Affiliation: | a Cisco School of Informatics, Guangdong University of Foreign Studies, Guangzhou 510420, China b School of Information Science and Technology, Sun Yat-sen University, Guangzhou 510275, China c School of Mathematics and Computational Science, Sun Yat-sen University, Guangzhou 510275, China d School of Information Management, Jiangxi University of Finance and Economics, Nanchang 330013, China |