Kouji Kozaki

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We have developed an environment for building/using ontologies, named Hozo, based on both of a fundamental consideration of an ontological theory and a methodology of building an ontology. Since Hozo is based on an ontological theory of a role-concept, it can distinguish concepts dependent on particular contexts from so-called basic concepts and contribute(More)
One of the major goals of ontology is to represent properly the underlying conceptual structure of the messy world reflecting the reality as much as possible. Ontology building tools should be designed to help developers create good ontologies. However, few of them can deal with roles adequately. Needless to say, the world is full of roles (e.g., wife,(More)
This article discusses a fundamental issues of medical ontology based on ontological theory. We focus on "anatomical structure of organs" and "abnormal states in the human body". On the basis of the investigation, we distinguish organ-specific types from those independent of any organ to maximize the explicitness of ontology. The next feature of our(More)
This paper describes a system for supporting development of ontology in a distributed manner. By a distributed manner, we mean ontology is divided into several component ontologies, which are developed by different developers in a distributed environment. The target ontology is obtained by compiling the component ontologies. These component ontologies are(More)
In Sustainability Science (SS) it is not only difficult to identify what needs to be solved but how to solve the problems once identified. There has been no consensus on underlying question of “What is structuring in SS?” This paper focuses on articulating in the form of a reference model a set of required elements, functions, and actions(More)
Ten years have passed since the concept of the semantic web was proposed by Tim Berners-Lee. For these years, basic technologies for them such as RDF(S) and OWL were published. As a result, many systems using semantic technologies have been developed. Some of them are not prototype systems for researches but real systems for practical use. The authors(More)
The RIKEN integrated database of mammals (http://scinets.org/db/mammal) is the official undertaking to integrate its mammalian databases produced from multiple large-scale programs that have been promoted by the institute. The database integrates not only RIKEN's original databases, such as FANTOM, the ENU mutagenesis program, the RIKEN Cerebellar(More)
Role is very important in ontology engineering. Although OWL has been available for ontology representation, consideration about roles is not enough. It can cause to decrease semantic interoperability of ontologies because of conceptual gaps between OWL and developers. To overcome this difficulty, this paper presents some consideration for dealing with(More)
This paper discusses Hozo’s functionality for supporting distributed and collaborative construction of ontologies. In a distributed environment, each ontology is revised asynchronously by different developers. In such a situation, one of the key issues is the maintenance of consistency among inter-dependent ontologies. In order to realize consistent(More)
This paper discusses roles from ontological point of views. We first propose a most general type including roles and role-like entities in a new way. Then, we discuss ongoing property of roles to in-depth understand temporal aspects of roles. We identify two kinds of roles: original roles and derived roles. Our new findings in this research include all(More)