数值算法

And the control volume finite difference method based on the boundary fitted curve line coordinate for the coupling model of whole system;(2)introduction of the relative temperature gradient function Sv , which is used to determine the evolution of crystal / melt interface shape, because the shape of the crystal / melt interface during crystal growth is an important factor in determining the crystal quality.

本文采用数值模拟方法，研究了传热对晶体生长的影响，包括以下几个方面：(1)建立了晶体的简化模型，熔体的简化模型和相应的数值计算方法；为了从总体上研究晶体生长的动态特性，首次导出了旋成体曲线座标系的SIMPLEC算法，并成功地应用于晶体生长的整体模拟。

First, we discuss the noncharacteristic Cauchy problem for 1-D heat equation.

首先，对一维的热传导方程的非特征Cauchy问题，我们利用边界积分方法将问题的求解转化成解积分方程组的问题，再对积分方程组进行离散化来数值求解，最后的数值结果表明我们的算法是有效的。

For PDEs with small parameters, a scheme is AP if it possesses the discreteanalogy of the continuous asymptotic limit as the small parameter goes to zero.

对于含有小参数的偏微分方程，所谓一个算法是渐近保持的指的是，当相应的数值离散在小参数趋于零的时候，仍然是渐近极限的合理数值离散。

But in our method, the reference function value of the iteration point is defined by a special weighted average, i.e., a convex combination of all previous function values.

而在此算法中，迭代点的参考函数值为一特殊的加权平均值，即前面所有点函数值的凸组合。

This paper uses the non-uniform grid model successfully to fulfill the three-dimensional simulation modeling of the double post-hole convolute whose structures are complex; uses strut to fulfill the load modeling of the computer implementation; explores the feasibility and application value of using MPI parallel algorith into the simulation.

成功地使用了非均匀网格模型，实现了对结构复杂的中心汇流区的三维数值建模；运用金属支撑杆模型，实现了负载的数值建模。探讨了MPI并行算法运用到模拟中的可行性及其应用价值。

In Chapter 2, starting from the basic fractional ordinary differential equations,weapply a high order approximation of fractional derivative advanced by Lubich to frac-tional differential equation, construct a high numerical difference scheme to solve thefractional differential equation, present error analysis of the algorithms theoretically,and prove the consistency ,convergency and stability.

接下来的第二章中，首先从基本的分数阶常微分方程出发，对Lubich提出的一个关于分数阶导数的高阶近似，将其应用于分数阶微分方程，构造高阶数值差分格式来进行分数阶微分方程的数值求解，并在理论上给出这一算法的误差分析，证明了它的相容性，收敛性和稳定性。

In this paper, we construct the differential equation to solve the unconstrained optimization problem. Such methods solving the ill-conditioned problems are very effective. It indicates that the asymptotically stable region of explicit the Euler method to solve the differential equation equals to the descent region of the gradient method to solve the original unconstrained optimization problem.

我们发现，在用Euler方法求解二次优化问题的等价动力系统的方程时，由方法的步长确定的稳定区域对应于这些方法所得到的迭代公式的步长满足单调下降算法的条件确定的单调下降区域，因此我们可以利用这个性质构造解无约束优化问题的数值方法而不采用标准的常微分方程的数值求解公式。

Here, the theory and the deducing process of the SEM based on the Legendre polynomial is given. The SEM can get a global diagonal mass matrix, which leads to a very simple explicit time difference scheme and high efficiency. Numerical simulation in the transversely isotropic medium are shown and the results approved that the SEM is a effective method for seismic wave modeling.

文中阐述了基于Legendre多项式的谱元法的理论和推导过程，该方法可以形成全局对角质量矩阵，在时间域使用显式的差分算法，提高运算效率，最后通过横向各向同性介质的数值计算，模拟结果表明该方法是一种有效的数值模拟方法。

The SEM can get a global diagonal mass matrix, which leads to a very simple explicit time difference scheme and high efficiency. Numerical simulation in the transversely isotropic medium are shown and the results approved that the SEM is a effective method for seismic wave modeling.

文中阐述了基于Legendre多项式的谱元法的理论和推导过程，该方法可以形成全局对角质量矩阵，在时间域使用显式的差分算法，提高运算效率，最后通过横向各向同性介质的数值计算，模拟结果表明该方法是一种有效的数值模拟方法。

With the knowledge of linear algebra, general formula for arbitrary order Taylor finite difference has been derived. In this paper, the analysis of spectral property and computational error of arbitrary order TFD is presented in detail. Then it is applied into the numerical solution of Maxwell's equations. Stability condition and numerical dispersion relation are derived.

本文借助于采样定理，详细分析了不同阶Taylor中心差分格式的谱特性以及计算误差，并将任意阶Taylor中心差分格式用于数值求解麦克斯韦方程中，严格导出了稳定性条件和数值色散关系的表达式，引入了新的误差定义来衡量算法的好坏。

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。