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1.
基于害虫的生物控制和化学控制策略,考虑到化学杀虫剂对天敌的影响,利用脉冲微分方程建立了在不同的固定时刻分别喷洒杀虫剂和释放天敌的具有时滞的第III功能反应的捕食者-食饵脉冲动力系统.证明了当脉冲周期小于某个临界值时,系统存在一个渐进稳定的害虫灭绝周期解,否则系统持续生存.并用Matlab软件对害虫灭绝周期解及害虫周期爆发现象进行了数值模拟.  相似文献   

2.
具有脉冲效应和综合害虫控制的捕食系统   总被引:8,自引:1,他引:7  
本文通过生物控制和化学控制提出了具有周期脉冲效应与害虫控制的捕食系统. 系统保护天敌避免灭绝,在一些条件下可以使害虫灭绝.就是说当脉冲周期小于某一临界值时,存在全局稳定害虫灭绝周期解.脉冲周期增大大于临界值时,平凡害虫灭绝周期解失去稳定性并产生正周期解,利用分支理论来研究正周期解的存在性.进而,利用李雅普诺夫函数和比较定理确定了持续生存的条件.  相似文献   

3.
基于综合害虫管理,提出并研究了一类具有脉冲效应和Holling Ⅱ类功能反应的两个捕食者一个食饵系统.利用脉冲微分方程的Floquet理论和比较定理,得到了系统灭绝和持续生存的充分条件.最后,简要讨论了该综合害虫管理策略的有效性及系统在周期脉冲扰动下的动力复杂性.  相似文献   

4.
魏春金  陈兰荪 《数学研究》2008,41(4):393-400
本文考虑了一类食饵具有流行病和阶段结构的脉冲时滞捕食模型.利用脉冲时滞微分方程的相关理论和方法,获得易感害虫根除周期解全局吸引的充分条件以及当脉冲周期在一定范围内时,天敌与易感害虫可以共存且易感害虫的密度可以控制在经济危害水平E(EIL)之下.我们的结论为现实的害虫管理提供了可靠的策略依据.  相似文献   

5.
本文研究一类捕食者具有阶段结构和食饵具有群体防卫作用的脉冲控制系统,应用Floquet乘子理论和脉冲比较定理,获得食饵(害虫)灭绝周期解局部稳定和系统持续生存的充分条件,并通过数值例子揭示了系统诸如高倍周期振荡,混沌,吸引子突变,倍周期与半周期分支等复杂的动力学现象.讨论脉冲周期,成年食饵的投放量和群体防卫效应系数对系统的重要作用,得出的结论为实际的害虫管理提供了可靠的策略依据.  相似文献   

6.
讨论了与害虫治理相关的一类捕食者具脉冲扰动与食饵具有化学控制的阶段结构时滞捕食-食饵模型,得到了害虫灭绝周期解的全局吸引和系统持久的充分条件,也证明了系统的所有解的一致完全有界.得出的结论为现实的害虫治理提供了可靠的策略依据.  相似文献   

7.
非线性脉冲状态依赖捕食-被捕食模型的定性分析   总被引:1,自引:1,他引:0  
由于资源的有限性以及害虫群体对杀虫剂的抗性发展等因素,使得杀虫剂对害虫的杀死率具有饱和效应.因此,当害虫的数量达到经济阈值时, 杀虫剂对害虫的杀死率与经济阈值有关.为了刻画上述饱和效应,建立了一类非线性脉冲状态依赖捕食被捕食模型.利用Lambert W函数和脉冲半动力系统的相关技巧,分析了模型阶1正周期解的存在性和稳定性, 得到了相应的充分条件.进而讨论了非线性脉冲与线性脉冲对阶1周期解存在性的影响.  相似文献   

8.
研究一类状态依赖脉冲控制的害虫管理数学模型,当害虫的数量达到一定的临界值时,通过释放天敌和喷洒农药使得害虫的数量不超过经济危害水平.首先利用几何分析和后继函数方法得到了系统阶1周期解的存在性,进而运用类Poincare准则证明系统阶1周期解是轨道渐近稳定的.结论表明在一定的条件下,总能将害虫控制在经济危害水平以内,从而人们在农业生产过程中能够获得最大收益.证明系统存在阶1周期解的方法可推广到其它状态依赖脉冲反馈模型中.  相似文献   

9.
具有密度依赖的生育脉冲单种群阶段结构模型   总被引:1,自引:0,他引:1  
给出具有密度依赖生育脉冲单种群阶段结构数学模型.通过研究其频闪映射所确定的离散动力系统,获得了具有生育脉冲的系统存在周期解及其稳定的阈值,当系统的参数超过阈值,存在一系列的分支并最终走向混沌,这说明生育脉冲使系统动力学行为变得非常复杂,提供了一个自然的周期,而使系统从倍周期分支到混沌.  相似文献   

10.
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   

11.
Lur''''e系统稳定与同步的脉冲控制   总被引:2,自引:0,他引:2  
提出了Lur’e系统的脉冲控制系统,利用关于脉冲系统稳定的几个定理,得到了具变化的脉冲区间的Lur'e系统镇定的充分条件;并且给出了Lur'e系统的适当参数与脉冲控制律,使得两个Lur'e系统脉冲同步。最后,给出数值例子说明本结论的有效性。  相似文献   

12.
In this paper, we study optimal relaxed controls and relaxation of nonlinear fractional impulsive evolution equations. Firstly, existence of piecewise continuous mild solutions for the original fractional impulsive control system is presented. Secondly, fractional impulsive relaxed control system is constructed by using a regular countably additive measure and making the original control system convexified. Thirdly, optimal relaxed controls and relaxation theorems are obtained. Finally, application to initial-boundary value problem of fractional impulsive parabolic control system is considered.  相似文献   

13.
The issue of impulsive control theory for the synchronization of the nuclear spin generator (NSG) chaotic systems is developed. We propose an impulsive control scheme for the complete synchronization of the NSG system including chaotic systems. A sufficient condition for the impulsive control is derived, with an easily calculated maximum impulsive interval. The proposed impulsive control scheme is applied to the NSG system and the simulation result demonstrates the effectiveness of the method.  相似文献   

14.
This paper studies the stability problem of two-time-scale system via event-triggered impulsive control and self-triggered impulsive control. The overall system is modeled with the hybrid formalism. Two Chang transformations are introduced to completely decouple the hybrid system states into flow set and jump set. A composite impulsive controller based on slow and fast system states is proposed, under which the slow and fast subsystems are simultaneously triggered by event-triggered and self-triggered mechanism, respectively. As a result, the stability conditions are derived for the system under event-triggered and self-triggered impulsive control, respectively. Furthermore, the theoretical result of self-triggered impulsive control is applied to the consensus of the interconnected two-time-scale systems. Finally, simulation examples and comparison study show the effectiveness of the proposed control strategies.  相似文献   

15.
In this paper, we investigate the dynamic behavior of an eco-epidemic model with impulsive control strategy. By using Floquet theorem of impulsive differential equation, we show there is a globally stable prey eradication periodic solution when the impulsive period is less than some critical value. We study the permanence of the system. Numerical simulations show that the complex dynamics of the system depends on the values of impulsive period and impulsive perturbation, for example double period, triple period solutions.  相似文献   

16.
An impulsive SI model with Monod-Haldane functional response for pest control is proposed and investigated. First, we have proved that there exists an asymptotically stable pest-eradication periodic solution when the impulsive period is less than some critical value. Otherwise, the above system can be permanent. Then, influences of impulsive perturbation including impulse period, the time of spraying pesticide and the quantity of releasing infective pests on the above system have been studied. Moreover, numerical simulations show that the system has rich dynamical behaviors. Finally, it is concluded that the approach of combining impulsive infective releasing with impulsive pesticide spraying is more effective than the classical one if the chemical control is adopted rationally.  相似文献   

17.
建立一个具有脉冲效应的非自治随机的比例依赖的捕食-食饵模型,通过研究具有脉冲效应的非自治随机系统与无脉冲效应的非自治随机系统的等价性,证明该模型的有界性,均值一致有界和灭绝性等动力学性质.  相似文献   

18.
A kind of predator–prey system with distributed time delay and impulsive harvest is firstly presented and then the effects of impulsive harvest on the system are discussed by means of chain transform. By using the Floquet’s theory and the comparison theorem of impulsive differential equation, the thresholds between permanence and extinction of each species are obtained as functions of model parameters. It is proved that the impulsive period and the proportion of the impulsive harvest will ultimately affect the fate of each species. Finally, the theoretical results obtained in this paper are confirmed by numerical simulations.  相似文献   

19.
A stage-structured predator-prey system with impulsive effect and Holling type-II functional response is investigated. By the Floquet theory and small amplitude perturbation skills, it is proved that there exists a global stable pest-eradication periodic solution when the impulsive period is less than some critical values. Farther, the conditions for the permanence of system are established. Numerical simulations are carried out to illustrate the impulsive effect on the dynamics of the system.  相似文献   

20.
针对微生物批式流加发酵生产1,3-丙二醇的非线性脉冲系统,建立敏感参数的优化辨识模型(PDP),论述了模型解的性质、解与参量的关系以及辨识问题最优解的存在性.通过构造算法求得辨识问题最优解,并讨论了新参数下脉冲系统解的稳定性.  相似文献   

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