Study On Production Scheduling Of A Printing Workshop Considering Logistics Constraints

Production scheduling is the core of workshop management.Due to the complexity of the problem,various scheduling objects often have conflicts and constraints.At the same time,there are many uncertain disturbance factors in the workshop.The research object of this paper is the production workshop of M printing plant.Aiming at the problems of low on-time delivery rate and high inventory cost,considering the logistics factors,the production scheduling of the workshop is studied.The specific research is as follows :Taking the production workshop of M printing plant as the research object,this paper summarizes and analyzes the original scheduling scheme,production equipment and product process,deeply studies the problems existing in the enterprise,understands the importance of workshop logistics factors,and establishes the research direction.Considering the unique logistics constraints of M company,a bi-objective scheduling model considering logistics constraints is established with the goal of minimizing the total processing time and the sum of inventory cost and delayed delivery penalty cost.Aiming at the solution of the dual-objective scheduling model,the crowding calculation,crossover and mutation operations of the NSGA-II algorithm are improved.After the validity of the algorithm is verified by a classical example,the actual production scheduling problem of the workshop is solved,and the optimal scheduling scheme is selected from the Pareto optimal solution set by the improved TOPSIS scheme evaluation method.Aiming at the three disturbance events in the production workshop,the dynamic scheduling scheme combining periodicity and event-driven is proposed by using the right-shift rescheduling,local rescheduling and full rescheduling schemes respectively,combined with the rolling window technology.Under the condition of ensuring the continuous and stable production of the workshop,the production scheduling cost is reduced and the influence of disturbance events on the actual production is reduced.Plant Simulation software is used to compare the original scheduling scheme with the scheduling scheme in this paper to verify the effectiveness of the scheduling scheme in this paper.The results show that the scheduling model considering logistics constraints is more in line with the actual production process than the traditional scheduling model.Improved NSGA-II algorithm to solve the model has better convergence and optimization;the dynamic scheduling scheme for different disturbance events can effectively deal with disturbance events,ensure the continuous and stable production of the workshop,so as to improve the on-time delivery rate of orders,reduce inventory costs and improve customer satisfaction.