Algebraic Approach to Timed Petri Nets with Applications to Communication Networks
نویسندگان
چکیده
In this diploma thesis, we define a formalism for a time-extension to classic P/T (or Petri-)nets. This allows time durations to be assigned to transitions of a P/T net, representing delays present in the systems that are being modelled, which in turn influence (restrict) the firing behaviour of the nets. This is especially useful when modelling time-critical systems. The new contribution of this thesis is comprised of the definition of categories for the timed net classes of timed P/T nets, timed P/T systems and timed P/T states, as well as functorial relations between these categories. One main result is the existence of morphisms for all three net classes that preserve firing behaviour, as well as structuring techniques for timed P/T nets. Another result is the equivalence of the categories of timed P/T systems and states. Zusammenfassung dieser Diplomarbeit wird ein Formalismus für eine erweiterung von klassischen P/TNetzen um einen Zeitbegriff formuliert. Dies ermöglicht es, transitionen eines P/TNetzes Zeitdauern zuzuweisen, die Verzögerungen in den zu modellierenden Systemen repräsentieren. Diese Zeitdauern beeinflussen wiederum das Schaltverhalten des Netzes, wodurch eine Modellierung von zeitkritischen Systemen vereinfacht wird. Der neue Beitrag dieser Arbeit besteht in der Definition von Kategorien für die timed Netz-Klassen der timed P/T-Netze, timed P/T-Systeme und timed P/T-Zustände, sowie funktorielle Beziehungen zwischen diesen Kategorien. Das erste Hauptergebnis ist die Existenz von Morphismen für alle drei Netzklassen, die das Schaltverhalten bewahren, sowie Strukturierungstechniken für timed P/T-Netze. Ein weiteres Ergebnis ist die Kategorieäquivalenz der Kategorien der timed P/TSysteme und timed P/T-Zustände.
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