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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
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
Rapid thermal sensors with high resolution based on an adaptive dual-comb system Special Feature on Precision Measurement and Inst
Yi-zheng GUO, Ming YAN, Qiang HAO, Kang-wen YANG, Xu-ling SHEN, He-ping ZENG
Frontiers of Information Technology & Electronic Engineering 2019, Volume 20, Issue 5, Pages 674-684 doi: 10.1631/FITEE.1800347
We report a high-resolution rapid thermal sensing based on adaptive dual comb spectroscopy interrogated with a phase-shifted fiber Bragg grating (PFBG). In comparison with traditional dual-comb systems, adaptive dual-comb spectroscopy is extremely simplified by removing the requirement of strict phase-locking feedback loops from the dual-comb configuration. Instead, two free-running fiber lasers are adopted as the light sources. Because of good compensation of fast instabilities with adaptive techniques, the optical response of the PFBG is precisely characterized through a fast Fourier transform of the interferograms in the time domain. Single-shot acquisition can be accomplished rapidly within tens of milliseconds at a spectral resolution of 0.1 pm, corresponding to a thermal measurement resolution of 0.01 °C. The optical spectral bandwidth of the measurement also exceeds 14 nm, which indicates a large dynamic temperature range. It shows great potential for thermal sensing in practical outdoor applications with a loose self-control scheme in the adaptive dual-comb system.
Keywords： Interferometers Fiber sensors Laser spectroscopy
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
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
Innovative Scanners Boost Medical Imaging Quality and Utility
Mitch Leslie
Engineering 2022, Volume 16, Issue 9, Pages 3-5 doi: 10.1016/j.eng.2022.07.005
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
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
Technology of Measurement and Control by Welding Arc Spectral Information and Its Application
Li Junyue,Yang Yunqiang,Li Huan,Zhang Xiaonan,Yang Lijun
Strategic Study of CAE 2001, Volume 3, Issue 7, Pages 21-29
Welding arc is full of spectral information. Studying and utilizing the information to diagnose and control the welding arc is the most effective way to develop and improve the welding technology. Furthermore, it can be used to study and control other relative physical phenomena (such as gaseous plasma, laser processing plasma, underwater plasma arc, etc.). It is of great theoretical and practical significance. This paper has summarized the developing situation of the research on this field, expounded the principle of measurement and control by welding arc spectral information, described the application situation of welding arc spectral information, for example, the arc diagnosis, monitoring of arc atmosphere, imaging of arc welding region and control of droplet transfer in pulsed MIG welding, etc. At the same time, the authors have also introduced the application of arc spectral information in the development of plasma technology, such as in the development of plasma torch with carbon electrode and in the judgement of local thermodynamic equilibrium of underwater plasma arc. At last the authors have put forward some points of basic view on the technology and pointed out its developing direction.
Keywords： spectral information welding arc plasma diagnosis automation
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
Research on Droplet Transfer Spectral Information in Pulsed MIG Welding
Li Junyue,Yang Lijun,Hu Shenggang,Li Huan,Liu Gang
Strategic Study of CAE 2000, Volume 2, Issue 7, Pages 79-86
By the aid of the spectrum detecting device of welding arc, the droplet transfer spectral information of pulsed MIG welding has been researched experimentally. Results show that the arc spectral information can reflect well droplet transfer process in pulsed MIG welding. Many kinds of spectral information modes of droplet transfer have been found, which can reflect various droplet transfer types, such as one-peak-zero-base, one-peak-one-base, one-peak-two-base, two-peak-zero-base, two-peak-one-base, two-peak-two-base, three-peak-zero-base and so on. Especially, they can sharply and clearly reflect multiple drops spray transfer in the period of pulse peak. These spectral information have excellent character and therefore the spectral real-time and precise control of droplet transfer in pulsed MIG welding will be realized.
Keywords： arc spectral information pulsed MIG welding droplet transfer transfer mode
Antenna design and analysis of Fengyun-3 microwave humidity sounder
Wang Hongjian,Li Jing,Liu Heguang,Zhang Shengwei
Strategic Study of CAE 2009, Volume 11, Issue 4, Pages 39-45
Fengyun-3(FY-3) microwave humidity sounder antenna has the following specialties: high gain, low noise, high beam efficiency and high frequency. This Antenna has great influence on the precision of the whole system of FY-3MHS (microwave humidity sounder), offset parabolic antennae with conical corrugated horns are selected for these antennae. The frequencies of the antenna are 150 GHz and 183 GHz respectively (up to the highest frequency of the payload for the domestic satellite ), in addition, dual linear polarizations are also needed for the 150 GHz channels. Great challenges are brought about with the stringent demand for the FY-3MHS antenna. The analysis and design of this antenna need intercross knowledge of the electromagnetic theory, mechanics, manufacturing, measurements, quasi-optics, thermal and orbit etc. The successful design and assembly of FY-3MHS antennae fill up the gap of remote sensing in our country and stride a greatly leap in antenna theory.
Keywords： FY-3MHS offset parabolic antenna corrugated horn remote sensing
Sun Li,Su Gengqiang,Liu Yanmei,Zhao Yanyan and Shi Gangrong
Strategic Study of CAE 2012, Volume 14, Issue 3, Pages 70-75
The present study was carried out to examine the effects of low and variable water conditions on plant biomass, root to shoot ratio, chlorophyll fluorescence, gas exchange and spectral features in leaves of maize (Zea mays cv. Suyu 19) by pot experiment. The results showed that continuing drought led to an inhibition of plant growth, increase of root to shoot ratio, and inhibition of photosynthesis through stomatal and/or nonstomatal limitations. The mSR705, chlNDI and REP were also significantly reduced by continuing drought compared to the controls, whereas SIPI was unaffected. Under the low and variable water conditions, plant growth was inhibited, however, the root to shoot ratio, chlorophyll fluorescence, gas exchange and spectral properties were similar to the controls. The results indicated that the maintenance of biomass allocation, photosynthesis and spectral reflectance might be an important mechanism for maize to adapt the low and variable water conditions.
Keywords： Maize low and variable water conditions chlorophyll fluorescence gas exchange spectral reflectance
Adaptive Wavelet Thresholding Denoising Used in Gravitational Signal Processing
Zhao Liye,Zhou Bailing,Li Kunyu
Strategic Study of CAE 2006, Volume 8, Issue 3, Pages 49-52
The theory of wavelet thresholding denoising is analyzed and applied to process the data measured by gravimeter in order to effectively alleviate the effect of different noise in high precise gravitational system. The signal to noise ration (SNR) is used as the index for evaluating the performance of the data processing methods. Theoretical analysis and emulation experiments indicate that wavelet thresholding denoising, adaptive wavelet thresholding denoising and adaptive Kalman filtering are all effective in alleviating the effects of different noise, but the performance of adaptive wavelet thresholding denoising is best.
Keywords： gravimeter signal processing wavelet transform adaptive wavelet threshold adaptive Kalman filering
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
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
Rapid thermal sensors with high resolution based on an adaptive dual-comb system
Yi-zheng GUO, Ming YAN, Qiang HAO, Kang-wen YANG, Xu-ling SHEN, He-ping ZENG
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
High-resolution spectral video acquisition
Lin-sen CHEN, Tao YUE, Xun CAO, Zhan MA, David J. BRADY
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
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
Technology of Measurement and Control by Welding Arc Spectral Information and Its Application
Li Junyue,Yang Yunqiang,Li Huan,Zhang Xiaonan,Yang Lijun
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
Research on Droplet Transfer Spectral Information in Pulsed MIG Welding
Li Junyue,Yang Lijun,Hu Shenggang,Li Huan,Liu Gang
Journal Article
Antenna design and analysis of Fengyun-3 microwave humidity sounder
Wang Hongjian,Li Jing,Liu Heguang,Zhang Shengwei
Journal Article
Properties of photosynthesis and spectral reflectance in leaves of maize under the low and variable water conditions
Sun Li,Su Gengqiang,Liu Yanmei,Zhao Yanyan and Shi Gangrong
Journal Article
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