Ontologies and the Semantic Web
This site introduces ontologies and the Semantic Web, with an emphasis on how ontologies are defined and used for applications. There are about about thirty [...]
Answering Queries Over OWL Ontologies with SPARQL
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 [...]
Querying Linked Data
This presentation looks in detail at SPARQL and introduces approaches for querying and updating semantic data. It covers the SPARQL algebra, the SPARQL protocol, and [...]
Introduction to Linked Data: Background Technologies and Standards, Motivating Application Scenario
This presentation introduces the main principles of Linked Data, including the underlying technologies and background standards. It provides basic knowledge for how data can be [...]
Schema-Agnostic Query Rewriting in SPARQL 1.1
SPARQL 1.1 supports the use of ontologies to enrich query results with logical entailments, and OWL 2 provides a dedicated fragment OWL QL for this [...]
Dynamic Querying of Mass-Storage RDF Data with Rule-Based Entailment Regimes?
SPARQL is the W3C standard for querying RDF data, but it mostly provides means for querying simple RDF graphs only, whereas querying with respect to [...]
Foundations of Semantic Web Technologies: SPARQL Entailment Regimes
Slides covering the following topics: SPARQL can now be used with RDF Schema, OWL, and RIF semantics. Entailment Regimes overwrite evaluation of basic graph patterns. [...]
SPARQL 1.1 Entailment Regimes
There are different possible ways of defining a basic graph pattern matching extension for an entailment relation. This document specifies one such way for a [...]
Answering SPARQL Queries over Databases under OWL 2 QL Entailment Regime
This paper presents an extension of the ontology-based data access platform Ontop that supports answering SPARQL queries under the OWL 2 QL direct semantics entailment [...]
Querying Semantic Web Data with SPARQL (and SPARQL 1.1)
This lengthy slide presentation covers SPARQL 1.1. It begins with the fundamentals: graph patterns, operators, and algebraic representations. The second half dives deeply into complex [...]