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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.
11

An expert system for economical electrical drive selection

Arain, Taj Mohammad January 1994 (has links)
No description available.
12

Extending the pump energy range for a pump-probe system using High Harmonics Generation

FLE, Guillaume January 2015 (has links)
No description available.
13

Using PSIM to investigate harmonic control for boost-type PWM rectifiers

Ehlers, PJ, Richards, CG, Nicolae, DV 01 January 2008 (has links)
Static power converters produce harmonics due to the nature of the conversion process. This paper will investigate two variations of current mode control for three-phase power converters ensuring reduced harmonic pollution and power factor improvement. The first method employed uses a Fryze current reference and the second method utilises a balanced three-phase sinusoidal reference. Both control techniques are simulated under unbalanced and distorted supply conditions using the PSIM simulation platform. The results are presented showing that using the Fryze current reference is the best choice.
14

An investigation on optimal current mode control for boost-type PWM rectifiers

Nicolae, DV, Ehlers, PJ, Richards, CG 02 March 2008 (has links)
Abstract-- Static power converters produce harmonics due to the nature of the conversion process. This paper will investigate the effect on the power factor of a sinusoidal and Fryze current reference on a PWM boost type rectifier. It has been shown in previous papers that a Fryze current ref is best. This paper will develop a mathematical model, based on the single sided Fourier expansion. Using this mathematical model it will be shown that even though a high harmonic content could be present in a Fryze controlled PWM boost type rectifier, the power factor has been optimally improved.
15

A spherical harmonic analysis of the global 1000 mb surface for September 1957.

Padro, Jacob January 1966 (has links)
Characteristic features of the long atmospheric waves are discussed on the basis of spherical harmonic analysis of global weather charts for September 1957. At first, there is a discussion of the Trapezoidal and Simpson's numerical integration rules as applied to the computation of the Spherical harmonic coefficients. [...]
16

Harmonic representation applied to large scale atmospheric dynamics.

Merilees, P. E. January 1966 (has links)
Spectral analysis (primarily in terms of spherical harmonics) is applied to the atmospheric dynamical equations in general, to truncated barotropic systems in particular and, in addition, to the global geopotential height field of the 500 mb surface for September 1957. [...]
17

Global shape description of digital objects /

Weistrand, Ola, January 2005 (has links)
Diss. (sammanfattning) Uppsala : Univ., 2005. / Härtill 4 uppsatser.
18

Die heineschen O-funktionen und ihre anwendungen auf die elliptischen funktionen ...

Ashton, Charles H. January 1909 (has links)
Inaug.-diss.--Munich. / Lebenslauf.
19

Ueber die invarianten eigenschaften spezieller binärer formen, insbesondere der kugelfunctionen ...

Hilbert, David, January 1885 (has links)
Inaug.-dis.--Königsberg.
20

Die heineschen O-funktionen und ihre anwendungen auf die elliptischen funktionen ...

Ashton, Charles H. January 1909 (has links)
Inaug.-diss.--Munich. / Lebenslauf.

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