jgg     2010 30 (6):  112-115    ISSN: 0412-1961  CN: 21-1139/TG ANALYSIS OF INFLUENCE OF SAMPLING INTERVAL AND VTECMODEL ON ESTIMATION OF GPS INSTRUMENTAL BIASES Gao Shuzhao ;and Huang Dingfa School of Civil Engineering, Southwest Jiaotong University, Chengdu 610031 Received: 1900-01-01  Revised: 1900-01-01  Online: null Supporting info null