This paper examines the concept of simulation from
a modelling viewpoint. How can one Mealy machine simulate the other one? We create formalism for simulation of Mealy machines.
The injective s–morphism of the machine semigroups induces the simulation of machines . We present the example of s–morphism
such that it is not a homomorphism of semigroups. The story for the
surjective s–morphisms is quite different. These are homomorphisms
of semigroups but there exists the surjective s–morphism such that it does not induce the simulation.
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