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Journal of Earth Science 2023年第2期34卷 297-303页

作者： Wenkai Chen gang rao Dengjie Kang Zhifan Wan Dun Wang Lanzhou Institute of Seismology China Earthquake AdministrationLanzhou730000China School of Geoscience and Technology Southwest Petroleum UniversityChengdu610500China State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of GeosciencesWuhan430074China

INTRODUCTION,At 01:17 UTC(04:17 on local time)on Feb.6,2023,a devastating earthquake with a moment magnitude(Mw)7.8 occurred in the Gaziantep,southern Turkey.The earthquake was located at 37.174°N and 37.032°E,with ... 详细信息

关键词： earthquake magnitude Earthquake

Relationship between Landslides and Active Normal Faulting in the Epicentral Area of the AD 1556 M～8.5 Huaxian Earthquake,SE Weihe Graben(Central China)

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Journal of Earth Science 2017年第3期28卷 545-554页

作者： gang rao Yali Cheng Aiming Lin Bing Yan School of Earth Sciences Zhejiang University Department of Geophysics Graduate School of Science Kyoto University School of Earth Sciences and Engineering Nanjing University

In this paper, we focus on the characteristics of the landslides developed in the epicentral area of AD 1556 M^8.5 Huaxian Earthquake, and discuss their relations to the active normal faults in the SE Weihe Graben, Central China. The results from analyzing high-resolution remote-sensing imagery and digital elevation models（DEMs）, in combination with field survey, demonstrate that：（i） the landslides observed in the study area range from small-scale debris/rock falls to large-scale rock avalanches;（ii） the landslides are mostly developed upon steep slopes of ≥30°; and（iii） the step-like normal-fault scarps along the range-fronts of the Huashan Mountains as well as the thick loess sediments in the Weinan area may facilitate the occurrence of large landslides. The results presented in this study would be helpful to assess the potential landslide hazards in densely-populated areas affected by active normal faulting.

关键词： landslides active normal faults Huaxian Earthquake Weihe Graben Ordos Block

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舀种勺舌式胡麻精量穴播器设计与试验

农业机械学报 2024年第3期55卷 85-95页

作者：李辉赵武云石林榕戴飞饶罡王尊甘肃农业大学机电工程学院兰州730070

针对胡麻播种机用种量大、播量变异系数大、播种不均匀的问题,基于胡麻种子物理特性和种植农艺要求,设计一种舀种勺舌式胡麻精量穴播器。通过分析穴播器工作原理确定穴播器组成、舀种勺结构参数范围及安装数量;对舀种勺舀种过程和清种... 详细信息

针对胡麻播种机用种量大、播量变异系数大、播种不均匀的问题,基于胡麻种子物理特性和种植农艺要求,设计一种舀种勺舌式胡麻精量穴播器。通过分析穴播器工作原理确定穴播器组成、舀种勺结构参数范围及安装数量;对舀种勺舀种过程和清种过程进行力学分析,确定穴播器角速度范围;通过EDEM仿真过程得知,花纹内壁聚种斜槽在不影响舀种勺填充效果的同时,不仅可以提高仿真效率,还可以增大种子流动性,便于舀种勺充种。以穴播器角速度、舀种勺顶端过渡圆角半径、种室隔离板高度为试验因素,穴播器排种合格率、漏播率和重播率为试验指标,利用EDEM离散元仿真软件开展二次旋转正交组合试验,得到最优参数组合为:穴播器角速度2.9 rad/s、舀种勺顶端过渡圆角半径2.5 mm、种室隔离板高6.8 mm;将该舀种勺3D打印制作进行排种性能试验验证,台架试验得到该舀种勺排种合格率、漏播率和重播率平均值分别为87.00%、6.33%、6.67%;田间试验得到该舀种勺排种合格率为88.33%,漏播率为6.67%,重播率为5.00%;胡麻平均种植密度为50株/m^(2),其台架试验与田间试验结果基本一致,性能满足胡麻精量播种农艺要求。

关键词：胡麻精量穴播器舀种勺 EDEM

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YOLOv5s-CBAM算法在福寿螺虫卵识别中的应用分析

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中国农机化学报 2024年第6期45卷 223-228页

作者：黄尧何敬付饶刘刚林远杨成都理工大学地球科学学院成都市610059 地质灾害防治与地质环境保护国家重点实验室(成都理工大学) 成都市610059

福寿螺是我国重点关注的入侵物种,对农作物生长和生态环境会造成不利影响。及时获取福寿螺虫卵的分布信息,对于提前防治其入侵能起到有效的帮助作用。基于YOLOv5s基础网络模型,引入CBAM(Convolutional Block Attention Module)注意力机... 详细信息

福寿螺是我国重点关注的入侵物种,对农作物生长和生态环境会造成不利影响。及时获取福寿螺虫卵的分布信息,对于提前防治其入侵能起到有效的帮助作用。基于YOLOv5s基础网络模型,引入CBAM(Convolutional Block Attention Module)注意力机制模块,以提高在复杂的自然环境下对福寿螺虫卵特征信息的提取,提出YOLOv5s-CBAM模型进行福寿螺虫卵识别方法。试验结果表明,引入CBAM的识别效果要好于引入CA和SE注意力模块。同时,引入CBAM的YOLOv5s-CBAM模型,识别效果优于原基础YOLOv5s模型,一定程度上能够克服倒影、植物遮挡等因素干扰。且平均精度均值达到83.8%,相比原模型提升2.5个百分点。基于深度学习的方法对复杂自然环境中的福寿螺虫卵进行识别是切实可行的,为福寿螺等入侵物种的监测防控提供新的思路。

关键词：深度学习 YOLOv5s算法注意力机制福寿螺虫卵图像识别

Finite Element Analysis on Loosing Causation of Connecting Bolts to Fix Main Trolley Rails

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Finite Element Analysis on Loosing Causation of Connecting B...

The evolution of courtship displays in Galliformes

2005国际机械工程与力学会议

作者： gang rao College of Machinery ＆ Automation Wuhan University of Science and Technology

In a certain steel making plant, one casting crane was mended to increase its main lifting capacity from 160t to 180t. To support 180t lifting load, main trolley was rebuilt and two main girders were mended. The casting crane could work normally, before its main lifting capacity was increased. After it was mended, connecting bolts to fix main trolley rails were often loosing. If the pretightening force was increased, girth welds to fix bolts were often ruptured. In order to solve these problems, the root causation must be found. In this paper, finite element analysis is applied to aiding this research. Connecting bolts to fix main trolley rails and girth welds to fix bolts are selected as main researching objects of FEA. They are studied within girders system, and special load conditions of this crane are considered carefully. By FEA, an inversion is used to determine pretightening force of bolts in girders system before and after the increasing of main lifting capacity of this crane. After FEA results of bolts and its girth welds are carefully analyzed, root causations of loosing of bolts and rupture of girth welds are found. Finally, a method to solve these problems is offered to ensure this crane working safely.

关键词： Casting crane Loosing of bolt FEA Inversion

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Avian Research 2022年第1期13卷 11-16页

作者： Xiyuan Guan Xiaodong rao gang Song Daiping Wang Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing100101China College of Forestry/Wuzhishan National Long Term Forest Ecosystem Monitoring Research Station Hainan UniversityHaikou570228China Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing100101China

Species in Galliformes have elaborate ritual courtship displays,often including strutting,fluffing of tail or head feathers,and vocal sounds that serve as excellent examples of sexual selection.According to the male orientation to the female while either posturing or moving,these courtship displays of gallinaceous species can be classified into three categories:1)‘frontal displays’,2)‘lateral displays’,and 3)‘both frontal and lateral displays’.Questions regarding which category of displays is the ancestral state and the evolutionary history of courtship displays in Galliformes remain unanswered.We collected and classified 131 species in terms of their courtship displays into the three categories listed above and carried out a large-scale comparative analysis to reveal the evolutionary trajectory of this trait.We found that the ancestral state of courtship displays of Galliformes involves both relatively short and straightforward frontal and lateral elements(i.e.,the category of‘both frontal and lateral displays’).Furthermore,ancestral trait reconstructions suggest that transitions from‘lateral displays’to‘frontal displays’occurred more frequently than the other way around(i.e.,from‘frontal displays’to‘lateral displays’).In addition,some transitions occurred from‘both frontal and lateral displays’to‘lateral displays’but not from‘both frontal and lateral displays’to‘frontal displays’.Ancestral state reconstruction of courtship displays at the root of the Galliformes phylogeny supports the‘both frontal and lateral displays’first scenario.This original state then evolved towards two extremes,either‘frontal displays’or‘lateral displays’,with more complicated and elaborate display components.Moreover,subsequent transitions occurred from‘lateral displays’to‘frontal displays’much more frequently than the other way around during the evolutionary history,indicating positive selection of‘frontal displays’.

关键词： Ancestral state analysis Comparative studies Courtship displays Galliformes Sexual selection Transition rate analysis

基于DEM-MBD耦合的滚勺式精量穴播器成穴器运动参数优化

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中国农业大学学报 2024年第1期29卷 66-77页

作者：王尊赵武云石林榕孙步功孙伟戴飞周刚郭军海饶罡李辉甘肃农业大学机电工程学院兰州730070 甘肃省农科院旱地农业研究所兰州730070

针对滚勺式精量穴播器固定成穴器成穴轨迹呈余摆线,余摆线过大造成撕膜和挑膜的问题,同时为降低株距的差异性,基于离散元法和多体动力学耦合方法对穴播器成穴器运动过程进行仿真分析。以牵引速度、牵引角度和穴播器质量为影响因素,以余... 详细信息

针对滚勺式精量穴播器固定成穴器成穴轨迹呈余摆线,余摆线过大造成撕膜和挑膜的问题,同时为降低株距的差异性,基于离散元法和多体动力学耦合方法对穴播器成穴器运动过程进行仿真分析。以牵引速度、牵引角度和穴播器质量为影响因素,以余摆线宽度、株距和播种深度为响应值,通过预试验和单因素试验确定各因素对响应值的影响规律,基于前期仿真试验结果开展多因素仿真试验获得最优参数组合,并通过田间试验验证最优结果的可靠性。结果表明:滚勺式精量穴播器成穴器运动的最优参数组合为,牵引速度523.43 mm/s、牵引角度21.9°、穴播器质量18.2 kg,此时株距为196.84 mm,余摆线宽度13.98 mm。以最优参数组合进行验证试验,株距为193.86 mm,相对误差1.51%;余摆线宽度13.28 mm,其相对误差4.39%。

关键词：穴播器成穴器 DEM-MBD耦合仿真优化

基于电光聚合物薄膜的芯片式光学硅基电场传感器传感及温度特性研究

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高压电器 2024年第4期60卷 65-71页

作者：饶宇飞魏诗超刘阳刘景轩李海峰梁纲杨庆陈柠国网河南省电力公司电力科学研究院郑州450000 河南诺盾科技有限公司郑州450000 重庆大学电气工程学院重庆400000

“双碳”背景下,新型电力系统的数字化转型对电力传感技术提出了更高的要求。文中针对光学电场传感器温度稳定性差的问题,提出了基于电光聚合物薄膜的芯片式光学硅基电场传感器。首先介绍了电光效应原理,电光聚合物的2阶非线性光学效应... 详细信息

“双碳”背景下,新型电力系统的数字化转型对电力传感技术提出了更高的要求。文中针对光学电场传感器温度稳定性差的问题,提出了基于电光聚合物薄膜的芯片式光学硅基电场传感器。首先介绍了电光效应原理,电光聚合物的2阶非线性光学效应以及电光能量耦合方法,其次设计了传感器的加工流程并完成了制备,同时在敏感芯片上成功涂覆电光聚合物,最后通过搭建实验测试平台,完成了传感器的线性度、交流响应以及温度特性测试。实验结果表明,所制备的光学电场传感器在工频电场下拥有较好的线性度且灵敏度高达0.945 mV·(kV·m^(-1))^(-1),传感器在0~75℃温度范围内输出幅值及相位稳定,其幅值比最大波动为0.481 dB,相位差最大为3.82°。文中提出的传感结构切实可行地提升了光学硅基集成电场传感器的温度特性,为硅基集成光学电场传感器在电力系统中的使用提供参考方案。

关键词：电光聚合物光学芯片电场传感器温度特性

Holocene aeolian stratigraphic sequences in the eastern portion of the desert belt(sand seas and sandy lands) in northern China and their palaeoenvironmental implications

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Science China Earth Sciences 2019年第8期62卷 1302-1315页

作者： Xiaoping YANG Peng LIANG Deguo ZHANG Hongwei LI Patrick RIOUAL Xulong WANG Bing XU Zhibang MA Qianqian LIU Xiaozong REN Fangen HU Yuxin HE gang rao Ninghua CHEN Department of Geography School of Earth SciencesZhejiang UniversityHangzhou310027China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing100049China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an710061China Institute of Chinese Historical Geography Fudan UniversityShanghai200433China School of Geography Taiyuan Normal UniversityTaiyuan030619China College of Teachers’Education Yichun UniversityYichun336000China Department of Geology School of Earth SciencesZhejiang UniversityHangzhou310027China

This paper presents the environmental history and its responses to palaeoclimatic changes since the start of the Holocene in the eastern portion of the desert belt(sand seas and sandy lands) in northern China by comparing the aeolian sandpalaeosol sequences and their palaeoclimatic proxies. The optically stimulated luminescence(OSL) ages of the aeolian sandpalaeosol sedimentary sequences and a series of palaeoenvironmental proxies show that:(1) The large-scale dune landscape currently in the Kubuqi Sand Sea was formed during the Holocene in general;and the palaeosol was generally developed during the period of 4–2 ka, indicating conditions favorable for vegetation growth, soil development, and organic carbon accumulation due to increased precipitation or effective moisture and weakened aeolian activities;the large-scale expansion of dunes in the recent 2 ka is closely linked to human activities. The variable discharge of the Yellow River with diversions for irrigation may have resulted in a more consistent supply of aeolian particles for dune field expansion.(2) The dune landscape of the Hunshandake Sandy Land was likely formed around 12 ka, and before this, the western part of the Hunshandake Sandy Land would have been covered by a single large lake;it was obviously wetter than today in the sandy land during the period of 9.6–3 ka and the palaeosols were developed at the same time. But the aeolian activities have not been completely dormant in this long-lasting wetter epoch;because the Holocene wetter period was likely time-transgressive across the region.(3) The palaeosol of the Hulunbuir Sandy Land began to develop as early as 14.5 ka, probably continuing until the last 2 ka. The palaeosol development of various dune fields in the eastern portion of the desert belt(sand seas and sandy lands) in northern China is spatially heterogeneous, and even the palaeosol development time in different locations within each sandy land is inconsistent. During the middle Holocene(especially the 7.5–3.5 ka), all the sandy land

关键词： Sand sea Sandy land,Environmental evolution,Kubuqi,Hunshandake,Hulunbuir

基于各向异性热导率设置的选区激光熔化成形过程仿真分析

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武汉科技大学学报 2024年第2期47卷 122-128页

作者：张万饶刚陈浩东熊琦王东烁刘昌明武汉科技大学冶金装备及其控制教育部重点实验室湖北武汉430081 武汉科技大学机械自动化学院湖北武汉430081 武汉科技大学机械传动与制造工程湖北省重点实验室湖北武汉430081

针对选区激光熔化(SLM)工艺下零件中高残余应力问题,同时考虑到打印过程中熔池对流效应,本文通过设置各向异性热导率材料参数,利用有限元方法对Inconel 718合金粉末SLM成形过程中的温度场和应力场进行模拟,分析了基板预热温度对成形件... 详细信息

针对选区激光熔化(SLM)工艺下零件中高残余应力问题,同时考虑到打印过程中熔池对流效应,本文通过设置各向异性热导率材料参数,利用有限元方法对Inconel 718合金粉末SLM成形过程中的温度场和应力场进行模拟,分析了基板预热温度对成形件残余应力的影响。结果表明,选择合适的各向异性热导率增强系数可显著提升温度场的仿真精度,并且越靠近热源中心区域,温度梯度越大;在应力方面,高应力区域集中分布于成形件上表面,最大残余应力位于成形件与基板的交界处,此处易发生开裂变形;采用基板预热方式能改善成形件中残余应力分布,随着预热温度提升,最大残余应力降低,成形件上表面高应力分布区域减小。

关键词：选区激光熔化 Inconel 718合金各向异性热导率熔池尺寸基板预热残余应力仿真分析