Integrated Scheduling Model For Container Terminals’ Mixed Cross-operation

In order to strengthen container ports’competitiveness and adapt to the requirements of the regional economic development, except for expanding facilities and equipment configuration scale, container terminals’production operation level and production scheduling ability should be improved at the same time, so as to improve production efficiency, reduce operating costs and shorten ships’time on port.Based on system engineering theory, container terminals’import and export operation system makes a full use of wharf berthing facilities, loading and unloading equipment, transportation equipment, stacking equipment and other hardware resources. By using the dock electronic information technology resources as the powerful support software, container terminals’import and export system utilizes berthing operation, loading and unloading operation, handling operation, stacking operation and gate control operation to realize ships’import and export process. Container terminals’ import and export system can schedule and allocate berths, quay cranes, yard trailers and yard cranes reasonably based on berthing plan, stacking plan and stowing plan. In view of the interactions and mutual influence among all the elements and links in system, in order to improve the overall production operation level and terminal operation ability, the comprehensive consideration and integrated optimization for container terminals’import and export system is very necessary.Aiming at the correlative relationship among berth allocation link, loading and unloading operation link and horizontal handling link in import and export operation system for container terminals, according to their effect on terminals’production efficiency and operation cost, deficiencies existed in separate scheduling for single link and in coordination scheduling for adjacent links in import and export operation system for container terminals are studied. Using optimization theory of system engineering, an integrated scheduling method based on mixed cross-operation is proposed, and synchronous optimization technology is put forward. Taking berth allocation, quay crane deployment, yard crane dispatch, internal trucks assignment and routing as decision variables, the integrated scheduling problem is formulated as3-stage models with the objective of minimizing terminals’total operation cost. A bi-level genetic algorithm is developed to solve the model. The upper level genetic algorithm is designed to searching for the combination of equipment configuration in container terminals. The lower level genetic algorithm is applied for searching a minimum internal trucks’travelling distance based on the upper level.The results of numerical experiments on the developed model indicate that the integrated scheduling based on mixed cross-operation can reduce internal trucks’ number by66.2%and their travelling distance by17.4%compared with loading and unloading separate-operation; the integrated scheduling can decrease internal trucks’ travelling distance by14.5%and terminals’operation cost by4.6%compared with separate scheduling. It is thus clear that the integrated scheduling for container terminals’mixed cross-operation can significantly improve terminals’production efficiency, reduce the operation cost to a great extent and realize the global optimization of the import and export operation system in container terminals.