Zhanping Liang

Learn More
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 ω-periodic continuous function with a(t) ≡ 0, f : R × [0, +∞) → [0, +∞) is continuous and f (·, u) : R → [0, +∞) is also an ω-periodic function for each u ∈ [0, +∞). Using the fixed(More)
  • 1