Pratice and Research to Observe Three-dimension Dynamic Deformation of Bridge Constantly by Automatic ETS
jiang ghenguang 1 liu hua 2 liu guifang 3 huang jiaxing 4 (1.laiyang agricultural college; 2.guliu territorial resources management centre of laiyang city; 3.heluo territorialresources management centre of laiyang centie of laiyang city; 4.archidectural design and prospecting iostitute of ner monggol autonomous region)