Research Article

Optimal Inspection Scheduling Model for Monitoring Railway Track Grids

Table 1

Variable denotations.

SDStarting mileage of the inspection schedule
EDEnding mileage of the inspection schedule
DR, which represents the mileage length of the inspection activity
LELength of the track grid is generally 200ā€‰m
N represents the total number of track grids divided by railway lines
ith track grid
MTotal number of types of track inspection methods
jth inspection method
jth inspection method of track grid
ETotal unit time in a scheduling cycle
Inspection time threshold of the jth inspection method of the ith track grid in a scheduling cycle
ā€‰Owing to the influence of various temporal and spatial factors, the inspection frequency values of the same inspection method may differ for different track grids
which represents the inspection time threshold of the total number of inspection methods of track grid in a scheduling cycle
Minimum inspection interval threshold of inspection method of track grid in the scheduling cycle
Maximum inspection interval threshold of track grid inspection method in a scheduling cycle
Threshold of the maximum number of grids inspected in the inspection method per unit time
Threshold of the minimum number of grids inspected in the inspection method per unit time
Number of workgroups performing inspection activities with an inspection method
RCTotal number of workgroups performing inspection activities