非自治多种群时滞Kolmogorov系统的持续性和灭绝性

研究非自治多种群时滞Kolmogorov系统,给出了该系统中种群持续和灭绝的充分条件,并把得到的结果应用于非自治时滞Lotka-Volterra系统.把相关文献的有关结果推广到时滞系统.     

具周期系数的单种群模型及其最优捕获策略

该文用一种新的方法, 讨论了单种群生物资源的捕获优化问题.以最大的可持续单位时间捕获量为管理目标, 得到一类非自治单种群捕获模型的最优捕获策略, 所得结果包括了文献中研究过的几乎所有单种群捕获模型的相应研究结果.     

具有阶段结构和周期投放的非自治单种系统的周期解

研究一类带周期投放的非自治阶段结构单种群模型,利用泛函微分方程的单调和凹算子理论,得到系统存在一个全局吸引正周期的充分条件。     

一类自治单种群模型及其最优捕获策略

用一种新的方法,讨论了单种群生物资源的捕获优化问题.分别以单位时间最大可持续捕获量和单位时间最大净利润为管理目标,得到一类自治单种群捕获模型的最优捕获策略,所得结果包括了文献中研究过的几乎所有自治单种群捕获模型的相应研究结果.     

自治单种群模型及其最优捕获策略

本文用一种新的方法,讨论了单种群生物资源的捕获优化问题.分别以单位时间最大可持续捕获量和单位时间最大净利润为管理目标,得到一类自治单种群捕获模型的最优捕获策略,所得结果包括了文献中研究过的几乎所有自治单种群捕获模型的相应研究结果.     

具有时滞的非自治Lotka-Volterra竞争系统的持久与灭绝

本文研究具有纯时滞的一般Ｎ－种群非自治Ｌｏｔｋａ－Ｖｏｌｔｅｒｒａ竞争系统的持久性和灭绝性．一些新的判别准则被建立．文献［８－１０］中得到的关于无时滞非自治Ｌｏｔｋａ－Ｖｏｌｔｅｒｒａ竞争系统的结果被改进和推广．     

具有时滞的一类N-种群非自治竞争系统的持久性(英文)

讨论了具有时滞的一类N-种群非自治竞争系统.建立了系统持久的新条件.推广了文献[1]中的结果.     

具有时滞的非自治Lotka-Volterra竞争系统的持久与灭绝

本文研究具有纯时滞的一般Ｎ－种群非自治Ｌｏｔｋａ－Ｖｏｌｔｅｒｒａ竞争系统的持久性和灭绝性．一些新的判别准则被建立．文献［８－１０］中得到的关于无时滞非自治Ｌｏｔｋａ－Ｖｏｌｔｅｒｒａ竞争系统的结果被改进和推广．     

一类非纯时滞非自治Lotka-Volterra竞争系统的持久性

讨论一类非纯时滞非自治Lotka-Volterra竞争系统,通过改进[4],[5]和[6]中一些方法,得到所有种群持久的充分条件,其结果推广了[4]的结论.     

具有脉冲效应非自治捕食系统的研究

研究了具有脉冲效应的非自治捕食系统,该系统是两个具有互惠关系的食饵种群被一个捕食种群捕食.利用重合度理论证明系统正周期解的存在性.     

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.     

The persistence and global attractivity in general nonautonomous discrete single-species Kolmogorov model with delays

In this paper, general nonautonomous discrete-time single-species Kolmogorov model with delays is studied. Some sufficient conditions on the boundedness, persistence, permanence and global attractivity of solutions are established. As application, the discrete time nonautonomous delayed Allee-effect model is discussed. The sufficient conditions on the permanence and global attractivity are obtained.     

Persistence and stability in general nonautonomous single-species Kolmogorov systems with delays

This paper studies the general nonautonomous single-species Kolmogorov systems with delays. The sufficient conditions on the persistence and permanence of species, global asymptotic stability and the existence of positive periodic solutions are established. As applications of these results, the permanence, global asymptotic stability and the existence of positive periodic solutions for a series of special single-species growth systems with delays are discussed.     

The dynamical behaviors of a nonautonomous Holling III predator-prey system with impulses

In this paper, we study a Holling III nonautonomous predator-prey system with impulses. Firstly, the dynamics of single-species nonautonomous Logistic system with impulses are discussed. Further, based on these results and by impulsive differential comparison theorem, the extinction and permanence of Holling III nonautonomous predator-prey system with impulses are obtained.     

Carrying simplices in nonautonomous and random competitive Kolmogorov systems

The purpose of this paper is to investigate the asymptotic behavior of positive solutions of nonautonomous and random competitive Kolmogorov systems via the skew-product flows approach. It is shown that there exists an unordered carrying simplex which attracts all nontrivial positive orbits of the skew-product flow associated with a nonautonomous (random) competitive Kolmogorov system.     

Almost sufficient and necessary conditions for permanence and extinction of nonautonomous discrete logistic systems with time-varying delays and feedback control

A class of nonautonomous discrete logistic single-species systems with time-varying pure-delays and feedback control is studied. By introducing a new research method, almost sufficient and necessary conditions for the permanence and extinction of species are obtained. Particularly, when the system degenerates into a periodic system, sufficient and necessary conditions on the permanence and extinction of species are obtained. Moreover, a very important fact is found in our results, that is, the feedback control and delays are harmless for the permanence and extinction of species for discrete single-species systems. This shows that in a discrete single-species system introducing the feedback control to factitiously control the permanence and extinction of species is useless.     

Uniform persistence for nonautonomous and random parabolic Kolmogorov systems

The purpose of this paper is to investigate uniform persistence for nonautonomous and random parabolic Kolmogorov systems via the skew-product semiflows approach. It is first shown that the uniform persistence of the skew-product semiflow associated with a nonautonomous (random) parabolic Kolmogorov system implies that of the system. Various sufficient conditions in terms of the so-called unsaturatedness and/or Lyapunov exponents for uniform persistence of the skew-product semiflows are then provided. Among others, it is shown that if the associated skew-product semiflow has a global attractor and its restriction to the boundary of the state space has a Morse decomposition which is unsaturated or whose external Lyapunov exponents are positive, then it is uniformly persistent. More specific conditions are discussed for uniform persistence in n-species, particularly 3-species, random competitive systems.     

Global attractivity of nonautonomous stage-structured population models with dispersal and harvest

The nonautonomous stage-structured single-species dispersal model with harvesting of mature individuals in an N-patch environment is considered, in which the individual members of the population have a life history that takes them through two stages, immature and mature. By using the theory of monotone and concave operators to functional differential equations, we establish conditions under which this population dynamical system admits a positive periodic solution which attracts all positive solutions.     

非自治Kolmogorov竞争系统的严格正解

In this paper, the existence of strictly positive solutions for N species normutonomous Kolmogorov competition systems is studied. By applying the Schauder‘s flxed pointtheorem some new sufficient conditions are established. In particular, for the almost periodicsystem, tile existence of strictly positive almost periodic solutiorts is obtained, Some previousresults are improved and generalized.