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Pete Johnston, Eduservpete.johnston@eduserv.org.uk

http://www.eduserv.org.uk/research/

Miscellaneous Usage Issues

DCMI Usage Board, DC-2009, Seoul, Korea

16 October 2009DCMI Usage Board, DC-2009, Seoul, Korea 2

Simple DC

16 October 2009DCMI Usage Board, DC-2009, Seoul, Korea 3

Simple DC

• Described informally in various DCMI documents

• From viewpoint of DCAM/Singapore Framework

• Either– A “pattern” for constructing description sets

– i.e. a Description Set Profile

• Or– A DC Application Profile, which includes a DSP

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Simple DC as DSP: Suggestion 1

• DSP expression of “traditional” “Simple DC” pattern

• Description set contains one description, of resource of any type

• For each statement in description– Property URI must be from list of 15 properties of DCMES

(i.e http://purl.org/dc/elements/1.1/title etc)

– Literal value surrogate required• SES URI not permitted

• Language tag optional

16 October 2009DCMI Usage Board, DC-2009, Seoul, Korea 5

Simple DC as DSP: Suggestion 2

• Singapore 2007 Proposal (Mikael/Tom)• DSP expression of a “modernised” “Simple DC” pattern• Description set contains one description, of resource of

any type• For each statement in description

– Property URI must be from list of 15 “new” properties of DC Terms (i.e http://purl.org/dc/terms/title etc)

– Type of surrogate on case by case basis, depending on range

– For literal value surrogates• SES URI not permitted• Language tag optional

– For non-literal value surrogates• Value URI not permitted• VES URI not permitted• One value string permitted

– SES URI not permitted– Language tag optional

16 October 2009DCMI Usage Board, DC-2009, Seoul, Korea 6

Issues

• Are we labelling a DCAP or a DSP?

• Both “patterns” are “valid” DSPs

• What do we want to achieve?– To formalise the “traditional” pattern?

– To develop a “modernised” pattern (based on new terms, ranges etc)?

– Both?

• Which do we want to label “Simple DC”?

• And if we do both, what do we label the other pattern?

16 October 2009DCMI Usage Board, DC-2009, Seoul, Korea 7

Issues

• “Dumb-down”?– Generation of “Simple DC” description set?

• If “Simple DC” = “traditional” pattern– Does “dumb-down” imply mapping non-literal to

literal?

• If “Simple DC” = “modern” pattern– Non-literal supported in target so no need for

mapping

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Doc:D

“5 mins”dcterms:extent

Doc:D “5 mins”

dc:format

Dumb-down to “traditional” Simple DC

16 October 2009DCMI Usage Board, DC-2009, Seoul, Korea 9

Doc:D

“5 mins”dcterms:extent

Doc:D

dc:format

Dumb-down to “modern” Simple DC

“5 mins”

16 October 2009DCMI Usage Board, DC-2009, Seoul, Korea 10

Discussion

• “Simple DC” as “traditional” pattern– Dovetails with existing informal documentation– “Intuitive” fit with e.g. oai_dc XML format– Ignores modernisation of terms

• Continues to promote “blanket” usage of literal values

– “Dumb-down” complexity?

• “Simple DC” as “modernised” pattern– Recognises modernisation of terms

• Promotes appropriate usage of literal/non-literal values

– “Dumb-down” simpler?– Differs from existing informal documentation– Less “intuitive” fit with e.g. oai_dc XML format

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Use of dcterms:identifier

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Use of dcterms:identifier

• Use literal values – e.g. URI as literal value, not “value URI”

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Use of dcterms:identifier

• Within a single description, use dcterms:identifier only for identifiers of the described resource

• Take care with resource/representation & resource/description (httpRange-14) issues

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Use of dcterms:identifier

• Differentiating “identifier syntaxes”– Where represented as URI

• use SES = dcterms:URI (or xsd:anyURI)

• Don’t use SES = example:URN, example:UUID (etc) as these are all URIs

– Where represented as non-URI literal• use SES?

– SES = example:ASIN (etc)

• (but e.g. BIBO uses subproperties)

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Use of dcterms:identifier

• Differentiating “categories/purposes of identifier”

– Subproperties for e.g.• “local identifier”?

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Miscellaneous Usage Issues

Title slide photo “Seoul Gyeongbok Palace” by Flickr user storyvillegirlSee http://www.flickr.com/photos/bibbit/2948779230/Made available under CC Attribution-Share-Alike 2.0 license

16

Octo

ber 2

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Pete Johnston, Eduservpete.johnston@eduserv.org.uk

http://www.eduserv.org.uk/research/

Dublin Core Description Set Profiles

DC-2009, Seoul, Korea