近似方法

The application of high order spectral analysis is related to computations of high order moment functions and multi-dimensional Fourier transforms. The errors appear in these computations and limitation of measured data may cause the failure of such comparison.

高阶谱分析方法的应用中要涉及到高阶谱矩、高阶相关函数及高维傅立叶变换的计算，这些计算所带来的近似及试验记录的局限性很可能是导致两种方法比较时不成功的原因。

For the diffusion coefficients of electrolytes in aqueous solution by the mean spherical approximation was modified in two ways.

采用两种方法对Barnard等的用平均球近似理论计算电解质在水溶液中的扩散系数的方法进行了改进。

First of all, we use approximate method of the super-symmetric quantum mechanics to calculate super-potential and eigenvalues of spheroidal functions in the first several terms. Further more , we derive the ground eigenfunction in the first order terms, which is very useful for applying of the spheroidal wave function probably

首先我们使用近似的超对称量子力学方法计算出前几阶超势和广义椭球函数的本征值；接着根据之前所求得的超势和本征值推导出广义椭球函数一阶基态波函数，该超对称量子力学方法的引入及一阶基态波函数形式将有利于广义椭球函数深入研究

Recently, there are some methods are utilized to study it, such as the modified Lindstedt-Poincare method, frequency-incremental method, stroboscopic method etc.

目前主要的近似求解方法有改进L-P方法、频率增量法、改进的谐波平衡法、频闪法等等。

By introducing the nonlinear complementarity problem function, the Karush-Kuhn-Tucker conditions of OPF model are transformed equivalently into a set of semismooth nonlinear algebraic equations. Then the set of semismooth equations can be solved by a semismooth L-M method based on the subdifferential. The method belongs to Newton-type method. It can ensure the positive defmitiveness of the iterative coefficient matrix by using the L-M parameter, which avoids the ill-conditioning of iterative equations. The method, requiring only the approximate solution of a linear system at each iteration, is quite applicable to the large-scale cases.

在利用非线性互补函数将OPF模型的KKT条件转化为半光滑非线性代数方程组后，采用基于次微分的半光滑L-M法求解，该方法属于牛顿法范畴，可通过对L-M参数的调整保证迭代系数矩阵的正定性，克服了系数矩阵的奇异引起的"病态"，且该方法在确定搜索方向时只需求解线性系统的加热器近似解，适用于大规模系统的求解。

Rolling force and moment are the basic technics parameter for Assel rolling mill design,but about it,s technics calculate is very poor currently.one form by dint of approximately calculate, the result unlikelihood .J·kazanecki and domestic scholar according as metal distortion superior limit,gave some formula have some worthiness,but very complexity.the author base on practicality rolling technics, gvie a simpleness calculate means.the result close to measure numerical value,supply some reference value.

轧制力、轧制力矩是设计Assel轧管机最为基本的参数，但是目前关于其工艺计算的理论还很不成熟，只能借助于近似工程计算方法求得，结果往往偏差较大。德国的J·kazanecki和国内的一些学者提出了利用金属塑性变形场的上界法求解上述参数，具有一定的参考价值，但其数学计算相当繁杂。作者从轧制工艺实际出发，遵循塑性力学的基本原理，给出了简便易行的计算方法，具有重要的实际意义。

The book covers one-, two- and three dimensional problems which are solved by using exact and approximate analytical methods and numerical methods such as: the finite difference method, the finite volume method, the finite element method and the boundary method.

书中涵盖一，二和三是利用精确和近似分析方法和数值方法，如：有限差分法求解二维问题，有限体积法，有限元法和边界法。

The voltage drops on two terminals and the total self-impedances of the feeder remain unvaried before and after using the T-BVDM.

文中给出了一些算例，并与严格潮流计算方法进行了比较，结果表明提出的简化方法的近似精度高，并且在应用到基于遗传算法和模拟退火算法等随机优化算法的配电网络重构时，可大大提高潮流计算效率。

In order to make use of time-frequency characteristic of signal,a new method of variational estimation on signal frequency by using AR model power spectrum estimation,designing band-pass filter to gain approximatively source signals and underdetermined mixed matrix,and constructing completed observation signals by expanded subspace primer vector is proposed.

充分利用信号的时频特性，提出了AR模型功率谱估计法滑动估计信号频率，设计带通滤波器近似获取源信号和欠定混合矩阵，以及扩展子空间向量基构造完备观测信号的方法，将问题转化为完备情况下的盲分离，最后运用FastICA方法实现了信号盲分离。

It is different from the finite element method which uses the calculus of variation to construct the element-based approximate equilibrium equation. It does consider the equilibriums of forces on the inter-element boundary, which are neglected in the finite element method through the weak formulation.

这种方法跟有限元素法不同，因为有限元素法是采用变分法建立各个元素的近似平衡方程式，这种方法也考虑元素与元素相连接的边界上的力平衡条件，而在有限元素法的推导过程中我们忽略了这种条件。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。