近似积分

A general formula for computing the OTF of a defocused optical system is derived from the Kirchoff diffraction integration under an approximate condition which is weaker than the Fresnel condition.

本文从基尔霍夫衍射积分公式出发，在弱于菲涅耳条件的近似下，以高斯像面的像差量及系统的离焦量为参变量，导出了便于计算离焦光学系统的OTF的普遍算式。

First, in the composite hypothesis testing, circular dispersion error which is more practicable than horizontal and vertical error is used to discuss some problems of the dispersion of impact points; and the critical area of decision in the dispersion problem is analyzed; the specific expression of Bayesian risk is worked out, which ameliorates the method that only can get the approximate solution by calculating numerical integration.

由此，本文主要应用Bayes方法对以下几方面进行了探讨：首先，在复杂假设下，本文利用圆散布误差这一精度指标对落点散布鉴定问题进行研究，它比以往所用的纵、横向偏差精度指标更具现实意义；分析了此鉴定问题的决策临界区域；给出其Bayes风险的具体表达式，对用数值积分进行近似求解的方法进行了改进；在此基础上，通过极小化试验的风险确定最优试验数n，并讨论了决策中犯两类错误的概率，给出了验前信息的表示。

The relationship between transient response and shape design variables is highly non-linear, and the behavior of feasible domains is often not good, which may cause convergence difficulties. In order to improve convergence speed of iteration process, some algorithms the feasible domains adjusting, the adaptive move limit, the approximate line search and the approximate reanalysis, are adopted.

采用基于Newmark积分的直接求导法计算瞬态响应灵敏度，在序列二次规划算法中采用了可行域调整、近似—维搜索、自适应运动极限等改进技术，提高求解效率和收敛稳定性，以解决结构动态响应与设计变量的关系复杂、高度非线性，优化可行区域的性态不良等问题。

A method for the generation of Weierstrass fractal surface is presented,based on Helmholtz equation,with the Kirchhoff approximation,the calculus formula of light scattered field on the 1-D Weierstrass fractal suface is deduced.

采用Weierstrass分形函数模拟实际粗糙表面，从简谐光波满足的亥姆荷兹方程出发，利用基尔霍夫近似推导出一维Weierstrass分形粗糙表面的光散射场的积分公式，考虑遮蔽效应后数值计算并分析了表面散射光强的角分布特性。

According to the theory of first-order Born approximation,a Fourier Domain Optical Coherence Tomography model of single scattering infinite narrow beam is established,and the reason why it is hard to obtain the exact solution of integrated scattering equation is analyzed.

选择多层介质作为样品，根据波恩一阶近似理论建立了单次散射的无限细直光束频域OCT模型，并分析了散射积分方程很难得到精确解的原因。

Semi-classical Approximation; PVTN Properties via Configuration Integral from Intermolecular Effects; Grand Canonical Ensemble II - Examples

半经典近似；对分子间作用，作定积分而得的PVTN性质；巨正则效果II

Based on the Kirchhoff Approximation, the polarimetric scattered field is derived in Cartesian coordinate system by integration of three matrices mentioned above.

基于基尔霍夫近似，用过以上所讲的三个矩阵在笛卡尔坐标系下的积分得到极化散射场。

In the numerical calculations,the unknown density of dislocation is approximated with the product of fundamental function and Chebyshev polynomials.The calculations show the present method yields rapidly converging and high accurate numerical results.

在数值求解这组奇异积分方程中未知位错分布密度近似为基本密度函数与Chebyshev多项式之积，计算表明，本文方法的数值结果不但收效快而且精度高。

Classical Statistical Mechanics; Hamiltonian and Ideal Gases; Factoring the Partition Function with the Semi-classical Approximation; PVTN Properties via Configuration Integral from Intermolecular Effects; Grand Canonical Ensemble I

经典统计力学；Hamilton函数与理想气体；半经典近似微分函数因数；对分子间作用，作定积分而得的PVTN性质；巨正则效果I。

Trimming correction is a way of using the area integral or Simpson to calculate the volume correction value.

纵倾修正是根据船舶首尾吃水差采用面积积分或复合辛普生方法近似计算体积修正量。

Objective To investigate the effects of interleukin-1 β converting enzyme gene on the biologic characteristics of ovarian cancer cells.

目的 探讨白细胞介素-1 β转换酶的表达，对卵巢癌细胞生物学特性的影响。

Campylobacter: This illness is the most commonly identified cause of diarrheal illness in the world.

弯曲：这种病是最常见的原因查明腹泻病，在世界上。