Abstract
An ontology comprises the explicitly articulated and shared concepts of a knowledge community or domain. These concepts are arranged formally in a taxonomy and are governed by specifically defined rules and axioms. Ontologies often play an important role in knowledge management information technology (KMIT). An enterprise knowledge management IT system, for example, may use an ontology “to facilitate communication, search, storage, and [knowledge] representation” (O’Leary, 1998, p. 58). A general survey of the literature suggests that ontologies are capable of improving performance in a large variety of knowledge management IT functions, especially relative to knowledgebases for best practices, lessons learned, human resource skills, Help Desks, FAQs, document collections, standards and regulations, products, services, proposals, and the like. In addition, as we look to the future, ontologies will function centrally in agent-mediated knowledge management (AMKM), distributed knowledge management (DKM), and the Semantic Web (Daconta, Obrst, & Smith, 2003; Fensel, 2001; Heflin, Volz, & Dale, 2002; McGuiness, 2002), as these technologies become pervasive in a global economy that distributes KM knowledgebases across companies and cultures.
Key Terms in this Chapter
Taxonomy: (is-a) : An ordered list of taxa or categories. A subordinate taxon (category) inherits the defining characteristics of its superordinate (parent) taxon. Example : An automobile has all the characteristics of its superclass, vehicle , but not of its sibling class truck .
Subsumption: An entity exists in a subsumption relationship to another entity when it falls in a directly lower class in the taxonomy. The subsumed entity inherits the characteristics of the classes above it. Example : The term dog exists in a subsumption relationship to the family Canidae, and inherits canine characteristics; dog does not, however, exist in a subsumption relationship to the family Felidae, so logically cannot inherit feline or cat-like characteristics.
Extension: A class definition that simply lists or enumerates all class members (mathematical sets and subsets). Example : the class of US automobile manufacturers would be extensionally defined by listing all the manufacturers.
Intension: A class definition that states necessary attributes or criteria of membership inclusion or exclusion. Example : the class of U.S. automobile manufacturers would be intensionally defined by listing the criteria of membership, such as plant location, ownership, headquarters location, and the like.
Axiom: A rule or maxim accepted as a truth in the ontology. Axioms provide the inferencing or logical power of the ontology. Example : “If and only if a wine is red, then it is derived from a grape that is red.”
Partonomy: (part-of) : A realization of mereology that specifies in a subsumption hierarchy the relationship of parts to the whole. Example : A whole wooden pencil consists of these parts: wooden shaft, paint, embossed logo, graphite core, eraser, and the like.
Conceptualization: A model of reality, a generalized abstraction of particular items. Example : A radio exists physically, but when conceptualized it exists symbolically as some form of knowledge representation: a word, picture, diagram, graph, or formula.