Fig. 1. Furnace mouth flame spectrum data sets

Fig. 2. Flowchart of WCARS

Fig. 3. Variation of RMSE with the number of windows

Fig. 4. Rough selection result of WCARS

Fig. 5. Variation of RMSE with the number of selected variables
(a): ISPA; (b): SPA

Fig. 6. Selection result of characteristic wavelengths with WCARS-ISPA

Fig. 7. Training results of the WCARS-ISPA model