Research On Production-Inventory Management Strstegy Under Step-Change Demand Disruption

With rapid development of science technology and globalization, supply chains gradually evolve into complex network systems all over the world. Traditional supply chain management ideas, e.g. Lean Production, Global Sourcing, Business Outsourcing, etc., emphasize improving cost efficiency under normal operation, while making modern complex supply chain networks more and more vulnerable to disruption risks in the uncertain operation environment. Many serious disruption cases have brought supply chain security problems into the forefront of public attention. Supply chain inventory management under demand disruption is proposed to lower the loss of supply chains and quickly recover from disruptions. Considering supply chains under demand disruption and focusing on satisfy customer demand and lower the loss of supply chain, we study supply chain inventory management strategies in this dissertation.Without considering the order lead time, a state space model for a supply chain system consisting of a supplier and a retailer is developed based on nonlinear dynamics theory. The stability of the supply chain system is analyzed. Two distinct supply chain volatility metrics are introduced to measure the ability to respond to a demand disruption. Numerical and analytical results suggest the relationship between this two metrics with demand forecasting parameters, the adjustment range between net stock and desired net stock, the strength of this demand disruption.With considering the order lead time, a state space model for a supply chain system consisting of a supplier and a retailer is developed based on nonlinear dynamics theory. The stability of the supply chain system is analyzed. Convergence time and order amplification are used as supply chain volatility metrics to measure the ability to respond to a demand disruption. In order to converge to the equilibrium point as soon as possible, we study the optimal inventory management strategy. Numerical and analytical results suggest the relationship between this two metrics with demand forecasting parameters, the adjustment range between net stock and desired net stock, the strength of this demand disruption.The production-inventory management strategy of contingent rerouting from adjusting production rate side is studied. Based on adujusting production rate which is one of the key factors affecting the product output, production-inventory model is developed. Conditional on the type, magnitude and duration of demand disruptions, changes may be called to revise the original production plan. We analyse different disruption scenarios and propose optimal production-inventory models for products facing demand disruption. To lower the cost, we optimise the production rate, purchasing times and order quantity for the manufacturer. Numerical experiments are conducted to examine the influences of disruption time and magnitude on optimal production and purchasing decisions.Considerring both production disruption and demand disruption, the production-inventory management strategy of contingent rerouting from adjusting production time side is studied. Based on adujusting production time which is the other key factor affecting the product output, production-inventory model is developed. Conditional on the type, magnitude and duration of disruptions, changes may be called to revise the original production plan. We analyse different disruption scenarios and propose optimal production-inventory models for products facing demand and production disruptions. To lower the cost, we optimise the production run time, purchasing times and order quantity for the manufacturer. Numerical experiments are conducted to examine the influences of disruption time and magnitude on optimal production and purchasing decisions.This study is beneficial to improve the supply chain inventory management theory, help enterprises to enhance their ability to fight against and recover from disruptive events, and maintain the healthy, sustained and steady development of social economy under impacts of disruptive events.