The calculation models are set up on average speed and Max speed in back field and jet effect distance, new theoretical reference is provided for effective ventilation in heading fa.
给出了回流区平均速度、最大回流速度及射流作用距离的计算模型，为掘进工作面合理有效通风提供了新的理论依据。
A team of Danish researchers, heading northwards on a Swedish ice-breaker, has just set sail from Norway.
一队丹麦研究人员刚刚乘着一艘瑞典破冰船从挪威向北起航。
A team of Danish researchers, heading northwards on a Swedish ice-breaker, has just set sail from Norway.
一队丹麦研究人员刚刚乘着一艘瑞典破冰船从挪威向北起航。
应用推荐