数值方程

In this paper,a new method for estimating the global optimum value in a global optimization problem is proposed .

给出了一种全局最优化问题的全局最优值估计的新方法；该方法通过求一个非线性方程的根使目标函数值逐步减小，因此该方法具有下降算法特征。

The method using microcomputer to draw the phase graph of autonomous system on plane of ordinarily differential equation is studied,first a large number of data of orbit are obtained by an appropriate method of numerical calculation from known initial condition,then computer draw the curve of orbit on screen by these data.

研究利用微机绘制常微分方程平面自治系统相图的方法，首先用一种合适的数值算法由已知的初始条件得到轨线的大量数据，再利用这些数据在计算机屏幕上画出轨线的图形。

The stability and convergence of the fully discrete solutions are proved and the convergence order is also given.

从数值实验上也验证了该算法的可行性和高效性，对非定常N-S方程提出了一种新的全离散TGM：空间离散用标准FEM，时间离散用Crank-Nicolson格式，证明了全离散解的稳定性与收敛性。给出了收敛阶。

Based on depth averaged mathematic model of flow and pollutant tr ans portation in non orthogonal curvilinear coordinates , the k-ε double equat ions' turbulence model and the coupling arithmetic of velocity water depth are a dopted, which are applied to the numerical simulation of the flow and the contam ination diffusion transportation.

基于非正交曲线坐标下水流与污染物扩散输移的深度平均数学模型，采用k -ε双方程湍流模型和速度—水深耦合算法，应用于实验室连续弯道的水流及污染物扩散输移的数值模拟，分别计算了流场及岸边和中心污染物排放的浓度场，得到与实测值吻合良好的计算

Based on the wave equations established in general coordinate system for orthorhombic anisotropy media, this paper di...

在建立一般观测坐标系下正交各向异性介质波动方程的基础上，着重讨论了相应的伪谱法波场数值计算的稳定性条件，进而用伪谱法实现了正交各向异性介质弹性波场的正演模拟，获得了很好的模拟效果

Integrating Navier-Stokes equations with overfall model, this dissertation firstly applied CFX5. 5 solver and full coupling arithmetic to simulate air flow in flow field plates, and evaluated water management of six kinds of flow channels, the results of simulation and analysis were verified by experiments.

本文首次结合Navier-Stokes方程与湍流模型，采用CFX5.5求解器及全隐式耦合算法对对流场板内的空气流动进行了数值模拟，对不同流场板进行了水管理评价，并得到了实验的证实。

A moving overset grid method with 3D-Euler solver was used to realize the simulation of the separation process.

通过采用运动嵌套网格方法，结合三维Euler方程对飞机外挂物投放过程进行了数值模拟，并针对该投放模拟方法提出了一套合理可行的并行计算方案。

Up to now, finite difference method, finite element method and boundary element method are common numerical methods to obtain numerical solutions of parabolic partial differential equation.

目前求解抛物型偏微分方程的数值方法有有限差分法、有限元法和边界元法等。

A kind of delay parabolic partial differential equation is studied. A numerical method is proposed by discrete skill. The numerical stability for this kind of delay parabolic partial differential is analyzed by interpolation method.

研究了一类时滞的抛物型偏微分方程初边值问题，利用离散技巧，提出了一种数值方法，然后在一定插值技术下分析了算法的稳定性。

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。

For a big chunk of credit-card losses; the number of filings (and thus charge-off rates) would be rising again, whether

年美国个人破产法的一个改动使得破产登记急速下降，而后引起了信用卡大规模的亏损。

Eph. 4:23 And that you be renewed in the spirit of your mind

弗四23 而在你们心思的灵里得以更新