迭代计算

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。

In this study, symmetric successive overrelaxation preconditioned conjugate gradient algorithm is used to solve large linear system derived from 3-D finite-element resistivity forward modeling. Using row-indexed sparse storage mode to store coefficient matrix, the algorithm converges much quickly and requires much less storage of computer.

引入对称超松弛预条件共轭梯度迭代算法求解电阻率三维有限元计算形成的大型线性方程组，并有机结合系数矩阵的稀疏存储模式，使得三维有限元正演计算的速度大大提高而内存需求则大大减少。

The effective heat-transfer temperature difference of every effect of multi-effect evaporation subsystem and the preheat temperature rise Δt_(p,j of every level of multi-level preheat subsystem of the design model were distributed by equal heating area, equal heat-transfer temperature difference, and free proration methods.

设计型模型对多效蒸发子系统各效有效传热温差Δt_i的分配和多级预热子系统各级预热温升Δt_的分配分别采用等面积法、等温差法、自由配比法等进行分配并采用矩阵法结合迭代法进行设计模拟计算，其中自由配比法巧妙地将具有复杂约束条件的决策变量Δt_i和Δt_转化为取值0～1的中间决策变量τ_i、τ_，为Δt_i和Δt_的自由搜索进而为优化设计提供了一个简便的方法；在常规设计模拟计算的基础上，建立了复杂多效蒸发系统优化设计模型，该模型以系统年总费用最小为优化目标，以生蒸汽温度T_0、冷凝器中二次蒸汽温度T_K、蒸发温差配比系数τ_i和预热温升配比系数τ_为决策变量，采用遗传算法结合矩阵法求解。

It is emphasized in this paper that the recomputation under the nonlinear conditions and also with different data dependency in context is the core of solving the problem of the contradiction between cost complexity and spatial cost.

同时本文强调，研究非线性情形下的重复计算以及三种数据相关性(即变量的依赖相关、IO相关和迭代相关)，是有效解决微分模式较高计算时间和空间存储代价难题最为根本的出发点之一。

The recursion formula for calculating WOB are established by means of the mechanical analysis.

通过力学分析，推导出计算钻压的迭代公式，即建立了计算井底钻压的力学模型。

It shows that the method is very efficient for applications in YiChang Yangtse Rive Bridge.

宜昌长江公路大桥的应用表明，该解析迭代的系统计算方法，收敛速度快、精度高，是一种有效计算方法。

Data of tooth surface before and after wear were both obtained through laser scan system. The images were then reconstructed by SURFACER software.(2) C language program used of improved iterative closest point algorithms was developed to registrate imagines before and after wear. Standard plan was defined to the overlapped imagines after registration, then wear quantity was measured.￤ear was imitated by tooth brush machine which was made by STOMATOLOGY COLLEGE FORTH MILITARY MEDICAL UNIVERSITY.

应用三维激光扫描仪采集牙模型的表面数据，在计算机中用SURFACER逆向工程软件重建牙表面；②运用最近邻点迭代匹配算法加以改进，编制 C语言程序，配准磨耗前后的三维图像，在确定基准平面后，计算磨耗前后的体积变化量；③用口腔医院自制刷牙机进行模拟磨耗，用传统称重法，通过电子天平测试件的重量变化，用失水法计算测试材料的密度，换算成体积。

Levin pine Act TOEPLITZ symmetric matrix solution composed of linear equations, fewer iterations, the computational complexity is at the end of time, and the calculation accuracy is very high, is a very good way!

详细说明：列文松法解对称TOEPLITZ矩阵组成的线性方程组，迭代次数少，计算复杂读很底，且计算精度相当高，是一种非常好的方法！

It means that any computable object in Turing machine can be defined itera tively and computed efficiently with Pure logic.

这就等于证明了，任何图灵可计算的对象都可用纯逻辑迭代地定义和高效地计算。

The obtained results a re compared with analytic solution and those from integral equation and other me ans. It is shown that the staggered grid finite difference method combined with the Biconjugate gradient iterative solver processed with divergence correction and incomplete Cholesky decomposition procedures can efficiently improve the three dimensional electromagnetic calculation with high accuracy and stability.

经与解析方法、积分方程等其他方法的计算结果对比表明，交错网格有限差分法结合散度校正和不完全乔累斯基分解预处理的双共轭梯度迭代方法进行正演计算，速度快、精度高、结果稳定，能适应三维复杂介质的数值模拟，为三维电磁反演奠定了基础。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。