1. Information Engineering College, Xinjiang Institute of Engineering,Urumqi,China,830023
2. School of Computing, Ulster University,Belfast,UK,BT15 1ED
3. School of Computer and Communication Engineering, University of Science and Technology Beijing,Beijing,China,100083
4. University of Cagliari,Department of Electrical and Electronic Engineering,Sardinia,Italy,09124
5. School of Computer Science, University College Dublin,Dublin,Ireland,D04 V1W8