Using the ultrasonic wave detector to probe the flexible range of the extraction tunnel, grasping the rule of deformed tunnel directs the supporting design of the tunnel bolt.
利用超声波探测仪探测回采巷道的松动范围，掌握巷道的变形破坏规律，以此指导巷道的锚杆支护设计。
2
A mathematical model of a metal detector is established based on the principles of eddy current detection, which provide a theoretical criterion for selection of parameters of roof boltdetector.