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南水北调东线工程典型供排闸站施工导流分析研究

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江苏水利 2024年第3期 33-36页

作者：侯钧宇陈栋王凯杨晨霞严春华淮安市水利工程建设管理服务中心江苏淮安223001 江苏省水利勘测设计研究院有限公司江苏扬州225100

南水北调东线工程南起扬州长江,经13个梯级提水入东平湖后,穿黄北送等,线路总长1466.5 km。鉴于南水北调输水干线上水工建筑物的功能多样,加固改造时供排水导流工况复杂,选取输水干线典型闸站即沙集闸站,分功能、分时段、分规模、分方... 详细信息

南水北调东线工程南起扬州长江,经13个梯级提水入东平湖后,穿黄北送等,线路总长1466.5 km。鉴于南水北调输水干线上水工建筑物的功能多样,加固改造时供排水导流工况复杂,选取输水干线典型闸站即沙集闸站,分功能、分时段、分规模、分方案地进行导流,充分保障施工期工程原供排水充分效益发挥。

关键词：南水北调东线工程闸站泵站施工导流供水排水

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信号处理技术与残差分析联动的异常径流量判定方法

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吉林水利 2024年第4期 37-41页

作者：姜中清张玥周伊王宇露严春华江苏省水利勘测设计研究院有限公司江苏扬州225127

对异常径流量的判定是保证流域安全的重要手段。针对单一判定法可能存在的误判,本文提出了信号处理技术与残差分析联动判定法。该方法从两种不同角度分析异常径流信息,首先以经验模态分解法(EMD)获得包含异常信息的高频分量,以此为基准... 详细信息

对异常径流量的判定是保证流域安全的重要手段。针对单一判定法可能存在的误判,本文提出了信号处理技术与残差分析联动判定法。该方法从两种不同角度分析异常径流信息,首先以经验模态分解法(EMD)获得包含异常信息的高频分量,以此为基准得到异常阈值并识别相应异常值;然后以长短期记忆网络(LSTM)构建时序模型,得到包含异常信息的径流残差,进而确定异常阈值并判定相应异常值;最后融合两种方法的异常径流量判定结果。研究表明,提出的方法能够从不同角度挖掘异常径流信息,相互补充,可准确识别径流数据中不同类型的异常信息。

关键词：径流量异常判定残差分析高频径流量

近红外光谱法结合偏最小二乘法预测生物柴油中甲醇的含量

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理化检验（化学分册） 2024年第6期60卷 606-611页

作者：张卓昆闫春华岳承恩安端阳刘向前王梦迪张天龙李华西安石油大学化学化工学院西安710065 西北大学化学与材料科学学院西安710127

生物柴油中甲醇的定量分析对其品质监控具有重要科学意义与实用价值,因此进行了题示研究。制作44个含不同体积分数甲醇的生物柴油样品,采集了相应的近红外光谱。采用Savitzky-Golay平滑滤波(SG)和标准正态变换(SNV)相结合的方法对原始... 详细信息

生物柴油中甲醇的定量分析对其品质监控具有重要科学意义与实用价值,因此进行了题示研究。制作44个含不同体积分数甲醇的生物柴油样品,采集了相应的近红外光谱。采用Savitzky-Golay平滑滤波(SG)和标准正态变换(SNV)相结合的方法对原始光谱进行预处理,并采用协同区间偏最小二乘法(SIPLS)提取特征变量,确定在6270~6640 cm^(−1)和10900~11240 cm^(−1)波段内采用偏最小二乘法(PLS)建模。结果显示,所建SG-SNV-SIPLS-PLS模型的留一交叉验证决定系数R2 cv为0.9994,均方根误差RMSECV为0.0488,预测集决定系数R_(p)^(2)为0.9996,均方根误差RMSEP为0.0563,变量数为207,优于PLS模型以及单变量线性回归模型的。

关键词：生物柴油甲醇定量预测近红外光谱法偏最小二乘法

A novel strategy for quantitative analysis of soil pH via laser-induced breakdown spectroscopy coupled with random forest

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Plasma Science and Technology 2020年第7期22卷 21-27页

作者： Mingjing ZHAO chunhua yan Yaozhou FENG Jia XUE Hongsheng TANG Tianlong ZHANG Hua LI Key Laboratory of Synthetic and Natural Functional Molecular Chemistry of Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'an 710069People's Republic of China College of Chemistry and Chemical Engineering Xi'an Shiyou UniversityXi'an 710065People's Republic of China

pH is one of the significant properties of soil,and is closely related to the decomposition of soil organic matter,anion-cation balance,growth of plants and many other soil *** the present work,laser-induced breakdown spectroscopy(LIBS) technique coupled with random forest(RF) was proposed to quantify the pH of ***,LIBS spectra of soil was collected,and some common elements in soil were identified based on the National Institute of Science and Technology ***,in order to obtain a better predictive result,the influence of different input variables(full spectrum,different spectral ranges,the intensity of characteristic bands and characteristic lines) on the predictive performance of RF calibration model was explored with the evaluation indicators of root mean square error(RMSE) and coefficient of determination(R2),the characteristic bands of four elements(AI,Ca,Mg and Si) were determined as the optimal input ***,the predictive performance of RF calibration model was compared with partial least squares calibration model with the optimal input variables and model parameters,and RF calibration model showed a better predictive performance,and the four evaluation indicators of R_p^2,RMSEP,mean absolute error and mean relative error were 0.9687,0.1285,0.1114 and 0.0136,*** indicates that LIBS technique coupled with RF algorithm is an effective method for pH determination of soil.

关键词： laser-induced breakdown spectroscopy(LIBS) random forest soil pH quantitative analysis

基于时间自动机的列控系统等级转换建模与验证

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科学技术创新 2024年第6期 21-24页

作者：董家希刘珂帆鄢春花杜利芳周家宇成都工业学院汽车与交通学院四川成都

随着列控系统的发展,我国现有铁路线路主要应用有CTCS-3级和CTCS-2级两种列控系统。等级转换是在列车运行控制过程中起到重要作用,其功能的正确性直接关系到列控系统的安全性。本文采用时间自动机建模方法,依据CTCS-3级列控系统总体基... 详细信息

随着列控系统的发展,我国现有铁路线路主要应用有CTCS-3级和CTCS-2级两种列控系统。等级转换是在列车运行控制过程中起到重要作用,其功能的正确性直接关系到列控系统的安全性。本文采用时间自动机建模方法,依据CTCS-3级列控系统总体基础方案的需求规范,对等级转换场景进行了功能性及实时性的需求分析,描述CTCS-3级和CTCS-2级列控系统转换过程中的功能特性和时间约束,对等级转换场景进行建模仿真,并通过形式化验证的方式检验模型的正确性。

关键词：列控系统等级转换 UPPAAL建模时间自动机

Synthesis and Characterization of Tetravalent Cerium Complexes with p-Tert-butylcalix[n]arenes (n=4, 6, 8)

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Journal of Rare Earths 2002年第1期20卷 41-46页

作者：张亚文严纯华增田嘉孝 State Key Laboratory of Rare Earth Materials Chemistry and Applications & PKU-HKU Joint Laboratory on Rare Earth Materials and Bioinorganic Chemistry Peking University Beijing 100871 China Diuision of Materials Science The Graduate School of Science and Technology Kobe UniuersityRokkodaiNada-kuKobe 657Japan

Three Ce 4+ complexes Ce(p tert butylcalixarene)·(dmf) 4·H 2O (complex A), Ce(p tert butylcalixarene) 2·(dmf) 10 (complex B) and Ce(p tert butylcalixarene)·(dmf) 4 (complex C) were prepared from N,N dimethylforamide (dmf) solution of Ce(NO 3) 3. Their thermal stability, optical properties and coordination features were investigated with thermogravimetric and differential thermal analysis, ultraviolet and visible spectrophotometer, fluorescence spectrophotometer, infrared spectroscopy, and 1H NMR spectrometer. In the solvents of C 6H 6, 1,2 dichloroethane and dmf, complexes A and B can exhibit a ligand to metal charge transfer transition lying in ca. 20000 cm -1 in the electronic spectra. Complex A displays a dimeric structure in C 6D 6 solution. Ce 4+ ions in the complexes are coordinated by phenolic groups of the ligands, oxygen atoms of dmf molecules, and / or OH - ions.

关键词： rare earths tetravalent cerium complex p t butyl calixarene spectroscopic characterization

考虑时间效应的VMD-BiLSTM径流量预测模型研究

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江苏水利 2024年第2期 5-10页

作者：严春华侯钧宇梅杰蒋肇冰姜中清徐乔婷江苏省水利勘测设计研究院有限公司江苏扬州225100 淮安市水利工程建设管理服务中心江苏淮安223001

首先采用VMD对非稳态的径流量进行变量分解,提取了径流量的多尺度特征信息;然后采用BiLSTM算法通过反向学习实现了对径流量时间效应的信息捕捉和传递,并采用Dropout技术解决了BiLSTM模型在训练过程中存在过拟合的问题,从而构建了考虑时... 详细信息

首先采用VMD对非稳态的径流量进行变量分解,提取了径流量的多尺度特征信息;然后采用BiLSTM算法通过反向学习实现了对径流量时间效应的信息捕捉和传递,并采用Dropout技术解决了BiLSTM模型在训练过程中存在过拟合的问题,从而构建了考虑时间效应的径流量的预测模型。由工程案例可知,与其他常规模型相比,该模型的预测精度最高,可靠性较高,预测精度水平能够满足工程实际的应用。该模型为径流量的预测研究提供借鉴。

关键词： VMD BiLSTM 径流量预测时间效应

Shifting from homogeneous to heterogeneous surfaces in estimating terrestrial evapotranspiration: Review and perspectives

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Science China Earth Sciences 2022年第2期65卷 197-214页

作者： Yuanbo LIU Guoyu QIU Hongsheng ZHANG Yonghui yanG Yinsheng ZHANG Quan WANG Wenzhi ZHAO Li JIA Xibin JI Yujiu XIONG chunhua yan Ning MA Shumin HAN Yifan CUI Nanjing Institute of Geography and Limnology Chinese Academy of SciencesNanjing 210008China School of Environment and Energy Peking University Shenzhen Graduate SchoolShenzhen 518055China Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100081China Key Laboratory for Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050022China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China Faculty of Agriculture Shizuoka UniversityShizuoka 422-8529Japan Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China Key Laboratory of Ecohydrology of Inland River Basin Chinese Academy of SciencesLanzhou 730000China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China School of Civil Engineering Sun Yat-Sen UniversityGuangzhou 510275China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Terrestrial evapotranspiration(ET)is a crucial link between Earth’s water cycle and the surface energy *** measurement and estimation remain a major challenge in geophysical,biological,and environmental *** work,represented by Dalton and Penman,and the development of theories and experiments on turbulent exchange in the atmospheric boundary layer(ABL),laid the foundation for mainstream methodologies in ET *** the 1990s,eddy covariance(EC)systems and satellite remote sensing have been widely applied from cold to tropical and from arid to humid *** cover water surfaces,wetlands,forests,croplands,grasslands,barelands,and urban areas,offering an exceptional number of reports on diverse ET *** nocturnal ET,hysteresis between ET and environmental forces,turbulence intermittency,island effects on heterogeneous surfaces,and phase transition between underlying surfaces are examples of reported new phenomena,posing theoretical and practical challenges to mainstream ET ***,based on non-conventional theories,new methods have emerged,such as maximum entropy production and nonparametric ***,high-frequency on-site observation and aerospace remote sensing technology in combination form multi-scale observations across plant stomata,leaves,plants,canopies,landscapes,and *** promotes an insightful understanding of diverse ET processes and synthesizes the common mechanisms of the processes between and across spatial and temporal *** the recent achievements in conception,model,and technology serve as the basis for breaking through the known difficulties in ET *** expect that they will provide a rigorous,reliable scientific basis and experimental support to address theoretical arguments of global significance,such as the water-heat-carbon cycle,and solve practical needs of national importance,including agricultural irrigation and food security,precise manageme

关键词： Evapotranspiration Atmospheric boundary layer Heterogeneous surface Uncertainty

Minimum amount of extracting solvent of AB/BC countercurrent extraction separation using organic feed

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Journal of Rare Earths 2014年第5期32卷 439-444页

作者：程福祥吴声张玻刘艳王嵩龄廖春生严纯华 China Minmetals (Beijing) Research Institute of RE Co. Ltd Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications PKU-HKU Joint Lab on Rare Earth Materials and Bioinorganic Chemistry Peking University

For an AB/BC countercurrent extraction separation using organic feed, the conditions to have minimum amount of ex- tracting solvent （Smin） and minimum amount of scrubbing agent solution （Wmin） were discussed, and the formulae of both Sroin and Wmin were deduced. It was shown that only when the ratio of flowrate of central component B leaving aqueous outlet to that leaving organic outlet took a certain optimal value, the AB/BC separation could have Smin as well as Wmin, and this optimal ratio was decided by the separation factors between the three components but independent of feed composition. Smin was only relative to the separation factor of A/C pair but regardless of the separation factors of other pairs as well as feed composition, whereas Wmin was determined by the separation factors between the components together with feed composition. Meanwhile it was also found that the organic stream out of feed stage was same composition as the initial organic feed when the separation system was given by the two minimum amounts and its steady state was achieved. Finally the results above were used to design a LuYb/YbTm separation case and the stage-wise compositions of each component in both the organic and the aqueous phase at steady state were given by computer simulation.

关键词： rare earths countercurrent extraction hyperlink process 3-component separation