查询词典 frequency analysis

This invention relates to three-dimensional seismic data processing quality monitoring technology. Selecting time-window and analysis frequency for FFT to obtain frequency-domain conversion result for every channel; taking mean-filter to obtain the statistic excited energy or noise disturbance; plotting all results on plane graph to monitor the 3D excited energy or noise disturbance; taking normalization and autocorrelation to all earthquake channel; summating all autocorrelation statistic result to obtain opposite statistic autocorrelation result; finding out and plotting the zero-crossing of autocorrelation on plane position for monitoring excited wavelet.

本发明涉及一种三维地震资料处理质量监控技术，步骤是：选定时窗和分析频率；对某炮各地震道在时窗内做快速富立叶变换，得到道数据在频率域变换结果；对同炮的所有地震道做频率域中值滤波，得到该炮的统计激发能量或噪声干扰量结果；将所有炮的计算结果绘到各炮点平面图上，监控三维激发能量或噪声干扰；对地震数据某炮的各地震道做归一化自相关；对同炮的所有地震道的自相关统计求和，得到该炮的统计自相关结果；寻找该炮统计自相关的零交叉时，将所有炮的零交叉时绘到各炮点平面位置上，完成激发子波监控。

In this paper,the stability of carrier frequency is used as the fine-grained characteristics of the individual communication transmitter based on the stability analysis.After that,the techniques of extracting frequency stability are well discussed,three approaches ...

该文重点研究了频率稳定度的有效提取技术，提出了3种有效的提取方法，在详细分析基本原理基础上，进行了仿真实验，比较精确地获取了载波频率稳定度信息，最后利用实际电台进行了验证，结果表明算法的有效性。

Vibration test of pole-shaped grain is conducted under various frequencies. The experiment results of acceleration frequency response is in agreement with theoretical data, which shows VFD model can also be used in SMR frequency domain analysis.

同时，杆状药柱在不同频率下简谐振动试验的加速度频响函数与VFD理论分析结果比较接近，说明这种模型也可以用于药柱的频域响应分析。

The principle and current loop dynamic response are analyzed for both constant frequency current mode control and newly presented quasi-constant frequency hysteresis PWM control, experiments have been carried out to proof the analysis.

文中对现有的固定频率电流模式控制方法和所提出的准固定频率PWM电流控制方法的原理和闭环响应进行了分析，并通过实验证实了分析的正确性。

Used mainly engaged in Communications equipment Products: Network Analyzer, integrated tester, spectrum analyzer, noise figure testers, receiver, telephone tester, high, low-frequency signal source, audio and video signal source, high, low-frequency oscilloscope, modulation device, video analysis detector.

主要经营二手通信仪器产品：网络分析仪，综合测试仪，频谱分析仪，噪声系数测试仪，接收机，电话测试仪，高、低频信号源，音、视频信号源，高、低频示波器，调制仪，视频分析仪等。

Based on the result of normalized frequency with effective refraction index -1 versus inner radius of ring-shaped holes we theoretically analysis the effects of structure parameters to equifrequency contours of respective normalized frequency and imaging properties.

通过光子晶体有效折射率的计算，得到了有效折射率为-1 的电磁波频率随空气环内径由0～0.2a 变化的规律，并由对应等频曲线的变化解释了结构参数对光子晶体平板成像的影响。

Based on these design guides, the analysis and design of a low phase noise and low power dissipation, with 0. 18μm CMOS process, integrated Colpitts crystal oscillator with automatic gain controlled feedback loop as the amplitude-limiting technique, low dropout voltage regulation with band gap reference voltage and frequency tuning monotonicity guaranteed by digitally controlled variable capacitor array is performed to revise influence caused by process, voltage and temperature conditions for. handset. The oscillation with very stable amplitude value and frequency value is achieved.

它利用对工作温度、电源电压和制造工艺不敏感的带隙基准源和在集成电路中元件特性之间匹配好的优点产生了一个不随温度、电源和工艺改变而且可以跟踪工艺变化的参考基准电压，同时通过自动频率控制环路利用数字电路控制可变电容阵列控制瞬态频率稳定度，校正温度、电源和工艺改变对频率的影响，从而可以在很宽的电源电压范围(2.7v—3.7v)和温度范围(-40℃—125℃)以及CMOS工艺参数变化(TT、FF、SS、SF、FS)的条件下提供幅度稳定、频率稳定的振荡输出信号。

Based on the time-frequency analysis (continuous wavelet transform and short time Fourier transform), the arithmetic uses the modulus maximum characteristic on the phase scale and carry frequency scale to recognize phase modulation rule of signal. So without whole wavelet coefficient the signal mathematics model can be obtained quickly. It provides well condition for application of arithmetic in practice.

该算法基于信号的时频分析（小波分析和短时傅里叶变换），利用小波变换的相位尺度和载波尺度的模极大值特征辨识信号的相位调制规律，因而在无需计算全部小波系数的情况下，可快速地获得信号的数学模型，为算法在实际中的应用提供了良好的条件。

Results When some alleles have very low frequency in the gene frequency matrix, there will be "horse-shoe effect" in the scallergram of correspondent analysis.

结果当基因频率矩阵中存在稀有基因时，其对应分析的散点图常呈现明显的&蹄型效应&。

Mainly, the article divides into six contents: system development background and method of exploitation, demand analysis, system analysis, system design, system implementation and conclusion. In demand analysis, has established first with the example model, and comes the detailed description through the active chart to use the example. Through the sequence chart and the VOPC chart, I completed the definition of boundary, control and data entity of the fore-platform in system analysis. The system design mainly has carried on the detailed design to kind of and the database.

在需求分析中，先建立了用例模型，通过文字和活动图来详细的描述用例，确定了前台子系统的各个功能模块；系统分析中，使用序列图和VOPC图完成了对系统运作过程中涉及的界面、控制、数据实体的定义；系统设计主要主要对类及数据库进行了详细的设计；系统实施中，对前台子系统的物理部署、实施环境进行描述，包括系统的主要界面和部分代码。

He got into race cars, while my father liked go-karts more, so I didn't really pay attention to what Diego was doing, as I was just racing karts.

叔叔开的是跑车，而我父亲更喜欢越野卡丁车，所以我并不太关注Diego在做什么，我仅仅在跑我的卡丁车而已。

She is at present gone to look for the best nectar and ambrosia to regale me this evening.

她今晚为款待我，现在又去准备美酒佳肴去了。