数值函数

The new method is a combination of characteristic approximation to handle the convection part, to ensure the high stability of the method in approximating the sharp fronts and reduce the numerical diffusion, a smaller time truncation is gained at the same time, and a mixed finite elementspatial approximation to deal with the diffusion part, the sealer unknown and the adjoint vector function are approximated optimally and simultaneously.

此方法即为对方程的对流项沿流体流动的方向即特征方向进行离散，从而保证格式在流动锋线前沿逼近的高稳定性，消除了数值弥散现象，并得到了较小的时间截断误差；另一方面，对方程的扩散项采用混合元离散，可同时高精度逼近未知函数及其伴随向量函数，理论分析表明，此方法是稳定的，具有最优的L~2逼近精度。

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。

The mutual coherence and angular correlation function of scattered wave from two dimensional rough surfaces is derived with Integral Equation Model and then calculated for perfectly conducting rough surfaces, then the scattering of incident pulse wave with different shape is calculated and the shape of scattered pulse is presented.

采用积分方程法推导出了二维粗糙面的双频互相关和角相关函数，数值计算了具有不同粗糙度的良导体粗糙面的双频互相关函数，在此基础上分别计算了二维粗糙面对δ脉冲、Gaussian脉冲和矩形脉冲的散射，并给出了散射脉冲的波形。

One bases on function value and another bases on arithmetic average difference quotient. In this paper, the author mainly studies the approximation properties of both the function value and the derivative of two kinds of splines interpolation mentioned before, and the optimal error constants are obtained finally.

文中分别就这两类插值样条的函数值及一阶导数的逼近性质展开讨论，相应得出这两种插值函数在被插函数分别为一阶连续可导和二阶连续可导情况下的最佳误差常数。

In this paper, based on the Bessel function, an Ordinary Differential Equation was derived for time-domain Green function and its gradients in this paper. A new efficient calculation method based on solving ODE is proposed.

在探索求解精度和计算效率的矛盾中，提出了结合求解常微分方程的节点制表、节点间插值的快速计算Gre en函数的方法并据此开发了一套三维深水时域Green函数的数值计算程序。

The numerical experiment results by researching the optimal problem of standard test functions show that the election-survey algorithm can constringe rapidly to global optimal solution and has better stability.

通过对标准测试函数优化的数值实验结果表明，竞选算法可快速搜索到函数的全局最优解，并具有较好的稳定性。

Several important matrix function such as e〓, log (1+A), cos (1+A) and A〓 are approximated via truncated matrix continued fractions, and the error bounds associated with the continued fraction approximants of these matrix function are given.

在第六章，我们研究了矩阵函数的数值计算，我们给出了几个比较重要的矩阵函数如e〓，log（1+A），cos与A〓的连分式逼近算法，并给出了各自的误差分析。

In this paper, A new global convex filled function and several concrete forms of a two-parameters filled function are given.

针对这些填充函数进行了分析证明和数值实验，结果说明了该填充函数的有效性。

The value of the cosine function at argument x.

参数为x的情形下余弦（在原正弦函数中x取余角）函数的数值。

The case study shows that the shape functions and their derivatives of the meshless Kriging interpolation method have the properties of Kronecker delta function.

数值算例结果证明该法构造的形函数具备过点插值性质并且具有很好的曲线拟合特性，是一种非常好的无网格法形函数。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。