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Data-Driven Active Disturbance Rejection Control of Plant-Protection Unmanned Ground Vehicle Prototype: A Fuzzy Indirect Iterative Learning Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1892-1894页

作者： Tao Chen Ruiyuan Zhao jian Chen Zichao zhang College of Engineering China Agricultural UniversityBeijing 100083China Key Laboratory of Smart Agricultural Technology in Tropical South China Ministry of Agriculture and Rural AffairsGuangzhou 510642China

Dear Editor,This letter proposes a fuzzy indirect iterative learning(FIIL)active disturbance rejection control(ADRC)scheme to address the impact of uncertain factors of plant-protection unmanned ground vehicle(UGV),in which ADRC is a data-driven model-free control algorithm that only relies on the input and output data of the *** on the established nonlinear time-varying dynamic model including dynamic load(medicine box),the FIIL technology is adopted to turn the bandwidth and control channel gain online,in which the fuzzy logic system is used to update the gain parameters of iterative learning in real *** and experiment show the FIIL-ADRC scheme has better control performance.

关键词： Active scheme iterative

Accurate simulations of pure-viscoacoustic wave propagation in tilted transversely isotropic media

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Petroleum Science 2024年第2期21卷 866-884页

作者： Qiang Mao jian-Ping Huang Xin-Ru Mu Ji-Dong Yang Yu-jian zhang Geosciences Department China University of Petroleum(East China)Qingdao266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266207ShandongChina

Forward modeling of seismic wave propagation is crucial for the realization of reverse time migration(RTM) and full waveform inversion(FWI) in attenuating transversely isotropic media. To describe the attenuation and anisotropy properties of subsurface media, the pure-viscoacoustic anisotropic wave equations are established for wavefield simulations, because they can provide clear and stable wavefields. However, due to the use of several approximations in deriving the wave equation and the introduction of a fractional Laplacian approximation in solving the derived equation, the wavefields simulated by the previous pure-viscoacoustic tilted transversely isotropic(TTI) wave equations has low accuracy. To accurately simulate wavefields in media with velocity anisotropy and attenuation anisotropy, we first derive a new pure-viscoacoustic TTI wave equation from the exact complex-valued dispersion formula in viscoelastic vertical transversely isotropic(VTI) media. Then, we present the hybrid finite-difference and low-rank decomposition(HFDLRD) method to accurately solve our proposed pure-viscoacoustic TTI wave equation. Theoretical analysis and numerical examples suggest that our pure-viscoacoustic TTI wave equation has higher accuracy than previous pure-viscoacoustic TTI wave equations in describing q P-wave kinematic and attenuation characteristics. Additionally, the numerical experiment in a simple two-layer model shows that the HFDLRD technique outperforms the hybrid finite-difference and pseudo-spectral(HFDPS) method in terms of accuracy of wavefield modeling.

关键词： Pure-viscoacoustic TTI wave equation Attenuation anisotropy Seismic modeling Low-rank decomposition method

应用于直线电机的平滑切换模糊PID控制方法

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中国电机工程学报 2006年第8期26卷 132-136页

作者：牛志刚张建民太原理工大学机械工程学院山西省太原市030024 北京理工大学机械与车辆工程学院北京市海淀区100081

为了适应直线电机的快速动态特性,抑制由于直接驱动使参数摄动和负载扰动等不确定因素对伺服特性的影响,提出了一种新的平滑函数模型,设计了平滑切换式模糊PID复合控制器,并应用于直线电机位置伺服控制。通过模糊控制提高伺服系统的动... 详细信息

为了适应直线电机的快速动态特性,抑制由于直接驱动使参数摄动和负载扰动等不确定因素对伺服特性的影响,提出了一种新的平滑函数模型,设计了平滑切换式模糊PID复合控制器,并应用于直线电机位置伺服控制。通过模糊控制提高伺服系统的动态性能,用PID控制保证系统的稳态性能,利用平滑函数改善控制切换过程。在PRS-XY型混联机床上的应用表明,该控制算法明显提高了伺服系统的动态性能,减小了位置跟随误差,对非线性扰动因素具有良好的适应性。

关键词：直线电机位置伺服控制平滑函数平滑切换模糊比例积分微分复合控制器

Allelopathic potentials of surrounding vegetation on seedling establishment of alpine cushion Arenaria polytrichoides

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Journal of Plant Ecology 2024年第2期17卷 146-160页

作者： Xu-Fang Chen Li-Shen Qian Hong-Hua Shi Ya-Zhou zhang min-Shu Song Hang Sun jian-Guo Chen Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina University of Chinese Academy of Sciences Beijing 101408China

When facilitating other species and sustaining plant community structures and biodiversity,alpine cushion plants simultaneously experience negative feedback effects from surrounding ***,the impact of surrounding vegetation on cushion dynamics remains poorly understood,particularly in terms of allelopathic *** investigate the allelopathic potentials of surrounding vegetation on seedling establishment of the typical cushion plant Arenaria polytrichoides *** an elevational gradient,we extracted potential allelopathic compounds and tested their impacts on seed germination and seedling growth of *** addition,exclusion experiments using activated carbon were conducted to further elucidate these *** results demonstrate that surrounding vegetation exhibits certain allelopathic potentials on *** seedling establishment,with variations observed based on elevation,source and concentration of allelopathy compounds,as well as growing ***,low-elevation vegetation exerts pronounced suppression on seedling ***,higher-elevation vegetation generally shows no effect on seed germination but stimulates seedling growth through allelopathy ***,aboveground vegetation predominantly inhibits both seed germination and seedling growth in low-elevation communities;however,the effects of belowground vegetation depend on elevation and extract concentration *** identifed allelopathic potentials of surrounding vegetation signifcantly infuence the population dynamics of cushion *** by potentially accelerating population degeneration in lower-elevation communities while ensuring consistent population recruitment and expansion in higher-elevation communities.

关键词： allelopathic potential community dynamic cushion plant seed germination seedling growth

秦山第二核电厂蒸汽发生器液位控制系统PID参数整定

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核动力工程 2005年第3期26卷 272-276页

作者：董化平张建民西安交通大学 710049

基于核电厂SimPort仿真平台构建了秦山第二核电厂1号机组蒸汽发生器液位控制系统仿真模型,在该仿真模型上进行了各种工况下的瞬态仿真实验和研究,获得了液位控制系统PID参数的整定值,其中液位控制器的KP=4.25,TI=425s,TD=10s;流量控制器... 详细信息

基于核电厂SimPort仿真平台构建了秦山第二核电厂1号机组蒸汽发生器液位控制系统仿真模型,在该仿真模型上进行了各种工况下的瞬态仿真实验和研究,获得了液位控制系统PID参数的整定值,其中液位控制器的KP=4.25,TI=425s,TD=10s;流量控制器的KP=1.0,TI=13s。这些参数整定值与实际值基本一致,可供工程技术人员参考。

关键词：核电厂蒸汽发生器液位控制系统瞬态仿真整定值

Hemorrhagic cystitis in gastric cancer after nanoparticle albuminbound paclitaxel:A case report

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 1084-1090页

作者： Xin-Jie zhang jian Lou Department of Cancer Center The Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina

BACKGROUND The advanced first-line regimen for advanced gastric cancer is based on a combination of fluoropyrimidine and platinum and/or paclitaxel(PTX),forming a two-or three-drug *** to conventional PTX,nanoparticle albumin-bound PTX(Nab-PTX)has better therapeutic effects and fewer adverse effects reported in ***-PTX is a great option for patients presenting with advanced gastric ***,we highlight an adverse event(hemorrhagic cystitis)of Nab-PTX in advanced gastric *** SUMMARY A 55-year-old male was diagnosed with lymph node metastasis after a laparo-scopic-assisted radical gastrectomy for gastric cancer that was treated by Nab-PTX and S-1(AS).On the 15th day after treatment with AS,he was diagnosed with hemorrhagic *** Physicians should be aware that hemorrhagic cystitis is a potential adverse event associated with Nab-PTX treatment.

关键词： Nanoparticle albumin-bound paclitaxel Hemorrhagic cystitis Gastric cancer Adverse event Case report

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边坡稳定分析中组合滑面的构造模型

岩土工程学报 2005年第8期27卷 855-859页

作者：张鲁渝张建民清华大学岩土工程研究所北京100084

坡体的地质构造对滑面几何形状具有决定性的影响,而现有稳定分析理论不能很好地考虑这种影响。本文提出了一个组合滑面的构造模型,它分为两部分:一部分模拟不受地质影响的滑面,另一部分则模拟受软弱结构面控制的滑面。该模型不仅可以考... 详细信息

坡体的地质构造对滑面几何形状具有决定性的影响,而现有稳定分析理论不能很好地考虑这种影响。本文提出了一个组合滑面的构造模型,它分为两部分:一部分模拟不受地质影响的滑面,另一部分则模拟受软弱结构面控制的滑面。该模型不仅可以考虑单条或多条软弱结构面并存的情况,而且可以模拟各种复杂组合滑面,如圆弧、样条曲线以及折线组合滑面等,这些成果为研究复杂临界组合滑面的搜索算法奠定了基础。算例分析表明,提出的模型不仅可行而且具有广阔的应用前景。

关键词：组合滑面软弱结构面边坡稳定分析

Effect of temperature and time on the precipitation ofκ-carbides in Fe-28Mn-10Al-0.8C low-density steels:Aging mechanism and its impact on material properties

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International Journal of minerals,Metallurgy and Materials 2024年第10期31卷 2189-2198页

作者： Yulin Gao min zhang Rui Wang Xinxin zhang Zhunli Tan Xiaoyu Chong School of Mechanical Electronic and Control EngineeringMaterials Science and Engineering Research CenterBeijing Jiaotong UniversityBeijing 100044China Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

In low-density steel,κ-carbides primarily precipitate in the form of nanoscale particles within austenite ***,their precipitation within ferrite matrix grains has not been comprehensively explored,and the second-phase evolution mechanism during aging remains *** this study,the crystallographic characteristics and morphological evolution ofκ-carbides in Fe-28Mn-10Al-0.8C(wt%)low-density steel at different aging temperatures and times and the impacts of these changes on the steels’microhardness and properties were comprehensively *** different heat treatment conditions,intragranularκ-carbides exhibited various morpho-logical and crystallographic characteristics,such as acicular,spherical,and short rod-like *** the initial stage of aging,acicularκ-carbides primarily precipitated,accompanied by a few spherical carbides.κ-Carbides grew and coarsened with aging time,the spherical carbides were considerably reduced,and rod-like carbides *** hardness testing demonstrated that the material’s hardness was affected by the volume fraction,morphology,and size ofκ-*** aging at higher temperatures led to an increase in carbide size and volume fraction,resulting in a gradual rise in *** deformation,the primary mechanisms for strengthening were dislocation strengthening and second-phase *** on these findings,potential strategies for improving material strength are proposed.

关键词： low-density steel κ-carbide solution-aging treatment hardness

Structure of the mantle transition zone in the central and western parts of the North China Craton using the receiver function 3D Kirchhoff migration method

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Science China Earth Sciences 2024年第9期67卷 2783-2795页

作者： min ZHU Qingju WU Jieyuan NING Ruiqing zhang Institute of Geophysics China Earthquake AdministrationBeijing 100081China Institute of Theoretical and Applied Geophysics Peking UniversityBeijing 100871China

Using data from the regional broadband dense temporary array deployed by the ChinArray project,we applied the three-dimensional(3D)Kirchhoff migration method of the teleseismic P-wave receiver function to investigate discontinuity structures of the mantle transition zone(MTZ)in the central and western parts of the North China Craton(NCC)using a highresolution 3D velocity model of the East Asian *** results show that the 410-km discontinuity beneath the Datong Volcano is depressed by~10 km,indicating the presence of a high-temperature anomaly near the depth of 410 km,which is likely related to small-scale mantle upwelling caused by the dehydration of the stagnant Pacific Plate in the *** upwelling of hot material provides a heat source for surface magmatic *** the Bohai Bay Basin,significant subsidence of the 660-km discontinuity is observed,and the transition zone here is extensively ***’s suggested that the anomalies in this region are related to the stagnation of the Pacific slab in the *** the thickness of the transition zone west of the North-South Gravity Lineament appears normal,we propose that the subducting front of the Pacific slab did not cross the gravity lineament in the *** comparison,the small-scale subsidence of the 660-km discontinuity and the thickening of the MTZ observed north of the Hannuoba Volcano likely indicate that the slab crossed the gravity lineament at its turning point and remained in the ***,a local thickening of the MTZ is observed in the Dabie orogenic belt of the Qinling *** is believed to be a combined effect of lithospheric delamination into the transition zone in the lower Yangtze region and the stagnation of the Pacific Plate.

关键词： North China Craton Mantle transition zone Receiver function migration Datong Volcano