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基于Sentinel-2的青铜峡灌区水稻和玉米种植分布早期识别

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干旱区地理 2024年第5期47卷 850-860页

作者：朱磊王科丁一民孙振源孙伯颜宁夏大学土木与水利工程学院宁夏银川750021 宁夏回族自治区黄河水联网数字治水重点实验室宁夏银川750021

及时准确地掌握灌区内作物种植分布对于灌溉水资源高效配置、农田精准管理具有重要指导意义。以宁夏青铜峡灌区为研究对象,利用多时相Sentinel-2卫星数据,通过水稻和玉米早期特征分析,提取关键的“水淹”信号和“植被”信号,构建时序归... 详细信息

及时准确地掌握灌区内作物种植分布对于灌溉水资源高效配置、农田精准管理具有重要指导意义。以宁夏青铜峡灌区为研究对象,利用多时相Sentinel-2卫星数据,通过水稻和玉米早期特征分析,提取关键的“水淹”信号和“植被”信号,构建时序归一化差异水体指数(MNDWI)和归一化植被指数(NDVI)特征值数据集,并通过样本分析关键特征阈值,构建水稻和玉米早期种植分布决策树模型,提取2022年宁夏青铜峡灌区水稻和玉米种植的空间分布。结果表明(:1)玉米和水稻苗期的后半段5月15—31日,水淹信号和植被信号是区分二者关键时期。(2)基于早期作物物候特征的方法,在5月16—31日获取的水稻和玉米图像制图精度高于90%,用户精度超过91%,总体精度超过90%,Kappa系数高于0.88,明显高于同时期随机森林方法的分类精度。(3)本研究提出的方法在早期水稻和玉米种植分布提取方面具有较强的适用性,并且能够在时空尺度上以较少的实地样本进行延展,同时在时间上也更有优势。因此,该方法为青铜峡灌区水稻和玉米种植分布早期调查提供了重要的方法支撑。

关键词：青铜峡灌区 Sentinel-2 归一化植被指数归一化差异水体指数决策树水稻玉米

On line parameter estimation based on gradient algorithm for fractional order systems

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Journal of Control and Decision 2015年第4期2卷 219-232页

作者： Yiheng Wei zhenyuan sun Yangsheng Hu Yong Wang Department of Automation University of Science and Technology of ChinaHefeiP.R.China School of Environmental Science and Optoelectronic Technologies University of Science and Technology of ChinaHefeiP.R.China

This article investigates the problem of on line parameter estimation for fractionalorder linear *** on the theory of fractional-order calculus,the conventional gradient estimator is extended to the fractional-order *** stability of the estimator and the convergence are analysed using the continuous frequency distributed model and indirect Lyapunov ***,numerical simulation examples are given to demonstrate the effectiveness of the proposed schemes.

关键词： fractional-order systems gradient estimator indirect Lyapunov method continuous frequency distributed model

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捧心兰新品种‘红林舞’

园艺学报 2024年第7期51卷 1713-1714页

作者：李振坚张素枝邹小硕常玲玲周瑜鑫孙振元邹竣竹中国林业科学研究院林业研究所国家林业和草原局林木培育重点实验室林木遗传育种国家重点实验室北京100091 滁州路宽生物技术有限公司安徽滁州239202

捧心兰‘红林舞’是以‘红宝石’(Lycaste‘Red Jewel’)为母本,芳香薄叶兰(***)为父本,通过人工杂交选育而成的新品种。其花色深紫红(RHS 59B),色调均匀,花形圆整,小巧,平均单株花1~5朵,花梗长8~13 cm,花径4.5~5.5 cm。花期为12月底至... 详细信息

捧心兰‘红林舞’是以‘红宝石’(Lycaste‘Red Jewel’)为母本,芳香薄叶兰(***)为父本,通过人工杂交选育而成的新品种。其花色深紫红(RHS 59B),色调均匀,花形圆整,小巧,平均单株花1~5朵,花梗长8~13 cm,花径4.5~5.5 cm。花期为12月底至翌年2月中,适宜中国北方温室和南方露天栽培。

关键词：捧心兰红花杂交品种

Transfer DREB into Lolium perenne L. to improve its drought tolerance

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High Technology Letters 2006年第4期12卷 427-433页

作者：马欣荣 sun zhenyuan Jiang Changshun Dong Zhaoyong Zhang Yizheng College of Life Sciences Sichuan University Chengdu 610064 P.R. China Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041 P.R. China Research Institute of Forestry Chinese Academy of Forestry Beijing 100091 P.R. China

A method of Agrobacterium tumefaciens mediated transformation for perennial ryegrass was developed using the calli of ryegrass derived from mature enrbryos. The calli were inoculated with a disarmed A. tumefaciens strain EHA105 harboring binary vector p2328. Vector p2328 contained transcription factor DREB1B and neomycin phosphotransferase （npt H） genes which were driven by promoters of rd29B and CaMV35S, respectively. The inoculated calli were selected on paromomycin- or kanamycin-containing media till the established plants being transferred to soil. Six tmnsgenic plants with DREB1B had been obtained from perennial ryegrass strain Tove. PCR and Southern-blotting showed that npt Ⅱ and DREBIB genes were integrated in perennial ryegrass genome. Stress treatment confirmed that transgenic plants with higher drought tolerance were obtained.

关键词： Lolium perenne. L Agrobacterium tumefaciens binary plasmid transcription factor DREB1 B gene transformation

Self-cleaning effect and secondary swirling clean gas for suppressing particle deposition on vortex finder of gas cyclones

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Particuology 2024年第7期90卷 72-87页

作者： Zhanpeng sun Huandi Yang Kaixuan Zhang Zhiyuan Wang zhenyuan Hong Guang Yang School of Mechanical Engineering Hebei University of Science&TechnologyShijiazhuang050018China

In order to suppressing the particle deposition on vortex finder,a series of gas cyclones with the secondary swirling clean gas were developed inspired by the gas purge *** of the width and extension length of the flow channel as well as the secondary inlet velocity and running time on the particle deposition pattern,the deposited particle mass and the cyclones'performance were experimentally investigated,*** results show that the ultrafine particles(Stokes number Stk<0.0358)are mainly loose deposited on the walls under the secondary *** to the conventional cyclone with single tangential inlet,the total deposited particle mass of the improved cyclone has a maximum reduction more than 60%,and the collecting efficiency is increased up to 97.5%under the basically same pressure *** corresponding no-deposition area is increased by about 13%,and remains constant in spite of extending the running ***,an interesting phenomenon named"self-cleaning effect"of the vortex finder was captured for the gas cyclones,and mechanism of the secondary clean gas on the particle deposition is preliminarily *** results can deepen the understanding of the particle deposition on the vortex finder and guide the design of the anti-coking gas cyclones.

关键词： Cyclones Vortex finder Particle deposition Gas purge effect Self-cleaning effect

Electricity Theft Detection Method Based on Ensemble Learning and Prototype Learning

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 213-224页

作者： Xinwu sun Jiaxiang Hu zhenyuan Zhang Di Cao Qi Huang Zhe Chen Weihao Hu the School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengduChina Southwest University of Science and TechnologyChengduChina

With the development of advanced metering infrastructure(AMI),large amounts of electricity consumption data can be collected for electricity theft ***,the imbalance of electricity consumption data is violent,which makes the training of detection model *** this case,this paper proposes an electricity theft detection method based on ensemble learning and prototype learning,which has great performance on imbalanced dataset and abnormal data with different abnormal *** this paper,convolutional neural network(CNN)and long short-term memory(LSTM)are employed to obtain abstract feature from electricity consumption *** calculating the means of the abstract feature,the prototype per class is obtained,which is used to predict the labels of unknown *** the meanwhile,through training the network by different balanced subsets of training set,the prototype is *** with some mainstream methods including CNN,random forest(RF)and so on,the proposed method has been proved to effectively deal with the electricity theft detection when abnormal data only account for 2.5%and 1.25%of normal *** results show that the proposed method outperforms other state-of-the-art methods.

关键词： Electricity theft detection ensemble learning prototype learning imbalanced dataset deep learning abnormal level

Unraveling the mechanism of potassium metal capacitor for highly efficient charge storage

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Science China Chemistry 2024年第5期67卷 1578-1588页

作者： Qianqian Yao Pei Tang Kunyao Peng zhenyuan Miao Yuecong Chen Qingyun Dou Xingbin Yan Department of Materials Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China South China Academy of Advanced Optoelectronics South China Normal UniversityGuangzhou 510006China

Although hybrid metal ion capacitors(MICs) are highly desired to achieve both high power density of supercapacitors and high energy density of rechargeable batteries, the mismatch problem of electrochemical kinetics of negative and positive electrodes in MICs hampers the realization of this goal. Here, a new hybrid capacitor concept-potassium metal capacitor(PMC) is proposed for the first time, where potassium metal and commercial activated carbon(AC) without any modification are applied as negative and positive electrodes, respectively, and the electrolyte is the same as that of non-aqueous potassium ion batteries. The simplest PMC prototype exhibits a good combination of high energy density(184.9 Wh kg^(-1)) and power density(12.4 kW kg^(-1)), which benefits from the synergistic effect of potassium metal and AC electrode. The former experiences fast potassium plating/striping during charging and discharging, and the later possesses complex multiple charge behaviors driven by low potential of potassium metal. Specifically, below open-circuit voltage, transportation of solvated cations in AC pores plays an important role;beyond this voltage, synergy actions of cations and anions, including adsorption/desorption of solvated cations and anions, and ions exchange between them, dominate the capacitance contribution. This work enriches the types of MICs, and deepens the understanding of the energy storage mechanism of non-aqueous hybrid metal capacitors.

关键词： hybrid capacitor potassium metal activated carbon charge storage mechanism

Gene Cloning and Expression of the Pyrroline-5-carboxylate Reductase Gene of Perennial Ryegrass(Lolium perenne)

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Horticultural Plant Journal 2015年第2期1卷 113-120页

作者： CAO Li WEI Shuqiang HAN Lei QIAN Yongqiang ZHANG Huali XIN Haibo sun zhenyuan Department of Horticulture and Landscape Yanbian University Key Laboratory of Tree Breeding and Cultivation State Forestry Administration/Research Institute of Forestry Chinese Academy of Forestry Beijing Key Laboratory of Greening Plants Breeding Beijing Institute of Landscape and Architecture

Salt and drought limit the range of applications of perennial ryegrass(Lolium perenne L.), which is one of the important turf and forage grasses. Previous studies have suggested that pyrroline-5-carboxylate reductase(P5CR) might play a central role in proline accumulation in plants that are responsive to stresses. In the present study, the Lolium perenne L. pyrroline-5-carboxylate reductase(LpP 5CR) gene was cloned from leaves of the cultivar ‘Derby' using the RACE technique. The full-length LpP 5CR gene was 1 047 bp in length, which comprised an open reading frame(ORF) of 840 bp in size. Sequence alignment revealed that the putative Lp P5 CR had a 94.3% similarity to Ta P5 CR. q RT-PCR displayed that the mR NA levels of the LpP 5CR gene were almost the same as that in the roots, stems, and leaves of perennial ryegrass seedlings subjected to normal condition or NaC l treatment for 1 h. Moreover, the transcription level of LpP 5CR was up- or down- regulated with Na Cl, polyethylene glycol(PEG), cold, or abscisic acid(ABA) treatment for 3 to 48 h. In addition, confocal microscopy localized the GFP-Lp P5 CR fusion protein to the cytoplasm of onion epidermal cells. These findings suggest that LpP 5CR encodes a cytoplasmic P5 CR protein that plays an important role in the response of perennial ryegrass to various stresses.

关键词： Lolium perenne pyrroline-5-carboxylate reductase proline subcellular localization gene expression

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渗灌水肥耦合对同心圆枣生长发育的影响

北京林业大学学报 2022年第2期44卷 22-29页

作者：孙振源焦炳忠李兴强宁夏大学土木与水利工程学院宁夏银川750021 宁夏水利科学研究院宁夏银川750021 宁夏大学教育部中阿旱区特色资源与环境治理国际合作联合实验室宁夏银川750021

【目的】本文旨在探究不同水肥耦合处理下旱区同心圆枣各因子的变化,阐明不同水肥耦合对促进枣树生长发育的影响。【方法】本文以8年生成龄枣树为研究对象,设置不同灌溉定额(W1:2250 m^(3)/hm^(2)、W2:3000 m^(3)/hm^(2)、W3:3750 m^(3)... 详细信息

【目的】本文旨在探究不同水肥耦合处理下旱区同心圆枣各因子的变化,阐明不同水肥耦合对促进枣树生长发育的影响。【方法】本文以8年生成龄枣树为研究对象,设置不同灌溉定额(W1:2250 m^(3)/hm^(2)、W2:3000 m^(3)/hm^(2)、W3:3750 m^(3)/hm^(2))、施氮水平(N1:240 kg/hm^(2)、N2:300 kg/hm^(2)、N3:360 kg/hm^(2))的2因素3水平试验,以探究地下渗灌水肥耦合对同心圆枣叶绿素含量(SPAD)、氮含量(C_(N))、产量、水分利用效率(WUE)、氮肥偏生产力(PFP)的影响。【结果】灌水量对枣树叶片的SPAD和C_(N)均有显著影响,但施氮量对枣树叶片的SPAD和C_(N)均无显著影响;随着灌水量和施氮量的增加,枣树叶片的SPAD和C_(N)的总趋势均表现为先增加后降低,W2N3处理的枣树叶片SPAD和C_(N)最高;水肥耦合对枣树单果质量、单株结果数、产量、水分利用效率和氮肥偏生产力均有显著影响,随着灌水量和施氮量的增加,先增加后降低,W2N2处理条件下的水分利用效率最高(2.54 kg/m^(3)),氮肥偏生产力最高(24.15 kg/kg),产量也最高(7246.26 kg/hm^(2)),与其他处理均达到显著性差异(P<0.05)。【结论】适宜的水肥耦合处理(W2N2)有利于提高旱区同心圆枣产量和水分利用效率及氮肥偏生产力,对同心圆枣生长发育有积极影响。

关键词：水肥耦合地下渗灌同心圆枣水分利用效率氮肥偏生产力生长发育