铁路行车指挥自动化: automation system for railway traffic control
定向: directional; orient; orientation; sense of orientation; predetermined orientation 短语和例子无线电定向 radio range orientation; 给 ... 定向 give an orientation to; 定向爆破 directional [directed] blasting;
定向射线: directed beamdirected raiesdirected raysguide ray
