Several new sufficient conditions are given for the global attractivity of solutions of a kind of delay difference equations. They either include or improve some known results and put the study of Ladas' conjectur...Several new sufficient conditions are given for the global attractivity of solutions of a kind of delay difference equations. They either include or improve some known results and put the study of Ladas' conjecture forward.展开更多
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 glob...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.展开更多
Some global properties such as global attractivity and global exponential stability for delayed Hopfield neural networks model, under the weaker assumptions on nonlinear activation functions, are concerned. By constru...Some global properties such as global attractivity and global exponential stability for delayed Hopfield neural networks model, under the weaker assumptions on nonlinear activation functions, are concerned. By constructing suitable Liapunov function, some simpler criteria for global attractivity and global exponential stability for Hopfield continuous neural network,; with time delays are presented.展开更多
In this paper the global attractivity of the nonlinear difference equationis investigated, where a,b, A ∈ (0,∞), k is an positive integer and the initial conditions x- k, …, x-1 and x0 are arbitrary positive number...In this paper the global attractivity of the nonlinear difference equationis investigated, where a,b, A ∈ (0,∞), k is an positive integer and the initial conditions x- k, …, x-1 and x0 are arbitrary positive numbers. It is shown that the unique positive equilibrium of the equation is global attractive. As a corollary, the result gives a positive confirmation on the conjecture presented by Kocic and Ladas [1,p154].展开更多
In this paper, sufficient conditions are obtained for the tive steady state of the delay-logistic equation to be a global attractor.An application of the results also solves aa conjecture of Gopalsamy.
A neutral difference equation with positive and negative coefficientsΔ(x n-c nx n-k )+p nx n-l -q nx n-r =0, n=0,1,2,...,is considered and a sufficient condition for the global attractivity of the ze...A neutral difference equation with positive and negative coefficientsΔ(x n-c nx n-k )+p nx n-l -q nx n-r =0, n=0,1,2,...,is considered and a sufficient condition for the global attractivity of the zero solution of this equation is obtained, which improves and extends the all known results in the literature.展开更多
We investigate a stage-structured delayed predator-prey model with impulsive stocking on prey and continuous harvesting on predator. According to the fact of biological resource management, we improve the assumption o...We investigate a stage-structured delayed predator-prey model with impulsive stocking on prey and continuous harvesting on predator. According to the fact of biological resource management, we improve the assumption of a predator-prey model with stage structure for predator population that each individual predator has the same ability to capture prey. It is assumed that the immature and mature individuals of the predator population are divided by a fixed age, and immature predator population does not have the ability to attach prey. Sufficient conditions are obtained, which guarantee the global attractivity of predator-extinction periodic solution and the permanence of the system. Our results show that the behavior of impulsive stocking on prey plays an important role for the permanence of the system, and provide tactical basis for the biological resource management. Numerical analysis is presented to illuminate the dynamics of the system.展开更多
In this paper we further study the delay differential equation N .(t)=-δN(t)+pN(t-τ)e -aN(t-τ) , t0(*) used in describing the dynamics of Nicholson’s blowflies. When p】δ ,we establish new su...In this paper we further study the delay differential equation N .(t)=-δN(t)+pN(t-τ)e -aN(t-τ) , t0(*) used in describing the dynamics of Nicholson’s blowflies. When p】δ ,we establish new sufficient conditions for the positive equilibrium N * of (*) which is a global attractor.展开更多
The existence of positive solutions and the global attractivity of the difference equation Δy n=r ny nK-y n-l n K-cy n-l n are investigated. And some sufficient conditions are obtained,which greatly imp...The existence of positive solutions and the global attractivity of the difference equation Δy n=r ny nK-y n-l n K-cy n-l n are investigated. And some sufficient conditions are obtained,which greatly improve and extend the known results.展开更多
Sufficient conditions are presented for the asymptotic behavior of all positive solutions of the multiplicative delay Logistic equation about the positive equilibrium K. The case when r(t) =r and gj(t) = t - Tj or gj(...Sufficient conditions are presented for the asymptotic behavior of all positive solutions of the multiplicative delay Logistic equation about the positive equilibrium K. The case when r(t) =r and gj(t) = t - Tj or gj(t) = [t - kj], [.] denoting the greatest integer function,where r, Tj and kj are positive constants, j = 1, 2,... m, ale also included.展开更多
A population of interacting species is considered which is governed by a system of nonlinear difference equation.In the case of the interacting species with competition,a sufficient condition for global attractivity o...A population of interacting species is considered which is governed by a system of nonlinear difference equation.In the case of the interacting species with competition,a sufficient condition for global attractivity of an equilibrium state is derived.The result can be considered as a best discrete approximation of the continuous system.展开更多
The global attractivity of the delay difference equation Deltax(n) + a(n)x(n) + f(n, Sigma(s = -k)(0)(q) over bar (s), (n) x(s + n)) = 0, which includes the discrete type of many mathematical ecological equations, was...The global attractivity of the delay difference equation Deltax(n) + a(n)x(n) + f(n, Sigma(s = -k)(0)(q) over bar (s), (n) x(s + n)) = 0, which includes the discrete type of many mathematical ecological equations, was discussed. The sufficient conditions that guarantee every solution to converge to zero are obtained. Many known results are improved and generated.展开更多
In this paper, the qualitative properties of general nonautonomous Lotka-Volterran-species competitive systems with impulsive e?ects are studied. Some new criteria on thepermanence, extinction and global attractivity...In this paper, the qualitative properties of general nonautonomous Lotka-Volterran-species competitive systems with impulsive e?ects are studied. Some new criteria on thepermanence, extinction and global attractivity of partial species are established by used themethods of inequalities estimate and Liapunov functions. As applications, nonautonomous twospecies Lotka-Volterra systems with impulses are discussed.展开更多
By using Mawhin continuation theorem,an important lemma and some analysis techniques,sufficient conditions ensuring the existence and global attractivity of positive periodic solutions for an impulsive differential eq...By using Mawhin continuation theorem,an important lemma and some analysis techniques,sufficient conditions ensuring the existence and global attractivity of positive periodic solutions for an impulsive differential equation with time varying delay are investigated.展开更多
By using a new fixed point theorem, sufficientconditions are obtained for the existence of a positivealmost-periodic solution for an discrete model of hematopoiesis with almost-periodic coefficients. Its attractivity ...By using a new fixed point theorem, sufficientconditions are obtained for the existence of a positivealmost-periodic solution for an discrete model of hematopoiesis with almost-periodic coefficients. Its attractivity and oscillation are investigated.展开更多
This paper studies the global attractivity of the positive equilibrium 1 of the delay logistic difference equation Δ y n=p ny n(1-y τ(n) ), n=0,1,2,...,(*)where {p n} is a sequence of positive real n...This paper studies the global attractivity of the positive equilibrium 1 of the delay logistic difference equation Δ y n=p ny n(1-y τ(n) ), n=0,1,2,...,(*)where {p n} is a sequence of positive real numbers, {τ(n)} is a nondecreasing sequence of integers, τ(n)<n and lim n→∞τ(n)=∞ .It is proved that ifnj=τ(n)p j≤54 for sufficiently large n and ∞j=0p j=∞,then all positive solutions of Eq.(*) tend to 1 as n→∞ .The results improve the existing results in literature.展开更多
In this paper we further study the delay differential equation N(t) = - δN(t) + pN(t -τ)e<sup>(-aN)(g-τ)</sup>,t≥0 (*)used in describing the dynamics of Nicholson’s blowflies. When p】δ, ...In this paper we further study the delay differential equation N(t) = - δN(t) + pN(t -τ)e<sup>(-aN)(g-τ)</sup>,t≥0 (*)used in describing the dynamics of Nicholson’s blowflies. When p】δ, We establish newsufficient conditions for the positive equilibrium N<sup>*</sup> of (*) which is a global attractor. Ourcriteria improve correspondent results obtained by Kulenovic, Ladas and Sficas [1], and Soand Yu [2].展开更多
Consider the discrete Lasota Wazewska modelN n+1 -N n =-μN n +pe -rN n-k , n=0,1,2,...(*)where μ∈(0,1),r,p∈(0,∞) and k ∈N.A sufficient condition for all positive solutions of (*) to...Consider the discrete Lasota Wazewska modelN n+1 -N n =-μN n +pe -rN n-k , n=0,1,2,...(*)where μ∈(0,1),r,p∈(0,∞) and k ∈N.A sufficient condition for all positive solutions of (*) to be attracted to its equilibrium N is obtained.It improves correspondent result obtained by Chen and Yu in 1999.展开更多
This paper is intended to investigate a class of Nicholson's blowflies system with patch structure and multiple pairs of distinct time-varying delays,we are interested in finding the infuence of the distinct time-...This paper is intended to investigate a class of Nicholson's blowflies system with patch structure and multiple pairs of distinct time-varying delays,we are interested in finding the infuence of the distinct time-varying delays in the same reproductive function on its asymptotic behavior.By using the theory of functional differential equations,the fluctuation lemma,and the technique of differential inequalities,some new delay-dependent criteria on the global attractivity of the positive equilibrium point are established.In addition,the effectiveness and feasibility of the theoretical achievements are illustrated by some numerical simulations.展开更多
In this paper,we analyze the global dynamics of a neoclassical growth system incorporating patch structure and multiple pairs of time-varying delays.First,we derive the global existence,positiveness and boundedness of...In this paper,we analyze the global dynamics of a neoclassical growth system incorporating patch structure and multiple pairs of time-varying delays.First,we derive the global existence,positiveness and boundedness of solutions for the addressed system.Then,by employing some novel differential inequality analyses and the fluctuation lemma,both delay-independent and delay-dependent criteria are established to ensure that all solutions are convergent to a unique positive equilibrium point vector,which does not possess the same components.Our results supplement and improve some existing results.Ultimately,some numerical examples are afforded to prove the effectiveness and feasibility of the theoretical findings.展开更多
文摘Several new sufficient conditions are given for the global attractivity of solutions of a kind of delay difference equations. They either include or improve some known results and put the study of Ladas' conjecture forward.
基金Supported by the NNSF of China(10671021)the SRF of Hunan Provincial Education Department(09C388)
文摘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.
文摘Some global properties such as global attractivity and global exponential stability for delayed Hopfield neural networks model, under the weaker assumptions on nonlinear activation functions, are concerned. By constructing suitable Liapunov function, some simpler criteria for global attractivity and global exponential stability for Hopfield continuous neural network,; with time delays are presented.
文摘In this paper the global attractivity of the nonlinear difference equationis investigated, where a,b, A ∈ (0,∞), k is an positive integer and the initial conditions x- k, …, x-1 and x0 are arbitrary positive numbers. It is shown that the unique positive equilibrium of the equation is global attractive. As a corollary, the result gives a positive confirmation on the conjecture presented by Kocic and Ladas [1,p154].
文摘In this paper, sufficient conditions are obtained for the tive steady state of the delay-logistic equation to be a global attractor.An application of the results also solves aa conjecture of Gopalsamy.
基金the Science Foundation of Educational Committee of Hunan Provinc
文摘A neutral difference equation with positive and negative coefficientsΔ(x n-c nx n-k )+p nx n-l -q nx n-r =0, n=0,1,2,...,is considered and a sufficient condition for the global attractivity of the zero solution of this equation is obtained, which improves and extends the all known results in the literature.
基金the National Natural Science Foundation of China(No.10771179)the Emphasis Subject of Guizhou Province of China
文摘We investigate a stage-structured delayed predator-prey model with impulsive stocking on prey and continuous harvesting on predator. According to the fact of biological resource management, we improve the assumption of a predator-prey model with stage structure for predator population that each individual predator has the same ability to capture prey. It is assumed that the immature and mature individuals of the predator population are divided by a fixed age, and immature predator population does not have the ability to attach prey. Sufficient conditions are obtained, which guarantee the global attractivity of predator-extinction periodic solution and the permanence of the system. Our results show that the behavior of impulsive stocking on prey plays an important role for the permanence of the system, and provide tactical basis for the biological resource management. Numerical analysis is presented to illuminate the dynamics of the system.
文摘In this paper we further study the delay differential equation N .(t)=-δN(t)+pN(t-τ)e -aN(t-τ) , t0(*) used in describing the dynamics of Nicholson’s blowflies. When p】δ ,we establish new sufficient conditions for the positive equilibrium N * of (*) which is a global attractor.
文摘The existence of positive solutions and the global attractivity of the difference equation Δy n=r ny nK-y n-l n K-cy n-l n are investigated. And some sufficient conditions are obtained,which greatly improve and extend the known results.
文摘Sufficient conditions are presented for the asymptotic behavior of all positive solutions of the multiplicative delay Logistic equation about the positive equilibrium K. The case when r(t) =r and gj(t) = t - Tj or gj(t) = [t - kj], [.] denoting the greatest integer function,where r, Tj and kj are positive constants, j = 1, 2,... m, ale also included.
文摘A population of interacting species is considered which is governed by a system of nonlinear difference equation.In the case of the interacting species with competition,a sufficient condition for global attractivity of an equilibrium state is derived.The result can be considered as a best discrete approximation of the continuous system.
文摘The global attractivity of the delay difference equation Deltax(n) + a(n)x(n) + f(n, Sigma(s = -k)(0)(q) over bar (s), (n) x(s + n)) = 0, which includes the discrete type of many mathematical ecological equations, was discussed. The sufficient conditions that guarantee every solution to converge to zero are obtained. Many known results are improved and generated.
基金Supported by The National Natural Science Foundation of P.R. China [60764003]The Scientific Research Programmes of Colleges in Xinjiang [XJEDU2007G01, XJEDU2006I05]+1 种基金The National Key Technologies R & D Program of China [2008BAI68B01]The Natural Science Foundation of Jiangxi Province [2008GZS0027]
文摘In this paper, the qualitative properties of general nonautonomous Lotka-Volterran-species competitive systems with impulsive e?ects are studied. Some new criteria on thepermanence, extinction and global attractivity of partial species are established by used themethods of inequalities estimate and Liapunov functions. As applications, nonautonomous twospecies Lotka-Volterra systems with impulses are discussed.
基金Foundation item: Supported by the Doctoral Foundation of Guilin University of Technology(01080) Supported by the National Natural Science Foundation of China(11161015, 11161011)
文摘By using Mawhin continuation theorem,an important lemma and some analysis techniques,sufficient conditions ensuring the existence and global attractivity of positive periodic solutions for an impulsive differential equation with time varying delay are investigated.
基金Supported by the NNSF of China(10541067)Supported by the NSF of Guangdong Province(10151063101000003)Supported by the Research Fund for the Doctoral Program of Higher Education(20094407110001)
文摘By using a new fixed point theorem, sufficientconditions are obtained for the existence of a positivealmost-periodic solution for an discrete model of hematopoiesis with almost-periodic coefficients. Its attractivity and oscillation are investigated.
文摘This paper studies the global attractivity of the positive equilibrium 1 of the delay logistic difference equation Δ y n=p ny n(1-y τ(n) ), n=0,1,2,...,(*)where {p n} is a sequence of positive real numbers, {τ(n)} is a nondecreasing sequence of integers, τ(n)<n and lim n→∞τ(n)=∞ .It is proved that ifnj=τ(n)p j≤54 for sufficiently large n and ∞j=0p j=∞,then all positive solutions of Eq.(*) tend to 1 as n→∞ .The results improve the existing results in literature.
基金Science Foundation of Hunan Educational Committee.
文摘In this paper we further study the delay differential equation N(t) = - δN(t) + pN(t -τ)e<sup>(-aN)(g-τ)</sup>,t≥0 (*)used in describing the dynamics of Nicholson’s blowflies. When p】δ, We establish newsufficient conditions for the positive equilibrium N<sup>*</sup> of (*) which is a global attractor. Ourcriteria improve correspondent results obtained by Kulenovic, Ladas and Sficas [1], and Soand Yu [2].
基金Supported by the Science Foundation of Educational Committee of Hunan Province
文摘Consider the discrete Lasota Wazewska modelN n+1 -N n =-μN n +pe -rN n-k , n=0,1,2,...(*)where μ∈(0,1),r,p∈(0,∞) and k ∈N.A sufficient condition for all positive solutions of (*) to be attracted to its equilibrium N is obtained.It improves correspondent result obtained by Chen and Yu in 1999.
基金This work was supposed by Jiaxing public welfare research program(2022AD30113).
文摘This paper is intended to investigate a class of Nicholson's blowflies system with patch structure and multiple pairs of distinct time-varying delays,we are interested in finding the infuence of the distinct time-varying delays in the same reproductive function on its asymptotic behavior.By using the theory of functional differential equations,the fluctuation lemma,and the technique of differential inequalities,some new delay-dependent criteria on the global attractivity of the positive equilibrium point are established.In addition,the effectiveness and feasibility of the theoretical achievements are illustrated by some numerical simulations.
文摘In this paper,we analyze the global dynamics of a neoclassical growth system incorporating patch structure and multiple pairs of time-varying delays.First,we derive the global existence,positiveness and boundedness of solutions for the addressed system.Then,by employing some novel differential inequality analyses and the fluctuation lemma,both delay-independent and delay-dependent criteria are established to ensure that all solutions are convergent to a unique positive equilibrium point vector,which does not possess the same components.Our results supplement and improve some existing results.Ultimately,some numerical examples are afforded to prove the effectiveness and feasibility of the theoretical findings.