edited by Masami Ito (Kyoto Sangyo University, Japan) & Teruo Imaoka (Shimane University, Japan)

The research results published in this book range from pure mathematical theory (semigroup theory, discrete mathematics, etc.) to theoretical computer science, in particular formal languages and automata. The papers address issues in the algebraic and combinatorial theories of semigroups, words and languages, the structure theory of automata, the classification theory of formal languages and codes, and applications of these theories to various areas, like quantum and molecular computing, coding theory, and cryptography.

• Semidirect Products with the Pseudovariety of All Finite Group (J Almeida & A Escada)
• On the Sentence Valuations in a Semiring (A Atanasiu et al.)
• Arithmetical Complexity of Infinite Words (S V Avgustinovich et al.)
• R-Trivial Languages of Words on Countable Ordinals (O Carton)
• Networks of Watson–Crick D0L Systems (E Csuhaj-Varjú & A Salomaa)
• On the Differentiation Function of Some Language Generating Devices (J Dassow)
• Quantum Finite Automata (J Gruska & R Vollmar)
• Error-Detecting Properties of Languages (S Konstantinidis)
• Power Semigroups and Polynomial Closure (S W Margolis & B Steinberg)
• Routes and Trajectories (A Mateescu)
• A Proof of Okninski and Putcha's Theorem (K Shoji)
• Tree Automata in the Theory of Term Rewriting (M Steinby)
• and other papers