【摘要】 通过对几个放顶煤工作面的煤炭损失量的分析 ,提出提高放顶煤工作面资源回收率的措施更多还原

【Abstract】 The measures on how to raise the mining rate of resourses in sub-level coal caving face are presented,by analyzing the coal losses in caving faces.更多还原