In contrast to the classical findings of lightness constancy, recent psychophysical studies show the strong dependency of the perceived reflectance of a surface on the structure of the natural illumination. The present study examined this inconstancy for systematic variations in the light field and an image-based explanation for it. Observers matched the specular and diffuse reflectance of a th...

Sequences from homologous regions of the nuclear and mitochondrial small-subunit rRNA genes from 10 members of the mushroom order Boletales were used to construct evolutionary trees and to compare the rates and modes of evolution. Trees constructed independently for each gene by parsimony and tested by bootstrap analysis have identical topologies in all statistically significant branches. Exami...

We investigate color constancy for real 2D paper samples using a successive matching paradigm in which the observer memorizes a reference surface color under neutral illumination and after a temporal interval selects a matching test surface under the same or different illumination. We find significant effects of the illumination, reference surface, and their interaction on the matching error. W...

A technique to retrieve images by region matching using a combined feature index based on color, shape, and location is presented within the framework of MPEG-7. Dominant regions within each image are indexed using integrated color, shape, and location features. Various combinations of regions are also indexed. The resulting indices and related metadata are stored in a Hash structure, where sim...

A fast, color-based algorithm for unknown illuminant is presented. of the object's color distribution R, G and B denote the 3 color 1: recognizing objects and textures viewed under an Objects are indexed by six numbers: the angles and the angles of the color edge distributions. If )ands of the image of an object (stretched out as vectors) then the color angular index comprises the 3 inter-band ...

The role of mutations of small versus large effect in adaptive evolution is of considerable interest to evolutionary biologists. The major evolutionary pathways for the origin of dioecy in plants (the gynodioecy and monoecy-paradioecy pathways) are often distinguished by the number of mutations involved and the magnitude of their effects. Here, we investigate the genetic and environmental deter...

doppler ultrasound can provide important information about vascular problems through the analysis of blood flow wave-form. the purpose of this study was obtaining the normal images of color doppler and estimation of blood flow velocity parameters of femoral artery in rabbits. left and right femoral arteries of 8 healthy adult new zealand rabbits were evaluated. color and spectral doppler images...

Background and Objectives: Solvents are widely used in industries. Occupational exposure to organic solvents can lead to dysfunction of the nervous system. Since color-vision impairment can be a sensitive and early marker of neurotoxic damage, this study was designed to determine the influence of chronic occupational exposure to organic solvent mixtures on color vision. Materials and Methods: ...