查询词典 finite difference approximation

The initial-boundary value problem for hyperbolic equation in one-dimensional domain with moving boundary is studied. The discrete time finite element approximation is suggested, and its stability is proved.

研究了具有变动边界的一维区域上的双曲型方程的初边值问题；提出一类全离散有限元逼近格式，并证明了格式的稳定性。

The infinite dimensional inverse problem was approximated by a problem in the finite dimensional space by using approximation theory.

将该算法应用于复杂函数的自动演化建模，也取得了理想的效果，因此该算法具有良好的通用性。

The result gives a theoretic guarantee for the finite approximation of the formula that is an infinite series.

确定了头部模型后，应提出相应的前向计算公式来求偶极子在头皮上产生的电位分布。

In the hybrid algorithm, we use FEM to model the EM field in the interior domain, and then use the integral equation to compute the field on the boundary (to provide an artificial boundary condition for FEM system), and the finite element approximation is also convenient for deriving discrete equations of the integral equation.

混合法的原理是引入一个包围非均匀目标体的虚构边界，在边界内部的场用有限元法模拟，在边界外部的场用积分方程表达，二者在边界上通过场的连续性耦合起来。

The main goal of this article is the application of Lagrange multiplier to domain decomposition for generalized Stokes problem; This method is very suitable to the finite element space approximation.

本文的主要目的在于将Lagrange乘子技术应用于广义Stokes问题的非匹配网格上的区域分裂解法中；这种方法非常适用于有限元空间近似。

According to the result, the confidence region of unknown parameters in single-index models is constructed. Finally, we consider the test of correlation and heterogeneity for hierarchical nonlinear mixed-effects models. According to Laplace approximation expansion of integrated log-quasilikelihood, a class of score test statistics is proposed. Under some very mild conditions, we prove the asymptotic distribution of the test statistics is a standard X~2-distribution. Through a Monte Carlo simulation study, the finite sample performance is examined.

最后，我们研究的第四个问题是分层非线性随机混合效应模型的相关性与异方差性检验问题，依据对数拟积分似然的Laplace近似展开提出了检验统计量，在一些正则条件下，得到了检验统计量的渐近分布是一个标准的χ~2-(来源：d7d7A65BC论文网www.abclunwen.com)分布，通过Monte Carlo模拟研究了其小样本的表现，实例验证了其实际应用。

In this paper,based on an improved orthogonal expansion in an clement , using the new idea of Ref.[3] ,a new error expression of n-degree Hermite finite element approximation to one-dimensional 4-degrec 2-point bounded problem and 2-degree ordinary differential problem, and then optimal order superconvergence for their first derivatives is obtained.

本文针对在改进的单元正交性估计的基础上，利用文[3]提出的新想法，得到一维四阶两点边值问题和二阶常微初值问题的n次赫米特有限元u_h∈C~1的新误差估计式，以及导数误差的最佳阶超收敛，并且两者有相同的超收敛结果。

Secondly, point out that meshless method is different from finite element method in handling boundary condition and numerical integral because the approximation function of meshless method is not inserted function, it have itself special methods. Deduces meshless Galerkin essential equation of parabolic partial differential equation with the method ofweighted residuals------Galerkin. Furthermore, discusses the main factors which may effectthe calculation precision and give some suggestion with which can get the best result.

其次，由于无网格法的近似函数不是插值函数，所以无网格Galerkin法在处理边界条件和对区域积分时是不同于有限元的，它有其独特的处理方法，从加权残量法——Galerkin出发，推导出抛物型偏微分方程无网格Galerkin法的基本方程，并对影响无网格Galerkin法的主要因素进行探讨，给出了取得最佳效果的相应建议。

Basing on the variation principle of solid-fluid coupled problem,on the situation of the tank being full filled,the essential method and principle have been found by using the numerical approximation of finite element method.

在罐车满载的情况下，根据固液耦合问题的广义变分原理，使用有限元的近似数值计算方法，找到解决满载罐车液固耦合振动问题的基本方法和原理，建立铁路罐车的固液耦合问题的动力学控制方程，并通过算例验证液体对罐车耦合振动的影响，得到在工程上所需要的分析结果。

In chapter 10, we propose the random weighting approximation method for distribution of sample mean under simple random sampling in one-dimensional finite population.

第十章 将随机加权法首次应用到简单随机抽样方案下的样本均值分布逼近问题中，从数字特征角度说明了随机加权方法在抽样理论中的可用性，从而拓广了随机加权法的应用范围。

We have something to do in the new stage.

在这段崭新的时期中，我们有一些要做的。

The difference between tourism decision-making under uncertainty and risky tourism decision-making is indistinctive.

其中不确定性旅游决策和风险旅游决策的界线比较模糊，两者的区分是相对的。