Specifying Multiple Time Granularities in Interactive Systems

Time plays an important role in interactive systems, but can be difficult to specify, particularly where temporal properties exist at several different time granularities. The relationship between different time granularities is complex and translation between them can be difficult. In this paper, we discuss this relationship and highlight the way in which translation between different time granularities within a single specification may have important consequences for system behaviour. Using the notation TRIO≠, we provide examples from an interactive case study of the ways in which system behaviour may be influ enced, and illustrate some of the potential difficulties which arise in the specification of temporal properties such as pace and regularity.