Research On Contact Net Protocol Based Scheduling Approaches For Steelmaking-Continuous Casting Production Process

The steelmaking-continuous casting process is the bottleneck of steel production. Effective production schedules can improve equipment utilization rate, reduce process waiting time, and increase productivity. However, currently most steelmaking-continuous casting production scheduling problems belong to NP-Hard problems, and making effective production scheduling is a crucial factor for steel industry.Based on the multi-agents theory of contract nets, an intelligent scheduling strategy for steelmaking-continuous casting is proposed in this paper. The main research work is as follows:(1) An improved contract nets method is proposed. Mulit-agents alternately Interacting with each other adopting contract net protocol is one of the most focused research on scheduling issues. However, the classic contract net models have problems of large amount of communication and low efficiency. To overcome the above deficiencies, an improved contract nets method is proposed by introducing mental parameters like acquaintance set, trust degree.(2) A steelmaking-continuous casting scheduling model based on agents is constructed. Task allocation and equipment negotiations are realized by employing improved contract net protocol method and a workshop scheduling algorithm based on multi-agents is designed as well.(3) The scheduling algorithm proposed in this paper is verified using steelmaking-continuous casting simulation system which is based on multi-agents. Through comparing the efficiency and optimization results with the original scheduling method of the simulation system, it is concluded that the new method put forward in this paper effectively reduces the communication amount, improves the simulation efficiency, and shorten the simulation time.