Comparing disjunctive modal transition systems with an one-selecting variant

Abstract

An expressive class of abstractions for labeled transition systems is that of disjunctive modal transition systems ( DMTS ), featuring may- and must transitions as well as disjunctive hypertransitions ( OR). In order to describe exclusive choice adequately, we develop a variant of DMTS s called 1-selecting modal transition systems ( OMTS ) that, roughly speaking, interprets hypertransitions exclusively ( XOR). These abstract models, DMTS s and OMTS s, are compared with respect to their expressive power. By giving transformations or showing their non-existence, we show that the two setting can express the same sets of labeled transition systems, but 1-selecting modal transition systems have a richer refinement preorder.