Ontological engineering is a successor of knowledge engineering which has been considered as a technology for building knowledge-intensive systems. Although knowledge engineering has contributed to eliciting expertise, organizing it into a computational structure, and building knowledge bases, AI researchers have noticed the necessity of a more robust and theoretically sound engineering which enables knowledge sharing/reuse and formulation of the problem solving process itself. Knowledge engineering has thus developed into “ontological engineering” where “ontology” is the key concept to investigate. Although the necessity of an ontology and ontological engineering is well-understood, there has been few success stories about ontology construction and its deployment to date. The reason for this is that the principles of ontology design is not clear enough. Therefore, a methodology of ontology design and a computer system supporting ontology design are needed. Our research goals include a methodology of ontology design, and development of an environment for building and using ontologies. This article outlines an environment for building and using ontologies “Hozo” which is under development. Hozo is designed based on a fundamental consideration of an ontological theory. And it has been extensively used in many projects to develop various ontologies. As an example, this paper presents an activity of ontology construction and its deployment in an interface system for an oil-refinery plant operation which has been done under the umbrella of Human-Media Project for five years. And we demonstrate the ability of Hozo through the ontology building/using process.
