Networked Knowledge Organization Systems
Dublin Core Application Profile
(NKOS AP)

http://w3id.org/nkos
Title
Networked Knowledge Organization Systems Dublin Core Application Profile (NKOS AP)
Description
This file specifies the set of RDF classes and properties used in NKOS AP.
Creator
Contributor
Described by
Date Created
2014-04-03
Date Modified
2015-10-03; 2019-11-03
Version
0.2

Introduction | NKOS AP at a glance | Re-used Classes | NKOS AP Properties ||Re-used Properties

Section 1. Introduction

Scope

This file specifies the set of RDF classes and properties used in the "Networked Knowledge Organization Systems Dublin Core Application Profile (NKOS AP)". The metadata schema can be used to describe knowledge organization systems/services (KOS) resources, such as thesauri, classification schemes, subject heading systems, taxonomies, and ontologies that are developed for organizing information and promoting knowledge management.[1] The information about a KOS, including its data model, type, protocol, status, responsible body, available format, affectivity, and other descriptive data are very important to terminology registries, service registries, vocabulary users (machine or human), and retrieval systems. At a minimum level, metadata for KOS resources will describe specific characteristics of a KOS, facilitate the discovery of KOS resources, assist in the evaluation of such resources for a particular application or use, and facilitate sharing, reusing, and collaboration of the KOS resources.

This Dublin Core Application Profile for describing KOS resources is developed based on the work the Networked Knowledge Organization Systems (NKOS) community [http://nkos.slis.kent.edu/] has done since 1998.  

[1] For the types of KOS resources, consult NKOS-Types vocabulary.

Namespaces used by this AP

adms http://www.w3.org/ns/adms#
dcat http://www.w3.org/ns/dcat#
dct http://purl.org/dc/terms/
frbrer http://iflastandards.info/ns/fr/frbr/frbrer/
frsad  http://iflastandards.info/ns/fr/frsad/
nkos http://w3id.org/nkos#
prov http://www.w3.org/ns/prov#
wdrs http://www.w3.org/2007/05/powder-s#

NKOS AP at a glance

This section is non-normative.

Classes dct:Agent , dct:AgentClass , adms:Asset , frbrer:Expression , dct:LinguisticSystem , frbrer:Manifestation , dct:MediaTypeOrExtent, dct:RightsStatement , frsad:Thema , frbrer:Work

Properties

-nkos defined:

nkos:alignedWith , nkos:basedOn , nkos:serviceOffered , nkos:sizeNote , nkos:updateFrequency , nkos:usedBy
-reused: dct:audience , dcat:contactPoint , dct:created , dct:creator , wdrs:describedBy , dct:description , dct:format , dct:identifier , frbrer:isEmbodimentOf , dct:isPartOf , frbrer:isRealizationOf , dct:issued , dct:language , dct:modified , dct:publisher , dct:relation , dct:rights , adms:sample , dct:subject , dct: title , dct:type , prov:wasDerivedFrom


Attributes used for each term in this AP:

  • Term name: A token appended to the IRI of a namespace to create the IRI of the term.
  • IRI: The Internationalized Resource Identifier used to uniquely identify a term.
  • Label: The human-readable label assigned to the term.
  • Definition: A statement that represents the concept and essential nature of the term, taken from the original namespace.
  • Comment: Additional information about the term or its application, taken from the original namespace.
  • NKOS Usage Note:Additional information about the term or its application made by this AP, for NKOS use.
  • Has Range: A Class of which a value described by the term is an Instance.[1] Ranges are the objects of the statement (i.e. a subject-predicate-object RDF triple), or the expected value.[2]
  • Expected value: A further explanation of the range of properties such as an IRI/structured entity or literal/typed data.[2]
  • Has Domain: A Class of which a resource described by the term is an Instance.[1] It indicates that a property applies to a particular class.  Domains are the subjects of a statement (i.e. a subject-predicate-object RDF triple).[2]
    [1]According to DCMI Terms http://dublincore.org/documents/dcmi-terms/
    [2]According to BIBFRAME Vocabulary http://www.loc.gov/bibframe/docs/vocab-conventions.html

Section 2. Re-used Classes

Agent
Term Name dct:Agent
IRI http://purl.org/dc/terms/Agent
Label
Agent
Definition
A resource that acts or has the power to act.
Comment
Examples of Agent include person, organization, and software agent.


Agent Class
Term Name dct:AgentClass
IRI http://purl.org/dc/terms/AgentClass/td>
Label
Agent Class
Definition
A group of agents.
Comment
Examples of Agent Class include groups seen as classes, such as students, women, charities, lecturers.


Asset
Term Name adms:Asset
IRI http://www.w3.org/ns/adms#Asset
Label
Asset
Definition
An abstract entity that reflects the intellectual content of the asset and represents those characteristics of the asset that are independent of its physical embodiment.
Comment
Assets can be versioned. Every time the intellectual content of an asset changes, the result is considered to be a new asset that can be linked to previous and next versions of the Asset.
NKOS Usage Note
This abstract entity combines the FRBR entities work (a distinct intellectual or artistic creation) and expression (the intellectual or artistic realization of a work) [ FRBR ].


Expression
Term Name frbrer:Expression
IRI http://iflastandards.info/ns/fr/frbr/frbrer/C1002
Label
Expression
Definition
The intellectual or artistic realization of a work in the form of alpha-numeric, musical, or choreographic notation, sound, image, object, movement, etc., or any combination of such forms.
NKOS Usage Note
A particular version of the KOS, such as in a particular language or an abridgment.


Linguistic System
Term Name dct:LinguisticSystem
IRI http://purl.org/dc/terms/LinguisticSystem
Label
Linguistic System
Definition
A system of signs, symbols, sounds, gestures, or rules used in communication.
Comment
Examples include written, spoken, sign, and computer languages.


Manifestation
Term Name frbrer:Manifestation
IRI http://iflastandards.info/ns/fr/frbr/frbrer/C1003
Label
Manifestation
Definition
The physical embodiment of an expression of a work.
NKOS Usage Note
Examples are: the printed edition of a thesaurus' 2010 English version, the SKOS Linked Data representation of the same version.


Media Type
Term Name dct:MediaTypeOrExtent
IRI http://purl.org/dc/terms/MediaType
Label
Media Type
Definition
A file format or physical medium.


Rights Statement
Term Name dct:RightsStatement
IRI http://purl.org/dc/terms/RightsStatement
Label
Rights Statement
Definition
A statement about the intellectual property rights (IPR) held in or over a Resource, a legal document giving official permission to do something with a resource, or a statement about access rights.


Thema
Term Name frsad:Thema
IRI http://iflastandards.info/ns/fr/frsad/C1001
Label
Thema
Definition
Any entity used as a subject of a work.
NKOS Usage Note
A subject domain to which the KOS belongs. It can be a broad subject or any number of narrower subjects. Suggest to use a controlled vocabulary for those subjects.


Work
Term Name frbrer:Work
IRI http://iflastandards.info/ns/fr/frbr/frbrer/C1001
Label
Work
Definition
A distinct intellectual or artistic creation.
NKOS Usage Note
Usually a KOS as a whole is a work, e.g., ASIS&T Thesaurus.

Section 3. NKOS AP Properties

Aligned with
Term Name fnkos:alignedWith
IRI http://w3id.org/nkos#alignedWith
Label
Aligned With
Definition
A related resource with which the described resource is aligned.
Has Domain
Has Range
Expected value IRI of an expression


Based on
Term Name nkos:basedOn
IRI http://w3id.org/nkos#basedOn
Label
Based On
Definition
A resource used as the source for a derivative resource.
Has Domain
Has Range
Expected value IRI of a work


Service offered
Term Name nkos:serviceOffered
IRI http://w3id.org/nkos#serviceOffered
Label
Service Offered
Definition
Services provided to users for the described resources.
Has Domain
NKOS Usage Note
Example: download, extract, query, annotation.
Has Range
Expected value literal


Size Note
Term Name nkos:sizeNote
IRI http://w3id.org/nkos#sizeNote
Label
Size Note
Definition
Number of concepts, terms, or other semantic units included in a KOS.
Has Domain
Has Range
Expected value literal


Used By
Term Name nkos:usedBy
IRI http://w3id.org/nkos#usedBy
Label
Used By
Definition
Agent using the described KOS.
Has Domain
Has Range Agent Class
Expected value IRI of an agent


Update Frequency
Term Name nkos:updateFrequency
IRI http://w3id.org/nkos#updateFrequency
Label
Update Frequency
Definition
The period in which a KOS is typically updated.
Comment
Suggest using DCMI Collection Description Frequency Vocabulary. (http://dublincore.org/groups/collections/frequency/) .
Has Domain
Has Range
Expected value literal

Section 4. Re-used Properties

Audience
Term Name dct:audience
IRI http://purl.org/dc/terms/audience
Label
Audience
Definition
A class of entity for whom the resource is intended or useful.
Has Domain
NKOS Usage Note
Recommend using a controlled vocabulary.
Has Range
Expected value IRI of an agent class.


Contact
Term Name dcat:contactPoint
IRI http://www.w3.org/ns/dcat#contactPoint
Label
Contact
Definition
Links an asset to a contact point from where further information about an Asset can be obtained.
Has Domain
Has Range
Expected value literal


Date Created
Term Name dct:created
IRI http://purl.org/dc/terms/created
Label
Date Created
Definition
Date of creation of the resource.
Has Domain
NKOS Usage Note
Core element. For the date of a manifestation, use dct:issued
Has Range
Expected value literal


Creator
Term Name dct:creator
IRI http://purl.org/dc/terms/creator
Label
Creator
Definition
An entity primarily responsible for making the resource.
Comment
Examples of a Creator include a person, an organization, or a service.
Has Domain
NKOS Usage Note
Core element
Has Range
Expected value IRI of an Agent


Described by
Term Name wdrs:describedBy
IRI http://www.w3.org/2007/05/powder-s#describedby
Label
Described by
Definition
The relationship A 'describedby' B asserts that resource B provides a description of resource A.
Comment
There are no constraints on the format or representation of either A or B, neither are there any further constraints on either resource.
Has Domain
Has Range
Expected value IRI of a work; IRI of an expression


Description
Term Name dct:description
IRI http://purl.org/dc/terms/description
Label
Description
Definition
An account of the resource.
Comment
Description may include but is not limited to: an abstract, a table of contents, a graphical representation, or a free-text account of the resource.
Has Domain
Has Range
Expected value literal


Format
Term Name dct:format
IRI http://purl.org/dc/terms/format
Label
Format
Definition
The file format, physical medium, or dimensions of the resource.
Comment
Examples of dimensions include size and duration. Recommended best practice is to use a controlled vocabulary such as the list of Internet Media Types [MIME] http://www.iana.org/assignments/media-types/.
Has Domain
Has Range
Expected value literal


Identifier
Term Name dct:identifier
IRI http://purl.org/dc/terms/identifier
Label
Identifier
Definition
An unambiguous reference to the resource within a given context.
Comment
Recommended best practice is to identify the resource by means of a string conforming to a formal identification system.
Has Domain
NKOS Usage Note
Core element
Has Range
Expected value identifier


Is embodiment of
Term Name frbrer:isEmbodimentOf
IRI http://iflastandards.info/ns/fr/frbr/frbrer/P2004
Label
Is embodiment of
Definition
Relates a manifestation to an expression that is embodied in the manifestation.
Has Domain
NKOS Usage Note
Core element
Has Range
Expected value IRI of an expression


Is Part Of
Term Name dct:isPartOf
IRI http://purl.org/dc/terms/isPartOf
Label
Is Part Of
Definition
A related resource in which the described resource is physically or logically included.
Has Domain
NKOS Usage Note
A related KOS, in which the described KOS is logically included. This is different from nkos:basedOn relationship type. Consult KOS Relation Vocabulary for examples and possible extended properties http://wiki.dublincore.org/index.php/NKOS_Vocabularies .
Has Range
Expected value IRI of a work; IRI of an expression; IRI of a manifestation


Is Realization Of
Term Name frbrer:isRealizationOf
IRI http://iflastandards.info/ns/fr/frbr/frbrer/P2002
Label
Is Realization Of
Definition
Relates an expression to the work that is realized through the expression.
Has Domain
NKOS Usage Note
Core element
Has Range
Expected value IRI of a work


Date Issued
Term Name dct:issued
IRI http://purl.org/dc/terms/issued
Label
Date Issued
Definition
Date of formal issuance (e.g., publication) of the resource.
Has Domain
NKOS Usage Note
Core element
Has Range
Expected value literal


Language
Term Name dct:language
IRI http://purl.org/dc/terms/language
Label
Language
Definition
A language of the resource.
Comment
Recommended best practice is to use a controlled vocabulary such as RFC 4646 [RFC4646].
Has Domain
Has Range
Expected value language code


Date Modified
Term Name dct:modified
IRI http://purl.org/dc/terms/modified
Label
Date Modified
Definition
Date on which the resource was changed.
Has Domain
Has Range
Expected value literal


Publisher
Term Name dct:publisher
IRI http://purl.org/dc/terms/publisher
Label
Publisher
Definition
An entity responsible for making the resource available.
Comment
Examples of a Publisher include a person, an organization, or a service.
Has Domain
Has Range
Expected value IRI of an agent


Relation
Term Name dct:relation
IRI http://purl.org/dc/terms/relation
Label
Relation
Definition
A related resource.
Comment
Recommended best practice is to identify the related resource by means of a string conforming to a formal identification system.
Has Domain
Has Range
Expected value IRI of a work; IRI of an expression; IRI of a manifestation  


Rights
Term Name dct:rights
IRI http://purl.org/dc/terms/rights
Label
Rights
Definition
Information about rights held in and over the resource.
Comment
Typically, rights information includes a statement about various property rights associated with the resource, including intellectual property rights.
Has Domain
Has Range
Expected value rights statement


Sample
Term Name adms:sample
IRI http://www.w3.org/ns/adms#sample
Label
Sample
Definition
Links to a sample of an Asset (which is itself an Asset).
Has Domain
NKOS Usage Note
A link to a fragment of the resource.
Has Range
Expected value IRI of an expression


Subject
Term Name dct:subject
IRI http://purl.org/dc/terms/subject
Label
Subject
Definition
The topic of the resource.
Comment
Typically, the subject will be represented using keywords, key phrases, or classification codes. Recommended best practice is to use a controlled vocabulary.
Has Domain
NKOS Usage Note
Core element
Has Range
Expected value IRI of a thema


Title
Term Name dct:title
IRI http://purl.org/dc/terms/title
Label
Title
Definition
A name given to the resource.
Has Domain
NKOS Usage Note
Core element
Has Range
Expected value literal


Type
Term Name dct:type
IRI http://purl.org/dc/terms/type
Label
Type
Definition
The nature or genre of the resource.
Comment
Recommended best practice is to use a controlled vocabulary. To describe the file format, physical medium, or dimensions of the resource, use the Format element.
Has Domain
NKOS Usage Note
Type of knowledge organization system or structure. Recommend use of KOS Types Vocabulary [http://w3id.org/nkos/nkostype ]. Core element.
Has Range
Expected value IRI of a KOS type



Derived From
Term Name prov:wasDerivedFrom
IRI http://www.w3.org/ns/prov#wasDerivedFrom
Label
Derived From
Definition
A derivation is a transformation of an entity into another, an update of an entity resulting in a new one, or the construction of a new entity based on a pre-existing entity.
Has Domain
NKOS Usage Note
Derived From covers relationships between resources such as translation-of, abridgement-of, extension-of, and version-of. It is different from Part Of relationship type. Consult KOS Relation Vocabulary for examples and possible extended properties http://wiki.dublincore.org/index.php/NKOS_Vocabularies .
Has Range
Expected value IRI of an expression