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.

Detection of damped sine waves in a magnestostrictive displacement transducer using pretrigger and detection thresholds of opposite polarity

Abstract: A damped sine wave detector for detecting the response of a magnetostrictive displacement transducer. A pretrigger comparator compares the signal to a predetermined negative threshold. A signal comparator compares the input signal to a predetermined positive threshold. The pretrigger comparator turns on a pretrigger flip-flop and starts a delay timer when the input signal falls below the predetermined negative threshold. The pretrigger flip-flop supplies the data input of a signal flip-flop. The signal flip-flop is clocked by the signal comparator when the input signal is above the predetermined positive threshold. The signal flip-flop turns on if clocked and the pretrigger flip-flop is on. The detector includes two timers for resetting the flip-flops. An inhibit timer resets both flip-flops upon expiration of an inhibit time longer than the maximum expected duration of the damped sine wave signal. A delay timer resets only the pretrigger flip-flop after a delay time greater than the maximum expected interval between when the damped sine wave falls below the predetermined negative threshold and when the damped sine wave rises above the predetermined positive threshold. Thus the circuit is less sensitive to noise.

A new phase model for sinusoidal transform coding of speech

Abstract: A phase modeling algorithm for sinusoidal analysis-synthesis of speech is presented, where short-time sinusoidal phases are approximated using a combination of linear prediction, spectral sampling, delay compensation, and phase correction techniques. The algorithm is different to phase compensation methods proposed for source-system LPC in that it has been tailored to sinusoidal representation of speech. Performance analysis on a large speech data base reveals an improvement in temporal and spectral signal matching, as well as in the subjective quality of reconstructed speech. The method can be applied to enhance phase matching in low bit rate sinusoidal coders, where underlying sine wave amplitudes are extracted from an all-pole model. Preliminary subjective results are presented for a 2.4 kb/s sinusoidal coder.

Method of producing trunks type wearing articles

Abstract: Central bodies (6, 7) forming the crotch of a trunks type wearing article (1) are respectively fabricated from first and second subsheets obtained by bisecting the width of a web along a quasi sine curve, the web being continuously fed in one direction. The first and second subsheets are joined together at their crests of the lateral edges describing the quasi sine curve so as to form a laminated sheet, which is then cut widthwise.