application • construction space ontology
EXAMPLE For instance, the class StorageArea would contain all the individuals that are storage areas in our domain of interest which might be ElectricalMaterial_StorageArea or InstrumentationMaterial_StorageArea. Classes are organized into a superclass-subclass hierarchy. Subclasses specialize (‘are subsumed by’) their superclasses. Another example could regard the classes MicroLevelSpace and LaborCrewSpace. A Labor Crew Space is defined as subclass of MicroLevelSpace, meaning that ‘All labor crew spaces are micro-level spaces’ and ‘All individuals (user-setted) of the class LaborCrewSpace, for every given construction method, will be automatically members of the class MicroLevelSpace’.
5.3 Topological structure Here, the framework models of the ‘space ontology’ is depicted in terms of classes, properties and relations, by mean of the same text notation introduced in the previous Figure 5.2. As before mentioned, core class of the space ontology is ConstructionMethod. It is the first user interface regarding the ontology compilation and comprise all those data that shall be provided for the workspace planning in the prosed system architecture. It means that the user adds individuals to all those classes, described below, the ontology is made of. Each construction method isDefinedBy a WorkDescription. A WorkDescription defines a Demand in terms of Procedure and SafetyRule. A Demand requires some Resources. Different classes of Resources are defined according to the Scheduling Ontology but regarding the matter in question, care should be taken on the class SpatialResource. A Spatial Resource shall occupy a Micro-Level-Workspace. To manage this relation a cardinality restriction1, which specifies the exact number of relationships that an individual must participate in, is added (Figure 5.4). Instead a Minimum Cardinality Restriction is used to ensure that the user will link at least a resource to each construction method.
1 In OWL language, we can describe the class of individuals that have at least, at most or exactly a specified number of relationships with other individuals or datatype values. The restrictions that describe these classes are known as Cardinality Restrictions. For a given property P, a Minimum Cardinality Restriction specifies the minimum number of P relationships that an individual must participate in. A Maximum Cardinality Restriction specifies the maximum number of P relationships that an individual can participate in. A Cardinality Restriction specifies the exact number of P relationships that an individual must participate in.
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