Results 251 to 260 of about 938,794 (293)

Representability in Default Logic

Logic Journal of the IGPL, 2005
Summary: A default theory can be seen as a way for representing a set of formulae, i.e., its extensions. In this paper, we characterize the sets of formulae that can be expressed by a default theory according to various semantics: justified, constrained, rational, cumulative, QDL, CADL, and two semantics with priorities.
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Towards a classification of defaults logics

Journal of Applied Non-Classical Logics, 1997
ABSTRACT Reiter's default logic is one of the most prominent and well-studied approaches to nonmonotonic reasoning. Its evolution has resulted in diverse variants enjoying many interesting properties. This process however seems to be diverging because it has led to default logics that are difficult to compare due to different formal characterizations ...
Linke, Thomas, Schaub, Torsten (Prof. Dr.)   +1 more
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Prioritizing Default Logic

2000
In nonmonotonic reasoning conflicts among defaults are ubiquitous. For instance, more specific rules may be in conflict with more general ones, a problem which has been studied intensively in the context of inheritance networks (Poole, 1985; Touretzky, 1986; Touretzky et al., 1991).
Gerhard Brewka, Thomas Eiter
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A tutorial on default logics

ACM Computing Surveys, 1999
Default logic is one of the most prominent approaches to nonmonotonic reasoning, and allows one to make plausible conjectures when faced with incomplete information about the problem at hand. Default rules prevail in many application domains such as medical and legal reasoning.
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A framework for default logics

1992
We present a general framework for default logics, which encompasses most of the existing variants of default logic. It allows us to compare those variants from a knowledge representation point of view. We then exploit this framework to generalize Brewka's work on cumulative default logic, and to give an operational definition of extensions.
Christine Froidevaux, Jérôme Mengin
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Temporalizing Epistemic Default Logic

Journal of Logic, Language and Information, 1998
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Wiebe van der Hoek, John-Jules Ch. Meyer, Jan Treur   +2 more
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Using default logic to enhance default logic: preliminary report

2008 IEEE International Conference on Information Reuse and Integration, 2008
This paper is about the fusion of multiple knowledge sources represented using default logic. More precisely, the focus is on solving the problem that occurs when the standard-logic knowledge parts of the sources are contradictory, as default theories trivialize in this case. To overcome this problem, several candidate policies are discussed.
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Default Logic as Dynamic Doxastic Logic

Erkenntnis, 1999
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Hierarchical default logic

1991
We present a formal framework for ordered default reasoning which has desirable mathematical properties yet is relatively simple and can be implemented using standard theorem provers. By expressing default logic as a relation from theories to extensions we are able to formalise Brewka's prioritized default logic as a composite relation.
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Modal logic for default reasoning

Annals of Mathematics and Artificial Intelligence, 1990
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
V. Wiktor Marek, Miroslaw Truszczynski
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