查询词典 calculus of finite difference

The basic idea is to set a continuous solution of the region with a finite number of discrete points instead of a grid consisting of, these discrete points called grid nodes the solution of a continuous area on a given function of continuous variables used in the definition of discrete grid variable function approximation the original equation and boundary conditions in the micro-business operators to approximate differential, integral with the points and to approximate, so the original differential equations and boundary conditions are replaced by algebraic equations near Side, that is, finite difference equations , solve this equation group can get the original problem in discrete points on the approximate solution.

基本思想是把连续的定解区域用有限个离散点构成的网格来代替，这些离散点称作网格的节点；把连续定解区域上的连续变量的函数用在网格上定义的离散变量函数来近似；把原方程和定解条件中的微商用差商来近似，积分用积分和来近似，于是原微分方程和定解条件就近似地代之以代数方程组，即有限差分方程组，解此方程组就可以得到原问题在离散点上的近似解。

In order to obtain the variation law of temperature during casting solidification to improve casting quality,a finite element method combining with a finite difference method was used to discretize time and space variables in the governing equations of astable heat-conduction in the process of casting solidification so as to obtain the algebraic equations for casting and mold temperature.

为了掌握铸件凝固过程中温度场的变化规律以提高铸件质量，采用有限元和有限差分相结合的方法离散铸件凝固过程非稳态热传导方程的空间和时间变量，得到了关于金属铸件和铸型温度的代数方程。

Compared with Finite Element Method and Finite Difference Method, Boundary Integral Equation Method is computationally more efficient.

与有限元法和有限差分法相比，该方法具有更高的计算效率。

By means of the difference discrete variational principle, discrete Legendre transformation and discrete version of the E-L cohomology, for a kind of regular meshes we''ve found there is a kind of symplectic/multisymplectic structures with corresponding symplectic/multisymplectic finite element method/mixed finite element method schemes.

利用差分离散变分原理、离散Legendre变换和EL上同调的离散形式，对于正规网格找到一类有限元和混合有限元的辛或多辛结构，以及相应的辛有限元/混合有限元格式。

On the other hand, finite difference and finite element methods use bases with small compact support but poor continuity properties.

小波基函数在空间域和频率域中都具有局部性特征，它的性质优于有限差分法、有限元法和伪谱法中所用的基函数。

In this paper, Computed water flow equation with finite difference method and solute transport equations with the Galerkin finite element method.

从国内外有关对地下水脆弱性概念的不同定义入手，通过分析和研究，提出了地下水固有脆弱性和特殊脆弱性的定义。

It combines the merit of the finite element method with that of the finite difference method.

它可以吸收有限元法和有限差分法的一些重要思想与技巧。

Authors described and analyzed the finite difference method and finite element method.

作者阐述并分析了有限差分方法和有限元方法。

An electromagnetic numerical analysis, set finite difference method, finite element method and the method of moments as one basis for teaching materials.

详细说明：一本的电磁数值分析方面的，集有限差分法，有限元法和矩量法为一体的基础教材。

When the temperature distribution is analyzed, finite element reseaus are divided in space field and finite difference reseaus are divided in time field and then, the program is compiled.

截面温度场分析在空间域内采用有限元网格划分，在时间域内则用有限差分网格划分。

You can snipe the second and third union leaders from this position.

您可以鹬第二和第三工会领袖从这一立场出发。

Aiming at the currently shortage of XML streams quality detecting, this paper proposes a new forecasting method of XML streams quality by least squares support vector machines, which is used the method of XML keys' vector matrix as windows, and vector product wavelet transform to multilevel decompose and refactor the XML streams series, that can fulfill real-time checking demand of XML quality, and ensure constraint, consist- ency and integrality. For even more adapting net load, it proposes a control strategy by weight and adaptive adjustment to ensure XML streams quality.

针对当前XML数据流质量检测存在的不足，提出构建XML键的矢量矩阵作为窗口，利用矢量积小波变换多级分解与重构XML数据流，再结合最小二乘支持向量机对XML数据流质量进行预测的一种方法，满足XML数据流质量重构时实时检测的要求，保证XML数据的约束性、一致性与完整性；为了更好的适应网络负载，采取加权与自适应窗口调整等调度策略充分保证XML数据流的质量检测。