This paper presents a novel approach to investigate the relations between drilling signals and bit wear condition in real world full-scale mining operations.Thi
Behaviors of sika deer in spring were studied by scan sampling, ad libitum sampling, and all-occurrence recording methods during 1998. The results showed that b
The hard roof difficult to collapse easily causes gas accumulation,which threatens the production safety of coal mine.Therefore,roof pre-cracking is required.Al