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Metadata Formats

<dc:date>1845.</dc:date>
<dc:language>eng</dc:language>
<dc:description>The Astronomical and Meteorological observations of the 1842 expedition,
which form p. 585–693 of the Senate edition (Senate ex. doc. 174) are not included in this.</
dc:description>
<dc:subject rdf:resource=“http://www.loc.gov” />Discoveries in geography</dc:subject>
<dc:subject rdf:resource=“http://www.loc.gov” />Paleontology</dc:subject>
<dc:subject rdf:resource=“http://www.loc.gov” />Botany</dc:subject>
</rdf:Description>
</rdf:RDF>

In the above example, RDF elements are used to define the ontologies
utilized by the controlled terms found within the record. In this case, I’ve
placed representative URIs (Universal Resource Identifiers) identifying the
creator and subject elements. So while the URIs provided will not resolve to
anything meaningful, this does capture the idea behind the RDF markup.
Ideally, the rdf:resource URIs would resolve to the ontology, which could
then be parsed to build relationships between the terms utilized in this
record and the terms found within the ontology. Of course, this is just a
simple example of how RDF could be utilized to represent a Dublin Core
record. The draft formalized in 2008 provides much more detail illustrating
the many different levels of RDF encoding that can be supported and rec-
ommended for use and has been used as a jumping off point for additional
specification development, specifically the LRMI Community (http://lrmi.
dublincore.org/) efforts to develop new classes to expand schema.org’s
description of learning resources. But we can go further. We can incorpo-
rate multiple schemas using various serializations to represent wide ranges
of data. For example, let’s use the example above, but incorporate multiple
metadata schemas.

<?xml version=“1.0” encoding=“utf-8”?>
<rdf:RDF xmlns:rdf=“http://www.w3.org/1999/02/22-rdf-syntax-ns#” xmlns:dc=“http://purl.org/dc/
elements/1.1/”
xmlns:dcterms= “http://purl.org/dc/terms/”
xmlns:relators=“http://id.loc.gov/vocabulary/relators/”>
<rdf:Description>
<dc:title>Report of the exploring expedition to the Rocky Mountains in the year 1842 : and to
Oregon and north California in the years 1843–44 /</dc:title>
<dc:creator rdf:about=“http://id.loc.gov/authorities/names/n50025411”>
Frémont, John Charles,1813–1890
<relators:aut rdf:about=“http://id.loc.gov/vocabulary/relators/aut”>author</relators:aut>
</dc:creator>
<dc:contributor rdf:about=“http://id.loc.gov/authorities/names/n84075762”>
Torrey, John,1796–1873
<relators:ctb rdf:about=“http://id.loc.gov/vocabulary/relators/ctb”>contributor</relators:ctb>
</dc:contributor>
<dc:contributor rdf:about=“http://id.loc.gov/authorities/”>
Hall, James,1811–1898
<relators:ctb rdf:about=“http://id.loc.gov/vocabulary/relators/ctb”>contributor</relators:ctb>
</dc:contributor>
<dc:contributor rdf:about=“http://id.loc.gov/authorities/names/n79069640”>
United States. Army Corps of Engineers
(Cont.)
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