DATE PREPARED: 15 February, 1997.
ORGANIZATION: University of California at Santa Barbara.
PRINCIPAL INVESTIGATORS:
Terence R. Smith
Department of Computer Science
University of California at Santa Barbara
Santa Barbara
CA 93106.
smithtr@cs.ucsb.edu
805-893-2966
805-893-8553 (FAX)
Michael F. Goodchild,
Department of Geography
University of California at Santa Barbara
Santa Barbara
CA 93106.
good@geog.ucsb.edu
805-893-8049
805-893-8553 (FAX)
TITLE OF EFFORT:
ALEXANDRIA: A DIGITAL LIBRARY FOR GEOGRAPHICALLY-REFERENCED MATERIALS
ACCESS INFORMATION:
http://alexandria.sdc.ucsb.edu
OBJECTIVE:
The goal of the Alexandria Project
is to build a distributed digital library (DL)
that allows users to access and manipulate information
in a variety of classes of collection items in terms of
geospatial reference.
A central function of ADL is to
provide users with access to the information in
a large range of digital materials-ranging from maps and images
to text to multimedia-in terms of geographical reference.
An important type of query is ``What information
is there in the library about some phenomenon at
a particular set of places?''.
From the Internet, both users and librarians can access
various components of ADL, such as its
catalog and collections, through powerful, graphical
interfaces without having to know where
these different components are located on the Internet.
APPROACH:
The main aspect of ADL's strategic approach involves:
(1) a focus upon access to the information contained
in many classes of collection items,
including non-traditional items,
by geographical reference;
(2) the development of the user interface (UI)
and catalog components of the DL architecture;
(3) accessibility to the ADL catalog and collections
via the Internet for a wide variety of users;
(4) close interaction and interoperability with other DL activities
by way of Internet-related technologies;
(5) a process of incremental, evolutionary design and implementation of ADL
that takes advantage of critical technological developments
and especially Internet-related technologies;
(6) digitally-supportable extensions to traditional library functionality.
In particular, the transitions from our initial stand-alone
rapid prototype (RP) in early 1995,
to our first World Wide Web prototype (WP) in late 1995,
to our publicly-available testbed in early-1997,
to our million-item operational library in mid-1998,
are being made in incremental steps that build upon each other
and upon a basic four-component architecture.
This architecture involves: (1) user interface components that support
graphic and text-based access to the other ADL
components and services; (2) a distributed catalog component
with metadata and search engines permitting
users to identify holdings of interest; (3) a distributed storage component
containing the digital holdings; and (4)
an ingest component allowing librarians to
store new holdings, extract metadata from the holdings,
and add metadata to the catalog.
A variety of technologies being applied and developed
in each of the four components. The graphical/geographical
interface is supported by a variety of internet-related
technologies, such as browsers and programmable browsers.
Access to the holdings is by way of a catalog component
that supports spatially-based
metadata models and content-based search techniques.
Currently such techniques employ gazetteers for map
documents and texture features for image documents.
Browsing and the delivery of large items is supported
by progressive delivery techniques based on wavelet
technology. The high-performance servers that support
the library operation are being based in part on approaches
that involve parallel computing.
PROGRESS:
The main thrust of our implementation effort is to
develop a quasi-operational testbed system.
Our progress to date toward this goal can be summarized as:
* 1994 (6 months): stand-alone ``Rapid Prototype'';
* 1995: Web Prototype: initial deployment;
* 1996: Web Prototype: expansion and evaluation.
Much of 1996 was devoted to issues of depth rather than breadth.
While no radically new functionality was added to the Web Prototype,
many existing capabilities were fleshed out, and the collections
to which the Web Prototype provides access were significantly
extended. Moreover, we made a concerted effort to synthesize
and evaluate feedback from the Web Prototype's
user community, which grew to more than 2,000 during 1996.
This feedback continues to provide vital input to:
* the look and feel of the Testbed's next user interface;
* the necessary scope and depth of ADL's new collections;
* identifying bottlenecks in the overall system's response that are
particularly onerous to Testbed users.
The Testbed's infrastructure was significantly augmented in 1996, with
the installation of a 300 GB server and a fiber-optic connection to the
UCSB backbone network. Taking advantage of this increased capacity, the
Testbed now supports multiple catalog database systems, multiple map
renderers for the user interface, and a catalog and gazetteer that have
each increased in size by more than an order of magnitude.
RECENT ACCOMPLISHMENTS
First remote testbed installation at San Diego Supercomputer Center
copy of Testbed catalog node (database server, Web middleware)
primary backup for the ADL catalog
containing additional SDSC-specific collections
Metadata ingest over the Web
allows any user with a Web browser to enter object
into the ADL catalog
Large catalog and gazetteer loaded
- 500 K catalog records
- 5.9 M gazetteer records
Testbed support for multiple database systems
Illustra on SPARC/Solaris
Oracle on Alpha/Digital UNIX
Testbed support for multiple map renderers
Xerox PARC MapBrowser
ESRI MapObjects
PLANS:
Making testbed accessible to anyone from the WWW,
available by early-1997 and providing access
to significant collections.
Completing redesign and implementation
of user interface and integration
of a digital atlas in support of spatial browsing.
Extending ADL into a truly distributed digital library
with several sites.
Integration into testbed of scalable
Web server/client technology.
Loading of approximately 100GB of geospatially
indexed information as initial collection
having value to users from
targeted user groups.
Extending metadatabase of ADL with
expanded metadata models, spatial information
mined from on-line catalogs,
and iconic thesaurus based on concept space approach.
Extending spatial search capabilities of ADL
with variety of technologies, including ESRI/Oracle
software and BANG indexing.
Incorporation into testbed of wavelet-based progressive delivery
of images, progressive subregion retrieval,
content-based search of images,
Re-design and re-implementation of system in
terms of distributed object technology in
support of view of ADL as set of distributed
library services that can be integrated by user.
TECHNOLOGY TRANSITION, SHARING, AND PARTNERING:
We are working closely with a broad range of
partners in testing and applying their technologies
and in sharing our technologies and research results.
For example, we are characterizing the behavior of large databases
in a new DEC hardware environment provided in part by
DEC and the US Navy (NAVO, Stennis);
we are examining the applicability of ESRI's MapObjects
as the basis for a map browser;
with Hughes, we are developing a gazetteer that will be of
use for EOS-DIS; we are partnering with Microsoft
in the development of a 1TB online, Web-accessible database system;
we are working with NASA on the development of gazetteer
content standards;
we are prototyping distributed image access
services based on the Common Object
Request Broker Architecture (CORBA)
in conjunction with NIMA;
we are applying and evaluating a variety
of Oracle software packages, including
relational and ``object oriented'' database software;
we are partnering with SDSC in building a clone of
ADL at SDSC; we are working with USGS
on a variety of data and metadata issues;
and we are working closely with the
US Navy (NRaD at San Diego in building
high-performance Web servers.
We are also making versions of our testbed
available to our partners.