Katarina Britz

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The formal definition of abduction asks what needs to be added to a knowledge base to enable an observation to be entailed by the knowledge base. ABox abduction in description logics (DLs) asks what ABox statements need to be added to a DL knowledge base to allow an observation (also in the form of ABox statements) to be entailed. Klarman <i>et al</i> have(More)
To determine if prolonged fasting affects substrate utilization and endurance time, seven trained men exercised to exhaustion on a cycle ergometer at 50% maximum oxygen consumption (VO2max) in an overnight-fasted [postabsorptive (PA)] state and after a 36-h fast (F). Fasting produced significant elevations in the resting concentrations of blood free fatty(More)
In this paper we investigate the module-theoretic properties of ⊥− and >-reachability modules in terms of inseparability relations for the DL SRIQ. We show that, although these modules are not depleting or self-contained, they share the robustness properties of syntactic locality modules and preserve all justifications for an entailment.
We explore the notion of duality for defeasible entailment relations induced by preference orderings on states. We then show that such preferential entailment relations may be used to characterise Peircean inductive and abductive reasoning. Interpreting the preference relations as accessibility relations establishes modular Gödel-Löb logic as the modal(More)
Description logics are a well-established family of knowledge representation formalisms in Artificial Intelligence. Enriching description logics with non-monotonic reasoning capabilities, especially preferential reasoning as developed by Lehmann and colleagues in the 90’s, would therefore constitute a natural extension of such KR formalisms. Nevertheless,(More)
Modal logic is the foundation for a versatile and well-established class of knowledge representation formalisms in artificial intelligence. Enriching modal logics with non-monotonic reasoning capabilities such as preferential reasoning as developed by Lehmann and colleagues would therefore constitute a natural extension of such KR formalisms. Nevertheless,(More)
Objects can be said to be structured when their representation also contains their parts. While OWL in general can describe structured objects, description graphs are a recent, decidable extension to OWL which support the description of classes of structured objects whose parts are related in complex ways. Classes of chemical entities such as molecules,(More)