Skin tone on mobile displays under different ambient lighting

2020 ◽  
Vol 2020 (1) ◽  
pp. 10-14
Author(s):  
Mingkai Cao ◽  
Ming Ronnier Luo
Keyword(s):  
Skin Tone ◽  
Chromatic Adaptation ◽  
Dark Condition ◽  
Mean Values ◽  
Colour Temperature ◽  
Capture Region ◽  
Ambient Lighting ◽  
Temperature Levels ◽  
Facial Images ◽  
Good Agreement

This experiment was aimed to study the preference of mobile phone facial images captured under different simulated ambient lightings. The experiment was carried out by assessing the preference of images for two facial images under 11 lightings (5 correlated colour temperature levels at 2 illuminances plus a dark condition). Forty-five images were processed via CAT02 chromatic adaptation transform to simulate the pictures captured under different light environments. The results revealed that the preferred capture region was between 6500 and 8000K around -0.05 Duv. Furthermore, it was found that the preferred skin tones of all the 45 rendered had good agreement under all the ambient lightings of viewing, i.e.to have mean values of L*, Cab*, hab of [76.3 25.1, 46.4°] units under D65/10 o conditions.

scholarly journals Preferred skin tones reproduction of three ethnic groups under different ambient lighting conditions

2020 ◽  
Vol 2020 (28) ◽  
pp. 94-99
Author(s):  
Mingkai Cao ◽  
Ming Ronnier Luo ◽  
Guoxiang Liu
Keyword(s):  
Ethnic Groups ◽  
Large Scale ◽  
Skin Tone ◽  
Chromatic Adaptation ◽  
Lighting Conditions ◽  
Ambient Lighting ◽  
Predicted Probability ◽  
Hue Angle ◽  
Scale Experiment ◽  
Facial Images

A large-scale experiment was conducted to investigate facial image quality on mobile phones. There were 8 original facial images from 4 skin tone types, each included a male and a female image. Each image was captured at 6500K and they were rendered to have 5 CCT (correlated colour temperature) and 5 Duv (the shifts away from the Blackbody locus) levels via CAT02 chromatic adaptation transform to simulate the effect of the images captured under 25 different lighting conditions. Each image was assessed under 9 ambient lighting conditions( including one dark condition) by 90 observers from 3 ethnic groups (Caucasian, Chinese and South Asian), each 30 observers. Preferred facial skin tone ellipse was established by maximizing the correlation coefficient between the model predicted probability and the preference percentage from the visual results. Four types of preferred skin tones had small differences in hue angle and chroma, but concentrated into a small colour region, about [24.7, 46.1°] for Cab* and hab values respectively. All ethnic group preferred images taken under illuminants having high CCT (6500-8000 K). It was also found that the chroma of the preferred skin tones will slightly increase as the ambient lighting CCT decrease.

Report of Ad Hoc Committee on Vitamin D Methodology, AOAC

1975 ◽  
Vol 58 (2) ◽  
pp. 330-332
Author(s):  
Forrest W Quackenbush ◽  
Daniel Banes ◽  
Philip H Derse
Keyword(s):  
Maleic Anhydride ◽  
Chemical Method ◽  
Ad Hoc ◽  
Collaborative Study ◽  
Mean Values ◽  
Biological Tests ◽  
Aoac Official ◽  
The Mean ◽  
Biological Methods ◽  
Good Agreement

Abstract In a collaborative study 6 samples of vitamin D3 resins were analyzed chemically by 9 laboratories and tested biologically by 3 laboratories to determine whether there exists a discrepancy between chemical and biological methods of measuring potency of these materials. The chemical methods employed saponification with and without subsequent maleic anhydride treatment. The biological method was the AOAC official final action rat assay, 39.149–39.162. The results showed good agreement between laboratories in the chemical analysis and relatively poor agreement in the biological tests. However, based upon the mean values as reported by the different laboratories, the chemical method employing saponification alone consistently overestimated biopotency, whereas the chemical method including maleic anhydride treatment gave results which averaged much closer to the mean biopotency values. There was no evidence that maleic anhydride treatment reduced values significantly below biopotency values.

scholarly journals Intellectual productivity under task ambient lighting

2016 ◽  
Vol 50 (2) ◽  
pp. 237-252 ◽  
Author(s):  
H Ishii ◽  
H Kanagawa ◽  
Y Shimamura ◽  
K Uchiyama ◽  
K Miyagi ◽  
...  
Keyword(s):  
Objective Evaluation ◽  
Average Concentration ◽  
Cognitive Tasks ◽  
Colour Temperature ◽  
Time Ratio ◽  
Lighting Conditions ◽  
Concentration Time ◽  
Ambient Lighting ◽  
Normal Colour ◽  
Intellectual Productivity

An experiment was conducted to evaluate intellectual productivity in three lighting conditions: (a) conventional ambient lighting, (b) task ambient lighting with normal colour temperature (5000 K) and (c) task ambient lighting with high colour temperature (6200 K). In the experiment, cognitive tasks were given to 24 participants. The concentration time ratio, which is a quantitative and objective evaluation index of the degree of concentration, was measured. The results showed that the average concentration time ratio under the task ambient lighting with high colour temperature was 72.5%, which was 5.0% points higher than that under the conventional ambient lighting. It is believed that intellectual work can be performed better when the concentration time ratio is high.

scholarly journals Energy-dispersive spectroscopy for the quantitative determination of the major chemical elements in milk

2021 ◽  
Vol 10 (10) ◽  
pp. e280101018910
Author(s):  
Igor Lima de Paula ◽  
Isis Rodrigues Toledo Renhe ◽  
Rodrigo Stephani ◽  
Ítalo Tuler Perrone ◽  
Antônio Fernandes de Carvalho ◽  
...  
Keyword(s):  
Quantitative Determination ◽  
Chemical Elements ◽  
Raw Milk ◽  
Energy Dispersive ◽  
Mean Values ◽  
Milk Samples ◽  
Application Potential ◽  
Major Chemical ◽  
Good Agreement

The present preliminary study aims at the rapid quantitative determination of the major chemical elements in the ashes of raw milk samples, using energy dispersive X-ray fluorescence spectrometry. The precision of the method was satisfactory (variation coefficient ≤ 5%). The mean values (in mmol·kg-1) obtained from the analysis of 32 raw milk samples showed good agreement with data from the Brazilian and international literature: K (26.1 ± 4.6), Ca (33.8 ± 3.7), P (28.4 ± 2.7), Na (21 ± 3.3) and Mg (4.7 ± 0.5). Residual Cl concentration (19.0 ± 3.3 mmol·kg-1) was lower than expected due to incineration losses. The results suggest a good application potential of the method for other dairy products.

Simulation of Oxy–Fuel Combustion of Heavy Oil Fuel in a Model Furnace

2015 ◽  
Vol 137 (3) ◽  
Author(s):  
Rached Ben-Manosur ◽  
Pervez Ahmed ◽  
M. A. Habib
Keyword(s):  
Heavy Oil ◽  
Liquid Fuel ◽  
Present Model ◽  
Soot Formation ◽  
Liquid Fuels ◽  
Oxyfuel Combustion ◽  
Temperature Levels ◽  
Oil Fuel ◽  
Probability Density Function Pdf ◽  
Good Agreement

The present study aims at investigating the characteristics of oxy-combustion of heavy oil liquid fuel in a down-fired model furnace. Nonpremixed probability density function (PDF) mixture model was used to simulate the combustion characteristics and turbulence chemistry. The validation of the present model was performed against the experimental data and is found to be in good agreement. The results depict that the oxy-combustion of liquid fuels results in lower soot. It is observed that the soot formation is reduced when N2 in air-combustion is replaced by O2 in oxy-combustion. However, it increases as the amount of oxygen in oxy-combustion increases. Replacing nitrogen in the air-combustion by carbon dioxide in oxyfuel combustion tends to reduce the temperature levels in the upstream sections of the combustion chamber.

Influence of Mix Proportions on Water Absorption of RCA Concretes

2016 ◽  
Vol 722 ◽  
pp. 187-194
Author(s):  
Roman Jaskulski ◽  
Paweł Las ◽  
Wojciech Kubissa
Keyword(s):  
Water Absorption ◽  
Probabilistic Models ◽  
Recycled Aggregate ◽  
Test Results ◽  
Mean Values ◽  
Concrete Mixtures ◽  
The Subject ◽  
The Mean ◽  
Best Fit ◽  
Good Agreement

The subject of the work is to develop probabilistic models defining the water absorption of concretes made ​​with the use of recycled aggregate (RCA). For the study 16 series of concrete mixtures were made with a 50 mass% share of recycled aggregate in the whole amount of coarse aggregate. The analysis of test results aimed at formulating a relationship between water absorption value and selected parameters of the composition of concretes. The objective was to find a model giving the best fit between calculated values and test results. Formulated models were then used in probabilistic modeling absorption using a Monte Carlo simulation. The results indicate a good agreement of the mean values of water absorption and possibility of good fitting of the standard deviation if an additional summand is introduced into the model.

Computational Fluid Dynamics Modeling of Impinging Gas-Jet Systems: I. Assessment of Eddy Viscosity Models

2005 ◽  
Vol 127 (4) ◽  
pp. 691-703 ◽  
Author(s):  
M. Coussirat ◽  
J. van Beeck ◽  
M. Mestres ◽  
E. Egusguiza ◽  
J.-M. Buchlin ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Nusselt Number ◽  
Eddy Viscosity ◽  
Gas Jet ◽  
Dynamics Modeling ◽  
Computational Fluid Dynamics Modeling ◽  
Mean Values ◽  
Viscosity Models ◽  
Good Agreement

Computational fluid dynamics plays an important role in engineering design. To gain insight into solving problems involving complex industrial flows, such as impinging gas-jet systems (IJS), an evaluation of several eddy viscosity models, applied to these IJS has been made. Good agreement with experimental mean values for the field velocities and Nusselt number was obtained, but velocity fluctuations and local values of Nusselt number along the wall disagree with the experiments in some cases. Experiments show a clear relation between the nozzle-to-plate distance and the Nusselt number at the stagnation point. Those trends were only reproduced by some of the numerical experiments. The conclusions of this study are useful in the field of heat transfer predictions in industrial IJS devices, and therefore for its design.

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