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维普期刊数据库博看期刊

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驱控一体的旋拧式果实采摘执行器设计与试验

农机化研究 2025年第3期47卷 48-55页

作者：严童杰冯青春郭鑫杨宁江苏大学电气信息工程学院江苏镇江212000 北京市农林科学院智能装备技术研究中心北京100097 国家农业智能装备工程技术研究中心北京100097 农业智能装备技术北京市重点实验室北京100097

针对果园智能化采收作业需要,设计了支持总线扩展的驱控一体旋拧采摘末端执行器,旨在为多臂并行采摘机器人研发提供支撑。在对标准苹果树果实物理形态统计分析基础上,结合人工采摘方法,提出了“吸附-夹持-旋拧”的采摘机械操作方法,并... 详细信息

针对果园智能化采收作业需要,设计了支持总线扩展的驱控一体旋拧采摘末端执行器,旨在为多臂并行采摘机器人研发提供支撑。在对标准苹果树果实物理形态统计分析基础上,结合人工采摘方法,提出了“吸附-夹持-旋拧”的采摘机械操作方法,并设计了基于双舵机驱动的紧凑型采摘执行机构,对其吸盘、夹持和旋拧电机的关键参数进行了优化设计。面向多执行并行采摘需要,设计了基于CANopen通讯的采摘操作驱动器,实现了多执行器的总线扩展。通过现场试验对执行器作业性能进行了测试,结果表明:果实大小在60~100 mm之间,采摘成功率可达到90%,吸盘最优停留时间为1.00 s,吸盘最优接近距离为1.0 mm,最优旋拧角度为360°。

关键词：采摘机器人驱控一体旋拧采摘 CANopen

维普期刊数据库博看期刊

Synchronization of noise-perturbed optical systems with multiple time delays

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Chinese Physics B 2012年第2期21卷 187-192页

作者： Tang Mao-ning School of Science Huzhou UniversityHuzhou 313000China

In this paper, complete synchronization and generalized synchronization between two unidirectionally coupled optical systems with multiple time delays and noise perturbation are investigated. Sufficient conditions for both complete synchronization and generalized synchronization are rigorously established. Numerical simulations fully support the theoretical results. The effect of parameter mismatch on the quality of synchronization is also explored.

关键词： synchronization noise time delayt

A Diagnostic Study of the Influence of Early Spring Soil Moisture in Southeastern China on Interannual Variability of the East Asian Subtropical Summer Monsoon Onset

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Journal of Meteorological Research 2023年第1期37卷 45-57页

作者： Zifan ning Renhe ZHANG Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200438 China Meteorological Administration-Fudan University Joint Laboratory of Marine Meteorology Shanghai 200438 Innovation Center of Ocean and Atmosphere System Zhuhai-Fudan Innovation Research InstituteZhuhai 519031 Shanghai Scientific Frontier Base for Ocean-Atmosphere Interaction Studies Fudan UniversityShanghai 200438

The effect of soil moisture(SM)on the onset of East Asian subtropical summer monsoon(EASSM)is investigated based on multiple sets of reanalysis data in the period of 1981–*** is found that the EASSM is characterized by persistent 2-m s^(−1) southerly winds for about 3 months in spring at 850 hPa over the subtropical region of East *** this feature of the meridional winds,we define the EASSM onset date,and obtain that the climatological onset date is pentad 17.7,around 26 *** the interannual timescale,the onset date of EASSM exhibits statistically significant correlation with the SM in southeastern China in the month preceding the onset,with wetter(drier)conditions being associated with later(earlier)*** physical process by which the preceding SM affects the EASSM onset is further explored by examining the surface energy balance as well as its ***(negative)SM anomalies in southeastern China in the month before onset may induce negative(positive)surface temperature *** decreased(increased)surface temperature in southeastern China before the EASSM onset weakens(strengthens)the zonal sea–land thermal contrast in the surface and low-level atmosphere in the subtropical East *** zonal sea–land thermal contrast in wetter(drier)years induces anomalous northerly(southerly)winds over southeastern China,which tends to delay(advance)the zonal thermal seasonal transition in spring and is conducive to a later(earlier)onset of *** results are helpful for understanding and prediction of the variability of EASSM and the EASSM onset.

关键词： soil moisture(SM) East Asian subtropical summer monsoon(EASSM) sea-land thermal contrast onset

Position Optimization for Mobile Relay Communications with Constrained Energy over a Whole Horizontal Plane

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China Communications 2023年第5期20卷 340-350页

作者： Haijun Tan ning Xie Guangdong Key Laboratory of Intelligent Information Processing College of Electronics and Information EngineeringShenzhen UniversityShenzhen 518060China

This paper concerns the position optimization problem of a mobile relay over a whole horizontal *** problem is important because the position of a mobile relay directly affects the end-to-end performance,e.g.,reliability,connectivity,and data *** this paper,we propose a new position optimization scheme of a mobile relay over a whole horizontal plane based on the one-bit feedback information from the destination node,which improves the performance over the prior scheme whose position of the mobile relay is optimized over a fixed *** the proposed scheme,the mobile relay is equipped with merely one single onboard ***,no prior information about the positions of both the source node and the destination node is ***,the proposed scheme can work at low network resources scenario,which is particularly suitable for mobile relay communication with constrained energy,e.g.,the communications in a disaster area where the infrastructure is heavily damaged,volcano monitoring,and wireless powered communication *** to the characteristics of the proposed scheme,we further design two heuristic implementations to calculate the optimal position of a mobile relay over a whole horizontal *** first implementation has better steady performance whereas the second implementation has better convergence *** implement the proposed scheme and conduct an extensive performance comparison between the proposed scheme and prior schemes to verify the advantages of the proposed scheme.

关键词： mobile relay position optimization one bit feedback information whole horizontal plane energy constrained

Syntheses and Crystal Structures of Two Silver(I) Complexes Isolated by the Reaction of [Ag(PPh_3)_2(MeCN)](SbF_6) with a N_6 Ligand

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Chinese Journal of Structural Chemistry 2004年第11期23卷 1277-1281页

作者： MAZhena LINYun CHENZhong-ning StateKeyLaboratoryofStructuralChemistry FujianInstituteofResearchontheStructureofMatterTheChineseAcademyofSciencesFuzhouFujian350002China CentralLaboratory FuzhouUniversityFuzhouFujian350002China

Two silver(I) complexes were obtained by the reaction of a N6 ligand with [Ag(PPh3)2(MeCN)](SbF6). In complex [AgL1(PPh3)](SbF6) 1, the silver center is bound to three N donors of the nitrogen ligand and P donor of one triphenylphosphine group, forming an irregular AgN3P tetrahedron. In complex [Ag(PPh3)4](SbF6) 2, the Ag+ ion is coordinated to four triphenyl- phosphine groups, affording a tetrahedral geometry. Crystal data for complex 1: C30H37AgF6N6PSb, Mr = 856.25, orthorhombic, space group Pbca, a = 19.0702(9), b = 15.9047(7), c = 21.498(1) ?, V = 6520.5(6) ?3, Z = 8, Dc= 1.744 g/cm3, F(000) = 3408, μ = 1.544 mm-1, the final R = 0.0367 and wR = 0.1077 for 5325 observed reflections with I > 2σ(I); and those for 2: C72H60AgF6P4Sb, Mr = 1392.70, trigonal, space group R3, a = 14.4577(6), b = 14.4577(6), c = 51.544(2) ?, V = 9330.5(7) ?3, Z = 6, Dc= 1.487 g/cm3, F(000) = 4224, μ = 0.913 mm-1, the final R = 0.0352 and wR = 0.1089 for 3498 observed reflections with I > 2σ(I).

关键词： coordination crystal structure N6 ligand silver(I) complexes

Virtual Reality:A State-of-the-Art Survey

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International Journal of Automation and computing 2009年第4期6卷 319-325页

作者： ning-ning Zhou Yu-Long Deng School of Computing Nanjing University of Posts and Telecommunications Nanjing 210003 PRC State Key Laboratory of Software Development Environment Beihang University Beijing 100191 PRC

This paper presents a survey on virtual reality systems and provides an in-depth understanding toward the notion of immersion, according to the semantic meanings of the terms ＂virtual＂ and ＂reality＂. The paper analyses the structure and functions of a virtual reality system and takes the three dimensional display as the immersive medium to identify the key issues for construction of virtual environments. The paper also reviews the development of virtual reality technology and introduces new image processing techniques into the design of virtual reality systems and virtual environments.

关键词： Virtual reality immersion virtual reality image processing technology

Planar core based starburst triphenylamine molecules as hole transporting materials for high-performance perovskite solar cells

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Science China Chemistry 2019年第1期62卷 5-6页

作者： Qi Wei Zhijun ning School of Physical Science and Technology Shanghai Tech University

Starburst triphenylamine molecules are generally used as hole transporting materials (HTMs)for optoelectronic devices like solar cells,light emitting diode and field effect transistors .The use of starburst triphenylamine molecules like spiro-OMeTAD HTM initiated the construction of solid state perovskite solar cells (PSCs).Currently,based on triphenylamine HTMs,the highest power conversion efficiency (PCE)of PSCs is up to 22.1%.

关键词： Starburst triphenylamine molecules

Tunable spatial-frequency-shift 3D nanoscopy with chip compatibility overcomes the diffraction limit of the linear optical imaging system

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Science China(Physics,Mechanics & Astronomy) 2021年第9期64卷 125-126页

作者： ning Dai Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083China

The superresolution microscopy that broadens the detection range in the spatial frequency domain through the spatialfrequency-shift(SFS)effect[1-5]shows intriguing advantages including a large field of view,high speed,and good ***,it captures pictures in the wide-field mode and allows a universal implementation without using special fluorophores *** enable the sub-diffraction resolution in the SFS microscopy,it is essential to use the evanescent wave illumination with a large wave vector,which can be built on the integrated photonic configuration,paving the way for a compact nanoscopy on a thin chip[6-8].However,the lack of an approach to actively tune the SFS value in a large range hampers the progress to achieve deep-subwavelength resolution through evanescent illumination with ultra-large wave *** the wave vector of the illumination surpasses twice the cutoff frequency of the objective,a missing band exists between the shifted components and the zeroth component in the spatial frequency domain,which causes severe artifacts and a distortion in the *** a result,the resolution of current linear SFS microscopy has been restricted less than thrice the Abbe diffraction limit of the detection system.

关键词： illumination limit overcome

Tissue cell differentiation and multicellular evolution via cytoskeletal stiffening in mechanically stressed microenvironments

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Acta Mechanica Sinica 2019年第2期35卷 270-274页

作者： Junwei Chen ning Wang Laboratory for Cellular Biomechanics and Regenerative Medicine Department of Biomedical Engineering College of Life Science and Technology Huazhong University of Science and Technology Wuhan 430074 China Department of Mechanical Science and Engineering University of Illinois at Urbana-Champaign Urbana IL 61801 USA

Evolution of eukaryotes from simple cells to complex multicellular organisms remains a mystery. Our postulate is that cytoskeletal stiffening is a necessary condition for evolution of complex multicellular organisms from early simple eukaryotes. Recent findings show that embryonic stem cells are as soft as primitive eukaryotes-amoebae and that differentiated tissue cells can be two orders of magnitude stiffer than embryonic stem cells. Soft embryonic stem cells become stiff as they differentiate into tissue cells of the complex multicellular organisms to match their microenvironment stiffness. We perhaps see in differentiation of embryonic stem cells (derived from inner cell mass cells) the echo of those early evolutionary events. Early soft unicellular organisms might have evolved to stiffen their cytoskeleton to protect their structural integrity from external mechanical stresses while being able to maintain form, to change shape, and to move.

关键词： Cytoskeleton Force Bacteria Amoebae Eukaryotes