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A COUPLED MODEL OF HYDRODYNAMICS AND water QUALITY FOR YUQIAO RESERVOIR IN HAIHE RIVER BASIN

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Journal of Hydrodynamics 2008年第5期20卷 574-582页

作者： LIU Xiao-bo PENG Wen-qi HE Guo-jian LIU Jing-ling WANG Yu-chun school of Environment Beijing Normal University Beijing 100875 China Department of water Environment China Institute of Water Resources and Hydropower Research Beijing100038 China Department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering TsinghuaUniversity Beijing 100084 China

In order to simulate the characteristics of hydrodynamic field and mass transport processes in the Yuqiao Reservoir （YQR）, a 2-D coupled model of hydrodynamics and water quality was developed, and the water-quality related state variables in this model included CODMn, TN and TP. The hydrodynamic model was driven by employing observed winds and daily measured flow data to simulate the seasonal water cycle of the reservoir. The simulation of the mass transport and transformation processes of CODMn, TN and TP was based on the unsteady diffusion equations, driven by observed meteorological forcing and external loadings, with the fluxes form the bottom of reservoir and the plant photosynthesis and respiration as internal sources and sinks. A finite volume method and Alternating Direction Implicit （ADI） scheme were used to solve these equations. The model was calibrated and verified by using the data observed from YQR in two different years. The results showed that in YQR, the wind-driven current was an important style of lake current, while the concentration of water quality item was decreasing from east to west because of the external pollutant loadings. There was a good agreement between the simulated and measured values, with the minimal calculation error percent of 0.1% and 2.6% and the mean error percent of 44.0% and 51.2% for TN and TP separately. The simulation also showed that, in YQR, the convection was the main process in estuaries of inflow river, and diffusion and biochemical processes dominate in center of reservoir. So it was necessary to build a pre-pond to reduce the external loadings into the reservoir.

关键词： model simulation Yuqiao Reservoir (YQR) wind driven current water quality

Effect of Aqueous Colloids on Arsenic Geochemistry:Evidences from Ultrafiltration of High Arsenic Groundwater in the Hetao Basin,Inner Mongolia

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地学前缘 2009年第S1期16卷 20-21页

作者： Bo Zhang,Huaming Guo school of water resources & Environment,china university of Geosciences(Beijing),Beijing 100083,china.

Groundwater colloidal particles are believed to affect element geochemical behavior in groundwaters, which would mobilize trace element in the groundwater *** of As geochemisttry as impacted by colloids was carried out by using ultrafiltration technology in the Hetao basin,Inner *** groundwater sampling points have been chosen,including five with high As concentration (>100μg/L) and one with low As concentra-

关键词： As mobilization hydrogeochemistry particle dissolved organic carbon inorganic colloid

系统优化的GM(1,1)模型在大坝位移预测中的应用

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水电能源科学 2011年第4期29卷 76-77,126页

作者：郑雪琴秦栋河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098 河海大学水利水电学院江苏南京210098

针对传统灰色GM(1,1)模型的缺陷,以陈村大坝为例,根据最小二乘原理提出了以GM(1,1)的一次累加生成建模序列所有分量的拟合误差平方和最小为约束条件,求得新灰色GM(1,1)预测模型的最优初始值,改进了原GM(1,1)模型的背景值及灰度值,并与传... 详细信息

针对传统灰色GM(1,1)模型的缺陷,以陈村大坝为例,根据最小二乘原理提出了以GM(1,1)的一次累加生成建模序列所有分量的拟合误差平方和最小为约束条件,求得新灰色GM(1,1)预测模型的最优初始值,改进了原GM(1,1)模型的背景值及灰度值,并与传统GM(1,1)模型做了比较。数值仿真结果表明,新模型精度较高,预测效果较理想。

关键词：灰色系统传统灰色GM(1,1)模型优化GM(1,1)模型大坝位移预测

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坞首大体积混凝土温控仿真分析

水电能源科学 2011年第4期29卷 105-107页

作者：李小奇吴丹张伟河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098 河海大学水利水电学院江苏南京210098

采用1~7 d不同浇筑方案,基于热传导方程和应力增量方程,采用HyperMesh建立坞首模型,利用ABAQUS分析计算了浇筑0~90 d的坞首底板和台墩温度场与应力,并做出了温度场和应力曲线寻找最易开裂区域和时间,给出解决办法并确定了最优方案。

关键词：大体积混凝土有限元温度场温度应力仿真分析

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基于健康河流理念的肇庆市独河修复方案

水电能源科学 2010年第3期28卷 24-26页

作者：沈荣张治倩河海大学水文水资源学院江苏南京210098

针对河流屡遭污染破坏的现状,阐述了恢复河流健康生命的重要性,提出了河流健康的两个特征,运用健康河流理念研究了恢复肇庆市独河河流健康的整治方案,即通过结构调整、生态功能修复、生态护坡和滨水景观建设实现独河河流系统结构和功能... 详细信息

针对河流屡遭污染破坏的现状,阐述了恢复河流健康生命的重要性,提出了河流健康的两个特征,运用健康河流理念研究了恢复肇庆市独河河流健康的整治方案,即通过结构调整、生态功能修复、生态护坡和滨水景观建设实现独河河流系统结构和功能的完善,达到增强肇庆高新区社会经济活力的目标。

关键词：健康河流河流结构服务功能修复治理独河

Hydrological Frequency Analysis Based on Robust Statistical Theory

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Hydrological Frequency Analysis Based on Robust Statistical ...

2009中国控制与决策会议

作者： LIANG Zhongmin,SHI Ye,TANG Chunyi State Key Laboratory of hydrology-water resources and Hydraulic Engineering,hohai university,nanjing,210098

＜正＞In hydrological frequency analysis,the basic assumption that hydrological extremes are identically distributed from a given probability distribution with unknown parameters,is somewhat *** is more likely to recognize that data collected from observation are from a‘contaminated’*** this paper,a new robust statistical method was designed to provide quantile estimates by data from the ’contaminated’ probability *** method is constructed by combining Huber’s M-Estimator（M-E） and Minimum Distance Estimator（MD-E）.It has been shown that M-E is capable of obtaining a robust estimation of the location parameter of a distribution,and MD-E is able to achieve the robust estimations of its scale and shape *** properties of the proposed method have been studied based on Monte-Carlo experiment to the Person type three distribution（P-3）.Results show that the method presented is robust and has advantages in preserving good statistical properties.

关键词： Hydrological frequency analysis Robust statistics Huber’s M-Estimator Minimum Distance Estimator Monte-Carlo experiment Person type three distribution

来源： cnki会议评论

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宜昌站洪水流量事件变化规律研究

水电能源科学 2010年第1期28卷 41-43,46页

作者：张楠夏自强江红河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水文水资源学院江苏南京210098 华北水利水电学院河南郑州450011

以宜昌水文站1950-2006年洪水极值事件为例，采用Morlet小波函数分析了1～60d洪水流量系列年际变化规律，揭示了洪水极值事件变化的多时间尺度的复杂结构，并根据主周期预测了未来变化。结果表明，该方法方便、有效，为研究水库调度、... 详细信息

以宜昌水文站1950-2006年洪水极值事件为例，采用Morlet小波函数分析了1～60d洪水流量系列年际变化规律，揭示了洪水极值事件变化的多时间尺度的复杂结构，并根据主周期预测了未来变化。结果表明，该方法方便、有效，为研究水库调度、防洪规划、洪水极值流量变化、河流生态系统保护和修复提供了依据。

关键词：洪水流量事件变化小波分析极值尺度周期

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淮河流域可利用降水量特征及其影响因子分析

水电能源科学 2010年第3期28卷 4-5,38页

作者：宋颖玲葛朝霞曹琨薛梅河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水文水资源学院江苏南京210098 河海大学工程中心江苏南京210098

通过滑动平均和小波分析的方法分析了1951～2006年淮河流域可利用降水量的演变趋势和变化特征，采用相关分析及逐步回归法挑选了7个与淮河流域可利用降水量关系密切的大气环流因子，并分析了其对可利用降水量的影响。结果表明，近十几... 详细信息

通过滑动平均和小波分析的方法分析了1951～2006年淮河流域可利用降水量的演变趋势和变化特征，采用相关分析及逐步回归法挑选了7个与淮河流域可利用降水量关系密切的大气环流因子，并分析了其对可利用降水量的影响。结果表明，近十几年淮河流域的可利用降水量呈周期为2～3a的震荡；副高、极涡指数、欧亚纬向环流对淮河流域的可利用降水量影响较大。所得结论可为有关部门决策提供参考。

关键词：淮河可利用降水量小波分析相关分析逐步回归大气环流因子

Influence of the impounding process of the Three Gorges Reservoir up to water level 172.5m on water eutrophication in the Xiangxi Bay

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Science china(Technological Sciences) 2010年第4期53卷 1114-1125页

作者： YANG ZhengJian1,LIU DeFu1,JI DaoBin1,2 & XIAO ShangBin1,3 1 College of Civil & Hydroelectric Engineering,china Three Gorges university,Yichang 443002,china 2 school of water resources & Hydropower Engineering,Wuhan university,Wuhan 430072,china 3 Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,china College of Civil & Hydroelectric Engineering China Three Gorges University school of water resources & Hydropower Engineering Wuhan University

The water level of the Three Gorges Reservoir(TGR) rose to 172.5 m in two stages from September to November,*** hydrodynamic parameters and water quality parameters(*** velocity,temperature,turbidity and nutrient content) had been continuously monitored to reveal the influence of the impounding process of the TGR on the water eutrophication in the Xiangxi Bay(XXB).The maximal daily rise of the water level of the TGR was about 2.38 *** water exchange between the mainstream(the Changjiang River) and the XXB of the TGR was enhanced by density current,and its main characteristics were a density-stratified flow in different *** water exchange reduced the differences of the water quality parameters(for example,temperature,turbidity,nutrient level,pH,etc.) between the mainstream and the XXB during the impounding ***,the water stability index in the mainstream remained small but it was lowered in the *** main causes included the dilution by water of lower concentration of the chlorophyll a(Chl.a) entering from the mainstream,the decline of the water stability,and the increase of suspended silt,which induced the Chl.a to decrease in the XXB during the impounding *** grade of the water eutrophication changed from middle eutrophic level to mesotrophic state in the ***,as available nutrients were imported into the XXB from the mainstream during the impounding process the risk of water eutrophication increases in the XXB in the future.

关键词： impounding density current eutrophication the Xiangxi Bay the Three Gorges Reservoir