The Identity of Resources on the Web ontology (IRW).
type: Ontology
imports: informationrealization.owl
version info: Created by Valentina Presutti with support from Harry Halpin and Aldo Gangemi
comment: This ontology is an evolution of IRE ontology. It describes identification of resources on the Web, through the definition of relationships between resources and their representations on the Web. The requirement is to describe what can be identified by URIs and how this is handled e.g. in form of HTTP requests and reponds.

semantic web uri
type: Class
subclass of: Restriction
  min cardinality: 1
  on property: redirects to
comment: The subset of URI that identify typically analog things. In general they identify any resource but are not directly resolvable. They do not identify an accessible information resource.They act as a virtual delegate for exactly one resource, typically analog. They cause a re-direct or any other type of mechanism that makes the web server resolve another URI that is associated with a WebReource (see range of redirectTo)
subclass of: uri

redirects to
type: ObjectProperty
domain: uri
range: Class
  intersection of: uri
  intersection of: Restriction
    all values from: web resource
    on property: identifies
sub property of: accesses
comment: Redirections can be used outside the Semantic Web between just normal information resources, their domain and range says nothing about the type of resource. The only important aspect is that the reseource that is the destination of the redirection must be associated with a WebRepresentation, hence it must be a WebResource. This property can be used as top property for expressing special types of redirections e.g. TAG's 303 redirection or hash convention.

uri
type: Class
subclass of: Restriction
  cardinality: 1
  on property: has URI string value
subclass of: Restriction
  min cardinality: 1
  on property: identifies
subclass of: resource

has URI string value
type: DatatypeProperty
comment: The value of the URI, a string compliant with the URI specification.
range: anyURI
domain: uri
comment: The name of this datatype property previously was "hasURI", but in this ontology a URI is modelled as a class, hence I though that it's better to clarify, even in the property name that it refers to the string value of a URI.
type: FunctionalProperty

identifies
type: ObjectProperty
inverse of: is identified by
domain: uri
range: Thing
range: resource
comment: The relashionship between a URI and a resource. A URI identify only one resource, it acts as a "virtual" delegate for that resource on the Web. This is different from the refersTo relashionships. This latter holds between Resources, and it's not functional. For example, http://www.example.com#me identifies only john, while john's homepage http://www.example.com/john.html refersTo me, the place where he works, his job, his personal interests, etc. If I want to describe John's characteristics e.g. his name, age, etc. on the Web, I will attach them to http://www.example.com#john. On the other hand, http://www.example.com/john.html identifies john's homepage, which is an information resource.
type: FunctionalProperty

resource
type: Class
comment: This class is meant to express the same intuition of rdfs:Resource but it is defined here in order to have OWL-DL compaibility. In an OWL Full version of this ontology we would have this class owl:equivalentClass rdfs:Resource.
subclass of: Thing
equivalent class: Class
  union of: information resource
  union of: non-information resources

information resource
type: Class
disjoint with: InformationRealization
disjoint with: awww representation
disjoint with: Nothing
equivalent class: InformationObject
comment: They are *about* something, this something can be everything (rdfs:Resource, owl:Thing, ire:Entity) including AnalogResource. Their essential characteristics can be conveyed in a single message. They can be associated with a URI, and can have a WebRepresentation, in this case they are called WebResource. They have some realization, for example: the text of Moby Dick is an InformationResource, a book containing the text of Moby Dick is one of its realization. The intuition behind the class InformationResource is the same behind the class ir:InformationRealization (cloned from Dolce Ultra Lite).
subclass of: resource
disjoint with: non-information resources

physical resource
type: Class
comment: Something that occupies its own space and has its own mass in the real world, and can have a "virtual delegate" on the Web. For example physical people, artifacts, places, bodies, chimical substances, biological entities, etc.
disjoint with: abstract resource
subclass of: non-information resources
disjoint with: conceptual resource

awww representation
type: Class
subclass of: Restriction
  on property: encoded in
  cardinality: 1
comment: The realization of a message encoding that 'goes on the wire' according to an interaction protocol (e.g. http) in order to resolve a Web accessible resource. Representation have neither a URL nor a URI, they are associated with the URL of the Web Resource they represent. Representation are disjoint with Web resources
subclass of: InformationRealization
disjoint with: Nothing
disjoint with: information resource

non-information resources
type: Class
subclass of: resource
subclass of: Restriction
  on property: is identified by
  all values from: semantic web uri
disjoint with: information resource
comment: All Semantic Web resources that are not information resources. They include abstract, conceptual, and physical resources.

encoded in
type: FunctionalProperty
type: ObjectProperty
inverse of: encodes
domain: awww representation
range: media type

web client
type: Class
subclass of: resource

is identified by
type: ObjectProperty
domain: Thing
inverse of: identifies
range: uri
domain: resource

web server
type: Class
subclass of: Restriction
  min cardinality: 1
  on property: is resolution of
subclass of: resource

is resolution of
type: ObjectProperty
sub property of: requests
inverse of: resolves to
range: uri
domain: web server

web resource
type: Class
subclass of: Restriction
  on property: is identified by
  min cardinality: 1
subclass of: Restriction
  min cardinality: 1
  on property: isRealizedBy
subclass of: Restriction
  all values from: awww representation
  on property: isRealizedBy
subclass of: information resource
comment: InformationResources that have at least one WebRepresentation and at least a URI. For example, a WebResource containing the text of Moby Dick and its WebRepresentation encoded in HTML in English language.

abstract resource
type: Class
subclass of: non-information resources
disjoint with: conceptual resource
comment: Abstract things. They are combinatorial spaces. They cannot be located in space-time. Examples are: the infinite set of integers, real numbers, formal entities, relations, functions, the infinite set of names that can be defined in namespaces.
disjoint with: physical resource

conceptual resource
type: Class
disjoint with: abstract resource
subclass of: non-information resources
comment: Resources that are created in the social communication process. A conceptual resource does not exist if it's not in a social communication. For example: legal entities, political entities, social relations, concepts, etc.
disjoint with: physical resource

media type
type: Class
subclass of: resource

is location of
type: ObjectProperty
inverse of: located on
range: awww representation
domain: web server
comment: A relation between a WebServer and a WebRepresentation. It indicates that a WebServer concretely can respond to an HTTP request with a particular Web Representation.

located on
type: ObjectProperty
comment: A relation between a WebRepresentation and a WebServer, indicating that the WebRepresentation can be obtained by e.g. an HTTP request to the WebServer.
inverse of: is location of
range: web server
domain: awww representation

is topic of
type: ObjectProperty
domain: resource
range: information resource
inverse of: is about

is about
type: ObjectProperty
domain: information resource
range: resource
inverse of: is topic of

is requested by
type: ObjectProperty
domain: uri
range: web client
inverse of: requests
comment: WebClients that have requested a URI, like in typical HTTP GET requests.

requests
type: ObjectProperty
range: uri
domain: web client
comment: Expresses the notion behind of a request operation of a web client, exempliﬁed by a typical HTTP GET request.
inverse of: is requested by

is referenced by
type: ObjectProperty
sub property of: requests
range: uri
inverse of: refers to
comment: The relation between a resource and the information resource that is about it.
domain: resource

requests
type: ObjectProperty
range: uri
inverse of: accesses
domain: resource
type: TransitiveProperty

refers to
type: ObjectProperty
comment: The relation between a URI and the resources it refers to.
domain: uri
inverse of: is referenced by
range: resource
sub property of: accesses

accesses
type: TransitiveProperty
domain: uri
comment: A causal connection from a resource to the thing identiﬁed.
range: resource
inverse of: requests
type: ObjectProperty

resolves to
type: ObjectProperty
inverse of: is resolution of
comment: Relates a URI to a concrete Web server, which currently is done by mapping a URI to an IP address or addresses.
domain: uri
sub property of: accesses
range: web server

encodes
type: ObjectProperty
range: awww representation
domain: media type
inverse of: encoded in