CHEN Juan1, XU Li-sheng1, XU Meng1,ZHANG Fan2,LI Feng-ling3
(1.School of Geosciences and Info-Physics, Central South Univ, Changsha,Hunan410083,China;2. College of Mechanical and Electrical Engineering,Central South Univ,Changsha,Hunan410083,China;3. College of Automobile & Mechanical Engineering,Changsha Univ of Science & Technology,Changsha,Hunan410076,China)