On supremal languages of classes of sublanguages that arise in supervisor synthesis problems with partial observation (Q1108988)

This paper characterizes the class of closed and (M,N)-recognizable languages in terms of certain structural aspects of relevant automata. This characterization leads to algorithms that effectively compute the supremal (M,N)-recognizable sublanguage of a given language. One of these algorithms is used, in an alternating manner with an algorithm which yields the supremal \((\Sigma_ u,N)\)-invariant sublanguage, to compute the supremal sublanguage of a given language that is both \((\Sigma_ u,N)\)-invariant and (M,N)-recognizable. Finite convergence of the resulting algorithm is proved. An example illustrates the use of these algorithms.