Families of dfas (fdfas) provide an alternative formalism for recognizing ω-regular languages. The motivation for introducing them was a desired correlation between the automaton states and right congruence relations, in a manner similar to the Myhill-Nerode theorem for regular languages. This correlation is beneficial for learning algorithms, and indeed it was recently shown that ω-regular lan...

Part 1. Self-reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Self reproducing Turing machines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Myhill’s characterization of r.e.-complete sets . . . . . . . . . . . . . . . . . . . . . . . . . 5 3. The Myhill-Shepherdson Theorem . . . . . . . . . ....

We review topics in the theory of cellular automata and dynamical systems that are related to the Moore-Myhill Garden of Eden theorem.

Cassel, S. 2015. Learning Component Behavior from Tests. Theory and Algorithms for Automata with Data. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1311. 70 pp. Uppsala: Acta Universitatis Upsaliensis. ISBN 978-91-554-9395-0. Formal models are often used to describe the behavior of a computer program or component. Behavioral models have man...

Hyperedge replacement grammars (HRGs, see [7, 6]) are one of the most successful formal models for the generative specification of graph languages, thanks to the fact that their language-theoretic and algorithmic properties to a great extent resemble those of contextfree grammars. Unfortunately, polynomial parsing is an exception from this general rule: graph languages generated by HRGs may be ...

In this thesis we will introduce topological automata and the topological entropy of a topological automaton, which is the topological entropy of the dynamical system contained in the automaton. We will use these notions to define a measure of complexity for formal languages. We assign to every language the topological entropy of the unique minimal topological automaton accepting it. We contrib...

In this paper we study the generating function of classes of graphs and hypergraphs For a class of labeled graphs C we denote by fC n the number of structures of size n For C de nable in Monadic Second Order Logic with unary and binary relation symbols only E Specker and C Blatter showed in that for every m N fC n satis es a linear recurrence relation fC n Pdm j a m j fC n j over Zm and hence i...

This note presents a correction to 1, Theorem 4] which provides a necessary and suucient condition for dispatchability. 1 Notation The following additional notation is introduced: The notation s L s 0 is used to denote that strings s; s 0 are equivalent under the Nerode equivalence induced by the language L.

This thesis presents new techniques for the construction and specification of linear tail-biting trellises. Tail-biting trellises for linear block codes are combinatorial descriptions in the form of layered graphs, that are somewhat more compact than the corresponding conventional trellis descriptions. Conventional trellises for block codes have a well understood underlying theory. On the other...

In this note we work with untyped lambda terms under β(η)-conversion and consider the possibility of extending Böhm’s theorem to infinite RE sets. Of course, it is well known that Böhm’s theorem will fail in general for such sets even if it holds for all finite subsets. It turns out that generalizing Böhm’s theorem to infinite sets involves three other superficially unrelated notions; namely, C...