Analytical Analysis and Field Observation of Break Line in the Main Roof over the Goaf Edge of Longwall Coal Mines

<div>Schematic of the YSZ(B) panoramic borehole camera system. (a) Digital panoramic borehole camera system composed of a camera, sleeve, a camera position recorder, dateline, and a host. (b) Test equipment.</div>

Mathematical Problems in Engineering

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Figure 13

Figure 13: Analytical Analysis and Field Observation of Break Line in the Main Roof over the Goaf Edge of Longwall Coal Mines 