track signalled in one direction的意思|示意
美 / /
英 / /
轨道指向一个方向
track signalled in one direction的网络常见释义
单向信号线路 ... track structure in tunnel 隧道内轨道结构 track signalled in one direction 单向信号线路 track signalled in both directions 双向信号线路 ...