21,369 research outputs found
Zonotopic fault detection observer design for Takagi–Sugeno fuzzy systems
This paper considers zonotopic fault detection observer design in the finite-frequency domain for discrete-time Takagi–Sugeno fuzzy systems with unknown but bounded disturbances and measurement noise. We present a novel fault detection observer structure, which is more general than the commonly used Luenberger form. To make the generated residual sensitive to faults and robust against disturbances, we develop a finite-frequency fault detection observer based on generalised Kalman–Yakubovich–Popov lemma and P-radius criterion. The design conditions are expressed in terms of linear matrix inequalities. The major merit of the proposed method is that residual evaluation can be easily implemented via zonotopic approach. Numerical examples are conducted to demonstrate the proposed methodPeer ReviewedPostprint (author's final draft
On the nonintegrability of equations for long- and short-wave interactions
We examine the integrability of two models used for the interaction of long
and short waves in dispersive media. One is more classical but arguably cannot
be derived from the underlying water wave equations, while the other one was
recently derived. We use the method of Zakharov and Schulman to attempt to
construct conserved quantities for these systems at different orders in the
magnitude of the solutions. The coupled KdV-NLS model is shown to be
nonintegrable, due to the presence of fourth-order resonances. A coupled real
KdV - complex KdV system is shown to suffer the same fate, except for three
special choices of the coefficients, where higher-order calculations or a
different approach are necessary to conclude integrability or the absence
thereof.Comment: 9 pages, presented as a poster at The Tenth IMACS International
Conference on Nonlinear Evolution Equations and Wave Phenomena: Computation
and Theor
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