Interval semantics for Petri nets with inhibitor arcs

Interval semantics of elementary Petri nets with inhibitor arcs is discussed. First an operational semantics in terms of interval orders is provided, and next the concept of interval process is introduced, discussed, and used to describe concurrent histories of such nets. It is shown that the interval process semantics is equivalent to recently proposed interval traces semantics. It is also proven that if operational semantics is restricted to stratified orders (i.e. step sequences) the proposed model is equivalent to models based on step processes and comtraces.