Modeling Hybrid Systems in SIMTHESys

Abstract

Hybrid systems (HS) have been proven a valid formalism to study and analyze specific issues in a variety of fields. However, most of the analysis techniques for HS are based on low-level description, where single states of the systems have to be defined and enumerated by the modeler. Some high level modeling formalisms, such as Fluid Stochastic Petri Nets, have been introduced to overcome such difficulties, but simple procedures allowing the definitions of domain specific languages for HS could simplify the analysis of such systems. This paper presents a stochastic HS language consisting of a subset of piecewise deterministic Markov processes, and shows how SIMTHESys – a compositional, metamodeling based framework describing and extending formalisms – can be used to convert into this paradigm a wide number of high-level HS description languages. A simple example applying the technique to solve a model of the energy consumption of a data-center specified using Queuing Network and Hybrid Petri Nets is presented to show the effectiveness of the proposal

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