On Consistency and Merge of Modal Transition Systems

Imperial College of Science, Technology and Medicine Department of Computing Foundations for Behavioural Model Elaboration Using Modal Transition Systems PhD Thesis

Modal Transition Systems (MTS) are an extension of Labelled Transition Systems (LTS) that have been shown to be useful to reason about system behaviour in the context of partial information. MTSs distinguish between required, proscribed and unknown behaviour and come equipped with a notion of refinement that supports incremental modelling where unknown behaviour is iteratively elaborated into r...

On Modal Refinement and Consistency

Almost 20 years after the original conception, we revisit several fundamental questions about modal transition systems. First, we demonstrate the incompleteness of the standard modal refinement using a counterexample due to Hüttel. Deciding any refinement, complete with respect to the standard notions of implementation, is shown to be computationally hard (co-NP hard). Second, we consider four ...

Labelled transition systems as a Stone space

A fully abstract and universal domain model for modal transition systems and refinement, developed in [27], is shown to be a maximal-points space model for the bisimulation quotient of labelled transition systems over a finite set of events. In this domain model we prove that this quotient is a Stone space whose compact, zero-dimensional, and ultra-metrizable Hausdorff topology measures the deg...

Modal Transition Systems: A Foundation for Three-Valued Program Analysis

We present Kripke modal transition systems (Kripke MTSs), a generalization of modal transition systems [27,26], as a foundation for three-valued program analysis. The semantics of Kripke MTSs are presented by means of a mixed power domain of states; soundness and consistency are proved. Two major applications, model checking partial state spaces and three-valued program shape analysis, are pres...

merge of translation vol.17- No.3 June 2020