DLESE is the NSF funded Digital Library for Earth System Education project. DLESE collaborates with the National Science Digital Library (NSDL), which is a community of resource builder and contributors. NSDL is composed of a diverse range of education-related institutions such as universities, museums, libraries, research labs, federal agencies, professional societies, and commercial content providers.

I was an early participant with the DLESE Program Center (DPC) during its establishment. I implemented the prototype software model that performed the web-based DLESE cataloging and discovery services required for the library to become functional. The cataloging (DCS) and discovery (DDS) implementations served DLESE well for the first several years.

DLESE uses XML-defined metadata as catalog records. At that time, the DLESE metadata ontology was not formalized, and the traditional database approach couldn't provide the adaptability and responsiveness needed to support the constantly changing and evolving metadata requirements.

I used Java J2EE servlets and server pages to quickly implement a library card catalog system using the Lucene API. The application included a custom XML mapping capability that facilitated fast and easy reading and writing of XML records, and relatively easy support for changes in both the metadata structure and its ontology.

I owe a great deal to the folks that helped make the DLESE Cataloging System (DCS) a reality. Their acceptance and efforts were instrumental in making the DCS a useful usable user-friendly product.

The DCS was created as a prototype - an object to think with - as a means to demonstrate a lightweight, scalable approach to cataloging, managing, discovering and sharing XML-defined metadata-based records. The DCS was used to demonstrate and evaluate combined metadata and content-based discovery. Techniques and components from the DCS implementation were used to power the DLESE Discovery Services (DDS).

The DCS was intended to become a peer-to-peer customizable collection-building digital library application. The DCS could have become a rich and powerful tool for digital library, metadata, knowledge base and information retrieval research.

Since XML is structured, it can easily be used to load and configure processes (at startup or runtime) or read/write/share data. A properly designed system can use XML-configured processes and XML-defined protocols to become dynamically adaptable, capable of interfacing with different data sources and accommodating individual user-defined frameworks. On the fly, this type of system can potentially learn about and access remote data or services, and be shared by a distributed network of users.

DLESE was a fantastic opportunity and tremendous learning experience, but changing priorities and funding requirements precluded my further research and development of the DCS as a comprehensive digital library solution.

Lucene is now part of the Apache Software Foundation community of open-source software projects.

> goto dlese.org