【摘要】 研究了一类具有功能性反应(Holling-Ⅱ)的时滞捕食系统。利用重合度理论证明并得到了系统正周期解存在性的充分条件。更多还原

【Abstract】 This paper investigates a three species of predator-prey chains models with a delay of time and the Holling-Ⅱ functional response.By using Gains and Mawhins continuation theorem of coincidence degree theory,a set of easily verifiable sufficient conditions are obtained to guarantee the existence of positive periodic solutions of the system.更多还原