Dublin Core Metadata Initiative

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Dublin Core Metadata Initiative

• Evangelos Milios

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Metadata

• Structured data about data
• Electronic data
• Physical objects (e.g. museum items)
• Generated
• By hand
• Automatically
• Stored
• As separate record from the resource
• Embedded in the resource itself
• Aim
• Facilitate management and resource discovery
• Like Library Catalog Cards describing books for
  retrieving them

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DCMI

• Dublin Core Metadata Initiative
• Organization fostering adoption of metadata
  standards and vocabularies for describing
  resources.
• Core foundation of property types and values
  about Web resources

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Goals of DC

• Simplicity of creation and maintenance
• Simple enough for non-specialist
• To create descriptive records of resources
• Commonly understood semantics
• Across fields
• Internationalization (versions in languages other
  than English)
• Extensibility
• Domain-specific metadata sets

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Dublin Core Metadata Element Set (DCMES)

• Semantic vocabulary for describing the core
  information properties
• Useful across a broad range of industries and
  disciplines
• Elements such as title, creator, subject,
  publisher, etc.
• Dublin Core based projects

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Simple vs. Qualified Dublin Core

• Simple only the main 15 elements of DCMES are
  used as attribute-value pairs.
• Values strings
• Qualified additional qualifiers
• Values strings or structured values
• Increased specificity
• Additional complexity
• Risk of incompatibilities if not standard
• Qualified HTML Examples

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Dublin Core Metadata use

• DC metadata is storedin HTML files using META
  tags, or in databases.
• University of Washington Digital Collections
• Uses extended Dublin Core descriptors for image
  and text collections
• http//content.lib.washington.edu/aipnw/
• Texts Metadata in HTML files (example)
• Images Metadata in DB (example)

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Relation of DC with RDF and XML

• DC co-evolved with RDF
• DC provided the motivation for RDF
• RDF is a formal data model for the DC community

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Dublin Core data model

• The 15 elements
• Relationships of current resource with other
  resources of any type, with their own DCMES
  description e.g.
• Creator relate to its creator
• Coverage relate to place or time-period
• Value recorded is the URI of that resource

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Search engines and DC

• Meta information used for spamming!
• Standard search engines do not use DC
• Metadata Services and Tools