查询词典 parabolic differential equation

The main contents of this course include: the construction, convergence, compatibility and stability of finite difference scheme of elliptic equation, parabolic equation and hyperbolic equation, the construction method and computation format of finite difference scheme of a system of partial differential equations.

本课程主要内容有：椭圆型方程的有限差分格式的构造，有限差分格式的收敛性，相容性及稳定性、抛物型方程的有限差分格式的构造，有限差分格式的收敛性，相容性及稳定性、双曲型方程的有限差分格式的构造，有限差分格式的收敛性，相容性及稳定性、偏微分方程组的有限差分格式的构造方法及有关的计算格式。

First, the paper proves the well-posedness of the encryption and decryption problems, which provides theoretical bases for experiments of encryption and decryption; Then presents a fast iterative algorithm, which is proposed based on the special sparse structure of the coefficient matrix of the two-dimensional C-N difference scheme, and successfully experiments on images encryption and decryption; At the end, the security of the methods of images encryption and decryption based on the two-dimensional Pseudo -parabolic Partial Differential Equation is experimented and discussed particularly.

首先证明了基于二维连续模型的加、解密问题是适定的，为加、解密实验提供了理论依据；然后根据模型的二维C-N格式系数矩阵的特殊稀疏结构，给出快速迭代求解算法，并成功地进行了图像加、解密的数值试验；最后对基于二维伪抛物型方程的图像加、解密方法的安全性进行了详细的试验讨论。

Based on modern optimization theory and optimal control theory, this dissertation studies some questions as follows:1. The optimization model of parameter identification of three-dimensional geologic history numerical simulation, algorithm and its applicationGeologic history numerical simulation is a basic content of basin numerical simulation, and the porosity is the major parameter in the evolution and development process of oil-bearing basin. According to the sedimentation and burial mechanism, the physical and chemical principles of oil geology, the mudstone porositys non-linear parabolic partial differential equation has been established.

本文应用现代最优化及最优控制理论，对如下一些问题进行了研究： 1、三维地史数值模拟的参数辨识优化模型、算法及应用地史模拟是盆地数值模拟的一个基础性的研究内容，地层孔隙度是含油气盆地地史演化发育过程中的重要参数，根据地层沉积埋藏机理和石油地质的物理化学原理，通过引入数学物理方程概念，建立了泥岩三维孔隙度场方程，根据问题的特点，给出了方程的定解条件，对方程的动边界也给出了处理方法，并且证明了解的存在性与惟一性，在此基础上建立了以当今实测数据为拟合准则的三维地史数值模拟的参数辨识优化模型，这是一个含有二阶偏微分方程约束的泛函极值问题。

The first step of simulation method is to establish the one-dimension parabolic partial differential advection diffusion equation that was used to describe the mass transportation model of air-pollution distribution as a block program model of the controllable plant. Then, applying the Fuzzy logic theory to operate tunnel jet-fans and control the tunnel wind quantity and adjust the wind average velocity would not let the air-pollution concentration over the standard safety value too much.

模拟方式首先将常被用以表示隧道内空气污染物质传理论模式之一维向平流扩散抛物线型偏微分方程式建构成一组可控制对象的方块程式模拟模型，再运用模糊逻辑理论模拟控制喷流式通风机之运转风量来调节隧道内平均风速以控制隧道内空气污染物浓度不至於高过标准安全值太多。

Using the critical estimates of parabolic type partial differential equation.we ...

利用抛物型偏微分方程的极值原理，得到了带跳扩散模型下美式期权价格及最佳实施边界的误差估计。

Afterwards, the solving problem of Parabolic Type is transformed into a initial value problem of ordinary differential equation with respect to through Fourier transform again.

在数值实验中，对六个美式看跌期权价格进行了计算，通过分析比较，结果表明：快速傅里叶变换法加欧拉法是一种快速的高精度的数值计算方法。

At the beginning of fourth chapter, the article transforms the solving problem of partial differential equation for the American put price into a standard initial and boundary value problem of Parabolic Type by making some transformations.

在第四章，对美式看跌期权价格所满足的偏微分方程定解问题通过作一系列变换，使之转化为一个标准的抛物型初、边值问题，接着又通过傅里叶变换，把抛物型初、边值问题转换为一个关于时间变量的常微分方程初值问题，然后再分别利用改进的欧拉法和有限元法对其进行了求解。

The standard parabolic equation method was obtained by the decompocition of the scalar wave equation and the expansion of the pseudo-differential operator.

通过对传统波动方程的分解和伪微分算子的近似展开，获得了标准抛物线方程。

Wideangle parabolic approximations to wave equation usually lead to nonconstant differential migrators with their coefficients varying with lateral velocity variations, and hence require a finitedifference numerical implementation.

波动方程宽角抛物逼近得到的通常是非常系数的单程波传播算子，其系数是速度横向变化的函数，因此需要利用有限差分进行数值实施。

In chapter two ,we consider the Expanded Mixed Finite Method for the following quasilinear parabolic integro-differential equation.

在本章中我们给出了拟线性抛物问题的混合体积元的变分形式，并利用该方法得到了其真解与离散解的最优L~2模误差估计。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。