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Communicating Hierarchical Transaction-based Timed Automata have been introduced to model systems performing long–running transactions. Here, for these automata a security concept is introduced, which is based on a notion of opacity and on the assumption that an attacker can not only observe public system activities, but also cause abortion of some of them. Different intruder capabilities as we...

The work presented in this Dagstuhl seminar has been done with a number of colleagues of mine and reported in the papers that are cited below. Among the interesting open problems, it is perhaps worth mentioning the following: the decidability of checking whether an analog-clock diagnoser can be represented as a timed automaton [1]; the decidability of existence of digital-clock diagnosers [12];...

This paper presents the speciication of some parts of a lip-synchronization protocol using HyCharts GSB98]. The speciication is based on a timed automata model for the protocol presented in BFK + 98]. The primary motivation of this work is to examine the utility of HyCharts for problems in the multimedia eld, in particular in comparison to timed automata AD94].

We present an approach to automatically generating invariants for timed automata models. The CIPM algorithm that we propose first computes new invariants for timed automata control locations taking their originally defined invariants as well as the constrains on clock variables imposed by incoming state transitions into account. In doing so the CIPM algorithm also prunes idle transitions, which...