| Basic Dublin Core Semantics DC 2006 Tutorial 1, 3 October 2006 : Basic Dublin Core Semantics DC 2006 Tutorial 1, 3 October 2006 Marty Kurth
Head of Metadata Services
Cornell University Library |
| Getting started : Getting started Let’s introduce ourselves
Let’s discuss our expectations for the tutorial |
| We’ll cover : We’ll cover An introduction to metadata
Key features of the Dublin Core
Dublin Core metadata in a broader context
Important aspects of the DCMI community |
| An introduction to metadata : An introduction to metadata |
| What is metadata? : What is metadata? A (hopefully) straightforward place to start:
Metadata consists of statements we make about resources to help us find, identify, use, manage, evaluate, and preserve them. |
| Some typical metadata functions : Some typical metadata functions |
| Metadata building blocks (in words) : Metadata building blocks (in words) The basic unit of metadata is a statement.
A statement consists of a property (aka, element) and a value.
Metadata statements describe resources. |
| Metadata building blocks (in pictures) : Metadata building blocks (in pictures) (An oversimplification of the DCMI abstract model for resources!) |
| What are the properties and values in these metadata statements? : What are the properties and values in these metadata statements?
245 00 $a Amores perros $h [videorecording]
Nueve reinas
MovingImage |
| Who cares about metadata? : Who cares about metadata? The term “metadata” has meaning in contexts such as:
Data modeling
Library cataloging
Internet/World Wide Web resource discovery
Led to a convergence between the first two
Formed the context in which Dublin Core arose |
| Key features of the Dublin Core : Key features of the Dublin Core |
| How and why did the Dublin Core come to be in 1995? : How and why did the Dublin Core come to be in 1995? Dramatic increase in the number of document-like resources on the net
Slow improvement in indexing services made resources hard to discover
Belief that descriptive metadata would improve discovery
Perceived need for a descriptive standard that was simple to apply (by non-professionals) |
| Dublin Core Metadata Element Set : Dublin Core Metadata Element Set |
| Characteristics of the Dublin Core : Characteristics of the Dublin Core A flat element structure, with:
All elements optional
All elements repeatable
Elements displayed in any order
Extensible (elements, qualifiers)
Syntax independent
International
Subject independent |
| Resources for which DC is often used : Resources for which DC is often used DCMI Type Vocabulary |
| Dublin Core principles : Dublin Core principles Dumb-down
The one-to-one principle
Appropriate values |
| Dumb-down : Dumb-down Simple DC does not use element refinements or encoding schemes and statements only contain value strings
Qualified DC uses features of the DCMI Abstract Model, particularly element refinements and encoding schemes
Dumbing-down is translating qualified DC to simple DC (property dumb-down and value dumb-down)
For more info, see the DCMI Abstract Model! |
| Element refinements : Element refinements Element refinements narrow the meaning of DC elements
hasVersion and isVersionof refine relation
bibliographicCitation refines identifier
Element refinements are properties, so we typically render them independently
Nine queens
2000-07-11
For more information on rendering DC terms, attend the Basic Syntax Tutorial! |
| Encoding schemes : Encoding schemes Vocabulary encoding schemes
Indicate that a value comes from a controlled vocabulary (e.g., that “Spanish American literature” is an LCSH term)
Syntax encoding schemes
Indicate that a string is formatted in a standard way (e.g., that “1956-11-12” follows ISO 8601)
DCMI recommends using encoding schemes with coverage, date, format, language, subject, and type
For more information on rendering encoding schemes, attend the Basic Syntax Tutorial! |
| The one-to-one principle : The one-to-one principle Create one metadata description for one and only one resource
E.g., do not describe a digital image of the Mona Lisa as if it were the original painting
Group related descriptions into description sets
I.e., describe an artist and his/her work separately, not in a single description |
| Appropriate values : Appropriate values Use elements and qualifiers to meet the needs of your local context, but . . .
Remember that your metadata may be interpreted by machines and people, so . . .
Consider whether the values you use will aid discovery outside your local context and . . .
Make decisions about your local practices accordingly |
| Origins of the DCMI Abstract Model : Origins of the DCMI Abstract Model DC community realized early that machine-processing requires a coherent data model
(1996) “Warwick Framework” proposed at DC-2: Saw DC as one “metadata package” among others
(1997) Qualifiers proposed for specifying meanings
(1998) DCMI functional requirements inform W3C Resource Description Framework (RDF) and RDF informs early Dublin Core data model
(2000) First set of qualifiers officially approved |
| DCMI Abstract Model (2005) : DCMI Abstract Model (2005) Defines resources in terms of semantic relationships among classes, properties, and values
Defines a model for DCMI descriptions, description sets, and records
Serves as a foundation for future DCMI developments
Serves as a conceptual model for metadata initiatives outside DCMI |
| DCMI namespaces and policies : DCMI namespaces and policies All DCMI terms have unique identity within three namespaces:
http://purl.org/dc/elements/1.1/ - DCMES (15 elements)
http://purl.org/dc/terms/ - DCMI elements and qualifiers
http://purl.org/dc/dcmitype/ - DCMI Type Vocabulary
DCMI namespace policies promote long-term stability of namespace URIs
Only substantial semantic changes will result in change of namespace URIs |
| Dublin Core metadata in a broader context : Dublin Core metadata in a broader context |
| Metadata creation and distribution models : Metadata creation and distribution models Federation
Extensive specifications, standards, protocols, training
Harvesting
Basic agreements, reliance on best practices
Gathering
Automated indexing of content, algorithms yield results from search terms, less likely to use descriptive metadata per se |
| Harvesting model key features : Harvesting model key features Integrating metadata from many sources calls for common element sets, record structures, and harvesting protocols
Open Archives Initiative Protocol for Metadata Harvesting serves as a framework for sharing metadata and mandates ‘simple DC’ as a common metadata format
Harvesting promotes metadata reuse
Best practices balance cost and interoperability
Communities add value to basic infrastructure (more complex metadata, new uses for protocol) |
| Application profiles & interoperability : Application profiles & interoperability Application profiles enable:
Implementers to use DC metadata in conjunction with non-DC metadata
Implementers to benefit from the experience of their peers
Communities to harmonize metadata usage for greater interoperability
For more information on application profiles, attend the Application Profiles Tutorial! |
| Important aspects of the DCMI community : Important aspects of the DCMI community |
| Dublin Core grows and changes : Dublin Core grows and changes DCMI emphasizes open participation
Conferences, working groups, discussion lists
DCMI term set evolves as implementers coin new terms and usage patterns emerge
DCMI Usage Board reviews proposals for new metadata terms |
| Dublin Core Usage Board : Dublin Core Usage Board Considers proposals for new terms (elements, refinements, encoding schemes, DCMI Type Vocabulary terms)
Evaluates proposals in light of grammatical principle, semantic clarity, usefulness, and overlap with existing terms
Evaluates constructs that use DCMI terms, such as application profiles |
| Find out more about DC : Find out more about DC DCMI Web Site
http://dublincore.org
Using Dublin Core
http://dublincore.org//documents/usageguide/
DCMI Abstract Model
http://dublincore.org/documents/abstract-model/
DCMI Working Groups
http://dublincore.org/groups
AskDCMI
http://askdcmi.askvrd.org/ |
| Questions? : Questions?
Or please send questions to:
Marty Kurth
Cornell University Library
mk168@cornell.edu |
| Acknowledgement : Acknowledgement Many thanks to Diane Hillmann for sharing the slides from an earlier version of this tutorial with me. |
| Interested in DC origins and history? : Interested in DC origins and history? Lagoze, Carl. “The Warwick Framework: A Container Architecture for Diverse Sets of Metadata.” D-Lib Magazine July/August 1996.
Miller, Eric J. “An Overview of the Dublin Core Data Model.” 6 June 1999.
Weibel, Stuart. “Metadata: The foundations of resource description.” D-Lib Magazine July 1995.
Weibel, Stuart L, and Carl Lagoze. “An element set to support resource discovery: The state of the Dublin Core: January 1997.” International Journal on Digital Libraries 1 (1997): 176-86. |