变分方程组

Those equations are dispersed in space by iso-parameter elementmethod and in time by using backward difference. A numerical simulator is established byFortran, the ideas of high part make the of structure program clear, maintain easy, calculationeffective.

在此基础上利用Fortran语言编制了有限元方法的油藏模拟器，采用等参元对渗流方程在空间上离散，采用向后差分在时间上离散，线性方程组的求解采用变带宽高斯消去法，该方法充分利用刚度矩阵呈条带状和其对称性的特点，大大减少了所需存储空间。

The distributed parameter model is changed into variable coefficient nonlinear stiff ordinary differential equations by central difference method.

运用中心差分法将分布参数形式的系统模型转换为一变系数非线性的刚性常微分方程组。

The paper consists of four chapters:In chaper 1, we introduce the background and signficance, research and actuality on oscillation of functional partial differential equations; we present research subject in this paper;In chaper 2, we discuss oscillatory property of systems of parabolic differential equations with delays and obtain necessary and sufficient conditions for the oscillation of their solutions; we show the difference between oscillatory property of systems of parabolic differential equations with delays and that of systems of partial differential equtions without delays; we explain the main results with examples;In chapter 3, we discuss oscillatory property of systems of functional parabolic differential equations of neutral type; we obtain some sufficient conditions for the oscillation or full oscillation of their solutions under some conditions; we explain the main results with examples;In chapter 4, we discuss oscillatory property of systems of functional hyperbolic differential equations of neutral type; we obtain sufficient conditions for the oscillation or full oscillation of their solutions under some conditions; we explain the main results with examples.

全文共分四章：第一章简要介绍了泛函偏微分方程的振动的背景和意义、对其研究的简单历史和现状，给出了本文的主要研究对象；第二章讨论了一类时滞抛物方程组解的振动性质，获得了判断其所有解振动的一个易于验证的充要条件；指出了这类具有时滞偏差变元的抛物方程组解的振动性质和不具有时滞偏差变元的抛物方程组解的振动性质的差异；并举例对主要结果进行阐明；第三章讨论了一类中立型抛物方程组解的振动性质，获得了在给定的条件下其所有解振动或全振动的若干充分条件；并举例对主要结果进行阐明；第四章讨论了一类中立型双曲方程组解的振动性质，获得了在给定的条件下其所有解振动或全振动的若干充分条件；并举例对主要结果进行阐明。

By the principle of penalt function, the irrotational fluid field is constrained, and author has proposed the Difference Method for distinguishing fluid vortex modes among the natural modes of coupled systems. Author has calculated the real frequencies with the extra deductive method, and discussed the influence of the numerical solution due to the irrotational constraint.

对于流体有限扰动时的非线性耦合系统的有限元分析作了一些探讨，给出了非线性系统的基本方程、变分原理及有限元方程，并具体地导出了三维几何非线性流体单元的切线刚度公式，采用增量形式的Newmark预报——校正逐步积分法计算系统的动力响应，由Newton-Raphson迭代法及其修正方法求解系统的非线性方程组，还列出了不平衡力余量检查和位移迭代增量检查等迭代收敛判断准则。

The basic equations of structure are derived from Hamilton variational principle and the constitution of material utilizes the increment theory.

基于Hamilton变分原理导出圆柱壳的运动方程，本构关系采用增量理论，借助增量数值算法求解动力方程组。

The problem of solving linear equations changed equivalently into the problem of searching the minimum of unconstrained optimizations of function by variation principle in the paper.

首先通过变分原理将求解线性方程组的问题转化为等价的求解无约束函数最优化问题的极小值。

Based on the Galerkin Method the variational problem for the point source 2.5-dimensional electricfield is derived and the corresponding finite element equations are obtained.

基于Galerkin法推导了点源2.5维电场的变分问题，得到了对应的有限元方程组。

The nonlinear hyperbolic conservation laws of the transient flow of the media in gas pipeline are hard to he solved, so, the control conservation laws are constituted of mass, momentum arid energy conservation laws, TVD/Godunov hydrid algorithm is used to simulate the transient flow in gas pipeline, and the traditional splitting approach processing nonlinear convection in momentum equation is dismissed ,the convection tern; is directly processed, in the way, the stablization of the algorithm and emulating accuracy of the transient flow are greatly improved.

针对管道中介质瞬变流动的非线性偏微分方程组难以解析求解的问题，由质量、动量、能量三个偏微分方程构成的控制方程组，应用TVD/Godunov混合算法数值模拟天然气管道中气体的瞬变流动，摒弃了传统的差分方法时动量方程非线性时流项的线性化处理，而直接处理非线性对流项，从而大大提高了算法的稳定性和管道瞬变流动的仿真精度。

The optical soliton propagation in monomode optical fibres with third-order dispersion is reinvestigated by using variational method. The evolution equations for optical soliton parameters are found, and self-wave-peak shift phenomena is explained quantitatively.

用变分法重新研究了单模光纤中的三阶色散对光孤子传输的影响，找到了光孤子参数的演化方程组，定量地解释了光孤子的自波峰漂移现象。

By Ricceri's three critical points theorem, the existence of solutions for a class of quasilinear elliptic systems with variational structure was proved and the location of the solutions was also determined.

通过运用Ricceri的一个三临界点定理，讨论了一类具变分结构的拟线性椭圆方程组，获得了多解的存在性，并且给出了解的位置。

I will endeavour to find you some assistance.

我尽力帮你找人帮忙。

At first I only know bruck is the idol of American younglings, afterwards I returned back to Taiwan ,even in Beijing last year ,I saw her poster everywhere, I was so surprised at her charm.

起初我只晓得布鲁克雷德丝是美国少男少女崇拜的偶像，后来回台湾，甚至去年在北京，居然也四处看见她的海报，才惊讶她的魅力之大。