Center for General Education, Chang Gung University, Kwei-Shan, Tao-Yuan 333, Taiwan
Copyright © 2010 Tsing-San Hsu. 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 study the existence and multiplicity of positive solutions
for the following Dirichlet equations: in , on , where , ( if ; if ), is a smooth unbounded domain in , , and satisfy suitable conditions, and maybe change sign in .