This paper presents a study on the criterion of crack initiation and propagation under creep conditions, which were investigated using specimens collected from
<正> Based on the number of fatalities per year,a persistent area of concern in minesafety continues to be equipment related.Data from the period 1995 through 2
The effect of geological uncertainty on the development and mining of undergroud coal deosits is a key issue for longwall mining,as the presence of faults gener