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arXiv · 1909.08589

On the Maximal Parameter Range of Global Stability for a Nonlocal Thermostat Model

Patrick Guidotti·Sandro Merino
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Abstract

The global asymptotic stability of the unique steady state of a nonlinear scalar parabolic equation with a nonlocal boundary condition is studied. The equation describes the evolution of the temperature profile that is subject to a feedback control loop. It can be viewed as a model of a rudimentary thermostat, where a parameter controls the intensity of the heat flow in response to the magnitude of the deviation from the reference temperature at a boundary point. The system is known to undergo a Hopf bifurcation when the parameter exceeds a critical value. Results on the characterization of the maximal parameter range where the reference steady state is globally asymptotically stable are obtained by analyzing a closely related nonlinear Volterra integral equation. Its kernel is derived from the trace of a fundamental solution of a linear heat equation. A version of the Popov criterion is adapted and applied to the Volterra integral equation to obtain a sufficient condition for the asymptotic decay of its solutions.

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Patrick Guidotti, Sandro Merino. 2019-09-18. On the Maximal Parameter Range of Global Stability for a Nonlocal Thermostat Model. https://arxiv.org/abs/1909.08589

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