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Accumulated-state-error-based event-triggered sampling scheme and its application to H∞ control of sampled-data systems

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Science China(Information Sciences) 2024年第6期67卷 328-341页

作者： Xian-Ming zhang Qing-Long HAN Bao-Lin zhang Xiaohua GE dawei zhang School of Science Computingand Engineering TechnologiesSwinburne University of Technology College of Automation and Electronic Engineering Qingdao University of Science & Technology School of Mathematics Shandong University

This paper is concerned with event-triggered H∞control of sampled-data systems. Its novelties lie in three aspects:（i） A novel accumulated-state-error-based event-triggered scheme is introduced by comparing the integral of the state error from tk to t with the system state sampled at tk. This condition works well due to the fact that the so-called Zeno behaviour does not occur.（ii） A novel Lyapunov functional is constructed to establish a criterion to ensure some certain H∞performance of the closed-loop system. This Lyapunov functional is dependent on the integral of the state error involved in the event-triggered scheme.（iii） Under the event-triggered sampling scheme, suitable state-feedback controllers can be designed rather than be given a priori. Moreover, a self-triggered implementation of the proposed event-triggered sampling scheme is presented as well. Finally, a batch reactor model and an inverted pendulum system are given to demonstrate the effectiveness of the proposed method.

关键词： event-triggered sampling self-triggered implementation $H_\infty$ control looped-functional

Joint fuzzy background and adaptive foreground model for moving target detection

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Frontiers of Computer Science 2024年第2期18卷 93-106页

作者： dawei zhang Peng WANG Yongfeng DONG Linhao LI Xin LI School of Artificial Intelligence Hebei University of TechnologyTianjin 300401China Lane Department of Computer Science and Electrical Engineering West Virginia UniversityMorgantownWV 26506-6109USA

Moving target detection is one of the most basic tasks in computer *** conventional wisdom,the problem is solved by iterative optimization under either Matrix Decomposition(MD)or Matrix Factorization(MF)*** utilizes foreground information to facilitate background *** uses noise-based weights to fine-tune the *** both noise and foreground information contribute to the recovery of the *** jointly exploit their advantages,inspired by two framework complementary characteristics,we propose to simultaneously exploit the advantages of these two optimizing approaches in a unified framework called Joint Matrix Decomposition and Factorization(JMDF).To improve background extraction,a fuzzy factorization is *** fuzzy membership of the background/foreground association is calculated during the factorization process to distinguish their contributions of both to background *** describe the spatio-temporal continuity of foreground more accurately,we propose to incorporate the first order temporal difference into the group sparsity constraint *** temporal constraint is adjusted *** foreground and the background are jointly estimated through an effective alternate optimization process,and the noise can be modeled with the specific probability *** experimental results of vast real videos illustrate the effectiveness of our *** with the current state-of-the-art technology,our method can usually form the clearer background and extract the more accurate ***-noise experiments show the noise robustness of our method.

关键词： matrixdecomposition matrix factorization generalized sparsity noise modeling

Developing an atmospheric aging evaluation model of acrylic coatings:A semi-supervised machine learning algorithm

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1617-1627页

作者： Yiran Li Zhongheng Fu Xiangyang Yu Zhihui Jin Haiyan Gong Lingwei Ma Xiaogang Li dawei zhang Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China BRI Southeast Asia Network for Corrosion and Protection(MOE) Shunde Innovation School of University of Science and Technology BeijingFoshan 528399China

To study the atmospheric aging of acrylic coatings,a two-year aging exposure experiment was conducted in 13 representative climatic environments in *** atmospheric aging evaluation model of acrylic coatings was developed based on aging data including11 environmental factors from 567 cities.A hybrid method of random forest and Spearman correlation analysis was used to reduce the redundancy and multicollinearity of the data set by dimensionality reduction.A semi-supervised collaborative trained regression model was developed with the environmental factors as input and the low-frequency impedance modulus values of the electrochemical impedance spectra of acrylic coatings in 3.5wt%NaCl solution as *** model improves accuracy compared to supervised learning algorithms model(support vector machines model).The model provides a new method for the rapid evaluation of the aging performance of acrylic coatings,and may also serve as a reference to evaluate the aging performance of other organic coatings.

关键词： acrylic coatings coatings aging atmospheric environment machine learning

Experimental Study of Electrical‑Assisted Nanomachining of Monocrystalline Copper Using Customized Tungsten Tip

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Nanomanufacturing and Metrology 2024年第2期7卷 60-75页

作者： Tao Wang Yanling Tian Zhilai Lu Weijie Wang Zhao zhang Guangwei Zhu Hui Tang dawei zhang Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin 300072China School of Engineering University of WarwickCoventry CV47ALUK State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083China State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006China

As a promising micro/nanofabrication method,electrical-assisted nanomachining has obtained substantial attention due to its high material removal rate and attainable superior surface *** this study,a rectangular wave electrical signal was applied for nanomachining by a customized tungsten *** to the coupling effect between the electric field and mechanical force,the cutting depth of the machined grooves can be *** electrical-assisted groove processing,a depth of 270 nm and an aspect ratio of 0.6 on the copper sample can be *** influence of operation parameters including applied voltage,frequency,duty ratio,normal force and cutting speed on the machining performance was investigated in terms of the groove depth,width,aspect ratio,and surface *** potential machining mechanisms should be a combination of electric field force,nanoscale electric discharge,electric contact thermal effects,possible annealing behavior,and scraping and plowing actions induced by mechanical forces.

关键词： Tip-based nanofabrication Electrical-assisted machining Nanoscale scratching Machining parameters

Asynchronous gain-scheduled control of deepwater drilling riser system with hybrid event-triggered sampling and unreliable communication

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 272-285页

作者： Na PANG dawei zhang Shuqian ZHU School of Mathematics Shandong UniversityJinan250100China

This paper investigates the recoil control of the deepwater drilling riser system with nonlinear tension force and energy-bounded friction force under the circumstances of limited network resources and unreliable *** from the existing linearization modeling method,a triangle-based polytope modeling method is applied to the nonlinear riser *** on the polytope model,to improve resource utilization and accommodate random data loss and communication delay,an asynchronous gain-scheduled control strategy under a hybrid event-triggered scheme is *** asynchronous linear parameter-varying system that blends input delay and impulsive update equation is presented to model the nonlinear networked recoil control system,where the asynchronous deviation bounds of scheduling parameters are *** to the Lyapunov-Krasovskii functional method,some solvable conditions of disturbance attenuation analysis and recoil control design are derived such that the resulting networked system is exponentially mean-square stable with prescribed H∞*** obtained numerical results verified that the proposed nonlinear networked control method can achieve a better recoil response of the riser system with less transmission data compared with the linear control method.

关键词： Riser system Recoil control Asynchronous gain-scheduled control Data loss Event-triggered scheme

Prevention and Treatment of Mycoplasma pneumoniae Requires Long-term Attention

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Infectious Diseases & Immunity 2024年第2期4卷 58-60页

作者： dawei zhang Zhaomin Feng Quanyi Wang Department of Infectious Diseases Fifth Medical Center of Chinese People's Liberation Army(PLA)General HospitalNational Clinical Research Center for Infectious DiseasesBeijing 100039China Beijing Center for Disease Prevention and Control Beijing 100013China Beijing Research Center for Respiratory Infectious Diseases Beijing 100013China.

Mycoplasma pneumoniae is a major etiological agent of communityacquired pneumonia that accounts for 10%to 40%of communityacquired pneumonia and exhibits distinct cyclic epidemic patterns that recur at 3-to 7-year intervals,[1-4] Nonpharmaceutical interventions(NPIs)against coronavirus disease 2019(COVID-19)that were used by countries worldwide during the pandemic significantly reduced the prevalence of ***.[5]After the lifting of COVID-19 pandemic restrictions,*** gradually grew globally.[6]To provide a better understanding of the growth of *** in 2023,we explored the hazards,incidence,diagnosis,and antibiotic resistance of ***.

关键词： diagnosis pneumoniae lifting

Solid-state non-volatile memories based on vdW heterostructure-based vertical-transport ferroelectric field-effect transistors

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Science China(Information Sciences) 2024年第6期67卷 198-206页

作者： Qiyu YANG Zheng-Dong LUO Fei XIAO Junpeng zhang dawei zhang Dongxin TAN Xuetao GAN Yan LIU Zhufei CHU Yinshui XIA Genquan HAN Hangzhou Institute of Technology Xidian University State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology School of MicroelectronicsXidian University School of Artificial Intelligence Xidian University School of Materials Science and Engineering University of New South Wales (UNSW) Sydney ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET) University of New South Wales (UNSW) Sydney Key Laboratory of Light Field Manipulation and Information Acquisition Ministry of Industry and Information Technologyand Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical University Faculty of Electrical Engineering and Computer Science Ningbo University

Driven by the explosive development of data-centric computation applications, it is becoming urgent to develop in-memory computing devices that are beyond the von Neumann architecture with an arrangement of separated logic and memory components. The transistor-type solid-state non-volatile memories,such as ferroelectric field-effect transistors(Fe FETs), have long been regarded as a competitive candidate for future in-memory computing architectures. However, the density scaling towards high-density arrays would require advanced Fe FETs with reduced footprints, which remains a great challenge so far. Here, a vertical-transport(VT) Fe FET that flips the charge transport channel perpendicular to the substrate plane is proposed, in which a ferroelectric gate and a van der Waals(vd W) heterojunction channel are vertically integrated, effectively reducing the device footprints. The proposed VT-Fe FET shows not only the robust binary non-volatile memory states but also several key synaptic functionalities at the device level. An artificial neural network with supervised learning was simulated based on the device conductance switching properties,showing excellent classification accuracy for the MNIST handwritten digits. These findings suggest that the proposed VT-Fe FET could offer a new solution for future non-volatile memories as well as more advanced neuromorphic systems.

关键词： vdW heterostructure non-volatile memory vertical-transport transistor ferroelectric field-effect transistor memristive devices

Microbiologically influenced corrosion resistance enhancement of coppercontaining high entropy alloy Fe_(x)Cu_(1−x)CoNiCrMn against Pseudomonas aeruginosa

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International Journal of Minerals,Metallurgy and Materials 2024年第11期31卷 2488-2497页

作者： Yuntian Lou Weiwei Chang Yu zhang Shengyu He Xudong Chen Hongchang Qian dawei zhang Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China BRI Southeast Asia Network for Corrosion and Protection(MOE) Shunde Innovation SchoolUniversity of Science and Technology BeijingFoshan 528399China School of Materials Science and Energy Foshan UniversityFoshan 528000China

To enhance the microbiologically influenced corrosion(MIC)resistance of FeCoNiCrMn high entropy alloy(HEAs),a series of Fe_(x)Cu_((1−x))CoNiCrMn(x=1,0.75,0.5,and 0.25)HEAs were *** characteristics,corrosion behavior(morphology observation and electrochemical properties),and antimicrobial performance of Fe_(x)Cu_((1−x))CoNiCrMn HEAs were evaluated in a medium inoculated with typical corrosive microorganism Pseudomonas *** aim was to identify copper-containing FeCoNiCrMn HEAs that balance corrosion resistance and antimicrobial *** revealed that all Fe_(x)Cu_((1−x))CoNiCrMn(x=1,0.75,0.5,and 0.25)HEAs exhibited an FCC(face centered cubic)phase,with significant grain refinement observed in Fe_(0.75)Cu_(0.25)CoNiCrMn *** tests indicated that Fe_(0.75)Cu_(0.25)CoNiCrMn HEA demonstrated lower corrosion current density(i_(corr))and pitting potential(E_(pit))compared to other Fe_(x)Cu_((1−x))CoNiCrMn HEAs in ***-inoculated medium,exhibiting superior resistance to ***-microbial tests showed that after 14 d of immersion,Fe_(0.75)Cu_(0.25)CoNiCrMn achieved an antibacterial rate of 89.5%,effectively inhibiting the adhesion and biofilm formation of ***,thereby achieving resistance to MIC.

关键词： microbiologically influenced corrosion Pseudomonas aeruginosa high entropy alloys antibacterial property

3D nano-printed geometric phase metasurfaces for generating accelerating beams with complex amplitude manipulation

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 86-95页

作者： Tianchen Tang Saima Kanwal Yongzheng Lu Yuelong Li Shuangbao Wu Lei Chen Ziheng Qian Zhouyu Xie Jing Wen dawei zhang Research Center of Optical Instrument and System Ministry of Education and Shanghai Key Lab of Modern Optical SystemUniversity of Shanghai for Science and TechnologyShanghai 200093China

Metasurface,a forefront in emerging optical devices,has demonstrated remarkable potential for complex amplitude manipulation of light ***,prevailing approaches face challenges in spatial resolution and complexities associated with integrating dynamic phases,impeding the simplified design and reproducible fabrication of ***,we introduce an innovative approach for complex amplitude modulation within 3D nano-printed geometric phase *** approach enables the generation of self-accelerating beams by encoding amplitude through phase-only manipulation,achieving high spatial ***,this method circumvents the conventional need to adjust the geometric parameters of metasurface unit structures for amplitude manipulation,offering a streamlined and efficient route for design and fabrication *** novel methodology holds promise for expedited and low-cost manufacturing of complex amplitude manipulation metasurfaces.

关键词： metasurface complex amplitude manipulation geometric phase 3D nano-printing Airy beam accelerating parabolic beam