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IEEE Journal on Miniaturization for Air and Space systems 2024年第2期6卷 1-1页

作者： Sun, Wentao Li, Zan Shi, Jia Bai, Zixuan Wang, Feng Quek, Tony Q. S. School of Telecommunications Engineering State Key Laboratory of Integrated ServiceNetworks Xidian University Xi’an China Information System Technology and Design Pillar University of Technology and Design Singapore

As an aerial base station (BS), unmanned aerial vehicle (UAV) has been considered as a promising platform to provide wireless data service in future networks due to its flexible, swift and low cost features. However, since the suddenness and randomness of ground users’ (GUs’) data requirements, it is challenging for the UAV BSs to dynamically make decisions to provide real-time data services to GUs. In a multi-mode UAV-assisted wireless network, we formulate a multi-objective optimization problem to minimize the average peak age of information (APAoI) and energy consumption of UAVs, and to maximize the accumulated service data (ASD) for GUs. Therefore, this paper proposes the multi-agent hybrid twin delayed deep deterministic policy gradient (MAHTDDDPG) algorithm with hybrid action space design, which is empowered by centralized training and distributed execution (CTDE) framework. In the proposed algorithm, the UAVs can cooperatively make decisions by sharing the GU status information, in a result of jointly optimizing the UAV trajectory, mode selection and transmit power. Simulation results demonstrate that our proposed approach achieves 79.6% and 120.4% higher reward than MADDPG algorithm and HTD-DDPG algorithm respectively. IEEE

关键词： Heuristic algorithms

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An anomaly detection method for spacecraft solar arrays based on the ILS-SVM model

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Journal of systems Engineering and Electronics 2023年第2期34卷 515-529页

作者： WANG Yu ZHANG Tao HUI Jianjiang LIU Yajie College of Systems Engineering National University of Defense TechnologyChangsha 410073China Hunan Key Laboratory of Multi-energy System Intelligent Interconnection Technology Changsha 410073China Beijing Institute of Tracking and Telecommunication Technology Beijing 100094China

Solar arrays are important and indispensable parts of spacecraft and provide energy support for spacecraft to operate in orbit and complete on-orbit *** a spacecraft is in orbit,because the solar array is exposed to the harsh space environment,with increasing working time,the performance of its internal electronic components gradually degrade until abnormal damage *** damage makes solar array power generation unable to fully meet the energy demand of a ***,timely and accurate detection of solar array anomalies is of great significance for the on-orbit operation and maintenance management of *** this paper,we propose an anomaly detection method for spacecraft solar arrays based on the integrated least squares support vector machine(ILS-SVM)model:it selects correlated telemetry data from spacecraft solar arrays to form a training set and extracts n groups of training subsets from this set,then gets n corresponding least squares support vector machine(LS-SVM)submodels by training on these training subsets,respectively;after that,the ILS-SVM model is obtained by integrating these submodels through a weighting operation to increase the prediction accuracy and so on;finally,based on the obtained ILS-SVM model,a parameterfree and unsupervised anomaly determination method is proposed to detect the health status of solar *** use the telemetry data set from a satellite in orbit to carry out experimental verification and find that the proposed method can diagnose solar array anomalies in time and can capture the signs before a solar array anomaly occurs,which reflects the applicability of the method.

关键词： spacecraft solar array anomaly detection integrated least squares support vector machine(ILS-SVM) induced ordered weighted average(IOWA)operator integrated model

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Coupling effects of SiC and TiB_(2) particles on crack inhibition in Al-Zn-Mg-Cu alloy produced by laser powder bed fusion

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Journal of Materials Science & technology 2023年第33期164卷 37-51页

作者： Ning Li Ting Wang Lixia Zhang Liang Zhang State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology at WeihaiWeihai 264209China Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology at WeihaiWeihai 264209China Institute of Intelligent Manufacturing Technology Shenzhen PolytechnicShenzhen 518055China

A novel Al-Zn-Mg-Cu alloy free of cracks was produced utilizing laser powder bed fusion(LPBF)and modified with SiC and TiB_(2) *** interdependent effects of SiC and TiB_(2) particles on morphology,microstructure,and crystallographic texture were *** mechanisms behind phase evolution and crack inhibition were *** results show that a nearly dense Al-Zn-Mg-Cu alloy could be obtained when the mass fraction of SiC and TiB2 particles was 4%.TiB_(2) particles remained stable and acted as nucleation agents in the molten *** SiC particles reacted with the Al matrix to form rod-like Al_(4)C_(3),lamellate Al_(4)SiC_(4),and flocculent Si phases,which provided nucleation agents and liquid replenishment for matrix *** columnar grains of the matrix were refined into equiaxed grains,and the average size decreased from 37.15μm to 7.54μ*** preferential growth of grains along the(001)〈001〉direction was suppressed and transformed into a disordered random *** innovative Al-Zn-Mg-Cu alloy demonstrated an ultimate tensile strength of 492±12 MPa and an elongation of 7.2%±0.7%.The microhardness was enhanced,and the microhardness heterogeneity was *** solidification properties were regulated,the temperature interval between solidus and liquidus was narrowed,and the liquidity of the molten pool was *** hot cracking of Al-Zn-Mg-Cu alloy was inhibited due to the interdependent effects of grain refinement by TiB2 particles and sufficient liquid metal replenishment by SiC particles.

关键词： Laser powder bed fusion Solidification cracks Al-Zn-Mg-Cu alloys In-situ reaction Microstructure evolution

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Review and prospects on the low-voltage Na_(2)Ti_(3)O_(7) anode materials for sodium-ion batteries

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Journal of Energy Chemistry 2024年第1期88卷 446-460,I0011页

作者： Jun Dong Yalong Jiang Ruxing Wang Qiulong Wei Qinyou An Xiaoxing Zhang Hubei Key Laboratory for High-efficiency Utilization of Solar Energy and Operation Control of Energy Storage System Hubei University of TechnologyWuhan 430068HubeiChina State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200HubeiChina Xiamen Key Laboratory of High-Performance Metals and Materials College of MaterialsXiamen UniversityXiamen 361005FujianChina State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070HubeiChina

Due to its low cost and natural abundance of sodium,Na-ion batteries(NIBs)are promising candidates for large-scale energy storage *** development of ultralow voltage anode materials is of great significance in improving the energy density of ***-voltage anode materials,however,are severely lacking in *** all the reported insertion oxides anodes,the Na_(2)Ti_(3)O_(7) has the lowest operating voltage(an average potential of 0.3 V ***^(+)/Na)and is less likely to deposit sodium,which has excellent potential for achieving NIBs with high energy densities and high *** significant progress has been made,achieving Na_(2)Ti_(3)O_(7) electrodes with excellent performance remains a severe *** paper systematically summarizes and discusses the physicochemical properties and synthesis methods of Na_(2)Ti_(3)O_(7).Then,the sodium storage mechanisms,key issues and challenges,and the optimization strategies for the electrochemical performance of Na_(2)Ti_(3)O_(7) are classified and further ***,remaining challenges and future research directions on the Na_(2)Ti_(3)O_(7) anode are *** review offers insights into the design of high-energy and high-safety NIBs.

关键词： Sodium-ion batteries Low-voltage anode materials Na_(2)Ti_(3)O_(7) Electrochemical performances Electrochemical mechanism

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Modeling and analysis of maneuver laws based on higher order multi-resolution dynamic mode decomposition for hypersonic glide vehicles

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Defence technology 2025年 48卷 34-47页

作者： Liu, Zichu Hu, Yudong Gao, Changsheng Jing, Wuxing Ji, Xudong School of Astronautics Harbin Institute of Technology Harbin150001 China State Key Laboratory of Micro-Spacecraft Rapid Design and Intelligent Cluster Harbin150001 China

The precise characterization of hypersonic glide vehicle (HGV) maneuver laws in complex flight scenarios still faces challenges. Non-stationary changes in flight state due to abrupt changes in maneuver modes place high demands on the accuracy of modeling methods. To address this issue, a novel maneuver laws modeling and analysis method based on higher order multi-resolution dynamic mode decomposition (HMDMD) is proposed in this work. A joint time-space-frequency decomposition of the vehicle's state sequence in the complex flight scenario is achieved with the higher order Koopman assumption and standard multi-resolution dynamic mode decomposition, and an approximate dynamic model is established. The maneuver laws can be reconstructed and analyzed with extracted multi-scale spatiotemporal modes with clear physical meaning. Based on the dynamic model of HGV, two flight scenarios are established with constant angle of attack and complex maneuver laws, respectively. Simulation results demonstrate that the maneuver laws obtained using the HMDMD method are highly consistent with those derived from the real dynamic model, the modeling accuracy is better than other common modeling methods, and the method has strong interpretability. © 2024 China Ordnance Society

关键词： Angle of attack

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Research progress of space non-pyrotechnic low-shock connection and separation technology(SNLT):A review

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Chinese Journal of Aeronautics 2022年第11期35卷 113-154页

作者： Honghao YUE Yifei YANG Yifan LU Fei YANG Jun WU Qi RUAN Zongquan DENG State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 15000lChina

Space missions have become diversified in recent years, where connection and separation devices play a crucial role as key components of various spacecraft. Traditional pyrotechnic devices have the advantages of large carrying capacity, rapid motion and functional reliability. However,their shortcomings such as great release shock, poor safety, unrepeatability and other prominent defects make them unsuitable for new generation spacecraft such as microsatellites to separate at low shock or lock repeatedly, etc. Therefore, it is necessary to develop space non-pyrotechnic low-shock connection and separation devices(SNLD) which are required for advanced aerospace missions. In this paper, the progress of the research on space non-pyrotechnic low-shock connection and separation technology(SNLT) is summarized and reviewed. Proceed from the principle of reducing shock for non-pyrotechnic devices, present studies are classified from the perspective of actuating technology and systematic designing methods. For non-pyrotechnic actuating techniques,according to different driving sources, the separation devices are classified into several main categories: electric, magnetic, gas and thermal actuating devices. The actuation principle and application prospect of separation techniques are introduced and the working process, dimension and mechanical properties of typical devices are compared and evaluated. For the systematic designing method, the common mechanism types of SNLDs are summarized according to the designing concept of reducing shock. Then connection configurations are classified according to the structural forms of connection devices, of which the principles, bearing capacities and general applications are discussed. This paper systematically summarizes the key problems, puts forward the future development trend of SNLT, and points out the breakthrough direction for related scholars.

关键词： Connection Low-shock Non-pyrotechnic Separation Space

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Failure evolution and disaster prediction of rock under uniaxial compression based on non-extensive statistical analysis of electric potential

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International Journal of Mining Science and technology 2024年第7期34卷 975-993页

作者： Tiancheng Shan Zhonghui Li Haishan Jia Enyuan Wang Xiaoran Wang Yue Niu Xin Zhang Dong Chen Shan Yin Quancong Zhang State Key Laboratory of Coal Mine Disaster Prevention and Control China University of Mining and TechnologyXuzhou 221116China National Engineering Research Center for Coal Gas Control China University of Mining and TechnologyXuzhou 221116China School of Safety Engineering China University of Mining and TechnologyXuzhou 221116China State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources China University of Mining and TechnologyXuzhou 221116China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China

Rock failure can cause serious geological disasters,and the non-extensive statistical features of electric potential(EP)are expected to provide valuable information for disaster *** this paper,the uniaxial compression experiments with EP monitoring were carried out on fine sandstone,marble and granite samples under four displacement *** Tsallis entropy q value of EPs is used to analyze the selforganization evolution of rock *** the influence of displacement rate and rock type on q value are explored by mineral structure and fracture modes.A self-organized critical prediction method with q value is *** results show that the probability density function(PDF)of EPs follows the q-Gaussian *** displacement rate is positively correlated with q *** the displacement rate increasing,the fracture mode changes,the damage degree intensifies,and the microcrack network becomes *** influence of rock type on q value is related to the burst intensity of energy release and the crack fracture *** q value of EPs can be used as an effective prediction index for rock failure like b value of acoustic emission(AE).The results provide useful reference and method for the monitoring and early warning of geological disasters.

关键词： Electric potential Non-extensive statistical feature Displacement rate q-Gaussian distribution Precursor prediction Rock materials

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Forming limit and failure behavior of fiber metal laminates under low-constraint conditions

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Chinese Journal of Aeronautics 2025年第1期38卷 638-653页

作者： Yao WANG Feng DING Yong LI Yunhua ZHANG Sifa ZHENG Libin ZHAO Ning HU School of Mechanical Engineering Hebei University of TechnologyTianjin 300401China Suzhou Automotive Research Institute(Xiangcheng) Tsinghua UniversitySuzhou 215134China State Key Laboratory of Reliability and Intelligence Electrical Equipment Hebei University of TechnologyTianjin 300130China School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Henan Benjie Technology Co. Ltd.Zhengzhou 450003China Key Laboratory of Advanced Intelligent Protective Equipment Technology Ministry of EducationTianjin 300401China Key Laboratory of Hebei Province on Scale-span Intelligent Equipment Technology Hebei University of TechnologyTianjin 300401China

Fiber Metal Laminates(FMLs),as high-performance composite materials,demonstrate exceptional potential in a wide range of applications,such as aeronautical and astronautical ***,the traditional cured FMLs possess complex interlayer stresses and low forming limits,restricting further promotion and application of ***-constraint FMLs exhibit a lower forming resistance and better formability due to no curing during the forming process;however,the formation mechanism and response are not *** paper presents the Forming Limit Diagram(FLD)of low-constraint GLARE(glass fiber reinforced aluminum laminates)based on the forming limit test,and compares it with the conventionally cured laminates to evaluate the differences in the forming *** addition,combined with the analysis of failure mechanism and micro-deformation mechanism of specimens,the influence of different temperatures(20–80℃)and forming states(width)on the deformation performance of laminates is further *** results reveal that the forming limit curve of low-constraint laminates shifts up with the increase of temperature,the forming limit initially increases with the increase of width,then followed by a gradual decrease,and the maximum principal strain of low-constraint laminates is increased by 29% at 80℃ compared to 20℃.The cured laminate has a principal strain range of 0–0.02,while the low-constraint laminates have a principal strain range of 0.03–*** with cured laminates,low-constraint laminates possess a higher forming limit due to the improvement in deformable degree between layers by resin flow and fiber slippage,which enhances their *** study is expected to serve as a reference for establishing forming limit criteria and optimizing forming schemes for low-constraint laminates.

关键词： Fiber Metal Laminates(FMLs) GLARE Low-constraint state Forming limit Failure mechanism

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Improved calibration and 3D reconstruction for micro fringe projection profilometry

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Optics Express 2025年第6期33卷 13455-13471页

作者： Zhang, Chenfan Zhu, Dongchen Shi, Wenjun Wang, Lei Li, Jiamao Bionic Vision System Laboratory State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai200050 China University of Chinese Academy of Sciences Beijing100049 China

Micro fringe projection profilometry (MFPP) is a crucial three-dimensional measurement technology widely used in industrial inspection. As the system measurement accuracy is limited by calibration and reconstruction errors, this paper proposes a joint calibration of telecentric camera and projector, and develops noise-robust 3D reconstruction, ultimately forming a high-precision MFPP for microscopic object measurement. Specifically, the optimal parameters for the telecentric camera model are determined by constructing a virtual 3D calibration target, which circumvents the limitations that plane-based calibration methods often produce local optimal solutions. In response to the presence of phase errors, a method employing global homography is proposed to refine the projector pixel coordinates of feature points, thus enhancing the calibration accuracy of the projector. Furthermore, we integrate epipolar constraints into the reconstruction process, which helps eliminate noise points and optimizes the reconstruction results by constructing epipolar deviation. Extensive experiments demonstrate that our MFPP system can achieve micron-level measurement accuracy. © 2025 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.

关键词： Profilometry

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Turbulent drag reduction by sector-shaped counter-flow dielectric barrier discharge plasma actuator

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Chinese Physics B 2025年第2期34卷 362-370页

作者： Borui Zheng Shaojie Qi Minghao Yu Jianbo Zhang Linwu Wang Dongliang Bian School of Automation and Information Engineering Xi’an University of TechnologyXi’an 710048China School of Mechanical and Precision Instrument Engineering Xi’an University of TechnologyXi’an 710048China Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi’an 710038China Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi’an 710048China Shaanxi University Key Laboratory of Photonic Power Devices and Discharge Regulation Xi’an 710048China

The primary objective in aircraft transportation is to minimize turbulent drag, thereby conserving energy and reducing emissions. We propose a sector-shaped counter-flow dielectric barrier discharge plasma actuator, which leverages jet synthesis for drag reduction. A drag control experiment was conducted in a low-speed wind tunnel with a controlled flow velocity of 9.6 m/s(Re = 1.445 × 10^(4)). This study investigated the effects of varying pulse frequencies and actuation voltages on the turbulent boundary layer. Using a hot-wire measurement system, we analyzed the pulsating and time-averaged velocity distributions within the boundary layer to evaluate the streamwise turbulent drag reduction. The results show that the local TDR decreases as the pulse frequency increases, reaching a maximum reduction of approximately 20.97% at a pulse frequency of 50 Hz. In addition, as the actuation voltage increases, the friction coefficient decreases, increasing the drag reduction rate. The maximum drag reduction of approximately 33.34% is achieved at an actuation voltage of 10 kV.

关键词： plasma flow control turbulent boundary layer turbulent drag reduction

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