1. Alexandria Digital Library Greg Janée gjanee@alexandria.ucsb.edu http://www.alexandria.ucsb.edu/

2. Outline zOverview zData zUser Interface zArchitecture zDevelopment in progress zSummary

3. Overview zADL is one of the 6 DLI/1 projects zFocus is on georeferenced information zHolistic approach: address all aspects of the problem of digital library creation zEvolution of prototypes: ¶GIS-based ·Web-, HTML-based ¸Latest: Java client with standardized middleware interfaces zSlated to become part of the California Digital Library

4. Data zGeospatial and georeferenced materials zApproaching 1M catalog holdings, 6M gazetteer entries, 0.5TB storage zEmphasis on data heterogeneity ywide variation in content type: aerial photographs, U.S.G.S. products, scientific datasets, gazetteer data including seismic and volcanic activity, bibliographic references, etc. ywide variation in metadata content: FGDC, USMARC, numerous ad hoc content standards ywide variation in geographic extent and resolution

6. User interface zJava client applet/application zMaintains session and workspace zOffers both spatial and textual paths into the system

7. User interface

8. Query history and organization of results Current result set Thumbnail image Metadata synopsis

9. User interface Metadata report: Access report is similar; includes “browse graphic,” access and use constraints, and hypertext link to actual file

10. Architecture z3-tier, client-server architecture zAdmits multiple clients, multiple collection servers zDriving feature is the middleware server, which presents standard, collection- independent services to clients

11. Architecture

12. zSearch buckets: yAbstract, searchable indexes ySimilar to GILS and Dublin Core, but buckets define the allowable content and search semantics, and they are optimized for geospatial searching yDesigned to be easy for collections to populate zLocation, Time, Type, Format, Originator, Assigned terms, Free terms, Identifier

13. Development in progress zAdditional clients, e.g., Z39.50 zJava servlet-based middleware zBetter delineation of middleware-server interface zAdditional types of collections: yGateways (e.g., Z39.50) yRemote collections (e.g., existing, traditional library catalogs)

14. Development in progress Operations DB Maintenance DB Gateway Remote collection Remote collection Middleware Middleware-driver API HTTP driver ODBC driver Middleware Middleware-driver API HTTP driver ODBC driver Middleware Other DB Z39.50 Distributed ADLs Basic collections: catalog, gazetteer Melvyl

15. Development in progress zProblem: incoming metadata must be mapped to FGDC and/or USMARC metadata standards yCurrent catalog schema explicitly implements FGDC and USMARC; has ~80 tables zIngest is inordinately difficult zReport creation is slow

16. Development in progress zSolution: use minimal, bucket-oriented schema that is independent of metadata content standards zSolution: pre-compute the reports Operations DB Maintenance DB Metadata reports (XML) Access reports (XML) Bucket-oriented schema Indexed Standards-based or ad hoc schema One database per dataset Non-indexed Automatic update “Raw” data

17. Summary zADL: a digital library for georeferenced information with user and programmatic interfaces zOffers uniform access to heterogeneous collections zTransitioning from research prototype to operational system zActively ingesting new material zMore portable system is under development