Existence of positive periodic solutions of neutral nonlinear differential systems with variable delays
OMA-Vol. 3 (2019), Issue 2, pp. 19 – 31 Open Access Full-Text PDF
Hocine Gabsi, Abdelouaheb Ardjouni, Ahcene Djoudi
Abstract: By using some mixed techniques of the Mawhin coincidence degree theory and the Krasnoselskii fixed point theorem, we obtained the existence of positive periodic solutions of the neutral nonlinear differential system. Also, sufficient conditions for the existence of positive periodic solutions to the system with feedback control are given. Our results substantially extend and improve existing results.