Research On PBL Two Echelon Spare Parts Inventory System With Time-varying Demand Optimization Model And Application

In recent years,the original equipment manufacturers(OEM)have gradually developed from the simple competition of product prices and quality of products to the competition of the after-sales service.Performance Based Logistics(PBL)also becoming the new mode of aftersales service of the mission-critical equipment,PBL requires that the customers pay according to the performance(system availability)provided by suppliers.For equipment suppliers,need to consider that under PBL,how to set up spare parts inventory level and the corresponding maintenance capability etc.According to the stage of the market of the expansion of the new equipment,and the nonlinear time-varying demand feature that created by different regional market installed speed and failure rate,based on the regional market fast service and overall service system cost into the consideration,two spare parts inventory structure has become the main mode of most equipment supplier after-sales service system.Aiming at the new problems of the two echelon spare parts inventory system under PBL,this paper mainly studies the following 3 aspects:(1)Research on the non-repairable spare parts inventory control model of the two echelon spare parts under time-varying demand.To the non-repairable spare parts and two spare parts inventory system structure,under multi-level availability revenue function of PBL model and increasing variable maintenance requirements of new equipment market expansion phase,using system availability(spare part fill rates)as a performance criteria of suppliers service,and using the multi-stage(Q,R)inventory policy,decide central warehouse and local warehouse inventory optimal number of inventory policy stages,and the optimal inventory level of each stage,thereby allow suppliers to obtain the maximum profit.(2)Research on the repairable spare parts inventory control model of the two echelon spare parts under time-varying demand.To the non-repairable spare parts and two spare parts inventory system structure,under multi-level availability revenue function of PBL model and increasing variable maintenance requirements of new equipment market expansion phase,due to limited repair capacity of system and limited equipment number at equipment rising stage,adopting M/M/c/?/nk queuing model,using system availability(spare part fill rates)as a performance criteria of suppliers service,and using the multi-stage(S-1,S)base inventory policy,decide central warehouse and local warehouse inventory optimal number of inventory policy stages,and the optimal inventory level of each stage,thereby allow suppliers to obtain the maximum profit.(3)Research on enterprise application case.Using spare parts service of market expansion phase of new CT of D medical group as an example,according to the relevant data,A genetic algorithm is used to solve the models,by means of sensitivity analysis of the supplier profit is affected by the growth rate and failure rate of CT,analysis of supplier's profit is affected by M/M/c/?/nk and M/M/c/?/?,and value analysis of PBL performance index,verify the validity and superiority of the model.In theory,this paper has combined the PBL model with the traditional model of spare parts inventory control problem,according with the reality of equipment manufacturers to service competition change,at the same time,using the finite source queuing model M/M/c/?/nk quantifing the limited repair ability of the equipment suppliers,to more accurately describe the research background of new equipment expansion stage.In the aspect of application,this paper has given some inspiration for manegers that how to set up spare parts inventory leve under the mode of PBL,how to set the supplier maintenance capacity and cognitive that the failure rate of the equipment effects supplier profit.