Integrated Scheduling Methods Based On Synchronized Loading And Unloading Operations In Container Terminal

Loading and unloading containers by quay cranes (QCs) and vehicles are studied in this paper.Based on synchronized loading and unloading technology, which is deeply researched in practicalapplication on terminal scheduling, integrated scheduling methods in container terminal isproposed. Mathematical models are established to minimize the total working cost of QCs andvehicles. Intelligent optimization algorithms are adopted to solve this problem. By numericalsimulation, engineering application, containers’ optimal loading and unloading sequences areprovided. Compared with the traditional single cycling operations, integrated scheduling methodsbased on synchronized loading and unloading operations are confirmed of great significance toreduce operation cost, and improve operational efficiency. The main research contents of this paperare introduced as follow:Firstly, loading and unloading process in container terminal is introduced, as well as thehanding facilities, container ship layout, loading and unloading scheduling. Synchronized loadingand unloading method is brought in. The definitions of hatch, bay, stack in container ship layoutare given for the use of follow-up synchronized loading and unloading methods.Secondly, scheduling method based on simultaneous hatches operations is proposed by theminimum synchronized unit of hatch. Afterwards, on the basis of the simultaneous hatchesoperations, scheduling method based on simultaneous bays operations is recommended on onehand to save the vehicles working cost. On the other hand, each hatch being subdivided into stacks,a scheduling method based on simultaneous bay operations is presented. Then, mathematicalmodeling, algorithm-calculating, examples analyses are brought in for above three methods toproving the feasibility and effectiveness of each method.Thirdly, by synthesizing each method, the integrated scheduling method based onsynchronized loading and unloading operations is designed. Stack is the minimum synchronizedunit in this method. Then simultaneous bays operations for realizing multi-bay synchronization isadopted on the basis of optimization of same-bay synchronization to obtain the optimal calculationof loading and unloading sequences and least cost about QCs and vehicles in the total containers inone ship. Finally, synchronized loading and unloading method is applied to Ningbo Gangji TerminalCompany Limited of Ningbo Beilun harbor. By the real date calculation, the advantage ofintegrated scheduling methods based on synchronized loading and unloading operations incontainer terminal is proved concerning handing efficiency.