PERMANENCE AND GLOBAL STABILITY TO A NONAUTONOMOUS NONLINEAR DISCRETE SINGLE SPECIES SYSTEM

In this paper,we study some permanence and global stability to a nonau- tonomous nonlinear discrete single species system,and obtain some sufficient condition of global stability to the system.     

On global stability of a nonresident computer virus model

In this paper, we establish new sufficient conditions for the infected equilibrium of a nonresident computer virus model to be globally asymptotically stable. Our results extend two kind of known results in recent literature.     

The asymptotic behavior of a class of nonlinear delay difference equations

The asymptotic behavior of difference equations of type 0, \end{equation*}">is studied, where and each are continuous real functions with decreasing and increasing. Results include sufficient conditions for permanence, oscillations and global attractivity.

     

PERMANENCE OF GENERAL NONAUTONOMOUS SINGLE-SPECIES KOLMOGOROV TYPE SYSTEM WITH DELAY AND FEEDBACK CONTROLS

In this paper, we consider the general nonautonomous single-species Kolmogorov type system with delay and feedback controls. Sufficient conditions for the permanence of species are established. Our results generalize some known results.     

具有阶段结构的竞争系统的持久性和稳定性

研究带有时滞和成长阶段的两种群竞争模型,第一个种群分成年和幼年两个阶段,第二个种群不具有阶段结构.本文证明了系统正解的有界性;利用比较原理得到了系统永久生存的充分条件;通过构造Lyapunov函数得到了系统全局渐近稳定的充分条件.     

一个具有时滞和功能反应的非自治阶段结构的捕食模型

研究一个具有时滞和功能反应的非自治阶段结构的捕食模型,其中食饵种群分两个阶段——幼年和成年,且捕食种群只捕成年食饵.通过利用微分不等式、比较定理和构造适当的Lyapunov泛函,得到该模型的永久持续生存和绝灭的充分条件,同时也得到了周期系统存在唯一全局渐近稳定的周期解的充分条件.     

一类带有Holling Ⅱ类功能性反应和相互干扰及脉冲效应的捕食系统

A kind of predator-prey system of Holling typeⅡand interaction perturbation with impulsive effect is presented.By using Floquet theory and small amplitude perturbations skills,the locally asymptotical stability of prey-eradication periodic solution and the permanence of the system are discussed and the corresponding threshold conditions are given respectively.Finally,the existence of positive periodic solution is investigated by the bifurcation theory.     

PERMANENCE OF A PERIODIC PREDATOR-PREY SYSTEM WITH DISPERSAL AND GENERAL HOLLING TYPE FUNCTIONAL RESPONSE

In this paper, a set of sufficient conditions which ensure the permanence of a periodic predator-prey system with dispersal and general Holling type functional response are obtained. Our results generalize some known results.     

无规丁苯共聚物的核磁共振波谱——二单元序列结构的定量计算

在前文谱带指认的基础上,用¹³C-NMR谱的脂肪碳部分计算了无规丁苯共聚物中十六种二单元的组成.由它们推出的四种结构单元的组成与从氢谱得到的结果相符.在本聚合体系下,二单元的序列长度和四种结构单元的平均持续比表明,苯乙烯单元(S)易形成短嵌段聚合物,1,2-丁二烯单元(v)显示出易与其它三种单体单元结合的趋势,反式1,4-丁二烯单元(t)和顺式1,4-丁二烯单元(c)除形成本身的嵌段聚合物以外,也易形成交替式结构.结果表明,¹³C-NMR是研究丁苯共聚物微观结构的有力工具.     

Global attractivity and almost periodic solution of a discrete mutualism model with delays

In this paper, we consider an almost periodic discrete Lotka–Volterra mutualism model with delays. We first obtain the permanence and global attractivity of the system. By means of an almost periodic functional hull theory and constructing a suitable Lyapunov function, sufficient conditions are obtained for the existence of a unique strictly positive almost periodic solution, which is globally attractive. An example together with numerical simulation indicates the feasibility of the main result. Copyright © 2013 John Wiley & Sons, Ltd.