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2024 Conference on Spectral technology and Applications, CSTA 2024

作者： Jian, Haopeng Xue, Shuai Huang, Yihang Wang, Linfeng College of Intelligence Science and Technology National University of Defense Technology Hunan Changsha410073 China Laboratory of Science and Technology on Integrated Logistics Support National University of Defense Technology Hunan Changsha410073 China Hunan Key Laboratory of Ultra-Precision Machining Technology Hunan Changsha410073 China State Key of High Performance Complex Manufacturing Central South University Hunan Changsha410073 China

ISBN: (纸本)9781510683082

As an adaptive optics that can modulate phase of lights, spatial light modulators (SLMs) are widely used in laser shaping, telescopes, and surface figure interferometric tests. The phase control accuracy of SLMs affects the performance of these optical systems. However, the traditional birefringence effects-based phase control method has relatively low accuracy due to the non-linear phase response of SLMs. To this end, a diffractive interferogram-based phase control method is proposed. The general model for describe the diffraction-based phase control method is established. The phase control error model of the diffractive interferogram-based phase control method is analyzed theoretically. Theoretical analysis was conducted to analyze the phase quantization and discretization that influence the phase accuracy. By applying the discretized interference pattern with appropriate quantization level of a given phase and a standard reference phase into the SLM, phase control accuracy can be enhanced up to about λ/30 (λ=632.8 nm) root-mean-square. Comparisons of phase control accuracy of the proposed method with the traditional phase control method are conducted to verify the accuracy enhancement. Using the proposed method, the SLMs can be applied in systems with collimated or divergent beams configuration that requires high phase control accuracy such as interferometric surface figure tests. © 2024 SPIE.

关键词： Adaptive optics

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Modeling and Analysis of Risk Propagation and Loss Causing Capacity for key Nodes in Cyber-Physical Coupled Power Network

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Complex System Modeling and Simulation 2024年第2期4卷 124-136页

作者： Dongqi Liu Qiong Zhang Haolan Liang Tao Zhan Rui Wang National Key Laboratory of Disaster Prevention and Reduction for Power Grid Changsha University of Science and TechnologyChangsha 410114China the School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China the College of Electrical and Information Engineering Hunan Institute of EngineeringXiangtan 411104China the School of Systems Engineering National University of Defense TechnologyChangsha 410003China

The modern power system has evolved into a cyber-physical system with deep coupling of physical and information domains,which brings new security *** at the problem that the“information-physical”cross-domain attacks with key nodes as springboards seriously threaten the safe and stable operation of power grids,a risk propagation model considering key nodes of power communication coupling networks is proposed to study the risk propagation characteristics of malicious attacks on key nodes and the impact on the ***,combined with the complex network theory,a topological model of the power communication coupling network is established,and the key nodes of the coupling network are screened out by Technique for Order Preference by Similarity to Ideal Solution(TOPSIS)method under the comprehensive evaluation index based on topological characteristics and physical ***,a risk propagation model is established for malicious attacks on key nodes to study its propagation characteristics and analyze the state changes of each node in the coupled ***,two loss-causing factors:the minimum load loss ratio and transmission delay factor are constructed to quantify the impact of risk propagation on the coupled ***,simulation analysis based on the IEEE 39-node system shows that the probability of node being breached(α)and the security tolerance of the system(β)are the key factors affecting the risk propagation characteristics of the coupled network,as well as the criticality of the node is positively correlated with the damage-causing *** proposed methodological model can provide an effective exploration of the diffusion of security risks in control systems on a macro level.

关键词： cyber-physical system risk propagation complex network loss causative factor

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RESEARCH PROGRESS AND PROSPECT OF THE HYPERSONIC FLIGHT VEHICLE FAULT-TOLERANT control METHODS 3

RESEARCH PROGRESS AND PROSPECT OF THE HYPERSONIC FLIGHT VEHI...

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3rd International Conference on Mechanical, Aerospace and Automotive Engineering, CMAAE 2023

作者： Fan, Xiaoshuai Qi, Xiaoman Zhang, Shifeng Jiang, Zhenyu College of Aerospace Science and Engineering National University of Defense Technology Changsha China Hunan Provincial Key Laboratory Of Aerospace Cross-Domain Flight Vehicle System and Control Technology Changsha China

ISBN: (纸本)9781839539954

The research status, mathematical models, and fault-tolerant control methods of hypersonic flight vehicles are reviewed. The current research progress of fault-tolerant control methods for hypersonic flight vehicles is summarized based on the typical hypersonic flight vehicles and their mathematical models. The fault-tolerant control methods are mainly divided into active fault-tolerant control and passive fault-tolerant control. The active fault-tolerant control needs to diagnose fault information and carry out fault-tolerant control strategy based on fault diagnosis results. The passive fault-tolerant control should have strong robustness with the design of the control system, it can adaptively suppress the impact of faults without diagnosis when faults occur. The typical fault-tolerant control methods mainly include approximate linear robust control, linear quadratic optimal control, linear parameter varying control, backstepping control, feedback linearization control, sliding mode control. The present status of fault-tolerant control methods of hypersonic flight vehicles and the application of advanced control methods in hypersonic flight vehicles are showed, then the future development trend is forecasted. © The Institution of Engineering & technology 2023.

关键词： Feedback linearization

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Review of X-ray pulsar spacecraft autonomous navigation

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Chinese Journal of Aeronautics 2023年第10期36卷 44-63页

作者： Yidi WANG Wei ZHENG Shuangnan ZHANG Minyu GE Liansheng LI Kun JIANG Xiaoqian CHEN Xiang ZHANG Shijie ZHENG Fangjun LU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Beijing Institute of Control Engineering Beijing 100080China Beijing Institute of Tracking and Communication Technology Beijing 100091China Aerospace Information Research Institute Chinese Academy of ScienceBeijing 100091China Academy of Military Science Beijing 100091China National Innovation Institute of Defense Technology Academy of Military ScienceBeijing 100091China

This article provides a review on X-ray pulsar-based navigation(XNAV).The review starts with the basic concept of XNAV,and briefly introduces the past,present and future projects concerning *** paper focuses on the advances of the key techniques supporting XNAV,including the navigation pulsar database,the X-ray detection system,and the pulse time of arrival ***,the methods to improve the estimation performance of XNAV are ***,some remarks on the future development of XNAV are provided.

关键词： Estimation of pulse time of arrival Spacecraft autonomous navigation X-ray detection X-ray pulsar-based navigation X-ray pulsar signal processing

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Performance of N95 elastomeric respirators in high humidity and high coal dust concentration environment

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International Journal of Mining science and technology 2022年第1期32卷 215-224页

作者： Jintuo Zhu Xinjian He Liang Wang Xiaoxue Liao Guangping Teng Pengli Jing Key Laboratory of Gas and Fire Control for Coal Mines(China University of Mining and Technology) Ministry of EducationXuzhou 221116China National Professional Laboratory for Fundamental Research of Mine Gas and Dust Control Technology School of Safety EngineeringChina University of Mining and TechnologyXuzhou 221116China School of Safety Engineering China University of Mining and TechnologyXuzhou 221116China

High humidity and high dust concentration in deep coal mines may severely challenge the performance of respirators worn by coal *** paper aims at quantitatively evaluating the respirators used in deep coal mines and providing scientific guidance for the respiratory protection of *** on the self-designed in-situ PM2.5 collector,controllable PM2.5 generator,human breathing simulator,and respirator simulation testing system,under the simulated deep mine working condition,this study investigated the effects of dust loading,wearing time,and dust concentration on the filtration efficiency,breathing resistance,and quality factor of N95 elastomeric *** the increase of dust loading,the respirator filtration efficiency firstly decreased,then increased(minimum value 97.5%).The breathing resistance increased exponentially from 120 to 180 to 1020-1530 Pa,and the quality factor decreased logarithmically from 0.051 to 0.076 to 0.0058-0.0085 Pa^(-1).As the PM2.5 coal dust concentration increased from 5 to 50 mg/m^(3),the wearing time for the respirator breathing resistance to exceed 300 Pa reduced from 7 h to less than 1 *** N95 elastomeric respirator is not able to perform an 8-h work *** avoid the excessive breathing resistance caused by dust loading,more filter cartridges are needed for coal miners.

关键词： Coal dust Respirator Dust loading Filtration efficiency Breathing resistance

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3D computational ghost imaging via binocular vision

3D computational ghost imaging via binocular vision

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2022 International Conference on Precision Instruments and Optical Engineering, PIOE 2022

作者： Zhang, Yunhe Chang, Chen Lin, Huizu Sun, Shuai Liu, Weitao Institute for Quantum Science and Technology College of Science National University of Defense Technology Changsha410073 China Hunan Key Laboratory of Mechanism and Technology of Quantum Information Changsha410073 China

ISBN: (纸本)9781510662902

Ghost imaging, a new type of active imaging, has attracted much attention because of its unique imaging mechanism. As an important application of ghost imaging, three-dimensional correlative imaging has been developed in recent years. At present, the main method of 3D ghost imaging is to use the time-of-flight method to obtain the distance from the target object to the imaging system. However, this method is not easy to achieve millimeter-accurate distance measurement in the distance range within 1m because of the limitation of the measuring instruments. In this paper, by using binocular stereo vision which is a more intuitive 3D imaging method combined with computational ghost imaging, millimeter-accurate distance measurement can be performed on objects within 50 cm. Binocular 3D ghost imaging performs well at close range and is relatively simple to implement, which may help robots avoid obstacles and medical imaging. © 2023 SPIE.

关键词： Stereo image processing

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Impact of Skin Temperature control Variable on the Assimilation of Microwave Temperature-sounding Channels in Regional Numerical Weather Prediction

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Advances in Atmospheric sciences 2025年第3期42卷 564-578页

作者： Yaodeng CHEN Qihang YANG Luyao QIN Yuanbing WANG Deming MENG Xusheng YAN Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Key Laboratory of Mesoscale Severe Weather Ministry of EducationSchool of Atmospheric SciencesNanjing UniversityNanjing 210023China

Accurate skin temperature is one of the critical factors in successfully assimilating satellite radiance data over ***,model-simulated skin temperature may not be accurate *** address this issue,an extended skin temperature control variable(TSCV) approach is proposed in a variational assimilation framework,which also considers the background error correlation between skin temperature and atmospheric variables.A series of single observation tests and a 10-day cycling assimilation experiment were conducted to evaluate the impact of the TSCV approach on the assimilation of AMSU-A and ATMS(Advanced technology Microwave Sounder) microwave temperature-sounding channels over *** results of the single observation tests show that by applying the TSCV approach,not only the direct analysis of skin temperature is realized,but also the interaction between skin temperature and atmospheric variables can be achieved during the assimilation *** results of the cycling experiment demonstrate that the TSCV approach improves the skin temperature analysis,which in turn reduces the RMSE of the surface variables and low-level air temperature *** TSCV approach also reduces the difference between the observed and simulated brightness temperatures of both microwave and infrared window channels over land,suggesting that the approach can facilitate the radiance simulation of these channels,thus contributing to the assimilation of window channels.

关键词： radiance assimilation skin temperature control variable microwave temperature-sounding numerical weather prediction

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Attention-Based Residual Dense Shrinkage Network for ECG Denoising

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Computer Modeling in Engineering & sciences 2024年第3期138卷 2809-2824页

作者： Dengyong Zhang Minzhi Yuan Feng Li Lebing Zhang Yanqiang Sun Yiming Ling Hunan Provincial Key Laboratory of Intelligent Processing of Big Data on Transportation Changsha University of Science and TechnologyChangsha410114China School of Computer and Communication Engineering Changsha University of Science and TechnologyChangsha410114China School of Computer and Artificial Intelligence Huaihua UniversityHuaihua418000China School of Computer National University of Defense TechnologyChangsha410073China New Energy Centralized Control Center CHN Energy Hunan Power New Energy Co.Ltd.Changsha410000China

Electrocardiogram(ECG)signal is one of the noninvasive physiological measurement techniques commonly usedin cardiac ***,in real scenarios,the ECGsignal is susceptible to various noise erosion,which affectsthe subsequent pathological ***,the effective removal of the noise from ECG signals has becomea top priority in cardiac diagnostic *** at the problem of incomplete signal shape retention andlow signal-to-noise ratio(SNR)after denoising,a novel ECG denoising network,named attention-based residualdense shrinkage network(ARDSN),is proposed in this ***,the shallow ECG characteristics are extractedby a shallow feature extraction network(SFEN).Then,the residual dense shrinkage attention block(RDSAB)isused for adaptive noise ***,feature fusion representation(FFR)is performed on the hierarchicalfeatures extracted by a series of RDSABs to reconstruct the de-noised ECG *** on the MIT-BIHarrhythmia database and MIT-BIH noise stress test database indicate that the proposed scheme can effectively resistthe interference of different sources of noise on the ECG signal.

关键词： Electrocardiogram signal denoising signal-to-noise ratio attention-based residual dense shrinkage network MIT-BIH

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Motion Reliability Analysis of Retractation Mechanism Based on Co-simulation 6th

Motion Reliability Analysis of Retractation Mechanism Based ...

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6th China Aeronautical science and technology Conference, CASTC 2023

作者： Zhou, Jiyuan Yan, Yumeng Yin, Yin Nie, Hong Wei, Xiaohui State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and Astronautics Nanjing210016 China Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and Astronautics Nanjing210016 China

ISBN: (纸本)9789819988631

The motion reliability of the landing gear retraction mechanism is influenced by multiple random factors during the aircraft’s service life, resulting in poorer motion reliability and undesirable motion characteristics. This paper proposes a method to analyze the motion reliability of the retraction mechanism that considers the influence of multi-source random factors, and the proposed method is applied to the rotatable tire-type landing gear retraction mechanism of a hypersonic vehicle. Then the sources of random factors that affect the performance of the retraction mechanism are thoroughly studied, and the probability method is used to determine the randomness of joint clearances, installation deviations, and aerodynamic load. Additionally, to address the issue of the retraction mechanism failure mode being an implicit function, an estimation model of the motion reliability of the retraction mechanism under multi-source random factors is established. The model is based on the Monte Carlo method and neural network, using a verified co-simulation model of the retraction mechanism. Finally, the impact of the mean and standard deviation of joint clearances, installation deviations, and aerodynamic load on motion reliability is evaluated. key inspection guidelines are also provided for the operation and maintenance of the retraction mechanism. © 2024, Chinese Society of Aeronautics and Astronautics.

关键词： Aerodynamic loads

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Coherent optical link phase noise control based on SPGD algorithm with optimal estimation 6

Coherent optical link phase noise control based on SPGD algo...

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6th Optics Young Scientist Summit, OYSS 2023

作者： Luo, Yihao Zhang, Jun Du, Shiyin Yan, Qiuquan Zhou, Tong Jiang, Tian College of Advanced Interdisciplinary Studies National University of Defense Technology Changsha410073 China National Innovation Institute of Defense Technology Academy of Military Sciences Pla China Beijing100071 China Institute for Quantum Information State Key Laboratory of High Performance Computing College of Computer Science and Technology National University of Defense Technology Changsha410073 China Institute of Quantum Information Science and Technology College of Science National University of Defense Technology Changsha410073 China

ISBN: (纸本)9781510672642

The Stochastic Parallel Gradient Descent (SPGD) algorithm is a widely used model-free optimization algorithm in adaptive optical systems. However, when affected by noise, the SPGD algorithm may incorrectly estimate the gradient, resulting in a significant decrease in its performance and limitations in its application in complex environments. To address this issue, this paper introduces the optimal estimation algorithm and adds a self-checking process to the SPGD algorithm, proposing a Kal-SPGD algorithm. The feasibility of the Kal-SPGD algorithm is verified through simulation and experimentation. The experimental results show that compared with the standard SPGD, the use of the Kal-SPGD algorithm can reduce the signal amplitude variance by up to 92.15%. The Kal-SPGD algorithm provides a more favorable control technique for adaptive optical systems. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.

关键词： Stochastic systems

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