Auflistung nach Schlagwort "Ontology-based data access"
1 - 3 von 3
Treffer pro Seite
Sortieroptionen
- ZeitschriftenartikelA Terminology Service Supporting Semantic Annotation, Integration, Discovery and Analysis of Interdisciplinary Research Data(Datenbank-Spektrum: Vol. 16, No. 3, 2016) Karam, Naouel; Müller-Birn, Claudia; Gleisberg, Maren; Fichtmüller, David; Tolksdorf, Robert; Güntsch, AntonResearch has become more data-intensive over the last few decades. Sharing research data is often a challenge, especially for interdisciplinary collaborative projects. One primary goal of a research infrastructure for data management should be to enable efficient data discovery and integration of heterogeneous data. In order to enable such interoperability, a lot of effort has been undertaken by scientists to develop standards and characterize their domain knowledge in the form of taxonomies and formal ontologies. However, these knowledge models are often disconnected and distributed. The work presented here provides a promising approach for integrating and harmonizing terminological resources to serve as a backbone for a platform. The component developed, called the GFBio Terminology Service, acts as a semantic platform for access, development and reasoning over internally and externally maintained terminological resources within the biological and environmental domain. We highlight the utility of the Terminology Service by practical use cases of semantically enhanced components. We show how the Terminology Service enables applications to add meaning to their data by giving access to the knowledge that can be derived from the terminologies and data annotated by them.
- ZeitschriftenartikelOntology-Mediated Querying with Horn Description Logics(KI - Künstliche Intelligenz: Vol. 34, No. 4, 2020) Sabellek, LeifAn ontology-mediated query (OMQ) consists of a database query paired with an ontology. When evaluated on a database, an OMQ returns not only the answers that are already in the database, but also those answers that can be obtained via logical reasoning using rules from ontology. There are many open questions regarding the complexities of problems related to OMQs. Motivated by the use of ontologies in practice, new reasoning problems which have never been considered in the context of ontologies become relevant, since they can improve the usability of ontology enriched systems. This thesis deals with various reasoning problems that emerge from ontology-mediated querying and it investigates the computational complexity of these problems. We focus on ontologies formulated in Horn description logics, which are a popular choice for ontologies in practice. In particular, the thesis gives results regarding the data complexity of OMQ evaluation by completely classifying complexity and rewritability questions for OMQs based on an EL ontology and a conjunctive query. Furthermore, the query-by-example problem, and the expressibility and verification problem in ontology-based data access are introduced and investigated.
- ZeitschriftenartikelSemantic Technologies for Situation Awareness(KI - Künstliche Intelligenz: Vol. 34, No. 4, 2020) Baader, Franz; Borgwardt, Stefan; Koopmann, Patrick; Thost, Veronika; Turhan, Anni-YasminThe project “Semantic Technologies for Situation Awareness” was concerned with detecting certain critical situations from data obtained by observing a complex hard- and software system, in order to trigger actions that allow this system to save energy. The general idea was to formalize situations as ontology-mediated queries, but in order to express the relevant situations, both the employed ontology language and the query language had to be extended. In this paper we sketch the general approach and then concentrate on reporting the formal results obtained for reasoning in these extensions, but do not describe the application that triggered these extensions in detail.