Dublin CoreElements & Uses

15 metadata elements for the description of resources…

especially digital resources.

http://dublincore.org/

Jody DeRidder, Digital Libraries IS 565, Spring 2007

1) What’s a “resource”? A resource is anything that has identity. Familiar examples include

an electronic document, an image, a service (e.g., "today's weather report for Los Angeles"), and a collection of other resources.

2) How do “elements” apply to “resources”?

An Element is a characteristic that a resource may “have”, such as a Title, Publisher, or Subject.

3) What if I have more than one version of this resource?

Then you have more than one “instantiation”, and you will need more than one set of Dublin Core elements.

What do you mean, I need another set of elements?

Four of the basic Dublin Core elements relate to the “instantiation” of the resource:

Language: A language of the resource. Recommended best practice is to use a controlled vocabulary such as ISO 639-2. Example: “eng” for English.

Identifier: An unambiguous reference to the resource within a given context. Recommended best practice is to identify the resource by means of a string conforming to a formal identification system, such as an ISBN.

Date: A date associated with the creation or availability of the resource. Recommended best practice is defined in a profile of ISO 8601 that includes (among others) dates of the forms YYYY and YYYY-MM-DD.

Format: The file format, physical medium, or dimensions of the resource. Examples of dimensions include size and duration. Recommended best practice is to use a controlled vocabulary such as the list of Internet Media Types [MIME]. Example: image/jpeg.

So two instantiations of the same resource will require two different metadata records!! Examples: you have a text in both French and English; or an image of a museum object as well as a 3-D video of it… or two versions of a scanned photograph.

But what describes the content?

Title: The name given to the resource.

Description: An account of the content of the resource. Description may include but is not limited to: an abstract, table of contents, reference to a graphical representation of content or a free-text account of the content.

Subject: The topic of the content of the resource. Typically, a subject will be expressed as keywords or key phrases or classification codes that describe the topic of the resource.

Coverage: The extent or scope of the content of the resource. Coverage will typically include spatial location (a place name or geographic co-ordinates), temporal period (a period label, date, or date range) or jurisdiction (such as a named administrative entity).

Source: A reference to a resource from which the present resource is derived. The present resource may be derived from the Source resource in whole or part.

Type: The nature or genre of the content of the resource. Type includes terms describing general categories, functions, genres, or aggregation levels for content.

Relation: A reference to a related resource.

What about who made it?

That falls under “Intellectual Property”:

Creator: An entity primarily responsible for making the content of the resource. Examples of a Creator include a person, an organization, or a service.

Contributor: An entity responsible for making contributions to the content of the resource. Examples of a Contributor include a person, an organization or a service. Typically, the name of a Contributor should be used to indicate the entity.

Publisher: The entity responsible for making the resource available. Examples of a Publisher include a person, an organization, or a service. Typically, the name of a Publisher should be used to indicate the entity.

Rights: Information about rights held in and over the resource. Typically a Rights element will contain a rights management statement for the resource, or reference a service providing such information. Rights information often encompasses Intellectual Property Rights (IPR), Copyright, and various Property Rights. If the rights element is absent, no assumptions can be made about the status of these and other rights with respect to the resource.

All the 15 elements of Simple Dublin Core

Instantiation: Date Format Identifier Language

Content: Title Description Coverage

Relation Source Subject Type 

Intellectual Property: Contributor Creator Publisher Rights

Any element may be used as many or as few times as needed; there is no order to their use. You must refer to the schema in the namespace at the top of the file. (The schema details what elements may be used and how.)

Example schema reference:

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:dc="http://purl.org/dc/elements/1.1/"

And if I want more?

What are Dublin Core "Qualifiers"? Terms that extend or refine the original 15 elements of the Dublin Core

Metadata Element Set. There are 2 classes:

1) Element Refinement: A refined element shares the meaning of the unqualified element, but with a

more restricted scope.

2) Encoding Scheme: An encoding scheme aids in the interpretation of the element value, by

referring the user to the controlled vocabulary, formal notation, or parsing rules used.

Qualifiers must follow the "Dumb-Down" principle.

What’s the Dumb-Down Principle?

Qualification is therefore supposed only to refine, not extend the semantic scope of an Element. They simply provide more specific information.

According to this rule, the client should be able to ignore any qualifier and use the value as if it were unqualified.

This way, if the software application can’t support the qualifier terms, it ignores the qualifier and uses the value in the tag as if it were in the more general tag.

The value is still valid in the more general tag, and still is useful for discovery.

Example: “dcterms:temporal” refines “dc:coverage.”

<dcterms:temporal>The Great Depression, 1929-1939</dcterms:temporal> becomes<dc:coverage>The Great Depression, 1929-1939</dc:coverage>

There is nothing to indicate now that it is a time period… but it’s still “coverage”.

Type of Qualifier

Element Example Qualifiers

Element Refinement

Description Abstract, tableOfContents

Coverage Spatial, Temporal

Date Available, Created, dateCopyrighted, dateAccepted, dateSubmitted

Relation hasPart, hasVersion, isPartOf, isReferencedBy, isReplacedby, isVersionOf

Encoding Schemes

Subject DDC (Dewey Decimal Classification),

LCC (Library of Congress Classification),

LCSH (Library of Congress Subject Headings),

MESH (Medical Subject Headings)…

Language ISO639-2 (such as eng, for English), RFC1766 (such as en-us for US English)

Date W3CDTF (such as 1997-12-04 for 4 Dec. 1997) Type DCMIType, such as: Collection, Dataset, Event, Image,

InteractiveResource, MovingImage, PhysicalObject, Service, Software, Sound, StillImage, Text.

Some example qualifiers…

How do people use the DC element set?

They are used to create records for resources so that those resources can be searched for and retrieved using the Dublin Core elements.

So you will see them as XML for computer processing, and as labels of fields to search in an interface (the results of that processing).

Web Feeds, such as RSS <dc:title> Slashdot</dc:title> <dcterms:alternative> News for nerds, stuff that matters<dcterms:/alternative> <dc:identifier rdf:resource="http://slashdot.org" />

HTML meta and link elements for web pages <meta name = "DC.Title" content = "Crime and Punishment"> <meta name="DCTERMS.bibliographicCitation" content="Library and Information Science Research 22(3), 311-338" /> <link rel="DC.relation" hreflang="de" href="http://www.example.org/de/" />

RDF for semantic web applications <rdf:Description> <dc:title> Internet Ethics</dc:title> <dc:creator> Duncan Langford</dc:creator> <dc:identifier> ISBN 0333776267</dc:identifier> </rdf:Description>

They are used to create records for resources so they can be searched for and retrieved…. Such as in digital libraries! (a terrific example: OAIster.)

Example xml record <record xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:dcterms="http://purl.org/dc/terms/"> <dc:title> An Impression of the Pi Beta Phi Settlement School and its Vicinity</dc:title> <dc:creator> Moorehead, Rosemary</dc:creator> <dcterms:dateCreated> 1936-11-07</dcterms:dateCreated> <dc:type> Mixed material</dc:type> <dc:type> Scrapbook</dc:type> <dc:format xsi:type="dcterms:IMT"> image/jpeg</dc:format> <dc:description> Scrapbook on the Pi Beta Phi Settlement School and Gatlinburg area. Compiled by Pi Beta Phi teacher Rosemary Moorehead. </dc:description> <dc:subject> Student life</dc:subject> <dc:subject> Settlement schools </dc:subject> <dc:subject> Gatlinburg, Tennessee</dc:subject> <dc:subject> Pi Beta Phi Settlement School</dc:subject> <dc:subject> Expansion and Growth of Pi Beta Phi Settlement School, 1928-1943</dc:subject> <dc:source> Great Smoky Mountains Regional Project, The University of Tennessee Libraries. </dc:source> <dc:rights> For rights relating to this resource, visit: http://idserver.utk.edu/?

id=200500000001941</dc:rights> <dc:identifier> rms00000</dc:identifier> <dc:relation> From Pi Beta Phi to Arrowmont:

http://idserver.utk.edu/?id=200500000001049</dc:relation> <dc:language xsi:type="dcterms:ISO639-2"> eng</dc:language></record> This record is currently viewable online here….

Created by Melanie Feltner-Reichert for the Arrowmont Project at UT Libraries

Example online represenatation

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