RDF Vocabulary

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An RDF Vocabulary is an RDF graph that is a controlled vocabulary.



References

2010

  • http://msdn.microsoft.com/en-us/library/aa303663.aspx
    • A Resource Description Foundation (RDF) vocabulary is a defined set of predicates that can be used in an application. You can define a vocabulary for your application by creating an ontology file, which is an RDF document that contains all possible predicates for an application. An ontology not only defines the predicates themselves, but defines the data type of each predicate and the relationship, if any, of one predicate to another.

      A vocabulary is similar to a schema in that it defines a set of elements that can be used in an application. However, a vocabulary also helps you to define the domain and range of a predicate. You can define a domain to indicate that the predicate is of a particular RDF class. You can define a range to indicate that the predicate is of a particular data type. For example, if you have defined a predicate in an ontology file named UserInfo, you can create an e-mail-address predicate that is of type UserInfo in your ontology document. You could also define the data type, or range, of the E-mail-Address predicate.

      [[RDF Vocabulary|RDF vocabularies can describe relationships between vocabulary items from multiple vocabularies that have been developed independently. Because URI-References are used to identify classes and properties in the Web, it is possible to create new predicates that have a domain or range the value of which is a class that has been defined in another namespace.

      The following sample from an RDF ontology document defines an E-mail-Address predicate that is available to your application. This definition uses the RDFS domain and range elements to create relationships between the predicate and parent classes that are found in the vocabulary.

<rdf:Description rdf:about="#E-mail-Address">
   <rdf:type>
       <rdf:Description rdf:about="http://www.w3.org/2002/07/owl#DatatypeProperty"/>
   </rdf:type>
   <rdfs:domain>
       <rdf:Description rdf:about="#UserInfo"/>
   </rdfs:domain>
   <rdfs:domain>
       <rdf:Description rdf:about="#Organizational-Person"/>
   </rdfs:domain>
   <rdfs:range>
       <rdf:Description rdf:about="http://www.w3.org/2001/XMLSchema#string"/>
   </rdfs:range>
</rdf:Description>
    • You should develop a good RDF ontology and use it as a guide when you build applications that compose messages to send to the Profile Manager Web service.

2006

  • http://www.w3.org/2006/07/SWD/wiki/VocabMgtDraft.html
    • An RDF vocabulary is a set of resources denoted by URIs. Informally, these resources are known as the "terms" of the vocabulary. The resources will usually (but not necessarily) be of type rdf:Property, rdfs:Class, owl:Class, or skos:Concept.

      An RDF vocabulary is created and maintained for the use of a community of people (the 'user community') as a set of building blocks for creating RDF descriptions of things in their domain of interest. An RDF vocabulary usually implies a shared conceptualisation, and thus the notion of an 'RDF vocabulary' is almost identical to the notion of a 'web ontology' [ref???]. (efk: consider taking this last sentence out ...)

      Many controlled vocabularies have been encoded in RDF, OWL, and other knowledge representation languages, and a growing number of these are available in the public domain. A fraction of these appear to have fostered significant reuse to date, however [ref. recent discussion thread on mapping the Semantic Web]. While there are many issues that can limit reuse opportunities, a significant contributor is the lack of well-specified policies for vocabulary management, metadata, and provenance specification, depending on the application. Several of the most prominent RDF vocabularies currently in use (e.g., OWL, FOAF, Dublin Core, SKOS Core) have emerged from a close collaboration between a relatively small community of developers and a larger community of users. The prominence of these vocabularies may be attributed to their utility, but also to the commitment made by those responsible for developing/maintaining the vocabularies to forming, accomodating, serving, and working with, a community of users.

2001

  • http://www.w3.org/2001/sw/BestPractices/VM/principles/20050705
    • An RDF vocabulary is a set of resources denoted by URIs. Informally, these resources are known as the "terms" of the vocabulary. The resources will usually (but not necessarily) be of type rdf:Property, rdfs:Class, owl:Class, or skos:Concept.

      An RDF vocabulary is created and maintained for the use of a community of people (the 'user community') as a set of building blocks for creating RDF descriptions of things in their domain of interest. An RDF vocabulary usually implies a shared conceptualisation, and thus the notion of an 'RDF vocabulary' is almost identical to the notion of a 'web ontology' [ref???].