Optimization Model For Dynamic Yard Scheduling Based On Stacking Grids In Coal Terminal

With the development of global economic integration,waterway transport has achieved a great improvement.As the transfer station of important energy source in the country,the position of coal terminals have become more and more important in the shipping market.In addition,the yard is an important part and limited resource of the terminal,whether the arrangement of the yard is reasonable or not directly effects the handling efficiency and production cost of the terminal.According to the characteristics of the yard in the coal terminal,the paper consider the problem of yard arrangement for ships in planning period from the overall view of production planning.Then mathematical model is established,and the optimization algorithm to solve the problem is also studied.The main results of this paper are as follows:At first,the paper deeply analyses the handling technology and operation flows of coal terminals,and emphatically considers the Key influencing factors for the yard scheduling.Combined with the production practice,the paper have defined the problem of the stacking planning in the coal terminal,also the optimization criterion is proposed.Aiming at maximizing yard utilization and minimizing the total waiting time of ships,the optimization model for yard scheduling of coal terminals is established,in addition,considered stacks,operating procedures and other related constraints of the production process are considered in the model.In view of many influence-factors,complex constraints and multi-objective for the scheduling problem,this paper,based on the deep analysis of the model,has designed multi-objective genetic algorithm,which uses the class coding method to encode the population.Then a corresponding decoding algorithm is constructed.In consideration of the non-feasible individual in the process of genetic manipulation,the random repair operator is designed.After several iterations,the algorithm can obtain multiple sets of non-dominated optimal solutions.After application of the water-transfer-water coal terminal in South China,this paper has verified the engineering feasibility of the model and algorithm for yard scheduling,which has a good performance in the effectiveness of the solution,the diversity of the optimization results and the timeliness of the algorithm.