Model of Mining the Synchronism of Retrieval Processes Between Customers for Optimizing the Import Container Allocation Problem

The container relocation problem (CRP) is an important factor affecting the efficiency in a container terminal yard. The primal cause of the CRP is the containers discordant storage permutation in each stack with the arrival orders of outside trucks. This paper, from the customer perspective, expounds a methodology for mining the synchronization of retrieval processes between customers (Syn-RPC) along with a formulation to measure the level of the Syn-RPC, called the Synchronicity Index of Retrieval Processes between Customers (SynI-RPC). On the basis of SynI-RPC, an optimizing scheme is put forward, which involves three phases -- (1) grouping with SynI-RPC, (2) yard block allocation problem (BAP), and (3) slot allocation problem (SAP). In addition, a retrieval order estimation approach for the import containers is developed for applying to the SAP, called Frequency Difference in Different Episodes of Retrieval Time Window (FD/RTW). Computational experiments validate the novel strategy effectiveness and efficiency on abatement of the expected number of reshuffles.