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Modeling of maize gross primary production using MODIS imagery and flux tower data

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International Journal of Agricultural and Biological Engineering 2016年第2期9卷 110-118,I0004,I0005页

作者： Li Shihua He ping Liu Baosheng ni ping Han Xing School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 611731China School of Resources and Environment Jilin Agricultural UniversityChangchun 130018China

Maize is one of the most important crops cultivated on the global *** estimation of maize Gross Primary Production(GPP)can provide valuable information for regional and global carbon budget *** site level to regional/global scales,GPP estimation depends on remote sensing or eddy covariance flux *** this research,the 8-day composite GPP of maize was estimated by Moderate Resolution Imaging Spectroradiometer(MODIS)and flux tower data at eight study sites using a Regional Production Efficiency Model(REG-PEM).The performance of the model was assessed by analyzing the linearly regression of GPP estimated from the REG-PEM model(GPPEST)with the GPP predicted from the eddy covariance data(GPPEC).The coefficient of determination,root mean squared error and mean absolute error of the regression model were *** uncertainties of the model are also discussed in this *** seasonal dynamics(phases and magnitudes)of the GPPEST reasonably agreed with those of GPPEC,indicating the potential of the satellite-driven REG-PEM model for up-scaling the GPP in maize ***,the maize GPP estimated by this model is more accurate than the MODIS GPP products(MOD17A2).In particular,MOD17A2 significantly underestimated the GPP of maize *** uncertainties in the REG-PEM model are mostly contributed by the maximum light use efficiency and the fraction of photosynthetically active radiation.

关键词： gross primary production maize light use efficiency MODIS remote sensing flux datagross primary production maize light use efficiency MODIS remote sensing flux data

Decline in tree-ring growth of Picea mongolica and its intra-annual eco-physiological responses to drought and CO_(2) enrichment in semi-arid China

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Journal of Forestry Research 2024年第4期35卷 89-101页

作者： Xiaomin Zeng ping ni Xiaohong Liu Wenzhi Wang Yao Li Wenchao Wang School of Geography and Tourism Shaanxi Normal UniversityXi’an 710119People’s Republic of China The Key Laboratory of Mountain Environment Evolution and Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041People’s Republic of China CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Episodes of drought-induced decline in tree growth and mortality are becoming more frequent as a result of climate warming and enhanced water stress in semi-arid ***,the ecophysiological mechanisms under-lying the impact of drought on tree growth remains *** this study,earlywood and latewood tree-ring growth,δ^(13)C,andδ^(18)O chronologies of Picea mongolica from 1900 to 2013 were developed to clarify the intra-and inter-annual tree-ring growth responses to increasingly fre-quent *** results indicate that annual basal area increment residuals(BAI_(res)),which removed tree age and size effects,have significantly decreased since ***-ever,the decreasing trend of earlywood BAI_(res) was higher than that of *** response analysis suggests that the dominant parameters for earlywood and latewood proxies(BAI_(res),δ^(13)C andδ^(18)O)were drought-related climate variables(Palmer drought severity index,temperature,rela-tive humidity,and vapor pressure deficit).The most signifi-cant period of earlywood and latewood proxies’responses to climate variables were focused on June-July and July-August,***_(res),andδ^(13)C were significantly affected by temperature and moisture conditions,whereasδ^(18)O was slightly *** stomatal conduct-ance due to drought outweighed the influence of increasing CO_(2) on intrinsic water use efficiency(iWUE),and ultimately led to a decline in BAI_(res).Compared to latewood,the faster decreasing BAI_(res) and smaller increasing iWUE of early-wood suggested trees were more vulnerable to water stress in the early growing *** study provides insights into the inter-and intra-annual mechanisms of tree-ring growth in semi-arid regions under rising CO_(2) and climate change.

关键词： Tree growth Drought Water-use efficiency Seasonal differences Stable isotopes

Text duplication of papers in four medical related fields

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Journal of Data and Information Science 2023年第4期8卷 36-48页

作者： ping ni Lianhui Shan Yong Li Xinying An Institute of Medical Information Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100020China

Purpose:To reveal the typical features of text duplication in papers from four medical fields:basic medicine,health management,pharmacology and pharmacy,and public health and preventive *** analyze the reasons for duplication and provide suggestions for the management of medical academic ***/methodology/approach:In total,2,469 representative Chinese journal papers were included in our research,which were submitted by researchers in 2020 and 2021.A plagiarism check was carried out using the Academic Misconduct Literature Check System(AMLC).We generated a corrected similarity index based on the AMLC general similarity index for further *** compared the similarity indices of papers in four medical fields and revealed their trends over time;differences in similarity index between review and research articles were also analyzed according to the different *** analysis of 143 papers suspected of plagiarism was also performed from the perspective of sections containing duplication and according to the field of ***:Papers in the field of pharmacology and pharmacy had the highest similarity index(8.67±5.92%),which was significantly higher than that in other fields,except health *** similarity index of review articles(9.77±10.28%)was significantly higher than that of research articles(7.41±6.26%).In total,143 papers were suspected of plagiarism(5.80%)with similarity indices≥15%;most were papers on health management(78,54.55%),followed by public health and preventive medicine(38,26.58%);90.21%of the 143 papers had duplication in multiple sections,while only 9.79%had duplication in a single *** distribution of sections with duplication varied among different fields;papers in pharmacology and pharmacy were more likely to have duplication in the data/methods and introduction/background sections,however,papers in health management were more likely to contain duplication in the introduction/background or resul

关键词： Plagiarism Medical related fields Similarity index Sections containing duplication

Monitoring paddy rice phenology using time series MODIS data over Jiangxi Province,China

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International Journal of Agricultural and Biological Engineering 2014年第6期7卷 28-36,I0003页

作者： Li Shihua Xiao Jiangtao ni ping Zhang Jing Wang Hongshu Wang Jingxian School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu611731China The National Remote Sensing Center of China Beijing100036China

Paddy rice is one of the most important crops in the *** estimation and monitoring of paddy rice phenology is necessary for management and yield *** sensed time-series data are essential for estimation of crop phenology stages across large ***,the paddy rice phenological stages(i.e.,transplanting,tillering,heading,and harvesting)were detected in Jiangxi Province,China.A comparison study was conducted using ground observation data from 10 agricultural meteorological stations,collected between 2006 and *** phenological stages were detected using Moderate Resolution Imaging Spectroradiometer(MODIS)time-series enhanced vegetation index(EVI)***-Golay filter and wavelet transform were used to reduce the noise in the time-series EVI data and reconstruct the smoothed EVI time-series *** phenological stages of double-cropping rice were detected using the characteristics of the smoothed EVI *** root mean square errors(RMSEs)for each stage were ±10 days around the ground observation *** results suggest that Savitzky-Golay filter and wavelet transform are promising approaches for reconstructing high-quality EVI time-series ***,the phenological stages of double-cropping rice could be detected using time-series MODIS EVI data smoothed by Savitzky-Golay filter and wavelet transform.

关键词： remote sensing phenology paddy rice time series MODIS EVI growth monitoring Savitzky-Golay filter wavelet transform

Scheme of Weather-Based Indemnity Indices for Insuring Against Freeze Damage to Citrus Orchards in Zhejiang,China

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Agricultural Sciences in China 2009年第11期8卷 1321-1331页

作者： LOU Wei-ping QIU Xin-fa WU Li-hong ni Hu-ping TANG Qi-yi MAO Yu-ding Department of Atmospheric Science Nanjing University oflnformation Science ＆ Technology Nanjing 210044 P..R.China Xinchang Weather Bureau Xinchang 312500 P.R.China Zhejiang Provincial Climate Center Hangzhou 310017 P.R. China Division of Comprehensive Reform Development and Reform Commission of Zhejiang Province Hangzhou 310025 P.R. China College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 P.R.China

We design a weather-based indemnity index for the insurance against freeze damage to citrus orchards so as to provide technological support for the development of policy-based agriculture. The indices are prepared by separating a relative meteorological yield from the yield that is dependent on tree age, high-yield and low-yield years, and environmental factors, and then using a risk assessment scheme to determine the percentage yield reduction due to the meteorological hazard. We thus develop a set of indices associated with cold temperature damage with which to construct more severe weather indices in conjunction with the yield percentage decrease. We then combine the insured regional citrus yield index with the insured meteorological counterpart to obtain a weather-based indemnity index for the varying degree of freeze damage to crops. When the freeze damage index （FDI） is greater than -7.0℃ for the coastal belt of Zhejiang Province, China, or greater than -9.0℃ for other regions of Zhejiang, weather-based indemnity index （WBII） is zero, meaning there is no compensation; when the FDI is from -7.0 to -7.9℃ for the coastal belt or from -9.0 to -9.9℃ for other regions, the WBII is 1 with 50% compensation; when the FDI is from -8.0 to -8.9℃ for the coastal belt or from -10.0 to -10.9℃ for other regions, the WBII is 2 with 70% compensation; and when the FDI is less than -9.0℃ for the coastal belt or less than -11.0℃ for other regions, the WBII is 3 with 90% compensation. The weather indemnity indices of insured orchards are developed in the interest of owners, thereby eliminating adverse selection and moral hazard issues and providing timely recompense from the insurer, and resolving the problem of high indemnity cost in agricultural insurance.

关键词： citrus orchard freeze damage agricultural insurance weather-based indemnity index

Evaluation of corticospinal tract injury with three-dimensional diffusion tensor tract in patients with acute cerebral infarction

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Neural Regeneration Research 2006年第8期1卷 725-728页

作者： Hui Xiao Ziqian Chen Biyun Zhang ping ni Department of Medical Imaging Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLAFuzhou 350025Fujian ProvinceChina

BACKGROUND:Three-dimensional diffusion tensor tract(DTT)is the newest imaging to describe the structure of white matter fiber in three-dimensions,it has great significance in dividing the concrete anatomic site of gray and white matter lesions,displaying the correlation with fibrous band and judging clinical prognosis,which is incomparable by other ***:To observe the conditions of corticospinal tract(CST)in acute cerebral ischemic stroke patients,and analyze the relationship between motor function and the severity of CST ***:A case-control ***:Department of Medical Imaging,Fuzhou General Hospital of Nanjing Military Area Command of Chinese ***:Fifteen patients with acute cerebral infarction were selected from Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA from February to December in *** all suffered from acute attack and motor disorder of hemiplegic limbs to different extent,and were conformed by CT or *** were 9 males and 6 females,aging 16-87 years old,the median age was 51.7 years,and all were right *** right-handed normal subjects,who were matched by age and sex with the patients in the cerebral infarction group,were selected from the relatives of patients and physicians of the Imaging Department as the control *** the subjects were informed and agreed with the ***:The patients with acute cerebral infarction and subjects in the control group received MR diffusion tensor imaging(DTI)with GE 1.5 T nuclear magnetic resonance system,fiber tracking with the software of dTV-Ⅱ.Fractional anisotropy(FA)maps and three-dimensional tractography of bilateral CST of all patients were ***,continuity and destroy of fibrous bands were *** the same time,muscle strength of ipsilateral hand of patients with cerebral infarction was measured with Brunnstrom *** correlation between the severity of CST injury and the muscle strength o

关键词： CST Evaluation of corticospinal tract injury with three-dimensional diffusion tensor tract in patients with acute cerebral infarction

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以课程建设为核心助力继续教育探析

教育教学论坛 2025年第4期 18-21页

作者：吴亚荣刘苹妮孙静娟空军工程大学空管领航学院陕西西安710051

针对现阶段制约军事人才能力提升的问题,围绕充分发挥继续教育中的课程资源优势,联合军地多方教育机构,用好发展成熟的高等继续教育资源,以课程体系建设为核心,以先进的课程建设技术——岗位知识图谱为支撑,以多种研究方法为保障,聚焦... 详细信息

针对现阶段制约军事人才能力提升的问题,围绕充分发挥继续教育中的课程资源优势,联合军地多方教育机构,用好发展成熟的高等继续教育资源,以课程体系建设为核心,以先进的课程建设技术——岗位知识图谱为支撑,以多种研究方法为保障,聚焦研究内容,以航空管制人才能力提升为例,提炼了军事人才快速、稳定、长远发展的应对之策。进而在实践层面,创建良好的学习环境和资源,助力学习型军营的建设,持续大力提升新型军事人才的综合能力。

关键词：继续教育课程建设军事人才能力提升

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油田伴生气乙烷回收工艺的改进和综合评价

石油工程建设 2025年第1期51卷 40-45页

作者：倪萍秦英高海涛孙春亮梁昌晶中国石油华北油田分公司第三采油厂河北沧州062550 华港燃气集团有限公司河北沧州062550 中国石油华北油田分公司第一采油厂河北沧州062550

油田伴生气处理常用的液相过冷工艺存在乙烷收率低、经济性差等缺点,为实现油田生产的节能降耗,提出了两种改进工艺LSP-1和LSP-2,在5种富气气质条件下,从能耗、㶲、冷箱及经济性等方面进行了对比。结果表明,在气质1条件下,LSP-1工艺和LS... 详细信息

油田伴生气处理常用的液相过冷工艺存在乙烷收率低、经济性差等缺点,为实现油田生产的节能降耗,提出了两种改进工艺LSP-1和LSP-2,在5种富气气质条件下,从能耗、㶲、冷箱及经济性等方面进行了对比。结果表明,在气质1条件下,LSP-1工艺和LSP-2工艺的总压缩功分别为8199 kW和8169 kW,与LSP工艺相比,分别降低了8.3%、8.6%;㶲损最大的设备单元为压缩机和膨胀机,约占总㶲损的50%以上,在气质1条件下,LSP-1工艺和LSP-2工艺的总㶲损分别降低了4.2%、7.7%;LSP-2工艺在总投资成本和投资回收期上略优于LSP-1工艺;两种改进工艺的节能降耗效果较好,其中LSP-2工艺的优越性更加明显,对伴生气的适应性更佳。

关键词：伴生气乙烷回收 LSP工艺能耗㶲冷箱

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用于软材料的中应变率LSHPB系统及应用

爆炸与冲击 2025年第03期45卷 3-12页

作者：徐沛栋倪萍杨宝蒋震宇刘逸平刘泽佳周立成汤立群华南理工大学土木与交通学院亚热带建筑科学国家重点实验室

生物软材料大多是高含水率的超软材料，其力学性能在宽应变率范围内随着应变率的提高而非线性增强。然而由于实验条件的限制，在中应变率下对超软材料进行大变形测试显得比较困难。设计并建造了长15 m的双子弹电磁驱动长分离式霍普金森... 详细信息

生物软材料大多是高含水率的超软材料，其力学性能在宽应变率范围内随着应变率的提高而非线性增强。然而由于实验条件的限制，在中应变率下对超软材料进行大变形测试显得比较困难。设计并建造了长15 m的双子弹电磁驱动长分离式霍普金森压杆（long split Hopkinson pressure bar, LSHPB）系统，可用于超软材料的大变形中应变率测试。使用该LSHPB系统和高速SHPB系统分别对硅橡胶进行了测试，比较两者的实验结果，验证了系统的可靠性。应用LSHPB系统测量了聚乙烯醇（polyvinyl alcohols, PVA）水凝胶在中应变率下的力学性能，并且结合已有的低和高应变率的数据分析，说明了中应变率动态性能测试的必要性。

关键词：中应变率测试 LSHPB系统 PVA水凝胶动态力学行为