The question we consider in this paper is: "When may a combination of (fine-grain) execution be contracted into an abstract (atomic) action execution? Our answer is basically: "When no observer can see the difference." This is worked out in detail by defining a notion of so-called coupled splitting/contracting simulation between systems which differ in the atomicity of their actions, and proving that this collapses to Parrow and Sjödin's coupled similarity when the systems are composed with an observer. We claim that this gives rise to a useful notion of refinement; we substantiate the claim on two (toy) examples.
|Publisher||University of Twente|
|Number of pages||44|
|Publication status||Published - 2000|
|Name||CTIT Technical Report series|
|Publisher||Centre for Telematics and Information Technology (CTIT)|