Particularly some unknown around the state-owned mine goaf is one of the most important damage source to impact on the mine safety.

特别是一些国有矿山周边的不明采空区，是影响矿山安全生产最主要的危害源之一。

youdao

Particularly some unknown around the state-owned mine goaf is one of the most important damage source to impact on the mine safety.

特别是一些国有矿山周边的不明采空区，是影响矿山安全生产最主要的危害源之一。

youdao