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An extensión of the landau problem to quantum field theory
(2013)
The noncommutativity of spacetime is an old idea, which dates back to the 1930's and isattributed to Heisenberg. The idea was first developed by Snyder, who published his analysisin 1947 [1]. It has been revived in recent ...
A phase-shifting control for variable frequency multi-cells interleaved boost pre-regulator based on FPGA device
(IEEE, 2006-01-01)
In this paper were investigated phase-shift control strategies applied to a four cells interleaved high input-power-factor pre-regulator boost rectifier, operating in critical conduction mode, using a non-dissipative ...
A phase-shifting control for variable frequency multi-cells interleaved boost pre-regulator based on FPGA device
(IEEE, 2006-01-01)
In this paper were investigated phase-shift control strategies applied to a four cells interleaved high input-power-factor pre-regulator boost rectifier, operating in critical conduction mode, using a non-dissipative ...
Proposta, análise e implementação de técnicas de comutação sob tensão nula aplicadas a fontes cc-cc isoladas para telecomunicações
(Universidade Federal de Santa MariaBrasilEngenharia ElétricaUFSMPrograma de Pós-Graduação em Engenharia ElétricaCentro de Tecnologia, 2003-08-13)
Dc-dc isolated converters with Zero-Voltage-Switching are proposed and studied in this
thesis. Special attention is focused on converters with series switches connections, which
allow the use of switches designed for ...
Associação dos fatores psicossociais com o deslocamento ativo para a escola em adolescentes
(2020)
O objetivo do presente estudo foi estimar a prevalência do deslocamento ativo para a escola e investigar os correlatos intrapessoais (resultados esperados, atitude, autoeficácia) e interpessoais (apoio dos pais e apoio dos ...
Dimmable electronic ballast with high power-factor SEPIC preregulator, for multiple tubular fluorescent lamps
(2004-11-29)
An electronic ballast for multiple tubular fluorescent lamps is presented in this paper. The proposed structure features high power-factor, dimming capability, and soft-switching to the semiconductor devices operated in ...
Characterizing asymptotic randomization in abelian cellular automata
(Cambridge University Press, 2020)
Abelian cellular automata (CAs) are CAs which are group endomorphisms of the full group shift when endowing the alphabet with an abelian group structure. A CA randomizes an initial probability measure if its iterated images ...
Matrix-Valued Gegenbauer-Type polynomials
(Springer, 2017-12)
We introduce matrix-valued weight functions of arbitrary size, which are analogues of the weight function for the Gegenbauer or ultraspherical polynomials for the parameter ν> 0. The LDU-decomposition of the weight is ...
Dimmable electronic ballast with high power-factor SEPIC preregulator, for multiple tubular fluorescent lamps
(2004-11-29)
An electronic ballast for multiple tubular fluorescent lamps is presented in this paper. The proposed structure features high power-factor, dimming capability, and soft-switching to the semiconductor devices operated in ...