The ontology contains OWL axioms specifying comprehensive information about the underlying concepts in the dataset. The original ontology was developed at the University of Oslo (Project Link), and it models information concerning the petroleum activities on the Norwegian continental shelf like operating companies and production licences, fields and discoveries, facilities and pipelines, to wellbores and stratigraphic data shelf.
The ontology used in the benchmark is a maximal OWL2 QL subset of the original NPD ontology. The following table shows relevant statistics about the structure of the ontology.
| #classes | #obj_prop | #data_prop | #intensional_axioms | max_depth | avg_siblings |
|---|---|---|---|---|---|
| 343 | 142 | 238 | 1451 | 10 | 4.83 |
Skjæveland, Martin G & Lian, Espen Hallenstvedt (2013). Benefits of Publishing the Norwegian Petroleum Directorate’s FactPages as Linked Open Data , In Erlend Tøssebro & Hein Meling (ed.), Norsk informatikkonferanse NIK 2013, Universitetet i Stavanger, 18. - 20.november 2013. Akademika forlag. ISBN 978-82-321-0365-2. Chapter 6. s 52 - 63
Skjæveland, Martin G; Lian, Espen Hallenstvedt & Horrocks, Ian (2013). Publishing the Norwegian Petroleum Directorate’s FactPages as Semantic Web Data , In Harith Alani; Lalana Kagal; Achille Fokoue; Paul Groth; Christian Biemann; Josiane Parreira; Lora Aroyo; Natasha Noy; Chris Welty & Krzysztof Janowicz (ed.), The Semantic Web – ISWC 2013 12th International Semantic Web Conference, Sydney, NSW, Australia, October 21-25, 2013, Proceedings, Part II. Springer. ISBN 978-3-642-41337-7. chapter. s 162 - 177