Research on intelligence recognition and reconstruction of engineering graph

In the paper, the authors put forward a regulation-based expert system which is used in auto-recognition and reconstruction of engineering graph. It consists of four parts-dynamic fact library, static regulation hʹbrary,inference control and 3D reconstruction. it discribles the knowledge and regulations to reeongnize engineering graph with regulation- expressing method, and sets up the inference mechanism according to its recognition thoughts. At last, it introduces recognition results of 3D reconstruction with AutoCAD.