1. School of Ocean Information Engineering, Jimei University, Xiamen 361021, P. R. China
2. Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung 811, Taiwan
3. Department of Aeronautical Engineering, Chaoyang University of Technology, Taichung 413, Taiwan
4. Department of Applied Materials and Optoelectronic Engineering, Nantou County 545, National Chi Nan University, Taiwan