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Defence technology（防务技术） 2024年第7期37卷 162-172页

作者： Pengyu Hu Jiangpeng Wu Zhengang Yan Meng He Chao Liang Hao Bai Xi'an modern control technology Research Institute Xi'an710065China Xi'an OET Science and technology Co. LtdXi'an710076China

High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high ***,it faces challenge in dense objects tracking and 3D trajectories reconstruction due to the characteristics of small size and dense distribution of fragment *** address these challenges,this work presents a warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo ***,background difference algorithm is utilized to extract the center and area of each fragment in the image ***,a multi-object tracking(MOT)algorithm using Kalman filtering and Hungarian optimal assignment is developed to realize real-time and robust trajectories tracking of fragment *** reconstruct 3D motion trajectories,a global stereo trajectories matching strategy is presented,which takes advantages of epipolar constraint and continuity constraint to correctly retrieve stereo correspondence followed by 3D trajectories refinement using polynomial ***,the simulation and experimental results demonstrate that the proposed method can accurately track the motion trajectories and reconstruct the spatio-temporal distribution of 1.0×10^(3)fragments in a field of view(FOV)of 3.2 m×2.5 m,and the accuracy of the velocity estimation can achieve 98.6%.

关键词： Warhead fragment measurement High speed photography Stereo vision Multi-object tracking Spatio-temporal reconstruction

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Optimal Configuration of Fault Location measurement Points in DC Distribution Networks Based on Improved Particle Swarm Optimization Algorithm

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Energy Engineering 2024年第6期121卷 1535-1555页

作者： Huanan Yu Hangyu Li He Wang Shiqiang Li key laboratory of modern Power System Simulation and control&Renewable Energy technology Ministry of EducationNortheast Electric Power UniversityJilin132012China

The escalating deployment of distributed power sources and random loads in DC distribution networks hasamplified the potential consequences of faults if left uncontrolled. To expedite the process of achieving an optimalconfiguration of measurement points, this paper presents an optimal configuration scheme for fault locationmeasurement points in DC distribution networks based on an improved particle swarm optimization ***, a measurement point distribution optimization model is formulated, leveraging compressive *** model aims to achieve the minimum number of measurement points while attaining the best compressivesensing reconstruction effect. It incorporates constraints from the compressive sensing algorithm and networkwide viewability. Subsequently, the traditional particle swarm algorithm is enhanced by utilizing the Haltonsequence for population initialization, generating uniformly distributed individuals. This enhancement reducesindividual search blindness and overlap probability, thereby promoting population diversity. Furthermore, anadaptive t-distribution perturbation strategy is introduced during the particle update process to enhance the globalsearch capability and search speed. The established model for the optimal configuration of measurement points issolved, and the results demonstrate the efficacy and practicality of the proposed method. The optimal configurationreduces the number of measurement points, enhances localization accuracy, and improves the convergence speedof the algorithm. These findings validate the effectiveness and utility of the proposed approach.

关键词： Optimal allocation improved particle swarm algorithm fault location compressed sensing DC distribution network

In-Vehicle Network Injection Attacks Detection Based on Feature Selection and Classification

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Automotive Innovation 2024年第1期7卷 138-149页

作者： Haojie Ji Liyong Wang Hongmao Qin Yinghui Wang Junjie Zhang Biao Chen key laboratory of modern measurement and control technology Ministry of EducationBeijing Information Science and Technology UniversityBeijing 100192China State key laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China School of Transportation Science and Engineering Beihang UniversityBeijing 100191China Hefei Innovation Research Institute Beihang UniversityHefei 230012China

Detecting abnormal data generated from cyberattacks has emerged as a crucial approach for identifying security threats within in-vehicle *** transmission of information through in-vehicle networks needs to follow specific data for-mats and communication protocols ***,statistical algorithms are employed to learn these variation rules and facilitate the identification of abnormal ***,the effectiveness of anomaly detection outcomes often falls short when confronted with highly deceptive in-vehicle network *** this study,seven representative classification algorithms are selected to detect common in-vehicle network attacks,and a comparative analysis is employed to identify the most suitable and favorable detection *** consideration of the communication protocol characteristics of in-vehicle networks,an optimal convolutional neural network(CNN)detection algorithm is proposed that uses data field characteristics and classifier selection,and its comprehensive performance is *** addition,the concept of Hamming distance between two adjacent packets within the in-vehicle network is introduced,enabling the proposal of an enhanced CNN algorithm that achieves robust detection of challenging-to-identify abnormal *** paper also presents the proposed CNN classifica-tion algorithm that effectively addresses the issue of high false negative rate(FNR)in abnormal data detection based on the timestamp feature of data *** experimental results validate the efficacy of the proposed abnormal data detection algorithm,highlighting its strong detection performance and its potential to provide an effective solution for safeguarding the security of in-vehicle network information.

关键词： Classification algorithm Anomaly detection In-vehicle network Feature extraction Injecting attack

Dynamical Modeling and Dynamic Characteristics Analysisof a Coaxial Dual-Rotor System

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Journal of Dynamics, Monitoring and Diagnostics 2024年第2期3卷 99-111页

作者： Yubin Yue Hongjun Wang Shenglun Zhang China Academy of Machinery Science and technology Group Co. Ltd.BeijingChina School of Mechanical and Electrical Engineering Beijing Information Science and Technology UniversityBeijingChina key laboratory of modern measurement and control technology Ministry of EducationBeijing Information Science and Technology UniversityBeijingChina Beijing International Science and technology Cooperation Base of High-end Equipment Intelligent Perception and control Beijing Information Science and Technology UniversityBeijingChina

The dual-rotor structure serves as the primary source of vibration in aero-engines. Understanding itsdynamical model and analyzing dynamic characteristics, such as critical speed and unbalanced response, arecrucial for rotor system dynamics. Previous work introduced a coaxial dual-rotor-support scheme for aeroengines,and a physical model featuring a high-speed flexible inner rotor with a substantial length-to-diameter ratiowas designed. Then a finite element (FE) dynamic model based on the Timoshenko beam elements and rigid bodykinematics of the dual-rotor system is modeled, with the Newmark method and Newton–Raphson method used forthe numerical calculation to study the dynamic characteristics of the system. Three different simulation models,including beam-based FE (1D) model, solid-based FE (3D) model, and transfer matrix model, were designed tostudy the characteristics of mode and the critical speed characteristic of the dual-rotor system. The unbalancedresponse of the dual-rotor system was analyzed to study the influence of mass unbalance on the rotor system. Theeffect of different disk unbalance phases and different speed ratios on the dynamic characteristics of the dual-rotorsystem was investigated in detail. The experimental result shows that the beam-based FE model is effective andsuitable for studying the dual-rotor system.

关键词： coaxial dual-rotor system dynamical modeling dynamic characteristics analysis rotor dynamics

Gut liver brain axis in diseases:the implications for therapeutic interventions

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Signal Transduction and Targeted Therapy 2024年第1期9卷 79-104页

作者： Mengyao Yan Shuli Man Benyue Sun Long Ma Lanping Guo Luqi Huang Wenyuan Gao State key laboratory of Food Nutrition and Safety Key Laboratory of Industrial MicrobiologyMinistry of EducationTianjin Key Laboratory of Industry MicrobiologyNational and Local United Engineering Lab of Metabolic Control Fermentation TechnologyChina International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal ChemistryCollege of BiotechnologyTianjin University of Science&Technology300457 TianjinChina National Resource Center for Chinese Materia Medica China Academy of Chinese Medical Sciences100700 BeijingChina Tianjin key laboratory for modern Drug Delivery&High-Efficiency School of Pharmaceutical Science and TechnologyTianjin UniversityWeijin Road300072 TianjinChina

Gut-liver-brain axis is a three-way highway of information interaction system among the gastrointestinal tract,liver,and nervous *** the past few decades,breakthrough progress has been made in the gut liver brain axis,mainly through understanding its formation mechanism and increasing treatment *** this review,we discuss various complex networks including barrier permeability,gut hormones,gut microbial metabolites,vagus nerve,neurotransmitters,immunity,brain toxic metabolites,β-amyloid(Aβ)metabolism,and epigenetic regulation in the gut-liver-brain *** therapies containing antibiotics,probiotics,prebiotics,synbiotics,fecal microbiota transplantation(FMT),polyphenols,low FODMAP diet and nanotechnology application regulate the gut liver brain ***,some special treatments targeting gut-liver axis include farnesoid X receptor(FXR)agonists,takeda G protein-coupled receptor 5(TGR5)agonists,glucagon-like peptide-1(GLP-1)receptor antagonists and fibroblast growth factor 19(FGF19)*** gut-brain axis embraces cognitive behavioral therapy(CBT),antidepressants and tryptophan metabolism-related *** liver-brain axis contains epigenetic regulation and Aβmetabolism-related *** the future,a better understanding of gut-liver-brain axis interactions will promote the development of novel preventative strategies and the discovery of precise therapeutic targets in multiple diseases.

关键词： metabolism therapeutic immunity

Interaction Quantification of MTDC Systems Connected with Weak AC Grids

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 2088-2099页

作者： Wanning Zheng Jiabing Hu Li Chai Bing Liu Zixia Sang Engineering Research Center of Metallurgical Automation and measurement technology Wuhan University of Science and TechnologyWuhan 430081China State key laboratory of Advanced Electromagnetic Engineering and technology and School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China College of control Science and Engineering Zhejiang UniversityHangzhou 310027China State Grid Hubei Economic Research Institute Wuhan 430077China

The small-signal stability of multi-terminal high voltage direct current(HVDC)systems has become one of the vital issues in modern power *** among voltage source converters(VSCs)have a significant impact on the stability of the *** paper proposes an interaction quantification method based on the self-/en-stabilizing coefficients of the general N-terminal HVDC system with a weak AC network ***,we derive the explicit formulae of self-/en-stabilizing coefficients for any N-terminal HVDC system,which can quantify the interactions through different paths *** relation between the self-/en-stabilizing coefficients and the poles of the system can be used to evaluate the impact of the interactions on the system stability ***,we employ the obtained formulae to analyze the parameter sensitivity and explain how a parameter affects the stability of the system through different paths of ***,extensive examples are given to demonstrate the effectiveness of the proposed method.

关键词： Interactions multi-terminal HVDC self-/enstabilizing coefficients small-signal stability

Anti-saturation fault-tolerant adaptive torsional vibration control with fixed-time prescribed performance for rolling mill main drive system

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Journal of Iron and Steel Research International 2024年第3期31卷 660-669页

作者： Shuang Liu Chen Du Cong Zhang Zhen-hua Bai key lab of Industrial Computer control Engineering of Hebei Province Yanshan UniversityQinhuangdao 066004HebeiChina National Engineering Research Center for Equipment and technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004HebeiChina

An anti-saturation fault-tolerant adaptive torsional vibration control method with fixed-time prescribed performance for the rolling mill main drive system(RMMDS)was investigated,which is affected by control input saturation,actuator faults,sensor measurement errors,and parameter ***,we gave a continuously differentiable saturation function to approximate the control input saturation characteristic of the RMMDS,translating the saturation characteristic into the matched uncertainty and unknown time-varying gain in the ***,an RMMDS mathematical model with unmatched uncertainty and unknown time-varying gain was developed,taking into account the presence of control input saturation,actuator faults,sensor measurement errors,and parameter *** on the established mathematical model,an error transformation model of the roll speed tracking was constructed by the equivalent error transformation *** to the error transformation model,a barrier Lyapunov function and a novel adaptive controller were studied to ensure that the roll speed tracking error always evolves inside a fixed-time asymmetric ***,numerical simulations were performed in Matlab/Simulink to verify the effectiveness and superiority of the proposed control method in suppressing the RMMDS torsional vibration.

关键词： Fixed-time prescribed performance control input saturation Actuator fault Unknown time-varying gain Adaptive control Asymmetric constraint

A real-time performance improvement method for composite time scale

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Chinese Physics B 2024年第9期33卷 350-357页

作者： Fangmin Wang Wenlin Li Hongfei Dai Chunyi Li Jianhua Zhou Shenhui Xue Bo Wang State key laboratory of Precision Space–time Information Sensing technology Department of Precision InstrumentTsinghua UniversityBeijing 100084China key laboratory of Photonic control technology(Tsinghua University) Ministry of EducationBeijing 100084China Beijing Satellite Navigation Center Beijing 100094China

The composite time scale(CTS)provides a stable,accurate,and reliable time scale for modern *** improvement of CTS’s real-time performance will improve its stability,which strengths related applications’*** at this goal,a method achieved by determining the optimal calculation interval and accelerating adjustment stage is proposed in this *** determinants of the CTS’s calculation interval(characteristics of the clock ensemble,the measurement noise,the time and frequency synchronization system’s noise and the auxiliary output generator noise floor)are studied and the optimal calculation interval is *** also investigate the effect of ensemble algorithm’s initial parameters on the CTS’s adjustment stage.A strategy to get the reasonable initial parameters of ensemble algorithm is *** results show that the adjustment stage can be finished rapidly or even can be shorten to zero with reasonable initial *** this basis,we experimentally generate a distributed CTS with a calculation interval of 500 s and its stability outperforms those of the member clocks when the averaging time is longer than1700 *** experimental result proves that the CTS’s real-time performance is significantly improved.

关键词： composite time scale real-time performance calculation interval adjustment stage

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Design and technology review of the solar X-ray detector onboard the Macao Science Satellite-1B

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Science China Technological Sciences 2024年第11期67卷 3365-3380页

作者： ZUO FuChang SHI YongQiang CHEN JianWu ZHANG XiaoPing FU WeiChun CHANG Ye GAI FangQin LIU SiYuan XIONG Yan ZHANG HaiLi SUN Yan WANG Li ZHENG Ran LI LianSheng MEI ZhiWu HUANG He ZHA GangQiang ZHANG KeKe Space Optoelectronic measurement and Perception lab. Beijing Institute of Control Engineering State key laboratory of Lunar and Planetary Sciences Macau University of Science and Technology School of Astronautics Northwestern Polytechnical University key laboratory of Radiation Detection Materials and Devices Northwestern Polytechnical University Research and Development Institute of Northwestern Polytechnical University in Shenzhen

On May 21, 2023, the Macao Science Satellite-1B(MSS-1B), a low-inclination, low-latitude, and high-precision scientific exploration satellite for geomagnetic fields and space environments, was successfully launched. The solar X-ray detector(SXD),one of the two major scientific payloads onboard the MSS-1B, has obtained a large amount of solar X-ray radiation data, which reveals the distribution law of the magnetic field in the low Earth orbit, as well as the coupling law of the Earth's magnetic field and the solar radiation and energy particle distributions. First, the overall design of the multi-detection-unit, broad-energy-range,small-volume, and low-power SXD was implemented to achieve the scientific objectives of the mission. Second, the technical indicators of the instrument were decomposed into various components, and the key technologies, such as collimator, processing circuit, thermal, and payload dataset designs, were reviewed. Third, the backgrounds, including electronic noise, cosmic diffuse X-ray background, and high-energy background in the Earth's radiation belts in and out of the field of view, were analyzed for the instrument. Then, the ground calibrations of the energy response, detection efficiency, and temperature-dependent peak drift of the SXD flight model were conducted. Finally, the in-orbit temperature, energy spectrum data, background, and solar flare process observation of the instrument in the in-orbit test stage are presented, verifying the instrument design, analysis, and ground calibration, providing a foundation for obtaining accurate solar X-ray radiation data, and achieving the scientific objectives of the satellite.

关键词： Macao Science Satellite-1B solar X-ray detector design and development solar flare technology review

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Layer-Valley Hall Effect under Inversion and Time-Reversal Symmetries

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Chinese Physics Letters 2024年第6期41卷 88-97页

作者：赵交交刘贵斌陈鹏姚裕贵张广宇杜罗军 Beijing National laboratory for Condensed Matter Physics and Key Laboratory for Nanoscale Physics and DevicesInstitute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement(MOE)School of PhysicsBeijing Institute of TechnologyBeijing 100081China Beijing key lab of Nanophotonics&Ultrafine Optoelectronic Systems School of PhysicsBeijing Institute of TechnologyBeijing 100081China Schoolof Microelectronics Southern University of Science and TechnologyShenzhen 518055China Songshan Lake Materials laboratory Dongguan 523808China

Hall effects have been the central paradigms in modern physics,materials science and practical applications,and have led to many exciting breakthroughs,including the discovery of topological Chern invariants and the revolution of metrological resistance *** date,the Hall effects have mainly focused on a single degree of freedom(Do F),and most of them require the breaking of spatial-inversion and/or time-reversal *** we demonstrate a new type of Hall effect,i.e.,layer-valley Hall effect,based on a combined layer-valley Do F characterized by the product of layer and valley *** layer-valley Hall effect has a quantum origin arising from the layer-valley contrasting Berry curvature,and can occur in nonmagnetic centrosymmetric crystals with both spatial-inversion and time-reversal symmetries,transcending the symmetry constraints of single Do F Hall effect based on the constituent layer or valley ***,the layer-valley Hall effect is highly tunable and shows a W-shaped pattern in response to the out-of-plane electric ***,we discuss the potential detection approaches and material-specific design principles of layer-valley Hall *** results demonstrate novel Hall physics and open up exotic paradigms for new research direction of layer-valleytronics that exploits the quantum nature of the coupled layer-valley DoF.

关键词： quantum Inversion curvature

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