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Surface water resource attenuation attribution and patterns in Hai River Basin

Science China Earth Sciences 2024年第5期67卷 1545-1560页

作者： Qingming WANG Yong ZHAO Hao WANG Jiaqi ZHAI Yue ZHANG Fan HE Rong LIU Mengyang MA State Key Laboratory of Simulation and Regulation of water Cycle in River Basin China Institute of Water Resources and Hydropower Research(IWHR)Beijing 100038China Key Laboratory of water Safety for Beijing-Tianjin-Hebei Region of Ministry of water resources Beijing 100038China general {1. of water resources and hydropower planning and design Ministry of Water ResourcesBeijing 100120China

From 1.56 to 201.,Hai River Basin suffered the most severe surface water resource attenuation among the 1. first-class river basins in *** on the surface water circulation process,and evolving characteristics of precipitation and underlying surface in Hai River Basin,this study attributed the causes of surface water resource attenuation to six primary impact factors,analyzed each factor's quantitative contribution,and revealed four patterns of surface water resource attenuation in Hai River *** pattern of the dominant factor:comparing the 1.80–2000 period with the 1.56–1.79period,the variation of precipitation is the dominant factor of which contribution is 7 billion m^(3),accounting for 59%of total1..7 billion m^(3);comparing the 2001.201. period with the 1.56–1.79 period,the increasing of vegetation cover in mountainous area is the dominant factor of which contribution is 2.78 billion m3,accounting for 51.of total 4.9 billion m^(3).The pattern of spatial distributions:comparing the 2001.201. period with the 1.56–1.79 period,mountainous areas were more affected by increasing vegetation cover which for example contributed 42%in Luan River Basin mountainous;the plains were more impacted by farmland ridge interception which for example contributed 51.in Beisi River Basin *** pattern of attenuation trend:comparing the 2001.201. period with the 1.80–2000 period,surface water resources in mountainous areas continued to decline,owing to the increasing water consumption of large-scale vegetation restoration,while the influence of the underlying surface changes on surface water resources in plains areas tended to remain *** pattern of reversible change:among factors led to surface water resource attenuation,the human activity,including vegetation cover increase,farmland ridge interception,and urbanization expansion,contributed 36%of the attenuation,which resulted in the variation of precipitation-runoff *** study improved the traditiona

关键词： Hai River Basin Surface water {1. Contribution decomposition Quantitative contribution Attenuation patterns

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Calculation of Mass Concrete Temperature and Creep Stress under the Influence of Local Air Heat Transfer

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2977-3000页

作者： Heng Zhang Chao Su Xiaohu Chen Zhizhong Song Weijie Zhan Academy of Science and Technology Changjiang Institute of Survey Planning Design and ResearchWuhan430010China College of water Conservancy and {1. Engineering Hohai UniversityNanjing210098China Chief Engineer Office Wujiang Company of Goupitan Power Construction CooperationYuqing564408China

Temperature-induced cracking during the construction of mass concrete is a significant *** simulations of concrete temperature have primarily assumed that the concrete is placed in an open *** problem of heat transfer between the air and concrete has been simplified to the concrete’s heat dissipation ***,in the case of tubular concrete structures,where air inlet and outlet are relatively limited,the internal air temperature does not dissipate promptly to the external environment as it *** accurately simulate the temperature and creep stress in tubular concrete structures with enclosed air spaces during construction,we establish an air–concrete coupled heat transfer model according to the principles of conjugate heat transfer,and the accuracy of the model is verified through ***,we conduct a case study to analyze the impact of airflow within the ship lock corridor on concrete temperature and creep *** results demonstrate that enhancing airflow within the corridor can significantly reduce the maximum concrete *** with cases in which airflow within the corridor is neglected,the maximum concrete temperature and maximum tensile stress can be reduced by 1..5℃ and 0.7 MPa,respectively,under a wind speed of 4 m/*** results of the traditional calculation method are relatively close to those obtained at a wind speed of 1.m/***,the temperature reduction process in the traditional method is faster,and the method yields greater tensile stress values for the corridor location.

关键词： Conjugate heat transfer temperature field mass concrete creep stress

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Investigation of the 5.1. Wenchuan Earthquake damages to the Zipingpu water Control Project and an assessment of its safety state

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Science China(Technological Sciences) 2009年第4期52卷 820-834页

作者： GUAN ZhiCheng water {1. and hydropower planning & design general institute, Beijing1.01.0, China 1. water resources and hydropower planning & design general institute Beijing 100120 China

On May 1., 2008, a major earthquake measured 8 on the Richter scale jolted Wenchuan County in Si- chuan Province, China with the epicentral intensity of XI degrees. Zipingpu Dam is located 1..1. km from the epicenter and the influence intensity at the damsite reached IX―X degrees. It is the first time in the world for such a high concrete-faced rockfill dam (CFRD) in China to experience such a strong earthquake occurring in such a short distance. Due to its location of special importance to the down- stream areas, the safety state and damaging condition of the Zipingpu Dam has attracted great atten- tions from various circles. Based on site investigation of the damages to the Zipingpu Dam and com- parison analysis of the observation data obtained before and after the earthquake, the paper makes a comprehensive assessment of the key technical issues relevant to this high CFRD, including its safety state and the high slope stability after the earthquake.

关键词： earthquake earthquake damage investigation concrete-faced rockfill dam dam project safety state Zipingpu Dam

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Advancing flood susceptibility modeling using stacking ensemble machine learning: A multi-model approach

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Journal of Geographical Sciences 2024年第8期34卷 1513-1536页

作者： YANG Huilin YAO Rui DONG Linyao SUN Peng ZHANG Qiang WEI Yongqiang SUN Shao AGHAKOUCHAK Amir School of Geography and Tourism Anhui Normal UniversityWuhu 241002AnhuiChina Changjiang River Scientific Research institute Wuhan 430015China Advanced Interdisciplinary institute of Environment and Ecology Beijing Normal UniversityZhuhai 519087GuangdongChina Hunan institute of {1. resources and hydropower Research Changsha 410007China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Department of Civil and Environmental Engineering University of California IrvineIrvineCA 92697USA

Flood susceptibility modeling is crucial for rapid flood forecasting, disaster reduction strategies, evacuation planning, and decision-making. Machine learning(ML) models have proven to be effective tools for assessing flood susceptibility. However, most previous studies have focused on individual models or comparative performance, underscoring the unique strengths and weaknesses of each model. In this study, we propose a stacking ensemble learning algorithm that harnesses the strengths of a diverse range of machine learning models. The findings reveal the following:(1. The stacking ensemble learning, using RF-XGBCB-LR model, significantly enhances flood susceptibility simulation.(2) In addition to rainfall,key flood drivers in the study area include NDVI, and impervious surfaces. Over 40% of the study area, primarily in the northeast and southeast, exhibits high flood susceptibility, with higher risks for populations compared to cropland.(3) In the northeast of the study area,heavy precipitation, low terrain, and NDVI values are key indicators contributing to high flood susceptibility, while long-duration precipitation, mountainous topography, and upper reach vegetation are the main drivers in the southeast. This study underscores the effectiveness of ML, particularly ensemble learning, in flood modeling. It identifies vulnerable areas and contributes to improved flood risk management.

关键词： flood susceptibility assessment machine learning stacking ensemble learning flood drivers XiangjiangRiverBasin

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SIMULATION OF THE ATOMIZED FLOW BY SLIT TYPE BUCKET ENERGY DISSIPATOR

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Journal of Hydrodynamics 2005年第6期17卷 758-763页

作者： LIU Shi-he DUAN Hong-dong School of water Resource and {1. Wuhan University Wuhan 430072 China water {1. and hydropower planning and design general institute MWR Beijing 100011 China

Slit type bucket is one kind of flip bucket for energy dissipation generally used in the hydraulic project. In this paper the atomized flow produced behind this energy dis sipator is analyzed, a numerical model for the aerated jet con sidering air entrainment and air resistance force is suggested, and simulation of the rain resulted by the atomized flow is also discussed. Furthermore, the prototype observation data for the atomized flow of Dongjiang {1. Station is used to verify the model suggested.

关键词： two phase flow atomized flow slit type energy dissipator

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RAIN INTENSITY DISTRIBUTION IN THE SPLASH REGION OF ATOMIZED FLOW

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Journal of Hydrodynamics 2006年第3期18卷 362-366页

作者： DUAN Hong-dong LIU Shi-he LUO Qiu-shi HUANG Wei School of water Resource and {1. Wuhan University Wuhan 430072China water {1. and hydropower planning and design general institute MWR Beijing 100011 China

Atomized flow is an unnatural two-phase flow produced while water discharges in water release structures. This flow might threaten the normal operation of hydraulic and hydroelectric installations owing to the unnatural and high-density rain as well as the unnatural and dirty mist. The splash region, the region with the highest rain intensity, hence should receive much attention during the design and operation of the hydraulic and hydroelectric installations. In this paper rain intensity distribution in the splash region of the atomized flow is investigated experimentally, and the method of random simulation is used to predict the rain intensity distribution in the splash region.

关键词： atomized flow splash rain intensity

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Basin-scale exposure risk of psychiatric pharmaceuticals and illicit drugs in tap water in Eastern China

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Emerging Contaminants 2024年第3期10卷 40-45页

作者： Wei Wang Zeyuan Wang Feng Chen Fangxing Yang Zhejiang institute of Hydraulics&Estuary(Zhejiang institute of Marine planning and design) Hangzhou310008China Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou310012China Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationCollege of Natural Resources and Environmental ScienceZhejiang University310058HangzhouChina Hangzhou Ecological and Environmental Monitoring Center of Zhejiang Province 310058HangzhouChina Innovation Center of Yangtze River Delta Zhejiang University314100JiashanChina

A total of twenty-three psychiatric pharmaceuticals and illicit drugs were analyzed in tap water covering seven basins in Eastern *** residual concentrations of these substances were detected up to 22.4 ng L^(-1..Among the substances,benzodiazepines were more often detected with higher median concentrations than those of illicit ***,the higher residual levels of psychoactive substances were detected in the upstream of the basins compared with the *** example,the concentrations of diazepam,temazepam,and oxazepam in the downstream were much higher than those in the upstream in *** the basins,YH was the most polluted *** assessment indicated the median exposure doses of diazepam and temazepam were from 85 to 99 and 3.5e4.1.pg kg^(-1. bw d^(-1. in the basins,*** quotient for the nine detected substances was calculated in each basin with the range from 0.0001.to 0.0389,indicating low risk in the tap water for human health under current concentrations.

关键词： Psychiatric pharmaceuticals Illicit drugs Psychoactive substances Tap water Risk assessment

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Random　process　simulation　of　strong　ground　motion

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Acta Seismologica Sinica(English Edition) 1995年第1期8卷 127-134页

作者：杜修力胡晓陈厚群 1. institute of {1. resources and hydropower Research 100044 Beijing China

The state-of-art of random process simulation model research of strong ground motion are analysed and theshortcomings of previous models is pointed out in this paper. Based on these, a random process model of groundmotion with color spectrum on bedrock is presented which can give expression to the recent results in engineeringseismology and near-field seismology and simulate the practical spectrum function of strong ground motion aswell. Moreover, the presented model can solve the incompatible problem between the horizontal model and therotational model, and it is easy to determine the model parameters and to set up a practical design criterion ofrandom seismic motion by use of the basic parameters used in the present aseismic design.

关键词： strong earthquake stochastic process. power spectrum mathematical modelling

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Parameters inversion of high central core rockfill dams based on a novel genetic algorithm

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Science China(Technological Sciences) 2016年第5期59卷 783-794页

作者： ZHOU Wei LI Shao Lin MA Gang CHANG Xiao Lin MA Xing ZHANG Chao State Key Laboratory of water {1. and hydropower Engineering Science Wuhan University Changjiang institute of Survey Planning Design and Research

Parameters identification of rockfill materials is a crucial issue for high rockfill dams. Because of the scale effect, random sampling and sample disturbance, it is difficult to obtain the actual mechanical properties of rockfill from laboratory tests. Parameters inversion based on in situ monitoring data has been proven to be an efficient method for identifying the exact parameters of the rockfill. In this paper, we propose a modified genetic algorithm to solve the high-dimension multimodal and nonlinear optimal parameters inversion problem. A novel crossover operator based on the sum of differences in gene fragments(So DX) is proposed, inspired by the cloning of superior genes in genetic engineering. The crossover points are selected according to the difference in the gene fragments, defining the adaptive length. The crossover operator increases the speed and accuracy of algorithm convergence by reducing the inbreeding and enhancing the global search capability of the genetic algorithm. This algorithm is compared with two existing crossover operators. The modified genetic algorithm is then used in combination with radial basis function neural networks(RBFNN) to perform the parameters back analysis of a high central earth core rockfill dam. The settlements simulated using the identified parameters show good agreement with the monitoring data, illustrating that the back analysis is reasonable and accurate. The proposed genetic algorithm has considerable superiority for nonlinear multimodal parameter identification problems.

关键词： rockfill dam parameters back analysis genetic algorithm crossover operator sum of differences in gene fragments

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Method for determination of allocable water during formulation of water allocation scheme

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Science China(Technological Sciences) 2011年第10期54卷 2629-2637页

作者： YIN ZhiJie GUAN YuHui LI YuanYuan College of Hydrology and water {1. Hohai University Nanjing 210098 China Bureau of Hydrology Ministry of Water Resources Beijing 100053 China water {1. and hydropower planning and design general institute MWR Beijing 100120 China

The determination of allocable water is one of the most important stages during the process of formulating water allocation *** selection of appropriate allocable water is the prerequisite and fundament for developing a reasonable water allocation *** on the summary and analysis of international water allocation practice,this paper has distilled three attention-worth issues concerning the determination of allocable *** addition,this paper has also proposed a general method for the determination of allocable water and illustrated this method in *** is hoped that through providing a general and feasible method for determining allocable water,a fundament could be established for the consultation of water allocation process among different stakeholders,promoting the integrated management of river basins.

关键词： water allocation allocable water surface water allocation scheme

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