基金supported by the National Natural Science Foundation of China(Grant Nos.1147116011101114)+3 种基金the National Statistical Science Research Key Program of China(Grant No.2013LZ45)the Fundamental Research Funds for the Central Universities(Grant No.30920130111015)the Jiangsu Provincial Basic Research Program(Natural Science Foundation)(Grant No.BK20131345)sponsored by Qing Lan Project
