FIT Božetěchova 2, lecture room C228, 12:00-13:00, 2.11.2011
The seminar is organized by the Formal Model Research Group at the Department of Information Systems, Faculty of Information Technology, Brno University of Technology. As its central scientific topic, it discusses formal models and their applications. Recent presentations are to be found at http://www.fit.vutbr.cz/~meduna/work/doku.php?id=talks:seminar.
Author: P. Dömösi (College of Nyíregyháza, Hungary)
Title: Something About Cryptography
Abstract: Symmetric and asymetric cryptosystems are considered including Polybius cryptosystem, Caesar code, Richelieu cryptosystem, Enigma, Purple, Navajo code, DES, RSA, Pretty Good Pryvacy. In addition a novel symmetric cryptosystem is shown.
Author: Géza Horváth (University of Debrecen, Hungary)
Title: The Language of Primitive Words
Abstract: A nonempty word is said to be primitive if it is not a proper power of another word. A number of papers investigated the language of all primitive words over an alphabet with more than one letter, concerning its relation to the Chomsky hierarchy. In  the authors conjectured that this language is not context-free. This twenty years old conjecture is still open. In this talk I will present recent results and our ongoing research on this topic.