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Space advanced technology demonstration satellite

Science China(Technological Sciences) 2024年第1期67卷 240-258页

作者： ZHANG XiaoFeng CHEN Wen ZHU XiaoCheng MENG Na HE JunWang BI XingZi ZHANG YongHe SHI Qi LI Fei LIU Rui FENG ZhengGong LIU Liu LI JinSong WU HaiChen XU DongXiao LI TaiJie HUANG JiangJiang LIU Shuo LI TianTong YU XianSheng GAO Yang ZHOU Heng ban hanyu ZHANG YanLi ZHANG YueTing YANG YingQuan HE Tao DUAN XuLiang CHEN Xin WANG YaMin SUN AnTai ZHANG KuoXiang SUN Ying WANG YaoBin FAN ChengCheng XIONG ShaoLin LI XinQiao WEN XiangYang LING ZhiXing SUN XiaoJin ZHANG Chen BAI XianYong WANG ZhanShan DENG YuanYong TIAN Hui YANG JianFeng XUE HongBo SANG Peng LIU JinGuo ZHENG HuiLong ZHU Xiang HE JianWu LI Hui XU LuXiang XU ShuYan CHEN WenWu LIU ZhenDong WANG ZhaoLi MAO XiangLong GAO Rong LI ZongXuan DING GuoPeng WANG XinYu DOU RunJiang WENG LuBin LUO Hao WANG YaPing LIANG XianFeng FANG ZiRuo Innovation Academy for Microsatellites Chinese Academy of SciencesShanghai 201203China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China National Astronomical Observatory of China Beijing 100101China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083China Institute of Precision Optical Engineering School of Physics Science and EngineeringTongji UniversityShanghai 200092China School of Earth and Space Sciences Peking UniversityBeijing 100871China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’an 710119China National Space Science Center Chinese Academy of SciencesBeijing 100190China Shenyang Institute of Automation Chinese Academy of SciencesShenyang 110016China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China Shanghai Institute of Organic Chemistry Chinese Academy of SciencesShanghai 200032China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China Nanyang Technological University Singapore 569830Singapore Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023China Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing 100049China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Institute of Semiconductors Chinese Academy of SciencesBeijing 100083China Institute of Automation Chinese Academy of SciencesBeijing 100190China School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310058China

The Space Advanced Technology demonstration satellite(SATech-01),a mission for low-cost space science and new technology experiments,organized by Chinese Academy of Sciences(CAS),was successfully launched into a Sun-synchronous orbit at an altitude of~500 km on July 27,2022,from the Jiuquan Satellite Launch *** as an experimental platform for space science exploration and the demonstration of advanced common technologies in orbit,SATech-01 is equipped with 16 experimental payloads,including the solar upper transition region imager(SUTRI),the lobster eye imager for astronomy(LEIA),the high energy burst searcher(HEBS),and a High Precision Magnetic Field Measurement System based on a CPT Magnetometer(CPT).It also incorporates an imager with freeform optics,an integrated thermal imaging sensor,and a multi-functional integrated imager,*** paper provides an overview of SATech-01,including a technical description of the satellite and its scientific payloads,along with their on-orbit performance.

关键词： SATech-01 spacecraft design scientific instruments on-orbit performance

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Identification of partial differential equations from noisy data with integrated knowledge discovery and embedding using evolutionary neural networks

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 90-97页

作者： hanyu Zhou Haochen Li Yaomin Zhao HEDPS Center for Applied Physics and Technologyand College of EngineeringPeking UniversityBeijing 100871China State Key Laboratory for Turbulence and Complex Systems College of EngineeringPeking UniversityBeijing 100871China

Identification of underlying partial differential equations(PDEs)for complex systems remains a formidable *** the present study,a robust PDE identification method is proposed,demonstrating the ability to extract accurate governing equations under noisy conditions without prior ***,the proposed method combines gene expression programming,one type of evolutionary algorithm capable of generating unseen terms based solely on basic operators and functional terms,with symbolic regression neural *** networks are designed to represent explicit functional expressions and optimize them with data *** particular,the specifically designed neural networks can be easily transformed to physical constraints for the training data,embedding the discovered PDEs to further optimize the metadata used for iterative PDE *** proposed method has been tested in four canonical PDE cases,validating its effectiveness without preliminary information and confirming its suitability for practical applications across various noise levels.

关键词： PDE discovery Gene Expression Programming Deep Learning Knowledge embedding

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Sequestration of helium and xenon via iron-halide compounds in early Earth

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Matter and Radiation at Extremes 2024年第3期9卷 83-88页

作者： Jurong Zhang hanyu Liu Changfeng Chen Yanming Ma Key Laboratory of Material Simulation Methods and Software of Ministry of Education and State Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China School of Physics and Electronics Shandong Normal UniversityJinan 250014China International Center of Future Science Jilin UniversityChangchun 130012China Department of Physics and Astronomy University of NevadaLas VegasNevada 89154USA

The terrestrial abundance anomalies of helium and xenon suggest the presence of deep-Earth reservoirs of these elements,which has led to great interest in searching for materials that can host these usually unreactive ***,using an advanced crystal structure search approach in conjunction with first-principles calculations,we show that several Xe/He-bearing iron halides are thermodynamically stable in a broad region of P–T phase space below 60 *** results present a compelling case for sequestration of He and Xe in the early Earth and may suggest their much wider distribution in the present Earth than previously *** findings offer insights into key material-based and physical mechanisms for elucidating major geological phenomena.

关键词： halide searching insight

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Miniaturized, Wide Stopband Filter Based on Shielded Capacitively Loaded SIW Resonators

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Chinese Journal of Electronics 2024年第2期33卷 456-462页

作者： Yan ZHENG hanyu TIAN Yuandan DONG University of Electronic Science and Technology of China (UESTC)

Based on the full-mode capacitively loaded substrate integrated waveguide（SIW） resonator and the miniaturized shielded half-mode capacitively loaded SIW（S-HMCSIW） cavities, a novel compact high-performance filter is proposed. The footprint of the half-mode SIW（HMSIW） is further reduced due to the application of the capacitive-loading technique. By applying cross coupling, the proposed SIW filter's transmission zero enhances the stopband rejection and shows excellent selectivity. For the bandpass filter, the measured |S21| and |S11| are better than 1.09 d B and-14 d B, respectively. And a 3-d B fractional bandwidth（FBW） of 9.14–10.76 GHz（FBW=16.2%）is also observed. The filter achieves a wide stopband with a-20 d B out-of-band rejection up to 2.69f0（f0= 10 GHz）,with a size of 0.39λg× 0.51λgonly. Good agreement between measurement and simulation is obtained.

关键词： band-pass filters Wireless communication Couplings Resonator filters Microwave theory and techniques Filtering theory Passband

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Ignition processes and characteristics of charring conductive polymers with a cavity geometry in precombustion chamber for applications in micro/nano satellite hybrid rocket motors

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Defence Technology（防务技术） 2024年第2期32卷 55-66页

作者： Zhiyuan Zhang hanyu Deng Wenhe Liao Bin Yu Zai Yu Nanjing University of Science and Technology Nanjing 210094China

The arc ignition system based on charring polymers has advantages of simple structure,low ignition power consumption and multiple ignitions,which bringing it broadly application prospect in hybrid propulsion system of micro/nano ***,charring polymers alone need a relatively high input voltage to achieve pyrolysis and ignition,which increases the burden and cost of the power system of micro/nano satellite in practical *** conductive substance into charring polymers can effectively decrease the conducting voltage which can realize low voltage and low power consumption repeated ignition of arc ignition *** this paper,a charring conductive polymer ignition grain with a cavity geometry in precombustion chamber,which is composed of PLA and multiwall carbon nanotubes(MWCNT)was *** detailed ignition processes were analyzed and two different ignition mechanisms in the cavity of charring conductive polymers were *** ignition characteristics of charring conductive polymers were also investigated at different input voltages,ignition grain structures,ignition locations and injection schemes in a visual ignition *** results demonstrated that the ignition delay and external energy required for ignition were inversely correlated with the voltages applied to ignition ***,the incremental depth of cavity shortened the ignition delay and external energy required for ignition while accelerated the propagation of *** the depth of cavity increased from 2 to 6 mm(at 50 V),the time of flame propagating out of ignition grain changed from 235.6 to 108 ms,and values of mean ignition delay time and mean external energy required for ignition decreased from 462.8 to 320 ms and 16.2 to 10.75 J,*** rear side of the cavity was the ideal ignition position which had a shorter ignition delay and a faster flame propagation speed in comparison to other ignition *** to direct injection scheme,swirlin

关键词： Micro/nano satellite hybrid propulsion Arc ignition Charring conductive polymer Ignition mechanism Ignition characteristic Repeated ignition

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Effects of the nozzle structure and fluidized gas composition on the gas-particle two-phase jet characteristic in a powder fuel scramjet

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Particuology 2024年第9期92卷 166-179页

作者： Changfei Zhuo Hongming Ding Xiaobin Ren hanyu Deng Xiong Chen School of Mechanical and Engineering Key Laboratory of Special Engine TechnologyMinistry of EducationNanjing University of Science and TechnologyNanjing210094China Department of Mechanical Engineering National University of Singapore9 Engineering Drive 1Singapore117576 Shanxi North Xing'an Chemical Industry Co. Ltd.Taiyuan030008China

The interaction between nozzle design and fluidization gas composition significantly influences the dynamics within a powder fuel scramjet's combustion *** investigate this relationship,an experimental study utilized high-speed shadow imaging technology to explore the macroscopic aspects of powder fuel *** investigation examined various convergence angles,nozzle throat lengths,and fluidized gas *** findings include:During jet development,powder fuel initially concentrates near the axis,with non-convergence angle nozzles exhibiting longer concentrated distribution periods than convergence angle *** nozzle convergence angles lead to increased penetration distance,frontal velocity,and radial diffusion distance during the initial stages of jet ***,stable jet shapes show larger divergence angles as nozzle convergence angle decreases,with the largest divergence angle observed atα=60°.In the initial 0-7 ms of jet development,the powder fuel jet demonstrates greater penetration distance and frontal velocity under certain ***,penetration distance and frontal velocity increase with throat length from 7 to 20 ms,accompanied by changes in divergence ***,at a throat length(l)of 2 mm,the near-field divergence angle measures 46.50°,and the far-field divergence angle is 22.25°.Conversely,at l=8mm,the near-field divergence angle is 33.49°,and the far-field divergence angle is 23.21°.The fluidization gas composition minimally affects jet penetration distance and frontal velocity during the initial 0-3 ***,due to hydrogen's low density,hydrogen/powder fuel jets exhibit shorter distances and velocities compared to nitrogen/powder fuel *** fluidization also results in larger divergence angles,particularly in the near *** findings underscore the importance of nozzle design and fluidization gas composition in optimizing scramjet performance and efficiency.

关键词： Multiphase flows Gas-particle two-phase jet Nozzle contraction angle Powder fuel scramjet

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Absolute pose estimation of UAV based on large-scale satellite image

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Chinese Journal of Aeronautics 2024年第6期37卷 219-231页

作者： hanyu WANG Qiang SHEN Zilong DENG Xinyi CAO Xiaokang Wang School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Obtaining absolute pose based on pre-loaded satellite images is one of the important means of autonomous navigation for small Unmanned Aerial Vehicles(UAVs)in Global Navigation Satellite System(GNSS)denied *** of the previous works have tended to build Convolutional Neural Networks(CNNs)to extract features and then directly regress the pose,which will fail when solving the challenges caused by the huge viewpoint and size differences between“UAV-satellite”image pairs in real-world ***,this paper proposes a probability distribution/regression integrated deep model with the attention-guided triple fusion mechanism,which estimates discrete distributions in pose space and three-dimensional vectors in translation *** order to overcome the shortage of the relevant dataset,this paper simulates image datasets captured by UAVs with forward-facing cameras during target searching and autonomous *** effectiveness,superiority,and robustness of the proposed method are verified by simulated datasets and flight tests.

关键词： Satellite imagery Unmanned Aerial Vehicle(UAV) Deep neural networks Vision navigation von Mises-Fisher distribution

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Low-Frequency Stability Analysis of Power Electronic Traction Transformer Based Train-Network System

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1608-1617页

作者： Yi Hong Yang Li Zhikang Shuai hanyu Yang College of Electrical and Information Engineering Hunan University and the Advanced Energy Technology Center of State Grid Shanghai Energy Interconnection Research Institute Co.Ltd.Shanghai 201203China College of Electrical and Information Engineering Hunan UniversityChangsha 410082China College of Electrical Engineering and Controal Science in Nanjing Tech University Nanjing 211816China

Power electronic traction transformers(PETTs)will be increasingly applied to locomotives in the future for their small volume and light ***,similar to conventional trains,PETTs behave as constant power loads and may cause low-frequency oscillation(LFO)to the train-network *** solve this issue,a mathematical model of the PETT is firstly proposed and verified based on the extended describing function(EDF)method in this *** the proposed model,the LLC converter is simplified to an equivalent circuit consisting of a capacitor and a resistor in *** is further demonstrated that the model can apply to various LLC converters with different topologies and ***,when the parameter differences between cells are not obvious,the PETT can be simplified to a single-phase rectifier(i.e.,conventional train)by equivalent *** on the model of PETT,the system low-frequency stability and influential factors are analyzed by using the generalized Nyquist ***,the correctness and accuracy of theoretical analyses are validated by off-line and hardware-in-the-loop simulation results.

关键词： Extended describing function method impedance model low-frequency oscillation power electronic traction transformer train-network system

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Universal insertion of molecules in ionic compounds under pressure

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National Science Review 2024年第1期11卷 120-128页

作者： Feng Peng Yanming Ma Chris J.Pickard hanyu Liu Maosheng Miao College of Physics and Electronic Information Luoyang Normal University Department of Chemistry and Biochemistry California State University Northridge State Key Laboratory of Superhard Materials & Key Laboratory of Material Simulation Methods and Software of Ministry of Education College of Physics Jilin University International Center of Future Science Jilin University Department of Materials Science & Metallurgy University of Cambridge Advanced Institute for Materials Research Tohoku University Department of Earth Science University of California Santa Barbara

Using first-principles calculations and crystal structure search methods, we found that many covalently bonded molecules such as H2, N2, CO2, NH3, H2O and CH4may react with NaC l, a prototype ionic solid,and form stable compounds under pressure while retaining their molecular structure. These molecules,despite whether they are homonuclear or heteronuclear, polar or non-polar, small or large, do not show strong chemical interactions with surrounding Na and Cl ions. In contrast, the most stable molecule among all examples, N2, is found to transform into cyclo-N5-anions while reacting with NaC l under high pressures. It provides a new route to synthesize pentazolates, which are promising green energy materials with high energy density. Our work demonstrates a unique and universal hybridization propensity of covalently bonded molecules and solid compounds under pressure. This surprising miscibility suggests possible mixing regions between the molecular and rock layers in the interiors of large planets.

关键词： molecule-solid hybrid materials high-pressure crystal structure prediction density functional theory planet interior

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An Empirical Study on the Effectiveness of Adversarial Examples in Malware Detection

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3535-3563页

作者： Younghoon ban Myeonghyun Kim Haehyun Cho School of Software Soongsil UniversitySeoul06978Korea

Antivirus vendors and the research community employ Machine Learning(ML)or Deep Learning(DL)-based static analysis techniques for efficient identification of new threats,given the continual emergence of novel malware *** the other hand,numerous researchers have reported that Adversarial Examples(AEs),generated by manipulating previously detected malware,can successfully evade ML/DL-based *** antivirus systems,in particular,have been identified as vulnerable to such *** paper firstly focuses on conducting black-box attacks to circumvent ML/DL-based malware *** attack method utilizes seven different perturbations,including Overlay Append,Section Append,and Break Checksum,capitalizing on the ambiguities present in the PE format,as previously employed in evasion attack *** directly applying the perturbation techniques to PE binaries,our attack method eliminates the need to grapple with the problem-feature space dilemma,a persistent challenge in many evasion attack *** a black-box attack,our method can generate AEs that successfully evade both DL-based and ML-based ***,AEs generated by the attack method retain their executability and malicious behavior,eliminating the need for functionality *** thorogh evaluations,we confirmed that the attack method achieves an evasion rate of 65.6%against well-known ML-based malware detectors and can reach a remarkable 99%evasion rate against well-known DL-based malware ***,our AEs demonstrated the capability to bypass detection by 17%of vendors out of the 64 on VirusTotal(VT).In addition,we propose a defensive approach that utilizes Trend Locality Sensitive Hashing(TLSH)to construct a similarity-based defense *** several experiments on the approach,we verified that our defense model can effectively counter AEs generated by the perturbation *** conclusion,our defense model alleviates the limitation of the mos

关键词： Malware classification machine learning adversarial examples evasion attack cybersecurity

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