jgg     2014 34 (2):  124-127    ISSN: 0412-1961  CN: 21-1139/TG ADJUSTMENT OF GRAVITY NETWORKS BASED ON  WEIGHTED CONSTRAINTS 1）Xi’an Division of Surveying and Mapping，Xi’an〓710054 2）State Key Laboratory of Geodesy and Earth’s Dynamics，Wuhan〓430077 Received: 2013-10-17  Revised: null  Online: 2014-04-21 Supporting info