track distribution design
engineering district；maintenance of way section；track division；track district；track maintenance division
product distribution distortion
Poisson-Poisson distribution Poisson-Binomial distribution Compound distribution
Poisson—Poisson分布Poisson－二项分布复合分布
jointless line；continuously welded rail track；jointless track
non-NTDS track {dummy track}
replacing and laying track with track panel
track-to-track association
track-to-track moving time
transforming single track into double track
double - track existing single track line
air distillation and reduced pressure distillation
Ground distortion characteristic and permission distortion value
logistical distribution physical distribution
Rosin-Rammler distribution and amendatory Gauss distribution