Fig. 1. The ion mobility spectra of real liquor and liquor with different proportion of alcohol

Fig. 2. The time domain characteristic peak

Fig. 3. The frequency domain response curve of ion mobility spectrum

Fig. 4. The spectral entropy time diagram of liquor samples
(a): Real liquor; (b): Liquor added with 10% alcohol; (c): Liquor added with 20% alcohol; (d): Liquor added with 30% alcohol; (e): Liquor added with 40% alcohol; (f): Liquor added with 50% alcohol

Fig. 5. The contribution rate of features after dimension reduction using PCA

Fig. 6. The contribution rate of features after dimension reduction using LDA

Fig. 7. The optimization results of parameter C in SVM binary classification experiment

Fig. 8. The optimization results of parameter gamma in SVM binary classification experiment

Fig. 9. The optimization results of parameter C in SVM six classification experiment

Fig. 10. The optimization results of parameter gamma in SVM six classification experiment