脉冲泛函微分方程三个正周期解的存在性(英文)

Existence of Three Positive Periodic Solutions to Functional Differential Equations with Impulses

用锥不动点定理,建立了形如{y′(t)=-a(t)y(t)+g(t,y(t-τ(t)))t≠tj y(tj+)=y(tj-)+Ij(y(tj))j∈Z的脉冲泛函微分方程3个正周期解存在的充分条件,其中,a∈C(R,R+),τ∈C(R,R),g∈C(R×[0,∞),[0,∞)),a,τ,g是ω-周期函数.

By using a fixed point theorem in cones,some sufficient conditions are established for the existence of three positive periodic solutions for a kind of nonautonomous functional differential equations with impulses and delays of the form {y′（t）=-a（t）y（t）＋g（t,y（t-τ（t）））t≠tj y（t＋j）=y（t-j）＋Ij（y（tj））j∈Zwhere a∈C（R,R＋）,τ∈C（R,R）,g∈C（R×[0,∞）,[0,∞））,and a,τ,g are ω-periodic functions,and ω0 is a constant.