Fig. 2
From: Non-linear parameters of specific resistance loops to characterise obstructive airways diseases
Panel I Geometrical parameters in COPD subject: a Area of the loop, b Roundness, c Median point, d Asynchrony, e sG0.5. Panel II Examples of input–output relationship presented over time: a Healthy subject, b Asthma subject, c COPD subject; Solid line represents flow (model output), dashed line is volume shift (model input). Transfer function model explains how input transforms to output. Panel III Visualisation of model performance with modelled expiration (red line) over the original loop (blue line): a Healthy subject (NMRSE = 95%), b Post methacholine asthma subject (NMRSE = 92%), c COPD subject (NMRSE = 94%)