Simulation And Optimization On RFID-enabled Hybrid Push/Pull Control Strategies For Multi-echelon Inventory Networks In Supply Chain

Multi-echelon inventory plays an important role in management of systems in supply chain inventory. In order to reduce the inventory cost and improve the service level, the control strategies on multi-echelon systems are widely concerned by the academic communities. All kinds of uncertain factors such as the random arrival of customers bring a lot of uncertain and stochastic factors to supply chain. However, the inventory levels of supply chain are affected deeply by these uncertain and stochastic factors. And the uncertainty will be gradually exaggerated by the "bullship effect" in supply chain, and they result that too high storages or too low service levels consequently.The Push/Pull hybrid control strategy in multi-stage producing inventory system is an effective inventory control manner. The Pull strategy pulls the system to run by taking out of the finished products. Only does the worker see the empty Kanban, he can start the job in Kanban system. The character make the Kanban system difficult to apply in the wide spread inventory systems.After 2000, some scholars applied the Pull control strategy to the multi-echelon inventory system of supply chain. However, the Kanban system cannot be really applied in supply chain, the Pull control strategy is the "order pull" or "contract pull" virtually, it is difficult to give full play to the function of decreasing inventory levels and raising the serve levels. The emergence of the frequency identification devices (RFID) provides an efficient method to the innovation of inventory control strategies, as the technology of RFID can count and locate the inventory products and goods transited precisely, the appearance of RFID provides a technique method that RFID-enabled electronic Kanban system is remote real time visual. Push strategy and RFID-enabled Pull strategy can be combined to design the RFID-enabled hybrid Push/Pull control strategies for multi-echelon inventory systems in supply chain distribution network based on the RFID-enabled electronic Kanban system.Supply chain and logistics system are dynamics and have many stochastic factors. Thus, the analytical methods cannot be used to solve the problem of multi-echelon inventory networks in supply chain with complex changes effectively. The simulation method is an ideal tool to study it. The simulation method can compensate for the defects of parsing methods effectively, which is dealed with the uncertainty and complexity. Thus, the simulation method plays more and more important role in the study of supply chain. However, the simulation method is not a kind of optimization method, it cannot give the optimal solution or satisfactory solution of the problem, the simulation method and the optimization technology need to be combined to form SBO (Simulation-based Optimization) method, which can achieve real system optimization.In this dissertation, Push strategy and RFID-enabled Pull strategy are combined to design the RFID-enabled hybrid Push/Pull control strategies for multi-echelon inventory system in supply chain distribution networks based on the RFID-enabled electronic Kanban system. In addition, three-echelon inventory systems of supply chain are exemplified and eight kinds of RFID-enabled hybrid Push/Pull control strategies are designed. The assessment index system of multi-echelon inventory networks of supply chain is designed and all kinds of strategies are compared, verified and optimized based on the simulation platform and the PSO (Particle Swarm Optimization) method. Finally, a visual RFID-enabled Push/Pull control experiment platform is built. It has potential to the practical applications of RFID-enabled Push/Pull control strategy.Research contents of this dissertation are presented as follows:(1) RFID-enabled electronic kanban system is developed and realized based on the RFID. which can count and locate the inventory products and goods transited precisely. The total design of the system and hardware realization is deeply studied. The key factors that affect the function of RFID are summarized through experiment test. The works metioned above provide the foudnation for RFID-enabled electronic Kanban system to play full role in the visualization of the multi-echelon inventory networks in supply chain.(2) Three-echelon inventory systems in supply chain are exemplified and eight kinds of RFID-enabled hybrid Push/Pull control strategies are designed based on the RFID-enabled electronic Kanban system. The structural characteristics of the supply chain and the functions of node enterprises in different echelons and drawing lessons from effective Push/Pull hybrid control strategy in the single factory multi-stage production storage system are considered in the strateties designs. The mathematical models of these strategies is established, and the various RFID-enabled Push/Pull hybrid strategies and (r, Q) strategy are compared by simulation experiment in the traditional performance assessment indexes framework.(3) The performance assessment indexes system of multi-echelon inventory control in supply chain is designed. The simulation platform of the multi-echelon inventory control is developed. The various of inventory control strategies are compared on the simulation platform adopting the designed performance assessment indexes system.(4) The simulation-based optimization with PSO as its upper level optimization algorithm and the simulation platform are developed. It is adopted to optimize these RFID-enabled hybrid Push/Pull control strategies. Through reiterative computational experiments the optimal RFID-enabled hybrid Push/Pull control strategy are found finally.(5) Based on the above four-research content, the visual RFID-enabled Push/Pull control experiment platform is established. It has potential to the practical applications of RFID-enabled Push/Pull control strategy.