Nonlinear Time Domain Relation between Respiratory Phase and Timing of the First Heart Sound

<div>Approximation performance of the Hammerstein-Wiener model for subject #2 with varied polynomial order. (a) MSE decreased with the polynomial order; (b) fitness value increased with the polynomial order.</div>

Computational and Mathematical Methods in Medicine

fig7

Figure 7

Figure 7: Nonlinear Time Domain Relation between Respiratory Phase and Timing of the First Heart Sound 