First Author:   Yu-Hsien Liao Department of Applied Mathematics, National Dong Hwa University, Hualien, Taiwan. d9211001@em92.ndhu.edu.tw   Department of Applied Mathematics,, National Dong Hwa University,, Hualien 974, Taiwan. Hualien, 974, Taiwan   +886-3-863-3512(Phone) +886-3-863-3512(Fax)