Existence of positive almost periodic or ergodic solutions for some neutral nonlinear integral equations

Abstract

We state sufficient conditions for the existence of the positive, almost periodic or ergodic solutions of the following neutral integral equation: \begin{equation*} x(t)=\gamma x(t-\sigma )+(1-\gamma )\displaystyle\int_{t-\sigma }^{t}f(s,x(s))ds, \end{equation*} where $0\leq \gamma < 1$ and $f:\mathbb R\times \mathbb R^{+}\rightarrow \mathbb{R} ^{+}$ is a continuous map. We also treat the asymptotically, weakly and pseudo almost periodic solutions. Our results do not need the monotonicity of $f(t,.)$.