Generalized Synchronization Trees

This paper develops a generalized theory of synchronization trees. In their original formulation, synchronization trees modeled the behavior of nondeterministic discrete-time reactive systems and served as the foundational theory upon which process algebra was based. In this work, a more general notion of tree is proposed that is intended to support the modeling of systems with a variety of notions of time, including continuous and hybrid versions. (Bi)simulation is also studied, and it is shown that two notions that coincide in the discrete setting yield different relations in the generalized framework. A CSP-like parallel composition operator for generalized trees is defined as a means of demonstrating the support for compositionality the new framework affords.