一类具有无穷时滞和功能反应的捕食扩散系统的持久性与稳定性

研究一类非自治的具有HollingⅡ类功能性反应且包含时变时滞与多个无穷时滞的两种群n斑块捕食扩散系统的持久性与稳定性.利用比较原理,结合构造Lyapunov泛函的方法,得到了保证该系统永久持续生存和任意正解全局渐近稳定的充分性条件.     

基于比率的三种群混合扩散模型的动力学行为

讨论了一类基于比率的非自治三种群混合扩散模型,三种群间既有捕食关系又有竞争关系.我们研究了该模型的动力学行为:包括一致持久性,全局渐近稳定性,周期解,概周期解的存在唯一性.表明即使食饵种群在某些孤立的斑块中可能绝灭,也可以通过适当选取扩散率来保证系统持续生存.     

具有连续时滞和功能性反应的非自治竞争系统的持续生存

本文利用Lyapunov-Razumikhin理论讨论了具有连续时滞和Ⅱ类功能性反应的非自治扩散竞争系统．此系统有两个种群n个斑块，其中一个种群可以在n个斑块中自由扩散，另一种群被限定在一斑块中不能扩散．当系数满足一定的条件时，证明了系统是持续生存的，此外，给出了该系统的一周期解全局吸引的充分条件．     

生态扩散系统全局渐近稳定的条件

本文研究一类带扩散的非自治捕食系统,该系统由ｎ个斑块组成,食饵种群可以在ｎ个斑块之间扩散,而捕食者种群限定在一个斑块不能扩散．得到系统持续生存和全局渐近稳定的条件．     

一类Lotka-Volterra捕食-竞争扩散系统的概周期解

研究了一类带扩散项的n种群Lotka-volterra非自治捕食-竞争系统，应用Liapunov泛函方法得到系统持久生存和存在唯一全局渐近稳定正概周期解的新的充分条件，并举例说明定理的应用．     

一类Lotka-Volterra竞争生态系统的周期解

讨论一类特殊的n种群LotkaVolterra竞争生态系统的周期解,应用拓扑度理论中的延拓定理和Lyapunov泛函方法,得到了这类系统周期解的存在性和全局渐近稳定性的充分判据.     

一类具有时滞和比率依赖的竞争扩散系统

研究了一类具有时滞和基于比率的两种群非自治竞争扩散系统.利用比较原理证明了系统在适当条件下是一致持久的;利用B row er不动点原理和构造Lyapunov泛函,得到了系统存在唯一全局渐近稳定周期正解的充分条件.     

具有反馈控制和功能反应的两种群竞争系统的解的渐近性

讨论了具有反馈控制和功能反应的两种群竞争系统的解的渐近性质,获得了在一定条件下该种群持续生存的充分条件,以及该系统为周期系统时,存在全局渐近稳定的正周期解。     

五种群Lotka-Volterra混合系统的全局渐近稳定性

考虑周期系数的五种群Lotka-Volterra模型,种群间既有捕食关系又有竞争关系,得到该系统的正周期解的存在性及全局渐近稳定性的条件.     

具有连续时滞的非自治扩散Lotka—Volterra模型的周期解

本文研究了一类具有周期系数和连续时滞的两种群非自治扩散模型,确定了保证存在一个全局渐近隐定的正周期解的充分条件．     

Persistence and periodic orbits for two-species nonautonomous diffusion lotka-volterra models

This paper considers a competing system in which one of two species can diffuse between two patches, while the other is confined to one patch and cannot diffuse. It is proved that the system can be made persistent under some appropriate conditions even if the competitive patch is not persistent without diffusion. Further, if the system is a periodic system, it can have a strictly positive periodic orbit which is globally asymptotically stable under the appropriate conditions.     

ON THE NONAUTONOMOUS PREDATOR-PREY LOTKA-VOLTERRA DIFFUSION SYSTEMS

OneofthemostinterestingquestionsinmathematicalbiologyconcernsthesurvivalofspeciesillecologlcalmodeIs.InthispaPer,weconsiderallonaut0nomous8ystemc0mPosedoftwospeciesPredatox-Preywithdiffosion.1nfaCt,dffesion0ften0ccursinanecologicalenvir0nment.thatistosay,speciescandchsebetweenpatches.Levin[1]firstestablishedthiskindofmodelaboutanautonomousLotkaVolterrasystem,afterLevin,Kishdriot0[2]andTakeuchi[3jalsostudiedthiskind0fmodels-Butallthecoefficientsinthesystemtheystudiedareconstant's0itisrealls…     

具有反馈控制和Beddington-DeAngelis功能性反应的非自治扩散模型的概周期解

讨论了一类具有反馈控制和B edd ington-D eA ngelis功能性反应的非自治捕食-食饵扩散模型,其中食饵可以在两个斑块有限制地扩散,但对捕食者来说,斑块间的扩散不受限制.本文结合运用Lyapunov函数,得到该模型存在唯一的全局渐进稳定的正概周期解的条件.     

Asymptotically periodic solution and optimal harvesting policy for Gompertz system

In this paper, the single species modelled by (asymptotically) periodic Gompertz equation is investigated. It is shown that the (asymptotically) periodic system has a unique (asymptotically) periodic solution which is globally asymptotically stable for the positive solution. When the nonautonomous Gompertz equation is subject to harvesting, we study the optimal harvesting policy for the periodic system and obtain the corresponding optimal population level and the maximum sustainable yield. Further, when the functions in the exploited Gompertz system are stably bounded functions, we study the ultimately optimal harvesting policy. By choosing the average limiting maximum sustainable yield as management objective, the corresponding optimal population level is determined.     

一类Lotka-Volterra互惠扩散系统的概周期解和全局稳定性

In this paper a nonautonomous two-species n-patches system is studied.Within each patch,there are two cooperative species and their dynamics are described by the LotkaVolterra model.Each species can diffuse independently and discretely between its interpatch and intrapatch.By constructing a suitable Liapunov function,some sufficient conditions are obtained for the existence of a unique globally asymptotically stable positive almost periodic solution.     

比率型-捕食者-两竞争食饵模型的动力学行为

本文研究比率型非自治的捕食者 -食饵模型 .该系统是两个具有竞争关系的食饵种群被一个捕食种群捕食 .我们研究其动力学行为 ,包括持久性 ,全局渐近稳定性 ,周期解 ,概周期解的存在唯一性     

Threshold dynamics for a cholera epidemic model with periodic transmission rate

A cholera epidemic model with periodic transmission rate is presented. The basic reproduction number is defined. It is shown that the disease-free equilibrium is globally asymptotically stable and the cholera eventually disappears if the basic reproduction number is less than one. And if the basic reproduction number is greater than one, there exists a positive periodic solution which is globally asymptotically stable. Numerical simulations are provided to illustrate analytical results.     

Asymptotics of the solution of a system with constant delay

We study a complicated linear homogeneous system with constant delay consisting of two subsystems, one of which contains an exponential factor multiplying the right-hand side. Under some conditions, we prove the existence of an asymptotically periodic solution of this system.     

具有反馈控制的离散两种群竞争系统的概周期解

对于具有反馈控制的离散概周期两种群竞争系统的概周期解问题,进行了深入的讨论,得到了该系统存在唯一的一致渐近稳定概周期解的充分条件.     

ASYMPTOTIC BEHAVIOR OF THE POSITIVE SOLUTION OF A NONAUTONOMOUS FOOD-CHAIN MODEL WITH DIFFUSION

A nonautonomous food-chain system with diffusion is investigated in this paper, whose coefficients asymptotically approach periodic functions. Under some sufficient conditions all positive solutions of the system asymptotically approach the periodic solution of the corresponding periodic system, by using comparison theorem and constructing Lyapunov-type functions.