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GS-orthogonalization OMP method for space target detection via bistatic space-based radar

Chinese Journal of Aeronautics 2024年第7期37卷 333-351页

作者： Shuyu ZHENG Libing JIANG Qingwei YANG Yingjian ZHAO Zhuang WANG National Key Laboratory of Science and Technology on Automatic Target Recognition College of Electronic Science and TechnologyNational University of Defense TechnologyChangsha 410073China

A space-based bistatic radar system composed of two space-based radars as the transmitter and the receiver respectively has a wider surveillance region and a better early warning capability for high-speed targets,and it can detect focused space targets more flexibly than the monostatic radar system or the ground-based radar ***,the target echo signal is more difficult to process due to the high-speed motion of both space-based radars and space *** be specific,it will encounter the problems of Range Cell Migration(RCM)and Doppler Frequency Migration(DFM),which degrade the long-time coherent integration performance for target detection and localization *** solve this problem,a novel target detection method based on an improved Gram Schmidt(GS)-orthogonalization Orthogonal Matching Pursuit(OMP)algorithm is proposed in this ***,the echo model for bistatic space-based radar is constructed and the conditions for RCM and DFM are ***,the proposed GS-orthogonalization OMP method is applied to estimate the equivalent motion parameters of space ***,the RCM and DFM are corrected by the compensation function correlated with the estimated motion ***,coherent integration can be achieved by performing the Fast Fourier Transform(FFT)operation along the slow time direction on compensated echo *** simulations and real raw data results validate that the proposed GS-orthogonalization OMP algorithm achieves better motion parameter estimation performance and higher detection probability for space targets detection.

关键词： Bistatic space-based radar High-speed maneuvering space targets detection Range Cell Migration(RCM) Doppler Frequency Migration(DFM) Gram Schmidt(GS)-orthogonalization Orthogonal Matching Pursuit(OMP)algorithm

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GTE: learning code AST representation efficiently and effectively

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science China(Information sciences) 2025年第3期68卷 393-394页

作者： Yihao QIN Shangwen WANG Bo LIN Kang YANG Xiaoguang MAO College of Computer Science and Technology National University of Defense Technology Key Laboratory of Software Engineering for Complex Systems National University of Defense Technology

With the development of deep learning in recent years, code representation learning techniques have become the foundation of many software engineering tasks such as program classification [1] and defect detection. Earlier approaches treat the code as token sequences and use CNN, RNN, and the Transformer models to learn code representations.

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Optically levitated micro gyroscopes with an MHz rotational vaterite rotor

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Microsystems & Nanoengineering 2024年第3期10卷 219-227页

作者： Kai Zeng Xiangming Xu Yulie Wu Xuezhong Wu Dingbang Xiao College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China College of Information and Communication National University of Defense TechnologyWuhan 430000China Key Laboratory of Satellite Navigation Technology National University of Defense TechnologyChangsha 410073China

The field of levitated optomechanics has experienced significant advancements in manipulating the translational and rotational dynamics of optically levitated particles and exploring their sensing *** concept of using optically levitated particles as gyroscopes to measure angular motion has long been explored but has not yet been proven either theoretically or *** this study,we present the first rotor gyroscope based on optically levitated high-speed rotating *** gyroscope is composed of a micrometer-size ellipsoidal vaterite particle that is driven to rotate at MHz frequencies in a vacuum *** an external angular velocity is input,the optical axis deviates from its initial position,resulting in changes in the frequency and amplitude of the rotational *** analyzing these changes,the angular velocity of the input can be accurately detected,making it the smallest rotor gyroscope in the *** angular rate bias instability of the gyroscope is measured to be 0.08°/s and can be further improved to as low as 10^(−9)°/h theoretically by cooling the motion and increasing the angular moment of the levitated *** work opens a new application paradigm for levitated optomechanical systems and may pave the way for the development of quantum rotor gyroscopes.

关键词： particles rotational angular

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Lightweight multifunctional metamaterial with low-frequency vibroacoustic reduction and load-bearing performances

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Applied Mathematics and Mechanics(English Edition) 2025年第3期46卷 403-422页

作者： Qi JIA Dianlong YU Donghai HAN Jihong WEN National Key Laboratory of Equipment State Sensing and Smart Support College of Intelligence Science and TechnologyNational University of Defense TechnologyChangsha 410073China

Metamaterials can control and manipulate acoustic/elastic waves on a subwavelength scale using cavities or additional ***,the large cavity and weak stiffness components of traditional metamaterials may cause a conflict between vibroacoustic reduction and load-bearing capacity,and thus limit their ***,we propose a lightweight multifunctional metamaterial that can simultaneously achieve low-frequency sound insulation,broadband vibration reduction,and excellent load-bearing performance,named as vibroacoustic isolation and bearing metamaterial(VIBM).The advent of additive manufacturing technology provides a convenient and reliable method for the fabrication of VIBM *** results show that the compressive strength of the VIBM is as high as 9.71 MPa,which is nearly 87.81%higher than that of the conventional grid structure(CGS)under the same volume ***,the vibration and sound transmission are significantly reduced over a low and wide frequency range,which agrees well with the experimental data,and the reduction degree is obviously larger than that obtained by the *** design strategy can effectively realize the key components of metamaterials and improve their application scenarios.

关键词： multifunctional metamaterial low-frequency sound insulation broadband vibration reduction load bearing

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The quantum Ising model for perfect matching and solving it with variational quantum eigensolver

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science China(Information sciences) 2024年第9期67卷 306-320页

作者： Qilin ZHENG Pingyu ZHU Chao WU Miaomiao YU Weihong LUO Ping XU Institute for Quantum Information and State Key Laboratory of High Performance Computing College of Computer Science and Technology National University of Defense Technology Hefei National Laboratory

Obtaining all perfect matchings of a graph is a tough problem in graph theory, and its complexity belongs to the #P-Complete class. The problem is closely related to combinatorics, marriage matching problems, dense subgraphs, the Gaussian boson sampling, chemical molecular structures, and dimer *** this paper, we propose a quadratic unconstrained binary optimization formula of the perfect matching problem and translate it into the quantum Ising model. We can obtain all perfect matchings by mapping them to the ground state of the quantum Ising Hamiltonian and solving it with the variational quantum eigensolver. Adjusting the model's parameters can also achieve the maximum or minimum weighted perfect matching. The experimental results on a superconducting quantum computer of the Origin Quantum Computing technology Company show that our model can encode 2~n dimensional optimization space with only O（n） qubits consumption and achieve a high success probability of the ground state corresponding to all perfect matchings. In addition, the further simulation results show that the model can support a scale of more than 14 qubits, effectively resist the adverse effects of noise, and obtain a high success probability at a shallow variational depth. This method can be extended to other combinatorial optimization problems.

关键词： perfect matching Ising model quantum Hamiltonian variational quantum eigensolver quadratic unconstrained binary optimization

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Evaluation and Suppression of Vibrational Noise for Cryogenic Surface Electrode Ion Traps

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Chinese Physics Letters 2025年第3期42卷 52-62页

作者： Qingqing Qin Baoquan Ou Wei Wu Yi Xie Ting Chen Chunwang Wu Pingxing Chen Institute for Quantum Science and Technology College of ScienceNational University of Defense TechnologyChangsha 410073China Hunan Key Laboratory of Mechanism and Technology of Quantum Information Changsha 410073China Department of Physics College of ScienceNational University of Defense TechnologyChangsha 410073China

Cryogenic ion traps offer substantial advantages over their room-temperature counterparts,particularly in terms of stable ion confinement and ***,this technological advancement has introduced a significant challenge,namely the generation of additional vibrational *** noise is pronounced during the compression and expansion phases of the Gifford–McMahon cycle refrigerator and stems from the mechanical operation of the cold *** residual vibrational noise can modulate the Rabi oscillation frequency,thereby compromising the fidelity of the quantum logic *** this study,we quantitatively assess the impact of residual vibrational noise and introduce an innovative strategy for its *** strategy was designed to reduce superimposed potential fluctuations within a cryogenic surface electrode ion *** measured residual vibrational noise was used for real-time feedback *** the inverse determination of the compensating potential for a stable superimposed trapping potential is an inherently ill-posed problem considering known measurement noise *** applying quadratic programming,we numerically calculated the optimal time series for the compensation *** ensemble of these compensation voltages was applied in real time to the static compensation *** this method is in the theoretical stage,we believe that it can effectively suppress the translation induced by vibrational noise and foster the creation of a stable superimposed harmonic *** deployment of this technique is expected to substantially improve the accuracy of quantum operations,thereby fueling the evolution of quantum technologies.

关键词： vibrational thereby quantum

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A guidance and control design with reduced information for a dual-spin stabilized projectile

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Defence technology（防务技术） 2024年第3期33卷 494-505页

作者： Yu Wang Jiyan Yu Xiaoming Wang Jia Fangxiu Intelligent Ammunition Technology National Defense Key Discipline Laboratory Nanjing University of Science and TechnologyNanjingJiangsu210094China

In this paper,an integrated guidance and control method based on an adaptive path-following controller is proposed to control a spin-stabilized projectile with only translational motion information under the constraint of an actuator,uncertainties in aerodynamic parameters and measurements,and control system *** to the fairly high rotation speed,the dynamic model of this missile is strongly nonlinear,uncertain and coupled in pitch,yaw and roll channels.A theoretical equivalent resultant force and uncertainty compensation method are comprehensively used to realize decoupling of pitch and *** response to the strong nonlinear and time-varying characteristics of the dynamic system,the quasi-linear model whose parameters are obtained by interpolation of points selected as the segmentation points in the trajectory envelope,is used for calculation in each *** cope with the system uncertainty caused by model approximation,parameter uncertainty and ballistic interference,an extended state estimator is used to compensate the output feedback according to the test ballistic *** order to improve the tracking efficiency and ensure the tracking error convergence with only translational motion information,the virtual guide point,whose derivative is deduced according to the Lyapunov principle,is calculated in real time according to the projection relationship between the real-time position and the reference trajectory,and a virtual line-of-sight angle and the backstepping method are used for the design of the guidance and control *** order to avoid the influence of control input saturation on the guidance and control performance due to the actuator limitation and improve the robustness of the system,an anti-saturation compensator is designed according to the two-step *** feasibility and effectiveness of the path-following controller is verified through closed-loop flight simulations with measurement,control,and condition *** result

关键词： Spin-stabilized projectile Reduced information Path-following control Extended state observer Coupled nonlinear system Input saturation

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Mission-oriented capability evaluation for combat network based on operation loops

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Defence technology（防务技术） 2024年第12期42卷 156-175页

作者： Yang Wang Junyong Tao Xiaoke Zhang Guanghan Bai Yunan Zhang Laboratory of Science and Technology on Integrated Logistics Support College of Intelligence Science and TechnologyNational University of Defense TechnologyChangsha 410073China National Key Laboratory for Complex Systems Simulation Beijing 100101China

With continuous growth in scale,topology complexity,mission phases,and mission diversity,challenges have been placed for efficient capability evaluation of modern combat *** at the problems of insufficient mission consideration and single evaluation dimension in the existing evaluation approaches,this study proposes a mission-oriented capability evaluation method for combat systems based on operation ***,a combat network model is given that takes into account the capability properties of combat ***,based on the transition matrix between combat nodes,an efficient algorithm for operation loop identification is proposed based on the Breadth-First *** the mission-capability satisfaction of nodes,the effectiveness evaluation indexes for operation loops and combat network are proposed,followed by node importance *** a case study of the combat scenario involving space-based support against surface ships under different strategies,the effectiveness of the proposed method is *** results indicated that the ROI-priority attack method has a notable impact on reducing the overall efficiency of the network,whereas the O-L betweenness-priority attack is more effective in obstructing the successful execution of enemy attack missions.

关键词： Combat network Operation loop identification Mission-oriented Network reliability Network effectiveness evaluation Strike strategies

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Tunable quantum dots in monolithic Fabry-Perot microcavities for high-performance single-photon sources

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Light(science & Applications) 2024年第2期13卷 325-332页

作者： Jiawei Yang Yan Chen Zhixuan Rao Ziyang Zheng Changkun Song Yujie Chen Kaili Xiong Pingxing Chen Chaofan Zhang Wei Wu Ying Yu Siyuan Yu State Key Laboratory of Optoelectronic Materials and Technologies School of Electronics and Information TechnologySun Yat-Sen UniversityGuangzhou 510006China Institute for Quantum Science and Technology College of ScienceNational University of Defense TechnologyChangsha 410073China College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China Hunan Key Laboratory of Quantum Information Mechanism and Technology National University of Defense TechnologyChangsha 410073 HunanChina Hefei National Laboratory Hefei 230088China

Cavity-enhanced single quantum dots(QDs)are the main approach towards ultra-high-performance solid-state quantum light sources for scalable photonic quantum ***,harnessing the Purcell effect requires precise spectral and spatial alignment of the QDs’emission with the cavity mode,which is challenging for most *** we have successfully integrated miniaturized Fabry-Perot microcavities with a piezoelectric actuator,and demonstrated a bright single-photon source derived from a deterministically coupled QD within this *** the cavity-membrane structures,we have achieved large spectral tunability via strain *** resonance,a high Purcell factor of~9 is *** source delivers single photons with simultaneous high extraction efficiency of 0.58,high purity of 0.956(2)and high indistinguishability of 0.922(4).Together with its compact footprint,our scheme facilitates the scalable integration of indistinguishable quantum light sources on-chip,therefore removing a major barrier to the development of solid-state quantum information platforms based on QDs.

关键词： quantum removing purity

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Ultra-low power MoS2 optoelectronic synapse with wavelength sensitivity for color target recognition

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science China(Information sciences) 2025年第4期68卷 187-196页

作者： Bo WEI Yabo CHEN Xiaotong HAN Yan KANG Bujia LIANG Cheng LI Xiaokuo YANG Liang FANG Yuanxi PENG Institute for Quantum Information & State Key Laboratory of High Performance Computing College of ComputerNational University of Defense Technology Fundamentals Department Air Force Engineering University College of Advanced Interdisciplinary Studies National University of Defense Technology Institute of Quantum Information Science and Technology College of ScienceNational University of Defense Technology College of Computer National University of Defense Technology

Optoelectronic synapses that integrate visual perception and pre-processing hold significant potential for neuromorphic vision systems（NVSs）. However, due to a lack of wavelength sensitivity, existing NVS mainly focuses on gray-scale image processing, making it challenging to recognize color images. Additionally, the high power consumption of optoelectronic synapses, compared to the 10 fJ energy consumption of biological synapses, limits their broader application. To address these challenges, an energy-efficient NVS capable of color target recognition in a noisy environment was developed,utilizing a MoS2optoelectronic synapse with wavelength sensitivity. Benefiting from the distinct photon capture capabilities of 450, 535, and 650 nm light, the optoelectronic synapse exhibits wavelength-dependent synaptic plasticity, including excitatory postsynaptic current（EPSC）, paired-pulse facilitation（PPF）, and long-term plasticity（LTP）. These properties can effectively mimic the visual memory and color discrimination functions of the human vision system. Results demonstrate that the NVS, based on MoS2optoelectronic synapses, can eliminate the color noise at the sensor level, increasing color image recognition accuracy from 50% to 90%. Importantly, the optoelectronic synapse operates at a low voltage spike of0.0005 V, consuming only 0.075 fJ per spike, surpassing the energy efficiency of both existing optoelectronic and biological synapses. This ultra-low power, color-sensitive device eliminates the need for color filters and offers great promise for future deployment in filter-free NVS.

关键词： optoelectronic synapse neuromorphic vision system color recognition 2D materials image pre-processing

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