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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.
31

Warm electron magneto-microwave polarization studies in indium antimonide

Newman, Harvey S., January 1980 (has links)
Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 135-139).
32

Die experimentelle untersuchung der kommutationsvorgänge in gleichstrommaschinen ...

Czeija, Karl. January 1903 (has links)
Inaug.-dis.--Karisruhe.
33

Inrush currents of single phase transformers with nonlinear loading

Hasan, Mohammad Mozaffarul. January 1960 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1960. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 62-63).
34

Optimal pricing of transmission services

Perera, B. L. P. P. January 1994 (has links)
No description available.
35

A computer program for surge tank analysis

Parmley, Leslie James January 1960 (has links)
A method of solving surge tank problems with an electronic digital computer is presented in this thesis. The basic differential equations governing the transient behavior of the water mass in a surge tank system are developed in dimensionless form. A program prepared for the ALWAC III E computer at the University of British Columbia, solves these equations by a numerical integration process of the Runge-Kutta type. This program is suitable for the solution of a wide range of surge tank problems involving a single surge tank either upstream or downstream of the power unit in a hydroelectric installation. Solutions for the three basic types of surge tanks (simple, restricted orifice, or differential tank) under any of the three conditions for turbine discharge (flow, gate or power variation) are possible. The surge tank geometry and system coefficients may be altered to suit any particular circumstance. Also, the program contains a procedure which allows the incorporation of a variable turbine efficiency term in the calculations. Several numerical examples are included to illustrate the use of this program. A copy of the program tape is on file with the Department of Civil Engineering at the University of British Columbia. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
36

Three Essays on the Economics of Competitive Electricity Market

Olayinka, Williams January 2015 (has links)
In this thesis we present three essays on the economics of competitive electricity. In chapter one we use a stochastic dynamic model to examine the economic impact of storing wind power in a hydroelectric reservoir. Using a stochastic dynamic model allows us to explicitly model the uncertainty of wind power in the objective function of the hydroelectric generator. We show that the amount of water released by the hydroelectric generator in any period is a decreasing function of the number of periods that the hydroelectric generator has to deplete its reservoir. Furthermore if the hydroelectric generator has a high enough number of periods to deplete the water in its reservoir it will be optimal for it not to release any water at the beginning. In chapter two we present a model of operating reserve in a competitive electricity market. Our paper departs from other papers in several respects. First, we concentrate on the possibility of generator failure and not demand uncertainty. Second, we allow demand to be highly inelastic rather than perfectly inelastic like other papers do. This allows price spikes to occur when there is a major generator failure. To moderate price spikes, options for operating reserves can be purchased and exercised when price spikes occur. Third, we model uncertainty on the supply side and not on the demand side. Fourth we adopt a two price approach where one price is used to reserve capacity and the other price is the strike price paid when the options are exercised unlike other models which use the spot price as the strike price. Finally we explicitly model the demand and supply in the market. Using the concept of rational expectation we develop and prove the existence and uniqueness of a rational expectations equilibrium and analyse its characteristics. Furthermore we show that the competitive electricity market will provide more operating reserve capacity than is socially optimal. In the chapter three we formalize a model of reliability for an electric grid when consumers’ preferences for electricity consumption are private information. In our model we design an optimal blackout strategy for the regulator. The model demonstrates that an ex post efficient social choice function is truthfully implementable in Bayesian Nash equilibrium. It also yields both the optimal level of generation capacity investment and the second-best blackout program.
37

A statistical investigation of electric breakdown in askarel /

Rudinskas, Victor Edwin January 1977 (has links)
No description available.
38

Visual localisation of electricity pylons for power line inspection

Ali, Emmanuel Yahi 08 September 2023 (has links) (PDF)
Inspection of power infrastructure is a regular maintenance event. To date the inspection process has mostly been done manually, but there is growing interest in automating the process. The automation of the inspection process will require an accurate means for the localisation of the power infrastructure components. In this research, we studied the visual localisation of a pylon. The pylon is the most prominent component of the power infrastructure and can provide a context for the inspection of the other components. Point-based descriptors tend to perform poorly on texture less objects such as pylons, therefore we explored the localisation using convolutional neural networks and geometric constraints. The crossings of the pylon, or vertices, are salient points on the pylon. These vertices aid with recognition and pose estimation of the pylon. We were successfully able to use a convolutional neural network for the detection of the vertices. A model-based technique, geometric hashing, was used to establish the correspondence between the stored pylon model and the scene object. We showed the effectiveness of the method as a voting technique to determine the pose estimation from a single image. In a localisation framework, the method serves as the initialization of the tracking process. We were able to incorporate an extended Kalman filter for subsequent incremental tracking of the camera relative to the pylon. Also, we demonstrated an alternative tracking using heatmap details from the vertex detection. We successfully demonstrated the proposed algorithms and evaluated their effectiveness using a model pylon we built in the laboratory. Furthermore, we revalidated the results on a real-world outdoor electricity pylon. Our experiments illustrate that model-based techniques can be deployed as part of the navigation aspect of a robot.
39

Étude des paramètres affectant l'impédance électrique de certains métaux et minéraux

Lambert, Roger. January 1974 (has links)
No description available.
40

Dielectric strength of air, and suspension type insulators.

McNaughton, Andrew G. January 1912 (has links)
No description available.

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