supported in part by the Natural Science Foundation of Jiangsu Province of China(Grant No.BK20151459);the National Natural Science Foundation of China(Grant Nos.11526112; 11771343);the Science and Technology Planning Project of Jiangxi Provincial Education Department(Grant No.GJJ150401);the Open Issue of Financial Engineering Key Laboratory of Jiangsu Province of China(Grant No.NSK2015-17)
partly supported by the Project of the Humanities and Social Sciences of the Ministry of Education to the West and the Border Areas(Grant No.14XJC910001);the Fundamental Research Funds for the Central Universities(Grant No.106112016CDJXY100002);the National Natural Science Foundation of China(Grant No.11671404)