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 为了更好的帮助您理解掌握查询词或其译词在地道英语中的实际用法，我们为您准备了出自英文原文的大量英语例句，供您参考。 
It is shown that diffusants which take part in surface reactions of finite rate or are subject to reversible trapping within the solid have a frequency response characteristic of the process involved.


A composite method to determine the tapping coefficients along with the coefficients of the subfilter to approximate overall frequency response characteristic is proposed.


Theoretical studies have been made on the effective ionization rates of electrons and holes of the device, IV characteristic and the frequency response characteristic of the AlxGa1xAs/GaAs superlattice p+in+ structure.


Probe bandwidth refers to the frequency response characteristic of a probe and specifies the normal operating frequency range of the probe.


In contrast to this, phonograph preamp circuits not only scale the signal, they also impart a specific frequency response characteristic to it.

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 The problem of accurately measure the spectral characteristics of a seismic observational system is an important subject of investigation in seismology. At present, the usual method to measure and calculate is by separate sections. In this way, it requires not only a certain amount of instrumental work, but also neglects the mutual effect between the seismograph and the amplifier at their junction. As a result, neither can the phasecharacteristics be directly determined by experiment nor accurate... The problem of accurately measure the spectral characteristics of a seismic observational system is an important subject of investigation in seismology. At present, the usual method to measure and calculate is by separate sections. In this way, it requires not only a certain amount of instrumental work, but also neglects the mutual effect between the seismograph and the amplifier at their junction. As a result, neither can the phasecharacteristics be directly determined by experiment nor accurate amplitudefrequency characteristics be obtained.In this paper, a method has been proposed for the determination of the spectral characteristics of any seismic observational system by means of Fourier Transform. It is called the TSmethod. Two testing signals are used, a triangular and a step function pulse. If the dynamic response of the testing signals are known the spectral characteristics of the system under investigation can be found immediately.The approximate formula for the spectral characteristics can be expressed asandWhen the transient response of system to any arbitrary input is known, the TSmethod can also be used to determine the frequency response characteristics of a system.  如何精确地测定地震观测系统的频谱特性,是测震学中的一项重要课题。目前所用的分段测量和计算的方法,不仅需要一定的仪器设备,而且还忽略了机(拾震器)—电(放大装置)接口部分的相互作用和影响。因此,不能获得精确的幅频特性,也不能用实验直接得出相位特性。 本文通过傅里叶变换推导出计算与实测任何一种测震系统频谱特性的方法——TS方法,其中用三角波与阶跃函数作为测试信号。 如果对测试信号的动态响应已知,则所研究的系统频谱特性可立即求得。 频谱特性的近似计算公式可表示如下: 以及 当任意输人函数作用下,系统的响应函数已知时,也可用TS方法求得频谱特性。  The strain tidal data observed by a YRZ2 bcrehole strainmeter of capacitive displacement type at the Sheshan Station in Shanghai City wore processed by the method of venedikov harmonic analysis without and with correction of ocean tide loads respectively. Results showed that: 1) the love number l2 of several main semidiurnal tides was close to the result calculated on the basis of the GutenbergBullen earth model A. 2) The love number l2 of several diurnal tides was much smaller, than the one of semidiurnal... The strain tidal data observed by a YRZ2 bcrehole strainmeter of capacitive displacement type at the Sheshan Station in Shanghai City wore processed by the method of venedikov harmonic analysis without and with correction of ocean tide loads respectively. Results showed that: 1) the love number l2 of several main semidiurnal tides was close to the result calculated on the basis of the GutenbergBullen earth model A. 2) The love number l2 of several diurnal tides was much smaller, than the one of semidiurnal tides. This was probably caused by the frequency response characteristic of the whole measuring system and the coupling state ibetween the sensor and the rock stratum. 3) In Shanghai the strain effect of ocean tide loads approached the direct effect of tidegenerating force, and after correction of ocean tide loads the accuracy of calculation was distinctly improved.  对安装在上海佘山地震台的 YRZ2型压容式钻孔应变仪的观测资料分别进行了未经海潮改正和经过海潮改正的调和分析计算。结果表明:(1)各主要半日波的勒甫数 l_2与根据 GutenbergBullen 地球模型 A 计算而得到的结果接近;(2)各主要日波的勒甫数 l_2较半日波明显地小,这可能是传感器和井壁之间的耦合状况以及整个观测系统的频响特征所致;(3)在上海,海潮负荷引起的应变效应在数值上与起潮力直接引起的应变效应相当,经海潮改正后,计算结果的精度有显著提高。  This paper describes in detail the working principles, structure and frequency response characteristics of an eddy geophone.Based on the dynamic analysis of the vibrataon system with one freedom, this paper studies the method for evaluating the system's natural frequency and damping coefficient by using experimental amplitudefrequency characteristics curves and has derived some necessary formulas. It also gives an example of application to verify its reliability.The experimental analysis... This paper describes in detail the working principles, structure and frequency response characteristics of an eddy geophone.Based on the dynamic analysis of the vibrataon system with one freedom, this paper studies the method for evaluating the system's natural frequency and damping coefficient by using experimental amplitudefrequency characteristics curves and has derived some necessary formulas. It also gives an example of application to verify its reliability.The experimental analysis method for evaluating the natural frequency and damping used in this paper is simple, convenient and accurate, and can be applied in similiar systems.  本文介绍了涡流地震检波器的工作原理、结构及其频率响应特性——涡流检波器的输出特性在固有频率之上是按外界激励频率的平方递增。高频灵敏度随着激励频率的增加而增高有助于弥补高频信号通过地层传播时的急剧衰减,从而提高了地震勘探的分辨率。在固有频率之下,则加强了低频滤波作用。 本文还以对单自由度线性振动系统的动态分析为基础,研究了利用实验幅频特性曲线来求该系统的固有频率和阻尼系数的方法,推导出必要的计算公式。最后举出一个应用实例,并检验了这种方法的可信度。   << 更多相关文摘 
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