Affiliation: | 1.School of Information Science, Guangdong University of Finance and Economics, Guangzhou 510320, China;2.School of Mathematics, Georgia Institute of Technology, Atlanta, GA 30332, U.S.A.;3.Guangdong Province Key Laboratory of Computational Science, Guangzhou 510275, China;4.School of Mathematics, Sun Yat-sen University, Guangzhou 510275, China |