Storage Allocation Optimization Based On Simulation In An Automatic Container Terminal

The throughputs of the world’s important container terminals are increasing along the frequency of international trade.In this case,automated container terminals have emerged.Automated equipment in automated container terminals not only saves labor costs,but also standardizes the way of operation.Besides,new technology helps improve the information transfer,which is good for optimizing management.Because there is a great different between the automated and the traditional terminal,it is necessary to establish a model based on the automated terminal equipment to evaluate its efficiency.The yard is a key resource of a container terminal,and the allocation problem determines the utilization of it.The allocation of inbound containers is subject to the uncertainty of the future pick-up time,and relevant research is insufficient,which is of great research value.This paper discusses the allocation problem of inbound containers at automatic container terminals.When the quay cranes unload a batch of inbound containers,containers need to be allocated into the slots of a block.According to the Automated Guided Vehicle(AGV)and Automatic Stacking Crane(ASC)work methods,the model records the waiting time of AGV.This paper uses the simulation method to evaluate the rehandle number in the retrieval process.Minimizing the sum of the two is the objective of optimization.Based on the analysis of the factors affecting the object,this paper proposes an integer programming model and develops modified Genetic Algorithm to solve the problem.The result is the designated slot of each container in a block,which is optimized by simulation-based optimization algorithm.The numerical results show that:(1)the algorithm produces better solutions than the commercial solver(CPLEX)in a shorter computational time,and(2)the allocation scheme of inbound containers is affected by different factors,such as the initial block layout,the number of arriving containers and the containers arriving information,etc.(3)Simulation-based optimization method promotes the efficiency of retrieval operation continuously,which improves the level of terminal service.This paper makes some suggestions in different scenarios which assists the automatic container terminal operators to make decision on the allocation of inbound container.And the optimization algorithm based on simulation also provides a tool for solving the relevant scheduling problems,reducing the dependence on labor experience.To some extent,the service level of the terminal can be improved and costs are reduced.