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Crop pest image recognition based on the improved ViT method Author links open overlay panel

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Information Processing in Agriculture 2024年第2期11卷 249-259页

作者： Xueqian Fu Qiaoyu Ma Feifei Yang chunyu zhang Xiaolong Zhao Fuhao Chang Lingling Han College of Information and Electrical Engineering China Agricultural UniversityBeijingChina National Innovation Center for Digital Fishery China Agricultural UniversityBeijingChina Key Laboratory of Smart Farming Technologies for Aquatic Animal and Livestock Ministry of Agriculture and Rural AffairsBeijingChina Beijing Engineering and Technology Research Center for Internet of Things in Agriculture BeijingChina

The crop pests and diseases in agriculture is one of the most important reason for the reduction of bulk grain and oil crops and the decline of fruit and vegetable crop quality,which threaten macroeconomic stability and sustainable ***,the recognition method based on manual and instruments has been unable to meet the needs of scientific research and production due to its strong subjectivity and low *** recognition method based on pattern recognition and deep learning can automatically fit image features,and use features to classify and predict *** study introduced the improved Vision Transformer(ViT)method for crop pest image *** them,the region with the most obvious features can be effectively selected by block *** self-attention mechanism of the transformer can better excavate the special solution that is not an obvious lesion *** the experiment,data with 7 classes of examples are used for *** can be illustrated from results that this method has high accuracy and can give full play to the advantages of image processing and recognition technology,accurately judge the crop diseases and pests category,provide method reference for agricultural diseases and pests identification research,and further optimize the crop diseases and pests control work for agricultural workers in need.

关键词： Crop diseases recognition Fruit tree leaf disease Vision Transformer Deep learning Computer Vision

Development of a rapid and efficient system for CR genes identification based on hairy root transformation in Brassicaceae

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Horticultural Plant Journal 2024年第4期10卷 1049-1060页

作者： Wenlin Yu Lu Yang Yuanyuan Xiang Rongde Li Xueqing Zhou Longcai Gan Xianyu Xiang Yunyun zhang Lei Yuan Yanqing Luo Genze Li Youning Wang Yinhua Chen Peng Chen chunyu zhang National Key Laboratory of Crop Genetic Improvement and College of Plant Science and Technology Huazhong Agricultural UniversityWuhanHubei 430070China National Key Laboratory for Tropical Crop Breeding Sanya Nanfan Research InstituteHainan UniversitySanyaHainan 572025China National Agro-Tech Extension and Service Center Beijing 100125China Industrial Crops Research Institute Yunnan Academy of Agricultural SciencesKunmingYunnan 650221China College ofAgronomy NorthwestA&F UniversityYanglingShaanxi712100China

Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae *** of clubroot resistant cultivars based on mapping and cloning of resistant genes is commonly regarded as the most cost-effective and efficient way to fight against this *** traditional way of R gene functional validation requires stable transformation that is both time-and *** this study,a rapid and efficient hairy-root transgenic protocol mediated by Agrobacterium rhizogenes was *** transformation positive rate was over 80%in Brassica napus showed by GUS reporter gene and this transformation only took 1/6 of the time compared with stable *** system was applicable to different *** varieties and other cruciferous crops including Brassica rapa and Brassica *** particular,two known CR genes,CRA3.7.1 and CRA8.2.4 were used respectively,as example to show that the system works well for CR gene study combined with subsequent *** infection in *** importantly,it works both in over-expression that led to disease resistance,as well as in RNAi which led to disease susceptible ***,this system can be used in batch-wise identification of CR genes,and also offered the possibility of manipulating key genes within the *** genome that could improve our knowledge on host-pathogen interaction.

关键词： Brassicaceae Agrobacterium rhizogenes Hairy root transformation Clubroot Gene function

高地应力条件下隧道多力学特性锚杆模型及应用研究

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隧道建设（中英文） 2024年第3期44卷 506-514页

作者：张春瑜中铁十八局集团有限公司天津300222

为解决FLAC3D中Cable模型无法模拟锚杆(索)断裂失效,因而难以合理分析复杂地质条件下围岩稳定性的问题,采用数值计算手段对锚杆模型进行改进,提出锚杆(索)的失效判据,基于FISH语言修正Cable模型法向及锚固剂轴向本构关系,并将算法嵌入... 详细信息

为解决FLAC3D中Cable模型无法模拟锚杆(索)断裂失效,因而难以合理分析复杂地质条件下围岩稳定性的问题,采用数值计算手段对锚杆模型进行改进,提出锚杆(索)的失效判据,基于FISH语言修正Cable模型法向及锚固剂轴向本构关系,并将算法嵌入到运行程序中。结合Link模型构建多力学特性锚杆模型(MMC模型),并通过开展锚杆拉拔及模拟试验,对MMC模型进行验证。以月直山隧道工程为背景,构建隧道支护算例,对比Cable模型及MMC模型在工程模拟分析中的应用效果。结果表明:1)修正后的锚杆及锚固剂轴向本构模型包含破坏失效阶段,符合锚杆实际力学行为;2)锚杆拉拔试验模拟结果和真实试验结果接近,最大误差为2.9%,说明MMC模型能够合理模拟真实锚杆的受力及失效破坏特征;3)MMC模型在工程模拟中能直观地展现破断失效位置,且能够模拟锚固系统失效,而Cable模型在锚杆达到破坏条件后仍持续为围岩提供支护力,计算结果与实际存在较大偏差;4)MMC模型扩大了FLAC3D的应用范围及适用性,提高了锚杆支护的模拟能力。

关键词：隧道高地应力锚杆多力学特性锚杆模型 Cable模型锚杆失效判据

Dt1 inhibits SWEET-mediated sucrose transport to regulate photoperiod-dependent seed weight in soybean

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Molecular Plant 2024年第3期17卷 496-508页

作者： Xiaoming Li Zhonghui Chen Haiyang Li Lin Yue Cuirong Tan Hongjie Liu Yilong Hu Yuhua Yang Xiani Yao Lingping Kong Xiang Huangi Bin Yu chunyu zhang Yuefeng Guan Baohui Liu Fanjiang Kong Xingliang Hou Guangdong Provincial Key Laboratory of Applied Botany&State Key Laboratory of Plant Diversity and Specialty Crops South China Botanical GardenChinese Academyof SciencesGuangzhou510650China Guangdong Provincial Key Laboratory of Plant Adaptation and Molecular Design Guangzhou Key Laboratory of Crop Gene EditingInnovative Center of Molecular Genetics and EvolutionSchool of Life SciencesGuangzhou UniversityGuangzhou 510006China University of Chinese Academy of Sciences Beijing 100049China College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193China

Soybean is a photoperiod-sensitive short-day crop whose reproductive period and yield are markedly affected by day-length *** weight is one of the key traits determining the soybean yield;how-ever,the prominent genes that control the final seed weight of soybean and the mechanisms underlying the photoperiod's effect on this trait remain poorly *** this study,we identify SwW19 as a major locus controlling soybean seed weight by QTL mapping and determine Dt1,an orthologous gene of Arabidopsis TFL1 that is known to govern the soybean growth habit,as the causal gene of the SW19 *** showed that Dt1 is highly expressed in developing seeds and regulates photoperiod-dependent seed weight in *** analyses revealed that the Dt1 protein physically interacts with the sucrose transporter GmSWEET10a to negatively regulate the import of sucrose from seed coat to the embryo,thus modulating seed weight under long ***,Dt1 does not function in seed development under short days due to its very low ***,we discovered a novel natural allelic variant of Dt1(H4 haplotype)that decouples its pleiotropic effects on seed size and growth habit;i.e.,this variant remains functional in seed development but fails to regulate the stem growth habit of ***,our findings provide new insights into how soybean seed development responds to photoperiod at different latitudes,offering an ideal genetic component for improving soybean's yield by manipulating its seed weightandgrowth habit.

关键词： soybean seed weight photoperiod dt1 sucrose transport

东北天然次生针阔混交林乔木层碳储量变化的采伐干扰响应

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林业科学 2024年第7期60卷 17-27页

作者：杨润露王娟张春雨北京林业大学林木资源高效生产全国重点实验室北京100083

[目的]探究采伐干扰对东北典型天然次生针阔混交林乔木层碳储量变化的影响,为东北地区森林可持续经营提供理论依据。[方法]在吉林省林业实验区国有林保护中心选取4块1 hm^(2)针阔混交林样地,2011年开展初次调查,同年冬季进行采伐作业,2... 详细信息

[目的]探究采伐干扰对东北典型天然次生针阔混交林乔木层碳储量变化的影响,为东北地区森林可持续经营提供理论依据。[方法]在吉林省林业实验区国有林保护中心选取4块1 hm^(2)针阔混交林样地,2011年开展初次调查,同年冬季进行采伐作业,2013、2015、2018和2021年复测保留木。采用双变量线性回归法,探讨采伐强度、物种多样性、功能多样性、系统发育多样性和群落加权平均性状值对碳储量和碳增量的影响;使用多元线性回归模型,比较各变量的贡献程度;利用结构方程模型,检验各变量对碳储量和碳增量的直接和间接效应。[结果]1)碳储量和碳增量多元线性回归模型中,采伐强度对碳储量和碳增量的贡献分别占总解释量的25%和5%;植物物种多样性对碳储量和碳增量的贡献分别占总解释量(物种、功能、系统发育多样性)的67%和58%;群落加权平均性状值对碳储量和碳增量的贡献分别占总解释量的8%和37%。2)碳储量结构方程模型中,采伐强度对系统发育多样性、功能多样性、最大树高加权性状值和碳储量具有显著负向效应,路径系数分别为−0.221、−0.454、−0.337和−0.229;采伐强度对木质密度加权性状值具有显著正向效应,路径系数为0.368;采伐强度对物种多样性的直接效应不显著;物种多样性和功能多样性对碳储量具有显著正向效应,路径系数分别为0.306和0.235;系统发育多样性和群落加权平均值对碳储量的直接效应不显著。3)碳增量结构方程模型中,最大树高加权性状值对碳增量具有显著正向效应,功能多样性与木质密度加权性状值不相关,其他变量间的关系与碳储量模型相同。[结论]物种多样性、功能多样性、群落加权平均性状值对碳储量和碳增量具有直接影响,森林经营时可通过增加植物种类以促成功能多样的林分来提高森林碳汇能力。采伐强度直接或间接通过功能多样性和群落加权平均性状值减少碳储量和碳增量,在森林经营中应合理采伐,以提高森林碳汇能力。

关键词：采伐干扰植物物种多样性群落加权平均性状值碳储量碳增量

基于FPGA的新能源低压直流配电系统暂态实时仿真研究

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电工技术学报 2024年第17期39卷 5365-5378,5393页

作者：王守相张春雨赵倩宇天津大学教育部智能电网重点实验室天津300072 天津市电力系统仿真控制重点实验室天津300072

对新能源低压直流配电系统开展暂态实时仿真研究对优化其运行控制具有重要作用。由于现场可编程门阵列(FPGA)内部集成了大量具有不同功能的电路,FPGA正成为电力系统暂态实时仿真领域主要的计算载体之一。该文面向新能源低压直流配电系... 详细信息

对新能源低压直流配电系统开展暂态实时仿真研究对优化其运行控制具有重要作用。由于现场可编程门阵列(FPGA)内部集成了大量具有不同功能的电路,FPGA正成为电力系统暂态实时仿真领域主要的计算载体之一。该文面向新能源低压直流配电系统的暂态实时仿真需求,开发了一种基于FPGA的包含小型分布式风力发电、光伏发电以及蓄电池储能单元的新能源低压直流配电系统暂态实时仿真器。首先,研究构建了分布式发电单元和典型控制回路的计算模块,利用FPGA的并行计算特性并结合“算法-结构-有效匹配(AAA)”理念建立了底层模块串并联混合求解结构;然后,在节点分析法的框架下,建立了一种结合矩阵LDU分解和有向无环图(DAG)的电气系统节点电导矩阵并行求解方法;最后,在建立电气系统与控制系统并行求解架构的基础上,开发了一种基于FPGA的新能源低压直流配电系统暂态实时仿真器,通过将其仿真结果与PSCAD/EMTDC离线仿真平台的计算结果进行对比,验证了所开发暂态实时仿真器的有效性和准确性。

关键词：现场可编程门阵列(FPGA) 实时仿真分布式发电低压直流配电系统并行计算

长白山不同演替阶段温带森林木本植物菌根类型对林下草本植物多样性的影响

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生物多样性 2024年第1期32卷 16-27页

作者：殷正张乃莉张春雨赵秀海北京林业大学国家林业和草原局森林经营工程技术研究中心北京100083 北京林业大学林木资源高效生产全国重点实验室北京100083 北京林业大学林学院森林培育与保护教育部重点实验室北京100083 国家林业和草原局黑龙江三江平原沼泽草甸生态系统定位观测研究站黑龙江双鸭山518000

温带森林生态系统草本植物多样性丰富,是植物多样性的重要组分,对森林生态系统功能的调控同样具有重要作用,但却未受到广泛关注。本研究依托长白山地区原始阔叶红松(Pinus koraiensis)林和采伐干扰后形成的次生针阔混交林中共128个1 m×... 详细信息

温带森林生态系统草本植物多样性丰富,是植物多样性的重要组分,对森林生态系统功能的调控同样具有重要作用,但却未受到广泛关注。本研究依托长白山地区原始阔叶红松(Pinus koraiensis)林和采伐干扰后形成的次生针阔混交林中共128个1 m×1 m草本植物样方连续两年的调查数据,深入解析了两类森林林下丛枝菌根(arbuscular mycorrhizal, AM)草本植物和非菌根(non-mycorrhizal, NM)草本植物多样性的异同;并运用广义线性混合效应模型分析了AM木本植物和外生菌根(ectomycorrhizal,EcM)木本植物以及环境因子对林下草本植物多样性的影响。结果表明:原始阔叶红松林中群落水平上草本植物和AM草本植物的多度和多样性均显著高于受人类采伐干扰后形成的次生针阔混交林,而NM草本植物无显著差异。林下草本植物多度和多样性受到木本植物邻体的显著影响,但其作用强度受到环境因素的调控。在次生针阔混交林中,群落水平上的草本植物多样性主要受木本植物邻体多样性和林下叶面积指数的直接影响。AM草本植物多度与EcM木本植物邻体密度显著负相关,且这种负作用关系随着土壤含水量的增加而减弱。在阔叶红松林中,土壤含水量直接影响群落水平草本植物和AM草本植物的多度,且土壤含水量的高低调控木本植物邻体对群落水平草本多度和多样性的影响。综上所述,采伐干扰显著降低了温带森林生态系统中草本植物多度和多样性,而上层木本植物邻体的菌根类型和环境因子对林下草本植物群落构建表现出明显的交互作用。

关键词：草本植物演替阶段菌根真菌物种多样性

花岗岩矿物正交偏光镜下图像人工智能识别研究

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矿物学报 2024年第1期44卷 11-23页

作者：王名越狄永军张春禹中国地质大学(北京)地球科学与资源学院北京100083

人工智能在地球科学领域中的应用是近年来研究的热点,对地球科学的发展有着重要意义,其应用之一就是使用计算机视觉技术实现岩石或矿物的自动化识别分类。然而,目前大多研究直接对岩石薄片图像进行分类,不能够精细定位并识别薄片中多且... 详细信息

人工智能在地球科学领域中的应用是近年来研究的热点,对地球科学的发展有着重要意义,其应用之一就是使用计算机视觉技术实现岩石或矿物的自动化识别分类。然而,目前大多研究直接对岩石薄片图像进行分类,不能够精细定位并识别薄片中多且复杂的矿物目标。虽然现已有许多学者将目标检测技术应用于岩石矿物的图像识别分类中,但这些方法识别的对象大多是岩石手标本图像,只能对图像中的单一对象检测。在识别分类研究领域中,缺少对岩石薄片镜下图像识别的算法及质量较好的相关数据集。为了解决这些问题,本文首先采集了3000张正交偏光镜下花岗岩薄片图像,标注矿物样本10000余个,并通过数据增广方式对数据集进行增强,建立了一个质量较好、具有多样性的数据集。其次本文提出基于Yolov5x的改进算法RDB-Yolov5x。这种方法在特征提取过程中添加了密集连接方式,使用密集连接残差模块(RDB)替代传统的残差结构,有效地保留了图像的语义和位置信息细节。实验结果表明该方法泛化能力较好,在对图像中小尺寸、特征模糊的矿物颗粒的识别中表现出优秀的性能,可以准确有效地对花岗岩中的五类目标矿物(石英、黑云母、白云母、斜长石、钾长石)进行识别,平均精度均值m AP达到94.1%。较对比方法,在IoU阈值为50%时提高了0.5%,阈值为95%时提高了1%。

关键词：人工智能识别岩石矿物 RDB-Yolov5x 镜下图像

Functional genomics of Brassica napus:Progresses,challenges,and perspectives

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Journal of Integrative Plant Biology 2024年第3期66卷 484-509页

作者： Zengdong Tan Xu Han Cheng Dai Shaoping Lu Hanzi He Xuan Yao Peng Chen Chao Yang Lun Zhao Qing-Yong Yang Jun Zou Jing Wen Dengfeng Hong Chao Liu Xianhong Ge Chuchuan Fan Bing Yi chunyu zhang Chaozhi Ma Kede Liu Jinxiong Shen Jinxing Tu Guangsheng Yang Tingdong Fu Liang Guo Hu Zhao National Key Laboratory of Crop Genetic Improvement Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhan 430070China Yazhouwan National Laboratory Sanya 572025China

Brassica napus,commonly known as rapeseed or canola,is a major oil crop contributing over 13%to the stable supply of edible vegetable oil *** and understanding the gene functions in the *** genome is crucial for genomic breeding.A group of genes controlling agronomic traits have been successfully cloned through functional genomics studies in *** this review,we present an overview of the progress made in the functional genomics of ***,including the availability of germplasm resources,omics databases and cloned functional *** on the current progress,we also highlight the main challenges and perspectives in this *** advances in the functional genomics of *** contribute to a better understanding of the genetic basis underlying the complex agronomic traits in *** and will expedite the breeding of high quality,high resistance and high yield in *** varieties.

关键词： accelerate breeding Brassica napus functional genomics high resistance high yield