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基于MIKE HYDRO River模型的轨交交通施工期防汛安全影响论证
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作者 陆娴 《价值工程》 2024年第4期143-145,共3页
轨交交通施工期间,受车站结构设计、周边场地限制等因素影响,河道需要断流施工,断流会对区域的防洪除涝安全及水环境产生影响。本文以上海轨道交通13号线西延伸工程为例,构建一维河网水动力模型,分析排涝及引调水工况下水位及水质变化... 轨交交通施工期间,受车站结构设计、周边场地限制等因素影响,河道需要断流施工,断流会对区域的防洪除涝安全及水环境产生影响。本文以上海轨道交通13号线西延伸工程为例,构建一维河网水动力模型,分析排涝及引调水工况下水位及水质变化情况。结果表明,平原河网地区个别河道断流对于区域防洪除涝安全影响较小,会严重影响河道断流处的水环境;通过增设导流措施可以减轻断流的影响,为平原河网地区河道断流影响分析及措施制定提供依据。 展开更多
关键词 轨交交通 平原河网 MIKE HYDRO river 防汛安全 水环境改善
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Joint optimization scheduling for water conservancy projects incomplex river networks 被引量:6
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作者 Qin Liu Guo-hua Fang +1 位作者 Hong-bin Sun Xue-wen Wu 《Water Science and Engineering》 EI CAS CSCD 2017年第1期43-52,共10页
In this study, we simulated water flow in a water conservancy project consisting of various hydraulic structures, such as sluices, pumping stations, hydropower stations, ship locks, and culverts, and developed a multi... In this study, we simulated water flow in a water conservancy project consisting of various hydraulic structures, such as sluices, pumping stations, hydropower stations, ship locks, and culverts, and developed a multi-period and multi-variable joint optimization scheduling model for flood control, drainage, and irrigation. In this model, the number of sluice holes, pump units, and hydropower station units to be opened were used as decision variables, and different optimization objectives and constraints were considered. This model was solved with improved genetic algorithms and verified using the Huaian Water Conservancy Project as an example. The results show that the use of the joint optimization scheduling led to a 10% increase in the power generation capacity and a 15% reduction in the total energy consumption. The change in the water level was reduced by 0.25 m upstream of the Yundong Sluice, and by 50% downstream of pumping stations No. 1, No. 2, and No. 4. It is clear that the joint optimization scheduling proposed in this study can effectively improve power generation capacity of the project, minimize operating costs and energy consumption, and enable more stable operation of various hydraulic structures. The results may provide references for the management of water conservancy projects in complex river networks. 展开更多
关键词 Complex river network Water conservancy project Hydraulic structure Flow capacity simulation Scheduling model Optimal scheduling
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Relationship Between Changes of River-lake Networks and Water Levels in Typical Regions of Taihu Lake Basin,China 被引量:6
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作者 YIN Yixing XU Youpeng CHEN Ying 《Chinese Geographical Science》 SCIE CSCD 2012年第6期673-682,共10页
The typical regions of the Taihu Lake Basin,China,were selected to analyze the variation characteristics of river-lake networks under intensive human activities.The characteristics of the fractal dimension of river ne... The typical regions of the Taihu Lake Basin,China,were selected to analyze the variation characteristics of river-lake networks under intensive human activities.The characteristics of the fractal dimension of river networks and lakes for different periods were investigated and the influences of river system evolution on water level changes were further explored through the comparison of their fractal characters.The results are as follows:1) River network development of the study area is becoming more monotonous and more simple;the number of lakes is reducing significantly,and the water surface ratio has dropped significantly since the 1980s.2) The box dimension of the river networks in all the cities of the study area decreased slowly from the 1960s to the 1980s,while the decrease was significant from the 1980s to the 2000s.The variations of lake correlation dimension are similar to those of the river network box dimensions.This is unfavorable for the storage capacity of the river networks and lakes.3) The Hurst exponents of water levels were all between 0.5 and 1.0 from the 1960s to the 1980s,while decreased in the 2000s,indicating the decline in persistence and increase in the complexity of water level series.The paper draws a conclusion that the relationship between the fractal dimension of river-lake networks and the Hurst exponents of the water level series can reveal the impacts of river system changes on flood disasters to some extent:the disappearance of river networks and lakes will increase the possibility of flood occurrence. 展开更多
关键词 river network LAKE water level changes FRACTAL Taihu Lake Basin
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Distribution characteristics and controlling factors of typical antibiotics and antibiotic resistance genes in river networks in western area of Wangyu River,China 被引量:2
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作者 Jing-jing Zhang Juan Chen +3 位作者 Chao Wang Pei-fang Wang Han Gao Yu Hu 《Water Science and Engineering》 EI CAS CSCD 2022年第4期318-327,共10页
Antibiotics and antibiotic resistance genes(ARGs)pose health risks in aquatic environments because of their persistence and mobility.River networks can provide a perfect opportunity for exploring the occurrence and en... Antibiotics and antibiotic resistance genes(ARGs)pose health risks in aquatic environments because of their persistence and mobility.River networks can provide a perfect opportunity for exploring the occurrence and enrichment of ARGs and antibiotics in freshwater environments.On this basis,the abundances of four types of antibiotics(sulfonamides,quinolones,tetracyclines,and macrolides)and 13 ARGs(sulⅠ,sulⅡ,tetA,tetB,tetO,tetW,qnrA,qnrS,qnrD,ermB,ermF,ermC,and ere A)were measured in the river networks of the west bank of the Wangyu River in China.The spatial distribution and temporal variation of these antibiotics and ARGs were characterized,and their controlling factors were analyzed.All four types of antibiotics were detected with high frequencies between 41%and 100%.Quinolone antibiotics exhibited the highest average concentration(286.53 ng/L).The concentrations of quinolones,tetracyclines,and macrolides were significantly higher in the winter than in the summer,whereas the concentration of sulfonamides was higher in wet periods than in dry periods.Of the 13 ARGs,sulⅠwas the most abundant(1.28 x 10^(5)copies per milliliter),followed by sulⅡand tetO(5.41×10^(4)and 4.45×10^(4)copies per milliliter,respectively).The canonical correspondence analysis showed that environmental factors,including dissolved oxygen,water temperature,total nitrogen,pH,and total phosphorus,had significant effects on the abundance of ARGs.sulⅠ,sulⅡ,tetA,and tetB were significantly correlated with 16S ribosomal RNA sequences,indicating that the bacterioplankton community might affect the distribution of ARGs.The correlation heat map analysis showed that the spread of ARGs was influenced by specific bacterial groups,such as Acidobacteria and Cyanobacteria,indicating that these bacterioplankton may be the hosts of environmental ARGs. 展开更多
关键词 Wangyu river Antibiotic ARG Distribution characteristic Environmental factor river network
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Regional accessibility of land traffic network in the Yangtze River Delta 被引量:9
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作者 ZHANG Li LU Yuqi 《Journal of Geographical Sciences》 SCIE CSCD 2007年第3期351-364,共14页
In a given district, the accessibility of any point should be the synthetically evaluation of the internal and external accessibilities. Using MapX component and Delphi, the author presents an information system to ca... In a given district, the accessibility of any point should be the synthetically evaluation of the internal and external accessibilities. Using MapX component and Delphi, the author presents an information system to calculate and analyze regional accessibility according to the shortest travel time, generating thus a mark diffusing figure. Based on land traffic network, this paper assesses the present and the future regional accessibilities of sixteen major cities in the Yangtze River Delta. The result shows that the regional accessibility of the Yangtze River Delta presents a fan with Shanghai as its core. The top two most accessible cities are Shanghai and Jiaxing, and the bottom two ones are Taizhou (Zhejiang province) and Nantong With the construction of Sutong Bridge, Hangzhouwan Bridge and Zhoushan Bridge, the regional internal accessibility of all cities will be improved. Especially for Shaoxing, Ningbo and Taizhou (Jiangsu province), the regional internal accessibility will be decreased by one hour, and other cities will be shortened by about 25 minutes averagely. As the construction of Yangkou Harbor in Nantong, the regional external accessibility of the harbor cities in Jiangsu province will be speeded up by about one hour. 展开更多
关键词 regional accessibility land traffic network Yangtze river Delta GIS
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A Method of Catchments Health Assessment under Value-pressure Model and Its Application in Urbanized River Network Area:A Case Study in Shanghai,China
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作者 YUAN Wen YANG Kai 《Chinese Geographical Science》 SCIE CSCD 2011年第1期102-109,共8页
Catchments health assessment is fundamental to effective catchments management. Generally, an assessment method should be selected to reflect both the purpose of assessment and local characteristics. A trial in Shangh... Catchments health assessment is fundamental to effective catchments management. Generally, an assessment method should be selected to reflect both the purpose of assessment and local characteristics. A trial in Shanghai was conducted to test the method for catchments health assessment in urbanized fiver network area. Seven indicators that described four dimensions of river, river network, land use and function, and local feature were used to assess catchments values; while possible change rate of urbanization and industrialization in the next 3 years were chosen for catchments pressure assessment in the value-pressure model. Factors related to catchments classification, indicators measurement and protection priority have been considered in the development strategies for catchments health management. The results showed that value-pressure assessment was applicable in urbanized catchments health management, particularly when both human and catchments had multiple demands. As a result of over 30-year rapid urbanization, more than 70% of Shanghai fiver network area was still in a healthy condition with high catchments values, among them, 39.3% was under high pressure. Poor water quality, simplified river system and weakened local feature of fiver pattern had largely affected catchments health in Shanghai. Lack of long-term monitoring data would seriously restrict the development and validity of catchments health assessment. 展开更多
关键词 catchments health assessment value-pressure model river network area SHANGHAI
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Water level updating model for flow calculation of river networks
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作者 Xiao-ling WU Xiao-hua XIANG +1 位作者 Li LI Chuan-hai WANG 《Water Science and Engineering》 EI CAS CSCD 2014年第1期60-69,共10页
Complex water movement and insufficient observation stations are the unfavorable factors in improving the accuracy of flow calculation of river networks. A water level updating model for river networks was set up base... Complex water movement and insufficient observation stations are the unfavorable factors in improving the accuracy of flow calculation of river networks. A water level updating model for river networks was set up based on a three-step method at key nodes, and model correction values were collected from gauge stations. To improve the accuracy of water level and discharge forecasts for the entire network, the discrete coefficients of the Saint-Venant equations for river sections were regarded as the media carrying the correction values from observation locations to other cross-sections of the river network system. To examine the applicability, the updating model was applied to flow calculation of an ideal river network and the Chengtong section of the Yangtze River. Comparison of the forecast results with the observed data demonstrates that this updating model can improve the forecast accuracy in both ideal and real river networks. 展开更多
关键词 plain river network cyclic looped channel network water level updating model hydrodynamic model error correction
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Determining Critical Support Discharge of a Riverhead and River Network Analysis: Case Studies of Lhasa River and Nyangqu River
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作者 SHA Yukun LI Weipeng +1 位作者 FAN Jihui CHENG Genwei 《Chinese Geographical Science》 SCIE CSCD 2016年第4期456-465,共10页
A riverhead is the demarcation point of continuous water channel and seasonal channel, which is characterized by a criti- cal flow that can support a continuous water body. In this study, the critical support dischar... A riverhead is the demarcation point of continuous water channel and seasonal channel, which is characterized by a criti- cal flow that can support a continuous water body. In this study, the critical support discharge (CSD) is defined as the critical steady flows required to form the origin of a stream. The CSD is used as the criterion to determine the beginning of the riverhead, which can be controlled by hydro-climate factors (e.g., annual precipitation, annual evaporation, or minimum stream flow in arid season). The CSD has a close correlation with the critical support/source area (CSA) that largely affects the density of the river network and the division of sub-watersheds. In general, river density may vary with regional meteorological and hydrological conditions that have to be considered in the analysis. In this paper, a new model referring to the relationship of CSA and CSD is proposed, which is based on the physical mechanism for the origin of riverheads. The feasibility of the model was verified using two watersheds (Duilongqu Basin of the Lhasa River and Beishuiqu Basin of the Nyangqu River) in Tibet Autonomous Region to calculate the CSA and extract river networks. A series of CSAs based on different CSDs in derived equation were tested by comparing the extracted river networks with the reference network obtained from a digitized map of river network at large scales. Comparison results of river networks derived from digital elevation model with real ones indicate that the CSD (equal to criterion of flow quantity (Qc)) are 0.0028 m3/s in Duilongqu and 0.0085 m3/s in Beishuiqu. Results show that the Qc can vary with hydro-climate conditions. The Qc is high in humid region and low in arid region, and the optimal Qo of 0.0085 m3/s in Beishuiqu Basin (humid region) is higher than 0.0028 m3/s in Duilongqu Basin (semi-arid region). The suggested method provides a new application approach that can be used to determine the Qo of a riverhead in complex geographical regions, which can also reflect the effect of hydro-climate change on rivers supply in different regions. 展开更多
关键词 river network extraction Duilongqu Basin of Lhasa river Beishuiqu Basin of Nyangqu river critical support discharge hydro-climate conditions riverhead
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Application of River Network Hydrodynamic Model in Determining Water Distribution Scale of Haishu Plain
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作者 Meijun Huang Sufu Chu Degang Jin 《Journal of Water Resource and Protection》 2022年第4期334-348,共15页
The water distribution network is an important part of the plain water environment improvement system. To make efficient use of the regional water diversion source, scientifically distribute the water diversion flow a... The water distribution network is an important part of the plain water environment improvement system. To make efficient use of the regional water diversion source, scientifically distribute the water diversion flow and improve the water environment carrying capacity of Haishu Plain, the river network hydrodynamic model is used in this paper to simulate the water intake location, reasonable water quantity and influence range of water transfer in Haishu Plain. The simulation results have high accuracy, which can provide a scientific basis for the scale, water transfer mechanism and project layout of water transfer construction in Haishu Plain and show a strong reference value for the study of water diversion and distribution scheme of coastal plain river network. 展开更多
关键词 river network Hydrodynamic Model Water Distribution Planning Water Diversion and Drainage Layout Water Environment Haishu Plain
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Time Series Modeling of River Flow Using Wavelet Neural Networks 被引量:1
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作者 B. Krishna Y. R. Satyaji Rao P. C. Nayak 《Journal of Water Resource and Protection》 2011年第1期50-59,共10页
A new hybrid model which combines wavelets and Artificial Neural Network (ANN) called wavelet neural network (WNN) model was proposed in the current study and applied for time series modeling of river flow. The time s... A new hybrid model which combines wavelets and Artificial Neural Network (ANN) called wavelet neural network (WNN) model was proposed in the current study and applied for time series modeling of river flow. The time series of daily river flow of the Malaprabha River basin (Karnataka state, India) were analyzed by the WNN model. The observed time series are decomposed into sub-series using discrete wavelet transform and then appropriate sub-series is used as inputs to the neural network for forecasting hydrological variables. The hybrid model (WNN) was compared with the standard ANN and AR models. The WNN model was able to provide a good fit with the observed data, especially the peak values during the testing period. The benchmark results from WNN model applications showed that the hybrid model produced better results in estimating the hydrograph properties than the latter models (ANN and AR). 展开更多
关键词 Time SERIES river FLOW WAVELETS NEURAL networkS
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Seismic Prospecting Techniques in Network of Rivers
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《China Oil & Gas》 CAS 1998年第1期52-52,共1页
关键词 Seismic Prospecting Techniques in network of rivers
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Mapping Urban Networks through Inter-Firm Linkages: The Case of Listed Companies in Yangtze River Delta, China
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作者 Yizhen Zhang Weidong Cao Kun Zhang 《Journal of Geoscience and Environment Protection》 2020年第3期23-36,共14页
Recently, literature on urban network research from the perspective of ?rm networks has been increasing. This research mainly used data from the headquarters and branches of all 2581 listed manufacturing companies in ... Recently, literature on urban network research from the perspective of ?rm networks has been increasing. This research mainly used data from the headquarters and branches of all 2581 listed manufacturing companies in the Yangtze River Delta from 1990 to 2017, and studied the urban network through an interlocking network model that quantifies the links between enterprises. The results showed that the spatial distribution of listed manufacturing industries in the Yangtze River Delta was relatively concentrated, and cities such as Shanghai, Nanjing, and Hangzhou were hot spots for the spatial distribution of listed manufacturing industries. However, Fuyang, Suqian, Chizhou, Lishui and other network edge cities were less distributed in manufacturing. The urban network of the Yangtze River Delta has significant hierarchical characteristics. The urban network of the Yangtze River Delta presents a multi-center network development mode with Shanghai as the center and Nanjing, Hangzhou, and Hefei as the sub-centers. Moreover, we found that the development of inter-city connections in the Yangtze River Delta was driven by network mechanisms of priority attachment and path dependence. The radiating capacity and agglomeration capacity of cities in the Yangtze River Delta have a strong polarization characteristic. The core cities such as Shanghai, Nanjing, Hangzhou, and Hefei have much higher network radiation capabilities than network aggregation capabilities. However, other non-core cities and network edge cities have weak network radiation capabilities, and mainly accept network radiation from core cities. It enriches the research of urban networks based on real inter-?rm connections, and provides ideas for the wider regional study and the combination of econometric techniques and social network analysis. 展开更多
关键词 Urban networks INTERLOCKING network Model YANGTZE river DELTA China
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Use of Rough Sets Theory in Point Cluster and River Network Selection
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作者 Jia Qiu Ruisheng Wang Wenjing Li 《Journal of Geographic Information System》 2014年第3期209-219,共11页
In this paper, we applied the rough sets to the point cluster and river network selection. In order to meet the requirements of rough sets, first, we structuralize and quantify the spatial information of objects by co... In this paper, we applied the rough sets to the point cluster and river network selection. In order to meet the requirements of rough sets, first, we structuralize and quantify the spatial information of objects by convex hull, triangulated irregular network (TIN), Voronoi diagram, etc.;second, we manually assign decisional attributes to the information table according to conditional attributes. In doing so, the spatial information and attribute information are integrated together to evaluate the importance of points and rivers by rough sets theory. Finally, we select the point cluster and the river network in a progressive manner. The experimental results show that our method is valid and effective. In comparison with previous work, our method has the advantage to adaptively consider the spatial and attribute information at the same time without any a priori knowledge. 展开更多
关键词 ROUGH Sets THEORY Map GENERALIZATION POINT CLUSTER river network Progressive SELECTION
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International Freight Forwarding Services Network in the Yangtze River Delta, 2005–2015: Patterns and Mechanisms 被引量:4
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作者 LIANG Shuangbo CAO Youhui +3 位作者 WU Wei GAO Jinlong LIU Weichen ZHANG Weiyang 《Chinese Geographical Science》 SCIE CSCD 2019年第1期112-126,共15页
This study examined the spatio-temporal trajectories of the international freight forwarding service(IFFS) in the Yangtze River Delta(YRD) and explored the driving mechanisms of the service. Based on a bipartite netwo... This study examined the spatio-temporal trajectories of the international freight forwarding service(IFFS) in the Yangtze River Delta(YRD) and explored the driving mechanisms of the service. Based on a bipartite network projection from an IFFS firm-city data source, we mapped three IFFS networks in the YRD in 2005, 2010, and 2015. A range of statistical indicators were used to explore changes in the spatial patterns of the three networks. The underlying influence of marketization, globalization, decentralization, and integration was then explored. It was found that the connections between Shanghai and other nodal cities formed the backbones of these networks. The effects of a city's administrative level and provincial administrative borders were generally obvious. We found several specific spatial patterns associated with IFFS. For example, the four non-administrative centers of Ningbo, Suzhou, Lianyungang, and Nantong were the most connected cities and played the role of gateway cities. Furthermore, remarkable regional equalities were found regarding a city's IFFS network provision, with notable examples in the weakly connected areas of northern Jiangsu and southwestern Zhejiang. Finally, an analysis of the driving mechanisms demonstrated that IFFS network changes were highly sensitive to the influences of marketization and globalization, while regional integration played a lesser role in driving changes in IFFS networks. 展开更多
关键词 international FREIGHT FORWARDING service network pattern mechanism headquarters-branch method YANGTZE river DELTA
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Project of “Three Networks Greening” based on optimal allocation in the Yellow River Delta,China (Dongying section) 被引量:1
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作者 ZHAO Jun LIU Gao-huan +1 位作者 LIU Qing-sheng HUANG Chong 《Forestry Studies in China》 CAS 2010年第4期236-242,共7页
We have used the Yellow River Delta (Dongying section) as our study area to address the project of "Three Networks Greening" (TNG). With the use of GIS technology and from an ecological point of view, an optimal... We have used the Yellow River Delta (Dongying section) as our study area to address the project of "Three Networks Greening" (TNG). With the use of GIS technology and from an ecological point of view, an optimal allocation scheme of land resources is constructed and applied to guide the adjustment of land resources. Given this scheme, we have calculated that the area of land suitable for forest and shrubs without greening is 2256 km^2. Simultaneously, acting on the layout of the TNG project, afforestation site types are prepared and improved. Soil types, microrelief, salinity and underwater levels are combined as major classification factors and irrigation conditions as a reference to classify sites into eight types. In this way, land suitable for forest and grass is afforested given particular planting patterns. Finally, by overlaying this forestry site type map with the TNG plan map, some suggestions and strategies are proposed and used to direct the TNG project. An ecological oasis of the Yellow River Delta should be the result. 展开更多
关键词 land resources optimal allocation Three networks Greening site condition types Yellow river Delta
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基于河网水动力模型的水系连通性对水环境质量的影响分析研究 被引量:3
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作者 夏文文 王晨波 +3 位作者 邓宇 陈黎明 刘承磊 汤云高 《中国农村水利水电》 北大核心 2024年第3期96-104,共9页
平原河网地区地势平坦流速较缓,水体抗污染能力弱,改善水系连通性对水环境质量提升至关重要。以水系连通性较差的盛泽镇跃进联圩为研究对象,通过开展引调水试验,构建圩区河网水动力模型,探索圩区水利工作调度运行规则、河网水系连通方... 平原河网地区地势平坦流速较缓,水体抗污染能力弱,改善水系连通性对水环境质量提升至关重要。以水系连通性较差的盛泽镇跃进联圩为研究对象,通过开展引调水试验,构建圩区河网水动力模型,探索圩区水利工作调度运行规则、河网水系连通方法以及相应的水环境变化规律。研究以水龄作为水系连通性的一种时间尺度参量,建立了跃进联圩水动力-水质-水龄的河网水环境模型,模拟了5种引调水方案下,圩内水系连通性及水质改善情况,并构建了压力、状态与响应的引调水连通效果评估体系,实现了对水系连通性变化与水环境改善水平的定量分析。结果表明:从水体交换时长来看,研究区域主要河道水体交换时间在5天以内,水体连通性越好的河道,水龄越短;从水质指标变化来看,调水实验中圩内的水环境氨氮变化最为明显,对引调水响应度高,模拟结果显示水龄与氨氮浓度变化趋势基本一致,水体连通性越好,水龄越短,有利于氨氮的削减;从引调水方案来看,单一调度方式对圩内水系连通性改善能力有限,特别是在河网内水体流动性弱的区域,同时使得圩区内水体流动性差异增大,更容易造成河网内水系连通性以及水质的空间分布差异,形成局部的滞水区或死水区。因此,采用多源引水与多区域排水相配合的调度方式,可以加强水系连通性,改善水环境质量。 展开更多
关键词 平原河网 水系连通 水龄 效果评估
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分支河流体系沉积学工作框架与流程 被引量:3
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作者 张昌民 张祥辉 +4 位作者 王庆 冯文杰 李少华 易雪斐 Adrian JHARTLEY 《岩性油气藏》 CAS CSCD 北大核心 2024年第1期1-13,共13页
基于现有的研究成果和存在的问题,探讨了分支河流体系(DFS)研究中的关键科学问题、主要研究内容、研究方法和工作流程。研究结果表明:①DFS研究中最关键的3个科学问题是明确河网结构和河型演变规律、构建沉积标志和沉积模式、分析其形... 基于现有的研究成果和存在的问题,探讨了分支河流体系(DFS)研究中的关键科学问题、主要研究内容、研究方法和工作流程。研究结果表明:①DFS研究中最关键的3个科学问题是明确河网结构和河型演变规律、构建沉积标志和沉积模式、分析其形成和分布的控制因素。②DFS研究的主要内容包括建设形态沉积学数据库、现代沉积机理研究、分类研究、建立沉积模式、储层建模与储层预测等5个方面。③DFS研究中的关键技术包括基于遥感图像的形态数据采集、形成机理的水槽和模拟实验、河网重构、顶点位置预测与河道分汊点自动生成方法、储层建模知识库平台等。④DFS研究的基本工作流程是先建立形态沉积学数据库,搭建数据库软件平台,在此基础上选择具有代表性的DFS进行现代沉积解剖,然后综合现代沉积调查、露头解剖和模拟实验成果,形成分类体系,总结各类DFS的识别标志和沉积模式,分层次建立储层预测模型,形成沉积结构储层预测模型的建模软件平台,从而预测沉积体系中有利储层的分布。 展开更多
关键词 分支河流体系 河网重构 储层建模 水槽沉积模拟 数据采集 DFS形态沉积学数据库
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机器学习算法在降水和气温多模式集成中的应用 被引量:1
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作者 鞠琴 吴金雨 +5 位作者 王兴平 刘小妮 王逸夫 段远强 吴可馨 蒋晓蕾 《水资源保护》 EI CAS CSCD 北大核心 2024年第3期106-115,共10页
选取CMIP6中5种全球气候模式,利用算术平均、权重平均、多元线性回归、BP神经网络、长短期记忆(LSTM)神经网络和随机森林(RF)等6种多模式集成方法,基于黄河流域水源涵养区历史降水量和气温数据,评估不同集成方法的模拟效果,并选取模拟... 选取CMIP6中5种全球气候模式,利用算术平均、权重平均、多元线性回归、BP神经网络、长短期记忆(LSTM)神经网络和随机森林(RF)等6种多模式集成方法,基于黄河流域水源涵养区历史降水量和气温数据,评估不同集成方法的模拟效果,并选取模拟效果最好的多模式集成方法预估未来SSP1-2.6、SSP2-4.5和SSP5-8.53种情景下黄河流域水源涵养区的降水和气温变化趋势。结果表明:多模式集成能很好地再现基准期降水和气温变化,3种机器学习算法表现相对较好,其中LSTM神经网络最好;在未来3种情景下,多年平均降水量均有所增加,四季降水量变化各有差异;SSP1-2.6情景下年降水量峰值出现在各时段初期,SSP2-4.5和SSP5-8.5情景下的年降水量呈增长趋势,远期下降趋势较明显;3种情景下气温都呈上升趋势,但变化差异较大,增温幅度和速率由小到大为SSP1-2.6、SSP2-4.5、SSP5-8.5,秋季气温增幅最大,冬季最小;多模式集成方法对未来降水量和气温的预估存在较大的不确定性,均表现为中远期大于近期,降水量预估的不确定性比气温大,其中降水量秋冬季不确定性明显大于春夏季。 展开更多
关键词 CMIP6 全球气候模式 多模式集成 LSTM神经网络 黄河流域
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Application of Artificial Neural Networks in Order to Predict Mahabad River Discharge
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作者 Saman Mohammadi Maaroof Siosemarde 《Open Journal of Ecology》 2016年第7期427-434,共8页
Estimating of river discharge is one of the more important parameters in the water resources management. In recent years, due to increasing population, increased water consumption in industrial, agricultural and healt... Estimating of river discharge is one of the more important parameters in the water resources management. In recent years, due to increasing population, increased water consumption in industrial, agricultural and health sections, thus water shortge becomes a global problem. Accurate estimation of the river discharge is one of the most important parameters in surface water resources management, especially in order to determine appropriate values in flood, drought, drinking, agricultural and industral topics. The case study in this research is Mahabad River that is located in west Azarbaijan province in west north of Iran. In this study, we used 70%, 15% and 15% data in order to train, validate and test, respectively. In this study, data of Kawtar and Baitas stations were used in order to determine Mahabad River discharge. In each ststion, several different networks were prepared using NeuroSolutions V.6.0 software. The neural models included Multilayer Perceptron (MLP), Generalized Feed Forward, Jordan/Elman, Radial Basis Functions (RBF) and Principle Component Analysis (PCA), and different transfer functions included Tanh, Sigmoid, Linear Tanh, Linear Sigmoid and the number of hidden layers of.The different number of nodesin layers with different learning algorithms (Momentum, Levenberg Marquardt, Quickprop, DeltaBarDelta, Conjugate Gradient) and different networks were compared. The results showed the artificial neural networks. They predicted the river discharge with 10.67 and 0.94 (m<sup>3</sup>/s)<sup>2</sup> and the high value of correlation coefficient with 0.88 and 0.75 for Kawtar and Baitas stations respectivly. 展开更多
关键词 Artificial Neural networks DISCHARGE ESTIMATE Mahabad NeuroSolutions Software river
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国家水网构建与生态安全保障辩证关系探析 被引量:1
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作者 王建华 胡鹏 《中国水利》 2024年第17期48-51,61,共5页
国家水网建设和水生态安全保障是当前和今后一个时期水利行业的核心工作,准确认识两者的辩证关系,对于促进水利高质量发展、为中国式现代化提供高标准水安全保障具有重要意义。从国家水网建设与我国生态安全总体格局、北方生态屏障区保... 国家水网建设和水生态安全保障是当前和今后一个时期水利行业的核心工作,准确认识两者的辩证关系,对于促进水利高质量发展、为中国式现代化提供高标准水安全保障具有重要意义。从国家水网建设与我国生态安全总体格局、北方生态屏障区保护修复、缺水地区河湖生态环境复苏、地下水超采区治理恢复、河湖水质改善、重要湿地及其生物多样性保护等六个方面的关系阐述了国家水网对于保障国家生态安全的重要作用。科学解析了国家水网规划、建设与运行对生态安全保障可能带来的影响,提出协同推进国家水网建设与生态安全保障的措施建议:优化国家生态安全保障整体格局,明晰重点区域生态安全保障水资源需求;在国家水网框架内,开展国家水生态网整体规划与建设;维护和发挥地下水应急储备水源功能,构建立体国家水网;加强水网内部源头减排与属地治理,建设清洁水网;发挥国家战略储备水源区作用,降低集中调水对长江流域的影响;加强水工程全生命期绿色技术研发与应用。 展开更多
关键词 国家水网 生态安全 河湖生态复苏 水工程生态影响
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