1. DDC Update: Formats, WebDewey 2.0, and Linked Data
Joan S. Mitchell
Editor in Chief, DDC
OCLC
Dewey Translators Meeting
IFLA 2009, Milan
25 August 2009

2. Changes in the Representation of the DDC
Adoption of the MARC 21 classification and authority formats for the representation of the DDC in the new Editorial Support System (ESS)
Change in the DDC distribution format from ESS XML to MARCXML
Conversion of data format in the Pansoft translation support software to MARCXML
Changes in the MARC 21 formats

3. Changes in the MARC 21 Formats
MARC Proposal No
Submitted jointly by the Dewey editorial team, Deutsche Nationalbibliothek (DNB), Library of Congress, and OCLC
Added to MARC 21 in Update No. 9 (October 2008)
Implemented by OCLC in WorldCat on 16 August

4. Changes in MARC 21 Bibliographic Format: 082, 083, 085
082 Dewey Decimal Classification Number (new subfields)
083 Additional Dewey Decimal Classification Number
085 Synthesized Classification Number Components

5. 082 Dewey Decimal Classification Number (new subfields)
$m - Standard or optional designation (NR)
a (standard)
b (optional)
$q - Assigning agency (NR)
Used with second indicator 4 (Assigned by agency other than LC)

6. 082 Dewey Decimal Classification Number (new subfields): Example
Feehan, Margaret, 1962-
The serpent’s veil
LCSH: Canadian fiction—20th century
$a $2 22 $m a
$a C $2 22 $m b $q CaOONL

7. 083 Additional Dewey Decimal Classification Number
To be used for Dewey numbers, including internal and external table numbers, added for subject access

8. 083 Additional Dewey Decimal Classification Number: Example
Historic villas of Lake Maggiore
$a $2 22
$a $2 22

9. 085 Synthesized Classification Number Components
To show how a built Dewey number has been built and to specify the component elements

10. 085 Synthesized Classification Number Components: Example
Artistic themes in literature
$8 1 $a $2 22
085 ## $8 1.1 $b $a $c $z 3C $s 357
Artistic themes
Collections of literary texts from more than two literatures displaying specific features

11. WebDewey 2.0 Design Goals Modern interface
Support for search, browse, number building, and personalization
Generic user interface script to allow use of more than one language version and connection to terminology sets
Local controls (links to terminology sets, display of hierarchy, connections to OPACs, etc.)

12. Proposed Welcome Screen

13. Proposed Advanced Search Screen

14. Proposed Results Screen with Notes, Terms, and Work Area
Search Browse Add User note Add Institution Note Link to OPAC Help
Main Classes Tables More
Build number
(User created notes)
Relative Index
Mapped Terms
English
LCSH

15. Dewey Web Services http://dewey.info
Experimental space for linked DDC data
Initial linked data set: DDC Summaries in 9 languages  
Features:
Classification semantics encoded in SKOS
Actionable URIs for every DDC class
Representations for humans (HTML) and machines (RDF)
The linked data is available under a Creative Commons  BY-NC-ND license (more permissions are available here) 
We’ve just launched dewey.info, an experimental space for linked data.
The initial data set available is a linked data version of the DDC Summaries (the top three levels of the DDC) in nine languages.
The classification data is encoded in SKOS (Simple Knowledge Organization System) with actionable URIs (Uniform Resource Identifiers) for each DDC class.
The service responds to regular HTTP requests (in the form of Dewey URIs) with either a machine - (RDF) or human-readable (HTML) presentation.
Publishing parts of Dewey as linked data means that any application or resource description can establish live links into the DDC, instead of just using the Dewey number.
The linked data is available under a Creative Commons BY-NC-ND license—this license allows linking, reuse, and experimentation with the data for noncommercial purposes. We’re looking forward to hearing about creative applications of the linked data.

16. http://dewey.info/class/641/about/ (human-readable version)

17. http://dewey.info/class/641/about.rdf (machine-readable version)