Guodong Ye1, Kaixin Jiao1, Xiaoling Huang2, Bok-Min Goi3, Wun-She Yap3. 1. Faculty of Mathematics and Computer Science, Guangdong Ocean University, Zhanjiang, 524088, China. 2. Faculty of Mathematics and Computer Science, Guangdong Ocean University, Zhanjiang, 524088, China. xyxhuang@hotmail.com. 3. Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Sungai Long, 43000, Cheras, Selangor, Malaysia.