查询词典 finit element method

Firstly, the three-dimension boundary question and its corresponding variation question concerning the point-source electrical field on a 3-D structure are presented. Secondly, the finite element method is used to solve the variational equation. The study area is divided into many tetrahedral elements. Then, we interpolate with a tri-linear function in each element. So, the variational equation is converted into a linear equation system. Finally, taking into account saving of time, we make use of symmetric successive overrelaxation preconditioned conjugate gradient algorithm to solve large linear system, and obtain the potential value of each node, resulting in the calculation of the apparent resistivity values on the ground surface.

首先给出了三维构造中点源电场的边值问题以及相应的变分问题；然后利用有限单元法求解变分问题，采用四面体单元对研究区域进行剖分，在单元中进行三线性函数插值，将变分方程化为线性代数方程组；最后，考虑到节约计算时间，利用对称超松弛预条件共轭梯度迭代算法求解大型线性方程组，得到了各节点的电位值，进而计算出地表的视电阻率。

A finite element model of 3-3 piezocomposites was established according to the homogenization method, which combined the techniques relying upon representative volume element and periodic boundary conditions.

压电复合材料是由至少一种压电材料与非压电材料按照一定的连通方式组合在一起而构成的一种具有压电效应的新材料[1]。3 3 型压电复合材料是指压电相和非压电相分别三维连通的压电复合材料。

Based on the 4 nodes element used for piezoelectric composite laminate plate and finite element method,and using sensitivities of structural displacements with respect to actuator voltages,the static deformation control considering smoothness requirement for platelike adaptive structure with piezoelectric material layers as actuators is studied in this paper.

基于四节点压电复合材料层合板单元和相应有限元分析方法，利用结构位移对电压的灵敏度，对以压电材料为作动器的板壳自适应结构，进行了考虑平整性要求的静力变形控制。

Secondly, two methods are combined into a 2D classifying method and again the current highway information foundation data elements are classified in 2 Dimensions. The problems in data element set are pointed out and also the expand idea is put forward. The key properties of 2D classifying data element are studied.

将2种分类方法结合形成二维数据元分类方法，并对现有公路信息基础数据元重新进行了分类，指出存在问题并给出了数据元扩充的思路，对二维数据元的关键属性进行了研究。

In this article author measured the principal element and trace element of Maifanshi with X-ray fluorescence spectrometric method of analysis.

本文用X-射线荧光光谱分析法对麦饭石中的主元素和微量元素进行了测定，测定结果达到检出线的有24种，其中有些是人体所必需的元素。

Based on the transmission gears, this paper has studied systematically the method of fatigue lifetime prediction under stochastic loads, through probability statistics, finite element and fatigue analysis. The influences of uncertainty of load statistical distribution, finite element model and mechanical performance parameters of material on fatigue life prediction are analyzed.

本文以传动齿轮为研究对象，应用概率统计、有限元和疲劳分析，深入、系统地研究了自行火炮传动齿轮在随机载荷作用下疲劳分析与寿命预测的理论方法，分析了载荷统计分布、有限元模型和材料力学性能参数的不确定性对疲劳寿命预测的影响。

We in this paper present a composite grid method based on the system of finite element program generator to solve finite element problems with local singularity, which often occurs in engineering and scientific computing.

针对工程计算中经常出现的局部特性问题，和以往解决此类问题的算法的局限性，提出一种基于有限元自动生成系统的组合网格算法。

Using the Updated Lagrange finite element method and the elastic-plastic large deformation finite element formula based on virtual work-rate principle of finite deformation, the author studies in detail the plastic flow rule of MPF, including the influence of the work hardening index, friction, thickness of sheet, material, number and position of the punch.

作者采用逐级更新Lagrange法以及有限变形虚功率增率原理的弹塑性大变形有限元法，详细研究了金属板材多点成形的塑性流动规律，包括加工硬化指数、摩擦系数、板料厚度、材料、冲头个数及位置等对成形的影响，同时探讨了分段成形时的金属流动规律。

For the raft, an isoparametric element method and VoigtKelvin model are adopted, which can be used to derive viscoelastic element stiffness matrices, a reform of successive approximation of Rayleigh Quotient is used to solve the eigenvalue problem of the composite structure.

对于筏架结构，采用Voiget-Kelvin模型及等参元法，推导了约束阻尼层单元的刚度阵及将Rayleigh商的迭代步骤加以改进的方法来进行特征分析；对于艇体结构与声学介质耦合部分，采用艇体结构的"干"模态作坐标变换。

Using the characteristic of the regular curve boundary for a bending plate in engineering,the analytic integral formulae of assistant states in boundary element method with the linear element for a Kirchhoff circular plate are introduced and the systematic equation of BEM is established in this paper.

利用一般弯曲薄板边界为规则曲线的特点，对工程常用的圆形弯曲薄板，采用线性单元，导出K irchhoff圆板各辅助态的边界积分解析表达式，建立问题的边界元法系统方程，从而使薄板的边界元分析完全避免通常使用的高斯积分，明显提高计算精度。

We have something to do in the new stage.

在这段崭新的时期中，我们有一些要做的。

The difference between tourism decision-making under uncertainty and risky tourism decision-making is indistinctive.

其中不确定性旅游决策和风险旅游决策的界线比较模糊，两者的区分是相对的。