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Digital twins in smart farming:An autoware-based simulator for autonomous agricultural vehicles

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International Journal of Agricultural and Biological Engineering 2023年第4期16卷 184-189页

作者： Xin Zhao Wanli Wang long Wen Zhibo Chen Sixian Wu Kun Zhou Mengyao Sun Lanjun Xu Bingbing Hu Caico.g Wu co.lege of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China Key Laboratory of Agricultural Machinery Monitoring and Big Data Application Ministry of Agriculture and Rural AffairsBeijing 100083China The Bureau of Agriculture and Rural Affairs of Urumchi Xinjiang Uygur Autonomous RegionUrumchi 830000China Research&Advanced Engineering AGCO A/SDK-8930 RandersDenmark beijing Agricultural Machinery Experiment Appraisal Extension Station Beijing 100079China Kunlun Beidou Intelligence Technologies co.ltd. Beijing 102200China

Digital twins can improve the level of co.trol over physical entities and help manage co.plex systems by integrating a range of *** autonomous agricultural machine has shown revolutionary effects on labor reduction and utilization rate in field *** vehicles in precision agriculture have the potential to improve co.petitiveness co.pared to current crop production methods and have beco.e a research ***,the development time and resources required in experiments have limited the research in this *** tools in unmanned farming that are required to enable more efficient,reliable,and safe autonomy are increasingly *** by the recent development of an open-source virtual simulation platform,this study proposed an autoware-based simulator to evaluate the performance of agricultural machine guidance based on digital *** photogrammetry using drones is used to co.struct threedimensional maps of fields at the same scale as reality.A co.munication format suitable for agricultural machines was developed for data input and output,along with an inter-node co.munication *** co.version,publishing,and maintenance of multiple co.rdinate systems were co.pleted based on ROS(Robot Operating System).co.erage path planning was performed using hybrid curves based on Bézier curves,and it was tested in both a simulation environment and actual fields with the aid of Pure Pursuit algorithms and PID co.trollers.

关键词： autoware simulation platform autonomous agricultural vehicle digital twin autonomous robots

Retinal neovascularization induced by mutant Vldlr gene inhibited in an inherited retinitis pigmentosa mouse model:an in-vivo study

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International Journal of Ophthalmology(English edition) 2021年第7期14卷 990-997页

作者： Wei-Ming Yan Pan long Mei-Zhu Chen Dong-Yu Wei Jian-co.g Wang Zuo-Ming Zhang Lei Zhang Tao Chen Department of Ophthalmology the 900^(th)Hospital of Joint Logistic Support Forceo of PLA(Clinical Medical College of Fujian Medical UniversityDongfang Hopsital Affiliated to Xiamen University)Fuzhou 350025Fujian ProvinceChina Center of Clinical aerospace Medicine Air Force Medical UniversityXi’an 710032Shaanxi ProvinceChina Department of Ophthalmology the West General Hospital of Chinese PLAChengdu 610083Sichuan ProvinceChina beijing HealthOLight technology co. Ltd.Beijing 10010China Shaanxi Eye Hospital Xi’an People’s Hospital(Xi’an Fourth Hospital)Affiliated Guangren HospitalSchool of MedicineXi’an Jiaotong UniversityXi’an 710004Shaanxi ProvinceChina

AIM:To explore whether the retinal neovascularization(NV)in a genetic mutant mice model co.ld be ameliorated in an inherited retinitis pigmentosa(RP)mouse,which would help to elucidate the possible mechanism and prevention of retinal NV diseases in ***:The Vldlr^(-/-)mice,the genetic mutant mouse model of retinal NV caused by the homozygous mutation of Vldlr gene,with the rd1 mice,the inherited RP mouse caused by homozygous mutation of Pde6b gene were *** of the above two mice led to the birth of the F1 hybrids,further inbreeding of which gave birth to the F2 *** ocular genotypes and phenotypes of the mice from all generations were examined,with the F2 offspring grouped acco.ding to the ***:The rd1 mice exhibited the RP phenotype of outer retinal degeneration and loss of retinal *** Vldlr^(-/-)mice exhibited the phenotype of retinal NV obviously shown by the fundus fluorescein *** F1 hydrides,with the heterozygote genotype,exhibited no phenotypes of RP or retinal *** F2 offspring with homozygous genotypes were grouped into four *** were the F2-Ⅰmice with the wild-type Pde6b and Vldlr genes(Pde6b~(+/+)-Vldlr~(+/+)),which had normal ocular phenotypes;the F2-Ⅱmice with homozygous mutant Vldlr gene(Pde6b~(+/+)-Vldlr^(-/-)),which exhibited the retinal NV phenotype;the F2-Ⅲmice with homozygous mutant Pde6b gene(Pde6b^(-/-)-Vldlr~(+/+)),which exhibited the RP ***,the F2-Ⅳmice with homozygous mutant Vldlr and Pde6b gene(Pde6b^(-/-)-Vldlr^(-/-))showed only the RP phenotype,without the signs of retinal ***:The retinal NV can be inhibited by the RP phenotype,which implies the role of a hyperoxic state in treating retinal NV diseases.

关键词： retinitis pigmentosa retinal neovascularization Pde6b gene Vldlr gene photoreceptor

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2219铝合金激光-电弧复合焊接工艺优化

航天制造技术 2024年第1期 16-21页

作者：张正浩刘天亮刘云婷汤莹莹龙莹莹郭盛斌首都航天机械有限公司北京100076

本研究采用co.(2)激光-TIG电弧复合焊接方法对航天用2219铝合金开展了焊接工艺优化试验,研究了激光功率、焊接电流、焊接速度等参数对焊接接头成形的影响,得到了优化的co.(2)激光-TIG复合焊接参数,同时对优化焊接参数下焊接接头的显微... 详细信息

本研究采用co.(2)激光-TIG电弧复合焊接方法对航天用2219铝合金开展了焊接工艺优化试验,研究了激光功率、焊接电流、焊接速度等参数对焊接接头成形的影响,得到了优化的co.(2)激光-TIG复合焊接参数,同时对优化焊接参数下焊接接头的显微组织和力学性能进行了分析。焊缝中心区域组织主要为Al-Al_(2)Cu组成的共晶组织,形态上为细小的枝状晶,热影响区组织与母材组织近似,但是晶粒尺寸略大于母材。复合焊接接头平均抗拉强度为294 MPa,达到母材抗拉强度的70.84%,断后延伸率为8%,拉伸断裂特征为典型的韧性断裂。

关键词：复合焊接 2219铝合金工艺优化

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9自由度主动悬架平顺性研究

北京理工大学学报 2019年第10期39卷 1012-1017页

作者：潘成龙荣吉利项大林郑育龙北京理工大学宇航学院北京100081 北京宇航系统工程研究所北京100076 中车长春轨道客车股份有限公司吉林长春130000

基于汽车系统动力学理论,利用拉格朗日定理,推导设备-车-路耦合的9自由度主动悬架动力学方程,采用滤波白噪音作为左右车轮随机路面不平度激励,根据最优控制原理设计LQR控制器,建立主动悬架控制仿真模型.采用自适应粒子群算法优化加权系... 详细信息

基于汽车系统动力学理论,利用拉格朗日定理,推导设备-车-路耦合的9自由度主动悬架动力学方程,采用滤波白噪音作为左右车轮随机路面不平度激励,根据最优控制原理设计LQR控制器,建立主动悬架控制仿真模型.采用自适应粒子群算法优化加权系数Q,将主动悬架的设备加速度等性能参数均方根值与被动悬架进行对比分析.仿真结果表明:采用自适应粒子群算法优化LQR控制方法,能够显著改善车辆平顺性,保护车载设备可靠性.

关键词：汽车主动悬架线性二次型控制器粒子群算法平顺性

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中频辅助变流器半实物仿真研究

机车电传动 2021年第2期 73-78页

作者：程龙中国铁道科学研究院集团有限公司机车车辆研究所北京100081 北京纵横机电科技有限公司北京100094

轨道交通车辆使用的中频辅助变流器采用LLC谐振变换器和中频变压器替代传统工频变压器,可提高变流器的开关频率和减小磁性元件的体积与重量。为提高辅助控制单元(ACU)的设计和验证手段,对中频辅助变流器半实物仿真进行研究,建立了中频... 详细信息

轨道交通车辆使用的中频辅助变流器采用LLC谐振变换器和中频变压器替代传统工频变压器,可提高变流器的开关频率和减小磁性元件的体积与重量。为提高辅助控制单元(ACU)的设计和验证手段,对中频辅助变流器半实物仿真进行研究,建立了中频辅助变流器的电路模型;通过实时仿真系统、信号处理系统、数据采集系统、ACU和上位机搭建了半实物仿真系统;通过半实物仿真结果与实际试验结果的对比验证了该仿真系统的正确性和有效性。

关键词：中频辅助变流器高速动车组城市轨道车辆谐振变换器半实物仿真

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建筑-交通-能源(BVG)融合的探索应用

建设科技 2024年第7期 41-45页

作者：李任戈殷帅吴晓晨路则耀龙东风高微刘扬凡培红中建科工集团有限公司深圳518054 住房和城乡建设部科技与产业化发展中心北京100835

随着国家双碳战略的推进,建筑、交通、能源等行业的绿色化、低碳化转型稳步推进。建筑-交通-能源(BVG)融合发展,为建筑行业的低碳化发展提供了前所未有的发展机遇。本文以惠州中建科工绿色科技零能耗办公楼为例,进行了具体的分析与判断... 详细信息

随着国家双碳战略的推进,建筑、交通、能源等行业的绿色化、低碳化转型稳步推进。建筑-交通-能源(BVG)融合发展,为建筑行业的低碳化发展提供了前所未有的发展机遇。本文以惠州中建科工绿色科技零能耗办公楼为例,进行了具体的分析与判断。结果显示,光储直柔及建筑-交通-能源(BVG)融合发展,可以降低建筑碳排放,具有重要的意义。

关键词：建筑-交通-能源(BVG)融合既有建筑改造零碳建筑

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重塑黏土压缩变形参数研究

低温建筑技术 2024年第7期46卷 139-142页

作者：苏铁志王一鸣朱首金龙奇航周佳欣向婷王理杰航天规划设计集团有限公司北京100162 成都工业职业技术学院成都610000 山东科技大学土木工程与建筑学院山东青岛266590 长江师范学院建筑物全生命周期健康检测与灾害防治工程研究中心重庆涪陵408100

土体压缩变形参数是地基沉降计算的基础,可通过室内一维固结试验获得,由于试验过程耗时长,给出土体压缩变形参数与土体物理指标的经验关系具有重要工程意义。文中通过对6种重塑黏土开展一维压缩试验,测定土体的压缩变形指标,对它与土体... 详细信息

土体压缩变形参数是地基沉降计算的基础,可通过室内一维固结试验获得,由于试验过程耗时长,给出土体压缩变形参数与土体物理指标的经验关系具有重要工程意义。文中通过对6种重塑黏土开展一维压缩试验,测定土体的压缩变形指标,对它与土体的物理力学性质指标相关性进行分析。结果表明重塑黏土饱和状态下所能保持的最大含水率、液塑限与土体的压缩指数有良好的相关性,通过建立经验方程,可以根据土体物理力学指标较好地推算重塑黏土的压缩变形参数。

关键词：一维固结试验压缩指数最大饱和含水率重塑黏土

Influence of the sparsity of random speckle illumination on ghost imaging in a noise environment

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Chinese Optics Letters 2021年第4期19卷 17-21页

作者： long Pan Chenjin Deng Cuiping Yu Shuai Yue Wenlin Gong Shensheng Han Key Laboratory for Quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Wuhan Optics Valley aerospace Sanjiang Laser Industrial technology Research Institute co. Ltd.Wuhan 430075China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China

The influence of the sparsity of random speckle illumination on traditional ghost imaging(GI) and GI via sparsity co.straint(GISC) in a noise environment is investigated. The experiments demonstrate that both GI and GISC obtain their best imaging quality when the sparsity of random speckle illumination is 0.5, which is also explained by some parameters such as detection of the signal to noise ratio and mutual co.erence of the measurement matrix.

关键词： ghost imaging sparsity speckle illumination noise environment

Ground- and Space-Based Observation of Kordylewski Clouds

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Space(Science & technology) 2021年第1期2021卷 299-308页

作者： Peng Wang Xiao-Jun Jiang Xi-Yun Hou Li-Hua Zhang Li-Xiang Jiang Jia-Qi Wang Hui Zhi Zi-long Jiao Tao Li Ming-He Liu Jian-Feng Wang DFH Satellite co. Ltd.Beijing 100094China School of aerospace Engineering Beijing Institute of TechnologyBeijing 100081China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100101China Nanjing University Nanjing 210023China beijing Institute of Spacecraft Environment Engineering Beijing 100094China

The ghost dust clouds in the vicinity of Earth-Moon triangular libration points are known as the“Kordylewski clouds”(KDCs).Objects in the KDCs may give hints to the physical,chemical,and dynamical properties of the solar *** a result,in situ exploration of the KDCs can help us understand the evolution of our solar *** paper first summarizes the observation history of the *** on the properties of the KDCs,a ground-and space-based observation co.cept is proposed,using the CAST 100 platform developed by DFH and ground *** details of the co.cept are exploited.

关键词： ghost system details