A comprehensive method to evaluate the factors affecting the production capacity of horizontal wells in Carboniferous volcanic rocks after fracturing is investigated.A systematic approach combining gray correlation an...A comprehensive method to evaluate the factors affecting the production capacity of horizontal wells in Carboniferous volcanic rocks after fracturing is investigated.A systematic approach combining gray correlation analysis,hierarchical analysis and fuzzy evaluation is proposed.In particular,first the incidence of reservoir properties and fracturing parameters on production capacity is assessed.These parameters include reservoir base geological parameters(porosity,permeability,oil saturation,waterproof height)as well as engineering parameters(fracture halflength,fracture height,fracture conductivity,fracture distance).Afterwards,a two-by-two comparison judgment matrix of sensitive parameters is constructed by means of hierarchical analysis,and the weighting coefficients of the factors are determined,where oil saturation,fracture conductivity and fracture half-length are weighted higher.Finally,the horizontal wells in the target block are categorized in terms of production capacity based on the fuzzy evaluation method,and split accordingly into high-producing,relatively high-producing,medium-producing and low-producing wells.Such a categorization is intended to provide parametric guidance for reservoir fracturing and modification.展开更多
The proper selection of a relevant mixer generally requires an effective assessment of several models against theapplication requirements. This is a complex task, as traditional evaluation methods generally focus only...The proper selection of a relevant mixer generally requires an effective assessment of several models against theapplication requirements. This is a complex task, as traditional evaluation methods generally focus only on a single aspect of performance, such as pressure loss, mixing characteristics, or heat transfer. This study assesses aurea-based selective catalytic reduction (SCR) system installed on a ship, where the installation space is limitedand the distance between the urea aqueous solution injection position and the reactor is low;therefore, the staticmixer installed in this pipeline has special performance requirements. In particular, four evaluation indices areused in this study: The B value, C value, pressure loss correction factor (Z′), and the ratio of the required distanceto the equivalent diameter of the pipe (LV/D) when the velocity field after the mixer attains uniformity. Six typesof static mixers were simulated with varying concentrations, flow speeds, and positions. A fuzzy comprehensiveevaluation method was introduced to evaluate and compare the related advantages and disadvantages. The resultsshowed that 1) mixing performance was related to the shape of the mixer and had no direct relationship with flowvelocity. 2) For the same mixer position, the lower the urea concentration, the greater the difficulty of evenly mixing the solution. 3) At a constant urea concentration, the mixing performance improved when the mixer was closer to the injection inlet. 4) The installation of a GK mixer in the SCR system of a 9L20C diesel engine was best.展开更多
As the core of the rocket system,the performance and quality of rocket engines are of paramount impor-tance.Currently,the production of aerospace model rocket engines does not differentiate the production and selectio...As the core of the rocket system,the performance and quality of rocket engines are of paramount impor-tance.Currently,the production of aerospace model rocket engines does not differentiate the production and selection of motors according to the importance of the mission,which is insufficient to ensure the high reliability requirements of important launch missions.To select rocket engines with better performance quality for more critical launch missions,this paper uses fuzzy comprehensive evaluation and TOPSIS methods based on the test value or assessment informa-tion of evaluation indicators.The method scientifically and accurately ranks the performance quality of rocket engines,choosing the engines with better performance quality for more strategic missions,and providing technical support for national management decisions.展开更多
A quantitative and comprehensive method of product life cycle assessment(LCA) with fuzzy theory is developed, which will help designers to select the optimum design scheme for product life cycle design(LCD). Based on ...A quantitative and comprehensive method of product life cycle assessment(LCA) with fuzzy theory is developed, which will help designers to select the optimum design scheme for product life cycle design(LCD). Based on the theory of multiple attribute decision making, an algorithm of comprehensive and comparative evaluation for product environmental adaptability is presented. A program is built and used in an example of design improvement. The result shows that the proposed method and algorithm are practical and effective to the development of green products.展开更多
[Objective] The aim was to propose a new entropy weight fuzzy compre- hensive evaluation method for assessing cotton salt tolerance, realizing the objective, accurate and comprehensive evaluation of salt tolerance of ...[Objective] The aim was to propose a new entropy weight fuzzy compre- hensive evaluation method for assessing cotton salt tolerance, realizing the objective, accurate and comprehensive evaluation of salt tolerance of cotton. [Method] A sand culture experiment under salt stress of 150 mmol/L of NaCI was designed. The in- dicator weight was determined with the entropy weight fuzzy comprehensive evalu- ation method, based on the salt injury index of indicators. The salt tolerance of cotton was evaluated comprehensively. [Result] At the germination stage, the entropy and weight of salt injury index of germination energy, vigor index, hypocotyl length and fresh weight were highest, followed by germination rate and germination index, and of root length were lowest. At the seedling stage, the entropy and weight of salt injury index of plasma membrane permeability, root vigor and leaf expansion rate were highest, followed by plant height and net photosynthetic rate, and of shoot dry weight and root dry weight were lowest. The salt tolerance of cotton differed a- mong growth stages and cultivars. Among the 11 cultivars, CCRI-44 and CCRI-75 were steadily salt-tolerant at both germination and seedling stages; CCRI-17, Sumi- an 22, Sumian 15 and Dexiamianl had a stable moderate salt tolerance; while Sumian 12 and Simian 3 were steadily salt-sensitive. [Conclusion] The evaluated result was objective and exact, which indicated that this method could be used in comprehensive evaluation of salt tolerance of cotton.展开更多
The aquaculture pond water quality was taken as research objects,based on the general analysis of factors influencing the pond water quality,the system of index estimation and assessment standard were established afte...The aquaculture pond water quality was taken as research objects,based on the general analysis of factors influencing the pond water quality,the system of index estimation and assessment standard were established after sorting by importance of the factors by means of Delphi and expert investigation.In this study,index weight was confirmed according to the importance of the factors and relative membership grade of the measured values,thus and the fuzzy comprehensive evaluation model of aquaculture pond water quality was constructed,and the fuzzy comprehensive evaluation system of freshwater aquaculture pond water quality was designed and implemented.The application of this system in the assessment of aquaculture pond water quality by a company had achieved better result.展开更多
[Objective] This study was to provide references for the evaluation of water quality in aquaculture ponds by evaluating the pond water quality using fuzzy comprehensive evaluation method based on entropy weight. [Meth...[Objective] This study was to provide references for the evaluation of water quality in aquaculture ponds by evaluating the pond water quality using fuzzy comprehensive evaluation method based on entropy weight. [Method] The fuzzy compre- hensive evaluation method based on entropy weight was used to evaluate the water quality in the ponds with Ukraine scale carp （Cyprinus carpio） as the main cultivated fish. The average size of the fish was 71.4 g/ind, and totally three groups of pond were set with the population density of 6 000, 9 000, 12 000 ind/hm2. [Result] According to the GB3838-2002 Environmental Quality Standards for Surface Water of China, the water quality of 6 000 ind/hm2 group was Grade I, and the water quality of 9 000 and 12 000 ind/hm2 were Grade V. [Conclusion] With the increasing of feeding density, the pond water quality would worsen, however, there is no difference on water quality between 9 000 and 12 000 ind/hm2 groups.展开更多
The paper analyzes the factors influencing machine tool selection. By using fuzzy mathematics theory, we establish a theorietical model for optimal machine tool selection considering geometric features, clamping size,...The paper analyzes the factors influencing machine tool selection. By using fuzzy mathematics theory, we establish a theorietical model for optimal machine tool selection considering geometric features, clamping size, machining range, machining precision and surface roughness. By means of fuzzy comprehensive evaluation method, the membership degree of machine tool selection and the largest comprehensive evaluation index are determined. Then the reasonably automatic selection of machine tool is realized in the generative computer aided process planning （CAPP） system. Finally, the finite element model based on ABAQUS is established and the cutting process of machine tool is simulated. According to the theoretical and empirical cutting parameters and the curve of surface residual stress, the optimal cutting parameters can be determined.展开更多
In this paper, traffic environment quality assessment is achieved by applying fuzzy mathematics methods. Set up an assessment system, determine assessment criterion, formulate membership function, make program designs...In this paper, traffic environment quality assessment is achieved by applying fuzzy mathematics methods. Set up an assessment system, determine assessment criterion, formulate membership function, make program designs and conduct example analysis. The evaluation result is consistent with the real case. So that the method of the fuzzy evaluation is a good one for the environment quality assessment.展开更多
Climate change and economic development impact the population expansion and water shortage in the middle reaches of the Yangtze River Basin(MYRB),leading directly to drought aggravation-expansion and impacting agricul...Climate change and economic development impact the population expansion and water shortage in the middle reaches of the Yangtze River Basin(MYRB),leading directly to drought aggravation-expansion and impacting agricultural production in the MYRB.Therefore,this study quantitatively evaluated agricultural drought vulnerability in the MYRB based on the variable fuzzy evaluation model(VFEM).The main conclusions are as follows:(1)The arable land in the MYRB gradually decreased between 2005 and 2020,whereas the forest cover decreased and then increased;(2)precipitation and evapotranspiration were the key factors affecting the agricultural drought vulnerability(e.g.,weights of 0.24 and 0.21),whereas arable land density and gross domestic product(GDP)per capita played less significant roles;and(3)the agricultural drought vulnerability in the MYRB during 2005-2020 was mainly at level 3 and below,with higher drought vulnerability in the western and northern regions,which had a higher drought risk potential.展开更多
Flexible interconnection devices(FIDs)significantly enhance the regulation and management of complex power flows in distribution networks.Voltage source converter(VSC)-based FIDs,in particular,are pivotal for increasi...Flexible interconnection devices(FIDs)significantly enhance the regulation and management of complex power flows in distribution networks.Voltage source converter(VSC)-based FIDs,in particular,are pivotal for increasing system reliability and operational efficiency.These devices are crucial in supporting the extensive incorporation of electric vehicles(EVs)and renewable energy sources(RESs)into new,load-centric environments.This study evaluates four unique FID-based configurations for distribution network interconnections,revealing their distinctive features.We developed a comprehensive evaluation framework and tool by integrating the analytic hierarchy process(AHP)and fuzzy comprehensive evaluation(FCE),which includes five key performance indicators to assess these configurations.The study identifies the optimal application scenarios for each configuration and discusses their roles in enabling the seamless integration of EVs and RESs.The findings provide essential insights and guidelines for the design and implementation of adaptable,interconnected distribution networks that are equipped to meet the growing demands of future urban environments.展开更多
The glacial lake in the Boqu Basin in Tibetan Plateau has changed significantly in recent years due to global warming,seriously affecting the natural and social environments in downstream areas.We obtained the change ...The glacial lake in the Boqu Basin in Tibetan Plateau has changed significantly in recent years due to global warming,seriously affecting the natural and social environments in downstream areas.We obtained the change characteristics of glacial lakes by analyzing remote sensing images and evaluated the outburst floods susceptibility of glacial lakes in the Boqu Basin by combining fuzzy mathematics and random forest methods.An empirical formula for glacial lake hazard evaluation was established based on a fuzzy comprehensive evaluation.The confusion matrix were used to assess the evaluation effect of each method.The conclusions were as follows:(1)Under the influence of climate warming,glaciers are retreating further from the glacial lakes,and the size of glaciers that can impact these lakes is shrinking.Geological conditions,such as steep slopes around the lakes,have replaced glacier tongues as the primary factors threatening the susceptibility of the glacial lakes;(2)Among the three evaluation methods,the empirical formula offers high calculation accuracy and is the most convenient to use,which provides an accuracy rate of 85.71%in susceptibility evaluation of the Boqu Basin glacial lake and can be applied to other areas in the rapid evaluation of the susceptibility of glacial lakes;(3)The impact analysis of the collapse shows that the collapse of the Galongco fault would cause large economic losses.展开更多
A task allocation problem for the heterogeneous unmanned aerial vehicle (UAV) swarm in unknown environments is studied in this paper.Considering that the actual mission environment information may be unknown,the UAV s...A task allocation problem for the heterogeneous unmanned aerial vehicle (UAV) swarm in unknown environments is studied in this paper.Considering that the actual mission environment information may be unknown,the UAV swarm needs to detect the environment first and then attack the detected targets.The heterogeneity of UAVs,multiple types of tasks,and the dynamic nature of task environment lead to uneven load and time sequence problems.This paper proposes an improved contract net protocol (CNP) based task allocation scheme,which effectively balances the load of UAVs and improves the task efficiency.Firstly,two types of task models are established,including regional reconnaissance tasks and target attack tasks.Secondly,for regional reconnaissance tasks,an improved CNP algorithm using the uncertain contract is developed.Through uncertain contracts,the area size of the regional reconnaissance task is determined adaptively after this task assignment,which can improve reconnaissance efficiency and resource utilization.Thirdly,for target attack tasks,an improved CNP algorithm using the fuzzy integrated evaluation and the double-layer negotiation is presented to enhance collaborative attack efficiency through adjusting the assignment sequence adaptively and multi-layer allocation.Finally,the effectiveness and advantages of the improved method are verified through comparison simulations.展开更多
For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. Th...For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. The coefficient of variation of each indicator is used to determine the weight instead of traditional calculating superscales method. On the other hand, fuzzy matter-elements are constructed, and normal membership degrees are used instead of traditional trapezoidal ones. The composite fuzzy matter-elements with associated coefficient are constructed through associated transformation. The levels of natural water quality are determined according to the principle of maximum correlation. The improved fuzzy matter-element evaluation method is applied to evaluate water quality of the Luokou mainstream estuary at the first ten weeks in 2011 with the coefficient of variatiola method determining the weights. Water quality of Luokou mainstream estuary is dropping from level I to level II. The results of the improved evaluation method are basically the same as the official water quality. The variation coefficient method can reduce the workload, and overcome the adverse effects from abnormal values, compared with the traditional calculating superscales method. The results of improved fuzzy matter- element evaluation method are more credible than the ones of the traditional evaluation method. The improved evaluation method can use information of monitoring data more scientifically and comprehensively, and broaden a new evaluation method for water quality assessment.展开更多
This paper explores the method of comprehensive evaluation of water resources carrying capacity and sets up an evaluation model applying the fuzzy comprehensive evaluation method. Based on the data of nature,society,e...This paper explores the method of comprehensive evaluation of water resources carrying capacity and sets up an evaluation model applying the fuzzy comprehensive evaluation method. Based on the data of nature,society,economics and water resources of the Tarim River Basin in 2002,we evaluated the water resources carrying capacity of the basin by means of the model. The results show that the comprehensive grades are 0.438 and 0.454 for Aksu and Kashi prefectures respectively,where the current water resources exploitation and utilization has reached a relative high degree and there is only a very limited water carrying capacity,0.620 for Kizilsu Kirgiz Autonomous Prefecture,where water resources carrying capacity is much higher,and in between for Hotan Prefecture and Bayingolin Mongo-lian Autonomous Prefecture. As a whole,the comprehensive grade of the Tarim River Basin is 0.508 and the current water resources exploitation and utilization has reached a relative high degree. Thus,we suggest that the integrated management of the water resources in the basin should be strengthened in order to utilize water resources scientifically and sustainably.展开更多
In order to improve the effectiveness of Fuzzy Synthetic Evaluation (FSE) models, a Parameter Correlation Analysis (PCA) was introduced into the FSE and a case study was carried out in the Naoli River in the Sanjiang ...In order to improve the effectiveness of Fuzzy Synthetic Evaluation (FSE) models, a Parameter Correlation Analysis (PCA) was introduced into the FSE and a case study was carried out in the Naoli River in the Sanjiang Plain, Northeast China. The basic principle of the PCA is that the pairs of parameters which are highly correlated and linear with each other would contribute the same information to an assessment and one of them should be eliminated. The method of the PCA is that a correlation relationship among candidate parameters is examined before the FSE. If there is an apparent nonlinear or curvilinear relationship between two parameters, then both will be retained; if the correlation is significant (p<0.01), and the scatter plot suggests a linear relationship, then one of them will be deleted. However, which one will be deleted? For solving this problem, a sensitivity test was conducted and the higher sensitivity parameters remained. The results indicate that the original data should be preprocessed through the PCA for redundancy and variability. The study shows that introducing the PCA into the FSE can simplify the FSE calculation process greatly, while the results have not been changed much.展开更多
A slope stability evaluation method is proposed combining group decision theory,the analytic hierarchy process and fuzzy comprehensive evaluation.The index weight assignment of each evaluation element is determined by...A slope stability evaluation method is proposed combining group decision theory,the analytic hierarchy process and fuzzy comprehensive evaluation.The index weight assignment of each evaluation element is determined by group decision theory and the analytic hierarchy process,and the membership degree of each indicator is determined based on fuzzy set theory.According to the weights and memberships,the membership degrees of the criterion layer are obtained by fuzzy operations to evaluate the slope stability.The results show that(1)the evaluation method comprehensively combines the effects of multiple factors on the slope stability,and the evaluation results are accurate;(2)the evaluation method can fully leverage the experience of the expert group and effectively avoid evaluation errors caused by the subjective bias of a single expert;(3)based on a group decision theory entropy model,this evaluation method can quantitatively evaluate the reliability of expert decisions and effectively improve the efficiency of expert group discussion;and(4)the evaluation method can transform the originally fuzzy and subjective slope stability evaluation into a quantitative evaluation.展开更多
Using soil data of the Second National Field Survey,the soil fertility of wetland ecosystem of Dongting Lake was evaluated by using the technology of GIS and method of fuzzy evaluation.Integrated with the wetland actu...Using soil data of the Second National Field Survey,the soil fertility of wetland ecosystem of Dongting Lake was evaluated by using the technology of GIS and method of fuzzy evaluation.Integrated with the wetland actuality of Dongting Lake and particularity of paddy,seven factors (including soil organic matter,total nitrogen,total phosphorus,total potassium,available phosphorus,available potassium,and pH value),closely related with soil fertility,were chosen to establish the index system of synthetical evaluation.Based on the effect degree of each selected index on soil fertility,a judgment matrix was built,and the weight coefficient was determined by the method of correlation coefficient.Finally,under the support of the spatial analysis module of GIS (Geographic Information System),the spatial distribution properties of soil fertility in wetland ecosystem of Dongting Lake were studied.The results show that the soil fertility of Dongting Lake wetland ecosystem is not very good,and the area of type III and type IV achieves 69.8%.As a result,many countermeasures should be taken to improve the soil fertility.As for the spatial properties,the soil fertility level of central and west Dongting Lake is much higher than that of north and south part.The soil fertility of paddy field surpasses that of red soil,and the contents of soil organic matter and total nitrogen in paddy field are large.展开更多
Drilling engineering has great uncertainty and it always involves huge investment and high risk. Risk analysis of extended reach drilling （ERD） is very important to prevent complex failures and to improve drilling e...Drilling engineering has great uncertainty and it always involves huge investment and high risk. Risk analysis of extended reach drilling （ERD） is very important to prevent complex failures and to improve drilling efficiency. Nowadays there are few reports on how to analyze quantitatively the drilling risk for extended reach wells （ERWs）. Based on the fuzzy set theory, a comprehensive fuzzy evaluation model for analyzing risks of ERD is proposed in this paper. Well B6ERW07 is a planned 8,000-meter ERW with a high ratio of horizontal displacement （HD） to vertical depth （VD） in the Liuhua Oilfield, the South China Sea, China. On the basis of the evaluation model developed in this study, the risk for drilling Well B6ERW07 was evaluated before drilling. The evaluation result shows that the success rate of drilling this well is predicted to be 51.9%, providing important rational and scientific information for the decisionmakers.展开更多
The Changjiang River (Yangtze) is one of the fastest growth areas of container transportation in China. Rail, road and water transportation have competed against each other for container transportation in the Chang-ji...The Changjiang River (Yangtze) is one of the fastest growth areas of container transportation in China. Rail, road and water transportation have competed against each other for container transportation in the Chang-jiang River main line and its delta area. It is of significance to assess these different transportation modes scientifically in order to organize container transportation efficiently in this area and make decision for integral plan and construction of transportation system in this area. This paper outlines application of fuzzy comprehensive evaluation to appraise different modes of typical direction of containers. Twelve assessment indexes were decided. Membership functions were formulated. Evaluation results indicated that road transportation was optimal mode in the Changjiang River delta area, however water transportation was the primary way in the Changjiang River main line.展开更多
基金Natural Science Foundation of China(NSFC),Grant No.52404016(Lijuan Huang)Natural Science Foundation of Hubei Province,Grant No.2024AFB322(Lijuan Huang)Open Fund of Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering(Yangtze University),Grant No.YQZC202405(Lijuan Huang).
文摘A comprehensive method to evaluate the factors affecting the production capacity of horizontal wells in Carboniferous volcanic rocks after fracturing is investigated.A systematic approach combining gray correlation analysis,hierarchical analysis and fuzzy evaluation is proposed.In particular,first the incidence of reservoir properties and fracturing parameters on production capacity is assessed.These parameters include reservoir base geological parameters(porosity,permeability,oil saturation,waterproof height)as well as engineering parameters(fracture halflength,fracture height,fracture conductivity,fracture distance).Afterwards,a two-by-two comparison judgment matrix of sensitive parameters is constructed by means of hierarchical analysis,and the weighting coefficients of the factors are determined,where oil saturation,fracture conductivity and fracture half-length are weighted higher.Finally,the horizontal wells in the target block are categorized in terms of production capacity based on the fuzzy evaluation method,and split accordingly into high-producing,relatively high-producing,medium-producing and low-producing wells.Such a categorization is intended to provide parametric guidance for reservoir fracturing and modification.
基金wasfinancially aided by the National Natural Science Foundation of China(52276122).
文摘The proper selection of a relevant mixer generally requires an effective assessment of several models against theapplication requirements. This is a complex task, as traditional evaluation methods generally focus only on a single aspect of performance, such as pressure loss, mixing characteristics, or heat transfer. This study assesses aurea-based selective catalytic reduction (SCR) system installed on a ship, where the installation space is limitedand the distance between the urea aqueous solution injection position and the reactor is low;therefore, the staticmixer installed in this pipeline has special performance requirements. In particular, four evaluation indices areused in this study: The B value, C value, pressure loss correction factor (Z′), and the ratio of the required distanceto the equivalent diameter of the pipe (LV/D) when the velocity field after the mixer attains uniformity. Six typesof static mixers were simulated with varying concentrations, flow speeds, and positions. A fuzzy comprehensiveevaluation method was introduced to evaluate and compare the related advantages and disadvantages. The resultsshowed that 1) mixing performance was related to the shape of the mixer and had no direct relationship with flowvelocity. 2) For the same mixer position, the lower the urea concentration, the greater the difficulty of evenly mixing the solution. 3) At a constant urea concentration, the mixing performance improved when the mixer was closer to the injection inlet. 4) The installation of a GK mixer in the SCR system of a 9L20C diesel engine was best.
文摘As the core of the rocket system,the performance and quality of rocket engines are of paramount impor-tance.Currently,the production of aerospace model rocket engines does not differentiate the production and selection of motors according to the importance of the mission,which is insufficient to ensure the high reliability requirements of important launch missions.To select rocket engines with better performance quality for more critical launch missions,this paper uses fuzzy comprehensive evaluation and TOPSIS methods based on the test value or assessment informa-tion of evaluation indicators.The method scientifically and accurately ranks the performance quality of rocket engines,choosing the engines with better performance quality for more strategic missions,and providing technical support for national management decisions.
文摘A quantitative and comprehensive method of product life cycle assessment(LCA) with fuzzy theory is developed, which will help designers to select the optimum design scheme for product life cycle design(LCD). Based on the theory of multiple attribute decision making, an algorithm of comprehensive and comparative evaluation for product environmental adaptability is presented. A program is built and used in an example of design improvement. The result shows that the proposed method and algorithm are practical and effective to the development of green products.
基金Supported by Jiangsu Agricultural Science and Technology Innovation Fund(CX(12)5035)Jiangsu Agricultural "Three New Engineering" Project(SXGC[2014]299)~~
文摘[Objective] The aim was to propose a new entropy weight fuzzy compre- hensive evaluation method for assessing cotton salt tolerance, realizing the objective, accurate and comprehensive evaluation of salt tolerance of cotton. [Method] A sand culture experiment under salt stress of 150 mmol/L of NaCI was designed. The in- dicator weight was determined with the entropy weight fuzzy comprehensive evalu- ation method, based on the salt injury index of indicators. The salt tolerance of cotton was evaluated comprehensively. [Result] At the germination stage, the entropy and weight of salt injury index of germination energy, vigor index, hypocotyl length and fresh weight were highest, followed by germination rate and germination index, and of root length were lowest. At the seedling stage, the entropy and weight of salt injury index of plasma membrane permeability, root vigor and leaf expansion rate were highest, followed by plant height and net photosynthetic rate, and of shoot dry weight and root dry weight were lowest. The salt tolerance of cotton differed a- mong growth stages and cultivars. Among the 11 cultivars, CCRI-44 and CCRI-75 were steadily salt-tolerant at both germination and seedling stages; CCRI-17, Sumi- an 22, Sumian 15 and Dexiamianl had a stable moderate salt tolerance; while Sumian 12 and Simian 3 were steadily salt-sensitive. [Conclusion] The evaluated result was objective and exact, which indicated that this method could be used in comprehensive evaluation of salt tolerance of cotton.
基金Supported by National Natural Science Foundation of China(40801227)Open Foundation of Key Open Laboratory of Marine and Estuarine Fishery Resources and Ecology, Ministry of Agriculture (Open-2-04-09)~~
文摘The aquaculture pond water quality was taken as research objects,based on the general analysis of factors influencing the pond water quality,the system of index estimation and assessment standard were established after sorting by importance of the factors by means of Delphi and expert investigation.In this study,index weight was confirmed according to the importance of the factors and relative membership grade of the measured values,thus and the fuzzy comprehensive evaluation model of aquaculture pond water quality was constructed,and the fuzzy comprehensive evaluation system of freshwater aquaculture pond water quality was designed and implemented.The application of this system in the assessment of aquaculture pond water quality by a company had achieved better result.
基金Supported by the Major Project of Application Foundation and Advanced Technology of Tianjin (the Natural Science Foundation of Tianjin) (09JCZDJC19200),China~~
文摘[Objective] This study was to provide references for the evaluation of water quality in aquaculture ponds by evaluating the pond water quality using fuzzy comprehensive evaluation method based on entropy weight. [Method] The fuzzy compre- hensive evaluation method based on entropy weight was used to evaluate the water quality in the ponds with Ukraine scale carp （Cyprinus carpio） as the main cultivated fish. The average size of the fish was 71.4 g/ind, and totally three groups of pond were set with the population density of 6 000, 9 000, 12 000 ind/hm2. [Result] According to the GB3838-2002 Environmental Quality Standards for Surface Water of China, the water quality of 6 000 ind/hm2 group was Grade I, and the water quality of 9 000 and 12 000 ind/hm2 were Grade V. [Conclusion] With the increasing of feeding density, the pond water quality would worsen, however, there is no difference on water quality between 9 000 and 12 000 ind/hm2 groups.
基金Shanxi Province Science and Technology Research Project(No.20140321008-03)
文摘The paper analyzes the factors influencing machine tool selection. By using fuzzy mathematics theory, we establish a theorietical model for optimal machine tool selection considering geometric features, clamping size, machining range, machining precision and surface roughness. By means of fuzzy comprehensive evaluation method, the membership degree of machine tool selection and the largest comprehensive evaluation index are determined. Then the reasonably automatic selection of machine tool is realized in the generative computer aided process planning （CAPP） system. Finally, the finite element model based on ABAQUS is established and the cutting process of machine tool is simulated. According to the theoretical and empirical cutting parameters and the curve of surface residual stress, the optimal cutting parameters can be determined.
文摘In this paper, traffic environment quality assessment is achieved by applying fuzzy mathematics methods. Set up an assessment system, determine assessment criterion, formulate membership function, make program designs and conduct example analysis. The evaluation result is consistent with the real case. So that the method of the fuzzy evaluation is a good one for the environment quality assessment.
基金supported by the Supported by Joint Open Research Fund Program of State Key Laboratory of Hydroscience and Engineering and Tsinghua-Ningxia Yinchuan Joint Institute of Internet of Waters on Digital Water Governance(No.sklhse-2022-Iow04)Open Research Fund of State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research(No.IWHR-SKL-202217)。
文摘Climate change and economic development impact the population expansion and water shortage in the middle reaches of the Yangtze River Basin(MYRB),leading directly to drought aggravation-expansion and impacting agricultural production in the MYRB.Therefore,this study quantitatively evaluated agricultural drought vulnerability in the MYRB based on the variable fuzzy evaluation model(VFEM).The main conclusions are as follows:(1)The arable land in the MYRB gradually decreased between 2005 and 2020,whereas the forest cover decreased and then increased;(2)precipitation and evapotranspiration were the key factors affecting the agricultural drought vulnerability(e.g.,weights of 0.24 and 0.21),whereas arable land density and gross domestic product(GDP)per capita played less significant roles;and(3)the agricultural drought vulnerability in the MYRB during 2005-2020 was mainly at level 3 and below,with higher drought vulnerability in the western and northern regions,which had a higher drought risk potential.
基金supported by the Science and Technology Project of the China Southern Power Grid Co.,Ltd.(Project number:SZKJXM20230085).
文摘Flexible interconnection devices(FIDs)significantly enhance the regulation and management of complex power flows in distribution networks.Voltage source converter(VSC)-based FIDs,in particular,are pivotal for increasing system reliability and operational efficiency.These devices are crucial in supporting the extensive incorporation of electric vehicles(EVs)and renewable energy sources(RESs)into new,load-centric environments.This study evaluates four unique FID-based configurations for distribution network interconnections,revealing their distinctive features.We developed a comprehensive evaluation framework and tool by integrating the analytic hierarchy process(AHP)and fuzzy comprehensive evaluation(FCE),which includes five key performance indicators to assess these configurations.The study identifies the optimal application scenarios for each configuration and discusses their roles in enabling the seamless integration of EVs and RESs.The findings provide essential insights and guidelines for the design and implementation of adaptable,interconnected distribution networks that are equipped to meet the growing demands of future urban environments.
基金supported by the Scientific Research Project of POWERCHINA Chengdu Engineering Corporation Limited(Grant No.P50922)。
文摘The glacial lake in the Boqu Basin in Tibetan Plateau has changed significantly in recent years due to global warming,seriously affecting the natural and social environments in downstream areas.We obtained the change characteristics of glacial lakes by analyzing remote sensing images and evaluated the outburst floods susceptibility of glacial lakes in the Boqu Basin by combining fuzzy mathematics and random forest methods.An empirical formula for glacial lake hazard evaluation was established based on a fuzzy comprehensive evaluation.The confusion matrix were used to assess the evaluation effect of each method.The conclusions were as follows:(1)Under the influence of climate warming,glaciers are retreating further from the glacial lakes,and the size of glaciers that can impact these lakes is shrinking.Geological conditions,such as steep slopes around the lakes,have replaced glacier tongues as the primary factors threatening the susceptibility of the glacial lakes;(2)Among the three evaluation methods,the empirical formula offers high calculation accuracy and is the most convenient to use,which provides an accuracy rate of 85.71%in susceptibility evaluation of the Boqu Basin glacial lake and can be applied to other areas in the rapid evaluation of the susceptibility of glacial lakes;(3)The impact analysis of the collapse shows that the collapse of the Galongco fault would cause large economic losses.
基金National Natural Science Foundation of China (12202293)Sichuan Science and Technology Program (2023NSFSC0393,2022NSFSC1952)。
文摘A task allocation problem for the heterogeneous unmanned aerial vehicle (UAV) swarm in unknown environments is studied in this paper.Considering that the actual mission environment information may be unknown,the UAV swarm needs to detect the environment first and then attack the detected targets.The heterogeneity of UAVs,multiple types of tasks,and the dynamic nature of task environment lead to uneven load and time sequence problems.This paper proposes an improved contract net protocol (CNP) based task allocation scheme,which effectively balances the load of UAVs and improves the task efficiency.Firstly,two types of task models are established,including regional reconnaissance tasks and target attack tasks.Secondly,for regional reconnaissance tasks,an improved CNP algorithm using the uncertain contract is developed.Through uncertain contracts,the area size of the regional reconnaissance task is determined adaptively after this task assignment,which can improve reconnaissance efficiency and resource utilization.Thirdly,for target attack tasks,an improved CNP algorithm using the fuzzy integrated evaluation and the double-layer negotiation is presented to enhance collaborative attack efficiency through adjusting the assignment sequence adaptively and multi-layer allocation.Finally,the effectiveness and advantages of the improved method are verified through comparison simulations.
基金supported by the National Natural Science Foundation of China (No. 41071322, 71031001)
文摘For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. The coefficient of variation of each indicator is used to determine the weight instead of traditional calculating superscales method. On the other hand, fuzzy matter-elements are constructed, and normal membership degrees are used instead of traditional trapezoidal ones. The composite fuzzy matter-elements with associated coefficient are constructed through associated transformation. The levels of natural water quality are determined according to the principle of maximum correlation. The improved fuzzy matter-element evaluation method is applied to evaluate water quality of the Luokou mainstream estuary at the first ten weeks in 2011 with the coefficient of variatiola method determining the weights. Water quality of Luokou mainstream estuary is dropping from level I to level II. The results of the improved evaluation method are basically the same as the official water quality. The variation coefficient method can reduce the workload, and overcome the adverse effects from abnormal values, compared with the traditional calculating superscales method. The results of improved fuzzy matter- element evaluation method are more credible than the ones of the traditional evaluation method. The improved evaluation method can use information of monitoring data more scientifically and comprehensively, and broaden a new evaluation method for water quality assessment.
基金Under the auspices of Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX2-YW-127)National Natural Science Foundation of China (No. 40671014, 90502007)
文摘This paper explores the method of comprehensive evaluation of water resources carrying capacity and sets up an evaluation model applying the fuzzy comprehensive evaluation method. Based on the data of nature,society,economics and water resources of the Tarim River Basin in 2002,we evaluated the water resources carrying capacity of the basin by means of the model. The results show that the comprehensive grades are 0.438 and 0.454 for Aksu and Kashi prefectures respectively,where the current water resources exploitation and utilization has reached a relative high degree and there is only a very limited water carrying capacity,0.620 for Kizilsu Kirgiz Autonomous Prefecture,where water resources carrying capacity is much higher,and in between for Hotan Prefecture and Bayingolin Mongo-lian Autonomous Prefecture. As a whole,the comprehensive grade of the Tarim River Basin is 0.508 and the current water resources exploitation and utilization has reached a relative high degree. Thus,we suggest that the integrated management of the water resources in the basin should be strengthened in order to utilize water resources scientifically and sustainably.
基金Under the auspices of National Natural Science Foundation of China (No. 40830535)Knowledge Innovation Pro-gram of Chinese Academy of Sciences (No.KSCX2-YW-N-46-06)
文摘In order to improve the effectiveness of Fuzzy Synthetic Evaluation (FSE) models, a Parameter Correlation Analysis (PCA) was introduced into the FSE and a case study was carried out in the Naoli River in the Sanjiang Plain, Northeast China. The basic principle of the PCA is that the pairs of parameters which are highly correlated and linear with each other would contribute the same information to an assessment and one of them should be eliminated. The method of the PCA is that a correlation relationship among candidate parameters is examined before the FSE. If there is an apparent nonlinear or curvilinear relationship between two parameters, then both will be retained; if the correlation is significant (p<0.01), and the scatter plot suggests a linear relationship, then one of them will be deleted. However, which one will be deleted? For solving this problem, a sensitivity test was conducted and the higher sensitivity parameters remained. The results indicate that the original data should be preprocessed through the PCA for redundancy and variability. The study shows that introducing the PCA into the FSE can simplify the FSE calculation process greatly, while the results have not been changed much.
基金the National Key Research and Development Program of China(No.2017YFC1501302)the National Natural Science Foundation of China(No.41630643)the Fundamental Research Funds for the Central Universities(No.CUGCJ1701)。
文摘A slope stability evaluation method is proposed combining group decision theory,the analytic hierarchy process and fuzzy comprehensive evaluation.The index weight assignment of each evaluation element is determined by group decision theory and the analytic hierarchy process,and the membership degree of each indicator is determined based on fuzzy set theory.According to the weights and memberships,the membership degrees of the criterion layer are obtained by fuzzy operations to evaluate the slope stability.The results show that(1)the evaluation method comprehensively combines the effects of multiple factors on the slope stability,and the evaluation results are accurate;(2)the evaluation method can fully leverage the experience of the expert group and effectively avoid evaluation errors caused by the subjective bias of a single expert;(3)based on a group decision theory entropy model,this evaluation method can quantitatively evaluate the reliability of expert decisions and effectively improve the efficiency of expert group discussion;and(4)the evaluation method can transform the originally fuzzy and subjective slope stability evaluation into a quantitative evaluation.
基金Projects(40971170,51039001) supported by the National Natural Science Foundation of ChinaProject(2007AA10Z222) supported by the National High Technology Research and Development Program of China
文摘Using soil data of the Second National Field Survey,the soil fertility of wetland ecosystem of Dongting Lake was evaluated by using the technology of GIS and method of fuzzy evaluation.Integrated with the wetland actuality of Dongting Lake and particularity of paddy,seven factors (including soil organic matter,total nitrogen,total phosphorus,total potassium,available phosphorus,available potassium,and pH value),closely related with soil fertility,were chosen to establish the index system of synthetical evaluation.Based on the effect degree of each selected index on soil fertility,a judgment matrix was built,and the weight coefficient was determined by the method of correlation coefficient.Finally,under the support of the spatial analysis module of GIS (Geographic Information System),the spatial distribution properties of soil fertility in wetland ecosystem of Dongting Lake were studied.The results show that the soil fertility of Dongting Lake wetland ecosystem is not very good,and the area of type III and type IV achieves 69.8%.As a result,many countermeasures should be taken to improve the soil fertility.As for the spatial properties,the soil fertility level of central and west Dongting Lake is much higher than that of north and south part.The soil fertility of paddy field surpasses that of red soil,and the contents of soil organic matter and total nitrogen in paddy field are large.
基金support from the project of CNOOC China Limited-Shenzhen (Grant No. Z2007SLSZ-034)the foundation project of the State Key Laboratory of Petroleum Resource and Prospecting (Grant No. PRPDX2008-08) is gratefully acknowledged
文摘Drilling engineering has great uncertainty and it always involves huge investment and high risk. Risk analysis of extended reach drilling （ERD） is very important to prevent complex failures and to improve drilling efficiency. Nowadays there are few reports on how to analyze quantitatively the drilling risk for extended reach wells （ERWs）. Based on the fuzzy set theory, a comprehensive fuzzy evaluation model for analyzing risks of ERD is proposed in this paper. Well B6ERW07 is a planned 8,000-meter ERW with a high ratio of horizontal displacement （HD） to vertical depth （VD） in the Liuhua Oilfield, the South China Sea, China. On the basis of the evaluation model developed in this study, the risk for drilling Well B6ERW07 was evaluated before drilling. The evaluation result shows that the success rate of drilling this well is predicted to be 51.9%, providing important rational and scientific information for the decisionmakers.
文摘The Changjiang River (Yangtze) is one of the fastest growth areas of container transportation in China. Rail, road and water transportation have competed against each other for container transportation in the Chang-jiang River main line and its delta area. It is of significance to assess these different transportation modes scientifically in order to organize container transportation efficiently in this area and make decision for integral plan and construction of transportation system in this area. This paper outlines application of fuzzy comprehensive evaluation to appraise different modes of typical direction of containers. Twelve assessment indexes were decided. Membership functions were formulated. Evaluation results indicated that road transportation was optimal mode in the Changjiang River delta area, however water transportation was the primary way in the Changjiang River main line.
