什么是移动闭塞?
参考答案:移动闭塞将前行列车的后部看成是假想的闭塞分区或轨道电路区段,由于这个假想的闭塞分区或轨道电路区段随着前行列车的运行而移动,因此,称为移动闭塞。
— You don't forget when we borrowed that reference book, do you?
— I can't remember now but ___ sometime last week? [ ]
A. might it be
B. could it be
C. could it have been
D. should it have been
依据ISO9001:2015标准8.3.4条款,以下错误的的()
A.组织对设计和开发过程运行控制的活动就是评审、验证和确认
B.评审活动是为了评价设计和开发的结果满足要求的能力
C.验证活动是为了确保设计与开发的输出满足设计与开发输入要求
D.确认活动是为了确保产品和服务能够满足特定的使用要求或性能要求