Fuzzy integrated assessing theory was used in hardrockmine goaf for the first time and multifactor assessing model for goaf hazard degree was also constituted.
首次在硬岩矿山采空区评价中引入综合模糊评价理论，建立了采空区灾害危险度多因子评价模型。
2
Xinli mining area of Sanshandao gold deposit is the first hardrockmine which belongs to the under-sea deposit in our country, and only Longkou is mining coal under sea in domestic.
三山岛金矿新立矿区是我国第一个进行海底采矿的硬岩矿山，国内仅龙口在海下采煤。
3
Developing rock roadway of coal mine is a hard task at present. Mechanized drivage of rock roadway has become a common technical problem of every coal mine.