@article {2242,
	title = {Chi-squared-based filters for high-fidelity signal-to-noise ratio enhancement of spectra},
	journal = {Applied Spectroscopy},
	volume = {62},
	number = {8},
	year = {2008},
	note = {ISI Document Delivery No.: 337EPTimes Cited: 1Cited Reference Count: 14Schulze, H. Georg Foist, Rod B. Ivanov, Andre Turner, Robin F. B.},
	month = {Aug},
	pages = {847-853},
	type = {Article},
	abstract = {When reconstructing a measured spectrum to enhance its signal-to-noise ratio (SNR), the objective is to minimize the variance between the smooth reconstructed spectrum and the original measured spectrum, hence to attain an acceptably small chi(2) value. The chi(2) value thus measures the fidelity of the reconstruction to the original. Smoothness can be conceived as attenuated variation between adjacent points in a spectrum. Thus, a conceptual change in the application of the chi(2) function to the difference between adjacent points of the reconstructed spectrum permits its use, in principle, as both a measure of smoothness and a measure of fidelity. We show here that implementations of this concept produce results superior to Savitzky-Golay filters.},
	keywords = {chi(2)-based regularization, DECONVOLUTION, ENTROPY REGULARIZATION METHOD, noise reduction, Savitzky-Golay filters, Signal-to-noise ratio enhancement, SNR, spectral smoothing},
	isbn = {0003-7028},
	url = {<Go to ISI>://000258418600003},
	author = {Schulze, H. G. and Foist, R. B. and Ivanov, A. and Turner, R. F. B.}
}
@article {1425,
	title = {Investigation of a 2D two-point maximum entropy regularization method for signal-to-noise ratio enhancement: application to CT polymer gel dosimetry},
	journal = {Physics in Medicine and Biology},
	volume = {51},
	number = {10},
	year = {2006},
	note = {ISI Document Delivery No.: 054NQTimes Cited: 13Cited Reference Count: 32},
	month = {May},
	pages = {2599-2617},
	type = {Article},
	abstract = {This study presents a new method of image signal-to-noise ratio (SNR) enhancement by utilizing a newly developed 2D two-point maximum entropy regularization method (TPMEM). When utilized as an image filter, it is shown that 2D TPMEM offers unsurpassed flexibility in its ability to balance the complementary requirements of image smoothness and fidelity. The technique is evaluated for use in the enhancement of x-ray computed tomography (CT) images of irradiated polymer gels used in radiation dosimetry. We utilize a range of statistical parameters (e.g. root-mean square error, correlation coefficient, error histograms, Fourier data) to characterize the performance of TPMEM applied to a series of synthetic images of varying initial SNR. These images are designed to mimic a range of dose intensity patterns that would occur in x-ray CT polymer gel radiation dosimetry. Analysis is extended to a CT image of a polymer gel dosimeter irradiated with a stereotactic radiation therapy dose distribution. Results indicate that TPMEM performs strikingly well on radiation dosimetry data, significantly enhancing the SNR of noise-corrupted images (SNR enhancement factors > 15 are possible) while minimally distorting the original image detail (as shown by the error histograms and Fourier data). It is also noted that application of this new TPMEM filter is not restricted exclusively to x-ray CT polymer gel dosimetry image data but can in future be extended to a wide range of radiation dosimetry data.},
	keywords = {ASTRONOMY, DECONVOLUTION, DOSE DISTRIBUTIONS, FT-RAMAN, IMAGE-RESTORATION, RADIATION, RESOLUTION, SPECTRA, TOMOGRAPHY, X-RAY},
	isbn = {0031-9155},
	url = {<Go to ISI>://000238384700016},
	author = {Jirasek, A. and Matthews, Q. and Hilts, M. and Schulze, G. and Blades, M. W. and Burner, R. F. B.}
}
@article {3347,
	title = {SNR ENHANCEMENT AND DECONVOLUTION OF RAMAN-SPECTRA USING A 2-POINT ENTROPY REGULARIZATION METHOD},
	journal = {Applied Spectroscopy},
	volume = {49},
	number = {4},
	year = {1995},
	note = {ISI Document Delivery No.: QV637Times Cited: 24Cited Reference Count: 20},
	month = {Apr},
	pages = {425-431},
	type = {Article},
	abstract = {A new method for Raman signal recovery, the two-point maximum entropy method (TPMEM), based on a regularization method using two-point entropy is presented, The method can be used for signal-to-noise ratio (SNR) enhancement in very low SNR measurements or for deconvolution, in order to remove the effects of the instrumental line shape on the measured spectrum, Unlike most SNR enhancement schemes, TPMEM requires no filter parameters and no a priori knowledge of the expected signal. A rigorous test on a randomly produced set of convolved and/or noise-corrupted simulated Raman spectra is presented in order to validate the method and compare it to Savitzky-Golay filtering and the maximum entropy method. The method is evaluated on the basis of the root mean square (rms) error and correlation coefficients of the recovered data with the original data, as well as on the basis of SNR improvement, and showed significant improvements in both performance and speed over conventional methods. The method is demonstrated in an application involving fiber-optic-linked Raman and resonance Raman spectroscopy.},
	keywords = {DECONVOLUTION, FILTERS, NOISE FILTERING, Raman spectroscopy, SNR ENHANCEMENT, TO-NOISE RATIOS},
	isbn = {0003-7028},
	url = {<Go to ISI>://A1995QV63700005},
	author = {Greek, L. S. and Schulze, H. G. and Blades, M. W. and Bree, A. V. and Gorzalka, B. B. and Turner, R. F. B.}
}
@article {3347,
	title = {SNR ENHANCEMENT AND DECONVOLUTION OF RAMAN-SPECTRA USING A 2-POINT ENTROPY REGULARIZATION METHOD},
	journal = {Applied Spectroscopy},
	volume = {49},
	number = {4},
	year = {1995},
	note = {ISI Document Delivery No.: QV637Times Cited: 24Cited Reference Count: 20},
	month = {Apr},
	pages = {425-431},
	type = {Article},
	abstract = {A new method for Raman signal recovery, the two-point maximum entropy method (TPMEM), based on a regularization method using two-point entropy is presented, The method can be used for signal-to-noise ratio (SNR) enhancement in very low SNR measurements or for deconvolution, in order to remove the effects of the instrumental line shape on the measured spectrum, Unlike most SNR enhancement schemes, TPMEM requires no filter parameters and no a priori knowledge of the expected signal. A rigorous test on a randomly produced set of convolved and/or noise-corrupted simulated Raman spectra is presented in order to validate the method and compare it to Savitzky-Golay filtering and the maximum entropy method. The method is evaluated on the basis of the root mean square (rms) error and correlation coefficients of the recovered data with the original data, as well as on the basis of SNR improvement, and showed significant improvements in both performance and speed over conventional methods. The method is demonstrated in an application involving fiber-optic-linked Raman and resonance Raman spectroscopy.},
	keywords = {DECONVOLUTION, FILTERS, NOISE FILTERING, Raman spectroscopy, SNR ENHANCEMENT, TO-NOISE RATIOS},
	isbn = {0003-7028},
	url = {<Go to ISI>://A1995QV63700005},
	author = {Greek, L. S. and Schulze, H. G. and Blades, M. W. and Bree, A. V. and Gorzalka, B. B. and Turner, R. F. B.}
}
