考虑潮汐的多港池港口船舶调度优化

Ship scheduling optimization in multi-harbor basin port considering tidal influence

针对多港池港口船舶调度优化问题,重点考虑大型船舶乘潮进出港口的影响,兼顾单向航道下进出港船舶间需保持安全航行距离、进出港时段交替条件及连续泊位靠泊限制等现实约束,以所有船舶总等待时间最小为目标,构建了混合整数线性规划模型.基于船舶调度问题的特点,提出了启发式规则,将原问题分解为五个子问题进而获得初始解,并设计了改进和声搜索算法求解.在数值实验中,将该算法的求解结果同下界对比,平均相对偏差为2.19%,且求解耗时均少于1分钟,验证了算法的有效性;将方案的求解结果同两种现行调度规则对比,不同算例规模下平均目标值优化率分别为13.30%和27.35%,可显著提高港口船舶服务效率,验证了方案的有效性.

To optimize the ship scheduling in multi-harbor basin port, this paper focuses on the influence of large ships in/outbound harbor with tidal condition. A safe navigation distance for ships in/outbound harbor in one-way channel, in/outbound harbor time alternating conditions and berth limit of continuous berth is considered. A mixed integer linear programming model is proposed to minimize the total waiting time of all ships. Based on the characteristics of ship scheduling optimization, the original problem is decomposed into five sub-problems to obtain initial solution, and the improved harmony search algorithm is designed to solve the problem. In the numerical experiments, the proposed algorithm is compared with the lower bound of the model to illustrate the validity of the algorithm. Results show that the average relative deviation is 2.19%, and the computation time is less than 1 minute. The analyzing results are compared with those under two existing scheduling rules, in which the optimization rates of average objective values are 13.30% and 27.35% respectively for different experiment sizes. The proposed model and algorithm can significantly improve the service efficiency of the port for ships and verify the effectiveness of the schedules.