RichMorin: Automated import of articles

2010-07-27T20:55:15Z

Automated import of articles

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== Ontology ==

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An [[{{#var:G}}Ontology|ontology]] is a formally-defined vocabulary
for a particular domain of interest.
Because it is formally defined,
it can reduce the opportunity for confusion in human discourse.
Indeed, some ontologies are created for this exact purpose.

However, ontologies are typically created
to enable a computer program (eg, a [[{{#var:G}}Reasoner|reasoner]])
to infer logical consequences about the domain.
So, developing an ontology might be a precursor
to creating a [{{#var:wp}}/Database}} database],
[{{#var:wp}}/Expert_system expert system],
or [{{#var:wp}}/Knowledgebase knowledge base].

The restriction to "a particular domain of interest" may seem odd.
However, there are both practical and theoretical reasons
for limiting the subject matter and the encoded information.
In brief, the problem is that the meaning of a term
depends on the kinds of questions being asked.

For example, even something as prosaic as an onion
will be seen in different ways
to a biologist, a cook, a farmer, and a grocer.
Details which are critical to one person
may be completely irrelevant to another.

==== Structure ====

An [[{{#var:G}}OWL|OWL]] ontology (as used in {{#var:Pr4}}) is based on a
[[{{#var:G}}Class|class]] [[{{#var:G}}Hierarchy|hierarchy]].
Each class defines a level of [[{{#var:G}}Abstraction|abstraction]].
For example, the [[Pr4_UG_ex_Pizza|Pizza Ontology]] defines classes
such as <tt>Pizza</tt>, <tt>VegetarianPizza</tt>, and <tt>Margherita</tt>.

The hierarchy is then "decorated" with [[{{#var:G}}Property|properties]].
Each property specifies a binary (ie, dyadic, two-ended) relationship.
A relationship might indicate that a <tt>Pizza</tt> has:

* a <tt>PizzaBase</tt>,
* one or more <tt>PizzaTopping</tt>s, or
* certain standardized sizes.

Because of [[{{#var:G}}Inheritance|inheritance]], <tt>Pizza</tt>'s
[[{{#var:G}}Descendant_Class|descendant classes]]
(eg, <tt>VegetarianPizza</tt>, <tt>Margherita</tt>) also have these properties.


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RichMorin: Automated import of articles