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基于EDEM-ADAMS的甘薯水平移栽机构优化设计

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中国农机化学报 2024年第1期45卷 35-41,F0003页

作者：张云鹏谭芊许鹏陈栋泉杨然兵海南大学机电工程学院海口市570228 海南大学信息与通信工程学院海口市570228

针对现有甘薯水平栽插移栽机械较少、移栽位姿不符合农艺要求等问题,结合甘薯栽植农艺要求,设计一款能实现水平栽插的甘薯移栽机构。通过建立数学模型对移栽机构的整体结构和关键部件进行优化设计。以机构前进速度、机构安装高度为试验... 详细信息

针对现有甘薯水平栽插移栽机械较少、移栽位姿不符合农艺要求等问题,结合甘薯栽植农艺要求,设计一款能实现水平栽插的甘薯移栽机构。通过建立数学模型对移栽机构的整体结构和关键部件进行优化设计。以机构前进速度、机构安装高度为试验因素,通过EDEM-ADAMS耦合仿真对薯苗入土深度与土中直线长度进行仿真试验与参数优化,仿真试验的最优参数为:机构前进速度0.22 m/s、安装高度181 mm。田间试验结果表明,薯苗入土深度平均合格率与土中直线长度合格率分别为95.32%、93.12%,符合甘薯水平栽插农艺要求。

关键词：甘薯移栽机水平栽插耦合仿真

Novel sliding-mode disturbance observer-based tracking control with applications to robot manipulators

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Science China(Information Sciences) 2021年第7期64卷 80-91页

作者： Tairen SUN Long CHENG Zengguang HOU Min tan School of Electrical and Information Engineering Jiangsu University State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences School of Artificial Intelligence University of Chinese Academy of Sciences

This paper proposes a sliding-mode disturbance observer(SMDOB)-based tracking controller for a class of nonlinear systems with modeling uncertainties and external disturbances. The SMDOB is constructed using an extended state observer embedded by a filtered sliding mode term. The chattering caused by the sliding mode is compressed by the frequency bandwidths of both the extended state observer and the control system. The novelties of the proposed controller are as follows:(1) The semiglobal asymptotical stability of the combined controller-observer system is guaranteed without the boundedness assumption of the time derivatives of modeling uncertainties;(2) the SMDOB can be implemented with a low complexity because of only three parameters to be tuned. Applications to robot manipulators illustrate the effectiveness of the SMDOB-based tracking control strategy.

关键词： adaptive control robot manipulator disturbance observer sliding mode

Current situation and forecast of environmental risks of a typical lead-zinc sulfide tailings impoundment based on its geochemical characteristics

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Journal of Environmental Sciences 2020年第7期32卷 120-128页

作者： Tao Chen Zi-ang Yan Damao Xu Minghui Wang Jian Huang Bo Yan Xianming Xiao Xunan Ning SCNU Environmental Research Institute Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Environmental Theoretical ChemistrySouth China Normal UniversityGuangzhou 510006China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510640China State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China China University of Geosciences Beijing 100083China

The potential environmental implications of a Pb(Lead)-Zn(Zinc)sulfide tailing impoundment were found to be dependent on its geochemical *** typical lead-zinc sulfide tailing impoundment was *** boreholes were set with the grid method and 36 tailings were sampled and *** to the results of metal content analysis,the tailing samples contained considerably high contents of heavy metals,ranging from 6.99 to 89.0 mg/kg for Cd,75.3 to 602 mg/kg for Cu,0.53%to 2.63%for Pb and 0.30%to 2.54%for *** of the heavy metals in the sample matrix showed a uniform concentration distribution,except ***,Pb,Zn,and Mn were associated with each other,and were considered to be the dominant contributors based on hierarchical cluster ***,SEM and XPS were employed for evaluation of the tailing weathering characteristics,confirming that the tailings had undergone intensive *** maximum potential acidity of the tailings reached 244 kg H2SO4/ton;furthermore,the bioavailability of heavy metals like Pb,Cd,Cr,Cu,and Zn was 37.8%,12.9%,12.2%,5.95%,and 5.46%*** metals would be potentially released into drainage by the weathering *** of a gastrointestinal model showed that Pb,Cr,Ni and Cu contained in the tailings were high-risk ***,control of the heavy metals’migration and their environmental risks should be planned from the perspective of geochemistry.

关键词： Pb-Zn tailings impoundment Geochemical characteristics Distribution of the metals Weathering process Environmental risk assessment

DLC膜对金刚石纳米柱NV色心发光收集强度的影响

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量子电子学报 2024年第5期41卷 793-801页

作者：李文斌谭心潘超贺占清杨桥内蒙古科技大学机械工程学院内蒙古包头014010

金刚石氮空位(NV)色心发光收集强度的提高是实现单光子源技术的关键。本工作将锥状的类金刚石(DLC)梯度减反膜引入纳米柱色心单光子源中,旨在从色心的自发辐射速率与光子收集效率两方面提高NV色心的发光收集强度。采用时域有限差分(FDTD... 详细信息

金刚石氮空位(NV)色心发光收集强度的提高是实现单光子源技术的关键。本工作将锥状的类金刚石(DLC)梯度减反膜引入纳米柱色心单光子源中,旨在从色心的自发辐射速率与光子收集效率两方面提高NV色心的发光收集强度。采用时域有限差分(FDTD)法对带有DLC膜的金刚石纳米柱复合结构进行了光学仿真,探究了不同结构参数的DLC薄膜对金刚石纳米柱NV色心光子收集强度、出射效率及自发辐射速率的影响,并且通过优化得到了最大收集强度下的结构参数。仿真结果表明,引入DLC膜能够使金刚石纳米柱中NV色心获得更高的光子出射效率(≥1%),并且能够改变纳米柱内部电场分布,使色心自发辐射速率增加16.8%,最终使光子的总收集强度增加15.5%。

关键词：量子光学收集强度时域有限差分金刚石纳米柱NV色心类金刚石梯度减反膜自发辐射速率

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In-situ experiment tests and particulate simulations on powder paving process of additive manufacturing

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Particuology 2023年第3期74卷 164-172页

作者： tan Cheng Hui Chen Qing Teng Qingsong Wei State Key Lab of Materials Forming and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China Department of Mechanical Engineering National University of SingaporeSingapore117575Singapore

In this work,in-situ experimental tests are first performed to investigate the powder spreading process of additive manufacturing,where different kinds of scrapers and spreading speeds are *** kinetic behaviours of individual powder particles are discussed by discrete element method *** is found that the decrease of inclination angle of the scraper improves the powder pressure and compaction in the spreading process,leading to a denser powder flow and thus a denser powder *** increase of spreading speed also improves the powder pressure and compaction in the spreading ***,the powder flow becomes looser due to the volume dilation,and thus the quality of the paved powder bed *** industrial applications,if the higher powder spreading speed is employed to improve the processing efficiency,the scraper with a smaller inclination angle can be used to ensure the powder bed quality.

关键词： Additive manufacturing Powder paving Packing quality Powder bed Inclination angle In-situ measurement

Bright yellow-emitting long persistent luminescence from Mn^(2+)-activated strontium aluminate phosphor

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Journal of Rare Earths 2022年第7期40卷 1029-1036页

作者： Wenzhi Sun Tao tan Jize Cai Hongwu Zhang School of Chemistry and Materials Science Ludong UniversityYantai 264025China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

We developed bright yellow-emitting long persistent luminescence(LPL)materials Sr_(4)Al_(14)O_(25):Mn^(2+)and Sr_(4)Al_(14)O_(25):Mn^(2+),N(N=Zr^(4+),Ho^(3+),Er^(3+))by high temperature solid-state *** addition of Zr^(4+),Ho^(3+)and Er^(3+)can regulate trap distributions and improve energy storage ability of the *** LPL perfo rmance of SAO:Mn^(2+),Ho^(3+)is optimal,considering LPL intensity and duration *** LPL of SAO:Mn^(2+),Ho^(3+)can be observed for 3 h by naked eyes in dark after removing the excitation *** of LPL spectra are different from those of PL,because the two types of Mn^(2+)centers do not play equal parts in LPL and photoluminescence(PL).Trap depths of TL peaks centered at 354 K(peak 1)and 455 K(peak 2)are 0.60 and 0.72 eV,*** peak 1 at 354 K is the effective TL peak responsible for *** SAO:Mn^(2+),Ho^(3+),Mn^(2+)ions doped in Al^(3+)sites serve as emitting centers,and positively charged HoSr defects are the main effective trap ***,a feasible LPL mechanism of SAO:Mn^(2+),Ho^(3+)was proposed to clarify the generation process of LPL.

关键词： Long persistent phosphors Sr_(4)Al_(14)O_(25):Mn^(2+) Trap distributions Afterglow mechanism Rare earths

神经外科Ⅰ类切口围手术期抗菌药物预防使用药学路径的回顾性评价

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中国药房 2024年第17期35卷 2147-2151页

作者：王金平赵婕杨春燕赖晓敏朱云腾武志昂沈阳药科大学工商管理学院沈阳110016 深圳市第二人民医院药学部广东深圳518035 广西中医药大学研究生院南宁530000

目的探讨神经外科Ⅰ类切口手术患者围手术期预防使用抗菌药物药学路径的可行性。方法运用前期建立的神经外科Ⅰ类切口手术患者围手术期预防使用抗菌药物药学路径,回顾性评估127例神经外科Ⅰ类切口手术患者围手术期预防使用抗菌药物的情... 详细信息

目的探讨神经外科Ⅰ类切口手术患者围手术期预防使用抗菌药物药学路径的可行性。方法运用前期建立的神经外科Ⅰ类切口手术患者围手术期预防使用抗菌药物药学路径,回顾性评估127例神经外科Ⅰ类切口手术患者围手术期预防使用抗菌药物的情况,运用药学路径中“抗菌药物预防使用评分体系”进行术前评分,并与患者实际用药情况比较,结合现有《抗菌药物临床应用指导原则(2015版)》(以下简称为《指导原则》)进行分析。对于术中抗菌药物追加次数及术后抗菌药物预防使用时间,药学路径也创新性提出可改进的关键点,通过与患者实际的用药情况进行了对比,探讨《指导原则》可尝试更新的方向。结果依据回顾性分析结果,神经外科Ⅰ类切口手术中除了《指导原则》已建议的不推荐颅骨肿物切除术和颈动脉内膜切除术患者术前预防使用抗菌药物外,内镜下三叉神经微血管减压术、关节镜其他特指关节检查、脊神经根减压术、内镜下腰椎髓核切除术、硬脊膜修补术、椎管减压术手术也可进一步探索术前不预防性使用抗菌药物;同时,对于神经外科Ⅰ类切口手术患者术中、术后抗菌药物的使用,结合手术时间术中可考虑进行第2次追加抗菌药物,手术患者如出现脑脊液漏,建议可适当延长抗菌药物预防使用时间。结论药学路径的应用可更有针对性地分析抗菌药物预防使用的关键点,推动了Ⅰ类切口围手术期抗菌药物管理方式从“定性、经验”的管理向“定量、科学”的管理转型。

关键词：药学路径神经外科 Ⅰ类切口抗菌药物预防用药

Utility Aware Offloading for Mobile-Edge Computing

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Tsinghua Science and Technology 2021年第2期26卷 239-250页

作者： Ran Bi Qian Liu Jiankang Ren Guozhen tan School of Computer Science and Technology Dalian University of TechnologyDalian 116024China

Mobile-edge computing casts the computation-intensive and delay-sensitive applications of mobile devices onto network *** offloading incurs extra communication latency and energy cost,and extensive efforts have focused on offloading *** metrics of the system utility are defined to achieve satisfactory quality of ***,most existing works overlook the balance between throughput and *** study investigates the problem of finding an optimal offloading scheme in which the objective of optimization aims to maximize the system utility for leveraging between throughput and *** on Karush-Kuhn-Tucker condition,the expectation of time complexity is analyzed to derive the optimal scheme.A gradient-based approach for utility-aware task offloading is ***,we provide an increment-based greedy approximation algorithm with 1+1/(e-1)*** results show that the proposed algorithms can achieve effective performance in utility and accuracy.

关键词： utility approximation algorithm quality of experience mobile edge computing

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钒酸铋基异质结光催化剂研究进展

应用化工 2024年第2期53卷 408-413页

作者：肖力光王一鸣雷潭吉林建筑大学材料科学与工程学院吉林长春130118

综述了钒酸铋(BiVO_(4))基异质结光催化材料的研究进展,针对BiVO_(4)基异质结光催化材料带隙较窄、光生载流子复合率较高等缺点,阐述了BiVO_(4)基异质结光催化材料的异质结类型,详细介绍了BiVO_(4)基异质结光催化材料在水分解领域、降... 详细信息

综述了钒酸铋(BiVO_(4))基异质结光催化材料的研究进展,针对BiVO_(4)基异质结光催化材料带隙较窄、光生载流子复合率较高等缺点,阐述了BiVO_(4)基异质结光催化材料的异质结类型,详细介绍了BiVO_(4)基异质结光催化材料在水分解领域、降解有机污染物、还原CO_(2)和重金属离子领域的研究进展,分析了BiVO_(4)基异质结光催化材料目前存在的问题,对今后的研究重点和方向做出了展望。

关键词：光催化钒酸铋异质结研究进展