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An evaluation method of contribution rate based on fuzzy Bayesian networks for equipment system-of-systems architecture
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作者 XU Renjie LIU Xin +2 位作者 CUI Donghao XIE Jian GONG Lin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期574-587,共14页
The contribution rate of equipment system-of-systems architecture(ESoSA)is an important index to evaluate the equipment update,development,and architecture optimization.Since the traditional ESoSA contribution rate ev... The contribution rate of equipment system-of-systems architecture(ESoSA)is an important index to evaluate the equipment update,development,and architecture optimization.Since the traditional ESoSA contribution rate evaluation method does not make full use of the fuzzy information and uncertain information in the equipment system-of-systems(ESoS),and the Bayesian network is an effective tool to solve the uncertain information,a new ESoSA contribution rate evaluation method based on the fuzzy Bayesian network(FBN)is proposed.Firstly,based on the operation loop theory,an ESoSA is constructed considering three aspects:reconnaissance equipment,decision equipment,and strike equipment.Next,the fuzzy set theory is introduced to construct the FBN of ESoSA to deal with fuzzy information and uncertain information.Furthermore,the fuzzy importance index of the root node of the FBN is used to calculate the contribution rate of the ESoSA,and the ESoSA contribution rate evaluation model based on the root node fuzzy importance is established.Finally,the feasibility and rationality of this method are validated via an empirical case study of aviation ESoSA.Compared with traditional methods,the evaluation method based on FBN takes various failure states of equipment into consideration,is free of acquiring accurate probability of traditional equipment failure,and models the uncertainty of the relationship between equipment.The proposed method not only supplements and improves the ESoSA contribution rate assessment method,but also broadens the application scope of the Bayesian network. 展开更多
关键词 equipment system-of-systems architecture(ESoSA) contribution rate evaluation fuzzy Bayesian network(FBN) fuzzy set theory
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Selection of the best initial orbital elements of satellite based on fuzzy integration evaluation method 被引量:3
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作者 Yang Yong'an Zhang Hongwei +1 位作者 Feng Zuren Luo Yongjin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期566-570,共5页
The fuzzy integration evaluation method (FIEM) is studied in order to select the best orbital elements from the multi-group initial orbits determined by a satellite TT&C (Tracking, Telemetry and Control) center w... The fuzzy integration evaluation method (FIEM) is studied in order to select the best orbital elements from the multi-group initial orbits determined by a satellite TT&C (Tracking, Telemetry and Control) center with all kinds of data sources. By employing FIEM together with the experience of TT&C experts, the index system to evaluate the selection of the best initial orbits is established after the data sources and orbit determination theories are studied. Besides, the concrete steps in employing the method are presented. Moreover, by taking the objects to be evaluated as evaluation experts, the problem of how to generate evaluation matrices is solved. Through practical application, the method to select the best initial orbital elements has been proved to be flexible and effective The originality of the method is to find a new evaluation criterion (comparing the actually tracked orbits) replacing the traditional one (comparing the nominal orbits) for selecting the best orbital elements. 展开更多
关键词 system engineering fuzzy integration evaluation method SATELLITE initial orbit TT&C system.
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Construction of Urban-rural Integration Evaluation System in Nanchang City and Empirical Studies
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作者 SUN Kai LIU Jiahao 《Journal of Landscape Research》 2015年第5期25-27,共3页
Taking Nanchang City, Jiangxi Province for example, this paper took 17 sub-indexes from five fields, namely integration of space, population, society, economy and ecology to analyze the dynamic urban-rural integration... Taking Nanchang City, Jiangxi Province for example, this paper took 17 sub-indexes from five fields, namely integration of space, population, society, economy and ecology to analyze the dynamic urban-rural integration of the city in the past decade, compared it with fruits of Beijing, Shanghai and Suzhou, and concluded that the future urban-rural integration of Nanchang should be carried out from the perspectives of optimization of industrial structure, population agglomeration, issues concerning "agriculture, rural areas and peasants", and environmental protection. 展开更多
关键词 evaluation system Urban-rural integration Nanchang City
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Integration degree of tourism industry based on AHP-fuzzy comprehensive evaluation 被引量:3
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作者 YAN Wei 《Ecological Economy》 2014年第2期172-176,共5页
By reviewing the traditional measure methods of the integration degree of the tourism industry, we concluded that measure methods of the integration degree of the tourism industry can only be limited to the levels of ... By reviewing the traditional measure methods of the integration degree of the tourism industry, we concluded that measure methods of the integration degree of the tourism industry can only be limited to the levels of theoretical analysis due to the defect of the statistical data and the statistical structure. With the help of concept of fusion field and fusion entropy of the tourism industry, a physical model of integration of the tourism industry is established and index system based on AHP is proposed. Using AHP-fuzzy comprehensive evaluation method, the integration degree of Jiangsu and the country's tourism industry are studied. The influencing factors are analyzed and the corresponding countermeasures are proposed. 展开更多
关键词 integration DEGREE TOURISM INDUSTRY AHP FUZZY COMP
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Construction of Evaluation System for High-quality Development of Characteristic Towns from the Perspective of Production-Living-Ecology Integration
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作者 Hongxia DONG Hui WANG 《Asian Agricultural Research》 2020年第12期1-5,共5页
From the perspective of production-living-ecology integration,an evaluation system,involving production quality,living quality and ecological quality,was constructed in this article for high-quality development of cha... From the perspective of production-living-ecology integration,an evaluation system,involving production quality,living quality and ecological quality,was constructed in this article for high-quality development of characteristic towns.Using Delphi method and analytic hierarchy process,the indices selected based on experience were screened,and the evaluation indices retained were weighted.What's more,relevant suggestions for high-quality development of characteristic towns were put forward from the three aspects of production,living and ecology. 展开更多
关键词 Production-living-ecology integration Characteristic town High-quality development evaluation index
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Integrating multisource RS data and GIS techniques to assist the evaluation of resource-environment carrying capacity in karst mountainous area 被引量:8
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作者 PU Jun-wei ZHAO Xiao-qing +4 位作者 MIAO Pei-pei LI Si-nan TAN Kun WANG Qian TANG Wei 《Journal of Mountain Science》 SCIE CSCD 2020年第10期2528-2547,共20页
The karst mountainous area is an ecologically fragile region with prominent humanland contradictions.The resource-environment carrying capacity(RECC)of this region needs to be further clarified.The development of remo... The karst mountainous area is an ecologically fragile region with prominent humanland contradictions.The resource-environment carrying capacity(RECC)of this region needs to be further clarified.The development of remote sensing(RS)and geographic information system(GIS)provides data sources and processing platform for RECC monitoring.This study analyzed and established the evaluation index system of RECC by considering particularity in the karst mountainous area of Southwest China;processed multisource RS data(Sentinel-2,Aster-DEM and Landsat-8)to extract the spatial distributions of nine key indexes by GIS techniques(information classification,overlay analysis and raster calculation);proposed the methods of index integration and fuzzy comprehensive evaluation of the RECC by GIS;and took a typical area,Guangnan County in Yunnan Province of China,as an experimental area to explore the effectiveness of the indexes and methods.The results showed that:(1)The important indexes affecting the RECC of karst mountainous area are water resources,tourism resources,position resources,geographical environment and soil erosion environment.(2)Data on cultivated land,construction land,minerals,transportation,water conservancy,ecosystem services,topography,soil erosion and rocky desertification can be obtained from RS data.GIS techniques integrate the information into the RECC results.The data extraction and processing methods are feasible on evaluating RECC.(3)The RECC of Guangnan County was in the mid-carrying level in 2018.The midcarrying and low-carrying levels were the main types,accounting for more than 80.00%of the total study area.The areas with high carrying capacity were mainly distributed in the northern regions of the northwest-southeast line of the county,and other areas have a low carrying capacity comparatively.The coordination between regional resource-environment status and socioeconomic development is the key to improve RECC.This study explores the evaluation index system of RECC in karst mountainous area and the application of multisource RS data and GIS techniques in the comprehensive evaluation.The methods can be applied in related fields to provide suggestions for data/information extraction and integration,and sustainable development. 展开更多
关键词 Carrying capacity Multisource RS data GIS techniques evaluation index system Data integration Karst mountainous area Fuzzy comprehensive evaluation method
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Integrated Evaluation on Highway Engineering Geological Hazard in Mountainous Area of Enshi, Hubei 被引量:2
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作者 ZHAN Bin 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期901-904,共4页
Aiming at the geological features of highway engineering in mountainous area of Enshi, Hubei Province, the principles to set up an integrated evaluation system for highway engineering geological hazard are formulated.... Aiming at the geological features of highway engineering in mountainous area of Enshi, Hubei Province, the principles to set up an integrated evaluation system for highway engineering geological hazard are formulated. Then, the integrated evaluation system for highway engineering geological hazard in mountainous area of Enshi is established. In the evaluation system, the first-level evaluation indices are geological development degree, geological conditions, and damaging power, whereas the second-level indices including key factors affecting main kinds of geological hazard. Meanwhile, the borders of indices are determined. At last, the method of Fuzzy Comprehensive Evaluation (FCE) is adopted to quantitatively evaluate the highway engineering geological hazard in mountainous area of Enshi. 展开更多
关键词 highway in mountainous area geological hazard integrated evaluation fuzzy comprehensive evaluation
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Evaluation of the Added Value of Probabilistic Nowcasting Ensemble Forecasts on Regional Ensemble Forecasts
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作者 Lu YANG Cong-Lan CHENG +4 位作者 Yu XIA Min CHEN Ming-Xuan CHEN Han-Bin ZHANG Xiang-Yu HUANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第5期937-951,共15页
Ensemble forecasting systems have become an important tool for estimating the uncertainties in initial conditions and model formulations and they are receiving increased attention from various applications.The Regiona... Ensemble forecasting systems have become an important tool for estimating the uncertainties in initial conditions and model formulations and they are receiving increased attention from various applications.The Regional Ensemble Prediction System(REPS),which has operated at the Beijing Meteorological Service(BMS)since 2017,allows for probabilistic forecasts.However,it still suffers from systematic deficiencies during the first couple of forecast hours.This paper presents an integrated probabilistic nowcasting ensemble prediction system(NEPS)that is constructed by applying a mixed dynamicintegrated method.It essentially combines the uncertainty information(i.e.,ensemble variance)provided by the REPS with the nowcasting method provided by the rapid-refresh deterministic nowcasting prediction system(NPS)that has operated at the Beijing Meteorological Service(BMS)since 2019.The NEPS provides hourly updated analyses and probabilistic forecasts in the nowcasting and short range(0-6 h)with a spatial grid spacing of 500 m.It covers the three meteorological parameters:temperature,wind,and precipitation.The outcome of an evaluation experiment over the deterministic and probabilistic forecasts indicates that the NEPS outperforms the REPS and NPS in terms of surface weather variables.Analysis of two cases demonstrates the superior reliability of the NEPS and suggests that the NEPS gives more details about the spatial intensity and distribution of the meteorological parameters. 展开更多
关键词 integration ensemble nowcasting probabilistic prediction evaluation and verification
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A new method to evaluate integrated production system capacity in oil fields
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作者 YADUA Asekhame U. LAWAL Kazeem A. 《Petroleum Exploration and Development》 SCIE 2023年第3期665-674,共10页
To improve the design and management of an integrated production system(IPS),a set of mathematical models and workflows are developed for evaluating the capacity of an IPS at steady-state conditions.Combining the cons... To improve the design and management of an integrated production system(IPS),a set of mathematical models and workflows are developed for evaluating the capacity of an IPS at steady-state conditions.Combining the conservation laws with applicable multiphase fluid and choke models,these mathematical models are solved to characterize the hydraulics of an integrated system of reservoir,wells,chokes,flowlines,and separator at steady state.The controllable variables such as well count,choke size and separator pressure are adjusted to optimize the performance of the IPs at a specific time.It is found that increasing the well count can increase the bulk flow rate of the production network,but too many wells may increase the manifold pressure,leading to decline of single-well production.Increasing the choke size can improve the capacity of the IPs.The production of the IPs is negatively correlated with the separator pressure.With increasing separator pressure and decreasing choke size,the increment of total fluid production(the capacity of IPS)induced by increasing well count decreases.Validation tests with field examples show a maximum absolute deviation is 1.5%,demonstrating the robustness and validity of the proposed mathematical models and workflows. 展开更多
关键词 integrated production system modelling integrated production system capacity productivity evaluation production optimization nodal analysis
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Research and application of sidewall stability predic-tion method based on analytic hierarchy process and fuzzy integrative evaluation method 被引量:2
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作者 Bin Liu Fanjun Kong 《Natural Science》 2012年第2期142-147,共6页
As a difficult problem, sidewall instability has been beset drilling workers all the time. Not only does it cause huge economic losses, but also it determines the success or failure of drilling engineering. Due to com... As a difficult problem, sidewall instability has been beset drilling workers all the time. Not only does it cause huge economic losses, but also it determines the success or failure of drilling engineering. Due to complex relationship between various factors which influence sidewall stability, it hasn’t been found a widely applied method to predicate sidewall stability so far. Therefore, in order to formulate corresponding measures to ensure successful drilling, searching for a kind of better method to forecast sidewall stability before drilling becomes an imperative and significant topic for drilling engineering. On the basis of traditional sidewall stability analytical method, we have put forward the Fuzzy Comprehensive Evaluation Method to forecast sidewall stability regulation using physico-chemical performance parameters of the clay mineral. This method has been improved by introducing the Analytic Hierarchy Process (AHP) and the Maximum Subjection Principle in the application process. After introducing Analytic Hierarchy Process to identify weight, and Maximum Subjection Principle to obtain evaluation results, it has reduced the influence of human factors and enhanced the accuracy of the fuzzy evaluation results. The application in Hailaer Area indicates that this method can predict sidewall stability of gas-oil well with high credibility and strong practicability. 展开更多
关键词 Instability of SIDEWALL Forecast Fuzzy integrATIVE evaluation METHOD ANALYTIC HIERARCHY Process Maximum SUBJECTION Principle
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Integrated energy efficiency evaluation of a multi-source multi-load desalination micro-energy network 被引量:1
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作者 Dan Wang Jiancheng Yu +3 位作者 Bo Liu Chao Long Peiyu Chen Zhiqiang Chong 《Global Energy Interconnection》 2020年第2期128-139,共12页
With increasing global shortage of fresh water resources,many countries are prioritizing desalination as a means of utilizing abundantly available seawater resources.Integrated energy efficiency evaluation is a scient... With increasing global shortage of fresh water resources,many countries are prioritizing desalination as a means of utilizing abundantly available seawater resources.Integrated energy efficiency evaluation is a scientific method for the quantitative analysis of energy efficiency based on multiple indicators and is very useful for investment,construction,and scientific decision-making for desalination projects.In this paper,the energy efficiency evaluation of the micro energy network (MEN) of desalination for multi-source and multi-load is studied,and the basic idea of comprehensive energy efficiency evaluation is analyzed.The process includes the use of a MEN model to establish an integrated energy efficiency evaluation index system,taking into consideration energy,equipment,economic,environmental,and social factors.A combined evaluation method considering subjective and objective comprehensive weights for multi-source multi-load desalination MENs is proposed to evaluate the energy efficiency of desalination and from multiple perspectives. 展开更多
关键词 Seawater Desalination Micro-energy Network integrated Energy Efficiency evaluation Index System evaluation Method
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Integrated Evaluation of Ecological Security at Different Scales Using Remote Sensing: A Case Study of Zhongxian County, the Three Gorges Area, China 被引量:27
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作者 ZUO Wei ZHOU Hui-Zhen +3 位作者 ZHU Xiao-Hua WANG Qiao WANG Wen-Jie WU Xiu-Qin 《Pedosphere》 SCIE CAS CSCD 2005年第4期456-464,共9页
Based on related literature and this research, an ecological security evaluation from the pixel scale to the small watershed or county scale was presented using remote sensing data and related models. With the driver-... Based on related literature and this research, an ecological security evaluation from the pixel scale to the small watershed or county scale was presented using remote sensing data and related models. With the driver-pressure, state and exposure to pollution-response (DPSER) model as a basis, a conceptual framework of regional ecological evaluation and an index system were established. The extraction and standardization of evaluation indices were carried out with GIS techniques, an information extraction model and a data standardization model. The conversion of regional ecological security results from the pixel scale to a small watershed or county scale was obtained with an evaluation model and a scaling model. Two conceptual scale conversion models of regional ecological security from the pixel scale to the county scale were proposed: 1) scale conversion of ecological security regime results from pixel to small watershed; and 2) scale conversion from pixel to county. These research results could provide useful ideas for regional ecological security evaluation as well as ecological and environmental management. 展开更多
关键词 中国 山谷 遥感技术 生态安全 生态系统
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Geometric Conversion Approach for the Numerical Evaluation of Hypersin gular and Nearly Hypersingular Boundary Integrals over Curved Surface Boundary Elements
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作者 马杭 《Journal of Shanghai University(English Edition)》 CAS 2002年第2期101-110,共10页
With the aid of the properties of the hypersingular kernels, a geometric conversion approach was presented in this paper. The conversion leads to a general approach for the accurate and reliable numerical evaluation o... With the aid of the properties of the hypersingular kernels, a geometric conversion approach was presented in this paper. The conversion leads to a general approach for the accurate and reliable numerical evaluation of the hypersingular surface boundary integrals encountered in a variety of applications with boundary element method. Based on the conversion, the hypersingularity in the boundary integrals could be lowered by one order, resulting in the simplification of the computer code. Moreover, an integral transformation was introduced to damp out the nearly singular behavior of the kernels by the distance function defined in the local polar coordinate system for the nearly hypersingular case. The approach is simple to use, which can be inserted readily to computer code, thus getting rid of the dull routine deduction of formulae before the numerical implementations, as the expressions of these kernels are in general complicated. The numerical examples were given in three dimensional elasticity, verifying the effectiveness of the proposed approach, which makes it possible to observe numerically the behavior of the boundary integral values with hypersingular kernels across the boundary. 展开更多
关键词 boundary element method numerical evaluation hypersingular boundary integral nearly hypersingular boundary integral geometric conversion.
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Numerical Evaluation of CPV Boundary Integrals with Symmetrical Quadrature Schemes
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作者 马杭 徐凯宇 《Journal of Shanghai University(English Edition)》 CAS 2003年第1期28-34,共7页
Stemming from the definition of the Cauchy principal values (CPV) integrals, a newly developed symmetrical quadrature scheme was proposed in the paper for the accurate numerical evaluation of the singular boundary int... Stemming from the definition of the Cauchy principal values (CPV) integrals, a newly developed symmetrical quadrature scheme was proposed in the paper for the accurate numerical evaluation of the singular boundary integrals in the sense of CPV encountered in the boundary element method. In the case of inner element singularities, the CPV integrals could be evaluated in a straightforward way by dividing the element into the symmetrical part and the remainder(s). And in the case of end singularities, the CPV integrals could be evaluated simply by taking a tangential distance transformation of the integrand after cutting out a symmetrical tiny zone around the singular point. In both cases, the operations are no longer necessary before the numerical implementation, which involves the dull routine work to separate out singularities from the integral kernels. Numerical examples were presented for both the two and the three dimensional boundary integrals in elasticity. Comparing the numerical results with those by other approaches demonstrates the feasibility and the effectiveness of the proposed scheme. 展开更多
关键词 boundary element method(BEM) singular boundary integral symmetrical integration distance transformation numerical evaluation.
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An integrated approach to evaluation on ecological service functions for urban green space and its application
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作者 Hu Dan,Wang Ru songResearch Center for Eco Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第3期61-69,共9页
This methodological investigation deals with measurement and valuation of ecological service functions for urban green space. Social, economic and ecological dimensions for such types of function were analyzed and a ... This methodological investigation deals with measurement and valuation of ecological service functions for urban green space. Social, economic and ecological dimensions for such types of function were analyzed and a concept “integrated ecological service functions” (IESF) was put forward for evaluation. Based upon this conceptual approach, an index system for measuring IESF for urban green space was established. With a methodological integration of fuzzy mathematics, decision making analysis and Delphi method, an AHP fuzzy evaluation techniques for IESF for urban green space, called AFIFUG method, was developed. Such a method has been directly applied to the land use strategic planning of Tianjin out ring green belt(TOGB), and its analysis results have been successfully put into operation. 展开更多
关键词 ecological evaluation integrated ecological service functions urban green space.
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Integrated evaluation system under randomness and fuzziness for groundwater contamination risk assessment in a little town, Central China 被引量:2
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作者 祝慧娜 袁兴中 +4 位作者 梁婕 刘永德 尹娟 江洪炜 黄华军 《Journal of Central South University》 SCIE EI CAS 2014年第3期1044-1050,共7页
An integrated evaluation system under randomness and fuzziness was developed in this work to systematically assess the risk of groundwater contamination in a little town, Central China. In this system, randomness of t... An integrated evaluation system under randomness and fuzziness was developed in this work to systematically assess the risk of groundwater contamination in a little town, Central China. In this system, randomness of the parameters and the fuzziness of the risk were considered simultaneously, and the exceeding standard probability of contamination and human health risk due to the contamination were integrated. The contamination risk was defined as a combination of "vulnerability" and "hazard". To calculate the value of "vulnerability", pollutant concentration was simulated by MODFLOW with random input variables and a new modified health risk assessment(MRA) model was established to analyze the level of "hazard". The limit concentration based on environmental-guideline and health risk due to manganese were systematically examined to obtain the general risk levels through a fuzzy rule base. The "vulnerability" and "hazard" were divided into five categories of "high", "medium-high", "medium", "low-medium" and "low", respectively. Then, "vulnerability" and "hazard" were firstly combined by integrated evaluation. Compared with the other two scenarios under deterministic methods, the risk obtained in the proposed system is higher. This research illustrated that ignoring of uncertainties in evaluation process might underestimate the risk level. 展开更多
关键词 模糊综合评价系统 健康风险评估 综合评价体系 地下水污染 随机性 小城镇 中国 MODFLOW
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Supplier Evaluation Model Based on Fuzzy Measures and Choquet Integral
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作者 武建章 张强 桑圣举 《Journal of Beijing Institute of Technology》 EI CAS 2010年第1期109-114,共6页
To identify interactions among evaluation criteria and describe their importance,a new identification method making use of a fuzzy measure is presented.The relative weight and interaction degree of every evaluation cr... To identify interactions among evaluation criteria and describe their importance,a new identification method making use of a fuzzy measure is presented.The relative weight and interaction degree of every evaluation criteria pair are obtained by using the diamond pairwise comparison method.Based on comparison results,the maximum eigenvector method of analytic hierarchy process (AHP),the hierarchical clustering method,and the phi(s) transformation are utilized to generate values of the fuzzy measure for each subset of the evaluation criterion set.Overall evaluation on each supplier is aggregated by Choquet integral with respect to the fuzzy measure.Finally,an illustrative example demonstrates the practical feasibility and validity of the proposed method. 展开更多
关键词 fuzzy measure Choquet integral diamond pairwise comparison phi(s) transformation supplier evaluation
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DECIDING PRODUCTION TECHNIQUE STRATEGY BY INTEGRAL EVALUATION 被引量:1
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作者 赵景礼 吴健 富强 《Journal of Coal Science & Engineering(China)》 1997年第2期91-96,共6页
According to overall mean square root of weighted deviation, a significant method of selecting coal mine production technique strategy has been put forward in this paper. In the given example, an index system of evalu... According to overall mean square root of weighted deviation, a significant method of selecting coal mine production technique strategy has been put forward in this paper. In the given example, an index system of evaluating different mining methods has also been provided, which plays a guiding effect in production of coal mine. 展开更多
关键词 煤矿 技术战略 整体评价 地质条件 经济效益
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Application of fuzzy integrated evaluation in the safety of coal industry of China 被引量:1
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作者 刘伟 陶树人 《Journal of Coal Science & Engineering(China)》 2005年第1期102-105,共4页
Based on fuzzy integrated evaluation theory, the safety of coal industry was analyzed, the factors affecting the safety of coal industry was considered, and its fuzzy in- tegrated estimating theory and results were gi... Based on fuzzy integrated evaluation theory, the safety of coal industry was analyzed, the factors affecting the safety of coal industry was considered, and its fuzzy in- tegrated estimating theory and results were given. Finally this paper proposed a new method of industry safety estimation. According to this method, we can integrate the fac- tors affecting coal industry and deal with the parameters and targets of evaluating factors by quantitative analysis, thus give a scientific and reasonable safety degree analyzing evaluation. 展开更多
关键词 煤炭工业 中国 安全评价 模糊分析 市场效应
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Structural integrity evaluation of irradiated LEU targets for the production of molybdenum‑99 using thermo‑mechanical behavior simulation coupled with pressure of fission gas release calculation
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作者 N.Mellel B.Mohammedi +3 位作者 M.Salhi M.Dougdag S.Missaoui S.Hanini 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第12期12-23,共12页
Irradiated low-enriched uranium as target plates is used to produce,via neutron radiation and from the molybdenum-99 fission product,technetium-99m,which is a radio-element widely used for diagnosis in the field of nu... Irradiated low-enriched uranium as target plates is used to produce,via neutron radiation and from the molybdenum-99 fission product,technetium-99m,which is a radio-element widely used for diagnosis in the field of nuclear medicine.The behavior of this type of target must be known to prevent eventual failures during radiation.The present study aims to assess,via prediction,the thermal–mechanical behavior,physical integrity,and geometric stability of targets under neutron radiation in a nuclear reactor.For this purpose,a numerical simulation using a three-dimensional finite element analysis model was performed to determine the thermal expansion and stress distribution in the target cladding.The neutronic calculation results,target material properties,and cooling parameters of the KAERI research group were used as inputs in our developed model.Thermally induced stress and deflection on the target were calculated using Ansys-Fluent codes,and the temperature profiles,as inputs of this calculation,were obtained from a CFD thermal–hydraulic model.The stress generated,induced by the pressure of fission gas release at the interface of the cladding target,was also estimated using the Redlich–Kwong equation of state.The results obtained using the bonded and unbonded target models considering the effect of the radiation heat combined with a fission gas release rate of approximately 3%show that the predicted thermal stress and deflection values satisfy the structural performance requirement and safety design.It can be presumed that the integrity of the target cladding is maintained under these conditions. 展开更多
关键词 Irradiated LEU target Mo-99 production integrity evaluation Thermo-mechanical analyses Fission gas pressure
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