1. College of Automation Engineering; Nanjing University of Aeronautics and Astronautics; Nanjing 210016, Jiangsu China
2. School of Science; Huaihai Institute of Technology; 59 Cangwu Road Lianyungang 222005, Jiangsu China
3. Department of Computing and Mathematical Sciences; University of Glamorgan; Pontypridd CF37 1DL UK
4. School of Engineering and Science; Victoria University; Melbourne 8001 Vic Australia
5. School of Electrical and Electronic Engineering; The University of Adelaide; Adelaide SA 5005 Australia
6. Department of Engineering Faculty of Engineering and Science; University of Agder; N-4898 Grimstad Norway