Time periodic solutions of porous medium equation

In this article, we study the time periodic solutions to the following porous medium equation under the homogeneous Dirichlet boundary condition: The existence of nontrivial nonnegative solution is established provided that 0≤α<m. The existence is also proved in the case α=m but with an additional assumption $\mathop{\min}\nolimits_{\overline{\Omega}\times[0,T]}a(x,t){>}{\lambda}_1In this article, we study the time periodic solutions to the following porous medium equation under the homogeneous Dirichlet boundary condition: The existence of nontrivial nonnegative solution is established provided that 0≤α<m. The existence is also proved in the case α=m but with an additional assumption $\mathop{\min}\nolimits_{\overline{\Omega}\times[0,T]}a(x,t){>}{\lambda}_1$, where λ₁ is the first eigenvalue of the operator ?Δ under the homogeneous Dirichlet boundary condition. We also show that the support of these solutions is independent of time by providing a priori estimates for their upper bounds using Moser iteration. Further, we establish the attractivity of maximal periodic solution using the monotonicity method. Copyright © 2010 John Wiley & Sons, Ltd.     

具有反馈控制的N种群非自治LOTKA-VOLTERRA竞争系统的全局吸引性

讨论了非自治N种群Lotka-volterra竞争反馈控制模型,主要采用构造适当的Lyapunov泛函的方法,同时应用Barbalat引理得到了系统全局吸引的判别准则,而且给出了周期系统存在全局吸引的正周期解的充分条件,最后利用数值模拟验证了所得结论.     

Global attractivity in delay “food-limited” models with exponential impulses

In this paper, we are concerned with the global attractivity of the positive equilibrium of the following delay “food-limited” model with exponential impulses:

     

Some problems on the global attractivity of linear nonautonomous difference equations

This paper is to solve several problems on the global attractivity of the zero solution of the nonautonomous difference equation xn+1 - xn + Pnxn-kn = 0,n ∈ Z(0), where {Pn} is a sequence of nonnegative real numbers, and {kn} is a sequence of nonnegative integers with n - kn→∞ as n→∞.     

Existence and Attractivity of Stationary Solutions of a Degenerate Diffusion Equation

This paper is concerned with the existence and attractivity of the stationary solutions of a degenerate diffusion equation. By using monotone method and applying some special techniques, we extend the-results in 1-dimension case to higher dimension cases.     

GLOBAL ATTRACTIVITY IN A PERIODIC DELAY SINGLE SPECIES MODEL

In this paper, we establish the existence of a positive periodic solution for a periodic delay single species population growth model, and obtain sufficient conditions for the periodic solution to be globally attractive.     

具一个高阶奇点的Lienard方程的全局性质

本义研究具一个高阶奇点的Ｌｉｃｎａｒｄ方程的极限环的存在在和全局吸引性，所得结果包含了著名的Ｆｉｌｉｐｐｅｖ定理，并且回答了Ｃｏｎｔｉ教授提出的一个问题。     

GLOBAL ATTRACTIVITY OF LINEAR NON－AUTONOMOUS NEUTRAL DIFFERENTIAL－DIFFERENCE EQUATIONS

ＧＬＯＢＡＬＡＴＴＲＡＣＴＩＶＩＴＹＯＦＬＩＮＥＡＲＮＯＮ－ＡＵＴＯＮＯＭＯＵＳＮＥＵＴＲＡＬＤＩＦＦＥＲＥＮＴＩＡＬ－ＤＩＦＦＥＲＥＮＣＥＥＱＵＡＴＩＯＮＳＨＥＸＵＥＺＨＯＮＧ（何学中）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，Ｎｉｎｇｘｉ...     

Permanence and convergence in multi-species competition systems with delay

The permanence and global attractivity of positive equilibria are obtained for some multi-species Kolmogorov competition models with delay by embedding the system into a larger cooperative system with delay and then appealing to the theory of monotone dynamical systems.

     

PERIODIC SOLUTION AND ALMOST PERIODIC SOLUTION OF NONAUTONOMOUS COMPETITIVE MODEL WITH STAGE STRUCTURE AND HARVESTING

In this paper, a two-species nonautonomous competitive model with stage structure and harvesting is considered. Sufficient conditions for the existence, uniqueness, global attractivity of positive periodic solution and the existence, uniform asymptotic stability of almost periodic solution are obtained.