1. Introduction to
Dublin Core Metadata
Hannes Ebner
Knowledge Management Research group
Royal Institue of Technology (KTH), Sweden
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2. Dublin Core Metadata
Initiative (DCMI)
http://dublincore.org
• General descriptive metadata
• Dublin Core Abstract Model
– Information model independent of format
• 1998: Dublin Core Element Set 1.0, IETF RFC2413
• 2000/2001/2003: EU/US/ISO recommendation/standard
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3. DCMI
• Metadata Terms and Element Sets
• Resource: "Anything that has an identity"
– Ideal: URI for everything that is described
• Resource Model: each value is
– physical (books, people, etc)
– digital (documents, images, etc) or
– conceptual (time, subjects, etc) entity
• Resource Model: built on top of the W3C Resource
Description Framework (RDF)
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4. Interoperability
• Set of interoperable metadata standards
• Used for metadata harvesting (OAI-PMH): requirement to
support DC
• RSS 1.0: the most flexible feed format (not widely
adopted)
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5. Dublin Core Elements -
Simple Dublin Core
identifier, creator, contributor, publisher, title,
description, language, subject, coverage, format,
type, date, relation, source, rights
• 15 elements
• All optional
• Repeatable
• Domain independent
• dc namespace
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7. DCMI Terms -
Qualified Dublin Core
• DCMI Terms
• dcterms namespace
• Element refinements (more specific)
• Encoding schemes (recommended): controlled vocabularies or special
format
• 55 elements and attribute/value pairs
Examples:
Language
<dc:language>English (UK)</dc:language>
vs
<dcterms:language scheme="ISO 639-1">en-gb</dcterms:language>
Date
<dc:date>November 2nd, 2009</dc:date>
vs
<dcterms:date scheme="W3CDTF">2009-11-02</dcterms:date>
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8. Dublin Core in RDF
• DCAM maps easily into RDF (built on top of it)
• Semantic Web and Linked Data
• Combinable with e.g. OWL, SKOS, etc
• Helps machines processing data by maintaining semantics
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9. Custom Extensions to DC
• Mappings to DC where possible
• Thorough documentation necessary
• Example: LOM and DCAM
– IEEE LTSC / DCMI Task Force draft for mapping LOM to
DCAM
– First implementation by KTH
– Used within Organic.Edunet
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10. Summary
• 15 metadata elements
• More than 50 DCMI approved properties
• Ideal for Semantic Web and Linked Data based
repositories
• Custom mappings to DCAM possible
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