Locomotive Scheduling Using Constraint Satisfaction Problems Programming Technique

  • Hwang, Jong-Gyu (Dept. of Railway Electrical and Signaling Research, Korea Railroad Research Institute) ;
  • Lee, Jong-Woo (Dept. of Railway Electrical and Signaling Research, Korea Railroad Research Institute) ;
  • Park, Yong-Jin (Div. of Electronic Engineering, Hanyang University)
  • Published : 2004.03.01


Locomotive scheduling in railway systems experiences many difficulties because of the complex interrelations among resources, knowledge and various constraints. Artificial intelligence technology has been applied to solve these scheduling problems. These technologies have proved to be efficient in representing knowledge and rules for complex scheduling problems. In this paper, we have applied the CSP (Constraints Satisfaction Problems) programming technique, one of the AI techniques, to solve the problems associated with locomotive scheduling. This method is more effective at solving complex scheduling problems than available mathematical programming techniques. The advanced locomotive scheduling system using the CSP programming technique is realized based on the actual timetable of the Saemaul type train on the Kyong-bu line. In this paper, an overview of the CSP programming technique is described, the modeling of domain and constraints is represented and the experimental results are compared with the real-world existing schedule. It is verified that the scheduling results by CSP programming are superior to existing scheduling performed by human experts. The executing time for locomotive scheduling is remarkably reduced to within several decade seconds, something requiring several days in the case of locomotive scheduling by human experts.


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