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基于BEMD的电力设备红外与可见光图像的配准研究

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电力系统保护与控制 2011年第23期39卷 25-29页

作者：赵振兵王琴余萍王飒飒华北电力大学电气与电子工程学院河北保定071003

电力设备的红外图像和可见光图像从不同角度反映了设备的状态,对它们进行配准可以提高在线监测的准确性。将2维经验模态分解(BEMD)方法引入到电力设备的红外与可见光图像配准中。通过理论分析得出了基于BEMD的图像配准原理,把图像的配... 详细信息

电力设备的红外图像和可见光图像从不同角度反映了设备的状态,对它们进行配准可以提高在线监测的准确性。将2维经验模态分解(BEMD)方法引入到电力设备的红外与可见光图像配准中。通过理论分析得出了基于BEMD的图像配准原理,把图像的配准问题转化成了BEMD分解后子图像的配准问题,并确定了原始图像、趋势图像及2维仿射变换在配准中的关系;基于此原理提出了一种红外与可见光图像配准方法。实验结果表明该方法可取得良好的配准效果,同时也验证了该配准原理的正确性和方法的先进性。

关键词： 2维经验模态分解图像配准红外图像可见光图像电力设备小波分解

Assessing Landsat-8 atmospheric correction schemes in low to moderate turbidity waters from a global perspective

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International Journal of Digital Earth 2023年第1期16卷 66-92页

作者： Nanyang Yan zhen Sun Wei Huang Zhao Jun Shaojie Sun School of Marine Sciences Sun Yat-sen UniversityGuangzhouPeople’s Republic of China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) ZhuhaiPeople’s Republic of China Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering GuangzhouPeople’s Republic of China Pearl River Estuary Marine Ecosystem Research Station Ministry of EducationZhuhaiPeople’s Republic of China Key Laboratory of Natural Resources Monitoring in Tropical and Subtropical area of South China Ministry of Natural ResourcesGuangzhouPeople’s Republic of China

Atmospheric correction is one of the major challenges in ocean color remote sensing,thus threatening comprehensive evaluation of water quality within aquatic *** this study,five state-of-the-art atmospheric correction(AC)processors(***,C2RCC,iCOR,L2gen,and Polymer)were applied to Operational Land Imager(OLI)Landsat-8 scenes and evaluated against in situ measurements across various types of waters worldwide.A total of 262 matchups between in situ measured and satellite-derived remote sensing reflectance(R_(rs))at 20 sites were obtained between August 2013 and August *** of optical water types(OWTs)was carried out using in situ measurements with matched satellite ***-specific analysis demonstrated that L2gen produced the most accurate Rrs with R^(2)≥0.74 and root mean squared error(RMSE)≤0.0018 sr^(–1) for the four visible bands of OLI,followed by Polymer,C2RCC,iCOR,and *** terms of R_(rs) spectral similarity,C2RCC yielded the lowest spectral angle(sa)of 8.55°,followed by L2gen(sa=9.20°).The advantage and disadvantage of each AC scheme were *** to improve the accuracy for atmospheric correction were made,such as polarization observations and concurrent aerosol and ocean color measurements.

关键词： Atmospheric correction Landsat-8 oceancolor remote sensing reflectance

基于个性化推送服务的数字图书馆学习资源提取

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图书与情报 2019年第5期 103-108页

作者：萨支斌许震闽江学院图书馆福建福州350108 中国科学技术信息研究所北京100038

文章针对当前研究成果存在的用户满意度和响应效率较低等问题,文章提出了基于个性化推送服务的数字图书馆学习资源提取方法。对用户资源下载信息、访问URL内容以及系统访问时间等数据进行采集,选择小型日志文件解析工具直接针对采集到... 详细信息

文章针对当前研究成果存在的用户满意度和响应效率较低等问题,文章提出了基于个性化推送服务的数字图书馆学习资源提取方法。对用户资源下载信息、访问URL内容以及系统访问时间等数据进行采集,选择小型日志文件解析工具直接针对采集到的数据进行相应解析,将解析得到的数据保存至MySQL或Oracle数据库;依据读者个性化行为数据采集与处理结果,利用等价矩阵下的聚类法对数字图书馆访问用户开展模糊聚类,利用最优聚类中用户浏览与借阅及资源利用情况为用户提供个性化推送服务;利用模糊识别方法识别目标用户个体状况,根据识别结果作为用户检索资源反馈给用户,实现学习资源提取。实验测试结果表明,该数字图书馆学习资源提取方法的性能较为完善,用户满意度较高,且响应速度更快,提取准确性高,表现出了良好的应用性能。

关键词：个性化推送数字图书馆资源提取个性化行为数据模糊识别

Growth,Cadmium and Zinc Accumulation of Ornamental Sunflower (Helianthus annuus L.) in Contaminated Soil with Different Amendments

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Pedosphere 2012年第5期22卷 631-639页

作者： HAO Xiu-zhen ZHOU Dong-Mei LI Dan-Dan JIANG Ping Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China)

Use of ornamental plants for phytoremediation of metal-contaminated soil is a new option. A pot experiment was carried out to assess the effect of application of amendments, i.e., swine manure, salicylic acid （sa） and potassium chloride （KC1）, on the growth, uptake and translocation of cadmium （Cd） and zinc （Zn） of ornamental sunflower （Helianthus annuus L.） grown on a contaminated soil. The three amendments increased sunflower height, flower diameter, and biomass. Manure significantly decreased Cd and Zn concentrations in sunflower, and thus decreased the bioaccumulation coefficient （BCF） of Cd and Zn. However, using of KC1 markedly increased Cd concentrations in sunflower and the BCF of Cd. Additionally, both swine manure and KC1 application increased Cd and Zn translocation from root to aboveground part. Swine manure and salicylic acid reduced the Cd/Zn ratios in flower of sunflower, while KC1 significantly increased the Cd/Zn ratios. Correlation analysis demonstrated that the Cd/Zn ratio in the root of sunflower was affected by K/Na ratio in root and soil available potassium （K） concentration. Ornamental sunflower could be grown as an alternative plant in the Cd- and Zn-contaminated soil with KC1 application to get the balance between environmental and economic interests.

关键词： Cd/Zn ratio fertilizer heavy metals manure remediation

Evaluation of the effect of hydrogen sulfide postconditioning by p-v loop against myocardial i/r injury in rats

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岭南心血管病杂志 2011年第S1期17卷 216-216页

作者： PENG Cheng-hai~1,CHENG Jia-li~1,SUN Xin~1,WANG Teng-yu~1, YANG Li-ming~2,T1AN zhen~2,SHI sa~2,TIAN Ye1 (1.Department of Cardiology,The First Affiliated Hospital, Harbin Medical University,Harbin 150086,China 2.Department of Pathophysiology,Harbin Medical University,Harbin 150086,China)

Objectives To evaluate the effect of hydrogen sulfide(H2S) postconditioning on myocardial ischemia-reperfusion (I/R) by pressure-volume loop(P-V loop). Methods The I/R model of rat in vivo was established by ligating the left anterior descending coronary artery for 30min and reperfusing for 120 *** rats(n=32) were ran- domly divided into 4 groups;Sham operation,ischemia-reperfusion (I/R),Ischemic postconditioning(IPO) and H2S *** sham operation,there was no *** IPO,at the start of reperfusion,three cycles of 30s reperfusion and 30s LAD reocclusion preceded the 3h of reperfusion. In H2S postconditioning,NaHS(15μmol/kg,Sodium hydrosulfide)was administrated before coronary artery reperfusion. The heart rate(HR),I/R arrhythmia,the left ventricular end-systolic pressure(LVESP),left ventricular enddiastolic pressure(LVEDP),the slope of the end- systolic P-V relation(ESPVR) and the slope of the end-diastolic P-V relation(EDPVR) were *** size was determined by scanning the images of the rat heart ventricular sections stained with Evans blue and *** Compared with I/R group,the I/R arrhythmia and the infarct size were decreased significantly(PPP2S postconditioning *** Myocardial I/R injury was decreased by H2S post-conditioning, and it was sensitive and accurate to evaluate the heart function by P-V loop.

关键词： Evaluation of the effect of hydrogen sulfide postconditioning by p-v loop against myocardial i/r injury in rats

Numerical Simulation of Microstructure Evolution for sa508-3 Steel during Inhomogeneous Hot Deformation Process

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Journal of Iron and Steel Research International 2014年第11期21卷 1022-1029页

作者： Da-shan SUI Fei CHEN Pei-pei ZHANG zhen-shan CUI National Die & Mold CAD Engineering Research Center Shanghai Jiao Tong University

Based on hot compression tests by a Gleeble-1500D thermo-mechanical simulator, the flow stress model and microstructure evolution model for sa508-3 steel were established through the classical theories on work hardening and softening. The developed models were integrated into 3D thermal-mechanical coupled rigid plastic finite element software DEFORM3D. The inhomogeneous hot deformation （IHD） experiments of sa508 3 steel were designed and carried out. Meanwhile, numerical simulation was implemented to investigate the effect of temperature, strain and strain rate on microstructure during IHD process through measuring grain sizes at given positions. The simulated grain sizes were basically in agreement with the experimental ones. The results of experiment and simulation demonstrated that temperature is the main factor for the initiation of dynamic recrystallization （DRX）, and higher temperature means lower critical strain so that DRX can be facilitated to obtain uniform fine microstructure.

关键词： sa508-3 steel inhomogeneous hot deformation microstructure evolution grain size numerical simulation

Accelerated kinetics of alkaline hydrogen evolution/oxidation reactions on dispersed ruthenium sites through N and S dual coordination

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Science China Chemistry 2022年第3期65卷 611-618页

作者： zhen Zhang Liwen Ni Haijun Liu Zhi-Liang Zhao Xiao-Zi Yuan Hui Li School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Department of Materials Science and Engineering Shenzhen Key Laboratory of Hydrogen EnergySouthern University of Science and TechnologyShenzhen 518055China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055China Research Center of Energy Mining and EnvironmentNational Research Council Canada4250 Wesbrook MallVancouver V6T1W5Canada

Efficient,robust and cost-effective electrocatalysts that catalyze hydrogen evolution/oxidation reaction(HER/HOR)in alkaline media are highly ***,single-atom catalysts(saCs)have emerged as new promising candidates;however,the rational design of supports and the optimization of coordination environment between supports and metal atoms are *** this work,we successfully fabricate atomically dispersed ruthenium(Ru)species,which are strongly coordinated by N and S dual heteroatoms on holey graphene(Rusa/NSG),as an excellent bifunctional catalyst for HER/*** alkaline media,the developed catalyst exhibits high catalytic performance with a low overpotential of 57.3 mV to drive a current density of 10 mA cm^(-1) for HER,and its mass activity is about 5.8 times higher than that of commercial Pt/C and Ru/C catalysts at an overpotential of 100 ***,considerable HOR performance of Ru sa/NSG is verified to be superior to Pt/C and Ru/***,X-ray-based spectroscopy measurements and density-functional theory calculations have confirmed that,compared with Ru–N_(4),the tailored Ru–N_(4)–S_(2) with nearby S dopants can act as more active centers to greatly accelerate the sluggish HER/HOR kinetics in alkaline *** present work provides a new atomic-level engineering strategy to modulate catalytic activities of saCs via the coordination design using dual heteroatoms on the carbon support.

关键词： single-atom catalyst ruthenium hydrogen evolution reaction hydrogen oxidation reaction density-functional theory

Effect of Mn content on microstructure, tensile and impact properties of sa508Gr.4N steel for reactor pressure vessel

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Journal of Iron and Steel Research International 2020年第4期27卷 461-470页

作者： Xi-kou He Zhi-qiang Yang zhen Wang Shi-bin Qiao zheng-dong Liu Institute for Special Steels Central Iron and Steel Research InstituteBeijing 100081China Technology Center of Ma’anshan Iron and Steel Co. Ltd.Ma’anshan 243000AnhuiChina

The effect of manganese(Mn)on the microstructure,tensile and impact properties of sa508Gr.4N steel has been experimentally *** influence of Mn content on the substructure of sa508Gr.4N steel was investigated using the scanning electron microscope,electron back-scattered diffractometer and transmission electron *** was found that the increased Mn content had a beneficial effect on both strength and *** of microstructure revealed smaller size of block and larger number of high-angle grain boundaries with higher Mn *** change of the ultimate tensile strength and toughness with increasing Mn content was attributed to the increased hardenability,the number of high-angle grain boundaries and the crack propagation path by the block refining.

关键词： Mn element sa508Gr.4N steel Microstructure Charpy impact toughness Substructure

The collision experiment between rolling stones of different shapes and protective cushion in open-pit mines

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Journal of Mountain Science 2021年第5期18卷 1391-1403页

作者： ZHU Chun HE Man-chao KARAKUS Murat ZHANG Xiao-hu GUO zhen School of Earth Sciences and Engineering Hohai UniversityNanjing 210098China Engineering Research Center of Development and Management for Low to Ultra-Low Permeability Oil&Gas Reservoirs in West China Ministry of EducationXi'an Shiyou UniversityXi'an 710021China State Key Laboratory for Geomechanics&Deep Underground Engineering Beijing 100083China School of Civil Environmental and Mining EngineeringThe University of AdelaideAdelaide SA 5005Australia College of Civil Engineering Tongji UniversityShanghai 200092China

Though gravel cushions are used worldwide in open-pit mines and railway slopes to control the impact of rolling stones,no universal technical standards have been put in place to guide engineers in their correct design,and few laboratory test results are available with which to characterize collisions between rolling stones and a gravel *** carried out a large number of experiments in which rolling stones made of the same material but differently shaped were dropped from various heights onto cushions with various particle sizes and *** investigated the characteristics of the resulting collisions,and the relationships between coefficients of restitution(CORs)of blocks with different shape and release height H,cushion thickness h and particle diameter d are obtained through linear fitting *** testing reveals the relative influence of block shape,release height,and the particle size and thickness of the cushion on the collision characteristics,which can assist engineers in designing a gravel cushion suitable to the distribution and weathering characteristics of rolling stones in a specific area.

关键词： Coefficient of restitution(COR) Collision characteristics Gravel cushion Rolling stone shape