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control Theory and Technology 2024年第1期22卷 69-80页

作者： Junqi Yang Jianhao Xie Feiyang Liu School of Electrical engineering and Automation Henan Key Laboratory of Intelligent Detection and Control of Coal Mine EquipmentHenan Polytechnic UniversityJiaozuo454003HenanChina

For a class of time-delay discrete-time linear systems with external disturbance and measurement noise, the interval estimation problems of state and measurement noise are investigated in this paper. First, the system state together with the time-delay term and measurement noise is augmented as a new state, and a singular system is then constructed. Subsequently, a kind of decoupling technique is employed to eliminate the effect of external disturbance, and an observer is designed to simultaneously estimate the system state and measurement noise. Based on the estimated state and measurement noise, the interval estimations of system state and measurement noise are obtained by reachability analysis technique. Finally, the effectiveness of the proposed method is verified by a four-tank liquid level system.

关键词： Interval estimation Time-delay system Observer design Reachability analysis

Theoretical insights of the pharmaceutical compound fluoxetine in water:Role in direct photolysis and indirect photolysis by free radicals

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Journal of Environmental Sciences 2024年第8期142卷 269-278页

作者： Ying Lu Se Wang Yifan Shen School of Environmental Science and engineering Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologyJiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution ControlNanjing University of Information Science and TechnologyNanjing 210044China

The frequent detection of pharmaceutical compounds in the environment has led to a growing awareness,which may pose a major threat to the aquatic *** this study,photodegradation(direct and indirect photolysis)of two different dissociation states of fluoxetine(FLU)was investigated in water,mainly including the determination of photolytic transition states and products,and the mechanisms of indirect photodegradation with·OH,CO_(3)^(*-)and NO_(3)^(*).The main direct photolysis pathways are defluorination and C–C bond *** addition,the indirect photodegradation of FLU in water is mainly through the reactions with·OH and NO_(3)^(*),and the photodegradation reaction with CO_(3)^(*-)is relatively difficult to occur in the water *** results provide a theoretical basis for understanding the phototransformation process of FLU in the water environment and assessing its potential risk.

关键词： Fluoxetine Photochemical mechanism Direct photolysis Free radical reaction DFT

Aeroengine thrust estimation and embedded verification based on improved temporal convolutional network

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Chinese Journal of Aeronautics 2024年第1期37卷 106-117页

作者： Wanzhi MENG Zhuorui PAN Sixin WEN Pan QIN Ximing SUN key laboratory of Intelligent control and Optimization for Industrial equipment of Ministry of Education Dalian University of TechnologyDalian 116024China School of control Science and engineering Dalian University of TechnologyDalian 116024China

Thrust estimation is a significant part of aeroengine thrust control *** traditional estimation methods are either low in accuracy or large in *** further improve the estimation effect,a thrust estimator based on Multi-layer Residual Temporal Convolutional Network(M-RTCN)is *** solve the problem of dead Rectified Linear Unit(ReLU),the proposed method uses the Gaussian Error Linear Unit(GELU)activation function instead of ReLU in residual *** the overall architecture of the multi-layer convolutional network is adjusted by using residual connections,so that the network thrust estimation effect and memory consumption are further ***,the comparison with seven other methods shows that the proposed method has the advantages of higher estimation accuracy and faster convergence ***,six neural network models are deployed in the embedded controller of the micro-turbojet *** Hardware-in-the-Loop(HIL)testing results demonstrate the superiority of M-RTCN in terms of estimation accuracy,memory occupation and running ***,an ignition verification is conducted to confirm the expected thrust estimation and real-time performance.

关键词： Thrust estimation Temporal convolutional network Embedded deployment Hardware-in-the-loop testing Ignition verification

An electromagnetic semi-active dynamic vibration absorber for thin-walled workpiece vibration suppression in mirror milling

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1315-1334页

作者： Jianghua KONG Bei DING Wei WANG Zhixia WANG Juliang XIAO Hongyun QIU School of Mechanical engineering Tianjin University Tianjin key laboratory of Nonlinear Dynamics and control key laboratory of Modern Mechanisms and equipment Design of the State Ministry of Education Tianjin University

As critical components of aircraft skins and rocket fuel storage tank shells,large thin-walled workpieces are susceptible to vibration and deformation during machining due to their weak local stiffness. To address these challenges, we propose a novel tunable electromagnetic semi-active dynamic vibration absorber(ESADVA), which integrates with a magnetic suction follower to form a followed ESADVA(follow-ESADVA)for mirror milling. This system combines a tunable magnet oscillator with a follower,enabling real-time vibration absorption and condition feedback throughout the milling process. Additionally, the device supports self-sensing and frequency adjustment by providing feedback to a linear actuator, which alters the distance between magnets. This resolves the traditional issue of being unable to directly monitor vibration at the machining point due to space constraints and tool interference. The frequency shift characteristics and vibration absorption performance are comprehensively investigated. Theoretical and experimental results demonstrate that the prototyped follow-ESADVA achieves frequency synchronization with the milling tool, resulting in a vibration suppression rate of approximately 47.57%. Moreover, the roughness of the machined surface decreases by18.95%, significantly enhancing the surface quality. The results of this work pave the way for higher-quality machined surfaces and a more stable mirror milling process.

关键词： 70J35 mirror milling O326 self-sensing semi-active dynamic vibration absorber (SADVA) thin-walled workpiece vibration absorption tuning

controlled thermally-driven mass transport in carbon nanotubes using carbon hoops

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Chinese Physics B 2024年第4期33卷 66-69页

作者：李耀隆李松远王美芬张任良 Hebei key laboratory of Mechanical Reliability for Heavy equipment and large Structures Yanshan UniversityQinhuangdao 066004China School of Civil engineering and Mechanics Yanshan UniversityQinhuangdao 066004China

controlling mass transportation using intrinsic mechanisms is a challenging topic in ***,we employ molecular dynamics simulations to investigate the mass transport inside carbon nanotubes(CNT)with temperature gradients,specifically the effects of adding a static carbon hoop to the outside of a CNT on the transport of a nanomotor inside the *** reveal that the underlying mechanism is the uneven potential energy created by the hoops,i.e.,the hoop outside the CNT forms potential energy barriers or wells that affect mass transport inside the *** fundamental control of directional mass transportation may lead to promising routes for nanoscale actuation and energy conversion.

关键词： molecular dynamics thermal drive nanotube hoop mass transport

An anonymous authentication and secure data transmission scheme for the Internet of Things based on blockchain

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Frontiers of Computer Science 2024年第3期18卷 183-197页

作者： Xingxing CHEN Qingfeng CHENG Weidong YANG Xiangyang LUO State key laboratory of Mathematical engineering and Advanced Computing Zhengzhou Institute of Information Science and TechnologyZhengzhou 450001China Henan key laboratory of Grain Photoelectric detection and control Henan University of TechnologyZhengzhou 450001China Henan Province key laboratory of Cyberspace Situation Awareness Zhengzhou Institute of Information Science and TechnologyZhengzhou 450001China

With the widespread use of network infrastructures such as 5G and low-power wide-area networks,a large number of the Internet of Things(IoT)device nodes are connected to the network,generating massive amounts of ***,it is a great challenge to achieve anonymous authentication of IoT nodes and secure data *** present,blockchain technology is widely used in authentication and s data storage due to its decentralization and ***,Fan et *** a secure and efficient blockchain-based IoT authentication and data sharing *** studied it as one of the state-of-the-art protocols and found that this scheme does not consider the resistance to ephemeral secret compromise attacks and the anonymity of IoT *** overcome these security flaws,this paper proposes an enhanced authentication and data transmission scheme,which is verified by formal security proofs and informal security ***,Scyther is applied to prove the security of the proposed ***,it is demonstrated that the proposed scheme achieves better performance in terms of communication and computational cost compared to other related schemes.

关键词： Internet of Things blockchain authentication data transmission

Arc Grounding Fault Identification Using Integrated Characteristics in the Power Grid

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Energy engineering 2024年第7期121卷 1883-1901页

作者： Penghui Liu Yaning Zhang Yuxing Dai Yanzhou Sun School of Electrical engineering and Automation Henan Polytechnic UniversityJiaozuo454003China Research and Development Center Guangdong Zhicheng Champion Group Co.Ltd.Dongguan523000China Henan key laboratory of Intelligent detection and control of Coal Mine equipment Henan Polytechnic UniversityJiaozuo454003China

Arc grounding faults occur frequently in the power grid with small resistance grounding neutral *** existing arc fault identification technology only uses the fault line signal characteristics to set the identification index,which leads to detection failure when the arc zero-off characteristic is *** solve this problem,this paper presents an arc fault identification method by utilizing integrated signal characteristics of both the fault line and sound ***,the waveform characteristics of the fault line and sound lines under an arc grounding fault are *** that,the convex hull,gradient product,and correlation coefficient index are used as the basic characteristic parameters to establish fault identification ***,the logistic regression algorithm is employed to deal with the reference samples,establish the machine discrimination model,and realize the discrimination of fault ***,simulation test results and experimental results verify the accuracy of the proposed *** comparison analysis shows that the proposed method has higher recognition accuracy,especially when the arc dissipation power is smaller than 2×10^(3) W,the zero-off period is not *** conclusion,the proposed method expands the arc fault identification theory.

关键词： Arc fault convex hull algorithm correlation coefficient fault identification gradient logistic regression

Molecular-level proton acceptor boosts oxygen evolution catalysis to enable efficient industrial-scale water splitting

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Green Energy & Environment 2024年第2期9卷 344-355页

作者： Yaobin Wang Qian Lu Xinlei Ge Feng Li Le Chen Zhihui Zhang Zhengping Fu Yalin Lu Yang Song Yunfei Bu jiangsu Collaborative Innovation Center of Atmospheric Environment and equipment Technology(CICAEET) Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control(AEMPC)UNIST-NUIST Energy and Environment Jointed Lab(UNNU)School of Environmental Science and TechnologyNanjing University of Information Science and Technology(NUIST)219 NingliuNanjing210044China laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan University220 HandanShanghai200433China jiangsu key laboratory of Advanced Materials and Technology School of Petrochemical EngineeringChangzhou University1 GehuChangzhou213164China Anhui laboratory of Advanced Photon Science and Technology University of Science and Technology of China(USTC)96 JinzhaiHefeiAnhui 230026China School of Chemistry and Chemical engineering Nanjing University of Science and Technology200 Xiaolingwei210094China

Industrial water splitting has long been suppressed by the sluggish kinetics of the oxygen evolution reaction(OER),which requires a catalyst to be ***,we propose a molecular-level proton acceptor strategy to produce an efficient OER catalyst that can boost industrial-scale water ***-level phosphate(-PO_(4))group is introduced to modify the surface of PrBa_(0.5)Ca_(0.5)Co_(2)O_(5)+δ(PBCC).The achieved catalyst(PO_(4)-PBCC)exhibits significantly enhanced catalytic performance in alkaline *** on the X-ray absorption spectroscopy results and density functional theory(DFT)calculations,the PO_(4)on the surface,which is regarded as the Lewis base,is the key factor to overcome the kinetic limitation of the proton transfer process during the *** use of the catalyst in a membrane electrode assembly(MEA)is further evaluated for industrial-scale water splitting,and it only needs a low voltage of 1.66 V to achieve a large current density of 1 A cm^(-2).This work provides a new molecular-level strategy to develop highly efficient OER electrocatalysts for industrial applications.

关键词： Oxygen evolution reaction Nanofiber Water splitting Proton acceptor Perovskite

One-pot synthesis of N-doped petroleum coke-based microporous carbon for high-performance CO_(2) adsorption and supercapacitors

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Journal of Environmental Sciences 2024年第5期139卷 93-104页

作者： Wenfu Zhu Yuqin Wang Fan Yao Xiaohong Wang Haoming Zheng Guangzheng Ye Hairong Cheng Junliang Wu Haomin Huang Daiqi Ye School of Environment and Energy South China University of TechnologyGuangzhou 510006China National engineering laboratory for VOCs Pollution control Technology and equipment Guangzhou 510006China Guangdong Provincial key laboratory of Atmospheric Environment and Pollution control(SCUT) Guangzhou 510006China Guangdong Provincial engineering and Technology Research Centre for Environmental Risk Prevention and Emergency Disposal South China University of TechnologyGuangzhou 510006China

Waste resource utilization of petroleum coke is crucial for achieving global carbon emission ***,a series of N-doped microporous carbons were fabricated from petroleum coke using a one-pot synthesis *** as-prepared samples had a large specific surface area(up to 2512 m^(2)/g),a moderate-high N content(up to 4.82 at.%),and high population(55%)of ultra-micropores(<0.7 nm).Regulating the N content and ultra-microporosity led to efficient CO_(2)adsorption and *** ambient pressure,the optimal N-doped petroleum coke-based microporous carbon exhibited the highest CO_(2)uptake of 4.25 mmol/g at 25℃ and 6.57 mmol/g at 0℃.These values are comparable or even better than those of numerous previously reported adsorbents prepared by multistep synthesis,primarily due to the existence of *** sample exhibited excellent CO_(2)/N_(2)selectivity at 25℃ owing to the abundant basic pyridinic and pyrrolic N species;and showed superior CO_(2)adsorption-desorption cycling performance,which was maintained at 97% after 10 cycles at 25℃.Moreover,petroleum coke-based microporous carbon,with a considerably high specific surface area and hierarchical pore structure,exhibited excellent electrochemical performance over the N-doped sample,maintaining a favorable specific capacitance of 233.25F/g at 0.5 A/g in 6 mol/L KOH aqueous *** study provides insight into the influence of N-doping on the porous properties of petroleum coke-based ***,the as-prepared carbons were found to be promising adsorbents for CO_(2)adsorption,CO_(2)/N_(2)separation and electrochemical application.

关键词： One-pot synthesis N-doped microporous carbon CO_(2)adsorption CO_(2)/N_(2)selectivity Electrochemical performance

Real-Time Intelligent Diagnosis of Co-frequency Vibration Faults in Rotating Machinery Based on Lightweight-Convolutional Neural Networks

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Chinese Journal of Mechanical engineering 2024年第2期37卷 264-282页

作者： Xin Pan Xiancheng Zhang Zhinong Jiang Guangfu Bin Beijing key laboratory of Health Monitoring and Self-recovery for High-End Mechanical equipment College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China key laboratory of Engine Health Monitoring-control and Networking(Ministry of Education) College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China College of Mechanical engineering Hunan University of Science and TechnologyXiangtan 411201China

The co-frequency vibration fault is one of the common faults in the operation of rotating equipment,and realizing the real-time diagnosis of the co-frequency vibration fault is of great significance for monitoring the health state and carrying out vibration suppression of the *** engineering scenarios,co-frequency vibration faults are highlighted by rotational frequency and are difficult to identify,and existing intelligent methods require more hardware conditions and are exclusively ***,Lightweight-convolutional neural networks(LW-CNN)algorithm is proposed in this paper to achieve real-time fault *** critical parameters are discussed and verified by simulated and experimental signals for the sliding window data augmentation *** on LW-CNN and data augmentation,the real-time intelligent diagnosis of co-frequency is ***,a real-time detection method of fault diagnosis algorithm is proposed for data acquisition to fault *** is verified by experiments that the LW-CNN and sliding window methods are used with high accuracy and real-time performance.

关键词： Co-frequency vibration Real-time diagnosis LW-CNN Data augmentation