The human color constancy uses spatial comparisons. The relationships among neighboring pixels are far more important than the absolute differences between the colorimetric values of an original and its gamut-limited reproduction. If all the pixels in an image have a reproduction error in the same direction (red, green, blue, lightness, hue, chroma), then our color constancy mechanism helps to ...

In this work we present different computational strategies for colorimetric characterization of scanners using multidimensional polynomials. The designed strategies allow us to determine the coefficients of an a priori fixed polynomial taking into account different color error statistics. Moreover, since there is no clear relationship between the polynomial chosen for the characterization and t...

QUANTITATIVE determinations of serum and urinary proteins are of considerable clinical importance; that such estimations are made relatively infrequently is probably due to the lack of a simple yet trustworthy technique. The methods of Esbach and Aufrecht are notoriously crude, while the gravimetric and the Kjeldahl methods are too laborious for ordinary clinical purposes. Of the colorimetric p...

The writers recently had occasion to use the picric acid colorimetric method (commonly called the Benedict-Lewis method) 2 for determining the sugars in cornstalk juices. Although it has been used mostly as a micro method for blood and urine analyses, it has been used to some extent as a macro method. {3* 5, 12.) It proved to be more rapid than, and approximately as accurate as a, copper reduct...

HE MOST FREQUENTLY USED procedure for the determination of free fatty acids (FFA) in body fluids or biologic media is that of Dole (4). This method is based on the extraction of fatty acids with organic solvents followed by titration with dilute alkali. Despite improvements in specificity (3, 5, 6), this method is subject to error resulting from dissolved atmospheric carbon dioxide. When applie...

In multispectral imaging system, one of the most important tasks is to accurately reconstruct the spectral reflectance from system responses. We propose such a new method by combing three most frequently used techniques, i.e., wiener estimation, pseudo-inverse, and finite-dimensional modeling. The weightings of these techniques are calculated by minimizing the combined standard deviation of bot...

a graphene oxide-terpyridine conjugate (gotc) based colorimetric and fluorescent nano-chemosensor was synthesized. it showed high selectivity and sensitivity for fe2+ and fe3+ ions in neutral aqueous solution over other metal ions such as li+, na+, ba2+, ca2+, al3+, cd2+, co2+, cu2+, hg2+, mn2+, ni2+, pb2+, zn2+, cr3+ and ag+. in absorption spectra, upon addition of fe2+ or fe3+, the sensor dis...

This paper compares CIE 2006 model predictions and the 1964 10° standard colorimetric observer with the average observer data from three distinct subgroups of 47 Stiles-Burch observers formed on the basis of observer ages. For two of these subgroups, the long-wave sensitive (x-) color matching functions obtained from the CIE 2006 model did not accurately predict the intra-group average observer...

Evidence is presented that the colorimetric chloranilate calcium method can be accurately applied to urine provided that elimination of interfering substances, which include magnesium, is performed prior to the determination. Isolation of calcium as the oxalate, followed by perchioric acid digestion, has been shown to be an acceptable method whereby urinary calcium can be put in a suitable stat...

Device independent color requires that all color imaging devices “speak” in CIE colorimetric terms. A color image scanner is one component of the desktop color imaging chain that needs to be colorimetric if color is to be device independent. Most commercial color scanners are not colorimetric. Instead, they are built as color densitometers, emulating commercial graphic arts scanners. There are ...