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81.
82.
一类具有垂直传染与脉冲免疫的SEIR传染病模型的全局分析 总被引:2,自引:0,他引:2
考虑了一个具有垂直传染与积分时滞的SEIR传染病动力学模型.分析了该模型在脉冲免疫接种条件下的动力学行为,获得了传染病灭绝的充分条件,进而运用脉冲时滞泛函微分方程理论,获得了含有时滞的系统持久性的充分条件,并且证明了积分时滞与脉冲免疫能对模型的动力学行为产生显著的影响. 相似文献
83.
研究一类害虫管理SI传染病模型,考虑脉冲投放病虫和人工捕杀相结合,得到系统的灭绝周期解,给出此周期解的全局吸引性,并获得了系统一致持续生存的条件.给出了害虫管理综合防治策略. 相似文献
84.
研究一类具有连续投放和脉冲控制的害虫管理SI数学模型,证明了连续投放系统正平衡点的全局渐近稳定性,讨论了脉冲控制系统的持续性,并对所得结论进行了数值模拟. 相似文献
85.
利用重合度理论中的延拓定理,获得了一类具有脉冲效应和单调功能反应的时滞捕食系统正周期解存在性的充分条件.最后,通过列举三个例子表示我们等待结果的有效性. 相似文献
86.
In this paper, some theorems of uniform stability and uniform asymptotic stability for impulsive functional differential equations with infinite delay are proved by using Lyapunov functionals and Razumikhin techniques. An example is also proved at the end to illustrate the application of the obtained results. 相似文献
87.
In this work, we consider a pest management SI model with concerns about releasing of infective pests and spraying pesticides at different fixed moments. We prove that all solutions the investigated system are uniformly ultimately bounded, and there exists globally asymptotic stable pest‐extinction boundary periodic solution when certain condition is satisfied. Furthermore, the permanent condition of the system is also obtained. It is concluded that the approach, which combines releasing infective pests with spraying pesticides in different fixed moments, provides reliable tactic basis for the practical pest management. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
88.
In this paper, a non‐autonomous SIRVS epidemic model with time delay and vaccination is investigated. We assume that the vaccinated have a constant immunity period. Some new threshold conditions are obtained. These threshold conditions govern the extinction and permanence of the disease. When the model degenerates into the periodic or autonomous case, the corresponding basic reproduction number can be derived from these threshold conditions. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
89.
In this paper, we study the existence and asymptotic stability in the p-th moment of mild solutions of nonlinear impulsive stochastic partial functional integrodifferential equations with delays. We suppose that the linear part possesses a resolvent operator in the sense given in Grimmer [R. Grimmer, Resolvent operators for integral equations in a Banach space, Trans. Am. Math. Soc. 273(1) (1982), 333–349] and the nonlinear terms are assumed to be Lipschitz continuous. A fixed point approach is employed for achieving the required result. An example is provided to illustrate the results of this work. 相似文献
90.
F. Córdova-Lepe E. González-Olivares M. Pinto 《Journal of Difference Equations and Applications》2013,19(5):721-735
The dynamics of four source–sink models for an exploited resource under a constant fishing effort are here presented. Two models are described by ordinary differential equations; the other two are expressed by impulsive differential equations systems. A continuous time growth function for the resource is assumed for each of the four model. The impulsiveness in the harvest activity among fixed seasonal closures were considered in the models expressed by impulsive differential equations. We note that all our models show the possibility of getting a sustainable resource exploitation. The results obtained using both techniques are compared. These metapopulation models suggest the convenience of considering the source patches as marine reserves, in order to preserve the renewable resources. 相似文献