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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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Construction of Tourist Satisfaction Degree Evaluation Model in Western Tourist Area by Performance Prism and Fuzzy Comprehensive Evaluation Method——with Lijiang in Yunnan Province as the Study Case
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作者 蒋蓉华 焦俊刚 刘曲华 《Journal of Landscape Research》 2010年第4期64-68,共5页
Starting from the utilization and protection of local knowledge, with the performance prism as the framework, the evaluation index system of tourist satisfaction degree was established. The weight was determined by us... Starting from the utilization and protection of local knowledge, with the performance prism as the framework, the evaluation index system of tourist satisfaction degree was established. The weight was determined by using AHP method. Finally, the investigating result was judged with fuzzy comprehensive evaluation method, the evaluation model of tourist satisfaction degree in western tourist area was built, and the case study was carried out. With Lijiang in Yunnan Province as example, according to AHP method, five dimensions weight of the performance prism, various KPI weight and consistency were obtained, fuzzy evaluation on tourist satisfaction degree was conducted. The results showed that the overall was satisfactory, but there were still some problems. Aiming at the utilization and protection of local knowledge, some corresponding countermeasures were put forward which will benefit for further development of tourism in Lijiang of Yunnan Province. 展开更多
关键词 Toursit SATISFACTION degree Performance PRISM Fuzzy comprehensive evaluation evaluation model
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Optimization of CO_2 separation technologies for Chinese refineries based on a fuzzy comprehensive evaluation model 被引量:2
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作者 Qian-Qian Song Qing-Zhe Jiang Zhao-Zheng Song 《Petroleum Science》 SCIE CAS CSCD 2015年第1期197-206,共10页
This study aims at determining the optimal CO2 separation technology for Chinese refineries, based on current available technologies, by the method of comprehensive evaluation. Firstly, according to the characteristic... This study aims at determining the optimal CO2 separation technology for Chinese refineries, based on current available technologies, by the method of comprehensive evaluation. Firstly, according to the characteristics of flue gas from Chinese refineries, three feasible CO2 separation technologies are selected. These are pressure swing adsorption (PSA), chemical absorption (CA), and membrane absorption (MA). Secondly, an economic assessment of these three techniques is carried out in accordance with cash flow analysis. The results show that these three techniques all have economic feasibility and the PSA technique is the best. Finally, to further optimize the three techniques, a two-level fuzzy comprehensive evaluation model is established, including economic, technological, and environmental factors. Considering all the factors, PSA is optimal for Chinese refineries, followed by CA and MA. Therefore, to reduce Chinese refineries carbon emission, it is suggested that CO2 should be captured from off-gases using PSA. 展开更多
关键词 Chinese refineries CO2 emission Separation technique Economic evaluation AHP-entropy method Fuzzy comprehensive evaluation model
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Comprehensive evaluation of 5G+smart distribution network based on combined weighting method-cloud model 被引量:5
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作者 Xiufan Ma Ying Wang +1 位作者 Zihao Liu Xiaoyu Feng 《Global Energy Interconnection》 EI CAS CSCD 2022年第6期675-691,共17页
With the large-scale application of 5G technology in smart distribution networks,the operation effects of distribution networks are not clear.Herein,we propose a comprehensive evaluation model of a 5G+smart distributi... With the large-scale application of 5G technology in smart distribution networks,the operation effects of distribution networks are not clear.Herein,we propose a comprehensive evaluation model of a 5G+smart distribution network based on the combination weighting and cloud model of the improved Fuzzy Analytic Hierarchy-Entropy Weight Method(FAHP-EWM).First,we establish comprehensive evaluation indexes of a 5G+smart distribution network from five dimensions:reliable operation,economic operation,efficient interaction,technological intelligence,and green emission reduction.Second,by introducing the principle of variance minimization,we propose a combined weighting method based on the improved FAHP-EWM to calculate the comprehensive weight,so as to reduce the defects of subjective arbitrariness and promote objectivity.Finally,a comprehensive evaluation model of 5G+smart distribution network based on cloud model is proposed by considering the uncertainty of distribution network node information and equipment status information.The example analysis indicates that the overall operation of the 5G+smart distribution network project is decent,and the weight value calculated by the combined weighting method is more reasonable and accurate than that calculated by the single weighting method,which verifies the effectiveness and rationality of the proposed evaluation method.Moreover,the proposed evaluation method has a certain guiding role for the large-scale application of 5G communication technology in smart distribution networks. 展开更多
关键词 5G+smart distribution network comprehensive evaluation Improved FAHP Variance minimization Normal cloud model
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FUZZY COMPREHENSIVE EVALUATION MODEL OF ECOLOGICAL DEMONSTRATION AREA 被引量:5
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作者 YU Ya-juan GUO Huai-cheng LIU Yong WANG Shu-tong WANG Jin-feng 《Chinese Geographical Science》 SCIE CSCD 2005年第4期303-308,共6页
Ecological demonstration area (EDA) is an authorized nomination, which should be assessed from several aspects, including ecological, social, environmental, economic ones and so on. It is difficult to advance an exact... Ecological demonstration area (EDA) is an authorized nomination, which should be assessed from several aspects, including ecological, social, environmental, economic ones and so on. It is difficult to advance an exact developing level index of EDA due to its indicator system’s complexity and disequilibrium. In this paper, a framework of indicators was set to evaluate, monitor and examine the comprehensive level of ecological demonstration area (EDA). Fuzzy logic method was used to develop the fuzzy comprehensive evaluation model (FCEM), which could quantitatively reveal the developing degree of EDA. Huiji District of Zhengzhou, Henan Province, one of the 9th group of national EDAs, was taken as a study case. The framework of FCEM for the integrated system included six subsystems, which were social, economic, ecological, rural, urban and accessorial description ones. The research would be valuable in the comprehensive quantitative evaluation of EDA and would work as a guide in the construction practices of Huiji ecological demonstration area. 展开更多
关键词 fuzzy comprehensive evaluation model (FCEM) ecological demonstration area (EDA) fuzzy logic system dynamics Huiji District of Zhengzhou
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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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Comprehensive Evaluation Model of Reservoir Operation Based on Improved Set Pair Analysis 被引量:4
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作者 任炳昱 孙宜超 +2 位作者 周正印 程正飞 胡兴富 《Transactions of Tianjin University》 EI CAS 2013年第1期25-28,共4页
A comprehensive evaluation model based on improved set pair analysis is established. Considering the complexity in decision-making process, the model combines the certainties and uncertainties in the schemes, i.e., id... A comprehensive evaluation model based on improved set pair analysis is established. Considering the complexity in decision-making process, the model combines the certainties and uncertainties in the schemes, i.e., identical degree, different degree and opposite degree. The relations among different schemes are studied, and the traditional way of solving uncertainty problem is improved. By using the gray correlation to determine the difference degree, the problem of less evaluation indexes and inapparent linear relationship is solved. The difference between the evaluation parameters is smaller in both the fuzzy comprehensive evaluation model and fuzzy matter-element method, and the dipartite degree of the evaluation result is unobvious. However, the difference between each integrated connection degree is distinct in the improved set pair analysis. Results show that the proposed method is feasible and it obtains better effects than the fuzzy comprehensive evaluation method and fuzzy matter-element method. 展开更多
关键词 set pair analysis comprehensive evaluation model gray correlation reservoir operation
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Multiple-Constraint-Aware RWA Algorithms Based on a Comprehensive Evaluation Model:Use in Wavelength-Switched Optical Networks
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作者 Hui Yang YongliZhao +3 位作者 Shanguo Huang Dajiang Wang Xuping Cao Xuefeng Lin 《ZTE Communications》 2012年第3期55-61,共7页
Because of explosive growth in Internet traffic and high complexity of heterogeneous networks, improving the routing and wavelength assignment (RWA) algorithm in underlying optical networks has become very important... Because of explosive growth in Internet traffic and high complexity of heterogeneous networks, improving the routing and wavelength assignment (RWA) algorithm in underlying optical networks has become very important. Where there are multiple links between different the node pairs, a traditional wavelength-assignment algorithm may be invalid for a wavelength-switched optical networks (WSON) that has directional blocking constraints. Also, impairments in network nodes and subsequent degradation of optical signals may cause modulation failure in the optical network. In this paper, we propose an RWA algorithm based on a novel evaluation model for a WSQN that has multiple constraints. The algorithm includes comprehensive evaluation model (CEM) and directional blocking constraint RWA based on CEM (DB-RWA). Diverse constraints are abstracted into various constraint conditions in order to better assign routing and wavelength. We propose using the novel CEM to optimize routing according to an assessed value of constraints on transmission performance. This eliminates the effects of physical transmission impairments in a WSON. DB-RWA based on CEM abstracts directional blocking conditions in multiple links between network nodes into directional blocking constraints. It also satisfies rigorous network specifications and provides flexibility, scalability, and first-fit rate for the backbone, especially in multiple links between WSON nodes. 展开更多
关键词 RWA WSON multiple links between nodes pair directionalblocking constraint comprehensive evaluation model
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Index Design and Comprehensive Evaluation of Germplasm Resources of Fruits Based on Mathematical Model of AHP and FCE:Sterculia nobilis Smith as a Case
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作者 Li Wen-yan Wei You Zhou Jing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2021年第2期35-44,共10页
The mathematical model of analytic hierarchy process(AHP)-fuzzy comprehensive evaluation(FCE)was applied to comprehensively evaluate the germplasm resources of Sterculia nobilis Smith,and the scientific nature and rel... The mathematical model of analytic hierarchy process(AHP)-fuzzy comprehensive evaluation(FCE)was applied to comprehensively evaluate the germplasm resources of Sterculia nobilis Smith,and the scientific nature and reliability of the mathematical model was verified by calculating index weights and comprehensive evaluation scores.In this paper,11 indicators were selected to construct a comprehensive evaluation system from four dimensions of yields,resistances,contents of main inclusions in seeds and tree shapes.AHP method was applied to calculate the index weight of each dimension,after passing the consistency test,FCE method was applied to comprehensively evaluate germplasm resources of S.nobilis Smith.The index weights of the yields,resistances,contents of major inclusions in seeds and tree shapes were 0.5518,0.2554,0.1279 and 0.0649,respectively.The yield had the greatest influence on the comprehensive evaluation of germplasm resources of S.nobilis Smith,which was in line with the actual production demand of S.nobilis Smith as a food crop.However,resistances and contents of major inclusions in seeds had limited influence on it,while tree shapes had the least influence on it.After fuzzy comprehensive evaluation,the final evaluation score was 88.00,the corresponding evaluation score was between 4 and 5,and the evaluation results ranged from slight good to good,which indicated that the evaluation weights corresponding to the four dimensions were more scientific and reasonable.In this study,the mathematical model of AHP-FCE was used to establish and evaluate the comprehensive evaluation system of the germplasm resources of S.nobilis Smith.According to the values of index weights and the evaluation results,it showed that the mathematical model was scientific and reliable,and it could provide a new reference method for the comprehensive evaluation of germplasm resources of other fruits. 展开更多
关键词 Sterculia nobilis Smith comprehensive evaluation AHP-FCE mathematical model germplasm resource
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Evaluation of Productive Plant Landscapes in Cold Regions Based on a Multiple Cropping Model
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作者 Wu Zhi-heng Zhang Jia-xin +2 位作者 Zhu Xuan-bo Pan Sheng-kai Yan Yong-qing 《Journal of Northeast Agricultural University(English Edition)》 2023年第4期43-52,共10页
Four varieties of each rapeseed and buckwheat were planted in different sowing periods to explore a variety of planting patterns.A theoretical foundation was provided for the innovative application of cold region prod... Four varieties of each rapeseed and buckwheat were planted in different sowing periods to explore a variety of planting patterns.A theoretical foundation was provided for the innovative application of cold region productive plant landscapes.The analytic hierarchy process was employed to develop a model for the evaluation of multiple cropping systems.A comprehensive evaluation was conducted to study 10 indicators in plant type,flower color,flowering period,flower volume,branch coverage,plot average yield,number of grains per plant,yield per plant,thousand-grain quality and ecological adaptability in four different varieties of each rapeseed and buckwheat.The results indicated that flower color,ecological adaptability,plot average yield and flower volume were the most important indicators for the value of productive plant landscapes in cold regions.Concerning the sowing period,the optimal combination of varieties and planting times were March 31 for Qingza No.5(rapeseed)and July 18 for Xinong T1211(buckwheat). 展开更多
关键词 multiple cropping model RAPESEED BUCKWHEAT analytic hierarchy process comprehensive evaluation
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A Comprehensive Model for Evaluating Coalbed Methane Reservoirs in China 被引量:19
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作者 YAO Yanbin LIU Dameng TANG Dazhen HUANG Wenhui TANG Shuheng CHE Yao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第6期1253-1270,共18页
Coalbed methane reservoir (CBMR) evaluation is important for choosing the prospective target area for coalbed methane exploration and production. This study aims at identifying the characteristic parameters and meth... Coalbed methane reservoir (CBMR) evaluation is important for choosing the prospective target area for coalbed methane exploration and production. This study aims at identifying the characteristic parameters and methods to evaluate CBMR. Based on the geological surveys, laboratory measurements and field works, a four-level analytic hierarchy process (AHP) model for CBMR evaluation is proposed. In this model, different weights are prioritized and assigned on the basis of three main criteria (including reservoir physical property, storage capacity and geological characteristics), 15 sub-criteria, and 18 technical alternatives; the later of which are discussed in detail. The model was applied to evaluate the CBMR of the Permo-Carboniferous coals in the Qinshui Basin, North China. This GIS-based fuzzy AHP comprehensive model can be used for the evaluation of CBMR of medium-high rank (mean maximum vitrinite reflectance 〉0.5 %) coal districts in China. 展开更多
关键词 coalbed methane reservoir reservoir evaluation reservoir characterization comprehensive model Fuzzy Hierarchy Process Approach (FAHP)
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Neural Network Based Multi-level Fuzzy Evaluation Model for Mechanical Kinematic Scheme
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作者 BO Ruifeng,LI Ruiqin (Department of Mechanical Engineering,North University of China,Taiyuan 030051,China) 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S1期301-306,共6页
To implement a quantificational evaluation for mechanical kinematic scheme more effectively,a multi-level and multi-objective evaluation model is presented using neural network and fuzzy theory. Firstly,the structure ... To implement a quantificational evaluation for mechanical kinematic scheme more effectively,a multi-level and multi-objective evaluation model is presented using neural network and fuzzy theory. Firstly,the structure of evaluation model is constructed according to evaluation indicator system. Then evaluation samples are generated and provided to train this model. Thus it can reflect the relation between attributive value and evaluation result,as well as the weight of evaluation indicator. Once evaluation indicators of each candidate are fuzzily quantified and fed into the trained network model,the corresponding evaluation result is outputted and the best alternative can be selected. Under this model,expert knowledge can be effectively acquired and expressed,and the quantificational evaluation can be implemented for kinematic scheme with multi-level evaluation indicator system. Several key problems on this model are discussed and an illustration has demonstrated that this model is feasible and can be regarded as a new idea for solving kinematic scheme evaluation. 展开更多
关键词 NEURAL network mechanical KINEMATIC SCHEME multi-level evaluation model FUZZY
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Construction scheme comparison with comprehensive evaluation of independent perspectives
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作者 阎西康 王磊 CHEN Pei 《Journal of Chongqing University》 CAS 2013年第3期131-135,共5页
Considering both the characteristics of construction scheme evaluation and the lack of consideration of index proportionality after introducing comprehensive evaluation of independent perspectives into construction sc... Considering both the characteristics of construction scheme evaluation and the lack of consideration of index proportionality after introducing comprehensive evaluation of independent perspectives into construction scheme evaluation, a construction scheme evaluation model of independent perspectives was put forward through the study and optimization of comprehensive evaluation of independent perspectives. The feasibility and rationality of the optimized method were illustrated through a case study and the evaluation results were compared between the optimized method and non-optimized method. The optimized method has the practical value in construction scheme comparison. 展开更多
关键词 construction scheme evaluation model independent perspective comprehensive evaluation
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Comprehensive Evaluation on the Agricultural Sustainable Development with the Smallest Generalized Deviation
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作者 LAN Tian-yi Basis Department,Xijing University,Xi’an 710123,China 《Asian Agricultural Research》 2011年第4期15-17,共3页
Evaluation index system of agricultural sustainable development is constructed with the four components of social index,agricultural economic index,resources index,and environment index.According to the comprehensive ... Evaluation index system of agricultural sustainable development is constructed with the four components of social index,agricultural economic index,resources index,and environment index.According to the comprehensive evaluation model of agricultural sustainable development with the participation of single person,comprehensive evaluation model of agricultural sustainable development with the smallest generalized deviation and the participation of many people is established.Based on the case studies,agricultural sustainable development status of a certain region is evaluated.Result shows that the evaluation scores of the social index and agricultural economic index are high in this region,but the score of resources index is general and the evaluation result of environment index is not very good.The comprehensive evaluation value of overall sustainable development is 0.665 5;and the evaluation result is "good". 展开更多
关键词 model with the smallest GENERALIZED deviation Sust
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Evaluation model for freeway incident management system 被引量:2
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作者 何锭 倪富健 杨顺新 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期126-131,共6页
In order to evaluate the general situation and find special problems of the freeway incident management system, an evaluation model is proposed. First, the expert appraisal approach is used to select the primary evalu... In order to evaluate the general situation and find special problems of the freeway incident management system, an evaluation model is proposed. First, the expert appraisal approach is used to select the primary evaluation index. As a result, 81 indices and the hierarchical structures of the index such as the object layer, the sub-object layer, the criterion layer and the index layer are determined. Then, based on the fuzzy characteristics of each index layer, the analytical hierarchy process(AHP)and the fuzzy comprehensive evaluation are applied to generate the weight and the satisfaction of the index and the criterion layers. When analyzing the relationship between the sub-object layer and the object layer, it is easy to find that the number of sub-objects is too large and sub-objects are significantly redundant. The partial least square (PLS) is proposed to solve the problems. Finally, an application example, whose result has already been accepted and employed as the indication of a new project in improving incident management, is introduced and the result verifies the feasibility and efficiency of the model. 展开更多
关键词 freeway incident management system evaluation model analytical hierarchical process fuzzy comprehensive evaluations partial least square
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Background modeling methods in video analysis: A review and comparative evaluation 被引量:4
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作者 Yong Xu Jixiang Dong +1 位作者 Bob Zhang Daoyun Xu 《CAAI Transactions on Intelligence Technology》 2016年第1期43-60,共18页
Foreground detection methods can be applied to efficiently distinguish foreground objects including moving or static objects from back- ground which is very important in the application of video analysis, especially v... Foreground detection methods can be applied to efficiently distinguish foreground objects including moving or static objects from back- ground which is very important in the application of video analysis, especially video surveillance. An excellent background model can obtain a good foreground detection results. A lot of background modeling methods had been proposed, but few comprehensive evaluations of them are available. These methods suffer from various challenges such as illumination changes and dynamic background. This paper first analyzed advantages and disadvantages of various background modeling methods in video analysis applications and then compared their performance in terms of quality and the computational cost. The Change detection.Net (CDnet2014) dataset and another video dataset with different envi- ronmental conditions (indoor, outdoor, snow) were used to test each method. The experimental results sufficiently demonstrated the strengths and drawbacks of traditional and recently proposed state-of-the-art background modeling methods. This work is helpful for both researchers and engineering practitioners. Codes of background modeling methods evaluated in this paper are available atwww.yongxu.org/lunwen.html. 展开更多
关键词 Background modeling Video analysis comprehensive evaluation
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Expert Anti-Evaluation Model Based on Matter-Element Analysis in Fund Project Peer-Review System
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作者 Haifeng Li Yanzhong Dang 《Intelligent Information Management》 2010年第3期227-231,共5页
The article analyses several key issues which restrict the effectiveness of fund project peer review work. It analyses the evaluating theory and matter-element theory to access the expert anti-evaluation model, and al... The article analyses several key issues which restrict the effectiveness of fund project peer review work. It analyses the evaluating theory and matter-element theory to access the expert anti-evaluation model, and also studies the expert anti-evaluation index system to support the anti-evaluation method. The practical basis is the true score data of the experts which is collected from the actual anti-evaluation in Liaoning province science and technology fund project peer review system. With the practical experience of the actual project, we prove that the expert index system anti-evaluation model and expert anti-evaluation method can improve the fund project peer review work and play a positive role for the peer review work and also make the review work more scientific and more rational. 展开更多
关键词 Anti-evaluation model MATTER-ELEMENT Analysis Index SYSTEM comprehensive evaluation PEER Review
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Study on Sex Ratio of Lampreys Based on Simulated Ecosystem-Food Web Model
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作者 Ziyuan Zhao Xinqi Hao Jinyang Xia 《Journal of Applied Mathematics and Physics》 2024年第8期2959-2989,共31页
Lampreys, as an important participant in the ecosystem, play an irreplaceable role in the stability of nature. A variety of models were used to simulate ecosystems and food webs, and the dynamic evolution of multiple ... Lampreys, as an important participant in the ecosystem, play an irreplaceable role in the stability of nature. A variety of models were used to simulate ecosystems and food webs, and the dynamic evolution of multiple populations was solved. The temporal changes of the biomass and the health of the ecosystem affected by the population of Lampreys in other ecological niches were solved. For problem 1, Firstly, a simple natural ecosystem is simulated based on the threshold model and BP neural network model. The dynamic change of the sex ratio of lampreys population and the fluctuation of ecosystem health value were found to generate time series maps. Lampreys overprey on low-niche animals, which damages the overall stability of the ecosystem. For problem 2, We used the Lotka-Volterra model to construct ecological competition between lampreys and primary consumers and predators. Then, the Lotka-Volterra equations were solved, and a control group without gender shift function was set up, which reflected the advantages and disadvantages of the sex-regulated characteristics of lampreys in the natural environment. For problem 3, The ecosystem model established in question 1 was further deepened, and the food web was simulated by the Beverton-Holt model and the Logistic time-dependent differential equations model. The parameters of the food web model were input into the neurons of the ecosystem model, and the two models were integrated to form an overall biosphere model. The output layer of the ecosystem neural network was input into the food web Beverton-Holt and Logistic differential equations, and finally, the three-dimensional analytical solution was obtained by numerical simulation. Then Euler method is used to obtain the exact value of the solution surface. The Random forest model was used to predict the future development of lampreys and other ecological niches. For problem 4, By investigating relevant literature, we normalized the populations of lampreys and a variety of fish as well as other ecological niche animals, plants and microorganisms in the same water area, set different impact weights of lampreys, constructed weight evaluation matrix, and obtained positive and negative ideal solution vectors and negative correlation proximity by using TOPSIS comprehensive evaluation method. It is concluded that many kinds of fish are greatly affected by the sex regulation of lampreys. 展开更多
关键词 BP Neural Network model LAMPREY Beverton-Holt and Logistic Differential Equations Systems TOPSIS comprehensive evaluation Method
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Water Quality Evaluation of Duyun-Kaili Section in the Upper Reaches of the Qingshui River Basin
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作者 SHANG Hailong XU Ruifang XIAO Yuexing 《Journal of Landscape Research》 2018年第4期86-89,共4页
The fuzzy mathematic model was used to evaluate the water quality of six sections in the upper reaches of the Qingshui River Basin. The results showed that tiie water of grade I accounted for a high proportion, with m... The fuzzy mathematic model was used to evaluate the water quality of six sections in the upper reaches of the Qingshui River Basin. The results showed that tiie water of grade I accounted for a high proportion, with mild pollution and strong self-deaning ability; the pollutants (f.g. ammonium nitrogen, total phosphorus and fluoride) at each section mainly came from phosphate mines and phosphorus chemical companies; and the water quaEty among different sections was in the order Chayuan, Xingren Bridge, Xiasi, Locomotive Section, Yingpan, Panghai (from superiority to inferiority). This study has important reference values fof improving the water envifonment, saf^uarding the safely of drinkiiig water supply and scientifically preventing and conttolling water pollution, in the basin. 展开更多
关键词 Fuzzy comprehensive evaluation model Watef quality evaluation Duyun-Kaili section of Qingshui River
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The Impact on the Environment and Economy Due to the Introduction of Electric Cars: Based on the Fuzzy Synthetical Evaluation Method
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作者 Heli Gao 《Journal of Applied Mathematics and Physics》 2016年第12期2172-2185,共14页
In this paper, we establish a model to analyze the influence of widespread use of electric vehicle on environment, society and economist based on Fuzzy Comprehensive Evaluation method. We set the fuzzy objects are int... In this paper, we establish a model to analyze the influence of widespread use of electric vehicle on environment, society and economist based on Fuzzy Comprehensive Evaluation method. We set the fuzzy objects are internal combustion engine vehicles, pure electric vehicles and hybrid electric vehicles. Considering the difference of environment, society and economics, we use of three different kinds to define the fuzzy evaluation factor sets. According to the data and calculating results, we finally obtain fuzzy synthetical evaluation matrix. Through comparing and analysis, we draw such conclusion that the widespread using of electric vehicle is benefit for both environment and economics, while has disadvantageous influence for some aspects on society. In Section 3, we establish a model to estimate the influence of widespread use of electric vehicles on energy saving. According to the proportion of coal resources in the whole energies, we use Linear Regression Model to forecast the development situation in the following several years. Contrasting energy consumptions of electric vehicles and internal combustion engine vehicles, we calculate the whole energies saved by widespread use of electric vehicles. In Section 4, we establish a multi-objective programming model to plan the number and type of power station. Considering the thermal power, hydropower, nuclear power and solar power as four ways, combined with the funds of setting up power station, running funds and the cost of dealing with the pollutants, we find the objective function and four constraints, and finally we reach optimal solution using lingo software. 展开更多
关键词 Electric Vehicle Fuzzy comprehensive evaluation Linear Regression model Multi-Objective Programming model
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