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Fast full-color pathological imaging using Fourier ptychographic microscopy via closed-form model-based colorization 被引量:2
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作者 Yanqi Chen Jiurun Chen +4 位作者 Zhiping Wang Yuting Gao Yonghong He Yishi Shi An Pan 《Advanced Photonics Nexus》 2025年第2期7-16,共10页
Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution fo... Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution for high-throughput digital pathology,combining high resolution,large field of view,and extended depth of field(DOF).However,the full-color capabilities of FPM are hindered by coherent color artifacts and reduced computational efficiency,which significantly limits its practical applications.Color-transferbased FPM(CFPM)has emerged as a potential solution,theoretically reducing both acquisition and reconstruction threefold time.Yet,existing methods fall short of achieving the desired reconstruction speed and colorization quality.In this study,we report a generalized dual-color-space constrained model for FPM colorization.This model provides a mathematical framework for model-based FPM colorization,enabling a closed-form solution without the need for redundant iterative calculations.Our approach,termed generalized CFPM(gCFPM),achieves colorization within seconds for megapixel-scale images,delivering superior colorization quality in terms of both colorfulness and sharpness,along with an extended DOF.Both simulations and experiments demonstrate that gCFPM surpasses state-of-the-art methods across all evaluated criteria.Our work offers a robust and comprehensive workflow for high-throughput full-color pathological imaging using FPM platforms,laying a solid foundation for future advancements in methodology and engineering. 展开更多
关键词 Fourier ptychographic microscopy color transfer dual-color-space constrained model
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基于CNCSCOLOR的色相-色调感性模型构建
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作者 薛媛 白圆圆 姜茸凡 《丝绸》 CAS 北大核心 2025年第1期1-10,共10页
中国应用色彩体系(CNCSCOLOR)基于中国人眼视觉实验所开发,但在国外色彩体系的早期市场占有下没有得到广泛应用。本研究尝试开发一套易于学习推广的模型,以促进其普及和应用。首先通过对三维色彩体系的研究分析,借鉴日本PCCS色彩体系,... 中国应用色彩体系(CNCSCOLOR)基于中国人眼视觉实验所开发,但在国外色彩体系的早期市场占有下没有得到广泛应用。本研究尝试开发一套易于学习推广的模型,以促进其普及和应用。首先通过对三维色彩体系的研究分析,借鉴日本PCCS色彩体系,构建了简化的二维色相-色调基本模型,其中色调融合了色彩属性明度和彩度。模型用直角坐标定位,水平轴为彩度,垂直轴为明度,5种无彩色将明度轴分为四段,12个20色色相环即12种有彩色色调,按照明度与彩度的大小有序分布于平面内。确定构成基本模型的240种有彩色和5种无彩色的选色规则,选出色彩,组合完善基本模型。其次,研究确定12种有彩色色调的感性,得到色相-色调感性模型。通过主观调查初步分析得到有彩色色调的感性,再实施客观眼动实验进一步验证调查结果,最终确定12个有彩色色调的感性分别是鲜明的、明快的、强烈的、浑厚的、清新的、淡雅的、浑浊的、厚重的、浅淡的、暗淡的、灰暗的、黑暗的。研究得到的色相-色调模型包含的色彩数量少,采用二维的平面布局,使初学者易懂易记,便于普及应用;且色调命名符合中国人的情感特征,将用于后续的感性配色模型构建,便于设计师和消费者快速进行精准的产品色彩搭配,对中国本土色彩体系的发展和色彩设计水平的提升具有实际的应用价值。 展开更多
关键词 CNCScolor PCCS色彩体系 色相-色调基本模型 色相-色调感性模型 主观调查 眼动实验
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The Impact of Photo Editing on Dermatological Perceptions in Skin of Color
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作者 Radhika Misra Alejandra Sataray-Rodriguez +7 位作者 Bret-Ashleigh Coleman Chinecherem Chime-Eze Christina Tolete Barda Haghighat John Monroe Guang Orestes Christina Randolph Kelly Frasier 《Journal of Biosciences and Medicines》 2025年第2期435-449,共15页
The pervasive use of photo editing applications such as Photoshop and FaceTune has significantly altered societal beauty standards, particularly for individuals with skin of color, often leading to unrealistic expecta... The pervasive use of photo editing applications such as Photoshop and FaceTune has significantly altered societal beauty standards, particularly for individuals with skin of color, often leading to unrealistic expectations regarding skin appearance and health. These tools allow users to smooth skin textures, lighten skin tones, and erase imperfections, perpetuating Eurocentric beauty ideals that frequently marginalize the natural diversity of skin tones and textures. Consequently, individuals with skin of color may seek dermatological interventions—such as skin lightening treatments, aggressive acne scar revisions, and other cosmetic procedures—aimed at achieving appearances that align more closely with digitally manipulated images. This pursuit of an unattainable aesthetic can result in increased dissatisfaction with common skin conditions like hyperpigmentation and keloids, which are often misrepresented in edited photos. Additionally, the psychological impact of these alterations can exacerbate feelings of inadequacy, contributing to conditions such as anxiety and body dysmorphic disorder. Dermatologists face the dual challenge of addressing patients’ clinical needs while also managing their expectations shaped by digital enhancements. To combat this, it is essential for dermatologists to integrate patient education that emphasizes the beauty of diverse skin tones and the discrepancies between digital images and authentic skin health. By fostering an understanding of realistic outcomes and promoting the acceptance of natural skin characteristics, dermatologists can empower individuals with skin of color to prioritize authentic skin health over digitally influenced ideals, ultimately leading to more satisfying dermatological care and improved self-image. 展开更多
关键词 Skin of color colorISM Photo Editing Applications Eurocentric Beauty Standards HYPERPIGMENTATION KELOIDS Body Dysmorphic Disorder Digital Image Manipulation Dermatological Patient Education Authentic Skin Health
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Structural color from basic principles to emerging applications
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作者 Dohyun Kang Junsuk Rho 《Opto-Electronic Advances》 2025年第4期1-3,共3页
Wenhao Wang and colleagues summarized the latest advancements in structural color research in Opto-Electronic Science. Their review explored the fundamental principles and fabrication methods of structural colors for ... Wenhao Wang and colleagues summarized the latest advancements in structural color research in Opto-Electronic Science. Their review explored the fundamental principles and fabrication methods of structural colors for photonic applications, including anti-counterfeiting, displays, sensors, and printing, along with their practical limitations. Recently, structural colors have received growing interest due to their advantages, including physical and chemical robustness, ecofriendliness, tunability, and high-resolution color. 展开更多
关键词 structural colors anti counterfeiting SENSORS DISPLAYS structural color nanofabrication PRINTING optical applications
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RED,WHITE AND BLACK:METHODOLOGIES FOR UNDERSTANDING COLOR SYMBOLISM IN MESOPOTAMIAN MAGIC AND RITUAL
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作者 Shiyanthi Thavapalan 《Journal of Ancient Civilizations》 2025年第1期1-23,113,共24页
The color cluster red,black and white occurs in the artistic,ritual and magical activities of virtually all cultures around the world,suggesting their preeminence in human symbolic thought.Among the various explanatio... The color cluster red,black and white occurs in the artistic,ritual and magical activities of virtually all cultures around the world,suggesting their preeminence in human symbolic thought.Among the various explanations that have been brought forth to account for the special status of these three colors are:1)evolutionary/ecological arguments,drawing support from vision science,perceptual philosophy and primate biology;2)cognitive arguments,which pay attention to how human beings categorize and create meaning out of perceptual experiences;3)linguistic arguments,as these are the earliest lexicalized color words in most languages;4)and diverse socio-cultural arguments.This paper will explore the manifestation of red,black and white–both in concrete terms,through the use and manipulation of materials,as well as abstract ideas–in Assyrian and Babylonian magical and ritual activities.It will highlight how meaning is created and communicated by relating colors to natural and supernatural phenomena and will further attempt to provide a methodological framework for the analysis of color symbolism. 展开更多
关键词 Akkadian color terminology color symbolism Mesopotamian magic and ritual MATERIALITY SEMIOTICS solid metaphors
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Maize plastid terminal oxidase(ZmPTOX)regulates the color formation of leaf and kernel by modulating plastid development
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作者 Qiang Huang Zhuofan Zhao +11 位作者 Xiaowei Liu Xin Yuan Ruiqing Zhao Qunkai Niu Chuan Li Yusheng Liu Danfeng Wang Tao Yu Hongyang Yi Chengming Yang Tingzhao Rong Moju Cao 《Journal of Genetics and Genomics》 2025年第3期441-445,共5页
Carotenoids are the largest group of natural pigments responsible for the yellow,orange,and red colors in plant kernels,fruits,and leaves(Gupta and Hirschberg,2021).In plants,carotenoids are involved in manybiological... Carotenoids are the largest group of natural pigments responsible for the yellow,orange,and red colors in plant kernels,fruits,and leaves(Gupta and Hirschberg,2021).In plants,carotenoids are involved in manybiological processes,such as acting as accessory light-harvesting pigments in photosynthesis,participating in photoprotection,and serving as precursors for the hormones abscisic acid(ABA)and strigolactones(Ruiz-Sola and Rodriguez-Concepcion,2012). 展开更多
关键词 leaf color kernel color PHOTOPROTECTION photosynthesis maize plastid terminal oxidase plastid development zmptox abscisic acid aba
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Ishihara color plates utilized as an assessment for simultanagnosia in posterior cortical atrophy:A case report
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作者 Francesco Pellegrini Alessandra Cuna +5 位作者 Mutali Musa Fabiana D’Esposito Rosa Giglio Daniele Tognetto Caterina Gagliano Marco Zeppieri 《World Journal of Clinical Cases》 2025年第27期99-104,共6页
BACKGROUND Simultanagnosia is a neurological disorder that impairs an individual's ability to perceive more than one object at a time visually.While the individual may acknowledge the presence of multiple objects ... BACKGROUND Simultanagnosia is a neurological disorder that impairs an individual's ability to perceive more than one object at a time visually.While the individual may acknowledge the presence of multiple objects in his field of view,he cannot generally summarize the overall percept.CASE SUMMARY We describe a case of simultanagnosia in Posterior Cortical Atrophy,evidenced by the Ishihara color test.A 54-year-old woman complained of reading problems despite normal visual acuity and a structural eye exam.The patient failed to identify any of the Ishihara color plates in either eye despite adequate naming of colors.Automated visual field testing showed a homonymous hemianopia.Structural and functional neuroimaging and cerebrospinal fluid analysis were consistent with posterior cortical atrophy.CONCLUSION Simultanagnosia can be tested with the Ishihara pseudoisochromatic plates because the recognition of embedded number patterns in the test requires appreciation of a collection of individual stimuli. 展开更多
关键词 Simultanagnosia Posterior cortical atrophy color vision Benson syndrome Ishihara color plates Case report
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Angle-robust plasmonic color printing of deep subwavelength nanopixelated sodium metasurfaces
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作者 Jie Liang Yurui Qu +6 位作者 Huizhen Zhang Yuhan Yang Yang Wang Yuchen Zhang Zhenda Lu Shining Zhu Lin Zhou 《Advanced Photonics Nexus》 2025年第1期50-58,共9页
Plasmonic colors are attracting attention for their subwavelength small size,vibrant hues,and environmental sustainability beyond traditional pigments while suffering from angular and/or polarization dependency due to... Plasmonic colors are attracting attention for their subwavelength small size,vibrant hues,and environmental sustainability beyond traditional pigments while suffering from angular and/or polarization dependency due to distinct excitations of lattice resonances and/or surface plasmon polaritons(SPPs).Here,we demonstrate the sodium metasurface-based plasmonic color palettes with polarization-independent wide-view angle(approximately>〓〓60 deg in experiment and up to〓〓90 deg in theory)and single-particlelevel pixel size(down to∼60 nm)that integrate both pigment-like and structure coloring advantages,fabricated by the templated nanorod-pixelated solidification of wetted liquid metals.Such intriguing performances are mainly attributed to the particle plasmon dominant spectral response by steering the filling profile and thus the interplay between localized surface plasmons and SPPs.Combining low material cost,potentially scalable manufacturing process,and pronounced optical performance,the proposed sodium-based metasurfaces will provide a promising route for advanced color information technology. 展开更多
关键词 angle-robust plasmonic color sodium metal deep subwavelength nanopixel localized surface plasmon resonance color printing.
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Color Fourier single-pixel imaging with random color filter array
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作者 Jialiang Chen Wei Zhu +1 位作者 Le Wang Shengmei Zhao 《Chinese Physics B》 2025年第9期250-259,共10页
Color Fourier single-pixel imaging(FSI)enables efficient spectral and spatial imaging.Here,we propose a Fourier single-pixel imaging scheme with a random color filter array(FSI-RCFA).The proposed method employs a rand... Color Fourier single-pixel imaging(FSI)enables efficient spectral and spatial imaging.Here,we propose a Fourier single-pixel imaging scheme with a random color filter array(FSI-RCFA).The proposed method employs a random color filter array(RCFA)to modulate Fourier patterns.A three-step phase-shifting technique reconstructs the Fourier spectrum,followed by an RCFA-based demosaicing algorithm to recover color images.Compared to traditional color FSI based on Bayer color filter array schemes(FSI-BCFA),our approach achieves superior separation between chrominance and luminance components in the frequency domain.Simulation results demonstrate that the FSI-RCFA method achieves a lower mean squared error(MSE),a higher peak signal-to-noise ratio(PSNR),and superior noise resistance compared to FSI-BCFA,while enabling direct single-channel pixel measurements for targeted applications such as agricultural defect detection. 展开更多
关键词 color single-pixel imaging Fourier single-pixel imaging random color filter array demosaicing algorithm noise resistance
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High color quality laser-driven white lighting enabled by reflective bicolor phosphor-in-glass film converter
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作者 Yun Mou Ben Tian +6 位作者 Xin Liu Jiuzhou Zhao Xinyuan Wang Deyi Chen Jian Xu Xinzhong Wang Yang Peng 《Journal of Rare Earths》 2025年第9期1844-1851,共8页
All-inorganic reflective phosphor-in-glass film(PiGF) converter has garnered widespread attentions for high brightness laser-driven white lighting,while its poor color quality and low luminescence stability have been ... All-inorganic reflective phosphor-in-glass film(PiGF) converter has garnered widespread attentions for high brightness laser-driven white lighting,while its poor color quality and low luminescence stability have been inevitable roadblocks.Herein,the bicolor PiGF containing green-emitting Y3Al3.08Ga1.92O12:Ce3+(YAGG) and red-emitting CaAlSiN_(3):Eu^(2+)(CASN) phosphors bonded on Al2O3substrate was prepared for enabling high color quality laser-driven white lighting in reflective configuration.The bicolor PiGF has high quantum efficiency and good structure stability.By optimizing the CASN content,PiGF thickness and Al_(2)O_(3) content,the reflective bicolor PiGF based white laser diode(LD)displays good luminescence performance with a luminous flux of 451.5 lm and a luminous efficacy of142.3 lm/W and high color quality with a color rendering index(CRI) of 85.3 and a correlated color temperature(CCT) of 5177 K under the incident laser power of 3.15 W,and still has excellent luminescence and color stabilities(CRI and CCT) under the continuous laser excitation of 5.61 W,attributed to the good thermal conductivity and high reflectivity of Al_(2)O_(3) substrate and scattering enhancement effect of Al_(2)O_(3) particles.It can be foreseen that the reflective bicolor PiGF converter provides a promising strategy for enabling high quality laser-driven white lighting. 展开更多
关键词 Laser-driven white lighting Phosphor-in-glass film Bicolor reflective phosphor converter color quality Optical performance Rare earths
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Structural Color Dynamic Graphics Display Based on Microlens Array 被引量:1
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作者 LI Xue-han LIU Ling-zhi +1 位作者 HUANG Min LI Xiu 《印刷与数字媒体技术研究》 北大核心 2025年第2期162-168,共7页
It is of great scientific significance to construct a 3D dynamic structural color with a special color effect based on the microlens array.However,the problems of imperfect mechanisms and poor color quality need to be... It is of great scientific significance to construct a 3D dynamic structural color with a special color effect based on the microlens array.However,the problems of imperfect mechanisms and poor color quality need to be solved.A method of 3D structural color turning on periodic metasurfaces fabricated by the microlens array and self-assembly technology was proposed in this study.In the experiment,Polydimethylsiloxane(PDMS)flexible film was used as a substrate,and SiO2 microspheres were scraped into grooves of the PDMS film to form 3D photonic crystal structures.By adjusting the number of blade-coated times and microsphere concentrations,high-saturation structural color micropatterns were obtained.These films were then matched with microlens arrays to produce dynamic graphics with iridescent effects.The results showed that by blade-coated two times and SiO2 microsphere concentrations of 50%are the best conditions.This method demonstrates the potential for being widely applied in the anticounterfeiting printing and ultra-high-resolution display. 展开更多
关键词 Structural color Microlens array Dynamic graphics display Moirémagnification Optical anti-counterfeiting
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Manifestation of Color Confinement in the YY Model for Atomic Nuclei
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作者 Hongguang Yang Weidong Yang 《Journal of Modern Physics》 2020年第12期1999-2010,共12页
In this paper, a manifestation of the well-known color confinement from the QCD (quantum chromodynamics) in the newly developed YY model for the atomic nucleus is presented. There is a wonderful correspondence between... In this paper, a manifestation of the well-known color confinement from the QCD (quantum chromodynamics) in the newly developed YY model for the atomic nucleus is presented. There is a wonderful correspondence between the structural requirements from the YY model and some elementary properties of the color dynamics from QCD. The open questions in the YY model, namely the holding forces for triple nodes and for pairing space links, are exactly covered by the three-color compensation or by the paired color anti-color balance. We will see what colors and anti-colors do mean in the YY model, how up quarks and down quarks get assigned a color or anti-color. We will discover some relationships between gluon-based interactions as described in the standard model and pairing space links in the YY model. 展开更多
关键词 Quantum Chromodynamics QCD color Confinement YY Model for Atomic Nucleus Pairing Space Link PSL Triple Space Link TSL colored up Quark colored Down Quark colored Hydrogen Nucleus colored Helium Nucleus colored Helium Isotope Nucleus color Confinement Aggregate State CCAS color-Balanced PSL Tumbling of colored PSLs
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Identification and molecular marker development for peel color gene in melon(Cucumis melo L.) 被引量:1
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作者 Jian Ma Guoliang Yuan +4 位作者 Xinyang Xu Haijun Zhang Yanhong Qiu Congcong Li Huijun Zhang 《Journal of Integrative Agriculture》 2025年第7期2589-2600,共12页
Peel color is an important appearance quality of melons that significantly affects consumer preferences.In this study,a near-isogenic line NIL-G(dark green peel)was generated from B8(grey-green peel)and B15(white peel... Peel color is an important appearance quality of melons that significantly affects consumer preferences.In this study,a near-isogenic line NIL-G(dark green peel)was generated from B8(grey-green peel)and B15(white peel).The F_2 population constructed by crossing NIL-G and B15 was used to study the inheritance pattern of peel color,and bulked-segregant analysis sequencing(BSA-seq)was employed to identify the interval in which the target gene was located.Genetic analysis showed that a dominant gene controls the dark green peel trait at maturity.BSAseq and molecular markers were used to localize the candidate gene in a 263.7 kb interval of chromosome 4,which contained the CmAPRR2 gene with known functions.Moreover,allelic sequence analysis revealed four SNP variations of the CmAPRR2 gene in B15,of which SNP.G614331A was located at the junction of the 6th exon and 6th intron.The G-to-A mutation caused alternative splicing of the transcript of CmAPRR2 in B15,generating two transcripts(CmAPRR2-A and CmAPRR2-B)with premature termination codons.Furthermore,the Kompetitive Allele Specific PCR(KASP)marker,APRR2-G/A,was developed based on this SNP and shown to co-segregate with the peel color phenotype in the F_(2) population.Compared to white-peel B15,the expression level of CmAPRR2 in dark green peel NIL-G was higher at each growth stage.Therefore,CmAPRR2 may be the key gene controlling the fruit color of melons.This study identified a novel allelic variant of CmAPRR2 that leads to white peel formation in mature melons.We also provides a theoretical basis for further research on the gene regulatory mechanism of melon peel colors,which promotes using molecular marker-assisted selection to modify melon peel colors in the future. 展开更多
关键词 MELON BSA-seq MAPPING CmAPRR2 peel color KASP marker
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Dynamic Structural Colors in Helical Superstructures:from Supramolecules to Polymers 被引量:1
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作者 Bo Ji Lang Qin Yan-Lei Yu 《Chinese Journal of Polymer Science》 2025年第3期406-428,共23页
Cholesteric liquid crystals(CLCs)exhibit unique helical superstructures that selectively reflect circularly polarized light,enabling them to dynamically respond to environmental changes with tunable structural colors.... Cholesteric liquid crystals(CLCs)exhibit unique helical superstructures that selectively reflect circularly polarized light,enabling them to dynamically respond to environmental changes with tunable structural colors.This dynamic color-changing capability is crucial for applications that require adaptable optical properties,positioning CLCs as key materials in advanced photonic technologies.This review focuses on the mechanisms of dynamic color tuning in CLCs across various forms,including small molecules,cholesteric liquid crystal elastomers(CLCEs),and cholesteric liquid crystal networks(CLCNs),and emphasizes the distinct responsive coloration each structure provides.Key developments in photochromic mechanisms based on azobenzene,dithienylethene,and molecular motor switches,are discussed for their roles in enhancing the stability and tuning range of CLCs.We examine the color-changing behaviors of CLCEs under mechanical stimuli and CLCNs under swelling,highlighting the advantages of each form.Following this,applications of dynamic color-tuning CLCs in information encryption,adaptive camouflage,and smart sensing technologies are explored.The review concludes with an outlook on current challenges and future directions in CLC research,particularly in biomimetic systems and dynamic photonic devices,aiming to broaden their functional applications and impact. 展开更多
关键词 Structural colors Cholesteric liquid crystals Elastomers Polymer network
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Nanograting‑Based Dynamic Structural Colors Using Heterogeneous Materials
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作者 Jingang Wang Haibo Yu +6 位作者 Jianchen Zheng Yuzhao Zhang Hongji Guo Ye Qiu Xiaoduo Wang Yongliang Yang Lianqing Liu 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期138-151,共14页
Dynamic structuralcolors can change in response todifferent environmental stimuli.This ability remains effectiveeven when the size of the speciesresponsible for the structural coloris reduced to a few micrometers,prov... Dynamic structuralcolors can change in response todifferent environmental stimuli.This ability remains effectiveeven when the size of the speciesresponsible for the structural coloris reduced to a few micrometers,providing a promising sensingmechanism for solving microenvironmentalsensing problems inmicro-robotics and microfluidics.However, the lack of dynamicstructural colors that can encoderapidly, easily integrate, and accuratelyreflect changes in physical quantities hinders their use in microscale sensing applications. Herein, we present a 2.5-dimensionaldynamic structural color based on nanogratings of heterogeneous materials, which were obtained by interweaving a pH-responsive hydrogelwith an IP-L photoresist. Transverse gratings printed with pH-responsive hydrogels elongated the period of longitudinal grating in the swollenstate, resulting in pH-tuned structural colors at a 45° incidence. Moreover, the patterned encoding and array printing of dynamic structuralcolors were achieved using grayscale stripe images to accurately encode the periods and heights of the nanogrid structures. Overall, dynamicstructural color networks exhibit promising potential for applications in information encryption and in situ sensing for microfluidic chips. 展开更多
关键词 Dynamic structural colors Four-dimensional printing PH-RESPONSIVE Nanogrid Heterogeneous materials
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Robust Backstepping Control of a Quadrotor Unmanned Aerial Vehicle under Colored Noises
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作者 Mehmet Karahan 《Computers, Materials & Continua》 SCIE EI 2025年第1期777-798,共22页
Advances in software and hardware technologies have facilitated the production of quadrotor unmanned aerial vehicles(UAVs).Nowadays,people actively use quadrotor UAVs in essential missions such as search and rescue,co... Advances in software and hardware technologies have facilitated the production of quadrotor unmanned aerial vehicles(UAVs).Nowadays,people actively use quadrotor UAVs in essential missions such as search and rescue,counter-terrorism,firefighting,surveillance,and cargo transportation.While performing these tasks,quadrotors must operate in noisy environments.Therefore,a robust controller design that can control the altitude and attitude of the quadrotor in noisy environments is of great importance.Many researchers have focused only on white Gaussian noise in their studies,whereas researchers need to consider the effects of all colored noises during the operation of the quadrotor.This study aims to design a robust controller that is resistant to all colored noises.Firstly,a nonlinear quadrotormodel was created with MATLAB.Then,a backstepping controller resistant to colored noises was designed.Thedesigned backstepping controller was tested under Gaussian white,pink,brown,blue,and purple noises.PID and Lyapunov-based controller designswere also carried out,and their time responses(rise time,overshoot,settling time)were compared with those of the backstepping controller.In the simulations,time was in seconds,altitude was in meters,and roll,pitch,and yaw references were in radians.Rise and settling time values were in seconds,and overshoot value was in percent.When the obtained values are examined,simulations prove that the proposed backstepping controller has the least overshoot and the shortest settling time under all noise types. 展开更多
关键词 Backstepping control colored noises Gaussian noise Lyapunov stability QUADROTOR ROBUSTNESS PID control
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Research on Printing Preferences for Skin Color
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作者 WANG Dan GONG Xu-ping +1 位作者 SHANG Xiao-yu HUANG Min 《印刷与数字媒体技术研究》 北大核心 2025年第1期46-52,共7页
In order to study the preferred skin color for printing images,two CMYK images from ISO 400 and one from iStock,including five skin color images of East Asian females was selected in this study.The images were adjuste... In order to study the preferred skin color for printing images,two CMYK images from ISO 400 and one from iStock,including five skin color images of East Asian females was selected in this study.The images were adjusted with the CMYK printing ink volume variation of the single,double and triple channels in the given 280%total ink limit conditions.A larger number of color vision normal observers were organized to carry out the color preference evaluation experiment,and the selected preferred skin colors were analyzed.The distribution range of the chromaticity values for skin color images were obtained and the results indicated that there are three regions for printing skin color preferences,and the observers have a memory preference for brighter,fairer skin colors in young female and a reddish skin colors in girl,which can provide the guidance for color adjustment of printed skin color images. 展开更多
关键词 Preferred skin color Printing images Total ink limit CMYK ink adjustment
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Study on Color Difference of Color Reproduction of 3D Objects
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作者 GU Chong DENG Yi-qiang 《印刷与数字媒体技术研究》 北大核心 2025年第4期33-38,69,共7页
To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,a... To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,and TL84)on 3D color difference evaluations,50 glossy spheres with a diameter of 2cm based on the Sailner J4003D color printing device were created.These spheres were centered around the five recommended colors(gray,red,yellow,green,and blue)by CIE.Color difference was calculated according to the four formulas,and 111 pairs of experimental samples meeting the CIELAB gray scale color difference requirements(1.0-14.0)were selected.Ten observers,aged between 22 and 27 with normal color vision,were participated in this study,using the gray scale method from psychophysical experiments to conduct color difference evaluations under the four light sources,with repeated experiments for each observer.The results indicated that the overall effect of the D65 light source on 3D objects color difference was minimal.In contrast,D50 and A light sources had a significant impact within the small color difference range,while the TL84 light source influenced both large and small color difference considerably.Among the four color difference formulas,CIEDE2000 demonstrated the best predictive performance for color difference in 3D objects,followed by CMC(1:1),CIE94,and CIELAB. 展开更多
关键词 color difference formula 3D objects Light source Gray scale Normalized residual sum of squares
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Fading on the beach:pigmentation plasticity adjusts coloration to substrate type in coastal Western spadefoot toads
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作者 Léa Lorrain-Soligon Frédéric Robin +3 位作者 Vincent Lelong Sébastien Palier Marko Jankovic and Françis Brischoux 《Current Zoology》 2025年第5期593-602,共10页
Animal species exhibit a wide range of coloration and patterns,which are under strong selection and often linked to individual quality,influencing mate choice,recognition,signaling,and interspecific interactions such ... Animal species exhibit a wide range of coloration and patterns,which are under strong selection and often linked to individual quality,influencing mate choice,recognition,signaling,and interspecific interactions such as predator avoidance.In amphibians,coloration can vary based on individual traits as well as environmental conditions,including the coloration of their environment.In this study,we described the dorsal coloration(body coloration reticulated by dark patches)in 676 Western spadefoot toads(Pelobates cultripes)from the French Atlantic coast,comparing color variations across different substrates.In addition,we assessed color change in 18 toads transferred between bright and dark substrates.We demonstrated that the dorsal coloration varies based on capture locations(beach vs.inland)and associated substrate types(bright vs.dark),suggesting background color matching.We showed more pronounced effects in females,which might reflect varying predation risks.Experimentally,we showed that individuals can rapidly adjust their coloration to match the substrate within 24 h.Rapid color changes in response to substrate type indicate significant pigmentation plasticity.Bright individuals from sandy substrates showed less dorsal background(body)color change than dark inland individuals,while patch coloration responded differently depending on the substrate of origin.These findings highlight the complex interactions between substrate type,sex,and pigmentation plasticity.These interactions have potential costs and benefits,which might be linked to melanin production,which warrant further investigation. 展开更多
关键词 AMPHIBIANS background color matching INLAND PATCHES sex-dependent substrate
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