近似计算

In quasi-static conditions, the closed expressions far from source in the air and the earth is derived for electric dipole source, and by using it as the outer boundary conditions of the finite element method, difficulties in loading the boundary conditions is solved.

在准静态近似条件下，分别推导了水平电偶极子在空中和大地的远区电场闭合表达式，并以此作为有限元计算中的外边界条件，解决了边界条件加载的困难。

Based on the analysis of the necessary condition for OWT,using the cascade algorithm and 2D separable wavelet transform scheme,discrete approximation sequence of scaling and wavelet functions was computed for optical implementation.

通过对光学小波变换的必要条件进行分析，采用层叠算法和二维可分离小波变换构造方法计算出了尺度和小波函数的二维离散近似序列。

In this paper, the stray light and ghost image caused by multi-reflection in high power infrared optical systems are analyzed and discussed, and the comprehensive method incorporating paraxial approximation and real ray trace is presented; the data structure of binary tree is used in the storage of interdata so that the storage problem of huge-size data is resolved.

本文主要研究了大功率红外光学系统中光学表面多重反射而形成的杂散光及其数学模型与计算方法，提出了将近轴近似法和有限光线追迹法相结合的综合分析方法；同时在数据存储方式上采用二叉树这种数据结构，巧妙地解决了鬼像分析中海量的中间数据存储的问题。

The method is easily realized with small computation amount,and its absorption effect is better than conventional paraxial approximation absorption boundary condition.

该方法简单易行，计算量小，而吸收效果比常规旁轴近似吸收边界条件更好。

The optical matrix under paraxial approximation can make the calculation of optical transmission easy and convenient in designing optical system.

傍轴近似下的光学矩阵理论，可以简化光束传输计算过程，使光学系统设计更为方便。

The full parallax CGHs are generated by the point source method and the wave-oriented method without paraxial approximation.

这种全视差计算全息图是由点基元方法和平面波导向法生成并且没有经过旁轴近似。

The paper presents an efficient approximate algorithm for Convex Hull of very large planar point set.

提出了一种计算海量平面点集凸壳的快速近似算法——点集坐标旋转法。

We find, the optimal consumption is not clearly related to the hedgeable risk and unhedgeable risk which is different with precautious saving theory in macroeconomics.

我们提供了一个可以显式给出的近似解以及一套数值计算的方法。

The finite-difference method of calculation on primary wave traveltime based on any rectangular grid and a local plane wavefront approximation has high precision and can apply to complex media with violent velocity variation.

基于任意矩形网格和局部平面波前近似的有限差分初至波走时计算方法精度较高并适用于强纵横向变速的复杂介质。

Basing on the variation principle of solid-fluid coupled problem,on the situation of the tank being full filled,the essential method and principle have been found by using the numerical approximation of finite element method.

在罐车满载的情况下，根据固液耦合问题的广义变分原理，使用有限元的近似数值计算方法，找到解决满载罐车液固耦合振动问题的基本方法和原理，建立铁路罐车的固液耦合问题的动力学控制方程，并通过算例验证液体对罐车耦合振动的影响，得到在工程上所需要的分析结果。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。