中文摘要：

为从知识库中检索相似工程更改案例，提出了一种聚合更改特征相似度计算工程更改相似度的方法．针对工程更改类别属于产品或零件外形更改的情况，提出更改特征概念，建立工程更改特征数据模型；分析工程变更影响与工程更改特征的关系，给出更改特征位于不同存在模式下的工程更改相似度计算公式；通过开发的原型系统，实例验证了该相似度计算方法的可行性．

英文摘要：

In order to retrieve similar engineering change （EC） cases from a knowledge bose, this paper proposed an approach that aggregated the similarities of change features （CFs） to compute the similarity between engineering changes （ECs）. First, the concept of change feature was proposed and the engineer- ing change feature data model （ECFDM） was constructed when an engineering change （EC） category be- longed to the products or parts alteration in shape. Next, the relation between the impact of change effect and change features was analyzed, and the similarity measures between ECs were given in various modes of change features. Finally, a case was provided to verify the feasibility of the similarity calculation method with a developed prototype.