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A Novel Method for Multi-Function Radar Work Mode Boundary Detection

Progress in Electromagnetics Research C 2025年 153卷 213-218页

作者： Fu, Yuxin Wang, Jiantao Huang, Jie Dang, Tongxin Li, Yiming The National Digital Switching System Engineering and Technological Research and Development Center Zhengzhou450000 China

Work mode boundary detection can provide basic information units for the recognition of consecutive work modes in the intercepted multi-function radar (MFR) pulse sequence. The existing boundary detection methods tend to detect false boundaries when the pulse parameters vary drastically within the work mode, such as when the pulse repetition interval (PRI) modulation type is stagger or agile. To address the issue of over-detection of the work mode transition boundary, a new work mode boundary detection method is proposed based on the arc crossings (AC). It utilizes AC to quantify and annotate the similarities within MFR work modes. Without relying on prior knowledge, it can accurately capture the structural characteristics of the boundary transition and effectively adapt to different pulse parameter modulation types. The experimental results show that it reduces the segmentation probabilistic error by 8.7% and false alarm rate by 19.85% compared to the baseline algorithm. © 2025, Electromagnetics Academy. All rights reserved.

关键词： Tracking radar

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Preparation of ruthenium oxide catalyst for oxygen evolution reaction in HT-PAWE by pulsed electrodeposition

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International Journal of Hydrogen Energy 2024年第PartB期52卷 917-927页

作者： Chen, Tse-Jui Yeh, Tsung-Kuang Wang, Mei-Ya Department of Engineering and System Science National Tsing Hua University Hsinchu Taiwan Nuclear Science and Technology Development Center National Tsing Hua University Hsinchu Taiwan

Despite the fact that the technique of proton exchange membrane water electrolysis (PEMWE) dominates the market because of its low temperature of operation, platinum as a catalyst renders it relatively expensive. In this work, we demonstrated a recyclable ruthenium catalyst with high stability, high oxygen evolution reaction (OER) performance and low onset potential. In particular, instead of PEMWE, the technique of high temperature phosphoric acid water electrolysis (HT-PAWE) was used, with ruthenium oxide as its anode catalyst and a high operation temperature to decrease the amount of noble metals being used. Ruthenium was chosen in this study due to its excellent catalytic activity. The possibility of recycling and reusing noble metals would ease the problem of high cost. Homemade ruthenium catalyst in this study exhibited an outstanding OER performance including high stability and high current density than those of commercial platinum catalyst. Linear sweep voltammetry (LSV) test results showed that a maximum current density of 190 mA/cm2 was reached at only 1.5VSCE. For this experiment, ruthenium (III) chloride hydrate (RuCl3·3H2O) was used as the precursor, and potassium chloride (KCl) and hydrochloric acid (HCl) acted as the supporting electrolyte. Pulsed electrodeposition was chosen to achieve a better control in particle size and distribution of the catalyst over selected specimens. After electrodeposition, the specimens underwent thermal treatment for increasing stability in catalyst particles. Scanning electron microscopy (SEM), linear sweep voltammetry (LSV) and cyclic voltammetry (CV) were used to observe the morphology and to analyze the OER performance of the specimens, respectively. Types of catalyst carrier, electrodeposition potential and duration, and thermal treatment temperature were studied. As a result, all four parameters affected the morphologies and electrochemical performances of the tested specimens. © 2023 Hydrogen Energy Publications LL

关键词： Particle size

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An Attitude Control Scheme for Low Redundancy Micro-nano Satellites without Gyroscopes 7

An Attitude Control Scheme for Low Redundancy Micro-nano Sat...

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7th International Conference on Intelligent Robotics and Control engineering, IRCE 2024

作者： Li, Mingqun Lei, Yongjun Jiang, Qinghua Beijing Institute of Control Engineering Research and Development Center Beijing China Beijing Institute of Control Engineering System Design Department Beijing China

ISBN: (纸本)9798350352399

XX-1 satellite is a micro-nano satellite with low control system redundancy, equipped with only one set of three-axis gyroscopes. How to achieve attitude control during satellite failures has become an important issue in control scheme. This article proposes an attitude control scheme for low redundancy micro-nano satellites under the condition of no gyroscope. When high-value components in the satellite attitude control system, such as gyroscopes, fail and there are no redundant components, the satellite only uses magnetometers to reconstruct the attitude determination system, which can achieve attitude determination under any attitude conditions. This paper divides the working modes of micro-nano satellites into different modes based on the control tasks. Corresponding control laws are adopted in different modes, and magnetic torquers and momentum wheels are used to generate corresponding control torques, thus forming a complete satellite attitude control scheme. This paper further proposes effective discrimination conditions and parameter design methods for various working modes. Mathematical simulation shows that the proposed scheme enables micro-nano satellites to recover from any attitude to a stable operating state without gyroscope, and has the ability to operate stably in orbit for a long time. The attitude control accuracy is better than 2°, and the attitude stability is better than 0.003°/s, greatly improving the satellite's ability to operate safely in orbit. © 2024 IEEE.

关键词： Gyroscopes

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Intelligent recognition and information extraction of radar complex jamming based on time-frequency features

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Journal of systems engineering and Electronics 2024年第5期35卷 1148-1166页

作者： PENG Ruihui WU Xingrui WANG Guohong SUN Dianxing YANG Zhong LI Hongwen College of Information and Communication Engineering Harbin Engineering UniversityHarbin 150001China Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao 266000China Information Fusion Research Institute Naval Aeronautical UniversityYantai 264001China National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of EngineeringWuhan 430033China

In modern war,radar countermeasure is becoming increasingly fierce,and the enemy jamming time and pattern are changing more *** is challenging for the radar to efficiently identify jamming and obtain precise parameter information,particularly in low signal-to-noise ratio(SNR)*** this paper,an approach to intelligent recognition and complex jamming parameter estimate based on joint time-frequency distribution features is proposed to address this challenging ***,a joint algorithm based on YOLOv5 convolutional neural networks(CNNs)is proposed,which is used to achieve the jamming signal classification and preliminary parameter ***,an accurate jamming key parameters estimation algorithm is constructed by comprehensively utilizing chi-square statistical test,feature region search,position regression,spectrum interpolation,etc.,which realizes the accurate estimation of jamming carrier frequency,relative delay,Doppler frequency shift,and other ***,the approach has improved performance for complex jamming recognition and parameter estimation under low SNR,and the recognition rate can reach 98%under−15 dB SNR,according to simulation and real data verification results.

关键词： complex jamming recognition time frequency feature convolutional neural network(CNN) parameter estimation

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An improved air situation assessment method based on intuitive fuzzy reasoning 6

An improved air situation assessment method based on intuiti...

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6th International Conference on Robotics, Intelligent Control and Artificial Intelligence, RICAI 2024

作者： Zhou, Huan Shen, Yue Aviation Engineering School Air Force Engineering University China Research Center of Unmanned System Strategy Development Northwestern Polytechnical University Xi'an China

ISBN: (纸本)9798331541699

Accurately and reliably identifying and predicting the air situation under the conditions of refusal environment and strong confrontation is the prerequisite and foundation for the command and control system to make reasonable task decisions and achieve predetermined goals. In response to this situation assessment issue, this article proposes an improved air situation assessment method based on intuitive fuzzy reasoning, using basic theoretical methods such as fuzzy theory and threat assessment. Firstly, describe the problem of air situation assessment, analyze the characteristics of typical situation assessment methods, and focus on summarizing the shortcomings of current research. Furthermore, utilizing the expressive power of generative adversarial networks and fuzzy reasoning, the situation in the denied air environment is modeled, and an improved air situation evaluation method based on intuitionistic fuzzy reasoning is designed by integrating intuitionistic fuzzy set theory, three-way decision strategy, and cumulative prospect theory. The simulation results show that the proposed Generative Adversarial Intuitive Situation Assessment method can effectively evaluate the current air situation. © 2024 IEEE.

关键词： Generative adversarial networks

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Research on Collaborative Aerial Detection Threat Assessment Method Based on Intuitive Fuzzy Reasoning and Three-way Decision 24

Research on Collaborative Aerial Detection Threat Assessment...

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8th International Conference on Electronic Information Technology and Computer engineering, EITCE 2024

作者： Zhou, Huan Zhao, Xin Shen, Yue Aviation Engineering School Air Force Engineering University Shaanxi Xi'an China Research Center of Unmanned System Strategy Development Northwestern Polytechnical University Shaanxi Xi'an China

ISBN: (纸本)9798400710094

In response to the challenges of high uncertainty in target threat assessment and weak coordination in situational evaluation in unmanned aerial vehicle (UAV) collaborative aerial detection, this paper designs an aerial detection collaborative threat assessment strategy based on fuzzy three support decision-making, effectively solving the problem of fuzzy information processing in aerial detection threat assessment. Firstly, a fuzzy threat model for aerial detection was established, simplifying the difficulty of the problem. Secondly, a threat degree calculation method is constructed using fuzzy multi-attribute decision-making theory, and a threat assessment classification method is constructed based on the fusion of improved prospect theory and three decision-making methods. This strengthens the evaluation algorithm’s ability to process fuzzy information on the field, making the threat assessment and evaluation system more flexible and effective. Subsequently, based on the single aircraft threat assessment results, a coordinated threat item for aerial detection situation was designed to further enhance the formation coordination attribute of unmanned aerial vehicle autonomous threat assessment. Finally, the effectiveness of the designed method was verified through digital simulation in the presence/absence of collaborative aerial detection scenarios, demonstrating its ability to resist fuzzy interference. © 2024 Copyright held by the owner/author(s).

关键词： Aircraft detection

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Improvement in hydrogen storage performance of MgH_(2) by vanadium doped with ZIF-8 derived a single-atom catalyst V-N-C

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Rare Metals 2024年第6期43卷 2623-2635页

作者： Fei-Fan Hong Wei-Tao Shi Ruo-Lin Zhao Yi Fan Zi-Qi Liu Si-Zhi Ding Hai-Zhen Liu Wen-Zheng Zhou Jin Guo Zhi-Qiang Lan Guangxi Novel Battery Materials Research Center of Engineering Technology and Center on Nanoenergy Research Guangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationCarbon Peak and Neutrality Science and Technology Development InstituteSchool of Physical Science and TechnologyGuangxi UniversityNanning 530004China Nanning Engineering Technology Research Center for Power Transmission System of New Energy Vehicle Transportation CollegeNanning UniversityNanning 530200China

Herein,the successful preparation of a singleatom catalyst V-N-C using vanadium-doped zeolitic imidazolate framework(ZIF)-8 as a precursor is *** experimental results showed that the V-N-C had a good promoting effect on the hydrogen storage performance of MgH_(2),and the optimal addition amount of V-N-C was 10wt%.The hydrogenation and dehydrogenation apparent activation energies of 10 wt%V-N-C-catalyzed MgH_(2)were reduced by 44.9 and 53.5 kJ·mol^(-1),respectively,compared to those of additive-free MgH_(2).The 10 wt%V-N-C-catalyzed MgH_(2)could reabsorb 5.92 wt%of hydrogen in 50 min at 150℃,with a capacity retention rate of 99.1%after 30 cycles of hydrogen absorption and *** analysis showed that V-N-C was partially transformed into VN and metallic V when it was milled with MgH_(2);the in-situ-formed VN and metallic V played an important role in improving the hydrogen storage performance of MgH_(2).This approach provides a potential solution for obtaining high-performance Mg-based hydrogen storage materials through synergistic interactions between V,N and C.

关键词： MgH_(2) Hydrogen storage materials Catalyst Hydrogen storage perormance

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Coupling Simulation of the Separation Characteristics of a 'Mussel Type' Elastic Fairing 3

Coupling Simulation of the Separation Characteristics of a '...

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3rd International Symposium on Aerospace engineering and systems, ISAES 2024

作者： Liao, Jiaxin Chen, Gang Zhang, Qingbing Wang, Hao Meng, Dehong He, Houxin Beijing Institute of Electronic System Engineering Beijing100854 China Computational Aerodynamics Institute China Aerodynamics Research and Development Center Mianyang621000 China

ISBN: (纸本)9798350350418

To enhance our understanding of the influence of shell elasticity on the separation dynamics of hypersonic bivalve-type projectiles, this study employs a numerical simulation approach integrating RBD/CSD/CFD. The method successfully yields highly precise simulations, capturing the intricacies of the bidirectional coupling among aerodynamics, structural dynamics, and projectile motion. The investigation, centered on separation motion characteristics, aerodynamic forces, and shell deformation, conducts a comprehensive comparative analysis under varying conditions of dynamic pressure and structural stiffness. Results reveal a gradual increase in the significance of shell elasticity's impact on the separation process with elevated shell dynamic pressure or reduced structural stiffness. Notably, dynamic pressure exhibits a more pronounced effect compared to structural stiffness, yet neither exerts a decisive influence on the elastic bivalve-type separation process. © 2024 IEEE.

关键词： Shells (structures)

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A Method of Magnetometer Relative Reference Calibration for Micro-Nano Satellite and Its Application in Orbit 6

A Method of Magnetometer Relative Reference Calibration for ...

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6th International Conference on Intelligent Robotics and Control engineering, IRCE 2023

作者： Li, Mingqun Liu, Xiang Chen, Shangshang Ma, Kun Jiang, Qinghua Research and Development Center Beijing Institute of Control Engineering Beijing China Beijing Institute of Control Engineering System Design Department Beijing China

ISBN: (纸本)9798350326338

For a low-cost micro-nano satellite that uses magnetometer as the core sensor of attitude determination system, a calibration method of relative reference between multiple magnetometer is proposed. The influence of satellite magnetic environment on magnetic field intensity measurement is studied. After considering remanence, induction and installation deviation, an accurate measurement model of magnetometer is proposed. Without introducing other high-performance attitude sensors, the relative relationship between the measurement data of different magnetometer is derived, and a magnetometer relative reference calibration method based on the least square method is proposed. Mathematical simulation shows that the proposed method reduces the relative measurement error of the magnetometer from 2000 nT to 50 nT, and then uses the telemetry data of the satellite in orbit to calibrate several magnetometer of the satellite. After injecting new parameters, the attitude difference of satellites with different magnetometer as the reference decreases from 16 degrees to less than 2 degrees, indicating that the consistency of the magnetometer reference has been significantly improved, which verifies the effectiveness and practicality of the proposed method. © 2023 IEEE.

关键词： Calibration

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An Integrated Calibration Scheme for Attitude Benchmark of Micro-nano Satellites and Its Experiments Based on In-Orbit Data 8

An Integrated Calibration Scheme for Attitude Benchmark of M...

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8th International Conference on Automation, Control and Robotics engineering, CACRE 2023

作者： Li, Mingqun Luo, Tong Wang, Shaokai Li, He Lei, Yongjun Jiang, Qinghua Beijing Institute of Control Engineering Research and Development Center Beijing China Beijing Institute of Control Engineering System Design Department Beijing China Beijing Institute of Control Engineering Software Development Department Beijing China

ISBN: (纸本)9798350302776

The integrated calibration method of micro-nano satellite attitude benchmark is studied. Considering the magnetic effects and residual magnetism caused by the complex magnetic environment of the satellite, an accurate measurement model for magnetometers was adopted. By using the relationship between the measured and theoretical values of the geomagnetic field, the residual magnetism and magnetic sensitivity coefficients in the magnetometer measurement model were calibrated, through the least square method of uncertain parameters of the calibration. After modeling the installation error of the solar sensor, the calibration of the solar sensor is completed, so as to realize the integrated calibration of the attitude benchmark of the micro-nano satellite. Finally, this article conducted ground experiments using telemetry data from an in orbit satellite. The experimental results showed that the proposed method reduced sensor measurement errors, improved sensor benchmark consistency, and improved attitude determination accuracy from around 10 degrees to better than 0.2 degrees, verifying the effectiveness of the proposed method. © 2023 IEEE.

关键词： Calibration

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