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Cu(Inx 1

Ga1–x)Se2 1

区域传输 1

叶斑病 1

叶片病斑进展 1

多光谱/高光谱视频采集；单次曝光；采样与重建 1

多轴差分吸收光谱仪 1

指纹光谱特征 1

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显症前诊断 1

激光烧蚀短程热效应 1

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由P1引起的功率损耗 1

电池到模块的效率差距 1

立体监测 1

臭氧生成 1

计算成像；多维多尺度；超分辨；飞秒成像；3D重建；超光谱成像 1

高光谱光致发光 1

高光谱成像 1

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Feature extraction of hyperspectral images for detecting immature green citrus fruit

Yongjun DING, Won Suk LEE, Minzan LI

《农业科学与工程前沿（英文）》 2018年第5卷第4期页码 475-484 doi: 10.15302/J-FASE-2018241

摘要：

At an early immature growth stage of citrus, a hyperspectral camera of 369–1042 nm was employed to acquire 30 hyperspectral images in order to detect immature green fruit within citrus trees under natural illumination conditions. First, successive projections algorithm (SPA) were implemented to select 677, 804, 563, 962, and 405 nm wavebands and to construct multispectral images from the original hyperspectral images for further processing. Then, histogram threshold segmentation using NDVI of 804 and 677 nm was implemented to remove image backgrounds. Three slope parameters, calculated from the pairs 405 and 563 nm, 563 and 677 nm, and 804 and 962 nm were used to construct a classifier to identify the potential citrus fruit. Then, a marker-controlled watershed segmentation based on wavelet transform was applied to obtain potential fruit areas. Finally, a green fruit detection model was constructed according to Grey Level Co-occurrence Matrix (GLCM) texture features of the independent areas. Three supervised classifiers, logistic regression, random forest and support vector machine (SVM) were developed using texture features. The detection accuracies were 79%, 75%, and 86% for the logistic regression, random forest, and SVM models, respectively. The developed algorithm showed a great potential for identifying immature green citrus for an early yield estimation.

关键词： hyperspectral green citrus image processing fruit detection precision agriculture yield mapping

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Detection of Huanglongbing (citrus greening) based on hyperspectral image analysis and PCR

Kejian WANG, Dongmei GUO, Yao ZHANG, Lie DENG, Rangjin XIE, Qiang LV, Shilai YI, Yongqiang ZHENG, Yanyan MA, Shaolan HE

《农业科学与工程前沿（英文）》 2019年第6卷第2期页码 172-180 doi: 10.15302/J-FASE-2019256

摘要：

Huanglongbing (HLB, citrus greening) is one of the most serious quarantine diseases of citrus worldwide. To monitor in real-time, recognize diseased trees, and efficiently prevent and control HLB disease in citrus, it is necessary to develop a rapid diagnostic method to detect HLB infected plants without symptoms. This study used Newhall navel orange plants as the research subject, and collected normal color leaf samples and chlorotic leaf samples from a healthy orchard and an HLB-infected orchard, respectively. First, hyperspectral data of the upper and lower leaf surfaces were obtained, and then the polymerase chain reaction (PCR) was used to detect the HLB bacterium in each leaf. The PCR test results showed that all samples from the healthy orchard were negative, and a portion of the samples from the infected orchard were positive. According to these results, the leaf samples from the orchards were divided into disease-free leaves and HLB-positive leaves, and the least squares support vector machine recognition model was established based on the leaf hyperspectral reflectance. The effect on the model of the spectra obtained from the upper and lower leaf surfaces was investigated and different pretreatment methods were compared and analyzed. It was observed that the HLB recognition rate values of the calibration and validation sets based on upper leaf surface spectra under 9-point smoothing pretreatment were 100% and 92.5%, respectively. The recognition rate values based on lower leaf surface spectra under the second-order derivative pretreatment were also 100% and 92.5%, respectively. Both upper and lower leaf surface spectra were available for recognition of HLB-infected leaves, and the HLB PCR-positive leaves could be distinguished from the healthy by the hyperspectral modeling analysis. The results of this study show that early and nondestructive detection of HLB-infected leaves without symptoms is possible, which provides a basis for the hyperspectral diagnosis of citrus with HLB.

关键词： citrus HLB hyperspectral identification PCR

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Non-negativematrix factorization based unmixing for principal component transformed hyperspectral data

Xiu-rui GENG,Lu-yan JI,Kang SUN

《信息与电子工程前沿（英文）》 2016年第17卷第5期页码 403-412 doi: 10.1631/FITEE.1600028

摘要： Non-negative matrix factorization (NMF) has been widely used in mixture analysis for hyperspectral remote sensing. When used for spectral unmixing analysis, however, it has two main shortcomings: (1) since the dimensionality of hyperspectral data is usually very large, NMF tends to suffer from large computational complexity for the popular multiplicative iteration rule; (2) NMF is sensitive to noise (outliers), and thus the corrupted data will make the results of NMF meaningless. Although principal component analysis (PCA) can be used to mitigate these two problems, the transformed data will contain negative numbers, hindering the direct use of the multiplicative iteration rule of NMF. In this paper, we analyze the impact of PCA on NMF, and find that multiplicative NMF can also be applicable to data after principal component transformation. Based on this conclusion, we present a method to perform NMF in the principal component space, named ‘principal component NMF’ (PCNMF). Experimental results show that PCNMF is both accurate and time-saving.

关键词： Non-negative matrix factorization (NMF) Principal component analysis (PCA) Endmember Hyperspectral

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Spectral characteristics of plant communities from salt marshes: A case study from Chongming Dongtan, Yangtze estuary, China

ZHANG Liquan, GAO Zhanguo, Armitage Richard, Kent Martin

《环境科学与工程前沿（英文）》 2008年第2卷第2期页码 187-197 doi: 10.1007/s11783-008-0004-1

摘要： The spectral reflectance of recently formed salt marshes at the mouth of the Yangtze River, which are undergoing invasion by , were assessed to determine the potential utility of remotely sensed data in assessing future invasion and changes in species composition. Following a review of published research on remote sensing of salt marshes, 53 locations along three transects were sampled for paired data on plant species composition and spectral reflectance using a FieldSpec Pro JR Field Portable Spectroradiometer. Spectral data were processed concerning reflectance, and the averaged reflectance values for each sample were re-analysed to correspond to a 12-waveband bandset of the Compact Airborne Spectral Imager. The spectral data were summarised using principal components analysis (PCA) and the relationships between the vegetation composition, and the PCA axes of spectral data were examined. The first PCA axis of the reflectance data showed a strong correlation with variability in near infrared reflectance and ‘brightness’, while the second axis was correlated with visible reflectance and ‘greenness’. Total vegetation cover, vegetation height, and mudflat cover were all significantly related to the first axis. The implications of this in terms of the ability of remote sensing to distinguish the various salt marsh species and in particular the invasive species were discussed. Major differences in species with various physiognomies could be recognised but problems occurred in separating early colonising from other species at that stage. Further work using multi-seasonal hyperspectral data might assist in solving these problems.

关键词： Spectral multi-seasonal hyperspectral invasive JR re-analysed

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高分辨率光谱视频采集 Review

Lin-sen CHEN, Tao YUE, Xun CAO, Zhan MA, David J. BRADY

《信息与电子工程前沿（英文）》 2017年第18卷第9期页码 1250-1260 doi: 10.1631/FITEE.1700098

摘要：与传统视频采集技术相比，高分辨率光谱视频采集技术能够为精细农业、环境监测、遥感、军事刑侦等诸多重要领域提供高维度、高精度场景特征信息。传统光谱仪主要采用的扫描系统无法满足动态场景下的采集需求，从而限制了光谱成像技术的应用范围。近来，得益于计算摄像理论和半导体技术的快速发展，光谱视频采集技术成为可能。本文首先详细介绍了传统光谱仪的基本理论与工作原理。其次，针对光谱视频采集的核心问题，从成像理论、系统结构、关键器件等方面回顾了近年出现的瞬拍式光谱采集技术。从进一步提升光谱视频采集精度的角度出发，通过主观质量评价与客观指标比较，分析和总结了各光谱成像系统的性能优势与弊端，同时讨论了计算摄像理论、半导体制备工艺对光谱视频采集技术发展的关键作用。

关键词：多光谱/高光谱视频采集；单次曝光；采样与重建

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用高光谱发光法研究Cu(In_x,Ga_1–x)Se₂ (CIGS)模块中由P1引起的功率损耗的成因 Article

César Omar Ramírez Quiroz, Laura-Isabelle Dion-Bertrand, Christoph J. Brabec, Joachim Müller, Kay Orgassa

《工程（英文）》 2020年第6卷第12期页码 1395-1402 doi: 10.1016/j.eng.2019.12.019

摘要：

在本文中，我们利用了高光谱高分辨率光致发光映射技术，这是一个强大的工具，可用于选择和优化在Cu(In_x,Ga_1-x)Se₂（CIGS）模块上对子电池进行图案化互连的激光烧蚀工艺。通过这种方式，我们可以完成对消融区域附近材料降解的深度监测以及对潜在机制的识别。具体而言，通过分析在CIGS沉积之前烧蚀的标准P1图案线，我们发现了沿着下部的钼槽边缘的异常发射猝灭效应。通过扫描电子显微镜（SEM）比较了P1边缘的横截面的形貌，我们进一步合理化产生这种效应的起因，但无法用厚度变化解释光发射的减少。我们还研究了激光诱导对CIGS沉积后的P1图案线带来的损伤。然后，我们首次记录了短距离损坏区域，该区域与在激光路径上应用的光学孔径无关。我们的发现能更好地理解P1引起的功率损耗，并为改进与行业相关的模块互连方案提供了新的见解。

关键词： Cu(Inx Ga1–x)Se2 电池到模块的效率差距由P1引起的功率损耗高光谱光致发光激光烧蚀短程热效应

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从中国首台紫外-可见光高光谱卫星仪器反演得到的高空间分辨率臭氧廓线 Article

Fei Zhao, Cheng Liu, Qihou Hu, Congzi Xia, Chengxin Zhang, Wenjing Su

《工程（英文）》 2024年第32卷第1期页码 107-116 doi: 10.1016/j.eng.2023.02.020

摘要：

Understanding the vertical distribution of ozone is crucial when assessing both its horizontal and vertical transport, as well as when analyzing the physical and chemical properties of the atmosphere. One of the most effective ways to obtain high spatial resolution ozone profiles is through satellite observations. The Environmental Trace Gases Monitoring Instrument (EMI) deployed on the Gaofen-5 satellite is the first Chinese ultraviolet-visible hyperspectral spectrometer. However, retrieving ozone profiles using backscattered radiance values measured by the EMI is challenging due to unavailable measurement errors and a low signal-to-noise ratio. The algorithm developed for the Tropospheric Monitoring Instrument did not allow us to retrieve 87% of the EMI pixels. Therefore, we developed an algorithm specific to the characteristics of the EMI. The fitting residuals are smaller than 0.3% in most regions. The retrieved ozone profiles were in good agreement with ozonesonde data, with maximum mean biases of 20% at five latitude bands. By applying EMI averaging kernels to the ozonesonde profiles, the integrated stratospheric column ozone and tropospheric column ozone also showed excellent agreement with ozonesonde data. The lower layers (0–7.5 km) of the EMI ozone profiles reflected the seasonal variation in surface ozone derived from the China National Environmental Monitoring Center (CNEMC). However, the upper layers (9.7–16.7 km) of the ozone profiles show different trends, with the ozone peak occurring at an altitude of 9.7–16.7 km in March. A stratospheric intrusion event in central China from August 11 to 15, 2019, is captured using the EMI ozone profiles, potential vorticity data, and relative humidity data. The increase in the CNEMC ozone concentration showed that downward transport enhanced surface ozone pollution.

关键词： Ozone profiles EMI Soft calibration Floor noise correction Stratospheric ozone intrusion

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计算成像领域新理论和新方法 Review

Xue-mei HU, Jia-min WU, Jin-li SUO, Qiong-hai DAI

《信息与电子工程前沿（英文）》 2017年第18卷第9期页码 1207-1221 doi: 10.1631/FITEE.1700211

摘要：计算成像学从光传播和信息传递角度为光的整个成像过程建模，将计算能力引入传统光学成像，旨在突破视觉信息记录的局限。计算成像领域的进展，促进了不同基础学科和应用学科的发展。我们概述了计算成像领域的基本原则和方法、发展过程及其在科学发展中起到的重要作用，从视觉信号的不同维度——包括空间、时间、角度、光谱、相位——分别综述了计算成像领域最新和最先进的研究进展，并讨论了该领域有发展前景的研究方向。

关键词：计算成像；多维多尺度；超分辨；飞秒成像；3D重建；超光谱成像

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指纹光谱特征揭示叶斑病时空动态发展以实现显症前诊断 Article

朱逢乐, 苏珍珠, Alireza Sanaeifar, Anand Babu Perumal, Mostafa Gouda, 周瑞清, 李晓丽, 何勇

《工程（英文）》 2023年第22卷第3期页码 171-184 doi: 10.1016/j.eng.2022.10.006

摘要：

植物病原菌不断危害农业生产和粮食安全。因此，病害发展早期的动态表征对病变监测和显症前诊断至关重要。高光谱成像（HSI）在跟踪病害初始侵染部位的动态进程以进行显症前诊断方面具有巨大潜力。然而，目前尚无相关文献提取出早期感染阶段活体叶片病变组织的指纹光谱特征（FSS），也没有探究HSI的检测机制。FSS是指能够表征特定植物病害的独特、有代表性的光谱特征。在本研究中，基于时序HSI数据分析，提取了接种麦根平脐蠕孢菌（Bipolaris sorokiniana）的大麦叶片的FSS，以表征叶斑病症状发展，实现显症前诊断。还研究了叶斑病早期发展阶段叶片的光谱和生化响应。本文所提取的全波段FSS能够捕捉病变发展过程中褪绿组织和坏死组织的独特特征，从而原位可视化植物-病原菌像素级的早期互作动态进程。进一步，实现了接种后24 h 叶斑病的显症前诊断，比传统的聚合酶链式反应（PCR）测定或生化测定提前了12 h。为了揭示HSI 显症前诊断的机制，还建立了叶片的平均光谱响应与其生化指标（叶绿素、类胡萝卜素、丙二醛、抗坏血酸和还原型谷胱甘肽）之间的定量关系，回归模型在预测集的决定系数（R_p²）均高于0.84。总体结果表明，HSI反映了活体植物特性的变化，所提取的FSS可成功跟踪叶斑病发生发展的时空动态进程，实现显症前诊断。在其他植物病害上的试验表明，该方法在植物病害早期控制方面具有较大的推广潜力。

关键词：高光谱成像指纹光谱特征叶斑病叶片病斑进展显症前诊断生化指标

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地基超光谱立体遥感网络——一种探究中国PM_2.5和O₃协同控制的新策略 Article

刘诚, 邢成志, 胡启后, 李启华, 刘浩然, 洪茜茜, 谈伟, 季祥光, 林华, 陆川, 林继楠, 刘瀚洋, 魏少聪, 陈健, 杨昆鹏, 王顺天, 柳婷, 陈羽佳

《工程（英文）》 2022年第19卷第12期页码 71-83 doi: 10.1016/j.eng.2021.02.019

摘要：

进入“十四五”时期，PM_2.5（空气动力学当量直径小于等于2.5 μm的颗粒物）和O₃的协同控制成为我国大气污染防治的重大课题。PM_2.5、O₃及其前体物的立体监测对于实现协同控制至关重要。然而，目前的监测网络不足以同时监测PM_2.5和O₃的垂直分布以及支持空气质量控制。2015 年以来，中国科学技术大学（USTC）基于多轴差分吸收光谱仪（MAX-DOAS）在全国范围内主导建立了地基超光谱遥感网络。该立体监测网络为我国PM_2.5和O₃的区域协同控制提供了重要机遇。基于搭设于四个特大城市（北京、上海、深圳和重庆）的四个MAX-DOAS 监测站获取的一年时间的气溶胶、NO₂和HCHO的垂直廓线，探究京津冀（JJJ）、长三角（YRD）、珠三角（PRD）和四川盆地（SB）四大典型污染区域的大气污染物垂直分布差异。400 m以下归一化和年平均的气溶胶垂直廓线在JJJ 和PRD地区分别呈箱型和高斯型分布，在YRD和SB地区都呈E指数型分布。由于四个区域的NO₂都主要来自交通车辆排放，因此NO₂在四个区域都呈E指数型分布。HCHO垂直廓线在JJJ 和PRD地区呈高斯型分布，在YRD和SB地区呈E指数型分布。此外，立体监测网络中的五个MAX-DOAS 站点[石家庄（SJZ）、望都（WD）、南城（NC）、中国气象科学研究院（CAMS）和中国科学院大学（UCAS）]同时监测到一次发生在华北平原（NCP）西南—东北通道海拔600~1000 m 的典型区域传输事件。气溶胶光学厚度（AOD）在上述五个站点表现为SJZ > WD > NC > CAMS > UCAS。在WD和NC之间监测到了发生在700~900 m高空的NO₂短距离区域传输。作为二次气溶胶的重要前体物，研究发现WD和NC的NO₂气团峰值均比其气溶胶消光气团峰值早出现约1 h。同时监测到了NC和CAMS之间发生在700~900 m高空的HCHO短距离区域传输，这可能会对北京的O₃浓度造成潜在影响。最后，选择CAMS作为典型站点探究垂直方向O₃-NO_x-挥发性有机化合物（VOC）的敏感性。研究发现O₃在0~100 m和100~200 m高度层分别受VOC控制和VOC-NO_x混合控制。此外，O₃的向下输送也可能会增加近地面O₃的浓度。该地基超光谱立体遥感网络为支持PM_2.5、O₃及其前体物的管控和溯源提供了一种非常具有前景的策略。