中文摘要：

为了改善现有电子商务模型信任粒度过于粗糙，致使不能完成同一节点在不同领域的信任度计算问题，提出了一种P2P电子商务系统的细粒度信任模型（FGTM）。该模型阐述了领域之间的各种关系，提出了一种划分领域关系的方法，并引入了商品领域模型和领域信任度的概念，可以针对节点在任意商品领域的信任度进行度量，充分考虑领域之间的不同关系对信任度的影响。在信任度计算方面融合了多种影响因素，并给出了初始信任度的计算方法。最后，通过仿真实验验证了模型的有效性和可行性。

英文摘要：

In order to improve the ciccumstance that the trust grain of current e-commerce trust models is too rough to complete one node＇s trust computation in different domains, a novel fine-grain trust model for P2P e-commerce systems（FGTM） is presented. The model describes domain relation types and presents a method to divide them. The concepts of merchandise domain model and domain trust value are introduced into FGTM, the model can measure the trust value of peers in any merchandise domain and it can take full account of the impact of different relations between domains on the trust value of peers. On the computing of peer＇s trust value, it takes various factors into account and shows the computing method for the peer＇s initial trust value. Finally, the effectiveness and feasibility of this model are illustrated by the experiment.