The Study Of Supply Chain Reliability Under Uncertain Demand

Today the world economy has showed significant integration features, enterprises are facing worldwide competition. Enterprises can no longer cope with such fierce competition if they depend on its own strength, so that a new mode of competition- the competition between different supply chains take place the competition between enterprises. while the key factor which decided the competitiveness of the supply chain is to improve their reliability. As competition becomes more intensified, and the market gradually turns into a buyer's market, enterprises need to pay more attention to customers' demand in the competition, while the main characteristics of customers' demand is of the uncertainty and diversity. Potential factors of the supply chain such as shortages can not be predicted scientificly and effectively, which will lead to lower competitiveness of the supply chain. So how to calculate the reliability of the supply chain becomes an important issue for multi-level supply chain networks.Firstly, this paper on the basis of the universal two-stage supply chain models composed of one supplier and several retailers put forward the calculation formulas of the supply chain entire reliability and branched chain reliability by using queuing theory and stochastic process.It provides a quantitative analysis tool to judge the reliability of the supply chain models composed of one supplier and several retailers.Then, it extends the research object to four-stage supply chain network model commonly used, which composed of component manufacturers, manufacture,distributors and retailers.By analyzing the four-stage supply chain network state and soluting the state balance equation it gets the steady-state probability of each state of four-stage supply chain as well as the calculation formulas of shortages probabilities of every enterprise on the chain . Using these probabilities it gives the entire reliability of the four-stage supply chain network as well as calculation formulas of reliability of every enterprise on each node, which provides a basis for judging the reliability of the four-stage supply chain network and coordinate control. Finally, it analyses the factors affecting the reliability of the supply chain, and gives the solutions to improve reliability of the supply chain.