Semantic Model Of Uml Models

The Unified Modelling Language(UML) is a graphic language for specifying, visualizing, constructing,and documenting the artifacts of software systems. The UML represents a collection of the best engineering practices that have been proven successful in the modelling of large and complex system. The UML has become the de-facto standard modelling language for the software development after adoption of the UML 1.1 proposal by the OMG membership in November 1997. Many organizations worldwide have already embraced the UML. These organizations will continue to encourage the use of the Unified Modelling Language by making the definitions readily available and by encouraging other methodologists, tool vendors, training organizations, and authors to adopt the UML.Different modelling diagrams are used at different stages of software development, and at different levels of abstraction. For example, use case diagram and class diagram are used for the static analysis, sequence diagram and activity diagram for behavioral analysis, and component diagram and deployment diagram for implementation. Under the multiple views of UML, the developers can decompose a software designinto smaller parts of manageable scales. However, several challenging issues inevitably arise from such a multi-view approach: Consistency: the models of various views need to be syntactically and semanti-cally compatible with each other. Transformation and evolution: a model must be semantically consistent with its refinement.