至少存在两个正周期解的传染病模型

Existence of Two Periodic Solutions of An Epidemic Model

讨论了传染率为周期函数、具有非线性传染项和常数治愈率S-I-R传染病模型.通过构造同伦函数,应用重合度理论和Mawhin连续性定理,证明了该模型至少存在两个正周期解.

An epidemic model with the periodic infectious parameter,nonlinear incidence and constant recover rate is discussed.The existence of two periodic solutions of the S-I-R models is proved by using the coincidence degree theorem,Mawhin＇s continuous theorem,and homotopy functions.