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CORNER: A Completeness Reasoner for SPARQL Queries Over RDF Data Sources [chapter]

Fariz Darari, Radityo Eko Prasojo, Werner Nutt
2014 Lecture Notes in Computer Science  
If a query can only be answered completely by a combination of sources, CORNER rewrites the original query into one with SPARQL SERVICE calls, which assigns each query part to a suitable source, and executes  ...  With CORNER, we specifically address the data quality aspect of completeness. CORNER supports SPARQL BGP queries and can take RDFS ontologies into account in its analysis.  ...  This work has been partially supported by the project "MAGIC: Managing Completeness of Data" funded by the province of Bozen-Bolzano, and the European Master's Program in Computational Logic (EMCL).  ... 
doi:10.1007/978-3-319-11955-7_40 fatcat:7hpcaprbhzdutoqv32qpivahou

SPLODGE: Systematic Generation of SPARQL Benchmark Queries for Linked Open Data [chapter]

Olaf Görlitz, Matthias Thimm, Steffen Staab
2012 Lecture Notes in Computer Science  
In this paper, we present a classification methodology for federated SPARQL queries.  ...  We further develop a heuristic called SPLODGE for automatic generation of benchmark queries that is based on this methodology and takes into account the number of sources to be queried and several complexity  ...  Introduction The Linked Data cloud offers a huge amount of machine readable, structured data and its full potential can only be leveraged by querying over multiple data sources.  ... 
doi:10.1007/978-3-642-35176-1_8 fatcat:5rzblxeufffbbmzan6fmpguz6i

Getting the Most Out of Wikidata: Semantic Technology Usage in Wikipedia's Knowledge Graph [chapter]

Stanislav Malyshev, Markus Krötzsch, Larry González, Julius Gonsior, Adrian Bielefeldt
2018 Lecture Notes in Computer Science  
A live SPARQL endpoint, regular RDF dumps, and linked data APIs are now forming the backbone of many uses of Wikidata.  ...  A major challenge for bringing Wikidata to its full potential was to provide reliable and powerful services for data sharing and query, and the WMF has chosen to rely on semantic technologies for this  ...  The main reason for this choice was the availability of well-supported free and open source tools for the main tasks, especially for SPARQL query answering.  ... 
doi:10.1007/978-3-030-00668-6_23 fatcat:7w7wpb6ak5ai5mdnk4t25ps73a

Ontology Mapping and SPARQL Rewriting for Querying Federated RDF Data Sources [chapter]

Konstantinos Makris, Nektarios Gioldasis, Nikos Bikakis, Stavros Christodoulakis
2010 Lecture Notes in Computer Science  
In this paper we present a SPARQL query rewriting method which can be used to achieve interoperability in semantic information retrieval and/or knowledge discovery processes over interconnected RDF data  ...  Formal mappings between different overlapping ontologies are exploited in order to rewrite initial user SPARQL queries, so that they can be evaluated over different RDF data sources on different sites.  ...  The mappings are used to transform the original SPARQL query, through rewriting, to a set of SPARQL queries which are used to access the federated RDF data sources.  ... 
doi:10.1007/978-3-642-16949-6_32 fatcat:naklkyufxfd6zn4ed7or6tivj4

Semantic Data Extraction from Infobox Wikipedia Template

Amira AbdEl-atey, Sherif El-etriby, Arabi S. kishk
2012 International Journal of Computer Applications  
The output data is in RDF (Resource Description Framework) triple format which is the basic technology used for building the semantic web.  ...  The Wikipedia for example, succeeded in creating the by far largest encyclopedia just on the basis of a wiki. Wikis are created by wiki software and are often used to create collaborative works.  ...  We use SQL for querying database and SPARQL for querying RDF data. Semantic web provides a SPARQL endpoint for querying web data or knowledge base.  ... 
doi:10.5120/5072-7464 fatcat:oduwsuusune6fgvdi3xxwiqrdi

Facade-X: An Opinionated Approach to SPARQL Anything [chapter]

Enrico Daga, Luigi Asprino, Paul Mulholland, Aldo Gangemi
2021 Applications and Practices in Ontology Design, Extraction, and Reasoning  
RML), to know how to query and manipulate a variety of source formats (e.g. XPATH, JSON-Path), or to combine multiple languages (e.g. SPARQL Generate).  ...  In this paper, we explore an alternative solution and contribute a general-purpose meta-model for converting non-RDF resources into RDF: Facade-X.  ...  innovation programme through the project SPICE -Social Cohesion, Participation, and Inclusion through Cultural Engagement (Grant Agreement N. 870811),, and the project Polifonia: a  ... 
doi:10.3233/ssw210035 fatcat:yzr2lo2zjzadtjboappzqdh6wy

Databases under the Partial Closed-world Assumption: A Survey

Simon Razniewski, Werner Nutt
2014 Workshop Grundlagen von Datenbanken  
The IT department of the provincial school administration runs a database for storing school data, which is maintained in a de-  ...  INTRODUCTION Data completeness is an important aspect of data quality.  ...  This work has been partially supported by the project "MAGIC: Managing Completeness of Data" funded by the province of Bozen-Bolzano.  ... 
dblp:conf/gvd/RazniewskiN14 fatcat:5fn45yrqfnbkjos4ghzbxt725q

Enabling Semantic Queries Across Federated Bioinformatics Databases [article]

Ana Sima, Tarcisio Mendes de Farias, Erich Zbinden, Maria Anisimova, Manuel Gil, Heinz Stockinger, Kurt Stockinger, Marc Robinson-Rechavi, Christophe Dessimoz
2019 biorxiv/medrxiv   pre-print
To enable federated queries across these sources, we first defined a new semantic model for gene expression called GenEx.  ...  Similarly, the materialised RDF data of OMA, expressed in terms of the Orthology ontology, is made available in a public SPARQL endpoint.  ...  for OMA, Bgee, and Core-IT.  ... 
doi:10.1101/686600 fatcat:ajkv2fmvzvbxje3kychiolirxm

Facade-X: an opinionated approach to SPARQL anything

Enrico Daga, Luigi Asprino, Paul Mulholland, Aldo Gangemi
2021 Zenodo  
RML), to know how to query and manipulate a variety of source for- mats (e.g. XPATH, JSON-Path), or to combine multiple languages (e.g. SPARQL Generate).  ...  In this paper, we explore an alternative solution and contribute a general-purpose meta-model for converting non-RDF resources into RDF: Facade-X.  ...  The reason is that, in our naive implementation, the data source is completely transformed and loaded into a RDF dataset in-memory, before the query is evaluated.  ... 
doi:10.5281/zenodo.4927536 fatcat:jiovb4qdb5b4pldredy5klvvga

Enabling semantic queries across federated bioinformatics databases

2019 Database: The Journal of Biological Databases and Curation  
However, the heterogeneity of the different data sources, both at the syntactic and the semantic level, still poses significant challenges for achieving interoperability among biological databases.  ...  Data integration promises to be one of the main catalysts in enabling new insights to be drawn from the wealth of biological data available publicly.  ...  for OMA, Bgee, and Core-IT.  ... 
doi:10.1093/database/baz106 pmid:31697362 pmcid:PMC6836710 fatcat:o4fk52tkvrajfmf7qcdmgcygvu

GeoSPARQL Query Tool - A Geospatial Semantic Web Visual Query Tool

Ralph Grove, James Wilson, Dave Kolas, Nancy Wiegand
2014 Proceedings of the 10th International Conference on Web Information Systems and Technologies  
Protocols such as GeoSPARQL and stSPARQL extend SPARQL in order to take advantage of spatial relationships inherent in geospatial data.  ...  is being developed for the Semantic Geospatial Web.  ...  ACKNOWLEDGEMENTS Early versions of GeoQuery were based in part on a prototype query tool developed by USGS  ... 
doi:10.5220/0004797800330040 dblp:conf/webist/GroveWKW14 fatcat:7oyxhj43hrbqdgb7wvftqm2cea

Thesaurus-Based Search in Large Heterogeneous Collections [chapter]

Jan Wielemaker, Michiel Hildebrand, Jacco van Ossenbruggen, Guus Schreiber
2008 Lecture Notes in Computer Science  
We discuss details of scalable graph search, the required OWL reasoning functionalities and show why SPARQL queries are insufficient for solving the search problem. 5 The software can be found at http:  ...  The use of ClioPatria's search strategies is illustrated with a realistic use case: searching for "Picasso".  ...  Query API The SeRQL/SPARQL library provides a semantic web query interface that is compatible to Sesame [15] and provides open and standardised access to the RDF data stored in ClioPatria.  ... 
doi:10.1007/978-3-540-88564-1_44 fatcat:c53pnv7jlvah7nmavktoj7clr4

Semantic inference using chemogenomics data for drug discovery

Qian Zhu, Yuyin Sun, Sashikiran Challa, Ying Ding, Michael S Lajiness, David J Wild
2011 BMC Bioinformatics  
uses networks of ontologically annotated RDF statements along with deductive reasoning tools to infer new associations between the query structure and genes and diseases from WENDI results.  ...  Results Through the implementation of a semantic inference algorithm, rule set, Semantic Web methods (RDF, OWL and SPARQL) and new interfaces, we have created a new tool called Chemogenomic Explorer that  ...  We thank Bret Davidson for correcting English. We would like to thank the anonymous reviewers for their helpful comments and suggestions.  ... 
doi:10.1186/1471-2105-12-256 pmid:21699718 pmcid:PMC3225082 fatcat:udmnme6lzneytj3ruo5i7r46zy

No Size Fits All – Running the Star Schema Benchmark with SPARQL and RDF Aggregate Views [chapter]

Benedikt Kämpgen, Andreas Harth
2013 Lecture Notes in Computer Science  
A more direct approach than ROLAP is to load Statistical Linked Data into an RDF store and to answer OLAP queries using SPARQL.  ...  Statistics published as Linked Data promise efficient extraction, transformation and loading (ETL) into a database for decision support.  ...  We thank Günter Ladwig, Andreas Wagner and the anonymous reviewers for helpful support and feedback.  ... 
doi:10.1007/978-3-642-38288-8_20 fatcat:ta7ajhixxnfuzpbsl2xenva7k4

SAFE: SPARQL Federation over RDF Data Cubes with Access Control

Yasar Khan, Muhammad Saleem, Muntazir Mehdi, Aidan Hogan, Qaiser Mehmood, Dietrich Rebholz-Schuhmann, Ratnesh Sahay
2017 Journal of Biomedical Semantics  
Several query federation engines have been proposed for accessing public Linked Open Data sources.  ...  SAFE is designed specifically to query statistical RDF data cubes in a distributed setting, where access control is coupled with source selection, user profiles and their access rights.  ...  The source-code (AGPL License) of SAFE and queries and datasets used in the experiments can be found at  ... 
doi:10.1186/s13326-017-0112-6 pmid:28148277 pmcid:PMC5288952 fatcat:6uasf5avujhitpktgkkb7loryi
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