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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
基金supported by the National Key Research and Development Project(2018YFB1700802)the National Natural Science Foundation of China(72071206)the Science and Technology Innovation Plan of Hunan Province(2020RC4046).
文摘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.
基金This project was supported by the Evaluate Quality of Satellite TT&C Mission(C0112)
文摘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.
基金Sponsored by Graduate Innovation Fund of Jiangxi Provincial Department of Education:Equalization of Countylevel Educational Facilities against the Background of New Urbanization--A Case Study of Nanchang City
文摘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.
基金supported by Humanities and Social Sciences Foundation of the Ministry of Education in China (12YJA790163)
文摘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.
基金Humanities and Social Science Project of Shandong Province(18ZCGL08)Science and Technology Development Plan of Tai'an City(2019ZC258)+1 种基金Youth Innovation Team Project for Talent Introduction and Cultivation in Universities of Shandong ProvinceSocial Science Planning and Research Project of Shandong Province(20CSDJ62).
文摘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.
基金the support given by the government and official in Guangnan Countyfunded by[National Natural Science Foundation of China]grant number[41361020,40961031]+3 种基金[Joint Fund of Yunnan Provincial Science and Technology Department and Yunnan University]grant number[2018FY001(-017)][Project of Innovative Talents Cultivation for Graduate Students of Yunnan University]grant number[C176230200][Project of Internationalization and Cultural Inheritance and Innovation of Yunnan University]grant number[C176250202][Science Research Fund of Yunnan Provincial Education Department in 2020:Postgraduate]grant number[2020Y0030]。
文摘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.
文摘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.
基金supported by National Key Research and Development Program of China(Grant No.2018YFC1506804)the Beijing Natural Science Foundation(Grant No.8222051)the Key Innovation Team of China Meteorological Administration(CMA2022ZD04)。
文摘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.
文摘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.
文摘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.
基金supported by the State Grid Corporation of China project titled “Study on Multisource and Multi-load Coordination and Optimization Technology Considering Desalination of Sea Water”(SGTJDK00DWJS1800011)
文摘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.
基金Project supported by the National Natural Science Foundation of China (No. 40301002) and the State EnvironmentalProtection Administration of China.
文摘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.
文摘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.
文摘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.
文摘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.
基金Projects(51039001,51009063) supported by the National Natural Science Foundation of ChinaProject(SX2010-026) supported by State Council Three Gorges Project Construction Committee Executive Office,China+1 种基金Project(2012BS046) supported by Henan University of Technology,ChinaProject(BYHGLC-2010-02) supported by the Guangzhou Water Authority,China
文摘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.
基金Sponsored by the National Natural Science Foundation of China(7047106370771010)
文摘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.
文摘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.
文摘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.
文摘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.