Dublin Core, the DCMI Abstract Model & DC Application Profiles Images DC Application Profile WG meeting, London

Dublin Core, the DCMI Abstract Model & DC Application Profiles Title slide photo of Banksy painting by Flickr user s0mmie See http://www.flickr.com/photos/s0mmie/459881039/ / Made available under CC Attribution- NonCommercial -Share-Alike 2.0 license

Title slide photo of Banksy painting by Flickr user s0mmie See http://www.flickr.com/photos/s0mmie/459881039/ / Made available under CC Attribution- NonCommercial -Share-Alike 2.0 license

An Introduction to the DCMI Abstract Model Why the DCAM? The DCMI Abstract Model The DCAM & “DC application profiles” Dublin Core in 2007

Why the DCAM?

The DCMI Abstract Model

The DCAM & “DC application profiles”

Dublin Core in 2007

Why DCAM? Context & Motivation Some issues for DCMI c.2003 Metadata vocabularies … but what is a DC “element”? Encoding guidelines … but what are we “encoding”? DC application profiles … but what “terms” can we “use”? “ Simple” and “Qualified” DC Grammatical Principles DC & the Resource Description Framework Work on DCAM from mid-2003, initiated by Andy Powell Initial Version, DCMI Recommendation, 2005-03-07 Second Version, DCMI Recommendation, 2007-06-04 http://dublincore.org/documents/2007/06/04/abstract-model/

Some issues for DCMI c.2003

Metadata vocabularies

… but what is a DC “element”?

Encoding guidelines

… but what are we “encoding”?

DC application profiles

… but what “terms” can we “use”?

“ Simple” and “Qualified” DC

Grammatical Principles

DC & the Resource Description Framework

Work on DCAM from mid-2003, initiated by Andy Powell

Initial Version, DCMI Recommendation, 2005-03-07

Second Version, DCMI Recommendation, 2007-06-04

http://dublincore.org/documents/2007/06/04/abstract-model/

The DCMI Abstract Model

The DCMI Abstract Model DCAM concerned with description of resources DCAM adopts Web Architecture/RFC3986 definition of resource the term "resource" is used in a general sense for whatever might be identified by a URI. Familiar examples include an electronic document, an image, a source of information with consistent purpose (e.g., "today's weather report for Los Angeles"), a service (e.g., an HTTP to SMS gateway), a collection of other resources, and so on. A resource is not necessarily accessible via the Internet; e.g., human beings, corporations, and bound books in a library can also be resources. Likewise, abstract concepts can be resources, such as the operators and operands of a mathematical equation, the types of a relationship (e.g., "parent" or "employee"), or numeric values (e.g., zero, one, and infinity). RFC3986 URI Syntax

DCAM concerned with description of resources

DCAM adopts Web Architecture/RFC3986 definition of resource

the term "resource" is used in a general sense for whatever might be identified by a URI. Familiar examples include an electronic document, an image, a source of information with consistent purpose (e.g., "today's weather report for Los Angeles"), a service (e.g., an HTTP to SMS gateway), a collection of other resources, and so on.

A resource is not necessarily accessible via the Internet; e.g., human beings, corporations, and bound books in a library can also be resources.

Likewise, abstract concepts can be resources, such as the operators and operands of a mathematical equation, the types of a relationship (e.g., "parent" or "employee"), or numeric values (e.g., zero, one, and infinity).

RFC3986 URI Syntax

The DCMI Abstract Model DCAM describes Components and constructs that make up an information structure (“DC description set”) How that information structure is to be interpreted Made up of three related “information models” Resource model Description set model Vocabulary model In this presentation, focus on description set model

DCAM describes

Components and constructs that make up an information structure (“DC description set”)

How that information structure is to be interpreted

Made up of three related “information models”

Resource model

Description set model

Vocabulary model

In this presentation, focus on description set model

The DCMI Abstract Model DCAM does not describe how to represent DC description set in concrete form “ Encoding guidelines” Updating of specs in progress (2007) DC-XML DC in X/HTML link/meta elements Some formats defined outside of DCMI, e.g. Eprints DC-XML DCAM describes various types of metadata term, but does not specify the use of any fixed set of terms Metadata vocabularies Define/owned by DCMI or by other agencies DCAM & RDF Mapping of description sets to RDF graph specified by Expressing DC metadata using RDF http://dublincore.org/documents/2007/06/04/dc-rdf

DCAM does not describe how to represent DC description set in concrete form

“ Encoding guidelines”

Updating of specs in progress (2007)

DC-XML

DC in X/HTML link/meta elements

Some formats defined outside of DCMI, e.g. Eprints DC-XML

DCAM describes various types of metadata term, but does not specify the use of any fixed set of terms

Metadata vocabularies

Define/owned by DCMI or by other agencies

DCAM & RDF

Mapping of description sets to RDF graph specified by Expressing DC metadata using RDF http://dublincore.org/documents/2007/06/04/dc-rdf

DCAM Resource Model

DCAM Resource Model The “view of the world” on which DC metadata is based a described resource is described using one or more property-value pairs a property-value pair is made up of exactly one property and exactly one value a value is a resource a value is either a literal value or a non-literal value i.e. similar to RDF model of binary relations between resources; entity-relational model

The “view of the world” on which DC metadata is based

a described resource is described using one or more property-value pairs

a property-value pair is made up of

exactly one property and

exactly one value

a value is a resource

a value is either a literal value or a non-literal value

i.e. similar to RDF model of binary relations between resources; entity-relational model

DCAM Description Set Model

DCAM Description Set Model The structure of DC metadata Uses URIs to refer to resources & metadata terms (like RDF) a description set is made up of one or more descriptions , each of which describes one resource a description is made up of zero or one described resource URI identifies described resource one or more statements a statement is made up of exactly one property URI identifies property exactly one value surrogate a value surrogate is either a literal value surrogate or a non-literal value surrogate

The structure of DC metadata

Uses URIs to refer to resources & metadata terms (like RDF)

a description set is made up of one or more descriptions , each of which describes one resource

a description is made up of

zero or one described resource URI

identifies described resource

one or more statements

a statement is made up of

exactly one property URI

identifies property

exactly one value surrogate

a value surrogate is either a literal value surrogate or a non-literal value surrogate

Resource URI Resource URI Description Set Description Statement Property URI Literal Value Surrogate Description Statement Property URI Non-Literal Value Surrogate Statement Property URI Non-Literal Value Surrogate

DCAM Description Set Model a literal value surrogate is made up of exactly one value string encodes value a non-literal value surrogate is made up of zero or one value URIs identifies value zero or one vocabulary encoding scheme URI identifies a set of which the value is a member zero or more value strings represents value a value string is either a plain value string or a typed value string a plain value string may have an associated value string language a typed value string is associated with a syntax encoding scheme URI

a literal value surrogate is made up of

exactly one value string

encodes value

a non-literal value surrogate is made up of

zero or one value URIs

identifies value

zero or one vocabulary encoding scheme URI

identifies a set of which the value is a member

zero or more value strings

represents value

a value string is either a plain value string or a typed value string

a plain value string may have an associated value string language

a typed value string is associated with a syntax encoding scheme URI

Value URI Description Set Description Statement Property URI Resource URI Literal Value Surrogate Description Statement Property URI Resource URI Non-Literal Value Surrogate Statement Property URI Non-Literal Value Surrogate Vocab Enc Scheme URI Value URI Value string Value string Syntax Enc Scheme URI Language Value string Language

DCAM Description Set Model a value may be described by another description

a value may be described by another description

Description Set Description Statement Property URI Resource URI Literal Value Surrogate Description Statement Property URI Resource URI Non-Literal Value Surrogate Statement Property URI Non-Literal Value Surrogate Value URI Vocab Enc Scheme URI Value URI Value string Value string Value string Syntax Enc Scheme URI Language Language

Description Set Description Statement Property URI Literal Value Surrogate Description Statement Property URI Resource URI Non-Literal Value Surrogate Statement Property URI Non-Literal Value Surrogate Vocab Enc Scheme URI Value URI Value string Value string Value string Syntax Enc Scheme URI Language Language

Description Set Description Property URI Resource URI Example: Description set with two descriptions, statements with non-literal value surrogates & literal value surrogates Statement Property URI Non-Literal Value Surrogate Non-Literal Value Surrogate Vocab Enc Scheme URI Value URI Value string Value string Value URI Language Language Description Resource URI Property URI Literal Value Surrogate Value string Language Statement Statement

Description Set Description Statement <http:/purl.org/dc/terms/subject> Non-Literal Value Surrogate Non-Literal Value Surrogate <http://example.org/terms/mySH> “ Metadata” &quot;Métadonnées&quot; en fr <http://purl.org/dc/terms/publisher> <http://dublincore.org/documents/abstract-model/> <http://example.org/org/DCMI> Property URI Value URI <http://example.org/org/mySH/h123> Value URI Property URI Vocab Enc Scheme URI Value String Value String Description <http://example.org/org/DCMI> <http://xmlns.com/foaf/ 0.1/name> Literal Value Surrogate “ Dublin Core Metadata Initiative” en Value String Property URI Example: Description set with two descriptions, statements with non-literal value surrogates & literal value surrogates Statement Statement

@prefix dcterms <http://purl.org/dc/terms/> . @prefix foaf <http://xmlns.com/foaf/0.1/> . DescriptionSet ( Description ( ResourceURI ( <http://dublincore.org/documents/abstract-model/> ) Statement ( PropertyURI ( dcterms:publisher ) ValueURI (<http://example.org/org/DCMI> ) ) Statement ( PropertyURI ( dcterms:subject ) ValueURI (<http://example.org/mySH/h123> ) VocabEncSchemeURI (<http://example.org/terms/mySH> ) ValueString ( “Metadata” Language (en ) ) ValueString ( &quot;Métadonnées&quot; Language (fr ) ) ) ) Description ( ResourceURI ( <http://example.org/org/DCMI> ) Statement ( PropertyURI ( foaf:name ) LiteralValueString ( “Dublin Core Metadata Initiative” Language (en) ) ) ) )

The DCAM & “DC application profiles”

The DCAM & “DC application profiles” DCAM does not specify the set of terms referenced in a description set Notion of “DC application profile” widely used within DCMI and by DC implementers Typically annotated lists of terms used in DC metadata so as to meet some domain/community requirements Terms defined by DCMI or by other agencies Specification of how to construct description sets (descriptions, statements) to serve some purpose Based on functional requirements domain model

DCAM does not specify the set of terms referenced in a description set

Notion of “DC application profile” widely used within DCMI and by DC implementers

Typically annotated lists of terms used in DC metadata so as to meet some domain/community requirements

Terms defined by DCMI or by other agencies

Specification of how to construct description sets (descriptions, statements) to serve some purpose

Based on

functional requirements

domain model

DCMI Description Set Profile (DSP) A way of describing structural constraints on a description set the resources that may be described by descriptions in the description set the properties that may be used in statements the ways a value surrogate may be given Description templates, statement templates Model & XML Syntax for DSP Working draft by Mikael Nilsson ( Royal Institute of Technology, Sweden) http://dublincore.org/architecturewiki/DescriptionSetProfile Wiki Syntax for DSP Working draft by Fredrik Enoksson ( Royal Institute of Technology, Sweden) http:// dublincore.org/architecturewiki/DSPWikiSyntax

A way of describing structural constraints on a description set

the resources that may be described by descriptions in the description set

the properties that may be used in statements

the ways a value surrogate may be given

Description templates, statement templates

Model & XML Syntax for DSP

Working draft by Mikael Nilsson ( Royal Institute of Technology, Sweden)

http://dublincore.org/architecturewiki/DescriptionSetProfile

Wiki Syntax for DSP

Working draft by Fredrik Enoksson ( Royal Institute of Technology, Sweden)

http:// dublincore.org/architecturewiki/DSPWikiSyntax

What is a DC Application Profile? A DCAM-conformant Application Profile (“DC Application Profile”) is packet of documentation which consists of: Functional requirements (desirable) Domain model (mandatory) Description Set Profile (DSP) (mandatory) Usage guidelines (optional) Encoding syntax guidelines (optional)

A DCAM-conformant Application Profile (“DC Application Profile”) is packet of documentation which consists of:

Functional requirements (desirable)

Domain model (mandatory)

Description Set Profile (DSP) (mandatory)

Usage guidelines (optional)

Encoding syntax guidelines (optional)

Foundation standards Domain standards Application Profile The “Singapore Framework”

Dublin Core in 2007

Dublin Core in 2007 a framework (the DCAM) which describes how to use certain types of terms ... to make statements ... ... that form descriptions (of resources) … that can be grouped together as description sets a set of specifications for encoding description sets using various formats a managed vocabulary of widely useful terms which can be referenced in statements support for defining additional vocabularies of terms which can be referenced in statements support for defining DC application profiles which describe how to construct description sets for some particular set of requirements extensibility, modularity, compatibility with Semantic Web

a framework (the DCAM)

which describes how to use certain types of terms

... to make statements ...

... that form descriptions (of resources)

… that can be grouped together as description sets

a set of specifications for encoding description sets using various formats

a managed vocabulary of widely useful terms

which can be referenced in statements

support for defining additional vocabularies of terms

which can be referenced in statements

support for defining DC application profiles

which describe how to construct description sets for some particular set of requirements

extensibility, modularity, compatibility with Semantic Web

Dublin Core, the DCMI Abstract Model & DC Application Profiles Images DC Application Profile WG meeting, London