Modeling And Optimization Of Typical Dispatching Problems In Ship Assembly And Construction Phase

The 21 st century has entered the information age,and the shipbuilding industry has undergone earth-shaking changes.Although China has become the world’s largest shipbuilding country,it is not yet a strong shipbuilding country.Many shipyards’ production plans are out of touch with actual operations,resulting in a large waste of resources..The ship is a complex discrete system,and many factors affect the construction plan in time and space.In this paper,combining the characteristics of shipyard operations,using the Plant Simulation platform to simulate the actual operating conditions of the shipyard,using genetic algorithms to optimize,and then get the best ship construction plan,eliminate the discontinuity of the plan and the imbalance of resources,improve shipbuilding efficiency,and reduce Shipbuilding costs.The main content and research results of the paper are as follows:(1)Introduced the current situation of the shipbuilding industry and explained the problems in domestic shipbuilding production,summarized the domestic and foreign research status of the block yard scheduling process,gantry crane resource balance,discrete system simulation technology,etc.,and explored the predecessors The lack of work finds out the innovative points of this paper.Analyze the discrete event system simulation software,Plant Simulation functions and characteristics,and the realization of genetic algorithm,determine the feasibility of Plant Simulation discrete simulation software and genetic algorithm in the application of ship construction simulation in this paper,and pave the way for subsequent research.(2)Aiming at the optimization problem of block yard scheduling,a large shipyard in Dalian was used as a research background,and a model was built based on the Plant Simulation platform.The comprehensive movement difficulty change diagram of the flatbed trucks in the factory’s monthly scheduling plan was displayed in one year.The time and space constraints in segment yard scheduling are optimized with the lowest difficulty of comprehensive movement in segments.The genetic algorithm is used to optimize.The experiments on yards with different initial load ratios are analyzed and compared.The results show that the optimization The later approach segmented parking strategy effectively reduces the segmental comprehensive movement difficulty,and it is found that the segmented comprehensive movement difficulty is directly proportional to the initial load rate of the yard.(3)Aiming at the problem of gantry crane resource balance under multiple constraints during the staged loading process of the dock,a model is built based on the Plant Simulation platform,and the optimization goal is to minimize the difference in the number of tasks carried by the two gantry cranes.The genetic algorithm is used for optimization and optimization.The actual staged loading plan of a large shipyard in Dalian is used as simulation data to verify the simulation data.The results show that the optimization results can effectively balance the workload of the two cranes.