Information Technology Reference
In-Depth Information
we will obtain an URI that is completely different from the URI that we had
previously embedded. This implies that the URI, although unique, never allows
us to determine whether the embedded annotation is coherent with the content
that it represents.
The second aspect of this same rule requires the annotation, coherent with the
content, to be as updated as possible. This problem implies developing proce-
dures that are as automatic as possible, in keeping with our earlier works [3][6],
and generally with automatic annotation.
Rule 6.
Urge the shared use of ontologies, since this allows the non-explicit or
dynamic data link, the ABOX-TBOX link.
In a Web without semantics, the links are established by the author of the
content (rule 4). Yet in a Web with semantics there is also an approach where the
data link is established dynamically when a SPARQL 10 query is made. Declaring
instances of a same ontology by different authors of different webs without any
semantic data links between the webs does not imply that these data cannot be
linked afterwards. If these semantic data, which have been generated from the
same ontology, are collected or grouped by a third person who wishes to exploit
this information, then when it is all centralised in a SPARQL EndPoint 11 ,class
instances can be obtained regardless of their origin. Thus, a SPARQL query
would generate, under these conditions, a data link dynamically.
In an environment where data can be represented formally and where the
data are classified into concepts (classes) that are defined by some character-
istics (properties) and by the relations of all these elements (restrictions), the
auto-link of some semantic data is possible in their exploitation, particularly
the link between instances and classes (ABOX-TBOX), leaving the link between
instances (ABOX-ABOX) to the author of the content (rule 4).
Rule 6 is complementary to rule 4 and couldevenbeseenasarefinedextension
of rule 4. This rule facilitates the process, since just with rule 4, it is apparently
dicult to automate the data link process, a problem that disappears when this
proposal is improved.
To illustrate the meaning of the 6 rules together (including the proposed
ones), we present the following example. Let us assume that on a web page
mascotas (pets) 12 we annotate formally that bengala (bengal) is a gato (cat).
We have an ontology to do this vertebrados (verteberates) 13 , but in order to
know that this annotation matches the content we apply MD5 14 ,whichisa
hash function, to fulfil rule 5: a509d1fdbeba807da648b83d45fd8903. Thus we
could represent OWL formally as follows (line numbers have been added for the
explanations):
10 http://www.w3.org/TR/rdf-sparql-query/
11 Un "EndPoint" indica una ubicación específica para acceder a un servicio Web
mediante un protocolo y formato de datos específico.
http://www.w3.org/TR/
ws-desc-reqs/#normDefs
12 http://www.mascotas.org/tag/el-gato-bengala
13 http://www.criado.info/owl/vertebrados_es.owl
14 http://tools.ietf.org/html/rfc1321
Search WWH ::




Custom Search