有限元法

The sub-modeling technique of finite element analysis or FEA is studied as an alterative numerical method.

箱形结构中应力集中部位椭圆形表面裂纹区域的名义应力场分布不规则，无法使用现有的解析解和经验公式，有限元子模型法是求解此类问题的途径之一。

However the computation of the finite element method is very complex when dealing high-dimensional problems. So that in order to solve the multi-variables problems, the alternating- direction method appears. It can lower the dimension.

有限元方法虽然具有高精度的优点，但是在处理高维问题时计算很复杂，因此为求解多变量的复杂问题，出现了交替方向法，可以把多维问题降维，分解成连续解几个一维问题。

This method has some virtues comparing with the former two methods: First, temperature field could be computed without experiments if power dissipation of components is known, that means it can be apriority.

这种方法较采用有限元与有限差分法模拟温度场分布有几个优点，首先，如果元器件功耗已知，温度场的分布可以在不做实验的情况下就计算求得，做到了真正的先验性。

To research the frame as one system and find the congruous pre-tightening load, the finite element analysis models of combined frame are built up with selected Lagrange multiplier algorithm as contact arithmetic and applying pre-tightened force element.

为将机身作为一个系统来进行分析以确定预紧力，选择拉格朗日乘子法作为接触算法，并结合预紧力单元解决组合式预应力机身的有限元建模问题。

The basic equations are expanded in asymptotic linear equations of each order according to small parameter of incident wave's field by perturbation method.

近年来随着计算技术的发展，有限元等数值法已广泛应用于波与结构相互作用'的计算分析。

Those equations are dispersed in space by iso-parameter elementmethod and in time by using backward difference. A numerical simulator is established byFortran, the ideas of high part make the of structure program clear, maintain easy, calculationeffective.

在此基础上利用Fortran语言编制了有限元方法的油藏模拟器，采用等参元对渗流方程在空间上离散，采用向后差分在时间上离散，线性方程组的求解采用变带宽高斯消去法，该方法充分利用刚度矩阵呈条带状和其对称性的特点，大大减少了所需存储空间。

Regarding small convergence interval of conical degree as machinery sealed ring basic principle of structure optimization,with the maximum contact pressure as goal function,with the wear allowance of float ring as designing variable,the first order optimization method was applied to carry on thermal-structural coupling finite element optimization analysis of machinery sealed ring.

以小锥度的收敛间隙为优化原则，以最大接触压力作为目标函数，以静环端面的磨损裕度为设计变量，采用一阶优化法进行机械密封环热-结构耦合有限元优化计算。

By comparison, the ray grouping method produce agreed fields with the finite-element ray tracing method implemented by BELLHOP. Furthermore, it is free of singularities and the calculation speed can increase by more than 30 percent.

声线分组法与现有由BELLHOP程序实现的有限元方法相比计算结果具有很好的一致性，并且能够避免奇异点的产生，同时解算速度可以提高30%以上。

To design and analyze 95% Chinese crash dummy, a method that base on human body mechanics and finite element analysis was used, and a 95% Chinese crash dummy was researched and manufactured.

基于人体力学和有限元分析法，针对95％国产碰撞假人设计中的关键性问题进行了设计和分析，完成了95％国产碰撞假人的研制。

A finite element method with boundary element method is presented for computing electromagnetic induction.

提出了用有限元－边界元法计算三维电磁场感应问题。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。