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Global practical stabilization of the double integrator system with an imperfect sensor and subject to a bounded disturbance

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Control Theory and Technology 2024年第3期22卷 468-478页

作者： Zhiyuan Zhu yuanlong li Zongli lin Department of Automation Shanghai Jiao Tong Universityand Key Laboratory of System Control and Information Processing of Ministry of EducationShanghai 200240China Charles L.Brown Department of Electrical and Computer Engineering University of VirginiaP.0.Box 400743CharlottesvilleVA 22904-4743USA

This paper is concerned with global practical stabilization of the double integrator system with an imperfect sensor and subject to an additive bounded output *** imperfect sensor nonlinearity possesses the nonlinear characteristics of saturation and dead *** of the presence of output dead zone and the additive disturbance,the states cannot be expected to driven into an arbitrarily small neighborhood of the *** solve the global practical stabilization problem,we proposes a low gain-based linear dynamic output feedback law,under which the first state enters and remains in a bounded set whose size is depended on the bound of disturbance and the range of dead zone and the second state enters and remains in a pre-specified arbitrarily small set,both in finite *** results illustrate the effectiveness of our proposed control method.

关键词： Output saturation Disturbance rejection Output dead zone Low gain feedback-linear output feedback Practical stabilization

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国内外高水平马拉松比赛表现节奏特征分析

运动精品 2024年第7期43卷 94-98页

作者：李沅隆福建师范大学体育科学学院福建福州350100

基于2019-2023年国内外年度马拉松最好成绩,采用文献资料、数理统计和录像观察等方法,文章对运动员的分段成绩、节奏策略和速度变异等进行了研究,发现:我国运动员比赛中的速度慢,配速差异呈负值,绝对值大;我国运动员均采用了积极型策略... 详细信息

基于2019-2023年国内外年度马拉松最好成绩,采用文献资料、数理统计和录像观察等方法,文章对运动员的分段成绩、节奏策略和速度变异等进行了研究,发现:我国运动员比赛中的速度慢,配速差异呈负值,绝对值大;我国运动员均采用了积极型策略,国外运动员主要采用均匀+消极型的策略;国外运动员分段成绩更快,段落速度变化率更小,运动员的节奏策略与分段与首分段速度百分比、分段速度变化一致;国外运动员耐力系数更高。建议:首先,运动员要选择合理的节奏策略与速度分配方案,加强高速保持能力;其次,注重心理素质、自我调整等能力的训练;运动员进入平台阶段时,可通过提高的耐力系数实现新的突破。

关键词：节奏策略马拉松速度分配运动员

New Record Ocean Temperatures and Related Climate Indicators in 2023

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Advances in Atmospheric Sciences 2024年第6期41卷 1068-1082页

作者： lijing CHENG John ABRAHAM Kevin E.TRENBERTH Tim BOYER Michael EMANN Jiang ZHU Fan WANG Fujiang YU Ricardo LOCARNINI John FASULLO Fei ZHENG yuanlong li Bin ZHANG liying WAN Xingrong CHEN Dakui WANG licheng FENG Xiangzhou SONG Yulong liU Franco RESEGHETTI Simona SIMONCELli Viktor GOURETSKI Gengxin CHEN Alexey MISHONOV Jim REAGAN Karina VON SCHUCKMANN Yuying PAN Zhetao TAN Yujing ZHU Wangxu WEI Guancheng li Qiuping REN lijuan CAO Yayang LU International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of St.Thomas School of EngineeringMinnesota 55105USA NSF National Center for Atmospheric Research BoulderColorado 80307USA University of Auckland Auckland 1010New Zealand National Oceanic and Atmospheric Administration National Centers for Environmental InformationSilver SpringMaryland 20910USA Department of Earth and Environmental Science University of PennsylvaniaPhiladelphiaPennsylvania 19104USA Institute of Oceanology Chinese Academy of SciencesQingdao 266071China National Marine Environmental Forecasting Center Ministry of Natural Resources of ChinaBeijing 100081China Oceanographic Data Center Chinese Academy of SciencesQingdao 266071China College of Oceanography Hohai UniversityNanjing 210098China National Marine Data and Information Service Tianjin 300171China Italian National Agency for New Technologies Energy and Sustainable Economic DevelopmentS.Teresa Research CenterLerici 19032Italy Istituto Nazionale di Geofisica e Vulcanologia Sede di BolognaBologna 40128Italy South China Sea Institute of Oceanology Chinese Academy of SciencesGuangzhou 510301China ESSIC/CISESS-MD University of MarylandCollege ParkMD20740USA Mercator Ocean International Toulouse 31400France Eco-Environmental Monitoring and Research Center Pearl River Valley and South China Sea Ecology and Environment AdministrationMinistry of Ecology and EnvironmentPRCGuangzhou 510611China National Meteorological Information Center China Meteorological AdministrationBeijing 100081China International Research Center of Big Data for Sustainable Development Goals Beijing 100094China

The global physical and biogeochemical environment has been substantially altered in response to increased atmospheric greenhouse gases from human *** 2023,the sea surface temperature(SST)and upper 2000 m ocean heat content(OHC)reached record *** 0–2000 m OHC in 2023 exceeded that of 2022 by 15±10 ZJ(1 Zetta Joules=1021 Joules)(updated IAP/CAS data);9±5 ZJ(NCEI/NOAA data).The Tropical Atlantic Ocean,the Mediterranean Sea,and southern oceans recorded their highest OHC observed since the *** with the onset of a strong El Niño,the global SST reached its record high in 2023 with an annual mean of~0.23℃ higher than 2022 and an astounding>0.3℃ above 2022 values for the second half of *** density stratification and spatial temperature inhomogeneity indexes reached their highest values in 2023.

关键词： ocean heat content salinity stratification global warming climate

基于传感器通信网络的变电一次设备温度过热远程监测方法

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通信电源技术 2024年第18期41卷 25-27页

作者：李原龙国网四川省电力公司眉山供电公司四川眉山620010

文章针对变电一次设备温度过热和监测响应慢的问题,提出一种基于DS18B20传感器和ZigBee无线通信网络的远程监测方法。该方法通过传感器节点实时采集温度数据,并传输至远程监控中心,利用分布式存储和动态阈值调整机制实现过热预警。实验... 详细信息

文章针对变电一次设备温度过热和监测响应慢的问题,提出一种基于DS18B20传感器和ZigBee无线通信网络的远程监测方法。该方法通过传感器节点实时采集温度数据,并传输至远程监控中心,利用分布式存储和动态阈值调整机制实现过热预警。实验证明,该方法能够有效提升监测响应速度,确保设备温度的实时准确监测,增强电力系统的安全性和稳定性。

关键词：传感器通信网络变电一次设备设备温度过热远程监测

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一种堆场使用效率计算方法

港口装卸 2024年第4期 53-54,57页

作者：李渊龙蒋强沧州黄骅港矿石港务有限公司

在港口生产作业环节,堆场智能高效地为货物缓冲储存、保管及交接提供支撑,是港口生产能力的重要保障。分析港口生产作业中堆场所面临的的问题,设计智能决策管理系统,以提高堆场的周转率及人机智能调配,助力智慧港口建设。

关键词：堆场效率计算智慧港口

结泥条件下TBM滚刀破岩能量演化机制及掘进参数优化研究

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矿业研究与开发 2024年第5期44卷 201-210页

作者：张鹏赵腾跃李元龙刘勃龙北京市政路桥股份有限公司北京100045 绍兴文理学院土木工程学院浙江绍兴市312000

岩石隧道掘进机(Tunnel Boring Machine,TBM)在泥岩地层掘进过程中,渣土易形成泥浆黏附在滚刀和刀盘表面,出现刀盘结“泥饼”现象,严重降低掘进效率。为了揭示结泥对TBM滚刀破岩效率的影响,防止滚刀结泥,使用离散元程序PFC3D模拟TBM滚... 详细信息

岩石隧道掘进机(Tunnel Boring Machine,TBM)在泥岩地层掘进过程中,渣土易形成泥浆黏附在滚刀和刀盘表面,出现刀盘结“泥饼”现象,严重降低掘进效率。为了揭示结泥对TBM滚刀破岩效率的影响,防止滚刀结泥,使用离散元程序PFC3D模拟TBM滚刀回转切割泥岩过程,计算了系统总能量E、弹性应变能Ee、摩擦能E_μ、阻尼能E_β、动能Ek和黏结能Ea,从能量演化角度研究结泥条件下TBM滚刀破岩机制。随后分析了不同刀盘推力、滚刀刀刃角和刀刃宽度下的TBM滚刀破岩过程中的能量特征,根据“累积热量和累积黏结能最低,且滚刀表面黏附的泥化物质量最小”的原则,对上述掘进参数进行优化。研究结果表明,PFC3D中的黏聚滚动阻力线性模型可实现滚刀结泥过程;在结泥情况下,泥化物的形成将显著提高机械做功,消耗大量能量,降低滚刀破岩效率;提高刀盘推力可以促进泥化物的形成,导致刀盘升温,诱发泥化物黏附在滚刀表面。选用刀刃角为40°的V形滚刀,设最优刀刃宽度为13 mm,可减小滚刀结泥情况。研究结果可为相关工程中预防刀盘结“泥饼”提供理论参考。

关键词：岩石隧道掘进机结泥能量破岩机制掘进参数

Thermohaline intrusions in the thermocline of the western tropical Pacific Ocean

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Acta Oceanologica Sinica 2013年第7期32卷 47-56页

作者： li yuanlong WANG Fan Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences Graduate University of Chinese Academy of Science

The existing high-resolution hydrographic data in the western tropical Pacilit; Ocean are used to explore the spatial distribution and primary characteristics of thermohaline intrusions in the thermocline. Statistics show that the vertical scales of intrusions are 20-40 m in the upper thermocline （22.0-26.0δ0） and 40-80 m in the lower thermocline （26.0-27.2δ0）. In the upper thermocline, the most intensive intrusions exist at the equatorial front （EF） where north/sonth Pacilic water masses converge, anti Ihe westward spreading of the north Pacilic tropical waler （NPTW） in the Philippines Sea also produces patches of intrusions surrounding its high-salinity tongue. In the lower thermocline, intrusions are also strong at the tropical front （TF） which is the boundary between the north Pacilic subtropical/tropical waters. At the bottom of the thermocline （at about 27.0δ0）, intrusions mainly exist near the western boundary, which are produced by intermediate water convergence through the advection of subthermocline western boundary Ilows. Most strikingly a ＂C＂-shape distribution of intrusions at around 26.4δ0 is revealed, covering the vicinity of the EF the TE and the Mindanao Current （MC）, i.e., tile western boundary pathway ol the norlh Pacilic subtrnpical cell （STC）. Synoptic section analysis reveals that intrusions are more prominent on the warm/sally flank ot the fronts, implying more cross-front tongues of cold/fresh water. Among the intrusions, those at the EF are of best lateral coherence which implies a unique driving mechanism involving near-inertial velocity perturbations near the equator.

关键词： thermohaline intrusions thermocline water mass western tropical Pacilic

Subtropical sea surface salinity maxima in the South Indian Ocean

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Journal of Oceanology and limnology 2020年第1期38卷 16-29页

作者： WANG Yu li yuanlong WEI Chuanjie North China Sea Off shore Engineering Survey Institute North China Sea Branch of Ministry of Natural ResourcesQingdao 266061China Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Engineering and Technology Department Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Subtropical sea surface salinity(SSS)maximum is formed in the subtropical South Indian Ocean(SIO)by excessive evaporation over precipitation and serves as the primary salt source of the *** SSS measurements by Aquarius satellite during September 2011-May 2015 detect three disconnected SSS maximum regions(>35.6)in the eastern(105°E-115°E,38°S-28°S),central(60°E-100°E,35°S-25°S),and western(25°E-40°E,38°S-20°S)parts of the subtropical SIO,*** structure is however not seen in gridded Argo *** of Argo profile data confirms the existence of the eastern maximum patch and also reveals SSS overestimations of Aquarius near the western and eastern *** subjected to large uncertainties,a mixed-layer budget analysis is employed to explain the seasonal cycle of *** eastern and central regions reach the highest salinity in February-March and lowest salinity in August-September,which can be well explained by surface freshwater forcing(SFF)*** is however not controlled by evaporation(E)or precipitation(P).Instead,the large seasonal undulations of mixed layer depth(MLD)is the key *** shallow(deep)MLD in austral summer(winter)amplifies(attenuates)the forcing effect of local positive E-P and causes SSS rising(decreasing).Ocean dynamics also play a ***,activity of mesoscale eddies is a critical factor regulating SSS variability in the eastern and western regions.

关键词： sea surface salinity(SSS) subtropical salinity maximum Aquarius Argo float freshwater flux

Semi-global weighted output average tracking of discrete-time heterogeneous multi-agent systems subject to input saturation and external disturbances

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Control Theory and Technology 2023年第3期21卷 315-333页

作者： Qilin Song yuanlong li Yijing Xie Zongli lin Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Department of Electrical Engineering University of Texas at ArlingtonArlington 76019TXUSA Charles L.Brown Department of Electrical and Computer Engineering University of VirginiaCharlottesville 22904-4743VAUSA

In this paper,we revisit the semi-global weighted output average tracking problem for a discrete-time multi-agent system subject to input saturation and external *** multi-agent system consists of multiple heterogeneous linear systems as leader agents and multiple heterogeneous linear systems as follower *** design both the state feedback and output feedback control protocols for each follower *** particular,a distributed state observer is designed for each follower agent that estimates the state of each leader *** the output feedback case,state observer is also designed for each follower agent to estimate its own *** these estimates,we design low gain-based distributed control protocols,parameterized in a scalar low gain *** is shown that,for any bounded set of the initial conditions,these control protocols cause the follower agents to track the weighted average of the outputs of the leader agents as long as the value of the low gain parameter is tuned sufficiently *** results illustrate the validity of the theoretical results.

关键词： Distributed average tracking Input saturation Low gain feedback Heterogeneous multi-agent systems Output regulation