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...ely related to the size of the independence relation. So introducing time (and its implicit synchronizations) will necessarily restrict the corresponding relation for the associated untimed model. In =-=[4, 18]-=-, the authors define an alternative semantics for NTA based on local time elapsing. Despite the fact that this semantics allows more behaviours than the standard semantics, the reachability relation a...

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...med case and thus make the application of partial order reduction difficult. An improvement which identifies additional cases where reduction can be applied is presented in [DGKK98]. Bengtsson et al. =-=[BJLW98]-=- were the first to suggest a modified semantics that allows the component automata of a network to execute individually, synchronizing their local time scales only on synchronization transitions. Our ...

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...grated to other formalisms like real-time versions of Petri Nets [5] and ModeCharts [15]. As future work, we would like to adapt some recently presented optimization techniques to our framework (e.g. =-=[9, 19, 4]-=-). In particular, we believe that partial order techniques (see. [4]) can be adapted to check LDI which deppend on the locations of just one automaton of a parallel composition. Acknowledgements: We t...

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...hat the translation is compositional does not only simplify the translation task, but also let us profit from partial order and compositional techniques already developed for timed automata (see e.g. =-=[32, 10, 31, 12]-=-). Related Work The aim of our work is to allow the possibility of verification on a stochastic model by translating it into a non-stochastic model. In this way we loose the measure of the property th...

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...d [18, 19]. A zone represents allowed execution traces in the circuit. A different ordering on a set of concurrent transitions, however, can lead to a different zone. This creates an exponential branching in the timed state space. As the zone is a partially ordered set relating various transition times, it is possible to reduce branching in the timed state space by adding fewer relations to the set. Local time semantics and partially ordered sets (POSETs) remove orderings in the zone on sets of independent concurrent signal transitions reducing the representation size of the timed state space [20, 21, 22, 23, 24, 25]. POSET reduction in the timing analysis of Timed Petri nets (TPN)—Petri nets with timers on the places—yields a significant reduction in the number of zones associated with each marking [24]. The algorithm in [24] implements the POSET reduction on concurrent independent signal transitions. It explicitly models, however, timers on the places; thus, it needlessly considers many redundant orderings of firings of these timers [21]. An optimization to the POSET algorithm removes some redundant orderings of concurrent place timer firings, but this optimization is limited to specific timing conditio...

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...d on independence of transitions. In this paper we present a partial order reduction technique for real-time systems, which is guided by the structure the component based system being analyzed. As in =-=[3,16]-=- we use local time semantics to increase independence. For timed automata the implicit synchronization of global time restricts independence of actions. For our component model we note that the separa...

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...on of a graph which is a single large automaton that produces the same behaviours as the NTA or the TPN; this induces an exponential blow up in the size of the system to be analysed. Related Work. In =-=[13,18]-=-, the authors define an alternative semantics for NTA based on local time elapsing. The efficiency of this method depends on two opposite factors: local time semantics generate more states but the ind...