About author:LI Ri-song(1968-), male, native of Zhanjiang, Guangdong, an associate professor of Guangdong Ocean University, engages in topological dynamics.
Supported by:
Supported by the NSF of Guangdong Province(10452408801004217); Supported by the Key Scientific and Technological Research Project of Science and Technology Department of Zhanjiang City(2010C3112005);