Existence of multiple positive periodic solutions of delayed predator-prey models with functional responses
In this paper, by applying the continuation theorem of coincidence degree theory, we establish some new criteria for the existence of multiple positive periodic solutions for the delayed predator-prey model x'(t) = x(t) (r(t) - a(t)x(t)) - b(t)f (x(t)) y(t), y'(t) = y(t) (c(t)f (x(t - tau)) - d(t)), when functional response function f is monotonic or nonmonotonic. (c) 2006 Elsevier Ltd. All rights reserved.
positive periodic solution delay predator-prey model coincidence degree monotonic nonmonotonic