Merit function for the evaluation of color uniformity in the far field of LED spot lights

The scope of the present paper is the derivation of a merit function which predicts the visual perception of LED spot lights. The color uniformity level Usl is described by a linear regression function of the spatial color distribution in the far field. Hereby, the function is derived from four basic functions. They describe the color uniformity of spot lights through different features. The result is a reliable prediction for the perceived color uniformity in spot lights. A human factor experiment was performed to evaluate the visual preferences for colors and patterns. A perceived rank order was derived from the subjects’ answers and compared with the four basic functions. The correlation between the perceived rank order and the basic functions was calculated resulting in the definition of the merit function Usl. The application of this function is shown by a comparison of visual evaluations and measurements of LED retrofit spot lamps. The results enable a prediction of color uniformity levels of simulations and measurements concerning the visual perception. The function provides a possibility to evaluate the far field of spot lights without individual subjective judgment. © (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

Adaptive evolution of color vision of the Comoran coelacanth (Latimeria chalumnae)

The coelacanth, a “living fossil,” lives near the coast of the Comoros archipelago in the Indian Ocean. Living at a depth of about 200 m, the Comoran coelacanth receives only a narrow range of light, at about 480 nm. To detect the entire range of “color” at this depth, the coelacanth appears to use only two closely related paralogous RH1 and RH2 visual pigments with the optimum light sensitivities (λmax) at 478 nm and 485 nm, respectively. The λmax values are shifted about 20 nm toward blue compared with those of the corresponding orthologous pigments. Mutagenesis experiments show that each of these coadapted changes is fully explained by two amino acid replacements.

Parallel detection of violations of color constancy

The perceived colors of reflecting surfaces generally remain stable despite changes in the spectrum of the illuminating light. This color constancy can be measured operationally by asking observers to distinguish illuminant changes on a scene from changes in the reflecting properties of the surfaces comprising it. It is shown here that during fast illuminant changes, simultaneous changes in spectral reflectance of one or more surfaces in an array of other surfaces can be readily detected almost independent of the numbers of surfaces, suggesting a preattentive, spatially parallel process. This process, which is perfect over a spatial window delimited by the anatomical fovea, may form an early input to a multistage analysis of surface color, providing the visual system with information about a rapidly changing world in advance of the generation of a more elaborate and stable perceptual representation.

Effects of Institutional Factors on the Retention of Graduate Students of Color in Schools of Library and Information Science

The intent of the study was to understand the changes that have occurred over the last 25 years in library programs as far as enrollment and diversity of students, number and ethnicity of the faculty, program income and expenses, cost of attendance, and scholarship and fellowship aid, in an effort to better understand library programs granting the MLIS degree. The study also endeavored to identify institutional factors associated with the retention and productivity rates of White students and students of color in schools of library and information science. During the period studied, the proportional representation of White students decreased. For students of color, proportional representation was stable during the same time period. Results revealed a medium effect size of time with productivity rates for both groups declining over time. Retention rate differed significantly by time, with a small effect size with retention rate that initially increased over time, but is now decreasing. The final analyses were meta-regressions to determine if retention and productivity rates can be predicted by cost of attendance, scholarship and fellow aid, and program size. Results indicated that for students of color, program size in 2000 was significantly predictive of retention, cost of attendance was predictive in 2002, and scholarship and fellowship aid was predictive of retention in 2004. No variables were significantly predictive for retention of White students. The last analysis was to determine if productivity rate can be predicted by cost of attendance, scholarship and fellow aid, and program size. Results indicate that for White students in 2002, the cost of attendance was predictive of productivity rating. In 2003, scholarship and fellowship aid was predictive of productivity rate and in 2004, scholarship and fellowship aid was predictive of productivity rating. For students of color, results indicate that only scholarship and fellowship aid in 2005 was predictive of productivity rate. No other variables in any of the years studied showed any significant prediction of productivity rating for students of color.

The current challenges of Color Physics and Chemistry

Day of Chemistry, Invited conference, San Alberto Magno 2014

Voters and Candidates of the Future

Within the literature there is a growing concern about lower voter turnout rates among young age cohorts. In this article we investigate the reported willingness to vote among 72,466 14-year old adolescents from 22 European countries, taking part in the International Citizen and Civic Education Survey (ICCS, 2009). Results indicate that the willingness to vote remains quite high among this age group, but with a clear gender division. While girls are more likely to state that they will vote, boys are more likely to see themselves as a future election candidate. An open classroom climate at school contributes to the willingness to vote in future elections. The elements that are known to have an effect on the turnout level of adults, however, do not have a significant impact on the intention to vote among adolescents. This would suggest that the observed low turnout rate among young age groups cannot just be attributed to an alleged lack of political motivation among adolescents.

Voters and Candidates of the Future

Within the literature there is a growing concern about lower voter turnout rates among young age cohorts. In this article we investigate the reported willingness to vote among 72,466 14-year old adolescents from 22 European countries, taking part in the International Citizen and Civic Education Survey (ICCS, 2009). Results indicate that the willingness to vote remains quite high among this age group, but with a clear gender division. While girls are more likely to state that they will vote, boys are more likely to see themselves as a future election candidate. An open classroom climate at school contributes to the willingness to vote in future elections. The elements that are known to have an effect on the turnout level of adults, however, do not have a significant impact on the intention to vote among adolescents. This would suggest that the observed low turnout rate among young age groups cannot just be attributed to an alleged lack of political motivation among adolescents.

Color problems; a practical manual for the lay student of color,

Transparent screens in envelope.

Worlds of color.

Mode of access: Internet.

Vaughan's "Freedmen's pension bill." : being an appeal in behalf of men released from slavery : a plea for American freemen and a rational proposition to grant pensions to persons of color emancipated from slavery /

Mode of access: Internet.

Multicultural literature for children and young adults : a selected listing of books, 1980-1990, by and about people of color /

Includes index.

Color in everyday : a manual for lay students, artisans and artists on the principles of color combination and color arrangement, and their applications in dress, home, business, the theatre and community play /

"The book has grown out of a course of lectures on 'Color and its applications, based on a study of Museum originals' given at the Metropolitan Museum of Art under the auspices of New York University."--Introd.

The significance of color banding in the upper layers of Kara Sea sediments.

"CG 373-36."

Women of Color Forum : a collection of readings /

WI docs. no.: Ed.3/2:0404