Half coal rock lane quick-excavating technique under the condition of "two hard" has always been a main excavating problem influencing the Datong mining Cop.

前言：“两硬”条件下半煤岩巷掘进一直是影响大同煤矿集团有限责任公司采掘关系的主要问题。

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Conservators at the Wiltshire and Swindon History Centre were called in by archaeologists excavating at King Harry Lane in St Albans.

BBC: Secrets of St Albans' Roman burial urns unlocked