Abstract: As model-driven techniques are matured and widely used,more and more models reflecting structures,behaviors and features of program have been produced in the process of software development.And models also preserve as important parts of software documentations.Among them,UML models are most widely used.Therefore,comprehension of UML models is thought as a good way to the comprehension of large-scale,highly complex software systems.One of the difficulties to comprehension of UML models is how to find and locate effectively a certain structural feature of model fragments from a large number of complex models.Fortunately,the wide application of design patterns provides an important clue for us to understand and locate model quickly and efficiently.This paper aimed to analyze and understand the structural features of design patterns in order to identify design patterns in UML models.In this way,the purpose of understanding software system flexibly and efficiently can be achieved.

Key words: Model query technology,Unified modeling language,Information extraction,Design patterns