定积分

The basic idea is to set a continuous solution of the region with a finite number of discrete points instead of a grid consisting of, these discrete points called grid nodes the solution of a continuous area on a given function of continuous variables used in the definition of discrete grid variable function approximation the original equation and boundary conditions in the micro-business operators to approximate differential, integral with the points and to approximate, so the original differential equations and boundary conditions are replaced by algebraic equations near Side, that is, finite difference equations , solve this equation group can get the original problem in discrete points on the approximate solution.

基本思想是把连续的定解区域用有限个离散点构成的网格来代替，这些离散点称作网格的节点；把连续定解区域上的连续变量的函数用在网格上定义的离散变量函数来近似；把原方程和定解条件中的微商用差商来近似，积分用积分和来近似，于是原微分方程和定解条件就近似地代之以代数方程组，即有限差分方程组，解此方程组就可以得到原问题在离散点上的近似解。

By analyzing the bode diagram of HAPF system and minimizing the capacity of HAPF, the paper presents a frequency dividing control method based on fuzzy-PI. In this mean generalized integrator is used for frequency dividing integral and fuzzy arithmetic is for adjusting PI coefficients timely. Compare with other kinds of control methods, the proposed one is more simple and easier realization.

该文由常用的并联型HAPF的结构特点分析出发，从容量和幅频特性2个方面探讨HAPF控制中进行有效分频的必要性，根据HAPF对控制方法的要求，文章提出一种基于广义积分的模糊自整定PI控制方法，即通过广义积分实施对周期量的分频积分，同时由模糊算法进行比例和积分系数的在线调整，从而有效实现对HAPF的分频控制。

In the computation of aerodynamic forces, the present work is based on the work of Morino et al., but the following aspects are improved:(1) In computing the steady transonic aerodynamic load, the steady transonic nonlinear integral equation is solved by relaxation-iteration method in this thesis, instead of solving the time dependent transonic nonlinear integral equation, so that the computing time is saved greatly;(2) The influence coeifficients represented by volume integral are transformed to surface integral by using the Gaussian Theorem, so the analytical form of these coeifficients can be obtained and this leads to be more convenient to analyse and compile computer program;(3) The shock capturing method is used in every time step in present work, no shock moving term is added in the integral equation, so that it is more convenient and simpler to treat.

在气动力计算方面，本文基于Morino等人的工作，作了如下几方面的改进：（1）在计算定常跨音速流场（作为非定常绕流计算的初场）时，本文采用松驰迭代法直接求解跨音速定常非线性积分方程，而不是采用时间相关法求解非定常非线性积分方程，这样大大节省了计算机时；（2）将以体积分形式出现的影响系数化为面积分，并获得解析公式，这样便于分析和编写程序；（3）对运动的激波，本文通过在每一个时间步长上采用激波捕捉法而得到，而不是在积分方程中附加激波运动项，因而处理起来简单方便得多。

Since the stresses and strains at all sample points over the loading history are computed independently, the propagation of cumulative errors at the system stage is reduced in essence.

在单元特性分析阶段，新算法将在荷载空间内同时确定广义应力及广义应变的双变量问题变为对已知的广义应力自变量进行定积分的单变量问题。

From teaching experience of long term,in a new way,author put forward to a brand new succinct comment and certification of Riemann Integral.

在传统的定积分教学中，往往采用达布上和、下和方法来证明函数可积性，过程繁琐，难于理解。

In this method the self-adjusting integrator is adopted together with basic fuzzy control, according to the fuzzy control rule and practical experience.

该方法根据模糊控制规则和实际工程经验，在基本模糊控制的基础上增加了一个系数自整定积分器。

The arithmetic advanced people who had studied all knows , the integral concept is four key: Carve up similar summation taking a limit.

学习过高等算术的人都知道，定积分的概念是四个关键：分割——近似——求和——取极限。

The exact value of point coordinates on the easement curve can easily be obtained through using the definite integral function of Casio calculator.

利用编程计算器的定积分功能，就可以方便地计算出缓和曲线上点位坐标的精确数值。

However,some kinds of special type of definite integrals are difficult to calculate.

但几种特殊类型的定积分的计算却是难点。

Solveing to some extent problem to define hidden layer node number of feed forward networks,and makeing successfully it to apply to solve weierstrass theorem of that is polynomial approach continuous function;and establishing dynamic mathematical neural networks of Romberg integration.

从而在一定程度上解决了前向神经网络隐层结点数无法确定的难题，并成功地将其运用于解决用多项式逼近连续函数的魏尔斯特拉斯定理，并建立了龙贝格求定积分的动态数学神经网络模型。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了