In this paper we prove a lower bound for the maximum state complexity of Deterministic Finite Cover Automata (DFCAs) obtained from Non-deterministic Finite Automata (NFAs) of a given state complexity n, in case of a binary alphabet. We show, for binary alphabets, that the difference between maximum ...

Regex are used in many programs such as Perl, Awk, Python, egrep, vi, emacs etc. It is known that regex are different from regular expressions. In this paper, we give regex a formal treatment. We make a distinction between regex and extended regex; while regex present regular languages, extended reg...

In this paper we consider the transformation from (minimal) non-deterministic finite automata (NFAs) to deterministic finite cover automata (DFCAs). We want to compare the two equivalent accepting devices with respect to their number of states; this becomes in fact a comparison between the expressio...

Petri net modeling enables us to verify the protocol of interest formally. However, aside from formal verification, a new protocol really needs to be tested in a relatively realistic environment in which it interworks (or at least co-exists) with earlier or different versions of the same or similar ...