中文摘要：

在供应风险环境下,研究不同采购策略（单源或双源）对制造商的产品价格与质量竞争的影响。引入包含Hotelling模型和质量水平的效用函数,构建由两个制造商组成的二维竞争模型,得到均衡情形下的产品价格与质量水平,并给出均衡唯一存在的条件。研究表明：最终均衡结果与制造商的产品质量成本有关,与选择单源采购策略的制造商相比,当产品质量成本较小时,选择双源采购策略的制造商会采用低质、低价的竞争策略;当产品质量成本较大时,选择双源采购策略的制造商会采用高质、高价的竞争策略。借助敏感性分析说明：当质量成本较小时,双源采购策略会加剧制造商之间的竞争;当质量成本较大时,双源采购策略会削弱制造商之间的竞争。制造商在质量成本较大时选择双源采购策略对自己更有利。

英文摘要：

This study investigates the effect of different sourcing strategies（single or dual sourcing）on manufactures＇ horizontal and vertical competition.Based on the utility function comprising the Hotelling model and quality,we establish a two-dimensional differentiation model with two competing manufacturers,and find the pricing and quality strategies of each manufacturer in equilibrium as well as the conditions under which the equilibrium uniquely exists.The result shows that the pricing and quality strategies depend on quality cost of the product;compared with the manufacturer who adopts single-sourcing strategy,the manufacturer who adopts dual-sourcing strategy will choose lower price and quality if quality cost is relatively small,otherwise will choose higher price and quality.Moreover,through a numerical examination,we observe that adopting dual-sourcing strategy can intensify the competition between two manufacturers if quality cost is relatively small,and can mitigate this competition if quality cost is relatively large.Hence,manufacturers will benefit more from dual-sourcing strategy when quality cost is relatively large.