jgg     2010 30 (5):  135-139    ISSN: 0412-1961  CN: 21-1139/TG QUALITY ANALYSIS OF GNSS DATA BASED ON TEQC IN DIFFERENT ENVIRONMENTS Yang Zhe 1) ; Dai Wujiao 1,2) ; Yu Wenkun 1,2) ; and Liao Jianping 1) 1)Department of Surveying Engineering & Geo- Informatics, Central South University, Changsha 4100832)Key Lab. Of Precise Engineering Surveying & Deformation Disaster Monitoring of Hunan Province, Changsha 410083 Received: 1900-01-01  Revised: 1900-01-01  Online: null Supporting info null