Time in Structured Occurrence Nets

This paper presents a new tool-supported formalism based on collections of related timed occurrence nets, namely, timed structured occurrence nets (timed sons) for the modelling and analysis of causally-related events and concurrent events with uncertain or missing time information in evolving systems of systems. The application domain of timed sons includes accident and crime investigations. A global discrete time model is used to support consistent causal reasoning about a system and time intervals are used to capture uncertainty about time values. We define the timed sons notation and conditions for checking the consistency of time information, present algorithms of linear computational complexity for estimating missing time intervals using default duration intervals and redundant time information, and describe the facilities provided by the SONCraft tool.