%0 Journal Article
%T Positive periodic solutions of singular systems
%A Haiyan Wang
%J Mathematics
%D 2010
%I arXiv
%R 10.1016/j.jde.2010.08.027
%X The existence and multiplicity of positive periodic solutions for second order non-autonomous singular dynamical systems are established with superlinearity or sublinearity assumptions at infinity for an appropriately chosen parameter. Our results provide a unified treatment for the problem and significantly improve several results in the literature. The proof of our results is based on the Krasnoselskii fixed point theorem in a cone.
%U http://arxiv.org/abs/1007.3302v1