NSDL Data Repository
(NDR)
A lens on STEM Resources
Carl Lagoze
Cornell Information Science
NSDL Pathways Meeting
August 18-19, 2005
Digital Libraries:
Beyond Search and Access
Build on more automated mechanisms for collection
building
Add value to underlying resources via:






Content aggregation: combining information entities in novel
ways
Knowledge integration: capturing semantic relationships
between information entities
Information reuse: allowing secondary, tertiary products
Information transformation: combining information entities with
computational services
collaboration and contribution: blurring the line between authors,
publishers, users, experts…
Resource persistence: providing seamless access to resources
as they change over time.
From Collecting STEM Resources…
…to creating a STEM Web
Evolving the role of NSDL
Phase I – Digital Library Foundation

Collecting, indexing, and providing access to
quality STEM resources from the Web
Phase II – Adding value

Collecting and exploiting contextual
information about STEM resources
NSDL Phase I – Collection Building
Phase I Metadata-Centric Approach
Services
OAI-PMH
Users
Metadata
repository
OAI-PMH
Collections
The metadata repository
is a resource for service
providers.
It holds information
about every collection
and item known to the
NSDL.
Characteristics of the Metadata
Repository
Oracle database
Qualified Dublin Core
Item records with collection association
OAI-PMH ingest and exposure
Current collection ~ 800,000
Metadata quality issues
Problems in this approach
Mere access does not equate to value

Reeves Impact of Media and Technology in Schools
Static metadata records don’t capture
changing and multiple contexts of use and
applicability

Recker and Wiley Designing Instruction with Learning
Objects
Patterns of use, informal opinions,
descriptions often more useful than
taxonomic classification.

Collis and Strijker Technology and Human Issues in
Reusing Learning
Phase II Motivation
Represent (directly or by reference)
multiple entities,




standards
taxonomies
agents (user profiles and roles)
curricula
that are contributed by multiple parties,


users as actors
reuse of primary resources for secondary, tertiary produces
that are inter-related to express context,



applicability to standards
usage in curricula
usage patterns by particular groups/people
and can be integrated with active services
…Towards a collaborative
information environment
Consumers
Valueadded
Information
…adding value to core resources
NDR: A value-added lens over
STEM resources
Contextualization,
Reuse,
Aggregation,
Persistence
Information Foundation
NSDL Data Repository (NDR)
Networked STEM Resources
Some use cases
Multi-sourced rich metadata (beyond DC)

Provenance issues
Annotations, comments, usage scenarios

Quality control
Relations to state standards, curricula

Strand maps
Curricula, lesson plans

Instructional architect, VUE
Information Network Overlay
Client Layer
Network API
Base Web Graph
Network
Representation
Layer
NSDL Selections
Descriptive Metadata
Annotations
Branding
Collection (Semantic)
People and Organizations
Equivalence
Source Layer
Document
Repositories
Data
Stores
Publisher
Repositories
Web
Resources
Databases
Translate to Technical Requirements
Rich information objects

Integration of local and remote mixed-genre content
Dynamic information objects

Integration with local and distributed services
Graph-based information model


Nodes are information objects
Edges are relationships among those objects
Access and management API

exposing full functionality for programmatic access
Fine granularity access management
Fedora Basics
http://www.fedora.info
Open source digital repository software
Collaboration between Cornell University
and University of Virginia
Mellon funding through 2007
International user community
Fedora as the basis for NDR
Aggregate local and remote resources
Web services association for information
reuse/refactoring
Versioning
Ontology-based relationships
API to all functionality
NSDL Fedora Architecture
Fedora API
NSDL Content Model API
Metadata
Ingest
Manager
NSDL Services
NSDL Services
Fedora
Repository
Fedora OAI Service
Repository
Manager
NSDL Services
Resource
Index
NSDL Services
NSDL Services
NSDL Services
Deployment Plans
Production release Phase 1 – 3rd quarter
2005

black box replacement for metadata
repository
Future releases


API available at public level
Relationship building
Applications (1)
Multiple metadata formats



Dublin Core as basic interoperability base
Harvest richer metadata when available
Multiple sourced metadata, provenance
Applications (2)
Stable Identity for STEM Resources






Handles (http://handle.net) for NSDL
resources
Access through NSDL lens (value-added
wrapper)
Stable citation
NSDL branding
Trackability, personalization
Anchor for resource persistence
Applications (3)
NSDL Blog Space


Transitioning AskNSDL to a more interactive
format
Basis for resource contextualization
Annotations
Recommendations
Aggregations
Applications (4)
Instructional Architect (http://ia.usu.edu/)


Aggregate and annotate networked resources
for education use
Capture IA-based teacher contributions in
NDR for use by other teachers/students
Applications (5)
NSDL OnRamp



Open source application for creating content
and managing its workflow
Built on Fedora foundation
Basis for contributions by NSDL community
Applications (6)
Standards alignment and congruence


Leverage Jess & Co work on standards
naming
Link resources to standards and standards to
each other
Some open questions
Scalability of this model
Management
Control – trusted actors
Cross-ontology relationships
Exposing to the user - visualization
Concluding Goals
Exploit the increasing ubiquity of digital
content
Provide the architecture for adding value
to underlying content



Aggregation
Reuse
Integration with computational services
Questions
lagoze@cs.cornell.edu