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Control for a Class of Stochastic Mechanical Systems Based on the Discrete-Time Approximate Observer

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Journal of Systems Science & Complexity 2019年第2期32卷 526-541页

作者： FU Xinxin kang yu LI Pengfei yu Peilong Department of Automation University of Science and Technology of China

This paper investigates the observer-based control problem of a class of stochastic mechanical systems. The system is modelled as a continuous-time It o stochastic differential equation with a discrete-time output. Euler-Maruyama approximation is used to design the discrete-time approximate observer, and an observer-based feedback controller is derived such that the closed-loop nonlinear system is exponentially stable in the mean-square sense. Also, the authors analyze the convergence of observer error when the discrete-time approximate observer servers as a state observer for the exact system. Finally, a simulation example is used to demonstrate the effectiveness of the proposed method.

关键词： Approximate model discrete-time observer exponential stability stochastic nonlinear system

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人体微塑料污染特征及健康风险研究进展

环境科学 2024年第1期45卷 459-469页

作者：马敏东赵洋尘朱龙王伟平康玉麟安立会中国环境科学研究院环境基准与风险评估国家重点实验室北京100012 山东省潍坊生态环境监测中心潍坊261061

微塑料污染不仅是一个环境问题,更是一个社会问题.目前针对环境微塑料来源、丰度和分布,已开展了大量研究,但对人体微塑料暴露水平和潜在健康风险的认识仍非常有限.基于文献计量学方法,系统地梳理总结了当前人体微塑料的暴露途径,揭示... 详细信息

微塑料污染不仅是一个环境问题,更是一个社会问题.目前针对环境微塑料来源、丰度和分布,已开展了大量研究,但对人体微塑料暴露水平和潜在健康风险的认识仍非常有限.基于文献计量学方法,系统地梳理总结了当前人体微塑料的暴露途径,揭示了人体微塑料污染的赋存特征及潜在健康危害.结果表明,人体内微塑料主要以粒径小于50μm的聚乙烯(PE)、聚丙烯(PP)、和聚对苯二甲酸乙二醇酯(PET)等人工合成聚合物为主.环境微塑料主要通过食物和呼吸途径进入人体,并在肺部和肠胃组织累积,其中小粒径微塑料可通过循环系统分布于各组织器官.基于实验的毒理学实验结果表明,微塑料不仅影响细胞膜完整性、免疫应激、肠道菌群和能量代谢,对生殖系统也具有潜在危害.为科学评估微塑料污染的健康风险,还需进一步加强微塑料毒理效应及其发生机制研究,构建微塑料健康风险评估框架,以科学依据支撑微塑料污染防治.

关键词：微塑料暴露途径毒理效应分子机制健康风险

FVO: floor vision aided odometry

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Science China(Information Sciences) 2019年第1期62卷 95-107页

作者： Wenjun LV yu kang Jiahu QIN Department of Automation University of Science and Technology of China State Key Laboratory of Fire Science University of Science and Technology of China

In many indoor scenarios, such as restaurants, laboratories, and supermarkets, the planar floors are covered with rectangular tiles. We realized that the abundant parallel lines and crossing points formed by tile joints can be used as natural features to assist indoor localization, and thus we propose a novel indoor localization method for mobile robots by fusing odometry and monocular vision. The method comprises three steps. First, the heading and location of the mobile robot are approximately estimated by odometry based on incremental encoders. Second, with the aid of a camera, the lens of which points vertically toward the floor, the odometric heading estimation can be corrected by detecting the relative angle between the robot’s heading and the tile joints. Third, the odometric location estimation is corrected by detecting the perpendicular distance between the image center and the tile joints. As compared with the existing indoor localization methods, the proposed method, called floor vision aided odometry, is not only relatively low in economic cost and computational complexity, but also relatively high in accuracy and robustness. The effectiveness of this method is verified by a real-world experiment based on a differential-drive wheeled mobile robot.

关键词： mobile robot indoor localization monocular vision odometry tile joint

Self-Tuning Asynchronous Filter for Linear Gaussian System and Applications

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IEEE/CAA Journal of Automatica Sinica 2018年第6期5卷 1054-1061页

作者： Wenjun Lv yu kang yunbo Zhao Department of Automation University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Fire Science Department of Automation and Institute of Advanced TechnologyUniversity of Science and Technology of ChinaHefei 230027China Key Laboratory of Technology in GeoSpatial Information Processing and Application System Chinese Academy of SciencesBeijing 100190China College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China

In this paper, optimal filtering problem for a class of linear Gaussian systems is studied. The system states are updated at a fast uniform sampling rate and the measurements are sampled at a slow uniform sampling rate. The updating rate of system states is several times the sampling rate of measurements and the multiple is constant. To solve the problem,we will propose a self-tuning asynchronous filter whose contributions are twofold. First, the optimal filter at the sampling times when the measurements are available is derived in the linear minimum variance sense. Furthermore, considering the variation of noise statistics, a regulator is introduced to adjust the filtering coefficients adaptively. The case studies of wheeled robot navigation system and air quality evaluation system will show the effectiveness and practicability in engineering.

关键词： Air quality evaluation system linear Gaussian system wheeled robot navigation system

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艺术院校舞蹈与非舞蹈学员髋关节运动伤比较

中国矫形外科杂志 2024年第12期32卷 1069-1074页

作者：李奕博李海鹏吴毅东于康康李中耀甘露王宇李春宝解放军总医院第四医学中心北京100010

[目的]调查比较某艺术院校舞蹈专业与非舞蹈专业髋关节运动伤的发生特点。[方法]问卷调查分析2023年9月—2023年12月某艺术院校580位学员的髋关节运动伤发生特点,其中舞蹈专业107例,非舞蹈专业473例,并进行两组间比较。调查髋关节运动... 详细信息

[目的]调查比较某艺术院校舞蹈专业与非舞蹈专业髋关节运动伤的发生特点。[方法]问卷调查分析2023年9月—2023年12月某艺术院校580位学员的髋关节运动伤发生特点,其中舞蹈专业107例,非舞蹈专业473例,并进行两组间比较。调查髋关节运动伤的影响因素。[结果]舞蹈专业学员的年龄[(23.1±3.0)岁vs(25.4±1.7)岁,P<0.001]、BMI[(20.6±2.6)kg/m^(2)vs(21.5±2.3)kg/m^(2),P=0.001]均显著小于非舞蹈学员。舞蹈专业出现髋关节疼痛比率显著高于非舞蹈专业[双髋(15.6%vs 11.2%,P<0.05),左髋(7.5%vs 5.7%,P<0.05),右髋(12.10%vs 4.7%,P<0.05)]。舞蹈专业学员在发生髋痛性质排在前3位分别为酸痛18例(16.8%)、刺痛15例(14.0%)、隐痛11例(10.3%)。从髋部症状来看,关节弹响是最主要的表现症状,行走、盘腿、下蹲等因素更容易加重舞蹈专业学员出现髋部弹响(P<0.05)。舞蹈专业学员通常会有不稳定的感觉(4.7%)、髋关节绞索及卡顿(6.5%)、小腿麻木无力等症状(4.7%),这会对学员在运动锻炼(28.0%)中造成影响(P<0.05)。训练因素(98.1%)、运动项目因素(39.9%)、个人因素(41.9%)是诱发舞蹈专业学员髋关节运动伤的主要因素。[结论]髋关节运动伤是舞蹈专业学员在校期间较为常见的伤病,右髋是主要疼痛部位。影响学员运动训练。运动前热身未到位、训练强度过大和自身动作失误是舞蹈专业学员主要受伤因素。

关键词：艺术院校舞蹈髋关节损伤

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废聚烯烃塑料裂解回收技术研究进展

石油化工 2024年第4期53卷 615-621页

作者：江珊刘红梅张蓝溪亢宇刘东兵中石化(北京)化工研究院有限公司北京100013

塑料产量过剩及遗弃造成了严重的环境污染问题,废聚烯烃塑料的化学回收和利用是解决这一问题的重要途径之一。综述了废聚烯烃塑料热裂解和催化裂解回收技术的研究进展,热裂解技术是化学回收的基础,废聚烯烃塑料催化裂解制高价值单体是... 详细信息

塑料产量过剩及遗弃造成了严重的环境污染问题,废聚烯烃塑料的化学回收和利用是解决这一问题的重要途径之一。综述了废聚烯烃塑料热裂解和催化裂解回收技术的研究进展,热裂解技术是化学回收的基础,废聚烯烃塑料催化裂解制高价值单体是新一代技术的发展趋势。未来应基于催化剂的设计和催化工程的优化,促进废聚烯烃塑料的循环利用,推动社会可持续发展。

关键词：废塑料热裂解催化裂解

Price-Based Residential Demand Response Management in Smart Grids:A Reinforcement Learning-Based Approach

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IEEE/CAA Journal of Automatica Sinica 2022年第1期9卷 123-134页

作者： Yanni Wan Jiahu Qin Xinghuo yu Tao Yang yu kang Department of Automation University of Science and Technology of ChinaHefei 230027China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China School of Engineering RMIT UniversityVIC 3000Australia State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China Department of Automation State Key Laboratory of Fire ScienceInstitute of Advanced TechnologyUniversity of Science and Technology of ChinaHefei 230027China Key Laboratory of Technology in Geo-Spatial Information Processing and Application Systems Chinese Academy of SciencesBeijing 100190China

This paper studies price-based residential demand response management(PB-RDRM)in smart grids,in which non-dispatchable and dispatchable loads(including general loads and plug-in electric vehicles(PEVs))are both *** PB-RDRM is composed of a bi-level optimization problem,in which the upper-level dynamic retail pricing problem aims to maximize the profit of a utility company(UC)by selecting optimal retail prices(RPs),while the lower-level demand response(DR)problem expects to minimize the comprehensive cost of loads by coordinating their energy consumption *** challenges here are mainly two-fold:1)the uncertainty of energy consumption and RPs;2)the flexible PEVs’temporally coupled constraints,which make it impossible to directly develop a model-based optimization algorithm to solve the *** address these challenges,we first model the dynamic retail pricing problem as a Markovian decision process(MDP),and then employ a model-free reinforcement learning(RL)algorithm to learn the optimal dynamic RPs of UC according to the loads’*** proposed RL-based DR algorithm is benchmarked against two model-based optimization approaches(i.e.,distributed dual decomposition-based(DDB)method and distributed primal-dual interior(PDI)-based method),which require exact load and electricity price *** comparison results show that,compared with the benchmark solutions,our proposed algorithm can not only adaptively decide the RPs through on-line learning processes,but also achieve larger social welfare within an unknown electricity market environment.

关键词： Demand response management(DRM) Markovian decision process(MDP) Monte Carlo simulation reinforcement learning(RL) smart grid

三维超声血管斑块定量分析在颈动脉斑块性质诊断与评估中的临床价值研究

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科技与健康 2024年第10期3卷 9-12页

作者：康佳沙晓溪康彧何兰芳成都中医药大学附属医院超声科四川成都610075

探讨三维超声血管斑块定量分析技术在颈动脉斑块性质诊断与评估中的临床价值。选取2022年1月—2023年1月于成都中医药大学附属医院就诊的85例颈动脉斑块患者作为研究对象。所有患者均接受三维超声血管斑块定量分析技术检查以及颈动脉CT... 详细信息

探讨三维超声血管斑块定量分析技术在颈动脉斑块性质诊断与评估中的临床价值。选取2022年1月—2023年1月于成都中医药大学附属医院就诊的85例颈动脉斑块患者作为研究对象。所有患者均接受三维超声血管斑块定量分析技术检查以及颈动脉CTA检查,以CTA检查结果作为金标准,明确颈动脉狭窄程度、声像图特征以及斑块性质情况。结果显示,不同狭窄程度患者NWI比较,差异有统计学意义(P0.05)。研究发现,三维超声血管斑块定量分析技术在评估颈动脉狭窄程度以及斑块性质方面具有较高的准确性,能够对相关指标进行量化分析,该检查方案无创、方便、快捷,具有临床应用及推广价值。

关键词：三维超声血管斑块定量分析技术颈动脉CTA 颈动脉斑块性质颈动脉狭窄程度

Sampled-data Observer Design for a Class of Stochastic Nonlinear Systems Based on the Approximate Discrete-time Models

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IEEE/CAA Journal of Automatica Sinica 2017年第3期4卷 507-511页

作者： Xinxin Fu yu kang Pengfei Li Department of Automation University of Science and Technology of China State Key Laboratory of Fire Science Department of AutomationInstitute of Advanced TechnologyUniversity of Science and Technology of China Key Laboratory of Technology in GeoSpatial Information Processing and Application System Chinese Academy of Sciences IEEE

In this paper,we studied the approximate sampleddata observer design for a class of stochastic nonlinear ***-Maruyama approximation was investigated in this paper because it is the basis of other higher precision numerical methods,and it preserves important structures of the nonlinear ***,the form of Euler-Maruyama model is simple and easy to be *** results provide a reference for sampled-data observer design method for such stochastic nonlinear systems,and may be useful to many practical control applications,such as tracking control in mechanical *** the effectiveness of the approach is demonstrated by a simulation example.

关键词： Approximation model exponentially bounded sampled-data observer stochastic nonlinear