变分方程

The brachistochrone of an electric ball in the electromechanical coupling field was investigated according to variational method,and the corresponding governing equation(Euler-Lagrange equation) was derived.

通过变分原理的方法研究力电耦合场中带电小球的最速降线问题，导出其轨迹控制方程，即Euler-Lagrange方程。

ABSTRACT In this thesis, using the methods of ODE and calculus of variations, we prove the existence of radial and non-radial solutions of some classes of quasilinear elliptic equations.

本文主要是用ODE方法和极小变分方法证明拟线性椭圆型方程径向解和非径向解的存在性，用先验估计方法证明拟线性抛物型方程整体解的不存在性，得到了一些关于拟线性方程的新结果。

Considering the characteristic of dynamic consolidation in soft soil, L'place transformation is carried out on the basis of relaxed resolution problem of dynamic consolidation in saturated soft soil proposed by Zienkiewicz. With calculus of variations as the principal theory, the function of dynamic consolidation equation is constructed, and further, dynamic consolidation equation in matrix forms is deducted.

本文针对软土地基上动力固结法的特点，在Zienkiewicz提出的饱和土体动力固结定解问题的基础上做拉氏变换，以变分原理为基本理论，构造动力固结方程的泛函，进一步推导得到动力固结方程的矩阵形式表达式。

It takesthe weighted average of the L2 norm of the difference of the observation and thesolution of the system and the L2 norm of the difference of conormal derivativeat the different sides of the interface for every subdomain as cost functional andthe smooth coefficients of the subproblem and the value of solution of the originalproblem at interface as identification parameters;Using the property of continu-ous functional defined on compact set,the existence of the optimal solution of theidentification problem is proved;The necessary conditions of optimality charac-terized by the system equation,the adjoit equation and the variational inequalitysimultaneously are given by introducing the conception ofdifferential andadjoit variable;An algorithm is devised and its flow graph is given.

其次，针对分片光滑动力系统的特征，结合正演过程的区域分解算法，建立了分片光滑系统的分解区域参数辨识模型，该模型以子区域上解的实测值与计算值之差的L2范数和界面两侧的通量差的L2范数的加权平均作目标泛函，各子问题的光滑系数及界面上真解的值为待辨识参量；利用紧致集上连续泛函的性质，证明了子区域上参数辨识问题最优辨识参量的存在性；引入微分的概念，借助伴随变量，给出了由系统方程，伴随方程和变分不等式共同表征的最优性必要条件；根据此必要条件设计了算法，给出了算法的程序框图。

Majority of the problems researched by them were confined to the difference equations with positive variable or constant coefficient.

但大部分讨论的都是确定方程中变系数为正、或常系数的差分方程问题。

Aimed to the differential equation in form of convolution and the functional presented by M. E. Gurtin, the matrix operator which includes the differential equation and the boundary condition is proved self-adjoint, furthermore a general variational principles in form of convolution and the preparation theorem are given and proved.

针对M.E.Gurtin提出的含卷积运算的抛物型偏微分方程及其对应的泛函，运用泛函势算子理论，从理论上证明了含卷积运算的抛物型偏微分方程及其边界条件所对应的矩阵算子有势，进而给出并证明了具有普适意义的含卷积运算的变分定理及预备定理。

Based on nonlinear integral equation,the inversion equation is derived by using the variational principle.

该方法基于非线性积分方程，利用变分方法来建立反演方程。

In this paper, a semilinear elliptic equation with critical Sobolev-Hardy exponents is studied, the existence of nontrival solutions for which is proved by the linking theorem in variational calculus.

该文研究了一类带有Sobolev-Hardy临界指数的半线性椭圆方程，运用变分理论中的环绕定理证明了方程非平凡解的存在性。

Based on the continuity equation of groundwater and the normal velocity formula of free surface, taking element e as a subdomain R in the seepage flow domain R, according to variation principle, the finite element equation of seepage field can be obtained.

由地下水的连续方程和自由面的法向流速公式，把单元e作为渗流求解区域R上的一个子域ΔR，根据变分原理，得到岩土体渗流场有限元方程。

According to axisymmetric unsteady heat conduction equation of orthogonal aniso tropic material and boundary conditions,the equilibrium equation of a system of finite elements is deduced with triangular element of high accuracy,and programs are designed.

根据均匀正交各向异性材料轴对称热传导方程及其边界条件，利用变分法及欧拉理论，选取 6 节点的高精度三角形单元类型，推导了一般轴对称非定常热传导有限元基本方程。并编制了相应的计算程序。

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。