Report by Sherry Kelley, Smithsonian Institution Libraries (chair, CC:DA Metadata Task Force)
The fifth Dublin Core Metadata Workshop (DC5) was held in Helsinki, Finland on October 6-8, 1997. Approximately 75 experts representing the interests of libraries, museums, networking and digital research communities participated. Their task at this workshop, as at previous workshops, was to develop and plan implementation of a universal set of core data elements that will facilitate resource discovery on the Internet. The workshop was organized by the National Library of Finland and the Online Computer Library Center (OCLC) with support from the National Science Foundation and the Coalition for Networked Information.
Efforts to build a universal metadata element set began with a meeting at OCLC in Dublin, Ohio in March, 1995. The original plan was to provide guidance for author-generated description of World Wide Web resources. Syntax issues were not considered. The intent was to create a core element set of descriptors that would be simple to use (to be applied by non-catalogers, for example), applicable across discipline boundaries, international, and flexible enough to accommodate more elaborate semantics. Thirteen elements were proposed that were to be repeatable, optional and extensible. This set was named the Dublin Core Metadata Element Set. Elements included Creator, Title, Subject, and Publisher. Embedded or attached resource descriptions using DC elements would function as catalog records for the accompanying electronic objects, much like Cataloging In Publication (CIP) data in books. Almost three years and four workshops later, there is loose interdisciplinary, international consensus on 15 elements. Many other communities engaged in formal resource description have become involved in DC development including libraries, archives and museums. Extensibility is being addressed and Dublin Core representatives are working with other standards groups such as the World Wide Web Consortium (W3C) to develop a Web metadata architecture through the Resource Description Framework (RDF). Numerous projects using the Dublin Core Metadata Element Set have been implemented. (See http://purl.oclc.org/metadata/dublin_core/ for project descriptions and electronic addresses.) Crosswalks, or mappings, have been created for the DC elements and other metadata schemes such as GILS and MARC (see http://lcweb.loc.gov/marc/dccross.html). Clearly, the Dublin Core is emerging as a major resource description model that can function as the "lingua franca" for the diverse set of such schemes now in use for electronic resources.
Helsinki Workshop Outcomes
There were two very important achievements in Helsinki. The first was the completion of the basic version of the Dublin Core Metadata Element Set. This has been referred to variously as either DC-Lite, DC-Simple, or Minimalist DC. Stu Weibel, the chief convener and organizer of the DC workshops, refers to this accomplishment as the "Finnish finish." As a result, the list of 15 core elements can be used without qualification following simple guidelines. Further, the Dublin Core in its "Lite" version is now stablized. It can be implemented without concern that elements defined one way today will be defined differently tomorrow.
The second achievement was the group*s unanimous endorsement of the Resource Description Framework (RDF) draft specifications as the provider of the technical base, or syntactic framework, for distribution of metadata schemes across the Web. (See http://www.w3.org/TR/WD-rdf-syntax). We will soon have both the semantics and the syntax. Representatives from the DC group will continue to work with the World Wide Web Consortium RDF Task Force in further development efforts.
A third important achievement for groups like the Smithsonian Institution is the change in the scope of the descriptive elements to include physical objects. Most progress for physical description was made in the scheme definitions for the Format Element.
Working Groups will be formed to develop a more richly structured Dublin Core element set, for those in the group who dubbed themselves the "structuralists." These working groups include:
1) Sub-element Semantics. Defining sub-elements that will refine or extend the meaning of the elements without changing those meanings. These are to be limited in number and will support addition of local or experimental sub-elements. The result will be DC-Heavy, or Structured DC, as opposed to DC-Lite. Significant progress was made on sub-element refinements in Helsinki and can be seen in preliminary form in "Dublin Core Qualifiers/Substructure" by Rebecca Guenther (see http://www.loc.gov/marc/dc/qualif.html).
2) Date Sub-elements. The date element was a very contentious issue in Helsinki. Consensus on a definition was reached at the last moment, with the sub-element definitions still very much in question. The argument here will revolve around how to represent "multiple versions" of a resource: one record-many versions, or, one record-one version. If the one record-many versions model is endorsed, certain date qualifications will be needed. Requirements for the ISO-8601 Date profile will also need to be expanded.
3)Relation Element. Defining the structured relations among metadata sets which is directly related to the multiple versions issue described in 2 above.
4)Format and Resource Elements. This group will take up the problem of expanding the scope of descriptors to include non-electronic resources. This is a very important development for museum communities interested in describing physical objects and their surrogates.
DC organizers acknowledged the need to formally standardize Dublin Core elements. Some standardization has been achieved through the Internet Engineering Task Force (IETF) Request for Comment (RFC) process. New and revised RFCs resulting from Helsinki decisions will be submitted to IETF. There is also interest in the ISO/NISO standards process. It is anticipated that there will be further standardization action plans.
Other action items include the continued development of user tools and guides for Dublin Core metadata creators. An example of a wonderful creator tool is at the Nordic Metadata Project web site (http://linnea.helsinki.fi/meta/ or go to the DC home page, click on Projects, then click on Nordic Metadata Project). You will see an example of a template consisting of dialogue boxes for each element, and linked reference tools. Check the subject element to see how this works. By clicking on *subject* you get a menu of controlled vocabulary lists including AAT, MESH and LCSH. There are also two-way MARC conversion programs available. Diane Hillmann (email@example.com) has created a user guide for implementation projects. You will need to contact her directly if you are interested in getting a copy. I haven't warned her that I was going to list her as a resource, but assume that she will not mind.
List of Dublin Core elements: (see http://purl.org/metadata/dublin_core_elements) Title Contributor Source Creator Date Language Subject Type Relation Description Format Coverage Publisher Resource Rights Identifier