Yuji Naka

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Ontologies reflect our view of what exists and developing ontologies for a given domain requires a common context. This context can be characterized explicitly by means of an upper ontology. Upper ontologies define top-level concepts such as physical objects, activities, mereological and topological relations from which more specific classes and relations(More)
— This paper focuses on an automated batch manufacturing system with material-handling robots (MHRs) and material-processing robots (MPRs). In this robotic manufacturing system, materials transported by the MHRs are processed by the MPRs. These operations cause a bottleneck in the system. Furthermore, the bottleneck induces congestion of the MHRs. In the(More)
— This paper describes a methodology regarding an autonomous cruise control (ACC) of circulating multi-robot which is directly effective for solving the congestion regardless of the presence of a bottleneck. For this purpose, we focus on an external interaction force between the robots. This force is generated with the use of a virtual damper. In this(More)
In their effort to improve safety, process industries have relied on a variety of information systems for managing safety. However, current information systems are limited in their ability to integrate information along the life-cycle. This paper proposes a Hazop support system, which has three functions as follows. (F1) An intelligent CAD system (DFD,(More)
AbstrAct Deliberate exploitation of natural resources and excessive use of environmentally abhorrent materials have resulted in environmental disruptions threatening the life support systems. A human centric approach of development has already damaged nature to a large extent. This has attracted the attention of environmental specialists and policy makers.(More)