Fig. 4
The main procedures of cardiac cycle calculation: a is R′(m), the UACF of a heart sound with S4; b is \(E_{{R^{\prime}}} \left( m \right)\), the energy signal of R′(m); c is \(\tilde{E}_{{R^{\prime}}} \left( m \right)\); d is c without the last peak; e is RFinal, the UACF of d