Business item modeling refinements - business items can be defined without all of the detail and be refined later with more details such as new attributes 业务项目建模细化可以不定义业务项目的所有细节，随后将其细化成更多的细节，如新的属性。
2.
Chen , t . y . , 1987 . 05 , ” finite element model refinement using modal analysis data , ” ph . d . dissertation , the university of texas at arlington 邬诗贤、陈定宇、林忠志, 1989 . 06 , “设计参数对自然振动频率之影响-频率灵敏度分析, ”金属工业中心委?研究计划报告
