Super-Dense Computation in Verification of Hybrid CSP Processes

Hybrid Communicating Sequential Processes (HCSP) extends CSP to include differential equations and interruptions. We feel comfortable in our experience with HCSP to model scenarios of the Level 3 of Chinese Train Control System (CTCS-3), and to define a formal semantics for Simulink. The Hoare style calculus of [5] proposes a calculus to verify HCSP processes. However it has an error with respect to super-dense computation. This paper is to establish another calculus for a subset of HCSP, which uses Duration Calculus formulas to record program history, negligible time state to denote super-dense computation and semantic continuation to avoid infinite interval. It is compositional and sound.

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