Boundary Value Problems
Volume 2008 (2008), Article ID 574842, 9 pages
Research Article

Multiplicity of Positive Periodic Solutions of Singular Semipositone Third-Order Boundary Value Problems

Yigang Sun

Department of Applied Mathematics, Hohai University, Nanjing 210098, China

Received 2 July 2007; Accepted 13 December 2007

Academic Editor: Colin Rogers

Copyright © 2008 Yigang Sun. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


We establish the existence of multiple positive solutions for a singular nonlinear third-order periodic boundary value problem. We are mainly interested in the semipositone case. The proof relies on a nonlinear alternative principle of Leray-Schauder, together with a truncation technique.