Dynamics and Control

, Volume 6, Issue 3, pp 227–261 | Cite as

On structured perturbations for two classes of linear infinite-dimensional systems

  • Z. Emirsajlow
  • A. J. Pritchard
  • S. Townley


This paper considers two classes of infinite-dimensional systems described by an abstract differential equationx (t) = (A + BΔC)x(t),x(0) =x0, on a Hilbert space, whereA, B, C are linear, possibly unbounded operators and Δ is an unknown, linear, bounded perturbation. The two classes of systems are defined in terms of properties imposed on the triple (A, B, C). It is proved that for every Δ the perturbed system (A + EΔF, B, C) inherits all the properties of the unperturbed system {A, B, C}) if (A, E, F) and {A, B, F} are in the same class.


Hilbert Space Unbounded Operator Unperturbed System Bounded Perturbation Structure Perturbation 
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Copyright information

© Kluwer Academic Publishers 1996

Authors and Affiliations

  • Z. Emirsajlow
    • 1
  • A. J. Pritchard
    • 2
  • S. Townley
    • 3
  1. 1.Institute of Control EngineeringTechnical University of SzczecinSzczecinPoland
  2. 2.Control Theory CentreUniversity of WarwickCoventryUK
  3. 3.Department of MathematicsUniversity of ExeterExeterUK

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