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High Voltage 2024年第5期9卷 1136-1148页

作者： yongming xu Ziyi xu Congrui Ren Yaodong Wang School of Electrical and Information Engineering Changzhou Institute of TechnologyChangzhouChina School of Electrical and Electronic Engineering Harbin University of Science and TechnologyHarbinChina Department of Engineering Durham UniversityDurhamUK

Due to the complex structure and large size of large-capacity oil-immersed power transformers,it is difficult to predict the winding temperature distribution directly by numerical analysis.A 180 MVA,220 kV oil-immersed self-cooling power transformer is used as the research *** authors decouple the internal fluid domain of the power transformer into four regions:high voltage windings,medium voltage windings,low voltage windings,and radiators through fluid networks and establish the 3D fluidtemperature field numerical analysis model of the four regions,*** results of the fluid network model are used as the inlet boundary conditions for the 3D fluidtemperature numerical analysis *** turn,the fluid resistance of the fluid network model is corrected according to the results of the 3D fluid-temperature field numerical analysis *** prediction of the temperature distribution of windings is realised by the coupling calculation between the fluid network model and the 3D fluid-temperature field numerical analysis *** on this,the effect of the loading method of the heat source is also investigated using the proposed *** hotspot temperatures of the high-voltage,medium-voltage,and low-voltage windings are 89.43,86.33,and 80.96°C,***,an experimental platform is built to verify the *** maximum relative error between calculated and measured values is 4.42%,which meets the engineering accuracy requirement.

关键词： winding network distribution

A wavelet packet based block-partitioning image coding algorithm with rate-distortion optimization

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Science in China(Series F) 2008年第8期51卷 1039-1054页

作者： YANG yongming xu Chao State Key Laboratory of Machine Perception Peking University Beijing 100871 China

As an elegant generalization of wavelet transform, wavelet packet （WP） provides an effective representation tool for adaptive waveform analysis. Recent work shows that image-coding methods based on WP decomposition can achieve significant gain over those based on a usual wavelet transform. However, most of the work adopts a tree-structured quantization scheme, which is a successful technique for wavelet image coding, but not appropriate for WP subbands. This paper presents an image-coding algorithm based on a rate-distortion optimized wavelet packet decomposition and on an intraband block-partitioning scheme. By encoding each WP subband separately with the block-partitioning algorithm and the JPEG2000 context modeling, the proposed algorithm naturally avoids the difficulty in defining parent-offspring relationships for the WP coefficients, which has to be faced when adopting the tree-structured quanUzation scheme. The experimental results show that the proposed algorithm significantly outperforms SPIHT and JPEG2000 schemes and also surpasses state-of-the-art WP image coding algorithms, in terms of both PSNR and visual quality.

关键词： basis selection bitplane coding context modeling set partition wavelet packet (WP)

An Observational Study on the Local Climate Effect of the Shangyi Wind Farm in Hebei Province

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Advances in Atmospheric Sciences 2021年第11期38卷 1905-1919页

作者： Yonghong LIU Bing DANG yongming xu Fuzhong WENG State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Beijing Municipal Climate Center Beijing 100089China School of Remote Sensing and Geomatics Engineering Nanjing University of Information Science and TechnologyNanjing 21004China

Zhangjiakou is an important wind power base in Hebei Province,*** impact of its wind farms on the local climate is *** on long-term meteorological data from 1981 to 2018,we investigated the effects of the Shangyi Wind Farm(SWF)in Zhangjiakou on air temperature,wind speed,relative humidity,and precipitation using the anomaly or ratio method between the impacted weather station and the non-impacted background weather *** influence of the SWF on land surface temperature(LST)and evapotranspiration(ET)using MODIS satellite data from 2003 to 2018 was also *** results showed that the SWF had an atmospheric warming effect at night especially in summer and autumn(up to 0.95℃).The daytime air temperature changes were marginal,and their signs were varying depending on the *** annual mean wind speed decreased by 6%,mainly noted in spring and winter(up to 14%).The precipitation and relative humidity were not affected by the *** was no increase in LST in the SWF perhaps due to the increased vegetation coverage unrelated to the wind farms,which canceled out the wind farm-induced land surface warming and also resulted in an increase in *** results showed that the impact of wind farms on the local climate was significant,while their impact on the regional climate was slight.

关键词： wind farms local climate effect air temperature wind speed land surface temperature evapotranspiration

Spatial Distribution of High-temperature Risk with a Return Period of Different Years in the Yangtze River Delta Urban Agglomeration

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Chinese Geographical Science 2022年第6期32卷 963-978页

作者： ZHANG Guixin WANG Shisheng ZHU Shanyou xu yongming School of Geographical Sciences Nanjing University of Information Science&TechnologyNanjing 210044China Academy of Environmental Planning&Design CO. LTD.Nanjing UniversityNanjing 210093China School of Remote Sensing and Geomatics Engineering Nanjing University of Information Science&TechnologyNanjing 210044China

Against the background of global warming,research on the spatial distribution of high-temperature risk is of great significance to effectively prevent the adverse effects of high *** using air temperature data from 1951 to 2018 measured by meteorological stations located in the Yangtze River Delta urban agglomeration,the daily maximum air temperature distribution is interpolated at a resolution of 1 km based on the local thin disk smooth spline function;the high-temperature threshold for return periods of 5,10,20 and 30 yr are then calculated by using the generalized extreme value *** yearly average high-temperature intensity and high-temperature days are finally calculated as high-temperature danger *** statistical data and remotely sensed image data in 2018 are used as the background data to calculate the spatial distribution of high-temperature vulnerability factors and prevention capacity factors,which are then used to compute the high-temperature risk index during different recurrence periods in the Yangtze River Delta urban *** results show that the spatial distribution features of high-temperature risk in different return periods are *** high-temperature risk index gradually increases from northeast to southwest and from east coast to inland,which has obvious latitude variation characteristics and a relationship with the comprehensive influence of the underlying surface and urban *** terms of time variation,the high-temperature risk index and its spatial distribution difference gradually decreases with increasing return *** different cities,the high-temperature risk in the central area of the city is generally higher than that in the surrounding suburban ***,Hangzhou of Zhejiang Province and xuancheng of Anhui Province are the top three cities with high-temperature risk in the study area.

关键词： high-temperature risk generalized extreme value method recurrence period remote sensing spatialization

Catalytic Amidation of 5-Hydroxymethylfurfural to 2,5-Furandicarboxamide over Alkali Manganese Oxides

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Chinese Journal of Chemistry 2017年第6期35卷 984-990页

作者： Xiaofang Li Xiuquan Jia Jiping Ma yongming xu Yizheng Huang Jie xu Dalian National Laboratory for Clean Energy State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian Liaoning 116023 China University of Chinese Academy of Sciences Beijing 100049 China

2,5-Furandicarboxamide was firstly synthesized in yield of 85% via catalytic oxidative amidation of 5-hydroxy- methylfurfural with aqueous NH3 over alkali manganese oxides of a-MnO2/NaxMnO〉 The intermediates of 5-hydroxymethyl-furonitrile, 2,5-dicyanofuran, and 5-cyano-2-furancarboxamide were verified and their reactivities were further examined. The kinetic analysis results showed that the transformation of intermediate product of 5-cyano-2-furancarboxamide to 2,5-furan-dicarboxamide is a slower step, which is closely relative to the reaction temperature and basicity of catalyst.

关键词： catalysis alkali manganese oxides 5-hydroxymethylfurfural ammoxidation 2,5-furandicarboxamide

Estimation of Terrestrial Net Primary Productivity in China from Fengyun-3D Satellite Data

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Journal of Meteorological Research 2022年第3期36卷 401-416页

作者： Yonghong LIU Xiuzhen HAN Fuzhong WENG yongming xu Yeping ZHANG Shihao TANG Earth System Modeling and Prediction Center China Meteorological AdministrationBeijing 100081 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081 National Satellite Meteorological Center China Meteorological AdministrationBeijing 100081 School of Remote Sensing and Geomatics Engineering Nanjing University of Information Science&TechnologyNanjing 210044

Currently,the satellite data used to estimate terrestrial net primary productivity(NPP)in China are predominantly from foreign satellites,and very few studies have based their estimates on data from China’s Fengyun ***,despite their importance,the influence of land cover types and the normalized difference vegetation index(NDVI)on NPP estimation has not been *** study employs the Carnegie–Ames–Stanford approach(CASA)model to compute the fraction of absorbed photosynthetically active radiation and the maximum light use efficiency suitable for the main vegetation types in China in accordance with the finer resolution observation and monitoring-global land cover(FROM-GLC)classification ***,the NPP is estimated from the Fengyun-3D(FY-3D)data and compared with the Moderate Resolution Imaging Spectroradiometer(MODIS)NPP *** FY-3D NPP is also validated with existing research results and historical field-measured NPP *** addition,the effects of land cover types and the NDVI on NPP estimation are *** results show that the CASA model and the FY-3D satellite data estimate an average NPP of 441.2 g C m^(−2) yr^(−1) in 2019 for China’s terrestrial vegetation,while the total NPP is 3.19 Pg C yr^(−1).Compared with the MODIS NPP,the FY-3D NPP is overestimated in areas of low vegetation productivity and is underestimated in high-productivity *** discrepancies are largely due to the differences between the FY-3D NDVI and MODIS *** with historical field-measured data,the FY-3D NPP estimation results outperformed the MODIS NPP results,although the deviation between the FY-3D NPP estimate and the in-situ measurement was large and may exceed 20%at the pixel *** land cover types and the NDVI significantly affected the spatial distribution of NPP and accounted for NPP deviations of 17.0%and 18.1%,***,the total deviation resulting from the two factors reached 29.5%.These results show that

关键词： net primary productivity(NPP) Carnegie-Ames-Stanford approach(CASA)model maximum light use efficiency Fengyun-3D(FY-3D) finer resolution observation and monitoring-global land cover(FROM-GLC)land cover types Moderate Resolution Imaging Spectroradiometer(MODIS)

整合DMSP/OLS和NPP/VIIRS夜间灯光遥感数据的长江三角洲城市格局时空演化研究

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地球信息科学学报 2021年第5期23卷 837-849页

作者：许正森徐永明南京信息工程大学遥感与测绘工程学院南京210044

本文基于1992—2012年DMSP/OLS和2012—2018年NPP/VIIRS夜间灯光遥感数据,对长江三角洲城市群时空演化格局进行监测。考虑到不同卫星夜间灯光遥感数据之间的不一致性以及城市核心区亮度过饱和问题,对DMSP/OLS和NPP/VIIRS数据进行连续性... 详细信息

本文基于1992—2012年DMSP/OLS和2012—2018年NPP/VIIRS夜间灯光遥感数据,对长江三角洲城市群时空演化格局进行监测。考虑到不同卫星夜间灯光遥感数据之间的不一致性以及城市核心区亮度过饱和问题,对DMSP/OLS和NPP/VIIRS数据进行连续性校正、去饱和处理和一致性校正,构建长江三角洲区域1992—2018年长时间序列多源夜间灯光遥感数据集。利用二分法基于该数据逐年提取长江三角洲城市群各城市建成区空间分布,计算加权标准差椭圆和Zipf系数进行重心变化和方向性分布变化、规模体系变化等监测。结果表明:(1)本研究采用的连续性校正、去饱和处理和一致性校正方法能够构建稳定的长时间序列多源夜间灯光遥感数据集;(2)基于二分法提取的建成区面积平均绝对误差为6.85 km^(2),平均相对误差为8.10%;(3)长三角城市群重心较为稳定,始终在苏州市境内的太湖沿岸附近,呈现出向东南方向移动的趋势城市群呈西北—东南方向分布,且分布方向有向南北方向转动的趋势,标准差椭圆的扁率持续减小,表明城市群的方向性分布减弱;(4)Zipf系数始终在1附近且呈缓慢降低的趋势,城市规模分布较为均衡。

关键词： DMSP/OLS NPP/VIIRS 夜间灯光长江三角洲城市群时空格局演变校正方法 VANUI

Impacts of the Urban Spatial Landscape in Beijing on Surface and Canopy Urban Heat Islands

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Journal of Meteorological Research 2022年第6期36卷 882-899页

作者： Yonghong LIU yongming xu Yeping ZHANG Xiuzhen HAN Fuzhong WENG Chunyi xuAN Wenjun SHU CMA Earth System Modeling and Prediction Centre China Meteorological Administration(CMA)Beijing 100081 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081 School of Remote Sensing and Geomatics Engineering Nanjing University of Information Science&TechnologyNanjing 210044 National Satellite Meteorological Centre China Meteorological AdministrationBeijing 100081 Beijing Municipal ClimateCentre Beijing Meteorological ServiceBeijing 100089

How does the urban spatial landscape(USL)pattern affect the land surface urban heat islands(SUHIs)and canopy urban heat islands(CUHIs)?Based on satellite and meteorological observations,this case study compares the impacts of the USL pattern on SUHI and CUHI in the central urban area(CUA)of Beijing using the satellite land-surface-temperature product and hourly temperature data from automatic meteorological stations from 2009 to *** USL metrics—building height(BH),building density(BD),standard deviation of building height(BSD),floor area ratio(FAR),frontal area index(FAI),roughness length(RL),sky view factor(SVF),urban fractal dimension(FD),vegetation coverage(VC),impervious coverage(IC),and albedo(AB)—with a 500-m spatial resolution in the CUA are extracted for comparative *** results show that SUHI is higher than CUHI at night,and SUHI is only consistent with CUHI at spatial-temporal scales at night,particularly in ***,all 11 metrics are strongly correlated with both the SUHI and CUHI at night,with stronger correlation between most metrics and ***,AB,and SVF have the greatest impact on both the SUHI and *** SUHI and CUHI values tend to appear in areas with BD≥0.26,VC≤0.09,AB≤0.09,and SVF≤*** summer,most metrics have a greater impact on the SUHI than CUHI;the opposite is observed in *** variation is affected primarily by VC in summer and by VC and AB in winter,which is different for the CUHI *** collective contribution of all 11metrics to SUHI spatial variation in summer(61.8%)is higher than that to CUHI;however,the opposite holds in winter and for the entire year,where the cumulative contribution of the factors accounts for 66.6%and 49.6%,respectively,of the SUHI variation.

关键词： surface urban heat island canopy urban heat island vegetation coverage albedo sky view factor building density Beijing

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酱香白酒堆积工艺糟醅置换技术研究

酿酒科技 2025年第1期 80-85页

作者：邓杰邓磊邓皖玉陈波李恒毅许永明曾鹏胡登权谢见飞四川郎酒股份有限公司四川古蔺646523 四川省酱香型白酒生态酿造工程技术研究中心四川古蔺646523

为探索新老车间糖化堆置换前后糟醅质量和原酒理化的差异,采取糖化堆糟醅置换接种方法,将老车间糖化堆糟醅中驯化成熟的菌种移植至新建车间,为持续驯化新建酿酒车间酿酒微生态环境,加快品质提升做铺垫,逐步提升新产区原酒质量。综合对... 详细信息

为探索新老车间糖化堆置换前后糟醅质量和原酒理化的差异,采取糖化堆糟醅置换接种方法,将老车间糖化堆糟醅中驯化成熟的菌种移植至新建车间,为持续驯化新建酿酒车间酿酒微生态环境,加快品质提升做铺垫,逐步提升新产区原酒质量。综合对窖池内微生物分析、风味分析、置换车间原酒尝评,结果表明,微生物含量较常规生产间有提升,新车间通过置换老车间糖化堆糟醅,提高了微生物富集量。本研究可为缩小新老车间质量差异及提升整体原酒品质提供基础数据和探索方向。

关键词：糖化堆糟醅置换微生物原酒尝评酿酒环境

中国古典文学研究的几种可视化途径——以汤显祖研究为例

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浙江大学学报（人文社会科学版） 2018年第2期48卷 164-174页

作者：徐永明浙江大学人文学院浙江杭州310028

当代西方教学和科研中常用的可视化工具主要有ArcGIS、QGIS、CHGIS、CartoDB、Worldmap、CBDB、GEPHI等数据库和软件。其中"中国历史地理信息系统"和"中国历代人物传记数据库"是由哈佛大学包弼德教授主持的项目,与中国的文史研究直接相... 详细信息

当代西方教学和科研中常用的可视化工具主要有ArcGIS、QGIS、CHGIS、CartoDB、Worldmap、CBDB、GEPHI等数据库和软件。其中"中国历史地理信息系统"和"中国历代人物传记数据库"是由哈佛大学包弼德教授主持的项目,与中国的文史研究直接相关。利用上述数据库和软件,以汤显祖为例,可展示汤显祖行迹和活动地点、社会关系地理分布、社会关系点线表达等多种可视化效果图,给人以直观明了、耳目一新之感。这些数据库和可视化呈现方法对中国古典文学的研究和教学将起到极好的辅助作用。

关键词：中国古典文学地理信息汤显祖可视化哈佛大学 CBDB CHGIS