Search

In view of the problems of few data, complex influencing factors and low prediction accuracy of fashion color, a discrete GM(1,1)model is proposed to predict fashion color. The study takes the final fashion color case published by China Textile Information Center in spring and summer of 2013—2019 as the research object, and HSV color system as the basis of color quantification, on which a prediction model of fashion color is established. To verify the effect of the model, GM(1,1)model is compared. The results show that the DGM(1,1)model improves the prediction performance with an average relative error of 4.493%, the residual value tends to be stable and the accuracy level is excellent, which is significantly better than 9.622% of EGM(1,1), 4.497% of ODGM(1,1)and 4.495% of EDGM(1,1). The process is simple and the prediction is accurate, which provides a reference basis and practical guidance for fashion color prediction with large fluctuation of data series. [ABSTRACT FROM AUTHOR]

This study discusses a mechanism of inkjet printing and investigates the effect of ink contrast on the color phase of the printed object. Inkjet printing is a popular printing method for home use, but its color repeatability is occasionally broken. To verify this problem, we calculated the radiative transfer equation on the surface of an object printed by an inkjet printer, and the color was quantitatively estimated. The ink dot area and spectral reflectance of the printed samples were measured. Furthermore, the spectral reflectance of the objects printed with different dot areas were theoretically calculated. By comparing the measured and calculated reflectance, we estimated the scattering coefficient of the paper and absorption coefficient of the ink. We quantitatively calculated the color with the HSV color system. The hue changed with dot area rate. It is considered that this is caused by the broad range of the spectral absorption coefficients of inks. We believe that this study will aid the development of ink without color change and improve the color repeatability of inkjet printers. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new method based on digital image analysis was applied to determine urea in UHT milk. • The digital image acquisition apparatus was built with PVC tubes and other low-cost materials. • The method presents itself as an efficient alternative to the FT-IR technique to determine urea. • Digital image analysis proved to be a promising technique to assess adulteration and milk quality. This research demonstrates the development, optimization and application of a new low-cost detection system, based on digital image analysis, for the detection of urea in ultra-high-temperature (UHT) milk samples. The apparatus built in the laboratory, allows the capture of images through a simple system built by polyvinyl chloride (PVC) tubes, a digital microscope and a peristaltic mini-pump, after the colorimetric reaction between urea and diacetylmonoxime (butane-2,3-dionammonoxime). The red, green and blue (RGB) and hue, saturation and value (HSV) color systems were studied, with the saturation channel of the HSV color system selected as the analytical signal. Subsequently, the experimental chemical conditions were evaluated through multivariate experimental designs and the optimal conditions were defined. The proposed method was validated, and the detection and quantification limits presented by the method were 0.35 mg L−1 and 0.52 mg L−1, respectively; precision, ranged between 1.6 and 2.8 %. The results were compared with those obtained using the mid-infrared technique and no statistically significant differences were observed at a 95 % confidence level. The proposed method was applied to eight UHT milk samples that presented urea content ranging from 187 to 386 mg L−1. The mean values obtained are in agreement with values presented in other studies for the determination of urea in milk. The results indicated that the system described and validated here is promising and can be applied to assess the authenticity and quality of milk. [ABSTRACT FROM AUTHOR]