Research On Collaborative Operation Of Equipment In Container Terminal Based On Markov Chain

Container terminal is the important node of container marine and land transportation,and its operation efficiency is of great significance to container freight transportation and social and economic development.The continuous increase of container freight volume is placing higher and higher requirements on the number of operation equipment and management level of the terminal.In the dual-cycling operation mode of the quay cranes and the mixed storage of the yards,the operation connections of the quay crane,the truck and yard crane are more complicated,which are easy to cause that the container wait for operation among the equipments.Therefore,determining the number of equipments at the terminal and improving the efficiency of collaborative operate among the equipments are the key and difficult points in the research of container terminals.This paper studies the equipments allocation problem of container terminal and the equipment coordinated scheduling problem,and deeply analyzes the operation mechanism of the container terminal system and the operation relationship among the equipments.From the berth-quay crane joint dynamic allocation and quay crane-truck-yard crane coordinated dynamic scheduling,the operation efficiency of container terminal is improved.After summarizing the inadequacies of the existing literature and analyzing the operation equipment and operation procedures of the terminal,the main research contents are as follows:(1)During the development of the container terminal,the arrival number of vessels in different periods has changed dynamically.Reasonable allocation of the equipments can effectively improve the service capacity of the terminal.The number of berths and quay cranes are coordinated to improve terminal service capacity and reduce costs.A berth-quay crane cooperative allocation model with the lowest cost is constructed,and the nonlinear transition probability Markov chain is designed to calculate the queuing length parameters of the allocation model.The calculation results of the queuing length calculated by the Markov chain method and queuing theory formula are compared with the actual situation of the terminals.which proves that the Markov chain improves the solution accuracy by 6.38 %,and provides a basis for the accurate solution of the allocation model.Finally,the results of the allocation model are solved by the simulated iterative algorithm and Markov chain,which prove the effectiveness of the model and method,and can effectively reduce the terminal operation cost.(2)Dual-cycling operation of quay cranes and mixed storage of yards can effiectively improve the operation efficiency of the container terminal,but complicate the operation connections of the quay crane,the truck and yard crane,which are easy to cause that the container wait for operation among the equipments,and increase the instability of the container terminal.The characteristics of dual-cycling operation,the constraint of operation in terminal and mixed storage of yard are considered.By integrating the problems of quay crane allocation problem,quay crane scheduling problem,yard truck scheduling problem and yard crane scheduling problem,a mathematical model of quay cranes,yard trucks and yard cranes cooperative operation with the minimum penalty time for vessels departure is established,and a hybrid algorithm with double feedback loops and multiple greedy rules is designed.(3)The quay cranes,yard trucks and yard cranes cooperative operation model is analyzed,and a simple lower bound of the model is designed.The results solved by the algorithm are compared with the simple lower bound of the model,and the effectiveness of the algorithm designed in this paper is proved.Then,by comparing the operation time,the penalty time and the GAP solved by other algorithms,it is proved that the hybrid algorithm has good performance,and the feedback loop mechanism in the algorithm is effective for reducing the average penalty time of the vessels.