Modeling Time Information in Manufacturing

Abstract

This paper describes a concept of a central modeling system for time information and a methodology to realize it. First, the importance of developing temporal modeling systems which are commonly used by application programs is discussed from the viewpoint of computer-integrated manufacturing. After analyzing the diversity of temporal information to be considered, a unified representation method of various temporal information is proposed and its mathematical formalization is explained. According to the proposed approach, an experimental system, time information manager, is implemented. The system adopts J.F. Allen's method as a consistency management algorithm. The system is also extended so as to deal with cyclic time intervals, the multiple time axes, and qualitative information. It is applied to some present methodologies concerned with time information to evaluate the effectiveness of the proposed methodology.