Policy specifications with Timed Spider Diagrams

Spider Diagrams are a well-established visual language used to specify sets, their relationships, and constraints on their cardinalities but they have no means of specifying temporal aspects of a system. Timed Spider Diagrams are an evolution enabling the specification of temporal constraints, with a granular-based time system, for use in areas such as policy specification. In this paper we introduce event based actions to this framework and illustrate with examples from models of an automatic parking meter system, and an internet billing system.