Database Reference
In-Depth Information
Every Farm is a kind of Place.
Every Farm has part a Building.
Every Farm has part a Field.
Every Farm is intended for
Agricultural Production.
Class: Farm
SubClassOf: Place that hasPart
some Building and hasPart some
Field and isIntendedFor some
AgriculturalProduction
A farm is something that has a specific location, comprises at least a building and a
field, and is intended for Agricultural Production. As you can see from the Manchester
OWL syntax, we take the union (using either “and” or “that”) of these sentences
describing a Farm, and the class Farm becomes a subclass of those Places that also
have a Building part and a Field part and are intended for Agricultural Production.
At this point, it is worth noting that Merea Maps has reused the class Place
described previously in the ontology and reused the “has part” property from the
Mereology ontology. It has also introduced the new classes of Building, Field, and
Agricultural Production along with the properties “has a part” and “is intended for”;
at this stage, they have not described them further even though they are either core
classes or properties.
Merea Maps next choose to describe a school. Again, they can say that it is a
Place and also that it must comprise at least one building. It also has a well-defined
purpose: that of providing education. So, Merea Maps can therefore provide the
following minimal description of a school:
Every School is a kind of Place.
Every School has part a Building.
Every School is intended for
Education.
Class: School
SubClassOf: Place that hasPart
some Building and isIntendedFor
some Education
10.4.4.3 Developing Patterns
From this, it can be seen that a pattern is beginning to emerge: that of a combina-
tion of location, physical construction, and purpose. Indeed, we find that this pattern
can be reused for many different classes of things—factories, hospitals, universities,
airports, and so on. All of these will have a specific location, buildings, and purpose.
A common factor of many ontologies is that class descriptions conform to a rela-
tively small number of patterns. Such patterns are more normally discovered rather
than designed from the outset, but an important thing to remember is that they will
not be discovered unless you look for them.
In the examples given so far, all have buildings, but there are other things where
buildings are not mandatory—a golf course, for example. Many golf courses
will have buildings (a clubhouse, maintenance buildings, and so on), but none is
mandatory. So, we can provide the following description:
Every Golf Course is a kind of
Place.
Every Golf Course has part Golf
Links.
Every Golf Course is intended for
Leisure.
Class: GolfCourse
SubClassOf: Place that hasPart
some GolfLinks and isIntendedFor
some Leisure
