The article is concerned with the existence of positive solutions of the delay differential equations. The asymptotic properties of solutions are also treated.

and Applied Analysis 3 We now define two maps S1 and S2 : Ω → C t0,∞ , R as follows: S1x t ⎧⎨ ⎩ a t x t − τ , t ≥ t1, S1x t1 , t0 ≤ t ≤ t1, S2x t ⎪⎨ ⎪⎩ − 1 n − 1 ! ∫∞ t s − t n−1p s f x s − σ ds, t ≥… (More)

In this paper we particularly draw attention to the existence of solutions which describe the maturation rates of an age-structured insect population model. Such models commonly divide the population… (More)

where the functions p, τ ∈ C([t0,∞), (0,∞)), τ (t) is nondecreasing, τ (t) < t for t ≥ t0 and limt→∞ τ (t) =∞. Our aim is to establish new sufficient conditions for the oscillation of all solutions… (More)