Mathew Weaver

A Digital GeoLibrary: Integrating Keywords And Place Names

A digital library typically includes a set of keywords (or subject terms) for each document in its collection(s). For some applications, including natural resource management, geographic location (e.g., the place of a study or a project) is very important. The metadata for such documents needs to indicate the location(s) associated with a document – and users need to be able to search for documents by keyword as well as location. We have developed and implemented a digital library that supports – but does not require – georeferenceable documents (i.e., documents with reference to geography through the use of a textual place name). Because of their implicit spatial footprint, place names benefit from spatial reasoning and querying (e.g., to find all documents that describe work performed within a five-mile radius of a certain point) in addition to traditional keyword-based search. This paper presents the architecture for a digital library that combines spatial reasoning and selection with traditional (non-spatial) search. The contributions of this work are: (1) the use of a traditional geographic information system (GIS) for spatial processing rather than a specially tailored GIS system or a separate gazetteer and (2) the seamless integration of GIS with our thesaurus-based Metadata++ system, so users can easily take advantage of the strengths of both systems.

Using semantic components to facilitate access to domain-specific documents in government settings

We introduce the notion of semantic components that occur in domain-specific documents, discuss use of semantic components to improve document retrieval in a domain-specific collection, and present the results of two case studies.

Metadata++: A Scalable Hierarchical Framework for Digital Libraries

Metadata++ is a digital library system that we are developing to serve the needs of the United States Department of Agriculture Forest Service, the United States Department of the Interior Bureau of Land Management, and the United States Department of the Interior Fish and Wildlife Service to support natural resource managers, scientists and publics as they analyze issues and make decisions. The system provides access to institutional knowledge consisting of formal and informal agency reports and documents – including Environmental Assessments, Decision Notices, Appeal Decisions, specialist reports, and so forth. Metadata++ uses a set of hierarchically structured controlled vocabularies – with synonyms and associations – as the primary organizational framework. Users browse the hierarchy to select search terms and see the search results directly in the context of the hierarchy. In order to be useful as a digital library infrastructure, this hierarchy must be implemented in an efficient and scalable manner. This paper introduces the Metadata++ system and evaluates the performance of four different approaches to managing the hierarchy. We present a novel approach that uses a common file system with an associated indexing engine to store terms as directories (with narrower terms as subdirectories) and show how we achieve both scalability and efficiency.

Using a path-based thesaurus model to enhance a domain-specific digital library

Our research focuses on providing easy access to interdisciplinary information in the natural resource management domain [3] so users can more readily benefit from previous scientific findings, assessments, and decisions. Because of the widespread use of specialized terminology, our work focuses on extending a traditional thesaurus model [1] to properly represent and exploit the broad range of terms in a digital library designed for natural resource management.

Accelerated indexing in a domain-specific digital library

In this paper we summarize our progress and plans in two related, digital government research projects that focus on information retrieval in a domain-specific, digital library. We focus on supporting expert users in their various work tasks.