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Penalty model for delay of bidding section construction period in South-to-North Water Diversion Eastern Route Project from perspective of programs 被引量:2
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作者 Jing-chun FENG Ya-fang REN +2 位作者 Zhong-nan DUAN Zhan-jun LIU Hai-yang LI 《Water Science and Engineering》 EI CAS 2012年第3期350-360,共11页
According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculatio... According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculation of penalty for delay of the bidding section construction period with the critical path method, we studied the effects of contractor-induced delay of the bidding section construction period in detail, including the effects on the construction period of the bidding section itself, the earliest start times of the next bidding section and other subsequent bidding sections, and the construction period of the program, and then constructed a penalty model for delay of the bidding section construction period from the perspective of programs. Using the penalty model, we conducted a practical analysis of penalty for delay of the construction period of the Baoying station program in the South-to-North Water Diversion Project. The model can help determine the amount of penalty for delay of the construction period in bidding sections scientifically and reasonably, 展开更多
关键词 program establishment program management bidding section construction period critical path method (CPM) penaly model south-to-north water diversion project
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Spatio-temporal distribution of phytoplankton in the Danjiangkou Reservoir, a water source area for the South-to-North Water Diversion Project (Middle Route), China 被引量:12
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作者 殷大聪 郑凌凌 宋立荣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第3期531-540,共10页
One of the water source areas of the South-to-North Water Diversion Project is the Danjiangkou Reservoir (DJKR). To understand seasonal variation in phytoplankton composition, abundance and distribution in the DJKR ... One of the water source areas of the South-to-North Water Diversion Project is the Danjiangkou Reservoir (DJKR). To understand seasonal variation in phytoplankton composition, abundance and distribution in the DJKR area before water diversion, as well as to estimate potential risks of water quality after water diversion, we conducted an investigation on phytoplankton in the DJKR from August 2008 to May 2009. The investigation included 10 sampling sites, each with four depths of 0.5, 5, 10, and 20 m. In this study, 117 taxa belonging to 76 genera were identified, consisting of diatoms (39 taxa), green algae (47 taxa), blue-green algae (19 taxa), and others (12 taxa). Annual average phytoplankton abundance was 2.01×10^6 ind./L, and the highest value was 14.72 ×10^6 ind/L (at site 3 in August 2008). Phytoplankton abundance in front of the Danjiangkou Dam (DJKD) was higher than that of the Danjiang Reservoir Basin. Phytoplankton distribution showed a vertical declining trend from 0.5 m to 20 m at most sites in August 2008 (especially at sites of 1, 2, 4 and 10), but no distinct pattern in other sampling months. In December 2008 and March 2009, Stephanodiseus sp. was the most abundant species, amounting to 55.23% and 72.34%, respectively. We propose that high abundance ofStephanodiscus sp. may have contributed greatly to the frequent occurrence of Stephanodiscus sp. blooms in middle-low reaches of the Hanjiang River during the early spring of 2009. In comparison with previous studies conducted from 1992 to 2006, annual average phytoplankton density, green algae and blue-green algae species, as well as major nutrient concentrations increased, while phytoplankton diversity indices declined. This indicates a gradual decline in water quality. More research should be conducted and countermeasures taken to prevent further deterioration of water quality in the DJKR. 展开更多
关键词 Danjiangkou Reservoir PHYTOPLANKTON south-to-north water diversion project EUTROPHICATION
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Critical chain construction with multi-resource constraints based on portfolio technology in South-to-North Water Diversion Project 被引量:3
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作者 Jing-chun FENG Lei LI +4 位作者 Nan YANG Yu-zhen HONG Min PANG Xiong YAO Li-cheng WANG 《Water Science and Engineering》 EI CAS 2011年第2期225-236,共12页
Recently, the critical chain study has become a hot issue in the project management research field. The construction of the critical chain with multi-resource constraints is a new research subject. According to the sy... Recently, the critical chain study has become a hot issue in the project management research field. The construction of the critical chain with multi-resource constraints is a new research subject. According to the system analysis theory and project portfolio theory, this paper discusses the creation of project portfolios based on the similarity principle and gives the definition of priority in multi-resource allocation based on quantitative analysis. A model with multi-resource constraints, which can be applied to the critical chain construction of the A-bid section in the South-to-North Water Diversion Project, was proposed. Contrast analysis with the comprehensive treatment construction method and aggressive treatment construction method was carried out. This paper also makes suggestions for further research directions and subjects, which will be useful in improving the theories in relevant research fields. 展开更多
关键词 multi-resource constraints south-to-north water diversion project project portfolio critical chain
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Land Cover Changes and Drivers in the Water Source Area of the Middle Route of the South-to-North Water Diversion Project in China from 2000 to 2015 被引量:4
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作者 GAO Wenwen ZENG Yuan +2 位作者 ZHAO Dan WU Bingfang REN Zhiyuan 《Chinese Geographical Science》 SCIE CSCD 2020年第1期115-126,共12页
The Middle Route of the South-to-North Water Diversion Project(MR-SNWDP)in China,with construction beginning in 2003,diverts water from Danjiangkou Reservoir to North China for residential,agriculture and industrial u... The Middle Route of the South-to-North Water Diversion Project(MR-SNWDP)in China,with construction beginning in 2003,diverts water from Danjiangkou Reservoir to North China for residential,agriculture and industrial use.The water source area of the MR-SNWDP is the region that is most sensitive to and most affected by the construction of this water diversion project.In this study,we used Landsat Thematic Mapper(TM)and HJ-1 A/B images from 2000 to 2015 by an object-based approach with a hierarchical classification method for mapping land cover in the water source area.The changes in land cover were illuminated by transfer matrixes,single dynamic degree,slope zones and fractional vegetation cover(FVC).The results indicated that the area of cropland decreased by 31%and was replaced mainly by shrub over the past 15 years,whereas forest and settlements showed continuous increases of 29.2% and 77.7%,respectively.The changes in cropland were obvious in all slope zones and decreased most remarkably(–43.8%)in the slope zone above 25°.Compared to the FVC of forest and shrub,significant improvement was exhibited in the FVC of grassland,with a growth rate of 16.6%.We concluded that local policies,including economic development,water conservation and immigration resulting from the construction of the MR-SNWDP,were the main drivers of land cover changes;notably,they stimulated the substantial and rapid expansion of settlements,doubled the wetlands and drove the transformation from cropland to settlements in immigration areas. 展开更多
关键词 remote sensing land cover change object-based classification Middle Route of the south-to-north water diversion project(MR-SNWDP) China
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Reliability model of organization management chain of South-to-North Water Diversion Project during construction period 被引量:3
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作者 Feng Jingchun Zhou Yang +2 位作者 Hong Yuzhen Zhao Shixin Ren Xiaoqiang 《Water Science and Engineering》 EI CAS 2008年第4期107-113,共7页
In order to analyze the indispensability of the organization management chain of the South-to-North Water Diversion Project (SNWDP), two basic forms (series connection state and mixed state of both series connectio... In order to analyze the indispensability of the organization management chain of the South-to-North Water Diversion Project (SNWDP), two basic forms (series connection state and mixed state of both series connection and parallel connection) of the organization management chain can be abstracted. The indispensability of each form has been studied and is described in this paper. Through analysis of the reliability of the two basic forms, reliability models of the organization management chain in the series connection state and the mixed state of both series connection and parallel connection have been set up. 展开更多
关键词 south-to-north water diversion project reliability model management chain parallel connection series connection
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Wet-Dry Runoff Correlation in Western Route of South-to-North Water Diversion Project,China 被引量:2
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作者 HUANG Xiao-rong ZHAO Jing-wei YANG Peng-peng 《Journal of Mountain Science》 SCIE CSCD 2015年第3期592-603,共12页
The Western Route of the South-to-North Water Diversion Project is an important trans-basin diversion project to transfer water from the upstream Yangtze River and its tributaries (water-exporting area), to the upst... The Western Route of the South-to-North Water Diversion Project is an important trans-basin diversion project to transfer water from the upstream Yangtze River and its tributaries (water-exporting area), to the upstream of the Yellow River (water- importing area). The long-term hydrologieal data from 14 stream gauging stations in the Western Route area and techniques including the pre-whitening approach, non-parametric test, Bayes, law, variance analysis extrapolation, and Wavelet Analysis are applied to identify the streamflow eharacteristics and trends, streamflow time series cross-correlations, wetness-dryness encountering probability, and periodicities that occurred over the last 50 years. The results show that the water-exporting area, water- importing area, and the streteh downstream of the water-exporting have synehronization in high-low flow relationship, whereas they display non- synchronization in long-term evolution. This corresponds to the complicated and variable climate of the plateau region. There is no obvious increasing or decreasing trend in runoff at any gauging station. The best hydrological eompensation probability for rivers where water is diverted is about 25% to lO%, and those rivers influenced significantly by diversion are the Jinsha and Yalong rivers. Proper planning and design of compensation reservoirs for the water-exporting area and stretch downstream of the water- exporting area can increase the hydrological compensation possibility from water-exporting area to the water-importing area, and reduce the impact on the stretch of river downstream of the water- exporting area. 展开更多
关键词 south-to-north water diversion project Yangtze River Streamflow Encounter probability Correlation coefficient Cycle Hydrologicalcompensation
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IMPACTS OF THE SOUTH-TO-NORTH WATER DIVERSION PROJECTS (MIDDLE ROUTE)ON THE WATER ENVIRONMENT OF THE MIDDLE AND LOWER REACHES OF THE HANJIANG RIVER
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作者 FAN Bei-Lin, WAN Jian-Rong, ZHANG Jie and LIN Qiu-Sheng (Yangtze River Scientific Research Institute,River Research Deparment, Wuhan 430010,China) 《水生生物学报》 CAS CSCD 北大核心 2006年第6期643-646,共4页
In this paper, according to the rule of unbalanced sediment transport and the analysis of field data, different water diversion schemes were theoretically studied, including the erosion and sedimentation trend as well... In this paper, according to the rule of unbalanced sediment transport and the analysis of field data, different water diversion schemes were theoretically studied, including the erosion and sedimentation trend as well as their impacts on the environment of the middle and lower reaches of the Hanjiang River. The results showed that the 95×10 8m 3 water diversion scheme will cause less erosion and water level decrease than the 15×10 8m 3 water diversion scheme. Using a water diversion scheme of 95×10 8m 3, the decrease of water quantity can impact the river hydrodynamic regime substantially and the environments of the middle and lower reaches of the Hanjiang River will be greatly affected. It is therefore necessary to develop new water resources or build projects to meet the need of the environment and the needs for navigation. 展开更多
关键词 south-to-north water diversion project River regime water environment Mathematical model
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Water-saving potential evaluation of water-receiving regions in Shandong province on the East Route of the South-to-North Water Transfer Project of China
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作者 YIN Xiao-lin GAO Yuan-yuan +1 位作者 WU Hai-ping ZHAO Xue-ming 《Journal of Groundwater Science and Engineering》 2020年第3期287-297,共11页
Taking 13 water-receiving areas on the East Route of the South-to-North Water Diversion Project(ERSNWDP)in Shandong Province as the study area,and comparing it with Jiangsu Province on the ERSNWDP and the Middle Route... Taking 13 water-receiving areas on the East Route of the South-to-North Water Diversion Project(ERSNWDP)in Shandong Province as the study area,and comparing it with Jiangsu Province on the ERSNWDP and the Middle Route of the South-to-North(MRSNWDP),the current water-saving potential of the water-receiving areas within the municipalities of Shandong was analyzed.Different water-saving scenarios were constructed and analyzed with key water-saving indexes in various industries.These indexes include the effective utilization coefficient of farmland irrigation water,total water consumption of industrial sectors with an added value of over 10000 RMB,average leakage rate of the urban public water supply pipe network and the penetration rate of water-saving appliances.Based on the scenarios,comprehensive water-saving potential of the 13 water-receiving area cities was calculated.The results show that the water-saving potential of the study area is at a relative high level.However,some cities still have a certain amount of water-saving potential for agriculture and industry to be elevated.Under the recommended water-saving scenario,the water-saving potential is 1.134 billion m3,accounting for 5.33%of the current total water consumption,of which 460 million m3 is in agriculture,600 million m3 in industry,is and 74.20 million m3 in urban domestic sector.Comprehensive water-saving measures for the study area were proposed from the aspects of agricultural,industrial and domestic water uses.Agricultural and industrial water saving are more significant.The major cities for agricultural water saving include Jining City,Heze City,Weifang City and Jinan City;the focus cities of industrial water saving mainly include Weihai City,Jining City and Qingdao City and etc.;the key water-saving areas for urban use mainly include Zaozhuang City,Jining City and Heze City. 展开更多
关键词 East Route of south-to-north water diversion project shandong water receiving area water-saving level water-saving potential
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Critical discharge at Datong for controlling operation of South-to-North Water Transfer Project in dry seasons 被引量:3
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作者 Wang Yigang Huang Huiming Li Xi 《Water Science and Engineering》 EI CAS 2008年第2期47-58,共12页
Previous research shows that there is a strong correlation between saltwater intrusion in the Yangtze Estuary and discharge at Datong. In the near future, the discharge of the Yangtze River during dry seasons will dec... Previous research shows that there is a strong correlation between saltwater intrusion in the Yangtze Estuary and discharge at Datong. In the near future, the discharge of the Yangtze River during dry seasons will decrease due to the construction and operation of large water diversion projects, including the South-to-North Water Transfer Project, which will further exacerbate saltwater intrusion in the estuary. In this paper, a nested 1D river network model and a 2D saltwater numerical model are used to associate saltwater intrusion in the Yangtze Estuary with different values of discharge at Datong. It is concluded that 13 000 m3/s is the critical discharge at Datong for preventing saltwater intrusion and controlling the volume of water transferred by the South-to-North Water Transfer Project. Furthermore, based on the analysis of river discharge from Datong to Xuliujing and in consideration of the influence of all of the water diversion projects, operation schemes are proposed for the Eastern Route of the South-to-North Water Transfer Project for different hydrological years. 展开更多
关键词 saltwater intrusion critical discharge at Datong water diversion the south-to-north water Transfer project
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Water diversion and agricultural production:Evidence from China 被引量:1
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作者 YANG Rui XU Hang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第4期1244-1257,共14页
Water diversion can alleviate water shortages caused by the uneven distribution of water resources.China’s Southto-North Water Diversion Project(SNWD)is the largest water diversion project worldwide.Based on the pref... Water diversion can alleviate water shortages caused by the uneven distribution of water resources.China’s Southto-North Water Diversion Project(SNWD)is the largest water diversion project worldwide.Based on the prefecturelevel data of China’s Huang-Huai-Hai Plain from 2000 to 2020,this study employs an empirical strategy of Differencesin-Differences(DID)to analyze the impact of SNWD on agricultural production.The results show that SNWD has significantly increased agricultural production,measured by the agricultural value added.The estimated results of the benchmark model remain robust when the contemporaneous policy is addressed,an alternative outcome is used,subsamples are estimated,and alternative estimation techniques are employed.This study argues that the potential impact mechanism may be that SNWD significantly increases the acreage for cash crops but reduces that for grain crops.Heterogeneity analysis shows that in prefectures with high temperature or land potential,SNWD’s impact on agricultural value added is relatively low.In contrast,in areas with prolonged sunshine or high slopes,SNWD’s impact on agricultural value added is relatively large.Given the low added value of grain crops,the government should consider strengthening food security by subsidizing water supply to sustain grain production. 展开更多
关键词 south-to-north water diversion project agricultural production Differences-in-Differences China
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On conservation and development of architecture and environment in the construction of large-scale national infrastructure——Exemplified by the Jiangsu Section of the Eastern Route South-to-North Water Diversion Project 被引量:1
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作者 DUAN Jin ,LUO JianLi,WANG XingPing,TANG Jun&YU Gang School of Architecture,Southeast University,Nanjing 210096,China 《Science China(Technological Sciences)》 SCIE EI CAS 2009年第12期3613-3625,共13页
The water-diverting route project’s characteristics,natural landscapes,and histories and humanism of the Jiangsu Section of the Eastern Route South-to-North Water Diversion Project were systemically analyzed through ... The water-diverting route project’s characteristics,natural landscapes,and histories and humanism of the Jiangsu Section of the Eastern Route South-to-North Water Diversion Project were systemically analyzed through proposing and studying the canal culture routes,the water resources heritage corridors,the landscape and recreation corridors,and the town economic corridors.The station areas along the water-diverting route were scientifically zoned and graded through quantitative and qualitative synthetic methods.Both planning compendiums and construction controlling methods were proposed based on the project grades of points,lines,and areas.Conservation and development of architecture and environment in the large-scale national infrastructure construction were explored systemically.Theories and methods of developing harmonious water-supplying functions,ecological functions,landscape effects,and cultural effects of large-scale water resources were examined. 展开更多
关键词 Jiangsu section of Eastern Route south-to-north water diversion project CANAL culture routes water resources heritage CORRIDORS landscape and RECREATION CORRIDORS town economic CORRIDORS synthetical ZONING and grading
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Application of SEDEA to evaluation of degree of harmony between water resources and economic development 被引量:1
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作者 Jun MA Chui-yong ZHENG 《Water Science and Engineering》 EI CAS 2011年第1期110-120,共11页
This paper introduces the method of data envelopment analysis (DEA) for evaluation of the degree of harmony between water resources and economic development of the water conservancy area of China's South-to-North W... This paper introduces the method of data envelopment analysis (DEA) for evaluation of the degree of harmony between water resources and economic development of the water conservancy area of China's South-to-North Water Diversion Project (SNWDP). For this evaluation, a super-efficiency DEA (SEDEA) model was developed based on the super-efficiency method. To verify the applicability of the SEDEA model, both the SEDEA model and a normal-efficiency DEA (NEDEA) model were used to evaluate the degree of harmony between water resources and economic development of typical cities in the SNWDP water conservancy area. The results show that the SEDEA model ranks the degree of harmony of typical cities more efficiently than the NEDEA model, and thus can better evaluate the degree of harmony between water resources and economic development of different cities than the NEDEA model. Furthermore, the SEDEA model can be applied as an operational research tool in regional water resources management. 展开更多
关键词 degree of harmony super-efficiency DEA model water conservancy area south-to-north water diversion project
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引江济淮工程(河南段)水资源调配系统设计与开发 被引量:1
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作者 李赫 刘进翰 +3 位作者 左其亭 甘容 王辉 冯跃华 《南水北调与水利科技(中英文)》 CAS CSCD 北大核心 2024年第1期186-195,共10页
为强化引江济淮工程(河南段)水资源统一调配,基于Spring Boot和Vue前后端分离开发的模式,利用天地图API、WebGL、Echarts等技术设计研发引江济淮工程(河南段)水资源调配系统。从设计思路、功能界面、关键技术3个角度论述系统设计思路和... 为强化引江济淮工程(河南段)水资源统一调配,基于Spring Boot和Vue前后端分离开发的模式,利用天地图API、WebGL、Echarts等技术设计研发引江济淮工程(河南段)水资源调配系统。从设计思路、功能界面、关键技术3个角度论述系统设计思路和实现过程,从而实现地理信息服务、供需水预测、水资源优化配置、水资源优化调度等功能,实现水量分配可视化、运行调度智能化和跨流域调水管控一体化。系统测试结果表明:引江济淮工程(河南段)水资源调配系统的建立提高了受水区水资源精细化管理的水平,解决了引江济淮工程(河南段)跨流域调水的配置难题,为受水区水资源高效利用提供有效的技术支撑。 展开更多
关键词 引江济淮工程(河南段) 水资源调配系统 Spring Boot框架 Vue框架 前后端分离开发模式 水资源和谐配置
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引江补汉工程丹江口下游近坝段枯水期通航水位恢复试验研究
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作者 朱勇辉 郭小虎 +2 位作者 李凌云 王彦君 张丹 《长江科学院院报》 CSCD 北大核心 2024年第10期6-13,共8页
引江补汉工程补水口位于丹江口大坝下游安乐河出口约5 km处,且补水量与调水量基本一致,工程对航道的影响主要体现在减水段,为恢复枯水期通航水位需要开展航道综合治理。利用河工模型试验论证了综合治理方案的效果,并对方案进行了优化及... 引江补汉工程补水口位于丹江口大坝下游安乐河出口约5 km处,且补水量与调水量基本一致,工程对航道的影响主要体现在减水段,为恢复枯水期通航水位需要开展航道综合治理。利用河工模型试验论证了综合治理方案的效果,并对方案进行了优化及进一步论证。结果表明,减水-补水212 m 3/s方案尾门水位分别为86.47、85.90 m条件下,引航道口—黄家港段水位下降,黄家港以下水位保持不变,其中引航道口水位下降幅度最大,分别下降0.08、0.19 m;综合治理方案1实施后引航道口水位下降均为0.02 m,减水段的水位仍未恢复至调水前的水平,主因是从安乐河口补水的水流并未能进入到左侧主航道内;基于试验研究结果,建议对综合治理方案进行优化,在沧浪洲出水口下沿布置2道护底带;通过试验论证了护底带的4个高程,建议护底带高程为85.5 m,并对护底带高程进一步细化论证;优化后的方案可使引航道口至黄家港段的水位略超过调水前的水平,其中引航道口处最大水位抬高0.06 m。 展开更多
关键词 引江补汉工程 近坝段 枯水期 通航水位 河工模型试验 恢复试验 航道综合治理
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引江济淮工程(河南段)多目标水量优化调度 被引量:1
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作者 宋志红 刘渊 +5 位作者 江生金 蒋恒 方俊 陈钊 王永强 王冬 《南水北调与水利科技(中英文)》 CAS CSCD 北大核心 2024年第1期39-47,共9页
引江济淮工程(河南段)涉及河道、闸泵、管道和调蓄水库,约束条件复杂,常规的优化调度算法难以搜索可行解,求解效率低。选用受水区缺水率平均值最小、泵站总抽水量最小和受水区缺水率标准差最小作为目标函数,从供水保障、供水成本和公平... 引江济淮工程(河南段)涉及河道、闸泵、管道和调蓄水库,约束条件复杂,常规的优化调度算法难以搜索可行解,求解效率低。选用受水区缺水率平均值最小、泵站总抽水量最小和受水区缺水率标准差最小作为目标函数,从供水保障、供水成本和公平性角度构建多目标水量优化调度模型。基于可行搜索思路,结合逆序演算和顺序演算过程对约束条件进行处理,引入决策系数,通过映射关系使搜索空间保持在可行域中,结合多目标非支配排序遗传算法(non-dominated sorting genetic algorithms,NSGA-II)进行求解,得到Pareto最优解集,并采用熵权法进行方案优选。结果表明,基于可行搜索的NSGA-II算法能够有效求解复杂调度系统的多目标优化问题,综合考虑多个目标的最优方案相对单目标方案更加合理,结果可为引江济淮工程(河南段)运行管理提供决策支撑。 展开更多
关键词 引江济淮工程(河南段) 可行搜索 多目标 水量优化调度 NSGA-II算法
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高海拔季节冻土区完全融化期土壤水分特征曲线适用性
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作者 张海生 翁白莎 +3 位作者 严登华 栾清华 李文文 邓彬 《南水北调与水利科技(中英文)》 CAS CSCD 北大核心 2024年第2期247-257,358,共12页
以怒江源区那曲流域为例,基于4个试验场完全融化期(6—9月)的土壤体积含水量(0.15~0.51 cm^(3)/cm^(3))和土壤基质势数据(0~200 kPa)实测数据,选择Van Genuchten(VG)、Brooks-Corey(BC)和Campbell 3个模型进行拟合,以均方根误差ERMS和... 以怒江源区那曲流域为例,基于4个试验场完全融化期(6—9月)的土壤体积含水量(0.15~0.51 cm^(3)/cm^(3))和土壤基质势数据(0~200 kPa)实测数据,选择Van Genuchten(VG)、Brooks-Corey(BC)和Campbell 3个模型进行拟合,以均方根误差ERMS和决定系数R2为评价指标,分析3个模型对高海拔季节冻土区不同土层和不同土壤质地的适用性。结果表明:从整体上看,VG模型(平均R2为0.992,平均ERMS为0.006 cm^(3)/cm^(3))的拟合效果优于BC模型(平均R2为0.972,平均ERMS为0.019 cm^(3)/cm/3)和Campbell模型(平均R2为0.984,平均ERMS为0.014 cm^(3)/cm^(3));但是在不同土层和不同土壤质地情况下模型的适用性有所区别,VG模型更适用于壤土和壤质砂土(平均R2为0.987,平均ERMS为0.008 cm^(3)/cm^(3))以及土壤深层(10~35 cm土层,平均R2为0.990,平均ERMS为0.007 cm^(3)/cm^(3)),Campbell模型更适用于砂质壤土(平均R2为0.985,平均ERMS为0.009 cm^(3)/cm^(3))以及土壤表层(5 cm土层,平均R2为0.993,平均ERMS为0.006 cm^(3)/cm^(3)),BC模型在不同条件下都不是最优模型;参数θr取值大小会显著影响土壤水分特征曲线的形状。本研究可为深入研究高海拔季节冻土区的土壤水分运动特性以及中华水塔区的水源涵养作用提供支持。 展开更多
关键词 土壤水分特征曲线 模型优选 土壤质地 Van Genuchten模型 那曲流域
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调水工程建设期安全-进度-投资系统风险分析——以引江济淮工程(河南段)为例
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作者 何山 王辉 +4 位作者 程卫帅 刘渊 范嘉懿 王永强 桑连海 《南水北调与水利科技(中英文)》 CAS CSCD 北大核心 2024年第2期348-358,共11页
以引江济淮工程(河南段)为例,在确定安全-进度-投资系统风险评价指标体系的基础上,基于层次分析-模糊综合评价方法分析安全、进度、投资的单项风险;在考虑工程建设期安全、进度、投资的相互影响后,基于改进的综合风险评价方法分析安全-... 以引江济淮工程(河南段)为例,在确定安全-进度-投资系统风险评价指标体系的基础上,基于层次分析-模糊综合评价方法分析安全、进度、投资的单项风险;在考虑工程建设期安全、进度、投资的相互影响后,基于改进的综合风险评价方法分析安全-进度-投资系统风险。结果表明:当分析单项风险时,安全、进度和投资风险的评价结果均为一般风险;当分析系统风险时,得到安全风险>进度风险>投资风险;进一步分析指标体系中的准则层和指标层,安全风险的现场风险中施工技术方案风险排序第一,是后续风险管控的重点。本研究为提高工程建设期安全-进度-投资系统风险的可靠性、降低风险事件的发生提出了理论和技术参考。 展开更多
关键词 施工风险 改进综合风险评价法 安全-进度-投资系统风险 调水工程 引江济淮工程(河南段)
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调水调沙影响下黄河山东段鱼类群落格局及多样性
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作者 丛旭日 李秀启 +3 位作者 董贯仓 孙鲁峰 客涵 任一平 《水生生物学报》 CAS CSCD 北大核心 2024年第6期889-897,I0001-I0003,共12页
文章于2019—2021年调水调沙前后利用多种网具对黄河山东段4个站位开展鱼类资源调查,研究了黄河山东段鱼类群落的种类组成、生态类型、优势种、生物多样性及环境影响因子等。结果表明,山东段共采集鱼类59种,隶属于10目20科,调水前优势... 文章于2019—2021年调水调沙前后利用多种网具对黄河山东段4个站位开展鱼类资源调查,研究了黄河山东段鱼类群落的种类组成、生态类型、优势种、生物多样性及环境影响因子等。结果表明,山东段共采集鱼类59种,隶属于10目20科,调水前优势种为鲫(Carassius auratus)、鳊(Parabramis pekinensis)、鲤(Cyprinus carpio)、赤眼鳟(Squaliobarbus curriculus)、翘嘴鲌(Culter alburnus)、草鱼(Ctenopharyngodon idellus)、鲻(Mugil cephalus)、鮻(Liza haematocheilus),调水后优势种为鲫、鳊、鲤、赤眼鳟。多样性指数方面ShannonWiener指数、丰富度指数差异较显著(0.01<P<0.05),均匀度指数差异不显著(P>0.05)。聚类分析表明,调水调沙前后黄河山东段鱼类群落结构在相似水平为45%时可以划分为2组,调水调沙后东阿断面(AH2)与其他断面相比具有较强的差异性;相似水平为60%时可以划分为4组,分别为A组群(AH3、BH3和BH2)、B组群(AH1和BH1)、C组群(AH4和BH4)、D组群(AH2)。SIMPER分析显示,A组群平均相似率为60.66%,特征种包括鳊、翘嘴鲌、赤眼鳟、鮻、似鳊(Pseudobrama simoni)、鲢(Hypophthalmichthys molitrix),B组群平均相似率为66.38%,特征种包括鳊、鲫、鲇(Silurus asotus)、鲤、(Hemiculter leucisculus),C组群平均相似率为68.48%,特征种包括鲤、鲫、翘嘴鲌、鳊、鮻。RDA分析表明径流量、总磷是影响群落结构的主要因子。基于以上结果,研究对比黄河各河段鱼类群落结构特征,分析调水调沙对黄河山东段鱼类群落格局及多样性的影响,发现庞口湾作为鱼类栖息地的重要性并提出保护建议。研究可为黄河山东段渔业资源保护和可持续发展提供理论依据和技术支撑。 展开更多
关键词 黄河山东段 调水调沙 鱼类群落 多样性 环境因子
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基于改进层次分析法的征迁实施效果评价
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作者 刘晓岭 宋涛 王海峰 《水科学与工程技术》 2024年第5期1-3,共3页
基于改进层次分析法(Improved Analytic Hieratchy Process,IAHP),对南水北调中线工程豫北段征迁工作的实施效果进行模拟评价。IAHP法有效避免了层次分析法(Analytic Hierarchy Process,AHP)中难以准确对元素间相对重要程度进行定量判断... 基于改进层次分析法(Improved Analytic Hieratchy Process,IAHP),对南水北调中线工程豫北段征迁工作的实施效果进行模拟评价。IAHP法有效避免了层次分析法(Analytic Hierarchy Process,AHP)中难以准确对元素间相对重要程度进行定量判断,IAHP法创建的判断矩阵具有自调节性,满足判断矩阵一致性的要求,可以省去AHP法一致性检验的过程,降低了参与者对指标间进行比较的繁杂程度,同时后期计算量也大为降低。从评价结果看,当评价指标和指标体系构建合理时,IAHP法能很好地替代AHP法。 展开更多
关键词 改进层次分析法 征迁 实施效果 南水北调 豫北段
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基于云模型的引调水工程突发水污染事件风险评价——以引江济淮工程(河南段)为例
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作者 陈述 王辉 +3 位作者 张泰赫 范嘉懿 刘爽 王静 《长江科学院院报》 CSCD 北大核心 2024年第10期48-55,62,共9页
开展引调水工程突发水污染事件风险评价,降低突发水污染事件的危险性和危害程度,对发挥引调水工程综合效益、提高区域供水安全保障能力等具有十分重要的意义。基于驱动力-压力-状态-影响-响应(DPSIR)模型,构建能反映风险源特征和风险受... 开展引调水工程突发水污染事件风险评价,降低突发水污染事件的危险性和危害程度,对发挥引调水工程综合效益、提高区域供水安全保障能力等具有十分重要的意义。基于驱动力-压力-状态-影响-响应(DPSIR)模型,构建能反映风险源特征和风险受体特性的引调水工程突发水污染事件风险评价指标体系,提出基于云模型的引调水工程突发水污染事件风险等级评价方法,定量评价引江济淮工程(河南段)突发水污染事件风险。结果表明,引江济淮工程(河南段)突发水污染事件风险较低,有5个评价河段的风险等级均为一般(Ⅳ级),2个评价河段的风险等级为重大(Ⅱ级),与从风险源危险性、风险受体易损性、风险控制有效性等3个方面开展的定性评价结果一致。研究结果为合理评价引调水工程突发水污染事件风险提供了新的方法,为引江济淮工程(河南段)突发水污染事件风险管理提供了依据。 展开更多
关键词 突发水污染事件 引调水工程 云模型 风险评价 引江济淮工程(河南段)
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