数值微分法

It is also shown for the first time that DQEM could be regarded as the combinations of the sub-domain method with the special mixed collocation method.

微分求积法和微分求积单元法是在近年里发展起来，并正在进一步发展的一种数值计算方法，本文对这两种方法的原理和它们在结构力学中的应用进行了较深入系统地研究。

The coefficients in trial function can be gained by the point collocation method, then the solution of the boundary value problems is obtained. Non - uniform beams and irregular plates on Winkler foundation and plates on elastic half space foundation can be numerical calculated by the introduced method.

为对土与结构物的相互作用进行研究，在采用适当的土体模型的基础上，必需求解地基与基础的共同作用方程，而该共同作用方程一般是偏微分方程或微分积分方程，除一些简单的模型外，其解析解较难获得，因此只能采用数值方法求其结果，加权残仇法是一种L作鼠少、简便易行的数仇方法{2，但其解的精度'。

The pressure correction method is used to calculate the two-dimensional turbulent flow in general curvilinear coordinates.

按照进气箱对称面的形状，给出一种简化的二维进气箱几何模型，用微分方程法生成贴体的曲线网格，在任意曲线坐标系下采用压力修正法数值模拟了其内部二维湍流流动。

On the whole, we do as follows: Firstly, we list some conceptions and lemmas for later use. Secondly, we define δ-fine partitions for infinite interval and integral of vector-valued functions on infinite interval, and discuss the properties of integral, and characterize its primitives...

主要包括以下五部分内容：在第一部分中，我们介绍了本文所用到的基本概念和引理；在第二部分中，通过定义无穷区间上δ-精细的分法，我们给出了无穷区间上向量值函数的积分的定义，并讨论其性质，还给出了原函数的刻划；在本文的第三部分中，我们着重讨论了无穷区间上向量值函数积分的收敛定理；在本文的在第四部分中，我们首先应用无穷区间上向量值函数积分的收敛定理给出了常微分方程整体广义解的存在性定理，其次应用强积分对Banach空间常微分方程广义解进行了讨论；最后，在第五部分中，我们将模糊积分推广到无穷区间上并给出了其数值计算方法。

In the method,thematrix exponential is calculated precisely by using 2N algorithm and the integration offunctional matrix by parts is applied.

首先依据常微分方程的经典理论，运用指数矩阵的2N类精细算法及函数矩阵的分部积分法建立数值求解常微分方程的一般方法。

On the basis of classical lamination theory and large deflection hypotheses of plate, the equilibrium and compatibility equations of simply supported composite laminated plates were obtained. The nonlinear partial differential equations are transformed into the ordinary differential equations of Kronecker tensor product by series expansion and solved numerically by the fourth-order Runge-Kutta method.

基於经典的层合板理论及板的大挠度基本假设，得到四边简支层合板的非线性运动方程及变形协调方程；用级数展开把非线性偏微分方程组化为易於求解的Kronecker张量积形式的二阶常微分方程组，并由四阶Runge-Kutta法数值求解。

Up to now, finite difference method, finite element method and boundary element method are common numerical methods to obtain numerical solutions of parabolic partial differential equation.

目前求解抛物型偏微分方程的数值方法有有限差分法、有限元法和边界元法等。

This paper considers the pricing model of options under illiquidity. A new numerical procedure for solving the nonlinear parabolic partial differential equation is explored and the Thomas algorithm is used to improving the efficiency of the numerical scheme.

本篇论文提出一个在市场流动性不足情况发生时的选择权订价模型，并且发展一个新的数值方法来求解一个非线性抛物线型态的偏微分方程式，同时利用汤马斯演算法来提升数值运算的效率。

In the method of numerical analysis, the spatial part of equation system in strong conservation form is first discretized by conventional central finite-difference approximation and then the system of partial differential equations becomes a system of ordinary difference equations.

本文所建数值方法的基本空间离散格式是中心差分，并用源于Jameson的标量耗散模型抑制数值波动；采用经典四阶龙格—库塔法积分经过空间离散后得到的常微分方程组当残差足够小时的解为稳态解。

According the experiential formulas of headbox to design the stepped diffuser headbox's geometry parameters. Supposing Paper suspension flow as potential flow and basing on hydrokinetic and computational fluid dynamics theories, we can solve the elliptoid partial differential equations which are followed by the flow functions and the potential functions by finite element method and simulate the flow's speed distribution with pde toolbox of matlab software. The simulate results and the flow analysis have good precision.

按照流浆箱的经验设计公式，设计阶梯扩散式流浆箱的各组件几何参数，以流体动力学、计算流体力学等理论为基础，假定浆流的流动为势流，采用有限元法求解浆流流动时其流函数和速度势函数所符合的椭圆型偏微分方程，应用matlab软件的偏微分方程工具包pde toolbox，模拟出所设计的流浆箱各组件内的浆流的流场流速分布，模拟结果与数值计算流动分析结果吻合。

For a big chunk of credit-card losses; the number of filings (and thus charge-off rates) would be rising again, whether

年美国个人破产法的一个改动使得破产登记急速下降，而后引起了信用卡大规模的亏损。

Eph. 4:23 And that you be renewed in the spirit of your mind

弗四23 而在你们心思的灵里得以更新