First Author:   Yu-hsien Liao Department of Applied Mathematics, National Pingtung University of Education d9211001@ems.ndhu.edu.tw   Department of Applied Mathematics,, National Pingtung University of Education,, Pingtung 900, Taiwan. Pingtung, 900, Taiwan   +886-8-722-6141(Phone) +886-8-722-6141(Fax)