Home

Chapter 2. Understanding Metadata Vocabularies

Chapter 2 section titles

2.1 Metadata Element Sets
2.1.1 Components and Structures – An Overview
2.1.2 Flat Structure
2.1.2.1 Dublin Core Metadata Element Set
2.1.2.2 VRA Core 3.0
2.1.3 Nested Structure
2.1.3.1 VRA Core 4.0
2.2 Application Profiles
2.2.1 The Concept of Application Profile
2.2.2 Examples of APs Consisting of Elements Drawn from Other Schemas
2.2.3 Sources of Reusable Elements
2.3 Ontologies as Metadata Vocabularies
2.3.1 Background
2.3.2 Modular Structure
2.3.3 Friend of a Friend (FOAF)
2.3.4 Schema.org
2.4. RDF Vocabularies for Metadata Terms
2.4.1 An Introduction to RDF (Resource Description Framework)
2.4.2 DCMI Metadata Terms
2.4.3 Metadata Descriptions: From “Records” to “Statements”

Links to sources

The star* = newly updated* or added**

Figure 2-1-1 An entry for DC element date ..... 39

Figure 2-1-2 An entry for VRA Core 4 element title ..... 40

Figure 2-1-3 The 15 Dublin Core elements seen from three categories, composite based on DCMES, Version 1.1..... 44

*Figure 2-1-5 VRA Core 4.0 elements and sub-elements, composite based on VRA Core 4.0 Element Outline 2007 (pdf)..... 52

Figure 2-2-2 AVEL metadata element list..... 56
(Was at https://avel.library.uq.edu.au/technical.html; no longer available.)

Figure 2-2-3 Portion of the metadata elements within the NSDL_DC metadata framework, from NSDL_DC Metadata Guidelines Part V.1. ..... 57

Figure 2-3-1 The Semantic Web Layer Cake: Tim Berners-Lee. 2000 . and W3C Latest layer cake diagram..... 60

Figure 2-3-2 A FOAF file for a Person instance ..... 63

*Figure 2-3-3 Explanation of the Schema.org Type Hierarchy view and Individual Type view of "Book" type ..... 65

*Figure 2-4-5 RDF serialization formats at a glance, generated based on "What's New in RDF 1.1"..... 71

*Figure 2-4-6 dcterms:creator ..... 73

Figure 2-4-8 dcterms:accrualPeriodicity's domain and range ..... 76

Exercises

For each section, read documents provided by the owners of the metadata standards (e.g., DCMES, VRA Core 4.0, Schema.org, and DC Terms) concentrating primarily on the specifications of each element set and its user guide. Exclude XML schemas prepared for machine processing.

See also exercises for textbook 1st edition, index.html

For example:

Readings

Baker, Thomas. 2012. "Libraries, Languages of Description, and Linked Data: A Dublin Core Perspective." Library Hi Tech 30 (1):116−33.

Harper, Corey. 2010. "Dublin Core Metadata Initiative: Beyond the Element Set." Information Standards Quarterly 22 (1):21−28. http://www.niso.org/publications/isq/free/FE_DCMI_Harper_isqv22no1.pdf.

Heery, Rachel, and Manjula Patel. 2000. "Application Profiles: Mixing and Matching Metadata Schemas." Ariadne, no. 25. http://www.ariadne.ac.uk/issue25/app-profiles/.

Manola, Frank, Eric Miller, and Brian McBride. 2014. "RDF 1.1 Primer." W3C Working Group Note 25, February 2014. http://www.w3.org/TR/rdf11-primer/.

Takeaways

1. In an element set, each element should have
at least these basic components:
element ID, name, label,
definition,
comment (best practices and data value restriction),
and reference.

 

2. Creators of metadata specifications must make decisions on:
- Elements and their structures (relationships between elements)
- Constraints on elements AND content.

Elements in a metadata standard can be organized
in a flat, nested, or modular style.

 

3. In an Application Profile (AP), the elements may be from one or more element sets, thus allowing a given application to meet specialized and/or local functional requirements.

- Consider reuse of elements in existing standards to avoid reinventing the wheel.


4. There are metadata vocabularies that
are self-described as
- ontologies,
- schemas, and
- RDF vocabularies.

They are encoded with OWL (Web Ontology Language) and RDF serialization formats.