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Review of compact computational spectral information acquisition systems Review Articles
Hongya Song, Wenyi Zhang, Haifeng Li, Xu Liu, Xiang Hao,haox@zju.edu.cn
Frontiers of Information Technology & Electronic Engineering 2020, Volume 21, Issue 8, Pages 1119-1266 doi: 10.1631/FITEE.1900266
Keywords: 光谱成像;计算成像;光谱仪
Emerging theories and technologies on computationalimaging Review
Xue-mei HU, Jia-min WU, Jin-li SUO, Qiong-hai DAI
Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 9, Pages 1207-1221 doi: 10.1631/FITEE.1700211
Keywords: Computational imaging Multi-scale and multi-dimensional Super-resolution Femto-photography 3D reconstruction Hyperspectral imaging
Fengle Zhu, Zhenzhu Su, Alireza Sanaeifar, Anand Babu Perumal, Mostafa Gouda, Ruiqing Zhou, Xiaoli Li, Yong He
Engineering 2023, Volume 22, Issue 3, Pages 171-184 doi: 10.1016/j.eng.2022.10.006
Plant pathogens continuously impair agricultural yields and food security. Therefore, the dynamic characterization of early pathogen progression is crucial for disease monitoring and presymptomatic diagnosis. Hyperspectral imaging (HSI) has great potential for tracking the dynamics of initial infected sites for presymptomatic diagnosis; however, no related studies have extracted fingerprint spectral signatures (FSSs) that can capture diseased lesions on leaves during the early infection stage in vivo or investigated the detection mechanism of HSI relating to the host biochemical responses. The FSSs denote unique and representative spectral signatures that characterize a specific plant disease. In this study, the FSSs of spot blotch on barley leaves inoculated with Bipolaris sorokiniana were discovered to characterize symptom development for presymptomatic diagnosis based on time-series HSI data analysis. The early spectral and biochemical responses of barley leaves to spot blotch progression were also investigated. The fullspectrum FSSs were physically interpretable and could capture the unique characteristics of chlorotic and necrotic tissues along with lesion progression, enabling the in situ visualization of the spatiotemporal dynamics of early plant–pathogen interactions at the pixel level. Presymptomatic diagnosis of spot blotch was achieved 24 h after inoculation—12 h earlier than the traditional polymerase chain reaction (PCR) assay or biochemical measurements. To uncover the mechanism of HSI presymptomatic diagnosis, quantitative relationships between the mean spectral responses of leaves and their biochemical indicators (chlorophylls, carotenoids, malondialdehyde (MDA), ascorbic acid (AsA), and reduced glutathione (GSH)) were developed, achieving determination coefficient of prediction set (Rp2) > 0.84 for regression models. The overall results demonstrated that, based on the association between HSI and in vivo planttrait alterations, the extracted FSSs successfully tracked the spatiotemporal dynamics of bipolaris spot blotch progression for presymptomatic diagnosis. Tests of this methodology on other plant diseases demonstrated its remarkable generalization potential for the early control of plant diseases.
Keywords: Hyperspectral imaging Fingerprint spectral signatures Spot blotch Leaf lesion progression Presymptomatic diagnosis Biochemical indicators
Fu Yunfei,Liu Qi,Wang Yu,Sun Liang,Li Rui,Ma Ming,Liu Guosheng
Strategic Study of CAE 2012, Volume 14, Issue 10, Pages 43-50
The method of satellite infrared and passive microwave remote sensing for precipitation were briefly introduced firstly. The instruments onboard the tropical rainfall measurement mission (TRMM) satellite and the application of their measurements were discussed . As for example, precipitation structure, relationship among altitude of cloud top and rain top with surface rain rate for a summer hot convective precipitation system were brought forth together with analyzing of long time dataset of the TRMM precipitation radar on precipitation climatology in Asia.At last, the prospect of the satellite active and passive remote sensing of precipitation in the near future were given.
Keywords: TRMM precipitation radar microwave imager spectrum precipitation
Phase problems in optical imaging Review
Guo-hai SITU, Hai-chao WANG
Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 9, Pages 1277-1287 doi: 10.1631/FITEE.1700298
Keywords: Phase retrieval Phase imaging Computational imaging Gerchberg-Saxton algorithm Optical encryption Computer-generated hologram
Analysis and research on extending lifespan technology of FY-3 microwave radiation imager
Liu Gaofeng,Chen Weiying,Weng Yihang,Yu Shuang and Wang Hua
Strategic Study of CAE 2013, Volume 15, Issue 7, Pages 101-105
Considering the characteristics of Fengyun-3(FY-3) satellite lifespan on orbit increased from 3 years to 5 years, the risk of extending lifespan was analyzed, and the reliability of scan driver system and receiver system which were critical items of microwave radiation imager was evaluated, taking corresponding measures from design and improving crafts reliability. Microwave radiation imager operates normally on orbit and provides effective reliability assurance according to these methods. Finally, the ideal of accelerated lifespan test was put forward at last.
Keywords: microwave radiation imager scan driver receiver lifespan reliability
Principles and applications of high-speed single-pixelimaging technology Review
Qiang GUO, Yu-xi WANG, Hong-wei CHEN, Ming-hua CHEN, Si-gang YANG, Shi-zhong XIE
Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 9, Pages 1261-1267 doi: 10.1631/FITEE.1601719
Keywords: Compressive sampling Single-pixel imaging Photonic time stretch Imaging flow cytometry
High-resolution spectral video acquisition Review
Lin-sen CHEN, Tao YUE, Xun CAO, Zhan MA, David J. BRADY
Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 9, Pages 1250-1260 doi: 10.1631/FITEE.1700098
Keywords: Multispectral/hyperspectral video acquisition Snapshot Under-sampling and reconstruction
Light field imaging for computer vision: a survey Review Article
Chen JIA, Fan SHI, Meng ZHAO, Shengyong CHEN
Frontiers of Information Technology & Electronic Engineering 2022, Volume 23, Issue 7, Pages 1077-1097 doi: 10.1631/FITEE.2100180
Keywords: Light field imaging Camera array Microlens array Epipolar plane image Computer vision
Cheng Liu, Chengzhi Xing, Qihou Hu, Qihua Li, Haoran Liu, Qianqian Hong, Wei Tan, Xiangguang Ji, Hua Lin, Chuan Lu, Jinan Lin, Hanyang Liu, Shaocong Wei, Jian Chen, Kunpeng Yang, Shuntian Wang, Ting Liu, Yujia Chen
Engineering 2022, Volume 19, Issue 12, Pages 71-83 doi: 10.1016/j.eng.2021.02.019
With the coming of the “14th Five-Year Plan”, the coordinated control of particulate matter with an aerodynamic diameter no greater than 2.5 μm (PM2.5) and O3 has become a major issue of air pollution prevention and control in China. The stereoscopic monitoring of regional PM2.5 and O3 and their precursors is crucial to achieve coordinated control. However, current monitoring networks are currently inadequate for monitoring the vertical profiles of both PM2.5 and O3 simultaneously and support air quality control. The University of Science and Technology of China (USTC) has established a nationwide ground-based hyperspectral stereoscopic remote sensing network based on multi-axis differential optical absorption spectroscopy (MAX-DOAS) since 2015. This monitoring network provides a significant opportunity for the regional coordinated control of PM2.5 and O3 in China. One-year vertical profiles of aerosol, NO2 and HCHO monitored from four MAX-DOAS stations installed in four megacities (Beijing, Shanghai, Shenzhen, and Chongqing) were used to characterize their vertical distribution differences in four key regions, Jing–Jin–Ji (JJJ), Yangtze River Delta (YRD), Pearl River Delta (PRD), and Sichuan Basin (SB), respectively. The normalized and yearly averaged aerosol vertical profiles below 400 m in JJJ and PRD exhibit a box shape and a Gaussian shape, respectively, and both show exponential shapes in YRD and SB. The NO2 vertical profiles in four regions all exhibit exponential shapes because of vehicle emissions. The shape of the HCHO vertical profile in JJJ and PRD was Gaussian, whereas an exponential shape was shown in YRD and SB. Moreover, a regional transport event occurred at an altitude of 600–1000 m was monitored in the southwest–northeast pathway of the North China Plain (NCP) by five MAX-DOAS stations (Shijiazhuang (SJZ), Wangdu (WD), Nancheng (NC), Chinese Academy of Meteorological Sciences (CAMS), and University of Chinese Academy of Sciences (UCAS)) belonging to the above network. The aerosol optical depths (AOD) in these five stations decreased in the order of SJZ > WD > NC > CAMS > UCAS. The short-distance regional transport of NO2 in the 700–900 m layer was monitored between WD and NC. As an important precursor of secondary aerosol, the peak of NO2 air mass in WD and NC all occurred 1 h earlier than that of aerosol. This was also observed for the short-distance regional transport of HCHO in the 700–900 m layer between NC and CAMS, which potentially affected the O3 concentration in Beijing. Finally, CAMS was selected as a typical site to determine the O3–NOx–volatile organic compounds (VOCs) sensitivities in vertical space. We found the production of O3 changed from predominantly VOCs-limited conditions to mainly mixed VOCs–NOx-limited condition from the 0–100 m layer to the 200–300 m layer. In addition, the downward transport of O3 could contribute to the increase of ground surface O3 concentration. This ground-based hyperspectral stereoscopic remote sensing network provide a promising strategy to support management of PM2.5 and O3 and their precursors and conduct attribution of sources.
Keywords: MAX-DOAS Stereoscopic monitoring Regional transport Ozone production Control strategy
Light field imaging: models, calibrations, reconstructions,and applications Review
Hao ZHU, Qing WANG, Jingyi YU
Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 9, Pages 1236-1249 doi: 10.1631/FITEE.1601727
Keywords: Light field imaging Plenoptic function Imaging model Calibration Reconstruction
Evaluation of a typical plateau deep lake by DOM spectral characteristics
Tian Linfeng,Hu Jiwei,Li Cunxiong,Huang Xianfei,Xie Weifang
Strategic Study of CAE 2010, Volume 12, Issue 6, Pages 80-84
Dissolved organic matter (DOM) is a focus and challenge in the field of water environmental research since it plays an important role in the restoration research of aquatic system. Ultraviolet-visible (UVVIS) spectroscopy and fluorescence spectrophotometer are often used as an effective way for extracting DOM characteristics. In the present research, spectral characteristics of DOM were studied in water samples from different locations of the Hongfeng Lake, a man-made deep karstic lake and a key drinking-water source for Guiyang City, Guizhou Province, and various components of organic matter distributed at different samples were identified. The UV-VIS absorption ratio values (E3/E4) for the water samples collected from the Hongfeng Lake ranged from 1.70 to 8.77,and in general these values at 10 m depth were higher than those at 5 m depth except site HWHDC, while the fluorescence ratio values (f450/f500) ranged from 1.38 to 1.52. It could thus be inferred that the main organic pollution was from terrestrial origin at present. It is found, however, that spectral characteristics of the water samples from sites HWHDC, BHHX and ZG are different from those from the other sites. In addition, the results indicated that the depth of water had correlation with the humification degree of organic matter.
Keywords: dissolved organic matter ultraviolet-visible spectral characteristics fluorescence spectroscopy correlations
Current Situation and Trend of the Phosphors for Full Spectrum LED Lighting
Chen Xiaoxia, Zhang Xia, Liu Ronghui, Liu Yuanhong, Zhou Yipeng, Zhuang Weidong
Strategic Study of CAE 2020, Volume 22, Issue 2, Pages 71-78 doi: 10.15302/J-SSCAE-2020.02.011
With the increase of the requirements for lighting quality, full spectrum light emitting diode (LED) lighting becomes the development hotspot. In this paper, the key materials for full spectrum LED phosphors are discussed and compared in detail. The advantages and disadvantages, research progress, and practical application of various color phosphors excited by violet and near ultraviolet light are emphasized, and then the existing problems, development trend, and industrial direction in this field are analyzed and prospected. Currently, there remain many problems in the phosphors excited by violet and near ultraviolet light, which can be applied in full spectrum. For example, the blue and cyan phosphors take on narrow emission spectrum, low light efficiency, and poor thermal stability; yellow phosphors and far-red phosphors have a low luminous efficiency due to their low absorption of violet or near ultraviolet light; and single matrix white phosphors have insufficient red light emission. Among them, luminous efficiency and thermal stability are the key factors restricting the application of the phosphors. Therefore, it is urgent to research the preparation and application technology of wide spectrum blue, cyan, yellow green, yellow, far-red, and single matrix white phosphors with high light efficiency and thermal stability, and develop the high-efficient and continuous preparation technology of the present phosphor products, to promote the further development of full spectrum LED.
Keywords: full spectrum LED high-quality lighting violet LED chip phosphors
Extended Hemispherical Lens and Its Applications in Millimeter Wave Focal Imaging Systems
Sun Zhongliang,Dou Wenbin
Strategic Study of CAE 2000, Volume 2, Issue 3, Pages 42-47
Recently millimeter wave imaging absorbs many attentions. Especially much research work has been done on the millimeter focal imaging because of its advantage of real time imaging. This paper analyzes extended hemispherical lens, which can be used in focal imaging. An integrated antenna array is placed at the back plane of the lens to receive the power focused by the lens. This structure can eliminate the effect of the surface wave exited in the thick dielectric substrates at millimeter wave wavelengths. Low loss and compact are its merit. Assuming an electromagnetic wave is incident on the lens surface, the field distribution in focal space of the lens is analyzed by using Stratton-Chu formula and ray tracing method. It will provide much information about the imaging performance of the lens. Experiments have been carried out for two types of incident waves, one is normally incident plane wave and another is Gaussian-beam. Good agreement has been found between experiments and calculation results. The lens antenna also can be used to eliminate the transition between paraboloidal antenna and integrated front-end in conventional integrated millimeter wave systems so that the system loss can be decreased and performance can be improved. Furthermore, the lens can be used to couple with a quasi-optical system. The results presented here will provide useful guidelines for the above mentioned applications.
Keywords: millimeter waves antennas imaging extended hemispherical lens
Quantitative Investigation of Tomographic Effects in Abnormal Regions of Complex Structures Article
Longjun Dong, Xiaojie Tong, Ju Ma
Engineering 2021, Volume 7, Issue 7, Pages 1011-1022 doi: 10.1016/j.eng.2020.06.021
The detection of abnormal regions in complex structures is one of the most challenging targets for underground space engineering. Natural or artificial geologic variations reduce the effectiveness of conventional exploration methods. With the emergence of real-time monitoring, seismic wave velocity tomography allows the detection and imaging of abnormal regions to be accurate, intuitive, and quantitative. Since tomographic results are affected by multiple factors in practical small-scale applications, it is necessary to quantitatively investigate those influences. We adopted an improved three-dimensional (3D) tomography method combining passive acoustic emission acquisition and active ultrasonic measurements. By varying individual parameters (i.e., prior model, sensor configuration, ray coverage, event distributions, and event location errors), 37 comparative tests were conducted. The quantitative impact of different factors was obtained. Synthetic experiments showed that the method could effectively adapt to complex structures. The optimal input parameters based on quantization results can significantly improve the detection reliability in abnormal regions.
Keywords: Detection of abnormal regions Tomographic effects Wave velocity Ray path
Title Author Date Type Operation
Review of compact computational spectral information acquisition systems
Hongya Song, Wenyi Zhang, Haifeng Li, Xu Liu, Xiang Hao,haox@zju.edu.cn
Journal Article
Emerging theories and technologies on computationalimaging
Xue-mei HU, Jia-min WU, Jin-li SUO, Qiong-hai DAI
Journal Article
Fingerprint Spectral Signatures Revealing the Spatiotemporal Dynamics of Bipolaris Spot Blotch Progression for Presymptomatic Diagnosis
Fengle Zhu, Zhenzhu Su, Alireza Sanaeifar, Anand Babu Perumal, Mostafa Gouda, Ruiqing Zhou, Xiaoli Li, Yong He
Journal Article
TRMM satellite onboard instruments and the application on precipitation analysis of their measurements
Fu Yunfei,Liu Qi,Wang Yu,Sun Liang,Li Rui,Ma Ming,Liu Guosheng
Journal Article
Analysis and research on extending lifespan technology of FY-3 microwave radiation imager
Liu Gaofeng,Chen Weiying,Weng Yihang,Yu Shuang and Wang Hua
Journal Article
Principles and applications of high-speed single-pixelimaging technology
Qiang GUO, Yu-xi WANG, Hong-wei CHEN, Ming-hua CHEN, Si-gang YANG, Shi-zhong XIE
Journal Article
High-resolution spectral video acquisition
Lin-sen CHEN, Tao YUE, Xun CAO, Zhan MA, David J. BRADY
Journal Article
Light field imaging for computer vision: a survey
Chen JIA, Fan SHI, Meng ZHAO, Shengyong CHEN
Journal Article
Ground-based Hyperspectral Stereoscopic Remote Sensing Network: A Promising Strategy to Learn Coordinated Control of O3 and PM2.5 over China
Cheng Liu, Chengzhi Xing, Qihou Hu, Qihua Li, Haoran Liu, Qianqian Hong, Wei Tan, Xiangguang Ji, Hua Lin, Chuan Lu, Jinan Lin, Hanyang Liu, Shaocong Wei, Jian Chen, Kunpeng Yang, Shuntian Wang, Ting Liu, Yujia Chen
Journal Article
Light field imaging: models, calibrations, reconstructions,and applications
Hao ZHU, Qing WANG, Jingyi YU
Journal Article
Evaluation of a typical plateau deep lake by DOM spectral characteristics
Tian Linfeng,Hu Jiwei,Li Cunxiong,Huang Xianfei,Xie Weifang
Journal Article
Current Situation and Trend of the Phosphors for Full Spectrum LED Lighting
Chen Xiaoxia, Zhang Xia, Liu Ronghui, Liu Yuanhong, Zhou Yipeng, Zhuang Weidong
Journal Article
Extended Hemispherical Lens and Its Applications in Millimeter Wave Focal Imaging Systems
Sun Zhongliang,Dou Wenbin
Journal Article