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Demonstration of Center Pivot Uniformity Evaluation and Retrofit to Improve Water Use Efficiency
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作者 Younsuk Dong Lyndon Kelley Eric Anderson 《Journal of Water Resource and Protection》 CAS 2023年第3期71-84,共14页
Agricultural irrigation is a primary user for freshwater withdrawal. Irrigation plays an important role in crop production, as it provides the benefit of reducing the effects of prolonged dryness and erratic precipita... Agricultural irrigation is a primary user for freshwater withdrawal. Irrigation plays an important role in crop production, as it provides the benefit of reducing the effects of prolonged dryness and erratic precipitation. Center pivot irrigation system is the most common irrigation system in agriculture. As the center pivot irrigation system ages, the system could develop a leaking joint, clogged sprinklers, and physical damage. This can cause areas of non-uniformity that can lead to under- or over-irrigated in some areas of the land, resulting in excess energy use and cost, wasting resources, and environmental impacts. Thus, it is important to evaluate the performance of a center pivot irrigation system regularly to maximize return on investments and minimize wasting resources. This study focuses on evaluating the impacts and benefits of improved center pivot irrigation distribution uniformity by performing distribution uniformity evaluations pre- and post-retrofit. This study also focused on demonstrating an unmanned aerial vehicle (UAV) to assess the performance of the center pivot irrigation system in two irrigated farmlands. The Coefficient of Uniformity (CU), Distribution Uniformity (DU), and Scheduling Coefficient (SC) were calculated based on the catch can test data. The values were utilized to evaluate water and energy savings from the improved coefficients. The team has found that replacing sprinkler packages increased the CU from 78 to 89 and the DU from 77 to 82, and reduced the SC from 1.3 to 1.2 in Field A. In Field B, replacing sprinkler packages increased the CU from 73 to 91 and the DU from 62 to 84 and reduced the SC from 1.6 to 1.2. The estimated water savings in Field A due to the reduced scheduling coefficient was approximately 151,000 liters/hectare/year, with consideration of the corn and soybean rotation field in Michigan. The estimated water savings in Field B was 608,000 liters/hectare/year. The data from this demonstration study showed the value of distribution uniformity evaluation and retrofit of irrigation systems. This information will encourage farmers and agricultural industries to consider performing more distribution uniformity evaluations, ultimately improving irrigation water use efficiency and supporting sustainable water management in agriculture. 展开更多
关键词 Center Pivot IRRIGATION UNIFORMITY Sprinkler System evaluation water Saving UAV
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Performance evaluation of CLM5.0 in simulating liquid soil water in high mountainous area,Northwest China
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作者 ZHANG Lan-hui NING Feng-wei +2 位作者 BAI Xu-liang ZENG Xuan HE Chan-sheng 《Journal of Mountain Science》 SCIE CSCD 2023年第7期1865-1883,共19页
The model performance in simulating soil water content(SWC) is crucial for successfully modeling earth’s system,especially in high mountainous areas.In this study,the performance of Community Land Model 5.0(CLM5.0) i... The model performance in simulating soil water content(SWC) is crucial for successfully modeling earth’s system,especially in high mountainous areas.In this study,the performance of Community Land Model 5.0(CLM5.0) in simulating liquid SWC was evaluated against observations from nine in-situ sites in the upper reach of the Heihe River Watershed(HRW),Northwest China.The CLM5.0 shows reliable performance in the study area with correlation coefficients(R) ranging between 0.79–0.93,root mean standard errors(RMSE)ranging between 0.044–0.097 m^(3)/m^(3),and the mean bias(BIAS) ranging between-0.084–0.061 m^(3)/m^(3).The slightly worse performance of CLM5.0 than CLM4.5 on alpine meadow and grassland is mainly caused by the revised canopy interception parameterization.The CLM5.0 overestimates interception and underestimates evapotranspiration(ET) on both alpine meadow and grassland during the growth period.The systematical overestimations at all the grassland sites indicate that the underestimation of ET is much larger than the overestimation of interception on grassland during growth period,while the errors of simulated interception and ET are partially canceled out on alpine meadow.Moreover,the underestimation of ET is more responsible for the overestimation of SWC than the overestimation of interception in the high mountainous area.It is necessary to estimate reasonable empirical parameter α(proportion of leaf water collection area) in interception parameterization scheme and further improve the dry surface layerbased soil evaporation resistance parameterization introduced in CLM5.0 in future researches.The performance of CLM5.0 is better under completely frozen stage than thawing stage and freezing stage,because of low variations of liquid SWC caused by extremely low hydraulic conductivity of soils.The underestimation of liquid SWC under frozen state is caused by underestimation of soil temperature,which leads to more ice mass and less liquid water in total water content. 展开更多
关键词 Performance evaluation Soil water content CLM5.0 EVAPOTRANSPIRATION High mountainous area
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High-quality Development Evaluation System of Water Parks
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作者 Yongshen TANG Hailong ZHANG Lei ZHANG 《Asian Agricultural Research》 2023年第1期16-22,共7页
Based on the connotation of high-quality development of water parks,this study established an evaluation system from distinctive water conservancy characteristics,excellent ecological environment,strong cultural atmos... Based on the connotation of high-quality development of water parks,this study established an evaluation system from distinctive water conservancy characteristics,excellent ecological environment,strong cultural atmosphere,strong development momentum,safe and efficient management,and significant comprehensive benefits,including 23 main contents and 52 evaluation indicators.Delphi method was used to score,and the evaluation results were divided into 3 levels,thus forming the evaluation system of high-quality development of water parks.This evaluation system has been preliminarily applied to the collection and selection of typical cases of the first national high-quality development of water parks.A total of 30 typical cases of high-quality development of water parks in China were collected and selected,and the first batch of 10 benchmark scenic spots were announced for key recommendation,and considerable application results have been achieved. 展开更多
关键词 water parks High-quality development Main characteristics evaluation system
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Evaluation of Water Resources Carrying Capacity in Gansu Section of Yellow River Basin Based on Fuzzy Comprehensive Evaluation Model
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作者 Shuanbao LIN 《Meteorological and Environmental Research》 CAS 2023年第4期42-45,49,共5页
As a basic natural resource and strategic economic resource,the development and utilization of water resources is an important issue related to the national economy and people's livelihood.How to scientifically ev... As a basic natural resource and strategic economic resource,the development and utilization of water resources is an important issue related to the national economy and people's livelihood.How to scientifically evaluate the water resources carrying capacity is the premise to improve the regional water resources carrying capacity and ensure the regional water security.The Gansu section of the Yellow River basin is an important water conservation and recharge area.Whether the water resources in this area can ensure the normal operation of the ecosystem and whether it can carry the sustainable development of social economy is the key to realize the high-quality development of the Yellow River basin.In this study,from the three dimensions of water consumption per capita,water consumption of 10000 yuan GDP and ecological water use rate,by constructing the evaluation index system and index grading standard of water resources carrying capacity,the fuzzy comprehensive evaluation model was used to evaluate the water resources carrying capacity of Gansu section of the Yellow River Basin,in order to provide theoretical decision-making basis for the comprehensive development,utilization and planning management of water resources in Gansu section of the Yellow River basin and even the whole basin,and help the high-quality development of the Yellow River basin. 展开更多
关键词 Fuzzy comprehensive evaluation model water resources carrying capacity evaluation Yellow River basin Gansu section
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Investigation on Phytoplankton and Water Quality Evaluation in Landscape Water of Campus in Nanjing Xianlin University Town 被引量:4
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作者 王琳 李敬伟 +5 位作者 夏娴 赵璐 孙晨霞 田园园 汪育文 许小军 《Journal of Landscape Research》 2010年第11期80-83,共4页
The major phytoplankton was investigated and analyzed in landscape water of six campuses in Nanjing Xianlin University Town,and water quality was evaluated by single factor assessment method and comprehensive weighted... The major phytoplankton was investigated and analyzed in landscape water of six campuses in Nanjing Xianlin University Town,and water quality was evaluated by single factor assessment method and comprehensive weighted evaluation method.The result showed that the major phytoplankton groups were Cyanophyta,Chlorophyta and Bacillariophyta.Besides,each evaluation indicator showed that waterbodies in four campuses were eutrophicated and result of single factor evaluation showed water quality all belonged to poor category V.The result of comprehensive weighted assessment showed that waters in Nanjing Normal University and Nanjing University of Posts and Telecommunications were seriously polluted,cyanobacterial bloom appearing.Waters in Nanjing University of Chinese Medicine and Nanjing Forest Police College hadn't been eutrophicated. 展开更多
关键词 Campus’s LANDSCAPE water PHYTOPLANKTON water QUALITY evaluation
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Application of Fuzzy Comprehensive Evaluation Method Based on Entropy Weight to Evaluate Pond Water Quality 被引量:1
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作者 吴会民 张韦 +4 位作者 梁传辉 樊振中 谢刚 高勇 缴建华 《Agricultural Science & Technology》 CAS 2012年第3期664-668,共5页
[Objective] This study was to provide references for the evaluation of water quality in aquaculture ponds by evaluating the pond water quality using fuzzy comprehensive evaluation method based on entropy weight. [Meth... [Objective] This study was to provide references for the evaluation of water quality in aquaculture ponds by evaluating the pond water quality using fuzzy comprehensive evaluation method based on entropy weight. [Method] The fuzzy compre- hensive evaluation method based on entropy weight was used to evaluate the water quality in the ponds with Ukraine scale carp (Cyprinus carpio) as the main cultivated fish. The average size of the fish was 71.4 g/ind, and totally three groups of pond were set with the population density of 6 000, 9 000, 12 000 ind/hm2. [Result] According to the GB3838-2002 Environmental Quality Standards for Surface Water of China, the water quality of 6 000 ind/hm2 group was Grade I, and the water quality of 9 000 and 12 000 ind/hm2 were Grade V. [Conclusion] With the increasing of feeding density, the pond water quality would worsen, however, there is no difference on water quality between 9 000 and 12 000 ind/hm2 groups. 展开更多
关键词 water quality Aquaculture pond Fuzzy comprehensive evaluation method Entropy weight
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Comprehensive evaluation of water quality parameters in Tianjin Dagu Dainage Canal 被引量:1
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作者 董玉波 戴媛媛 +1 位作者 马超 孙学亮 《Marine Science Bulletin》 CAS 2014年第2期90-96,共7页
In this paper, some indices of sulfide, organic carbon, oil and heavy metals (copper, lead, zinc, cadmium, mercury, arsenic and chromium) in the sediments from Dagu Dainage Canal at the Bohai Bay during four seasons... In this paper, some indices of sulfide, organic carbon, oil and heavy metals (copper, lead, zinc, cadmium, mercury, arsenic and chromium) in the sediments from Dagu Dainage Canal at the Bohai Bay during four seasons in 2012 - 2013 are selected, and Water Quality Pollution Index (API) is applied to evaluate water quality indices, aiming for the systematic evaluation of the water quality of Dagu Dainage Canal. The results showed that four stations of D3, D6, D7and D9 for S2 had the type Ⅱand Ⅲ of water; others had the type Ⅰ ; the total level of TOC, TPH, Cu, Pb, Zn, Cd, Hg, As and Cr were type Ⅰ, Ⅳ, Ⅱ, Ⅴ, Ⅱ, Ⅴ, Ⅲ, Vand Ⅴ. Water Quality Pollution Index (API) was 3.28, which illustrated Dagu Dainage Canal was in the state of contamination and the degree of pollution exceeded the standard functional areas. 展开更多
关键词 Dagu Dainage Canal water quality indices spatial and temporadistribution comprehensive evaluation
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Evaluation Model of Carrying Capacity of Water Resources Based on Standardized Indices of Radial Basis Function
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作者 臧蕾 李祚泳 刘伟 《Agricultural Science & Technology》 CAS 2012年第6期1365-1367,共3页
[Objective] The aim was to study on RBF model about evaluation on carrying capacity of water resources based on standardized indices. [Method] The indices were transformed and the averages of standard values in differ... [Objective] The aim was to study on RBF model about evaluation on carrying capacity of water resources based on standardized indices. [Method] The indices were transformed and the averages of standard values in different levels were taken as the standardized values of components of central vectors for basic functions of RBF hidden nodes. Hence, the basic functions are suitable for most indices, simplifying expression and calculation of basic functions. [Result] RBF models concluded through Monkey-king Genetic Algorithm with weights optimization are used in evaluation on water carrying capacity in three districts in Changwu County in Shaanxi Province, which were in consistent with that through fuzzy evaluation. [Conclusion] RBF, simple and practical, is universal and popular. 展开更多
关键词 Indices standardization RBF water resource Carrying capacity evaluation model
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Entropy method for determination of weight of evaluating indicators in fuzzy synthetic evaluation for water quality assessment 被引量:214
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作者 ZOU Zhi-hong YUN Yi SUN Jing-nan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期1020-1023,共4页
Considering the difficulty of fuzzy synthetic evaluation method in calculation of the multiple factors and ignorance of the relationship among evaluating objects, a new weight evaluation process using entropy method w... Considering the difficulty of fuzzy synthetic evaluation method in calculation of the multiple factors and ignorance of the relationship among evaluating objects, a new weight evaluation process using entropy method was introduced. This improved method for determination of weight of the evaluating indicators was applied in water quality assessment of the Three Gorges reservoir area. The results showed that this method was favorable for fuzzy synthetic evaluation when there were more than one evaluating objects. One calculation was enough for calculating every monitoring point. Compared with the original evaluation method, the method predigested the fuzzy synthetic evaluation process greatly and the evaluation results are more reasonable. 展开更多
关键词 water quality evaluation FUZZY weight of evaluating indicator entropy method
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Comprehensive Evaluation on the Irrigation Water Quality in Turpan City Based on Matter Element Analysis Method 被引量:1
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作者 阿不都沙拉木.加拉力丁 王欣 师芸宏 《Agricultural Science & Technology》 CAS 2016年第1期239-244,共6页
Matter-element analysis method was used to construct the comprehensive matter-element model for the evaluation of the quality of various kinds of irrigation water in Turpan City to evaluate the quality of irrigation w... Matter-element analysis method was used to construct the comprehensive matter-element model for the evaluation of the quality of various kinds of irrigation water in Turpan City to evaluate the quality of irrigation water(such as river water,spring water, Karez well water, pumped well water) in Turpan City, Xinjiang. The results showed that the quality of the irrigation water was the best in October,which was in Grade I or Grade 2; in May, the quality of some of the irrigation water became poorer to Grade II, which was easy to soil salinization; in March, the detected qualities of the water samples water from the Meiyaogou basin were all in Grade IV, which was not suitable for farmland irrigation. The comparison on the evaluation results of matter-element analysis and fuzzy evaluation method showed that the results of the 2 methods were almost consistent with each other, and showed good uniformity. 展开更多
关键词 Matter element analysis Irrigation water water quality evaluation Turpan City
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Evaluation, prediction, and protection of water quality in Danjiangkou Reservoir, China 被引量:14
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作者 Xiao-kang Xin Ke-feng Li +1 位作者 Brian Finlayson Wei Yin 《Water Science and Engineering》 EI CAS CSCD 2015年第1期30-39,共10页
The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SN... The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SNWDP), which commenced transferring water in 2014. Integrated research on the evaluation, prediction, and protection of water quality in the Danjiangkou Reservoir was carried out in this study in order to improve environmental management. Based on 120 water samples, wherein 17 water quality indices were measured at 20 monitoring sites, a single factor evaluation method was used to evaluate the current status of water quality. The results show that the main indices influencing the water quality in the Danjiangkou Reservoir are total phosphorus (TP), permanganate index (CODM,), dissolved oxygen (DO), and five-day biochemical oxygen demand (BODs), and the concentrations of TP, BODs, ammonia nitrogen (NH3--N), CODM,, DO, and anionic surfactant (Surfa) do not reach the specified standard levels in the tributaries. Seasonal Mann--Kendall tests indicated that the CODMn concentration shows a highly significant increasing trend, and the TP concentration shows a significant increasing trend in the Danjiangkou Reservoir. The distribution of the main water quality indices in the Danjiangkou Reservoir was predicted using a two-dimensional water quality numerical model, and showed that the sphere of influence from the tributaries can spread across half of the Han Reservoir if the pollutants are not controlled. Cluster analysis (CA) results suggest that the Shending River is heavily polluted, that the Jianghe, Sihe, and Jianhe rivers are moderately polluted, and that they should be the focus of environmental remediation. 展开更多
关键词 water quality Single factor evaluation method Mann--Kendall test Numerical modeling Cluster analysis Dangjiangkou Reservoir
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Fuzzy Comprehensive Evaluation Model for Water Resources Carrying Capacity in Tarim River Basin,Xinjiang,China 被引量:56
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作者 MENG Lihong CHEN Yaning +1 位作者 LI Weihong ZHAO Ruifeng 《Chinese Geographical Science》 SCIE CSCD 2009年第1期89-95,共7页
This paper explores the method of comprehensive evaluation of water resources carrying capacity and sets up an evaluation model applying the fuzzy comprehensive evaluation method. Based on the data of nature,society,e... This paper explores the method of comprehensive evaluation of water resources carrying capacity and sets up an evaluation model applying the fuzzy comprehensive evaluation method. Based on the data of nature,society,economics and water resources of the Tarim River Basin in 2002,we evaluated the water resources carrying capacity of the basin by means of the model. The results show that the comprehensive grades are 0.438 and 0.454 for Aksu and Kashi prefectures respectively,where the current water resources exploitation and utilization has reached a relative high degree and there is only a very limited water carrying capacity,0.620 for Kizilsu Kirgiz Autonomous Prefecture,where water resources carrying capacity is much higher,and in between for Hotan Prefecture and Bayingolin Mongo-lian Autonomous Prefecture. As a whole,the comprehensive grade of the Tarim River Basin is 0.508 and the current water resources exploitation and utilization has reached a relative high degree. Thus,we suggest that the integrated management of the water resources in the basin should be strengthened in order to utilize water resources scientifically and sustainably. 展开更多
关键词 water resources capacity fuzzy comprehensive evaluation membership degree Tarim River Basin XINJIANG
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Evaluation of regional water resources carrying capacity based on binary index method and reduction index method 被引量:13
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作者 Hong-yuan Fang Sheng-wei Gan Chen-ying Xue 《Water Science and Engineering》 EI CAS CSCD 2019年第4期263-273,共11页
Based on the regional water resources carrying capacity(WRCC)evaluation principles and evaluation index system in the National Technical Outline of Water Resources Carrying Capacity Monitoring and Early Warning(hereaf... Based on the regional water resources carrying capacity(WRCC)evaluation principles and evaluation index system in the National Technical Outline of Water Resources Carrying Capacity Monitoring and Early Warning(hereafter referred to as the Technical Outline),this paper elaborates on the collection and sorting of the basic data of water resources conditions,water resources development and utilization status,social and economic development in basins,analysis and examination of integrity,consistency,normativeness,and rationality of the basic data,and the necessity of WRCC evaluation.This paper also describes the technique of evaluating the WRCC in prefecture-level cities and city-level administrative divisions in the District of the Taihu Lake Basin,which is composed of the Taihu Lake Basin and the Southeastern River Basin.The evaluation process combines the binary index evaluation method and reduction index evaluation method.The former,recommended by the Technical Outline,uses the total water use and the amount of exploited groundwater as evaluation indices,showing stronger operability,while the latter is developed by simplifying and optimizing the comprehensive index system with greater systematicness and completeness.The mutual validation and adjustment of the results of the above-mentioned two evaluation methods indicate that the WRCC of the District of the Taihu Lake Basin is overloaded in general because some prefecture-level cities and city-level administrative divisions in the Taihu Lake Basin and the Southeastern River Basin are in a severely overloaded state.In order to explain this conclusion,this paper analyzes the causes of WRCC overloading from the aspects of basin water environment,water resources development and utilization,water resources regulation and control ability,water resources utilization efficiency,and water resources management. 展开更多
关键词 water resources carrying capacity(WRCC) evaluation Binary index method Reduction index method Prefecture-level cities and city-level administrative divisions
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Catastrophe theory-based risk evaluation model for water and mud inrush and its application in karst tunnels 被引量:18
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作者 ZHU Jian-qun LI Tian-zheng 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第5期1587-1598,共12页
This paper presents a risk evaluation model of water and mud inrush for tunnel excavation in karst areas.The factors affecting the probabilities of water and mud inrush in karst tunnels are investigated to define the ... This paper presents a risk evaluation model of water and mud inrush for tunnel excavation in karst areas.The factors affecting the probabilities of water and mud inrush in karst tunnels are investigated to define the dangerousness of this geological disaster.The losses that are caused by water and mud inrush are taken into consideration to account for its harmfulness.Then a risk evaluation model based on the dangerousness-harmfulness evaluation indicator system is constructed,which is more convincing in comparison with the traditional methods.The catastrophe theory is used to evaluate the risk level of water and mud inrush and it has great advantage in handling problems involving discontinuous catastrophe processes.To validate the proposed approach,the Qiyueshan tunnel of Yichang-Wanzhou Railway is taken as an example in which four target segments are evaluated using the risk evaluation model.Finally,the evaluation results are compared with the excavation data,which shows that the risk levels predicted by the proposed approach are in good agreements with that observed in engineering.In conclusion,the catastrophe theory-based risk evaluation model is an efficient and effective approach for water and mud inrush in karst tunnels. 展开更多
关键词 risk evaluation model water and mud inrush catastrophe theory karst area TUNNELING
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FANN-Based Surface Water Quality Evaluation Model and Its Application in the Shaoguan Area 被引量:15
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作者 YANG Meini LI Dingfang YANG Jinbo XlONG Wei 《Geo-Spatial Information Science》 2007年第4期303-310,共8页
A fuzzy neural network model is proposed to evaluate water quality. The model contains two parts: first, fuzzy mathematics theory is used to standardize the samples; second, the RBF neural network and the BP neural n... A fuzzy neural network model is proposed to evaluate water quality. The model contains two parts: first, fuzzy mathematics theory is used to standardize the samples; second, the RBF neural network and the BP neural network are used to train the standardized samples. The proposed model was applied to assess the water quality of 16 sections in 9 rivers in the Shaoguan area in 2005. The evaluation result was compared with that of the RBF neural network method and the reported results in the Shaoguan area in 2005. It indicated that the performance of the proposed fuzzy neural network model is practically feasible in the application of water quality assessment and its operation is simple. 展开更多
关键词 fuzzy neural network RBF neural networks BP neural networks water quality evaluation
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Water quantity-quality combined evaluation method for rivers' water requirements of the instream environment in dualistic water cycle: A case study of Liaohe River Basin 被引量:2
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作者 WANG Xiqin ZHANG Yuan LIU Changming 《Journal of Geographical Sciences》 SCIE CSCD 2007年第3期304-316,共13页
In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed, and compared with the meaning of unitary water cycle. Based on the analysis of the relatio... In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed, and compared with the meaning of unitary water cycle. Based on the analysis of the relationship between environmental flows of river requirements, the efficiency of water resource usage, the consumption coefficient, and the concentration of waste water elimination, the water quantity and water quality calculation method of the environmental flows of river requirements in dualistic water cycle is developed, and the criteria for environmental flows of river requirements are established, and therefore the water quantity-quality combined evaluation of natural river flows requirements are realized Taking the Liaohe River as a model, the environmental flows of river requirements for Xiliao River, Dongliao River, mainstream Liaohe River, Huntai River and northeast rivers along the coasts of the Yellow and Bohai seas in unitary water cycle are calculated, each taking up 39.3%, 63.0%, 43.9%, 43.3% and 43.5% of runoff respectively. Evaluated according to Tennant recommended flow, the results show that: except Xiliao River is "median", the rest are all upon "good", the Dongliao River is even "very good". The corresponding results in dualistic water cycle are that, the proportion of natural flows for each river is 57.5%, 74.1%, 60.8%, 60.3% and 60.4%; while the combined evaluation results show that: considering "quantity", except Xiliao River, the rest rivers can all achieve the "quantity" criteria of the en- vironmental flows of river requirements, but if considering the aspect of "quality", only Dongliao River can reach the "quality" standard. By water quantity-quality combined evaluation method, only Dongliao River can achieve the criteria. So the water quality is the main factor that determines whether the environmental flows can meet the river ecosystem demands. 展开更多
关键词 dualistic water cycle RIVERS environmental flows of river requirements water quantity water quality evaluation Liaohe River
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Fuzzy Synthetic Evaluation of Water Quality of Naoli River Using Parameter Correlation Analysis 被引量:14
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作者 WANG Jianhua LU Xianguo +1 位作者 TIAN Jinghan JIANG Ming 《Chinese Geographical Science》 SCIE CSCD 2008年第4期361-368,共8页
In order to improve the effectiveness of Fuzzy Synthetic Evaluation (FSE) models, a Parameter Correlation Analysis (PCA) was introduced into the FSE and a case study was carried out in the Naoli River in the Sanjiang ... In order to improve the effectiveness of Fuzzy Synthetic Evaluation (FSE) models, a Parameter Correlation Analysis (PCA) was introduced into the FSE and a case study was carried out in the Naoli River in the Sanjiang Plain, Northeast China. The basic principle of the PCA is that the pairs of parameters which are highly correlated and linear with each other would contribute the same information to an assessment and one of them should be eliminated. The method of the PCA is that a correlation relationship among candidate parameters is examined before the FSE. If there is an apparent nonlinear or curvilinear relationship between two parameters, then both will be retained; if the correlation is significant (p<0.01), and the scatter plot suggests a linear relationship, then one of them will be deleted. However, which one will be deleted? For solving this problem, a sensitivity test was conducted and the higher sensitivity parameters remained. The results indicate that the original data should be preprocessed through the PCA for redundancy and variability. The study shows that introducing the PCA into the FSE can simplify the FSE calculation process greatly, while the results have not been changed much. 展开更多
关键词 Parameter Correlation Analysis (PCA) Fuzzy Synthetic evaluation (FSE) surface water quality Naoli River Sanjiang Plain
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Evaluation index system for positive operation of water conservancy projects 被引量:3
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作者 Qing-yuan ZHU Guo-hua FANG 《Water Science and Engineering》 EI CAS 2009年第4期110-117,共8页
The conditions for the positive operation of water conservancy projects are described in this paper. A scientific and effective evaluation index system was established based on frequency analysis, theoretical analysis... The conditions for the positive operation of water conservancy projects are described in this paper. A scientific and effective evaluation index system was established based on frequency analysis, theoretical analysis, and expert consultation. This evaluation index system can be divided into six first-level indices: the degree to which facilities are intact and functionality standards are reached, the status of operation and management funds, the rationality and degree of advancement of the management team structure, the adaptability and rationality of the water conservancy project management system, the degree of automatization and informationization of the management techniques, and the conduciveness of the exterior environment. The weights for evaluation indices were obtained through the analytic hierarchy process method with consideration of the difference between public welfare and profit-oriented water conservancy projects. This study provides a scientific method for evaluating the positive operation of water conservancy projects. 展开更多
关键词 water conservancy project positive operation evaluation index system analytic hierarchy process WEIGHT
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Relative Efficiency Evaluation on Water Resource Utilization 被引量:3
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作者 MA Ying 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第3期60-64,共5页
Water resource allocation was defined as an input-output question in this paper, and a preliminary input-output index system was set up. Then GEM (group eigenvalue method)-MAUE (multi-attribute utility theory) mod... Water resource allocation was defined as an input-output question in this paper, and a preliminary input-output index system was set up. Then GEM (group eigenvalue method)-MAUE (multi-attribute utility theory) model was applied to evaluate relative efficiency of water resource allocation plans. This model determined weights of indicators by GEM, and assessed the allocation schemes by MAUE. Compared with DEA (Data Envelopment Analysis) or ANN (Artificial Neural Networks), the mode was more applicable in some cases where decision-makers had preference for certain indicators 展开更多
关键词 water resource allocation group eigenvalue method multi-attribute utility theory evaluation
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Water Quality Evaluation in Tidal River Reaches of Liaohe River Estuary, China Using a Revised QUAL2K Model 被引量:7
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作者 YE Hanfeng GUO Shuhai +1 位作者 LI Fengmei LI Gang 《Chinese Geographical Science》 SCIE CSCD 2013年第3期301-311,共11页
Rivers in the Liaohe River Estuary area have been seriously polluted by discharges of wastewater containing petroleum pol- lutants and nutrients. In this paper, The Enhanced Stream Water Quality Model (QUAL2K) and i... Rivers in the Liaohe River Estuary area have been seriously polluted by discharges of wastewater containing petroleum pol- lutants and nutrients. In this paper, The Enhanced Stream Water Quality Model (QUAL2K) and its revised model as well as One-dimensional Tide Mean Model (1D model) were applied to predict and assess the water quality of the tidal fiver reach of the Liaohe River Estuary. Dissolved oxygen (DO), biochemical oxygen demand (BODs), ammonia nitrogen (NH3-N) and total phosphorus (TP) were chosen as water quality indices in the two model simulations. The modelled results show that the major reasons for degraded rivers remain petroleum and non-point source pollution. Tidal water also has a critical effect on the variation of water quality. The sensitivity analysis identifies that flow rate, point load and diffuse load are the most sensitive parameters for the four water quality indices in the revised QUAL2K simulation. Uncertainty analysis based on a Monte Carlo simulation gives the probability distribution of the four wa- ter quality indices at two locations (6.50 km and 44.84 km from the river mouth). The statistical outcomes indicate that the observed data fall within the 90% confidence intervals at all sites measured, and show that the revised QUAL2K gives better results in simulating the water quality of a tidal fiver. 展开更多
关键词 tidal river reach water quality evaluation revised QUAL2K model uncertainty analysis Liaohe River Estuary
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