查询词典 dirichlet boundary condition

In the third part, we discuss a simple class of Sturm-Liouville problems with Dirichlet boundary condition in the first boundary condition and an affine function in the second one.

第三部分我们讨论了一类参数边界条件的Sturm-Liouville问题，其第一边界条件为Dirichlet条件，第二个边界条件为特征值参数的线性函数。

In this dissertation, the author discusses the numerical solution for the direct acoustic scattering problem with the Neumann boundary condition, and pays more attentions to discuss numerical recovering the shape of the obstacle region, which is the inverse problem of the direct acoustic scattering problem with the Dirichlet or impedance boundary condition.

本文重点研究了Neumann边界条价下的声波障碍散射正问题和Dirichlet、Impedance边界条件下的声波障碍散射区域反问题的数值计算方法，得到很好的理论结果和数值结果。

Sometimes the boundary and the boundary approximately equate, sometimes the boundary contains the ideal condition, but the boundary and the ideal condition not are a chapter of matter.

境与境界有时大致等同，境有时包含意境在内，但境界与意境并不就是一回事情。

However, the second associated Legendre function is too complicated to compute, so a simple and practical ellipsoidal harmonic series expansion is introduced, and the series solution and integral solution of the Dirichlet boundary value problem and the Neumann boundary value problem under ellipsoidal boundary are given.

鉴于展开式中第二类缔合勒让德函数的计算较为复杂，接着引入一种形式简单、实用的椭球谐级数展开，介绍了椭球界面下Dirichlet边值问题和Neumann边值问题的级数解和积分解。

In the view of pragmatic implement, the theoretical framework of our proposed condition for spatial boundaries indeed can be reduced to the hybrid formulation of nudging filter, radiation condition taking account of ambient forcing, together with Dirichlet kind of compatible boundary condition to the observations prescribed in data assimilation procedure.

我们提出的空间边界条件的算法构架事实上是在数据同化过程中综合运用了张弛滤波、考虑外部强迫的辐射边界条件以及与观测相容的狄里希利边界条件。

New boundary integral equations for the torsion problem of an isotropic bar with curvilinear cracks are derived by using integration by parts and other techniques to the traditional boundary integral formulations. And the boundary integral equations for the torsion problem of an anisotropic bar with curvilinear cracks are also derived by using the isotropicalized boundary element method. Then the anisotropic problem can be solved on the base of the boundary element method of isotropic problem.

然后用各向同性化方法，将各向异性材料裂纹柱体的扭转问题转化为各向同性材料的问题，在各向同性材料裂纹柱体扭转问题的新的边界积分方程的基础上，推导出了适用于各向异性材料裂纹柱体扭转问题的边界积分方程，然后按已推导出的各向同性问题的边界元法求解。

LBIE, based on the local boundary equation, adopts the traditional moving least squares approximation which depends on only the values of the nodes in the domain of the problem or along its boundary. The whole process of integration is carried on over a local domain or its local boundary centered at the node in question. The local boundary equation can be rewritten to represent the values of the unknown function at the point of interest, and the essential boundary conditions can be directly and easily enforced by using the Green formula and the characters of the Dirac function.

它以局部边界积分方程为基础，采用移动最小二乘近似函数，从而只需要分布在问题域内及其边界上的节点的信息值，无需划分单元；整个积分是在以节点为中心的局部域及其边界上实现，所以不需要背景积分网格；借助于格林公式及Dirac函数的性质，将局部边界积分方程转化为所考虑点的未知函数的边界积分表达式，便于直接施加本质边界条件。

According to the different orientations of domain walls with respect to the (100) observation plane of a foil, 90°domain boundaries may be divided into two kinds. one is thin lens or ring shaped a-a 90°domain boundary, and the domain wall lies on the {110} plane; Usually, most of these domain boundaries are uncharged; according to the extinction rules for the (011) domain walls, the displacement vector 〓 along 〓 can be dertermined, which is parallel to the line of intersection between the domain wall and the plane consisting of spontaneous polarization vectors on both sides of domain boundary; from selected area electon diffraction of crystals including domain boundary, we not only examine slight difference in the crystal parts on both sides of the domain boundary, but also obtain crystallographic relationship between them, that is, there exists a 180°rotation symmetry operator along a normal of domain wall. The other is Z or ring shaped a-c 90°domain boundary along {010} direction, and the displacement vector 〓 runs along 〓 direction.

根据界面相对于样品中(100)观测面取向的不同，90°畴可分为两类：一类为薄透镜片状或环状的a-a90°畴，其界面平行于{110}，多数不带电，由消光规律可确定其位移矢量平行于畴界面与自发极化所在平面的交迹，即，〓方向，而从包含畴界的选区电子衍射图可知，这种不带电的90°畴界两侧存在微小的取向差，其界面两侧的结晶学关系为以界面法线为二次轴的旋转关系；另一类为Z状或环状的a-c90°畴，其界面平行于[010]或[001]，相应的位移矢量为〓方向。

For the third boundary value problem under ellipsoidal boundary, firstly we simplify the form of the third boundary value problem. Then, the solution of the the third boundary value problem under ellipsoidal boundary is discussed in detail, along with its series solution, the integral expression is mainly studied.

对于椭球界面下的第三类边值问题，先简化其形式，然后详细讨论了椭球界面下简化形式的第三类边值问题的求解方法，在给出级数解的同时，主要研究了它的积分解的表达式。

Coordinate sequence method is made up of the instruct information of polygon boundary x, y coordinate. It is the easiest polygon vector encoding method. The file structure of this method is easy, but because of the polygon boundary has stored two times, it will produce data redundancy, moreover, short of neighbor threshold information; Tree index encoding method make all the boundary points digitizing, store the coordinate sequence, connect the point index to boundary line, and then connect the line index to other polygons, so as to the tree index structure has came into being. It eliminates neighbor polygons boundary data redundancy problems; Topology structure encoding method is a method which by setting up a complete topology relationship structure, resolve the neighbor threshold and island information process problem. However, it makes arithmetic more complicated and makes database bigger.

坐标序列法是由多边形边界的x，y坐标对集合及说明信息组成，是最简单的一种多边形矢量编码法，文件结构简单，但多边形边界被存储两次产生数据冗余，而且缺少邻域信息；树状索引编码法是将所有边界点进行数字化，顺序存储坐标对，由点索引与边界线号相联系，以线索引与各多边形相联系，形成树状索引结构，消除了相邻多边形边界数据冗余问题；拓扑结构编码法是通过建立一个完整的拓扑关系结构，彻底解决邻域和岛状信息处理问题的方法，但增加了算法的复杂性和数据库的大小。

Objective:To explore the feasibility of laparoscopy in diagnosing and treating of abdominal diseases.

目的：探讨腹腔镜用以诊断腹部外科疾病及选择治疗方案的可行性。

The lifetime of nylon 1010 and nylon 1010/POSS composites decreased with increasing temperature.

热重-红外联用分析表明尼龙1010在氮气气氛下的降解产物主要为小分子的低聚物，POSS并不改变尼龙1010降解产物的组成。