provides a description of the theoretical approach to the regulation of network industries, relevant legal norms, the current situation on the Czech electricity market and practices of the regulatory bodies in selected European states. The second, empirical, part presents an international benchmarking study based on data of 15 regional DSOs including two Czech operators. The study examines the application of yardstick methods using data envelopment analysis (DEA) and stochastic frontier analysis (SFA). Based on our results, we find that the cost efficiency of each of the Czech DSOs is different. This suggests that introducing individual efficiency factors in the fourth regulatory...

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