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Research On Flexible Job Shop Scheduling Problem Based On Immune Multi-agent System

Posted on:2019-06-10Degree:DoctorType:Dissertation
Country:ChinaCandidate:W XiongFull Text:PDF
GTID:1312330548457887Subject:Control Science and Engineering
Abstract/Summary:PDF Full Text Request
With the change of mode of production,the flexible job shop scheduling problem(FJSP),which is widely applicable and hard to solve,is more realistic in manufacturing field.The centralized scheduling approaches,represented by the meta-heuristic algorithms,are wasteful of computational time and bad in response to dynamic events.Multi-agent system not only effectively reduces the complexity and computational time,but also increases the flexibility and robustness of scheduling system.However,the quality of solution obtained by the multi-agent system is always worse than the centralized meta-heuristic algorithms.The immune system is a distributed and complicated information processing system,which can quickly protect body from foreign antigens by immune responses.If the operations are compared to the antigens,the scheduling system can schedule the operations according to the mechanisms of immune responses,iin order to quickly acquire the high quality solution.This paper simulates two important immune theories to develop the immune mult i-agent scheduling systems for solving the various FJSPs.The main works and innovative points are as follows:(1)The meta-heuristic algorithms spend more time solving the FJSP.The multi-agent approaches and heuristic algorithms are hard to acquire the optimal solution.For surmounting the above disadvantages,a multi-agent approach based on the clonal selection theory is proposed to develop a new immune multi-agent scheduling system,which solves the FJSP with the objective of minimizing the maximal completion time.The heuristic scheduling rule based on the B cell activation value is designed by simulating the clonal selection theory.The greedy mechanism is designed to find out the Nash equilibrium solution.The mechanisms of B cell hypermutation and affinity maturation,combined with the critical path method and tabu search,are used to deeply optimize the scheduling result.The results of simulation experiments and algorithms comparison indicate that the new immune multi-agent scheduling system can quickly acquire the high quality scheduling result.(2)The priori approaches are hard to acquire the satisfactory solution,and the posteriori approaches spend more time solving the multi-objective FJSP.For surmounting the above disadvantages,a multi-agent approach based on the B cell league is proposed to develop an immune multi-agent multi-objective scheduling system,which solves the multi-objective FJSP with the objectives of minimizing the maximal completion time,maximal machine workload and total workload ofmachines.The system progressively obtains the preference of the decision-maker,and acquires the satisfactory solution through mutual optimization and compromising optimization.The different schedules are searched by creating the different B cell leagues.The results of simulation experiments and algorithms comparison indicate that the immune multi-agent multi-objective scheduling system can quickly acquire the scheduling result which is in agreement with the preference of the decision-maker.(3)The steelmaking-continuous casting dynamic scheduling problem with delay of operation is researched as the dynamic FJSP.The partial adjustment approaches of scheduling plan based on the immune theories are proposed to respectively develop an immune multi-agent dynamic scheduling system(IMADSS)and an immune network multi-agent dynamic scheduling system(INMADSS).In IMADSS,a machine allocation approach of the affected operations,which bases on the B cell activation value,is designed by simulating the clonal selection theory.In INMADSS,an adjustment approach of the completion time of the affected operations and a machine allocation approach of the affected operations are designed by simulating the immune network theory.The results of simulation experiments indicate that the two multi-agent dynamic scheduling systems can both quickly make the dynamic scheduling plans which have the small deviation from the initial scheduling plan.They can effectively ensure the continuity and stability of the production process.
Keywords/Search Tags:Flexible job shop scheduling, Steelmaking-continuous casting dynamic scheduling, Multi-agent system, Clonal selection theory, Immune network theory
PDF Full Text Request
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