- Friedrich Otto (Kassel, Germany)
Title: A Survey on Automata with Translucent Letters
Abstract: In this survey, we present the various types of automata with translucent letters that have been studied in the literature. These include the finite automata and the pushdown automata with translucent letters, which are obtained as reinterpretations of certain cooperating distributed systems of a restricted type of restarting automaton, the linear automaton with translucent letters, and the visibly pushdown automaton with translucent letters. For each of these types of automata with translucent letters, it has been shown that they accept those trace languages which are obtained from the class of languages that is accepted by the corresponding type of automaton without translucent letters.
- György Vaszil (Debrecen, Hungary)
Title: Membrane computing and Petri nets
Abstract: When looking at the computations of membrane systems and the behavior of place/transition Petri nets, we might notice several features which are related to each other. Petri net transitions consume tokens from their input places and produce new tokens at their output places, so in some sense they behave similarly to membrane systems which consume, produce, and move objects around in the regions of their membrane structure. Based on these relationships, the functioning of place/transition nets can naturally be described by transformations of multisets corresponding to possible token distributions on the places of the net, while different kinds of objects and object evolution rules in different compartments of a membrane system can be represented by the places and transitions of a Petri net.
In the talk we look in more detail at these structural links between the two models which, on one hand, motivate the examination of membrane systems from the point of view of the concurrent nature of their behavior, and on the other hand, inspires the study of Petri net variants suitable for the modeling of membrane system computations.