含时滞的非自治单种群扩散模型的概周期解的存在性与全局吸引性

研究了含离散时滞的非自治单种群扩散模型的概周期解的存在性与全局吸引性.通过应用微分方程比较原理和不等式估计方法以及构造适当的Lyapunov函数的方法得到了系统的持久性,概周期解存在唯一性,渐进稳定性以及全局吸引性的充分条件.     

二次概周期系数微分方程的概周期解

利用指数二分性,Schauder不动点定理和Grownwall不等式证明了一类概周期系数微分方程的概周期解、有界解的存在唯一性及概周期解的全局吸引性.     

时滞细胞神经网络方程概周期解的存在唯一性

主要考虑了一类连续神经网络系统离散化情况.在一定条件下得到了这类方程概周期解的存在性和唯一性以及其全局吸引性.作为应用,最后给出一个例子.     

一类时滞微分系统的周期解和全局吸引性

本文考虑如下时滞高维微分周期系统的周期解.利用重合度理论中的延拓定理和Lyapunov泛函方法讨论了上述系统周期解的存在性和全局吸引性,得到了便于应用的新结果.     

周期时滞Logistic方程的全局吸引性

该文建立了周期时滞Logistic方程N'（t）=r（t）N（t）[1-N（t-τ）／k（t）]的正周期解的存在性，并获得了正周期解的唯一性和全局吸引性的充分条件．所得结果推广和改进了[1]的结果．     

三阶常系数拟线性泛函微分方程的周期解

研究了一个三阶泛函微分方程周期解的存在唯一性和全局吸引性：x′′′（t）＋ax′′（t）＋bx′（t）＋cx（t）＋g（t,x（tτ））=p（t）.这是一个常系数拟线性泛函微分方程.通过将这个方程转变为三维的拟线性微分方程（组）,得到了这个方程存在唯一周期解的充分条件;通过选取适当的李雅普诺夫函数,推导了这个方程解的全局吸引性;进一步,得到了此方程周期解的全局吸引性.最后,举出了两个应用实例.     

N种群周期系数非线性关系捕食—竞争系统的定性分析

本文应用比较定理，Ｂｒｏｕｗｅｒ不动点定理和Ｖ函数方法，讨论了Ｎ种群周期系数非线性关系捕食－竞争系统的正解的有界性，正周期解的存在性，正周期解的全局吸引性及唯一性。     

周期解的存在性、唯一性与稳定性

本文研究了高维周期系统的周期解的存在性、唯一性及稳定性等问题，利用指数型二分性和不动点方法，建立了保证周期解的存在性、唯一性及稳定性的充分条件，所得的结果推广了文［１、２］的主要结果。     

非线性微分方程零解的全局吸引性与包围高阶奇点的极限环的存在性

非线性微分方程零解的全局吸引性与包围高阶奇点的极限环的存在性王向荣，冯滨鲁，韩茂安（山东矿业学院数学系泰安２７１０１９）关键词：全局吸引性；极限环；存在性ＡＭＳ（１９９１）主题分类：３４Ｃ０５．考虑系统假设ｈ，Ｆ，ｇ均连续且满足解的存在唯一性条件，且...     

一类非线性泛函微分方程的周期解及全局吸引性

研究高维非线性泛函周期微分系统x(t)=A(t,x(t+·))x(t)+f(t,x(t@+·))周期解的存在性、唯一性和全局吸引性等问题,所获结果推广和改进已有文献中相关结果．     

Positive periodic solutions for impulsive predator-prey model with dispersion and time delays

In this paper, we study the existence and global attractivity of positive periodic solutions for impulsive predator-prey systems with dispersion and time delays. By using coincidence degree theorem, a set of easily verifiable sufficient conditions are obtained for the existence of at least one strictly positive periodic solutions, and by means of a suitable Lyapunov functional, the uniqueness and global attractivity of positive periodic solution is presented. Some known results subject to the underlying systems without impulses are improved and generalized.     

Nonautonomous Lotka-Volterra Systems with Delays

The paper studies the general nonautonomous Lotka-Volterra multispecies systems with finite delays. The ultimate boundedness, permanence, global attractivity, and existence and uniqueness of strictly positive solutions, positive periodic solutions, and almost periodic solutions are obtained. These results are basically an extension of the known results for nonautonomous Lotka-Volterra multispecies systems without delay to systems with delay.     

Periodic nonautonomous differential equations with noninstantaneous impulsive effects

In this paper, we study a new class of periodic nonautonomous differential equations with periodic noninstantaneous impulsive effects. A concept of noninstantaneous impulsive Cauchy matrix is introduced, and some basic properties are considered. We give the representation of solutions to the homogeneous problem and nonhomogeneous problem by using noninstantaneous impulsive Cauchy matrix, and the variation of constants method, adjoint systems, and periodicity of solutions is verified under standard periodicity conditions. Further, we show the existence and uniqueness of solutions of semilinear problem and establish existence result for periodic solutions via Brouwer fixed point theorem and uniqueness and global asymptotic stability via Banach fixed point theorem.     

高阶拟线性拟双曲型方程组

在动物神经生物学问题与液体强迫振动等问题中,经常出现具有u_(11)-u_(xx1)项的线性或拟线性方程的各种问题。在[1]中对一般化的拟线性拟双曲型方程     

Existence and global attractivity of positive periodic solutions for impulsive predator–prey model with dispersion and time delays

In this paper, we study the existence and global attractivity of positive periodic solutions for impulsive predator–prey systems with dispersion and time delays. By using the method of coincidence degree theorem, a set of easily verifiable sufficient conditions are obtained for the existence of at least one strictly positive periodic solution, and by means of a suitable Lyapunov functional, the uniqueness and global attractivity of the positive periodic solution are presented. Some known results subject to the underlying systems without impulses are improved and generalized.     

Existence and global attractivity of unique positive almost periodic solution for a model of hematopoiesis

Sufficient conditions are obtained which guarantee the uniform persistence and global attractivity of solutions for the model of hematopoiesis. Then some criteria are established for the existence, uniqueness and global attractivity of almost periodic solutions of almost periodic system.     

时滞Lotka-Volterra竞争型系统的概周期解

研究具有离散时滞的N-种群Lotka-Volterra竞争型系统，得到了系统存在唯一性概周期解的一组充分条件。     

POSITIVE ALMOST PERIODIC SOLUTIONS OF n DIMENSIONAL NONAUTONOMOUS LOTKA-VOLTERRA COMPETITIVE SYSTEMS

In this paper,we study some n dimensional nonautonomous Lotka-Volterra competitive ecological systems.We then obtain permanence of such systems, as well as the existence,uniqueness and global asymptotic stability of almost periodic positive solutions to these systems.     

Dynamics of an impulsive stochastic SIR epidemic model with saturated incidence rate

In this paper, the dynamics of an impulsive stochastic SIR epidemic model with saturated incidence rate are analyzed. The existence and uniqueness of the global positive solution is proved by constructing the equivalent system without pulses. The threshold which determines the extinction and persistence of the disease is obtained. The global attraction of disease-free periodic solution is addressed. Sufficient condition for the existence of a positive periodic solution is established. These results are supported by computer simulations.     

概周期系统概周期解的存在唯一性

应用构造Ляпунов函数的方法，讨论了非线性微分方程系概周期解的存在唯一性.同时给出了Liénard方程存在唯一概周期解的一组充分条件.