摘要
【目的】为了研究随机恒化器模型的渐近行为,本文考虑恒化器中一类稀释率受到白噪声干扰,具有Michaelis-Menten食物链的随机模型。首先证明模型正解的全局存在唯一性;【方法】然后通过构造Lyapunov函数,利用伊藤公式,得到模型的绝灭平衡点随机全局渐近稳定的充分条件;【结果】最后研究模型解的长期渐近行为,主要揭示在不同随机噪声条件下模型的解围绕其相应确定性模型的无捕食者平衡点和正平衡点的振荡行为。【结论】结果改进和推广现有文献的相关工作。
[Purposes]To investigate the asymptotic behaviors of a stochastic chemostat model with Michaelis-Menten food chain in which the dilution rate is disturbed by white noise.First,the global existence and uniqueness of the positive solution of the model is proved.[Methods]Then,by constructing Lyapunov function and using It's formula,the sufficient condition for the stochastic global asymptotic stability of the washout equilibrium of the model is obtained.[Findings]Finally,the long-time asymptotic behaviors of the solution of the model are studied,which mainly reveals the oscillatory behavior of the solution around the predator-free equilibrium and positive equilibrium of the corresponding deterministic model under different conditions.[Conclusions]The results improve and extend the relevant work of the existing literature.
引文
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