7 - Indira Gandhi Centre for Atomic Research

thesauri and controlled vocabularies are widely used as a basis for both resource
description/discovery and information management purposes. The minimum metadata sets
are required for harvesting such as Document Identifier, Title, Description, and Subjects.
OAI-PMH (Open Archives Initiative Protocol for Metadata Harvesting) is mechanism for
harvesting XML-formatted metadata from distributed collections of metadata. This
Protocol provides the basic information discovery environment that relies on transferring
metadata en masse from one server to another in a network of information systems based
on the open standards HTTP (Hypertext Transport Protocol) and XML (Extensible
Markup Language).
Repository
(Data Provider)
Repository
(Data Provider)
Repository
(Data Provider)
Repository
(Data Provider)
Harvesting
End user
Search and Retrieval of
Service Provider
Metadata
Database
Metadata
Fig.6 Basic approach of OAI-PMH
The metadata that is harvested may be in any format that is agreed by a community (or by
any discrete set of data and service providers), although unqualified Dublin Core is
specified to provide a basic level of interoperability. Thus, metadata from many sources
can be gathered together in one database, and services can be provided based on this
centrally harvested or "aggregated" data. The link between this metadata and the related
Content is not defined by the OAI protocol. It is important to realize that OAI-PMH does
not provide a search across this data; it simply makes it possible to bring the data together
in one place.
4. Storage & Retrieval
There is an increasing need on providing search on the full text of digitized documents in
addition to the bibliographic level. It is required to develop a storage & retrieval system
which takes the advantage of structural knowledge from the assigned index terms on
various search fields. There is an increasing need to research on the impact of this
capability and to develop a storage and retrieval system, which takes advantage of
structural knowledge. The integration of structural and textual information can allow one
to achieve a higher quality of retrieval results.
Standard Generalized Markup Language (SGML) provides a very powerful tool for
describing document. Based on SGML, Hypertexts Markup Language (HTML),
Hypermedia/Time-based Structuring Language (HyTime), and Text Encoding Initiative
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