Modelling and analysis of strategic supply chain management systems

This thesis is a research study on modelling and analysis of strategic supply chain management systems. In a comprehensive survey of the literature on supply chain modelling and analysis, we present and discuss the results according to three issues, namely supply chain network, supply chain uncertainties, and supply chain coordination.; First, in a strategic supply chain design model, we introduce logical constraints to include the constraints related to bills of materials (BOM). Reflecting intimate material supply relationships with vendors, the bottom level of BOM can be described as a list of specified quantities of materials or components supplied by different vendors. We can express BOM as logical rules such as “if product i will be produced in at least s of the proposed plants, then at least t of the candidate vendors must be selected”. This formulation of BOM constraints provides a reasonable way to capture the role of vendors in the strategic supply chain design model. We will show how BOM constraints are formulated in our proposed MIP model to assist in the selection of vendors, and how linear representation of logical constraints is developed. Logical constraints can also be used to represent the relationships among the main entities of a supply chain such as vendors, plants, and distribution centers. We will also show how these relationships are formulated as logical constraints.; Second, we study an optimal inventory policy for a two-stage supply chain, which includes a supplier and a retailer. The supplier orders from an unstable outer source, which means the supplier can't receive the placed order on time and its lead time is variable. Supplier's variable lead time is assumed to be identically distributed with mean and variance. The retailer faces customer demands which form a Poisson process with intensity λ. Each customer demand arrival brings a batch of Q units. Both of the supplier and retailer adopt periodic-review batch-ordering policies. We present a modelling framework to demonstrate the modelling analysis of supplier's lead time variability in this two-stage supply chain. We show the relationships between inventory costs and lead time variability. Comparing the results to the model with constant lead time, we can see that this variability can cause excess inventory. We also suggest further approaches in this topic about the reduction of the deficiency of lead time variability and the possible coordination mechanisms to reduce the variability.; Third, in a two-level decentralized supply chain, we present a study aimed at quantifying the benefits of information sharing-based supply chain partnerships. Based on a modelling framework, we introduce three levels of information integration for modelling the partnerships in a two-stage supply chain consisting of a single retailer and a single manufacturer, namely decentralized control, coordinated control and centralized control. We derive the optimal inventory policies for the manufacturer and the retailer under these three different information sharing scenarios. We show that increasing information sharing among the members in a decentralized supply chain will lead to Pareto improvement in the performance of the entire chain. Specifically, both of the manufacturer and the retailer can obtain benefits in terms of reductions in inventory levels and cost savings. (Abstract shortened by UMI.)...