
 Theory Seminar, P.Sewell, 97 06 27 (Site not responding. Last check: 20071018) 
  In this work I consider an example application of the picalculus, the programming language Pict of Pierce and Turner, primarily in order to see how far it is possible to argue, from facts about the application, that some model is the most appropriate. 
  An operational model can be given, reflecting this discussion, of the interactions between a Pict implementation (considered as the abstract behaviour of a C program) and its environment (modelling an operating system and user). 
  This leads to definitions of a class of abstract machines and abstract machine correctness, using an adapted notion of testing, and to a proof that a sample abstract machine is indeed correct. 
 www.cl.cam.ac.uk /Research/TSG/Seminars/PSewell2.html (223 words) 
