The cooperation effect of noise and an external signal on implicit and explicit coherence resonances in the brusselator system

The brusselator system subject to noise and an external signal is investigated in this work. The results show that both implicit coherence resonance and explicit coherence biresonance are exhibited in the absence of external signal. When an external signal is introduced into the system, explicit coherence biresonance is eliminated, whereas implicit coherence resonance is enhanced, and the enhanced implicit coherence resonance is attributed to the internal signal generated from noise-induced oscillations, not to the external signal. When an external signal and noise are added to the same control parameter, implicit coherence resonance is enhanced; when they are added to two control parameters separately, implicit coherence resonance is suppressed. Furthermore, above the critical noise intensity, the effect of the external signal on coherent behaviors is destroyed.