%0 Journal Article
%T Absorption spectrophotometry signal de-noising using invariant wavelets Filtrado de se ales en espectrofotometr赤a de absorci車n mediante wavelets invariantes a la traslaci車n
%A Vargas Caˋas Rubiel
%A Loaiza Correa Humberto
%J Ingenier赤a e Investigaci車n
%D 2011
%I Universidad Nacional de Colombia
%X Diseases such as cancer, hepatitis and AIDS cause body fluid concentration and amount to become modified; their measurement can thus be useful as a diagnostic technique. Spectroscopy is one of the most widely used techniques for biological substance detection and quantification. The presence of unwanted signals is the main limiting factor for sensitivity and quality; this is called noise. Noise has different backgrounds which range from physical assumptions to environmental influence. Eliminating or reducing noise in spectroscopy has thus been studied for many years and the applicability of wavelet transform has been demonstrated in recent decades. This paper presents invariant wavelet transform for increasing signal to noise ratio in spectrophotometer signals and thus improve the quality of spectrophotometric analysis and biological substance quantification. The proposed technique was applied to artificially-generated signals and signals from two spectrometers, one having a continuum source and another with a laser radiation source. The results obtained with this technique were compared to those obtained from traditional filters: Gaussian, Wiener and orthogonal wavelets. This technique＊s main advantages are a substantial increase in signal to noise ratio and preservation of spectral peak location and width. These advantages increase biological substance detection and quantification quality and accuracy and allow automatic analysis of the spectrum. They can also lead to better understanding of experimental limitations and allow a quantitative study of the influence of changes in substance concentration in related diseases. Enfermedades como c芍ncer, hepatitis y sida, entre otras, ocasionan que la concentraci車n y cantidad de algunas sustancias en fluidos corporales se modifique, por lo que su medici車n puede servir como t谷cnica diagn車stica. Entre las t谷cnicas m芍s utilizadas para la detecci車n y cuantificaci車n de sustancias biol車gicas se encuentra la espectroscop赤a. El principal factor que limita la sensibilidad y calidad en la medida es la presencia de se ales indeseadas, denominadas ruido. El ruido tiene diferentes or赤genes, los cuales van desde los supuestos f赤sicos hasta la influencia ambiental. Eliminar o reducir el ruido en espectroscop赤a ha sido objeto de estudio durante muchos a os y en los 迆ltimos lustros se ha demostrado la aplicabilidad de la transformada wavelet con dicho prop車sito. Este trabajo presenta una transformada wavelet invariante a la traslaci車n como una alternativa para aumentar la relaci車n se al a ruido en se ales provenientes de espec
%K espectrofotometr赤a de absorci車n
%K filtrado de se ales
%K wavelets invariantes a la traslaci車n
%K detecci車n de sustancias biol車gicas
%U http://www.revistas.unal.edu.co/index.php/ingeinv/article/view/26412