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Strategies for Applying LED Lights in Night Space Lighting for Bridges
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作者 Yingling Dai Qinghua Zhao 《Journal of World Architecture》 2024年第3期57-62,共6页
LED lights have been widely used in urban night space lighting in recent years as they are small,energy-saving,and efficient.This article explores the use of LEDs in bridge night space lighting and their application s... LED lights have been widely used in urban night space lighting in recent years as they are small,energy-saving,and efficient.This article explores the use of LEDs in bridge night space lighting and their application strategies.The aim is to offer valuable insights and references for urban planners and bridge lighting designers in China.By advancing the application of LED technology in bridge night lighting,the goal is to enhance the city’s nighttime ambiance,making the bridge an iconic landmark and a defining feature of the city. 展开更多
关键词 Bridge night space lighting lED application color band and gradient Artistic value Online publication:July 11 2024
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HB-Continuous Mappings in L-Topological Space
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作者 Najah A. AlSaedi 《Advances in Pure Mathematics》 2024年第5期333-353,共21页
In this paper, we introduce and study the notion of HB-closed sets in L-topological space. Then, HB-convergence theory for L-molecular nets and L-ideals is established in terms of HB-closedness. Finally, we give a new... In this paper, we introduce and study the notion of HB-closed sets in L-topological space. Then, HB-convergence theory for L-molecular nets and L-ideals is established in terms of HB-closedness. Finally, we give a new definition of fuzzy H-continuous [1] which is called HB-continuity on the basis of the notion of H-bounded L-subsets in L-topological space. Then we give characterizations and properties by making use of HB-converges theory of L-molecular nets and L-ideals. 展开更多
关键词 l-Topological space HB-Closed Set H-Bounded Set HB-Continuous Mappings HB-Convergence l-Molecular Nets l-Ideals
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Space Color Design of Medical and Nursing Institutions Based on Adaptive Aging Characteristics
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作者 WANG Jiang WANG Jie 《Journal of Landscape Research》 2023年第3期13-16,26,共5页
With the acceleration of China’s aging process and the rapid development of social economy,the government’s strong support for the integration of medical and nursing has made the construction of medical and nursing ... With the acceleration of China’s aging process and the rapid development of social economy,the government’s strong support for the integration of medical and nursing has made the construction of medical and nursing buildings more efficient.At the same time,the need for old-age care is more diversified and hierarchical,and the life cycle is more obvious.Designing an aging color environment for the elderly with different visual abilities in medical care buildings has become a problem for investors,operators and designers.This paper takes the indoor color of medical and nursing buildings as the research object,and combines the characteristics of the elderly’s visual acuity and the ratio and efficacy of indoor colors to investigate two high-end medical and nursing institutions in Beijing and Nanjing.Based on the physical,psychological and behavioral needs,this paper explores the appropriate aging color design method for the living space of the elderly in the medical institutions,aiming to make a meagre effort for the in-depth research and practice of indoor environment design of medical institutions in the future. 展开更多
关键词 Medical care space Elderly-oriented color design
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IAACS: Image aesthetic assessment through color composition and space formation
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作者 Bailin YANG Changrui ZHU +3 位作者 Frederick WBLI Tianxiang WEI Xiaohui LIANG Qingxu WANG 《Virtual Reality & Intelligent Hardware》 2023年第1期42-56,共15页
Background Determining how an image is visually appealing is a complicated and subjective task. This motivates the use of a machine-learning model to evaluate image aesthetics automatically by matching the aesthetics ... Background Determining how an image is visually appealing is a complicated and subjective task. This motivates the use of a machine-learning model to evaluate image aesthetics automatically by matching the aesthetics of the general public. Although deep learning methods have successfully learned good visual features from images,correctly assessing the aesthetic quality of an image remains a challenge for deep learning. Methods To address this, we propose a novel multiview convolutional neural network to assess image aesthetics assessment through color composition and space formation(IAACS). Specifically, from different views of an image––including its key color components and their contributions, the image space formation, and the image itself––our network extracts the corresponding features through our proposed feature extraction module(FET) and the Image Net weight-based classification model. Result By fusing the extracted features, our network produces an accurate prediction score distribution for image aesthetics. The experimental results show that we have achieved superior performance. 展开更多
关键词 Image aesthetic assessment color composition space formation Deep learning
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Performance evaluation of wavelet scattering network in image texture classification in various color spaces 被引量:2
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作者 伍家松 姜龙玉 +2 位作者 韩旭 Lotfi Senhadji 舒华忠 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期46-50,共5页
The optimized color space is searched by using the wavelet scattering network in the KTH_TIPS_COL color image database for image texture classification. The effect of choosing the color space on the classification acc... The optimized color space is searched by using the wavelet scattering network in the KTH_TIPS_COL color image database for image texture classification. The effect of choosing the color space on the classification accuracy is investigated by converting red green blue (RGB) color space to various other color spaces. The results show that the classification performance generally changes to a large degree when performing color texture classification in various color spaces, and the opponent RGB-based wavelet scattering network outperforms other color spaces-based wavelet scattering networks. Considering that color spaces can be changed into each other, therefore, when dealing with the problem of color texture classification, converting other color spaces to the opponent RGB color space is recommended before performing the wavelet scattering network. 展开更多
关键词 wavelet scattering network color texture classification color spaces opponent mechanism
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Low-dimensional multi-spectral space for color reproduction based on nonnegative constrained principal component analysis 被引量:1
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作者 王莹 曾平 +1 位作者 罗雪梅 谢琨 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期486-490,共5页
In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonne... In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonnegative constrained principal component analysis method is proposed to construct a low-dimensional multi-spectral space and accomplish the conversion between the new constructed space and the multispectral space. First, the reason behind the negative data is analyzed and a nonnegative constraint is imposed on the classic PCA. Then a set of nonnegative linear independence weight vectors of principal components is obtained, by which a lowdimensional space is constructed. Finally, a nonlinear optimization technique is used to determine the projection vectors of the high-dimensional multi-spectral data in the constructed space. Experimental results show that the proposed method can keep the reconstructed spectral data in [ 0, 1 ]. The precision of the space created by the proposed method is equivalent to or even higher than that by the PCA. 展开更多
关键词 spectral color science nonnegative constrained principal component analysis low-dimensional spectral space nonlinear optimization multi-spectral images spectral reflectance
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结合主动光源和改进YOLOv5s模型的夜间柑橘检测方法 被引量:2
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作者 熊俊涛 霍钊威 +4 位作者 黄启寅 陈浩然 杨振刚 黄煜华 苏颖苗 《华南农业大学学报》 CAS CSCD 北大核心 2024年第1期97-107,共11页
【目的】解决夜间环境下遮挡和较小柑橘难以准确识别的问题,实现采摘机器人全天候智能化作业。【方法】提出一种结合主动光源的夜间柑橘识别方法。首先,通过分析主动光源下颜色特征不同的夜间柑橘图像,选择最佳的光源色并进行图像采集... 【目的】解决夜间环境下遮挡和较小柑橘难以准确识别的问题,实现采摘机器人全天候智能化作业。【方法】提出一种结合主动光源的夜间柑橘识别方法。首先,通过分析主动光源下颜色特征不同的夜间柑橘图像,选择最佳的光源色并进行图像采集。然后,提出一种夜间柑橘检测模型BI-YOLOv5s,该模型采用双向特征金字塔网络(Bi-FPN)进行多尺度交叉连接和加权特征融合,提高对遮挡和较小果实的识别能力;引入Coordinate attention(CA)注意力机制模块,进一步加强对目标位置信息的提取;采用融入Transformer结构的C3TR模块,在减少计算量的同时更好地提取全局信息。【结果】本文提出的BI-YOLOv5s模型在测试集上的精准率、召回率、平均准确率分别为93.4%、92.2%和97.1%,相比YOLOv5s模型分别提升了3.2、1.5和2.3个百分点。在所采用的光源色环境下,模型对夜间柑橘识别的正确率为95.3%,相比白光环境下提高了10.4个百分点。【结论】本文提出的方法对夜间环境下遮挡和小目标柑橘的识别具有较高的准确性,可为夜间果蔬智能化采摘的视觉精准识别提供技术支持。 展开更多
关键词 柑橘 夜间检测 主动光源 双向特征金字塔网络 YOlOv5s HSV颜色空间
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基于Space L的公共交通网络拓扑结构特性分析 被引量:1
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作者 王天睿 刘国睿 +2 位作者 杨海华 陈文星 温忠海 《黑龙江交通科技》 2023年第11期174-178,共5页
遵循复杂网络建模的一般方法,构建了Space L网络模型。以成都市公共交通网络为例进行了节点度与度分布、平均路径长度、聚集系数、点权和边权等拓扑特征分析。结果表明,在L空间下成都市公交网络的聚集系数大、特征路径长度小,具有典型... 遵循复杂网络建模的一般方法,构建了Space L网络模型。以成都市公共交通网络为例进行了节点度与度分布、平均路径长度、聚集系数、点权和边权等拓扑特征分析。结果表明,在L空间下成都市公交网络的聚集系数大、特征路径长度小,具有典型“小世界特征”;节点度的累积概率分布呈指数变化,表明成都市公交网络是一个随机进化增长网络;从点权边权可以得到高笋塘—火车北站公交站路段可以考虑布局换乘枢纽。基于Space L,从蓄意攻击和随机攻击两个方面分析成都公交网络的鲁棒性,得出保障网络运行安全的关键站点,进而优化城市公交网络和枢纽布局。 展开更多
关键词 公共交通 复杂网络 space l 鲁棒性
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Color Measurement of Segmented Printed Fabric Patterns in Lab Color Space from RGB Digital Images 被引量:7
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作者 Charles Kumah Ning Zhang +1 位作者 Rafiu King Raji Ruru Pan 《Journal of Textile Science and Technology》 2019年第1期1-18,共18页
Colors of textile materials are the first parameter of quality evaluated by consumers and a key component considered in selecting printed fabric. In the textiles industry, digital printed fabric analysis is one of the... Colors of textile materials are the first parameter of quality evaluated by consumers and a key component considered in selecting printed fabric. In the textiles industry, digital printed fabric analysis is one of the basic elements in successfully utilizing a color mechanism scheme and objectively evaluating fabric color alterations. Precise color measurement, however, is mostly used in sample analysis and quality inspection which help to produce reproducible or similar product. It is important that for quality inspection, the color of the product should be measured as a necessary requirement of quality control whether the product is to be accepted or not. Presented in this study is an unsupervised segmentation of printed fabrics patterns using mean shift algorithm and color measurements over the segmented regions of printed fabric patterns. The results established a consistent and reliable color measurement of multiple color patterns and appearance with the established range without any interactions. 展开更多
关键词 color Measurement lAB color space RGB color space Region of INTEREST (ROI) Quality Control
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Deer Body Adaptive Threshold Segmentation Algorithm Based on Color Space 被引量:6
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作者 Yuheng Sun Ye Mu +4 位作者 Qin Feng Tianli Hu He Gong Shijun Li Jing Zhou 《Computers, Materials & Continua》 SCIE EI 2020年第8期1317-1328,共12页
In large-scale deer farming image analysis,K-means or maximum between-class variance(Otsu)algorithms can be used to distinguish the deer from the background.However,in an actual breeding environment,the barbed wire or... In large-scale deer farming image analysis,K-means or maximum between-class variance(Otsu)algorithms can be used to distinguish the deer from the background.However,in an actual breeding environment,the barbed wire or chain-link fencing has a certain isolating effect on the deer which greatly interferes with the identification of the individual deer.Also,when the target and background grey values are similar,the multiple background targets cannot be completely separated.To better identify the posture and behaviour of deer in a deer shed,we used digital image processing to separate the deer from the background.To address the problems mentioned above,this paper proposes an adaptive threshold segmentation algorithm based on color space.First,the original image is pre-processed and optimized.On this basis,the data are enhanced and contrasted.Next,color space is used to extract the several backgrounds through various color channels,then the adaptive space segmentation of the extracted part of the color space is performed.Based on the segmentation effect of the traditional Otsu algorithm,we designed a comparative experiment that divided the four postures of turning,getting up,lying,and standing,and successfully separated multiple target deer from the background.Experimental results show that compared with K-means,Otsu and hue saturation value(HSV)+K-means,this method is better in performance and accuracy for adaptive segmentation of deer in artificial breeding scenes and can be used to separate artificially cultivated deer from their backgrounds.Both the subjective and objective aspects achieved good segmentation results.This article lays a foundation for the effective identification of abnormal behaviour in sika deer. 展开更多
关键词 Artificial breeding color space deer body recognition image segmentation K-MEANS multi-target recognition OTSU
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Combination of effective color information and machine learning for rapid prediction of soil water content
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作者 Guanshi Liu Shengkui Tian +2 位作者 Guofang Xu Chengcheng Zhang Mingxuan Cai 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第9期2441-2457,共17页
Soil water content(SWC)is one of the critical indicators in various fields such as geotechnical engineering and agriculture.To avoid the time-consuming,destructive,and laborious drawbacks of conventional SWC measureme... Soil water content(SWC)is one of the critical indicators in various fields such as geotechnical engineering and agriculture.To avoid the time-consuming,destructive,and laborious drawbacks of conventional SWC measurements,the image-based SWC prediction is considered based on recent advances in quantitative soil color analysis.In this study,a promising method based on the Gaussian-fitting gray histogram is proposed for extracting characteristic parameters by analyzing soil images,aiming to alleviate the interference of complex surface conditions with color information extraction.In addition,an identity matrix consisting of 32 characteristic parameters from eight color spaces is constituted to describe the multi-dimensional information of the soil images.Meanwhile,a subset of 10 parameters is identified through three variable analytical methods.Then,four machine learning models for SWC prediction based on partial least squares regression(PLSR),random forest(RF),support vector machines regression(SVMR),and Gaussian process regression(GPR),are established using 32 and 10 characteristic parameters,and their performance is compared.The results show that the characteristic parameters obtained by Gaussian-fitting can effectively reduce the interference from soil surface conditions.The RGB,CIEXYZ,and CIELCH color spaces and lightness parameters,as the inputs,are more suitable for the SWC prediction models.Furthermore,it is found that 10 parameters could also serve as optimal and generalizable predictors without considerably reducing prediction accuracy,and the GPR model has the best prediction performance(R^(2)≥0.95,RMSE≤2.01%,RPD≥4.95,and RPIQ≥6.37).The proposed image-based SWC predictive models combined with effective color information and machine learning can achieve a transient and highly precise SWC prediction,providing valuable insights for mapping soil moisture fields. 展开更多
关键词 Soil water content(SWC) Digital image Soil color color space Machine learning
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高粱黄色籽粒基因Yellow Seed 2的定位及候选基因分析
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作者 高梽鑫 刚爽 +4 位作者 陆晓春 王平 李政君 王艺威 李金红 《植物遗传资源学报》 CAS CSCD 北大核心 2024年第9期1565-1572,共8页
高粱在我国农业结构调整和酿酒行业中具有重要的作用。籽粒颜色是高粱重要的性状之一,但有关高粱籽粒颜色的研究并不多。本研究观察了高粱黄色籽粒材料GLB41的籽粒发育过程,花后1~16 d为快速生长期,17~24 d进入缓慢膨大期,第25天开始进... 高粱在我国农业结构调整和酿酒行业中具有重要的作用。籽粒颜色是高粱重要的性状之一,但有关高粱籽粒颜色的研究并不多。本研究观察了高粱黄色籽粒材料GLB41的籽粒发育过程,花后1~16 d为快速生长期,17~24 d进入缓慢膨大期,第25天开始进入转色期,绿色逐渐褪去,籽粒颜色由乳白色或苍白色逐渐变成浅黄色,随后颜色加深,40 d后籽粒颜色变为深黄色。利用黄色籽粒GLB41和白色籽粒6E16两个材料构建的群体,使用重测序BSA方法,将控制黄色籽粒性状的基因初定位在1号染色体15.6 Mb区间内,利用3215株分离个体将该基因定位在BR13和P2两个标记之间,区间内有7个候选基因,对这些基因的功能注释进行分析并测序,结果表明GLB41、6E16两个材料中未被报道过的基因Yellow Seed 2(Sobic.001G397900)的编码区内第619~621位插入CTG 3个碱基,导致增加了1个Leu(亮氨酸),第819位C突变为G,导致Cys(半胱氨酸)突变为Trp(色氨酸);第912位C突变为T,但氨基酸序列无变化。因此推测Yellow Seed 2可能参与这两份亲本材料籽粒颜色的形成。本研究为高粱籽粒颜色性状的研究提供了新的基因。 展开更多
关键词 高粱 籽粒颜色 精细定位 候选基因
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基于CIELab色空间法分析光质对葡萄酒颜色的影响
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作者 赵现方 浦宁 +5 位作者 杨雪芹 李发珠 缪博 王丽 南立军 王振吉 《中国果菜》 2024年第9期19-22,共4页
光辐射能够导致葡萄酒颜色变暗、酒体衰老。为延长葡萄酒的货架期,采用蓝光、红光、绿光、棕光和白光分别对葡萄酒进行辐照处理,研究不同光照对葡萄酒的影响。结果发现,蓝光处理后葡萄酒的L^(*)和a^(*)分别下降了20.53和1.282,而b^(*)... 光辐射能够导致葡萄酒颜色变暗、酒体衰老。为延长葡萄酒的货架期,采用蓝光、红光、绿光、棕光和白光分别对葡萄酒进行辐照处理,研究不同光照对葡萄酒的影响。结果发现,蓝光处理后葡萄酒的L^(*)和a^(*)分别下降了20.53和1.282,而b^(*)增加了9.9,表明蓝光对葡萄酒颜色损伤较大。棕光和绿光处理组葡萄酒辐照7 d后,亮度与对照组无显著差异,a^(*)略有增加,红色色调有增加的趋势。损伤最大的是白光处理组,葡萄酒L^(*)和a^(*)分别下降了19.86和6.33,而b^(*)值增加了12.9,辐照7 d后,葡萄酒颜色变暗,呈现棕色色调,出现老化特征。总之,蓝光、白光处理对葡萄酒的颜色影响较大,棕光和绿光影响较小,因此葡萄酒建议使用棕色或绿色玻璃瓶进行贮藏。 展开更多
关键词 光质 葡萄酒 CIElab色空间法 颜色
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Color spaces of safflower (Carthamus tinctorius L.) for quality assessment 被引量:5
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作者 Manfei Xu Chenzhao Du +3 位作者 Na Zhang Xinyuan Shi Zhisheng Wu Yanjiang Qiao 《Journal of Traditional Chinese Medical Sciences》 2016年第3期168-175,共8页
Objective:In this study,safflower(Carthamus tinctorius L.)was taken as a representative example to examine the application of color characteristics to evaluate quality.Methods:A computer vision system was established ... Objective:In this study,safflower(Carthamus tinctorius L.)was taken as a representative example to examine the application of color characteristics to evaluate quality.Methods:A computer vision system was established for the objective and nondestructive assessment of color using image processing algorithms.Color parameters were investigated based on the RGB,L*a*b and HSV color spaces.The content of hydroxysafflor yellow A(HSYA),a major bioactive constituent of safflower,was determined by high-performance liquid chromatography.The relationship between HSYA content and color values was investigated by Pearson correlation analysis.A multiple linear regression model was established to predict the HSYA content from color values.Results:The red color and lightness of safflower were found to be significantly related to HSYA content.The prediction equation obtained by multiple regression was reliable with an R2 value of 0.805(P<.01).Conclusion:The results suggest that the computer vision technique could be used as a promising and non-destructive technology for color measurement and quality evaluation of CHM. 展开更多
关键词 Computer vision Carthamus tinctorius l. color Quality evaluation
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Wide-Band Multi-spectral Space for Color Representation 被引量:2
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作者 Kurt Muenger 《Geo-Spatial Information Science》 2003年第2期69-74,共6页
This paper develops a wide-band multi-spectral space for color representationwith Aitken PCA algorithm. This novel mathematical space using the broad-band spectra matchingmethod aims at improving the accuracy of color... This paper develops a wide-band multi-spectral space for color representationwith Aitken PCA algorithm. This novel mathematical space using the broad-band spectra matchingmethod aims at improving the accuracy of color representation as well as reducing costs forprocessing and storing multi-spectral images. The results show that the space can present ourexperimental original spectral spaces (i. e. Munsell color matt and DIN-6164 color chips) with highefficiency, and that the spanning space with three eigenvectors can present the original space atmore than 98% CSCR, and when 5 eigenvectors are used it can cover almost the whole o-riginal spaces. 展开更多
关键词 color representation METAMERISM wide-band multispectral space PCA(principal component analysis)
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A Study on the Influence of Luminance L* in the L*a*b* Color Space during Color Segmentation 被引量:1
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作者 Rodolfo Alvarado-Cervantes Edgardo M. Felipe-Riveron +1 位作者 Vladislav Khartchenko Oleksiy Pogrebnyak 《Journal of Computer and Communications》 2016年第3期28-34,共7页
In this paper an evaluation of the influence of luminance L* at the L*a*b* color space during color segmentation is presented. A comparative study is made between the behavior of segmentation in color images using onl... In this paper an evaluation of the influence of luminance L* at the L*a*b* color space during color segmentation is presented. A comparative study is made between the behavior of segmentation in color images using only the Euclidean metric of a* and b* and an adaptive color similarity function defined as a product of Gaussian functions in a modified HSI color space. For the evaluation synthetic images were particularly designed to accurately assess the performance of the color segmentation. The testing system can be used either to explore the behavior of a similarity function (or metric) in different color spaces or to explore different metrics (or similarity functions) in the same color space. From the results is obtained that the color parameters a* and b* are not independent of the luminance parameter L* as one might initially assume. 展开更多
关键词 color Image Segmentation CIElAB color space l%MUl%a%MUl%b%MUl% color space color Metrics color Segmentation Evaluation Synthetic color Image Generation
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基于Lab色彩空间的沙尘降质图像增强方法
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作者 牛宏侠 张鸿铸 《液晶与显示》 CAS CSCD 北大核心 2024年第9期1274-1284,共11页
针对沙尘天气导致的数字图像质量大幅下降问题,提出一种基于Lab色彩空间的沙尘降质图像增强方法。将沙尘图像增强分解为偏色校正与细节增强两个步骤处理。偏色校正部分包括去除色偏与亮度拉伸。首先对Lab与YUV色彩空间中的沙尘图像直方... 针对沙尘天气导致的数字图像质量大幅下降问题,提出一种基于Lab色彩空间的沙尘降质图像增强方法。将沙尘图像增强分解为偏色校正与细节增强两个步骤处理。偏色校正部分包括去除色偏与亮度拉伸。首先对Lab与YUV色彩空间中的沙尘图像直方图偏移特点进行了分析,然后提出一种Lab空间偏色校正算法修正直方图偏移,并对初步去除偏色的图像进行亮度拉伸,提升图像对比度。在细节增强部分,引入一种基于饱和度估计透射率的去雾方法进一步增强图像细节信息。实验结果表明,相较于各对比算法,所提算法可以去除不同程度沙尘带来的色偏,且在面对中小型图像时具有最佳的时间性能表现。在量化指标方面,基于无参考感知的图像质量评估标准和基于熵的无参考图像质量评价标准分别提升了3.2%和10.7%。本文方法可以有效去除色偏,还原清晰图像。 展开更多
关键词 图像增强 沙尘图像 lab色彩空间 偏色校正 图像去雾
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Automatic Defect Detection and Grading of Single-Color Fruits Using HSV (Hue, Saturation, Value) Color Space 被引量:1
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作者 Saeideh Gorji Kandi 《Journal of Life Sciences》 2010年第7期39-45,共7页
Machine vision has been recently utilized for quality control of food and agricultural products, which was traditionally done by manual inspection. The present study was an attempt for automatic defect detection and s... Machine vision has been recently utilized for quality control of food and agricultural products, which was traditionally done by manual inspection. The present study was an attempt for automatic defect detection and sorting of some single-color fruits such as banana and plum. Fruit images were captured using a color digital camera with capturing direction of zero degree and under illuminant D65. It was observed that growing decay and time-aging made surface color changes in bruised parts of the object. 3D RGB and HSV color vectors as well as a single channel like H (hue), S (saturation), V (value) and grey scale images were applied for color quantization of the object. Results showed that there was a distinct threshold in the histogram of the S channel of images which can be applied to separate the object from its background. Moreover, the color change via the defect and time-aging is correctly distinguishable in the hue channel image. The effect of illumination, gloss and shadow of 3D image processing is less noticeable for hue data in comparison to saturation and value. The value of H channel was quantized to five groups based on the difference between each pixel value and the H value of a healthy object. The percentage of different degree of defects can be computed and used for grading the fruits. 展开更多
关键词 Machine vision HSV color space FRUIT GRADING defect detection.
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手机直连NGSO卫星业务中扩展L频段频率协调方案研究
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作者 王丽冲 孙晨华 +2 位作者 赵伟松 刘全 卢山 《天地一体化信息网络》 2024年第2期53-62,共10页
在目前非对地静止轨道(NGSO)卫星移动业务用频越来越紧张的趋势下,针对手机直连NGSO卫星业务频率协调工作复杂的问题,首先对手机直连NGSO卫星系统的用频现状及趋势进行分析,其次重点对手机直连NGSO卫星业务在扩展L频段和其他同频空间业... 在目前非对地静止轨道(NGSO)卫星移动业务用频越来越紧张的趋势下,针对手机直连NGSO卫星业务频率协调工作复杂的问题,首先对手机直连NGSO卫星系统的用频现状及趋势进行分析,其次重点对手机直连NGSO卫星业务在扩展L频段和其他同频空间业务的频率协调方案进行分析和研究。通过分析手机直连NGSO卫星业务在扩展L频段的频率协调态势确定需要与之开展频率协调工作的空间业务,基于和每一项空间业务的频率协调方案进行研究并给出协调方案建议,同时还对具体协调方案中涉及的干扰分析计算进行举例。以上研究均可作为手机直连NGSO卫星业务系统开展同频频率协调相关研究及下一步手机直连NGSO卫星关键技术研究等相关工作的参考。 展开更多
关键词 手机直连NGSO卫星业务 扩展l频段 空间业务 频率协调
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分裂的δ-Jordan李color三系的结构
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作者 罗芳 曹燕 《哈尔滨理工大学学报》 CAS 北大核心 2023年第1期137-145,共9页
研究了分裂的δ-Jordan李color三系的结构,定义了分裂的δ-Jordan李color三系的概念,利用分裂的δ-Jordan李color三系的根连通的性质,得到具有对称根系的分裂的δ-Jordan李color三系的分解:T=U+∑[α]∈Λ1/~I[α],其中U是T0的子空间,I[... 研究了分裂的δ-Jordan李color三系的结构,定义了分裂的δ-Jordan李color三系的概念,利用分裂的δ-Jordan李color三系的根连通的性质,得到具有对称根系的分裂的δ-Jordan李color三系的分解:T=U+∑[α]∈Λ1/~I[α],其中U是T0的子空间,I[α]是T的理想,并且满足如果[α]≠[β],那么{I[α],T,I[β]}={I[α],I[β],T}={T,I[α],I[β]}=0。 展开更多
关键词 δ-Jordan李三系 color三系 δ-Jordan李color三系 根空间 分裂
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