Timing anomalies are characterized by counterintuitive timing behaviour. A locally faster execution leads to an increase of the execution time of the whole program. The presence of such behaviour makes WCET analysis more difficult: It is not safe to assume local worst-case behaviour wherever the analysis encounters uncertainty. Existing definitions of… (More)
Automata are a useful tool in infinite state model checking, since they can represent infinite sets of integers and reals. However, analogous to BDDs to represent finite sets, an obstacle of an automata-based set representation is the sizes of the automata. In this paper, we generalize the notion of " don't cares " for BDDs to word languages as a means to… (More)
— Hard real-time systems need methods to determine upper bounds for their execution times, usually called worst-case execution times. Timing anomalies are counter-intuitive conditions in which a local speed-up of an instruction results in a global slowdown. Modern efficient timing analysis tools may yield inaccurate results when applied to processors with… (More)
Many applications in eLearning utilize wireless networks (WLAN) as a carrier for data and communication. These networks in their basic form are insecure, protecting the communication is a precondition for using a WLAN for confidential contents. Many existing solutions either do not provide the neccessary security or fail when employed with large user bases.… (More)
Automata-based decision procedures have proved to be a particularly useful tool for infinite-state model checking, where automata are used to represent sets of real and integer values. However, not all theoretical aspects of these decision procedures are completely understood. We establish triple exponential upper bounds on the automata size for was… (More)
Taking advantage of idleness to reduce dropped frames and memory consumption.
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