Supported by the National 863 Program of China (No. 2006AA12Z323);the National 973 Program of China (No. 2006CB701301);the National Natural Science Foundation of China (No. 40774008);the Open Research Fund Program of the Key Laboratory of Geospace Environment and Geodesy,Ministry of Education, China (06-10);the Grand Program of Zhejiang Province S and T Department (No.2008C11106-2)
Considering the differences in area, precision, datum and resolution existing among the national, provincial and urban quasi-geoids, some methods such as datum transformation and weighting according to precision are p...