查询词典 difference boundary value problem

From proposing the problem to solving them, this thesis follows the researching method of from generality to specialty, also puts the mathematic knowledge of boundary value problem and the singular integral equation into the use of elastic mechanics and fracture mechanics, which shows the thought of combining the theory with the practical use. Throughout the thesis, the tendency that different branch of science is in fusion and penetration can also be found.

本文从提出问题到解决问题遵循由一般到特殊的研究方法，把边值问题和奇异积分方程等数学知识应用到断裂力学，弹性力学中，体现了理论联系实际及边缘学科间相互渗透的思想。

This paper was concerned with the Dirichlet-Neumann mixed boundary value problem of bipolar quantum hydrodynamic model in thermal equilibrium. By truncation method and Leray-Schauder fixed point theorem, the existence of solution to the problem is proved. In addition, the uniqueness of the solution was proved as the Plank constant was large enough.

研究了热平衡状态下双极量子流体动力学模型的Dirichlet-Neumann混合边值问题，利用截断方法和Leray-Schauder不动点定理证明了其解的存在性，另外还证明了当普朗克常数充分大时其解是唯一的。

In the study of the first problem, by using the fixed-point index theorems, we get the existence of boundary value problem in neither superlinear nor sublinear condition.

在第二种形式边值问题的研究中，主要利用Krasnoselskii不动点定理，得到了一些正解存在性定理及正解不存在性定理。

In this dissertation, we study the initial-boundary-value problem of modified Korteweg-de Vries equation and use the tool of harmonic analysis to study the Cauchy problem of Davey-Stewarson equation.

本文研究了modified Korteweg-de Vries方程初边值问题并用调和分析作为工具研究了Davey-Stewartson方程柯西问题。

On the basis of analyzing detailedly the correlative conclusions of the extreme value problem of two variable Function , this paper extends the essential condition and sufficient condition to multi-variable function by using the Taylor Formula 、Quadratic Form 、Hesse Matrix and so on,and gives a method to judge the extreme value of point whose vice-derivative doesn't exist by utilizing Lagranges theorem ,so that compensates for the blank above ,which turns idea that solve the extreme value of multi-variable function problem one by one into realities.

摘要本文在对二元函数极值问题的相关结论进行分析的基础上，用泰勒公式、二次型、海赛矩阵作为工具，将二元函数极值的必要条件和充分条件推广到多元函数的情形，而且还利用拉格朗日中值定理找到了一个判别不可导点处极值的方法，从而弥补了多元函数不可导点处极值无法判断的空缺。因而，使得用穷举判断的方法来解决多元函数的极值问题这一思路成为现实。

The problem of multi-objective usually meet many conflict each other and can not use the objective of the same standard unit, then to employ membership function of fuzzy theory,at first each objective function to change fuzzy set and express with membership function, membership function include the maximum constraint, minimum constraint, the decrease function of monotonic property, to become optimal of the multi-objective function, but still to scanty of weighting value with regard to adjustment of objective function, thus this thesis proposes the method of combine orthogonal arrays and particle swarm optimization to solve the problem of multi-objective optimal power flow, each objective function separately add weighting value, to setting each weighting value of objective function in order to the result of anticipating.

多目标最佳化的问题通常会面临到许多互相冲突且不能用同ㄧ标准单位的目标，於是利用模糊理论中的归属函数，首先将各目标函数转换成模糊集合并以归属函数表示，归属函数包含了最大限制值、最小限制值、单调的递减函数所组成，将各目标函数利用归属函数表示，形成单一目标函数的最佳化，但是仍缺乏权重值对於目标函数的调整，於是本篇论文提出ㄧ种权重值设定与粒子群优演算法的方法去解决多目标最佳电力潮流的问题，将各目标函上分别加上权重值设定各目标函数的权重值，得到预期的效果。

As for mixed problem with integral boundary conditions for a certain nonlinear pseudo-parabolic partial equation, the existence and uniqueness of a strong solution to the corresponding linear problem is established and so the nonlinear problem can be solved by using addition theorem.

对于一类非线性伪抛物型方程的带积分边值条件的混合问题，本文通过相应的线性方程利用迭加原理来解决。

Image segmentation based on the graph concept is analyzed in our thesis, a boundary finding problem is formulated as a shortest-path problem in a graph, then a watershed algorithm based ort image foresting transfonn is introduced, which is a unified and efficient approach for simplifying image processing problems to a minimum-cost path forest problem .

将图的概念应用于图像分割的研究中，把边界发现问题归结为图中的最短路径问题，从而引入了一种基于图像森林化变换(Image Foresting Transform，该方法是把图像处理问题简化为在图中求解最短路径森林问题的一种统一有效的方法)的分水岭算法，并分析了平滑滤波、梯度阈值在图像分割中的作用。

This thesis studied a kind of free- boundary problem that is abstracted from the model of tumor growth, and this problem is called quasi- steady problem.

本文研究了动物体内肿瘤生长过程中所提出的一类自由边界问题——拟稳态自由边界问题。

As same as the above-mentioned reason, because theconditions at the inside straight boundary of the binarycomposite material can not be easily satisfied, here, anelastic circular inclusion with large radius is used to replacethe upper half space of the binary composite material, so the〓mary binary composite mater ial problem can be changed〓the scattering problem of a circular elastic inclusion andto the scattering problem of a circular eastic inclusion and〓circular cavity in an infinite space to the steady incident〓wave.

与前面两个问题的理由一样，同样，由于问题中双质复合材料的内部直边界上的边界条件不易解析满足，为此，本文采用了一个半径很大的弹性实夹杂来代替问题中双质复合材料的上半空间部分，而将原来的双质复合材料问题转化成了无限大空间中一圆形弹性夹杂和一圆孔对稳态P波的共同散射问题，根据该问题的特点写出了弹性夹杂内外波场中波函数的一般形式解，利用该问题中夹杂和圆孔处的位移和应力的连续条件，并采用复数傅立叶级数展开技术将其化为一个仅包含问题波函数中未知系数的无穷线性代数方程组，在满足一定计算精度的前提下，通过有限项截断进行近似求解，进而讨论了双质复合材料中圆孔边界处的动应力集中系数随不同入射角、圆孔的不同位置、以及入射波的不同无量纲波数的变化和分布情况。

Don not attempt to do something which you can not to do.

不要企图做那些办不到的事情。

The expression of CTGF and TNF-αweredetected by immunochemistry and the number of Clara Cells was calculated.

光镜下观察肺组织的病理变化，采用免疫组化染色观察肺组织中结缔组织生长因子和肿瘤坏死因子-α的表达和Clara细胞的数量。