Purpose
The purpose of this paper is provide a broad view for the standardization efforts of color quality evaluation of color 3D printing techniques. Further, this review paper demonstrates the ...processes and color properties of most color 3D printing techniques with specific devices and applications to extend the range of possible memberships of standardization group.
Design/methodology/approach
Six color 3D printing techniques including plastic-based, paper-based, powder-based, organism-based, food-based and metal-based color 3D printing have been introduced and illustrated with colorization principles and forming features in detail. Moreover, for printed 3D color objects, literature about color measurement, color specification and color reproduction are described and analyzed, respectively.
Findings
Four color 3D printing techniques including plastic-based, paper-based, powder-based and food-based color 3D printing show great affinity toward standardization of color quality evaluation, while their colorization principles indicate that it is difficult with a single standard frame. It is possible to develop a completed color quality evaluation standard for color 3D printing based on approaches in color 2D printing when color measurement method and devices are standardized together.
Originality/value
The paper provides an important guide focusing on the efforts to standardize the colorization processes and color quality evaluation of the color 3D printing techniques.
Old textiles represent important samples of the mobile cultural heritage, having implications on the social and spirituallife of each population. In order to keep them in the best condition, it is ...necessary to implement methods to preventdamages, but also to rehabilitate and clean the already affected fabrics. In the case of textiles that need to be treated,a fundamental thing is the unaltered preservation of the initial characteristics of the materials, even after theinterventions. The aim of our study is to test the feasibility of a non-invasive alternative to usual chemicals for cleaningtextiles; Chitosan’s antimicrobial and cleaning effects on a pair of Romanian traditional cotton trousers, from Maramuresarea was analyzed. A few images were taken from SEM of untreated and treated fabric with Chitosan solution usingdifferent magnifications, in order to check the changes on the fabric surface. The purpose was to observe if there aresome color changes after Chitosan treatment, so the CIELAB color values (L, a, b) of untreated and treated sampleswere analyzed. The analysis of the treated samples revealed strong antimicrobial effects of Chitosan
The advancement of digital printing technologies facilitates alternative production methods to print certified reflective foils used to produce the faces of retroreflective traffic signs. Such ...products are approved and tested for certification in accordance with standards such as SR EN 12899-1:2007, regardless of production methods while the chromaticity and luminance factors are normative to qualify the product. This paper presents a method for process control and quality assurance using measurement devices and tools employed specifically by graphic technology. The core element is the correlation of the reference colour space (CIELAB, D50) with the standard reference from SR EN 12899-1:2007 (CIExyY, D65), also considering the conceptual difference from circular/elliptical tolerances typically used in printing processes and the colour box coordinates defined by the standard.
The relationship between instrumental colorimetric values (L*, a*, b*, the ratio of reflectance at 630nm and 580nm) and consumer perception of acceptable beef colour was evaluated using a web-based ...survey and standardised photographs of beef m. longissimus lumborum with known colorimetrics. Only L* and b* were found to relate to average consumer opinions of beef colour acceptability. Respondent nationality was also identified as a source of variation in beef colour acceptability score. Although this is a preliminary study with the findings necessitating additional investigation, these results suggest L* and b* as candidates for developing instrumental thresholds for consumer beef colour expectations.
The use of agricultural waste is becoming more common with the spread of awareness of sustainable life. In the present study, different concentrations (10 gr/L, 15 gr/L, 20 gr/L) of aqueous extracts ...were obtained from tomato (Solanum lycopersicum) leaves as agricultural waste and fabrics containing 100% wool were coloured with these extracts by using infra-red dyeing machine. Aluminium, iron and copper based mordants, which are frequently used in natural dyeing, were added to the extracts. After dyeing process, colours in alluring brown, green and yellow tones were obtained in the fabrics. According to the spectrophotometer measurements, colour yield (K/S) of the samples increased proportionally with increasing concentrations. Washing and rubbing fastness of the dyed wool samples were good, except for the samples dyed with iron-based mordant added extract.
Summary
Beetroot is a vegetable rich in betalains, which contains colouring and functional properties that can be beneficial in processing dairy products. In order to combine the benefits of yogurt ...and beetroot, the objective was to elaborate whole yogurts added with beetroot syrup in the following concentrations: 0% (T1), 13% (T2), 17% (T3) and 20% (T4), and to determine its physicochemical characteristics, biological activities and sensory attributes by the Check‐All‐That‐Apply (CATA) method and acceptance by hedonic scale, compared to the control yogurt with the addition of 5% w/w sucrose (T1). The beet syrup had a high content of betacyanins and betaxanthins (491.01 ± 1.67 mg.L−1 and 226.15 ± 0.26 mg. L−1 respectively). There was a progressive increase in the inhibition of ACE, α‐glucosidase and α‐amylase and antioxidant activity as the syrup content increased in the formulations (P < 0.05). The sensory attributes ‘acid aroma’, ‘earthy flavour’, ‘bitter taste’ and ‘fluid texture’ were considered negative preference drivers for T2 and T4, while T3 yogurt was the most appreciated by consumers. Despite showing colour changes during storage, adding beet syrup promoted a naturally attractive colour to the yogurts. The results suggest that the addition of beetroot syrup in yogurts, in addition to being an alternative to using artificial colouring in the industry, can provide health benefits to consumers by forming bioactive compounds.
The study was carried out based on three treatments of yogurt with different concentrations of beet syrup and the conventional sample to analyse physical–chemical aspects, biological activity and sensory acceptance. The pH and moisture of the samples were not affected by the different concentrations of beet syrup (P < 0.05), while the colour showed changes throughout the storage period. The biological activity of samples with beet syrup showed higher means of a‐amylase and a‐glucosidase inhibition and greater antioxidant and antihypertensive action (P < 0.05). Sample T3, among the samples with beet syrup, had the best sensory acceptance.
An Ishihara-style test of animal colour vision Cheney, Karen L; Green, Naomi F; Vibert, Alexander P ...
Journal of experimental biology,
01/2019, Letnik:
222, Številka:
Pt 1
Journal Article
Recenzirano
Odprti dostop
Colour vision mediates ecologically relevant tasks for many animals, such as mate choice, foraging and predator avoidance. However, our understanding of animal colour perception is largely derived ...from human psychophysics, and behavioural tests of non-human animals are required to understand how colour signals are perceived. Here, we introduce a novel test of colour vision in animals inspired by the Ishihara colour charts, which are widely used to identify human colour deficiencies. In our method, distractor dots have a fixed chromaticity (hue and saturation) but vary in luminance. Animals can be trained to find single target dots that differ from distractor dots in chromaticity. We provide MATLAB code for creating these stimuli, which can be modified for use with different animals. We demonstrate the success of this method with triggerfish,
, which quickly learnt to select target dots that differed from distractor dots, and highlight behavioural parameters that can be measured, including success of finding the target dot, time to detection and error rate. We calculated discrimination thresholds by testing whether target colours that were of increasing colour distances (Δ
) from distractor dots could be detected, and calculated discrimination thresholds in different directions of colour space. At least for some colours, thresholds indicated better discrimination than expected from the receptor noise limited (RNL) model assuming 5% Weber fraction for the long-wavelength cone. This methodology could be used with other animals to address questions such as luminance thresholds, sensory bias, effects of sensory noise, colour categorization and saliency.
In this paper, I present arguments and suggestions for the improvement of the scientific study of synaesthesia, and particularly grapheme-colour synaesthesia in relation to psycholinguistic research, ...although the principles I advocate can be easily adapted to any subfield of synaesthesia study. I postulate that the current state of research on synaesthesia in general, and on grapheme-colour synaesthesia in particular, suffers from a lack of exploratory evidence and essential groundwork upon which to build hypothesis-testing studies. In particular, I argue that synaesthesia research has been artificially bounded by assumptions about the nature of synaesthetic experiences, which constrain both the questions that researchers ask and the way in which they go about answering those questions. As a specific example, I detail how much of the current research on grapheme-colour synaesthesia is built to accommodate two major assumptions about the nature of colours for letters and for words-assumptions which I will contend are not universally true, and the exceptions to which point to a much richer and heterogeneous understanding of synaesthetic experience than current research practices capture. The top-down predetermination of what is important or meaningful to measure, and what is not, has subsequently impeded a full understanding of what synaesthesia is and how it works. I argue that these assumptions must be carefully addressed and evaluated, both for the particular case of grapheme-colour synaesthesia and for the field as a whole, to move towards a holistic and fruitful understanding of synaesthesia as a phenomenon and as a tool to study language, thought and perception. To that end, I propose specific recommendations for synaesthesia researchers to solidify and expand their understanding and to capture the actual experience of synaesthetes. This article is part of a discussion meeting issue 'Bridging senses: novel insights from synaesthesia'.
The use of traditional biocides to halt or reduce biodeterioration is increasingly deterred, due to risks for human health and the environment, as well as for potential interference with stone ...materials. Alternative and eco-friendly substances are needed to limit these issues. Here we aim to evaluate the devitalization of lichens by a new bio-based product: wood distillate (also known as pyroligneous acid), a by-product of the use of plant biomass to produce bioenergy by pyrolysis without the addition of synthetic chemicals. We compared cellulose poultice applications of wood distillate at a concentration of 10% and two common chemical biocides against four epilithic lichen species on Pietra Serena, a sandstone widely used in Europe. The efficiency of devitalization was measured in terms of lichen vitality expressed by chlorophyll a fluorescence emission FV/FM and F0. Furthermore, we evaluated the effects of wood distillate on physical properties of the stone material of relevance for its conservation, including colour, resistance to dissolution, and surface hardness. Wood distillate was as effective as chemical biocides in devitalizing the thalli and did not cause any relevant interference with the assayed sandstone, although a limited dissolution of its calcite cement was detected.
Display omitted
•10% wood distillate devitalizes lichens as effectively as traditional biocides•The effect is verified on 4 species commonly growing on Pietra Serena sandstone•The application negligibly interferes with the sandstone colour and hardness•Wood distillate may be an alternative to control biodeterioration on sandstone•Some dissolution of calcite excludes the application on delicate heritage surfaces
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