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A method for establishing a bearing residual life prediction model for process enhancement equipment based on rotor imbalance response analysis

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Chinese Journal of Chemical engineering 2024年第2期66卷 203-215页

作者： Feng Wang Haoran Li Zhenghui Zhang Yan Bai Hong Yin Jing Bian national Foundation research Laboratory of Fault Prevention and control in Hazardous Chemicals Production system Engineering Research Center of Chemical Technology SafetyBeijing University of Chemical TechnologyBeijing 100029China China Nuclear Power engineering Co. LtdBeijing 100840China CNOOC Tianjin Chemical research and Design Institute Co. LtdTianjin Key Laboratory of Energy and Chemical Explosion SafetyAcademician Expert Collaborative Innovation CenterTianjin 300131China

A rotating packed bed is a typical chemical process enhancement equipment that can strengthen micromixing and mass *** the operation of the rotating packed bed,the nonreactants and products irregularly adhere to the wire mesh packing in the rotor,thus resulting in an imbalance in the vibration of the rotor,which may cause serious damage to the bearing and material *** study proposes a model prediction for estimating the bearing residual life of a rotating packed bed based on rotor imbalance response *** method is used to determine the influence of the mass on the imbalance in the vibration of the rotor on bearing *** major influence on rotor vibration was found to be exerted by the imbalanced mass and its distribution radius,as revealed by the results of orthogonal *** implementing finite element analysis,the imbalance response curve for the rotating packed bed rotor was obtained,and a correlation among rotor imbalance mass,distribution radius of imbalance mass,and bearing residue life was established via data *** predicted value of the bearing life can be used as the reference basis for an early safety warning of a rotating packed bed to effectively avoid accidents.

关键词： Rotating packed bed Mass imbalance Harmonic response analysis Residual life Prediction model

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An Improved Method for Approximating the Infinite-Horizon Value Function of the Discrete-Time Switched LQR Problem

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Journal of systems Science & Complexity 2024年第1期37卷 22-39页

作者： HOU Tan LI Yuanlong LIN Zongli Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of system control and Information Processing Ministry of Education of ChinaShanghai 200240China Shanghai engineering research center of Intelligent control and Management Shanghai 200240China Charles L.Brown Department of Electrical and Computer engineering University of VirginiaCharlottesvilleVA 22904-4743USA

This paper considers the problem of approximating the infinite-horizon value function of the discrete-time switched LQR *** particular,the authors propose a new value iteration method to generate a sequence of monotonically decreasing functions that converges exponentially to the value *** method facilitates us to use coarse approximations resulting from faster but less accurate algorithms for further value iteration,and thus,the proposed approach is capable of achieving a better approximation for a given computation time compared with the existing *** numerical examples are presented in this paper to illustrate the effectiveness of the proposed method.

关键词： Optimal control switched linear systems switched LQR problem.

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Chromosome-level genome assembly of the Asian citrus psyllid,Diaphorina citri

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Insect Science 2024年第1期31卷 13-27页

作者： Shuang Lei Shi-Jiang Yu Qi Pan Li-Li Ding Si-Chen Li Lu-Yan Cheng Shu-Qi Wang Bing-Hai Lou Jun He Cui-Yun Lei Lin Cong Hao-Qiang Liu Xue-Feng Wang Chun Ran Citrus research Institute Southwest University/Chinese Academy of Agricultural SciencesNational Engineering Research Center for CitrusChongqingChina

Diaphorina citri is a global citrus *** a vector insect,it can transmit the causative agents of citrus huanglongbing,causing irreversible losses to the citrus *** acquisition of genomic information can provide a molecular genetic basis for effective control of ***,the DNBSEQ™,Oxford Nanopore Technologies,and Hi-C technologies are applied to generate a high-quality chromosome-level genome of *** genome size of *** was 523.78 Mb with a scaffold N50 of 47.05 Mb distributed on 13 chromosomes.A total of 250.64 Mb(47.85%)repeat sequences and 24048 protein-coding genes were *** resequencing of female and male individuals indicated that the sex chromosome system of *** is *** analysis demonstrated that *** and Pachypsylla venusta,which separated from their most recent common ancestor about 336.62 million years ago,were the most closely ***,we identified genes potentially involved in detoxification metabolism,pathogen transmission,and honeydew secretion for further *** high-quality genome provides an important reference for developing effective management strategies of ***.

关键词： Asian citrus psyllid chromosome-level genome comparative genomics cytochrome P450 detoxification Huanglongbing

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Simultaneous removal of Cd(Ⅱ)and As(Ⅴ)by ferrihydrite-biochar composite:Enhanced effects of As(Ⅴ)on Cd(Ⅱ)adsorption

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Journal of Environmental Sciences 2024年第5期139卷 267-280页

作者： Wenjun Zeng Yang Lu Jingyan Zhou Jie Zhang Yuanxiao Duan Changxun Dong Wencheng Wu College of Sciences Nanjing Agricultural UniversityNanjing 210095China South China Institute of Environmental Sciences Ministry of Ecology and EnvironmentGuangzhou 510655China Guangdong engineering&Technology research center for system control of Livestock and Poultry breeding Pollution Guangzhou 510655China

The coexistence of cadmium(Cd(Ⅱ))and arsenate(As(Ⅴ))pollution has long been an environmental ***,a porous carbonaceous material with tunable functionality,has been used for the remediation of contaminated ***,it is still challenging for the dynamic quantification and mechanistic understanding of the simultaneous sequestration of multi-metals in biochar-engineered environment,especially in the presence of *** this study,ferrihydrite was coprecipitated with biochar to investigate how ferrihydritebiochar composite affects the fate of heavy metals,especially in the coexistence of Cd(Ⅱ)and As(Ⅴ).In the solution system containing both Cd(Ⅱ)and As(Ⅴ),the maximum adsorption capacities of ferrihydrite-biochar composite for Cd(Ⅱ)and As(Ⅴ)reached 82.03μmol/g and 531.53μmol/g,respectively,much higher than those of the pure biochar(26.90μmol/g for Cd(Ⅱ),and 40.24μmol/g for As(Ⅴ))and ferrihydrite(42.26μmol/g for Cd(Ⅱ),and 248.25μmol/g for As(Ⅴ)).Cd(Ⅱ)adsorption increased in the presence of As(Ⅴ),possibly due to the changes in composite surface charge in the presence of As(Ⅴ),and the increased dispersion of ferrihydrite by *** microscopic and mechanistic results showed that Cd(Ⅱ)complexed with both biochar and ferrihydrite,while As(Ⅴ)was mainly complexed by ferrihydrite in the Cd(Ⅱ)and As(Ⅴ)coexistence *** posed vital importance for the co-adsorption of Cd(Ⅱ)and As(Ⅴ).The different distribution patterns revealed by this study help to a deeper understanding of the behaviors of cations and anions in the natural environment.

关键词： Ferrihydrite Biochar Cadmium Arsenate Simultaneous sequestration Binding mechanisms

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Cognitive Navigation for Intelligent Mobile Robots:A Learning-Based Approach With Topological Memory Configuration

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 1933-1943页

作者： Qiming Liu Xinru Cui Zhe Liu Hesheng Wang Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China MoE Key Laboratory of Artificial Intelligence AI InstituteShanghai Jiao Tong UniversityShanghai 200240China Department of Automation Key Laboratory of System Control and Information Processing of Ministry of EducationKey Laboratory of Marine Intelligent Equipment and System of Ministry of EducationShanghai Engineering Research Center of Intelligent Control and ManagementShanghai Jiao Tong UniversityShanghai 200240China

Autonomous navigation for intelligent mobile robots has gained significant attention,with a focus on enabling robots to generate reliable policies based on maintenance of spatial *** this paper,we propose a learning-based visual navigation pipeline that uses topological maps as memory *** introduce a unique online topology construction approach that fuses odometry pose estimation and perceptual similarity *** tackles the issues of topological node redundancy and incorrect edge connections,which stem from the distribution gap between the spatial and perceptual ***,we propose a differentiable graph extraction structure,the topology multi-factor transformer(TMFT).This structure utilizes graph neural networks to integrate global memory and incorporates a multi-factor attention mechanism to underscore elements closely related to relevant target cues for policy *** from photorealistic simulations on image-goal navigation tasks highlight the superior navigation performance of our proposed pipeline compared to existing memory *** validation through behavior visualization,interpretability tests,and real-world deployment further underscore the adapt-ability and efficacy of our method.

关键词： Graph neural networks(GNNs) spatial memory topological map visual navigation

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State and parameter identification of linearized water wave equation via adjoint method

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Science China(Information Sciences) 2024年第10期67卷 283-297页

作者： Yang YU Cheng-Zhong XU Hai-Long PEI Jinpeng YU School of Automation Qingdao University LAGEP Batiment CPE University Claude Bernard-Lyon 1 School of Automation Science and engineering Key Laboratory of Autonomous Systems and Networked ControlMinistry of Education Guangdong Engineering Technology Research Center of Unmanned Aerial Vehicle SystemSouth China University of Technology

In this paper, we focus on the state and parameter identification problem of a hydrodynamical system. This system is modeled as a linearized water wave equation(LWWE), a hyperbolic state-space model coupled with a Laplace equation. We assume that the wave elevation at two distinct points is the only measurement of water waves. We show that the state and water depth can be reconstructed from this point measurement records. The identification problem is recast as an optimization problem over an infinite-dimensional space. We propose the adjoint method-based identification algorithm to generate an estimated state and water depth. We then performed a numerical simulation to show the effectiveness of our designed algorithm by comparing it with existing studies.

关键词： linearized water wave equation (LWWE) point observation state estimation parameter identification adjoint method numerical simulation

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Force Compensation control for Electro-Hydraulic Servo system with Pump-Valve Compound Drive via QFT-DTOC

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Chinese Journal of Mechanical engineering 2024年第2期37卷 228-246页

作者： Kaixian Ba Yuan Wang Xiaolong He Chunyu Wang Bin Yu Yaliang Liu Xiangdong Kong Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and control Qinhuangdao 066004China School of Mechanical engineering Yanshan UniversityQinhuangdao 066004China national engineering research center for Local Joint of Advanced Manufacturing Technology and Equipment Yanshan UniversityQinhuangdao 066004China

Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ***,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy *** contrast,pump control systems offer a high ***,their response ability is *** fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(PCDS)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of ***,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the PCDS force control system is first *** addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC *** method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the ***,experimental verification is performed using the PCDS performance test *** experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the *** relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot.

关键词： Legged robot Pump-valve compound drive system(PCDS) Force compensation control Quantitative feedback theory(QFT) Disturbance torque observer(DTO)

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Synergistic effects of peroxydisulfate on UV/O3 process for tetracycline degradation:Mechanism and pathways

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Chinese Chemical Letters 2024年第10期35卷 434-439页

作者： Fengrui Yang Debing Wang Xinying Zhang Jie Zhang Zhichao Wu Qiaoying Wang State Key Laboratory of Pollution control and Resource Reuse Shanghai Institute of Pollution Control and Ecological Security School of Environmental Science and Engineering Tongji University Fujian Provincial engineering research center of Rural Waste Recycling Technology College of Environment & Safety Engineering Fuzhou University

Tetracycline（TC） as a typical emerging pollutant is becoming a serious threat to the environment and human health. A combined advanced oxidation technology of UV/Ozone（O3）/peroxydisulfate（PDS） process was developed to explore an efficient and economic treatment process of TC in wastewater. Furthermore,the reactive sites and transformation pathways of TC were explored and the toxicity of the intermediates was quantified with a quantitative structure-activity relationship（QSAR） assessment. The degradation performance of TC was substantially enhanced in UV/O3/PDS process with a kobsof 0.0949 min-1,which was 2.3 times higher than UV/O3and 3.2 times than sole UV. The results demonstrated that there was a superior synergistic effect of PDS on UV/O3processes for the degradation of TC. Electron paramagnetic resonance（EPR） analysis and quenching experiments show that·OH, SO4·-, O2·-and1O2all contributed to TC degradation in the UV/O3/PDS process and exhibited a synergistic effect, which inhibited the generation of harmful products. In addition, the UV/O3/PDS system can effectively degrade TC in a wide range of substrate concentrations and pH, and also showed excellent adaptability to various concentrations of anions（Cl-and HCO3-）. This study proves the feasibility of UV/O3/PDS process for treating TC contaminated wastewater with complicated water matrix.

关键词： Degradation Synergistic effect Tetracycline UV/ozonation/peroxydisulfate Wastewater

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Exploring Antarctic subglacial lakes with RECoverable Autonomous Sonde(RECAS):Design and first field tests

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Science China(Technological Sciences) 2024年第6期67卷 1866-1878页

作者： SUN YouHong PAVEL Talalay LI YuanSheng YU HaiBin WANG DongLiang LI GuoPing XU LiPing GONG Da WANG JiXin WANG JianHua WANG Ting ZHANG Nan WANG ZhiGang CHEN YanJi LIU YunChen LI YaZhou PENG ShiLin SHI JianGuang AN ChunLei GE Qun XU Jing NI XiaoKang CUI QiFeng JIANG Qiang MIKHAIL Sysoev Yang Yang WANG RuSheng WEI XianZhe WANG Yu ZHU TianXin DENG ZhiPeng ALEXEY Markov LI Bing FAN XiaoPeng Polar research center Jilin UniversityChangchun130000China School of engineering and Technology China University of GeosciencesBeijing100083China Polar research Institute of China Shanghai200120China College of Electronics and Information Hangzhou Dianzi UniversityHangzhou310018China Aerospace system engineering Shanghai Shanghai201109China Nanjing Institute of Astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing210000China national Ocean Technology center Tianjin300000China

Conducting scientific drilling on subglacial lakes and obtaining samples of subglacial lake water holds great significance in unraveling the formation and evolution of Antarctic subglacial lakes and early Earth's life *** various approaches to access and directly sample subglacial water and sediments,clean access and exploration of subglacial lakes remain *** address this concern,Jilin University has developed the RECoverable Autonomous Sonde(RECAS)*** technology enables sampling and in-situ detection of subglacial lake water while being isolated from the surface,thus minimizing the risk of *** tests,including downward and upward drilling,long-running,remote-control,and cold-environment assessments,were conducted to validate the sonde's principle and *** the 38th Chinese national Antarctic research Expedition,CHINARE(2021–2022 season),the RECAS prototype underwent testing on the flank region of Dalk glacier,10 km from Zhongshan Station in *** boreholes with depths of 200.3,183.2,and 133.5 m were successfully drilled,with the refrozen meltwater sealing the boreholes during the *** 600 mL of melted water samples were collected from each *** the drilling tests,all systems of the RECAS prototype performed within the expected ranges.

关键词： subglacial lake thermal drilling water sampling Antarctic autonomous sonde

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A model reduction approach for discrete-time linear time-variant systems with delayed inputs

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Science China(Information Sciences) 2024年第4期67卷 197-217页

作者： Ai-Guo WU Guang-Ren DUAN Yu WANG Jie ZHANG School of Mechanical engineering and Automation Harbin Institute of Technology(Shenzhen) HIT Wuhu Robot Technology research Institute center for control Science and Technology Southern University of Science and Technology

A model reduction approach is presented for discrete-time linear time-variant input-delayed systems. According to this proposed approach, a dynamical variable is constructed by taking advantage of the current state and historical information of input. It is revealed that the behavior of this dynamical variable is governed by a discrete-time linear delay-free system. It is worth noting that the presented variable transformation does not require the system matrix to be invertible. Based on the reduced delay-free models,stabilizing control laws can be easily obtained for the original delayed system. For the case with a single input delay, the constructed variable is an exact prediction for the future state, and thus the stabilizing control law could be designed by replacing the future state with its prediction. Finally, three discrete-time periodic systems with delayed input are employed to illustrate how to utilize the presented model reduction approaches.

关键词： reduction approach predictor-based feedback time-varying systems delayed input periodic system

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