Roof control is key management of opening up coal seam with potential outburst in crosscut.

顶板管理是石门揭露突出煤层过程中的管理重点。

youdao

Roof control is key management of opening up coal seam with potential outburst in crosscut.

顶板管理是石门揭露突出煤层过程中的管理重点。

youdao