查询词典 radio frequency

So the frequency of pulse drive mode amounts to the frequency of external signal, and the operate frequency of driver should be below the frequency of MOSFET.

本论文所涉及的工作对半导体激光器的广泛应用具有积极意义，它解决了半导体激光器应用中存在的关键问题。

To further understand and correctly master the notion of marginal spectrum in Hibert-huang transform, the linear property of marginal spectrum is demonstrated, an mistake to the notion of marginal spectrum in some documents is pointed out, and a new viewpoint about the essential difference between marginal spectrum and Fourier frequency spectrum is put forward by which the amplitude of Fourier frequency spectrum only represents the probability that a frequency objectively exists in a signal while the amplitude of marginal spectrum decides whether a frequency objectively exists in a signal.

为了深入理解和正确掌握希尔伯特－黄变换（Hilbert-Huang Transform，简称HHT）中的边际讲概念，证明了边际谱的线性性质，指出了文献中对边际谱概念的一种误解，提出了边际普与Fourier频谱之间本质区别的一种的新观点，即Fourier频谱的幅值只能反映频率在信号中实际存在的可能性大小，而边际谱的幅值则能真实反映频率在信号中是否存在。

This design paper introduced one kind based on the DSP chip entire numerical control single-phase frequency changer design, along with the frequency conversion velocity modulation technology unceasing development, the frequency changer application is more and more widespread, the frequency changer besides has the remarkable velocity modulation performance, but also has the remarkable energy conservation function, is the enterprise technological transformations and the

本设计论文介绍了一种基于DSP芯片的全数字控制单相变频器的设计，随着变频调速技术的不断发展，变频器的应用越来越广泛，变频器除了具有卓越的调速性能之外，还有显著的节能作用，是企业技术改造和产品更新换代的理想调速装置。

This design paper introduced one kind based on the DSP chip entire numerical control single-phase frequency changer design, along with the frequency conversion velocity modulation technology unceasing development, the frequency changer application is more and more widespread, the frequency changer besides has the remarkable velocity modulation performance, but also has the remarkable energy conservation function, is the enterprise technological transformations and the product renewal ideal speeder.

本设计论文介绍了一种基于DSP芯片的全数字控制单相变频器的设计，随着变频调速技术的不断发展，变频器的应用越来越广泛，变频器除了具有卓越的调速性能之外，还有显著的节能作用，是企业技术改造和产品更新换代的理想调速装置。

The paper introduces application of frequency speed control ler on high-voltage plunger pump from frequency control moter speed theory,frequency speed contrcller volume defined and model selection,controlling optimizing and frequency speed control ler's installation,using,keeping.

从变频调速原理、变频调速器容量确定及选型、控制方式优化及变频调速器的安装、使用、维护等方面入手，介绍了变频调速器在高压柱塞泵上的应用情况；并总结出了处理变频调速下电机发热的方法；最后，对变频调速器的优越性能及节能效果进行了分析计算。

In series capacitance,the low frequency is load resonance frequency.In parallel capacitance,the high frequency is load resonance frequency.

在串联电容时，负载谐振频率是两个频率中的较低的那个频率，而在并联电容时，负载谐振频率则是其中较高的那个频率。

The noise frequency modulation signal was particularly analyzed. The Fokker-Planck equation of noise frequency modulation was presented and the Motion-Group Fourier Transform was used by converting the partial differential equation into the variable coefficient homogenous linear differential equations. Then the solutions were given by using the peano-baker series. So the probability density function of noise frequency modulation in the filter was given. On the basis of the probability density function the stochastic resonance of noise frequency modulation signal is analyzed.

首先建立了噪声调频干扰信号通过脉冲压缩雷达中频滤波器后所满足的福克尔－普朗克方程，然后利用群移傅立叶变换（Motion-Group Fourier Transform，MGFT）将此偏微分方程化成了变系数齐次线性微分方程组，并利用Peano-Baker级数法给出了该方程组的解，最后得到了噪声调频干扰信号通过脉冲压缩雷达中频滤波器后的概率密度函数，在此基础上研究了噪声调频干扰信号造成的随机共振现象。

It was found that the pemeability of the dust core was almost a constant in the frequency range from 1KHz to 100KHz,and the quality factor Q of dust core increased with increasing frequency.It was also found that Q became higher at the frequency over 50KHz in comparison with that of permalloy in higher frequency.

结果表明，在测量的频率范围内(1KHz-100KHz)，该粉芯的磁导率几乎不随频率变化而变化；粉芯的品质因数Q随频率的增加而增加，在较高频率时有着比坡莫合金粉芯还要高的值，具有应用价值。

Chapter one is "Introduction". On the basis of summarizing the history of the study of the pictophonetic characters, we suppose some theoretical principle, such as the principle of the correspondence between the form and the meaning of the individual graph of Chinese characters, the principle of the total graphs of Chinese characters being a character-formation system, and the principle of the optimum development of the character -formation system in the history, and som analytic methods, such as the methods of structrue-function analysis, form-position analysis and meaning factor analysis, in the study of the pictophonetic characters. Chapter two is titled"General knwledge of the pictophonetic character." We discuss their origins, nature and some standards of distingnishing them, introduce the knowledge about the editions of SHUO WEN JIE ZI, analyse the functions of the modules of pictophonetic characters in detail, discuss concretely the function of phonetic graphs showing origins and pronunciations, the function of meaning graphs showing meanings and analogies, and the function of distinguishment when the two kinds of graphs are conbined. Chapter three is"The system of meaning graphs of Xiao Zhuan system."After we describe the structure of the meaning graph system, the relations between meaning graphs, the distributions of the function of meaning graphs showing meanings, and the frequency of all this kind of graphs, we get a table of all meaning graphs, a table of the frequency. Chapter four is"The system of phonetic graphs of Xiao Zhuan system."We describe the structure of the phonetic graph system, the relations between phonetic graphs, and between their function showing origins and their function showing pronunciations, and their frequency, then we get ageneral table of phonetic graphs and table of their frequency. Chapter five is "conclusion". We think that systematical methodology is useful in describing and analysing the formation system of Chinese characters. The methodology is adaptable in describing the formation system of modern Chinese characters as well as the historical character systems, adaptable in describing horizontally as well as comparing vertically. Only when we finish the systematical vertical compare on the base of systematical horizontal decription, could we know the true history of the system of Chinese characters, recover the rule of the system's development, and supply the theoretical supports for the scientifical arrangement of modern Chinese characters.

第一部分—绪论，在总结形声字研究历史状况的基础上，提出了研究形声系统的理论原则和分析方法，即汉字个体字符形义统一的思想，汉字字符集合构形系统的思想，汉字构形系统历史演变系统优化的思想等三项理论原则和结构功能分析法，形位分析法，义素分析法等三种分析方法，还扼要地介绍了具体的工作程序和论文的主要内容；第二部分—形声字概述，论述了形声字的来源、性质和鉴别标准，介绍了对《说文解字》正篆形声字说解中的传抄讹误，版本异文，说解错误校勘和考证的经过，详细分析了形声字构件的功能，具体讨论了声符的示源功能与示音功能，义符的示意功能与类化功能以及声符与义符组合中的相互区别功能；第三部分—小篆字系的义符系统，从义符系统的构成、义符间的相互关系，义符示意功能的分布及义符的构字频度等不同侧面，对义符系统进行了全面的描写，产生了义符总表、义符间意义关系总表和义符构字频度总表；第四部分—小篆字系形声字的声符系统，从声符系统的构成、声符间的相互关系，声符的示源功能与示音功能的关系以及声符的构字频度等不同侧面，对声符系统进行了全面描写，产生了声符总表和声符构字频度总表；第五部分—结束语，在全面测查小篆字系形声字的基础上，对研究汉字的方法和现代汉字发展方向的问题提出了一些看法，认为系统论的方法是描写和分析汉字构形系统行之有效的方法，系统论方法，不仅适用于历史上文字系统的描写，也适用于现代汉字构形系统的描写，不仅适用了断代描写，也适用于历史比较，只有在对汉字断代系统描写的基础上进行系统的历史比较，才能认清汉字系统历史演变的真相，揭示汉字系统发展的客观规律，为科学地整理现代汉字提供理论上的依据。

Based on the principle of PEC, surface cracks mainly affect the high frequency components and subsurface crack mainly affect the low frequency components, so the PEC signals can be analyzed in frequency domain, which can eliminate the influence of noises during measurement. A method of frequency spectrum separating point is proposed for flaw classification, which enhances the accuracy in classification of defects. The agreement between theory and experiment shows that the present method is valid and applicable.

通过对脉冲涡流的理论分析发现，表面裂纹主要影响脉冲频谱中的高频成分，而表面下裂纹主要影响脉冲频谱中的低频成分，因此可以将时域中易受噪声影响的脉冲涡流信号变换到频域分析，提出了"频谱分离点"的方法来对裂纹进行分类识别，提高了缺陷分类识别的正确率，理论分析和实验结果相一致，证明了该方法的正确性和有效性。

Listen,point and check your answers.

听，指出并且检查你的答案。

Warming needle is one of effective treatment methods for knee arthralgia aggravated by cold,and it is simple,safety,so it should be developed in clinical acupuncture and moxibustion extensively.

但以本院科针灸门诊在2005年1月—2006年6月期间共收治膝痛患者100余例，经过临床的诊断后，其中施以温针治疗的48例，疗效显著，报道如下。1临床资料本组病例48