Sponsored by research fund project of Nanjing institute of technology ( CKJB201201);the Support Peoject of Science and Technology of Jiangsu Province ( BE2011712);the Planning Project of Humanities and Social Science Research Fund of the Ministry of Education ( 12YJAZH151);the College Fund Project of Jiangsu Province ( 10KJB460003);the Youth Project of Humanities and Social Science Research Fund of Theministry of Education ( 12YJCZH209)