1. Introduction to
Dublin Core Metadata
Hannes Ebner
Knowledge Management Research group
Royal Institue of Technology (KTH), Sweden
1

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
2

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)
3

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)
4

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
5

6. DCMI Terms -
Qualified Dublin Core
abstract, accessRights, accrualMethod,
accrualPeriodicity, accrualPolicy, alternative,
audience, available, bibliographicCitation,
conformsTo, contributor, coverage, created,
creator, date, dateAccepted, dateCopyrighted,
dateSubmitted, description, educationLevel, extent,
format, hasFormat, hasPart, hasVersion, identifier,
instructionalMethod, isFormatOf, isPartOf,
isReferencedBy, isReplacedBy, isRequiredBy, issued,
isVersionOf, language, license, mediator, medium,
modified, provenance, publisher, references,
relation, replaces, requires, rights, rightsHolder,
source, spatial, subject, tableOfContents,
temporal, title, type, valid
6

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>
7

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
8

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
9

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
10

11. Links
The Dublin Core Metadata Initiative
http://dublincore.org
DCMI Metadata Basics
http://dublincore.org/metadata­basics/
DCMI Metadata Terms
http://dublincore.org/documents/dcmi­terms/
Joint DCMI/IEEE LTSC Taskforce
http://dublincore.org/educationwiki/DCMIIEEELTSCTaskforce
11