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DIGITAL LIBRARIES AND ENVIRONMENTAL INFORMATION

DIGITAL LIBRARIES AND ENVIRONMENTAL INFORMATION. Terence R. Smith Alexandria Digital Library Project. OVERVIEW. DL development activities NSF supported activities Alexandria Digital Earth Prototype (ADEPT) NSDL model of a distributed DL Extension to a heterogeneous DL

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DIGITAL LIBRARIES AND ENVIRONMENTAL INFORMATION

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  1. DIGITAL LIBRARIES AND ENVIRONMENTAL INFORMATION Terence R. Smith Alexandria Digital Library Project

  2. OVERVIEW • DL development activities • NSF supported activities • Alexandria Digital Earth Prototype (ADEPT) • NSDL model of a distributed DL • Extension to a heterogeneous DL • Example of distributed DL for environmental information

  3. NSF-SUPPORTED DL ACTIVITIES • DLI-1 • 94-98 • 6 projects • DLI-2 • 99-05 • About 30 projects • NSDL • 00-06 • About 70 projects • DLESE • 99-? • 1 project

  4. COMPONENTS OF A DISTRIBUTED DL • SINGLE SYSTEM • Client(s) • multifunction • Search middleware • Collection(s) • Item metadata • Collection metadata • Items • Collections building services • Metadata entry • Other metainformation services • Gazetteers, thesauri, knowledge bases,… • MULTIPLE (HETEROGENEOUS) SYSTEMS

  5. ADEPT GOALS • Goals • distributed digital library for georeferenced information • services supporting DL federation and interoperation • personalized “learning spaces” • Scalability • many collections • collections, very large to very small • extreme heterogeneity

  6. Z39.50+MARC+ AACR2 SDLIP increasing functionality GDLIP HTTP+ HTML OAI SOAP increasing structure, standardization increasing generality INTEROPERABILITY LANDSCAPE ADEPT

  7. item item item ADEPT ARCHITECTURE (HIGH-LEVEL) client • uniform client services • item-level metadata mapped to search buckets (high-level, typed fields with rich search semantics) • uniform collection- level metadata includes coverage histograms • plugins support common collection implementations collection discovery service middleware RDBMS Z39.50 proxy collection collection personal

  8. Unifying threads: common collection-level metadata “bucket” framework for item-level metadata Buckets transparent metadata aggregation system = Dublin Core plus: search-oriented fields strong typing search semantics explicit representation of metadata mappings Items… map native metadata to buckets Collections… index mapped metadata aggregate mappings compute statistics Collection discovery service… indexes collection-level metadata & statistics CORE ARCHITECTURE (2/2)

  9. ranking methods access control mechanisms ADEPT IMPLEMENTATION C L I E N T web browser JIGI SDLIP proxy HTTP web intermediary/ XMLHTML converter HTTP transport RMI transport HTTP XML M I D D L E W A R E client-side services (Java classes) core functionality access control (service- and collection-level)query fan-out & results mergingquery result rankingresult set caching configuration file server-side interface (Java interfaces) XML S E R V E R JDBC Bucket99 driver query translator proxy driver RDBMS group driver configuration files, scripts

  10. REFERENCE SERVICES • Gazetteer protocol developed • collaborated with ESRI, NGS • formal definition of gazetteer • characterizes gazetteer services • Lots of interest • within and outside InterLib: USGS, NASA, UMass, SRI,... • our gazetteer • protocol itself • Use of gazetteer in semantic mappings: geoinformation  text • Prelude to additional reference services • thesaurus/ontology services

  11. A DISTRIBUTED DL FOR EI • NSDL core integration system (CIS) model • Central metadata repository • Common metadata standards • Dublin core and others • Integration of ADEPT nodes • Conversion to ADEPT search buckets • ADEPT middleware available

  12. EXTENDING CORE CIS ARCHITECTURE • Extending the spectrum of search interoperability • collections with non-DC metadata schemas • distributed and heterogeneous collections • richer search functionality • geospatial search, thesaurus/concept space search, ... • Supporting the creation of new and personalized collections • Providing access to thesaurus and gazetteer services

  13. EXTENDING SEARCH INTEROP metadata repository harvest OAI portal 2. harvest & interpret 3. h & i metadata ADEPT 1. map ADEPT collection discovery ADEPT client ADEPT per collection provider

  14. THREE SETS OF SERVICES • Search over heterogeneous collections • mapping between OAI metadata and ADEPT search buckets • installations of ADEPT middleware • Collection building services • metadata entry tool for ADN metadata content standard • personalized collections of existing and new metadata • Information access services • gazetteer and thesaurus protocols • convert textual  geospatial references

  15. SUMMARY • Infrastructure and systems exist to build distributed DL for environmental information • Model of NSDL + ADEPT system • Example task: LTER DL integration

  16. DLESE interactions • Adoption of the ADEPT architecture • middleware • RDBMS-based and local collections • Co-development of ingest tools • resource cataloger • spatial footprint specification tool • metadata/collection administration support • Co-development of a metadata content standard for learning objects • Exposure to user community • GDLIP

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