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New method for cotton fractional vegetation cover extraction based on UAV RGB images

International Journal of Agricultural and Biological Engineering 2022年第4期15卷 172-180页

作者： huanbo yang Yubin Lan Liqun Lu Daocai Gong Jianchi Miao Jing Zhao School of Agricultural and Food Engineering Shandong University of TechnologyZibo 255000ShandongChina International Precision Agriculture Aviation Application Technology Research Center Shandong University of TechnologyZibo 255000ShandongChina School of Transportation and Vehicle Engineering Shandong University of TechnologyZibo 255000ShandongChina

As the key principle of precision farming,the distribution of fractional vegetation cover is the basis of crop management within the field *** estimate crop FVC rapidly at the farm scale,high temporal-spatial resolution imagery obtained by unmanned aerial vehicle(UAV)was *** verify the application potential of consumer-grade UAV RGB imagery in estimated FVC,blue-green characteristic vegetation index(TBVI)and red-green vegetation index(TRVI)were proposed in this study according to the differences of the gray value among cotton vegetation,soil and shadow in the ***,two new constructed indices and several published indices were used to extract visible light images and generate greyscale images for each of the visible light vegetation ***,the thresholds of cotton vegetation and non-vegetation pixels were established based on the vegetation index threshold method which combines support vector machine classification and vegetation ***,the accuracy difference in vegetation information extraction between the newly constructed and several published indices was *** results show that the accuracy of the information extracted by TRVI is higher than that of subdivision index of other visible light(FVC extraction precision in the first bud stage of cotton:R2=0.832,RMSE=2.307,nRMSE=4.405%;FVC extraction precision in the bud stage of cotton:R2=0.981,RMSE=1.393,nRMSE=1.984%;FVC extraction precision in the flowering stage of cotton:R2=0.893,RMSE=2.101,nRMSE=2.422%;FVC extraction precision in the boll stage of cotton:R2=0.958,RMSE=1.850,nRMSE=2.050%).

关键词： cotton UAV visible light images fractional vegetation cover vegetation index threshold method TRVI TBVI

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Exploring the potential of extrachromosomal DNA as a novel oncogenic driver

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Science China Life Sciences 2025年第1期 144-157页

作者： huanbo Zhu Longtao Huangfu Junbing Chen Jiafu Ji Xiaofang Xing Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing) Division of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital & Institute Department of Gastrointestinal Cancer Center Peking University Cancer Hospital & Institute Department of Liver Surgery & Transplantation Liver Cancer InstituteZhongshan HospitalFudan University Key Laboratory of Carcinogenesis and Cancer Invasion Ministry of Education State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers Beijing Key Laboratory of Carcinogenesis and Translational ResearchDivision of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital & Institute

Extrachromosomal DNA(ecDNA) is a form of circular DNA mostly found in tumor cells. Unlike the typical chromosomal DNA, ecDNA is circular, self-replicating, and carries complete or partial gene fragments. Although ecDNA occurrence remains a rare event in cancer, recent studies have shown that oncogene amplification on ecDNA is widespread throughout many types of cancer, implying that ecDNA plays a central role in accelerating tumor evolution. ecDNA has also been associated with increased tumor mutation burden, chromosomal instability, and even tumor microenvironment remodeling. ecDNA may be crucial in influencing tumor heterogeneity, drug sensitivity,oncogenic senescence, and tumor immunogenicity, leading to a worsening prognosis for tumor patients. In this way, several clinical trials have been conducted to investigate the importance of ecDNA in clinical treatment. In this review, we summarize the biogenesis, characteristics, and current research methods of ecDNA, discuss the vital role of ecDNA-caused tumor heterogeneity in cancers, and highlight the potential role of ecDNA in cancer therapy.

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基于无人机可见光图像的夏季玉米植被覆盖度提取方法

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农业机械学报 2019年第5期50卷 232-240页

作者：赵静杨焕波兰玉彬鲁力群贾鹏李志铭山东理工大学农业工程与食品科学学院淄博255049 山东理工大学国际精准农业航空应用技术研究中心淄博255049 山东理工大学交通与车辆工程学院淄博255049

为准确快速获取夏季玉米四叶期、拔节期、抽穗期和花粒期的植被覆盖度信息,利用无人机获取玉米田间可见光图像,对图像可见光波段提取的多种植被指数进行分析和比较,选择差异植被指数(Visible-band difference vegetation index,VDVI)、... 详细信息

为准确快速获取夏季玉米四叶期、拔节期、抽穗期和花粒期的植被覆盖度信息,利用无人机获取玉米田间可见光图像,对图像可见光波段提取的多种植被指数进行分析和比较,选择差异植被指数(Visible-band difference vegetation index,VDVI)、过绿指数(Excess green,EXG)和归一化绿蓝差异指数(Normalized green-blue difference index,NGBDI),结合监督分类提取了玉米4个时期的植被覆盖度信息。通过对试验田4个阶段的单幅图像监督分类处理,将其目标物分为土壤和玉米植被两类;分别统计监督分类后图像中土壤和玉米的VDVI像元直方图,将两者的像元直方图交点作为植被覆盖度提取阈值,同理获得EXG和NGBDI对应的玉米植被覆盖度提取阈值;利用获取的玉米植被3种覆盖度提取阈值,对玉米4个时期的植被覆盖度进行提取,并对提取精度进行了验证。结果表明,VDVI对应4个生长时期的植被覆盖度提取误差分别为1. 21%、4. 88%、2. 31%和3. 61%; EXG对应的植被覆盖度提取误差分别为1. 38%、1. 25%、0. 89%和0. 33%; NGBDI提取误差为1. 61%、3. 31%、1. 99%和3. 25%,EXG在夏季玉米4个生长时期的植被覆盖度提取效果最好。将玉米4个生长时期单幅图像确定的阈值作为固定阈值,对剔除确定阈值的单幅图像的试验田全景图像进行植被覆盖度提取,并对提取效果进行验证。结果表明,采用监督分类与可见光植被指数统计直方图相结合确定阈值的方法提取玉米植被覆盖度效果较好。

关键词：夏季玉米无人机可见光图像植被覆盖度植被指数阈值提取

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基于无人机可见光图像的作物分类研究

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西北农林科技大学学报（自然科学版） 2020年第6期48卷 137-144,154页

作者：李志铭赵静兰玉彬崔欣杨焕波山东理工大学农业工程与食品科学学院山东淄博255000 国家精准农业航空施药技术国际联合研究中心山东理工大学分中心山东淄博255000

【目的】采用无人机遥感技术对作物进行分类识别,为及时获取农田信息、制定农田管理策略及产量估测提供技术支持。【方法】采用无人机遥感平台,获取试验区域玉米、桃树、菜花、大豆的可见光正射影像;利用HSV色彩空间转换和纹理滤波,获... 详细信息

【目的】采用无人机遥感技术对作物进行分类识别,为及时获取农田信息、制定农田管理策略及产量估测提供技术支持。【方法】采用无人机遥感平台,获取试验区域玉米、桃树、菜花、大豆的可见光正射影像;利用HSV色彩空间转换和纹理滤波,获取不同地物的24项纹理特征与3项色彩特征。分别通过ReliefF算法及基于支持向量机的递归特征消除算法(support vector machine-recursive feature elimination,SVM-RFE)进行特征选择与分类,建立6种监督分类模型,利用得到的特征子集对其进行训练,对各模型分类效果进行精度评价。【结果】由SVM-RFE特征子集训练的6种监督分类模型测试集的分类精度均高于80%,分类精度平均提高5.023%,优于ReliefF特征子集训练的监督分类模型,其中SVM-RFE特征子集与支持向量机模型组合对作物的监督分类效果最佳,总体精度达83.417%,Kappa系数为78.60。【结论】基于无人机遥感技术的作物分类识别是可行的。

关键词：作物分类识别无人机遥感可见光图像特征选择监督分类

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基于无人机多光谱遥感图像的玉米田间杂草识别

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中国农业科学 2020年第8期53卷 1545-1555页

作者：赵静李志铭鲁力群贾鹏杨焕波兰玉彬山东理工大学农业工程与食品科学学院山东理工大学国际精准农业航空应用技术研究中心山东理工大学交通与车辆工程学院

【目的】为了精确高效识别玉米田间杂草,减少除草剂施用,提高玉米种植管理精准性。【方法】通过六旋翼无人机搭载多光谱相机获取玉米田块多光谱图像。为分离图像中植被与非植被像元,计算了7种植被指数,采用最大类间方差法提取植被指数... 详细信息

【目的】为了精确高效识别玉米田间杂草,减少除草剂施用,提高玉米种植管理精准性。【方法】通过六旋翼无人机搭载多光谱相机获取玉米田块多光谱图像。为分离图像中植被与非植被像元,计算了7种植被指数,采用最大类间方差法提取植被指数图像中非植被区域,制作掩膜文件并对多光谱图像掩膜。通过主成分分析对多光谱图像进行变换,保留信息量最多的前3个主成分波段。将试验区域分为训练区域和验证区域,在训练区域中分别选取了675处玉米和525处杂草样本对监督分类模型进行训练,在验证区域选取了240处玉米样本及160处杂草样本评价模型分类精度。将7种植被指数、3个主成分波段的24个纹理特征及经过滤波的10个反射率,共计41项特征作为样本特征参数。利用支持向量机-特征递归消除算法(support vector machines-feature recursive elimination,SVM-RFE)和Relief算法从41项特征中各筛选14项特征构成特征子集,采用支持向量机、K-最近邻、Cart决策树、随机森林和人工神经网络对特征子集进行监督分类。【结果】支持向量机与随机森林对全部特征及2个特征子集分类效果较好,支持向量机总体精度为89.13%—91.94%,Kappa>0.79,随机森林总体精度为89.27%—90.95%,Kappa>0.79。【结论】SVM-RFE算法对数据降维效果优于Relief算法,支持向量机(SVM)模型对区域冠层尺度下玉米与杂草的分类效果最好。

关键词：杂草识别无人机遥感多光谱图像特征选择监督分类

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基于像元二分法的冬小麦植被覆盖度提取模型

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华南农业大学学报 2020年第3期41卷 126-132页

作者：孟沌超赵静兰玉彬鲁力群杨焕波李志铭闫春雨山东理工大学农业工程与食品科学学院山东淄博255000 山东理工大学国际精准农业航空应用技术研究中心山东淄博255000 华南农业大学电子工程学院广东广州510642 山东理工大学交通与车辆工程学院山东淄博255000

【目的】快速准确提取冬小麦返青期植被覆盖度信息。【方法】利用无人机获取田间冬小麦可见光图像,提取图像中4种常见可见光植被指数;在像元二分法原理的基础上,分别构建基于差异植被指数(Visible-band difference vegetation index,VD... 详细信息

【目的】快速准确提取冬小麦返青期植被覆盖度信息。【方法】利用无人机获取田间冬小麦可见光图像,提取图像中4种常见可见光植被指数;在像元二分法原理的基础上,分别构建基于差异植被指数(Visible-band difference vegetation index,VDVI)、过绿指数(Excess green,EXG)、归一化绿蓝差异指数(Normalized green-blue difference index,NGBDI)和归一化绿红差异指数(Normalized green-red difference index,NGRDI)的植被覆盖度提取模型,采用支持向量机(Support vector machine,SVM)监督分类结果作为真值对各模型进行精度验证。【结果】4种模型中,利用VDVI植被覆盖度提取模型获取的植被覆盖度精度最高,提取效果较好。与监督分类结果对比,4种植被覆盖度提取模型的提取误差(EF)分别为3.36%、15.68%、8.74%和15.46%,R2分别为0.9461、0.9344、0.6953和0.7460,均方根误差(RMSE)分别为0.0219、0.0595、0.0420和0.0559。【结论】采用可见光植被指数结合像元二分法构建植被覆盖度提取模型实现了冬小麦返青期植被覆盖度准确快速提取,为植被覆盖度提取提供了一种新途径,可为无人机遥感监测提供参考。

关键词：无人机遥感冬小麦像元二分法可见光植被指数植被覆盖度

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Enriching the Transfer Learning with Pre-Trained Lexicon Embedding for Low-Resource Neural Machine Translation

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Tsinghua Science and Technology 2022年第1期27卷 150-163页

作者： Mieradilijiang Maimaiti yang Liu huanbo Luan Maosong Sun the Institute for Artificial Intelligence Beijing National Research Center for Information Science and TechnologyDepartment of Computer Science and TechnologyTsinghua UniversityBeijing 100084China the Beijing Academy of Artificial Intelligence Beijing Advanced Innovation Center for Language ResourcesBeijing 100084China

Most State-Of-The-Art(SOTA) Neural Machine Translation(NMT) systems today achieve outstanding results based only on large parallel *** large-scale parallel corpora for high-resource languages is easily ***,the translation quality of NMT for morphologically rich languages is still unsatisfactory,mainly because of the data sparsity problem encountered in Low-Resource Languages(LRLs).In the low-resource NMT paradigm,Transfer Learning(TL) has been developed into one of the most efficient *** is difficult to train the model on high-resource languages to include the information in both parent and child models,as well as the initially trained model that only contains the lexicon features and word embeddings of the parent model instead of the child languages *** this work,we aim to address this issue by proposing the language-independent Hybrid Transfer Learning(HTL) method for LRLs by sharing lexicon embedding between parent and child languages without leveraging back translation or manually injecting ***,we train the High-Resource Languages(HRLs) as the parent model with its ***,we combine the parent and child language pairs using the oversampling method to train the hybrid model initialized by the previously parent ***,we fine-tune the morphologically rich child model using a hybrid ***,we explore some exciting discoveries on the original TL *** results show that our model consistently outperforms five SOTA methods in two languages Azerbaijani(Az) and Uzbek(Uz).Meanwhile,our approach is practical and significantly better,achieving improvements of up to 4:94 and 4:84 BLEU points for low-resource child languages Az ! Zh and Uz ! Zh,respectively.

关键词： artificial intelligence natural language processing neural network machine translation low-resource languages transfer learning

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基于无人机可见光遥感和阈值法的玉米植被覆盖度提取

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福建农林大学学报（自然科学版） 2020年第2期49卷 283-288页

作者：杨焕波赵静兰玉彬鲁力群贾鹏李志铭山东理工大学农业工程与食品科学学院山东理工大学国际精准农业航空应用技术研究中心山东理工大学交通与车辆工程学院山东淄博255000

为了快速获取夏季玉米四叶期、拔节期和抽穗期的植被覆盖度信息,以无人机拍摄的夏季玉米3个时期的可见光图像为研究对象,通过计算获取可见光波段的差异植被指数、过绿指数和归一化绿蓝差异指数.利用上述3种植被指数,通过时序交点阈值法... 详细信息

为了快速获取夏季玉米四叶期、拔节期和抽穗期的植被覆盖度信息,以无人机拍摄的夏季玉米3个时期的可见光图像为研究对象,通过计算获取可见光波段的差异植被指数、过绿指数和归一化绿蓝差异指数.利用上述3种植被指数,通过时序交点阈值法和最大熵阈值法提取玉米3个生长时期的植被覆盖度信息,将监督分类结果作为真值对上述两种方法的提取效果进行评价.结果表明,与时序交点阈值法相比,利用最大熵阈值法确定的阈值提取玉米植被覆盖度精度较高,玉米3个生长时期的可见光波段差异(VDVI)植被指数的提取误差分别为4.66%、3.42%和5.81%.

关键词：玉米植被覆盖度最大熵阈值法时序交点阈值法可见光波段植被指数

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Increase in the variability of terrestrial carbon uptake in response to enhanced future ENSO modulation

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 32-38页

作者： Younong Li Li Dan Jing Peng Qidong yang Fuqiang yang Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Key Laboratory of Atmospheric Environment and Processes in the Boundary Layer over the Low-Latitude Plateau Region Department of Atmospheric ScienceYunnan UniversityKunmingChina

El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air *** the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further *** investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 *** results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the *** higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in *** flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through *** occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures.

关键词： Carbon variability ENSO modulation CMIP6 models

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High-temperature-tolerant flexible supercapacitors: Gel polymer electrolytes and electrode materials

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Journal of Energy Chemistry 2025年第1期100卷 426-457页

作者： Chong Peng Xinyi Huang Mingwei Zhao Shuling Liao Quanhong yang Nianjun yang Siyu Yu School of Chemistry & Chemical Engineering Southwest University Nanoyang Group Tianjin Key Laboratory of Advanced Carbon and Electrochemical Energy Storage School of Chemical Engineering and Technology and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin University Department of Chemistry & IMO-IMOMEC Hasselt University

The development of flexible supercapacitors(FSCs) capable of operating at high temperatures is crucial for expanding the application areas and operating conditions of supercapacitors. Gel polymer electrolytes and electrode materials stand as two key components that significantly impact the efficacy of hightemperature-tolerant FSCs(HT-FSCs). They should not only exhibit high electrochemical performance and excellent flexibility, but also withstand intense thermal stress. Considerable efforts have been devoted to enhancing their thermal stability while maintaining high electrochemical and mechanical performance. In this review, the fundamentals of HT-FSCs are outlined. A comprehensive overview of state-of-the-art progress and achievements in HT-FSCs, with a focus on thermally stable gel polymer electrolytes and electrode materials is provided. Finally, challenges and future perspectives regarding HT-FSCs are discussed, alongside strategies for elevating operational temperatures and *** review offers both theoretical foundations and practical guidelines for designing and manufacturing HT-FSCs, further promoting their widespread adoption across diverse fields.

关键词： Flexible supercapacitors High-temperature tolerance Gel polymer electrolytes Electrode materials

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