边界元法

In this paper the natural boundary reduction for some elliptic boundary value problems with concave angle domains and its natural boundary element methods are investigated.

本文研究凹角型区域椭圆边值问题的自然边界归化及其边界元法。

The electron trajectory in the deflection system of electron gun is calculated by using the boundary element method and the Runge-Kutta method.

采用边界元法与等效磁荷法，模拟了偏转聚焦系统的非均匀磁场，再利用龙格－库塔法模拟出电子在该系统中的运动轨迹。

Initial boundary value problem of two dimensional unsteady diffusion equations is solved in this paper. By using time-dependent fundamental solution of two dimensional diffusion equations and the extension of double layer potential, we establish virtual boundary integral expression of diffusion equations. Then virtual boundary element method is used to implement the numerical computation.

本文在求解二维非定常扩散方程的初边值问题时，利用二维扩散方程与时间有关的基本解，基于双层位势的延拓，建立二维扩散方程的虚边界积分表达式，然后利用虚边界元法进行数值计算。

In this paper, the boundary integration equations of contact problems are given according to the elastic-plastic and boundary elem...

本文根据弹塑性理论和边界元法理论推导出弹塑性接触问题的边界积分方程，给出多种接触问题研究方法、求解规则及相应的计算程序。

The nearly singular integral occurs in the boundary element formulation when a source point is close to the integration element but not on this element.

边界元法中存在几乎奇异积分的计算困难。引起边界单元上几乎奇异积分的因素是源点到其邻近单元的最小距离δ。

This paper presents the investigation of numerical stability and error estimate of SFBEM in elastic plane problems. Several conclusions regarding the above issues are obtained in this paper, which lays a solid foundation for its practical application.

本文主要针对弹性力学平面问题样条虚边界元法在数值稳定性与误差估计方面的问题展开讨论，获得了虚边界的布设规律及方法误差的直观度量，为该法的实际应用打下了更好的基础。

Up to now, finite difference method, finite element method and boundary element method are common numerical methods to obtain numerical solutions of parabolic partial differential equation.

目前求解抛物型偏微分方程的数值方法有有限差分法、有限元法和边界元法等。

The application of DRBEM to Poisson equation is discussed.

以Poisson方程为例对双互易边界元法的边界积分方程的推导以及数值实现进行了探讨。

Heat conduction equation ; Galerkin boundary element method ; Indirect boundary integral equation ; Simple layer potential2000 MSC:35F99; 35K05; 80M15

热传导方程； Galerkin边界元法；间接边界积分方程；单层位势

This simulation system will help to improve innovation design level of high-speed cultivation machine such as high-speed plow and high-speed rotary tiller. SPH; back-rotary tilling ; simulation ; soil-tool interaction ; high-speed cutting

因为牵涉到多相、松散和物性分散的耕作土壤在工作部件高速作用下的破坏过程以及破坏后土壤运动状态的描述，用连续体力学理论及其数值解法(有限单元法或者边界元法)很难描述该过程如有限单元法在大变形状况下会发生网

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。