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Optimal combination of the correction model and parameters for the precision geometric correction of UAV hyperspectral images

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 173-184页

作者： Wenzhong Tian za Kan Qingzhan Zhao Ping Jiang Xuewen Wang Hanqing Liu College of Mechanical and Electrical Engineering Shihezi UniversityShihezi 832000XinjiangChina Research Center for Space Information Engineering Technology Shihezi 832000XinjiangChina XPCC Division of National Remote Sensing Center of China Shihezi 832000XinjiangChina College of Information Science and Technology Shihezi UniversityShihezi 832000XinjiangChina

Nowadays,with the rapid development of quantitative remote sensing represented by high-resolution UAV hyperspectral remote sensing observation technology,people have put forward higher requirements for the rapid preprocessing and geometric correction accuracy of hyperspectral *** optimal geometric correction model and parameter combination of UAV hyperspectral images need to be determined to reduce unnecessary waste of time in the preprocessing and provide high-precision data support for the application of UAV hyperspectral *** this study,the geometric correction accuracy under various geometric correction models(including affine transformation model,local triangulation model,polynomial model,direct linear transformation model,and rational function model)and resampling methods(including nearest neighbor resampling method,bilinear interpolation resampling method,and cubic convolution resampling method)were ***,the distribution,number,and accuracy of control points were analyzed based on the control variable method,and precise ground control points(GCPs)were *** results showed that the average geometric positioning error of UAV hyperspectral images(at 80 m altitude AGL)without geometric correction was as high as 3.4041 m(about 65 pixels).The optimal geometric correction model and parameter combination of the UAV hyperspectral image(at 80 m altitude AGL)used a local triangulation model,adopted a bilinear interpolation resampling method,and selected 12 edgemiddle distributed *** correction accuracy could reach 0.0493 m(less than one pixel).This study provides a reference for the geometric correction of UAV hyperspectral images.

关键词： geometric correction hyperspectral images unmanned aerial vehicle(UAV) ground control point(GCP)

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Determinants of Satisfaction at Work and Its Reflections on Performance

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Chinese Business Review 2024年第1期23卷 24-36页

作者： Giovani Luiz Garcia Costantini Everton Anger Cavalheiro Larissa Medianeira Bolzan Alejandro Martins Rodrigues Luíza Roloff Falck Federal University of Pelotas PelotasBrazil

This study examines the relationship between job satisfaction and performance,investigating personality traits and satisfaction aspects among employees of a Federal Higher Education Institution.A questionnaire was administered to 658 participants,using structural equation modeling for *** highlighted that challenging work,neuroticism,and self-esteem significantly influenced overall workplace satisfaction,while general satisfaction,self-efficacy,and lack of attention were key determinants of work *** emphasizes the importance for managers to prioritize factors enhancing employee satisfaction,as it positively correlates with job performance.

关键词： satisfaction at work work performance personality traits facets of job satisfaction Federal Higher Education Institution

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Influence of recycled polyethylene terephthalate fibres on plastic shrinkage and mechanical properties of concrete

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Frontiers of Structural and Civil Engineering 2022年第6期16卷 792-802页

作者： NecatÖzaŞIK Özgür erEN Department of Civil Engineering Eastern Mediterranean UniversityMersin 99628Turkey

Polyethylene terephthalate bottles production has drastically increased year after year due to high versatility of polyethylene terephthalate plastics and considerable consumption of *** tandem with that increase,the major concern of society has been the improper disposal of this non-biodegradable material to the *** deal with this concern,recycled polyethylene terephthalate bottles were incorporated in concrete as fibre reinforcements in this *** objective of this research is to evaluate the mechanical properties of recycled polyethylene terephthalate fibre reinforced concrete(RPFRC)in comparison with control concrete without *** terephthalate fibres with three different diameters(0.45,0.65,and 1.0 mm)and two lengths(20 and 30 mm)were added at various proportions(0.5%,1.0%,1.5%and 2.0%)by volume of concrete in order to determine the effect of fibres initially on compressive,flexural and splitting tensile strengths of *** results revealed that none of the fibres have detrimental effects up to 1%volume fraction,however further addition caused slight reductions on mechanical properties in some *** shrinkage resistance and impact resistance tests were also performed according to related *** terephthalate fibres were observed to have marked improvements on those *** a good performance could be attributed primarily to the bridging effect of fibres.

关键词： recycled PET fibre-reinforced concrete mechanical properties plastic shrinkage impact energy

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Shining the shortest flashes of light on the secret life of electrons

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Advanced Photonics 2023年第6期5卷 5-7页

作者： Margarita Khokhlova Emilio Pisanty Amelle zaïr King’s College London Department of PhysicsLondonUnited Kingdom

Ever since the invention of laser pulses,^(1–5)one of the key directions for the development of laser technology has been the creation of ever shorter pulses of *** the past sixty years,improvements in technology have pushed pulse durations down from nanoseconds through picoseconds to femtoseconds,giving us access to time-resolved studies of molecular nuclear motion and chemical reactions.^(6)Just in time for the 59th birthday of the standard(SI)prefixes“femto”and“atto,”^(7)the 2023 Nobel Prize in Physics was awarded to the latest landmark in this effort:the generation of attosecond pulses of light,^(8–10)which opens a window to the most fundamental timescale of the world around us–the timescale of electrons moving inside atoms,molecules,and condensed matter.

关键词： light shortest flash

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基于激光雷达的果园沟型测量平台设计与试验

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农机化研究 2024年第3期46卷 62-69,75页

作者：吴岩峰坎杂戚江涛周馨曌李亚萍石河子大学机械电气工程学院新疆石河子832000 农业部西北农业装备重点实验室新疆石河子832000

针对现有检测开沟质量效率低、精度差等问题,设计了一套由激光雷达、编码器、便携式计算机和支架等构成的非接触式果园开沟宽度深度监测平台,基于编码器获取测量平台前行方向位移,并与上位机软件形成整套采集系统,可快速获取果园沟型三... 详细信息

针对现有检测开沟质量效率低、精度差等问题,设计了一套由激光雷达、编码器、便携式计算机和支架等构成的非接触式果园开沟宽度深度监测平台,基于编码器获取测量平台前行方向位移,并与上位机软件形成整套采集系统,可快速获取果园沟型三维坐标。为了降低外部环境对点云数据处理的影响,采用直通滤波进行果园沟型的有效区域选取,借助MatLab获取其三维点云模型,实现对果园开沟沟形的重构与沟深、沟宽数据的监测。通过重构沟型参数与实测参数对比分析可知:两者宽度相关系数为0.83,均方根误差为0.008,相对误差为2.47%;深度相关系数为0.75,均方根误差为0.009,相对误差为2.76%。研究结果表明:重构沟型参数与实际沟型参数吻合度较高,可精确反映原有沟型形貌特征,为智慧农业果园开沟质量智能检测的构建提供了参考。

关键词：果园激光雷达沟型测量三维重建点云

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Journal of Materials Science & Technology 2022年第1期96卷 248-261页

作者： Seyedmohammad Tabaie Farhad Rézaï-Aria Bertrand C.D.Flipo Mohammad Jahazi Department of Mechanical Engineering École de Technologie Supérieure(ÉTS)H3C 1K3 MontrealQCCanada Institut Clément Ader(ICA) Universitéde ToulouseCNRSIMT Mines AlbiINSAUPSISAECampus Jarlard81013 AlbiFrance TWI Ltd Granta ParkGreat AbingtonCambridge CB216ALUnited Kingdom

The continuous growth in the manufacture of aerospace components such as blisks has led to an increase in the application of different hybrid materials fabricating methods,and thus the requirements for joining and strengthening of dissimilar *** to this goal,selective laser melted(SLM)Inconel718 was joined with forged AD730^(TM)Nickel-based superalloy through linear friction welding(LFW)in this *** variation,specifically with respect to secondary phases precipitation was *** microhardness and strengthening mechanisms of the weldment were also *** precipitation(volume fraction and size of particles)at different regions of both sides of the weld line was *** to the weld line,the dissolution ofγ’/γ"and Laves phases and grain refinement occurred which reveals the effects of both compression strain and high temperature on recrystallization and high degree of elemental diffusion in the weld zone(WZ).It is shown that the size,volume fraction,and shape of secondary phases increased and changed(from spherical to long-striped for Laves particles)as we went from the WZ toward the base ***,the measured microhardness indicated that the strength of AD730^(TM)alloy depends significantly on the grain size,while strength in SLM Inconel 718 was dominated by shape(or size)and the presence of secondary phases(γ’/γ"and Laves).

关键词： Additive manufacturing Linear friction welding Ni-based superalloy Precipitation Microhardness Strengthening mechanisms

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膜杂捆料多级破碎机设计与试验

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农业工程学报 2024年第2期40卷 187-195页

作者：严义其坎杂王吉亮陈绍杰杨崇科李佳莉张炳成严伟哲冯震李亚萍石河子大学机械电气工程学院石河子832000 新疆农垦科学院机械装备研究所石河子832003 石河子开发区锐益达机械装备有限公司石河子832003 绿洲特色经济作物生产机械化教育部工程研究中心石河子832000

针对棉田机收膜杂捆料中膜-土-秆分布不均、相互裹绕且体积过大,无法直接进行有效破碎的问题,通过分析膜杂捆料的破碎过程,确定了一种先破捆、再破碎的破碎方案,并设计了一种包含均匀喂料装置、直刀破捆装置、Y型甩刀破碎装置的膜杂捆... 详细信息

针对棉田机收膜杂捆料中膜-土-秆分布不均、相互裹绕且体积过大,无法直接进行有效破碎的问题,通过分析膜杂捆料的破碎过程,确定了一种先破捆、再破碎的破碎方案,并设计了一种包含均匀喂料装置、直刀破捆装置、Y型甩刀破碎装置的膜杂捆料多级破碎机。以破碎刀辊转速、喂入速度、定刀数量作为主要影响因素,以残膜破碎合格率作为评价指标,进行三因素三水平试验,确定优化参数指标为试验在破碎刀辊转速1 125 r/min;喂入速度为0.012 m/s;定刀数量1个的因素水平下,此时膜杂捆料破碎合格率达到75.15%,满足后续加工工艺要求。该装置的研究对残膜资源化利用关键技术问题具有重要意义和应用价值。

关键词：农业机械试验残膜资源化利用膜杂捆料破碎机器

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Calibration and test of the contact parameters for chopped cotton stems based on discrete element method

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International Journal of Agricultural and Biological Engineering 2022年第5期15卷 1-8,F0003页

作者： Rongqing Liang Xuegeng Chen Bingcheng Zhang Xinzhong Wang za Kan Hewei Meng College of Mechanical and Electrical Engineering Shihezi University Shihezi 832000XinjiangChina Engineering Research Center for Production Mechanization of Oasis Special Economic Crop Ministry of EducationShihezi 832000XinjiangChina School of Agriculture Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

In view of the fact that the existing cotton stem simulation models are simplified and have a large discrepancy from the actual appearance and the contact parameters have not been *** this study,the simulation model and numerical simulation were established using the discrete element software *** a second-order response model between contact parameters and repose angle had been *** test result showed that the static friction coefficient,rolling friction coefficient,and coefficient of restitution between cotton stems were crucial factors affecting the repose *** determination coefficient corrected determination coefficient and p-value of the second-order response model were R^(2)=0.959,R^(2)_(adj)=0.921,and perror values of the comparison between the simulation test results and the corresponding physical test values were all less than 10%,which showed that the model was reliable and had high interpretation and predictability,this study can provide a certain theoretical basis and data support for the setting of contact parameters in the data simulation of cotton stem harvesting and processing,mechanically-harvested film residue crushing and film stem separation,etc.

关键词： discrete element method cotton stem repose angle contact parameters calibration

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Calibration of the simulation parameters of jujubes in dwarfing and closer cultivation in Xinjiang during harvest period

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International Journal of Agricultural and Biological Engineering 2022年第2期15卷 256-264页

作者： Shiqi Yao Gaokun Shi Baoshuai Wang Huijie Peng Hewei Meng za Kan College of Mechanical Electrical Engineering Shihezi UniversityShihezi 832000XinjiangChina Key Laboratory of Northwest Agricultural Equipment Ministry of Agriculture and Rural AffairsShihezi 832000XinjiangChina

order to obtain accurate contact parameters of jujubes in dwarfing and closer cultivation in Xinjiang during the harvest period,based on the Hertz-Mindlin(no-slip)contact model in EDEM,the contact parameters,including the coefficient of restitution,static friction,and rolling friction,between jujube and machine components have been calibrated through physical and simulation *** coefficient of restitution,static friction,and rolling friction between the jujubes and steel(jujube-steel)were calculated as 0.33,0.46,and 0.04,*** coefficient of restitution,static friction,and rolling friction between the jujubes and polyvinyl chloride(PVC)(jujube-PVC)were calculated as 0.39,0.61,and 0.06,*** optimum contact parameters among jujubes(inter-jujubes)were 0.23,0.33,and *** accumulation test was applied for comparing the simulation and testing values of jujube’s repose *** the results,the relative error was 1.27%which means the discrete element model and the contact parameters of jujube can be used for the discrete element simulation *** addition,the results can be adequately used to simulate particle scale mechanics(grain commingling,flow/motion,forces,etc.)of jujube in harvest as well as the design and working mechanism study of post-harvest processing machinery and devices.

关键词： jujube EDEM contact parameter experiment calibration

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Cotton stalk restitution coefficient determination tests based on the binocular high-speed camera technology

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International Journal of Agricultural and Biological Engineering 2022年第4期15卷 181-189页

作者： Bingcheng Zhang Xuegeng Chen Rongqing Liang Jiali Li Xinzhong Wang Hewei Meng za Kan College of Mechanical and Electrical Engineering ShiHezi University Shihezi 832000XinjiangChina School of Agriculture Engineering Jiangsu University Zhenjiang 212013JiangsuChina Engineering Research Center for Production Mechanization of Oasis Special Economic Crop Ministry of EducationShihezi 832000China

The restitution coefficient(RC)of cotton stalks is an important elementary physical parameter that is required to establish the crushing mechanical model and research the film residue separation *** this study,the calculation method of restitution coefficient considering the rotation motion of stalk-shaped agricultural materials was derived based on the principle of kinematics and the energy restitution coefficient method,and a test bench for measuring the RC was designed and *** effects of collision material,moisture content,length,diameter,release height,and collision angle respectively on the RC were investigated by single-factor experiments and orthogonal experiments,and the regression models between influence factors and the RC were *** results showed that Q235 showed the highest value of the RC,and it was followed by cotton stalks and soil lumps,*** RC of cotton stalks decreased with the increase of moisture content and diameter,while it increased at first and then decreased with the increase of *** the release height was less than 500 mm,the RC increased with the increased release *** the collision angle was less than 40°,the RC showed a linear increasing *** significance of the effects of factors on RC decreased with the following sequence:collision angle,length,release height,diameter,and moisture ***,collision angle,and release height were extremely *** contrast test results showed that the values based on Newton’s restitution coefficient method were smaller than that based on the energy restitution coefficient *** verification test showed that the predicted rebound height of cotton stalks calculated based on the energy restitution coefficient method was closer to the actual rebound height,and the relative error was less than 5%.

关键词： high-speed camera technology cotton stalk collision restitution coefficient determination test

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