Topic
Sine wave
About: Sine wave is a research topic. Over the lifetime, 12183 publications have been published within this topic receiving 93013 citations. The topic is also known as: sinusoid.
Papers published on a yearly basis
Papers
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TL;DR: Motion capture suggests an important biological role for long-range apparent motion: the process serves to preserve continuity of object identity while at the same time eliminating spurious motion signals that arise from finer image features.
135 citations
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19 Jun 2001
TL;DR: In this article, a DC-to-AC inverter is used to control the amount of electrical power used to drive a cold cathode fluorescent lamp (CCFL) by driving a symmetrical rectangular waveform into a second-order low pass filter at the resonant frequency of the filter for all conditions of line voltage and delivered power.
Abstract: The described DC to AC inverter efficiently controls the amount of electrical power used to drive a cold cathode fluorescent lamp (CCFL). The output is a fairly pure sine wave which is proportional to an input control voltage. The output waveform purity is ensured by driving a symmetrical rectangular waveform into a second-order, low pass filter at the resonant frequency of the filter for all conditions of line voltage and delivered power. Operating stress on the step-up transformer is minimized by placing the load (lamp) directly across the secondary side of the transformer. When configured to regulate delivered power, the secondary side may be fully floated which practically eliminates a thermometer effect on the operation of the lamp. All of the active elements, including the power switches, may be integrated into a monolithic silicon circuit.
131 citations
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18 Jun 1995TL;DR: In this article, the output voltage control is structured around an inner filter capacitor current loop where capacitor current is sensed via a single, small current transformer, which avoids the expense of multiple, active current sensors.
Abstract: This paper presents a state space approach to the problem of controlling a single phase PWM inverter with an LC output filter. These types of inverter are often used in uninterruptable power supplies (UPS) where a sine wave output voltage is to be maintained. Output voltage control is structured around an inner filter capacitor current loop where capacitor current is sensed via a single, small current transformer. This avoids the expense of multiple, active current sensors found in alternative designs. Performance of the capacitor current loop is enhanced with active decoupling of both the DC bus and the equivalent "back-EMF" of the output voltage. The output dynamic stiffness of the system is analyzed and plotted. Experimental results yield less than 0.5% total harmonic distortion (THD) at full load (8 kW), with transient response times of less than 200 /spl mu/s. >
130 citations
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TL;DR: In this paper, Cai et al. used the frequency characteristic of the incident wave (a one-cycle sinusoidal wave) was overlooked in their previous study to study the effect of multiple parallel fractures on wave attenuation in rock masses.
129 citations
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TL;DR: In this article, a finite element method is used with an arbitrary Lagrangian-Eulerian formulation to handle the moving boundary problem of a two-dimensional thin draining film and the phase boundaries for this quasi-periodic regime have been determined through extensive numerical parametric search.
Abstract: Surface wave instabilities in a two-dimensional thin draining film are studied by a direct numerical simulation of the full nonlinear system. A finite element method is used with an arbitrary Lagrangian–Eulerian formulation to handle the moving boundary problem. Both temporal and spatial stability analysis of the finite-amplitude nonlinear wave regimes are done. As the wavenumber is decreased below the linear cut-off wavenumber, supercritical sinusoidal waves occur as reported earlier from weakly nonlinear analysis and experiments. Further reduction in wavenumber makes the Fourier spectrum broad-banded resulting in solitary humps. This transition from nearly sinusoidal permanent waveforms to solitary humps is found to go through a quasi-periodic regime. The phase boundaries for this quasi-periodic regime have been determined through extensive numerical parametric search. Complex wave interaction processes such as wave merging and wave splitting are discussed. In the exhaustive numerical simulations performed in this paper, no wave-breaking tendency was observed, and it is speculated that the complex wave-interaction processes such as wave merging and wave splitting curb the tendency of the film to break.
126 citations