Calibration Transfer in the Automated Detection of Acetone by Passive Fourier Transform Infrared Spectrometry

Abstract

The qualitative determination of acetone is performed by passive Fourier transform infrared (FT-IR) spectrometry with data spanning two spectrometers. Digital filtering and piecewise linear discriminant analysis techniques are optimized and applied directly to short interferogram segments to eliminate background and instrument variation and then perform pattern recognition. Once optimized, this methodology classifies remote sensing data into categories representing the presence or absence of the analyte in an automated fashion. The addition to the training set of small numbers of interferogram data from a second spectrometer is evaluated in the creation of qualitative models robust with respect to differences between the instruments. Results of these experiments show that classification percentages averaged across all tested interferogram segments are improved from 76.2 ± 6.4% to 95.1 ± 2.2% with the addition of as few as 10 background interferograms collected in the field with the secondary instrument. The results also demonstrate that a broader, more optimal range of segments in the interferogram can be utilized when these background data are added from the secondary instrument. It is also found possible to standardize the data from the secondary instrument with blackbody background interferograms collected in the laboratory.

Automated Detection of Chemical Vapors by Pattern Recognition Analysis of Passive Multispectral Infrared Remote Sensing Imaging Data

“…Previous work in our laboratory on passive infrared rem ote sensing has focused primarily on chemical vapor detection from nonimaging hyperspectral sensors positioned on the ground. 4,9,10 In the work described here, autom ated detection algorithms are developed for use with multispectral imaging measurem ents m ade from an aircraft platform. The system is used to acquire two-dimensional images of a nitrogen fertilizer facility across 14 infrared bands.…”

Improved chemometric strategies for quantitative FTIR spectral analysis and applications in atmospheric open‐path monitoring

“…The latter technique has been employed for qualitative assays using digital filtering and piecewise-linear discriminant analysis techniques. 9 Quantitative analysis was carried out with the use of multivariate calibration based on interferogram data. 10 The potential for chemical-warfare -agent detection has motivated the military community to contribute to the development of this technique.…”

Multiple Filtering Strategy for the Automated Detection of Ethanol by Passive Fourier Transform Infrared Spectrometry

“…Work in our laboratories has focused on increasing the viability of passive FT-IR remote sensing m easurements through the development of data analysis algorithms that help to compensate for the data variance associated with changes in the background radiance. [6][7][8][9] The strategy used is to apply digital ltering techniques to the raw interferogram data collected by the FT-IR spectrometer. This approach takes advantage of the fact that the background radiance is primarily represented as a broad spectral feature whose representation in the interferogram is constrained to the region near the point of zero path difference (ZPD).…”