New approach to generalized two-dimensional correlation spectroscopy. II: Eigenvalue manipulation transformation (EMT) for noise suppression.

Young Mee Jung; Seung Bin Kim; Isao Noda

doi:10.1366/000370203321666597

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New approach to generalized two-dimensional correlation spectroscopy. II: Eigenvalue manipulation transformation (EMT) for noise suppression.

Young Mee Jung·Seung Bin Kim·Isao Noda

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Abstract

This paper introduces the concept of eigenvalue manipulating transformation (EMT) of a data matrix for noise suppression in two-dimensional (2D) correlation spectroscopy. The FT-IR spectra of a polystyrene/methyl ethyl ketone/toluene solution mixture during the solvent evaporation process, to which were added a substantial amount of artificial noise, have been analyzed. By uniformly raising the power of a set of eigenvalues, the major eigenvalues become more prominent. As a consequence, minor eigenvectors representing the noise component are no longer strongly represented in the reconstructed data. This EMT operation is similar to the simple truncation of noise-dominated minor factors practiced in standard principal component analysis (PCA), as demonstrated in our preceding paper on PCA-2D correlation spectroscopy. The effect of this new EMT scheme is more gradual, with attractive flexibility to continuously fine-tune the balance between the desired noise reduction effect and the retention of pertinent spectral information.

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Algorithms Artifacts Butanones Polystyrenes Principal Component Analysis Quality Control Reproducibility of Results Sensitivity and Specificity Solutions Solvents Spectroscopy, Fourier Transform Infrared Statistics as Topic Stochastic Processes Toluene Comparative Study Evaluation Study Journal Article Research Support, Non-U.S. Gov't Validation Study

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Young Mee Jung, Seung Bin Kim, Isao Noda. 2003. New approach to generalized two-dimensional correlation spectroscopy. II: Eigenvalue manipulation transformation (EMT) for noise suppression.. https://doi.org/10.1366/000370203321666597

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