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VOLT: A Provenance-Producing, Transparent SPARQL Proxy for the On-Demand Computation of Linked Data and its Application to Spatiotemporally Dependent Data [chapter]

Blake Regalia, Krzysztof Janowicz, Song Gao
2016 Lecture Notes in Computer Science  
of query results and their derived (scientific) findings, and the lack of computational capabilities required for many tasks.  ...  In this work, we introduce a proxy that can transparently run on top of arbitrary SPARQL endpoints to enable the on-demand computation of Linked Data together with the provenance information required to  ...  The authors would also like to thank Johannes Gross from NASA/JPL for his comments.  ... 
doi:10.1007/978-3-319-34129-3_32 fatcat:hmsjtxrfgjcj3byrlw7dctmwti

Ontology-Based Data Access Using Rewriting, OWL 2 RL Systems and Repairing [chapter]

Giorgos Stoilos
2014 Lecture Notes in Computer Science  
Second, we show how (arbitrary) conjunctive queries can be supported by integrating well-known query rewriting techniques with OWL 2 RL systems via repairing.  ...  ans that is generally incomplete for O becomes complete for all SPARQL queries when used with O ∪ R.  ...  We would also like to thank Yujiao Zhou for providing fly anatomy and its queries.  ... 
doi:10.1007/978-3-319-07443-6_22 fatcat:e6f57dduonabbgxtdthadmiggq

RDFProv: A relational RDF store for querying and managing scientific workflow provenance

Artem Chebotko, Shiyong Lu, Xubo Fei, Farshad Fotouhi
2010 Data & Knowledge Engineering  
ontology to relational DB schema RDF triples to relational tuples SPARQL queries to SQL queries OWL RDF SPARQL Inference RDBMS SQL  ...  In this paper, we elaborate on the design of a relational RDF store, called RDFProv, that is optimized for scientific workflow provenance querying and management.  ...  Hartig and Heese [59] propose a SPARQL query graph model and pursue query rewriting based on this model.  ... 
doi:10.1016/j.datak.2010.03.005 fatcat:hbwenralmjeephtly2bmcnx7qe

Optimizing Analytical Queries over Semantic Web Sources [article]

Dilshod Ibragimov
2017 PhD series, Technical Faculty of IT and Design, ˜Aalborg=ålborgœ University  
FederaTion of SPARQL Endpoints) -a system for computing aggregate SPARQL queries over a federation of SPARQL endpoints.  ...  We obtain a local query P L , endpoint queries P e 1 , . . . , P e n , and the P AGG that describes how to compute the aggregation and how to connect the other subqueries.  ... 
doi:10.5278/vbn.phd.tech.00022 fatcat:5d2lmnicazgmze2qhe5cikowwm

Searching Linked Data and Services with a Single Query [chapter]

Mohamed Lamine Mouhoub
2014 Lecture Notes in Computer Science  
Furthermore, we aim to introduce an approach that integrates data queries with data from service calls and compositions.  ...  Moreover, machine-understandability of semantics allows for efficient search and integration of data.  ...  If yes, then how to define this syntax [2] and how to rewrite these no-standard queries to send them to SPARQL endpoints in the LOD. -How to address the heterogeneity of SWS descriptions?  ... 
doi:10.1007/978-3-319-07443-6_59 fatcat:mtlfqwpyxbck7csxjbbtmnjkre

Rules and Ontology Based Data Access [chapter]

Guohui Xiao, Martin Rezk, Mariano Rodríguez-Muro, Diego Calvanese
2014 Lecture Notes in Computer Science  
In OBDA an ontology defines a high level global vocabulary for user queries, and such vocabulary is mapped to (typically relational) databases.  ...  We consider evaluation of SPARQL queries under rules with linear recursion, which in principle is carried out by a 2-phase translation to SQL: (1) The SPARQL query, together with the RIF/SWRL rules, and  ...  We thank Héctor Pérez-Urbina for his support in evaluating Stardog.  ... 
doi:10.1007/978-3-319-11113-1_11 fatcat:uqm6evalvjfy3ffrn4qpfxem54

Relational Databases as Semantic Web Endpoints [chapter]

Matthias Hert
2009 Lecture Notes in Computer Science  
We introduce our approach for translating SPARQL/Update operations to SQL, describe how scalable reasoning can be realized by using the power of the database system, and outline two case studies for evaluating  ...  It presents the benefits of ontology-based read and write access to existing relational data as well as the need for specialized, scalable reasoning over that data.  ...  RDQuery [4] enables SPARQL-based access to relational data by translating the queries to SQL via mappings expressed in Relational.OWL.  ... 
doi:10.1007/978-3-642-02121-3_84 fatcat:mncx3ldjvfc5nbtajfrbe6migi

Recursion in SPARQL [chapter]

Juan L. Reutter, Adrián Soto, Domagoj Vrgoč
2015 Lecture Notes in Computer Science  
In this paper we propose a general purpose recursion operator to be added to SPARQL, formalize its syntax and develop algorithms for evaluating it in practical scenarios.  ...  We also show how to implement recursion as a plug-in on top of existing systems and test its performance on several real world datasets.  ...  This work was funded by the Millennium Nucleus Center for Semantic Web Research Grant NC120004. We would like to thank Aidan Hogan, Egor Kostylev, James Cheney and the reviewers for helpful comments.  ... 
doi:10.1007/978-3-319-25007-6_2 fatcat:a464skqzm5bndcnfhqorpbqtpe

Automatic Query-Centric API for Routine Access to Linked Data [chapter]

Albert Meroño-Peñuela, Rinke Hoekstra
2017 Lecture Notes in Computer Science  
As a result, applications and data cannot be cleanly separated: SPARQL queries, endpoint addresses, namespaces, and URIs end up as part of the application code.  ...  The resulting APIs require no coding, rely on low-cost external query storage and versioning services, contain abundant provenance information, and integrate access to different publishing paradigms into  ...  We also want to thank Laurens Rietveld for his technical suggestions, and Richard Zijdeman and Auke Rijpma for their testing.  ... 
doi:10.1007/978-3-319-68204-4_30 fatcat:eij2z54eczfprlmjlyguk3k3p4

Automatically exposing OpenLifeData via SADI semantic Web Services

Alejandro González, Alison Callahan, José Cruz-Toledo, Adrian Garcia, Mikel Egaña Aranguren, Michel Dumontier, Mark D Wilkinson
2014 Journal of Biomedical Semantics  
We also demonstrate that, via clients such as SHARE, the complexity of federated SPARQL queries is dramatically reduced.  ...  well as providing a standardized mechanism for data access.  ...  the computational load required for exploratory queries and enable new applications.  ... 
doi:10.1186/2041-1480-5-46 pmid:25937881 pmcid:PMC4417525 fatcat:gsz6pcu3efebxe654oygqfl6ym

Linked Data-as-a-Service: The Semantic Web Redeployed [chapter]

Laurens Rietveld, Ruben Verborgh, Wouter Beek, Miel Vander Sande, Stefan Schlobach
2015 Lecture Notes in Computer Science  
In other words, hosting data online is easy, but publishing Linked Data via a queryable API such as SPARQL appears to be too difficult.  ...  As a consequence, in practice, there is no single uniform way to query the LOD Cloud today.  ...  Even though there is a client-side rewriter that allows SPARQL queries to be performed against an LDF server backend, the standards-compliance of this rewriter is not assessed in this paper. 13 See http  ... 
doi:10.1007/978-3-319-18818-8_29 fatcat:yr7fzkfp5fbrhjckvn5wfzc65q

SPARQL Query Re-writing Using Partonomy Based Transformation Rules [chapter]

Prateek Jain, Peter Z. Yeh, Kunal Verma, Cory A. Henson, Amit P. Sheth
2009 Lecture Notes in Computer Science  
For querying ontology's containing spatial information, the precise relationships between spatial entities has to be specified in the basic graph pattern of SPARQL query which can result in long and complex  ...  We present a novel approach to help users intuitively write SPARQL queries to query spatial data, rather than relying on knowledge of the ontology structure.  ...  This research is funded primarily by NSF Award#IIS-0842129, titled "III-SGER: Spatio-Temporal-Thematic Queries of Semantic Web Data: a Study of Expressivity and Efficiency" and secondarily by NSF ITR Award  ... 
doi:10.1007/978-3-642-10436-7_9 fatcat:r7kh4xy7vbda5jkpx2azxu6zby

grlc Makes GitHub Taste Like Linked Data APIs [chapter]

Albert Meroño-Peñuela, Rinke Hoekstra
2016 Lecture Notes in Computer Science  
Recent work speeds up this Linked Data API construction by wrapping it around SPARQL queries, which carry out the API functionality under the hood.  ...  Inspired by this, in this paper we present grlc, a lightweight server that translates SPARQL queries curated in GitHub repositories to Linked Data APIs on the fly.  ...  However, the question of how to effectively store and organise such API-translated SPARQL queries remains.  ... 
doi:10.1007/978-3-319-47602-5_48 fatcat:ogruqzg5rjcnfnvetzk6c3tuc4

A Framework for Searching Semantic Data and Services with SPARQL [chapter]

Mohamed Lamine Mouhoub, Daniela Grigori, Maude Manouvrier
2014 Lecture Notes in Computer Science  
In this paper, we introduce a SPARQL-driven approach for searching linked data and relevant services. In our framework, a user data query is analyzed and transformed into service requests.  ...  Our system also features automatic web service composition to help finding more answers for user queries.  ...  This later one can be queried directly via a local SPARQL endpoint.  ... 
doi:10.1007/978-3-662-45391-9_9 fatcat:4uekf4t54ndb3gdbwsjj77hhua

Ontology-based data access – Beyond relational sources

Elena Botoeva, Diego Calvanese, Benjamin Cogrel, Julien Corman, Guohui Xiao, Andrea Passerini, Chiara Ghidini, Bernardo Magnini
2019 Intelligenza Artificiale  
To enable access to such data, we generalize the well-known ontology-based data access (OBDA) framework so as to allow for querying arbitrary data sources using sparql.  ...  We propose an architecture for a generalized OBDA system implementing the virtual approach.  ...  ., computing the answer to the original sparql query q over the OBDA instance according to the owl 2 ql entailment regime can be reduced to evaluating q 1 over the relational view.  ... 
doi:10.3233/ia-190023 fatcat:yvfgbymmtjgsdo7pty22pkumx4
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