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Dam risk assistant analysis system design

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Science china(Technological Sciences) 2008年第S2期51卷 101-109页

作者： HE XianFeng1,2,3,GU ChongShi3,4,WU ZhongRu3,4 & SU HuaiZhi3,4 1 yellow river institute of hydraulic research,zhengzhou 450003,china 2 Embankment Security Defect Prevention and Control Engineering research Center of MWR,zhengzhou 45000,china 3 College of Water Resources and Hydropower Engineering,Hohai University,Nanjing 210098,china 4 National Engineering research Center of Water Resources Efficient Utilization and Engineering Safety,Hohai University,Nanjing 210098,china yellow river institute of hydraulic research Zhengzhou China Embankment Security Defect Prevention and Control Engineering research Center of MWR Zhengzhou China College of Water Resources and Hydropower Engineering Hohai University Nanjing China National Engineering research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing China

In order to reduce the labor intensity and task difficulty of dam risk analysis and to meet the actual requirement of dam risk analysis,it is necessary to establish a dam risk assistant analysis *** program structure and the implementation ways of the dam risk assistant analysis system are analyzed,and a procedural framework with "three-tier and multi-database" structure and "level structure" is *** concept of dam risk assessment system modular development is proposed and the coupled mode of function module and data is ***,the dam risk assistant analysis system is developed using Delphi visual programming language.

关键词： dam risk risk analysis assistant analysis system

土壤持水曲线van Genuchten模型求参的Matlab实现

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土壤学报 2004年第3期41卷 380-386页

作者：魏义长刘作新康玲玲王云璋时明立中国科学院沈阳应用生态研究所中国科学院研究生院北京100039 黄河水利科学研究院

土壤持水曲线是研究土壤水力学性质必不可少的 ,在已经建立的众多数学模型中 ,vanGenuchten模型是目前运用最广泛的模型 ,而运用该模型的关键是其 4个参数的求解。为此 ,本文对同一组东北褐土的土壤水吸力和对应的土壤含水量数据较详细... 详细信息

土壤持水曲线是研究土壤水力学性质必不可少的 ,在已经建立的众多数学模型中 ,vanGenuchten模型是目前运用最广泛的模型 ,而运用该模型的关键是其 4个参数的求解。为此 ,本文对同一组东北褐土的土壤水吸力和对应的土壤含水量数据较详细地介绍了Matlab软件的非线性拟合和非线性回归函数的运用 ,得出了该土壤vanGenuchten模型的 4个参数值 ,分别建立了该土壤的vanGenuchten模型 ,并利用Mat lab强大的绘图功能对它们进行了直观比较。最后运用方差分析和残差分析对该模型的计算值与实测数据进行了分析 ,结果表明 :非线性拟合和非线性回归函数求参结果的显著水平均达到p<0 0 0 0 1,残差平方和均小于 0 0 0 0 5 ,其中非线性回归函数的求参结果较非线性拟合好。因此 ,运用Matlab软件的非线性拟合和非线性回归函数对土壤持水曲线的vanGenuchten模型进行求参是切实可行的 ,从而为土壤学工作者寻求出了一条运用数值计算方法的新途径。

关键词：土壤持水曲线 van Genuchten模型 Matlab 非线性拟合非线性回归土壤水力学性质

Response of flood discharging capacity to the deterioration of the lower yellow river

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Science china(Technological Sciences) 2004年第Z1期47卷 152-160页

作者： LI Wenxue1, LI Yong2, YAO Wenyi2, SU Yunqi2 & ZHANG Xiaohua2 1. yellow river Engineering Consulting Co. Ltd., zhengzhou 450003, china 2. yellow river institute of hydraulic research, zhengzhou 450003, china yellow river Engineering Consulting Co. Ltd. Zhengzhou China yellow river institute of hydraulic research Zhengzhou China

Based on the clarifications of the deterioration characteristics of the lower yellow river (LYR), the influence of river deterioration on flood discharging capacity is studied through theoretical derivation and analysis of field data. This study indicates that response of flood discharging capacity to river deterioration is nonlinear. Sediment depositions in the main channel cause the reductions of dominant discharge and thus the increase of initial flood stage. Reductions in the channel width result in the increases of the rising rate of flood stage and the decrease of flood discharging capacity.

关键词： flood discharging capacity, boundary condition, deterioration, sediment, the lower yellow river.

Runoff reduction due to environmental changes in the Sanchuanhe river basin

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International Journal of Sediment research 2008年第2期23卷 174-180页

作者： Guoqing WANG1,Jianyun ZHANG2,Ruimin HE3,Naiqian JIANG4,and Xin'ai JING5 1 Senior Engineer,State Key Laboratory of Hydrology-Water Resources and hydraulic Engineering,Nanjing hydraulic research institute,Nanjing 210098,china research Center for Climate Change,MWR,Nanjing 210029,china yellow river institute of hydraulic research,zhengzhou 450003,china 2 Prof.,3 Engineer,State Key Laboratory of Hydrology-Water Resources and hydraulic Engineering,Nanjing hydraulic research institute,Nanjing 210098,china 4 Prof.,5 Engineer,yellow river institute of hydraulic research,zhengzhou 450003,china Senior Engineer State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing 210098 China research Center for Climate Change MWR Nanjing 210029 China yellow river institute of hydraulic research Zhengzhou 450003 China Prof. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing 210098 China Engineer State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing 210098 China Prof. Yellow River Institute of Hydraulic Research Zhengzhou 450003 China Engineer Yellow River Institute of Hydraulic Research Zhengzhou 450003 China

Recently,runoff in many river basins in china has been ***,the role that climate change and human activities are playing in this decrease is currently of *** this study,we evaluated an assessment method that was designed to quantitatively separate the effects of climate change and human activities on runoff in river ***,we calibrated the SIMHYD rainfall runoff model using naturally recorded hydro-meteorologic data pertaining to the Sanchuanhe river basin and then determined the effects of climate change and human activities on runoff by comparing the estimated natural runoff that occurred during the period in which humans disturbed the basin to the runoff that occurred during the period prior to disturbance by *** results of this study revealed that the SIMHYD rainfall runoff model performs well for estimating monthly *** addition,we found that absolute runoff reductions have increased in response to human activities and climate change,with average reductions of 70.1% and 29.9% in total runoff being caused by human activities and climate change,*** together,the results of this study indicate that human activities are the primary cause of runoff reduction in the Sanchuanhe river basin.

关键词： Sanchuanhe river Hydrological simulation Climate change Human activities Impact

SIZE DISTRIBUTIONS OF COARSE SAND BED LOAD IN TURBULENT FLOW FIELD

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Journal of Hydrodynamics 1995年第3期7卷 1-6页

作者： Zhang Hong-wu Wang Shan(institute of hydraulic research yellow river Conservancy Commissivn,zhengzhou 450003,P.R.china)

Putting forth effort on analyzing the action of turbulent flow on the sand particles on rvier bed surface,in this paper, the interdependent relation between the size distribution of coarse sand bed load and flow stren... 详细信息

关键词： coarse sand bed size distributions turbulent flow

Large-eddy simulation of formation of three-dimensional aeolian sand ripples in a turbulent field

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 945-960页

作者： WU ChuiJie1,WANG Ming2 & WANG Liang3 1 State Key Laboratory of Structural Analysis for Industrial Equipment,Dalian University of Technology,Dalian 116024,china 2 yellow river institute of hydraulic research,zhengzhou 450003,china 3 research Center for Fluid Dynamics,Science School,PLA University of Science and Technology,Nanjing 211101,china State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian China yellow river institute of hydraulic research Zhengzhou China research Center for Fluid Dynamics Science School PLA University of Science and Technology Nanjing China

With the method of large-eddy simulation,the equation of spherule motion and the method of immersed boundary condition,numerical simulations of three-dimen-sional turbulent aeolian motion and the formation of sand ripples under three-di-mensional turbulent wind and the mutual actions of saltation and creeping motion were carried out. The resulting sand ripples have the form that is flat on the upwind side and steep on the leeward,which is identical to the sand ripples in nature. We also realized the self-restoration process of three-dimensional sand ripples,which shows the correctness of the method of numerical simulation and the models of saltation and creeping. Finally,We analyzed the influence of sand ripples on the three-dimensional turbulent wind field,and found that due to the appearance and development of sand ripples,in the normal direction of ground there exists stronger energy exchange,and moreover,there is close correspondence between the forms of sand ripples and the vorticity close to the ground surface.

关键词： large-eddy simulation equation of spherule motion sand ripples saltation creep

A distributed hydrological model with its application to the Jinghe watershed in the yellow river Basin

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Science china(Technological Sciences) 2004年第Z1期47卷 60-71页

作者： WANG Zhonggen1, ZHENG Hongxing1, LIU Changming1, , WU Xianfeng2 2 & ZHAO Weimin3 1. Key Laboratory of Water Cycle & Related Land Surface Processes, institute of Geographic Science and Natural Resources research, Chinese Academy of Sciences, Beijing 100101, china 2. institute of Environmental Science, Beijing Normal University, Beijing 100875, china 3. Water Resources Conservation Committee of yellow river, zhengzhou 450003, china Key Laboratory of Water Cyde & Related Land Surface Processes Institute of Geographic Science and Natural Resources Research Chinese Academy of Sciences Beijing China institute of Environmental Science Beijing Normal University Beijing China Water Resources Conservation Committee of yellow river Zhengzhou China

For the purpose of water resources management in the yellow river Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle yellow river Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, yellow river Basin.

Soil erosion and sediment transport in the gullied Loess Plateau:Scale effects and their mechanisms

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Science china(Technological Sciences) 2009年第5期52卷 1283-1292页

作者： LI TieJian1,WANG GuangQian1,XUE Hai2,3 & WANG Kai4 1 State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,china 2 yellow river Engineering Consulting Co.,Ltd.,zhengzhou 450003,china 3 North china institute of Water Conservancy and Hydropower,zhengzhou 450008,china 4 china institute of Water Resources and Hydropower research,Beijing 100038,china State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing China yellow river Engineering Consulting Co. Ltd. Zhengzhou China North china institute of Water Conservancy and Hydropower Zhengzhou China china institute of Water Resources and Hydropower research Beijing China

Scale effects exist in the whole process of rainfall-3-runoff-3-soil erosion-3-sediment transport in river basins. The differences of hydrographs and sediment graphs in different positions in a river basin are treated as basic scale effects, which are more complex in the gullied Loess Plateau, a region notorious for high intensity soil erosion and hyper-concentrated sediment-laden flow. The up-scaling method of direct extrapolation that maintains dynamical mechanism effective in large scale application was chosen as the methodology of this paper. Firstly, scale effects of hydrographs and sediment graphs were analyzed by using field data, and key sub-processes and their mechanisms contributing to scale effects were clearly defined. Then, the Digital yellow river Model that integrates sub-models for the subprocesses was used with high resolution to simulate rainfall-3-runoff-3-soil erosion-3-sediment transport response in Chabagou watershed, and the distributed results representing scale effects were obtained. Finally, analysis on the simulation results was carried out. It was shown that gravitational erosion and hyper-concentrated flow contribute most to the spatial variation of hydrographs and sediment graphs in the spatial scale. Different spatial scale distributions and superposition of different sub-processes are the mechanisms of scale effects.

关键词： scale effect soil erosion hyper-concentrated sediment-laden flow the Loess Plateau

DEFORMATION OF river BED AND THE CHARACTERISTICS OF SEDIMENT TRANSPORT DURING HYPER-CONCENTRATED FLOOD IN THE yellow river

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International Journal of Sediment research 1997年第3期 72-79页

作者： Wenxue LI Senior engineer, institute of hydraulic research, yellow river Conservancy Commission, zhengzhou 450003, china PU QI Senior engineer. institute of hydraulic research, yellow river Conservancy Commission, zhengzhou 450003, china Zanying SUN E

Analysis of field data indicated that channel resistant force during hyper-concentrated flood can be computed by Manning’s equation. The dominant factor which controls sediment transport is the channel configuration. Sediment transporting capacity in narrow and deep channel is potentially large. The suitable sediment concentration for transporting ranges from 300 kg/m3 to 800 kg/m3 and the most difficult situation occurs at 200 kg/m3. When hyperconcentrated flood transports through wide and shallow river, the main channel of the river becomes deeper and narrower due to deposition on flood plain and erosion in the channel. Thus, sediment carring capacity increases and so does the speed of flood propagation.

关键词： Hyper-concentrated flood Sediment transport the yellow river