Differentiating diagnostic theories through constraints over an eight-valued logic
Francisco Azevedo, Pedro Barahona · 2000
. In this paper we address the issue of diagnosing propositional theories where only some components are observable. More specifically, the goal is to find tests that allow the differentiation of two alternative theories. This subject is addressed in the context of differential diagnosis of faulty gates in a VLSI circuit where the only observable findings are its input/output bits, but may be extended to other areas, namely in diagnosing a theory of an agent where knowledge about it is based on its response to external stimuli. To model these problems we developed an eightvalued logic that describes the dependency of the findings on the competing theories. Additionally, we implemented a constraint solver to handle this eight-valued logic domain, and to solve efficiently the problem of obtaining differentiating tests that allow the elimination of one of the alternative theories. We discuss the limitations of the currently more advanced techniques to handle disjunctiv...