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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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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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Catastrophe theory-based risk evaluation model for water and mud inrush and its application in karst tunnels 被引量:19
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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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Evaluation and optimization of secondary water supply system renovation 被引量:5
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作者 TIAN Yi-mei SI Yan-jie +1 位作者 LI Hong WU Mi-fang 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第9期1488-1494,共7页
Due to pollution in second water supply system (SWSS),nine renovation alternative plans were proposed and com-prehensive evaluations of different plan based on Analytical Hierarchy Process (AHP) were presented in this... Due to pollution in second water supply system (SWSS),nine renovation alternative plans were proposed and com-prehensive evaluations of different plan based on Analytical Hierarchy Process (AHP) were presented in this paper. Comparisons of advantages and disadvantages among the plans of SWSS renovations provided solid foundation for selecting the most appro-priate plan for engineering projects. In addition,a mathematical model of the optimal combination of renovation plans has been set up and software Lingo was used to solve the model. As a case study,the paper analyzed 15 buildings in Tianjin City. After simulation of the SWSS renovation system,an optimal scheme was obtained,the result of which indicates that 10 out of those 15 buildings need be renovated in priority. The renovation plans selected for each building are the ones ranked higher in the com-prehensive analysis. The analysis revealed that the optimal scheme,compared with two other randomly calculated ones,increased the percentage of service population by 19.6% and 13.6% respectively,which significantly improved social and economical benefits. 展开更多
关键词 Secondary water supply system (SWSS) Renovation plan Analytical Hierarchy Process (AHP) Hierarchical model OPTIMIZATION
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Quality Evaluation and Its Application to Surface Water Ecosystem Based on Maximum Flux Principle 被引量:3
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作者 刘年磊 毛国柱 赵林 《Transactions of Tianjin University》 EI CAS 2010年第5期336-341,共6页
Based on the maximum flux principle(MFP),a water quality evaluation model for surface water ecosystem is presented by using self-organization map(SOM) neural network simulation algorithm from the aspect of systematic ... Based on the maximum flux principle(MFP),a water quality evaluation model for surface water ecosystem is presented by using self-organization map(SOM) neural network simulation algorithm from the aspect of systematic structural evolution.This evaluation model is applied to the case of surface water ecosystem in Xindu District of Chengdu City in China.The values reflecting the water quality of five cross-sections of the system at different developing stages are obtained,with stable values of 1.438,2.952,1.86... 展开更多
关键词 evaluation model maximum flux principle surface water ecosystem self-organization map
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An evaluation of the simulations of the Arctic Intermediate Water in climate models and reanalyses 被引量:1
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作者 LI Xiang SU Jie ZHAO Jinping 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第12期1-14,共14页
The simulations of the Arctic Intermediate Water in four datasets of climate models and reanalyses, CCSM3, CCSM4, SODA and GLORYS, are analyzed and evaluated. The climatological core temperatures and depths in both CC... The simulations of the Arctic Intermediate Water in four datasets of climate models and reanalyses, CCSM3, CCSM4, SODA and GLORYS, are analyzed and evaluated. The climatological core temperatures and depths in both CCSM models exhibit deviations over 0.5°C and 200 m from the PHC. SODA reanalysis reproduces relatively reasonable spatial patterns of core temperature and depth, while GLORYS, another reanalysis, shows a remarkable cooling and deepening drift compared with the result at the beginning of the dataset especially in the Eurasian Basin (about 2°C). The heat contents at the depth of intermediate water in the CCSM models are overestimated with large positive errors nearly twice of that in the PHC. To the contrary, the GLORYS in 2009 show a negative error with a similar magnitude, which means the characteristic of the water mass is totally lost. The circulations in the two reanalyses at the depth of intermediate water are more energetic and realistic than those in the CCSMs, which is attributed to the horizontal eddy-permitting reso-lution. The velocity fields and the transports in the Fram Strait are also investigated. The necessity of finer horizontal resolution is concluded again. The northward volume transports are much larger in the two re-analyses, although they are still weak comparing with mooring observations. Finally, an investigation of the impact of assimilation is done with an evidence of the heat input from assimilation. It is thought to be a reason for the good performance in the SODA, while the GLORYS drifts dramatically without assimilation data in the Arctic Ocean. 展开更多
关键词 Arctic Intermediate water model evaluation Arctic modeling impact of data assimilation
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Evaluation of water resources conserved by forests in the Hani rice terraces system of Honghe County,Yunnan,China:an application of the fuzzy comprehensive evaluation model 被引量:10
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作者 LI Jing MIN Qingwen +3 位作者 LI Wenhua BAI Yanying YANG Lun Dhruba Bijaya G C 《Journal of Mountain Science》 SCIE CSCD 2016年第4期744-753,共10页
The Hani Rice Terraces System, based on gravity-flow irrigation, is one of the Globally Important Agricultural Heritage Systems(GIAHS) pilot sites selected by FAO in 2010. The water resource plays an important role in... The Hani Rice Terraces System, based on gravity-flow irrigation, is one of the Globally Important Agricultural Heritage Systems(GIAHS) pilot sites selected by FAO in 2010. The water resource plays an important role in the sustainable development of this system. The value of water conserved by the forest is influenced by natural, economic and social factors. In this paper, the water quality, per capita water resources, per capita GDP and population density are chosen as indices to construct an index system for a comprehensive evaluation of water resources value. The weights of these indices are 0.443, 0.31, 0.141 and 0.106 respectively, which are determined by the analytic hierarchy process(AHP) method. The water resources value has been assessed by the fuzzy comprehensive evaluation model. The results show that the water resources value in the Hani Rice Terraces System is 4.25 RMB/m^3. Evaluating the value of water resources in the Hani Rice Terraces System can provide a reference for ecological compensation, for raising public awareness of the importance of protecting the system, and ultimately achieving its sustainable development. 展开更多
关键词 Fuzzy comprehensive evaluation model water resources Hani Rice Terrace water value Globally Important Heritage systems(GIAHS)
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Construction and Application of Combined Evaluation Model of Regional Water Quality Plan 被引量:3
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作者 ZHANG Ming ZHOU Run-juan DU Ya-xi 《Meteorological and Environmental Research》 2012年第1期76-78,共3页
[Objective] The aim was to study the construction and application of combined evaluation model of regional water quality plan. [Meth- od] By dint of layer analysis, subjective and objective model of entropy evaluation... [Objective] The aim was to study the construction and application of combined evaluation model of regional water quality plan. [Meth- od] By dint of layer analysis, subjective and objective model of entropy evaluation, the water quality plan in Jinghe was evaluated. Combined evalu- ation model based on information entropy were constructed, and considering the single model evaluation result, the optimal water quality plan was selected. [ Result] The combination weight result suggested that COD amount was the most essential indicator in water quality plan and embodied the importance of water environment protection, which met basic objective of environment protection and social, economic effects. Combined evalu- ation indicated that in the sixteen plans, plan 16 was of highest comprehensive evaluation value, and can be considered as optimum water quality plan. [ Conclusion] Combined evaluation model can effectively list the advantages of each evaluation model and improve the dependability of water quality plan, and provided a new research idea for the optimal evaluation of water pollution control plan. 展开更多
关键词 water quality plan Combined evaluation Layer analysis method Entropy method WEIGHT China
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Dynamic evaluation of water resources carrying capacity of the Dianchi Lake Basin in 2005-2015,based on DSPERM framework model and simulated annealing-projection pursuit model 被引量:1
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作者 Jiayang Wang Xiaoqin Mu +3 位作者 Shouji Chen Wei Liu Zhuo Wang Zhanfeng Dong 《Regional Sustainability》 2021年第2期189-201,共13页
With the intensi fed impact of human activities,most lakes have been severely disturbed and the lake ecosystem has been seriously damaged,which exerted a great impact on the living envi-ronment of human beings in the ... With the intensi fed impact of human activities,most lakes have been severely disturbed and the lake ecosystem has been seriously damaged,which exerted a great impact on the living envi-ronment of human beings in the lake basins.The health of the lake ecosystem has gradually become one of the hot issues in recent years.In this study,the water resources carrying capacity(WRCC)was used to reveal the chain rel ationship between human activities and water environ-ment in the economic dewelopment of the Dianchi Lake Basin in Kunming City of China during 2005-2015.Specifically,we chose 25 ewaluation indicators related to the water environment and socialeconomic activities,classified them into six subsystems,Le,the driwing force subsystem(D),the water resources si tuation and consumption subsystem(S),the water resources pressure subsystem(P),the water environmental situation subsystem(E),the response subsystem(R),and the management subsystem(M),and built a comprehensive assessment system-DSPERM frame-work model.Si mulated annealing-projection pursuit model which reflects the structure or feature of high-dimensional data was adopted to calculate the WRCC of the Dianchi Lake Basin during 2005-2015 by weighting each evaluation indicator and each subsystem of the DSPERM frame work model.The resuls show that the WRCC of the Dlanchi Lake Basin was in level II(medium carying capacity)from 2005 to 2012.Since 2013,the WRCC has been at level II(strong carying capacity),and from 2005 to 2015,it showed a gradual upward trend.The evaluation indicators of each subsystem varied greatly and exhibited different development trends.The indicators of the water resources pressure subsystem had the greatest impact on the WRCC,followed by the in-dicators of the water environmental si tuation subsystem and the water resources situation and consumption subsystem.We recommend that the DSPERM framework model and the simulated anneal ing-projection pursuit model constructed in this work can be used to analyze the dynamic changes of the WRCC over the years.They have the advantages of practicability and feasibilty,and can provide the basis for the scienti fic decision-making and comprehensive management of regional water environment planning. 展开更多
关键词 water resources carrying capacity DSPERM framework model Annealing-projection pursuit model evaluation indicator Dianchi Lake Basin
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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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Development and application of a two-dimensional water quality model for the Daqinghe River Mouth of the Dianchi Lake 被引量:12
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作者 CHEN Qiuwen TAN Kui +1 位作者 ZHU Chuanbao LI Ruonan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第3期313-318,共6页
Water quality models are important tools to support the optimization of aquatic ecosystem rehabilitation programs and assess their efficiency. Basing on the flow conditions of the Daqinghe River Mouth of the Dianchi L... Water quality models are important tools to support the optimization of aquatic ecosystem rehabilitation programs and assess their efficiency. Basing on the flow conditions of the Daqinghe River Mouth of the Dianchi Lake, China, a two-dimensional water quality model was developed in the research. The hydrodynamics module was numerically solved by the alternating direction iteration (ADI) method. The parameters of the water quality module were obtained through the in situ experiments and the laboratory analyses that were conducted from 2006 to 2007. The model was calibrated and verified by the observation data in 2007. Among the four modelled key variables, i.e., water level, COD (in CODcr), NH4+-N and PO43-P the minimum value of the coefficient of determination (COD) was 0.69, indicating the model performed reasonably well. The developed model was then applied to simulate the water quality changes at a downstream cross-section assuming that the designed restoration programs were implemented. According to the simulated results, the restoration programs could cut down the loads of COD and PO43-P about 15%. Such a load reduction, unfortunately, would have very little effect on the NH4^+-N removal. Moreover, the water quality at the outlet cross-section would be still in class V (3838-02), indicating more measures should be taken to further reduce the loads. The study demonstrated the capability of water quality models to support aquatic ecosystem restorations. 展开更多
关键词 two-dimensional water quality model parameter estimation restoration program evaluation Dianchi Lake
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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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Comprehensive Evaluation of Water Quality of Rivers in Binzhou Based on RAGA-PPCE Model 被引量:1
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作者 Li Xin Guo Ning 《Meteorological and Environmental Research》 CAS 2018年第6期62-65,共4页
The water quality of main rivers in Binzhou City,Shandong Province was comprehensively evaluated based on RAGA-PPCE model. Six main factors such as ammonia nitrogen(NH-N),total phosphorus(TP),total nitrogen(TN),chemic... The water quality of main rivers in Binzhou City,Shandong Province was comprehensively evaluated based on RAGA-PPCE model. Six main factors such as ammonia nitrogen(NH-N),total phosphorus(TP),total nitrogen(TN),chemical oxygen demand(COD),dissolved oxygen(DO) and p H were used to establish the evaluation and classification standards of water quality. The results show that the evaluation results of water quality by RAGA-PPCE model and the fuzzy comprehensive evaluation method are basically the same. The evaluation results of RAGA-PPCE model are objective and reasonable and can be applied to the comprehensive evaluation of water quality. 展开更多
关键词 RAGA-PPCE model evaluation of water quality Projection pursuit Binzhou City
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An improved BP neural network based on evaluating and forecasting model of water quality in Second Songhua River of China 被引量:4
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作者 Bin ZOU Xiaoyu LIAO +1 位作者 Yongnian ZENG Lixia HUANG 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期167-167,共1页
关键词 河流 水质 人工神经网络 水文化学
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Complex Sequence Quality Evaluation Model for Concealed Water Supply Pipeline of Prefabricated Construction
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作者 HAN Shasha CHEN Qun +1 位作者 LI Jie DAI Yijing 《Journal of Donghua University(English Edition)》 EI CAS 2019年第2期179-186,共8页
The accurate assessment of the quality can materially affect the safety and life of the prefabricated construction.In this paper,we studied the overall module of concealed water supply pipeline,and a new complex seque... The accurate assessment of the quality can materially affect the safety and life of the prefabricated construction.In this paper,we studied the overall module of concealed water supply pipeline,and a new complex sequence quality evaluation model was established.By analyzing the small evaluation index elements of the model,the weight of the larger evaluation index could be deduced.The total quality evaluation score of the overall module could be obtained by calculating the weight value of the evaluation index,and then the quality standard of the overall module could be obtained. 展开更多
关键词 PREFABRICATED construction concealed water supplypipeline overall MODULE COMPLEX SEQUENCE QUALITY evaluation model QUALITY evaluation system
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Applying PP Model Based on RAGA in Water Environment Quality Evaluation
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作者 PANFeng FUQiang +1 位作者 LIANGChuan LIUDong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第2期171-175,共5页
Projection Pursuit (PP) model is a technique of falling high dimension. Real coding based on Accelerating Genetic Algorithm (RAGA) is a method of optimum. Through combining the PP model and RAGA, the paper applies the... Projection Pursuit (PP) model is a technique of falling high dimension. Real coding based on Accelerating Genetic Algorithm (RAGA) is a method of optimum. Through combining the PP model and RAGA, the paper applies the model in the water environment quality evaluation. The writer takes the water quality evaluated indexes of each sample as projection direction and turns high dimension data into low dimension projection value. Thus, the writer achieves on evaluating the grade of water samples and its optimum order. Based on this, the writer overcomes the jamming of weights calculated on fuzzy synthesize judge and gray system valuation. The paper can provide a new thought for water environment quality evaluation and other falling high dimension and optimum issue. 展开更多
关键词 RAGA PP model water environment quality evaluation
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Comprehensive Evaluation of Spatial Form Planning for Campuses of Newly-upgraded Undergraduate Universities
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作者 邓云叶 杨贤均 《Journal of Landscape Research》 2010年第5期30-34,共5页
According to the analysis on the present situation and development tendency of the campus spatial form planning of newly-upgraded undergraduate universities as well as its functions and characteristics,15 evaluation i... According to the analysis on the present situation and development tendency of the campus spatial form planning of newly-upgraded undergraduate universities as well as its functions and characteristics,15 evaluation indices were ascertained and the comprehensive evaluation model of the planning was established by AHP(Analytic Hierarchy Process).The results showed that AHP could effectively ascertain the evaluation indices system.Through calculating the weight of each index and judging the consistency of matrixes,key factors that can influence the campus spatial form planning were obtained,such as public green space,landscape node,visual contact axis,landscape axis,central plaza and teaching group space. 展开更多
关键词 CAMPUS Landscape planning AHP evaluation model
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Impacts of water resource planning on regional water consumption pattern: A case study in Dunhuang Oasis, China 被引量:3
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作者 ZHANG Xifeng JIN Xin +2 位作者 BAI Xiao JIANG Yanbin HE Chansheng 《Journal of Arid Land》 SCIE CSCD 2019年第5期713-728,共16页
Water resources are critical for the existence and development of oases in endorheic basins.Thus,to enable sustainable development,it is fundamentally important to understand how to allocate and use these resources in... Water resources are critical for the existence and development of oases in endorheic basins.Thus,to enable sustainable development,it is fundamentally important to understand how to allocate and use these resources in a reasonable way.We therefore simulated and analyzed changes in water consumption pattern within the Dunhuang Oasis of China under three scenarios using a system dynamic model that corresponds to different water consumption pattern.This was done to assess the impacts of regional water resource planning(comprehensive planning of the rational use of water resource and protection of ecosystem services in the Dunhuang Basin)on water consumption pattern within the Dunhuang Oasis.The first of these,Scenario 1,is a baseline in which the status quo is maintained,while Scenario 2 incorporates the comprehensive effects of agricultural water-saving irrigation measures with an inter-basin water diversion project,and Scenario 3 focuses on ecological rehabilitation.In the baseline Scenario 1,the total water consumption within the Dunhuang Oasis increased progressively while agricultural water consumption remained extremely high and threatened overall ecological security.In contrast,Scenario 2 would decrease agricultural water consumption by almost 5.30×10^7 m^3 following the implementation of water-saving practices.The additional water allocated from an inter-basin water diversion project would play an important role in alleviating ecological strain on the oasis.Finally,in Scenario 3,the total irrigated land must be decreased to 20.6×10^3 hm^2 by 2025 assuming that water supply for ecosystem restoration would be at least 50%of the total consumption.Although water resource planning plays a very important role in alleviating the ecological water crisis within the oasis,it is necessary to consider the suitable scale of oasis with regard to current water consumption pattern. 展开更多
关键词 water RESOURCES planning water CONSUMPTION pattern system dynamics model ECOLOGICAL REHABILITATION Dunhuang OASIS
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An attribute recognition model based on entropy weight for evaluating the quality of groundwater sources 被引量:21
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作者 CHEN Suo-zhong WANG Xiao-jing ZHAO Xiu-jun 《Journal of China University of Mining and Technology》 EI 2008年第1期72-75,共4页
In our study, entropy weight coefficients, based on Shannon entropy, were determined for an attribute recognition model to model the quality of groundwater sources. The model follows the theory previously proposed by ... In our study, entropy weight coefficients, based on Shannon entropy, were determined for an attribute recognition model to model the quality of groundwater sources. The model follows the theory previously proposed by Chen Q S. In the model, firstly, the author establishes the attribute space matrix and determines the weight based on Shannon entropy theory; secondly, calculates attribute measure; thirdly, evaluates that with confidence criterion and score criterion; finally, an application example is given. The results show that the water quality of the groundwater sources for the city comes up to the grade II or III standard. There is no pollution that obviously exceeds the standard and the water can meet people’s needs .The results from an evaluation of this model are in basic agreement with the observed situation and with a set pair analysis (SPA) model. 展开更多
关键词 water quality evaluation groundwater sources entropy weigh attribute recognition model
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Fog simulation using a mesoscale model in and around the Yodo River Basin,Japan 被引量:4
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作者 HIKARI Shimadera KUNDAN Lal Shrestha +2 位作者 AKIRA Kondo AKIKAZU Kaga YOSHIO Inoue 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第7期838-845,共8页
In this study,fog simulations were conducted using the Fifth-Generation NCAR/Penn State Mesoscale Model (MM5) in and around the Yodo River Basin,Japan.The purpose is to investigate the MM5 performance of fog simulatio... In this study,fog simulations were conducted using the Fifth-Generation NCAR/Penn State Mesoscale Model (MM5) in and around the Yodo River Basin,Japan.The purpose is to investigate the MM5 performance of fog simulation for long-term periods.The simulations were performed for January,February,March,and July,2005 with a coarse 3-kin and a nested fine 1-km grid domains. Results of the simulations were compared with data from ten meteorological observatories,fog sampling site in Mt.Rokko,and visibility measurem... 展开更多
关键词 fog simulation the Fifth-Generation NCAR/Penn State Mesoscale model (MM5) model evaluation occurrence of fog liquid water content
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