Comment on “Bisimilarity control of partially observed nondeterministic discrete event systems and a test algorithm” [Automatica 47 (2011) 782–788]

An article on bisimilarity enforcing supervisory control of discrete event systems was published recently in 2011, Issue 4, Volume 47, pages 782–788, of Automatica. The article introduced a certain definition of composition of plant and supervisor to define a controlled system, so as to come up with an existence condition of bisimilarity enforcing control. Such definition changes the semantics of event-based control to transition-based control, selectively disabling nondeterministic transitions. Any results reported in the paper thus raise question about value and applicability.