This Services track project is a collaboration of investigators from the University of Washington (0532828) and Cornell University (0532854) who are developing and deploying a metadata registry service to complement the NSDL Central Metadata Repository. The registry is based on the open-source Dublin Core Metadata Initiative (DCMI) Registry application and enables multiple diverse collection providers and other NSDL projects to identify, declare, and publish their metadata schemas (element/property sets) and schemes (controlled vocabularies). Furthermore, the project provides support for registration of schemes and schemas for use by human and machine agents, as well as support for the machine mapping of relationships among terms and concepts in those schemes (semantic mappings) and schemas (crosswalks). The intellectual merit of the project lies in its use of distributed registries of metadata schemes and schemas to improve services to users in an increasingly heterogeneous Web digital library universe; and it points to an environment where important semantic connections between diverse communities and their vocabularies are effectively enabled. The broader impact of the project is its generalization of registry software and implementation beyond centrally controlled metadata schemas. This enables the distribution of appropriate control and management into the hands of vocabulary creators and maintainers, thus facilitating the potential to overcome economic and legal barriers that have prevented the anticipated growth of registries and distributed registry networks.
