查询词典 partition of unity

On the basis of the idea of partition of unity, a discontinuous function and the two-dimensional asymptotic crack-tip displacement fields are added to the displacement interpolation formula to account for discontinuity of the contact surface and stress singularity near the contact surface tip respectively. Governing equations are deduced by virtual work principle and the integral of the discontinuous functions are calculated by Gauss integral through sub-elements cut by discontinuous surface.

该方法基于单位分解思想，在位移插值形式中引入不连续函数和裂尖渐近位移场函数分别反映接触面的不连续性和接触面端点的奇异性；根据虚功原理建立有限元支配方程，接触面不连续函数积分采用分区高斯积分的方法。

When the meshless manifold method is utilized to analyze the elastodynamics, the method is divided into the major two parts: the discrete space of the domain is used to the partition of unity, which the present method void to mesh element and refine element.

在求解弹性动力学问题时，弹性动力学积分弱形式的推导采用加权残数法，空间离散采用基于单位分解法的无网格流形方法，时间离散主要采用Newmark法。

By using the partition theorem of unity, a continuous selection theorem for a multimap from a compact Hausdorff topological space to a finitely continuous topological spaces (simply, FC-spaces) without any convexity structure was obtained, and from which and Tychonoff fixed point theorem, a collectively fixed point theorem for a family of multimaps on the product space of compact FC-spaces and several collectively fixed point theorems for a family of multimaps on the product space of non-compact FC-spaces were given.

利用单位分解定理得到从紧的Hausdorff拓扑空间到没有任何凸结构的有限连续拓扑空间的集值映射的连续选择定理，并从该结果和Tychonoff不动点定理，得到紧的FC-空间的乘积空间上映射族的集族不动点定理和若干个非紧的FC-空间的乘积空间上的映射族的集族不动点定理，对文献中的相应结果进行了改进和一般化。

The controller design problem is addressed for a class of nonlinear systems by using partition of unity and variable structure control method.

采用单位分解概念和技术，结合交结构控制方法和LMI方法，讨论一类非线性系统的控制设计问题。

In order to solve the problem that matrix A often occurs irreversible when shape function is calculated by using traditional element free Galerkin method, the orthogonal function with the weight function is utilized in the paper. And partition of unity quadrature technique is employed and so a truly "meshless" method is realized.

针对传统无网格伽辽金方法在构造形函数时，矩阵A容易出现不可逆的弊端，采用带权正交基函数构造形函数，在积分方案上采用单位分解积分方法，从而实现了真正的"无网格"。

Based on the partition of unity concept, the XFEM relaxes the prohibitive requirements for mesh density by improving the shape functions with the basic knowledge of discontinuous problems.

重点介绍XFEM的基本原理、实施步骤及应用实例等，并进行必要的评述。

This thesis focuses on surface reconstruction from point cloud model, and have discussed and extended three common methods: Moving Least Squares method, Radial Basis Functions method and Multi-level Partition of Unity method.

本文以点云模型曲面重构为研究对象，研究并扩展了三种常用曲面重构方法：最小移动二乘法(MLS：Moving Least Squares Method)法，径向基函数(RBF：Radial Basis Functions method)法和多层次单元分割(MPU：Multi-level Partition ofUnity method)法。

The detailed algorithm on analyzing cracks exploration inside blocks is: enriched approximations which describe singular crack tips fields and discontinuous crack faces are employed under the Partition of Unity theory; the enriched nodes surrounding crack tips or faces are respectively mapped with corresponding enriched degrees of freedom, and the solution of all these degrees of freedom is uniformly proceeded by the implicit iteration algorithm of DDA, then fracture and breakage of DDA blocks can be analyzed. The numeric examples show this algorithm is rational and efficient.

为此建立的无网格法裂纹扩展分析算法，采用满足单位分解条件的特殊增强型函数表达裂纹周围应力场的非连续、奇异特性，将对应的扩展自由度动态映射到裂纹周围的节点上，统一按DDA法隐式迭代方式求解，实现块体裂纹扩展和强度分析，相关算例结果显示该算法是合理有效的。

More than 30 kinds of meshfree methods are reviewed in this paper in the light of weighted residual method, and different meshfree methods can be viewed as different forms of weighted residual method and/or with different approximation functions. Various kinds of meshfree approximate schemes are presented in detail, including moving least square approximation, kernel and reproducing kernel approximation, partition of unity approximation, radial basis approximation, radial point interpolation and natural neighbor interpolation.

详尽介绍了各种无网格近似方案(包括移动最小二乘近似、核近似和重构核近似、单位分解近似、径向基函数近似、点插值近似、自然邻接点插值近似等)和无网格法中常用的各类加权余量法(伽辽金格式、配点格式、局部弱形式、加权最小二乘格式和边界积分格式等)，并讨论了数值积分方法和边界条件的处理等问题。

If theharmonic index is finite,then each end may be represented by a non-constant positiveharmonic function,and these functions compose a partition of unity.For minimalhypersurfaces with finite total scalar curvature,we can explicitly estimate the harmonicindex.Moreover,the space of bounded harmonic functions are exactly generated bythose functions associated to each end.This gives geometric interpretations of the ends.

若调和指标有限，则每个端均可由一非常值的调和函数代表，它们形成了一个单位分解，对于全纯量曲率有限的极小超曲面，我们明确地估计了调和指标，进一步，有界调和函数正好由代表端的那些调和函数所生成，这就给出了端的几何解释。

It is also known as one of the most poisonous naturally occurring substances.

它也被称为一个最自然发生的有毒物质。

The greatest stress is found at the location on the cross section where V is the largest.

最大应力出现在横截面上V为最大的地方。