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Basic Description Logics
This chapter provides an introduction to Description Logics as a formal language for representing knowledge and reasoning about it. It first gives a short overview of the ideas underlying DescriptionExpand
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The Complexity of Concept Languages
Abstract A basic feature of Terminological Knowledge Representation Systems is to represent knowledge by means of taxonomies, here called terminologies, and to provide a specialized reasoning engineExpand
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Evolution of DL-Lite Knowledge Bases
We study the problem of evolution for Knowledge Bases (KBs) expressed in Description Logics (DLs) of the DL-Lite family. DL-Lite is at the basis of OWL 2 QL, one of the tractable fragments of OWL 2,Expand
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An Epistemic Operator for Description Logics
Abstract Description logics (also called terminological logics, or concept languages) are fragments of first-order logic that provide a formal account of the basic features of frame-based systems.Expand
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Rewriting aggregate queries using views
We investigate the problem of rewriting queries with aggregate operators using views that may or may not contain aggregate operators. A rewriting of a query is a second query that uses viewExpand
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Subsumption algorithms for concept languages
We investigate the subsumption problem in logic-based knowledge representation languages of the KL-ONE family and give decision procedures. All our languages contain as a kernel the logicalExpand
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The Relational Grid Monitoring Architecture: Mediating Information about the Grid
We have developed and implemented the Relational Grid Monitoring Architecture (R-GMA) as part of the DataGrid project, to provide a flexible information and monitoring service for use by otherExpand
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R-GMA: An Information Integration System for Grid Monitoring
Computational Grids are distributed systems that provide access to computational resources in a transparent fashion. Collecting and providing information about the status of the Grid itself is calledExpand
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Order-Sorted Equational Computation
Publisher Summary This chapter discusses order-sorted equational computation. Many-sorted equational logic is the basis for algebraic specifications, rewriting techniques, unification theory, andExpand
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Tractable Concept Languages
We present two concept languages, called PL1 and PL2 which are extensions of TC. We prove that the subsumption problem in these languages can be solved in polynomial time. Both languages include aExpand
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