Harmonics Functions
Mostrando 1-12 de 12 artigos, teses e dissertações.
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1. Interferência de harmônicas em equipamentos de medição de energia elétrica. / Harmonic interference in equipment for measurement of eletrical energy.
This work addresses the reliability of energy meters in nonsinusoidal systems, looking for the increase of quality in the electric energy billing. To that purpose, it focuses on a fairer metering and a better relationship between the concessionaire and consumer. The tests were carried through in the laboratories of Eletropaulo, of the Electro-Technology and
Publicado em: 2009
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2. Diferentes noções de diferenciabilidade para funções definidas na esfera / Different notions of differentiability for functions defined on the sphere
In this work we study different notions of differentiability for functions defined on the unit sphere S^n-1 of R^n, n>=2. With respect to the usual derivative, we find necessary and/or sufficient conditions in order that a function be differentiable up to a fixed order. As for the other two, the strong Laplace-Beltrami derivative and the weak derivative, we
Publicado em: 2007
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3. Espaços de Poisson-Furstenberg e medidas invariantes para grupos de Lie semi-simples
Não informado.
Publicado em: 2005
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4. Algorithm not affected by frequency changes applied in digital generator protection. / Algoritmo imune a variações de freqüência aplicado à proteção digital de geradores.
The main pourpose of that work is inquire an adaptive algorithm to compensate the errors in the power system phasors calculation when occur significant changes in the frequency of the current and voltage signals. The main benefit of that technique is to permit errors compensation with constant sampling frequency and constant data window, making possible cons
Publicado em: 2005
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5. Investigações relativas ás linhas de transmissão horizontal e vertical de perdas elevadas
This document presents the laboratory measurements and time and frequency domain simulations and calculations regarding the high loss horizontal and vertical transmission lines aiming at improve the knowledge of their performance and well understand the electromagnetic interaction between the lightning channel and the electrical facilities. Impulsive and har
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 12/07/2004
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6. Narrow-band 1, 2, 3, 4, 8, 16 and 24 cycles/360º angular frequency filters
We measured human frequency response functions for seven angular frequency filters whose test frequencies were centered at 1, 2, 3, 4, 8, 16 or 24 cycles/360º using a supra-threshold summation method. The seven functions of 17 experimental conditions each were measured nine times for five observers. For the arbitrarily selected filter phases, the maximum su
Brazilian Journal of Medical and Biological Research. Publicado em: 2002-02
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7. Emergence of log-periodic oscillations in periodic and aperiodic Ising models
This work analyzes the emergence of log-periodic oscillations in thermodynamic functions of Ising models on hierarchical lattices. Several situations, where the exchange interactions are periodic or aperiodic, are taken into account. High precision values for the thermodynamic functions are numerically obtained with the method of transfer matrices. Fitting t
Brazilian Journal of Physics. Publicado em: 2000-12
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8. RESONANT OVERVOLTAGES DUE TO TRANSFORMER ENERGIZATION IN THREE PHASE SYSTEMS / ANÁLISE DE SOBRETENSÕES RESSONANTES DEVIDO A ENERGIZAÇÃO DE TRANSFORMADORES EM SISTEMAS TRIFÁSICOS
Transient overvoltages involving transformer energization, in three phase HV systems, deserve special attention in insulation coordination studies due to the very high values that voltages can reach in a period of a few seconds. Some resonant effects can possibly occur due to harmonics in the magnetizing inrush current. The objective of the present study is
Publicado em: 1982
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9. Stability of Plane Poiseuille Flow to Periodic Disturbances of Finite Amplitude, II
The stability of plane Poiseuille flow to periodic disturbances of finite amplitude was investigated by expanding each harmonic of the solution in terms of the Orr-Sommerfeld eigenfunctions with coefficients which are functions of time. The system of nonlinear ordinary differential equations for the coefficients was solved, and the number of harmonics N was
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10. Modeling source-filter interaction in belting and high-pitched operatic male singing
Nonlinear source-filter theory is applied to explain some acoustic differences between two contrasting male singing productions at high pitches: operatic style versus jazz belt or theater belt. Several stylized vocal tract shapes (caricatures) are discussed that form the bases of these styles. It is hypothesized that operatic singing uses vowels that are mod
Acoustical Society of America.
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11. Localization and function of the electrical oscillation in electroreceptive ampullary epithelium from skates.
A steady, spontaneous current oscillation (1 nA p-p) occurs in voltage-clamped, isolated ampullary organs (canal, ampulla, and nerve) from skates (Raja). Spectral analysis showed that energy in the oscillation was confined to a narrow band of frequencies (3 Hz) about a fundamental frequency (32 Hz at 20 degrees C) and in harmonics. The frequency of the oscil
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12. Interaction of apical and basal membrane ion channels underlies electroreception in ampullary epithelia of skates.
The exquisite sensitivity of elasmobranch fishes to electric fields is thought to reside in electroreceptive organs called ampullae of Lorenzini. We measured the stimulus-response behavior of ampullary organs excised from skates. Under open-circuit conditions, the ampullary organ showed three distinct response states: spontaneous repetitive spikes, evoked sp
The Biophysical Society.