Finite automata are probably best known for being equivalent to right-linear context-free
grammars and, thus, for capturing the lowest level of the Chomsky-hierarchy, the family of …

Descriptional complexity is the study of the conciseness of the various models representing
formal languages. The state complexity of a regular language is the size, measured by the …

A discrete event system possesses the property of detectability if it allows an observer to
perfectly estimate the current state of the system after a finite number of observed symbols …

Many type systems include infinite types. In session type systems, infinite types are important
because they specify communication protocols that are unbounded in time. Usually infinite …

Unambiguous automata, ie, nondeterministic automata with the restriction of having at most
one accepting run over a word, have the potential to be used instead of deterministic …

We investigate the descriptional complexity of the nondeterministic finite automaton (NFA) to
the deterministic finite automaton (DFA) conversion problem, for automata accepting …

Modeling all aspects of a complex system within a single model is a difficult, if not
impossible, task. Multi-view modeling is a methodology where different aspects of the …

A language L is prefix-closed if, whenever a word w is in L, then every prefix of w is also in L.
We define suffix-, factor-, and subword-closed languages in an analogous way, where by …

Motivated by security and privacy considerations in applications of discrete event systems,
we describe and analyze the complexity of verifying various state-based notions of opacity in …

In this paper we consider the computational complexity of the following problems: given a
DFA or NFA representing a regular language L over a finite alphabet Σ, is the set of all …