The Stochastic Service System Model and Optimization Research about Order Batch-ing Problem for Logistics Distribution Center
|School||Beijing Materials Institute|
|Course||Management Science and Engineering|
|Keywords||Manual order picking system Order batching stochastic servicesystem Genetic algorithm Greedy algorithm|
With the rapid development of e-commerce market and economic integration, atthe distribution center, where multi-variety and small batch order is given priority to,or more demands of personal products, manual order picking system is still the mainway Research on the optimization and control about manual order picking process, isof great significance to distribution center about warehouse management, which caneffectively increase customers’ satisfaction, reduce the distribution center’s deliverycost and improve the service level of the whole supply chain.Among the related studies of the optimization and control about manual orderpicking process, is mainly focus on storage strategy, picking strategy and routingstrategy. Research shows that batching policy is the primary influences on costreduction, which can effectively reduce the picking distance and resourcesconsumption. Therefore, this paper makes a study of the random service systemmodel and optimization research about order batching problem.This paper considers the randomness of the orders’ arrival and the items of thecategories and quantities. For online order accept system, the randomness of theorders’ arrival determines the arrival queue of the order is a random process; therandomness of the items each order contained of the categories and quantities, makethe picking time is random, namely service is random. Therefore, this paper willconsider order batching as the stochastic service system which input process is theorder random arrival and the services are the manual batch picking.This paper applied stochastic process theory, under ABC class-based storage andS-type picking condition, research the random order’s turnover time (includingwaiting time for batch formation, waiting time for service and service time) influenceon the order batch stochastic service system. The stochastic models about batch sizewere built for logistics distribution center; the optimal batch size order is the batchsize when the average turnover time is the smallest. At the same time, through thesimulation by matlab, the simulation results and the model approximation solutionresults are compared and analyzed, the conclusion is that the optimal batch size andits lower bound is similar, so we can use genetic algorithm to solve order batchingstochastic service system model to find the batch size of the lower bound, then, usethe greedy algorithm to find the optimal batch size, which realize the optimization research of the order batching stochastic service system.Research on the random service system model and optimization research aboutorder batching problem enrich the optimization theory and methods and lay thefoundation for deepening and perfecting manual order picking process in some ways.