Copyright © 2011 Jingjing Cai and Guilong Liu. 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.
Using a specially constructed cone and the fixed point index theory, this work shows existence and
nonexistence results of positive solutions for fourth-order boundary value problem with two different parameters in Banach spaces.