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Research on color image matching method based on feature point compensation in dark light environment
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作者 唐华鹏 QIN Danyang +2 位作者 YAN Mengying YANG Jiaqiang ZHANG Gengxin 《High Technology Letters》 EI CAS 2023年第1期78-86,共9页
Image matching refers to the process of matching two or more images obtained at different time,different sensors or different conditions through a large number of feature points in the image.At present,image matching ... Image matching refers to the process of matching two or more images obtained at different time,different sensors or different conditions through a large number of feature points in the image.At present,image matching is widely used in target recognition and tracking,indoor positioning and navigation.Local features missing,however,often occurs in color images taken in dark light,making the extracted feature points greatly reduced in number,so as to affect image matching and even fail the target recognition.An unsharp masking(USM)based denoising model is established and a local adaptive enhancement algorithm is proposed to achieve feature point compensation by strengthening local features of the dark image in order to increase amount of image information effectively.Fast library for approximate nearest neighbors(FLANN)and random sample consensus(RANSAC)are image matching algorithms.Experimental results show that the number of effective feature points obtained by the proposed algorithm from images in dark light environment is increased,and the accuracy of image matching can be improved obviously. 展开更多
关键词 dark light environment unsharp masking(USM) denoising model feature point compensation fast library for approximate nearest neighbor(FLANN) random sample consensus(RANSAC)
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Differential gene expression in the body wall of the sea cucumber(Apostichopus japonicus)under strong lighting and dark conditions
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作者 ZHANG Libin FENG Qiming +4 位作者 SUN Lina FANG Yan XU Dongxue ZHANG Tao YANG Hongsheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第5期54-66,共13页
Sea cucumber, Apostichopus japonicus is very sensitive to light changes. It is important to study the influence of light on the molecular response of A. japonicus. In this study, RNA-seq provided a general overview of... Sea cucumber, Apostichopus japonicus is very sensitive to light changes. It is important to study the influence of light on the molecular response of A. japonicus. In this study, RNA-seq provided a general overview of the gene expression profiles of the body walls of A. japonicus exposed to strong light("light"), normal light("control") and fully dark("dark") environment. In the comparisons of "control" vs. "dark", "control" vs. "light" and "dark" vs."light", 1 161, 113 and 1 705 differentially expressed genes(DEGs) were identified following the criteria of|log2 ratio|≥1 and FDR≤0.001, respectively. Gene ontology analysis showed that "cellular process" and "binding"enriched the most DEGs in the category of "biological process" and "molecular function", while "cell" and "cell part" enriched the most DEGs in the category of "cellular component". And the DEGs were mapped to 214, 41 and229 pathways in the Kyoto Encyclopedia of Genes and Genomes database, and 51, 2 and 57 pathways were significantly enriched, respectively. Light-specific DEGs identified in this study will be important targets for further investigation to establish the biochemical mechanisms involved in the adaption of this sea cucumber to changes in the level of environmental light. 展开更多
关键词 sea cucumber Apostichopus japonicus gene expression dark light body wall
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The Looped Light of the Triple-Slit Real Experiment as a Confirmation for the Extra Dimensions of Quantum Spacetime and the Reality of Dark Energy 被引量:1
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作者 Mohamed S. El Naschie 《Optics and Photonics Journal》 2017年第2期19-26,共8页
Looped light in a recent sophisticated real three-slit experiment is interpreted as a strong justification of the old theoretical Peano-Hilbert spacetime model of Ord and El Naschie. This in turn entails the existence... Looped light in a recent sophisticated real three-slit experiment is interpreted as a strong justification of the old theoretical Peano-Hilbert spacetime model of Ord and El Naschie. This in turn entails the existence of extra fractal dimensions and consequently of real dark energy density in full agreement with previous analysis as well as accurate measurements and observations of COBE, WMAP, and the type 1a supernova. 展开更多
关键词 Looped light dark Energy E-INFINITY Cantorian SPACETIME Peano-Hilbert SPACETIME Model Triple-Slit EXPERIMENT Fractal Kaluza-Klein Theory WMAP Type La Supernova
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A Topological Magueijo-Smolin Varying Speed of Light Theory, the Accelerated Cosmic Expansion and the Dark Energy of Pure Gravity 被引量:8
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作者 Mohamed Salah El Naschie Leila Marek-Crnjac +1 位作者 Mohamed Atef Helal Ji-Huan He 《Applied Mathematics》 2014年第12期1780-1790,共11页
The paper presents a detailed analysis of ordinary and dark energy density of the cosmos based on two different but complimentary theories. First, and starting from the concept of the speed of light being an average o... The paper presents a detailed analysis of ordinary and dark energy density of the cosmos based on two different but complimentary theories. First, and starting from the concept of the speed of light being an average over multi-fractals, we use Magueijo-Smolin’s ingenious revision of Einstein’s special relativity famous formula E = mc2 to a doubly special formula which includes the Planck energy as invariant to derive the ordinary energy density E(O) = mc2/22 and the dark energy density E(D) = mc2(21/22) wheremis the mass andcis the speed of light. Second we use the topological theory of pure gravity to reach the same result thus confirming the correctness of the theory of varying speed of light as well as the COBE, WMAP and Type 1a supernova cosmological measurements. 展开更多
关键词 dark ENERGY QUANTUM GRAVITY VARYING Speed of light THEORY ENERGY of QUANTUM Wave QUANTUM Non-Demolition
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Collective behaviors of suprachiasm nucleus neurons under different light–dark cycles
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作者 顾长贵 张新华 刘宗华 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期98-106,共9页
The principal circadian clock in the suprachiasm nucleus (SCN) regulates the circadian rhythm of physiological and behavioral activities of mammals. Except for the normal function of the circadian rhythm, the ensemb... The principal circadian clock in the suprachiasm nucleus (SCN) regulates the circadian rhythm of physiological and behavioral activities of mammals. Except for the normal function of the circadian rhythm, the ensemble of SCN neurons may show two collective behaviors, i.e., a free running period in the absence of a light-dark cycle and an entrainment ability to an external T cycle. Experiments show that both the free running periods and the entrainment ranges may vary from one species to another and can be seriously influenced by the coupling among the SCN neurons. We here review the recent progress on how the heterogeneous couplings influence these two collective behaviors. We will show that in the case of homogeneous coupling, the free running period increases monotonically while the entrainment range decreases monotonically with the increase of the coupling strength. While in the case of heterogenous coupling, the dispersion of the coupling strength plays a crucial role. It has been found that the free running period decreases with the increase of the dispersion while the entrainment ability is enhanced by the dispersion. These findings provide new insights into the mechanism of the circadian clock in the SCN. 展开更多
关键词 suprachiasm nucleus light--dark cycle free running period entrainment range
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The Light-Dark Dual Universe for the Big Bang and Dark Energy 被引量:2
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作者 Ding-Yu Chung Volodymyr Krasnoholovets 《Journal of Modern Physics》 2013年第7期77-84,共8页
In the proposed light-dark dual universe, the light universe is the observable universe with light and kinetic energy that fueled the Big Bang, and the dark universe without light and kinetic energy has been observed ... In the proposed light-dark dual universe, the light universe is the observable universe with light and kinetic energy that fueled the Big Bang, and the dark universe without light and kinetic energy has been observed as dark energy since about 9 billion years after the Big Bang. The light-dark dual universe started from the zero-energy universe through the four-stage cyclic transformation. Emerging from the zero-energy universe, the four-stage transformation consists of the 11D (dimensional) positive-negative energy dual membrane universe, the 10D positive-negative energy dual string universe, the 10D positive-negative energy dual particle universe, and the 4D (light)-variable D (dark) positive-negative energy dual particle asymmetrical universe. The transformation can then be reversed back to the zero-energy universe through the reverse four-stage transformation. The light universe is an observable four-dimensional universe started with the inflation and the Big Bang, and the dark universe is a variable dimensional universe from 10D to 4D. The dark universe could be observed as dark energy only when the dark universe turned into a four-dimensional universe. The four-stage transformation explains the four force fields in our universe. The theoretical calculated percentages of dark energy, dark matter, and baryonic matter are 72.8. 22.7, and 4.53, respectively, in nearly complete agreement with observed 72.8, 22.7, and 4.56, respectively. According to the calculation, dark energy started in 4.47 billion years ago in agreement with the observed 4.71 ± 0.98 billion years ago. The zero-energy cyclic universe is based on the space-object structures. 展开更多
关键词 Cosmology light UNIVERSE dark UNIVERSE DUAL UNIVERSE Big Bang Inflation Zero-Energy Cyclic UNIVERSE dark ENERGY dark MATTER Baryonic MATTER Force Fields
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The study of fluorescence characteristics and biochemical composition of a marine diatom Thalassiosira pseudonana 3H in light and dark cycles—Ⅱ . The effects of light
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作者 J.J.Cullen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1993年第3期457-464,共8页
The effects of light on the fluorescence characteristics and biochemical composition of a marine diatom Tha-lassiosira pseudonana in light and dark cycles were investigated with semi-continuous culture. The results in... The effects of light on the fluorescence characteristics and biochemical composition of a marine diatom Tha-lassiosira pseudonana in light and dark cycles were investigated with semi-continuous culture. The results indicate that, with the increase of growing light intensity, DCMU enhanced fluorescence yield (Fd/Chl), enhanced fluorescence ratio (Fd/F) , cellular carbohydrate content. carbohydrate/chlorophyll a and carbohydrate/protein ratio increased , but the fluorescence yield and cellular chlorophyll a content decreased; The protein content declined with the increase of light intensity in the range of 10- 100 μmol/ (m2·s) and increased at higher than 100 μmol/ (m2·s). Sampling time during the day had great effect on the relationships between growing light intensity and cellular chlorophyll a , carbohydrate content , carbohydrate/chlorophyll a and carbohydrate/protein ratio. 展开更多
关键词 The study of fluorescence characteristics and biochemical composition of a marine diatom Thalassiosira pseudonana 3H in light and dark cycles The effects of light
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The study of fluorescence characteristics and biochemical composition of a marine diatom Thalassiosira pseudonana 3H in light and dark cyclesI. The effects of nutrients
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作者 Zhu Mingyuan, Yang Xiaolong and J. J. Cullen 1. First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China2. Bigelow Laboratory for Ocean Sciences, U. S. A. 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第4期593-602,共10页
The effects of nutrients on the fluorescence characteristics and biochemical composition of marine diatom Thalassiosira pseudonana 3H in light and dark cycles were investigated with continuous culture. The results sho... The effects of nutrients on the fluorescence characteristics and biochemical composition of marine diatom Thalassiosira pseudonana 3H in light and dark cycles were investigated with continuous culture. The results show that with the increase of nutrient deficiency, the ratio of enhanced fluorescence to fluorescence (Fd/F), cellular chloropyll-a and protein content of the algae decline, but the fluorescence yield (F/Chl) , DCMU enhanced fluorescence yield (Fd/Chl) , cellular carbohydrate content, carbohydrate/Chl, protein/Chl, carbohydrate/protein increase. The changing amplitude of each parameter is different at different nutrition status, sampling time and different light intensity. 展开更多
关键词 The study of fluorescence characteristics and biochemical composition of a marine diatom Thalassiosira pseudonana 3H in light and dark cyclesI The effects of nutrients
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From Darkness to the Light──The 50th Anniversary of Tibet's Peaceful Liberation
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《China Today》 2001年第5期6-7,共2页
关键词 From darkness to the light The 50th Anniversary of Tibet’s Peaceful Liberation
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Calculating the Exact Experimental Density of the Dark Energy in the Cosmos Assuming a Fractal Speed of Light
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作者 Mohamed S. El Naschie 《International Journal of Modern Nonlinear Theory and Application》 2014年第1期1-5,共5页
Fractal speed of light theory is a variation of Magueijo-Smolin varying speed of light (VSL) theoretical modification of Einstein’s energy mass relation. We use this theory to derive an exact value for the missing da... Fractal speed of light theory is a variation of Magueijo-Smolin varying speed of light (VSL) theoretical modification of Einstein’s energy mass relation. We use this theory to derive an exact value for the missing dark energy which is found to be in astonishing agreement with the latest result of the WMAP measurement and the independent supernova analysis. Thus while Einstein’s formula predicts 95.5% more energy than found in highly precise astrophysical measurement, our VSL- based calculation indicates an exact theoretical value of only 4.508497% real energy. Consequently, the exact conjectured missing dark energy must be 95.491502%. By any standards, this is an astounding confirmation for both the cosmological measurement and the VSL theory. 展开更多
关键词 Nonlinear Dynamics Fractals dark Energy Quantum Gravity Varying Speed of light Theory
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Light Speed Expansion and Rotation of a Very Dark Machian Universe Having Internal Acceleration
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作者 U. V. S Seshavatharam S. Lakshminarayana 《International Journal of Astronomy and Astrophysics》 2020年第3期247-283,共37页
We present a Machian model of Quantum Cosmology with full dark matter and light speed expansion and rotation. During galaxy formation and evolution, fraction of dark matter transforms to visible matter with a relation... We present a Machian model of Quantum Cosmology with full dark matter and light speed expansion and rotation. During galaxy formation and evolution, fraction of dark matter transforms to visible matter with a relation of the form, m_vis = constant * (m_dark)<sup>2/3</sup>. Using this relation and replacing MOND’s “critical acceleration” with “current cosmic maximum angular acceleration”, galactic flat rotation speed range of (50 to 500) km/sec can be fitted well. Estimated flat rotation speeds of DD168, Milky Way and UGC12591 are 49.96 km/sec, 199.66 km/sec and 521.75 km/sec respectively. Based on these striking coincidences, it is possible to say that, MOND’s approach is implicitly connected with cosmological estimation of 95% invisible matter. With reference to SPARC data for flat rotation speeds and current cosmic maximum angular acceleration, galactic total mass can be estimated. Considering galactic total mass, galactic visible mass and dark mass can be estimated. Proceeding further, galactic working radii, angular velocity and visible matter density can be estimated. Estimated Milky Way’s effective radius is 293 kpc. Even though, this model is free from “big bang”, “inflation”, “dark energy”, “flatness” and “red shift” issues, at 2.722 K, estimated present Hubble parameter is 66.24 km/sec/Mpc, cosmic radius is 146.3 times of the Hubble radius, angular velocity is 146.3 times lower than the Hubble parameter and cosmic age is 146.3 times of the Hubble age. With future observations and advanced telescopes, it may be possible to see far distant galaxies and very old stars far beyond the current observable cosmic radius. 展开更多
关键词 Planck Scale Machian Universe Speed of light Galactic dark Matter Galactic Visible Mass Galactic Visible Mass Density Cosmic Anisotropy Galactic Internal Acceleration Cosmic Graviton Wavelength
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Looped Light on Dark Energy
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作者 Mohamed S. El Naschie 《Journal of Quantum Information Science》 2017年第2期43-47,共5页
We give a mathematical golden mean distribution based probabilistic confirmation of a recent spectacular experiment with light. The experiment in question is a three-slit variant of the well known two-slit set up of q... We give a mathematical golden mean distribution based probabilistic confirmation of a recent spectacular experiment with light. The experiment in question is a three-slit variant of the well known two-slit set up of quantum mechanics. The outcome of the sophisticated experiment revealed the looped path of light on the quantum scale and consequently the Peano-Hilbert geometry of spacetime, ergo its fractal-Cantorian nature. The mathematics used here on the other hand is the remarkably simple and insightful golden mean probability distribution known from a famous paradox known in social sciences as the voter paradox. 展开更多
关键词 dark Energy the VOTER PARADOX Golden Mean Distribution Looped light the Triple-Slit Experiment Cantorian-Fractal SPACETIME
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日本暗夜星空保护制度的建设及其对我国的启示
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作者 李奇伟 李泓洁 《黑龙江生态工程职业学院学报》 2024年第2期22-28,共7页
暗夜星空保护制度是一项保护美丽星空环境、防治光污染的新兴法律制度。从20世纪80年代以来,日本逐步确立了暗夜星空保护制度,并通过出台政策文件明确了星空保护区设定、照明器具限制使用、费用补偿、行政调查措施等核心规则,有力地提... 暗夜星空保护制度是一项保护美丽星空环境、防治光污染的新兴法律制度。从20世纪80年代以来,日本逐步确立了暗夜星空保护制度,并通过出台政策文件明确了星空保护区设定、照明器具限制使用、费用补偿、行政调查措施等核心规则,有力地提升了暗夜星空保护力度。就我国而言,可以借鉴域外法治经验,依循从地方到中央的立法思路,由星空资源富集区进行先行立法,基于分类管理理念确立暗夜星空保护区设定规则,基于规范与惩治相结合原则完善暗夜星空管理制度。 展开更多
关键词 光污染防治 暗夜星空保护制度 暗夜星空保护区
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基于视觉感知的低对比度图像细节增强方法 被引量:2
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作者 朱雪俊 《现代电子技术》 北大核心 2024年第1期74-77,共4页
由于传统图像细节增强方法存在噪声含量大及失真等问题,为了提升低对比度图像的视觉效果,提出基于视觉感知的低对比度图像细节增强方法。根据人眼视觉感知的亮度掩蔽特性划分图像区域,并设计暗适应函数与明适应函数,分别延长低对比度图... 由于传统图像细节增强方法存在噪声含量大及失真等问题,为了提升低对比度图像的视觉效果,提出基于视觉感知的低对比度图像细节增强方法。根据人眼视觉感知的亮度掩蔽特性划分图像区域,并设计暗适应函数与明适应函数,分别延长低对比度图像灰度值较低、较高区域间隔,实现基于视觉感知的低对比度图像全局增强;以全局增强结果为基础,引入加权自适应局部低对比度增强法,增强低对比度图像的细节,获取最佳低对比度图像细节增强结果。实验结果表明:该方法增强后的低对比度图像保留了图像的边缘及细节,图像更加明亮清晰,显著提升了其视觉效果,同时低对比度图像具备噪声含量小、失真程度小、图像质量高的优势。 展开更多
关键词 视觉感知 低对比度图像 非线性变换 全局低对比度 局部低对比度 暗适应函数 明适应函数 图像增强
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基于角点校准的暗光下桥梁位移监测研究
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作者 赵少杰 黄滏 +1 位作者 张潇婷 马嘉成 《湘潭大学学报(自然科学版)》 CAS 2024年第2期81-91,共11页
基于机器视觉的数字图像方法监测结构物变形具有非接触性等优点,但受到暗光环境及人工标志物变形等因素的影响导致其应用受限.在现有模板匹配测量基础上,提出了暗光环境下基于Harris角点检测校准和Retinex暗光增强网络的桥梁位移监测方... 基于机器视觉的数字图像方法监测结构物变形具有非接触性等优点,但受到暗光环境及人工标志物变形等因素的影响导致其应用受限.在现有模板匹配测量基础上,提出了暗光环境下基于Harris角点检测校准和Retinex暗光增强网络的桥梁位移监测方法和系统,以提高桥梁结构在复杂环境下的位移监测精度.进一步通过试验验证,结果显示10 m距离的暗光环境下桥梁位移监测最大绝对误差小于0.3 mm,在靶标偏转角度在0.6°至1.2°情况下,基于角点校准后的平均精度相比未校准提高了44%,说明该系统具备在暗光环境下进行工程结构位移监测的实用性. 展开更多
关键词 桥梁监测 机器视觉 暗光增强 模板匹配 角点检测
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基于不均匀光照校正和优化透射率的夜间去雾
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作者 陈飞 杨燕 陈阳 《计算机仿真》 2024年第5期172-177,257,共7页
针对夜间有雾天气场景下的光照不均匀、图像不清晰问题,提出了一种基于夜间不均匀光照校正和优化透射率的去雾算法。首先针对光照不均匀问题,使用基于伽马函数的图像自适应校正算法,消除不均匀光照对图像的影响;其次,由于夜间图像大部... 针对夜间有雾天气场景下的光照不均匀、图像不清晰问题,提出了一种基于夜间不均匀光照校正和优化透射率的去雾算法。首先针对光照不均匀问题,使用基于伽马函数的图像自适应校正算法,消除不均匀光照对图像的影响;其次,由于夜间图像大部分颜色较暗,通过改进局部大气光获得大气光值;利用Sigmoid函数融合亮通道与暗通道得到粗透射率,经过联合双边滤波细化,再对光源处透射率进行优化,并使用伽马函数增强得到最终透射率;然后根据大气散射模型得到初步恢复图像;最后经过引导滤波细化,得到最终图像。实验结果表明所提算法在夜间场景中能有效去雾,且能较好的保持图像颜色对比度。 展开更多
关键词 伽马函数 不均匀光照矫正 局部大气光 亮暗通道融合 夜间去雾
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基于暗通道引导滤波和光照校正的煤矿井下图像去雾算法
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作者 盖勇刚 《工矿自动化》 CSCD 北大核心 2024年第6期89-95,共7页
现有煤矿井下图像去雾方法在处理煤矿井下图像时未能在提取图像深层次特征信息的同时进行光照校正,处理后的图像存在细节信息丢失或图像偏暗的问题。提出一种基于暗通道引导滤波和光照校正的煤矿井下图像去雾算法。首先,井下原始图像通... 现有煤矿井下图像去雾方法在处理煤矿井下图像时未能在提取图像深层次特征信息的同时进行光照校正,处理后的图像存在细节信息丢失或图像偏暗的问题。提出一种基于暗通道引导滤波和光照校正的煤矿井下图像去雾算法。首先,井下原始图像通过图像分化模块(IDM)进行双边滤波、光照估计和暗原色处理后得到光照图、暗原色图和光照反射图。然后,对暗原色图进行预处理,作为权重引导参数对光照反射图进行引导滤波,以恢复图像细节特征信息。最后,将光照图作为权重参数对图像进行光照校正和特征提取,通过多次光照校正解决颜色失真问题,同时增加网络深度,进而去除黑暗区域的退化,实现图像细节的重构,从而得到清晰图像。主观评价结果表明:基于暗通道引导滤波和光照校正的煤矿井下图像去雾算法在去除雾气的同时,保留了更多的结构纹理及背景细节,使整个图像更加接近于对应的清晰图像。客观评价结果表明:与次优算法PMS-Net相比,在训练集和测试集上信息熵分别提高0.32和0.11,标准差分别提高3.58和1.89,平均梯度分别提高0.008和0.004,说明所提算法可有效降低煤矿井下图像的雾气。消融实验结果表明,所提算法在测试数据集上的信息熵、标准差、平均梯度均高于其他网络组成模型,说明所提算法去雾效果最好,且能有效保留图像细节和边缘信息。 展开更多
关键词 煤矿井下图像 去雾算法 暗通道引导滤波 光照校正 暗原色处理
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融合暗通道与Retinex算法的水下图像复原研究
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作者 李玉鑫 梁天全 +1 位作者 于会山 侯秀月 《计算机仿真》 2024年第3期162-167,172,共7页
针对水下图像存在细节模糊和色彩失真等问题,基于水下光学成像模型,提出了一种融合暗通道先验和Retinex的方法。首先为避免场景中亮白区域影响,提出一种基于四叉树分解方法改进对背景光的估计,进一步分通道对透射率进行估计,引入自适应... 针对水下图像存在细节模糊和色彩失真等问题,基于水下光学成像模型,提出了一种融合暗通道先验和Retinex的方法。首先为避免场景中亮白区域影响,提出一种基于四叉树分解方法改进对背景光的估计,进一步分通道对透射率进行估计,引入自适应容差补偿机制,根据图像区域的明亮程度自适应修正透射率,并利用改进的导向滤波细化透射率,消除了图像块效应,利用优化的暗通道先验算法对图像进行清晰化处理得到复原图像;其次用Retinex算法提高水下图像对比度以及校正颜色畸变;然后依据复原图像与Retinex算法增强图像的特点进行像素级融合,最终得到复原后的水下图像。为定量评价复原算法,选取了信息熵、平均梯度和UIQM定量化评价因子。实验结果表明,所提算法在主观及客观评价方面均优于对比算法,为后续水下目标探测提供了研究基础。 展开更多
关键词 图像处理 水下图像复原 背景光估计 图像融合 暗通道先验
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微藻光—暗联合发酵制氢固碳效果及经济效益评价
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作者 韩飞 赵青云 +2 位作者 黄煜鸿 焦永刚 尤占平 《天然气工业》 EI CAS CSCD 北大核心 2024年第5期177-186,共10页
微藻能源是最具潜力的第三代生物质能源,将废物处理的微藻用于制氢,能够在增强废物资源化利用的同时提升生物制氢的经济效益与环境效益。为优化微藻生物制氢的方式并提升生产效益,基于光伏供能情境,采用光—暗发酵相结合的方式进行了微... 微藻能源是最具潜力的第三代生物质能源,将废物处理的微藻用于制氢,能够在增强废物资源化利用的同时提升生物制氢的经济效益与环境效益。为优化微藻生物制氢的方式并提升生产效益,基于光伏供能情境,采用光—暗发酵相结合的方式进行了微藻生物氢的制取,并分析了不同光—暗联合下微藻的制氢效果和固碳减排效果,最后核算了废物处理产生的经济效益和生物制氢的生产潜力。研究结果表明:①微藻光发酵制氢具有较好的固碳减排效果,每生产1 kg氢气,光发酵的固碳减排量为0.89 kgCO_(2),相较于暗发酵高0.46 kgCO_(2);②暗发酵制氢具有较好的经济效益,每生产1 kg氢气,暗发酵制氢的经济效益为61.56元,相较于光发酵高61.01元;③将光—暗发酵相结合,单个周期可生产41.23 kg氢气,实现固碳减排54.61 kgCO_(2),产生经济效益为2560.52元。结论认为:①采用TP5类(自养时间7 d、异养时间9 d,微藻最终浓度为54 g/L)周期下微藻增殖量进行的光—暗发酵制氢,实现了固碳减排与经济效益并存,相比于其他组合具有更好的生产效果,更适合用于规模化扩大生产;②光—暗发酵联合制氢是基于微藻增殖所进行的,应依据藻种特性优化制氢环境,对制氢比例与制氢方式做出调整,以加强微藻生物质能源开发,不断扩展微藻生物制氢的发展前景。 展开更多
关键词 微藻 光—暗发酵 生物制氢 能源 固碳减排 经济效益 废物处理
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基于半监督学习和支持向量机的铀矿分选方法研究
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作者 吴泽彬 陈锐 《金属矿山》 CAS 北大核心 2024年第3期229-236,共8页
为了识别可冶炼铀矿石,提高资源利用率,采用X射线透射技术,并结合半监督学习算法—ITSVM,实现对铀矿的智能分选。同时为进一步优化模型性能,引入了亮暗校正方法以解决图像噪声问题,该方法通过归一化处理,将噪声图片中的每个像素点进行映... 为了识别可冶炼铀矿石,提高资源利用率,采用X射线透射技术,并结合半监督学习算法—ITSVM,实现对铀矿的智能分选。同时为进一步优化模型性能,引入了亮暗校正方法以解决图像噪声问题,该方法通过归一化处理,将噪声图片中的每个像素点进行映射,从而提升图像质量。通过改进的直线凹点检测与切割算法和切片方法,攻克了支持向量机对多目标分类任务的难题,该算法通过检测像素点相对于直线的位置和距离,利用约束条件判断凹点,采用最小距离切割方法获得对应的切割线,再通过切片的方法将多目标检测问题转化为多个独立的单一目标检测问题。通过综合这2种优化方法,最终建立了ITSVM铀矿分选模型。通过X射线投射技术收集到的2000张铀矿图片对该模型进行训练测试,并与SVM和TSVM模型进行结果对比。结果表明,经过亮暗校正,模型在检测铀矿的准确性方面提升了2.9个百分点;通过使用改进的直线凹点检测与切割算法和切片方法,使ITSVM模型具备多目标检测功能,模型对多目标铀矿图片检测的准确性达到95.7%;在测试集上,ITSVM模型检测铀矿的准确性达到97.3%。相比于SVM和TSVM,ITSVM在检测铀矿的准确性和持续优化模型方面具有更大优势,实验结果验证了ITSMV模型在铀矿分选领域的可行性。 展开更多
关键词 半监督学习 ITSVM 亮暗校正 改进的直线凹点检测与切割算法
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