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广义非线性薛定谔方程解的构建

山西大学学报(自然科学版) 2024年第3期47卷 547-554页

作者：肖思宇孙峪怀韩梦娜黄宣聪四川师范大学数学科学学院

对广义非线性薛定谔方程的解进行了构建和研究。首先通过行波变换，将非线性薛定谔方程转化为常微分方程，并得到系统色散关系，再利用（G'/G;2;）展开法进行解的构造，构造出了广义非线性薛定谔方程的一系列精确解。同时表明所用方法... 详细信息

对广义非线性薛定谔方程的解进行了构建和研究。首先通过行波变换，将非线性薛定谔方程转化为常微分方程，并得到系统色散关系，再利用（G'/G;2;）展开法进行解的构造，构造出了广义非线性薛定谔方程的一系列精确解。同时表明所用方法和过程对构造非线性薛定谔方程的精确解具有有效性和适用性。

关键词：广义非线性薛定谔方程 (G'/G2)展开法精确解

双(G/G',1/G)展开法求解(3+1)维mKdvZK方程和(3+1)维YTSF方程的新孤子解

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内蒙古师范大学学报（自然科学汉文版） 2024年第1期53卷 1-9页

作者：杨超孙峪怀韩梦娜四川师范大学数学科学学院四川成都610066

研究(3+1)维修正Korteweg-devries-Zakharov-Kuznestsov方程和(3+1)维Yu-Toda-Sassa-Fukuymama方程的解。首先利用行波变换和代入变换将(3+1)维mKdvZKE和(3+1)维YTSFE转化为常微分方程,而后选择双(G/G’,1/G)展开法得到多个与现有的文献不同的精确解。本方法丰富了(3+1)维修正Korteweg-devries-Zakharov-Kuznestsov方程和(3+1)维Yu-Toda-Sassa-Fukuymama方程的解,说明所用方法和过程对构造非线性演化方程的精确解具有科学性和通用性。

关键词：双(G/G’ 1/G)展开法修正Korteweg-devries-Zakharov-Kuznestsov方程 Yu-Toda-Sassa-Fukuymama方程精确解

Frequency steering of spaceborne clocks based on XPNAV-1 observations

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Chinese Journal of Aeronautics 2023年第6期36卷 266-278页

作者： mengna han Minglei TONG Liansheng LI Yongqiang SHI Tinggao YANG Yuping GAO National Time Service Center Chinese Academy of SciencesXi'an 710600China Schoolof Astronomy and Space Science University of Chinese Academy of SciencesBejing 100049China Beijing Institute of Control Engineering Beijing 100190China

Due to high stable rotations, timing of pulsars provides a natural tool to correct the frequency deviation of spaceborne atomic clocks. Based on processing the observational data about a year of Crab pulsar given by XPNAV-1 satellite, we study the possibility of correcting the frequency deviation of spaceborne atomic clocks using pulsar timing. According to the observational data in X-ray band and the timing model parameters from radio observations, the pre-fit timing residuals with a level of 67.66 μs are obtained. By fitting the slope of the timing residuals affected by the faked frequency-biased reference clock, we estimated successfully the relative frequency deviation of the reference clock. For a satellite clock with frequency deviation of the order about 10^(-12), a calibration accuracy with relative error of about 2% can be obtained from the Crab pulsar’s data for one *** stability of the time scale based on Crab pulsar is about 10^(-12) for an interval of one year.

关键词： Pulsar time scale Pulsar timing Atomic clock Frequency steering X-ray observation

Real-time grain breakage sensing for rice combine harvesters using machine vision technology

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International Journal of Agricultural and Biological Engineering 2020年第3期13卷 194-199页

作者： Jin Chen Yi Lian Rong Zou Shuai Zhang Xiaobo Ning mengna han College of Mechanical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Breakage rate is one of the most important indicators to evaluate the harvesting performance of a combine *** is affected by operating parameters of a combine such as feeding rate,the peripheral speed of the threshing cylinder and concave clearance,and shows complex non-linear ***-time acquisition of the breakage rate is an effective way to find the correlation of *** addition,real-time monitoring of the breakage rate can help the driver optimize and adjust the operating parameters of a combine harvester to avoid the breakage rate exceeding the *** this study,a real-time monitoring method for the grain breakage rate of the rice combine harvester based on machine vision was *** structure of the sampling device was designed to obtain rice kernel images of high quality in the harvesting *** to the working characteristics of the combine,the illumination and installation of the light source were optimized,and the lateral lighting system was constructed.A two-step method of“color training-verification”was applied to identify the whole and broken *** the first step,the local threshold algorithm was used to get the edge of kernel particles in a few training images with binary transformation,extract the color spectrum of each particle in color-space HSL and output the recognition model *** second step was to verify the recognition accuracy and the breakage rate monitoring accuracy through grabbing and processing images in the *** experiments of about 2300 particles showed that the recognition accuracy of 96%was attained,and the monitoring values of breakage rate and the true artificial monitoring values had good trend *** monitoring device of grain breakage rate based on machine vision can provide technical supports for the intellectualization of combine harvester.

关键词： combine harvester breakage rate monitoring sampling box structure machine vision color classification

中国渔业经济发展质量的时空演化及影响因素研究

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中国渔业经济 2024年第2期42卷 54-66页

作者：刘洋夏娜王永正刘晨韩梦娜王梓睿大连海洋大学海洋法律与人文学院辽宁大连116023 大连海洋大学经济管理学院辽宁大连116023

文章以2011-2021年中国29个主要省(区、市)为研究对象,利用熵值法、泰尔指数分别测算渔业经济发展质量水平、区域渔业经济发展质量水平差异指数,运用地理探测器模型分析影响中国渔业经济发展质量的主要因素。结果显示:①中国渔业经济发... 详细信息

文章以2011-2021年中国29个主要省(区、市)为研究对象,利用熵值法、泰尔指数分别测算渔业经济发展质量水平、区域渔业经济发展质量水平差异指数,运用地理探测器模型分析影响中国渔业经济发展质量的主要因素。结果显示:①中国渔业经济发展质量水平呈上升态势,在空间上呈东部地区发展水平高西部地区发展水平低的状态。②中国区域渔业经济发展质量水平整体呈现出组内“东、西部差距高,中部、东北部差距低”的空间分布格局,总体差异来源区域内。③影响渔业经济发展质量的主要因子是渔业开放强度和渔业生态水平,渔业资源水平和渔业共享水平的影响力相对较弱。不同影响因子交互作用均表现双因子增强类型。

关键词：渔业经济高质量发展时空演化

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Phosphorylation Promotes the Accumulation of PERIOD Protein Foci

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Research 2024年第1期2023卷 59-69页

作者： mengna Li Shujing Li Luoying Zhang Key Laboratory of Molecular Biophysics of Ministry of Education College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanHubei 430074China Department of Life Sciences Bengbu Medical CollegeBengbuAnhui 233030China Hubei Province Key Laboratory of Oral and Maxillofacial Development and Regeneration WuhanHubei 430022China

Circadian clock drives the 24-h rhythm in our behavior and *** molecular clock consists of a series of transcriptional/translational feedback loops operated by a number of clock genes.A very recent study reported that the clock protein PERIOD(PER)is organized into discrete foci at the nuclear envelope in fly circadian neurons,which is believed to be important for controlling the subcellular localization of clock *** of inner nuclear membrane protein lamin B receptor(LBR)leads to disruption of these foci,but how they are regulated is yet ***,we found that PER foci are likely phase-separated condensates,the formation of which is mediated by intrinsically disordered region in *** promotes the accumulation of these *** phosphatase 2A,which is known to dephosphorylate PER,hampers the accumulation of the *** the other hand,the circadian kinase DOUBLETIME(DBT)which phosphorylates PER enhances the accumulation of the *** likely facilitates PER foci accumulation by destabilizing the catalytic subunit of protein phosphatase 2A,MICROTUBULE STAR(MTS).In conclusion,here,we demonstrate a key role for phosphorylation in promoting the accumulation of PER foci,while LBR modulates this process by impinging on the circadian phosphatase MTS.

关键词： conclusion separated translational

基于机器视觉的水稻杂质及破碎籽粒在线识别方法

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农业工程学报 2018年第13期34卷 187-194页

作者：陈进顾琰练毅韩梦娜江苏大学机械工程学院镇江212013

为了解决目前国内联合收获机缺乏针对含杂率、破碎率的在线监测装置的问题,该文提出基于机器视觉的水稻图像采集,杂质与破碎籽粒分类识别方法。采用带色彩恢复的多尺度Retinex算法增强原始图像,对HSV颜色模型的色调、饱和度两个通道分... 详细信息

为了解决目前国内联合收获机缺乏针对含杂率、破碎率的在线监测装置的问题,该文提出基于机器视觉的水稻图像采集,杂质与破碎籽粒分类识别方法。采用带色彩恢复的多尺度Retinex算法增强原始图像,对HSV颜色模型的色调、饱和度两个通道分别设定阈值进行图像分割,并结合形状特征得到分类识别结果。采用综合评价指标对试验结果进行量化评价,研究表明,茎秆杂质识别的综合评价指标值达到了86.92%,细小枝梗杂质识别的综合评价指标值为85.07%,破碎籽粒识别的综合评价指标值为84.74%,平均识别一幅图像的时间为3.24 s。结果表明,所提出的算法能够快速有效识别出水稻图像中的杂质以及破碎籽粒,为水稻含杂率、破碎率的在线监测提供技术支撑。

关键词：机器视觉图像处理杂质水稻破碎籽粒颜色模型在线识别

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基于U-Net模型的含杂水稻籽粒图像分割

农业工程学报 2020年第10期36卷 174-180页

作者：陈进韩梦娜练毅张帅江苏大学机械工程学院镇江212013

含杂率是水稻联合收获机的重要收获性能指标之一,作业过程中收获籽粒掺杂的杂质包含作物的枝梗和茎秆等,为了探索籽粒含杂率和机器作业参数之间的关联,需要实时获取籽粒含杂率数据。该文基于机器视觉的U-Net模型对联合收获机水稻收获籽... 详细信息

含杂率是水稻联合收获机的重要收获性能指标之一,作业过程中收获籽粒掺杂的杂质包含作物的枝梗和茎秆等,为了探索籽粒含杂率和机器作业参数之间的关联,需要实时获取籽粒含杂率数据。该文基于机器视觉的U-Net模型对联合收获机水稻收获籽粒图像进行分割,针对传统分割算法中存在运算量大、耗时多、图像过分割严重和分割参数依赖人为经验难以应对各种复杂谷物图像等问题,采用深度学习模型多次训练学习各分割类别的像素级图像特征,提出基于U-Net深度学习模型的收获水稻籽粒图像中谷物、枝梗和茎秆的分割方法,采用改进的U-Net网络增加网络深度并加入Batch Normalization层,在小数据集上获得更丰富的语义信息,解决图像训练数据匮乏和训练过拟合问题。选取田间试验采集的50张收获水稻籽粒图像,采用Labelme方式进行标注和增强数据,裁剪1000张256像素×256像素小样本,其中700张作为训练集,300张作为验证集,建立基于改进U-Net网络的收获水稻籽粒图像分割模型。采用综合评价指标衡量模型的分割准确度,对随机选取的60张8位RGB图像进行验证。试验结果证明,水稻籽粒的分割综合评价指标值为99.42%,枝梗的分割综合评价指标值为88.56%,茎秆的分割综合评价指标值为86.84%。本文提出的基于U-Net模型的收获水稻籽粒图像分割算法能够有效分割水稻籽粒图像中出现的谷物、枝梗和茎秆,时性更强、准确度更高,可为后续收获水稻籽粒图像的进一步识别处理提供技术支撑,为水稻联合收获机含杂率实时监测系统设计提供算法参考。

关键词：图像处理水稻杂质 U-Net网络模型

Application of plant DNA metabarcoding of lake sediments for monitoring vegetation compositions on the Tibetan Plateau

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Science China Earth Sciences 2024年第11期67卷 3594-3609页

作者： Kai WU Kai LI Weihan JIA Kathleen R.STOOF-LEICHSENRING Ulrike HERZSCHUH Jian NI mengna LIAO Fang TIAN College of Life Sciences Zhejiang Normal University Polar Terrestrial Environmental Systems Research Group Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research Institute of Environmental Science and Geography University of Potsdam Institute of Biochemistry and Biology University of Potsdam College of Resource Environment and Tourism Capital Normal University

Benefiting from the rapid development of environmental DNA(eDNA) technologies, sedimentary DNA(sedDNA)emerges as a promising tool for monitoring plant compositions in remote regions. The Tibetan Plateau(TP), renowned for its harsh environment and numerous ponds and lakes, presents a potentially demanding region for the application of sedDNA on vegetation investigations. Here, we used the g and h universal primers for the P6 loop region of the chloroplast trn L(UAA)intron to amplify plant DNA in surface sediments from 59 ponds and small lakes on the southwestern TP. The applicability and limitations of using plant DNA metabarcoding for modern vegetation monitoring and palaeo-vegetation reconstructions have been assessed by comparing sedDNA, pollen, and vegetation survey data. Our results showed that plant DNA metabarcoding recorded 186 terrestrial taxa, of which 30.1% can be identified at the species level. The plant sedDNA approach can effectively disclose the dominant plant taxa(including Asteraceae, Cyperaceae and Poaceae) and significant vegetation assemblages in the vicinity of the investigated sites. The number of taxa and taxonomic resolution of plant sedDNA exceeded that of pollen analysis(75 taxa detected, 5.3% can be identified at species level). Unlike pollen that retains a broad spectrum of regional plant signals(including Pinus and Artemisia), plant sedDNA mirrors very local plants, underscoring its utility in local vegetation monitoring and reconstructions. To conclude, plant DNA metabarcoding of(small) lake sediments warrant increased attention in the future for local vegetation monitoring and reconstructions on the TP.

关键词： Sedimentary DNA (sedDNA) Metabarcoding Pollen Vegetation composition Tibetan Plateau