Fuzzy integrated assessing theory was used in hard rock mine 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。

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Xinli mining area of Sanshandao gold deposit is the first hard rock mine 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。

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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.

目前煤矿岩巷开拓任务重，岩巷机械化掘进成为各矿普遍存在的技术难题。

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