查询词典 frequency analysis

The principle of MUSIC algorithm and theoretical analysis of the spectral separate frequency and frequency detection threshold are included. MUSIC algorithm compared with FFT based algorithm for harmonic frequency estimation using matlab simulation platform .

给出了MUSIC算法的基本原理，对MUSIC算法的频谱分辨能力和频率检测门限进行了理论分析，在Matlab仿真平台下对MUSIC算法和FFT算法的频率估计性能进行了比较。

This paper introduces eight methods of tlme-frequency analysis, such as Hilbert transform, Hilbert-Huang transform, sine curve fitting, Ricker wavelet matching, short time Fourier transform, wavelet transform, S transform and Cohen methods, This paper explains the merits and defects of those methods from the time resolution, frequency resolution and the adaptive ability of multi-frequency signals.

本文介绍了Hilbert变换、Hilbert—Huang变换、正弦曲线拟合、雷克子波匹配、短时傅立叶变换、小波变换、S变换以及Cohen娄这八种方法，并从时间分辨率、频率分辨率，以及对多频率成份信号适应能力等各方面阐述了各种方法的优缺点，对其中的一些方法结合了理论记录进行了试算，进一步阐述了这些方法的长处和不足之处。

Finite element method is based on the actual ship models, a true reflection of the real ship distribution of the specific structure. This paper also uses empirical formula to calculate the inherent frequency of the catamaran; contrast them in the process of modeling the structural stiffness, and quality of the different treatments, as well as natural frequency calculated from the results of differences analyze the different and the reason between the finite method and the empirical formula method which used to calculate the inherent frequency of catamarans in the vibration analysis.

有限元方法是根据实际船型，较真实的反映了实船结构的具体分布特征；本文还采用经验公式对该船的固有频率进行了计算，对比它们在建模过程中对结构刚度、质量的不同处理，以及计算所得固有频率结果的差异，分析了在双体船振动特性分析中有限元法与经验公式法的结果略有差距及其原因。

Based on Wavelet Packet Analysis and Smoothed Pseudo Wigner-Ville Distribution, the experiment data is time-frequency analyzed. The experimental results indicate that the amplitude of the laser-induced acoustic waves increases with the laser energy; the frequency coverage is from 0 to 150 KHz, and in the meantime there is a peak located at about 25 KHz. In addition, the spectrum and the peak of frequency are basically stable in spite of the change of laser energy and target texture.

从基本的空泡动力学理论出发，推导了空泡各特征参量之间的关系，进而对空泡动力学模型进行了修正；采用有限差分法对空泡脉动进行数值模拟，得到了空泡脉动特性随液体粘性、空泡含气量、表面张力以及可压缩性的变化规律；实验上采用光偏转测试装置探测了激光空泡脉动以及空泡溃灭的细节过程，进而分析了液体粘性和作用激光能量对空泡脉动周期、泡半径及泡能等特征参数的影响。

By parameter(tower total height, shell thickness, meridional curvature) analysis of cooling-tower natural frequency, we find that, the basic natural frequency of cooling tower is sensitive to the top meridional curvature, an approximate formula is proposed based on the parameters, which can estimate the basic natural frequency of cooling tower.

通过对冷却塔自振频率的参数分析，如塔体整高、塔壳厚度、子午线曲率等，发现基础频率对上部子午线曲率较为敏感，并给出了用于估算大型双曲冷却塔基础频率的三参数公式。

Secondly, a series of computer programs have been developed and verified according to the deterministic chaos theory and algorithms. These programs are deterministic chaos qualitative analysis tools including phase plots and Poincare section analysis software packages; deterministic chaos quantitative analysis tools including the largest Lyapunov exponent, correlation dimension and Kolmogorov entropy analysis codes and classical analysis such as power spectrum, autocorrelation coefficient and Hurst analysis programs.

其次，根据确定性混沌分析技术主要内容的算法思想，自行开发了相图、Poincare截面等定性分析程序软件包；最大李雅普诺夫指数、关联维数和K熵等定量分析程序软件包以及非线性混沌预测程序软件包；同时，还开发了功率谱、自相关系数、Hurst指数等传统分析技术程序软件包；并运用三种典型的周期运动、混沌运动及随机运动时间序列数据，验证了开发的程序。

Abstract〕similar to regression analysis,cluster analysis,etc.,correlation analysis is also the basic work for information researches.canonical correlation analysis can be used to analyze the relationship between two groups of variables,and thus worth for using in information science.method of canonical correlation analysis was presented in present study.a java-based network algorithm of canonical correlation analysis was developed,which can be used to calculate the canonical correlation coefficients,canonical variable pairs,and statistical significance of canonical correlation coefficients.the algorithm may be run on java-compatible web browser.at the same time,paper publishing information and citation statistics in information science of china in past years were analyzed using the algorithm,and a number of conclusions were drawn.

摘 要〕与因果分析等一样，相关分析也是信息资料分析的基本工作。典范相关分析用于分析两组变量之间的关系，在情报信息的相关性分析方面有潜在的应用价值。本研究介绍了典范相关分析方法，给出了典范相关分析的java网络算法软件，可用于计算典范相关系数，典范变量对，以及典范相关系数的统计显著性。该软件可在兼容java的网络浏览器上运行。同时，用该算法对国内情报信息论文的发文和引文统计数据进行了分析，得到了一些结论。

The mainly contents include: the research design of statistical survey, survey methods, the statistical sorting and analysis of information (contingency table, correlation measurement, inferential statistics, regression analysis, variance analysis, cluster analysis, factor analysis, principal component analysis), the composing of investigation report and the appliance of SPSS.

课程对社会统计和社会调查研究方法进行全面的介绍，要求学生牢固掌握社会统计和社会调查的基本研究方法，能熟练运用社会统计和社会调查的方法和技术从事社会研究工作，对社会统计学的概念和术语有一般程度的掌握，能应用SPSS软件进行社会统计和调查工作。本课程主要内容包括：统计调查的研究设计、资料的调查方法、资料的整理与统计分析方法（列联表、相关关系测度、推断统计、回归分析、方差分析、聚类分析、因子分析、主成分分析等）、撰写调查报告、SPSS应用等。

This article examines the dairy industry in the light of the analysis frame of the industrial chain with industrial organization\'s SCP analysis model, the game theory analysis method, the value chain analysis method, the case analysis and the econometric analysis method and has carried on a systematically theoretical discussion of and the empirical analyses of five key links of the longitudinal dairying industry chain and their cooperation mechanisms.

本文把奶业纳入产业链的分析框架，运用产业组织的SCP分析范式、博弈论分析方法、价值链分析方法、案例分析和计量经济分析方法对乳业纵向产业链的五个主要环节及其协作链接方式进行了系统的理论探讨和实证分析。

D. Methods In this dissertation, I adopt many research methods. a. Combine criterion analysis with demonstration analysis The demonstration analysis is the base of criterion analysis. In the research on regulation policy, value judgment is indispensable. So, I combine criterion analysis with demonstration analysis in this dissertation. b. Combine theoretic model with experience research Game theory can combine the theoretic model with experience study very well.

静态分析与动态分析相结合不同国家的对比需要进行横断面的静态对比，而竞争发展与产业组织的演进则是动态的，需要二者结合起来，但还是要以动态分析法为主，因为产业组织理论发展至今，为了与现实情况更接近，对多人、多期、双向动态决策的动态分析已成为产业组织理论的主流。

Bob Eckert has been chairman and chief executive of Mattel for eight years.

美泰董事长兼首席执行官鲍勃·埃克尔特在任已8年。

The outlook for honors and disgraces carries on and surpasses the traditional outlook for honors and disgraces theoretically, and carries on and develops the theory of construction of socialist mora...

社会主义荣辱观的提出在理论上是对传统荣辱观的一次继承和超越，是对社会主义道德建设理论的继承和发展，在实践上有利于形成良好的社会风尚。