变分方程

This article use the improved integral inequalities with the deviate variable and some skills of inequalities as well as related knowledge about second-order differential equation,to obtain the following results: the classification of limit point case or limit circle case and boundedness for second order differential or difference equation with deviative variable,discussed the classification for certain n-order differential equations,Criteria for the classification of second order differential equation with deviative variable.

本文利用推广的具有偏差变元的积分不等式，结合不等式的一些技巧以及常微分方程的相关知识对一类二阶具有偏差变元的微分方程及一类二阶差分方程极限圆型的分类问题作了相关的研究工作，并且讨论了一类n阶具有偏差变元的常微分方程解的平方可积性与有界性和一类二阶非线性具有偏差变元的微分方程解的有界性。

Rumjantsev used Hamilton's principle with Lagrange's multipliers to generate the dynamical equations of a rigid-fluid coupled system in 1954 and the dynamical equations and their dynamical boundary conditions of a fluid-elastic coupled system in 1969, where the fluid is incompressible and inviscid. In 1990, Liu used Jourdain's principle with Lagrange's multipliers to generate the dynamical equations of a rigidfluid coupled system, where the fluid is incompressible and viscid.

Rumjantsev利用带Lagrange乘子Hamilton变分原理于1954年建立了刚—流耦合系统的动力方程，于1969年建立了流—弹耦合系统的动力方程及其动力边界条件，其中所考虑的流体是不可压无粘液体；Liu利用带Lagrange乘子Jourdain变分原理于1990年建立了刚—流耦合系统的动力方程，其中所考虑的流体是不可压粘性液体。

The essence idea of restoration based on Total Variation is that translate the problem into minimum of energy functional with TV regularization, then the Partial Differential Equations are got from the principle of variation, finally after discretization the optimal resolution with the numerical methods is obtained.

基于整体变分的图像恢复概括的说就是把图像恢复问题形式化为带有整体变分正则化项的图像能量泛函极值问题，采用变分原理将其中的最小化问题转为所要求解的偏微分方程，即Euler-Lagrange方程，利用数字图像本身的离散特征使用适当的数值方法来求它的最优解，最后达到逼近原始图像的目的。

The following are the major work in this thesis which has been studied and still needs to be studied further in the future: 1 An improved adjoint variational method is developed, thus it can be applied to the LAGFD-WAM Wave Numerical Model for data assimilation; 2 A linear evolution equation of spectral perturbation is derived in order to analyze its increasing or decreasing mechanism.

本论文主要完成了以下几个方面的研究： 1）建立了推广形式的共轭变分同化方法，使之能够应用于LAGFD-WAM海浪数值模式； 2）导出了扰动谱线性演化方程，分析了扰动谱增长、衰减机制，考察了涌浪情况下扰动谱的持续时效问题及风浪情况下扰动的演变过程； 3）利用波谱共轭方程初步分析了同化模型中距离泛函的敏感性及敏感区域空间分布； 4）将推广的共轭变分方法应用于海浪谱能量平衡方程，建立了连续形式的海浪同化模型，特别是严格导出了风输入、破碎、底摩擦、波波非线性相互作用和波流相互作用各源函数的共轭源函数表示式； 5）分别进行了波谱层次上和有效波高层次上的同化试验，并对数值结果进行了分析。

Variational identity play a important role to prove nonexistence and get prior estimate of solution, In this thesis, we study following parts on the relationship of symmetry group of partial differential equations with variational structure and the variational identity.

变分恒等式在证明具有变分结构偏微分方程解的不存在性以及得到方程解的先验估计时有着非常重要的作用，本文研究了一些具有变分结构偏微分方程的对称群与其变分恒等式的关系。

On the base of other researcher, the *** from the basic equations of stable current field to derived the expressions of boundary problems under 3-D condition. Without considering the EM effect and using the generalized variation principle, we can get the corresponding variation equation. Thronging subdivide the 3-D model, interpolation, analysis, and general synthesis with the triangular prism element, we can carry out the simulation on frequency-domain IP\'s parameters under level and undulate topography.

在前人工作的基础上，在忽略电磁效应的情况下，从稳定电流场的基本方程出发，推导了三维区域满足的边值题目，用广义变分原理得到相应的变分题目，通过用三棱柱单元对大地模型进行剖分、插值、总体集成，最后解方程，得到每个节点上的复电位值，最后实现了水平和起伏地形等条件下的激电参数的数值模拟。2。

We show that the value function satisfies a free_boundary problem, prove the existence of the optimal policy by variational equation and get the optimal policy.

给出了价值函数满足的自由边界，用求解变分方程的方法证明了最优控制的存在性，并找到了最优控制策略。

Under the new boundary conditions related to viscous fluid, the variational equation of beam bundle fluid-solid coupling system related to viscous fluid is reached.

3在流体有粘的假设下，本文为随后的数值分析做了一些基础性的工作，在有粘流体相应的边界条件下，得到了粘性流体下管束流固耦合系统的变分方程。

At first, we give the more precisely expression of the system in some sufficiently small neighborhood of the saddle point under some suitable transformation, and use the foundational solutions of the linear variational equation of the unperturbed system along the homoclinic or heteroclinic orbits as the demanded local coordinate system.

首先，我们在鞍点的充分小邻域内给出系统在适当的变换下的更加精确的表达形式，利用未扰系统沿同宿，异宿环的线性变分方程的基本解组作为系统在同宿，异宿环的小管状邻域内的新的局部坐标系。

At the same time, variational equations, their finite element formulations and numerical convolved integration algorithm of the model in current configuration usually called co-moving coordinate system are given.

基于非线性几何场论，建立了材料非局部连续模型、变分方程及相应的实时拖带系大变形有限元数值模型，设计了这一模型的数值卷积算法。

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。