近似法

Experimental study on the properties of autocorrelation function of image speckles produced by weak random screens.

随机表面散射光场的格林函数法与基尔霍夫近似的比较。

For every step of arbitrary m-th order finite element methods of nonlinear Hamiltonian systems are first proved high accuracy conservate their symplectic structure, through construct a new auxiliary equation and negative norm estimated of error.

对非线性Hamilton系统的任意m次有限元法，构造了新的辅助问题，并得到误差估计和负范数估计，首次证明m次有限元对每一次步进是高精度Oh~(2m+1意义下近似保辛的。

Approximating unknown function by barycentric Lagrange interpolation which has advantages of higher precision and good numerical stability, the barycentric interpolation collocation method for analyzing deformation and buckling load of ring is presented.

采用数值稳定性好、计算精度高的重心Lagrange插值近似未知函数，提出数值分析圆环变形和临界载荷的重心插值配点法。

In Part I, the biharmonic equation are chosen, and the boundary peanlty finite method using piecewise cubic Hermite elements is used to seek their approximate solutions, in particular satisfying the derivative and periodical boundary conditions.

在第一部份里，选择使用片断三次 Hermite元素的边界惩型有限元素法来求解满足边界导数条件和边界周期条件的重调和方程式的近似解。

In this paper, based on variational principle and bilinear coordinate transformation, a spline Kantorovich method using cubic B-spline function is presented to obtain an approximate solution for the free vibration problem of arbitrary quadrilateral plates with various boundary conditions.

本文从变分原理和双线性坐标变换出发，采用基于三次B样条的康托洛维奇法得到了带有各种边界条件任意四边形板自由振动的近似解答。

Based on the process models and the desired closed-loop system responses, the analytical expressions of the tuning parameters of the primary and secondary controllers were proposed by means of first order Páde approximation, and then the digital PID controllers were obtained by using bilinear transformation method.

基于过程模型和期望闭环系统响应整定PID参数，采用一阶Páde近似纯迟延环节，以解析的形式推导出了主控制器和副控制器整定参数的表达式，并采用双线性变换法得到离散时间PID控制器。

Band structure, density of states, and optical properties of Zinc blende CdTe have been investigated using the plane-wave ultrasoft pseudopotential technique based on density functional theory.

采用基于密度泛函理论框架下广义梯度近似平面波超软赝势法，计算了闪锌矿型CdTe的能带结构、态密度和光学性质。

Electronic structure and optical properties of zinc blende CdSe have been investigated using the plane waves ultrasoft pseudopotential technique based on the density functional theory.

采用基于密度泛函理论框架下广义梯度近似平面波超软赝势法，计算了闪锌矿型CdSe的电子结构和光学性质。

Due to the restriction of computational complication and precision,WRM boundary collocation method can only be used to simulate temperature fields of single-particle model,as for the case of some more complicated particle geometry shape it is very hard to obtain sufficient approximation solutions.Thus,BEM is adopted to analyze the thermal conduction problem of composites with particle of arbitrary geometry.

由于受计算复杂程度和计算精度的限制，采用加权残值法只能分析单夹杂问题，且对于更复杂的夹杂形状很难得到良好的近似解，因此接下来采用边界元方法分析了具有任意形状夹杂复合材料的温度场问题。

The Computer-aided method also exploits the characteristic of linear differential equation with two additional approximations.

计算机辅助法也充分利用了线性微分方程的特点及另外两个合理的近似条件。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。