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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1557-1565页

作者： Jin-Xi Zhang Kai-Di Xu Qing-guo Wang IEEE the State Key Laboratory of Synthetical automation for Process Industries Northeastern UniversityShenyang 110819China Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087 Guangdong Key Laboratory of Artificial Intelligence and Multi-Modal Data Processing Beijing Normal University-Hong Kong Baptist University United International CollegeZhuhai 519087

The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this ***, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings.

关键词： Nonlinear systems output constraints prescribed performance reference tracking time delays

Method for rapid warning and activity concentration estimates in online waterγ-spectrometry systems

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Nuclear Science and Techniques 2024年第3期35卷 1-12页

作者： Meng Wang Yi Gu Mao-Lin Xiong Liang-Quan Ge Qing-Xian Zhang guo-Qiang Zeng Heng Lu Sheng-Liang guo college of Nuclear Technology and automation Engineering Chengdu University of TechnologyChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province (Chengdu University of Technology)Chengdu 610059China Chengdu New Ray Technology Co.Ltd Chengdu 610052China

Onlineγ-spectrometry systems for inland waters,most of which extract samples in situ and in real time,are able to produce reliable activity concentration measurements for waterborne radionuclides only when they are distributed relatively uniformly and enter into a steady-state diffusion regime in the measurement *** protect residents’health and ensure the safety of the living environment,better timeliness is required for this measurement *** address this issue,this study established a mathematical model of the online waterγ-spectrometry system so that rapid warning and activity estimates can be obtained for water under non-steady-state(NSS)*** addition,the detection efficiency of the detector for radionuclides during the NSS diffusion process was determined by applying the computational fluid dynamics technique in conjunction with Monte Carlo *** this basis,a method was developed that allowed the online waterγ-spectrometry system to provide rapid warning and activity concentration estimates for radionuclides in *** analysis of the NSS-mode measurements of^(40)K radioactive solutions with different activity concentrations determined the optimum warning threshold and measurement time for producing accurate activity concentration estimates for *** experimental results show that the proposed NSS measurement method is able to give warning and yield accurate activity concentration estimates for radionuclides 55.42 and 69.42 min after the entry of a 10 Bq/L^(40)K radioactive solution into the measurement chamber,*** times are much shorter than the 90 min required by the conventional measurement ***,the NSS measurement method allows the measurement system to give rapid(within approximately 15 min)warning when the activity concentrations of some radionuclides reach their respective limits stipulated in the Guidelines for Drinking-water Quality of the WHO,suggesting that this method con

关键词： Water radioactivity monitoring Dynamic detection efficiency Rapid warning Activity estimation

Double-branch forgery image detection based on multi-scale feature fusion

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Optoelectronics Letters 2024年第5期20卷 307-312页

作者： ZHANG Hongying guo Chunxing WANG Xuyong college of Electronic Information and automation Civil Aviation University of ChinaTianjin 300300China

Most of existing methods exhibit poor performance in detecting forged images due to the small size of tampered areas and the limited pixel difference between untampered and tampered regions. To alleviate the above problem, a double-branch tampered image detection based on multi-scale features is proposed. Firstly, we introduce a fusion module based on attention mechanism in the first branch to enhance the network's sensitivity towards tampered regions. Secondly, we construct a second branch specifically designed for detection, aiming to identify subtle differences between tampered and untampered areas by utilizing rich edge information from shallow features as guidance. Compared to the existing methods on the public benchmark datasets CASIA1.0, Columbia and NIST16, the values of F-score reached 0.766, 0.900 and 0.930 on those datasets, respectively. The experimental results show that our method could significantly improve the accuracy on detecting the tampered area.

关键词： branch image utilizing

GPU-accelerated OCT imaging: Real-time data processing and artifact suppression for enhanced monitoring of 3D bioprinted tissues and vascular-like networks

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Journal of Innovative Optical Health Sciences 2024年第6期17卷 67-82页

作者： Shanshan Yang Jinhao Zhou Hao guo Ling Wang Mingen Xu Hangzhou Dianzi University Automation College HangzhouZhejiangP.R.China Zhejiang Provincial Key Laboratory of Medical Information and Biological 3D Printing Hangzhou ZhejiangP.R.China

Optical coherence tomography(OCT)imaging technology has significant advantages in in situ and noninvasive monitoring of biological ***,it still faces the following challenges:including data processing speed,image quality,and improvements in three-dimensional(3D)visualization *** technology,especially functional imaging techniques like optical coherence tomography angiography(OCTA),requires a long acquisition time and a large data *** the substantial increase in the acquisition speed of swept source optical coherence tomography(SS-OCT),it still poses significant challenges for data ***,during in situ acquisition,image artifacts resulting from interface reflections or strong reflections from biological tissues and culturing containers present obstacles to data visualization and further ***,a customized frequency domainfilter with anti-banding suppression parameters was designed to suppress artifact ***,this study proposed a graphics processing unit(GPU)-based real-time data processing pipeline for SS-OCT,achieving a measured line-process rate of 800 kHz for 3D fast and high-quality data ***,a GPU-based realtime data processing for CC-OCTA was integrated to acquire dynamic ***,a vascular-like network chip was prepared using extrusion-based 3D printing and sacrificial materials,with sacrificial material being printed at the desired vascular network locations and then removed to form the vascular-like *** imaging technology was used to monitor the progression of sacrificial material removal and vascular-like network ***,GPU-based OCT enables real-time processing and visualization with artifact suppression,making it particularly suitable for in situ noninvasive longitudinal monitoring of 3D bioprinting tissue and vascular-like networks in microfluidic chips.

关键词： SS-OCT GPU acceleration artifact noise 3D bioprinted microfluidic chip.

Model-free Speed Control of Single-phase Flux Switching Motor with an Asymmetrical Rotor

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CES Transactions on Electrical Machines and Systems 2024年第3期 255-263页

作者： Zongsheng Zhang Congcong guo School of Electrical Engineering and automation Shandong University of Science and Technology Qingdao Technical college

This paper proposes and implements a model-free open-loop iterative learning control(ILC) strategy to realize the speed control of the single-phase flux switching motor(FSM) with an asymmetrical rotor. Base on the proposed winding control method, the asymmetrical rotor enables the motor to generate continuous positive torque for positive rotation, and relatively small resistance torque for negative rotation. An initial iteration coefficient and variable iteration coefficient optimized scheme was proposed based on the characteristics of the hardware circuit, thereby forming the model-free strategy. A series of prototype experiments was carried out. Experimental results verify the effectiveness and practicability of the proposed ILC strategy.

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Event-triggered impulsive synchronization of heterogeneous neural networks

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Science China(Information Sciences) 2024年第2期67卷 331-332页

作者： Zhengxin WANG Chongfang JIN Wangli HE Min XIAO guo-Ping JIANG Jinde CAO college of Science Nanjing University of Posts and Telecommunications Jiangsu Engineering Lab for IOT Intelligent Robots (IOTRobot) Nanjing University of Posts and Telecommunications Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and Technology School of automation Nanjing University of Posts and Telecommunications School of Mathematics Southeast University Yonsei Frontier Lab Yonsei University

Synchronization is one of the most important dynamics in neural networks. Several scholars have studied the quasi-synchronization of heterogeneous neural networks [1],wherein external controllers play a significant role. Impulsive control, a kind of energy-saving control, is activated instantaneously only at specific discrete moments.

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Integrated intelligent control analysis on semi-active structures by using magnetorheological dampers

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Science China(Technological Sciences) 2008年第12期51卷 2270-2284页

作者： XU ZhaoDong1 & guo YingQing2 1Civil Engineering college, Southeast University, Nanjing 210096, China 2 automation college, Southeast University, Nanjing 210096, China Civil Engineering college Southeast University automation college Southeast University

The control strategy is very important for semiactive control or active control systems. An integrated intelligent control strategy for building structures incorpo rated with magnetorheological (MR) dampers subjected to earthquake excitation is proposed. In this strategy, the time-delay problem is solved by a neural network and the control currents of the MR dampers are determined quickly by a fuzzy controller. Through a numerical example of a three-storey structure with one MR damper installed in the first floor, the seismic responses of the uncontrolled, the intelligently controlled, the passiveon controlled, and the passive-off controlled structures under different earthquake excitations are analyzed. Based on the numerical results, it can be found that the time domain and the frequency domain responses are reduced effectively when the MR damper is added in the structure, and the integrated intelligent control strategy has a better earthquake mitigation effect.

关键词： magnetorheological damper semi-active control intelligent

Artificial neural network-based method for discriminating Compton scattering events in high-purity germaniumγ-ray spectrometer

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Nuclear Science and Techniques 2024年第2期35卷 64-84页

作者： Chun-Di Fan guo-Qiang Zeng Hao-Wen Deng Lei Yan Jian Yang Chuan-Hao Hu Song Qing Yang Hou college of Nuclear Technology and automation Engineering Chengdu University of TechnologyChengdu 610059China

To detect radioactive substances with low activity levels,an anticoincidence detector and a high-purity germanium(HPGe)detector are typically used simultaneously to suppress Compton scattering background,thereby resulting in an extremely low detection limit and improving the measurement ***,the complex and expensive hardware required does not facilitate the application or promotion of this ***,a method is proposed in this study to discriminate the digital waveform of pulse signals output using an HPGe detector,whereby Compton scattering background is suppressed and a low minimum detectable activity(MDA)is achieved without using an expensive and complex anticoincidence detector and *** electric-field-strength and energy-deposition distributions of the detector are simulated to determine the relationship between pulse shape and energy-deposition location,as well as the characteristics of energy-deposition distributions for fulland partial-energy deposition *** relationship is used to develop a pulse-shape-discrimination algorithm based on an artificial neural network for pulse-feature *** accurately determine the relationship between the deposited energy of gamma(γ)rays in the detector and the deposition location,we extract four shape parameters from the pulse signals output by the *** learning is used to input the four shape parameters into the ***,the pulse signals are identified and classified to discriminate between partial-and full-energy deposition *** partial-energy deposition events are removed to suppress Compton *** proposed method effectively decreases the MDA of an HPGeγ-energy dispersive *** results show that the Compton suppression factors for energy spectra obtained from measurements on ^(152)Eu,^(137)Cs,and ^(60)Co radioactive sources are 1.13(344 keV),1.11(662 keV),and 1.08(1332 keV),respectively,and that the corresponding MDAs are 1.4%,5.

关键词： High-purity germaniumγ-ray spectrometer Pulse-shape discrimination Compton scattering Artificial neural network Minimum detectable activity

Anti-asynchrony output regulation for switched systems under switching-Q-learning event-triggering against DoS attacks

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Science China(Information Sciences) 2024年

作者： Lili LI Yalin CHEN Dan MA Qingjun guo college of Marine Electrical Engineering Dalian Maritime University State Key Laboratory of Synthetical automation for Process Industries Northeastern University college of Information Science and Engineering Northeastern University

This paper proposes a secure output regulation (SOR) scheme for network switched systems(NSSs) experiencing severely unstable dynamics (SUDs). This scheme aims to address the complex consecutive asynchrony caused by long-duration denial-of-service (LDDoS) attacks. When the denial-of-service(DoS) attack lasts longer than the dwell time of each subsystem, switching to a new subsystem is necessary to manage the unstable dynamic behavior caused by SUDs. The controller cannot immediately obtain information about the new modality. However, owing to the delayed access to new modality information by the controller, consecutive asynchrony occurs. To tackle this, we propose a resilient switching rule that mitigates the impact of consecutive asynchrony by choosing the optimal subsystem once the minimum dwell time is met. Multi-stage event-triggering mechanisms (METMs) are proposed to coordinate with switching signals by incorporating modality matching conditions and a switching-Q-learning algorithm. These mechanisms reduce asynchronous durations by aligning modality matching conditions and terminating attacks using attack parameters. This control scheme for SOR of NSSs with SUDs disturbed by LDDoS attacks provides a detailed analysis of dynamic switching behavior, leveraging the resilient switching rule and METMs. Finally,the feasibility of the proposed methodology is substantiated through simulations with an F-18 aircraft model.

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