Integrating Dublin Core/RDF records with MARC21

via the OCLC Connexion service at the Centre for Digital Library Research

Gordon DunsirePresented at the META-LIB final workshop

21-22 Oct 2002, Frankfurt

Overview

• The Centre for Digital Library Research• Some thoughts on metadata creation• OCLC Connexion• Workflows for metadata creation• An example in MARC21, DC and RDF• Some problems• Conclusion

Centre for Digital Library Research

• Strathclyde University, Glasgow, Scotland• Formed in Summer 1999• "… seeks to combine theory with practice in

innovative ways …" • Manages a range of projects and test-bed

services

Some CDLR projects

• INveStigating Portals for Information Resources And Learning (INSPIRAL)

• High Level Thesaurus (HILT)• Electronic Books ON-screen Interface

(EBONI)• Harvesting Institutional Resources in

Scotland Testbed (HAIRST) …

Some CDLR services

• BUBL• Scottish Collections Network (SCONE)• Co-operative Information Retrieval Network

for Scotland (CAIRNS)• Confederation of Scottish Mini-Clumps

(CoSMiC) …

Metadata projects

• Several, but two of particular interest to this presentation:

• East Dunbartonshire permanent digital archive– Methods and workflows for creating local digital

collections

• Glasgow Digital Library– Methods, etc. and services for a co-operative

digital library

Metadata creation• Determine descriptive content

– Can be more difficult that with print objects– Item level for individual objects– Collection level for all objects

• Determine headings for retrieval– Again, item and collection level

• Create structured metadata record in repository

• Export metadata as required

Item-level issues

• Descriptive elements best formulated with local expertise– E.g. local history materials

• Preliminary record creation can be restricted to item-level elements– Can be offline, say to MSAccess

Collection-level issues

• Descriptive elements and associated headings which apply to all items– E.g. copyright statement; 'series' title; placename

heading

• Possibility of (semi) automated addition to item metadata– E.g. using templates during preliminary creation,

or via software afterwards

Interoperability of headings

• Improved by using authority files• More effective and efficient if authority files

are integrated with metadata repository• Less effective if authority files are difficult to

maintain– New headings more frequent with digital objects

OCLC Connexion

• Formerly CORC (+)• Consortium subscription hosted by CDLR• CDLR developing collaborative authority

maintenance via NACO and SACO– In partnership with Strathclyde University Library

and National Library of Scotland

• OCLC also collaborating with other projects– E.g. HILT with DDC terminologies

Connexion

• Facilities for creation and mapping of metadata in Dublin Core and/or MARC21 format for digital resources– Only MARC21 records stored in WorldCat

• "Constant data" (template) facilities for DC and MARC21

• Integrated with WebDewey, LCSH and LCNAF, etc.

Possible workflows (1)

• Create item-level descriptive and heading elements locally using MSAccess forms

• Add collection-level metadata automatically using MSAccess query or Visual Basic

• Create Dublin Core <META> tags from MSAccess using Visual Basic

• Embed DC in digital object

Possible workflows (2)

• Create Connexion MARC21 template for collection-level metadata

• Use template to create item-level record• Control MARC21 headings against authority

files• Store MARC21 record in WorldCat• Reformat to DC for export

Possible workflows (3)

• Create item-level metadata locally …• Export in DC format …• Embed <META> tags in temporary HTML

documents and link to list of URLs (<100)• Use Connexion to harvest DC tags• Reformat to MARC21, apply constant data

(template), control headings …• Export in RDF format …

Example: Resource

Example: MARC21040 CX@GDLASP $c CX@

049 CX@A

245 00 Angus Mackay.

260 [Glasgow]: $b [Centre for Digital Library Research], $c 2002.

500 HTML Title: Aspect: Angus MacKay, Scottish Labour Party candidate, Edinburgh South, 1999.

540 GDL: Glasgow Digital Library.

522 Constituency: Edinburgh South.

651 0 Edinburgh (Scotland)

…

Example: DC (HTML)<meta name="DC.Title" content="Angus Mackay"> <meta name="DC.Coverage.spatial" content="Constituency: Edinburgh South"> <meta name="DC.Publisher" content="[Centre for Digital Library Research],"> <meta name="DC.Publisher.place" content="[Glasgow]:"> <meta name="DC.Date.issued" scheme="MARC21-Date" content="1999"> <meta name="DC.Description.note" content="HTML Title: Aspect: Angus MacKay, Scottish Labour Party candidate, Edinburgh South, 1999"> <meta name="DC.Identifier" scheme="URI" content="http://gdl.cdlr.strath.ac.uk/aspect/lab/labeds.htm">

…

Example: RDF

<?xml version="1.0"?> <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.0/" xmlns:dcq="http://purl.org/dc/qualifiers/1.0/"> <rdf:Description about="http://gdl.cdlr.strath.ac.uk/aspect/lab/labeds.htm"> <dc:title>Angus Mackay</dc:title> <dc:coverage>Constituency: Edinburgh South</dc:coverage> <dc:publisher>[Centre for Digital Library Research],</dc:publisher> <dc:publisher>[Glasgow]:</dc:publisher> <dc:date>1999</dc:date> <dc:description>HTML Title: Aspect: Angus MacKay, Scottish Labour Party candidate, Edinburgh South, 1999</dc:description> <dc:identifier>http://gdl.cdlr.strath.ac.uk/aspect/lab/labeds.htm</dc:identifier>

…

Some problems• MARC21 => DC/RDF is lossy

– Local MARC tags will be dropped!

• DC => MARC21 usually requires adding MARC tags after conversion

• Controlling DC headings for interoperability requires import to Connexion, then re-export

• Adding constant data in Connexion requires mediation and can only be applied to one record at a time

Conclusion

• OCLC Connexion offers a useful set of tools for format conversion and authority control which can be used flexibly in combination with external tools

• Different workflows can be employed to optimise the use of local expertise in a global environment and reduce the need for retroconversion of legacy metadata in the future.

Thank you

• And thanks to Alan Dawson of the GDL project for invaluable assistance in preparing this presentation (a.dawson@strath.ac.uk)

• CDLR: http://cdlr.strath.ac.uk• GDL: http://gdl.cdlr.strath.ac.uk• East Dunbartonshire project report:

http://www.slainte.org.uk/slicpubs/cpdalm.pdf• Connexion: http://www.oclc.org/connexion• Me: g.dunsire@napier.ac.uk (@strath.ac.uk)