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融合余弦退火与空洞卷积的遥感影像语义分割

遥感学报 2023年第11期27卷 2579-2592页

作者：唐振超韦蔚罗蔚然胡洁张东映华中科技大学土木与水利工程学院武汉430074 黄河勘测规划设计研究院有限公司郑州450003 郑州大学水利科学与工程学院郑州450001

为了捕捉遥感影像中丰富的上下文信息与多尺度的地物信息,改进集成模型的策略,提高语义分割精度,提出一种融合周期递增余弦退火与多尺度空洞卷积的高分辨率遥感影像语义分割方法。方法引入多尺度并行的空洞卷积,有利于捕捉更大范围的上... 详细信息

为了捕捉遥感影像中丰富的上下文信息与多尺度的地物信息,改进集成模型的策略,提高语义分割精度,提出一种融合周期递增余弦退火与多尺度空洞卷积的高分辨率遥感影像语义分割方法。方法引入多尺度并行的空洞卷积,有利于捕捉更大范围的上下文信息,在不增加参数的情况下,提高网络对多尺度对象的辨识能力;使用全连接条件随机场引入空间和边缘的上下文信息,提高网络对遥感影像的细节分割能力;引入周期递增的余弦退火策略调整学习率,获得合适数量的局部最优解,集成局部最优解进一步提升网络在像素上的分类能力。在Gaofen Image Dataset数据集上的实验结果表明,多尺度并行空洞卷积可以充分捕捉遥感影像上的多尺度地物信息,能有效辨识复杂对象;空间和边缘上下文信息的引入使语义分割对象的边界辨识更精准;周期递增余弦退火策略能明显减少集成模型的推理时间,模型的总体精度与Kappa系数均优于目前主流的语义分割模型。

关键词：高分辨率遥感影像语义分割周期递增余弦退火多尺度并行空洞卷积目标提取上下文学习条件随机场多尺度学习

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碳纤维增强复合材料层合板的抗冲击性能

高压物理学报 2020年第2期34卷 57-64页

作者：李汶蔚梅杰黄威中国原子能科学研究院北京102413 华中科技大学船舶与海洋工程学院湖北武汉430074

为了研究碳纤维增强环氧树脂基复合材料层合梁的抗冲击性能,应用金属泡沫弹撞击加载的方式,结合高速摄像机,对等厚度层合梁结构的动态响应和失效行为展开实验研究。研究不同冲击加载强度对层合梁的动态失效过程、变形轮廓、中点变形、... 详细信息

为了研究碳纤维增强环氧树脂基复合材料层合梁的抗冲击性能,应用金属泡沫弹撞击加载的方式,结合高速摄像机,对等厚度层合梁结构的动态响应和失效行为展开实验研究。研究不同冲击加载强度对层合梁的动态失效过程、变形轮廓、中点变形、失效模式及能量耗散比的影响。结果表明:随着冲击强度的增加,中点变形响应速度随之增加,层合梁变形模式由整体变形转变为局部变形,且局部化效应随之增加,并伴随严重的基体和纤维断裂失效。层合梁能量耗散比随冲击强度的增加而增加,并展现出与结构失效模式直接关联的弹性变形、中心断裂和完全失效3个不同阶段。

关键词：冲击载荷碳纤维复合材料动态响应失效模式

Genome assembly and transcriptome analysis provide insights into the antischistosome mechanism of Microtus fortis

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Journal of Genetics and Genomics 2020年第12期47卷 743-755页

作者： Hong Li Zhen Wang Shumei Chai Xiong Bai Guohui Ding Yuanyuan Li Junyi Li Qingyu Xiao Benpeng Miao weili Lin jie Feng Mingyue Huang Cheng Gao Bin Li wei Hu Jiaojiao Lin Zhiqiang Fu Jianyun Xie Yixue Li Bio-Med Big Data Center CAS Key Laboratory of Computational BiologyShanghai Institute of Nutrition and HealthUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200031China Shanghai Veterinary Research Institute Chinese Academy of Agricultural SciencesKey Laboratory of Animal ParasitologyMinistry of AgricultureShanghai 200241China Shanghai Laboratory Animal Research Center Shanghai 201203China Institute for Digital Health International Human Phenome Institutes(Shanghai)Shanghai 200433China Shanghai Center for Bioinformation Technology Shanghai Academy of Science and TechnologyShanghai 201203China School of Computer Science and Technology Harbin Institute of Technology(Shenzhen)ShenzhenGuangdong 518055China Shanghai Institute of Immunology Department of Immunology and MicrobiologyShanghai JiaoTong University School of MedicineShanghai 200025China State Key Laboratory of Genetic Engineering Ministry of Education Key Laboratory of Contemporary AnthropologyCollaborative Innovation Center for Genetics and DevelopmentSchool of Life SciencesFudan UniversityShanghai 200438China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhouZhejiang 330106China

Microtus fortis is the only mammalian host that exhibits intrinsic resistance against Schistosoma japonicum ***,the underlying molecular mechanisms of this resistance are not yet ***,we perform the first de novo genome assembly of ***,comprehensive gene annotation analysis,and evolution ***,we compare the recovery rate of schistosomes,pathological changes,and liver transcriptomes between *** and mice at different time points after *** observe that the time and type of immune response in *** are different from those in *** activates immune and inflammatory responses on the 10th day post infection,such as leukocyte extravasation,antibody activation,Fc-gamma receptor-mediated phagocytosis,and the interferon signaling cascade,which play important roles in preventing the development of *** contrast,an intense immune response occurrs in mice at the late stages of infection and could not eliminate *** mice suffer severe pathological injury and continuous decreases in cell cycle,lipid metabolism,and other *** findings offer new insights into the intrinsic resistance mechanism of *** against schistosome *** genome sequence also provides the basis for future studies of other important traits in ***.

关键词： Genome assembly Microtus fortis Schistosome Immune Transcriptome

Developmental patterns of serum leptin levels, leptin gene expression in adipose tissue and Ob-Rb gene expression in hypothalamus of Erhualian and Large White pigs

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Science China(Life Sciences) 2004年第2期47卷 190-196页

作者： ZHOU jie’ 2, ZHAO Ruqian1, wei Xihui1, XIA Dong1, XU Qingfu1 & CHEN jie1 1. Key Laboratory of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China 2. Anhui Agricultural University, Hefei 230036, China 1. Key Laboratory of Animal Physiology and Biochemistry Ministry of Agriculture Nanjing Agricultural University 210095 Nanjing China 2. Anhui Agricultural University 230036 Hefei China

The present study was aimed to investigate the developmental patterns of leptin mRNA expression in dorsal subcutaneous adipose tissue and Ob-Rb mRNA expression in hy[(-)-23.8( )]pothalamus in pigs of different breeds and sexes. [(Erhualian gilts and boars and Large White)0( )]boars were sampled at birth, 3, 20, 30, 45, 90, 120 and 180 days of age, respectively. Serum concentration of leptin was measured with RIA and single tube semi-quantitative RT-PCR was applied to determine the relative abundances of mRNA expression using 18S rRNA as an internal standard. The results showed that leptin mRNA expression in adipose tissue increased with age and displayed both sex and breed differences. In Erhualian pigs, females expressed higher leptin mRNA compared with males, and Erhualian boars showed higher abundance of leptin mRNA than Large White boars (P < 0.01). Serum leptin levels were in good agreement with adipose leptin mRNA, displaying similar sex and line differences. In contrast, expression of Ob-Rb mRNA in hypothalamus exhibited a distinctive pattern, decreased gradually after birth, and then in[(-)23.8( )][(creased till weaning. )0(After weaning, Ob)0(-)]Rb gene expression decreased gradually with age but rose gradually again from 120 to 180 days of age in Erhualian pigs. [(The expression of Ob)0(-)(Rb)( )]mRNA was higher in Large White pigs than that in Erhualian pigs (P< 0.01). The results suggest that the serum leptin level and leptin gene expression in adipose tissue highly correlate with [(adiposity.)0( )]

关键词： pigs, adipose tissue, hypothalamus, leptin, long form leptin recepter (Ob-Rb).

A Study of Soil Nutrients in the Terrace Field Changed from Mountain Slope in Three Gorges Reservoir Region

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Asian Agricultural Research 2016年第8期8卷 77-80页

作者： Guojian CHEN Chunjuan LI Chunli LI Juanjuan LI jie wei Hongwei DONG Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area/College of Geography and Tourism Chongqing Normal University

In order to accurately grasp the soil fertility in Three Gorges Reservoir Region after changing mountain slope into terrace field,we take Wushan County for example,and use the spatio-temporal substitution method to analyze the soil nutrient status and trend about the terrace field changed from mountain slope under different length of *** results show that the soil fertility is generally low in the study area,and according to the soil nutrient grading standards in the second national land survey,the average content of total nitrogen,available potassium,organic matter and available phosphorus reaches Standard III,Standard III,Standard IV and Standard V,respectively,and the spatial heterogeneity of soil nutrients is *** to the sloping land,the terrace field changed from mountain slope has increasing soil nutrients on the whole with the length of *** mean of various indicators about soil nutrients in the terrace field changed from mountain slope for 2 years is lower than in the sloping land,and there is the biggest difference in soil fertility,while the mean of various indicators about soil nutrients in the terrace field changed from mountain slope for 14 years shows a linear upward trend,and the difference in soil fertility decreases.

关键词： Changing mountain slope into terrace field Soil nutrients Three Gorges Reservoir Region

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库尔勒香梨无人机辅助授粉飞行作业参数优选

果树学报 2024年第1期41卷 162-173页

作者：位杰蒋媛谢宏江新疆生产建设兵团第二师农业科学研究所新疆铁门关841005

【目的】无人机授粉技术因作业效率高、雾化效果好、成本低、可有效减少病害传播等优点,近几年不断得到重视与应用。探究无人机辅助授粉不同作业参数下雾滴在库尔勒香梨树冠层中的沉积分布规律,为精准、高效授粉提供指导。【方法】应用... 详细信息

【目的】无人机授粉技术因作业效率高、雾化效果好、成本低、可有效减少病害传播等优点,近几年不断得到重视与应用。探究无人机辅助授粉不同作业参数下雾滴在库尔勒香梨树冠层中的沉积分布规律,为精准、高效授粉提供指导。【方法】应用四旋翼无人机在库尔勒香梨盛花期开展不同飞行路线、喷液量、雾化粒径、飞行高度、飞行速度对雾滴沉积分布的影响研究,筛选最佳作业参数。【结果】无人机沿行上飞行时,雾滴密度、沉积量和覆盖率在树体上层到下层依次降低,而行间飞行时,上层最少,中下层较多,在同一冠层均低于行上飞行的雾滴密度、沉积量和覆盖率;随着喷液量的增加,树冠各层的雾滴密度、沉积量和覆盖率也随之升高;随雾化粒径的增大,雾滴密度在香梨树同一冠层整体上呈现出逐渐降低的趋势,相同粒径下,雾滴密度从上层到下层逐渐降低;同一飞行高度下,雾滴密度、沉积量和覆盖率在树体冠层从上到下依次递减,随飞行高度的升高,雾滴密度在各冠层呈先降后升的趋势,覆盖率和沉积量在树冠上层整体上呈现逐渐降低的趋势,在树冠中层和下层呈现先降后升的趋势;不同飞行速度下树冠上层的雾滴密度、沉积量和覆盖率无明显差异,在中层和下层,随飞行速度的升高,雾滴密度、沉积量和覆盖率逐渐下降。【结论】当无人机沿行上飞行、喷液量45L×hm^(-2)、雾化粒径100μm、飞行高度离树冠顶部1m、飞行速度3m×s^(-1)时效果较优。研究结果为无人机辅助授粉的田间作业参数设置提供参考,也为制定基于农用无人机的梨树辅助授粉作业技术规范提供依据。

关键词：库尔勒香梨无人机辅助授粉作业参数优选

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Screening and Identification of A Probiotic from the Intestinal Tract of Mystus macropterus

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Animal Husbandry and Feed Science 2014年第6期6卷 331-333,344页

作者： Dan Yan Xiong wei Chen Yuankun Wu Pihong Zhu jie Zhao Bo Chongqing Fishery Sciences Research Institute Rural Development Department of Pujiang County Chongqing Shuangqiao Chiatai Co. Ltd.

A total of 25 strains were isolated from the intestinal tract of Mystus macropterus. The inhibitory effects of extracellular enzyme activity to common aquat- ic pathogenic bacteria were screened. A probiotic DQHY -7 strain was isolated, and its safety was detected. DQHY -7 strain was preliminarily identified by mor- phological observation, and physiological and biochemical test. Research results showed that DQHY -7 strain had relatively strong production capacities of amylase, cellulase and protease, and could restrict the growth of Escherichia coli, Aeromonas hydrophila and Pseudomonas fluorescens. Results of acute toxicity test showed that 1. 0 × 108 CFU/mL DQHY -7 bacterial suspension showed no pathogenicity to M. macropterus. According to the colony growth pattern and physiological-bio- chemical characteristics of DQHY -7, the strain was identified to be Bacillus subtilis. Research results showed that DQHY -7 strain could be used as a new candi- date strain for feeding microecologicalagent.

关键词： Mystus macropterus Bacillus sp Probiotic Screening Candidate strain

Numerical simulation of the effects of the impact velocity on the particle deposition characteristics in cold gas dynamic spraying

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Baosteel Technical Research 2011年第1期5卷 12-16页

作者： MENG Xianming ZHANG Junbao HAN wei LIANG Yongli YANG Xiaoping ZHAO jie School of Materials Science and Engineering Faculty of Mechanical Engineering Materials and Energy Dalian University of Technology Dalian 116024 China Advanced Technology Division Research InstituteBaoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

In this study, the effects of the impact velocity on the particle deposition characteristics in cold gas dynamic spraying （CGDS） of 304 stainless steel （SS） on an interstitial free （IF） steel substrate are numerical simulated by means of a finite element analysis （FEA）. The results have illustrated that when the particle impact velocity exceeds a critical value at which adiabatic shear instability of the particle starts to occur. Meanwhile, the fatten ratio and impact crater depth （or the effective contacting area ） increase rapidly. The particle-substrate bonding and deposition mechanism can be attributed to such an adiabatic shear deformation induced by both the compressive force and the slide friction force of particle. The critical velocity can be predicted by numerical simulation, which is useful to optimize the CGDS processing parameters for various materials.

关键词： numerical simulation cold gas dynamic spraying(CGDS) deformation particle impact velocity

丹江口水库真核浮游植物群落分布特征及其与环境因子的关系

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环境科学 2022年第11期43卷 5096-5105页

作者：贺玉晓买思婕任玉芬李卫国赵同谦马寅男河南理工大学资源环境学院焦作454000 中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085 北京市南水北调大宁管理处北京100442

浮游植物是湖库生态系统物质循环和能量流动的主要参与者,了解其群落组成对保护水生生态系统平衡具有重要意义.2021年6月在南水北调中线工程水源地丹江口水库淅川库区设置7个采样点,分4层分别在0.5、5、10和20 m处共采取28个样品.采用... 详细信息

浮游植物是湖库生态系统物质循环和能量流动的主要参与者,了解其群落组成对保护水生生态系统平衡具有重要意义.2021年6月在南水北调中线工程水源地丹江口水库淅川库区设置7个采样点,分4层分别在0.5、5、10和20 m处共采取28个样品.采用高通量测序测定真核浮游植物群落结构,分析真核浮游植物群落在水平和垂向上的分布特征.采用冗余分析探讨了浮游植物主要类群与环境因子的关系.结果表明:(1)库区真核浮游植物共12门68属,物种为甲藻-硅藻-绿藻型结构.水平方向上浮游植物群落差异较大,各采样点垂直方向上浮游植物丰度和多样性存在较大差异.宋岗、土门和党子口浮游植物群落多样性和丰度随水深增加呈下降趋势,其他采样点的浮游植物群落与水深关系趋势不明显.(2)硝氮(NO_(3)^(-)-N)、水深、溶解氧(DO)、pH和水温(WT)是影响库区浮游植物垂直分布的重要环境因子.环境因子对浮游植物门类影响各异,甲藻门与NO_(3)^(-)-N和水深呈负相关,与其他环境因子呈正相关;硅藻门与NO~--N和水深呈正相关,与其他环境因子呈负相关;绿藻门与WT、pH和DO呈负相关,与水深无明显相关性.

关键词：丹江口水库浮游植物群落结构环境因子高通量测序