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The complexity of codiagnosability for discrete event and timed systems


Franck Cassez



In this paper we study the fault codiagnosis problem for discrete event systems given by finite automata (FA) and timed systems given by timed automata (TA). We provide a uniform characterisation of codiagnosability for FA and TA which extends the necessary and sufficient condition that characterises diagnosability. We also settle the complexity of the codiagnosability problems both for FA and TA and show that codiagnosability is PSPACE-complete in both cases. For FA this improves on the previously known bound (EXPTIME) and for TA it is a new result. We then generalise the previous results to the case of dynamic observers. Finally we address the codiagnosis problem for TA under bounded resources and show it is 2EXPTIME-complete.

BibTeX Entry

    author           = {Cassez, Franck},
    doi              = {10.1109/TAC.2012.2183169},
    number           = {7},
    month            = jul,
    year             = {2012},
    keywords         = {fault diagnosis, discrete-event systems, timed automata},
    title            = {The Complexity of Codiagnosability for Discrete Event and Timed Systems},
    volume           = {57},
    pages            = {1752--1764},
    journal          = {IEEE Transactions on Automatic Control},
    paperurl         = {}


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