1.
Metadata for web
ontologies and rules:
current practices and
perspectives
Carlos Tejo-Alonso, Diego
Berrueta, Luis Polo and Sergio
Fernández

2.
Context
<rdf:Description rdf:about="#Bicycle ">
<rdf:type rdf:resource="&owl;Class"/> logic
<rdfs:subClassOf rdf:resource="#Vehicle"/>
<rdfs:label xml:lang="en">bicycle</rdfs:label>
<dct:description xml:lang="en">
Vehicle consisting of two wheels held in a
frame one behind other, propelled by pedals
</dct:description> annotation
<dc:creator>Iván Mínguez</dc:creator>
</rdf:Description>

3.
Motivation to annotate
• Facilitate search
• Improve exchange and reuse
• Link them to the natural language
• Generate reference documentation

4.
Overview
• Current ontology & rule metadata usage
• Proposed vocabulary to annotate rules
• Parrot, a documentation tool for
ontologies and rules
• Conclusions/Future Work

5.
Metadata vocabularies
• General purpose: DC, SKOS or RDFS
– dc:creator, skos:prefLabel, rdfs:comment
• For ontologies: OWL
– owl:versionInfo
• For rules: no specific vocabulary
(with significant adoption)

6.
Ontology metadata study

7.
Ontology metadata study
• Massive use of RDF Schema(label & comment)
• Property synonymy
dc:description rdfs:comment
dct:description skos:definition
• Absence of:
– multimedia
– legal rights and license information
– expressive multilingual metadata

8.
Rule metadata: a proposal
Metadata Recommended properties
Labeling dc:title, dct:title, rdfs:label,
skos:prefLabel, skos:altLabel
Authoring foaf:maker, dc:creator, dc:contributor,
dc:publisher, dct:creator, dct:contributor,
dct:publisher
Description dc:description, dct:description, rdfs:comment,
skos:definition, skos:example, skos:note
Multimedia foaf:depiction, og:video
Versioning owl:versionInfo, dct:hasVersion,
skos:changeNote
Rights dc:rights, dct:license
Date dc:date, dct:issued, dct:modified
Documentation dct:source, rdfs:seeAlso, rdfs:isDefinedBy

9.
Annotated rule (example)
(* ex:rule ex:rule [
rdfs:label -> “Example Rule”@en
dc:creator -> “Luis Polo” annotatio
dc:date -> “1981-01-20”
og:video ->
n
<http://youtu.be/5h10QHpA5EU>
dct:publisher -> http://ontorule-project.eu
] *)
Forall ?person ?age (
If And( ?person #foaf :Person logic
?person [foaf:age -> ?age]
External(pred:numeric-less-than(?age 18))
)
Then Do( Assert(?person#ex:Under18Person) )

10.
Parrot overview
OWL
Report
RIF
• Multimedia-rich, customizable reports for humans
• Supports multiple metadata
• Combination of rules and ontologies
• Supports multilingual annotations

11.
Parrot usage
Web service
Eclipse plugin
Command Line Interface

12.
Parrot DEMO
http://ontorule-project.eu/parrot

13.
Conclusions
• Ontology metadata exists in the wild, but
there is still room for improvement
• Metadata facilitate rule exchange between
Business Rules Management System
• We expect to impact on the quality and
quantity of the metadata annotations in rules
and ontologies

14.
Future work
• To expand the analysis to large ontologies
• To account the use of metadata in RIF
documents as they become available
• To extend proposal of rule metadata
properties as new requirements arise

15.
Thanks for your attention
contact: carlos.tejo@fundacionctic.org
http://www.flickr.com/photos/ockam/2591316903/

16.
About this presentation
Fifth Metadata and
Semantics Research
Conference (MTSR 2011)
12-14 October 2011
Yaşar University, Izmir – TURKEY
http://mtsr2011.yasar.edu.tr

17.
Acknowledgements
This work has been partially supported by the
European Commission under ONTORULE project