查询词典 exterior boundary problem

In the last chap-ter,the natural integral equation and natural boundary element method forharmonic problem on exterior elliptic domain are introduced.Then,based onthis,the natural boundary reduction method for a kind of exterior problem ofanisotropic constant coefficients elliptic equation is discussed, the natural inte-gral equation and its solving method on circular boundary and elliptic bound-ary are obtained.These results can be directly applied in coupled methodand DDM for exterior boundary value problem.

最后，讨论了椭圆外区域调和问题的自然积分算子即D-N算子及自然边界元方法，并基于此研究了一类各向异性常系数椭圆型方程外问题的自然边界归化方法，首次得到其在圆周边界及椭圆边界上的自然积分方程及其求解方法，并将这些结果直接应用于外边值问题的耦合算法。

Compared with the initial value problems of scalar conservation laws with smooth flux function, the global weak entropy solutions for the initial-boundary value problems of scalar conservation laws with weak discontinuous flux function include the following new interaction types: a rarefaction wave collides with the boundary and is absorbed compltetely or partially by the boundary; a rarefaction wave collides with the boundary and the boundary will reflect a contact or non-contact shock wave; a contact or non-contact shock wave collides with the boundary and is absorbed by the boundary; a contact or non-contact shock wave collides with the boundary and a new non-contact shock will rebound from the boundary simultaneously or later.

与具有光滑流函数的单个守恒律的初始值问题相比，具有弱间断流函数的单个守恒律初边值问题的整体弱熵解中包括下列新的相互作用类型：稀疏波碰到边界并被边界部分或全部吸收；稀疏波与边界相撞，边界反射出一个接触或非接触激波；接触或非接触激波碰到边界并被边界吸收；接触或非接触激波与边界相撞，边界同时或稍后反射出一个新的非接触激波。

The result shows that the mixed boundary condition can greatly reduce the calculation area without affecting accuracy of the solution.It is followed by the higher accuracy of Dirichlet boundary condition which makes the boundary error greater when measured points is near the boundary, so we must take a sufficiently large border region.The homogeneous boundary condition has relatively large error, but the use of non-triangle poles devices makes apparent resistivity calculation error become small, because of elimination of the effect on potential difference for the infinite boundary. In inversion, in order to save computing time, homogeneous boundary conditions are often used to perform finite element forward calculation.

结果表明，混合边界条件精度最高，可大大缩小求解区域而不影响计算精度，其次是Dirichlet边界条件精度较高，但测点越靠边界误差会越大，必须取足够大的边界区域，齐次边界条件的误差比较大，但如果采用非二极装置，通过电位差计算得到的视电阻率，由于无穷远边界对电位差的影响基本消除，视电阻率计算误差与混合边界条件下的接近，在反演中，为了节省计算时间，经常使用齐次边界条件进行有限元正演。

The boundary contour formulations of evaluatingstresses from the Somigliana stress identity are derived for 2-D problemswith quadratic boundary elements.The boundary contour method basedon the traction boundary integral equation is further discussed.Elasticproblems are first solved using the traction boundary contour method.Amixed collocation of the displacement boundary contour formulation andtraction boundary contour formulation is given.(4)The dual boundarycontour method is developed for the analysis of crack problems.

3建出了Somigliana应力积分式的二维和三维问题的边界轮廓法理论；给立了二维问题由Somigliana应力积分式计算应力的二次形函数的边界轮廓法方程，进而给出了基于面力边界积分方程的边界轮廓法；提出了一种以位移边界轮廓法方程与面力边界轮廓法方程混合配置的方案，首次实现了用两种积分方程相结合来求解弹性力学问题。

For the Riemann boundary value problems for the first order elliptic systems , we translates them to equivalent singular integral equations and proves the existence of the solution to the discussed problems under some assumptions by means of generalized analytic function theory , singular integral equation theory , contract principle or generaliezed contract principle ; For the Riemann-Hilbert boundary value problems for the first order elliptic systems , we proves the problems solvable under some assumptions by means of generalized analytic function theory , Cauchy integral formula , function theoretic approaches and fixed point theorem ; the boundary element method for the Riemann-Hilbert boundary value problems for the generalized analytic function , we obtains the boundary integral equations by means of the generalized Cauchy integral formula of the generalized analytic function , introducing Cauchy principal value integration , dispersing the boundary of the area , and we obtains the solution to the problems using the boundary conditions .

对于一阶椭圆型方程组的Riemann边值问题，是通过把它们转化为与原问题等价的奇异积分方程，利用广义解析函数理论、奇异积分方程理论、压缩原理或广义压缩原理，证明在某些假设条件下所讨论问题的解的存在性；对于一阶椭圆型方程组的Riemann-Hilbert边值问题，利用广义解析函数理论、Cauchy积分公式、函数论方法和不动点原理，证明在某些假设条件下所讨论问题的可解性；广义解析函数的Riemann-Hilbert边值问题的边界元方法是利用广义解析函数的广义Cauchy积分公式，引入Cauchy主值积分，通过对区域边界的离散化，得到边界积分方程，再利用边界条件得到问题的解。

For reducing boundary distortion area, the elevations of grid DEM are viewed as a discrete sequence under a generalized coordinate, so that the boundary problem of two-dimensional discrete wavelet transform is turned into the boundary problem of one-dimensional discrete wavelet transform, which not only greatly reduces the boundary distortion area, improves the precision of reconstructed DEM data near the boundary, but also decreases the number of zeros adding on the boundary for wavelet transform, and boosts the compression ratio. On the basis of analyzing the distribution characteristics of coefficients in low and high frequency bands, a mixed entropy coding plan is applied, and a high efficient quantizator called"self-adaptive hard threshold"is established, which is helpful for improving the precision of the reconstructed DEM data and for enhancing compression ratio.

为了减小小波变换山区格网DEM数据压缩中边界失真区域，将山区格网DEM高程值视为广义坐标下的离散随机序列，把二维离散小波变换中的边界问题转换为一维离散小波变换中的边界问题，不仅大大减少了小波变换边界失真区域，提高了重构DEM数据边界点的精度，而且减少了边界补零个数，提高了压缩比；通过对山区格网DEM数据小波变换低频区和高频区变换系数分布特点的分析，采取了霍夫曼—游程混合熵编码方案，设计了高效、低失真的"自适应硬阈值"量化器，即对低频区变换系数不进行量化，直接进行霍夫曼编码；对高频区变换系数则先用"自适应硬阈值"方法量化处理，再进行游程编码。

With the help of the fundamental theory to singular measure differential system, Green's function matrix expression of solution and well-posed boundary condition are given, together with discussing the properties of the Green's function matrix under the influence of impulsive effect In section 5, based on Lyapunov function method, we investigate that the existence of the first boundary value problem to second-order singular system by macthing the solutions to the second boundary value problem; and the existence and uniqueness of three-point boundary value problem to third order singular system by macthing the solutions to two-piont boundary value problem.

第五部分借助Lyapunov函数法，通过将第二类边值问题的解对结成第一类边值问题的解，得到了二阶广义系统的第一类边值问题解的存在性；通过将两点边值问题的解对结成三点边值问题的解，得到了三阶广义系统的三点边值问题解的存在性和唯一性。

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。

Besides, the author also give a detailed analysis and conclusion from the four levels of the total layout, building flat surface layout, building space and the exterior space shape. First, the thesis analyzed the race building, aim at the special natural environment and social milieu, i.e. how its total layout is; the concrete nature adaptability to the natural and social features. Second, this thesis analyzes the feature of layout in this origin with the examples of store, house, general residence, house, courtyard, public buildings and the clues of person's living mode. Furthermore, the thesis launches from street space, courtyard space, indoors space to explore the villages and living room of the nationalities such as 汉,土家,苗,侗. Finally, the thesis gives a specific analysis of the exterior space and nature factor, unreasoned composition of exterior space and fortuity, the relationship between the exterior space and function, the exterior space and geography and hang feet floor and horoscope doors and fence etc.

首先，论文分析了民族建筑针对特殊的自然环境与社会环境，其总体布局如何；具体体现自然适应性和社会适应性的特色：其次，论文以店宅、一般住宅、宅院、公共建筑四种湘西民族建筑类型为主，以相应的人的生活模式为线索，分析湘西民族建筑的平面布局特色；再者，论文从街道空间、院落空间、室内空间三个部分展开，同时对湘西地区汉族、土家族、苗族、侗族的村镇和民居建筑空间分别进行了颇有民族特色的着力探寻；最后，论文分外部空间造型与自然因素、外部空间造型的非理性与偶成、外部空间造型与功能关系、外部空间造型与地形关系、吊脚楼及八字门与围墙等六个部分，具体分析湘西民族建筑外部空间造型特色。

For the purpose of extending the applicability of the coupling method to the bidimensional exterior steady Oseen problem, we will introduce a smooth artificial boundary separating an interior inhomogeneous region from an exterior homogeneous region .The solution in the exterior region is represented by an integral equation over the artificial boundary.

为了将这种耦合方法应用于二维外部定常的Oseen问题，我们人为的引入一条光滑的边界，将内部非均匀区域和外部均匀区域分离，外部区域的解可以由人工边界上的积分方程来描述，此积分方程同内部区域的速度-压力变分形式结合为耦合变分形式，我们则可以使用有限元的方法求解此耦合变分方程。

The network space is the typical form of abstract space when it comes to the digital stage.

网络空间是抽象空间数字化阶段的典型形式。

The Notarial System,as the system of judicial certification in our country,is both the constructor and the defender of social credit system,It has its special value and function in the social honesty.

公证制度作为我国司法证明制度，既是社会信用体系的建设者，同时也是社会信用的捍卫者，在诚信中有其特殊的价值和功能。