Research On Customer Order Decoupling Point Location In A Delayed Production System Based On Markov Theory

With the popularization of mobile internet and smart phones,the information asymmetry between buyers and sellers has been completely broken.In addition,the problem of overcapacity in various industries has become more and more prominent.As a result,the leading power of transaction has returned to the hands of customers.As an active response to market demand change in the new business era,mass customization has been more and more important and has been adopted by enterprises.In this background,this research adopts a problem-solution approach with three steps that problem recognition,problem definition and problem solution.The queuing theory,continuous time Markov chain,birth and death process,quasi birth and death process,matrix geometry method are comprehensively applied.This work concentrates on the scientific problem of customer order decoupling point location decision under mass customization environment.Specifically,the studying work mainly includes the following three parts.Firstly,a customer order decoupling point location model based on delivery lead time constraint is constructed.Consider a delayed production system consisting of a generalized production phase and a customized production phase.Using queuing theory,the delayed production system is regarded as a M/M/1 system with exponential distribution of order arrival time and production time.Accordingly,the corresponding performance indicator is obtained: expected sojourn time.Then an optimization model of delay production system under the constraint of delivery lead time is studied.In this model,the customer order decoupling point location is determined to minimize the manufacturer's total cost.In addition,the influence of order arrival rate,total production time,customized product types and delivery lead time on the location of customer order decoupling point and the manufacturer's total cost is discussed.Secondly,a customer order decoupling point location model based on process improvement investment is constructed.Considering the existence of an initial customer order decoupling point in a delayed production system,the manufacturer adjusts the initial customer order decoupling point to an appropriate position through process improvement investment,which aims to balance the contradiction between delivery lead time and the inventory holding cost of semi-finished products.Based on the theory of quasi birth and death process,the delayed production system is modeled as a two-dimensional infinite state continuous time Markov chain.Using the matrix geometry method,the steady state distribution of the delayed production system is obtained.And the system performance indicators are also obtained: the expected number of customer orders,the expected customer order fulfillment delay and the expected number of semi-finished products.Then an optimization model of the delay production system based on process improvement investment is constructed.The optimal process improvement investment level and the optimal customer order decoupling point location are determined under different initial customer order decoupling points to minimize the manufacturer's total cost.In addition,the influence of product cost,order waiting cost and process improvement investment cost on the optimal investment level and the percentage of total cost savings is discussed.Finally,a customer order decoupling point location model based on customer impatient behaviors is constructed for a delayed production system.In the case of limited raw materials,the manufacturer can only accept limited orders.Once the system receives the maximum number of orders,customers cannot enter the system and choose to balk.On the other hand,due to a long waiting time,customers entering the system may leave the system and choose to renege.To deal with these two customer impatient behaviors,the manufacturer adopts two measures to reduce the order loss: delaying the initial customer order decoupling point location through process improvement investment and increasing the semi-finished product inventory.With Markov process thought,the whole order completion process is regarded as a continuous time Markov chain with two-dimensional finite state.Using the matrix geometry method,system performance indicators are obtained:the system throughput,the expected semi-finished product inventory,the expected waiting orders quantity,the expected balking rate and the expected reneging rate.Then an optimization model of the delay production system based on customer impatient behaviors is studied.In this model,the optimal process improvement investment level and the optimal basic inventory level of semi-finished products are determined to maximize the manufacturer's profit.In addition,the influence of customer's willingness to enter the production system and waiting time in the delayed production system is analyzed.In summary,the research results are beneficial to enrich and improve the relevant research theories and methods of the delayed production system.Help enterprises improve the ability of production systems to cope with the uncertainty and diversity of demand.It provides scientific decision basis for customer order decoupling point location and has important theoretical significance and application value.