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IEEE Transactions on Sustainable Computing 2024年第3期10卷 475-490页

作者： Song, Changqing Zhao, Hongzhi Yu, Yong Li, Zhuo Shao, Shihai University of Electronic Science and Technology of China National Key Laboratory of Wireless Communications Chengdu611731 China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing100089 China Yangzhou Marine Electronic Instrument Institute Yangzhou225101 China

The artificial noise shielded frequency-hopping (ANFH) architecture can secure wireless communications against interference and eavesdropping. However, the AN suppression performance is highly sensitive to the radio frequency (RF) impairments, and the transceiver in-phase and quadrature (IQ) imbalances and phase noise in FH systems are more severe for the wide FH bandwidth. In this study, the AN-FH transceivers under RF impairments are mathematically modeled. Subsequently, distortions for transceiver phase noise are represented by the common phase error, distortions for transceiver IQ imbalances are represented by the mirror image component, and closed-form expressions for their respective power are derived and compared with the thermal noise power. Finally, the AN suppression capability is evaluated via the AN suppression ratio (ANSR), defined as the ratio of the AN-plus-noise power before and after suppression. It is found that when only phase noise exists, shortening the channel compensation cycle can enhance ANSR and reduce ANSR degradation;when the distortions' power is smaller than the thermal noise power, it is also recommended to enhance the transmitting power and the power ratio of AN to information signals. When only IQ imbalances exist, increasing the power ratio of AN to information signals is suggested;when the distortions' power is smaller than the thermal noise power, enhancing the transmitting power is also suggested © 2016 IEEE.

关键词： Phase noise

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Robust Bounded-H8 control for High-Order Fully Actuated Systems Based on FAS Approaches 3

Robust Bounded-H8 Control for High-Order Fully Actuated Syst...

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3rd Conference on Fully Actuated System Theory and Applications, FASTA 2024

作者： Hu, Liyao Duan, Guangren Harbin Institute of Technology Center for Control Theory and Guidance Technology Harbin150001 China Southern University of Science and Technology Shenzhen Key Laboratory of Control Theory and Intelligent Systems Shenzhen518055 China

ISBN: (纸本)9798350373691

This paper investigates the robust bounded-H8 stabilization for a class of high-order fully actuated systems (FASs) with time-varying uncertainty and disturbance. Based on the FAS approaches and the H8 control, a robust bounded-H8 controller is designed, which guarantees that the system state and its derivatives of each order are globally bounded. Furthermore, a combined disturbance, composed of part time-varying uncertainty and disturbance, is given. With the help of the combined disturbance, the impact of the uncertainty and the disturbance on system output can be attenuated simultaneously, because the closed-loop high-order FAS has the bounded-H8 performance. A simulation example is provided to demonstrate the effectiveness of the proposed control method. © 2024 IEEE.

关键词： Robust control

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Liquid-filled spacecraft finite-time attitude maneuver control with attitude and angular velocity constraints 74

Liquid-filled spacecraft finite-time attitude maneuver contr...

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74th International Astronautical Congress, IAC 2023

作者： Guo, Yanning Zhang, Wei Ma, Guangfu Lyu, Yueyong Zhang, Haibo Harbin Institute of Technology China Beijing Institute of Control Engineering China National Key Laboratory of Science and Technology on Space Intelligent Control China

With development of aerospace industry, the mass of liquid fuel carried by spacecraft is also increasing in order to complete more complex space exploration missions, such as on-orbit refueling and space debris removal. And there is large liquid fuel consumption when spacecraft completes attitude and orbit maneuver, which greatly increases the nonlinearity and uncertainty of spacecraft dynamics and brings great challenges to spacecraft attitude maneuver control. Considering that during attitude maneuver, the control torque is easy to stimulate the liquid slosh, which will affect the attitude control performance and even lead to instability of the system. So it is necessary to constrain the angular velocity during attitude maneuver. In this paper, we consider the large angle attitude maneuver control of liquid-filled spacecraft system. Because of the consumption of liquid fuel, then the mass property of system is unknown and slowly time varying. So a novel finite-time attitude maneuver control law based on barrier Lyapunov function (BLF) and backstepping method in the presence of unknown, time varying system dynamics and angular velocity constraint, which aims at avoidance of violent liquid slosh, is proposed in this paper. Firstly, the sloshing liquid in a partially filled tank carried by the spacecraft is equivalent to a sloshing slug - a sphere of uniform density with a variable radius, and the rigid-liquid coupling dynamic equations with unknown parameters of the spacecraft are deduced by using the law of conservation of moment of momentum. Secondly, a finite-time prescribed performance function (FTPPF) is proposed to guarantee the convergence of spacecraft attitude error to zero within the setting time, with the help of FTPPF and the angular velocity constraint, a time-varying BLF and a logarithmic BLF are proposed correspondingly. Furthermore, a backstepping control law is designed for the spacecraft attitude maneuver based on augmented Lyapunov functions, mean

关键词： Angular velocity constraint Attitude constraint Backstepping control Backstepping control Liquid-filled spacecraft

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Negative self-feedback induced enhancement and transition of spiking activity for class-3 excitability

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Chinese Physics B 2022年第7期31卷 203-213页

作者： Li Li Zhiguo Zhao Huaguang Gu Guangdong Key Laboratory of Modern Control Technology Institute of Intelligent ManufacturingGuangdong Academy of SciencesGuangzhou 510070China School of Science Henan Institute of TechnologyXinxiang 453003China School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China

Post-inhibitory rebound(PIR)spike,which has been widely observed in diverse nervous systems with different physiological functions and simulated in theoretical models with class-2 excitability,presents a counterintuitive nonlinear phenomenon in that the inhibitory effect can facilitate neural firing *** this study,a PIR spike induced by inhibitory stimulation from the resting state corresponding to class-3 excitability that is not related to bifurcation is simulated in the Morris–Lecar ***,the inhibitory self-feedback mediated by an autapse with time delay can evoke tonic/repetitive spiking from phasic/transient *** dynamical mechanism for the PIR spike and the tonic/repetitive spiking is acquired with the phase plane analysis and the shape of the quasi-separatrix *** result extends the counterintuitive phenomenon induced by inhibition to class-3 excitability,which presents a potential function of inhibitory autapse and class-3 neuron in many neuronal systems such as the auditory system.

关键词： post-inhibitory rebound spike class 3 excitability inhibitory autapse neuronal firing

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Q-Learning-Based Target Selection for Bearings-Only Autonomous Navigation

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Journal of Systems science & Complexity 2021年第4期34卷 1401-1425页

作者： XIONG Kai WEI Chunling Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control EngineeringBeijing 100094China

This paper presents a Q-learning-based target selection algorithm for spacecraft autonomous navigation using bearing observations of known visible *** the considered navigation system,the position and velocity of the spacecraft are estimated using an extended Kalman filter(EKF)with the measurements of inter-satellite line-of-sight(LOS)vectors obtained via an onboard star *** paper focuses on the selection of the appropriate target at each observation period for the star camera adaptively,such that the performance of the EKF is *** derive an effective algorithm,a Q-function is designed to select a proper observation region,while a U-function is introduced to rank the targets in the selected *** the Q-function and the U-function are constructed based on the sequence of innovations obtained from the *** efficiency of the Q-learning-based target selection algorithm is illustrated via numerical simulations,which show that the presented algorithm outperforms the traditional target selection strategy based on a Cramer-Rao bound(CRB)in the case that the prior knowledge about the target location is inaccurate.

关键词： Bearings-only autonomous navigation convergence analysis extended Kalman filtering Q-Learning target selection

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Image Recognition and Analysis of Computer Interlock Interface Based on OpenCV technology 6

Image Recognition and Analysis of Computer Interlock Interfa...

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6th IEEE Advanced Information Management, Communicates, Electronic and Automation control Conference, IMCEC 2024

作者： Chen, Xuanmo Li, Qiang Lanzhoujiaotong University College of Computer Science and Technology Lanzhou China Ministry of Education Province Key Laboratory of Optoelectronic Technology and Intelligent Control Lanzhou China

ISBN: (纸本)9798350316520

An integrated computerized locking mechanism is vital for upholding the safety of train movements within railway networks. As computer technology progresses swiftly, conventional locking systems are encountering a multitude of difficulties, with the identification and processing of visual interface data being a key challenge. Furthermore, the pace of technological innovation has led to an array of other obstacles for these systems to surmount. The deployment of cutting-edge technologies, including AI and machine learning, has markedly enhanced the functionality and security of these mechanisms. Anticipatedly, the future will witness the development of even more sophisticated and secure railway traffic management systems. These evolving technologies serve as formidable instruments in tackling the prevailing issues and challenges. Specifically, the computerized interface locking system is indispensable in guaranteeing the safe running of trains within railway *** paper applies the image processing capability of OpenCV to preprocess and extract characteristics from the interlocking interface image. Subsequently, the enhanced clustering algorithm of RV-DBSCAN is utilized to identify the text of signaling equipment diagrams, followed by the implementation of the Paddle OCR (Optical Character Recognition) machine learning algorithm to classify and identify the images. The recognition accuracy rate for information related to railway signaling equipment stands at 92.6%. This process offers a dependable approach for extracting and recognizing station information from computerized interlocking interfaces. © 2024 IEEE.

关键词： Clustering algorithms

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HWD-YOLO:A New Vision-Based Helmet Wearing Detection Method

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Computers, Materials & Continua 2024年第9期80卷 4543-4560页

作者： Licheng Sun Heping Li Liang Wang College of Information Science and Technology Beijing University of TechnologyBeijing100124China Chinese Institute of Coal Science Beijing100013China State Key Laboratory for Intelligent Coal Mining and Strata Control Beijing100013China Engineering Research Center of Digital Community of Ministry of Education Beijing100124China

It is crucial to ensure workers wear safety helmets when working at a workplace with a high risk of safety accidents,such as construction sites and mine *** existing methods can achieve helmet detection in images,their accuracy and speed still need improvements since complex,cluttered,and large-scale scenes of real workplaces cause server occlusion,illumination change,scale variation,and perspective ***,a new safety helmet-wearing detection method based on deep learning is ***,a new multi-scale contextual aggregation module is proposed to aggregate multi-scale feature information globally and highlight the details of concerned objects in the backbone part of the deep neural ***,a new detection block combining the dilate convolution and attention mechanism is proposed and introduced into the prediction *** block can effectively extract deep featureswhile retaining information on fine-grained details,such as edges and small ***,some newly emerged modules are incorporated into the proposed network to improve safety helmetwearing detection performance *** experiments on open dataset validate the proposed *** reaches better performance on helmet-wearing detection and even outperforms the state-of-the-art *** be more specific,the mAP increases by 3.4%,and the speed increases from17 to 33 fps in comparison with the baseline,You Only Look Once(YOLO)version 5X,and themean average precision increases by 1.0%and the speed increases by 7 fps in comparison with the YOLO version *** generalization ability and portability experiment results show that the proposed improvements could serve as a springboard for deep neural network design to improve object detection performance in complex scenarios.

关键词： Object detection deep learning safety helmet wearing detection feature extraction attention mechanism

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Simulation of Nanosecond Microwave Pulse Amplification Based on a Gyrotron Traveling Wave Tube

Simulation of Nanosecond Microwave Pulse Amplification Based...

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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Pan, Ruoyang Zhang, Zhiyuan Liu, Guo Wang, Weijie Yao, Yelei Jiang, Wei Wu, Zewei Pu, Youlei Wang, Jianxun Luo, Yong University of Electronic Science and Technology of China School of Electronic Science and Engineering Chengdu China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing China

ISBN: (纸本)9798350375909

The paper presents the simulation results for nanosecond pulse amplification utilizing a TE11 mode Ku-band gyrotron traveling wave tube (gyro-TWT). This study evaluates the output performance across various input pulse widths within the 15-17 GHz frequency range. Simulations show that the minimum output pulse width is 0.8 ns, with an output power of 183.9 kW. Moreover, when input pulse widths exceed 2 ns, it is observed that the tube can attain a saturated output power of 293.1 kW, with negligible disparity between input and output pulse widths. The gyro-TWT can serve as a nanosecond pulse source, with potential applications in fields such as military radar, biomedicine, and microwave chemistry. © 2024 IEEE.

关键词： Military radar

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A FAS approach for stabilization of generalized chained forms: part 2. Continuous control laws

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science China(Information sciences) 2024年第3期67卷 114-135页

作者： Guang-Ren DUAN Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and Technology Center for Control Theory and Guidance Technology Harbin Institute of Technology

In this paper, continuous time-varying stabilizing controllers for the type of general nonholonomic systems proposed and treated in part 1 are designed using the fully actuated system(FAS) approach. The key step is to differentiate the first scalar equation, and by control of the obtained second-order scalar system, a proportional plus integral feedback form for the first control variable is obtained. With the solution to this designed second-order scalar system, the rest equations in the nonholonomic system form an independent time-varying subsystem which is then handled by the FAS approach. The overall designed controller contains an almost arbitrarily chosen design parameter, and is proven to guarantee the uniformly and globally exponential stability of the closed-loop system. The proposed approach is simple and effective,and is demonstrated with a practical example of ship control.

关键词： nonholonomic systems feedback stabilization fully actuated systems Lyapunov stability continuous controllers

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Shear behaviour of anchored jointed rock mass under different engineering conditions considering damage and joint surface morphology

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Underground Space 2023年第6期13卷 316-334页

作者： Zenghui Zhao Wei Sun Shaojie Chen Hao Liu College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Strata Intelligent Control and Green Mining Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China Department of Petroleum Engineering China University of Petroleum-BeijingBeijing 102249China

According to different geological conditions and engineering disturbance,three dimensional numerical models of anchored jointed rock mass with two kinds of boundary conditions of constant normal load(CNL)and constant normal stiffness(CNS)were constructed considering the ductility damage of rockbolt,the stiffness degradation of grouting layer and the joint surface *** effects of anchorage angle,joint surface morphology,and boundary conditions on the shear performance of anchorage system were analyzed,and the failure characteristics under different working conditions were ***,the analytical solution of shear strength of anchored system was *** show that the larger the anchorage angle is,the more serious the necking phenomenon of rockbolt will *** damage degree of the bonding layer and the horizontal displacement of the bedding rock mass decrease with the increase of the joint surface *** CNL condition is to instantaneously apply high normal stress,and the CNS condition is to gradually form a high normal stress environment through the superposition of increment on the basis of the initial value,which can resist greater transverse *** is equivalent to enhancing the ductility of the *** shear strength of the system increases with the increase of normal stress and normal *** the normal stiffness will underestimate the shear strength.

关键词： Anchored jointed rock mass Normal stress Normal stiffness Progressive damage

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