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arXiv 2024年

作者： Bi, Xiaoming Guo, Zhongkai Zou, Xiaobo Huang, Yong Li, Peijia Cao, Jianfeng Chen, Lue Tang, Wenlin Lau, Yun Kau School of Physical Science and Technology Lanzhou University Lanzhou730000 China Beijing Institute of Space Mechanics and Electricity China Academy of Space Technology Beijing100094 China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai200030 China Key Laboratory of Planetary Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai200030 China Key Laboratory of Electronics and Information Technology for Space System National Space Science Center Chinese Academy of Sciences Beijing100190 China Science and Technology on Aerospace Flight Dynamics Laboratory Beijing Aerospace Control Center Beijing China Institute of Applied Mathematics Morningside Center of Mathematics LSSC Academy of Mathematics and System Science Chinese Academy of Sciences 55 Zhongguancun Donglu Beijing100190 China

Two way ranging data for spacecraft tracking of China’s first Martian mission Tianwen-I is analysed. Shortly before the spacecraft entered the Mars parking orbit, the two way coherent microwave link between the spacecraft and the Earth resembles a long arm gravitational wave interferometer, with both the spacecraft and the Earth regarded as in an approximate free falling state. By carefully selecting and analysing data segments of the time series of the two way ranging data during this time span, a parametric statistical model is built for the data segments and an upper limit for the stochastic gravitational waves background (SGWB) is then estimated within the frequency window 0.1Hz to 0.1 mHz. The upper bound improves considerably on those obtained before. In particular, around the deci-Hz band, there is a three orders improvement on the bound obtained previously by the two way ranging data of the Chang e 3 mission. Scientific applications of the upper bound is then considered and a weak upper bound is worked out for axions which is a promising candidate for ultra light dark matter. Copyright © 2024, The Authors. All rights reserved.

关键词： spacecraft

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Seamless maps of major elements of the Moon:Results from high-resolution geostationary satellite

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Research in Astronomy and Astrophysics 2021年第2期21卷 52-60页

作者： Yu Lu Yun-Zhao Wu Cui Li Jin-Song Ma Wen-Wen Qi Wei Tan Xiao-Man Li Zhi-Cheng Shi Hong-Yan He Shu-Wu Dai Guo Li Feng-Jing Liu Jing-Qiao Wang Xiao-Yan Wang Qi Wang Ling-Jie Meng Key Laboratory of Planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210034China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Hefei 230026China Space Science Institute Macao University of Science and TechnologyMacaoChina School of Geography and Ocean Science Nanjing UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China Beijing Institute of Space Mechanics and Electricity Beijing 100076China Beijing Institute of Spacecraft System Engineering Beijing 100076China China Centre for Resources Satellite Data and Application Beijing 100094China Earth Observation System and Data Center China National Space AdministrationBeijing 100010China

Major elements such as Fe,Ti,Mg,Al,Ca and Si play very important roles in understanding the origin and evolution of the *** maps of these major elements derived from orbital data are based on mosaic images or low-resolution gamma-ray *** hue variations and gaps among orbital boundaries in the mosaic images are not conducive to geological *** paper aims to produce seamless and homogenous distribution maps of major elements using the single-exposure image of the whole lunar disk obtained by China’s high-resolution geostationary satellite,Gaofen-4,with a spatial resolution of500 *** elemental contents of soil samples returned by Apollo and Luna missions are regarded as ground truth,and are correlated with the reflectance of the sampling sites extracted from Gaofen-4 *** final distribution maps of these major oxides are generated with the statistical regression *** these products,the average contents and proportions of the major elements for maria and highlands were estimated and *** results showed that Si O2 and Ti O2 have the highest and lowest fractions in mare and highland areas,***,the relative concentrations of these elements could serve as indicators of geologic processes,e.g.,the obviously asymmetric distributions of Al2 O3,Ca O and Si O2 around Tycho crater may suggest that Tycho crater was formed by an oblique impact from the southwest direction.

关键词： Moon-Data analysis-Imaging spectroscopy

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Halftone spatial frequency domain imaging enables kilohertz high-speed label-free non-contact quantitative mapping of optical properties for strongly turbid media

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Light(science & Applications) 2021年第12期10卷 2518-2530页

作者： Yanyu Zhao Bowen Song Ming Wang Yang Zhao Yubo Fan Beijing Advanced Innovation Center for Biomedical Engineering Key Laboratory for Biomechanics and Mechanobiology of Ministry of EducationSchool of Engineering Medicineand with the School of Biological Science and Medical EngineeringBeihang University100191 BeijingChina Institute of Spacecraft Application System Engineering China Academy of Space Technology100094 BeijingChina Beijing Institute of Spacecraft Engineering 100094 BeijingChina

The ability to quantify optical properties(i.e.,absorption and scattering)of strongly turbid media has major implications on the characterization of biological tissues,fluid fields,and many ***,there are few methods that can provide wide-field quantification of optical properties,and none is able to perform quantitative optical property imaging with high-speed(e.g.,kilohertz)*** we develop a new imaging modality termed halftone spatial frequency domain imaging(halftone-SFDI),which is approximately two orders of magnitude faster than the state-of-the-art,and provides kilohertz high-speed,label-free,non-contact,wide-field quantification for the optical properties of strongly turbid *** method utilizes halftone binary patterned illumination to target the spatial frequency response of turbid media,which is then mapped to optical properties using model-based *** validate the halftone-SFDI on an array of phantoms with a wide range of optical properties as well as in vivo human *** demonstrate with an in vivo rat brain cortex imaging study,and show that halftone-SFDI can longitudinally monitor the absolute concentration as well as spatial distribution of functional chromophores in *** also show that halftone-SFDI can spatially map dual-wavelength optical properties of a highly dynamic flow field at kilohertz ***,these results highlight the potential of halftone-SFDI to enable new capabilities in fundamental research and translational studies including brain science and fluid dynamics.

关键词： optical scattering media

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Mstformer: Motion Inspired Spatial-Temporal Transformer for Vessel Trajectory Prediction

SSRN

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SSRN 2023年

作者： Qiang, Huimin Guo, Zhiyuan Xie, Shiyuan Peng, Xiaodong the Key Laboratory of Electronics and Information Technology for Space System National Space Science Center Chinese Academy of Sciences Beijing100190 China University of Chinese Academy of Sciences Beijing100049 China

Accurate maritime vessel trajectory prediction is essential for safety and efficient port scheduling. Traditionally, such predictions rely on model-based methods, but complex forces and unpredictable marine disturbances impose difficulty on modeling. Recently, the collection of Automatic Identification system (AIS) data has facilitated the advancement of data-driven methods, especially deep learning. However, the limited availability of maritime datasets possibly leads to unreliable results. To address those challenges, this paper presents a novel hybrid approach, MSTFormer. MSTFormer employs a transformer network enhanced with data augmentation and dynamic-aware attention mechanisms to effectively extract dynamic spatial-temporal trajectory features and predict vessel motion accelerations. The predicted positions are then calculated by the accelerations through Euler's method and geodesy principles. Experimental results on real-world datasets show that our strategy not only effectively improves predictive capability but also outperforms backbones on cornering data. The ablation analysis further confirms the efficacy of the proposed method. The code of our experiments is available at https://***/simple316/MSTFormer. © 2023, The Authors. All rights reserved.

关键词： Forecasting

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Architecture analysis for avionics prognostics and health management system

Architecture analysis for avionics prognostics and health ma...

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Fault Detection, Supervision and Safety for Technical Processes (SAFEPROCESS), CAA Symposium on

作者： Runfeng Chen Yang Hu Yanze Hou Qian Xuesen Laboratory of Space Technology China Academy of Space Technology (CAST) Beijing China Science and Technology on Complex Aviation System Simulation Laboratory 9236 Beijing China

ISBN: (纸本)9781665401166

Prognostics and Health Management (PHM) has been researched on for recent years, and extensive studies have been done on hot topics into this field, such as diagnostics, prognostics, and decision making. However, how to evaluate PHM system architecture is still lacking. This is particularly important when designing avionics system equipped with PHM functions. We propose a general, time-variant architecture model that can simulate PHM system. Performance metrics are calculated to quantitatively evaluate the system architecture. This is useful to find differences of architectures in the earlier design stage in engineering. A case study is presented of the use of architecture modelling to show the effectiveness. And future works are discussed.

关键词： Measurement Analytical models system performance Fault detection Decision making systems architecture Aerospace electronics

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Low-Earth Orbital Lifetime Prediction Based on Parameter Sensitivity Analysis and Deep Learning

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IEEE Transactions on Aerospace and Electronic systems 2025年

作者： Chen, Shun-Yi Yang, Zhen Wang, Hua Lu, Lin State Key Laboratory of Space System Operation and Control Changsha410073 China National University of Defense Technology College of Aerospace Science and Engineering Changsha410073 China China Astronaut Research and Training Center Beijing100094 China

This article proposes an intelligent prediction method for the orbital lifetime of resident space objects (RSOs) in low Earth orbit. This method is intended to satisfy the computational efficiency and accuracy requirements when predicting the large-scale RSOs. It helps to analyze the distribution and uncertainty of RSOs' lifetime. First, based on the semi-analytical orbit prediction model, a parameter sensitivity analysis method for the orbital lifetime is proposed, and the parameters that affect the orbital lifetime are investigated. Second, using a fully connected neural network, an orbital lifetime prediction model is established based on deep learning. The hyperparameters of the deep learning model are optimized using the black-winged kite algorithm. Finally, by combining the sensitivity analysis with the deep learning model, an intelligent prediction method is proposed for the rapid prediction of orbital lifetime. simulation results show that the proposed intelligent prediction method accurately determines the orbital lifetime of RSOs and has higher prediction efficiency than the traditional prediction method. The research results provide an effective calculation and analysis tool for predicting the orbital lifetime of large-scale RSOs in the future. © 2025 IEEE.

关键词： Prediction models

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Light from space illuminating the polar silk road

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International Journal of Digital Earth 2022年第1期15卷 2028-2046页

作者： Xiao-Ming Li Yujia Qiu Yacheng Wang Bingqing Huang Haiming Lu Min Chu Han Fu Fengming Hui International Research Center of Big Data for Sustainable Development Goals BeijingPeople’s Republic of China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China Space Star Technology CO. LTDBeijingPeople’s Republic of China COSCO Shipping Specialized Carriers CO. LTDGuangzhouPeople’s Republic of China CMA Earth System Modeling and Prediction Centre (CEMC) BeijingPeople’s Republic of China State Key Laboratory of Severe Weather (LaSW) BeijingPeople’s Republic of China State Key Laboratory of Space-Ground Integrated Information Technology Beijing Institute of Satellite Information EngineeringBeijingPeople’s Republic of China School of Geospatial Engineering and Science Sun Yat-Sen Universityand Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)ZhuhaiPeople’s Republic of China

The rapid decline of Arctic sea ice has been reminding us the significant impacts caused by global ***,the other side of the coin is that this opens a window to utilize the Arctic sea routes in the summer seasons,bringing remarkable economic benefits for ocean transportation between Asia and ***,commercial vessels with low ice classes must tackle substantial environmental challenges in the Arctic sea routes,particularly those caused by variable sea ice,even in the melting ***,the science-based support for shipping safety in the Arctic sea routes is being given more *** satellite remote sensing technology plays a critical role in environmental monitoring in the *** paper reviews state-of-the-art satellite observations on monitoring sea ice and potential applications on supporting shipping activities in the Arctic ***,we introduced a recently developed system based on satellite observations to support the safe transportation of Chinese cargo vessels in the Arctic northern sea route,demonstrating the efforts by both the science and business communities to promote the development of the polar silk road.

关键词： Arctic northern sea route earth observation digital earth sustainable development

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Integrated optimization design of smart morphing wing for accurate shape control

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Chinese Journal of Aeronautics 2021年第1期34卷 135-147页

作者： Xiaojun GU Kaike YANG Manqiao WU Yahui ZHANG Jihong ZHU Weihong ZHANG Unmanned System Research Institute Northwestern Polytechnical UniversityXi'an 710072China State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Poly technical UniversityXi'an 710072China Science and Technology on Space Physics Laboratory China Academy of Launch Vehicle TechnologyBeijing 100076China

Smart morphing wing, which is equipped with smart materials and able to change structural geometry adaptively, can further improve aerodynamic efficiency of aircraft. This paper presents a new integrated layout and topology optimization design for morphing wing driven by shape memory alloys(SMAs). By simultaneously optimizing the layout of smart actuators and topology of wing substrate, the ultimately determined configuration can achieve smooth, continuous and accurate geometric shape changes. In addition, aerodynamic analysis is carried out to compare smart morphing wing with traditional hinged airfoil. Finally, the optimized smart wing structure is constructed and tested to demonstrate and verify the morphing functionality. Application setbacks are also pointed out for further investigation.

关键词： Layout optimization Morphing wing Shape memory alloy Shape morphing Topology optimization

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Progress in quantitative research on the relationship between atmospheric oxidation and air quality

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Journal of Environmental sciences 2023年第1期123卷 350-366页

作者： Yuesi Wang Xin Jin Zirui Liu Gehui Wang Guiqian Tang Keding Lu Bo Hu Shanshan Wang Guohui Li Xinqin An Chao Wang Qihou Hu Lingyan He Fenfen Zhang Yuanhang Zhang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China 3 State Key Joint Laboratory or Environmental Simul ation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Key Lab of Geophysical Information System of the Ministry of Education School of Geographic SciencesEast China Normal UniversityShanghai 200241China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 201203China Key Lab of Aerosol Chemistry and Physics State Key Laboratory of Loess and Quaternary GeologyInstitute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Institute of Atmospheric Composition and Environmental Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China Key Lab of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China

Atmospheric oxidizing capacity(AOC)is an essential driving force of troposphere chemistry and self-cleaning,but the definition of AOC and its quantitative representation remain *** by national demand for air pollution control in recent years,Chinese scholars have carried out studies on theories of atmospheric chemistry and have made considerable progress in AOC *** paper will give a brief review of these ***,AOC indexes were established that represent apparent atmospheric oxidizing ability(AOIe)and potential atmospheric oxidizing ability(AOIp)based on aspects of macrothermodynamics and microdynamics,respectively.A closed study refined the quantitative contributions of heterogeneous chemistry to AOC in beijing,and these AOC methods were further applied in beijing-Tianjin-Hebei and key areas across the *** addition,the detection of ground or vertical profiles for atmospheric OH·,HO_(2)·,NO_(3)·radicals and reservoir molecules can now be obtained with domestic instruments in diverse ***,laboratory smoke chamber simulations revealed heterogeneous processes involving reactions of O_(3)and NO_(2),which are typical oxidants in the surface/interface atmosphere,and the evolutionary and budgetary implications of atmospheric oxidants reacting under multispecies,multiphase and multi-interface conditions were ***,based on the GRAPES-CUACE adjoint model improved by Chinese scholars,simulations of key substances affecting atmospheric oxidation and secondary organic and inorganic aerosol formation have been *** numerical simulations of AOIe and AOIp were performed,and regional coordination of AOC was *** optimized plan for controlling O_(3)and PM2.5was analyzed by scenario simulation.

关键词： Atmospheric oxidizing capacity(AOC) Quantitative index Free radicals Observation and modeling Air quality

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Regulation of Shock Response in Cage-Like High-Energy-Density Materials: Competition between Strain Energy and Structural Symmetry

SSRN

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SSRN 2025年

作者： Song, Qingguan Meng, Li Jiang, Shengli Zhang, Lei Mo, Zeyao Institute of Applied Physics and Computational Mathematics Beijing100088 China CAEP Software Center for High Performance Numerical Simulation Beijing100088 China Institute of Chemical Materials China Academy of Engineering Physics Mianyang621999 China School of Materials Science & Engineering Beijing Institute of Technology Beijing100081 China State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of Technology Beijing100081 China

The cage-like structures provide a unique combination of strain energy for enhanced energy storage and hyperstatic constraints to stabilize the system, positioning them as promising pioneers in advancing high-energy-density materials (HEDMs). However, the shock response of cage-like HEDMs is highly complex and exhibits significant variability, posing a grand challenge in the underlying mechanisms. This study reveals that the shock response of cage-like HEDMs is regulated by the interplay between strain energy and structural symmetry, and introduces a physical model to quantitatively describe how they determine shock stability. The investigated systems include a comprehensive series of cage-like polynitrocubane HEDMs, with each carbon atom in the backbone progressively functionalized with nitro groups. Ab initio molecular dynamics (AIMD) simulations were employed to simulate dynamic and kinetic responses at shock velocities ranging from 8 km/s to 11 km/s, with validation provided by consistent Hugoniot curves that align with reported experimental data. Nitro substituents at the carbon-based cage structure, recognized as explosion functional groups, were found to substantially increase the system's strain energy. However, an increasing number of nitro substituents also intensified electrostatic repulsion among oxygen lone pairs, which weakens structural integrity and renders the material more susceptible to disassembly under shock conditions. Conversely, structural symmetry—including both the cage-like molecular conformation and spatial packing within the crystal lattice—was found to mitigate these destabilizing effects, effectively balancing the trade-off between energy storage and structural stability. Based on these findings, we propose a physical model that captures the essential factors driving shock initiation in cage-like HEDMs, offering new insights to inform the design and application of novel advanced HEDMs. © 2025, The Authors. All rights reserved.

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