Fig. 4: SVM classifications of low-humidity gases.
Schematic diagram (a) for gas data acquisition and gas species identification. b Mixed gas at a 1:1 ratio of NH3 to NO2 and c data at mixture ratios of 1:3 and 3:1. d PCA plots after feature extraction: the data exhibit a constant degree of dispersion for the mixed gas. Confusion matrix for e NH3–NO2, f NH3–NO, and g NO2–NO mixed gases after feature selection. h Comparison of the classification rate of the Boruta algorithm with feature selection and SVM analysis without feature selection under conditions of low humidity
