抄録
The purpose of the present study was to develop a mathematical model for effective operation of a longwall working face in an underground coal mine. The model can evaluate the relationship between operating efficiency and working height of the face in a coal seam. The results show that, contrary to a common thought, the working height of the face must be 20-30 % lower than the thickness of the coal seam. As a consequence, low-grade coal near the bed and roof rock remains in the coal seam. The results of this model enable effective operation of the working face and maximum profit in a mine.
