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Genome-wide association studies reveal QTL hotspots for grain brightness and black point traits in barley 被引量:1
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作者 Yong Jia Sharon Westcott +7 位作者 Tianhua He Lee Anne McFawn Tefera Angessa Camila Hill Cong Tan Xiaoqi Zhang Gaofeng Zhou Chengdao Li 《The Crop Journal》 SCIE CSCD 2021年第1期154-167,共14页
Grain kernel discoloration(KD)in cereal crops leads to down-grading grain quality and substantial economic losses worldwide.Breeding KD tolerant varieties requires a clear understanding of the genetic basis underlying... Grain kernel discoloration(KD)in cereal crops leads to down-grading grain quality and substantial economic losses worldwide.Breeding KD tolerant varieties requires a clear understanding of the genetic basis underlying this trait.Here,we generated a high-density single nucleotide polymorphisms(SNPs)map for a diverse barley germplasm and collected trait data from two independent field trials for five KD related traits:grain brightness(TL),redness(Ta),yellowness(Tb),black point impact(Tbpi),and total black point in percentage(Tbpt).Although grain brightness and black point is genetically correlated,the grain brightness traits(TL,Ta,and Tb)have significantly higher heritability than that of the black point traits(Tbpt and Tbpi),suggesting black point traits may be more susceptible to environmental influence.Using genome-wide association studies(GWAS),we identified a total of 37 quantitative trait loci(QTL),including two major QTL hotspots on chromosomes 4H and 7H,respectively.The two QTL hotspots are associated with all five KD traits.Further genetic linkage and gene transcription analyses identified candidate genes for the grain KD,including several genes in the flavonoid pathway and plant peroxidase.Our study provides valuable insights into the genetic basis for the grain KD in barley and would greatly facilitate future breeding programs for improving grain KD resistance. 展开更多
关键词 BARLEY Black point Grain brightness GWAS Kernel discoloration SNP markers
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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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An Analogy between the Properties of “Dark Energy” and Physical Vacuum Consisting of Quantum Harmonic Oscillators Characterized by Zero-Point Energy
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作者 Liudmila B. Boldyreva 《Journal of Modern Physics》 2019年第1期20-34,共15页
In quantum field theory, the physical vacuum, free from magnetic and electric fields (without regard to gravitational energy), is defined not as an empty space but as the ground state of the field consisting of quantu... In quantum field theory, the physical vacuum, free from magnetic and electric fields (without regard to gravitational energy), is defined not as an empty space but as the ground state of the field consisting of quantum harmonic oscillators (QHOs) characterized by zero-point energy. The aim of this work is to show that such physical vacuum may possess the properties similar to the properties of dark energy: the positive density, the negative pressure, and the possibility of so-called accelerated expansion. In the model discussed, the mass of QHOs determines the positive density of dark energy. The observed electric polarization of physical vacuum in an electric field means the existence of electric dipole moment of QHO, which, in turn, suggests the existence inside the QHO of a repulsive force between unlike charges compensating the attractive Coulomb force between the charges. The existence of such repulsive force may be treated as the existence of omniradial tensions inside every QHO. In terms of hydrodynamics, it means that the vacuum with this property may be regarded as a medium with negative pressure. The electric dipole-dipole interaction of QHOs under some condition may result in the expansion of physical vacuum consisting of QHOs. It is shown also that the physical vacuum consisting of QHOs is a luminiferous medium, and based on this concept the conditions are discussed for the emergence of invisiblity of any objects (in particular, dark matter). The existence of luminiferous medium does not contradict the second postulate of special relativity (the principle of constancy of the velocity of light in inertial systems), if to take into account the interaction of photons with QHOs and with virtual photons (the virtual particles pairs) created by quantum entities that constitute the inertial systems. 展开更多
关键词 dark ENERGY dark MATTER Zero-point ENERGY Quantum Harmonic Oscillator COSMIC Microwave Background
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Quantum Fractals and the Casimir-Dark Energy Duality—The Road to a Clean Quantum Energy Nano Reactor 被引量:1
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作者 M. S. El Naschie 《Journal of Modern Physics》 2015年第9期1321-1333,共13页
Based on Witten’s T-duality and mirror symmetry we show, following earlier work, the fundamental complimentarity of the Casimir energy and dark energy. Such a conclusion opens new vistas in cold fusion technology in ... Based on Witten’s T-duality and mirror symmetry we show, following earlier work, the fundamental complimentarity of the Casimir energy and dark energy. Such a conclusion opens new vistas in cold fusion technology in the wider sense of the word which we tackle via fractal nano technologies leading to some design proposals for a nano Casimir-dark energy reactor. 展开更多
关键词 CASIMIR ENERGY Zero point ENERGY dark ENERGY E-INFINITY THEORY QUANTUM Set THEORY Algebraic QUANTUM Field Cantorian Spacetime Fractal QUANTUM Phase Space Mirror Symmetry Witten’s T-DUALITY
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A Casimir-Dark Energy Nano Reactor Design—Phase One
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作者 Mohamed S. El Naschie 《Natural Science》 2015年第6期287-298,共12页
A phase one design of a new free energy nano reactor is presented. The design is based on a basically topological interpretation of the Casimir effect as a natural intrinsic property of the geometrical topological str... A phase one design of a new free energy nano reactor is presented. The design is based on a basically topological interpretation of the Casimir effect as a natural intrinsic property of the geometrical topological structure of the quantum-Cantorian micro spacetime. In particular we view dark energy, Hawking negative energy, Unruh temperature and zero point vacuum energy as being different sides of the same multi-dimensional coin. This new interpretation compliments the earlier conventional interpretation as vacuum fluctuation or as a Schwinger source and links the Casimir energy to the so-called missing dark energy density of the cosmos. We start with a general outline of the theoretical principle and basic design concepts of a proposed Casimir dark energy nano reactor. In a nutshell the theory and consequently the actual design depend crucially upon the equivalence between the dark energy density of the cosmos and the faint local Casimir effect produced by two sides boundary condition quantum waves. This Casimir effect is then colossally amplified as a one internal quantum wave representing a Hartle-Hawking state vector of the universe pushing from the inside against the boundary of the universe with nothing balancing it from the non-existent outside. This strange situation becomes completely natural and logical when we remember that the boundary of the universe is a one sided M&#246bius like manifold. In view of the present theory, this is essentially what leads to the observed accelerated expansion of the cosmos. As in any reactor, the basic principle in the present design is to produce a gradient so that the excess energy on one side flows to the other side. Thus in principle we will restructure the local topology of space using material nanoscience technology to create an artificial local high dimensionality with a Dvoretzky theorem like 96 percent volume measure concentration. Without going into the intricate nonlinear dynamics and technological detail, it is fair to say that this would lead us to pure, clean, free energy obtained directly from the topology of spacetime via an artificial singularity. Needless to say, the entire design is based completely on the theory of quantum wave dark energy proposed by the present author for the first time in 2011 in a conference held in the Bibliotheca Alexandrina, Egypt and a little later in Shanghai, Republic of China. The quintessence of the present theory is easily explained as the Φ3 intrinsic Casimir topological energy where Φ=?(√5-1)/2 is produced from the zero set Φ of the quantum particle when we extract the empty set quantum wave Φ2 from it and find Φ-Φ2=Φ3 by restructuring space via conducting but uncharged plates similar to that of the classical Casimir experiments. Our proposed preliminary design of this Casimir-spacetime artificial singularity reactor follows in a natural way from the above. 展开更多
关键词 CASIMIR Effect dark ENERGY E-INFINITY Cantorian SPACETIME NANO Reactor AVANT Projet Free ENERGY Zero point Vacuum ENERGY Hartle-Hawking Quantum Wave of the Cosmos
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Hubble Scale Dark Energy Meets Nano Scale Casimir Energy and the Rational of Their T-Duality and Mirror Symmetry Equivalence
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作者 M.S.El Naschie 《World Journal of Nano Science and Engineering》 2015年第3期57-67,共11页
We establish that ordinary energy, Casimir energy and dark energy are not only interlinked but are basically the same thing separated merely by scale and topology. Casimir energy is essentially a nano scale spacetime ... We establish that ordinary energy, Casimir energy and dark energy are not only interlinked but are basically the same thing separated merely by scale and topology. Casimir energy is essentially a nano scale spacetime phenomenon produced by the boundary condition of the two Casimir plates constituting the Casimir experimental set up for measuring the Casimir force. By contrast dark energy is the result of the cosmic boundary condition, i.e. the boundary of the universe. This one sided M?bius-like boundary located at vast cosmic distance and was comparable only to the Hubble radius scales of the universe. All the Casimir energy spreads out until the majority of it reaches the vicinity of the edge of the cosmos. According to a famous theorem due to the Ukrainian-Israeli scientist I. Dvoretzky, almost 96% of the total energy will be concentrated at the boundary of the universe, too far away to be measured directly. The rest of the accumulated Casimir energy density is consequently the nearly 4% to 4.5%, the existence of which is confirmed by various sophisticated cosmic measurements and observations. When all is said and done, the work is essentially yet another confirmation of Witten’s T-duality and mirror symmetry bringing nano scale and Hubble scale together in an unexpected magical yet mathematically rigorous way. 展开更多
关键词 Mirror Symmetry Casimir Energy dark Energy Zero point Vacuum Energy T-DUALITY Nano Scale-Hubble Scale Mobius Holographic Boundary Dvoretzky’s Theorem Banach-Tarski Theorem
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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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Magnetic non-potentiality on the quiet Sun and the filigree 被引量:3
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作者 Meng Zhao Jing-Xiu Wang Chun-Lan Jin Gui-Ping Zhou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2009年第8期933-944,共12页
From the observed vector magnetic fields by the Solar Optical Telescope/ Spectro-Polarimeter aboard the satellite Hinode, we have examined whether or not the quiet Sun magnetic fields are non-potential, and how the G-... From the observed vector magnetic fields by the Solar Optical Telescope/ Spectro-Polarimeter aboard the satellite Hinode, we have examined whether or not the quiet Sun magnetic fields are non-potential, and how the G-band filigrees and Ca II network bright points (NBPs) are associated with the magnetic non-potentiality. A sizable quiet region in the disk center is selected for this study. The new findings by the study are as follows. (1) The magnetic fields of the quiet region are obviously non-potential. The region-average shear angle is 40°, the average vertical current is 0.016A m^-2, and the average free magnetic energy density, 2.7× 10^2erg cm^-3. The magnitude of these non-potential quantities is comparable to that in solar active regions. (2) There are overall correlations among current helicity, free magnetic energy and longitudinal fields. The magnetic non-potentiality is mostly concentrated in the close vicinity of network elements which have stronger longitudinal fields. (3) The filigrees and NBPs are magnetically characterized by strong longitudinal fields, large electric helicity, and high free energy density. Because the selected region is away from any enhanced network, these new results can generally be applied to the quiet Sun. The findings imply that stronger network elements play a role in high magnetic non-potentiality in heating the solar atmosphere and in conducting the solar wind. 展开更多
关键词 SUN magnetic fields -- Sun photosphere -- Sun network bright point
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On the Cosmical Zero Point Energy Density 被引量:1
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作者 Bo Lehnert 《Journal of Modern Physics》 2016年第10期1112-1119,共8页
The frequency spectrum of the cosmical Zero Point Energy (ZPE) and its total density are so far unknown in their details. In the present complementary investigation, a revised theory forms the basis for studies of thi... The frequency spectrum of the cosmical Zero Point Energy (ZPE) and its total density are so far unknown in their details. In the present complementary investigation, a revised theory forms the basis for studies of this concept in two respects. It first applies to the observable universe considered as an entity, as well as to included subregions such as the galaxies with supermassive black holes. Second, experiments are proposed on the maximum Casimir force arising between two metal plates of different materials and with a vanishing air gap in their spacing. This serves the purpose of making an indirect determination of the ZPE energy density in the laboratory, i.e. at the Earth’s orbit. The ZPE energy density is interpreted as dark matter density and its pressure gradient as dark energy force density. 展开更多
关键词 Zero point Energy Casimir Force dark Matter dark Energy
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基于Landsat影像数据的城市热岛效应研究 被引量:3
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作者 邢孔胜 《测绘与空间地理信息》 2022年第2期177-180,共4页
以研究区2001、2009、2013和2018年Landsat影像数据为研究对象,对该地区的地表亮温进行反演计算,并在研究区范围内选取具有明显识别特征的伪不变特征点,且以2013年的亮温影像为参考基准建立回归分析模型,对多时相的地表亮温影像进行归... 以研究区2001、2009、2013和2018年Landsat影像数据为研究对象,对该地区的地表亮温进行反演计算,并在研究区范围内选取具有明显识别特征的伪不变特征点,且以2013年的亮温影像为参考基准建立回归分析模型,对多时相的地表亮温影像进行归一化处理,从而得到可进行对比分析的研究区地表相对温度,然后进行热岛强度等级分级;最后以研究区热岛强度等级分级图为参考,对研究区热岛效应的时空特征进行综合分析,并提出相应的治理措施。 展开更多
关键词 Landsat影像数据 城市热岛效应 亮温反演 伪不变特征点
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Some Consequences of Zero Point Energy
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作者 Bo Lehnert 《Journal of Electromagnetic Analysis and Applications》 2014年第10期319-327,共9页
Both theory and experiments indicate that the vacuum is not a state of empty space, but is populated by electromagnetic fluctuations at a lowest nonzero level, the Zero Point Energy (ZPE). This debouches into consider... Both theory and experiments indicate that the vacuum is not a state of empty space, but is populated by electromagnetic fluctuations at a lowest nonzero level, the Zero Point Energy (ZPE). This debouches into considerable changes of fundamental physics, as shown by a revised quantum electrodynamic theory (RQED) applied to elementary particles, and by a revised ZPE frequency spectrum applied to the expanding universe. The Standard Model based on a vacuum state of empty space is thus replaced by RQED, thereby resulting in massive elementary particles from the beginning, independently of the theory by Higgs. Also the basic properties of the Higgs-like particle detected at CERN can be reproduced by RQED. It further leads to new fundamental results beyond the theories by Dirac and Higgs, such as to a deduced value of the elementary net charge, magnetic confinement of charged particle configurations, intrinsic local particle charges, photon spin with a very small but nonzero photon rest mass, and needle-like particle-wave properties which contribute to the understanding of the photoelectric effect and two-slit experiments. The real macroscopic pressure due to the revised ZPE frequency distribution further influences the dynamics of the expanding universe, by the ZPE photon pressure gradient acting as dark energy, and the ZPE photon energy density acting as dark matter. This results in a model being consistent with the observed scale, the rate of expansion, and the stability of a flat expanding observable universe. 展开更多
关键词 Zero point ENERGY Quantum ELECTRODYNAMICS Standard Model and Beyond EXPandING UNIVERSE dark ENERGY dark MATTER
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On an Intriguing Invention Albert Einstein Made Which Has Gone Unnoticed Hitherto
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作者 Jean-Paul Auffray 《Journal of Modern Physics》 2015年第11期1478-1491,共14页
We retrieve three mysterious sentences Albert Einstein wrote in the early years of his wondrous scientific career. We examine their implications and we suggest that they provide a surprising new basis for Quantum Phys... We retrieve three mysterious sentences Albert Einstein wrote in the early years of his wondrous scientific career. We examine their implications and we suggest that they provide a surprising new basis for Quantum Physics as well as some enlightenment concerning the whereabouts of Dark energy. 展开更多
关键词 EINSTEIN Absolute Measurements Electromagnetic ENERGY M = E/c2 Space points dark ENERGY M. S. El Naschie Quantum METEORITES
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基于双域融合与亮度补偿的室内图像增强算法
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作者 徐耀松 刘翰林 王雨虹 《传感技术学报》 CAS CSCD 北大核心 2023年第1期45-52,共8页
针对室内环境下的图像易存在失真、整体偏暗、点光源区域明暗交接处存在光晕效应、边缘细节丢失等问题,提出一种基于双域融合与点光源亮度补偿模型相结合的室内图像增强算法。该算法首先采用Canny算子边缘检测方法对图像进行分割,区分... 针对室内环境下的图像易存在失真、整体偏暗、点光源区域明暗交接处存在光晕效应、边缘细节丢失等问题,提出一种基于双域融合与点光源亮度补偿模型相结合的室内图像增强算法。该算法首先采用Canny算子边缘检测方法对图像进行分割,区分出明亮区域和非明亮区域,然后使用亮通道先验算法和暗通道先验算法粗算明亮区域和非明亮区域的透射率后进行正则化求解,用含有归一化参数的点光源亮度补偿模型进行最优步长迭代优化透射率,使图像透射率具有自适应调节能力。黄玉川煤矿选煤厂中监控图像具有典型的失真、偏暗、点光源影响大等特点,以此应用背景为例,对所提出的算法进行实验验证,结果表明处理后图片在峰值信噪比(PSNR)平均提高约20%、平均梯度(MG)平均提高约25%、信息熵(IE)平均提高约30%、结构相似度(SSIM)平均提高约25%,在减少图像明暗交接处光晕、细节保持、鲁棒性等方面均有显著提升。 展开更多
关键词 室内图像增强 双域融合 Canny算子边缘检测 光晕效应 点光源亮度补偿模型 正则化 大气散射模型
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一维镜像综合孔径的近场相位校正方法
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作者 黄煜行 李青侠 +3 位作者 李育芳 雷振羽 牛升达 曹志宇 《上海航天(中英文)》 CSCD 2023年第1期70-79,共10页
镜像综合孔径微波辐射成像的原理基于远场条件推导,不适用于近场成像。为了解决近场条件下的镜像综合孔径成像问题,本文推导了近场双天线互相关表达式,发现近场双天线互相关可以表示为远场双天线互相关与近场相位因子的乘积。校正该相... 镜像综合孔径微波辐射成像的原理基于远场条件推导,不适用于近场成像。为了解决近场条件下的镜像综合孔径成像问题,本文推导了近场双天线互相关表达式,发现近场双天线互相关可以表示为远场双天线互相关与近场相位因子的乘积。校正该相位因子后,即可使用反余弦变换进行近场亮温重建,从而解决了近场条件下的成像问题。本文提出了两种基于外部点源的近场相位校正方法,并分别对点源目标及展源目标进行了仿真,仿真结果表明:校正后的亮温重建误差较小,从而验证了这两种方法的有效性。 展开更多
关键词 一维镜像综合孔径(1D-MAS) 近场成像 外部点源 近场相位校正 亮温重建
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基于改进分布估计的算法在井下监控系统中的应用研究
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作者 梁燕华 芦君珂 田训鹏 《中国矿业》 2023年第12期92-99,共8页
视频监控系统在煤矿井下综采工作中应用广泛,而视频监控采集图像质量的高低直接决定工作人员安全和生产工作效率。目前,受井下粉尘、水汽和光源分布不均等因素的影响,采集的图像信息存在雾气较大、图像过曝光和对比度低的问题。传统的... 视频监控系统在煤矿井下综采工作中应用广泛,而视频监控采集图像质量的高低直接决定工作人员安全和生产工作效率。目前,受井下粉尘、水汽和光源分布不均等因素的影响,采集的图像信息存在雾气较大、图像过曝光和对比度低的问题。传统的暗通道先验去雾算法具有计算速度快、修复效果好的优点,广泛应用于井下去雾,但在处理煤矿井下尘雾大、光源分布不均的图像时会导致图像信息大量丢失和光源区域纹理受损等问题。针对这些问题,提出了一种改进透射率分布估计的井下去雾算法。通过利用暗态点光源模型,结合暗通道可信度权值因子和最优暗通道去雾图像,对透射率分布进行改进,对井下有雾图像进行去雾处理。试验结果表明,改进的透射率分布估计去雾算法相较于Retinex算法,峰值信噪比、信息熵、标准差和平均梯度分别提高了16.25%、31.39%、17.17%、48.47%,相较于传统暗通道先验去雾算法分别提高了47.24%、35.24%、21.64%、51.79%。实验数据表明改进的透射率分布估计去雾算法处理后的井下图像纹理细节损失小,对比度和清晰度都得到了有效提升。 展开更多
关键词 煤矿视频监控图像 尘雾图像去雾 暗通道先验 暗态点光源模型 透射率分布估计
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提高车载屏闪点测试可重现性方法研究
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作者 朱创 《汽车电器》 2023年第7期86-89,共4页
使用成像亮度计对防眩显示屏进行闪点测试已经成为共识,然而由于测试重现性的问题,仍然无法制定可操作性的测试规范。本文系统研究基于傅里叶变换的频域分离技术,并对相关的测试条件和设备的影响进行大量的试验对比。试验包括13种不同... 使用成像亮度计对防眩显示屏进行闪点测试已经成为共识,然而由于测试重现性的问题,仍然无法制定可操作性的测试规范。本文系统研究基于傅里叶变换的频域分离技术,并对相关的测试条件和设备的影响进行大量的试验对比。试验包括13种不同闪点值的防眩玻璃、2个不同ppi的显示屏,以及12种不同分辨率的相机镜头的组合,超过10000幅亮度图像。根据这些数据,对影响测试重现性的条件进行优化。依据此实验结果提出完整的闪点测试规范和条件,实现了高可重现性,可以作为汽车行业防眩车载屏闪点测试的标准规范,也可以用于其它需要闪点测试的应用。 展开更多
关键词 车载屏 闪点 防眩 测试 成像亮度计
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车辆超车变道辅助警告灯
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作者 黄立敏 钟原 +1 位作者 何俊华 龚和明 《汽车电器》 2023年第7期29-32,共4页
主动安全是目前汽车驾驶安全技术的重点之一。盲区监测系统是主动安全部分中先进驾驶辅助系统ADAS的一部分。盲区监测系统与驾驶员的人机交互是通过发光灯具来实现的。灯光作为最高效的交互方式,在车身有着广泛的运用。本文将重点介绍... 主动安全是目前汽车驾驶安全技术的重点之一。盲区监测系统是主动安全部分中先进驾驶辅助系统ADAS的一部分。盲区监测系统与驾驶员的人机交互是通过发光灯具来实现的。灯光作为最高效的交互方式,在车身有着广泛的运用。本文将重点介绍盲区监测系统常用灯具--超车变道辅助警告灯SWA和BSD。通过对两种产品的功能布置、光学设计要求、光学设计方案等分析,能够在满足设计要求的同时具有良好的感官体验,实现更好的人机交互。通过现有的结构设计软件和光学设计软件对产品的光学设计单元,如准直透镜单元、偏折花纹单元、扩散花纹单元、反射镜不断优化,最终锁定均匀性较好的方案,为客户提供良好的人机交互,提升主动安全性能。 展开更多
关键词 SWA超车辅助警告灯 BSD盲点监测 眼点 光强 亮度 准直透镜 偏折花纹 扩散花纹
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Hαcounterparts of X-ray bright points in the solar atmosphere
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作者 ZHANG Ping FANG Cheng ZHANG QingMin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第5期907-914,共8页
X-ray bright points(XBPs) are small-scale brightenings in the solar corona.Their counterparts in the lower atmosphere,however,are poorly investigated.In this paper,we study the counterparts of XBPs in the upper chromo... X-ray bright points(XBPs) are small-scale brightenings in the solar corona.Their counterparts in the lower atmosphere,however,are poorly investigated.In this paper,we study the counterparts of XBPs in the upper chromosphere where the Hα line center is formed.The XBPs were observed by the X-ray Telescope(XRT) aboard the Hinode spacecraft during the observing plan(HOP0124) in August 2009,coordinated with the Solar Magnetic Activity Research Telescope(SMART) in the Kwasan and Hida Observatory,Kyoto University.It is found that there are 77 Hα brightenings in the same field of view of XRT,and among 57 XBPs,29 have counterparts in the Hα channel.We found three types of relationship:Types a,b and c,corresponding to XBPs appearing first,Hα brightenings occurring first and no respective correspondence between them.Most of the strong XBPs belong to Type a.The Hα counterparts generally have double-kernel structures associated with magnetic bipoles and are cospatial with the footpoints of the XBP loops.The average lag time is ~3 minutes.This implies that for Type a the heating,presumably through magnetic reconnection,occurs first in the solar upper atmosphere and then goes downwards along the small-scale magnetic loops that comprise the XBPs.In this case,the thermal conduction plays a dominant role over the non-thermal heating.Only a few events belong to Type b,which could happen when magnetic reconnection occurs in the chromosphere and produces an upward jet which heats the upper atmosphere and causes the XBP.About half of the XBPs belong to Type c.Generally they have weak emission in SXR.About 62% Hα brightenings have no corresponding XBPs.Most of them are weak and have single structures. 展开更多
关键词 X射线望远镜 太阳大气 上层大气 内核结构 磁场重联 X-射线 低层大气 观测计划
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木荷种源间光合作用参数分析 被引量:31
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作者 熊彩云 曾伟 +5 位作者 肖复明 曾志光 涂圣勇 江斌 邱凤英 伍艳芳 《生态学报》 CAS CSCD 北大核心 2012年第11期3628-3634,共7页
基于直角双曲线修正模型估算3个不同纬度的木荷种源(开平、太平和永丰种源)光补偿点、饱和点、最大净光合速率等参数,以便为评价不同木荷种源对环境的适应能力和优良种源选择等提供科学依据。结果表明:在3个不同纬度种源中,开平种源具... 基于直角双曲线修正模型估算3个不同纬度的木荷种源(开平、太平和永丰种源)光补偿点、饱和点、最大净光合速率等参数,以便为评价不同木荷种源对环境的适应能力和优良种源选择等提供科学依据。结果表明:在3个不同纬度种源中,开平种源具有最高的净光合速率、最大净光合速率和较高的表观量子效率,且其生长速率最快;太平种源光饱和点最高,但其净光合速率、表观量子效率和最大净光合速率最低,其生长速率也最低;永丰种源具有较高的净光合速率、最大净光合速率和表观量子效率,其生长速率略高于太平种源。3个不同纬度木荷种源中,南部开平种源对当地环境具有较强的适应能力和生长潜力,具有较高的推广应用价值。 展开更多
关键词 木荷 种源 净光合速率 表观光量子速率 光饱和点 光补偿点 暗呼吸速率
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长白山阔叶红松林主要树种光合作用的光响应曲线 被引量:141
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作者 张弥 吴家兵 +3 位作者 关德新 施婷婷 陈鹏狮 纪瑞鹏 《应用生态学报》 CAS CSCD 北大核心 2006年第9期1575-1578,共4页
以叶片光合作用观测资料为基础,利用直角双曲线与非直角双曲线两种方法对长白山阔叶红松林的主要建群树种红松(Pinuskoraiensis)、紫椴(Tiliaamurensis)、蒙古栎(Quercusmongolica)、水曲柳(Fraxinusmandshurica)光合作用的光响应曲线... 以叶片光合作用观测资料为基础,利用直角双曲线与非直角双曲线两种方法对长白山阔叶红松林的主要建群树种红松(Pinuskoraiensis)、紫椴(Tiliaamurensis)、蒙古栎(Quercusmongolica)、水曲柳(Fraxinusmandshurica)光合作用的光响应曲线进行了拟合.结果表明,两种方法拟合结果不同,直角双曲线方法简单,但非直角双曲线的拟合结果更符合生理意义.由直角双曲线拟合得出4个树种的初始量子效率α、最大净光合作用速率Pmax以及暗呼吸Rd大于非直角双曲线的拟合结果,而光补偿点Lcp随树种不同而有差异.两种方法得出4个树种的α、Rd大小顺序相同,分别是α为水曲柳>紫椴>蒙古栎>红松;Rd为水曲柳>蒙古栎>紫椴>红松,但由两种方法得出的Pmax、Lcp值大小顺序有差异. 展开更多
关键词 光合作用 光响应曲线 初始量子效率 最大光合作用速率 光补偿点 暗呼吸
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