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Science China(Information Sciences) 2025年第1期 292-305页

作者： Tao SHI Wei-Wei CHE School of Mechatronic engineering and automation Shanghai University State Key Laboratory of Synthetical automation for Process Industries Northeastern University College of Information Science and engineering Northeastern University

This article proposes a distributed dynamic event-triggered data-driven iterative learning control(DET-DDILC)scheme under a predefined performance to tackle the bipartite tracking control problem for multiagent systems(MASs). An improved dynamic linearization technique is utilized to convert the nonlinear MASs into an iterative linear data model. First,a peer-to-peer mapping function is introduced to map the constrained distributed system output homeomorphism to an unconstrained one. In addition, a DET mechanism based on a time-iteration-varying function is devised to conserve network communication resources. Based on the unconstrained transformation and the designed DET mechanism, the DET-DDILC algorithm is devised to ensure that the bipartite tracking performance of MASs can be within the preset range. Finally, the effectiveness and feasibility of the designed control scheme are demonstrated via a simulation case by a comparison.

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A new method for early detection of myocardial ischemia:cardiodynamicsgram(CDG)

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Science China(Information Sciences) 2016年第1期59卷 95-105页

作者： Cong WANG Xunde DONG Shanxing OU Wei WANG Junmin HU Feifei YANG College of automation Science and engineering South China University of Technology Department of Radiology General Hospital of Guangzhou Military Command Department 5 of Gerontology General Hospital of Guangzhou Military Command

Early detection of myocardial ischemia via electrocardiographic methods is important and challenging. In the study, based on the standard 12-lead electrocardiography(ECG), a new method called cardiodynamicsgram(CDG) is proposed for early detection of myocardial ischemia. Using a recently proposed deterministic learning algorithm, the cardiodynamics information is extracted from the ST-T segments of standard 12-lead ECG. The CDG is generated by plotting the three-dimensional cardiodynamics information. By analyzing CDG morphology, it is found that significant correlations exist between CDG and ischemia. By evaluating ischemia patients and healthy controls from the Physikalisch-Technische Bundesanstalt(PTB) database and the General Hospital of Guangzhou Military command, the CDG method achieves a mean sensitivity of 90.3% and a mean specificity of 87.8%, which are higher than those of both the standard 12-lead ECG and the exercise ECG. As it is noninvasive, convenient, and inexpensive, it is hopeful that CDG may become a cost-effective screening method for early detection of ischemic heart diseases.

关键词： early detection myocardial ischemia cardiodynamicsgram(CDG) ECG deterministic learning cardiodynamics

Error compensation on precision machine tool servo control system based on digital concave filter

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Journal of Harbin Institute of Technology(New Series) 2001年第4期8卷 389-393页

作者：王立松苏宝库张晶董申 dept. of Control Theory and engineering Harbin Institute of Technology dept. of Computer Science and engineering Harbin Institute of Technology dept. of Mechanical engineering and automation Harbin Institute of Technology

It is concluded from the results of testing the frequency characteristics of the sub micron precision machine tool servo control system, that the existence of several oscillating modalities is the main factor that affects the performance of the control system. To compensate for this effect,several concave filters are utilized in the system to improve the control accuracy. The feasibility of compensating for several oscillating modalities with a single concave filter is also studied. By applying a modified Butterworth concave filter to the practical system, the maximum stable state output error remains under ±10 nm in the closed loop positioning system.

关键词： precision machine tool concave filter oscillating modality

Actively tunable electromagnetically induced transparency in hybrid Dirac-VO2 metamaterials

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Optoelectronics Letters 2025年第1期21卷 13-20页

作者： DI Ke XIE Meng XIA Huarong CHENG Anyu LIU Yu DU Jiajia Department of Optoelectronic engineering Chongqing University of Post and Telecommunications Chongqing Key Laboratory of Autonomous Navigation and Microsystem Chongqing University of Posts and Telecommunications Department of automation Chongqing University of Post and Telecommunications

In this paper, we present a metamaterial structure of Dirac and vanadium dioxide（VO2） and investigate its optical properties using the finite-difference time-domain（FDTD） technique. Using the phase transition feature of VO2, the design can realize active tuning of the plasmon induced transparency（PIT） effect at terahertz frequency, thereby converting from a single PIT to a double-PIT. When VO2is in the insulating state, the structure is symmetric to obtain a single-band PIT effect. When VO2is in the metallic state, the structure turns asymmetric to realize a dual-band PIT effect. This design provides a reference direction for the design of actively tunable metamaterials. Additionally, it is discovered that the transparent window's resonant frequency and the Fermi level in this structure have a somewhat linear relationship. In addition, the structure achieves superior refractive index sensitivity in the terahertz band, surpassing 1 THz/RIU. Consequently, the design exhibits encouraging potential for application in refractive index sensors and optical switches.

关键词： Transparency

Research of the algorithm of the closed-loop control system to control the piezoelectric actuator

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Journal of Harbin Institute of Technology(New Series) 2005年第1期12卷 31-33页

作者：王广林刘胜伟邵东向李云峰 dept. of Mechanical engineering and automation Harbin Institute of Technology Harbin 150001 China

The piezoelectric actuator has been widely used in precision instruments and precision control. However, hysteresis, nonlinearity and creep exist in the actuator, which limit actuator applications and affect accuracy. This thesis introduces fuzzy control as the algorithm of a closed-loop control system to control the piezoelectric actuator. Fuzzy control can make this closed-looped system not only have high linearity, repeatability, accuracy and few overshoot, but isalso easily used.

关键词： piezoelectric actuator position control closed-loop control fuzzy control

Electrocardiogram(ECG) pattern modeling and recognition via deterministic learning

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Control Theory and Technology 2014年第4期12卷 333-344页

作者： Xunde DONG Cong WANG Junmin HU Shanxing OU School of automation Science and engineering South China University of Technology Department of Radiology General Hospital of Guangzhou Military Command

A method for electrocardiogram （ECG） pattern modeling and recognition via deterministic learning theory is presented in this paper. Instead of recognizing ECG signals beat-to-beat, each ECG signal which contains a number of heartbeats is recognized. The method is based entirely on the temporal features （i.e., the dynamics） of ECG patterns, which contains complete information of ECG patterns. A dynamical model is employed to demonstrate the method, which is capable of generating synthetic ECG signals. Based on the dynamical model, the method is shown in the following two phases： the identification （training） phase and the recognition （test） phase. In the identification phase, the dynamics of ECG patterns is accurately modeled and expressed as constant RBF neural weights through the deterministic learning. In the recognition phase, the modeling results are used for ECG pattern recognition. The main feature of the proposed method is that the dynamics of ECG patterns is accurately modeled and is used for ECG pattern recognition. Experimental studies using the Physikalisch-Technische Bundesanstalt （PTB） database are included to demonstrate the effectiveness of the approach.

关键词： ECG Pattern recognition Deterministic learning Dynamics Temporal features

Discussion of the target-missile control scheme with supersonic speed at minimum altitude

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Journal of Harbin Institute of Technology(New Series) 2006年第1期13卷 16-19页

作者：史震于秀萍赵万生 dept. of automation Harbin Engineering University Harbin 150001China dept. of Mechano-Electronic engineering Harbin Institute of Technology Harbin 150001 China

An antiship missile with supersonic speed at minimum altitude is an effective weapon to break through a defense line. The former Soviet Union was a leader in this field since it had developed several kinds of antiship missiles which obtained supersonic speed at minimum altitudes. To counter this kind of missile, many countries have been developing corresponding antimissiles. For the purpose of verifing the antimissile missile′s effectiveness in intercepting antiship missiles, a target-missile is needed. A target-missle is cheaper and can imitate the main characteristics of antiship missiles with supersonic speed at minimum altitude. In this paper, the control scheme of a target missile flying with supersonic speed at minimum altitude is studied. To counter the problem of hedgehopping over the sea, a control scheme utilizing a SINS+altimeter was proposed. In this scheme, both the quick response ability of altitude control and the anti-jamming problem were considered. A simulation experiment shows that when an integrated altitude control system is used, the anti-disturbance ability of the integrated altitude is good and the response speed of altitude control system can be dramatically improved.

关键词： supersonic minimum altitude target missile integrated altitude

FDNet: Fourier transform guided dual-channel underwater image enhancement diffusion network

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Science China Technological Sciences 2025年第1期 62-78页

作者： Zhen ZHU Xiaobo LI Qianwen MA Jingsheng ZHAI Haofeng HU School of Marine Science and Technology Tianjin University College of Mechanical engineering and automation Fuzhou University

Due to the scattering and absorption of light, underwater imaging yields suboptimal results characterized by low brightness, diminished image contrast, and the loss of details. Current learning-based underwater image enhancement(UIE)methods mainly focus on addressing these issues in the spatial domain, with limited attention to the Fourier frequency *** propose the Fourier transform guided dual-channel underwater image enhancement diffusion network(FDNet), aiming to fully leverage frequency domain information and the characteristics of a diffusion-based generation model. The amplitude-phase dualchannel not only effectively provides feedback on the energy distribution of the image but also incorporates crucial image structure and texture information. Capitalizing on these advantages, we first introduce a Fourier transform-based amplitude-phase dualchannel enhancement front-end network for UIE. This network significantly improves the quality of the network's image input,including brightness and contrast, by incorporating phase congruency edge enhancement and prior-driven amplitude mapping strategies. The preceding network mitigates the overall training challenges caused by poor input image quality. Simultaneously,the application of denoising networks based on lightweight transformers effectively improves the computational time required for each iteration during model training. The results indicate that FDNet outperforms many current learning-based UIE algorithms in restoring images across multiple real underwater image datasets, demonstrating more robust generalization capabilities in degraded underwater scenarios. The competitive performance advantage achieved in enhancing visual quality underscores the effectiveness of our method.

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Seismic fragility assessment of existing sub-standard low strength reinforced concrete structures

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Earthquake engineering and engineering Vibration 2015年第3期14卷 439-452页

作者： Sohaib Ahmad Nicolas Kyriakides Kypros Pilakoutas Kyriacos Neocleous Qaiser uz Zaman dept. of Civil and Structural engineering University of Sheffield dept. of Civil engineering and Geomatics Cyprus University of Technology dept. of Civil and Environmental engineering University of Engineering and Technology

An analytical seismic fragility assessment framework is presented for the existing low strength reinforced concrete structures more common in the building stock of the developing *** realistic modelling of such substandard structures,low strength concrete stress-strain and bond-slip capacity models are included in calibrating material *** capacity parameters are generated stochastically to produce building population and cyclic pushover analysis is carried out to capture inelastic *** period values are evaluated corresponding to each displacement step on the capacity curves and used as seismic demand.A modified capacity demand diagram method is adopted for the degrading structures,which is further used to evaluate peak ground acceleration from back analysis considering each point on the capacity curve as performance *** developing fragility curves,the mean values of peak ground acceleration are evaluated corresponding to each performance point on the series of capacity curves.A suitable probability distribution function is adopted for the secant period scatter at different mean peak ground acceleration values and probability of exceedance of limit states is evaluated.A suitable regression function is used for developing fragility curves and regression coefficients are proposed for different confidence *** curves are presented for a low rise pre-seismic code reinforced concrete structure typical of developing countries.

关键词： analytical fragility damage index non-engineered b

Interference Suppression and Jitter Elimination Ability-Based Adaption Tracking Guidance for Robotic Fishes

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 126-137页

作者： Dongfang Li Jie Huang Rob Law Xin Xu Limin Zhu Edmond Q.Wu IEEE the School of Electrical engineering and automation Fuzhou University the Key Laboratory of System Control and Information Processing Ministry of Education the School of Electrical engineering and automation Fuzhou University 5G+Industrial Internet Institute Fuzhou University the University of Macau the College of Mechatronics and automation National University of Defense Technology the School of Mechanical engineering Shanghai Jiao Tong University the Department of Computer Science and engineering Shanghai Jiao Tong University

This work presents an adaptive tracking guidance method for robotic fishes. The scheme enables robots to suppress external interference and eliminate motion jitter. An adaptive integral surge line-of-sight guidance rule is designed to eliminate dynamics interference and sideslip issues. Limited-time yaw and surge speed observers are reported to fit disturbance variables in the model. The approximation values can compensate for the system's control input and improve the robots' tracking ***, this work develops a terminal sliding mode controller and third-order differential processor to determine the rotational torque and reduce the robots' run jitter. Then, Lyapunov's theory proves the uniform ultimate boundedness of the proposed method. Simulation and physical experiments confirm that the technology improves the tracking error convergence speed and stability of robotic fishes.

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