Existence of positive periodic solution of an impulsive delay Logistic model

In this paper, we use the continuation theory for k-set contractions to study the existence of positive periodic solutions of the impulsive delay Logistic modelx′(t)=r(t)x(t)1-x(t-τ)K(t),t≠tk,x(tk+)-x(tk)=bkx(tk),k=1,2,…The sufficient conditions of the existence of positive periodic solution are obtained.