scholarly journals A Comparison of Two Different Light Booths for Measuring Color Difference of Metameric Pairs

Textiles ◽  
2021 ◽  
Vol 1 (3) ◽  
pp. 558-570
Author(s):  
Azmary Akter Mukthy ◽  
Michal Vik ◽  
Martina Viková
Keyword(s):  
Textile Industry ◽  
Visual Assessment ◽  
Color Difference ◽  
Color Appearance ◽  
Light Sources ◽  
Visual Color ◽  
Close Relationship ◽  
Appearance Models ◽  
The Right ◽  
Tungsten Lamp

A standardized source of light is essential for visual color assessments, which is why lighting booths were developed. For the best results in visual assessment, it is important to consider the right choice of light source, the right viewing conditions, and the variability of the viewer. To date, many light booth technologies have been introduced to meet user demands. Since most of the light sources on the market are characterized by the designer or manufacturer, the resulting variations from booth-to-booth remain. In this study, we compared the performance of two standard light booths to assess the color difference of eleven metameric pairs. In this study, we checked an earlier technology-based light booth that is still used in the textile industry and contains illuminant A (Tungsten lamp) with CCT 2700 K, TL84 (tri-band fluorescent tube) with CCT 4000 K, and simulator D65 (CCT 6500 K) with a different light booth whose original light sources have been replaced by currently available LED retro kits from equivalent CCTs. As an inexperienced customer or industrial user, our question was, how important is this replacement? The results revealed that two different standard lighting technologies with similar CCTs cannot reproduce the same estimates because the light sources produced different SPDs. It is illustrating that caution is necessary when comparing results obtained from two different light booths containing light sources with similar CCTs but different SPDs. This comparative study suggested that the variability of the light sources’ SPDs or the observer or the sample should be modeled considering light booth’s technology to estimate its contribution to the overall variability. The close relationship between perceived and CAM02-UCS suggests that if both booths are used after the light sources have been calibrated, a formula based on color appearance models must be used to predict color appearance. To obtain better agreement between perceived and calculated color difference, one must need to avoid light booths with nominally white light sources.

A Digital Test Chart for Visual Assessment of Color Appearance Scales

2021 ◽  
Vol 2021 (29) ◽  
pp. 160-165
Author(s):  
Mark D. Fairchild
Keyword(s):  
Human Perception ◽  
Visual Assessment ◽  
Model Testing ◽  
Color Appearance ◽  
Psychophysical Data ◽  
Appearance Models ◽  
Digital Test ◽  
Computational Comparison

A digital color appearance test chart, akin to a ColorChecker® Chart for human perception, was developed and evaluated both perceptually and computationally. The chart allows an observer to adjust the appearance of a limited number of color patches to allow a quick evaluation of perceived brightness, colorfulness, lightness, saturation, and hue on a display. The resulting data can then be used to compared observed results with the predictions of various color appearance models. Analyses in this paper highlight some known shortcomings of CIELAB, CIECAM02, and CAM16. Differences between CIECAM02 and CAM16 are also highlighted. This paper does not provide new psychophysical data for model testing, it simply describes a technique to generate such data and a computational comparison of models.

Evaluation Accepted Small Color-Difference Samples by Using High Glossy Ink-Jet Paper

2011 ◽  
Vol 380 ◽  
pp. 179-182
Author(s):  
Jing Liang ◽  
Ning Fang Liao ◽  
Yu Sheng Lian ◽  
Yuan Yuan Wang
Keyword(s):  
Color Vision ◽  
Color Space ◽  
Visual Assessment ◽  
Color Difference ◽  
Normal Color Vision ◽  
Visual Color ◽  
Difference Formula ◽  
Ink Jet ◽  
Human Color Vision ◽  
High Range

In order to study the human color vision characteristics, the small color-difference discrimination threshold experiment at the 17 basic CIE color centers of high range of gloss color printed samples. A panel of 10 observers with normal color vision performed the visual assessment to 510 pairs of samples using admissibility method. The evaluation data of visual color-difference were obtained in CIELAB color space. The detailed comparision indicated that the data were used evaluate the four common color-difference formula, CIELAB, CIE94, CMC and CIEDE2000. The detailed analysis indicated that CIELAB recommended by CIE Performanced the best among the four modern color difference. For predicting very small color datas. The experimental data provides references for the improvement of uniform color space and color-difference formula.

Change of color appearance due to extremely high light level: corresponding colors under 100 and 3000 cd/m2

2019 ◽  
Vol 2019 (1) ◽  
pp. 320-325 ◽  
Author(s):  
Wenyu Bao ◽  
Minchen Wei
Keyword(s):  
Light Level ◽  
Limited Range ◽  
High Light ◽  
Color Preference ◽  
Color Appearance ◽  
Appearance Model ◽  
Color Matching ◽  
Light Levels ◽  
Appearance Models ◽  
Psychophysical Study

Great efforts have been made to develop color appearance models to predict color appearance of stimuli under various viewing conditions. CIECAM02, the most widely used color appearance model, and many other color appearance models were all developed based on corresponding color datasets, including LUTCHI data. Though the effect of adapting light level on color appearance, which is known as "Hunt Effect", is well known, most of the corresponding color datasets were collected within a limited range of light levels (i.e., below 700 cd/m2), which was much lower than that under daylight. A recent study investigating color preference of an artwork under various light levels from 20 to 15000 lx suggested that the existing color appearance models may not accurately characterize the color appearance of stimuli under extremely high light levels, based on the assumption that the same preference judgements were due to the same color appearance. This article reports a psychophysical study, which was designed to directly collect corresponding colors under two light levels— 100 and 3000 cd/m2 (i.e., ≈ 314 and 9420 lx). Human observers completed haploscopic color matching for four color stimuli (i.e., red, green, blue, and yellow) under the two light levels at 2700 or 6500 K. Though the Hunt Effect was supported by the results, CIECAM02 was found to have large errors under the extremely high light levels, especially when the CCT was low.

Color Difference Evaluation Based on Image Color Appearance Model

2012 ◽  
Vol 200 ◽  
pp. 637-640
Author(s):  
Jing Liang ◽  
Yong Bin Zhao ◽  
Hui Gao
Keyword(s):  
Calculation Method ◽  
Color Difference ◽  
Color Images ◽  
Color Appearance ◽  
Appearance Model ◽  
Difference Formula ◽  
Difference Calculation

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.

Systems Biology Technologies Enable Personalized Traditional Chinese Medicine: A Systematic Review

2012 ◽  
Vol 40 (06) ◽  
pp. 1109-1122 ◽  
Author(s):  
Xijun Wang ◽  
Aihua Zhang ◽  
Hui Sun ◽  
Ping Wang
Keyword(s):  
Systems Biology ◽  
Chinese Medicine ◽  
Traditional Chinese Medicine ◽  
Disease Diagnosis ◽  
Modern Medicine ◽  
Therapeutic Approaches ◽  
Current Trends ◽  
Close Relationship ◽  
The Right ◽  
Personalize Medicine

Traditional Chinese medicine (TCM), an alternative medicine, focuses on the treatment of human disease via the integrity of the close relationship between body and syndrome analysis. It remains a form of primary care in most Asian countries and its characteristics showcase the great advantages of personalized medicine. Although this approach to disease diagnosis, prognosis and treatment has served the medical establishment well for thousands of years, it has serious shortcomings in the era of modern medicine that stem from its reliance on reductionist principles of experimentation and analysis. In this way, systems biology offers the potential to personalize medicine, facilitating the provision of the right care to the right patient at the right time. We expect that systems biology will have a major impact on future personalized therapeutic approaches which herald the future of medicine. Here we summarize current trends and critically review the potential limitations and future prospects of such treatments. Some characteristic examples are presented to highlight the application of this groundbreaking platform to personalized TCM as well as some of the necessary milestones for moving systems biology of a state-of-the-art nature into mainstream health care.

Geometric morphometric analysis of different species of Cyprideis deriving from the Early Pleistocene record of Greece.

2021 ◽  
Author(s):  
Ypermachia Dimitriou ◽  
Penelope Papadopoulou ◽  
Maria Kolendrianou ◽  
Maria Tsoni ◽  
George Iliopoulos
Keyword(s):  
Endemic Species ◽  
Early Pleistocene ◽  
Geometric Morphometric ◽  
Representative Species ◽  
Lower Pleistocene ◽  
Close Relationship ◽  
Outline Analysis ◽  
Geometric Morphometric Analysis ◽  
The Right ◽  
Of Greece

<p>The genus Cyprideis is one of the most widespread ostracod representative of the Pleistocene brackish palaeoenvironments. Especially <em>Cyprideis torosa </em>is often found in great numbers and even in monospecific taphocoenoses and for this reason its study is very useful for palaeoenvironmental reconstructions.  The identification of different species of Cyprideis is often complicated and needs careful morphology inspection. This becomes even more difficult in the case of endemic species which present significant similarities with each other.  In this work, we have studied and analyzed several  Cyprideis species (<em>C.torosa, C. frydaci, C.dictyoti, C. pannonica, C. elisabeta, C. seminulum, C. heterostigma</em>) deriving from brackish palaeoenvironments of a Lower Pleistocene marl sequence in Sousaki Basin (Northeastern Corinth Graben, Greece). More specifically size measurements and geometric morphometrics (lateral valve outline of both right and left valves as well as females and males) were used in order to attest the similarities and dissimilarities between the different species and draw conclusions about their origin.  According to the valve outline and the multivariate analysis a close relationship between the valve shape of all Cyprideis species can be noticed. <em>C. torosa</em> is commonly grouped with <em>C. pannonica</em> except in the male right valve where the two species show some differences.  The endemic species <em>C. frydaci</em> and <em>C. dictyoti</em> can be identified by the differences in the right valve of the male and female respectively.  The other species could not be substantially differentiated using just the outline analysis which possibly denotes their common genetic origin.  The valve outline has proved to be a very useful character for recognizing the different species especially when the two valves of both females and males are considered. More analyses of representative species of Miocene and Pliocene Cyprideis are needed in order to establish their phylogenetic relationships and draw conclusions about their common ancestor.</p>

Morphological signs of neurogenic inflammation in the heart of rats during aging

2022 ◽  
pp. 831-840
Author(s):  
Е.И. Чумасов ◽  
Е.С. Петрова ◽  
Д.Э. Коржевский
Keyword(s):  
Neurogenic Inflammation ◽  
Plasma Cells ◽  
Nerve Fibers ◽  
Blood Capillaries ◽  
Pgp 9.5 ◽  
Sympathetic Nerve Fibers ◽  
Close Relationship ◽  
The Right ◽  
Inflammatory Infiltrates ◽  
Heart Apparatus

С помощью гистологических методов окраски толуидиновым синим, гематоксилином и эозином и иммуногистохимических реакций на белок PGP 9.5, тирозингидроксилазу (ТГ), белок Iba-1, изучены клеточные изменения в разных отделах сердца крыс линии Wistar в возрасте 18- 23 мес. В соединительной ткани основания сердца обнаружены очаговые воспалительные инфильтраты, внутри которых выявлены PGP 9.5 и ТГ сплетения, состоящие из парасимпатических и симпатических нервных волокон. В области клапанного аппарата, на границе фиброзного кольца и миокарда правого предсердия, обнаружены патологические изменения нервных структур - дегенерация нервных пучков и зернистый распад варикозных аксонов терминального сплетения. Установлены тесные взаимоотношения аксонов терминальной нервной сети с клетками воспалительных инфильтратов и кровеносными сосудами. Определены закономерности встречаемости в различных отделах миокарда у старых животных нейроклеточных воспалительных комплексов, состоящих из нервных волокон, кровеносных капилляров и клеток-участников местного воспалительного процесса (тучных клеток, макрофагов, фибробластов, плазмоцитов). Установлен хронический характер нейрогенного воспаления в сердце при старении. Using histological methods of staining with toluidine blue, hematoxylin-eosin and immunohistochemical reactions for the PGP 9,5 protein, tyrosine hydroxylase (TH), Iba-1 protein, cellular changes in different parts of the heart of Wistar rats at the age of 18-23 months were studied. In the connective tissue of the heart base, focal inflammatory infiltrates were found, near which PGP 9.5 and TH plexuses, consisting of parasympathetic and sympathetic nerve fibers, were detected. In the area of the valvular heart apparatus, at the border of the anneau fibreux and the myocardium of the right atrium, pathological changes in nerve structures were found: degeneration of nerve fibers and granular destruction varicose axons of the terminal plexus. A close relationship has been established between axons of the terminal nervous network and cells of inflammatory infiltrates and blood capillaries. The features of the localization of neurocellular inflammatory complexes consisting of nerve fibers, blood capillaries and cells participating in the local inflammatory process (mast cells, histiocytes, monocytes, fibroblasts, plasma cells) in various parts of the myocardium in old animals are described. The chronic nature of neurogenic inflammation in the heart during aging has been established.

Partial Color Constancy of Isolated Surface Colors Examined by a Color-Naming Method

Perception ◽  
1989 ◽  
Vol 18 (1) ◽  
pp. 83-91 ◽  
Author(s):  
Keiji Uchikawa ◽  
Hiromi Uchikawa ◽  
Robert M Boynton
Keyword(s):  
Color Constancy ◽  
Color Naming ◽  
The State ◽  
Color Appearance ◽  
Chromatic Adaptation ◽  
Light Sources ◽  
Two Factors ◽  
The Subject ◽  
Spectral Distributions ◽  
Color Scales

Color samples selected from the OSA Uniform Color Scales set were viewed without any surround. Separate light sources were used to illuminate the samples and to control the state of adaptation of the subject, thereby separating two factors that are normally confounded. A color-naming procedure was used to assess shifts in color appearance produced by altering the spectral distributions of one or both light sources. The results confirm that chromatic adaptation, when it is the only factor operating, can mediate partial color constancy.

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