[OAI-implementers] Archaeological Metadata

Alan Kent ajk@mds.rmit.edu.au
Tue, 12 Nov 2002 10:54:45 +1100

On Mon, Nov 11, 2002 at 12:29:48AM -0500, Rohit Kelapure wrote:
> I need to expose metadata related to Archaeological artifacts/records. 
> ...  A family of metadata 
> standards is required to describe a single resource like Qualified Dublin 
> core, FGDC, GCMD, DIF etc. ...  Would RDF be the correct 
> approach to take here or would it be better to expose each resource in 
> different metadata formats.

My personal opinion is that the OAI model is for you to use whatever
format you think best internally for your 'items' of information - RDF
being a completely valid choice if it can capture the information of
all the different formats you want - but then transform items into
the appropriate 'record' formats for delivery.

OAI mandates that all repostories be able to return items in the oai_dc
record format (metadataPrefix=oai_dc). OAI defines the XML Schema for this
format. But you are certainly allowed to support other formats for
the one item. This is part of the OAI model.

The idea as I understand it is to use whatever you need internally,
but use standard formats for delivery. For example, if appropriate,
support oai_dc (unqualified Dublin Core), Qualified Dublin Core, FGDC,
GCMD, DIF, etc as different record formats (metadataPrefix=) from
the one repository. You only have one 'item' in your database,
but when you deliver it transform it to whatever record format was
requetsed. That way people accessing your data who only
understand FGDC get the data in the format they want. They don't
have to understand your internal format (be it RDF or anything else).

You can always choose to also make your RDF available as well as
one of the record formats.

> What is the support provided by OAI for RDF?

I have not heard of anyone using RDF with OAI. As long as you can define
an XML Schema for the XML you are returning, it should be fine though.

*Personally* I find RDF pretty complex to use in practice. I see it as
a bad sign that it has been around for some time, but never really
taken off. To me its an indication that its too complex for the average
user. This is not to say its not good, just a personal observation.
I tend to encode my data in whatever format is most appropriate for
the data, then use XSLT to transform the data into whatever other
format I need. I personally never found benefit in RDF for my
original data source - but that may be just because of the tools
I am using.

Alan Kent (mailto:Alan.Kent@teratext.com.au, http://www.mds.rmit.edu.au/~ajk/)
Project: TeraText Technical Director (http://teratext.com.au) InQuirion Pty Ltd
Postal: Multimedia Database Systems, RMIT, GPO Box 2476V, Melbourne 3001.
Where: RMIT MDS, Bld 91, Level 3, 110 Victoria St, Carlton 3053, VIC Australia.
Phone: +61 3 9925 4114  Reception: +61 3 9925 4099  Fax: +61 3 9925 4098