N. Berglund
Control of Dynamic Hopf Bifurcations
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ABSTRACT.  The slow passage through a Hopf bifurcation leads to the delayed 
appearance of large amplitude oscillations. We construct a smooth scalar 
feedback control which suppresses the delay and causes the system to follow 
a stable equilibrium branch. This feature can be used to detect in time the 
loss of stability of an ageing device. As a by-product, we obtain results 
on the slow passage through a bifurcation with double zero eigenvalue, 
described by a singularly perturbed cubic Li\'enard equation.