边界单元法

Basing on the transfinite mapping concepts, the present author developed a program system with an automatic mesh generator for 2-dimensional finite elements and graphical display, which is capable of generating various types of element meshs including that of 4-node, 8-node and 9-node quadrilateral elements, automatically deals with boundary conditions and load information, so that it is convenient to apply finite elament method to practical engineering problems.

利用超限映射理论，建立了一个二维有限元网格自动生成和图形显示为一体的程序系统。该系统能生成多种类型的单元（4节点、8节点、9节点），自动处理边界条件和荷载信息，使有限元法能方便地运用于实际问题。

Secondly, the construction simulation were performed by the model in ANSYS. The effect were emphasized in the construction process, which induced by temperature, geometric nonlinearity, and boundary condition. The conclusions were given that the stress decreased thirty percent for temperature change 10℃, and decreased fifteen percent for considering the elasticity support.

基于单元生死法施工模拟原理，运用ANSYS有限元软件建立了体育馆屋盖模型，进行了施工过程数值模拟，重点探讨了温度效应、几何非线性及支承条件对结构受力性能的影响规律，同时指出支承柱临界截面的存在，温度效应和边界条件变化对网壳结构边桁架杆件受力影响最为显著，温度变化10℃影响达30%，考虑支承弹性的影响在15%以上。

First the FEM-BI (Finite Element – Boundary Integral Methods) base on vector element is presented to compute the electric field in the cavity backed antennas.

计算中首先采用基于矢量单元的"有限元－边界积分方程法"计算出背腔天线内部电场的分布；再采用互易原理求解天线的远区场，从而获得天线的辐射方向图。

In the upper bound approach, the velocity of each node are seen as unknown quantity, with the conditions of flow rule, velocity discontinuity, velocity boundary, the energy work equation considered, then the strength safety coefficient of slope, and the corresponding kinematically admissible velocity field are obtained.

在上限法中，以结点速度为未知量，根据单元塑性流动约束条件、速度不连续约束条件、速度边界约束条件，以及由外功功率与内功功率相等条件得到的目标函数，求得了强度储备系数的上限值及相应的机动容许位移场。

DSPR (Dynamic Scanlines Post-Reallocation) algorithm changes the boundary of block assigned to each Transputer after each operation, so that the total number of strips needed to travel around the network can be decreased, and then decrease the cost of communication.

DSPR后动态扫描线分配算法的出法点是运算后根据运算参数动态地改变分配给处理单元的显示区域的边界，这样就可以减少需要传送的不属于自己区域内的条码数量，进而减少运算后的通信开销。

In this paper, the primary terms in closed form, which are essential to the influence of interference effects of the notches are obtained by means of the modification of body force densities, the adoption of local coordinates with respect to the center of each notch element and the decomposition of Melan's fundamental solutions. Thus an improved body force method is proposed for analyzing interference effects of random boundary notches subje-cted to complex loads.

本文通过修改体积力密度的定义、引入建立在各缺口单元中心处的局部坐标并分解Melan基本解，获得了影响缺口群相互干涉效应的主项封闭解，从而建立了能有效地分析复合载荷作用下任意边界缺口群相互干涉效应的改进型体积力法。

Chrysanthemum of 10 thousand birthday is lax to edaphic requirement, with the arenaceous qualitative loam with fecund, good drainage had better.

万寿菊对土壤要求不严，以肥沃。排水良好的砂质壤土为好。

He unstepped the mast and furled the sail and tied it.

他拔下桅杆，把帆卷起，系住。