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Research in Astronomy and Astrophysics 2014年第12期14卷 1567-1577页

作者： Zhi-Ping He Bin-Yong Wang Gang Lü chun-lai li li-Yin Yuan Rui Xu Bin liu Kai Chen Jian-Yu Wang Key Laboratory of Space Active Opto-Electronics Technology Shanghai Institute of Technical Physics Chinese Academy of Sciences The Science and Application Center for Moon and Deep Space Exploration National Astronomical Observatories Chinese Academy of Sciences

The Visible and Near-Infrared Imaging Spectrometer （VNIS）, using two acousto-optic tunable filters as dispersive components, consists of a VIS/NIR imag- ing spectrometer （0.45-0.95 μm）, a shortwave IR spectrometer （0.9-2.4 p.m） and a calibration unit with dust-proofing functionality. The VNIS was utilized to detect the spectrum of the lunar surface and achieve in-orbit calibration, which satisfied the re- quirements for scientific detection. Mounted at the front of the Yutu rover, lunar ob- jects that are detected with the VNIS with a 45° visual angle to obtain spectra and ge- ometrical data in order to analyze the mineral composition of the lunar surface. After landing successfully on the Moon, the VNIS performed several explorations and cal- ibrations, and obtained several spectral images and spectral reflectance curves of the lunar soil in the region of Mare Imbrium. This paper describes the working principle and detection characteristics of the VNIS and provides a reference for data processing and scientific applications.

关键词： space vehicles: instruments -- instrumentation: spectrographs -- Moon-- techniques: spectroscopic

Ground experiments and performance evaluation of the Low-Frequency Radio Spectrometer onboard the lander of Chang’e-4 mission

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Research in Astronomy and Astrophysics 2021年第5期21卷 139-146页

作者： Xin-Ying Zhu Yan Su Yi-Cai Ji Hong-Bo Zhang Bo Zhao Jun-duo li Shun Dai Xi-Ping Xue chun-lai li Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Institute of Electronics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The Low-Frequency Radio Spectrometer(LFRS)is a scientific payload onboard the Chang’e-4 lunar lander launched in December *** LFRS provides in-situ measurements of the low-frequency radio phenomena on the far-side of theMoon for the first time in human *** evaluate the performance of the LFRS,a series of ground experiments are conducted using an engineering model of the *** is not easy to perform the experiments because the Electro Magnetic Interference(EMI)from the Chang’e-4 lunar lander itself and the environment is very *** results after EMI mitigation show that the sensitivity of the LFRS may be 10^(−18)W m^(−2)Hz^(−1).

关键词： Moon:far-side space vehicles:instruments techniques:spectroscopic

Analysis on unit maximum capacity of orthogonal multiple watermarking for multimedia signals in B5G wireless communications

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Digital Communications and Networks 2024年第1期10卷 38-44页

作者： Mianjie li Senfeng lai Jiao Wang Zhihong Tian Nadra Guizani Xiaojiang Du chun Shan School of Electronics and Information Guangdong Polytechnic Normal UniversityGuangzhou510665China Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou510006China Schoolof Electrical Engineering and Computer Science Washington State UniversityPullmanWA99164USA Department of Computer and Information Science Temple UniversityPhiladelphiaPA19122USA

Beyond-5G(B5G)aims to meet the growing demands of mobile traffic and expand the communication *** that intelligent applications to B5G wireless communications will involve security issues regarding user data and operational data,this paper analyzes the maximum capacity of the multi-watermarking method for multimedia signal hiding as a means of alleviating the information security problem of *** multiwatermarking process employs spread transform dither *** the watermarking procedure,Gram-Schmidt orthogonalization is used to obtain the multiple spreading ***,multiple watermarks can be simultaneously embedded into the same position of a multimedia ***,the multiple watermarks can be extracted without affecting one another during the extraction *** analyze the effect of the size of the spreading vector on the unit maximum capacity,and consequently derive the theoretical relationship between the size of the spreading vector and the unit maximum capacity.A number of experiments are conducted to determine the optimal parameter values for maximum robustness on the premise of high capacity and good imperceptibility.

关键词： B5G Multimedia information security Spread transform dither modulation Spreading vector measurement Unit maximum capacity

Study on the Influencing Factors of the Permittivity Estimation Method Considering Antenna Layout Based on Lunar Penetrating Radar

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Research in Astronomy and Astrophysics 2022年第10期22卷 11-23页

作者： Rui-Gang Wang Yan Su Zong-Yu Zhang Qing Zhang Chen-Di liu Tian-Sheng Hong Shu-Ning liu Wei Du Shun Dai chun-Yu Ding chun-lai li National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science Universty of Chinese Academy of SciencesBeijing 100049China The 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang 050081China Institute of Moon-base Exploration and Observation Institute of Advance StudyShenzhen UniversityShenzhen 518060China

The permittivity of lunar regolith is crucial for further processing and interpretation of radar *** conventional hyperbolic fitting method ignores the antenna height and spacing and has a significant error at a shallow *** the new method that considers the layout of the antenna,the influencing factors have not been *** this paper,we studied the influence of the position of the hyperbola peak and time zero on the new method for permittivity *** simulation results show that when the input errors of time zero,abscissa and ordinate of the hyperbolic peak are±2 ns,±0.02 m and±0.2 ns respectively,the average errors of the calculated results by points within 1 m from the hyperbolic peak are 10.0%,16.7%and 38.2%,*** improve the accuracy,we used the average results by points that are horizontally more than 1 m away from the hyperbola ***,we calculated the permittivity of the lunar regolith by the new method based on Lunar Penetrating Radar *** average permittivity of the lunar regolith is estimated to be 3.3±1.2.

关键词： Moon-techniques radar astronomy-techniques image processing

Data preprocessing and preliminary results of the Moon-based Ultraviolet Telescope on the CE-3 lander

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Research in Astronomy and Astrophysics 2014年第12期14卷 1674-1681页

作者： Wei-Bin Wen Fang Wang chun-lai li Jing Wang li Cao Jian-Jun liu Xu Tan Yuan Xiao Qiang Fu Yan Su Wei Zuo National Astronomical Observatory Chinese Academy of Sciences Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of Sciences

The Moon-based Ultraviolet Telescope （MUVT） is one of the payloads on the Chang＇e-3 （CE-3） lunar lander. Because of the advantages of having no at- mospheric disturbances and the slow rotation of the Moon, we can make long-term continuous observations of a series of important celestial objects in the near ultra- violet band （245-340 nm）, and perform a sky survey of selected areas, which can- not be completed on Earth. We can find characteristic changes in celestial brightness with time by analyzing image data from the MUVT, and deduce the radiation mech- anism and physical properties of these celestial objects after comparing with a phys- ical model. In order to explain the scientific purposes of MUVT, this article analyzes the preprocessing of MUVT image data and makes a preliminary evaluation of data quality. The results demonstrate that the methods used for data collection and prepro- cessing are effective, and the Level 2A and 2B image data satisfy the requirements of follow-up scientific researches.

关键词： Chang'e-3 mission -- the Moon-based Ultraviolet Telescope -- data preprocessing -- near ultraviolet band

A method and results of color calibration for the Chang'e-3 terrain camera and panoramic camera

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Research in Astronomy and Astrophysics 2014年第12期14卷 1557-1566页

作者： Xin Ren chun-lai li Jian-Jun liu Fen-Fei Wang Jian-Feng Yang En-Hai liu Bin Xue Ru-Jin Zhao Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Institute of Optics and Electronics Chinese Academy of Sciences

The terrain camera （TCAM） and panoramic camera （PCAM） are two of the major scientific payloads installed on the lander and rover of the Chang＇e 3 mission re- spectively. They both use a Bayer color filter array covering CMOS sensor to capture color images of the Moon＇s surface. RGB values of the original images are related to these two kinds of cameras. There is an obvious color difference compared with human visual perception. This paper follows standards published by the International Commission on Illumination to establish a color correction model, designs the ground calibration experiment and obtains the color correction coefficient. The image qual- ity has been significantly improved and there is no obvious color difference in the corrected images. Ground experimental results show that：（1） Compared with uncor- rected images, the average color difference of TCAM is 4.30, which has been reduced by 62.1%. （2） The average color differences of the left and right cameras in PCAM are 4.14 and 4.16, which have been reduced by 68.3% and 67.6% respectively.

关键词： Moon -- methods: data analysis -- techniques: image processing

Analysis of the geomorphology surrounding the Chang'e-3 landing site

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Research in Astronomy and Astrophysics 2014年第12期14卷 1514-1529页

作者： chun-lai li ling-li Mu Xiao-Duan Zou Jian-Jun liu Xin Ren Xing-Guo Zeng Yi-Man Yang Zhou-Bin Zhang Yu-Xuan liu Wei Zuo Han li Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences

Chang＇e-3 （CE-3） landed on the Mare Imbrium basin in the east part of Sinus Iridum （19.51°W, 44.12°N）, which was China＇s first soft landing on the Moon and it started collecting data on the lunar surface environment. To better understand the environment of this region, this paper utilizes the available high-resolution topography data, image data and geological data to carry out a detailed analysis and research on the area surrounding the landing site （Sinus Iridum and 45 km×70 km of the landing area） as well as on the topography, landform, geology and lunar dust of the area surrounding the landing site. A general topographic analysis of the surrounding area is based on a digital elevation model and digital elevation model data acquired by Chang＇e-2 that have high resolution; the geology analysis is based on lunar geological data published by USGS; the study on topographic factors and distribution of craters and rocks in the surrounding area covering 4km^4km or even smaller is based on images from the CE-3 landing camera and images from the topographic camera; an analysis is done of the effect of the CE-3 engine plume on the lunar surface by comparing images before and after the landing using data from the landing camera. A comprehensive analysis of the results shows that the landing site and its surrounding area are identified as typical lunar mare with flat topography. They are suitable for maneuvers by the rover, and are rich in geological phenomena and scientific targets, making it an ideal site for exploration.

关键词： atlases -- methods: data analysis -- techniques: image processing --techniques: photometric

Laboratory verification of the Active Particle-induced X-ray Spectrometer(APXS) on the Chang'e-3 mission

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Research in Astronomy and Astrophysics 2015年第11期15卷 1893-1904页

作者： Guang-liang Zhang chun-lai li Xiao-Hui Fu li-Yan Zhang Cao Ban Han li Yong-liao Zou Wen-Xi Peng Xing-Zhu Cui Cheng-Mo Zhang Huan-Yu Wang National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences Institute of High Energy Physics Chinese Academy of Sciences

In the Chang＇e-3 mission, the Active Particle-induced X-ray Spectrometer（APXS） on the Yutu rover is used to analyze the chemical composition of lunar soil and rock samples. APXS data are only valid are only if the sensor head gets close to the target and integration time lasts long enough. Therefore, working distance and integration time are the dominant factors that affect APXS results. This study confirms the ability of APXS to detect elements and investigates the effects of distance and time on the measurements. We make use of a backup APXS instrument to determine the chemical composition of both powder and bulk samples under the conditions of different working distances and integration times. The results indicate that APXS can detect seven major elements, including Mg, Al, Si, K, Ca, Ti and Fe under the condition that the working distance is less than 30 mm and having an integration time of 30 min. The statistical deviation is smaller than 15%. This demonstrates the instrument＇s ability to detect major elements in the sample. Our measurements also indicate the increase of integration time could reduce the measurement error of peak area, which is useful for detecting the elements Mg, Al and Si. However, an increase in working distance can result in larger errors in measurement, which significantly affects the detection of the element Mg.

关键词： deviation rock lunar instrument verification backup rover detecting basalt enough

Polyimide covalent organic frameworks as efficient solid-state li^(+) electrolytes

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Science China Chemistry 2024年第5期67卷 1647-1652页

作者： Xu liu Shi Wang Siqi liu Chengfang liu Xiangchun li Jian Wu Dazhi li Shihao Xu Chongyang liu Wen-Yong lai State Key Laboratory of Organic Electronics and Information Displays(SKLOEID) Institute of Advanced Materials(IAM)School of Chemistry and Life SciencesNanjing University of Posts&TelecommunicationsNanjing 210023China

Covalent organic frameworks(COFs) are attractive porous crystalline materials with extremely high stability, easy functionalization, and open channels, which are expected to be unique ion conductors/transporters in lithium ion batteries(liBs). Despite recent advances, low ion conductivity and low transference number, resulting in low charging/discharging rate, low energy density, and short battery life, are the main issues that limit their direct application as solid electrolytes in liBs. Here, we designed and synthesized a novel polyimide COF, namely, TAPA-PDI-COF, with abundant C=O groups, which has been successfully employed as high-performance solid electrolytes by doping TAPA-PDI-COF and succinonitrile(SN). Both the well-defined nanochannels of COFs and SN confined in the well-aligned channels restricted the free migration of anions, while C=O on COFs and CN groups of SN enhanced li^(+) transport, thus achieving a high ion conductivity of 0.102 m S cm^(-1)at 80 °C and a high lithium-ion transference number of 0.855 at room temperature. According to density functional theory(DFT)calculations, li-ion migration mainly adopted in-plane transport rather than the axial pathway, which may be due to the shorter hopping distances in the planar pathway. The results suggest an effective strategy for the design and development of all-solidstate ionic conductors for achieving high-performance liBs.

关键词： lithium ion batteries(liBs) covalent organic frameworks(COFs) solid-state ion conductors solid-state electrolytes ion conductivity

Data processing and initial results of Chang'e-3 lunar penetrating radar

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Research in Astronomy and Astrophysics 2014年第12期14卷 1623-1632页

作者： Yan Su Guang-You Fang Jian-Qing Feng Shu-Guo Xing Yi-Cai Ji Bin Zhou Yun-Ze Gao Han li Shun Dai Yuan Xiao chun-lai li Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences Institute of Electronics Chinese Academy of Sciences

To improve our understanding of the formation and evolution of the Moon, one of the payloads onboard the Chang＇e-3 （CE-3） rover is Lunar Penetrating Radar （LPR）. This investigation is the first attempt to explore the lunar subsurface structure by using ground penetrating radar with high resolution. We have probed the subsur- face to a depth of several hundred meters using LPR. In-orbit testing, data processing and the preliminary results are presented. These observations have revealed the con- figuration of regolith where the thickness of regolith varies from about 4 m to 6 m. In addition, one layer of lunar rock, which is about 330 m deep and might have been accumulated during the depositional hiatus of mare basalts, was detected.

关键词： space vehicles: instruments: Lunar Penetrating Radar -- techniques:radar astronomy -- methods: data processing -- Moon: lunar subsurface -- Moon:regolith