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Journal of Applied Nonlinear Dynamics
Miguel A. F. Sanjuan (editor), Albert C.J. Luo (editor)
Miguel A. F. Sanjuan (editor)

Department of Physics, Universidad Rey Juan Carlos, 28933 Mostoles, Madrid, Spain


Albert C.J. Luo (editor)

Department of Mechanical and Industrial Engineering, Southern Illinois University Ed-wardsville, IL 62026-1805, USA

Fax: +1 618 650 2555 Email:

Correction to the Unknown Input Observer Design for Linear Fractional-Order Time-Delay Systems and a New Enhanced LMI Condition

Journal of Applied Nonlinear Dynamics 7(1) (2018) 73--79 | DOI:10.5890/JAND.2018.03.006

Y. Boukal$^{1}$,$^{2}$,$^{3}$, M. Darouach$^{1}$, M. Zasadzinski$^{1}$, N.E. Radhy$^{2}$

$^{1}$ Université de Lorraine, Centre de Recherche en Automatique de Nancy (CRAN UMR-7039, CNRS), IUT de Longwy, 186 rue de Lorraine 54400, Cosnes et Romain, France

$^{2}$ Université Hassan II, Faculté des Sciences Ain-Chock, Laboratoire Physique et Matériaux Microélectronique Automatique et Thermique BP: 5366 Maarif, Casablanca 20100, Morocco

$^{3}$ Université de Valenciennes, CNRS, UMR 8201, LAMIH, Laboratoire d'Automatique de Mécanique et d'Informatique Industrielles et Humaines, 59313 Valenciennes, France

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This note considers the work entitled “Unknown Input Observer Design for Linear Fractional-Order Time-Delay Systems”. In the above paper [1], the authors gave the existence conditions of such observer, then based on the fractional order Lyapunov stability approach, a sufficient condition for the asymptotic stability of the estimation error have given in a linear matrix inequality (LMI) formulation which is incorrect. In this note, we give the correction of Theorem 7. The new proposed Theorem can be applied to a large kind of delayed fractional-order-system when the delay is time varying or constant, while the above mentioned paper consider only a constant time delay. The proof is based on the diffusive representation of the fractionalorder derivative and the indirect Lyapunov approach proposed in [2].


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