Fig. 4
From: The effects of pressure- versus volume-controlled ventilation on ventilator work of breathing

Effect of changing I:E ratio (1/4, 1/3, 1/2 and 1/1) on inspiratory flow profile under a constant tidal volume of 0.5 L, in a square flow waveform, b sinusoidal flow waveform, c decelerating flow waveform