Abstract: The sudden COVID-19 has had a great impact on the life and safety of our people and economic activities. As an important part of economic activities, supply chain has inevitably been affected. How to deal with the disruption of supply chain is an important challenge for enterprises. To reduce the impact of epidemic on the supply chain, this paper studies the manufacturer's procurement strategy at the risk of supply chain interruption. By introducing option contracts and analyzing factors such as the existence of alternative products in the market and the risk of supply interruption from the main supplier, four different scenarios are constructed to study procurement models composed of a low price unreliable main supplier, a high price reliable backup supplier, and a risk averse manufacturer under different scenarios. The four scenarios considered in this article are: Scenario 1: there is no substitute product in the market, and the main supplier does not experience supply interruption. Scenario 2: there is no substitute product in the market, and the main supplier experiences a supply interruption. Scenario 3: there are alternative products in the market, and the main supplier does not experience supply interruption. Scenario 4: there are alternative products in the market, and the main supplier experiences a supply interruption. Through the calculation of the model, the following conclusions are drawn:
(1)Market demand and procurement price are important factors affecting the manufacturer's optimal procurement volume. When the main supplier is interrupted, its reliability has also become a factor affecting the manufacturer's procurement.
(2)When the influencing factors such as market demand, reliability and cost of main suppliers change, the manufacturer's optimal procurement decision for main suppliers and the choice of emergency strategy for supply chain interruption will change.
(3)Only when the supply price of the main supplier is less than the difference between the sales price of the product sold by the manufacturer to the market and its own manufacturing cost,the manufacturer's optimal purchase quantity will increase with the increase in the option exercise price.
Finally, the numerical simulation model is used to study the manufacturer's optimal purchasing decision and the interaction between the parameters when the market demand, the manufacturer's purchasing price from the main supplier and the interruption risk of the main supplier take different values.
This article does not consider the possible relationship between manufacturers and manufacturers producing substitute products, that is, when studying the existence of manufacturers producing substitute products in the market, it does not consider the overlap of manufacturers. In the future, it can be considered that there are the same manufacturers among suppliers, that is, manufacturers produce both products they research and develop, and their substitute products, and study the decisions of manufacturers and suppliers at this time.

Key words: supply chain, partial disruption, backup supply, option contract

摘要： 突如其来的新冠肺炎疫情给我国人民的生命安全与经济活动带来了巨大的影响,供应链作为经济活动的重要组成部分,不可避免地遭受了冲击,如何应对供应链中断风险是企业面临的重要挑战。论文研究供应链中断风险情况下制造商采购策略,通过引入期权契约,构建不同情形下由低价不可靠的主供应商、高价可靠的后备供应商和风险规避制造商组成的采购模型,并得出以下结论:市场需求和采购价格是影响制造商最优采购量的重要因素,其中当主供应商出现中断时,其可靠性也是影响制造商采购的因素;当市场需求,主供应商的可靠性和成本等影响因素变化时,制造商对主供应商的最优采购决策、对供应链中断应急策略的选择都将发生变化;当且仅当主供应商的供应价格小于制造商向市场销售该产品销售价格和自身制造成本之差时制造商的最优采购量随着期权执行价格增加而增加。

关键词: 供应链, 部分中断, 后备供应, 期权契约