Open Access Research Article

Existence of Positive Solutions of Nonlinear Second-Order Periodic Boundary Value Problems

Ruyun Ma*, Chenghua Gao and Ruipeng Chen

Author Affiliations

Department of Mathematics, Northwest Normal University, Lanzhou 730070, China

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Boundary Value Problems 2010, 2010:626054  doi:10.1155/2010/626054

Published: 25 November 2010

Abstract

This paper is devoted to study the existence of periodic solutions of the second-order equation , where is a Carathéodory function, by combining a new expression of Green's function together with Dancer's global bifurcation theorem. Our main results are sharp and improve the main results by Torres (2003).