scholarly journals Color Appearance Shifts Depending on Surface Roughness, Illuminants, and Physical Colors

Author(s):  
Youngjoo Chae

Abstract Texture is an important synesthetic design element used in textile products. The three-dimensional surface of texture changes the amount and angle of reflected light causing a color appearance change from its original color. In this work, for a wide range of colors, it was quantitatively analyzed how the color appearances change depending on different textures and illumination, such as CIE standard illuminants A, F11, F2, and D65. It was found that strong-textured fabrics (with a surface roughness Ra of 0.46 mm) had larger hue appearance changes and consequent overall color appearance changes from their true colors due to illuminants than non-textured papers (with a surface roughness Ra of 0.03 mm). Between two types of fabrics with different textures of 0.25 and 0.46 mm, however, there was no significant difference in the magnitude of color appearance changes, indicating that the difference in surface roughness greater than 0.43 mm can produce significant differences in color appearance changes induced by illumination. It was also found that the magnitude and direction of color appearance changes under different CIE illuminants differed significantly according to the physical chroma and hue of the surface.

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1550
Author(s):  
Soo-Yeon Yoo ◽  
Seong-Kyun Kim ◽  
Seong-Joo Heo ◽  
Jai-Young Koak ◽  
Joung-Gyu Kim

Previous studies on accuracy of three-dimensional (3D) printed model focused on full arch measurements at few points. The aim of this study was to examine the dimensional accuracy of 3D-printed models which were teeth-prepped for three-unit fixed prostheses, especially at margin and proximal contact areas. The prepped dental model was scanned with a desktop scanner. Using this reference file, test models were fabricated by digital light processing (DLP), Multi-Jet printing (MJP), and stereo-lithography apparatus (SLA) techniques. We calculated the accuracy (trueness and precision) of 3D-printed models on 3D planes, and deviations of each measured points at buccolingual and mesiodistal planes. We also analyzed the surface roughness of resin printed models. For overall 3D analysis, MJP showed significantly higher accuracy (trueness) than DLP and SLA techniques; however, there was not any statistically significant difference on precision. For deviations on margins of molar tooth and distance to proximal contact, MJP showed significantly accurate results; however, for a premolar tooth, there was no significant difference between the groups. 3D color maps of printed models showed contraction buccolingually, and surface roughness of the models fabricated by MJP technique was observed as the lowest. The accuracy of the 3D-printed resin models by DLP, MJP, and SLA techniques showed a clinically acceptable range to use as a working model for manufacturing dental prostheses


2010 ◽  
Vol 150-151 ◽  
pp. 1063-1067
Author(s):  
Fei Fei Zhu ◽  
Zhi Li Zhong ◽  
Zong Fu Guo

The three composite boards which were made of continuous basalt fiber (CBF) and polypropylene fiber (PP) in different fiber ratios were researched on this paper. The manufacturing forming process included blending, carding, web formation, laminating and compression molding orderly. The tension and bending properties were investigated experimentally, and then dual variance analysis was used to show the significant difference of the mechanical property in the transverse and longitudinal orientation as well the appreciable impact of different fiber ratios to the mechanical property. The results show that the difference of the tension and blending strength in the same direction, among composite boards in different fiber proportions, is about 1~10Mpa; the difference in the same fiber proportion, between transverse and longitudinal, vary within a wide range from 10Mpa to 30Mpa. The results of variance analysis have also proved the conclusion, the difference between transverse and longitudinal is more significant than the difference among different fiber proportions. In the similar study, the significance hadn’t been seen sufficiently, so this paper provides reference to the actual application of the composite board.


Author(s):  
A H A Baazil ◽  
J G G Dobbe ◽  
E van Spronsen ◽  
F A Ebbens ◽  
F G Dikkers ◽  
...  

Abstract Objective This study aimed to compare the necessary scutum defect for transmeatal visualisation of middle-ear landmarks between an endoscopic and microscopic approach. Method Human cadaveric heads were used. In group 1, middle-ear landmarks were visualised by endoscope (group 1 endoscopic approach) and subsequently by microscope (group 1 microscopic approach following endoscopy). In group 2, landmarks were visualised solely microscopically (group 2 microscopic approach). The amount of resected bone was evaluated via computed tomography scans. Results In the group 1 endoscopic approach, a median of 6.84 mm3 bone was resected. No statistically significant difference (Mann–Whitney U test, p = 0.163, U = 49.000) was found between the group 1 microscopic approach following endoscopy (median 17.84 mm3) and the group 2 microscopic approach (median 20.08 mm3), so these were combined. The difference between the group 1 endoscopic approach and the group 1 microscopic approach following endoscopy plus group 2 microscopic approach (median 18.16 mm3) was statistically significant (Mann–Whitney U test, p < 0.001, U = 18.000). Conclusion This study showed that endoscopic transmeatal visualisation of middle-ear landmarks preserves more of the bony scutum than a microscopic transmeatal approach.


2020 ◽  
Vol 32 (7) ◽  
pp. 741-752
Author(s):  
Yongqiang Wang ◽  
Changhui Feng ◽  
Ruoyu Fei ◽  
Yu Luo

To study the ageing characteristics of epoxy resin composite insulation in dry-type transformers in high-temperature environments, glass fibre-reinforced epoxy resin samples were placed in a hot air ageing environment at 130°C for testing. Dielectric properties, partial discharge (PD), microscopic morphology, three-dimensional morphology and Fourier transform infrared spectroscopy of aged samples were periodically tested. The results show that during the ageing process, the change in the surface morphology of the sample leads to an overall upward trend in surface roughness, and the older the sample, the faster the surface roughness increases; changes in the surface morphology and three-dimensional morphology of the material constitute the basis for judging the condition of the insulating surface and the state of ageing development. Microcracks are the direct cause of debonding of glass fibres and epoxy matrix. Degradation of the sample during the ageing process generates many free radicals, which enhances the polarisation ability of the sample and increases both the dielectric constant and the dielectric loss factor. The real part of the complex dielectric constant is more sensitive to the ageing response of the sample. The older the sample, the greater the effect on the results of the dielectric spectrum test. Since the aged sample generates more hot electrons during the PD process and makes it easier to inject electrons into the material, the PD of the sample is rendered more intense by thermal ageing. There is a significant difference between the degradation mechanism of the thermal ageing and PD. The samples subjected to PD after thermal ageing produce new groups, and the degradation of the samples is more severe than that caused by thermal ageing, or PD, alone.


2016 ◽  
Vol 40 (2) ◽  
pp. 201-205 ◽  
Author(s):  
C. J. Daly ◽  
J. M. Bulloch ◽  
M. Ma ◽  
D. Aidulis

Sophisticated three-dimensional animation and video compositing software enables the creation of complex multimedia instructional movies. However, if the design of such presentations does not take account of cognitive load and multimedia theories, then their effectiveness as learning aids will be compromised. We investigated the use of animated images versus still images by creating two versions of a 4-min multimedia presentation on vascular neuroeffector transmission. One version comprised narration and animations, whereas the other animation comprised narration and still images. Fifty-four undergraduate students from level 3 pharmacology and physiology undergraduate degrees participated. Half of the students watched the full animation, and the other half watched the stills only. Students watched the presentation once and then answered a short essay question. Answers were coded and marked blind. The “animation” group scored 3.7 (SE: 0.4; out of 11), whereas the “stills” group scored 3.2 (SE: 0.5). The difference was not statistically significant. Further analysis of bonus marks, awarded for appropriate terminology use, detected a significant difference in one class (pharmacology) who scored 0.6 (SE: 0.2) versus 0.1 (SE: 0.1) for the animation versus stills group, respectively ( P = 0.04). However, when combined with the physiology group, the significance disappeared. Feedback from students was extremely positive and identified four main themes of interest. In conclusion, while increasing student satisfaction, we do not find strong evidence in favor of animated images over still images in this particular format. We also discuss the study design and offer suggestions for further investigations of this type.


2017 ◽  
Vol 30 (4) ◽  
pp. 439-444 ◽  
Author(s):  
Ester Del Duca ◽  
Francesca Farnetani ◽  
Nathalie De Carvalho ◽  
Ugo Bottoni ◽  
Giovanni Pellacani ◽  
...  

Psoriasis is a chronic inflammatory skin disease affecting 2%–3% of the population. The wide range of drugs currently available for its treatment could be associated, in the long term, with organ toxicity and adverse events, thus, clinical monitoring throughout treatment is required. This investigator-initiated trial (IIT) evaluated the efficacy and the safety of a vitamin B12-containing ointment in comparison with glycerol-petrolatum-based emollient cream used twice a day to treat mild-to-moderate plaque psoriasis for a period over 12 weeks followed by a wash-out observation period of 4 weeks. This study was conducted as a randomized, controlled, single-blind, intra-patient left- to right-side trial comparing the efficacy and safety of vitamin B12-containing ointment (M-treatment) with a glycerol-petrolatum-based emollient cream (C-treatment). The Psoriasis Area Severity Index (PASI) was determined at baseline (T0), at time points T2 (14 days), T4 (4 weeks), T8 (8 weeks), T12 (12 weeks) and 4 weeks after the end of the wash-out period (F1). In total, 24 patients with plaque psoriasis were randomized to receive left- or right-side treatment with B12 ointment. From time point T2 to time point F1, there was a statistically significant difference in PASI reduction between M-treatment side and C-treatment side. At time point T 12, the difference between the mean reductions from baseline PASI scores by 5.92 ± 2.49 (87, 6%) in the M-treatment side versus 1.08 ± 1.02 (23, 1%) C-treatment side was statistically highly significant ( PWex < 0.001). On the contemporary panorama in the treatment of psoriasis, we conclude that vitamin B12 ointment will represent a new concrete therapy option and should be considered in the update of therapeutic algorithm for the treatment of psoriasis


2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Sandeep Kuriakose ◽  
Paolo Parenti ◽  
Salvatore Cataldo ◽  
Massimiliano Annoni

Additive manufacturing (AM) of metal offers matchless design sovereignty to manufacture metallic microcomponents from a wide range of materials. Green-state micromilling is a promising method that can be integrated into the AM of metallic feedstock microcomponents in typical extrusion-based AM methods for compensating the inability to generate microfeatures. The integration enables the manufacturing of complex geometries, the generation of good surface quality, and can provide exceptional flexibility to new product shapes. This work is a micromachinability study of AISI316 L feedstock components produced by extrusion-based AM where the effects of workpiece temperature and the typical micromilling parameters such as cutting speed, feed per tooth, axial depth of cut, and air supply are studied. Edge integrity and surface roughness of the machined slots, as well as cutting forces, are analyzed using three-dimensional microscopy and piezoelectric force sensor, respectively. Green-state micromilling results were satisfying with good produced quality. The micromilling of heated workpieces (45 °C), with external air supply for debris removal, showed the best surface quality with surface roughness values that reached around Sa = 1.5 μm, much smaller than the average metal particles size. Minimum tendency to borders breakage was showed but in some cases microcutting was responsible of the generation of surface defects imputable to lack of adhesion of deposited layers. Despite this fact, the integrability of micromilling into extrusion-based AM cycles of metallic feedstock is confirmed.


2021 ◽  
Vol 80 (1) ◽  
pp. 287-295
Author(s):  
Vinicius Zanetti ◽  
Marcelo Saldanha Aoki ◽  
Paul Bradley ◽  
Christopher Carling ◽  
Thomas Kisil Marino ◽  
...  

Abstract This study examined changes in match running performance (MRP) in Under-14 soccer players (13.5 ± 0.7 yrs) during a congested match schedule (CMS) (4 matches played within a 5-day period). It also examined the difference in salivary testosterone (sT) concentration, somatic maturation, jumping tests, and Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IR1) between the players selected to play (SLG; group who participated in all matches) and players non-selected to play (NSG). A significant difference was observed for the frequency of decelerations (DEC) across matches (match 4 vs. matches 1, 2 and 3; p = 0.05; partial ƞ2 = 0.20). No difference between matches was observed for total running distance (TRD), high-speed running distance (HSRD), and frequency of accelerations (ACC) (p > 0.05). A wide range for within-player coefficient of variation (CV) values was observed for all MRP variables (range: 10.5 = TRD to 30.6 = HSRD). No difference between SLG and NSG for any of the assessed variables was observed (p > 0.05). The findings suggest that DEC was the most pertinent variable for monitoring changes in MRP during the CMS. In addition, at an elite youth soccer level, the biological maturity and fitness might not influence selection to play.


2013 ◽  
Vol 11 (2) ◽  
pp. 43-47
Author(s):  
RIANI DWI HASTUTI ◽  
DIDING PRASETYO ◽  
SRI HARTATI HADINOTO

Hastuti RD, Prasetyo D, Hadinoto SH. 2013. The difference of caffeic acid phenethyl ester level in ethanol extract propolis and water extract propolis. Biofarmasi 11: 43-47. Propolis is a natural product derived from plant resin collected by honeybeen and its composition has wide range of biological activity. CAPE is the ester of caffeic acid, a derivative of phenolic acid, a flavonoid-like compound, one of the major components of propolis. CAPE is reported can protect nephrotoxicity due to cisplatin induction, inhibiting the growth of various types of abnormal cells, having an anti-inflammation activity, antioxidant activity, cyclooxygenase activity, vasodilatation activity in rat aorta, potential inhibitor of nitric oxidant, inhibitor oxidative process, and effectively suppress the growth of cataract in rat. Propolis can not be used as raw material, and it must be purified by extraction with solvent. Different solvents may extract different compounds, influencing its activity. The purpose of this research was to determine the difference levels of CAPE in ethanol extract propolis and water extract propolis. This research was a pure experimental research using the post-test only design. The sample of this research was raw propolis taken from bees farming in Gejen RT. 03 RW. 02, Kerjo, Karanganyar. Sampling was performed by a purposive sampling. Sample was extracted with a maserasion method with the solvents of ethanol and water. In each extract propolis was made five samples. The determination of the level of CAPE on propolis was performed by using UV-Vis spectrophotometry with Prussian Blue method. The data of the level of CAPE was analyzed by the statistical test of independent t-test. The results showed that the average of CAPE level in ethanol extract propolis was 12.268±0.658 μg/mL and the average of CAPE level in water extract propolis was 5.564±0.332 μg/mL, with p=0.125 (p>0.05). There was no significant difference between extract ethanol propolis and water extract propolis.


2021 ◽  
Vol 50 (10) ◽  
pp. 3059-3065
Author(s):  
Aini Hayati Abdul Rahim ◽  
Zubaidah Zanul Abidin ◽  
Norsiah Yunus

Selective laser melting (SLM) is a new technique in fabricating cobalt-chromium denture framework. However, the surface properties of cobalt-chromium denture framework fabricated using the aforementioned technique have not been widely investigated. The aim of this paper was to investigate the surface roughness of cobalt-chromium alloy in removable partial denture fabricated with SLM technique. Cobalt-chromium denture frameworks were fabricated with two techniques (n = 10); the conventional lost-wax casting (conventional group) and SLM techniques (SLM group). Specimens from the conventional group were subjected to the standard cobalt-chromium denture polishing protocols. No treatment was employed for specimens from the SLM group. All specimens were subjected to surface roughness measurement on polished and fitting surfaces using non-contact optical three-dimensional metrology and surface roughness analysis machine (Infinite Focus Real 3D Alicona). Statistical analysis showed no significant difference in surface roughness between the specimens from conventional and SLM groups (p > 0.05). There was no statistically significant difference in surface roughness between the polished and fitting surfaces of SLM specimens (p > 0.05). Surface roughness quality of the cobalt-chromium denture framework fabricated with the SLM technique is comparable to that fabricated with the conventional lost-wax casting technique. The surface roughness of SLM fabricated cobalt-chromium denture frameworks carries the same surface roughness quality between the polished and fitting surfaces.


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