Using the situation calculus as underlying formalism for specifying database updates as proposed by Raymond Reiter, a semantical notion of relevance of entries in tables to other entries is introduced. Also a semantical notion of relevant action is provided. Some properties of these semantical notions are investigated. In particular, they are compared with syntactical deenitions of relevance th...

As I began reviewing biographical information about Dr. Raymond C. Bartlett in preparation for writing this brief biographical feature, it suddenly occurred to me that this was a rare opportunity to think about the trajectory of my own career path and the influence that some of the visionary clinical microbiologists such as Dr. Raymond Bartlett had on the way clinical microbiology laboratories ...

Discussion of a radiation dose calculation example demonstrates various expressive limitations of the reenement calculus, particularly for systems with continuous variables. A liberalization of reenement, called retrenchment, is proposed, which will support an analogous formal development calculus. Useful concrete system behaviour can be speciied outside the domain of pure reenement, in particu...

Raymond and Beverly Sackler Faculty of Exact Sciences The Blavatnik School of Computer Science

This paper investigates a consistent version cwaS Reiter’s closed world assumption cwa. It proves (cf. theorem 4.11) that for purely relational languages cwaS is ∀-complete with respect to minimal semantics, i.e. for every ∀-sentence φ and for every ∀-theory Σ, φ ∈ cwaS(Σ) iff Σ `min φ. Moreover, it relates cwaS to other known syntactic characterization of minimal semantics: Minker’s GCWA.