Robust Model And Optimization In Multiple Supplier Selection Considering Supply Disruption

In recent years, the using of the just-in-time mode of production in supply chain system has increased the vulnerability of the system’s internal environment, complexity and the uncertainty of the external environment. It has become an urgent problem for enterprises to prevent the supply disruption and deal with the impact of it. The related research literature on supply disruption presents a growing trend.In this thesis, we establish manufacturers ordering manufacturers ordering multi-product model, considering emergency inventory separately. The model involve a supply chain system consisted of a risk-preference manufacturer and multiple suppliers. As for manufacturer’s cost, we only consider the expected cost per units of risk-neutral manufacturer and the conditional value at risk of risk aversive manufacturers. In the model, two objects of supply chain are considered at the same time. We comparatively analyze supplier selection quantity under different disruption risk, the expected cost per units and the conditional value at risk. We use the value-at-risk and conditional value-at-risk as the way of the risk metrics to control the risk of supply disruption, and to make sure that we have selected the optimal combination of suppliers in the way of production order and how to allocate the orders.Meanwhile, a supplier selection model is built under the supply disruption’s probability uncertainty, the market demand uncertainty and the selling price uncertainty. We also build a robust model with the methods of the known probability discrete scenario analysis and range of uncertainty. Under the condition of the manufacturer’s profit, the minimization of manufacturer’s expected cost per units and conditional value at risk can resist certain uncertainty. Besides, simulation and analysis are conducted at the same time. After simulating and analyzing multi-product supplier selection models which both have different risk parameters under the situation of supply disruption, it is found that the number of suppliers that the manufactures choose will increase, if the risk parameter of manufactures increases. However, manufactures will give priority to the suppliers who have lower rate of supply disruption. If the number of the product ordered increases, they will also choose more suppliers. After simulating and analyzing robust design models under uncertainties, it is proved that robust models are "robust" when the uncertainty parameters (the supply disruption’s probability, the market demand and the selling price) within certain ranges.