谱函数

First,the basic formulas solving the artificial earthquake wave compatible with object response spectra are established;the integration equations are translated into the algebraic equations by interpolation function.

首先，从单质点系在地震作用下的反应出发，直接推导了求解与目标反应谱拟合的人造地震动基本公式；随后，利用插值函数将积分方程变换为代数方程组，进而从反应谱的变分求得人造地震动的时域变分。

It is concluded by the comparison of the Power Spectrum Density Function estimated from design spectra that the spectral energies do not distribute uniformly within the frequency of engineering interest in Chinese codes. The remarkable spectral energies concentrate in the range of low and high frequency.

由各规范设计谱估计的功率谱密度函数的比较说明，我国某些抗震设计规范设计谱给出的设计地震动在工程感兴趣的频率范围内可能存在能量分布不均的问题，低频分量和高频分量与中等频率段相比相对显著。

With the method, tendency of measured value was analyzed, harmonic mode was checked by using autocorrelation function, the relation between spectrum parameters was analyzed and Fourier coefficient was calculated based on the theory of Fourier series. Finally, the significance of every period was tested and dominant period determined so as to establish the prediction model.

首先对实测序列进行趋势项分析；其次用自相关函数进行谐波模式检验；然后根据函数的傅立叶级数展开理论，分析谱参数之间的函数关系，计算傅氏系数；最后采用F分布检验法对周期进行显著性检验，确定主要周期，从而建立预报模型。

A convergence acceleration technique based on functional asymptotic expansion and Poisson's summation formula is developed to raise the calculation efficiency of waveguide dyadic Green's functions which are expanded in infinite series.

为此，作者提出"谱展开边界元法"，以求解波导外空间的并矢Green函数；引入边界元法以求解波导壁内折曲缝隙腔的并矢Green函数；并研究了无穷级数的逐级加速收敛变换，以解决波导中Green函数的计算问题。

In this paper,in residue class ring Z_m,the concept of the strict avalanche criterion of order k of m-valued logical functions is presented.

给出了剩余类环Zm上逻辑函数的k阶严格雪崩准则的概念，用概率方法证明了m值逻辑函数满足高阶严格雪崩准则时一定满足低阶严格雪崩准则，并借助Chrestenson谱给出了m值逻辑函数满足k阶严格雪崩准则的一个充分必要条件。

Iterative process of error-reduction algorithm is anlyzed, the phase-only object function is obtained when the amplitude of object function and the amplitude of its Fourier transformation are known, and the amplitude and phase of object function are retained as much as possible.

分析了采用错误减算法的迭代过程，在已知物波函数傅里叶谱的振幅和物波函数振幅的情况下恢复出纯相位的物波函数，最大限度地保留物波的振幅及相位信息。

First, the methods and procedures of general three orders nonlinear identification are summarized and the results are frequency functions described by basic and high order spectral density functions and frequency response functions.

得到的结果是用基本的和高阶的谱密度函数以及基本的和高阶的频率响应函数表示的频率函数。

After the brief retrospect of spectral methods applied to get the numerical solutions of partial differential equations, the Walsh spectral methods are extensively studied. A new method of designing the "derivate operator" and a new Walsh spectral method based on quasi-Walsh order are proposed, which primarily prove the special uses of it.

回顾了数值求解偏微分方程的谱方法，比较深入地考察了数值求解偏微分方程的Walsh谱方法，提出了一种新的设计"求导算子"的方法，基于这样设计出来的"求导算子"，提出了一种新的基于类Walsh序的Walsh函数的Walsh谱方法，初步验证了这种序的特殊价值。

The numerical calculation commonly used for the Delphi process more than 100, including solutions of linear algebraic equations, interpolation, numerical integration, special, function approximation, eigenvalue problems, data fitting equation Root and solve nonlinear equations, functions and the extreme optimization, statistical data description, Fourier transform spectra, solution of ordinary differential equations reconciliation partial differential equations.

本书共有数值计算中常用的Delphi子过程100多个，内容包括解线性代数方程组、插值、数值积分、特殊函数、函数逼近、特征值问题、数据拟合、方程求根和非线性方程组求解、函数的极值和最优化、数据的统计描述、傅里叶变换谱方法、解常微分方程组和解偏微分方程组。

Comparison studies have been performed concerning of dynamic amplification factor β and power spectrum density function (approximately estimated from design spectra) between Eurocode 8 and primary seismic design codes of China.

用动力放大系数β对欧洲规范(Eurocode 8)和我国主要抗震设计规范的设计谱进行比较；并对由欧洲规范和我国主要抗震设计规范设计谱估计出的功率谱密度函数作了比较。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。