Modeling And Heuristics Of Cross Docking Scheduling With Stochastic Demand

This thesis studies the modeling and heuristics of cross docking scheduling problem with stochastic demand. Cross docking is an operation that moves goods directly from receiving point to shipping point without storage. There are two stages in cross docking scheduling: the first stage in which goods are collected from suppliers to cross docking center by vehicles, the second stage in which goods are sent from cross docking center to customers. Cross docking scheduling can be classed into two classes by the transportation model: direct delivery and milk run. Cross docking scheduling problem is a kind of vehicle routing problem.The randomness of demand always occurs in practical scheduling and is difficult to avoid. Also it's widely studied in stochastic scheduling. However, it's seldom studied in cross docking scheduling. This thesis analyzes cross docking, transportation models and vehicle routing problems. The stochastic demands in cross docking systems with different transportation models are analyzed. Reasonable assumptions and data generating methods are introduced.According to different transportation model, this thesis studied two kinds of cross docking scheduling problems with stochastic demand:(1) The modeling and heuristics of two-stage direct directly cross docking scheduling with stochastic demand. First, the problem is described and assumptions are raised. A two-stage recourse model, a SAA based heuristic and a two-stage heuristic are presented. According to the numerical experiment about solution effectiveness and steady in small scale, the SAA heuristic and two-stage heuristic are proved to be effective.(2) Modeling and heuristics of direct directly - milk run mixed cross docking with stochastic demand. First, the problem is described and assumptions are raised. A two-stage recourse model, a SAA based heuristic and a capacity reservation based two-stage heuristic are presented. According to the numerical experiment about solution effectiveness and steady in small scale, the SAA heuristic and two-stage heuristic are proved to be effective. And the best parameter settings are given by the large scale numerical experiment.This thesis aims to provide decision support for the practical cross docking operation in logistics companies. Also, the research aims to be applied in the practical operation and provide the theory support and useful heuristic for the scheduling management in cross docking system.