Sharing Knowledge: Scientific Communication - SSOAR

MPRESS - transition of metadata formats 159
the first distributed service that made use of this idea in order to improve
retrieval.
Nowadays the W3C recommends the use of RDF to express descriptions of
documents. This enforces systems like MPRESS to change their architectures in
order to be able to handle RDF and former formats.
The paper describes the architecture of MPRESS and the philosophy of RDF
in comparison with the HTML META tag, in this way it explains the difficulties
that arise during the transition to RDF and how these difficulties are being
handled.
Harvest working with plain metadata
The system MPRESS/Math-Net.preprints is an index for mathematical preprints,
it is not a full text archive. The idea is to create an index of mathematical
preprints without storing them on one central preprint server.
Usually central archives offer search mechanisms, but the preprints on departmental
servers are at most searchable via Web-Robots of the Alta Vista type.
Since the number of scientific mathematical material is very small it is nearly
impossible to find mathematically relevant papers in the Web via those general
search engines. A solution to this problem is to generate an index of the distributed
documents. MPRESS/Math-Net.preprints is such a system. Currently
MPRESS compiles links to about 50,000 mathematical preprints in the world.
The quality of the retrieval in MPRESS is mainly founded on the good use of
metadata.
HTML Metadata in harvest
The metadata set is based on the metadata set that the American Mathematical
Society (AMS) created for their preprint server (http://www.ams.org/preprints).
The AMS stored these metadata in ASCII format without using any particular
scheme.
In MPRESS we store these metadata inside HTML documents that serve as
title pages for the preprints. Obviously it is necessary to offer information like
“author” and “title” in a way that is independent from the subject “mathematics".
The Dublin Core initiative [Kunze, 1999] offers such a scheme which is
user-friendly and allows subject specific extensions.
A full list of the used items and the current encoding of these items can be
found at http://www.math-net.de/project/metadata/preprint.html, as there are
the name of the author, the email address of a contact person, Mathematical Subject
Classification (MSC) codes, an abstract, notes, the date of creation and last