5 results about "Frequency characteristic" patented technology

The invention discloses a disturbing force compensation method of a two-degree-of-freedom double electro-hydraulic vibrostand array simulation system. The two-degree-of-freedom double electro-hydraulic vibrostand array simulation system comprises a lower platform, a six-degree-of-freedom vibrostand, a two-degree-of-freedom vibrostand, a pier A, a pier B and a bridge board. According to the disturbing force compensation method disclosed by the invention, pressure difference signals of two chambers of hydraulic cylinders in 10 valve-controlled cylinder cylinders and acceleration signals of piston rods of the hydraulic cylinders are collected, and disturbing force compensation signals are obtained by calculation. Driving signals of the valve-controlled cylinder cylinders are adjusted by usingthe disturbing force compensation signals to achieve the purpose of improving the control precision of the array simulation system. By application of the disturbing force compensation method proposedby the invention, the fluctuation 6dB of amplitude-frequency characteristics of a closed-loop transfer function of a rolling degree-of-freedom position in the vicinity of 18 Hz can be reduced within2dB, and the fluctuation 16dB of the amplitude-frequency characteristics of the closed-loop transfer function of a pitching degree-of-freedom position in the vicinity of 35 Hz can be reduced within 4dB, and the control precision of the array simulation system is obviously improved.

A signal processing device comprises: a band detecting means for detecting a frequency band which satisfies a predetermined condition from an audio signal; a reference signal generating means for generating a reference signal in accordance with a detection band by the band detecting means; a reference signal correcting means for correcting the generated reference signal on the basis of a frequency characteristic thereof; a frequency band extending means for extending the corrected reference signal up to a frequency band higher than the detection band; an interpolation signal generating means for generating an interpolation signal by weighting each frequency component within the extended frequency band in accordance with a frequency characteristic of the audio signal; and a signal synthesizing means for synthesizing the generated interpolation signal with the audio signal.

There is provided an abnormality detection device and a fixing structure which are suitable for detecting an abnormality of a fastener such as a bolt or a nut. An abnormality detection device detects an abnormality of a fixing structure including a bolt, a nut, and a washer which include a conductor and fix steel plates to each other, and a spacer which includes an insulator and is disposed between the steel plates and the washer, the abnormality detection device including: a transmission antenna that radiates electromagnetic waves to the fixing structure; a reception antenna that receives electromagnetic waves reflected by the fixing structure; and an abnormality detector that changes a frequency of the electromagnetic waves radiated from the transmission antenna to acquire frequency characteristics of standing waves received by the reception antenna and detects an abnormality of the fixing structure by comparing the frequency characteristics with frequency characteristics in a normal state.

This invention discloses a large power MOS transistor and its process method with multi-silicon grating larger than silicon plane and simple process, which is based on the current process and removes the step two and three into the last two steps for operation to realize the process. This invention improves the multiple silicon shape to remain and improve the frequency characteristics.