Results 1 - 10 of 30,473

Practical Reasoning for Expressive Description Logics

by Ian Horrocks, Ulrike Sattler, Stephan Tobies , 1999
"... . Description Logics (DLs) are a family of knowledge representation formalisms mainly characterised by constructors to build complex concepts and roles from atomic ones. Expressive role constructors are important in many applications, but can be computationally problematical. We present an algorithm ..."
Abstract - Cited by 354 (65 self) - Add to MetaCart
. Description Logics (DLs) are a family of knowledge representation formalisms mainly characterised by constructors to build complex concepts and roles from atomic ones. Expressive role constructors are important in many applications, but can be computationally problematical. We present

Reasoning in Expressive Description Logics

by Diego Calvanese, Giuseppe De Giacomo, Daniele Nardi, Maurizio Lenzerini , 2000
"... ..."
Abstract - Cited by 109 (16 self) - Add to MetaCart
Abstract not found

Using an Expressive Description Logic: FaCT or Fiction?

by Ian R. Horrocks - In Proc. of KR-98 , 1998
"... Description Logics form a family of formalisms closely related to semantic networks but with the distinguishing characteristic that the semantics of the concept description language is formally defined, so that the subsumption relationship between two concept descriptions can be computed by a suitab ..."
Abstract - Cited by 273 (50 self) - Add to MetaCart
suitable algorithm. Description Logics have proved useful in a range of applications but their wider acceptance has been hindered by their limited expressiveness and the intractability of their subsumption algorithms. This paper addresses both these issues by describing a sound and complete tableaux

Optimisation Techniques for Expressive Description Logics

by Ian Horrocks , 1997
"... This report describes and evaluates optimisation techniques for a tableaux based satisfiability testing algorithm used to compute subsumption in Grail, an expressive description logic. Five techniques are studied in detail: normalisation and encoding, indexing, semantic branching, dependency directe ..."
Abstract - Cited by 11 (1 self) - Add to MetaCart
This report describes and evaluates optimisation techniques for a tableaux based satisfiability testing algorithm used to compute subsumption in Grail, an expressive description logic. Five techniques are studied in detail: normalisation and encoding, indexing, semantic branching, dependency

Conservative extensions in expressive description logics

by Carsten Lutz, Dirk Walther, Frank Wolter - In Proc. of IJCAI-2007 , 2007
"... Abstract The notion of a conservative extension plays a central role in ontology design and integration: it can be used to formalize ontology refinements, safe mergings of two ontologies, and independent modules inside an ontology. Regarding reasoning support, the most basic task is to decide whethe ..."
Abstract - Cited by 99 (17 self) - Add to MetaCart
whether one ontology is a conservative extension of another. It has recently been proved that this problem is decidable and 2ExpTime-complete if ontologies are formulated in the basic description logic (DL) ALC. We consider more expressive DLs and begin to map out the boundary between decidable

Practical reasoning for very expressive description logics

by Ian Horrocks - Journal of the Interest Group in Pure and Applied Logics 8 , 2000
"... Description Logics (DLs) are a family of knowledge representation formalisms mainly characterised by constructors to build complex concepts and roles from atomic ones. Expressive role constructors are important in many applications, but can be computationally problematical. We present an algorithm t ..."
Abstract - Cited by 185 (22 self) - Add to MetaCart
Description Logics (DLs) are a family of knowledge representation formalisms mainly characterised by constructors to build complex concepts and roles from atomic ones. Expressive role constructors are important in many applications, but can be computationally problematical. We present an algorithm

Optimising Terminological Reasoning for Expressive Description Logics

by Dmitry Tsarkov, Ian Horrocks, Peter F. Patel-schneider , 2007
"... Abstract. Tableau algorithms are currently the most widely-used and empirically the fastest algorithms for reasoning in expressive Description Logics, including the important Description Logics SHIQ and SHOIQ. Achieving a high level of performance on terminological reasoning in expressive Descriptio ..."
Abstract - Cited by 9 (1 self) - Add to MetaCart
Abstract. Tableau algorithms are currently the most widely-used and empirically the fastest algorithms for reasoning in expressive Description Logics, including the important Description Logics SHIQ and SHOIQ. Achieving a high level of performance on terminological reasoning in expressive

A semantic similarity measure for expressive description logics

by Claudia d'Amato, Nicola Fanizzi, Floriana Esposito - PROCEEDINGS OF CONVEGNO ITALIANO DI LOGICA COMPUTAZIONALE, CILC05 , 2005
"... Abstract. A totally semantic measure is presented which is able to calculate a similarity value between concept descriptions and also between concept description and individual or between individuals expressed in an expressive description logic. It is applicable on symbolic descriptions although it ..."
Abstract - Cited by 35 (9 self) - Add to MetaCart
Abstract. A totally semantic measure is presented which is able to calculate a similarity value between concept descriptions and also between concept description and individual or between individuals expressed in an expressive description logic. It is applicable on symbolic descriptions although

Role conjunctions in expressive description logics

by Birte Glimm, Yevgeny Kazakov , 2008
"... We show that adding role conjunctions to the Description Logics (DLs) SHI and SHOIF causes a jump in the computational complexity of the standard reasoning tasks from ExpTime-complete to 2ExpTime-complete and from NExpTime-complete to N2ExpTime-hard respectively. We further show that this increase ..."
Abstract - Cited by 4 (1 self) - Add to MetaCart
We show that adding role conjunctions to the Description Logics (DLs) SHI and SHOIF causes a jump in the computational complexity of the standard reasoning tasks from ExpTime-complete to 2ExpTime-complete and from NExpTime-complete to N2ExpTime-hard respectively. We further show

Beth Definability in Expressive Description Logics

by Balder Ten Cate, Enrico Franconi, Inanç Seylan - PROCEEDINGS OF THE TWENTY-SECOND INTERNATIONAL JOINT CONFERENCE ON ARTIFICIAL INTELLIGENCE , 2011
"... The Beth definability property, a well-known property from classical logic, is investigated in the context of description logics (DLs): if a general L-TBox implicitly defines an L-concept in terms of a given signature, where L is a DL, then does there always exist over this signature an explicit def ..."
Abstract - Cited by 2 (1 self) - Add to MetaCart
The Beth definability property, a well-known property from classical logic, is investigated in the context of description logics (DLs): if a general L-TBox implicitly defines an L-concept in terms of a given signature, where L is a DL, then does there always exist over this signature an explicit
Results 1 - 10 of 30,473