Multiplicity of positive periodic solutions to nonlinear boundary value problems with a parameter

Abstract

We study the existence and multiplicity of positive periodic solutions for second order differential equations with a parameter. In this class of problems, we are mainly concerned with the semi-positone case. Our methods are based on the nonlinear alternative principle of Leray–Schauder and Krasnosel’skii’s fixed point theorem in cones. Analytical results are illustrated by means of numerical experiments.