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How to Approximate Ontology-Mediated Queries [article]

Anneke Haga and Carsten Lutz and Leif Sabellek and Frank Wolter
2021 arXiv   pre-print
We introduce and study several notions of approximation for ontology-mediated queries based on the description logics ALC and ALCI.  ...  Our approximations are of two kinds: we may (1) replace the ontology with one formulated in a tractable ontology language such as ELI or certain TGDs and (2) replace the database with one from a tractable  ...  Introduction Ontology-mediated querying enriches database queries by an ontology, in this way providing domain knowledge and extending the language available for formulating queries.  ... 
arXiv:2107.05369v1 fatcat:xo5ckqfilzbude6n6benpznslm

How to Approximate Ontology-Mediated Queries

Anneke Haga, Carsten Lutz, Leif Sabellek, Frank Wolter
2021 Proceedings of the Eighteenth International Conference on Principles of Knowledge Representation and Reasoning   unpublished
We introduce and study several notions of approximation for ontology-mediated queries based on the description logics ALC and ALCI.  ...  Our approximations are of two kinds: we may (1) replace the ontology with one formulated in a tractable ontology language such as ELI or certain TGDs and (2) replace the database with one from a tractable  ...  Introduction Ontology-mediated querying enriches database queries by an ontology, in this way providing domain knowledge and extending the language available for formulating queries.  ... 
doi:10.24963/kr.2021/31 fatcat:7kjquzcj4bewpo2mdvktk6j4ku

TrOWL: Tractable OWL 2 Reasoning Infrastructure [chapter]

Edward Thomas, Jeff Z. Pan, Yuan Ren
2010 Lecture Notes in Computer Science  
We present the TrOWL infrastructure for transforming, reasoning, and querying OWL2 ontologies which uses novel techniques such as Quality Guaranteed Approximations and Forgetting to achieve this goal.  ...  Tools exist to reason over these ontologies and to answer queries over them, but there are no large scale infrastructures for storing, reasoning, and querying ontologies on a scale that would be useful  ...  We would also like to thank Stuart Taylor, Nophadol Jekjantuk and Yuting Zhao at the University of Aberdeen for their helpful discussion and other contributions.  ... 
doi:10.1007/978-3-642-13489-0_38 fatcat:5zf3fzq77rc5hj7n2krlxdbbam

Issues in the Design of a Pilot Concept-Based Query Interface for the Neuroinformatics Information Framework

Luis Marenco, Yuli Li, Maryann E. Martone, Paul W. Sternberg, Gordon M. Shepherd, Perry L. Miller
2008 Neuroinformatics  
an ontology.  ...  This paper describes a pilot query interface that has been constructed to help us explore a "concept-based" approach for searching the Neuroscience Information Framework (NIF).  ...  to querying the NIF arises because of the Database Mediator.  ... 
doi:10.1007/s12021-008-9035-9 pmid:18953674 pmcid:PMC2664632 fatcat:rsdcnggvmfavvdnpi4s4xqdciy

Ontology-based data integration methods: a framework for comparison

Agustina Buccell, Alejandra Cechich, Nieves R. Brisaboa
2005 Revista Colombiana de Computación  
An important feature is that all of them use, in some way, ontologies as the way to solve problems about semantic heterogeneity.  ...  Keywords: Data Integration, Ontology, Semantic Heterogeneity.  ...  Users formulate queries over the ontology of the mediator and it is the task of the mediator to choose the sources to be queried, and the query to be sent to each source.  ... 
doaj:2ba9f9a7c3d44c83b155e127e177ccbc fatcat:gdfg7pwaxjbkjeifj6geey2gkm

Query Rewriting or Ontology Modification? Toward a Faster Approximate Reasoning on LOD Endpoints

Naoki YAMADA, Yuji YAMAGATA, Naoki FUKUTA
2017 IEICE transactions on information and systems  
We employ an evolutionary approach to make such rewriting and modification of queries and ontologies based on the past-processed queries and their results.  ...  In this paper, for reducing query execution time on an inference-enabled LOD endpoint, we compare these two promising methods: query rewriting and ontology modification, as well as trying to combine them  ...  We presented that how a combination of query approximation and ontology modification could be effectively applied and how aggregating results on a cluster improved the runtime performance as well as the  ... 
doi:10.1587/transinf.2016agp0010 fatcat:j3bjvn273zgghpizdzbl4skiia

The KRAFT Architecture for Knowledge Fusion and Transformation [chapter]

Alun Preece, Kit Hui, Alex Gray, Philippe Marti, Trevor Bench-Capon, Dean Jones, Zhan Cui
2000 Research and Development in Intelligent Systems XVI  
The architecture uses constraints as a common knowledge interchange format, expressed against a common ontology.  ...  The fused knowledge is then used to solve some problem or deliver some information to a user. Problem-solving in KRAFT typically exploits pre-existing constraint solvers.  ...  We would like to thank Mike Shave and Jean-Christophe Pazzaglia for their comments on an earlier draft of this paper.  ... 
doi:10.1007/978-1-4471-0745-3_2 fatcat:3qcsz2djvbebnpdda2ljrfwthm

Configuring Intelligent Mediators Using Ontologies [chapter]

Gennaro Bruno, Christine Collet, Genoveva Vargas-Solar
2006 Lecture Notes in Computer Science  
This paper presents a new intelligent mediators configuration approach which exploits high expressive description logics to represent metadata, and reasoning tasks in order to build more flexible mediation  ...  A configured mediator can therefore be adapted in order to build knowledge-based mediation systems with an arbitrary architecture.  ...  Moreover, the knowlege-based query processing allows to enable approximative as well as partial query plans generation.  ... 
doi:10.1007/11896548_41 fatcat:kh5vpfbv3bet3lu77mzoewv5hy

The KRAFT architecture for knowledge fusion and transformation

A. Preece, K. Hui, A. Gray, P. Marti, T. Bench-Capon, D. Jones, Z. Cui
2000 Knowledge-Based Systems  
The architecture uses constraints as a common knowledge interchange format, expressed against a common ontology.  ...  The fused knowledge is then used to solve some problem or deliver some information to a user. Problem-solving in KRAFT typically exploits pre-existing constraint solvers.  ...  We would like to thank Mike Shave and Jean-Christophe Pazzaglia for their comments on an earlier draft of this paper.  ... 
doi:10.1016/s0950-7051(00)00052-6 fatcat:6udxrhwl3vbbdk2s7zhexv6kxy

Towards a Semantic Integration of Medical Relational Databases by Using Ontologies: A Case Study [chapter]

Tom Deray, Pieter Verheyden
2003 Lecture Notes in Computer Science  
We will demonstrate how this can be done by means of a case study, and how the coupling result can be deployed to query a relational database at the ontology level.  ...  Next to that, we will introduce a coupling language, and a discussion on how to integrate the language in two ontology models.  ...  We also want to thank Pieter De Leenheer for providing valuable feedback on an earlier version of this report.  ... 
doi:10.1007/978-3-540-39962-9_25 fatcat:nrg3e776fvh5bkl5limqb2jbbi

Towards a Mediator Based on OWL and SPARQL [chapter]

Konstantinos Makris, Nikos Bikakis, Nektarios Gioldasis, Chrisa Tsinaraki, Stavros Christodoulakis
2009 Lecture Notes in Computer Science  
SPARQL queries submitted to the Mediator are decomposed and reformulated to SPARQL queries to the federated sites. The evaluated results return to the Mediator.  ...  The Mediator supports mappings between the OWL Ontology of the Mediator and the other ontologies in the federated sites.  ...  SPARQL [3] queries over the Mediator are decomposed and reformulated to be submitted over the federated sites. The SPARQL queries are locally evaluated and the results return to the Mediator site.  ... 
doi:10.1007/978-3-642-04754-1_34 fatcat:7juggrh74zc5tbpaegceabqxia

Designing a Federated Multimedia Information System on the Semantic Web [chapter]

Richard Vdovjak, Peter Barna, Geert-Jan Houben
2003 Lecture Notes in Computer Science  
In particular, it refines the existing methodology by presenting an explicit RDFS-based integration model and explains how the mediator uses this model to obtain query results.  ...  The issue of a user-friendly front-end is addressed by introducing our interface for browsing and querying RDFS-based ontologies.  ...  In particular, it refines the existing methodology by presenting an explicit RDFS-based integration model, and explains how the mediator uses this model to obtain query results.  ... 
doi:10.1007/3-540-45017-3_25 fatcat:sonmiukb5rdwrc6vcdchjfwp3i

Managing scientific data: From data integration to scientific workflows* [chapter]

Bertram Ludäscher, Kai Lin, Shawn Bowers, Efrat Jaeger-Frank, Boyan Brodaric, Chaitan Baru
2006 Special Paper 397: Geoinformatics: Data to Knowledge  
The core idea of semantic mediation is to augment database mediators and query evaluation algorithms with appropriate knowledge-representation techniques to exploit information from shared ontologies.  ...  Semantic mediation relies on semantic data registration, which associates existing data with semantic information from an ontology.  ...  Data Integration In this section we first introduce the mediator approach to data integration and then show how it can be extended to a semantic mediation approach by incorporating ontologies as a knowledge  ... 
doi:10.1130/2006.2397(08) fatcat:sdi4qyg2d5f4pjxgn35kqzdyvi

Integrating Disparate Digital Libraries using the WASSIT Mediation Framework [chapter]

Faouzia Wadjinny, Imane Zaoui, Ahmed Moujane, Dalila Chiadmi
2011 Digital Libraries - Methods and Applications  
In mediation systems (Wiederhold, 1992) , data remains at the sources and queries to the integrated system need to be translated, at run time, into a sequence of sub-queries to the underlying data sources  ...  To deal with the interoperability problem, two solutions can be used: warehousing and mediation systems.  ...  In mediation systems, the cost of a plan may be approximated by the sum of communication cost, source query processing costs and mediator processing cost, as expressed in formula 4. _ _ _ (4) Furthermore  ... 
doi:10.5772/15823 fatcat:735xevz3z5gspbgpvl6u5ofdti

Querying Real World Services Through the Semantic Web [chapter]

Kaoru Hiramatsu, Jun-ichi Akahani, Tetsuji Satoh
2004 Lecture Notes in Computer Science  
The meta data and the ontologies enable systems to infer related classes while modifying the queries and retrieving approximate result and help them smooth obstacles in interaction while querying.  ...  The standardized technologies help us to describe the meta data and the ontologies in RDF (Resource Description Framework) and OWL (Web Ontology Language) formally and enable us to share them on the network  ...  Thanks are due to content holders for the permission to use their Web pages concerned with Kyoto, and to Yuji Nagato and Yoshikazu Furukawa of NTT Comware Corporation for their great contributions to demonstrating  ... 
doi:10.1007/978-3-540-30475-3_51 fatcat:ua3fy25e6beblazkme67cyoywq
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