Research On Optimization Of Block Transportation Scheduling Between Storage Yards

With the rapid development of information technology,shipbuilding mode has been continuously improved in the direction of intelligentization and refinement.As a kind of traditional commodities,ships were divided into several blocks during the production.These blocks would be assembled in the dock after a series of processing technology in different workspaces further.Due to the limitation of workspaces,the processed blocks need to be transported to the yards for storages and inspections.The transportation between workspaces and yards depends on heavy flatcars.If one task is delayed,other subsequent production processes would be affected.Meanwhile,different transportation plans contributed to different costs,so reasonable transportation is essential.Therefore,in view of the lack of effective scheduling of the flatcars during the shipyard production process,this dissertation studied the transportation scheduling of flatcars during the block construction of ships in following aspects.First of all,for one-flatcar and one-block transportation,consider various load-bearing capacity of flatcars and weight of blocks,time windows as the constraints of the model,and the unloading travelling time of all flatcars is the optimization target of the model.When the shipyard actually works,the task scale is large.Some exact algorithm is difficult to solve in the limited time,so we design genetic-tabu search hybrid algorithm.First,use genetic algorithm to solve a highly qualified feasible solution,and then use tabu search algorithm to solve the optimal sequence,at last,the optimal path considering the number of turns is solved by the deep first search algorithm,so as to realize the solution of the model.Secondly,for the maximum load-bearing capacity of an existing flatcar is less than the weight of a large block,the cooperative transportation using multiple flatcars is used.The load-bearing constraint of multi-type flatcars and task blocks,the task time windows constraint are the constraints of the model,and weighted sum of unloading traveling time and the waiting time due to early reach or multi-flatcars cooperative transportation are the optimization target of the model.Time update mechanism is designed.The tabu search algorithm is designed to solve the model.Finally,a set of ship block yard scheduling system is developed.Taking the actual production data of a shipyard in Shanghai as an example,the application of the model and algorithm is verified,and the results show that the method proposed in this dissertation can solve the better scheduling scheme and realize the efficient utilization of resources.