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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 characterization of codiagnosability for FA and TA which extends the necessary and sufficient condition that characterizes 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. Finally we address the codiagnosis problem for TA under bounded resources and show it is 2EXPTIME-complete.

BibTeX Entry

    publisher        = {Lecture Notes in Computer Science},
    author           = {Cassez, Franck},
    month            = sep,
    editor           = {{Ahmed Bouajjani and Wei-Ngan Chin}},
    year             = {2010},
    keywords         = {fault diagnosis, discrete event systems, timed automata},
    title            = {The Complexity of Codiagnosability for Discrete Event and Timed Systems},
    booktitle        = {8th International Symposium on Automated Technology for Verification and Analysis (ATVA)},
    pages            = {82--96},
    address          = {Singapore}


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