João Alcântara

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In the current paper, we reexamine the connection between formal argu-mentation and logic programming from the perspective of semantics. We observe that one particular translation from logic programs to instantiated argumentation (the one described by Wu, Caminada and Gabbay) is able to serve as a basis for describing various equivalences between logic(More)
In this work, paraconsistent answer sets for extended disjunctive logic programs are presented as a fully declarative approach. In order to do so, we introduce a frame-based semantics. Frames are a powerful and elegant tool which have been used to characterise and study substructural logics. Unlike the original definition, no kind of syntactic(More)
In this paper, we introduce a paraconsistent extension of Rough Description Logics which allows the representation of incomplete and contradictory concepts, as well as the lower and upper approximations of these kinds of concepts. Furthermore, we use the notions of approximations, which can be applied successively, to make restrictions or relaxations in the(More)
In this paper we develop a new semantics for disjunctive logic programs, called Well-Founded Semantics with Disjunction (WFS d), by resorting to a fixed point-based operator. Coinciding with the Well-Founded Semantics (WFS) for normal logic programs, our semantics is uniquely defined for every disjunctive logic program. By exploring examples , we show WFS d(More)
In this work, we present Paraconsistent Well-Founded Semantics with eXplicit negation (WFSXp) by introducing a frame-based semantics. As far as we know, this is the first time that a declarative approach for WFSXp is effectively characterised in terms of a model theory. Dismissing usual techniques based on immediate consequence operators, our definition(More)
Purpose. To report a case of successful thrombolysis performed in a patient with an incidental unruptured intracranial aneurysm and review the literature. Case Report. Patient admitted for ischemic stroke due to left posterior cerebral artery occlusion, with an incidental right middle cerebral artery aneurysm, who underwent treatment with tissue plasminogen(More)