Section: New Results

Definition of the BioRica platform

Participants : David James Sherman [ correspondant ] , Macha Nikolski, Grégoire Sutre, Alice Garcia.

A major development in 2005-9 was the development of BioRica, an extension of the AltaRica modeling language for complex industrial systems. BioRica is a high-level modeling framework integrating discrete and continuous multi-scale dynamics within the same semantics domain, while offering an easy to use and computationally efficient numerical simulator. It is based on a generic formalism that captures a range of discrete and continuous formalisms and admits a precise operational semantics. BioRica models have a corresponding compositional semantics in terms of an extension of Generalized Markov Decision Processes. This semantics allowed us to prove that BioRica models admit an operational semantics in terms of continuous stochastic processes, and that this operational semantics is correctly simulated by the discrete event stepper used during numerical simulation.

The simulation schema for a given BioRica node is given by a hybrid algorithm that deals with continuous time and allows for discrete events that roll back the time according to these discrete interruptions. Time advances optimally either by the maximal step size defined by an adaptive integration algorithm, or by discrete jumps defined by the minimal delay necessary for firing a discrete event.

BioRica is instantiated in a software platform for modeling and simulation, that has recently been adopted by the INRIA through a Technology Development Action (ADT).