The Optimization Of Supply Chain Facility Location In The Presence Of Disruption Risks

The practices has proved that the supply chain operation mode was an effective and efficient strategic tool which could improve and enhance enterprises competitive advantage by win-win cooperation. But because the supply chain networks become more open and scalable with the great change of competition environment, there is more and more apparent or potential threats could result in the supply chain network disruptions. The disruptions can not only bring short-term operating loss, namely higher transportation costs, delays in orders, inventory shortages, but also long-term negative impacts to the supply chain’s operating performance. Therefore, how to improve the capacity of a supply chain network to resist disruption risks has become a major field of supply chain research and attracted more and more research attentions.Facility location problem is a class supply chain optimization problem with crucial theoretical and wide practical background whose essence is to seek reasonable arrangements to complete the assigned task with the best results in some sense. Generally, the outside conditions are assumed certain when we design the supply chain optimizing models. In fact, the parameters estimated are usually inaccurate due to uncertainty of forecasts, measurement errors or other factors. Moreover, even all of the parameters are exactly known beforehand, it maybe disrupted for the possible emergencies yet. So, the robustness and reliability of a supply chain are studied in this dissertation systematically. One is the supply chain perform well with the failure of parts in it, the other is it robust optimization to enhance the abilities to resist disruption risks, while ensuring the entire supply chain disruptions do not occur, by relaxing parameter hypothesis, no matter inaccurate or missing.According to the research design of this dissertation, the facility location optimization problem was divided into technical optimization and system optimization first. The former focused on the facility location optimization problem from the perspective of mathematical model, while the later is a necessary continuation of above, it focused on analyzing what factors affect the facility location technology to achieve the goals of optimization, and then the corresponding countermeasures were put forwards according to the results of empirical analysis.In the part of technical optimization, we study the facility location optimization problem from two aspects:the first is the Reliability of a supply chain system which focused on the ability of a supply chain system could function well as a whole when some of the facilities disrupted of a supply chain network; the second is the Robustness of it which is the robust optimization to enhance the abilities to resist disruption risks, while ensuring the entire supply chain disruptions do not occur. Moreover, even all of the parameters of the optimization model are exactly known beforehand, the supply chain maybe also disrupted for some possible emergencies. Therefore, based on the premise that continued operation of a supply chain, we divided the disruption scenario into two cases:random disruption and nonrandom disruption. The former adopts mixed-integer nonlinear programming model to focus on discrete facility location problem whose validity was verified by a simulation example. And then, based on the theory promotion of former discrete model, the dissertation proposed a new research program that divided the target area according to honeycombed division, and the continuous approximation model was constructed to deal with plane continuous facility location problem. Accordingly, the in-depth robustness analysis was carried on to the main parameters of the model. Then, in view of the nonrandom disruption scenario, the dissertation constructed a two-stage dynamic game model based on the worst scenario to study the premeditated disruption problem. In this part, it analyzed the optimal strategy of the attacker and defender to study how to enhance the robustness and improve the reliability of a supply chain to ensure its effectiveness and efficiency.So, in the part of system optimization, based on the above technical optimization, the dissertation studied the performance evaluation of the facility location optimization problem further by means of structural equation model after we obtained the original data by questionnaire. Based on the empirical results and the enterprise field investigation, we summarized and refined some optimization countermeasures with distinct Chinese cultural characteristics.It’s a further extension of the traditional supply chain optimization theory that the dissertation studied the robust optimization of supply chain facility location in the presence of disruption risks by linking supply chain disruption risk and supply chain facility location. To some extent, this dissertation makes up some gaps in this field which with theoretical and practical significance to supply chain management.The innovations of the study are:1. Three basic assumptions to the theoretical framework of supply chain optimization was proposed:Separate Entity Assumption, Continuity Assumption, Strategic Planning+ Tactical Planning Assumption.2. Based on the premise that continued operation of a supply chain, the facilities were divided into reliable and unreliable facilities, and the introducing of disruption risk factor makes the study with more practical significance.3. The dissertation proposed a new research program that divided the target area according to honeycombed division which makes the study more scientific and advanced.