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Application of MoS_(2)in the space environment:a review

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Frontiers of Mechanical Engineering 2023年第3期18卷 47-77页

作者： Menghe ZHOU Ruiting TONG Tao ZHANG Geng LIU Shaanxi Engineering Laboratory for Transmissions and Controls Northwestern Polytechnical UniversityXi'an 710072China CALT China Academy of Launch Vehicle TechnologyBejing 100076China

A considerable portion of space mechanism failures are related to space tribological *** welding in high vacuum;surface erosion and collision damage caused by various radiations,high temperature oxidation under atomic oxygen(AO)bombardment;and thermal stress caused by temperature alternation all alter the physical,chemical,and friction properties of *** particular,the space vibration caused by alternating temperatures and microgravity environments can alter the motion of the contact body,further affecting its friction *** the friction properties of contact surfaces in the space environment is an important way to extend the service life of *** lubricants can no longer meet the lubrication requirements of the space *** study describes the characteristics of the space environment and the applications of solid *** friction properties of MoS_(2),a solid lubricant widely used in space,are *** synergistic lubrication of MoS_(2)with surface textures or metals is *** in research on the friction properties of collision sliding contacts in the space environment are *** combination of MoS_(2)and soft metals with surface textures is introduced to reduce the effects of vibration environments on the friction properties of moving parts in space ***,the challenges and future research interests of MoS_(2)films in space tribology are presented.

关键词： MoS_(2) soft metal space environment surface texture synergistic effect vibration

An Improved HVQ Algorithm for Compression and Rendering of space environment Volume Data with Multi-correlated Variables

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空间科学学报 2023年第4期43卷 780-785页

作者： BAO Lili CAI Yanxia WANG Rui ZOU Yenan SHI Liqin State Key Laboratory of space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190 Key Laboratory of Science and Technology on environmental space Situation Awareness Chinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

Volume visualization can not only illustrate overall distribution but also inner structure and it is an important approach for space environment *** environment simulation can produce several correlated variables at the same ***,existing compressed volume rendering methods only consider reducing the redundant information in a single volume of a specific variable,not dealing with the redundant information among these *** space environment volume data with multi-correlated variables,based on the HVQ-1d method we propose a further improved HVQ method by compositing variable-specific levels to reduce the redundant information among these *** volume data associated with each variable is divided into disjoint blocks of size 43 *** blocks are represented as two levels,a mean level and a detail *** variable-specific mean levels and detail levels are combined respectively to form a larger global mean level and a larger global detail *** both global levels,a splitting based on a principal component analysis is applied to compute initial ***,LBG algorithm is conducted for codebook refinement and *** further take advantage of progressive rendering based on GPU for real-time interactive *** method has been tested along with HVQ and HVQ-1d on high-energy proton flux volume data,including>5,>10,>30 and>50 MeV integrated proton *** results of our experiments prove that the method proposed in this paper pays the least cost of quality at compression,achieves a higher decompression and rendering speed compared with HVQ and provides satisficed fidelity while ensuring interactive rendering speed.

关键词： Compressed volume rendering Multi-correlated variables space environment Vector quantization GPU programming

Nonlinear dynamics of flexible tethered satellite system subject to space environment

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Applied Mathematics and Mechanics(English Edition) 2016年第4期37卷 485-500页

作者： Bensong YU Dongping JIN Hao WEN State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics

The paper studies the nonlinear dynamics of a flexible tethered satellite system subject to space environments, such as the J2 perturbation, the air drag force, the solar pressure, the heating effect, and the orbital eccentricity. The flexible tether is modeled as a series of lumped masses and viscoelastic dampers so that a finite multi- degree-of-freedom nonlinear system is obtained. The stability of equilibrium positions of the nonlinear system is then analyzed via a simplified two-degree-freedom model in an orbital reference frame. In-plane motions of the tethered satellite system are studied numerically, taking the space environments into account. A large number of numerical simulations show that the flexible tethered satellite system displays nonlinear dynamic characteristics, such as bifurcations, quasi-periodic oscillations, and chaotic motions.

关键词： tethered satellite system flexible tether model space environment stability,nonlinear dynamics

Analysis of the influence of micro satellite's development on space environment

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Journal of Beijing Institute of Technology 2016年第S2期25卷 185-189页

作者：魏峻赵导黄明 State Key Laboratory of Astronautic Dynamics

In recent years,a large quantity of micro satellite has been launched into space,which makes the space environment of low Earth orbit(LEO) more *** reduce the negative influence bringing by micro satellite,the present situation of space environment and micro satellite are *** on the analysis of the relationship between micro satellite and space debris,especially the potential effect of micro satellite on monitoring and mitigation of space debris,some advices are presented.

关键词： micro satellite space environment space debris mitigation

Diversity and Stability Study on Rice Mutants Induced in space environment

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Genomics, Proteomics & Bioinformatics 2008年第1期6卷 51-60页

作者： Wei-Hong Lu Xin-Zhu Wang Qi Zheng Shuang-Hong Guan Ping Xin Ye-Qing Sun Department of Astronautic Engineering Harbin Institute of Technology Harbin 150001 China Biochemistry Department Imperial College London South Kensington Campus London SW7 2AZ UK Institute of environmental Systems Biology Dalian Maritime University Dalian 116026 China.

To further study the characteristics of changes on the molecular level of rice mutants induced in space environment, we analyzed proteins in leaves and seeds of four rice mutants （two high-tillering and two low-tillering） in the 8th and 9th generations after a 15-day spaceflight, and compared with their ground controls by two-dimentional polyacrylamide gel electrophoresis and reverse phase liquid chromatography （RPLC）. In addition, the albumin, globulin, prolamine, glutelin, and amylose of the mutant seeds were analyzed by RPLC and ultra-violet spectrometry. The results showed that the low-abundance proteins of leaves in the peak tillering stage are more likely to he induced compared with their corresponding controls. The albumin, globulin, and prolamine of the mutant seeds revealed changes when compared with their controls, and the characteristics of changes in different mu- tants were stably inherited in the 8th and 9th generations, suggesting that they can be used as biomarkers to identity the mutants induced by spaceflight. Moreover, two proteins （SSP9111 and SSP6302） were found to be expressed with high intensity （two-fold change） in different mutants, which were both correlated with photosystem according to mass spectrometry and database searching.

关键词： space environment rice mutant proteomics

Large-scale spatial data visualization method based on augmented reality

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 132-147页

作者： Xiaoning QIAO Wenming XIE Xiaodong PENG Guangyun LI Dalin LI Yingyi GUO Jingyi REN Key Laboratory of Electronics and Information Technology for space Systems National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Ordnance Science and Research Academy of China Beijing 100089China

Background A task assigned to space exploration satellites involves detecting the physical environment within a certain ***,space detection data are complex and *** data are not conducive for researchers'visual perceptions of the evolution and interaction of events in the space *** A time-series dynamic data sampling method for large-scale space was proposed for sample detection data in space and time,and the corresponding relationships between data location features and other attribute features were established.A tone-mapping method based on statistical histogram equalization was proposed and applied to the final attribute feature *** visualization process is optimized for rendering by merging materials,reducing the number of patches,and performing other *** The results of sampling,feature extraction,and uniform visualization of the detection data of complex types,long duration spans,and uneven spatial distributions were *** real-time visualization of large-scale spatial structures using augmented reality devices,particularly low-performance devices,was also *** The proposed visualization system can reconstruct the three-dimensional structure of a large-scale space,express the structure and changes in the spatial environment using augmented reality,and assist in intuitively discovering spatial environmental events and evolutionary rules.

关键词： Large-scale spatial data analysis Visual analysis technology Augmented reality 3D reconstruction space environment

Analysis of the internal charging data in medium earth orbit with numerical simulation and ground experiment

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Science China(Technological Sciences) 2022年第4期65卷 977-986页

作者： SONG SiYu CHEN HongFei YU XiangQian ZOU Hong ZONG QiuGang CHEN Ao SHI WeiHong YE YuGuang Institute of space Physics and Applied Technology School of Earth and Space SciencesPeking UniversityBeijing 100871China

The deep dielectric charging effect monitor(DDCEM)has been designed to study the internal charging effect by measuring the charging currents and potentials inside the *** is equipped on three Chinese navigation satellites in a circular medium earth orbit(MEO)with 22000 km average height and 55°*** simulation based on the Geant4-RIC method was used to evaluate the data of *** data during May to November 2019 on one of the three satellites show that the charging currents of DDCEM were negatively enhanced when the satellite moved into the outer radiation *** currents reached the negative maximum during a significant electron enhancement in September *** currents were also detected besides negative currents that were caused by the deposition of electrons in the *** causation of positive currents in the space environment may be that the low-energy electrons cannot penetrate the satellite skin and make it charging to negative potential,the reference ground of DDCEM that is connected to the satellite skin drops below zero by the low-energy electrons so that the output currents turn to *** experiment was used to simulate the causation of positive currents and the result verified our theory.

关键词： deep dielectric charging effect monitor internal charging effect charging currents and potentials medium earth orbit space environment

Satellite breakup behaviors and model under the hypervelocity impact and explosion:A review

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Defence Technology(防务技术) 2023年第9期27卷 284-307页

作者： Si-yuan Ren Zi-zheng Gong Qiang Wu Guang-ming Song Qing-ming Zhang Pin-liang Zhang Chuan Chen Yan Cao Beijing Institute of spacecraft environment Engineering China Academy of Space TechnologyBeijing100094China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

The primary causes of satellite breakups are hypervelocity impact and explosion,the research on satellite breakup can be used not only to evaluate the influence of breakup event on the space environment,but also to trace whether the satellite has been deliberately *** is of great significance in both civil and military *** study of satellite breakup behaviors and model is reviewed to summarize the research progress and insufficiency in recent decades,including the satellite breakup experiment,measurement and characterization of fragments,distribution characteristics of breakup fragments,satellite breakup model,*** classical studies are introduced in detail,and the limitations of the current research are pointed *** to the current research results,the contemporary challenges and future directions for satellite breakup study are *** research on satellite breakup is developing in two directions:the miniaturization of satellite size and the complexity of satellite *** study on satellite breakup needs to be explored and deepened on improving the experimental launch speed,expanding the model application range and breakup revealing the results under combined effect of impact and explosion.

关键词： Satellite breakup space environment Distribution characteristics Hypervelocity impact Explosion

Development of High-energy Particle Detectors for space Exploration

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空间科学学报 2022年第6期42卷 1171-1184页

作者： YANG Zhe SHEN Guohong JING Tao National space Science Center Chinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049 Beijing Key Laboratory of space environment Exploration Beijing 100190 Key Laboratory of Science and Technology on space environment Situational Awareness Chinese Academy of SciencesBeijing 100190

space environment exploration is a hot topic *** scope of space exploration ranges from near-Earth space to the moon,other planets in the solar system,and even the heliosphere and interplanetary *** is used for various crucial applications,including aerospace technology development,space weather research,understanding the origin and evolution of the universe,searching for extraterrestrial life,and finding human livable *** China’s space environment exploration started late,its progress has been *** is gradually narrowing the gap with advanced countries and may eventually lead the world in space *** article briefly reviews the development history of China’s space environmental detectors.

关键词： High-energy particle detectors Near-Earth space exploration Lunar exploration space environment