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4th International Symposium on Plasma and Energy Convention, ISPEC 2022

作者： Li, Chen Feng, Juan Yuan, Wei Cao, Yuchen Han, Ruoyu School of Physics Beijing Institute of Technology Beijing100081 China State Key Laboratory of Mechatronics Engineering and Control Beijing Institute of Technology Beijing100081 China

ISBN: (纸本)9789819915750

Electrical explosion spraying, due to its high reaction temperature and intense mechanical effect, like strong shock wave and high-speed expanded explosive products, is a kind of satisfactory thermal spraying method. It had used to prepare single- or multi-element wire coating;however, the investigation of middle physical process was lacked, which was not beneficial to deeply understand the coating formation characteristics with the explosive process. In this study, a directional electrical explosion device was designed, which was available for synthesizing dense and homogeneous coating. Experiments were performed with intertwined Cu-Ni wire, and intertwined Cu-Ni-Al wire. Electrical and radiational diagnoses including current/voltage waveforms and self-emission images were used to investigate the explosive characteristics. SEM and XRD characterizations were used to study the morphology and crystallography of the produced coating. For intertwined two-wire (Cu-Ni) explosion, the parameters were measured separately to explore more details according to the corresponding dynamic high-speed images. The results indicated that the multi-wire explosion was non-synchronously with different explosive behaviors of wires;therefore, the discharge product channel showed a mixture of plasma, un-ionized metal vapor, and un-vaporized metal drops. Accordingly, the sprayed coating was composed by μm-scaled chunks or plates with some nanoparticles adhering on them. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Nanoparticles

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Cooperative decision-making algorithm with efficient convergence for UCAV formation in beyond-visual-range air combat based on multi-agent reinforcement learning

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Chinese Journal of Aeronautics 2024年第8期37卷 311-328页

作者： Yaoming ZHOU Fan YANG Chaoyue ZHANG Shida LI Yongchao WANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of Industrial Control Technology Institute of Cyber-Systems and ControlZhejiang UniversityHangzhou 310027China

Highly intelligent Unmanned Combat Aerial Vehicle(UCAV)formation is expected to bring out strengths in Beyond-Visual-Range(BVR)air *** Multi-Agent Reinforcement Learning(MARL)shows outstanding performance in cooperative decision-making,it is challenging for existing MARL algorithms to quickly converge to an optimal strategy for UCAV formation in BVR air combat where confrontation is complicated and reward is extremely sparse and *** to solve this problem,this paper proposes an Advantage Highlight Multi-Agent Proximal Policy Optimization(AHMAPPO)***,at every step,the AHMAPPO records the degree to which the best formation exceeds the average of formations in parallel environments and carries out additional advantage sampling according to ***,the sampling result is introduced into the updating process of the actor network to improve its optimization ***,the simulation results reveal that compared with some state-of-the-art MARL algorithms,the AHMAPPO can obtain a more excellent strategy utilizing fewer sample episodes in the UCAV formation BVR air combat simulation environment built in this paper,which can reflect the critical features of BVR air *** AHMAPPO can significantly increase the convergence efficiency of the strategy for UCAV formation in BVR air combat,with a maximum increase of 81.5%relative to other algorithms.

关键词： Unmanned combat aerial vehicle(UCAV)formation Decision-making Beyond-visual-range(BVR)air combat Advantage highlight Multi-agent reinforcement learning(MARL)

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Aerosol-radiation interaction and its variation in North China within 2015–2019 period under continuous PM_(2.5)improvements

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Journal of Environmental Sciences 2024年第2期136卷 81-94页

作者： Zhe Lv Xiaoqi Wang Wei Wei Huahua Bai Xiaoyu Liu Guohao Li Shuiyuan Cheng Department of Environmental Science and Engineering Beijing University of TechnologyBeijing 100124China Key Laboratory of Beijing on Regional Air Pollution Control Beijing 100124China Beijing Municipal Research Institute of Eco-Environmental Protection Beijing 100037China Beijing Key Laboratory of Urban Atmospheric Volatile Organic Compounds Pollution Control and Application Beijing 100037China

A study was conducted on aerosol-radiation interactions over six cities in this region within the 2015–2019 ***-Chem simulations on 2017 showed that based on the six-city average,the aerosol load(PM_(2.5)concentrations)of 121.9,49.6,43.3,and 66.3μg/m^(3)in January,April,July,and October,mainly lowered the level of downward shortwave radiation by 38.9,24.0,59.1,and 24.4 W/m~2and reduced the boundary layer height by 79.9,40.8,87.4,and 31.0 m,via scattering and absorbing solar *** sensitivity of meteorological changes to identical aerosol loads varied in the order July>January>October and ***,the cooling and stabilizing effects of aerosols further led to increases in PM_(2.5),by23.0,3.4,4.6,and 7.3μg/m^(3)respectively in the four *** sensitivity of the effect of aerosols on PM_(2.5)was greatest in January rather than in July,contrary to the effect on ***,a negative linear relation was observed between daily BLH reductions and aerosol loads in fall and winter,and between PM_(2.5)increases and aerosol loads in all *** the PM_(2.5)pollution improvements in this region,the aerosol radiative forcing was effectively *** should result in daily BLH increases of 10–24 m in fall and winter,and the estimates in beijing agreed well with the corresponding results based on AMDAR ***,the reduction in aerosol radiation effects brought about daily PM_(2.5)decreases of 1.6-2.8μg/m^(3),accounting for 7.0%–17.7%in PM_(2.5)improvements.

关键词： Radiative forcing Aerosol PM_(2.5) Boundary layer height(BLH) North China

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Surrogate-assisted optimization for anti-ship missile body configuration considering high-velocity water touching

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Chinese Journal of Aeronautics 2023年第12期36卷 268-281页

作者： Nianhui YE Teng LONG Junhui MENG Renhe SHI Baoshou ZHANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of EducationBeijing 100081China

As a crucial weapon in the sea battle,anti-ship missiles generally employ a sea-skimming penetration strategy to reduce the probability of being detected by the target radar,which greatly increases the risk of touching water caused by sensor errors or random sea *** alleviate the large impact load by high-velocity water touching,a novel anti-ship missile body configuration is proposed in this paper,which is inspired by the idea of hydroplaning.A parametric geometry model is first developed to modify the configuration of the anti-ship missile ***,a structured arbitrary Lagrange-Eulerian based Fluid-Structure Interaction(FSI)model is established to analyze the kinematics parameters of the missile body during the hydroplaning process.A missile body configuration optimization problem is then formulated to minimize the impact load considering several constraints,e.g.,horizontal velocity loss,pitch angle after touching water,and inside capacity for *** to the time-consuming FSI simulation,a Kriging-assisted constrained differential evolution method is utilized to optimize the missile body configuration for reducing the impact *** the optimization process,radial basis function and Kriging are combined with evolutionary operators to lead the search to the vicinity of the optimum *** result shows that the proposed missile body configuration can reduce the impact load by 18.8%compared with the ordinary ***,the optimized configuration can further yield a 17.4%impact load decrease subject to all the constraints and avoid structural damage by the high-velocity water touching,which demonstrates the effectiveness and practicability of the proposed anti-ship missile body configuration and corresponding optimization framework for reducing the impact load.

关键词： Surrogate-assisted optimiza-tion Fluid-structureinteraction Arbitrary Lagrange-Eulerian Missile Conceptual design

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IEEE Transactions on Aerospace and Electronic Systems 2025年第3期61卷 7597-7609页

作者： Wu, Wenjing Fu, Hanjing Cui, Kaixin Liu, Zhigang Yang, Dong Shi, Dawei Beijing Institute of Technology MIIT Key Laboratory of Servo Motion System Drive and Control School of Automation Beijing100081 China Beijing Institute of Spacecraft System Engineering Beijing100094 China

Data limitation caused by the difficulty of data acquisition, the high cost of data collection, and the changes of working conditions is a serious obstacle to the accurate lithium-ion battery SOH estimation for spacecrafts system. To achieve accurate few-shot lithium-ion battery state of health(SOH) estimation and enhance the adaptability of learning methods across varying working conditions, a domain similarity model agnostic meta-learning method (DS-MAML) is proposed. First, we design a dynamic-static feature extraction method to adequately exploit information from the limited battery data and link the obtained features by gray correlation coefficients to collect sufficient information. Then, by calculating the domain similarity between the training tasks through the maximum mean discrepancy algorithm, the training tasks are ranked to reduce the re-training time. Finally, an LSTM model is added to the meta-learning framework to capture the long-term dependency relationships between SOH and time series of the voltage, and the ranked tasks are embedded in the meta-training process to improve adaptability in different working conditions. The effectiveness of the proposed method is validated by NASA and MIT datasets, and comparative experimental results illustrate that the proposed method average error is reduced by 73%, and the running speed is increased by 20% compared with traditional MAML in few-shot scenarios. © 1965-2011 IEEE.

关键词： state of charge

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Dynamic damage characteristics and control mechanism of rocks anchored by constant resistance and energy absorption material

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International Journal of Mining Science and technology 2025年第1期35卷 57-67页

作者： Bei Jiang Kunbo Wu Qi Wang Yetai Wang Wenrui Wu Yaoxia Feng Yanbo Zhang State Key Laboratory for Tunnel Engineering China University of Mining&Technology-BeijingBeijing 100083China State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of TechnologyBeijing 100081China Collaborative Innovation Center of Green Development and Ecological Restoration of Mineral Resources North China University of Science and TechnologyTangshan 063210China

With resource exploitation and engineering construction gradually going deeper,the surrounding rock dynamic disaster becomes frequent and *** anchorage support is a common control method of surrounding rock in underground *** study the dynamic damage characteristics of anchored rock and the energy absorption control mechanism of dynamic disasters,a new type of constant resistance and energy absorption(CREA)material with high strength,high elongation and high energy absorption characteristics is developed.A contrast test of rockbursts in anchored rock with different support materials is *** test results show that the surface damage rates and energy release degree of anchored rock with common bolt(CB)and CREA are lower than those of unanchored rock,*** total energy,average energy and maximum energy released by CREA anchored rock are 30.9%,94.3%and 84.4%lower than those of CB anchored *** with unanchored rock,the rockburst peak stress in the CREA anchored rock is increased by 39.9%,and the rockburst time is delayed by 53.2%.Based on the rockburst energy calculation model,the evolution law of rockburst peak stress and energy release is *** control mechanism of CREA support units on rock dynamic failure is clarified.

关键词： Constant resistance and energy absorption Anchored rock Rockburst Peak stress control mechanism

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Targets capture by distributed active swarms via bio-inspired reinforcement learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 206-217页

作者： Kun Xu Yue Li Jun Sun Shuyuan Du Xinpeng Di Yuguang Yang Bo Li Institute of Biomechanics and Medical Engineering Applied Mechanics LaboratoryDepartment of Engineering MechanicsTsinghua UniversityBeijing 100084China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Shanghai Aerospace Control Technology Institute Shanghai 201109China Shanghai Key Laboratory of Aerospace Intelligent Control Technology Shanghai 201109China College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Natural swarms arranged from cells to herds are usually decentralized but display intriguing collective intelligence in coordinating individuals across large scales to efficiently achieve their common *** from nature may provide new strategies for controlling collective dynamics of synthetic swarms to accomplish specific ***,we present a bioinspired computational framework that steers distributed active swarms to collectively capture and merge targets via reinforcement *** exploit collective milling structures of natural herds to cage the targets,and adopt a switching control policy inspired by sperms’chiral dynamics to optimize the trajectories of individuals,through which the active swarms can selforganize to enclose single or multiple distant targets in a dynamical,adaptive and scalable *** exists a critical swarm size,beyond which the excessive competition between agents would generate large mechanical forces,leading to capture instability but enabling the transition from short-distance to long-distance merging capture of multiple *** work provides physical insights into distributed active swarms and could offer a multilevel,decentralized strategy toward controlling swarm robotics in wide applications such as bio-medical devices,machine immunity,and target clearance.

关键词： swarm intelligence robotics multi-tasks artificial intelligence bionics

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A review of motion planning for redundant space manipulators

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Science China(Technological Sciences) 2025年第3期68卷 30-53页

作者： Ziqiang ZHANG Xiaoshuo LIU Meng NING Xiaohui LI Weihui LIU Ye LU College of Mechanical and Energy Engineering Beijing University of TechnologyBeijing100124China School of Mechanical Engineering Jiangnan UniversityWuxi214122China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of Control EngineeringBeijing100094China Department of Civil Engineering Monash UniversityMelbourne3800Australia

Redundant space manipulators(RSM)exhibit high flexibility and can assist astronauts in completing various onorbit service(OOS)tasks,which have been applied to the International Space Station(ISS)and China Space Station(CSS).Motion planning stands as a fundamental technology within RSM,guiding the manipulator to reach designated positions smoothly and execute operational tasks with optimal ***,the intricate nature of the space environment presents challenges to the motion planning of *** this paper,in response to issues such as maintenance difficulties after RSM failures,base floating caused by weightlessness,flexible deformation of structures due to large-scale operations,and multiple obstacles with uncertainty,fault-tolerant motion planning,motion planning considering base floating,motion planning under structural flexibility deformation,and obstacle avoidance motion planning are *** present,the increasingly complex OOS tasks have brought new challenges to the motion planning of *** challenges encompass motion planning for new mechanism configurations,dynamic motion planning,multi-RSM and multi-task planning,the improvement of motion planning efficiency,and the efficient implementation and precise process monitoring of *** the advancement of motion planning technology,RSM is poised to play an increasingly significant role in ISS and CSS.

关键词： redundant space manipulator on-orbit service motion planning main challenges

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OH regulator of highly dispersed Ru sites on host Pd nanocrystals for selective ethanol electro-oxidation

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Nano Research 2024年第5期17卷 3863-3871页

作者： Zhihe Xiao Yueguang Chen Renjie Wu Yuwei He Chunfeng Shi Leyu Wang State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Research Institute of Petroleum Processing SINOPECBeijing 100083China

The ethanol oxidation reaction(EOR)is crucial in direct alcohol fuel cells and chemical ***,the electro-oxidation of ethanol molecules to produce acetaldehyde and carbon monoxide can poison the active sites of nanocatalysts,resulting in reduced performance and posing challenges in achieving high activity and selectivity for ethanol *** this study,we employed a dynamic seed-mediated method to precisely modify highly dispersed Ru sites onto well-defined Pd *** oxyphilic Ru sites serve as"OH valves",regulating water dissociation,while the surrounding Pd atomic arrangements control electronic states for the oxidation dehydrogenation of carbonaceous ***,Ru0.040@Pd nanocubes(Ru:Pd=0.04 at.%),featuring(100)facets in Ru-Pd4 configurations,demonstrate an outstanding mass activity of 6.53 A·mgPd^(-1) in EOR under alkaline conditions,which is 6.05 times higher than that of the commercial Pd/C catalyst(1.08 A·mgPd-1).Through in-situ experiments and theoretical investigations,we elucidate that the hydrophilic Ru atoms significantly promote the dynamic evolution of H_(2)O dissociation into OHads species,while the electron redistribution from Ru to adjacent Pd concurrently adjusts the selective oxidation of C_(2) *** host-guest interaction accelerates the subsequent oxidation of carbonaceous intermediates(CH_(3)CO_(ads))to acetate,while preventing the formation of toxic*CHx and*CO species,which constitutes the rate-determining step.

关键词： OH regulator atomic sites ethanol electro-oxidation host-guest interaction

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On the optimality of uniform velocity-deceleration separation scheme for tethered satellite systems

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control Theory and technology 2024年第4期22卷 503-516页

作者： Peng Yu Ji-Feng Zhang Shuping Tan Jin Guo Yanlong Zhao School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of Knowledge Automation for Industrial Processes Ministry of EducationBeijing100083China Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing100190China Beijing Institute of Control Engineering Beijing100094China

For mitigating the libration angle fluctuation of the tethered satellite system,this paper discusses how to make the uniform velocity-deceleration separation scheme achieve the best ***,a judgment condition is established to determine the tether state by comparing the tether length and the relative distance of the sub-satellite and the parent *** on the tethered satellite system dynamics equation and Clohessy-Wiltshire equation,dynamic models are given for four cases of tether ***,the influence of the uniform velocity-deceleration separation scheme on the libration angle is analyzed by taking the libration angle at the separation ending time and the mean absolute value of the libration angle as index ***,the optimality problem of the uniform velocity-deceleration separation scheme is formulated as an optimization problem with constraints,and an approximate solution algorithm is given by combining the back propagation neural network and Newton-Raphson method of multiple initial ***,the effectiveness of the proposed method is verified by a numerical simulation.

关键词： Tethered satellite systems Libration angle Uniform velocity-deceleration separation Neural network

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