JourneyStar, is an Rdf-star-based ontology to represent complex metadata-oriented travel data (historical or modern). This ontology contains definition of classes and properties necessary to represent travel data with all its associated metadata as a knowledge graph. The meta-level information can be added to the the edges of the graph using RDF-star technology to comprehensively represent the complexity of the travel data. We have illustrated use-case of the ontology constructs through multiple examples. The resulting RDF-star based knowledge graphs can be stored in triplestores which support RDF-star such as GraphDB and the graph can be then efficiently queried using SPARQL-star. To verify the data and ensure the consistency of the data with the ontology, SHACL node and property shapes are defined and made openly-accessible along with the ontology. You can find the ontology, and SHACL graphs, both serialized in Turtle format, with various usage examples here.

Description of the Ontology

JourneyStar, is an OWL ontology that contains description of various classes and predicates needed to represent travel accounts as linked open data. Since RDF-star makes embedding triples directly within other triples possible, we can represent the core statements with their metadata as an annotated triples where the core triples take the subject or object positions. In the ontology, we have defined properties for this that can be used for annotated triples.

To keep this ontology generic, we have employed the existing ontologies and extended the existing definitions of the classes and properties in other ontologies such as schema and Trip through defining subclasses. The ontology serialized in Turtle can be found here.

This ontology has the prefix js and the namespace http://journey-star.dhlab.unibas.ch/ontology/JourneyStar#.

<http://journey-star.dhlab.unibas.ch/ontology/JourneyStar> rdf:type owl:Ontology ;
                                       rdfs:comment "An RDF-star-based ontology to represent travel data." ;
                                       owl:versionInfo "v.1.0" .

Below we describe a few main classes and properties of this ontology with a few graphics.

Note: in all of the graphics below the following prefixes are used:

@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
@prefix currencyA: <https://spec.edmcouncil.org/fibo/ontology/FND/Accounting/CurrencyAmount/> .
@prefix currency: <https://spec.edmcouncil.org/fibo/ontology/FND/Accounting/ISO4217-CurrencyCodes/>.
@prefix schema: <https://schema.org/> .
@prefix dbr: <http://dbpedia.org/resource/> .
@prefix dbo: <http://dbpedia.org/ontology/> .
@prefix trip: <http://ontology.eil.utoronto.ca/icity/Trip/> .
@prefix activity: <http://ontology.eil.utoronto.ca/icity/Activity/> .
@prefix js: <http://journey-star.dhlab.unibas.ch/ontology/JourneyStar#> .
@prefix js-shacl: <http://journey-star.dhlab.unibas.ch/shacl/js-shacl#> .
@prefix : <http://journey-star.dhlab.unibas.ch/data/JourneyStar#> .

Classes

Location

The js:Location is an OWL class representing a location/place such as a city, lake, mountain, village, etc. which have geo-coordinates and preferably a GeonameID (from Geonames database, retrievable also from Wikidata) so that they can be uniquely identified.

IRI: <http://journey-star.dhlab.unibas.ch/ontology/JourneyStar#Location>
has super class:
      dbo:Place   
      schema:Pace

is domain of:
      js:hasGeonameID  (max cardinality 1, range: xsd:string)
      js:hasWikiLink   (max cardinality 1, range: IRI)
      schema:name      (range: xsd:string, permitted language tags "en", "de", "fr", "es")

Corresponding SHACL node shape:
      js-shacl:LocationShape

Below, you can see an example of an RDF representation of a location:

Location Representation

Person

The js:Person is an OWL class representing a person who undertakes a journey or is involved in a journey (such as: hotel owner, waiter/waitress, travel companion, etc.).

IRI: <http://journey-star.dhlab.unibas.ch/ontology/JourneyStar#Person>
has super class:
      schema:Person

is domain of:
      schema:name        (min cardinality 1, range: xsd:string)
      schema:givenName   (range: xsd:string)
      schema:familyName  (range: xsd:string)
      schema:gender      (restricted to schema:Male, schema:Female, and xsd:string)
      schema:birthDate   (max cardinality 1, range: xsd:date)
      schema:birthPlace  (max cardinality 1, range: IRI)
      schema:knows       (range js:Person, js:Location)  
      js:participatedIn  (range js:Event)
      js:hasGnd          (max cardinality 1, range: xsd:string)

Corresponding SHACL node shape:
      js-shacl:PersonShape

Below, you can see an example of an RDF representation of a person:

Person Representation

Event

The js:Event is a general OWL class describing an an event in a real world with spatiotemporal data and participants. An event can be an activity such as a journey, sightseeing, excursion, dining, etc, or an occurrence such as encounter with a person, or even a natural phenomena.

IRI: <http://journey-star.dhlab.unibas.ch/ontology/JourneyStar#Event>

is domain of:
      js:hasParticipant  (range IRI)
      js:hasLocation     (range: xsd:string, js:Location, xsd:anyURI, IRI)
      js:hasDate         (range: xsd:date, xsd:dateTime)


Corresponding SHACL node shape:
      js-shacl:EventShape

There are various classes that are defined as subclass of the js:Event each with their specific predicates, for example:

  • js:Activity that has predicates to describe the a physical activity such as a movement.
  • js:Occurrence with properties to describe an occurrence.
  • js:NaturalPhenomena representing a natural phenomena.

Activity

The js:Activity is a general OWL class describing an activity a person undertakes, this can be a journey, sightseeing, excursion, dining, etc.

IRI: <http://journey-star.dhlab.unibas.ch/ontology/JourneyStar#Activity>
has super class:
      activity:Activity, js:Event

is domain of:
      schema:name  (min cardinality 1, range: xsd:string)
      js:hasCost   (max cardinality 1, range: xsd:decimal)

Corresponding SHACL node shape:
      js-shacl:ActivityShape

There are various classes that are defined as subclass of the js:Activity each with their specific predicates, for example:

  • js:Dining that has predicates to describe the cuisine and type of the meals.
  • js:Sightseeing with properties to describe the building or monument.
  • js:Trip representing a movement from one place to another.

Dining

The js:Dining is a general OWL class describing the act of dining during a journey.

IRI: <http://journey-star.dhlab.unibas.ch/ontology/JourneyStar#Dining>
has super class:
      js:Activity

is domain of:
      js:mealType  (range: xsd:string)
      js:cuisine   (range: xsd:string)

Corresponding SHACL node shape:
      js-shacl:DiningShape

SightSeeing

The js:SightSeeing is a general OWL class describing the act of sight-seeing during a journey.

IRI: <http://journey-star.dhlab.unibas.ch/ontology/JourneyStar#SightSeeing>
has super class:
      js:Activity

is domain of:
      js:sightingOf  (min cardinality 1, range: xsd:string, IRI, or xsd:anyURI)

Corresponding SHACL node shape:
      js-shacl:SightSeeingShape

Journey

The js:Journey is an OWL class that represents a journey a person undertakes from place A to place B. This journey can be a long one lasting for months or a short one for a few days.

IRI: <http://journey-star.dhlab.unibas.ch/ontology/JourneyStar#Journey>
has super class:
      trip:Trip
      js:Activity

is domain of:
      js:origin                (min cardinality 1, range: IRI or xsd:anyURI)
      js:destination           (min cardinality 1, range: IRI or xsd:anyURI)
      js:startDate             (max cardinality 1, range: xsd:date , xsd:dateTime)
      js:endDate               (max cardinality 1, range: xsd:date , xsd:dateTime)
      js:hasActivity           (range: js:Activity)
      js:hasStay               (range: js:Stay)
      js:meanOfTransportation  (range: range: IRI or xsd:anyURI)
      js:transitThrough        (range: range: IRI or xsd:anyURI)

Corresponding SHACL node shape:
      js-shacl:JourneyShape

There are metadata information accompanying the travel information, for example when we say person X went from A to B, there is a metadata information about the time the person left location A (departure date) and the time, person arrives to the destination (arrival date). These meta-level information can be added to the edges of the graph representing the origin and destination, respectively through predicates js:arrivalDate and js:departureDate.

Note: The predicates of the star (annotated) triples, such as js:arrivalDate and js:departureDate, do not have domain restriction, and can be used with subjects of any type, even a triple!

Excursion

The js:Excursion is an OWL class that represents a short (one day) round trip a person undertakes without overnight stay. This class is distinct from js:Journey in that the origin and destination of this kind of trip is the same.

IRI: <http://journey-star.dhlab.unibas.ch/ontology/JourneyStar#Excursion>
has super class:
      trip:Trip

different from:
      js:Journey

Corresponding SHACL node shape:
      js-shacl:ExcursionShape

Accommodation

The class js:Accommodation represents an accommodation. It can be any kind of shelter used to spend a night in during a journey; such as hotel, hostel, rented room, tent, cave, etc.

IRI: <http://journey-star.dhlab.unibas.ch/ontology/JourneyStar#Accommodation>
has super class:
      dbo:Building
      dbo:Shelter

is domain of:
      schema:name     (min cardinality 1, range: xsd:string)
      schema:adress   (range: xsd:string)
      js:hasLocation  (range: xsd:string, js:Location, xsd:anyURI, IRI)

Corresponding SHACL node shape:
      js-shacl:AccommodationShape

Stay

The class js:Stay represents an overnight stay in a location in an accommodation which is represented by a resource of type js:Accommodation class.

IRI: <http://journey-star.dhlab.unibas.ch/ontology/JourneyStar#Stay>
has super class:
    js:Activity

is domain of:
      js:hasAccommodation  (range:  js:Accommodation or any IRI)
      js:startDate         (max cardinality 1, range: xsd:date or xsd:dateTime)
      js:endDate           (max cardinality 1, range: xsd:date or xsd:dateTime)

Corresponding SHACL node shape:
      js-shacl:StayShape

Additionally, the currency type can be added to the edge representing js:hasCost using RDF-star so that not only the cost of the accommodation, can be stored, the currency of the amount is also stored with it. The currency types can be found in the currency data graph.