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ontologies for knowledge modeling in construction planning • vito getuli
Workspaces. To schedule an Activity, it is necessary to choose Resources that produce the time intervals to assign to each activity depending on their capacity level. 11. Milestone, (Mi) = {mi1,...., min}. A Milestone represents a Phase finalization and is connected to a given Time Instant.
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4.2 Textual notations used in the body of the text in order to distinguish the ontology objects
4.3 Topological structure After having identified classes, in this paragraph is depicted the framework model of the scheduling ontology in terms of the classes, properties and relation diagrams. For readability sake and to enhance the understanding of the discussion, different font and text colors have been used to highlight ontological objects and to distinguish their belonging to the different ontologies that compose the Knowledge Base (Figure 4.2). Core class of the present ontology is ConstructionMethod, being other classes dependent on it. In fact, by using the relationships and properties listed below each construction method is described in terms of required resources, activities and workspaces. All these classes are inextricably linked in an intelligent framework. Since a ConstrucitonMethod produces or consumes a number of construction products, the class ConstructionProduct contains a list of individuals which represent the building elements (e.g. columns, beams, slabs, walls, etc) and their information requirements, and provide the main interface for connecting the scheduling problem to a given Information model IFC-based. For this reason, it follows the structure of the IFC schema and mainly includes sub-types of IfcBuildingElement. Moreover, in order to carry out a certain Construction Method within a given construction site, some Condition is implied to exist before (precondition) or after (postcondition). Also, a Construction Method isDescribedBy a WorkDescription which specifies with generic terms its execution, the allocation of spaces and the required resources. A WorkDescription, in turn, can be defined as a Procedure or a SafetyRule depending on a set of principles or conditions specified in the class Demand. This means, for example, that if the user links two workspaces to a construction method the system automatically classifies this relation depending on the workspace: a procedure if it’s a safety space, a safety
