APPML
2005
13 years 4 months ago
2005
In this paper, we discuss the existence of positive periodic solutions to the nonlinear differential equation u (t) + a(t)u(t) = f (t, u(t)), t R, where a : R [0, +) is an -peri...
APPML
2010
13 years 4 months ago
2010
In this paper, we apply a fixed point theorem to obtain sufficient conditions for the existence of positive periodic solutions for two classes of higher-order functional differenc...