Extended Petri Net And Genetic Algorithm-based Segmentation Workshop Virtual Pipeline Scheduling

Shipbuilding is a strategic industry, related to national security and national economic development,the best expression of a national technical capacity and economic strength .The shipbuilding is a typical large-scale equipment manufacturing industry,with labor,capital and technology-intensive features.At present,with the intensifying of the mode of traditional to modern shipbuilding mode,shipbuilding industry's overall technological level between china and the traditional shipbuilding countries such as Janpan and South Korea is still a big gap.In order to transform from the large shipbuilding country to the powerful shipbuildiong country,improving efficiency is a nessary way for Chinay's shipbuilding enterprise.Since ship block scheduling's feasibility and timeliness is poor,the main constraints to improve efficiency,so study of ship block scheduling problem has significance.According to the hull cruved ship block's characteristics,this paper reference the virtual flow line,which combined Fixed-position mode of production and assembly line, at a fixed station used in assembly line production process organization operation in order to improve the productivity of the hull cruved ship block.Firstly, describes the virtual assembly line's background, basic principles and operation of virtual assembly line of the key technologies: the job of building a team, production cycle to determine, over the same period of duration. Secondly ,based on study of the basic theory of traditional Petri nets and its'short this paper proposed a extend Petri nets, which based on timed Petri net and colored Petri net and established the basic model to model the workshop.Thirdly, build operations team, set up the mathematical models of the virtual flow line based on operations team. Finally, studies of modern shipbuilding model based on the virtual flow line production system and model the system development process base on UML.The virtual flow line in ship block building ,integrating fixed-station and flow line,can effectively improve the efficiency of shipbuilding,reduce production costs ,and enhance the core competitiveness of shipbuilding industry. So study of ship block scheduling based on virtual flow has significance.