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Hydrocarbon Micro-Seepage Detection by Altered Minerals Mapping from Airborne Hyper-Spectral Data in Xifeng Oilfield,China 被引量:3
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作者 Shengbo Chen Ying Zhao +2 位作者 Liang Zhao Yanli Liu Chao Zhou 《Journal of Earth Science》 SCIE CAS CSCD 2017年第4期656-665,共10页
Hydrocarbon micro-seepage can cause oxidation reduction reactions and produce altered minerals in surface sediments and soft. The typical altered minerals mapping by their diagnostic spectral features on hyper-spectra... Hydrocarbon micro-seepage can cause oxidation reduction reactions and produce altered minerals in surface sediments and soft. The typical altered minerals mapping by their diagnostic spectral features on hyper-spectral images is an important tool for the petroleum exploration industry. In this study, the airborne hyper-spectral data were used to investigate the altered minerals induced by hydrocarbon micro-seepages by spectral feature fitting (SFF) in the loess coverage area of Xifeng Oflfield. The results re- veal that the distribution region of the altered minerals induced by hydrocarbon micro-seepage is larger than the known oilfield exploration area. The potential hydrocarbon micro-seepage region was also re- vealed by the distribution of altered minerals besides the known hydrocarbon area. A fast index was pro- posed by the absorption depths of clay and carbonate minerals for assessment of hydrocarbon micro- seepage. And it gave much clearer boundaries for the hydrocarbon micro-seepage in the loess coverage area than those by the altered mineral mapping. In addition, some field samples were analyzed by X-ray diffrac- tion (XRD) and atomic absorption spectrophotometer to validate the results. Within the extents of hydro- carbon micro-seepage, there are lower contents of ferric iron and higher contents of carbonate minerals in these samples. Therefore, it is satisfactory to have the airborne hyper-spectral data to outline the extents of hydrocarbon micro-seepage for further hydrocarbon exploration in the loess coverage area. 展开更多
关键词 hydrocarbon micro-seepage loess coverage airborne hyper-spectral imager altered minerals mapping.
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Study of Spectral Response Characteristics of Oilseed Rape (Brassica napus) to Particulate Matters Based on Hyper-Spectral Technique 被引量:2
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作者 Lijuan Kong Haiye Yu +4 位作者 Zhaojia Piao Meichen Chen Jingmin Dang Lei Zhang Yuanyuan Sui 《Phyton-International Journal of Experimental Botany》 SCIE 2021年第3期1015-1030,共16页
Haze is mainly caused by the suspended particulate matters in the air,of which the particulate matters pollution harms leaf vegetables.In this paper,oilseed rapes at four different growing periods were investigated in... Haze is mainly caused by the suspended particulate matters in the air,of which the particulate matters pollution harms leaf vegetables.In this paper,oilseed rapes at four different growing periods were investigated in a simulated particulate pollution environment.In combination of hyper-spectral technology and micro examination,the response of hyper-spectral characteristics of the leaf to particulate matters was investigated in-depth.The hyperspectral,chlorophyll content,net photosynthetic rate and stomatal conductance of leaf were obtained.The deposition and adsorption of particulate matters on the leaf were observed by Environmental Scanning Electron Microscope(ESEM).Normalized difference vegetation index(NDVI),modified red edge normalized(mNDVI705)and modified red edge simple ratio index(mSR705)were selected as characteristic parameters and the range of 510 nm~620 nm as the sensitive band.16 methods were used to establish the physiological information inversion model.The main results were as follows:Under the influence of particulate matters,the spectral reflectance decreased as a whole.With the increase of leaf age,the phenomenon of blue shift aggravated.The amplitude of yellow and blue edge decreased with overall decreasing vegetation indices.The furrows and irregular band protrusions in leaves were favorable for keeping particulate matters.With longer affecting time and more deposition of particle matters on the leaf,the stomatal opening became smaller.After comparing,principal component regression(PCR)+multiple scatter correction(MSC)+second derivative(SD)+Savitzky-Golay smooth(SG),and partial least square(PLS)+multiple scatter correction(MSC)+first derivative(FD)+Savitzky-Golay smooth(SG)were determined the best method to establish the inversion model of chlorophyll content and net photosynthetic rate respectively.This study may bring novel ideas for the diagnosis and analysis of the physiological response of leaf vegetables under particulate matters pollution using hyper-spectral technology. 展开更多
关键词 Particulate matter hyper-spectral technique oilseed rape chlorophyll content net photosynthetic rate STOMATA inversion model
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High-resolution Hyper-spectral Image Classification with Parts-based Feature and Morphology Profile in Urban Area 被引量:1
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作者 HUANG Yuancheng ZHANG Liangpei LI Pingxiang ZHONG Yanfei 《Geo-Spatial Information Science》 2010年第2期111-122,共12页
High-resolution hyper-spectral image (HHR) provides both detailed structural and spectral information for urban study. However, due to the inherent correlation between spectral bands and within-class variability in th... High-resolution hyper-spectral image (HHR) provides both detailed structural and spectral information for urban study. However, due to the inherent correlation between spectral bands and within-class variability in the data, the data processing of HHR is a challenging work. In this paper, based on spectral mixture analysis theory, a new stack of parts description features were extracted, and then incorporated with a stack of morphology based spatial features. Partially supervised constrained energy minimization (CEM) and unsupervised nonnegative matrix factorization (NMF) were used to extract the part-features. The joint features were then integrated by SVM classifier. The advantages of this method are the representation of physical composition of the urban area by the parts-features and the show of multi-scale structure information by morphology profiles. Experiments with an airborne hyper-spectral data flightline over the Washington DC Mall were performed, and the performance of the proposed algorithm was evaluated in comparison with well-known nonparametric weighted feature extraction (NWFE) and feature selection method. The results shown that the proposed features-joint scheme consistently outperforms the traditional methods, and so can provide an effective option for processing HHR data in urban area. 展开更多
关键词 parts-features CEM NMF morphology profiles hyper-spectral image urban classification
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The recognition of ocean red tide with hyper-spectral-image based on EMD
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作者 赵文仓 韦洪丽 +1 位作者 时长江 姬光荣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第2期137-141,共5页
A new technique is introduced in this paper regarding red tide recognition with remotely sensed hyper-spectral images based on empirical mode decomposition (EMD), from an artificial red tide experiment in the East C... A new technique is introduced in this paper regarding red tide recognition with remotely sensed hyper-spectral images based on empirical mode decomposition (EMD), from an artificial red tide experiment in the East China Sea in 2002. A set of characteristic parameters that describe absorbing crest and reflecting crest of the red tide and its recognition methods are put forward based on general pictre data, with which the spectral information of certain non-dominant alga species of a red tide occurrence is analyzed for establishing the foundation to estimate the species. Comparative experiments have proved that the method is effective. Meanwhile, the transitional area between red-tide zone and non-red-tide zone can be detected with the information of thickness of algae influence, with which a red tide can be forecast. 展开更多
关键词 red tide recognition aerial remote sensing hyper-spectral image empirical mode decomposition (EMD) characteristic parameter
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Spatial-Aware Supervised Learning for Hyper-Spectral Image Classification Comprehensive Assessment
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作者 SOOMRO Bushra Naz XIAO Liang +1 位作者 SOOMRO Shahzad Hyder MOLAEI Mohsen 《Journal of Donghua University(English Edition)》 EI CAS 2016年第6期954-960,共7页
A comprehensive assessment of the spatial.aware mpervised learning algorithms for hyper.spectral image (HSI) classification was presented. For this purpose, standard support vector machines ( SVMs ), mudttnomial l... A comprehensive assessment of the spatial.aware mpervised learning algorithms for hyper.spectral image (HSI) classification was presented. For this purpose, standard support vector machines ( SVMs ), mudttnomial logistic regression ( MLR ) and sparse representation (SR) based supervised learning algorithm were compared both theoretically and experimentally. Performance of the discussed techniques was evaluated in terms of overall accuracy, average accuracy, kappa statistic coefficients, and sparsity of the solutions. Execution time, the computational burden, and the capability of the methods were investigated by using probabilistie analysis. For validating the accuracy a classical benchmark AVIRIS Indian pines data set was used. Experiments show that integrating spectral.spatial context can further improve the accuracy, reduce the misclassltication error although the cost of computational time will be increased. 展开更多
关键词 learning algorithms hyper-spectral image classification support vector machine(SVM) multinomial logistic regression(MLR) elastic net regression(ELNR) sparse representation(SR) spatial-aware
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Radiometric calibration of hyper-spectral imaging spectrometer based on optimizing multi-spectral band selection
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作者 孙立微 叶新 +3 位作者 方伟 何振磊 衣小龙 王玉鹏 《Optoelectronics Letters》 EI 2017年第6期405-408,共4页
Hyper-spectral imaging spectrometer has high spatial and spectral resolution. Its radiometric calibration needs the knowledge of the sources used with high spectral resolution. In order to satisfy the requirement of s... Hyper-spectral imaging spectrometer has high spatial and spectral resolution. Its radiometric calibration needs the knowledge of the sources used with high spectral resolution. In order to satisfy the requirement of source, an on-orbit radiometric calibration method is designed in this paper. This chain is based on the spectral inversion accuracy of the calibration light source. We compile the genetic algorithm progress which is used to optimize the channel design of the transfer radiometer and consider the degradation of the halogen lamp, thus realizing the high accuracy inversion of spectral curve in the whole working time. The experimental results show the average root mean squared error is 0.396%, the maximum root mean squared error is 0.448%, and the relative errors at all wavelengths are within 1% in the spectral range from 500 nm to 900 nm during 100 h operating time. The design lays a foundation for the high accuracy calibration of imaging spectrometer. 展开更多
关键词 calibration SPECTROMETER RADIOMETER fitting optimize interpolation REQUIREMENT ABSOLUTE satisfy reconstructed
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Distance-based separability criterion of ROI in classification of farmland hyper-spectral images
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作者 Tang Jinglei Miao Ronghui +2 位作者 Zhang Zhiyong Xin Jing Wang Dong 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2017年第5期177-185,共9页
The hyper-spectral image contains spectral and spatial information,which increases the ability and precision of objects classification.Despite the classification value of hyper-spectral imaging technology within vario... The hyper-spectral image contains spectral and spatial information,which increases the ability and precision of objects classification.Despite the classification value of hyper-spectral imaging technology within various applications,users often find it difficult to effectively apply in practice because of the effect of light,temperature and wind in outdoor environment.This research presented a new classification model for outdoor farmland objects based on near-infrared(NIR)hyper-spectral images.It involves two steps including region of interest(ROI)acquisition and establishment of classifiers.A distance-based method for quantitative analysis was proposed to optimize the reference pixels in ROI acquisition firstly.Then maximum likelihood(ML)and support vector machine(SVM)were used for farmland objects classification.The performance of the proposed method showed that the total classification accuracy based on the reference pixels was over 97.5%,of which the SVM-M model could reach 99.5%.The research provided an effective method for outdoor farmland image classification. 展开更多
关键词 distance-based separability criterion near-infrared hyper-spectral image ROI farmland image classification
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Algorithm for retrieving surface pressure from hyper-spectral measurements in oxygen A-band 被引量:4
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作者 Hailei Liu Minzheng Duan +1 位作者 Daren L Yan Zhang 《Chinese Science Bulletin》 SCIE EI CAS 2014年第14期1492-1498,共7页
An algorithm for retrieving the surface pressure from oxygen A-band measurements in the future Chinese CO2satellite(CarbonSpec/TanSat)was developed.The ful physical radiative transfer model,vector radiative transfe mo... An algorithm for retrieving the surface pressure from oxygen A-band measurements in the future Chinese CO2satellite(CarbonSpec/TanSat)was developed.The ful physical radiative transfer model,vector radiative transfe model based on successive order of scattering,which i based on the successive order of scattering approach,wa used to simulate the measurements of CarbonSpec/TanSat as well as the kernel matrix in the inversion algorithm,and then the surface pressure and other related atmospheric parameters such as aerosol optical depth(AOD),surface albedo,and temperature were derived through optima estimation theory.Sensitivities of the algorithm to surface albedo,solar zenith angle(SZA),viewing zenith angle(VZA),aerosol type,and AOD were investigated,and the results showed that the absolute error of retrieved surface pressure increases with decreasing surface albedo o increasing SZA and VZA.An accuracy of\4 hPa ove bright surfaces(surface albedo C0.15)could be derived fo various SZAs and viewing geometries.Moreover,the algorithm can simultaneously retrieve the surface albedo AOD,and its vertical distribution indicated by scale 展开更多
关键词 表面压力 求逆算法 光谱测量 波段 氧气 检索 气溶胶光学厚度 地表反照率
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基于动态字典学习的含噪高光谱图像空谱融合
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作者 杨静 赵建斌 +3 位作者 陈路 池浩田 闫涛 陈斌 《计算机应用》 北大核心 2025年第9期2941-2948,共8页
针对传统高光谱图像(HSI)空谱融合算法通常采用静态光谱字典,而字典学习与图像融合过程相分离,对含有噪声的空谱融合任务处理效果不佳的问题,提出一种基于动态字典学习(DDL)的含噪HSI空谱融合算法。该算法采用迭代思想,在融合过程中动... 针对传统高光谱图像(HSI)空谱融合算法通常采用静态光谱字典,而字典学习与图像融合过程相分离,对含有噪声的空谱融合任务处理效果不佳的问题,提出一种基于动态字典学习(DDL)的含噪HSI空谱融合算法。该算法采用迭代思想,在融合过程中动态更新字典原子,从而协作完成空谱融合及噪声去除任务。首先,对输入的HSI进行粗去噪,并利用去噪结果初始化光谱字典;其次,利用上述初始化字典对两幅待融合图像进行稀疏表示,以得到中间融合结果;再次,将中间融合结果反馈给字典学习模块,不断更新字典原子,构造动态光谱字典;最后,通过迭代以上过程得到最终的输出图像。在3个遥感HSI数据集上的仿真实验结果表明,所提算法能够在提升图像空间分辨率的同时有效去除噪声。同时,在真实含噪图像波段上的实验结果表明,所提算法能够有效提高融合图像的视觉质量。在Cuprite Mine数据集上,在高斯噪声方差为0.15且放大倍数为8时,与基于广义张量核范数(GTNN)的方法和先去噪后融合的方法AL-NSSR方法相比,所提算法的峰值信噪比(PSNR)分别提升了32.48%和10.72%。 展开更多
关键词 高光谱图像 空谱融合 噪声 光谱字典学习 迭代稀疏表示
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Global Carbon Monoxide Column Derived from HIRAS-II/FY-3F Satellite Observations
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作者 Minqiang ZHOU Yapeng WANG +5 位作者 Charles ROBERT Xingying ZHANG Lu ZHANG Zhili DENG Chengli QI Pucai WANG 《Advances in Atmospheric Sciences》 2025年第9期1776-1782,共7页
The Hyperspectral Infrared Atmospheric Sounder-II(HIRAS-II)onboard China’s FungYun(FY)-3F meteorological satellite was launched in August 2023.This study presents the first attempt to retrieve the global carbon monox... The Hyperspectral Infrared Atmospheric Sounder-II(HIRAS-II)onboard China’s FungYun(FY)-3F meteorological satellite was launched in August 2023.This study presents the first attempt to retrieve the global carbon monoxide(CO)column from HIRAS-II/FY-3F spectra based on a newly established full-physics algorithm.The CO global columns derived from the HIRAS-II/FY-3F satellite are compared to measurements from the Infrared Atmospheric Sounding Interferometer(IASI)onboard Europe’s MetopB satellite,as both satellites have the same spectral range with a similar overpass time.The correlation coefficient between the IASI/Metop-B and HIRAS-II/FY-3F CO retrievals is about 0.8.The HIRAS-II/FY-3F satellite can capture well the regions with high CO values,e.g.,Africa,North America,and East Asia.The relative difference in the CO global column between HIRAS-II and IASI is 1.2±13.7(1)%,which is within their combined retrieval uncertainty.The CO plumes from the fire emissions in North America between 18 and 23 July 2024 were observed by the HIRAS-II/FY-3F satellite and consistent with the CAMS(Copernicus Atmosphere Monitoring Service)model simulations.Our results show that the HIRAS-II/FY-3F spectra are of good enough quality to provide quantitative observations of global CO column remote sensing observations. 展开更多
关键词 carbon monoxide HIRAS-II/FY-3F hyper-spectral infrared remote sensing wildfire emission
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基于CR-CARS-RF的黑土区土壤有机质含量高光谱估算
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作者 李雨鸿 冯锐 +5 位作者 纪瑞鹏 张霞 武晋雯 于文颖 王婷 李晶 《干旱地区农业研究》 北大核心 2025年第4期203-210,共8页
以辽宁昌图和苏家屯区149个黑土样本为基础,结合地面高光谱数据与实验室土壤有机质(SOM)含量化学测定,系统分析了不同高光谱预处理与建模方法对SOM反演精度的影响,旨在构建快速且精准的SOM含量高光谱反演模型。通过Savitzky-Golay平滑法... 以辽宁昌图和苏家屯区149个黑土样本为基础,结合地面高光谱数据与实验室土壤有机质(SOM)含量化学测定,系统分析了不同高光谱预处理与建模方法对SOM反演精度的影响,旨在构建快速且精准的SOM含量高光谱反演模型。通过Savitzky-Golay平滑法(SG)对光谱数据进行去噪处理后,对比分析了倒数(1/R)、倒数的对数(log(1/R))、一阶导数(FDR)、标准化(SNV)及连续统去除(CR)五种光谱变换方法,并采用皮尔逊相关分析(PCC)和竞争自适应重加权(CARS)算法筛选特征波段,结合偏最小二乘(PLSR)、多元线性回归(MLR)和随机森林(RF)三种建模方法,构建了12种反演模型,对各模型的预测精度进行对比分析。结果表明:(1)CR变换显著增强了光谱与SOM的相关性,2 166 nm之后的128个波段相关系数绝对值超过0.5,最高达0.75;(2)CARS算法有效压缩了特征波段数量,将其控制在全波段的6%以下,与PCC-PLSR和PPC-RF相比,CARS-PLSR和CARS-RF模型预测精度显著提升,其决定系数(R2)分别提高13.4%和14.5%,均方根误差(RMSE)分别降低12.8%和11.9%;(3)非线性RF模型的预测精度最优,与MLR和PLSR相比,其R2分别提升32.1%和3.5%,RMSE分别降低34.9%和4.4%;(4)在12种预测模型中,CR-CARS-RF模型表现最佳,其建模R2为0.91,RMSE为1.76 g·kg^(-1);预测R2为0.79,RMSE为2.49 g·kg^(-1),表明CR-CARS-RF模型具有较高的预测精度和可靠性,可为辽宁黑土区土壤有机质含量的高效精准监测提供有力的技术支撑。 展开更多
关键词 黑土 土壤有机质 高光谱 竞争自适应重加权算法 随机森林模型
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遥感成像技术在口腔疾病诊疗应用的研究进展
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作者 曹梦颖 石蕊 +1 位作者 于瀚雯 刘程程 《国际口腔医学杂志》 北大核心 2025年第1期107-116,共10页
遥感技术是应用传感仪器对远距离目标所辐射和反射的电磁波信息进行收集、处理并最后成像的一种探测技术。近年来,遥感技术与医学交叉融合,在疾病空间分析、精细导航定位和实时医学图像终端等领域展现了广阔的应用前景。作为一种非侵入... 遥感技术是应用传感仪器对远距离目标所辐射和反射的电磁波信息进行收集、处理并最后成像的一种探测技术。近年来,遥感技术与医学交叉融合,在疾病空间分析、精细导航定位和实时医学图像终端等领域展现了广阔的应用前景。作为一种非侵入性的技术,遥感技术不仅可以帮助医生对病灶进行高精度的定位和诊断,还可以结合人工智能等技术手段,对疾病进行预警。本文综合介绍了红外热成像技术、微波成像技术、太赫兹成像技术和高光谱成像技术等遥感成像技术应用于疾病诊疗的原理和优势,并阐述了常见遥感成像技术在龋病病变组织早期的检测、口腔癌边缘和波及范围评估、口腔软硬组织微小变化的探测等口腔诊疗中的应用现状和前景,以期为相关研究提供新思路。 展开更多
关键词 遥感成像技术 红外热成像 微波成像 太赫兹成像 高光谱成像 龋病 口腔癌症 远程医疗
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光谱技术在塑料质量检测中的应用 被引量:1
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作者 刘瑞 冯绍业 《塑料工业》 北大核心 2025年第4期23-28,49,共7页
系统梳理了紫外-可见光谱、红外光谱、拉曼光谱、太赫兹光谱、X射线荧光光谱和高光谱技术的基本原理、优势和挑战,并探讨了其在塑料质量检测领域的应用现状。紫外-可见光谱可应用于塑料制品的结构表征和成分分析,也在劣化评估上有独特... 系统梳理了紫外-可见光谱、红外光谱、拉曼光谱、太赫兹光谱、X射线荧光光谱和高光谱技术的基本原理、优势和挑战,并探讨了其在塑料质量检测领域的应用现状。紫外-可见光谱可应用于塑料制品的结构表征和成分分析,也在劣化评估上有独特应用。红外光谱不仅可对塑料进行结构检测和成分分析,还可进行其性能评估。拉曼光谱在塑料结构表征、成分分析和分类识别上表现突出。太赫兹光谱在塑料结构分析、分类识别和成分分析上应用广泛的同时,在缺陷检测领域也独具优势。X射线荧光光谱在塑料结构、成分和分类上有着广泛应用。高光谱技术因融合成像与光谱,在塑料的高精度分类识别领域优势明显。尽管光谱技术在塑料质量检测领域中具有诸多优势,但也存在一些缺陷和局限性,如易受杂质干扰、稳定性不足、数据解析不准确等。未来的研究方向应结合机器学习和大数据分析的方法,提高光谱技术的智能化和自动化程度,以进一步提升其在复杂塑料材料检测中的应用潜力。 展开更多
关键词 光谱技术 塑料质量检测 紫外-可见光谱技术 红外光谱技术 拉曼光谱技术 太赫兹光谱技术 X射线荧光光谱技术 高光谱技术
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基于数学变换和连续小波变换的苹果园土壤总氮含量高光谱反演
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作者 熊超群 荀咪 +2 位作者 李健 安淼 李国田 《湖北农业科学》 2025年第11期165-170,共6页
为快速测定苹果园土壤总氮(TN)含量,实现精准施肥,以山东省果树研究所天平湖基地苹果园的土壤为研究对象,测定其光谱反射率(R)并进行数学变换(倒数、对数、平方根及一阶微分等)、连续小波变换(Continuous wavelet transform,CWT)及数学... 为快速测定苹果园土壤总氮(TN)含量,实现精准施肥,以山东省果树研究所天平湖基地苹果园的土壤为研究对象,测定其光谱反射率(R)并进行数学变换(倒数、对数、平方根及一阶微分等)、连续小波变换(Continuous wavelet transform,CWT)及数学变换结合CWT处理,采用Pearson相关分析法进行特征提取,基于支持向量回归(Support vector regression,SVR)构建土壤TN含量的高光谱反演模型。结果表明,原始光谱数据经CWT处理后,在2~1~210尺度内,小波系数与土壤TN含量的相关性呈先升高后降低的趋势,中等尺度能有效抑制噪声干扰并增强光谱与TN的相关性,效果显著。数学变换、CWT均能有效挖掘光谱的细节特征,CWT的效果总体上优于数学变换。数学变换结合CWT能显著提升模型反演精度,其中,1/R-CWT-2^(8)模型的反演效果最优(R^(2)=0.73,RMSE=0.12 g/kg,RPD=1.85)。该模型预测的土壤TN含量与实测值的拟合曲线更接近1∶1线,模型预测精度较高。综上,高光谱技术可以作为苹果园土壤TN含量的无损检测手段,数学变换结合CWT构建的高光谱反演模型可以更加精准地预测土壤TN含量。 展开更多
关键词 数学变换 连续小波变换(CWT) 苹果园 土壤 总氮含量 高光谱 反演
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基于CWT-CARS的黄土高原东部陕州区农田表层有机碳含量高光谱反演
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作者 周磊 何秀芹 +3 位作者 贾德伟 刘玉昕 王宁 杨晴晴 《遥感技术与应用》 北大核心 2025年第1期60-68,共9页
土壤有机碳含量高光谱反演对现代农业生产、土壤质量评价具有重要意义。不同的土壤类型高光谱差异较大,探索与不同土壤类型相适应的建模方法,有利于高效准确的反演土壤有机质含量。以黄土高原东部陕州区为研究区,101个农田表层土壤样本... 土壤有机碳含量高光谱反演对现代农业生产、土壤质量评价具有重要意义。不同的土壤类型高光谱差异较大,探索与不同土壤类型相适应的建模方法,有利于高效准确的反演土壤有机质含量。以黄土高原东部陕州区为研究区,101个农田表层土壤样本的光谱数据为研究对象,采用一阶微分(First Derivative,FD)、包络线去除(Continuous Removal,CR)以及连续小波变换(Continuous Wavelet Transform,CWT)等光谱数据预处理方法,并利用竞争适应重加权采样(Competitive Adaptive Reweighted Sampling,CARS)、相关系数法筛选特征波段,进一步比较最小二乘回归(Partial Least Squares Regression,PLSR)、支持向量机(Support Vector Machine,SVM)、反向传播神经网络(Back Propagation Neural Network,BPNN)3种模型反演农田表层土壤有机碳含量的精度。结果表明:①以CARS处理后的特征波段为自变量,3种模型的预测精度(R^(2)=0.67),较以相关系数法提取特征波段为自变量建立的模型均有较大提高,R^(2)提高0.12;②3种模型中,PLSR的平均模拟精度最好(R^(2)=0.68),明显高于SVM(R^(2)=0.53)、BPNN(R^(2)=0.54);③连续小波变换后,不同分解尺度模型模拟精度差别较大。采用CWT26-CARS-PLSR模型预测SOC含量的精度最高(R^(2)=0.91、RMSE=0.75g·kg^(-1)、RPD=3.28)。 展开更多
关键词 黄土高原东部 土壤表层有机碳 高光谱 竞争适应重加权采样 连续小波变换
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黑土土壤水分高光谱特征及反演模型 被引量:64
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作者 姚艳敏 魏娜 +5 位作者 唐鹏钦 李志斌 余强毅 许新国 陈佑启 何英彬 《农业工程学报》 EI CAS CSCD 北大核心 2011年第8期95-100,共6页
应用高光谱技术阐释土壤含水率光谱规律及对土壤含水率进行定量分析,为精准农业地表土壤水分的快速测定提供参考。该文以吉林省黑土土类中的黑土亚类土壤为研究对象,利用ASD FieldSpec FR便携式光谱仪在室内环境下对不同含水率的土壤样... 应用高光谱技术阐释土壤含水率光谱规律及对土壤含水率进行定量分析,为精准农业地表土壤水分的快速测定提供参考。该文以吉林省黑土土类中的黑土亚类土壤为研究对象,利用ASD FieldSpec FR便携式光谱仪在室内环境下对不同含水率的土壤样本进行光谱反射率测量和特征分析;通过对土壤样品高光谱反射率进行对数、倒数、一阶微分以及反射率倒数的一阶微分、反射率对数的一阶微分变换,运用统计分析中的相关系数计算进行了光谱反射率与土壤水分的相关分析,并提取了土壤光谱特征波段;采用逐步多元线性回归方法和指数模式分析法,进行了高光谱土壤含水率定量反演。研究结果表明,在低于田间持水率状况下,黑土土壤光谱反射率及其反射率一阶微分和反射率对数一阶微分变换的敏感波段主要集中在400~410、1400~1850和2050~2200nm范围内,其中2156nm处与土壤水分相关系数最高,达0.89;在波长1328、1439、1742和2156nm处,采用反射率对数一阶微分所建立的黑土土壤含水率预测方程的预测精度最好,决定系数为0.931。黑土土壤含水率高光谱反演模型的建立为土壤水分的快速测定提供了新的途径。 展开更多
关键词 土壤 含水率 模型 高光谱 光谱反射特性 光谱预测模型
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基于高光谱荧光技术的叶菜农药残留快速检测 被引量:29
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作者 陈菁菁 彭彦昆 +3 位作者 李永玉 王伟 吴建虎 单佳佳 《农业工程学报》 EI CAS CSCD 北大核心 2010年第S2期1-5,2,共6页
为了解决现有农药残留检测手段费时、复杂、前处理过程繁琐等不足,结合高光谱成像技术和荧光激发技术,搭建了高光谱荧光成像农药残留检测系统。在400~1100nm范围内获取叶菜表面毒死蜱的高光谱荧光图像,使用ENVI4.3软件提取了农药的荧... 为了解决现有农药残留检测手段费时、复杂、前处理过程繁琐等不足,结合高光谱成像技术和荧光激发技术,搭建了高光谱荧光成像农药残留检测系统。在400~1100nm范围内获取叶菜表面毒死蜱的高光谱荧光图像,使用ENVI4.3软件提取了农药的荧光光谱信息。研究结果表明,毒死蜱在甲醇溶液中具有较强的荧光特性,在437nm附近产生荧光发射光谱,并且不同浓度的毒死蜱农药具有不同的荧光发射光谱峰值,随着农药浓度的降低其荧光特征峰值也降低。研究结果可为进一步开发和研究快速、精确的农药残留检测仪器提供理论依据。 展开更多
关键词 检测器 农药 蔬菜 高光谱成像 荧光
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基于高光谱遥感的小麦叶片氮积累量 被引量:42
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作者 冯伟 朱艳 +3 位作者 田永超 曹卫星 姚霞 李映雪 《生态学报》 CAS CSCD 北大核心 2008年第1期23-32,共10页
作物氮素状况是评价长势、提高产量和改善品质的重要指标,因此叶片氮积累量的实时无损估测对作物生产的氮素管理具有重要意义。以多个小麦品种在不同施氮水平下的连续3 a大田试验为基础,研究了小麦叶片氮积累量与冠层高光谱参数的定量... 作物氮素状况是评价长势、提高产量和改善品质的重要指标,因此叶片氮积累量的实时无损估测对作物生产的氮素管理具有重要意义。以多个小麦品种在不同施氮水平下的连续3 a大田试验为基础,研究了小麦叶片氮积累量与冠层高光谱参数的定量关系。结果表明,冠层叶片氮积累量随着施氮水平的提高而增加,光谱反射率在不同叶片氮积累量水平下发生相应的变化。叶片氮积累量的敏感波段主要存在于近红外平台和可见光区,其中,"红边"区域表现最为显著。通过微分等技术构造多种植被指数,对高光谱参数和叶片氮积累量间进行相关回归分析,SD r/SDb、FD742和AVHRR-GVI 3个参数与叶片氮积累量关系最密切,方程拟合决定系数R2分别为0.9163、0.9097和0.9142,估计标准误差SE分别为1.165、1.079和1.077。经不同年际独立数据的检验表明,利用光谱参数FD742建立的模型对叶片氮积累量的估测精度为0.8449,预测的RMSE为0.984;红边位置REPIG对叶片氮积累量的估测精度和预测的RMSE分别为0.8394和1.014,表明预测值与观察值之间符合精度高,比较而言,FD742为自变量建立的模型可以更好地评估不同条件下叶片氮素积累状况。 展开更多
关键词 小麦 高光谱遥感 叶片氮积累量 监测模型
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生物多样性近地面遥感监测:应用现状与前景展望 被引量:33
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作者 郭庆华 刘瑾 +7 位作者 李玉美 翟秋萍 王永财 吴芳芳 胡天宇 万华伟 刘慧明 申文明 《生物多样性》 CAS CSCD 北大核心 2016年第11期1249-1266,共18页
近年来中国生物多样性监测与研究网络(Sino BON)建设得到了快速发展,为我国生物多样性长期监测和研究提供了良好的平台条件。其中,以激光雷达技术为核心的近地面遥感平台,作为Sino BON综合监测与管理中心的重要组成部分,已研发形成了较... 近年来中国生物多样性监测与研究网络(Sino BON)建设得到了快速发展,为我国生物多样性长期监测和研究提供了良好的平台条件。其中,以激光雷达技术为核心的近地面遥感平台,作为Sino BON综合监测与管理中心的重要组成部分,已研发形成了较为成熟的软、硬件技术体系,可以提供林下地形建模,林分高度、林分表面结构,林窗或内部分界线,郁闭度动态,植被群落划分、群落内部精细空间结构,单木高度与胸径,冠层形态、周长和盖度,物种识别,亚米级三维景观图等数字产品,从而能够为国家相关部门和研究单位开展多种时空尺度的生物多样性监测、评价和保护工作提供精准、高效的技术支持。本文首先介绍了遥感技术在生物多样性研究中的应用发展历史及最新趋势。然后在生物多样性遥感监测直接和间接两种方法研究进展基础之上,总结了从遥感数据中可提取的重要生物多样性指标,以及选择不同类型遥感数据源时需要考虑的时空尺度信息。在详细阐述NEON、CEOS、GEO BON等国际合作组织推动遥感技术开展生物多样性监测的过程中指明:以无人机为代表的近地面遥感平台具有机动灵活、高效低廉和高分辨率的特点,可在卫星平台、载人航空平台和地面常规调查平台之间架构起生物多样性信息尺度推绎不可或缺的中间桥梁,将是未来生物多样性监测的一个重要手段。最后,文章指出:Sino BON近地面遥感平台的逐步建设完善将为我国生物多样性监测提供全方位的立体定量化信息,在促进我国生物多样性监测网络向跨尺度等级动态系统监测、多源信息集成、智能决策与服务的平台方向发展意义重大。 展开更多
关键词 激光雷达 高光谱遥感 定量三维生境 监测指标 生物多样性制图
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淹水胁迫下棉花叶片高光谱特征及叶绿素含量估算模型 被引量:24
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作者 徐道青 刘小玲 +4 位作者 王维 陈敏 阚画春 李常凤 郑曙峰 《应用生态学报》 CAS CSCD 北大核心 2017年第10期3289-3296,共8页
为即时监测淹水胁迫下棉花功能叶叶绿素含量,确立叶绿素含量与单叶光谱特征参数的定量关系,本文以遮雨棚内蕾期淹水胁迫下的盆栽棉花为研究对象,淹水后每3 d对棉花叶片进行测定、取样,综合分析叶绿素含量与高光谱特征参数的相关性,并构... 为即时监测淹水胁迫下棉花功能叶叶绿素含量,确立叶绿素含量与单叶光谱特征参数的定量关系,本文以遮雨棚内蕾期淹水胁迫下的盆栽棉花为研究对象,淹水后每3 d对棉花叶片进行测定、取样,综合分析叶绿素含量与高光谱特征参数的相关性,并构建和验证叶绿素含量的估算模型.结果表明:随着淹水胁迫程度的加重,叶片叶绿素含量下降;叶片原始光谱反射率、一阶微分光谱反射率分别在580、697 nm波段附近与叶绿素含量呈显著负相关;利用差值指数和归一化指数建立的估算模型优于单波段线性模型,其中以植被指数(DR_(697)-DR_(738))/(DR_(697)+DR_(738))为自变量建立的模型棉花单叶叶绿素含量估算值与实测值拟合度最好,拟合系数为0.814,可用于淹水胁迫下棉花单叶叶绿素含量的估测. 展开更多
关键词 棉花 高光谱特征 淹水胁迫 叶绿素含量 植被指数
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