Study of Shipment Routing Problem under Uncertainty and Its Tree-shaped Path Constraint Mechanism
In response to the limitations of deterministic modeling parameters in existing shipment routing studies and the controversy over whether tree-shaped path constraints should be considered in the shipment path optimization stage,the fuzzy set theory and stochastic programming theory were introduced in this paper on the basis of a deterministic shipment routing model.The fluctuation of car flows and the elastic passing capacity of intervals were described by using triangular fuzzy numbers and chance constraints,respectively,to reconstruct a fuzzy chance constrained programming model under Hurwicz criterion for the shipment routing problem,which was then transformed into a clear equivalent form.Based on a case study of a local rail network in southwest China,the impact of the tree-shaped path constraint mechanism on ship-ment routing and train formation plan was investigated,while the differences of shipment paths under deterministic and uncertain conditions were compared and analyzed.The experimental results show that emphasis on tree-shaped paths in the shipment path optimization stage will limit the flexibility of the path plan and increase the total car flow transportation cost.The shipment routing model under uncertainty is more advantageous in the identification of difficult sections.
NETL
NSTL
万方数据
