An inference engine for RDF - Agfa

An inference engine for RDF
The Semantic Web is a very new field of research. This makes it necessary to
test a lot in order to avoid ending with theoretic constructions that are not usable
in daily practice. This makes testcases a very important subject.
I will discuss here the most important testcases. Pieces of source code will be
given in RDFProlog syntax. The full original sources are given in appendix 3.
5.17.2. Gedcom
Gedcom is a system that was developed to provide a flexible, uniform format for
exchanging computerized genealogical data. The gedcom testcase of De Roo
[DEROO] gives a file with rules and file with facts. A query can then be done.
This testcase is very good for testing a more complex chaining of rules; also for
testing with a large set of data.
Example rule:
gc:parent(Child, Parent),gc:sex(Parent, male) :> gc:father(Child, Parent).
Two facts:
gc:parent(frank, guido),gc:sex(guido, male).
The query:
gc:father(Who, guido)
will give as solution:
gc:father(frank, guido).
5.17.3. The subClassOf testcase
This testcase is an example where a general rule (with a variable predicate) will
cause looping if there is no anti-looping mechanism available.
It contains following facts and rules:
a(rdfs:subClassOf, owl:TransitiveProperty)
a(P, owl:TransitiveProperty), P(C1, C2), P(C2, C3) :> P(C1, C3).
Given the facts:
rdfs:subClassOf (mammalia, vertebrae).
rdfs:subClassOf (rodentia, mammalia)
and the query:
rdfs:subClassOf(What, vertebrae).
The result will be:
rdfs:subClassOf(mammalia, vertebrae).
rdfs:subClassOf(rodentia, vertebrae).
5.17.4. An Alpine club
Following example was taken from [CLUB].
Brahma, Vishnu and Siva are members of an Alpine club.
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