12pm on Friday, January 19th 2007,  KB 2.15
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A logical framework for monitoring and evolving software components

Howard Barringer, Dov Gabbay and David Rydeheard

We present a revision-based logical framework fro modelling hierarchical 
assemblies of evolvable component systems. An evolvable component is a 
tight coupling of a pair of components, comprising a supervisor and a 
supervisee, with the supervisor able to both monitor and evolve its 
supervisee. An evolvable component pair is itself a component so may 
have its own supervisor, or may be encapsulated as a part of a larger 
component.

Components are modelled as logical theories containing actions which 
describe state revisions together with a program over the actions. 
Supervisor components are modelled as theories which are logically at a 
meta-level to their supervisee. Revision actions at the meta-level can 
describe theory changes in the supervisee at the object-level and 
correspond to various evolutionary changes in the supervisee component. 
We will outline the framework and show how it enables us to describe the 
architecture, logical structure and logical programming of evolvable 
systems.