四面体

As hexahedral mesh has more advantages than surface mesh and tetrahedral mesh, a research hotpot is concentrated on hexahedral mesh generation algorithm.

由于六面体网格在很多方面具有其它面网格和四面体网格无法比拟的优越性，所以研究热点都集中在六面体网格算法的研究上。

We can now use tetrahedron and hexahedron elements in three-dimensional stress analysis.

我们现在在三维应力分析中采用四面体单元和六面体单元。

The calculation accuracy and the calculation efficiency of hexahedron mesh generated by author are higher than tetrahedron element.

所剖分的六面体单元的－计算精度和计算效率都高于四面体单元。

The unit type was the mixture between tetrahedron and hexahedron.

产生的单元类型为四面体与六面体的混合。

The main contributions of the dissertation are as follow:(1) The possibility of generation hexahedron mesh through tetrahedron conversion method was studied,and a set of feasible method to deal with the boundary condition of constraint and loads has been brought forward.

本文的主要工作包括如下几个方面：(1)研究了在紫瑞CAE基础上采用四面体转换法进行六面体网格全自动剖分的可行性并对约束和载荷的处理提出了一套可行的方案。

A kind of complete automatic subdivision method for mesh of hexahedron based on quadratic subdivision of tetrahedron was put forward and the corresponding program was developed.

提出了一种基于四面体二次剖分的六面体网格全自动剖分方法，研制了相应的程序。

The shape of the tetrahedron, which shows a triangle from four different sides, was generated by space ships nearby, coordinating with one another, thus a type of holograph.

它是四面体的形状，从4 个不同的角度看都呈三角形，是由附近的太空船所产生的。

Additionally, there was new AES that may be a transition form of hybridism of carbon atom. It is concluded that carbon atom of graphite changes from sp^2 π to sp^3 through "metal catalyst layer", and deposits on the surface of diamond.

结果表明高温高压条件下石墨中碳原子经过"金属催化剂层"才能将碳原子的电子构形从SP^2π态改变成SP^3态，碳原子从而以金刚石四面体结构沉积到金刚石表面，金刚石晶格结构的形成是在金刚石表面层完成的。

This method has been used to calculate electronic structures of the icosahedral,tetrahedral and dihedral fullerenes and some stability rules are obtained.

这种方法已经用于系统地研究具有二十面体群、四面体群和二面体群对称性的各富勒烯同系列，并且得到规律性的结果。

Plato conjectured each of these elements to be made up of a certain Platonic solid: the element of earth would be a cube, of air an octahedron, of water an icosahedron, and of fire a tetrahedron .

柏拉图推测每一种元素都是由某些理想立方体组成：地元素是由立方体组成，风元素是一个八面体，水元素是二十面体，火元素是四面体。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了