Uses common entailment regimes and understands their uses. – Linked Data for Professional Education

RDF Homework Exercises

Sat, 21 Jan 2017 06:46:41 +0000

This document contains several "written" and "electronic" homework questions originally from the course "Semantic Web Topics" at LeHigh University. They include: Translating an RDF Graph into the Turtle syntax; Using the RDFS entailment rules determine what triples can be inferred from an RDF Graph; Explain the advantage of using multiple rdfs:range statements over using the union of the individual ranges to determine the actual range; Draw the equivalent graph when given an RDF document written in XML; Write the equivalent RDF/XML for a series of online references; Using Jena, write a class object that can read in an RDF file that was written using a specific vocabulary and output a list of the publications, one per line.

URL: http://www.cse.lehigh.edu/~heflin/courses/sw-2013/hw1.pdf
Keywords: Turtle, RDF Schema, Entailment regimes, eXtensible Markup Language (XML), Apache Jena, Java
Author: Heflin, Jeff
Date created: 2013-02-01 05:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P4H
Educational use: assessment
Educational audience: teacher-educationSpecialist
Interactivity type: active

SPARQL and Linked Data Homework Exercises

Sat, 21 Jan 2017 06:46:40 +0000

This document contains several "written" and "electronic" homework questions originally from the course "Semantic Web Topics" at LeHigh University. They include: Write a series of SPARQL queries using a provided schema; Write a SPARQL construct query that generates all triples inferred by a specific RDFS entailment rule; Write a SPARQL construct query to generate
owl:sameAs statements between domains which share specified property; Describe the pros and cons of generating links in the manner specified in the previous question; Using Jena, create a class that can read in all the files in a specified directory and create a Web page that lists a series of publications organized by topic – reading all of the files into a single model and only using SPARQL to retrieve information from the model.

URL: http://www.cse.lehigh.edu/~heflin/courses/sw-2013/hw2.pdf
Keywords: SPARQL, RDF Schema, Entailment regime, Apache Jena, Java
Author: Heflin, Jeff
Date created: 2013-02-01 05:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P4H
Educational use: assessment
Educational audience: teacher-educationSpecialist
Interactivity type: active

Querying Linked Data

Fri, 21 Oct 2016 05:39:20 +0000

This module looks in great detail at SPARQL and introduces approaches for querying and updating semantic data. It covers the SPARQL algebra, the SPARQL 1.1 protocol, and provides examples for reasoning over Linked Data. The module uses examples from the music domain, which can be directly tried out and ran over the MusicBrainz dataset. This includes gaining familiarity with the RDFS and OWL languages, which allow developers to formulate generic and conceptual knowledge that can be exploited by automatic reasoning services in order to enhance the power of querying.

URL: http://www.euclid-project.eu/modules/chapter2.html
Keywords: Inferencing, SPARQL, RDF Schema, Web Ontology Language (OWL), Semantic Web, Entailment
Author: Norton, Barry
Publisher: EUCLID Project
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P3H
Educational use: professionalDevelopment
Educational audience: professional
Interactivity type: expositive

On the Semantics of SPARQL Queries with Optional Matching under Entailment Regimes

Sat, 16 Jan 2016 13:43:29 +0000

This presentation covers the semantics of SPARQL queries with optional matching features under entailment regimes. It argues that normative semantics may lead to answers that are in conflict with the intuitive meaning of optional matching, where unbound variables naturally represent unknown information. The presenters propose an extension of the SPARQL algebra that addresses these issues and is compatible with any entailment regime satisfying the minimal requirements given in the normative specification. They argue that this solution comes at no cost for regimes with an entailment relation of reasonable complexity and that it preserves the known properties of optional matching that are commonly exploited for static analysis and optimization.

URL: http://videolectures.net/iswc2014_kostylev_sparql_queries/
Keywords: Entailment regimes, Unbound variable, Normative semantics, Web Ontology Language (OWL), Strict semantics
Author: Kostylev, Egor
Date created: 2014-12-19 05:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P15M

Answering SPARQL Queries over Databases under OWL 2 QL Entailment Regime

Sat, 16 Jan 2016 13:43:29 +0000

This video presents an extension of the ontology-based data access platform Ontop that supports answering SPARQL queries under the OWL 2 QL direct semantics entailment regime for data instances stored in relational databases. On the theoretical side, we show how any input SPARQL query, OWL 2 QL ontology and R2RML mappings can be rewritten to an equivalent SQL query solely over the data. On the practical side, we present initial experimental results demonstrating that by applying Ontop technologies the system produces scalable SQL queries.

URL: http://videolectures.net/iswc2014_kontchakov_sparql_queries/
Keywords: Ontop, Entailment Regimes, Ontology-Based Data Access (ODBA), Query rewriting, RDBMS, Relational model
Author: Kontchakov, Roman
Date created: 2014-12-19 05:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P20M

RDF, SPARQL and Semantic Repositories

Abi Evans — Fri, 09 Oct 2015 12:05:16 +0000

This massive slide presentation covers a LOT of ground, including. It begins with the benefits of using RDF, RDFS/OWL entailment rules and how they can be used for inferencing, and a thorough discussion of the OWL language and its flavors. The next section covers the SPARQL query language , discussing its basic features and how it compares to SQL. Moving on, the next few sections cover semantic repositories as well as bench-marking and scalability. Then, the use of MapReduce for massively distributed RDF materialization is discussed, followed by RDBMS-to-RDF mapping approaches and tools. Finally, various RDF tools (including ontology editors, RDF-izers, and RDF APIs) are presented.

URL: http://www.slideshare.net/marin_dimitrov/rdf-sparql-and-semantic-repositories
Keywords: SPARQL, Web Ontology Language (OWL), RDF Schema, Semantic repositories, MapReduce, RDB2RDF
Author: Dimitrov, Marin
Publisher: Ontotext
Date created: 2010-09-15 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P90M
Educational use: instruction
Educational audience: student

Answering Queries Over OWL Ontologies with SPARQL

Abi Evans — Tue, 15 Sep 2015 02:33:09 +0000

This slide presentation discusses the various types of RDF Schema and OWL entailment regimes defined by SPARQL 1.1. It highlights where limitations and restrictions exist and suggests ways to make SPARQL-to-OWL queries more efficient. Options include class-property hierarchy exploitation, as well as exploiting domain and range restrictions. Very complex stuff- a version with audio would be most helpful.

URL: http://webont.org/owled/2011/presentations/4Kollia.pdf
Keywords: Web Ontology Language (OWL), OWL Reasoner, Basic Graph Pattern (BGP), Direct Semantics (DS)
Author: Grove, Mike
Date created: 2011-06-06 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P30M
Educational use: instruction
Educational audience: student
Interactivity type: expositive

IRIS RDFS Reasoner

Abi Evans — Tue, 15 Sep 2015 02:33:09 +0000

The RDFS Reasoner is a framework that enables reasoning over RDF Schema ontologies and that uses IRIS as underlying reasoning engine. The RDFS Reasoner implementation is based on the work described in the paper "RDF and Logic: Reasoning and Extension". The RDFS Reasoner translates ontology descriptions in RDF Schema to F-Logic molecules and rules. The RDFS Reasoner currently supports the simple, RDF, RDF Schema and extensional RDFS (eRDFS) entailment regimes and allows WSML conjunctive queries as queries. Page contains links to an online demo and a downloadable package.

URL: http://www.iris-reasoner.org/rdfsreasoner
Keywords: Web Service Modeling Language (WSML), Description Logics, F-Logic, Ontology, RDF Schema
Author: Bishop, Barry
Publisher: IRIS
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P60M
Educational audience: professional
Interactivity type: active

RDF and Logic: Reasoning and Extension

Abi Evans — Tue, 15 Sep 2015 02:33:09 +0000

This paper explores embedding the various kinds of RDF entailment in F-Logic. It shows that the embedding of simple, RDF, and RDFS entailment, as well as a large fragment of extensional RDFS entailment, fall in the Datalog fragment of F-Logic, allowing the use of optimization techniques from the area of deductive databases for reasoning with RDF. Using earlier results on the relationship between F-Logic and Description Logics (DLs), we define an embedding of a large fragment of extensional RDFS in a tractable description logic, namely DL-Lite, allowing efficient reasoning over the ontology vocabulary. We show how, using these embeddings, RDFS can be extended with rules and/or general axioms.

URL: http://stijnheymans.net/pubs/webs2007.pdf
Keywords: RDF Schema, Entailment Regimes, Datalog, Description Logics, F-Logic
Author: Heymans, Stijn
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P30M
Educational use: instruction
Educational audience: teacher-educationSpecialist
Interactivity type: expositive

Expressive Languages for Querying the Semantic Web

Abi Evans — Tue, 15 Sep 2015 02:33:09 +0000

SPARQL 1.1 was recently released, which includes entailment regimes for
RDFS and OWL vocabularies and a mechanism to express navigation patterns through regular expressions. Unfortunately, there are still some useful navigation patterns that cannot be expressed in SPARQL 1.1, and the language lacks of a general mechanism to express recursive queries. To the best of the authors' knowledge, there is no RDF query language that combines the above functionalities, and which can also be evaluated efficiently. It is the aim of this work to fill this gap.

URL: http://ciws.cl/media/pdf/pods14.pdf
Keywords: RDF Schema, SPARQL, Web Ontology Language (OWL), Entailment regimes, Datalog
Author: Pieris, Andreas
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P30M
Educational use: instruction
Educational audience: teacher-educationSpecialist
Interactivity type: expositive