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Linear active disturbance rejection control of fighter aircraft based on MADDPG algorithm

International Journal of systems, control and Communications 2025年第2期16卷 152-172页

作者： Lin, Yetong Ji, Yuehui Song, Yu Liu, Junjie Tianjin Key Laboratory for Control Theory and Applications in Complicated Industry Systems School of Electrical Engineering and Automation Tianjin University of Technology Tianjin300384 China

To address nonlinearity, strong coupling, and disturbances in fighter aircraft attitude control, this paper proposes an intelligent control method based on multi-agent deep deterministic policy gradient (MADDPG) and linear active disturbance rejection control (LADRC). A three-channel LADRC controller estimates and compensates for disturbances, uncertainties, and coupling terms in real time. To overcome the dimensionality curse in multi-parameter optimization, an independent DDPG controller is assigned to each channel, ensuring cooperative control via reward sharing and enhancing dynamic response and disturbance rejection. Additionally, long short-term memory (LSTM) and self-attention mechanisms are integrated into the policy and value networks to improve representation and decision-making. A piecewise combined reward function mitigates sparse rewards. Simulations show that, compared to MADQN-based and traditional LADRC methods, the proposed approach achieves superior control performance and significantly reduces manual parameter tuning efforts. Copyright © 2025 Inderscience Enterprises Ltd.

关键词： Disturbance rejection

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Effect of radical scavenger on electrical tree in cross-linked polyethylene with large harmonic superimposed DC voltage

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High Voltage 2023年第4期8卷 739-748页

作者： Lewei Zhu Zhonglei Li Kai Hou Maritime College Tianjin Key Laboratory for Control Theory and Applications in Complicated Industry SystemsTianjin University of TechnologyTianjinChina Key Laboratory of Smart Grid of Ministry of Education School of Electrical and Information EngineeringTianjin UniversityTianjinChina

In this study,three kinds of radical scavenger Chimassorb 944,Tinuvin 622,and Tinuvin 770 are used to suppress the growth of electrical trees in cross-linked polyethylene(XLPE)with transient superimposed voltage under the temperature *** tree morphology,tree length,accumulated damage,and time to breakdown are used to investigate the effect of radical scavenger on the electrical treeing *** is found that under the temperature gradient caused by the temperature rise on the high voltage side,only Tinuvin 622 can always suppress the electrical tree as the temperature gradient *** the temperature gradient caused by the temperature rise on the ground side,the three radical scavengers can all suppress the electrical *** breakdown of electrical tree exhibits the strong DC polarity ***,energy levels of these three radical scavengers are calculated through quantum chemistry,and the results indicate that radical scavengers have greater electron affinity,smaller ionisation energy,and smaller energy gap than *** to the surface potential decay test results at 60℃,it is found that all three radical scavengers can introduce deep *** different performances of radical scavengers under different temperature gradients and voltages are determined by the trap distribution characteristics,the molecular structure and chemical reaction of the additives *** is concluded that Tinuvin 622 has potential for use in high voltage direct current XLPE cable application.

关键词： radical electrical harmonic

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A Method for Allocating Hybrid Teaching Credit Hours Using Hierarchical Analysis 25

A Method for Allocating Hybrid Teaching Credit Hours Using H...

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25th IEEE China Conference on System Simulation Technology and its Application, CCSSTA 2024

作者： Meng, Xiangang Li, Xiaojing Xu, Liang School of Electrical Engineering and Automation Tianjin University of Technology Tianjin Key Laboratory for Control Theory & Applications in Complicated Systems Tianjin China

ISBN: (纸本)9798350366600

Hybrid teaching combines traditional teaching and flipped classroom, which is a new teaching mode with the advantages of both modes. In hybrid teaching mode, reasonable allocation of credit hours between traditional teaching and flipped classroom is an important issue for the teaching work. This paper first proposes a method of using hierarchical analysis to allocate credit hours for hybrid teaching of Digital Electronic Technology courses. Firstly, we divided hybrid teaching into stage and content layers, and determined the various elements of stage and content layers. Secondly, the requirements of the Analytic Hierarchy Process were applied to organize these two levels, and pairwise importance comparisons were made for each element within the level. Index judgment matrices were established for the stage level and content level, respectively. Then, the calculation steps of the Analytic Hierarchy Process were designed, and matrix operations were used to obtain the normalized weights of each element in the stage and content layers of traditional teaching and flipped classrooms. This weight was used to determine the class hours to be allocated for each stage and content. Finally, the feasibility and effectiveness of the method proposed in this paper were verified using the example of hybrid teaching hour allocation in Chapter 4 of the Digital Electronic Technology course at Tianjin University of Technology. © 2024 IEEE.

关键词： Hierarchical systems

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Predefined time backstepping control of photovoltaic grid connected inverter 6

Predefined time backstepping control of photovoltaic grid co...

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2023 6th International Conference on Power Electronics and control Engineering, ICPECE 2023

作者： Xu, Zhao Ji, Yuehui Chen, Jiaqi Liu, Junjie The School of Electrical Engineering and Automation Tianjin University of Technology Tianjin300384 China Tianjin Key Laboratory for Control Theory and Applications in Complicated Industry Systems Tianjin300384 China

The large-scale grid connection of photovoltaic (PV) systems creates great hazards to the operation of power equipment and has a great impact on the stability and reliability of power systems. To achieve stable control and flexible management of PV grid connection, a predefined time adaptive backstepping control method based on the predefined boundary is proposed. Based on the predefined boundary time-varying function, the user's predefined boundary design of the control signal is accomplished to ensure the boundedness of the global signal, which is independent of the initial state of the system. The controller with predefined boundaries is designed based on backstepping control, and the estimation and compensation of perturbations are attained based on adaptive control. The global predefined time stability of the predefined boundary of the closed-loop system is certified using the Lyapunov function. Simulation studies attest to the performance of the predefined time control strategy. © Published under licence by IOP Publishing Ltd.

关键词： Lyapunov functions

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Distributed-Observer-Based on Longitudinal Flight control for Hypersonic Vehicle 42

Distributed-Observer-Based on Longitudinal Flight Control fo...

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42nd Chinese control Conference, CCC 2023

作者： Ji, Yuehui Zhao, Yiming Chen, Jiaqi Liu, Junjie Gao, Qiang School of Electrical Engineering and Automation Tianjin University of Technology Tianjin Key Laboratory for Control Theory & Applications in Complicated Systems Tianjin300384 China

ISBN: (纸本)9789887581543

An output feedback control is investigated to achieve stable tracking of velocity and altitude in hypersonic flight vehicle in the paper. A distributed observer is proposed to estimate the unmeasurable flight path angel and angle of attack through a strongly connected directed network topology. Then, a nonlinear control is addressed on the longitudinal dynamics of a rigid hypersonic flight vehicle (HFV) with partial measurable states and the estimated states. The system dynamic is divided into the altitude subsystem and the velocity subsystem. In the altitude subsystem, the backstepping design is proposed for constructing the controllers utilizing the estimated states. The nonlinear dynamic inversion controller is introduced to accomplish the velocity tracking. Finally, numerical simulations verify the effectiveness of the proposed control scheme in providing favorable tracking performance and exact state estimation ability. © 2023 Technical Committee on control theory, Chinese Association of Automation.

关键词： Hypersonic vehicles

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Threshold Voltage Monitoring Method of SiC MOSFET Considering the Influence of Thermoelectric Coupling 10th

Threshold Voltage Monitoring Method of SiC MOSFET Considerin...

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10th Frontier Academic Forum of Electrical Engineering, FAFEE 2022

作者： Liu, Yulin Du, Mingxing Yin, Jinliang Wei, Yifan Tianjin Key Laboratory of Control Theory and Applications in Complicated System Tianjin University of Technology Tianjin300384 China

ISBN: (纸本)9789819934034

Silicon carbide has a wider band gap and higher interface trap density. The threshold voltage shift caused by bias temperature instability is a challenge to the reliability of SiC MOSFET. In practical applications, the threshold voltage will change in real time with the change of power loss and junction temperature caused by the cooling system. Therefore, it is necessary to monitor the threshold voltage shift considering BTI and junction temperature, which is of great significance to the reliability research of SiC MOSFET. In this paper, we first analyze the components and temperature sensitivity of SiC MOSFET on-state drain-source resistance, then study the influence mechanism of bias temperature instability on chip resistance, and finally propose to use SiC MOSFET chip drain-source on-state resistance to monitor the threshold voltage shift caused by the coupling of junction temperature and bias temperature instability. This method can directly obtain the shift threshold voltage through the chip drain source on state resistance. It is also suitable for SiC MOSFET modules with anti-parallel diodes. Considering the influence of temperature, this method can realize the accurate monitoring of threshold voltage under complex working conditions. © Beijing Paike Culture Commu. Co., Ltd. 2023.

关键词： Junction temperature

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Path Tracking Motion control Method Of Tracked Robot Based On Improved LQR control 41

Path Tracking Motion Control Method Of Tracked Robot Based O...

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第41届中国控制会议

作者： Jianyun Ni Yong Wang Hao Li Helei Du Tianjin Key Laboratory for Control Theory & Applications in Complicated Systems School of Electronic Engineering and Automation Tianjin University of Technology

ISBN: (数字)9789887581536

ISBN: (纸本)9781665482561

In order to enhance the trajectory tracking control performance of tracked mobile robot,an improved LQR lateral motion control method is ***,the robot tracking error kinematics model is constructed by using Lagrange function method,and the linear quadratic regulator controller(LQR) and feedforward controller of the tracked mobile robot are ***,the parameters of LQR controller are analyzed,the Q and R weight coefficient matrix of LQR controller is optimized,and the fast rolling optimization algorithm of lateral tracking control based on path tracking error is *** this way,the improvement of the LQR controller is realized,and the adaptability and control accuracy of the controller and the dynamic performance of the system are ***,test the designed controller through Matlab/Simulink *** simulation results show that the improved LQR controller can track the target path well,and can control the distance deviation and heading deviation in a small range.

关键词： Tracked Mobile Robot LQR Path Tracking Motion control

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Output Regulation for Multi-Quadrotor by Event-Triggered Mechanism

Output Regulation for Multi-Quadrotor by Event-Triggered Mec...

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International Conference on Guidance, Navigation and control, ICGNC 2020

作者： Che, Shixing Gao, Qiang Ji, Yuehui Tianjin Key Laboratory for Control Theory and Applications in Complicated Systems Tianjin University of Technology Tianjin China

ISBN: (纸本)9789811581540

To accomplish the stable tracking of the multi-quadrotor, an attitude controller based on output regulation and event triggered control (ETC) is proposed to save communication and computing resources effectively. Aiming at the problems of asymptotically tracking and rejecting disturbances, a dynamic compensator, i.e., a novel internal model is designed to convert the output regulation problem of the multi-quadrotor system into the robust stabilization problem of augmented system. The designed internal model studies the desired state and desired input for each quadrotor which depends on the sampled signal of the adjacent quadrotor and itself. To this end, a novel distributed event triggered mechanism (DETM) that exclude Zeno phenomenon and a novel distributed event triggered control law (DETCL) are adopted. The stability and boundedness of all signals in the multi-quadrotor system are proved by Lyapunov method. At last, numerical simulation verify the availability of the controller in providing satisfactory tracking response and saving control energy. © 2022, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Attitude control

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Aero-optic imaging deviation prediction based on ISSA-ELM

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Optoelectronics Letters 2023年第7期19卷 425-431页

作者： XU Liang ZHAO Shiwei WANG Tao Tianjin Key Laboratory for Control Theory&Applications in Complicated Systems School of Electrical Engineering and AutomationTianjin University of TechnologyTianjin 300384China School of Intelligent Engineering Sun Yat-sen UniversityGuangzhou 510275China

When the aircraft is moving at high speed in the atmosphere,aero-optical imaging deviation will appear due to the influence of aero-optical *** order to achieve real-time compensation during the flight of the aircraft,it is necessary to analyze and predict the obtained imaging deviation *** order to improve the search speed and accuracy of the prediction algorithm and the ability to jump out of local optimum,in this paper,an improved sparrow search algorithm optimized extreme learning machine(ISSA-ELM) neural network model is proposed to predict the aero-optical imagine ***,the performance of ISSA-ELM,ELM neural network and SSA-ELM neural network was *** results showed that compared with ELM and SSA-ELM algorithms,the convergence speed of ISSA-ELM was significantly enhanced,and the accuracy of data prediction was also significantly improved.

关键词： effect. deviation extreme

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Named Entity Recognition in Chinese Medical Texts Based on RoBERTa-WWM-IDCNN-CRF 25

Named Entity Recognition in Chinese Medical Texts Based on R...

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25th IEEE China Conference on System Simulation Technology and its Application, CCSSTA 2024

作者： Tang, Lan Kong, Jie Xu, Liang Xi'an Shiyou University School of Computer Xi'an China Tianjin University of Technology Tianjin Key Laboratory for Control Theory & Applications in Complicated Systems School of Electrical Engineering and Automation Tianjin China

ISBN: (纸本)9798350366600

Electronic medical records and doctor-patient conversations contain a wealth of useful information, such as disease symptoms, drug names, and cure cycles. Traditional deep learning approaches utilize bidirectional recurrent neural networks to encode text, which cannot effectively capture long-distance dependencies in text. In order to identify medical entity types in various texts more accurately, a named entity recognition approach based on RoBERTa-WWM-IDCNN-CRF is proposed. This approach introduces the RoBERTa-WWM pre-trained model, in order to improve the overall understanding of long Chinese texts for the first time. The model generates semantic representations containing prior knowledge. Then, the generated semantic representations are feed to the IDCNN to extract sentence level characteristics. Finally, the global optimal solution is obtained and the results of the named entity are produced through the CRF. The experiment indicates that the improvement of F1 score, accuracy, and recall of RoBERTa-WWM-IDCNN-CRF model are 7.94%, 4.52% and 10.02% comparing with the classical BiLSTM-CRF model. © 2024 IEEE.

关键词： Convolutional neural networks

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