Circadian phase re-setting using nonlinear output-feedback contrOL

Long Tonthat, Zhengtao Ding

    Research output: Contribution to journalArticlepeer-review


    Circadian rhythms occupy an important role in daily biological activities of living species. Circadian disorder is a phenomenon of circadian rhythms which occurs when internal rhythms cannot keep up with the changes of external environment rhythms. Changes of environmental rhythms, presented by the change of light/dark cycles or by irregular rhythms, result in phase shifts between internal and external rhythms. The existence of these phase shifts in longer term has negative effect to health. Therefore, in biological study of circadian rhythms, finding a method to recover the shifted phases to their normal rhythms, which is also the treatment of circadian disorder, is an important required task. In this paper, we propose a control design method to reset the circadian phases. The phase restoration is carried out by the synchronization of trajectories generated from a controlled model with the trajectories of a reference system via nonlinear control design using only one measurement. Both reference and controlled systems are based on a given 3rd order model of Neurospora circadian rhythms. The two other unknown states are estimated using a recently developed nonlinear observer for the output-feedback control. © 2012 World Scientific Publishing Company.
    Original languageEnglish
    Pages (from-to)1-19
    Number of pages18
    JournalJournal of Biological Systems
    Issue number1
    Publication statusPublished - Mar 2012


    • Biological Systems
    • Nonlinear Control Systems
    • State Estimations


    Dive into the research topics of 'Circadian phase re-setting using nonlinear output-feedback contrOL'. Together they form a unique fingerprint.

    Cite this