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Data processing and error analysis for the CE-1 Lunar microwave radiometer

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Research in Astronomy and Astrophysics 2013年第3期13卷 359-372页

作者： Jian-Qing Feng Yan Su Jian-Jun Liu yong-liao zou Chun-Lai Li National Astronomical Observatories Chinese Academy of Sciences

The microwave radiometer （MRM） onboard the Chang＇ E-1 （CE-I） lu- nar orbiter is a 4-frequency microwave radiometer, and it is mainly used to obtain the brightness temperature （TB） of the lunar surface, from which the thickness, temperature, dielectric constant and other related properties of the lunar regolith can be derived. The working mode of the CE-1 MRM, the ground calibration （including the official calibration coefficients）, as well as the acquisition and processing of the raw data are introduced. Our data analysis shows that TB increases with increasing frequency, decreases towards the lunar poles and is significantly affected by solar illumination. Our analysis also reveals that the main uncertainty in TB comes from ground calibration.

关键词： space vehicles -- instruments: microwave radiometer -- Moon: bright-ness temperature -- method: data processing -- error analysis

Reflectance conversion methods for the VIS/NIR imaging spectrometer aboard the Chang'E-3 lunar rover: based on ground validation experiment data

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Research in Astronomy and Astrophysics 2013年第7期13卷 862-874页

作者： Bin Liu Jian-Zhong Liu Guang-Liang Zhang Zong-Cheng Ling Jiang Zhang Zhi-Ping He Ben-yong Yang yong-liao zou National Astronomical Observatories Chinese Academy of Sciences School of Space Science and Physics Shandong University at Weihai Graduate University of Chinese Academy of Sciences Shanghai Institute of Technical Physics Chinese Academy of Sciences Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences

The second phase of the Chang＇E Program （also named Chang＇E-3） has the goal to land and perform in-situ detection on the lunar surface. A VIS/NIR imaging spectrometer （VNIS） will be carded on the Chang＇E-3 lunar rover to detect the distri-bution of lunar minerals and resources. VNIS is the first mission in history to perform in-situ spectral measurement on the surface of the Moon, the reflectance data of which are fundamental for interpretation of lunar composition, whose quality would greatly affect the accuracy of lunar element and mineral determination. Until now, in-situ de-tection by imaging spectrometers was only performed by rovers on Mars. We firstly review reflectance conversion methods for rovers on Mars （Viking landers, Pathfinder and Mars Exploration rovers, etc）. Secondly, we discuss whether these conversion methods used on Mars can be applied to lunar in-situ detection. We also applied data from a laboratory bidirectional reflectance distribution function （BRDF） using simu- lated lunar soil to test the availability of this method. Finally, we modify reflectance conversion methods used on Mars by considering differences between environments on the Moon and Mars and apply the methods to experimental data obtained from the ground validation of VNIS. These results were obtained by comparing reflectance data from the VNIS measured in the laboratory with those from a standard spectrometer obtained at the same time and under the same observing conditions. The shape and amplitude of the spectrum fits well, and the spectral uncertainty parameters for most samples are within 8%, except for the ilmenite sample which has a low albedo. In conclusion, our reflectance conversion method is suitable for lunar in-situ detection.

关键词： instrumentation: detectors - lunar in-situ detection: VNIS - re-flectance conversion: BRDF

Image Fusion Based on Bioinspired Rattlesnake Visual Mechanism Under Lighting Environments of Day and Night Two Levels

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Journal of Bionic Engineering 2024年第3期21卷 1496-1510页

作者： yong Wang Hongmin zou College of Communication Engineering Jilin UniversityChangchun130012China

This study,grounded in Waxman fusion method,introduces an algorithm for the fusion of visible and infrared images,tailored to a two-level lighting environment,inspired by the mathematical model of the visual receptive field of rattlesnakes and the two-mode cells'*** research presented here is segmented into three *** the first segment,we design a preprocessing module to judge the ambient light intensity and divide the lighting environment into two levels:day and *** second segment proposes two distinct network structures designed specifically for these daytime and nighttime *** the daytime images,where visible light information is predominant,we feed the ON-VIS signal and the IR-enhanced visual signal into the central excitation and surrounding suppression regions of the ON-center receptive field in the B channel,***,for nighttime images where infrared information takes precedence,the ON-IR signal and the Visual-enhanced IR signal are separately input into the central excitation and surrounding suppression regions of the ON-center receptive field in the B *** outcome is a pseudo-color fused *** third segment employs five different no-reference image quality assessment methods to evaluate the quality of thirteen sets of pseudo-color images produced by fusing infrared and visible *** images are then compared with those obtained by six other methods cited in the relevant *** empirical results indicate that this study's outcomes surpass the comparative results in terms of average gradient and spatial *** one or two sets of fused images underperformed in terms of standard deviation and entropy when compared to the control *** sets of fused images did not perform as well as the comparison in the QAB/F *** conclusion,the fused images generated through the proposed method show superior performance in terms of scene detail,visual perception,and image sharpness

关键词： Rattlesnake Visible image Infrared image Daylight Bionic

Time series data correction for the Chang'E-1 gamma-ray spectrometer

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Research in Astronomy and Astrophysics 2011年第6期11卷 737-750页

作者： Li-Yan Zhang yong-liao zou Jian-Zhong Liu Jian-Jun Liu Ji Shen Ling-Li Mu Xin Ren Wei-Bin Wen Chun-Lai Li National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Graduate University of Chinese Academy of Sciences Beijing 100049China

The main goal of the gamma-ray spectrometer（GRS） onboard Chang＇E1（CE-1） is to acquire global maps of elemental abundances and their distributions on the moon,since such maps will significantly improve our understanding of lunar formation and *** derive the elemental maps and enable research on lunar formation and evolution,raw data that are received directly from the spacecraft must be converted into time series corrected gamma-ray *** data correction procedures for the CE-1 GRS time series data are thoroughly *** processing procedures to create the time series gamma-ray spectra described here include channel processing,optimal data selection,energy calibration,gain correction,dead time correction,geometric correction,orbit altitude normalization,eliminating unusable data and galactic cosmic ray ***,descriptions are also given on data measurement uncertainties,which will help the interested scientists to understand and estimate various uncertainties associated with the above data processing.

关键词： instrumentation:spectrographs(gamm-ray spectrometer)-gammarays:observations-methods:data analysis

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

A visible-light-assisted Pd/TiO_(2)gas sensor with carbon nanotubes electrodes for trace formaldehyde detection

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Rare Metals 2024年第1期43卷 257-266页

作者： Can Liu Qiao-Qiao zou Bin Liu yong Zhang School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China Hunan Institute of Advanced Sensing and Information Technology Xiangtan UniversityXiangtan 411105China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China

Owing to the ppb-level detection standard toward the toxic and harmful gas,the detection of trace gases has become an important subject in the field of indoor environment ***,the traditional resistive gas sensors hardly meet the requirement due to the weak signal generated by trace gas molecules that are difficult to ***,a visible-light-assisted Pd/TiO_(2)gas sensor is proposed to endow the effective detection of trace formaldehyde(HCHO)gas without heating *** from the enhanced photocatalytic properties of TiO_(2)by Pd decoration,the visible-light-assisted Pd/TiO_(2)gas sensor can detect the HCHO gas as low as80×10^(–9)at room *** successful preparation of nanoscale TiO_(2)sensing layer is facilitated by the ultrathin carbon nanotube interdigital electrode in the gas sensor,which avoids the discontinuity of the sensing layer caused by the excessive thickness of the traditional metal *** addition,the whole preparation process of the Pd/TiO_(2)gas sensor with carbon nanotube electrodes is compatible with mainstream CMOS fabrication technology,which is expected to realize the batch fabrication and micro-integrated application of gas *** is expected that our work can provide a new strategy for the batch preparation of high-performance trace HCHO gas sensors and their future applications in portable electronic devices such as smartphones.

关键词： Visible-light-assisted gas sensor Pd/TiO_(2) Trace HCHO detection Carbon nanotubes electrodes

Data processing and initial results from the CE-3 Extreme Ultraviolet Camera

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Research in Astronomy and Astrophysics 2014年第12期14卷 1664-1673页

作者： Jian-Qing Feng Jian-Jun Liu Fei He Wei Yan Xin Ren Xu Tan Ling-Ping He Bo Chen Wei Zuo Wei-Bin Wen Yan Su yong-liao zou Chun-Lai Li Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of Sciences Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences

The Extreme Ultraviolet Camera （EUVC） onboard the Chang＇e-3 （CE-3） lander is used to observe the structure and dynamics of Earth＇s plasmasphere from the Moon. By detecting the resonance line emission of helium ions （He＋） at 30.4 nm, the EUVC images the entire plasmasphere with a time resolution of 10 min and a spatial resolution of about 0.1 Earth radius （RE） in a single frame. We first present details about the data processing from EUVC and the data acquisition in the commissioning phase, and then report some initial results, which reflect the basic features of the plas- masphere well. The photon count and emission intensity of EUVC are consistent with previous observations and models, which indicate that the EUVC works normally and can provide high quality data for future studies.

关键词： space vehicles: instruments: Extreme Ultraviolet Camera -- Earth: plas-masphere -- method: data processing

Microstructured Cantilever Probe on Optical Fiber Tip for Microforce Sensor

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Photonic Sensors 2024年第2期14卷 89-99页

作者： Famei WANG Changrui liao Mengqiang zou Dejun LIU Haoqiang HUANG Chao LIU Yiping WANG Shenzhen Key Laboratory of Ultrafast Laser Micro/Nano Manufacturing Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education/Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Photonic Devices and Sensing Systems for Internet of Things Guangdong and Hong Kong Joint Research Centre for Optical Fibre SensorsState Key Laboratory of Radio Frequency Heterogeneous IntegrationShenzhen UniversityShenzhen 518060China School of Electronics Science Northeast Petroleum UniversityDaqing 163318China

Benefiting from the great advances of the femtosecond laser two-photon polymerization(TPP)technology,customized microcantilever probes can be accurately 3-dimensional(3D)manufactured at the nanoscale size and thus have exhibited considerable potentials in the fields of microforce,micro-vibration,and microforce *** this work,a controllable microstructured cantilever probe on an optical fiber tip for microforce detection is demonstrated both theoretically and *** static performances of the probe are firstly investigated based on the finite element method(FEM),which provides the basis for the structural *** proposed cantilever probe is then 3D printed by means of the TPP *** experimental results show that the elastic constant k of the proposed cantilever probe can be actively tuned from 2.46N/m to 62.35N/*** force sensitivity is 2.5nm/μN,the Q-factor is 368.93,and the detection limit is ***,the mechanical properties of the cantilever probe can be flexibly adjusted by the geometric configuration of the ***,it has an enormous potential for matching the mechanical properties of biological samples in the direct contact mode.

关键词： Optical fiber sensor microforce sensing microstructured cantilever two-photon polymerization

Economical Quadrupedal Multi-Gait Locomotion via Gait-Heuristic Reinforcement Learning

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Journal of Bionic Engineering 2024年第4期21卷 1720-1732页

作者： Lang Wei Jinzhou zou Xi Yu Liangyu Liu Jianbin liao Wei Wang Tong Zhang School of Power and Mechanical Engineering Wuhan UniversityLuojiashanWuhan430072HubeiChina State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityLuojiashanWuhan430072HubeiChina

In order to strike a balance between achieving desired velocities and minimizing energy consumption,legged animals have the ability to adopt the appropriate gait pattern and seamlessly transition to another if *** ability makes them more versatile and efficient when traversing natural terrains,and more suitable for long *** the same way,it is meaningful and important for quadruped robots to master this *** achieve this goal,we propose an effective gait-heuristic reinforcement learning framework in which multiple gait locomotion and smooth gait transitions automatically emerge to reach target velocities while minimizing energy *** incorporate a novel trajectory generator with explicit gait information as a memory mechanism into the deep reinforcement learning *** allows the quadruped robot to adopt reliable and distinct gait patterns while benefiting from a warm start provided by the trajectory ***,we investigate the key factors contributing to the emergence of multiple gait *** tested our framework on a closed-chain quadruped robot and demonstrated that the robot can change its gait patterns,such as standing,walking,and trotting,to adopt the most energy-efficient gait at a given ***,we deploy our learned controller to a quadruped robot and demonstrate the energy efficiency and robustness of our method.

关键词： Legged robots Deep reinforcement learning Central pattern generator Quadrupedal gait