查询词典 frequency analysis

According to the method, analysis and reconstruction sub-band filters for near perfect reconstruction oversampled filter bank are designed, then nonuniform multichannel loudness compensation based on human auditory, the sensitive feature of frequency and sound pressure level is implemented.

该方法研究了完美重构滤波器组分析与综合滤波器的设计方法，并根据人耳对频率的灵敏度特征及对声强的感知特性实现了符合人耳听觉特征的非等宽多通道响度补偿方案。

Through the simulation waveform of that analysis, design of the DAC0832 chip interface circuit to achieve a frequency of 762.9 HZ sawtooth.

通过对仿真波形图分析证明，设计的DAC0832芯片接口电路能实现频率为762.9HZ的锯齿波。

Secondly, making use of the good time frequency characteristics of the wavelet analysis in the signal processing, the wavelet softthreshold filtering of the swing CO2 welding voltage signal under the arc discharge sense was carried out, showing the possibility of removing the peak current of the shortcircuit transition and improving the signal-to-noise ratio.

二是利用小波分析在信号处理上良好时域、频域局域性，对电弧传感方式下的摆动焊接电流进行了软阈值滤波，取得了良好的效果，消除了短路过渡所造成的峰值电流，提高了信噪比。

It has been proved that Reichardt's Elementary Motion Detector can perform figure-ground discrimination efficiently, and Wavelet transform analysis is similar to the multi-frequency channel of human vision. So we combine EMD, Wavelet transform and Pyramid image processing together, to propose a new motion estimation algorithm. The computer simulation results reveal that the proposed algorithm can well simulate vistual motion evaluation.

本文利用Reichardt的相关型初级运动检测器二维阵列可以有效地进行图象－背景相对运动分辨的特点，以及小波变换的频谱分析特性与人类视觉多频率通道特性相类似的性质，将EMD模型、小波变换和图象的塔式结构处理有机地结合起来，提出了一种类似视觉信息加工方式的新的运动分析算法。

Using fluid dynamics FEM (two dimensional, three dimensional andaxisymmetric) and three dimensional acoustic FEM in meticulous analysis ofexpansion muffler structure, this paper studies the influences of each mufflercomponents' position, dimension, form and quantity on the fluid dynamic andacoustic performances;therefore the paper indicates that the end of the intruding tubeis the linchpin of the fluid dynamic performance of the whole muffler structure, thespringhead of muffler fluid dynamic performance is the smoothness of air current, themain factor which affects the acoustic attenuation value of expansion chamber muffleris the grade of saltation of the section of air conducting access, and the attenuationvalue of specific frequency can be dramatically enhanced by carefully designing thelength of expansion chamber.

本文通过流体力学有限元方法和三维声学有限元方法对扩张腔消声结构的参数化模型进行了细致的分析，研究了这种结构的各个组成部份的位置、大小、形状和数量对其流体力学与声学性能的影响，指出插入管端口是影响整个结构流体力学性能的关键，消声结构流体力学性能的根源是气流通过时的平稳程度；影响扩张腔消声量的主要因素为声波传播通路截面突变的程度，并可以通过精细的设计扩张腔轴向长度获得宽频或指定频率消声量的大幅度提高。

ABSTRACT The diffused phase transition and frequency dispersion of Pb-based complex perovskite relaxor ferroelectrics of PZN, PMN etc. were studied by the measurements of spectum of dielectric permittivity with temperature at different frequencies as well as by the means of differential thermal analysis and ferroelectric hysteresis technique. It was found that there are various polarization relaxors which cause DPT characteristics.

本文利用介温谱的测量，差热分析和电滞回线对以PZN，PMN为代表的铅系复合钙钛矿型弛豫铁电体的相变弥散和频率色散性等弛豫特性进行了分析研究，对产生弛豫的根本原因提出了新的看法，认为这类材料的DPT特性并不是一种由成份及结构不均匀的统计分布所造成的&准&弛豫现象，而是由材料本身弛豫机制所致。

Objective To investigate the effects of interleukin-1 β converting enzyme gene on the biologic characteristics of ovarian cancer cells.

目的 探讨白细胞介素-1 β转换酶的表达，对卵巢癌细胞生物学特性的影响。

Campylobacter: This illness is the most commonly identified cause of diarrheal illness in the world.

弯曲：这种病是最常见的原因查明腹泻病，在世界上。