General Conclusion - Geographical Information Retrieval in Textual Corpora - page 99

4.2.2.1. Relations in the sentence
We are interested in the relations between relevant phrases for a given IR need. In
thiscontext,thereexistsapropositionoftheW3Caimingatthemodelingofrelations
between phrases composing a sentence.
- N-ary relations.
The W3C 3 presents n-ary relations according to four use cases. The resource
description framework/RDF schema (RDF/RDFS) or web ontology language (OWL)
languages being devoted to the representation of binary relations, the main objective
of this recommendation is to issue propositions adapted to the representation of
relations of degrees higher than two.
Four use cases are thus proposed by the W3C. Cases 1 and 2 correspond to
forms of extension of binary relations. Cases 3 and 4 describe the establishment of
a relationship between several arguments considered to be equal in their participation
in the modeled relation. We illustrate these four cases very briefly as follows:
1) “Marco reached the inn of Platane by walking until Pagolle” illustrates a
relation between a person, an object (place) and an additional piece of information
detailing the entirety of this relation.
2) “Marco reached the inn of Platane from where a txistu tune was coming”
illustrates a relation between a person, an object (place) and an additional piece of
information relative to this object.
3) “MarcoplaysthetxistuattheinnofPlatane,afterthemid-daymeal”illustrates
arelationbetweenapersonandseveralindependentarguments,which,generally,give
it a meaning: who does what, where, when, how and why? Grammatically, there is no
differencewiththefirstcase.Semantically,themeaningoftheargumentsallowsusto
differentiate the two cases.
4) “Marco visited the village of Pagolle, then the pass of Osquich and finally, the
chapelofSaint-Antoine”illustratesarelationbetweenapersonandalistofarguments
(places); the chronology of the enumeration is important.
Figure 4.8 proposes a simplified representation of these four cases of n-ary
relations of the W3C. Thus, in the previous examples, case 1 corresponds to a
relation containing one or more arguments, these arguments corresponding to the
additional pieces of information describing the relation between the subject and the
object; case 2 corresponds to a relation containing one or more argument describing
the object of the initial relation; case 3 corresponds to a relation containing several
connected but independent arguments; finally, case 4 corresponds to a relation
3 http://www.w3.org/TR/swbp-n-aryRelations/.