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Spectral data treatments for impervious endmember derivation and fraction mapping from Landsat ETM＋ imagery： a comparative analysis

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Frontiers of Earth Science 2015年第2期9卷 179-191页

作者： Wei WANG xinfeng yao Minhe JI Jiao ZHANG Key Laboratory of GIScience (Ministry of Education of China) East China Normal University Shanghai 200241 China Agricultural Information Institute of Science and Technology Shanghai Academy of Agricultural Sciences Shanghai 201403 China China East-West Cooperation Research Center East China Normal University Shanghai 200241 China

Various spectral data preprocessing approaches have been used to improve endmember extraction for urban landscape decomposition, yet little is known of their comparative adequacy for impervious surface mapping. This study tested four commonly used spectral data treatment strategies for endmember derivation, including original spectra, image fusion via principal component analysis, spectral normalization, and the minimum noise fraction （MNF） transformation. Land cover endmembers derived using each strategy were used to build a linear spectral mixture analysis （LSMA） model in order to unmix treated image pixels into fraction maps, and an urban imperviousness map was generated by combining the fraction maps representing imperviousness endmembers. A cross-map comparative analysis was then performed to rank the four data treatment types based on such common evaluation indices as the coefficient of determination （R2） and root mean square error （RMSE）. A Landsat 7 ETM~ multispectral image covering the metropolitan region of Shanghai, China was used as the primary dataset, and the model results were evaluated using high-resolution color- infrared aerial photographs of roughly the same time period. The test results indicated that, with the highest R2 （0.812） and the lowest RMSE （0.097） among all four preprocessing treatments, the endmembers in the form of MNF-transformed spectra produced the best model output for characterizing urban impervious surfaces. The outcome of this study may provide useful guidance for future impervious surface mapping using medium-resolution remote sensing data.

关键词： impervious surface estimation linear spectral

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Cloud-based typhoon-derived paddy rice flooding and lodging detection using multi-temporal Sentinel-1&2

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Frontiers of Earth Science 2019年第4期13卷 682-694页

作者： Wanben WU Wei WANG Michael E.Meadows xinfeng yao Wei PENG School of Geographic Sciences East China Normal UniversityShanghai 200241China Information Technology Services Office East China Normal UniversityShanghai 200241China Department of Environmental&Geographical Science University of Cape TownCape Town 7701South Africa Shanghai Academy of Agricultural Sciences Shanghai 201403China

Rice production in China’s coastal areas is frequently affected by typhoons,since the associated severe storms,with heavy rain and the strong winds,lead directly to the rice plants becoming flooded or ***-term flooding and lodging can cause a substantial reduction in rice yield or even destroy the harvest *** is therefore urgent to obtain accurate information about paddy rice flooding and lodging as soon as possible after the passing of the *** paper proposes a workflow in Google Earth Engine(GEE)for mapping the flooding and lodging area of paddy rice in Wenzhou City,Zhejiang,following super typhoon Maria(Typhoon No.8 in 2018).First,paddy rice in the study area was detected by multi-temporal Sentinel-1 backscatter data combined with Sentinel-2-derived Normalized Difference Vegetation Index(NDVI)using the Random Forests(RFs)*** classification accuracies were achieved,whereby rice detection accuracy was calculated at 95%(VH+NDVI-based)and 87%(VV+NDVI-bastd).Secondly,Change Detection(CD)based Rice Normalized Difference Flooded Index(RNDFI)and Rice Normalized Difference Lodged Index(RNDLI)were proposed to detect flooding and lodged paddy *** RNDFI and RNDLI were tested based on four different remote sensing data sets,including the Sentinel-1-derived VV and VH backscattering coefficient,Sentinel-2-derived NDVI and Enhanced Vegetation Index(EVI).Overall agreement regarding detected area between the each two different data sets was obtained,with values of 79%to 93%in flood detection and 64%to 88%in lodging *** resulting flooded and lodged paddy rice maps have potential to reinforce disaster emergency assessment systems and provide an important resource for disaster reduction and emergency departments.

关键词： typhoons paddy rice flooding lodging Sentinel-1 Sentinel-2 Google Earth Engine

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Comprehensive understanding on sources of high levels of fine particulate nitro-aromatic compounds at a coastal rural area in northern China

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Journal of Environmental Sciences 2024年第1期135卷 483-494页

作者： Yueru Jiang xinfeng Wang Min Li Yiheng Liang Zhiyi Liu Jing Chen Tianyi Guan Jiangshan Mu Yujiao Zhu He Meng Yang Zhou Lan yao Likun Xue Wenxing Wang Environment Research Institute Shandong UniversityQingdao 266237China Department of Environmental Systems Science Swiss Federal Institute of Technology ZurichZurich 8092Switzerland Department of Water Resources and Drinking Water Swiss Federal Institute of Aquatic Science and TechnologyDuebendorf 8600Switzerland Qingdao Eco-Environment Monitoring Center of Shandong Province Qingdao 266003China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghai 200234China

Nitro-aromatic compounds(NACs)are among the major components of brown carbon(BrC)in the atmosphere,causing negative impacts on regional climate,air quality,and ecological *** to the extensive origins,it is still a challenge to figure out the contributions and originating regions for different sources of atmospheric ***,field observations on fine particulate NACs were conducted at a coastal rural area in Qingdao,China in the winter of 2018 and *** mean total concentrations of fine particulate nitro-aromatic compounds were 125.0±89.5 and 27.7±21.1 ng/m^(3)in the winter of 2018 and 2019,*** the measured eleven NACs,nitrophenols and nitrocatechols were the most abundant *** characteristics and correlation analysis showed that humidity and anthropogenic primary emissions had significant influences on the NAC *** this study,two tracing methods of the improved spatial concentration weighted trajectory(SCWT)model and the receptor model of positive matrix factorization(PMF)were combined to comprehensively understand the origins of NACs in fine particles at coastal *** major sources were identified,including coal combustion,biomass burning,vehicle exhaust,and secondary ***,coal combustion was responsible for about half of the observed nitro-aromatic compounds,followed by biomass burning(~30%).The results by SCWT demonstrated that the coal combustion dominated NACs mainly originated from the Shandong peninsula and the areas to the north and southwest,while those dominated by biomass burning primarily came from local Qingdao and the areas to the west.

关键词： Nitro-aromatic compounds Fine particles Source apportionment Originating region Combustion activities

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TJCJ-1型机车架车机的检修方案

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机车车辆工艺 2020年第2期 59-60页

作者：姚新丰中国宝武集团八钢公司物流运输分公司新疆乌鲁木齐830022

介绍了TJCJ-1机车架车机在使用中存在的难点问题,从机车架车机底座与机身垂直度超限、架车机活动托架滚轮与滚轮轴及架车机升降丝杠上端定位轴套与丝杠轴在使用中易固死等方面分析了具体原因,并提出了相应的改进措施,在现场使用中取得... 详细信息

介绍了TJCJ-1机车架车机在使用中存在的难点问题,从机车架车机底座与机身垂直度超限、架车机活动托架滚轮与滚轮轴及架车机升降丝杠上端定位轴套与丝杠轴在使用中易固死等方面分析了具体原因,并提出了相应的改进措施,在现场使用中取得了良好效果.

关键词：机车架车机底座与机身垂直度超限固死检修

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GDF-15在2型糖尿病肾病中的表达水平及临床意义

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中国医师杂志 2017年第3期19卷 418-420页

作者：姚新丰解放军第九八医院内一科浙江省湖州313000

目的研究生长分化因子-15（GDF-15）在2型糖尿病肾病中的表达水平及临床意义。方法选择2012年1月至2013年1月2型糖尿病肾病（DN）患者68例（DN组）和同期的2型糖尿病患者66例（DM组）和正常无糖尿病家族史志愿者30例（NC组）进行研究，... 详细信息

目的研究生长分化因子-15（GDF-15）在2型糖尿病肾病中的表达水平及临床意义。方法选择2012年1月至2013年1月2型糖尿病肾病（DN）患者68例（DN组）和同期的2型糖尿病患者66例（DM组）和正常无糖尿病家族史志愿者30例（NC组）进行研究，检测血液常规和肾功能，利用酶联免疫吸附测定（ELISA）检测GDF-15水平，受试者工作特征曲线（ROC曲线）分析GDF-15水平的诊断意义。结果2型糖尿病肾病患者血液中GDF-15水平显著高于2型糖尿病患者和正常对照组（P〈0.05）。GDF-15水平与LDL、空腹胰岛素（INS）和eGFR呈负相关（P〈0.05），与TC、TG、HDL、FBG、HbA1c、hsCRP、SCR、BUN、24 h尿微量白蛋白（mAlb）、尿白蛋白排泄率（URER）呈正相关（P〈0.05），而与BMI、SBP、DBP无关（P〉0.05）。GDF-15水平可以用于诊断2型糖尿病肾病，达到最佳敏感度82.2%和特异度70.2%。结论GDF-15水平对2型糖尿病肾病的诊断和发病机制具有重要意义。

关键词：转化生长因子β/代谢糖尿病肾病/代谢

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基于遥感与模型耦合的冬小麦生长预测

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生态学报 2011年第4期31卷 1073-1084页

作者：黄彦朱艳王航姚鑫锋曹卫星 David B.Hannaway 田永超南京农业大学/江苏省信息农业高技术研究重点实验室江苏南京210095 俄勒冈州立大学农业科学学院作物与土壤科学系美国俄勒冈科瓦利斯973313002

遥感的空间性、实时性与作物生长模型的过程性、机理性优势互补,将两者有效耦合已成为提高作物生长监测预测能力的重要手段之一。提出了一种基于地空遥感信息与生长模型耦合的冬小麦预测方法,该方法基于初始化/参数化策略,以不同生育时... 详细信息

遥感的空间性、实时性与作物生长模型的过程性、机理性优势互补,将两者有效耦合已成为提高作物生长监测预测能力的重要手段之一。提出了一种基于地空遥感信息与生长模型耦合的冬小麦预测方法,该方法基于初始化/参数化策略,以不同生育时期的小麦叶面积指数(LAI)和叶片氮积累量(LNA)为信息融合点将地面光谱数据(ASD)及HJ-1 A/B CCD、Landsat-5 TM数据与冬小麦生长模型(WheatGrow)耦合,反演得到区域尺度生长模型运行时难以准确获取的部分管理措施参数(播种期、播种量和施氮量),在此基础上实现了对冬小麦生长的有效预测。实例分析结果表明,LNA较LAI对模型更敏感,以之作为耦合点的反演效果较好。另外,抽穗期是遥感信息与生长模型耦合的最佳时机,对播种期、播种量和施氮量反演的RMSE值分别达到5.32 d、14.81 kg/hm2、14.11 kg/hm2。生长模型与遥感耦合后的模拟结果很好地描述了冬小麦长势和生产力指标的时空分布状况,长势指标的模拟相对误差小于0.25,籽粒产量模拟的相对误差小于0.1。因此研究结果可为区域尺度冬小麦生长的监测预测提供重要理论依据。

关键词：遥感 WheatGrow模型模型参数初始化生长预测

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粉末冶金技术在溅射靶材制备中的研究现状

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热加工工艺 2024年第7期53卷 7-10,36页

作者：姚甜王新锋刘李旭向长淑西安赛隆金属材料有限责任公司陕西西安710000 金属多孔材料国家重点实验室陕西西安710000

磁控溅射靶材由于沉积速率快、镀膜均匀等优点,已成为各类薄膜材料的首选制备方法。同时薄膜材料的广泛应用使得靶材的需求量逐年增多。近年来,粉末冶金技术在溅射靶材制备中得到了广泛应用。本文对靶材制备中使用的粉末冶金技术进行总... 详细信息

磁控溅射靶材由于沉积速率快、镀膜均匀等优点,已成为各类薄膜材料的首选制备方法。同时薄膜材料的广泛应用使得靶材的需求量逐年增多。近年来,粉末冶金技术在溅射靶材制备中得到了广泛应用。本文对靶材制备中使用的粉末冶金技术进行总结和工艺分析,并阐述热压烧结、热等静压烧结、放电等离子烧结的研究现状,最后探讨靶材制备研究中存在的技术问题和发展趋势。

关键词：粉末冶金靶材热压烧结热等静压烧结放电等离子烧结

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Helical supramolecular nanorods via sequential meticulous tailoring of noncovalent interaction and light irradiation

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Science China Chemistry 2022年第9期65卷 1749-1757页

作者： Zhenghui Liu Yuan yao xinfeng Tao Jie Wei Shaoliang Lin Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

Polymers are widely recognized to entail random conformations in good solvent governed by the need for achieving the highest entropy to reach thermodynamic *** this context,it remains grand challenging to directly arrange them into ordered conformation as building blocks for further self-assembling into hierarchal ***,we report a simple yet viable strategy to progressively assemble rationally designed azobenzene-containing alternating copolymer(i.e.,poly(binaphthylspacer-azobenzene-alt-hexaethylene glycol),denoting P(BNPSAzo-alt-EG_(6))_(24))into helical supramolecular ***,P(BNPSAzo-alt-EG_(6))_(24) chains in good solvent are firstly self-assembled into helical single molecular micelles in good solvent via intramolecular π-π interaction between binaphthyl groups as well as between azobenzene ***,by simply introducing water into the solution that is allowed to dwell for a certain period of time,single molecular micelles are selfassembled into well-defined ***,these isotropic vesicles could be further transformed into anisotropic helical supramolecular nanorods with enhanced aggregate-induced emission(AIE)capability driven by repeated,light-triggered cistrans isomerization of azobenzene moieties with the retention of π-π interacted binaphthyl *** study highlights a facile route to yielding morphology-rich,functional assemblies from a single polymer via judiciously exploiting non-covalent interaction and light of different wavelength as highly effective trigger in a non-invasive manner for potential applications in controlled release and fluorescent labelling.

关键词： alternating polymer conformational organization assembly chirality transmission light response azobenzene

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Strange Attractors in the Resonance Interaction of Two-State Atoms with Single-Mode Laser Field

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Wuhan University Journal of Natural Sciences 1998年第1期3卷 32-34页

作者： Xue xinfeng Zhang Yuesheng yao Duanzheng Wuhan Univ Wuhan China

The resonance interaction of two-state atoms with single mode field is described theoretically by using the semi-classical theory and Jaynes-Cummings model. The nonlinear characteristics of this system are calculated by using FFT and Runge-Kutta methods. The chaotic strange attractors in this system are obtained from the numerical results.

关键词： strange attractor atoms interacting with laser field RWA

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两种代偿公式判断酸碱失衡的一致性研究

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中国现代医生 2010年第20期48卷 85-87页

作者：韦国强陈娟王印国罗小春姚新丰解放军第九八医院神经内科浙江湖州313000

目的比较Hamm等和周寿生等两组酸碱失衡预计代偿范围计算公式的差别。方法分别将1500份模拟及745份实测异常酸碱失衡数据,同时用两组公式判断其酸碱失衡类型,用Kappa检验两组公式的一致性。结果两组公式判断模拟200份(实测108份,下同)代... 详细信息

目的比较Hamm等和周寿生等两组酸碱失衡预计代偿范围计算公式的差别。方法分别将1500份模拟及745份实测异常酸碱失衡数据,同时用两组公式判断其酸碱失衡类型,用Kappa检验两组公式的一致性。结果两组公式判断模拟200份(实测108份,下同)代酸,一致率为75.00%(70.37%),Kappa值为0.49(0.41),P均<0.01。判断模拟500份(实测132份)代碱,一致率为56.80%(59.09%),Kappa值为0.14(0.18),P<0.01(<0.05)。判断模拟200份(实测81份)急性呼酸,一致率为58.50%(65.43%),Kappa值为0.26(0.31),P均<0.01。判断模拟200份(实测168份)急性呼碱,一致率为53.00%(54.76%),Kappa值为0.20(0.24),P均<0.01。判断模拟200份(实测119份)慢性呼酸,一致率为84.50%(67.23%),Kappa值为0.45(0.41),P均<0.01。判断模拟200份(实测137份)慢性呼碱,一致率为73.00%(66.61%),Kappa值为0.49(0.43),P均<0.01。结论用Hamm等和周寿生等两组公式判断模拟及实测酸碱失衡类型均存在明显差别。

关键词：酸碱平衡紊乱预计代偿范围模拟数据

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