Several issues in model evolution and some papers on them

In MDSD, as systems evolve, models, meta-models will also need to be modified. Some concepts in traditional software engineering need to be introduced to MDSD. Here's (a list of some related topics and some research papers on them.)

1. Model version control
( Merging graph-like object structures by Albert Zundorf,Jorg P.Wadsack and Ingo Rockel)

2. Model transformation testing
( A Testing Framework for Model Transformations by Yuehua Lin,Jing Zhang,and Jeff Gray)

3. Model validation maintenance in the process of meta-model evolution
( A Generative Approach to Model Interpreter Evolution by Jing Zhang,Jeff Gray,and Yuehua Lin)

1. Definition of model difference
What is the difference between two models? The answer could be quite different based on differente abstraction levels and in different contexts. To answer this question properly is the first step to an effective and efficient model comparison mechanism.

2. Model representations
Models can be stored in many forms.

• Tool specific internal data structure
  Models defined in MOF-based(or EntityRelationship-based,Class Diagram-based) formalisms can be stored as typed attributed graphs. These are implemented as tool-specific data structure. APIs are provided for visiting the model elements.
  


• XML form
  Models can also be stored as XML files. XMI by OMG provides the standard for representing UML diagrams in XML.

3. Algorithms to calculate the model difference
Based on differente model representations, there're different algorighms to calculate the difference.

• Algorithms based on tool specific internal data structure
  Merging graph-like object structures by Albert Zundorf,Jorg P.Wadsack and Ingo Rockel
  


• Algorithms based on XML form
  X-Diff:An Effective Change Detection Algorithm for XML Documents by Yuan Wang, David J.DeWitt and Jin-Yi Cai
  Detecting Changes in XML Documents by Gregory Cobena, Serge Abiteboul and Amelie Marian
  
  
• Algorithms independent of model representations
  Difference and Union of Models by Marcus Alanen and Ivan Porres
  Change Detection in Hierarchically Structured Information by Sudarshan S. Chawathe, Anand Rajaraman, Hector Garcia-Molina, and Jennifer Widom
  

4. Representation of the model difference
How to represente the model difference? Should it be a XML file? a graph? or other forms? This question is especially important for the efficient use of the model comparison results.