一类非凸粘性平衡律方程的粘性激波解的存在性与稳定性

本文首先利用几何奇异摄动方法，证明了粘性系数充分小时一类非凸粘性平衡律方程的粘性冲击波的存在性，推广了原来在非线性项严格凸的条件下得到的结果．进而，利用谱分析和上下解方法，证明了对固定的小的粘性系数此类波是全局渐近指数稳定的，推广了反应扩散方程中经典的全局稳定性结果．     

平面三次H-Bézier曲线的形状分析

本文对平面三次H-Bézier曲线的形状进行分析,讨论其诸如奇点、拐点、局部凸和全局凸的几何特征,得出曲线上含有奇点、拐点和曲线为局部凸或全局凸的用控制多边形边向量相对位置表示的充分必要条件.     

Cahn—Hilliard方程的近似惯性流形

通过压缩映象原理，本文对Ｃａｈｎ－Ｈｉｌｉａｒｄ方程构造了一簇近似惯性流形，这些近惯性流越来越逼近全局吸引子。     

非自治线性时滞微分方程的扰动全局吸引性及一致稳定性

本文研究非自治线性时滞微分方程的扰动全局吸引性及一致稳定性，主要讨论了线性部分为周期系数与非周期系数的两种情形，获得了关于零解全局吸引及一致稳定的充分条件．推广了文献中线性部分为自治情形的结果。     

血生成模型的全局吸引性

在本文中，我们进一步研究时滞微分方程它由Ｍａｃｋｅｙ和Ｌａｄａｓ［２］提出作为血生成模型．我们建立了（＊）的平衡是全局吸引子的新的充分条件，我们还改进了Ｇｏｐａｌｓａｍｙ，Ｋｕｌｅｎｏｖｉｃ和Ｌａｄａｓ［１］所得到的某些结果．     

GLOBAL ATTRACTORS OF REACTION-DIFFUSION SYSTEMS AND THEIR HOMOGENIZATION

In this paper, we study the existence of the global attractor A^ε of reaction-diffusion equation δtu^ε(x,t)=Aεu^ε(x,t)-f(x,ε^-1x;u^ε(x,t)).and the homogenized attractor ,A^0 of the corresponding homogenized equation, then give explicit estimates for the distance between the attractor .A^ε and the homogenized attractor ,A^0.     

The Global Convergence of Self-Scaling BFGS Algorithm with Nonmonotone Line Search for Unconstrained Nonconvex Optimization Problems

The self-scaling quasi-Newton method solves an unconstrained optimization problem by scaling the Hessian approximation matrix before it is updated at each iteration to avoid the possible large eigenvalues in the Hessian approximation matrices of the objective function. It has been proved in the literature that this method has the global and superlinear convergence when the objective function is convex （or even uniformly convex）. We propose to solve unconstrained nonconvex optimization problems by a self-scaling BFGS algorithm with nonmonotone linear search. Nonmonotone line search has been recognized in numerical practices as a competitive approach for solving large-scale nonlinear problems. We consider two different nonmonotone line search forms and study the global convergence of these nonmonotone self-scale BFGS algorithms. We prove that, under some weaker condition than that in the literature, both forms of the self-scaling BFGS algorithm are globally convergent for unconstrained nonconvex optimization problems.     

中国省域高校科技竞争力演化分析

科技竞争力是国家和区域竞争力的决定性因素。本文将具有时序性特征的全局主成分分析(GPCA)方法引入我国省域高校科技竞争力动态演化研究之中。根据评价方法及评价对象的特点,构建了评价指标体系,并对我国1998-2002年的30个省域高校科技竞争力动态发展演化进行综合分析。结果表明,1998-2002年,我国省域高校科技竞争力发展水平差距缩小,波动明显,竞争激烈。省域经济发展与高校科技竞争力相互关系不确定。     

The Cauchy Problems and Global Solutions to the Deybe System and Burgers＇ Equations in Pseudomeasure Spaces

In this paper we consider the Cauchy problems of Burgers＇ equations and the Deybe system. Their existence and uniqueness of the time-global solutions for small initial data in some pseudomeasure spaces are obtained. The asymptotic stability of small solutions is proved. As an immediate result the existence and uniqueness of the self-similar solutions are also obtained provided the initial data satisfy the self-similar structures.     

时滞差分方程的吸引性

本文给出了时滞差分方程x_n+1=x_nf(x_n,x_n-1),n=0,1,…解的全局吸引性的一个新的充分条件;作为应用,部分解决了G.Ladas的一个猜想.