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.     

Permanence for a nonautonomous discrete single-species system with delays and feedback control

A nonautonomous discrete single-species system with delays and feedback control is studied. New sufficient conditions for ensuring the permanence of the system are obtained. A very important fact is found in our results, that is, that the feedback control is harmless to the permanence of species. The corresponding results given in [F.D. Chen, Permanence of a single species discrete model with feedback control and delay, Appl. Math. Lett. 20 (2007) 729–733] are improved and extended.     

Permanence and global attractivity for discrete nonautonomous two-species Lotka-Volterra competitive system with delays and feedback controls

A discrete nonautonomous two-species Lotka-Volterra competitive system with delays and feedback controls is proposed and investigated. By using the method of discrete Lyapunov functionals, new sufficient conditions on the permanence of species and global attractivity of the system are established. Particularly, an interesting fact is found in our results, that is, the feedback controls are harmless to the permanence of species for the considered system.     

Permanence of a delayed discrete mutualism model with feedback controls

This paper discusses a two species discrete model of mutualism with delays and feedback controls. Sufficient conditions are obtained for the permanence of the system. The results show that feedback control variables have no influence on the persistence property of the system.     

一类具有时滞和反馈控制的非线性离散模型的持久性

研究了一类具有时滞和反馈控制的非线性单种群离散模型的持久性,获得了该系统持久的充分条件,并通过例子表明结果的可行性,所得结果推广了已有文献的相关结果.     

Permanence of species in nonautonomous discrete Lotka–Volterra competitive system with delays and feedback controls

A nonautonomous N-species discrete Lotka–Volterra competitive system of difference equations with delays and feedback controls is considered. New sufficient conditions are obtained for the permanence of this discrete system. The results indicate that one can choose suitable controls to make the species coexistence in the long run. Moreover, we give some examples to illustrate the feasibility of our result which can be well suited for computational purposes.     

具时滞和反馈控制的修正Leslie-Gower离散系统的持久性

提出并研究具有反馈控制变量和Holling-Ⅱ类功能性反应的修正Leslie-Gower离散捕食系统的持久性问题,通过运用差分不等式得到了一组保证该系统持久的充分性条件．该结果表明反馈控制变量不会影响系统的持久性从而改进了已有的结果．数值模拟显示了本文结果的可行性．     

PERMANENCE IN A SINGLE SPECIES NON-AUTONOMOUS SYSTEM WITH PURE-DELAY AND FEEDBACK CONTROL

In this paper, we consider a single species non-autonomous system with pure-delay and feedback control. Sufficient conditions of integrable form for the permanence of species are established.     

Permanence and almost periodic sequence solution for a discrete delay logistic equation with feedback control

In this paper, we consider a discrete delay logistic equation with feedback control. By applying the theory of difference inequality and constructing a suitable Lyapunov functional, sufficient conditions which guarantee the permanence and existence of a unique globally attractive positive almost periodic sequence solution of the system are obtained. The result of this paper is completely new. An example is employed to illustrate our main result.     

一个离散的比率依赖Holling-Ⅲ捕食一食饵系统的持久性

本文研究了一个带有Honing-Ⅲ类功能反应和时间延迟的离散半比率依赖捕食一食饵系统，得到了该态系统永久持续生存的充分条件。     

PERMANENCE AND GLOBAL ATTRACTIVITY OF N-SPECIES COOPERATION SYSTEM WITH DISCRETE TIME DELAYS AND FEEDBACK CONTROLS

In this paper, we consider the N-species cooperation system with discrete time delays and feedback controls. By using the differential inequality theory and constructing a suitable Lyapunov functional, we obtain sufficient conditions which guarantee the permanence and the global attractivity of the system.     

Permanence of a discrete nonlinear N-species cooperation system with time delays and feedback controls

A discrete nonlinear N-species cooperation system with time delays and feedback controls is considered in this paper. Sufficient conditions which ensure the permanence of the system are obtained. It is shown that these conditions are weaker than those of Chen [F.D. Chen, Permanence of a discrete N-species cooperation system with time delays and feedback controls, Appl. Math. Comput. 186(2007) 23-29], that is, our investigation shows that the additional condition in Chen’s paper is not necessary.     

Harmless Feedback Control for Permanence and Global Asymptotic Stability in Nonlinear Delay Population Equation

In this paper, we consider whether or not the feedback control has influence on a nonlinear population equation with several time delays. The general criteria of integrable form on the permanence are established, and we note that the feedback control has no influence to the permanence of system. By constructing suitable Lyapunov functionals, a set of easily verifiable sufficient conditions are derived for global asymptotic stability of any positive solutions to the system.     

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.     

一类具有反馈控制与多变时滞Nicholson’s Blowflies模型的持久性（英文）

This paper covers the dynamic behaviors for a class of Nicholson's blowflies model with multiple time-varying delay and feedback control. By using the differential inequality theory, a set of sufficient conditions are obtained to ensure the permanence of the system.Our result shows that feedback control variables have no influence on the permanence of the system.     

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.     

Note on the permanence of a competitive system with infinite delay and feedback controls

Sufficient conditions are obtained for the permanence of a two species competitive system with infinite delay and feedback controls. It is shown that the controls can avoid the extinction of the species.     

单种群时滞反馈控制生态系统的持久性

利用细致分析的方法对单种群时滞反馈控制生态系统进行研究,获得了该系统正解持久生存的充分条件.     

时标上带有反馈控制的两种群竞争系统的概周期解

研究了一类时标上带有反馈控制的两种群竞争系统的概周期解的存在性与稳定性.首先应用微分不等式和比较原理得到了该系统的持久性.在此基础上,通过构造了一个合适的Lyapunov泛函,得到该系统存在唯一一致渐近稳定正概周期解的充分条件.文中对以前的相关文献研究结果进行了推广.     

具脉冲效应和反馈控制的企业集群竞争模型的持久性分析

根据企业集群与生物种群有着一定的相似性,借鉴种群生态学中的种群竞争模型建立了网状型企业集群模式下企业间竞争关系的数学模型-一类具脉冲效应和反馈控制的非自治企业竞争模型系统,并通过脉冲微分方程的比较性定理,建立了该系统持久性生存的充分条件,并做经济学解释.