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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.
91

Projeto, construção e caracterização de um modulador pulsado para a operação de uma válvula magnetron de potência

CARLETO, NIVALDO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:50:09Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:56Z (GMT). No. of bitstreams: 1 10558.pdf: 10529307 bytes, checksum: be6b9ffcdd1b8416d5246549ff0f8d3d (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
92

Estudo da propagacao de pulsos laser atraves de um sistema amplificador de pulsos ultracurtos para o desenvolvimento de um alargador temporal do tipo offner / Study of Laser pulses propagation through an ultrashort pulse amplifying systems for the development of an Öffner temporal stretcher

CORDEIRO, THIAGO da S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:35Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:11Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
93

Projeto, construção e caracterização de um modulador pulsado para a operação de uma válvula magnetron de potência

CARLETO, NIVALDO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:50:09Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:56Z (GMT). No. of bitstreams: 1 10558.pdf: 10529307 bytes, checksum: be6b9ffcdd1b8416d5246549ff0f8d3d (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
94

Estudo da propagacao de pulsos laser atraves de um sistema amplificador de pulsos ultracurtos para o desenvolvimento de um alargador temporal do tipo offner / Study of Laser pulses propagation through an ultrashort pulse amplifying systems for the development of an Öffner temporal stretcher

CORDEIRO, THIAGO da S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:35Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:11Z (GMT). No. of bitstreams: 0 / Foi feito o estudo da propagação de pulsos laser através de um sistema amplificador de pulsos ultracurtos com meios dispersivos e modificadores de banda espectral. Deu-se ênfase à concepção de um alargador (ou alongador) de pulsos ultracurtos para substituir o já existente no sistema CPA híbrido de Ti:Safira/Cr:LiSAF em operação no Centro de Lasers e Aplicações do IPEN/CNEN-SP. Fez-se o desenvolvimento teórico e o estudo de um alongador temporal do tipo Öffner, livre de aberrações esféricas, objetivando obter uma razão de alargamento superior à existente no sistema em operação. Estudou-se também a influência das componentes de fase do sistema na duração final dos pulsos amplificados, e o sistema atual teve seus componentes limitantes de largura de banda mapeados, com o objetivo de conhecer as condições nas quais um novo alongador temporal deve ser inserido no sistema. Com base nessas medidas, foram implementadas rotinas computacionais para se determinar as consequências da passagem de um pulso por um componente limitante de largura de banda. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
95

EXPERIMENTAL INVESTIGATION OF RAPID FLOW TRANSIENTS IN AN INLET/COMPRESSOR SYSTEM, INDUCED BY SHORT-DURATION ACOUSTIC AND ENTROPY DISTURBANCES

OPALSKI, ANTHONY BENEDICT 21 May 2002 (has links)
No description available.
96

A pulse-width-modulated controlled-transformer post regulator

Sun, Ning 24 January 2009 (has links)
The theory of operation of a controlled transformer is described. A PWM controlled transformer is proposed and implemented in a forward converter to provide post regulation. Experimental results are presented to verify the new control scheme. Overall efficiency of 82%-86% is achieved in a 200khz, 500-watt, 5V-output off-line regulator. A discussion of design issues of the controlled transformer is also presented. / Master of Science
97

Investigation of the quality of frequency modulation produced by a sinusoidal variable condenser

Hoyt, Paul Richard. January 1932 (has links)
Call number: LD2668 .T4 1932 H65
98

A NEW DATA PROCESSING TECHNIQUE OF PPM/PPK WITHOUT THE REFERENCE PULSE

Xi-Hua, Li 11 1900 (has links)
International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper describes the technical principle that signals conversion, data-processing and data storage are directly carried out without filling up with the reference pulse for PPM and PPK (pulse position keying). By means of analysis for typical frame structure of PPM/PPK signals, a variety of math models of signal time relationship of the system were found, and based on this, a engineering way and a principle block diagram for signals conversion, data processing and data storage were given out.
99

Pulse compression filter design for ultrasonic non-destructivetesting

林鴻耀, Lam, Hung-yiu. January 1994 (has links)
published_or_final_version / Electrical and Electronic Engineering / Master / Master of Philosophy
100

Generic foundations of envelope solitons and some application areas

Putman, Richard Charles John January 1997 (has links)
No description available.

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