In this paper,by making use of the calculous technique and some results of the impulsive differential inequality,oscillatory properties of the solutions of certain nonlinear impulsive delay hyperbolic partial differen...In this paper,by making use of the calculous technique and some results of the impulsive differential inequality,oscillatory properties of the solutions of certain nonlinear impulsive delay hyperbolic partial differential equations with nonlinear diffusion coefficient are investigated.Sufficient conditions for oscillations of such equations are obtained.展开更多
Consider the nonautonomous delay logistic equation △yn=pnyn(1-yn-ln/k),n≥0, where {Pn}n≥0 is a sequence of nonnegative real numbers, {In}n≥0 is a sequence of positive integers satisfying n→∞lim(n-ln)=∞, and...Consider the nonautonomous delay logistic equation △yn=pnyn(1-yn-ln/k),n≥0, where {Pn}n≥0 is a sequence of nonnegative real numbers, {In}n≥0 is a sequence of positive integers satisfying n→∞lim(n-ln)=∞, and k is a positive constant. Only solutions which are positive for n ≥ 0 are considered. We obtain a new sufficient for all positive solutions of (1) to oscillate about k which contains the corresponding result in [2] when i = 1.展开更多
Based on the Chay-Keizer model with three time scales, we investigate the role of the slowest variable in generating bursting oscillations in pancreaticcells. It is shown that both of the two slow processes can intera...Based on the Chay-Keizer model with three time scales, we investigate the role of the slowest variable in generating bursting oscillations in pancreaticcells. It is shown that both of the two slow processes can interact to drive fast, medium and slow bursting oscillations typically observed in pancreaticcells. Moreover, diverse patterns of electrical bursting are presented, including the "fold/fold" bursting, "fold/homoclinic" bursting, "fold/Hopf" bursting via "fold/fold" hysteresis loop, and the "fold/fold" bursting via point-point hysteresis loop. Fast-slow dynamics is used to analyze the types and generation mechanisms of these bursting oscillations. The results can be instructive for understanding the role of the slow variables and the current conductance in pancreaticcells activities.展开更多
In this paper, we consider a Cohen-Grossberg neural network with three delays. Regard- ing time delays as a parameter, we investigate the effect of time delays on its dynamics. We show that there exist stability switc...In this paper, we consider a Cohen-Grossberg neural network with three delays. Regard- ing time delays as a parameter, we investigate the effect of time delays on its dynamics. We show that there exist stability switches for time delays under certain conditions and the conditions for the existence of periodic oscillations are given by discussing the associated characteristic equation. Numerical simulations are given to illustrate the obtained results and interesting network behaviors are observed, such as multiple stability switches of the network equilibrium and synchronous (asynchronous) oscillations.展开更多
基金Supported by the Natural Science Foundation of China(10471086)Supported by the Science Research Foundation of Department of Education of Hunan Province(07C164)
文摘In this paper,by making use of the calculous technique and some results of the impulsive differential inequality,oscillatory properties of the solutions of certain nonlinear impulsive delay hyperbolic partial differential equations with nonlinear diffusion coefficient are investigated.Sufficient conditions for oscillations of such equations are obtained.
文摘Consider the nonautonomous delay logistic equation △yn=pnyn(1-yn-ln/k),n≥0, where {Pn}n≥0 is a sequence of nonnegative real numbers, {In}n≥0 is a sequence of positive integers satisfying n→∞lim(n-ln)=∞, and k is a positive constant. Only solutions which are positive for n ≥ 0 are considered. We obtain a new sufficient for all positive solutions of (1) to oscillate about k which contains the corresponding result in [2] when i = 1.
基金supported by the National Naturual Science Foundation of China (Grant Nos. 10872014, 10972001, 10832006, 10702002 and 10972018)
文摘Based on the Chay-Keizer model with three time scales, we investigate the role of the slowest variable in generating bursting oscillations in pancreaticcells. It is shown that both of the two slow processes can interact to drive fast, medium and slow bursting oscillations typically observed in pancreaticcells. Moreover, diverse patterns of electrical bursting are presented, including the "fold/fold" bursting, "fold/homoclinic" bursting, "fold/Hopf" bursting via "fold/fold" hysteresis loop, and the "fold/fold" bursting via point-point hysteresis loop. Fast-slow dynamics is used to analyze the types and generation mechanisms of these bursting oscillations. The results can be instructive for understanding the role of the slow variables and the current conductance in pancreaticcells activities.
文摘In this paper, we consider a Cohen-Grossberg neural network with three delays. Regard- ing time delays as a parameter, we investigate the effect of time delays on its dynamics. We show that there exist stability switches for time delays under certain conditions and the conditions for the existence of periodic oscillations are given by discussing the associated characteristic equation. Numerical simulations are given to illustrate the obtained results and interesting network behaviors are observed, such as multiple stability switches of the network equilibrium and synchronous (asynchronous) oscillations.