College of Computer;
Nanjing University of Posts and Telecommunications;
Nanjing 210023;
China;
College of Education Science and Technology;
Nanjing University of Posts and Telecommunications;
Nanjing 210023;
China;
Department of Computing;
Macquarie University;
Sydney 2109;
Australia;
College of Overseas Education;
Nanjing University of Posts and Telecommunications;
Nanjing 210023;
China Abstract;