计算单元

In the second chapter, elementary theories and ideas of one step forming inverse approach were described and warped modification method, implemented by Cook, was introduced into one step forming simulation and based on idea of surface spreading; new quadrilateral element modification arithmetic was put forward. By spreading warped quadrilateral onto plane in local coordinate system, a plane quadrilateral element whose shape and area were equal to original warped quadrilateral element was gotten and internal force vectors of four nodes and stiffness matrix of elements were improved to increase precision of simulations on this plane element.

第二章从一步成形逆有限元法的基本理论和思想出发，将Cook基于弹性理论的四边形单元的翘曲修正算法引入基于塑性的一步成形，并且基于曲面展开的思想，本文提出一种新的四节点单元翘曲修正方案，通过把翘曲的单元展开的方法在局部参考系中得到一个与实际翘曲单元的形状与面积非常接近的平面单元，在该平面单元中进行单元刚度及内力向量的计算，进一步改善模拟结果的精度。

It is to divide the flow units, and then calculate the single well controlled reserves regarding the flow unit as the calculating unit, finally, compare and analyze the results from this method, single well controlled area method and dynamic pressure drawdown method respectively. The comparison result proves the scientificity and practicability of the flow unit method.

最后与通过划分单井控制面积法计算得到的单井控制储量及通过动态储量计算方法计算得到的单井动储量进行对比分析，其结果论证了流动单元法计算单井控制储量的科学性和实用性，使流动单元的研究在低渗透气田油藏精细描述中得到了进一步的推广和应用。

In the fifth part, the finite element method with sliding cable element was adopted to the prestress producing of the cable dome as well, and the computer methods and steps of the initial stiffness were established. The relevant program was worked out and was used in one example.

将本文提出的滑移单元有限元方法应用于索穹顶结构的预应力生成，并建立了初始刚度生成计算模式和步骤，编制了相应的计算程序，进行了实例计算，结果表明，本文提出的滑移单元有限元理论用于索穹顶结构的预应力生成是合理可行的，其精度已足以满足实际工程要求。

The approach of computational simulation is the finite element method.The whole research is combined by the following three parts. In part one, a program on quadtree method is compiled. It can automatically generate planar structures with all-quadrangular, good quality elements in high speed, and it can create data files on information of elements and nodes, which provide the foundation for finite element analysis. In part two, a program on finite element calculation is compiled by object-oriented method, During the simulation of fracture, the displacement and stress are calculated by the program.

本文的工作可分为三大部分：第一部分编制了四叉树法程序，通过它可对平面结构进行单元离散，快速自动生成质量较好的全四边形单元，并获得离散后的单元信息和节点信息，为有限元计算打下基础；第二部分利用面向对象方法编制了有限元计算程序，在破坏模拟过程中，利用它进行位移、应力分析；第三部分对脆性材料的破坏过程进行了模拟。

For some shortcomings of unknown quantity numbers in finite element method, QR-method establishes a transformed relationship between a unit node displacement vector and the entire framework of spline node displacement vector,making the structure of the total stiffness matrix, damping matrix, mass matrix directly superimposed in no need of finite element method in the first expansion after the superposition process. So the method greatly simplifies the calculation process and improves computing speed.

针对有限单元法中未知量数目很多的缺点，QR法建立起单元结点位移向量与整个框架样条结点位移向量的转化关系，使得结构总刚度矩阵、阻尼矩阵、质量矩阵可以直接叠加，不需要有限单元法中先扩张后叠加的手续，大大简化了计算过程，提高计算速度。

This invention provides an on-line analysis method and system for combined gas and steam cycle power station's efficiency, which comprises an on-site data-collecting unit, used to check the sub-devices state parameter in power station; a data base server linked to on-site data-collecting unit to stored the state parameter provided by data-collecting unit; modular arithmetic server used to calculate the gross operation efficiency of power station based on the data base state parameter and the influence degree caused by sub-devices property to the gross operation efficiency; client device to receive command input by clients and output the calculating result by modular arithmetic server.

本发明提供一种燃气―蒸汽联合循环发电站运行效率的在线解析方法和系统，在线解析系统包括：现场数据采集单元，用于测量电站各分设备的状态参数；与现场数据采集单元相连的数据库服务器，用于存储现场数据采集单元测量得到的状态参数；模型运算服务器，其根据从数据库提取的状态参数并计算电站的总运行效率和当前状态下电站各分设备性能对电站总运行效率的影响程度；客户机，其接收用户输入的命令并输出模型运算服务器的计算结果；网络，其将数据库、模型运算服务器和客户机连接在一起。

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。

It is proved that the method using the BEM to calculate the load distributions on the contact lines of involute gear pair, in which the applied load is taken in the form of a concentrated one at a single node, is not suitable. A method in which the tractions of the BEM are made to imitate the Hertzian pressure of the gear using 8 nodes isoparametric elements is introduced.

本文解决了边界元法在空间啮合副计算中存在的系数矩阵的存储，奇异单元积分的计算、表面不连续点处面力一点多值和求解未知量的线性方程组矩阵元素的计算等问题，编制了比不采用上述处理方法的一般边界单元法节省近一半内存和计算时间的适合空间啮合副的三维边界元法计算程序。

For some rock slopes, which have not distinct failure surface, but have complicated structure or load on the top and so on, a stability analysis of this type slopes by finite element method is presented, the failure surface is defined by certain rule or strain zone from the computed model, and then the safety factor of the rock slope is abtained by finite element method and limit equilibrium methodAt last, using ANSYS , a famous commercial finite element analysis software, a example of high-steep slope which is bearing the load of the LongGe Mansion is presented, the stability of this slope is studied, as a paradign the the stability evalution of complicated high-steep slope under the action of load of building , the chapter gives some meritable reference in stability assessment of rock slopes using numerical simulation by three-dimension elastic-plastic finite element.

并用有限单元法建立边坡的具体模型，应用折减边坡岩体参数、逐级施加荷载等与边坡工作环境相似的方法进行模拟计算，根据计算结果，采用一定的判别准则或图形可视化方法，确定出边坡的滑裂面，再采用刚体极限平衡法或有限单元法计算其安全系数；最后，通过某一工程实例，用大型有限元程序对边坡在建筑物荷载作用下的稳定性进行分析研究，并以此作为计算分析复杂高边坡在高层建筑物作用下的稳定性评价的一个范例，在采用有限元弹塑性数值模拟岩质边坡稳定性方面提供一些有价值的参考。

The main contents are as follows: Creating finite element model of cradle carriage, top carriage and trail of the howitzer. The structural static stress analysis of are dealt with finite element program system I-DEAS. For accuracy and computation cost, the nonlinear finite element structural dynamics model of the howitzer is created with different elements such as solid elements, shell elements and beam elements.

主要包括以下几个方面工作：建立了该炮摇架、上架和下架的三维有限元静力学模型，并应用I－DEAS有限元软件进行了强度分析；顾及计算准确性和计算成本，应用实体单元、壳单元和梁单元相结合的方法建立了该炮的非线性有限元结构动力学模型。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。