scholarly journals Application of the Entropy Method and Color Difference Formula to the Evaluation of Round Brilliant Cut Diamond Scintillation

Mathematics ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 1489
Author(s):  
Fukang Liu ◽  
Ying Guo ◽  
Shaojie Lv ◽  
Guange Chen

A modeling approach combining the entropy method and color difference formula is proposed in order to quantitatively evaluate diamond scintillation. The images of 66 diamonds were captured from 0° to 105° rotation at 15° intervals. The color difference of corresponding pixels in adjacent rotation angle images was calculated using a MatLab r2014a program, which indicated the diamond’s color change due to its scintillation. A threshold (10) was determined to divide the color difference into seven color difference intervals, the percentage of which indicated the color-change area. The color difference and the percentage were comprehensively analyzed using the entropy method to evaluate diamond scintillation objectively and quantitatively. Lightness was the main factor affecting the diamond scintillation while chroma and hue also significantly affected it.

2011 ◽  
Vol 474-476 ◽  
pp. 1638-1642 ◽  
Author(s):  
Hong Xia Zhao ◽  
Zhi Yang Luo ◽  
Xin Yuan ◽  
Yuan Li

The bad degree of meat and the color change have a close relation. Computer vision is not under the influence of physiological and psychological factor of person; Appraisement standard is objective and steady. Therefore, computer vision system has been established, which can do collection, management, display, and appraisement of porky color. The CIEL*a*b* and CIEDE2000 color difference formula were introduced into the classification of pork, the result was identical. Because the calculation course of CIEDE2000 color difference is complex, so the CIE1976L*a*b* color difference is still adopted to calculate color change at actual production.


Author(s):  
Işıl Sarıkaya ◽  
Hande Dilli

Purpose: The aim of this study was to compare the color stability of two different hybrid ceramic materials. Materials & Methods: Using the precision cutting device (Micracut, Metcon, Turkey), 36 specimens (12 x 15 x 1 mm) were obtained from Vita Enamic (Vita Zahnfabrik, Germany) and Lava Ultimate (3M ESPE, St.Paul, USA) CAD / CAM blocks. After finishing procedures were completed, all specimens were stored in distilled water for 24 h. Then, the specimens were dried and the initial color measurements were made. L, a, b values were determined using a spectrophotometer (Vita Easy Shade, Vita Zahnfabrik, Germany). The specimens were then divided into 3 test groups and stored in coffee (Nescafe Classic, Turkey) (G2, G5), energy drink (Red Bull, Austria) (G3, G6), and in the distilled water as the control group (G1, G4), for 48 h. After 48 h, the specimens were washed with distilled water and dried. Second color measurements were made. ∆E00 values were calculated using the CIEDE 2000 color-difference formula. Results: Data were analyzed by two-way ANOVA. Multiple comparisons were made with Bonferroni’s test. There was a statistically significant difference between 2 ceramics (p=0.035). Generally, Lava Ultimate showed more color change than Vita Enamic. Among the beverages, coffee was significantly different for both ceramics than control and energy drink (p<0.05). Conclusion: Lava Ultimate, showed more color change than Vita Enamic. Coffee has also been determined as the most colorant drink for both hybrid ceramics.


2009 ◽  
Vol 29 (2) ◽  
pp. 465-467
Author(s):  
Zhen-ya YANG ◽  
Yong WANG ◽  
Zhen-dong YANG ◽  
Cheng-dao WANG

2012 ◽  
Vol 531-532 ◽  
pp. 54-57 ◽  
Author(s):  
Li Ping Tong ◽  
Bin Peng ◽  
Yi Wei Fei ◽  
Hong Wei Yang

In order to eliminate the human eyes’ subjective differences in the level recognition of the jet fuel’s silver corrosion, chromatic aberration system is used to calculate chromatic aberration between the image of the standard colorimetric board and the experiment silver corrosion. By contrast, this paper chooses the least chromatic aberration to estimate the level of silver corrosion. The CIEDE2000 of the color difference formula, which can match with person vision theoretically, is applied in the chromatic aberration system at present, and can reflect the minor differences in color correctly. so this paper attempts to use CIEDE2000 color formula to determine the silver strip corrosion, which can reduce the influence of professionals’ subjective factors, and these results are more objective and accurate, which proves the actual feasibility of this method.


2014 ◽  
Vol 11 (2) ◽  
pp. 107-110
Author(s):  
Mushtaq Mangat ◽  
A. Abbasi ◽  
Jakub Wiener

Traditional denim made by using 100% cotton and novel denim made by using cotton in warp and spun PP in the weft were treated in 11 different ways on industrial garment washing machines with the help of various textile auxiliaries and pumice. There is an obvious change in color of denim. This change was measured by using Spectrophotometer. Reflectance was taken as a variable to observe the intensity of change. Color difference was measured by using the CIELab color difference formula 1976. Color space coordinates (L*, a*, b*) and color difference ΔE were calculated between the untreated denim and treated denim.


1968 ◽  
Vol 14 (1) ◽  
pp. 25-31 ◽  
Author(s):  
G. W. Strandberg ◽  
P. W. Wilson

The formation and activity of nitrogenase2 in Azotobacter vinelandii OP was examined using a cell-free assay system. A lag period of about 30 min occurred between the exhaustion of the combined nitrogen source and growth on N2. Cells grown on ammonium acetate or potassium nitrate had no detectable nitrogenase activity. Nitrogenase activity appeared in cells, grown under a flowing gas phase of 20% O2 – 60% He, about 45 min after the exhaustion of ammonia. Nitrogenase formation was inhibited in a closed system with an atmosphere containing 40% O2 but not by one containing 20% O2. Hydrogen did not inhibit enzyme formation. The question of whether N2 is required for the formation of the enzyme could not be answered as this gas could not be completely eliminated from the growth system. Chloramphenicol prevented the formation of the enzyme and inhibited nitrogen fixation in whole cells, but had no effect on cell-free enzyme activity. A brief rise in turbidity which occurred during nitrogenase formation appeared to be due to a color change in the cells from reddish brown to dark brown. Spectrophotometric examination of extracts from ammonia- and N2-grown cells did not reveal any components responsible for this color difference, but this result may reflect only the presence of interfering substances in the crude extract.


2012 ◽  
Vol 200 ◽  
pp. 637-640
Author(s):  
Jing Liang ◽  
Yong Bin Zhao ◽  
Hui Gao

The iCAM (image color appearance model) as the most advanced modern color appearance model is constantly being put into use. In color images industry, the evaluation of the color difference is significant. This article will focus on color difference formula of image color appearance model and analysis its reasonable color difference calculation method, which reflects the advantages of image color appearance model.


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