【摘要】 研究了一类食饵具有S-型变收获率和单调功能反应的中立型捕食系统.通过利用一些新的分析技巧和重合度理论中的延拓定理,获得了其正周期解存在性的充分条件,推广和改进已有文献的相关结果.更多还原

【Abstract】 This paper investigates the existence of positive periodic solutions for a kind of neutral predator-prey system with an 5-type variable harvesting in the prey species.By using some new technique of analysis and a continuation theorem based on coincidence degree theory,some new sufficient conditions of positive periodic solutions of the system are established.The criteria extend and improve some earlier results.更多还原