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Tractable reasoning and efficient query answering in description logics: The DL-Lite family

by Diego Calvanese, G. De Giacomo, Domenico Lembo, Maurizio Lenzerini, Riccardo Rosati - J. OF AUTOMATED REASONING , 2007
"... We propose a new family of Description Logics (DLs), called DL-Lite, specifically tailored to capture basic ontology languages, while keeping low complexity of reasoning. Reasoning here means not only computing subsumption between concepts, and checking satisfiability of the whole knowledge base, b ..."
Abstract - Cited by 497 (123 self) - Add to MetaCart
We propose a new family of Description Logics (DLs), called DL-Lite, specifically tailored to capture basic ontology languages, while keeping low complexity of reasoning. Reasoning here means not only computing subsumption between concepts, and checking satisfiability of the whole knowledge base

Textpresso: An Ontology-Based Information Retrieval and Extraction System for Biological Literature

by Hans-michael Müller, Eimear E. Kenny, Paul W. Sternberg - PLoS Biol , 2004
"... We have developed Textpresso, a new text-mining system for scientific literature whose capabilities go far beyond those of a simple keyword search engine. Textpresso’s two major elements are a collection of the full text of scientific articles split into individual sentences, and the implementation ..."
Abstract - Cited by 208 (14 self) - Add to MetaCart
search engine enables the user to search for one or a combination of these tags and/or keywords within a sentence or document, and as the ontology allows word meaning to be queried, it is possible to formulate semantic queries. Full text access increases recall of biological data types from 45 % to 95

OBSERVER: An Approach for Query Processing in Global Information Systems based on Interoperation across Pre-existing Ontologies

by E. Mena, V. Kashyap, A. Sheth, A. Illarramendi , 1996
"... The huge number of autonomousand heterogeneous data repositories accessible on the “global information infrastructure” makes it impossible for users to be aware of the locations, structure/organization, query languages and semantics of the data in various repositories. There is a critical need to co ..."
Abstract - Cited by 295 (36 self) - Add to MetaCart
The huge number of autonomousand heterogeneous data repositories accessible on the “global information infrastructure” makes it impossible for users to be aware of the locations, structure/organization, query languages and semantics of the data in various repositories. There is a critical need

in Ontology-Based Data Access

by Technische Universität Wien, Ognjen Savković
"... First of all, I would like to thank to my supervisor Prof. Diego Calvanese for his expert guidance, excellent comments and ideas that make this work possible. Also, I wish to thank to Prof. Steffen Hölldobler for his effort on leading the EMCL program, and providing me the significant funding, that ..."
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to share with them all my all goods and bads on my academic path. Using ontologies for the conceptual modeling of a domain of interest is becoming increasingly popular, since ontologies have a formal semantics based on Description Logics (DLs), and since they inherit from modeling languages (like UML

Ontology-based database access

by Diego Calvanese, Domenico Lembo, Maurizio Lenzerini, Antonella Poggi, Riccardo Rosati - in Proc. of SEBD 2007
"... Abstract. One of the most interesting usages of shared conceptualizations is ontology-based data access. That is, to the usual data layer of an information system we superimpose a conceptual layer to be exported to the client. Such a layer allows the client to have a conceptual view of the informati ..."
Abstract - Cited by 14 (5 self) - Add to MetaCart
Abstract. One of the most interesting usages of shared conceptualizations is ontology-based data access. That is, to the usual data layer of an information system we superimpose a conceptual layer to be exported to the client. Such a layer allows the client to have a conceptual view

The Mastro System for Ontology-based Data Access

by Diego Calvanese, Domenico Fabio Savo , et al. , 2011
"... In this paper we present Mastro, a Java tool for ontology-based data access (OBDA) developed at the ..."
Abstract - Cited by 61 (19 self) - Add to MetaCart
In this paper we present Mastro, a Java tool for ontology-based data access (OBDA) developed at the

The Combined Approach to Ontology-Based Data Access

by R. Kontchakov, C. Lutz, D. Toman, F. Wolter, M. Zakharyaschev - PROCEEDINGS OF THE TWENTY-SECOND INTERNATIONAL JOINT CONFERENCE ON ARTIFICIAL INTELLIGENCE , 2011
"... The use of ontologies for accessing data is one of the most exciting new applications of description logics in databases and other information systems. A realistic way of realising sufficiently scalable ontology-based data access in practice is by reduction to querying relational databases. In this ..."
Abstract - Cited by 45 (5 self) - Add to MetaCart
The use of ontologies for accessing data is one of the most exciting new applications of description logics in databases and other information systems. A realistic way of realising sufficiently scalable ontology-based data access in practice is by reduction to querying relational databases

Ontology-Based Data Access and Constraint

by Frank Wolter
"... In recent years, the use of ontologies (=logical theories) to access instance data has become increasingly popular. The general idea is that an ontology provides a vocabulary or conceptual model for the application domain, which can then be used as an interface for querying instance data and to deri ..."
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and to derive additional facts [2, 6]. In this presentation, I will introduce ontology-based data access for ontologies given in description logics and investigate the following non-uniform complexity problem: what is the data complexity of conjunctive query answering for a fixed ontology? I will present

Ontology-Based Task Simulation

by Martin Raubal, Werner Kuhn - In Spatial Cognition and Computation , 2004
"... Information services assist people in their decision-making during the performance of certain tasks. In order to determine if a data source, which commits to a given ontology, can be employed for a service, the service provider needs to evaluate its usability and utility for the decision-making proc ..."
Abstract - Cited by 15 (4 self) - Add to MetaCart
-making process. We propose to do this by simulating with the ontologies the tasks to be supported by the service. Such a simulation needs to access data about entities based on the actions they afford and the events they participate in. This requires that ontologies include information about these affordances

Ontology-based data access: Ontop of databases

by Roman Kontchakov, Michael Zakharyaschev - In Proc. of ISWC , 2013
"... Abstract. We present the architecture and technologies underpinning the OBDA system Ontop and taking full advantage of storing data in relational databases. We discuss the theoretical foundations of Ontop: the tree-witness query rewriting, T-mappings and optimisations based on database integrity con ..."
Abstract - Cited by 33 (4 self) - Add to MetaCart
constraints and SQL features. We analyse the per-formance of Ontop in a series of experiments and demonstrate that, for standard ontologies, queries and data stored in relational databases, On-top is fast, efficient and produces SQL rewritings of high quality. 1
Results 1 - 10 of 1,433