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Description Logics for Information Integration [chapter]

Diego Calvanese, Giuseppe De Giacomo, Maurizio Lenzerini
2002 Lecture Notes in Computer Science  
Following the work in [32, 16, 40] , in this paper we use a formalism of the family of Description Logics to specify mediated schemas.  ...  A logic of the Description Logics family is used to model the information managed by the integration system, to formulate queries posed to the system, and to perform several types of automated reasoning  ...  Vardi, who contributed to several ideas illustrated in the chapter.  ... 
doi:10.1007/3-540-45632-5_2 fatcat:z4wh7vztsvbvrdd36frnyman7a

Guest editor's introduction: Logic-based heterogeneous information systems

Raghu Ramakrishnan, V.S. Subrahmanian
2000 The Journal of Logic Programming  
The view relations are the relations available for querying by users, and queries are answered by automatically rewriting them to refer only to source relations.  ...  In this special issue of the Journal of Logic Programming, we highlight the use of logic in integrating distributed repositories.  ...  ing produce answers that belong to the query, and shows how to produce such`m aximally contained'' queries through rewriting, taking into account integrity constraints and query binding patterns; in general  ... 
doi:10.1016/s0743-1066(99)00022-9 fatcat:hnjqtyinjjb7ze5jdrbpog6gem

Introduction to logical information systems

S. Ferré, O. Ridoux
2004 Information Processing & Management  
Logical Information Systems (LIS) use logic in a uniform way to describe their contents, to query it, to navigate through it, to analyze it, and to maintain it.  ...  In fact, a logic plays in a LIS the role of a schema in data-bases.  ...  It should contain simple formulas subsuming logical descriptions (in K), frequently used formulas (in queries), and more generally, every formulas that users expect to see in answers.  ... 
doi:10.1016/s0306-4573(03)00018-9 fatcat:kq2afgbavjd5vlvgrnauuay56a

Information Integration and Computational Logic [article]

Yannis Dimopoulos, Antonis Kakas
2001 arXiv   pre-print
It attempts to evaluate the current and potential role of Computational Logic in this and suggests some of the problems where logic-based techniques could be used.  ...  Information from disparate heterogeneous sources often with no a-priori common schema needs to be synthesized in a flexible, transparent and intelligent way in order to respond to the demands of a query  ...  We would also like to thank the following colleagues who provided us with useful material and their views on the subject by answering a questionnaire that was sent to them: Stephanne Bressan, Stefano Ceri  ... 
arXiv:cs/0106025v1 fatcat:u275rpw5i5c3xg7jjn636y53um

Ontology-based Query Processing in a Dynamic Data Integration System

Mohammed Mahmudur Rahman
2013 Computer Science and Information Technology  
We define architecture used for Semantic Query Distribution and we formally discuss the problem of query rewriting inside our data integration framework.  ...  We begin by introducing Data integration systems (DIS), Ontologies and other preliminary concepts that will be used throughout the presentation.  ...  Description Logics has been defined to efficiently address the problem of query answering in Description Logics under constraints (exclusion dependencies and key constraints), we check the model composed  ... 
doi:10.13189/csit.2013.010303 fatcat:o4rh7pldqre6tle2khhcf4xnwu

Content-Based Retrieval Of Medical Images

Lilac A. E. Al-Safadi
2012 Zenodo  
The semantic structure, which is bound to logical structure, is composed of semantic objects with interrelationships in the various spaces in the radiographic image.  ...  The logical structure represents the overall organization of information.  ...  to answer query such us "Retrieve an X-ray image for a 40 years old male with Choroid plexus cyst".  ... 
doi:10.5281/zenodo.1082997 fatcat:75ojihsryzf3npeuw3gbn7l5by

An Ontology-based Mediation Architecture for E-commerce Applications [chapter]

O. Corcho, A. Gomez-Perez, A. Leger, C. Rey, F. Toumani
2003 Intelligent Information Processing and Web Mining  
The MKBEEM mediation system allows to fill the gap between customers queries (possibly expressed in a natural language) and diverse specific providers offers.  ...  ontology and sources descriptions layers.  ...  The complementary roles of these two complex logical reasoning constitutes the description logic core for query processing in the MKBEEM system.  ... 
doi:10.1007/978-3-540-36562-4_51 fatcat:hor6c2kbp5azzlblj65fp6l26y

Modular Generation of Relational Query Paraphrases

Michael Minock
2006 Research on Language and Computation  
Query containment and equivalence are decidable for this class and this property is exploited in the maintenance and use of a phrasal lexicon.  ...  The approach to describing queries is phrasal and is restricted to a class of queries that return only whole schema tuples as answers.  ...  may generate intensional descriptions (within the language Q ) of the certain answers of the query over the views.  ... 
doi:10.1007/s11168-006-9009-8 fatcat:g2v6rf2p5jbcja7tie3usu3j54

Inconsistency Management for Description Logic Programs and Beyond [chapter]

Thomas Eiter, Michael Fink, Daria Stepanova
2013 Lecture Notes in Computer Science  
Description logic programs are a declarative approach to access ontological knowledge bases through a query interface, and to combine the query results using rules that can be nonmonotonic.  ...  While recent progress has been made, several issues remain to be explored; among them is inconsistency management for generalizations of description logic programs, and in particular for HEX programs,  ...  Among them are nonmonotonic description logic programs (briefly dl-programs) [4] , which provide a declarative approach to access ontologies through a query interface and to combine the query results  ... 
doi:10.1007/978-3-642-39666-3_1 fatcat:soap77utd5fztmjjczc4fkqcli

Effective support of databases with ontological dependencies: Relational languages instead of description logics

L. A. Kalinichenko
2012 Programming and computer software  
compared to the description logics.  ...  The first part of the paper retraces the development of description logics intended for application in the database and information systems context, as well as experimental results of building of the "  ...  ACKNOWLEDGMENTS This work was supported in part by the Russian Foundation for Basic Research (project nos. 10 07 00342 a and 11 07 00402 a) and by the Presidium of the Russian Academy of Sciences (the  ... 
doi:10.1134/s0361768812060059 fatcat:aezozh4o6rctjft47p3uny4lnm

Query Answering over Complete Data with Conceptual Constraints

Nhung Ngo
2016 Proceedings of the 2016 on SIGMOD'16 PhD Symposium - SIGMOD'16 PhD  
We first study the complexity of query answering problem under description logic constraints in the presence of complete data and show that complete data makes query answering become harder than query  ...  Query answering over databases with conceptual constraints is an important problem in database theory.  ...  Therefore, it is necessary to consider the case of query answering with constraints written in some description logics.  ... 
doi:10.1145/2926693.2929899 dblp:conf/sigmod/Ngo16 fatcat:o6f6vjbbnbeyrn5vzv4kdu54ny

Rules and Queries with Ontologies: A Unified Logical Framework [chapter]

Enrico Franconi, Sergio Tessaris
2004 Lecture Notes in Computer Science  
The focus of this paper is in the context of Semantic Web (SW), but the approach can be applied in any Description Logics (DL) based system.  ...  In the last part, we will show how rules are strictly related to queries. We claim that any choice of rule language for the semantic web should clearly define its semantics.  ...  We are currently working on the specification of the OWL-Log rule-extended knowledge base language in the DL-Log approach.  ... 
doi:10.1007/978-3-540-30122-6_4 fatcat:2mylhvs45jekznakbhsswmazpi

Ontologies and databases

Enrico Franconi
2008 Proceedings of the VLDB Endowment  
◮ What is an Ontology ◮ (Description) Logics for Conceptual Modelling ◮ Querying a DB via a Conceptual Schema Ontologies and Databases: myths and challenges. E.  ...  OWL, Description Logics). ◮ Ontology languages are typically expressed by means of diagrams. ◮ Entity-Relationship schemas and UML class diagrams can be considered as ontologies.  ...  ◮ Partial DB assumption (or conceptual schema with exact views): complete information about some term appearing in the conceptual schema ◮ Standard DB technologies do not apply ◮ The query answering  ... 
doi:10.14778/1454159.1454218 fatcat:6c3hv6kjrzc33cadrrju3aonny

Ontologies and Data Management: A Brief Survey

Thomas Schneider, Mantas Šimkus
2020 Künstliche Intelligenz  
In order to align and complete data, systems may rely on taxonomies and background knowledge that are provided in the form of an ontology.  ...  This survey gives an overview of research work on the use of ontologies for accessing incomplete and/or heterogeneous data.  ...  Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long  ... 
doi:10.1007/s13218-020-00686-3 pmid:32999532 pmcid:PMC7497697 fatcat:zeskjfjrpvcojjh6q3yjzhlyci

Forthcoming papers

1995 Artificial Intelligence  
In particular we defined approximation techniques for: propositional logic, fragments of first order logic (concept description languages) and modal logic.  ...  We also want our logic to be useful to perform approximate reasoning in different contexts. We define a method for the approximation of decision reasoning problems based on multivalued logics.  ...  , efficient query answering (e.g., checking whether a set of constraints is consistent with the knowledge base or necessarily true in it) is practically very important.  ... 
doi:10.1016/0004-3702(95)90010-1 fatcat:afhan6uvwffxzitrp7wnajfchm
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