Co-scheduling of lock and water-land transshipment for ships passing the dam

Display Omitted A co-scheduling model of lock and water-land transshipment mixed transport system is built.Genetic operators based artificial bee colony is proposed to solve the co-scheduling model.Width sorting fast dispatch and first-come-first-served strategy are used to solve lock schedule.The proposed model is tested by co-scheduling system of Three Gorges dam.Comparative studies show that the proposed method is effective for solving co-scheduling model. In this paper, we take the water-land transshipment as new efficient way to share the pressure of the lock for ships passing a dam. A co-scheduling model of a single lock and different kinds of water-land transshipment docks mixed transportation system for ships passing a dam is established. The model is divided into two layers, in which the outer layer refers to the decision of the ships between the lock mode and the water-land transshipment mode. The inner layer concerns the lock scheduling for ships which choose to pass the dam through lock and the berth scheduling for the others that select the water-land transshipment mode. A genetic operators based artificial bee colony (GB-ABC) algorithm is utilized to optimize the combinatorial problem in the outer layer. The berth scheduling sub-problem in the inner layer is identified as the identical parallel machine scheduling problem which is solved by first-come-first-served (FCFS) strategy. The lock scheduling sub-problem is solved by a method which takes into account both fairness of the ships and efficiency of the lock. The experiments show that an appropriate coordination between the lock and the water-land transshipment docks can help to decrease the waiting time of the ships and relief the congestion of the water traffic around the dam especially when the throughput capacity of the lock is insufficient.