Application of Wavelet Multi-Scale Piecewise Direct Standardization on Near Infrared Analysis Calibration
Piecewise direct standardization(PDS) is the most popular method on near infrared analysis calibration transfer.One of the disadvantages of PDS is that the window widths are the same in the whole near infrared(NIR) spectral wavelengths as the window width is too large in some spectra region and too small in the others.A new calibration transfer method based on PDS was proposed to improve the calibrated results,the new method is wavelet multi-scale piecewise direct standardization(WMPDS).It was used for calibration transfer in NIR analysis of mixed amine.Wavelet transfer(WT) was conducted to discompose NIR data and then PDS was applied to correct the wavelet coefficients.The window widths of PDS were changed as the wavelet coefficients changed and the reconstruction of the coefficient was next to the correction of PDS.WMPDS can well correct the differences between instruments and improve analytical accuracy greatly.The performance of WMPDS is better than that of PDS in NIR calibration transfer.