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基于YOLOv5的倒地检测

吉林大学学报（信息科学版） 2024年第2期42卷 378-386页

作者：何乐华谢光珍刘柯翔吴宁张浩澜张忠睿吉林大学通信工程学院长春130012

为提高传统目标检测的识别效果和准确率,并加快运算速度,提出了一种具有更强大特征学习和特征表达能力的卷积神经网络(CNN:Convolutional Neural Network)模型和相关的深度学习训练算法,并将其应用于计算机视觉领域的大规模识别任务。... 详细信息

为提高传统目标检测的识别效果和准确率,并加快运算速度,提出了一种具有更强大特征学习和特征表达能力的卷积神经网络(CNN:Convolutional Neural Network)模型和相关的深度学习训练算法,并将其应用于计算机视觉领域的大规模识别任务。首先详细分析了传统目标检测算法,如V-J(Viola-Jones)检测器、 HOG(Histogram of Oriented Gradients)特征结合SVM(Support Vector Machine)分类器和DPM(Deformable Parts Model)检测器的特点。然后提出了深度学习算法,如RCNN(Region-based Convolutional Neural Networks)算法和YOLO(You Only Look Once)算法,并分析了其在目标检测任务中的应用现状。针对倒地检测任务,使用YOLOv5(You Only Look Once version 5)模型对不同身高体型目标人群的行为进行训练。通过使用不同的交并比(IOU:Intersection over Union)、准确率(Precision,P)、召回率(Recall,R)和PR曲线等评估指标,对YOLOv5模型进行了分析,评估了其在检测站立和倒地两种活动方式的实际效果。同时通过预训练和增强处理,增加了训练样本数量并提高了网络的识别准确率。实验结果表明,倒地识别率达到了86%。可将其应用于灾区探测救援类机器人的设计中,以辅助识别和分类受伤倒地人员,提高灾区救援效率。

关键词：目标检测卷积神经网络 YOLO模型计算机视觉深度学习

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桑椹化学成分与药理作用研究进展

中草药 2024年第15期55卷 5274-5285页

作者：韩非若李婷阿力亚·麦麦提敏张仲瑞艾柯代·艾地汗徐伟龚普阳西南民族大学药学院四川成都610041 枣庄市妇幼保健院中医科山东枣庄277000

桑椹Mori Fructus是使用历史悠久的药食两用中药,有滋阴补血及生津润燥之功效。现代研究表明桑椹主要含有黄酮、酚酸、生物碱、苯丙素、苯并呋喃、萜类及多糖等化学成分。药理学研究证实其主要具有调血脂、抗糖尿病、保肝、抗氧化、抗... 详细信息

桑椹Mori Fructus是使用历史悠久的药食两用中药,有滋阴补血及生津润燥之功效。现代研究表明桑椹主要含有黄酮、酚酸、生物碱、苯丙素、苯并呋喃、萜类及多糖等化学成分。药理学研究证实其主要具有调血脂、抗糖尿病、保肝、抗氧化、抗衰老、神经保护、免疫调节、抗炎、抗肿瘤、骨保护及抗便秘等作用。通过对近年来国内外关于桑椹化学成分和药理作用研究报道进行总结,为桑椹药用价值的深入挖掘和相关产品的开发提供参考。

关键词：桑椹多酚多糖保肝调血脂抗糖尿病抗动脉粥样硬化神经保护

The importance of data assimilation components for initial conditions and subsequent error growth

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Science China Earth Sciences 2024年第1期67卷 105-116页

作者： zhongrui WANG Haohao SUN Lili LEI Zhe-Min TAN Yi zhang Key Laboratory of Mesoscale Severe Weather Ministry of Educationand School of Atmospheric SciencesNanjing UniversityNanjing 210023China Frontiers Science Center for Critical Earth Material Cycling Nanjing UniversityNanjing 210023China

Despite a specific data assimilation method,data assimilation(DA)in general can be decomposed into components of the prior information,observation forward operator that is given by the observation type,observation error covariances,and background error *** a classic Lorenz model,the influences of the DA components on the initial conditions(ICs)and subsequent forecasts are systematically investigated,which could provide a theoretical basis for the design of DA for different scales of *** forecast errors undergo three typical stages:a slow growth stage from 0 h to 5 d,a fast growth stage from 5 d to around 15 d with significantly different error growth rates for ensemble and deterministic forecasts,and a saturation stage after 15 *** strategies that provide more accurate ICs can improve the *** assimilation is superior to offline assimilation,and a flow-dependent background error covariance matrix(Pf)provides better analyses than a static background error covariance matrix(B)for instantaneous observations and frequent time-averaged observations;but the opposite is true for infrequent time-averaged observations,since cycling simulation cannot construct informative priors when the model lacks predictive skills and the flow-dependent Pf cannot effectively extract information from low-informative observations as the static *** observations contain more information than time-averaged observations,thus the former is preferred,especially for infrequent observing ***,ensemble forecasts have advantages over deterministic forecasts,and the advantages are enlarged with less informative observations and lower predictive-skill model priors.

关键词： Data assimilation Atmospheric predictability Background error covariances Ensemble forecasts

Rhizosphere and bulk soil enzyme activities in a Nothotsuga longibracteata forest in the Tianbaoyan National Nature Reserve,Fujian Province,China

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Journal of Forestry Research 2017年第3期28卷 521-528页

作者： Shihong Xiao Huiming You Weibin You Jinshan Liu Changtang Cai Jianqin Wu Zhirong Ji Shihua Zhan Zhesen Hu zhongrui zhang Dongjin He College of Forestry Fujian Agriculture and Forestry UniversityFuzhou 350002People's Republic of China Tianbaoyan National Nature Reserve Yong'an 366032People's Republic of China College of Computer and Information Science Fujian Agriculture and Forestry UniversityFuzhou 350002People's Republic of China College of Geographical Sciences Fujian Normal UniversityFuzhou 350007People's Republic of China

The rhizosphere, distinct from bulk soil, is defined as the volume of soil around living roots and influenced by root activities. We investigated protease, invertase, cellulase, urease, and acid phosphatase activities in rhizosphere and bulk soils of six Nothotsuga longibracteata forest communities within Tianbaoyan National Nature Reserve, including N. longibracteata ＋ either Phyllostachys pubescens, Schima superba, Rhododendron simiarum, Cunninghamia lanceolata, or Cyclobalanopsis glauca, and N. longibracteata pure forest. Rhizosphere soils possessed higher protease, invertase, cellulase, urease, and acid phosphatase activities than bulk soils. The highest invertase, urease, and acid phosphatase activities were observed in rhizosphere samples of N. longibracteata ＋ S. superba. Protease was highest in the N. longibracteata ＋ R. simiarum rhizosphere, while cellulase was highest in the pure N. longibracteata forest rhizosphere. All samples exhibited obvious rhizosphere effects on enzyme activities with a significant linear correlation between acid phosphatase and cellulase activities （p 〈 0.05） in rhizosphere soils and between protease and acid phosphatase activities （p 〈 0.05） in bulk soils. A principal component analysis, correlating 13 soil chemical properties indices relevant to enzyme activities, showed that protease, invertase, acid phosphatase, total N, and cellulase were the most important variables impacting rhizosphere soil quality.

关键词： Bulk soil Enzyme activities Rhizosphere soil Tianbaoyan National Nature Reserve Nothotsuga longibracteata

Relationship between the stoichiometric characteristics and leaf functional traits of Castanopsis hystrix in different ages

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林业与环境科学 2020年第2期36卷 1-6页

作者： zhang zhongrui Qi Ye Ding Xiaogang Yang Haiyan Wei Dan zhang Geng Zhu Hangyong Chen Li Guangdong Provincial Key Laboratory of Silviculture Protection and Utilization/Guangdong Academy of ForestryGuangzhouGuangdong 510520China

Both the stoichiometric characteristics and leaf functional traits can reflect the adaptability of plants to changes in the external living *** particular,for varying aged forest plants,the study of stoichiometric characteristics and leaf functional traits can reflect the plant’s life history strategy and its resource investment and allocation *** this paper,the 1.5-year-old,5-year-old,15-year-old and 20-year-old Castanopsis hystrix were selected as the research objects to investigate the trends of stoichiometry and leaf functional traits,and their synergistic changes were *** results showed that with the increase of age,the stability of *** stoichiometry gradually increased,and the functional traits also tended to invest in ***,there was no synergistic change between the two,which might be attributed to the different sensitivity of the *** leaf to the environment at the life history level of 1.5-year-old to 20-year-old.

关键词： Castanopsis hystrix different age stoichiometry leaf functional traits

Assessment of Forest Soil Fertility in Yunfu City based on Grey Correlation

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林业与环境科学 2019年第6期35卷 16-21页

Due to the spatial heterogeneity of forest soil,it is a difficult problem to evaluate the forest soil fertility on a large *** study conducted a grid survey of forest soil in Yunfu City,Guangdong Province,and used the the gray correlation system to evaluate forest soil fertility in each *** results showed that the effect of using the gray correlation analysis to evaluate soil fertility in Yunfu city was ideal,and the fertilizer strength in each county was in order of Yunan,Yun'an,Yuncheng,Xinxing,and *** results can provide an appropriate scientific basis for forestry division within the county scale.

关键词： grey correlation forest soil fertility Yunfu City

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气候变化对青藏高原河流源区径流的影响

Engineering 2024年第3期34卷 133-142页

作者： Zhenxin Bao Jianyun zhang Yanqing Lian Guoqing Wang Junliang Jin zhongrui Ning Jiapeng zhang Yanli Liu Xiaojun Wang State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Nanjing Hydraulic Research Institute Nanjing 210024China Yangtze Institute for Conservation and Development Hohai UniversityNanjing 210098China College of Hydrology and Water Resources Hohai UniversityNanjing 210098China

The Tibetan Plateau(TP)is the headwater of the Yangtze,Yellow,and the transboundary Yarlung Zangbo,Lancang,and Nujiang Rivers,providing essential and pristine freshwater to around 1.6 billion people in Southeast and South ***,the temperature rise TP has experienced is almost three times that of the global warming *** rising temperature has resulted in glacier retreat,snow cover reduction,permafrost layer thawing,and so *** we show,based on the longest observed streamflow data available for the region so far,that changing climatic conditions in the TP already had significant impacts on the streamflow in the headwater basins in the *** analysis indicated that the annual average temperature in the headwater basins of these five major rivers has been rising on a trend averaging 0.38℃-decade^(-1) since 1998,almost triple the rate before 1998,and the change of streamflow has been predominantly impacted by precipitation in these headwater *** a result,streamflow in the Yangtze,Yarlung Zangbo,Lancang,and Nujiang River headwater areas is on a decreasing trend with a reduction of flow ranging from 3.0-10^(9)-5.9-10^(9) m^(3)·decade^(-1)(-9.12%to-16.89%per decade)since *** increased precipitation in the Tangnahai(TNH)and Lanzhou(LZ)Basins contributed to the increase of their streamflows at 8.04%and 14.29%per decade,*** the increased streamflow in the headwater basins of the Yellow River may ease some of the water resources concerns,the decreasing trend of streamflow in the headwater areas of the southeastern TP region since 1998 could lead to a water crisis in transboundary river basins for billions of people in Southeast and South Asia.

关键词： Tibetan Plateau Streamflow Change trend Climate change

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无人机辅助巡视及绝缘子缺陷图像识别研究

电子测量与仪器学报 2015年第12期29卷 1862-1869页

作者：王淼杜毅张忠瑞国网通用航空有限公司北京100031 国网四川省电力公司检修公司成都610052 国网辽宁省电力有限公司沈阳110006

针对传统的输电线路人工巡视存在安全、管理、效率方面的不足,引入六旋翼无人机,利用其良好的机动性、操控性和图像识别技术对输电线路进行辅助巡视。论文分析无人机辅助巡视的系统结构、作业模式及搭载设备,针对拍摄的高清细节巡视图像... 详细信息

针对传统的输电线路人工巡视存在安全、管理、效率方面的不足,引入六旋翼无人机,利用其良好的机动性、操控性和图像识别技术对输电线路进行辅助巡视。论文分析无人机辅助巡视的系统结构、作业模式及搭载设备,针对拍摄的高清细节巡视图像,在采用阈值分割,形态学和边缘检测技术的基础上,设计绝缘子的连通域特征和形状特征,提出能适应航拍的复杂背景和多角度的绝缘子自爆缺陷识别算法,实现绝缘子缺陷的自动侦测,减少人工干预。测试表明,无人机辅助巡视系统有效弥补人工巡视的不足,图像识别技术为缺陷判别提供了智能化的决策依据,与传统基于颜色特征算法相比,在复杂背景下识别准确率达到85%,是高新技术在智能电网中应用的有益探索。

关键词：六旋翼无人机输电线路巡视图像识别智能电网

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加入WTO与我国法律制度的改革创新

生产力研究 2000年第6期 57-58页

作者：张中瑞刘巧红山西行政学院省直分院山西太原030024

中国加入WTO不仅是中国经济融入全球市场经济海洋的入海口，也是中国法律制度向国际化、现代化跨越的良机，因此，依照WTO规则及我国的具体承诺，由我国立法机关全面系统地进行“入世修法”已成一项重大历史任务且迫在眉睫。应持既积极... 详细信息

中国加入WTO不仅是中国经济融入全球市场经济海洋的入海口，也是中国法律制度向国际化、现代化跨越的良机，因此，依照WTO规则及我国的具体承诺，由我国立法机关全面系统地进行“入世修法”已成一项重大历史任务且迫在眉睫。应持既积极又慎重的方针对我国现行法律体系进行大刀阔斧的立、改、废，实现我国国内法与世贸组织法的成功对接。这是维护我国利益和减少入世法律风险的上策。

关键词： WTO 中国法律制度法律创新