(Received: January 5, 1998 ; Accepted for publication: March 19, 1998 ; Published on Web: June 16, 1999)
A rapid and intact method was developed for discriminating plastics tips by the analysis of 1/f fluctuation of near-infrared reflection spectra. First, the regression lines of the power spectrum of a given sample are obtained after middle pass filtering with FFT. Then the data point of the cross section and slope of the obtained regression line are plotted. According to our test measurement, eighteen samples were clearly classified into five groups of different chemical compositions. This novel method was found to be useful for recycling plastics waste efficiently and with reasonable accuracy.
Keywords: FFT, Plastic waste, Near-infrared spectrum, Data mining, 1/f fluctuation
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