查询词典 finite element method

The present method is more accurate than the finite element and boundary element method.

将几组典型数据的计算结果与FEM-BEM组合法计算结果的比较表明，该方法是准确和快速的。

Firstly, this paper investigated roundly the basic theory of the ambient vibration method, analyzed systematically the main methods of ambient vibration identification, and discussed their advantages and disadvantages. Then we established the finite element model of structural dynamics and test model and analyzed their mutual relation, improved MUSIC method and correlation function method in the harmonic identification, and gave the subspace method and correlation function method based on continuous model, which is multi-harmonic retrieve technique. And then, this paper also puts forward least-squares method to estimate directly structural physical and modal parameters; this approach replaced the derivative operator in the continuous time model with an equivalent approximation, and estimated the physical parameters of structures by the least-squares method. And then, we discussed the approximation methods of derivative and their convergence. Finally, this paper researched the modal parameters of a frame structure by the simulation and test. The results demonstrated that subspace method, correlation function method and the least-squares method are effective and stable respectively.

全面地研究环境振动识别方法的基本理论，系统地分析环境振动识别方法的主要方法，讨论它们的优点和不足；建立结(来源：6666AB44C论文网www.abclunwen.com)构动力学的有限元模型和试验模型，分析有限元模型与试验模型之间的相互关系；改进谐波识别中的MUSIC识别方法和相关函数识别方法，给出大型结构模态识别的连续型的子空间分解识别方法和相关函数识别方法，这个方法是多元谐波识别方法；提出直接识别结构的物理参数和模态参数的最小二乘方法，这个方法利用导数的近似值代替导数值，并运用最小二乘方法识别结构的物理参数，讨论导数近似值的选择方法，分析算法的收敛性；通过仿真计算和模型实验，研究高层框架结构的模态参数识别，验证子空间分解识别方法、相关函数识别方法和最小二乘识别方法的有效性，算法的稳定性；从理论和试验两个方面分析和研究噪声对识别精度的影响，影响识别精度的因素，以及部分模态成分的模态参数不能够被识别的原因。

The results of calculation indicate, utilizing the spline finte point method to carry on the analysis of the intellectual structure, the model is simple, the physics relation is very clear. Comparing with the finite element model, the spline finite point method has greater superiority.

计算结果表明，利用样条有限点法进行智能结构的分析，计算模型简单，物理关系明确，与有限元法相关的计算模型相比，具有较大的优越性，实用价值高。

In consideration of these complicated factors, Duncan—Chang model is used for the soil in this paper, and the deep excavation is modeled by using the method of coupling of multiple finite elements such that calculation results approach to actual condition. In addition, based on the theory of increment method, dynamic simulation using the finite element methods is investigated for the deep excavation.

考虑到众多复杂因素的影响，本文采用邓肯—张模型做为土的本构模型，使用该模型进行计算能够较为充分地考虑到各种复杂因素的影响，而且实际工程中对于邓肯—张模型的参数变化情况已积累了较丰富的经验：采用多种形式有限元耦合的方法对深基坑问题进行建模，从而达到使计算结果接近实际的目的。

A novel method of data processing between the finite element deformation results and the surface distortion of optical element was presented and compared with the traditional method.

提出了一种新的有限元变形结果与光学元件面形畸变之间的数据处理方式，并与传统方式进行了对比。

An optimum design for the complex body formed together with the volute casing, base ring and cement foundation of a hydraulic turbine is made by the gradient method and a program is developed on the basis of finite element analysis with the plane and shell element, body element, boundary element and pseudo element.

本文对由水轮机蜗壳、座环和水泥基础所构成的复杂组合体，在采用板壳元、块体元、边界元和伪单元等四类单元进行有限元分析的基础上，选用最速下降法研究了优化设计过程，并编制成程序系统。

The finite element model included two types of main element: beam element for concrete and truss element for internal unbonded or external tendon. The end nodes of main elements were connected with internal constraints named MPC in ABAQUS. Spring elements with very large stiffness were set up at the place of the deviators of externally prestressed beams, or along the span with relatively little space of unbonded internally prestressed beams. The modified Riks method is utilized to trace the entire structural response of beams prestressed with unbonded tendon from zero to ultimate loads. The reliability of the analysis model is verified by analytical results of typical test beams in comparison with experimental ones.

该有限元模型由两类主单元组成，即混凝土梁单元和体内无粘结或体外预应力筋桁架单元；主单元的端部节点用ABAQUS的内在约束MPC连接；在体外预应力梁的转向块处，或沿体内无粘结预应力梁全跨并以比较小的间隔设置刚度足够大的弹簧单元。

At present, the common numerical methods are finite difference, finite element , boundary element, integration equation and transmission line method.

目前，解决这类问题的数值方法主要有有限差分法、有限元法、边界元法、积分方程法、传输线法等。

The inner force of the line element for underground structure have been calculated using the traditional finite element mesh and high-order manifold method to guarantee the numerical precision of the line element and overcome the disadvantages due to the geometry error between the actual position and computational position of the beam and truss element in common use.

用传统的有限元网格和流形方法的高阶覆盖位移函数来进行地下结构的杆、梁单元计算，保证了线单元模拟的数值精度，同时又克服了常用的杆、梁线单元计算位置与实际位置不相符合从而带来计算误差和结构设计不便等缺点，提供了一种解决结构数值计算的较好的途径。

Then after a semi-rigid joint behavior can be modeled as a finite stiffness rotation spring, base on rotation and displacement equation derive the element stiffness matrixes with semi-rigid connections where the effects of jointed flexibility and shear forces in the connection deformations have been considered in and fixed-end forces are modified. Finally, a program for calculating system reliability of semi-ridge steel frames with Monte carlo method and finite element analysis has compiled for calculating and analyzing.

接着本文在介绍和分析半刚性连接弯矩和转角关系模型的基础上，用带有转动刚度的弹簧表征半刚性连接，推导出半刚性连接的刚度矩阵，对固端力进行修正，同时考虑了剪切变形的影响，编制了半刚接钢结构平面框架的有限元程序BHPFL，并在其基础上编制了基于蒙特卡洛法的Monte Carlo-BHPFL 有限元相结合的方法，进行体系可靠度的分析。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。