Optimal Inspection Scheduling Model for Monitoring Railway Track Grids
Table 4
Comparison of actual and optimized track inspection schedule.
Item
Inspection schedule using the OISM-RTG
Actual inspection schedule prepared by the field engineers
Constraint system
Time constraints between activities
Satisfaction
Satisfaction
Fixed duration constraint
Satisfaction
Violation. For example, the rail detection trolley inspection is not scheduled for track segments between 757.2 and 762 km in the downward direction of the Lanxin railway.
Space constraints between activities
Satisfaction
Violation. For example, the track geometry trolley inspection and manual inspection are simultaneously scheduled for track segments between 747.2 and 758.8 km in the downward direction of the Lanxin railway.
Rate constraint of activities
Satisfaction
Violation. For example, on December 26th, the track geometry trolley inspection is scheduled for track segments between 741 and 760 km in the downward direction of the Lanxin railway. The inspection rate is 19 km per maintenance window and is nearly double the upper inspection rate limit (10.6 km per maintenance window).
Resource constraint
Satisfaction
Satisfaction
Continuity constraint
Satisfaction
Satisfaction
Objectives
Equilibrium THR
0.980
0.800
Robust r
0.161
0
Weighted objective function
0.570
0.400
Visual presentation results
A comparison of Figures 7 and 8 shows that the inspection schedule using the TGOISM-MRT model is superior to the actual inspection schedule prepared by the field engineers.