clock marker track

engineering district；maintenance of way section；track division；track district；track maintenance division

free-pendulum clock (=Shortt clock)

jointless line；continuously welded rail track；jointless track

non-NTDS track {dummy track}

replacing and laying track with track panel

track to track fusion

track-to-track association

track-to-track fusion

track-to-track moving time

transforming single track into double track

double - track existing single track line

’clock’method

18 o’clock statistic of the railway station

40 GHz clock recovery

absolute clock

access of synchronous clock

active high clock

active low clock