Measuring linear density of threads in single‐system‐mélange color fabrics with FCM algorithm

According to the color yarns in the fabric, the fabrics can be divided into three categories: solid color fabrics, single‐system‐mélange color fabrics, and double‐system‐mélange color fabrics. The density of solid fabrics can be inspected with gray‐projection method or Fourier analysis method. But the methods cannot be applied to yarn‐dyed fabrics directly. A method for detecting the density of single‐system‐mélange color fabrics will be discussed in this article. By analyzing the pattern and color characters of single‐system‐mélange color fabrics, fuzzy C‐means algorithm is proposed to classify the colors in the fabric image based on CIELAB color space first. With the color segmentation results, the fabric can be divided into different blocks. The yarns can be located in different blocks with different average gray‐levels, and then the number of yarns can be counted in each block. The linear density of threads can be obtained by counting the yarns in a unit length finally. The experiment proved that the algorithm proposed in this study can inspect the density of single‐system‐mélange color fabric successfully. © 2012 Wiley Periodicals, Inc. Col Res Appl, 38, 456–462, 2013     

The impact of closure type and storage conditions on the composition, colour and flavour properties of a Riesling and a wooded Chardonnay wine during five years' storage

This paper presents the results from an investigation to assess the development of a Riesling and a wooded Chardonnay wine over five years following the imposition of several treatments at bottling. The wines were bottled under a screw cap closure, two different natural corks, a synthetic closure and in a glass ampoule. In addition, the effect of storage orientation was investigated. The bottled wines were stored under controlled temperature and humidity conditions. Various analyses were carried out on replicate bottles from each treatment, including sulfur dioxide and ascorbic acid concentration, sensory analysis of appearance and aroma attributes, and spectral measures. The largest treatment effect resided with the nature of the closure. Wines sealed with the synthetic closure were relatively oxidised in aroma, brown in colour, and low in sulfur dioxide compared to wines held under the other closures. A struck flint/rubber ( reduced ) aroma was discernible in the wines sealed under the screw caps or in glass ampoules. Wines sealed under natural bark corks in this study showed negligible reduced characters. The bottle orientation during storage under the conditions of this study had little effect on the composition and sensory properties of the wines examined.     

An ultrahigh‐definition display using the pixel‐offset method

Abstract— An ultrahigh‐definition display system quadrupling the horizontal and vertical resolution of HDTV has been developed. In order to obtain the ultrahigh definition, four LCD panels (red, green 1, green 2, and blue) are combined using the spatial pixel‐offset method. Therefore, only green images have an ultrahigh resolution of 4096 × 7680 pixels, while red and blue images have 2048 × 3840 pixels. The ultrahigh resolution was confirmed by subjective assessment testing. The scores of the test have the same tendencies as the SQRI values. The necessary accuracy of the convergence correction is calculated to be within 0.3 pixels by the modified s‐CIELAB method.     

Are we able to distinguish color attributes?

The perception and understanding of the three color attributes have been analyzed from two experiments using pairs of Munsell samples, where only one of the three color attributes were changed/unchanged (Experiment I/II) at a time. In each experiment, 36 pairs with color differences of 3 different sizes (average values of 15.8 and 21.7 CIELAB units for Experiments I and II, respectively) were assessed under standardized conditions by 40 normal observers, 20 of them with previous knowledge and experience in colorimetry. At a 95% confidence level, the results from the two experiments were not significantly different, indicating that color attributes were not easily distinguished: for example, for experienced observers, the percentage of correct answers for identifying the color attribute responsible for a color difference was only 72.4%, the random probability being 33.3%. There were no significant differences between the results found by men and women. The worst distinguished attribute was Chroma, that is, the least frequent confusion was between Hue and Value or vice versa. Value differences were more easily detected for achromatic than for chromatic pairs, both for experienced and inexperienced observers. With respect to the size of the color differences, we observed that large hue differences were more easily identifiable than smaller ones, and a constant Hue was more identifiable when the entire color difference was small. © 2000 John Wiley & Sons, Inc. Col Res Appl, 25, 356–367, 2000     

Hue uniformity and the CIELAB space and color difference formula

The hue uniformity of the CIELAB system is investigated using a hue circle of Munsell colors at value 6 and chroma 14 and experimentally determined hue coefficient data. CIELAB hue differences for equal Munsell hue increments are found to vary up to nearly a factor 4, and hue coefficients differ from the experimentally determined ones by up to 40% at certain wavelengths. Dominant wavelengths assigned by the CIELAB system to individual Munsell hues are found to vary up to 35 nm from those of the Munsell Renotations. Four other color space systems are compared with widely differing but comparable results. The CIE 2° color-matching functions are adapted to result in a set of opponent-color functions accurately representing the Munsell Hue and Chroma data. A call is made for the experimental determination of the “standard hue observer” as a step toward an improved color space/color-difference formula. © 1998 John Wiley & Sons, Inc. Col Res Appl, 23, 314–322, 1998     

酵母菌和果胶酶对干红葡萄酒发酵浸提的影响

采用CIELAB法研究蛇龙珠干红葡萄酒酿造过程中颜色的变化规律,探讨不同酵母和果胶酶对原料葡萄色素的浸提作用及引起颜色变化的影响情况。结果表明,蛇龙珠干红葡萄酒酿造过程中,红色色调值在发酵前期迅速上升,颜色在第3天最深;后期逐渐下降;黄色色调值逐渐上升;果胶酶对颜色的影响略高于酵母;Zymaflore F15酵母促进果香的生成;而Actiflore F33酵母转化乙醇能力较高;Lafase HE果胶酶对单宁、色素的浸提更加有利;而Optizyme果胶酶有利于酒液的澄清;Zymaflore F15酵母与Lafase HE果胶酶组合,更适于酿造更显果香、圆润、平衡和醇厚的蛇龙珠干红葡萄酒。     

A colorimetric study of oenin copigmented by procyanidins

A colorimetric method was used to analyse the influence of procyanidin structure on colour changes of malvidin 3‐O‐glucoside (oenin) solution resulting from copigmentation. The study was performed in hydroalcoholic citrate/phosphate buffer solution (120 g L^?1) at pH 3.6 and ionic strength 0.2 mol L^?1. Chromatic L*, a* and b* coordinates (CIELAB, D65/10° illuminant/observer condition) obtained from spectral curves recorded between 360 and 830 nm allowed the calculation of lightness L*, chroma C* and hue angle h_ab. In general, addition of copigment induced colour enhancement (loss of lightness and increased chroma). The prevailing parameters affecting colour changes were lightness and chroma for monomers and lightness and hue for procyanidins B5 and B8 (C4–C6 dimers). A small blueing effect was observed only for catechin monomer‐copigmented solutions. For procyanidin copigments, as the structural complexity of the copigment increased, the hue angle moved to yellower values. The ester gallate of dimer B2 produced the strongest modification of colour attributes of oenin solution. Copyright © 2006 Society of Chemical Industry     

CIE 1976(L*a*b*)色空间方法测定葡萄酒颜色的研究

首次建立了葡萄酒颜色的数字化测量方法。用CIE1976(L*a*b*)色空间方法,实现了葡萄酒颜色的数字化测量。对测定条件、主要成分的干扰和稀释的影响,对标准照明体和观察者条件进行了验证。检出限分别是L*0.034,a*0.0344,b*0.0448,C*0.0418,h*0.2238。克服了人工观察和描述语言颜色方法的缺点,实现了葡萄酒颜色的数字化测量、颜色的传递、再现和溯源,快速、精确的实现了葡萄酒颜色的客观测量。     

Study of natural teeth color according to toothguide 3d master through cluster analysis

How natural teeth color are grouped with Toothguide 3D Master according to color coordinates, L*, C*, and h* is reported. Tooth color was measured through the Easyshade Compact (Vita‐Zahnfabrik) spectrophotometer using a sample of 1361 subjects aged between 16 and 89 years. The color of the middle third of the maxillary central incisor was registered according to the Toothguide 3D Master nomenclature and the coordinates L*, C*, and h*. Cluster analysis and the SPAD 5.5 statistical package were applied for data processing. Of the 1361 participants, only 545 (40%) had a match among the 26 physical shade tabs of the Toothguide 3D Master. Statistical analysis revealed the existence of four cluster groups: Cluster 1 comprised shade tabs 1M1–2L1.5–2M1; cluster 2 comprised 1M2–2L2.5–2M2–2M3–2R2.5–3M2–3L2.5; cluster 3 comprised 2R1.5–3L1.5–3M1–3R1.5–4L1.5–4M1; and cluster 4 comprised 3M3–3R2.5–4M2–4L2.5–4R1.5–4R2.5–4M3–5M1–5M2–5M3. Statistically significant differences (P < 0.0.1) were also found, both in the color dimension, and among the four cluster groups revealed. Taking into account the limitations of this study, the natural teeth color can be grouped into four clusters by following coordinates L*, C*, and h,* resulting from the compact spectrophotometer Vita Easyshade. Natural teeth color are not distributed homogeneously with Toothguide 3D Master according to color coordinates. © 2014 Wiley Periodicals, Inc. Col Res Appl, 41, 101–107, 2016