查询词典 numerical method

The characteristic approximation is used to handle the convection part along the direc-tion of fluid namely characteristic direction to ensure the high stability of the method in approximating the sharp fronts and reduce the numerical diffusion; The mixed finite element spatial approximation is employed to deal with diffusion part and approximate the scalar unknown and the adjoint vector function optimally and simultaneously; In order to preserve the integral conservation of the method, we introduce the modified characteristic method.

该方法对方程的对流部分沿流体流动的方向即特征方向离散以保证格式在流动的锋线前沿逼近的高稳定性，消除数值弥散现象；对方程的扩散部分采用最低次混合有限元方法离散、同时以高精度逼近未知函数及未知函数的梯度；为保证方法的整体守恒性，在格式中引入修正项。

Advanced numerical simulations were introduced in soil water research,such as finite analysis method,characteristic finite element method,and alternating direction finite element method.

土壤水研究的数值模拟方法也有一些突破，如有限解析法、特征有限元法、交替方向有限元法等。

Furthermore, we constructed group explicit method, alternating group explicit method and alternating section explicit-implicit method. The last two methods are unconditionally stable. The numerical results show that our methods have good accuracy.

分析表明，通过格式在不同时间层的交替，如分组显式方法、交替分组显式方法、交替分段显-隐方法，后两种方法是绝对稳定的，而且数值试验表明计算精度较好。

To variational inequalities with separate structures, the thesis presents a descend method based on the alternating directions method, and some numerical results demonstrate that the new method is effective in practice.

对于结构可分的变分不等式，本文在交替方向法的基础上提出了一种下降方法，并给出了相应的算法收敛性证明与数值试验结果。

The explicit form of this method is very similar to that of the Newmark explicit method while its numerical characteristics are exactly the same as those the constant average acceleration method.

此新发展的外显式积分法其一般式和Newmark外显式积分法非常相似，然而，它的数值特性却完全与等平均加速度积分法一样。

The Schur subspace iteration method is applied for the dynamic characteristic analysis of damped structure vibration system and coupled fluid－structure system. This method avoids complex computation and has good numerical stability. A accelerated technique and a pre－process method for the system matrix are suggested to improve the computational efficiency. The generalized uncoupled equation is obtained from the Schur matrix and a back substitution scheme of response computaton is developed.

第三部分将非对称特征值问题的Schur子空间迭代法应用于非经典阻尼结构振动系统和流固耦合系统的特征值分析，建立了相应的具体算法，并给出了用以提高迭代收敛速度的迭代加速和矩阵预处理等实用技术；利用Schur矩阵的结构特点，推导了系统方程的动力解耦形式，给出了响应计算的回代求解格式。

General method, including steepest descent method, conjugate gradient method and Dynamic Programming, is to search piecewise functions as the approximation with numerical methods on the base of Bellman\'s principle of optimality or the Hamiltonian function.

动态规划与智能仿生算法尤其适用于梯度信息不可得的情况。单一的优化方法用于不同情况下的化工动态优化问题未必可行有效，为此本文针对具体情况，提出了多种解法的集成策略。

Based on the "10th Five-Year Plan" industry key project of " high-speed-precise numerical controlled lathe"" high speed precise numerically controlled lathe" funded by Jiangsu Province (Approved No:BE2001068), the theory and its application such as dynamic virtual design , and modeling and correcting model corrected modeling on combine surface, disposition for parts partition walls, and the method of dynamic optimal design on the whole lathe was comprehensively and systemically studied. A new design plan of numerical controlled numerically controlled lathe was made put forward .

鉴于此，本文围绕江苏省十五重大工业攻关项目&高速高精度数控车床&的开发（批准号：BE2001068），在机床结构的动态虚拟设计、紧固结合面的动力学建模及模型修正、部件筋板布局和车床整机的动态优化设计等方面进行了全面、系统、深入的理论和应用研究，提出了一种新的数控车床的设计方案。

To observe global/local failure in macro- and micro-scope respectively, and to speed up numerical approach for some cases, this research also tries to combine PFC2D software with the finite difference method of FLAC code to carry out three issues:(1) uniaxial test; and (2) Brazilian test to assess this linking/coupling numerical algorism, then (3) indentation fracture test in rock by a single-cutting tool.

本研究并於国内首次使用分离元素法软体PFC2D与有限差分法软体FLAC两二维数值软体进行贯切破坏之数值耦合运算，利用耦合概念加速分析之运算速度，两软体之连结透过力与速度之交换传递。

The numerical solution of carbon diffusion was solved and the finite difference method was used, the inner boundary conditions of the meshes were treated using diffusional flux and carbon's activity, and adaptive software was assembled. The system of identification indicated that the numerical results were accordant to the expermental results.

用有限差分法寻求异种接头碳扩散的数值解，利用扩散通量和扩散驱动力活度的知识处理了网格的内边界，编制了相应的软件，辨识结果表明用有限差分法进行异种接头界面碳扩散迁移的定量计算和状态辨识与试验结果的分布趋势是一致的。

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。