Reenterable colored Petri net model of Ebola virus dynamics

An early-developed technique for modeling cellular automata by colored Petri nets has been further refined with regard to the model transformation into the reenterable form. A reenterable model contains each component in a single copy, which makes it invariant to the actual connection of components and the definite topology of the modeled system. The cellular automaton of Burkhead and Hawkins for modeling Ebola virus dynamics possesses a regular topology given by a square plain lattice. Within the reenterable model, each token is supplied with a topology tag that specifies the token location within the lattice using a pair of indexes. A check of neighbors' state regarding a definite neighborhood, Moore for the automaton in question, is implemented via a check of tokens having the corresponding value of indexes with respect to the index difference specified by the set -1, 1. A reenterable model is rather convenient for simulation and model-driven development of treatment prescriptions because it does not require graphical editing, supposing modification of the model parameters only, represented by constants in the model declarations section. This especially concerns the lattice size, which can be rather large compared to the number of cells in the deceased organ. A series of simulations acknowledges that the model behavior closely corresponds to the behavior of either the source cellular automata or the conventional colored Petri net model. Thus, the reenterable format is recommended as a reference concept for modeling viruses with Petri nets.