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Using ISO URNs

thammond

thammond – 2007 October 01

In Identifiers

(Update - 2007.10.02: Just realized that there were some serious flaws in the post below regarding publication and form of namespace URIs which I’ve now addressed in a subsequent post here.)

By way of experimenting with a use case for ISO URNs, below is a listing of the document metadata for an arbitrary PDF. (You can judge for yourselves whether the metadata disclosed here is sufficient to describe the document.) Here, the metadata is taken from the information dictionary and from the document metadata stream (XMP packet).

The metadata is expressed in RDF/N3. That may not be a surprise for the XMP packet which is serialized in RDF/XML, as it’s just a hop, skip and a jump to render it as RDF/N3 with properties taken from schema whose namespaces are identified by URI. What may be more unusual is to see the document information dictionary metadata (the “normal” metadata in a PDF) rendered as RDF/N3 since the information dictionary is not nodelled on RDF, not expressed in XML, and not namespaced. Here, in addition to the trusty HTTP URI scheme, I’ve made use of two particular URI schemes: “iso:” URN namespaces, and “data:” URIs.

(Continues.)

Whole Lotta ID

thammond

thammond – 2007 October 01

In Identifiers

ISO has registered with the IANA a URN namespace identifier (“iso:”) for ISO persistent resources. From the Internet-Draft: “This URN NID is intended for use for the identification of persistent resources published by the ISO standards body (including documents, document metadata, extracted resources such as standard schemata and standard value sets, and other resources).” The toplevel grammar rules (ABNF) give some indication of scope: NSS = std-nss std-nss = "

URI Template Republished

thammond

thammond – 2007 July 28

In Identifiers

Well, it all went very quiet for a while but glad to see that the URI Template Internet-Draft has just been republished: _“A New Internet-Draft is available from the on-line Internet-Drafts directories. Title : URI Template Author(s) : J. Gregorio, et al. Filename : draft-gregorio-uritemplate-01.txt Pages : 9 Date : 2007-7-23 URI Templates are strings that can be transformed into URIs after embedded variables are substituted. This document defines the

PURL Redux

thammond

thammond – 2007 July 12

In Identifiers

Seems that there’s life in the old dog yet. :~) See this post about PURL from Thom Hickey, OCLC, This extract: OCLC has contracted with Zepheira to reimplement the PURL code which has become a bit out of date over the years. The new code will be in written in Java and released under the Apache 2.0 license.
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