tombaker
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1 year ago The DCMI Metadata Terms specification says: explanation:
DCMI metadata terms are expressed in RDF vocabularies for use in Linked Data. Creators of non-RDF metadata can use the terms in contexts such as XML, JSON, UML, or relational databases by disregarding both the global identifier and the formal implications of the RDF-specific aspects of term definitions. Such users can take domain, range, subproperty, and subclass relations as usage suggestions and focus on the natural-language text of definitions, usage notes, and examples.
The Introduction to ISO 15836 Part 2 says:
This set of properties and classes is expressed as an RDF vocabulary and may be used in Linked Data. Each property and class has a global identifier (URI).
The ISO 15836 glossary defines terminology used in the standard in that way that makes explicit their basis in RDF. "Class" is defined as follows:
The members of a class are known as instances of the class. Classes are themselves resources. They are often identified by URIs and may be described using RDF properties. The rdf:type property may be used to state that a resource is an instance of a class. [SOURCE: RDF Schema 1.1]
And "property" is defined as:
relation between subject resources and object resources
Note 1 to entry: This is a synonym of “element”. [SOURCE: RDF Schema 1.1]
And "subproperty":
property that is related, typically using the rdfs:subPropertyOf property, to another property typically of broader scope (superproperty), such that all resources related by the subproperty are also related by the superproperty [Source: RDF Schema 1.1]
In addition, each property and class in the ISO standard has a URI, and any domains, ranges are specified with URIs.
In addition, ISO 15836 Part 2 has an Annex B (informative), "Dublin Core metadata as linked data", which explains:
Dublin Core metadata may contain three kinds of links:
URIs of the described resources themselves (such as works and their manifestations)
URIs of the schema elements
URIs of the values (such as names, subject headings)
Resource URIs may be based on standard identifiers such as International Standard Book Number (ISBN) for books or International Standard Text Code (ISTC) for textual works. They may be used for providing persistent links to the resources or metadata about them. Identifiers are also an efficient means for linking for instance work and manifestation metadata records of the same resource, or for linking interrelated works or manifestations.
Schema element URIs may be used to link the data element (term) into its description, in order to foster machine (and human) readability of the metadata.
Value URIs may be used for creating links from element values (such as Albert Einstein as an author) to relevant Internet resources. URIs are either Uniform Resource Locators (URLs) or persistent identifiers such as Uniform Resource Names (URNs). Persistent identifiers may be linked to 1-n Web resources via a PID resolution process.
Dublin Core standard specifies only the links of the 2nd type. Linking to either resources themselves or term values is beyond the scope of this standard.
For over twenty years DCMI has sought to balance the need to clearly state that DCMI metadata terms are based on RDF with a need to point out that the standard is also, in some sense, technology neutral.
In the 2000s, it was controversial within DCMI to commit too strongly to RDF. The DCMI Abstract Model was developed between 2003 and 2007 as an RDF-compatible replacement for a metadata model that had emerged from DC workshops and conferences between 1996 and 2001 and that was unique to DCMI.
The Abstract Model never found wide adoption, perhaps because it was seen as too formal and RDF-like for people who were used to seeing metadata as ad-hoc document structures (eg, MARC, XML) while not being recognized by the Semantic Web community as something clearly based on RDF. Instead of bridging a gap, it fell between two stools.
Might we formulate a public position on this question to be featured prominently on the website?