jgg     2010 30 (6):  126-130    ISSN: 0412-1961  CN: 21-1139/TG STUDY ON GREY MARKOV PREDICTION MODEL FOR OLD GOAF RESIDUAL SUBSIDENCE Wang Zhengshuai 1,2) ;and Deng Kazhong 1,2) 1Jiangsu Key Laboratory of Resources and Environmental Information Engineering,CUMT, Xuzhou 2211162School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116 Received: 1900-01-01  Revised: 1900-01-01  Online: null Supporting info null