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Feature Integration as an Operation of Theory Change

We formalise a relationship between two previously unconnected areas: theory change and feature interaction. This will provide an interesting new application area for the logic of theory change, and a theoretical underpinning for the feature interaction problem which has a largely practical basis. 
 
Update is an operation of theory change which is closely related to belief revision. The principal difference lies in the fact that belief revision models changing beliefs about a static world whereas update models a changing world. 
 
A feature is a unit of functionality which extends or modifies the behaviour of the system into which it is integrated. The feature interaction problem arises when two or more features interact, causing the system to exhibit unexpected, and often undesirable, behaviour. Many approaches to feature integration and interaction detection have been proposed. In this research we use a feature construct for the model checker SMV. 
 
We show that there is a strong connection between update and feature integration by, preliminarily, formulating SMV and the feature construct in propositional logic. We then go on to prove that the eight rationality postulates for update hold in the context of this theoretical formulation.