Research On Remanufacturing Flexible Job Shop Scheduling For Damaged Parts

At present,the problems of global energy depletion and the continuous deterioration of the natural environment have become increasingly prominent.The implementation of the remanufacturing industry has become an effective way and an inevitable choice for realizing resource recycling and circular economy.The rational planning and management of the remanufacturing job shop can effectively improve the energy efficiency,alleviate energy pressure and promote sustainable development.The production scheduling problem of remanufacturing job shops that are related to balancing economic interests and environmental resources has been widely concerned by scholars at domestic and overseas.Because the processing path of the remanufacturing job shop is more complicated,it is a typical remanufacturing flexible job shop.Therefore,this paper studies the production scheduling problem of remanufacturing flexible job shop,and provides theoretical support for the production decision and management of the remanufacturing industry.The main contents of this paper are as follows:Due to the existence of batch processing equipment in the remanufacturing flexible job shop,and the difference in electricity price between different time periods is large,even if the same type of workpiece,if the type of damage is different,the process route of repair is different as well.For this remanufacturing flexible job shop scheduling problem,with the optimization of the maximum completion time and the cost of electricity in the production process,a new mixed integer linear programming model,based on the batch processing in remanufacturing flexible job shop,has been established.In order to solve the mathematical model,based on the traditional genetic algorithm,designed the crossover and mutation operator of the genetic algorithm in accordance with the model.Finally,the simulation example is used to prove the superiority of the mathematical model.Next,in the remanufacturing flexible job shop,even the same type of damage of the same kind of workpiece,the processing time of each process is also uncertain.In order to represent the uncertain variables in the workshop,triangular fuzzy variables representing the processing time and trapezoidal fuzzy variables describing the completion time of the jobs are introduced,and a fuzzy mathematical model is established to minimize the maximum completion time and machine standby time.Based on credibility theory,fuzzy simulation,the mathematical model is solved by Tabu search algorithm.In the case application,the optimal scheduling scheme is analyzed for different confidence levels,which proves the validity and feasibility of the model.Finally,the incidents in the remanufacturing flexible job shop may lead to the production arrangement not being able to follow the expected scheduling schedule,or the need to reschedule the scheduling problem to facilitate operation of the remanufacturing flexible job shop.The dynamic scheduling model of the flexible job shop is designed.The model is based on the emergency of the delivery time of the jobs.The priority problem between the orders is designed.Considering the change of the delivery date of the workpiece,the priority change and the sudden failure of the machine are designed.A new coding method is used to solve the model by genetic algorithm,and the validity of the model is proved by combining the cases.This paper considers a variety of situations in remanufacturing flexible job shop,and proposes various scheduling models to provide technical support for the planning and management of remanufactured flexible job shop.