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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.
41

The nature of torsional interactions in synchronous generators /

Joós, Géza. January 1986 (has links)
No description available.
42

Molecular Design for Precise Sequence Control and Functions of Alternating Copolymers / 交互共重合体の配列精密制御と機能創出に向けた分子設計

Nishimori, Kana 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22470号 / 工博第4731号 / 新制||工||1739(附属図書館) / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 大内 誠, 教授 秋吉 一成, 教授 竹中 幹人 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
43

The nature of torsional interactions in synchronous generators /

Joós, Géza. January 1986 (has links)
No description available.
44

An Algebraic Foundation of the Calculus of Alternating Differential Forms / The Calculus of Alternating Differential Forms

Morton, Mary 10 1900 (has links)
This thesis is concerned with the calculus of alternating differential forms on a manifold. It establishes that this calculus is of a purely algebraic nature by developing its precise analogue for an arbitrary commutative algebra with unit over a field. / Thesis / Master of Science (MSc)
45

MULTI CHANNEL AC POWER MONITOR USING DIGITAL SIGNAL PROCESSING

Hicks, William T. 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / The monitoring of multi phase 400 Hz aircraft power includes monitoring the phase voltages, currents, real powers, and frequency. This paper describes the design of a multi channel card that uses digital signal processing (DSP) to measure these parameters on a cycle by cycle basis. The card measures the average, peak, minimum cycle, and maximum cycle values of these parameters.
46

Electrochemical Disinfection of Municipal Wastewater using Alternating Current

Chavez Reyes, Xavier A 18 December 2014 (has links)
This research focused on chlorine-free disinfection of wastewater by complying with today's regulations. The equipment used was a continuous flow electrochemical reactor connected to an alternating current (AC) power supply. The electrodes used were made out of titanium coated with iridium oxide. To determine the inactivation of Escherichia Coli, a bacterial count method based on the USEPA method 1603 was used. After several experiments it was determined that electrochemical disinfection using AC was not efficient and economic enough to be classified as a viable alternative to chlorine disinfection. It was demonstrated that chlorine can be produced by electrolysis using AC and that no hydrogen could be noticed as a byproduct of the electrolysis of wastewater. When the results from this investigation were compared to the ones obtained using DC in Acosta (2014), it was determined that the belief that AC and DC are equally efficient at disinfecting wastewater is wrong.
47

A PMAC motor drive with a minimum number of sensors / Li Ying.

Li, Ying, 1963 Mar. 3- January 2002 (has links)
"October 2002" / Bibliography: p. 219-228. / xi, 229 p. : ill. (some col.), plates (col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Proposes a robust indirect position sensing technique implemented in real time using a DSP based motor controller. This is based on a rotor position estimation using the measured phase voltages and currents of the motor. An incremental algorithm is used to estimate the flux linkage increments, which eliminates the integration involved in the flux linkage estimation. This feature provides a wider operating speed range and robustness. / Thesis (Ph.D.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 2002
48

Computerised dynamic control of an ac dynamometer

Rodrigues, Terence Keith 24 August 1998 (has links)
The Motor Systems Resource Facility (MSRF) at Oregon State University presently conducts a variety of steady state tests on Motors and Generators, with ratings of upto 300Hp.(225kW), using a dynamometer. The dynamometer consists of an induction motor fed by a power electronic converter. A control computer uses a serial link, to send the desired steady state values of speed or torque to the converter. The objective of the work of this thesis was the conversion of the existing control interface, to one that could support programmable dynamic operation. Some of the capabilities that the resulting system has acquired, include the ability to simulate a general, predefined torque or speed profile, from a generalised polynomial function, a sine wave of torque or speed added to a constant offset, and a general purpose mode which allows the user to specify an atypical profile. The conversion to dynamic operation, permits the study and laboratory simulation of dynamic effects like the Sub-Synchronous Resonance phenomenon observed in turbine- generator sets attached to the power grid, the effect of "tower shadow" on wind power generation, time-varying load profiles, testing of machines under real world operating situations etc. Several tests were performed to ensure that the actual speed/torque profiles obtained from the machine, corresponded to the reference profiles specified in each case. Measured performance of specific examples is given. / Graduation date: 1999
49

The Analysis and Simulation of compact-sized Antennas

Lin, Gang-Yi 21 July 2003 (has links)
In recent years, the demand for portable radio communication has been increasing which requires low profile, light weight and small size antennas. Therefore, the size of the antenna is required to be as small as possible. In this thesis, some of the compact antennas will be analyzed and simulated. The early-stage PIFA antenna will be investigated first, and then the shorting pin characteristics to design compact and dual band antenna was utilized. Because the shorting pin will lead to the decrease of bandwidth, replacement of the shorting pin by using chip-resistor could improve this characteristic. The compactness of antennas will lead to the decrease of the gain. In order to improve the gain of antennas, the combination of substrate and superstrate configuration with very high permittivity material is used. For the consideration of Bluetooth system, we use the ACPS (Asymmetrical Co-planar Striplines) structure to design the antenna. Using this structure in the design will obtain a promotion in bandwidth compared with the conventional rectangular microstrip antenna. Because the size of the antenna is small, the time to simulate this structure by the FDTD (Finite Difference Time Domain) method is too long. In order to solve this problem, this thesis mainly study a new FDTD algorithm based on the Alternating-Direction Implicit method, and use this algorithm to simulate some simple structures.
50

First principle calculation current density in AC electric field /

Zhang, Lei, January 2009 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2010. / Includes bibliographical references (leaves 64-67). Also available in print.

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