Boundary Value Problems 
Volume 2008 (2008), Article ID 197205, 21 pages
doi:10.1155/2008/197205
Research Article

Multiplicity Results via Topological Degree for Impulsive Boundary Value Problems under Non-Well-Ordered Upper and Lower Solution Conditions

Xu Xian,1 Donal O'Regan,2 and R. P. Agarwal3

 1Department of Mathematics, Xuzhou Normal University, Xuzhou, Jiangsu 221116, China
2Department of Mathematics, National University of Ireland, Galway, Ireland
3Department of Mathematical Science, Florida Institute of Technology, Melbourne, FL 32901, USA
Received 14 April 2008; Accepted 26 August 2008

Recommended by R. P. Gilbert

Abstract

Some multiplicity results for solutions of an impulsive boundary value problem are obtained under the condition of non-well-ordered upper and lower solutions. The main ideas of this paper are to associate a Leray-Schauder degree with the lower or upper solution.