Electronic Journal of Differential Equations, Vol. 2005(2005), No. 78, pp. 1-8. Title: Positive solutions for the beam equation under certain boundary conditions Author: Bo Yang (Kennesaw State Univ., GA, USA) Abstract: We consider a boundary-value problem for the beam equation, in which the boundary conditions mean that the beam is embedded at one end and fastened with a sliding clamp at the other end. Some priori estimates to the positive solutions for the boundary-value problem are obtained. Sufficient conditions for the existence and nonexistence of positive solutions for the boundary-value problem are established. Submitted April 29, 2005. Published July 8, 2005. Math Subject Classifications: 34B18. Key Words: Fixed point theorem; cone; nonlinear boundary-value problem; positive solution.