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排序方式: 共有245条查询结果,搜索用时 250 毫秒
1.
In this paper, the Leslie predator-prey system with two delays is studied. The stability of the positive equilibrium is discussed by analyzing the associated characteristic transcendental equation. The direction and stability of the bifurcating periodic solutions are determined by applying the center manifold theorem and normal form theory. The conditions to guarantee the global existence of periodic solutions are given. 相似文献
2.
具有时滞的非自治的捕食-食饵系统的全局吸引 总被引:1,自引:0,他引:1
考虑一个具有离散时滞的非自治的捕食—食饵系统。系统是由3种群组成的,其中一个为捕食者,另两个为食饵种群。本文的目的是给出时滞对系统的持续生存是无害的,从而确定了系统的周期解全局吸引的条件。 相似文献
3.
研究捕食者具有非单调功能反应和周期脉冲扰动的捕食者一食饵系统,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,通过数值模拟阐明系统在周期脉冲扰动下的复杂性. 相似文献
4.
PERSISTENCE AND GLOBAL STABILITY FOR TWO-SPECIES NONAUTONOMOUS PREDATOR-PREY SYSTEM WITH DIFFUSION AND TIME DELAY 总被引:3,自引:0,他引:3
In this paper, a non-autonomous predator-prey model with diffusion andcontinuous time delay is studied, where the prey can diffuse between two pat-ches of a heterogeneous environment with barriers between patches, but for thepredator, the diffusion does not involve a barrier between patches, further itis assumed that all the parameters are time-dependent. It is shown that thesystem can be made persistent under some appropriate conditions. Moreover,sufficient conditions that guarantee the existence of a unique periodic solutionwhich is globally asymptotic stable are derived. 相似文献
5.
Asymptotic Behavior of a Stochastic Predator-prey Model with Beddington-DeAngelis Functional Response and L\'{e}vy Jumps 下载免费PDF全文
A stochastic two-prey-one-predator model with Beddington-DeAngelis functional response and L\''{e}vy jumps is proposed and investigated in this paper. First of all, we prove the existence and uniqueness of the global positive solution, and stochastic ultimate boundedness of the solution. Next, under a simple assumption, by using It\^{o} formula and other important inequalities, some sufficient conditions are established to ensure the extinction and persistence in the mean of the system. The results show that neither strong white noise nor L\''{e}vy noise is conducive to the persistence of the population. Finally, the theoretical results are verified by numerical simulations. 相似文献
6.
In this paper, we consider a predator-prey system with stage structure and harvesting (where the predator population has two stages, an immature stage and a mature stage with harvesting, and the growth of the prey population is of Lotka-Volterra nature). We obtain the conditions of the globally asymptotic stability for three nonne-gative equilibria of this system. 相似文献
7.
Sufficient conditions are established for the permanence in a delayed discrete predator-prey model with Holling type III functional response:
8.
时间测度上具有时滞基于半比率的捕食者-食饵扩散系统的周期解 总被引:1,自引:0,他引:1
刘振杰 《数学的实践与认识》2008,38(24)
在时间测度上研究一类具有时滞和基于半比率且有功能性反应的两种群捕食者-食饵扩散系统,利用Mawhin重合度理论建立了这类系统的周期解存在的一个充分性判据.从而使这一类系统的连续与离散情形即相应的微分方程和差分方程的周期解存在性问题得到了统一研究. 相似文献
9.
黄永年 《宁波大学学报(理工版)》2000,13(4):5-10
分析了连续时间和离散时间的捕食-被捕食模型:Hassel and Rogers的狼与鹿相互作用的模型,发现它们的轨线有一定程度的相似,但从生态意义上讲,离散模型更合适。 相似文献
10.
A kind of predator-prey system of Holling typeⅡand interaction perturbation with impulsive effect is presented.By using Floquet theory and small amplitude perturbations skills,the locally asymptotical stability of prey-eradication periodic solution and the permanence of the system are discussed and the corresponding threshold conditions are given respectively.Finally,the existence of positive periodic solution is investigated by the bifurcation theory. 相似文献