Let be a fuzzy stochastic process and be a real valued finite variation process. We define the Lebesgue-Stieltjes integral denoted by for each by using the selection method, which is direct, nature and different from ...Let be a fuzzy stochastic process and be a real valued finite variation process. We define the Lebesgue-Stieltjes integral denoted by for each by using the selection method, which is direct, nature and different from the indirect definition appearing in some references. We shall show that this kind of integral is also measurable, continuous in time t and bounded a.s. under the Hausdorff metric.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 order to improve the influence of the uncertain and dynamic of node enterprise behavior on the performance of supply chain,the method based on stochastic process algebra for description,analysis,validation and eval...In order to improve the influence of the uncertain and dynamic of node enterprise behavior on the performance of supply chain,the method based on stochastic process algebra for description,analysis,validation and evaluation of supply chain business process model is proposed.Firstly,the description of the uncertainty of node enterprise behavior is given using the extended Unified Modeling Language sequence diagram,and mapping rule is defined from the extended Unified Modeling Language sequence diagram to stochastic process algebra.Secondly,on the basis of the acquired stochastic process algebra model,the supply chain business process model is verified with Mobility Workbench.Finally,according to the operational semantics of stochastic process algebra,the continuous-time Markov chain,isomorphic with stochastic process algebra model,is built; and the system performance evaluation of transient status and stable status is respectively conducted in accordance with Markov transfer relations and the current state of system,obtaining the predicted performance value and average performance index value for a specific period of time.The simulation experiments show that the proposed method can accurately describe the stochastic behaviors of supply chain system and interactions among nodes,effectively verify the validity of the model,and objectively and exactly evaluate design of the supply chain.展开更多
Renewable energy sources,including wind,solar,and biofuels,are essential for promoting sustainable economic development and mitigating environmental challenges.As China’s overseas investments in renewable energy expa...Renewable energy sources,including wind,solar,and biofuels,are essential for promoting sustainable economic development and mitigating environmental challenges.As China’s overseas investments in renewable energy expand,effective risk assessment and management have become critical.This study develops a comprehensive risk evaluation framework for China’s overseas renewable energy investments using the Fuzzy Analytic Hierarchy Process(FAHP).The framework incorporates political,economic,and project-specific risks,organized through three primary criteria,nine sub-criteria,and thirty tertiary indicators.By integrating expert judgments with fuzzy set theory,the FAHP methodology assigns accurate weights to risk factors and ensures consistency in evaluation.The findings identify political risks as the most significant,emphasizing their influence on investment strategies.These insights offer valuable guidance for policymakers and investors to enhance risk management strategies and ensure the sustainability of China’s renewable energy initiatives abroad.展开更多
A dissertation is a research report or scientific paper written by an author to obtain a certain degree. It reflects postgraduates’ research achievements and the educational quality of an institute, even a country. T...A dissertation is a research report or scientific paper written by an author to obtain a certain degree. It reflects postgraduates’ research achievements and the educational quality of an institute, even a country. To construct an optimized quality evaluation system for postgraduate dissertation (QESPD), we summarized the influencing factors and invited 10 experienced specialists to rate and prioritize them based on fuzzy analytic hierarchy process. Four primary indicators (innovation, integrity, scientificity and normativity) and 16 sub-indicators were selected to form the evaluation system. The order of primary indicators by weight, was innovation (0.4269), scientificity (0.2807), integrity (0.1728) and normativity (0.1196). The top five sub-dimensions were theoretical originality, scientific value, data reliability, design rationality and evidence credibility. To demonstrate the effectiveness of the proposed system, a case study was performed. In the case study, it was demonstrated that the established two-index-hierarchy QESPD in this study was a more scientific and reasonable evaluation system worthy of promotion and application.展开更多
The fuzzy static and dynamic random phenomena in an abstract separable Banach space is discussed in this paper. The representation theorems for fuzzy set valued random sets, fuzzy random elements and fuzzy set value...The fuzzy static and dynamic random phenomena in an abstract separable Banach space is discussed in this paper. The representation theorems for fuzzy set valued random sets, fuzzy random elements and fuzzy set valued stochastic processes are obtained.展开更多
Casing corrosion during CO2 injection or storage results in significant economic loss and increased production risks.Therefore,in this paper,a corroded casing risk assessment model based on analytic hierarchy process ...Casing corrosion during CO2 injection or storage results in significant economic loss and increased production risks.Therefore,in this paper,a corroded casing risk assessment model based on analytic hierarchy process and fuzzy comprehensive evaluation is established to identify potential risks in time.First,the corrosion rate and residual strength characteristics are analyzed through corrosion tests and numerical simulations,respectively,to determine the risk factors that may lead to an accident.Then,an index system for corroded casing risk evaluation is established based on six important factors:temperature,CO2 partial pressure,flow velocity,corrosion radius,corrosion depth and wellhead pressure.Subsequently,the index weights are calculated via the analytic hierarchy process.Finally,the risk level of corroded casing is obtained via the fuzzy comprehensive evaluation.The corroded casing risk assessment model has been verified by a case well,which shows that the model is valuable and feasible.It provides an effective decision-making method for the risk evaluation of corroded casing in CO2 injection well,which is conductive to improve the wellbore operation efficiency.展开更多
Stamping process,which is widely used in automobile,aerospace,machine-building industries,and etc.,is a creative process needing time and experiences.The lead time is mainly spent on stamping die design and manufactur...Stamping process,which is widely used in automobile,aerospace,machine-building industries,and etc.,is a creative process needing time and experiences.The lead time is mainly spent on stamping die design and manufacturing.As the ba- sis of die design,process design is a non-linearity and creative process,which can be solved by using the fuzzy synthetic evaluation. In this paper,the potential o f fuzzy synthetic evaluation for dealing with stamping process design was explored.The influencing factor set,factor weight set,evaluation set,single factor fuzzy evaluation matrix,and fuzzy synthetic evaluation scheme were studied.Finally,the washer part,considering forming equipment,part dimensions and other factors,was selected to testify the evaluation process.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
Generally, mine roads are located in the mountain areas, as its complex topography, mostly along the river near the cliffs, steep bend anxious, the mine road design has to adopt lower technical standards relatively an...Generally, mine roads are located in the mountain areas, as its complex topography, mostly along the river near the cliffs, steep bend anxious, the mine road design has to adopt lower technical standards relatively and usually is lack of traffic safety facilities. Especially, there are mainly medium-sized vehicles on mine road, under the heavy traffic vehicles affect repeatedly, high frequency of traffic accidents more easily happen in mine road area and cause serious effects on life or property. Combining with the particularity of mine road safety environment, this paper studies the basic theory of safety evaluation, analyses the factors of traffic safety design and special mine terrain conditions, and then establishes mine road safety index system and evaluation model based on the principles such as systematicness, independent indexes, qualitative and quantitative analysis, feasibility, scientificity and reliability. At last, the paper successfully evaluates the safety of road in Huang Mailing phosphate rock area with fuzzy AHP method based on engineering project.展开更多
For some products,degradation mechanisms change during testing,and therefore,their degradation patterns vary at different points in time;these points are called change-points.Owing to the limitation of measurement cos...For some products,degradation mechanisms change during testing,and therefore,their degradation patterns vary at different points in time;these points are called change-points.Owing to the limitation of measurement costs,time intervals for degradation measurements are usually very long,and thus,the value of change-points cannot be determined.Conventionally,a certain degradation measurement is selected as the change-point in a two-phase degradation process.According to the tendency of the two-phase degradation process,the change-point is probably located in the interval between two neighboring degradation measurements,and it is a fuzzy variable.The imprecision of the change-point may lead to the incorrect product’s reliability evaluation results.In this paper,based on the fuzzy theory,a two-phase degradation model with a fuzzy change-point and a statistical analysis method are proposed.First,a two-phase Wiener degradation model is developed according to the membership function of the change-point.Second,the reliability evaluation is carried out using maximum likelihood estimation and a fuzzy simulation approach.Finally,the proposed methodology is verified via a case study.The results of the study show that the proposed methodology can achieve more believable reliability evaluation results compared with those of the conventional approach.展开更多
Drought conditions at a given location evolve randomly through time and are typically characterized by severity and duration. Researchers interested in modeling the economic effects of drought on agriculture or other ...Drought conditions at a given location evolve randomly through time and are typically characterized by severity and duration. Researchers interested in modeling the economic effects of drought on agriculture or other water users often capture the stochastic nature of drought and its conditions via multiyear, stochastic economic models. Three major sources of uncertainty in application of a multiyear discrete stochastic model to evaluate user preparedness and response to drought are: (1) the assumption of independence of yearly weather conditions, (2) linguistic vagueness in the definition of drought itself, and (3) the duration of drought. One means of addressing these uncertainties is to re-cast drought as a stochastic, multiyear process using a “fuzzy” semi-Markov process. In this paper, we review “crisp” versus “fuzzy” representations of drought and show how fuzzy semi-Markov processes can aid researchers in developing more robust multiyear, discrete stochastic models.展开更多
Bridge quality assessment is an important part in the final acceptance of new bridge construction,and it is also the main basis for the reinforcement or removal of old bridges.We evaluated the weight of each affecting...Bridge quality assessment is an important part in the final acceptance of new bridge construction,and it is also the main basis for the reinforcement or removal of old bridges.We evaluated the weight of each affecting factor to the upper events using progressive analytical hierarchy process(AHP)with the adoption of 3 scaling,reduced the calculation in analytical process,and precluded the nonuniformity of the scaling system.We obtained a comprehensive evaluation system of bridge quality, and verified its pra...展开更多
Green manufacturing is a mode to realize environmental friendliness by considering the environmental impact and energy consumption in manufacturing process.In order to make an environmental friendly assessment for man...Green manufacturing is a mode to realize environmental friendliness by considering the environmental impact and energy consumption in manufacturing process.In order to make an environmental friendly assessment for manufacturing process,a multi-criteria decision making( MCDM) model combined with fuzzy analytic hierarchy process( FAHP) and fuzzy technique for order preference by similarity to ideal solution( FTOPSIS) is proposed in this work.The environmental and resource criteria and manufacturing process objects are identified as the first step.Then,the weights of the criteria are calculated by FAHP.Finally,based on experts' evaluation using fuzzy words,the manufacturing process objects are ranked by FTOPSIS.The proposed methodology is applied to a gear shaft manufacturing.The sensitivity analysis and comparisons are implemented to prove its robustness and effectiveness for the ecofriendly assessment for process objects.展开更多
In our previous work, we study fuzzy Itôintegrals driven by a fuzzy Brownian motion. In this article, we continue this study. The purpose of this paper is to study the weak uniqueness of fuzzy stochastic diff...In our previous work, we study fuzzy Itôintegrals driven by a fuzzy Brownian motion. In this article, we continue this study. The purpose of this paper is to study the weak uniqueness of fuzzy stochastic differential equations taking into account fuzzy Brownian motion. For instance, we construct the fuzzy stochastic differential equation driven by a fuzzy Brownian motion. To define and prove our results, we use the fuzzification, the alpha cut method and the Hausdorff distance between two fuzzy quantities. Some results are to our credit in this article like the instance, we construct the fuzzy stochastic differrential equation driven by fuzzy Brownian motion. Furthermore, we develop fuzzy Itôcalculus driven by a fuzzy Brownian motion. Our result complement existing ones in that the fuzzy version of Brownian motion is taken into account.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
Historical and cultural blocks are witnesses of history and inheritors of culture. As one of the main spaces for outdoor interaction in historical and cultural blocks, the improvement of its vitality is of great signi...Historical and cultural blocks are witnesses of history and inheritors of culture. As one of the main spaces for outdoor interaction in historical and cultural blocks, the improvement of its vitality is of great significance for the improvement of residential environment and the better inheritance of history and culture. Taking Daopashi Street in Anqing City as an example, an evaluation model of landscape spatial vitality of historical and cultural blocks was constructed from three aspects of viewing function, store status and service facilities, and analytic hierarchy process was used to determine the index weight and vaguely evaluate the landscape spatial vitality of historical and cultural blocks. The results show that through the comparison of weight, architectural style(0.317), the practicability of service facilities(0.168) and plant landscape(0.165) had a significant impact on the landscape spatial vitality of historical and cultural blocks,and the landscape spatial vitality of historical and cultural blocks in Daopashi Street in Anqing City was at a good level.展开更多
Based on the modern comprehensive evaluation method, in accordance with the scientific, objective and systematic principles, we select four factors (economic, social, ecological and landscape benefits), to establish t...Based on the modern comprehensive evaluation method, in accordance with the scientific, objective and systematic principles, we select four factors (economic, social, ecological and landscape benefits), to establish the evaluation indicator system of comprehensive benefits of rural land consolidation. Then using the theory of fuzzy mathematics (FUZZY) and fuzzy relationship synthesis theory, we establish the fuzzy evaluation model of comprehensive benefits of land consolidation; using analytic hierarchy process (AHP), we determine the weight of each indicator, and conduct fuzzy comprehensive evaluation from various levels. By the weighted average synthesis algorithm, we calculate the evaluation indicators and finally summarize the overall evaluation results for comprehensive evaluation. Taking the case of land consolidation project in Shangyao Town, Datong District, Huainan City in Anhui Province, we calculate the case data based on Matlab software, and the calculation results and evaluation level are consistent with the project acceptance results, verifying the feasibility of this evaluation method.展开更多
文摘Let be a fuzzy stochastic process and be a real valued finite variation process. We define the Lebesgue-Stieltjes integral denoted by for each by using the selection method, which is direct, nature and different from the indirect definition appearing in some references. We shall show that this kind of integral is also measurable, continuous in time t and bounded a.s. under the Hausdorff metric.
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.
基金Sponsored by the National High-Tech.R&D Program for CIMS,China(Grant No.2007AA04Z146)
文摘In order to improve the influence of the uncertain and dynamic of node enterprise behavior on the performance of supply chain,the method based on stochastic process algebra for description,analysis,validation and evaluation of supply chain business process model is proposed.Firstly,the description of the uncertainty of node enterprise behavior is given using the extended Unified Modeling Language sequence diagram,and mapping rule is defined from the extended Unified Modeling Language sequence diagram to stochastic process algebra.Secondly,on the basis of the acquired stochastic process algebra model,the supply chain business process model is verified with Mobility Workbench.Finally,according to the operational semantics of stochastic process algebra,the continuous-time Markov chain,isomorphic with stochastic process algebra model,is built; and the system performance evaluation of transient status and stable status is respectively conducted in accordance with Markov transfer relations and the current state of system,obtaining the predicted performance value and average performance index value for a specific period of time.The simulation experiments show that the proposed method can accurately describe the stochastic behaviors of supply chain system and interactions among nodes,effectively verify the validity of the model,and objectively and exactly evaluate design of the supply chain.
基金supported by the project VSB-TU Ostrava,SP2024/045.
文摘Renewable energy sources,including wind,solar,and biofuels,are essential for promoting sustainable economic development and mitigating environmental challenges.As China’s overseas investments in renewable energy expand,effective risk assessment and management have become critical.This study develops a comprehensive risk evaluation framework for China’s overseas renewable energy investments using the Fuzzy Analytic Hierarchy Process(FAHP).The framework incorporates political,economic,and project-specific risks,organized through three primary criteria,nine sub-criteria,and thirty tertiary indicators.By integrating expert judgments with fuzzy set theory,the FAHP methodology assigns accurate weights to risk factors and ensures consistency in evaluation.The findings identify political risks as the most significant,emphasizing their influence on investment strategies.These insights offer valuable guidance for policymakers and investors to enhance risk management strategies and ensure the sustainability of China’s renewable energy initiatives abroad.
文摘A dissertation is a research report or scientific paper written by an author to obtain a certain degree. It reflects postgraduates’ research achievements and the educational quality of an institute, even a country. To construct an optimized quality evaluation system for postgraduate dissertation (QESPD), we summarized the influencing factors and invited 10 experienced specialists to rate and prioritize them based on fuzzy analytic hierarchy process. Four primary indicators (innovation, integrity, scientificity and normativity) and 16 sub-indicators were selected to form the evaluation system. The order of primary indicators by weight, was innovation (0.4269), scientificity (0.2807), integrity (0.1728) and normativity (0.1196). The top five sub-dimensions were theoretical originality, scientific value, data reliability, design rationality and evidence credibility. To demonstrate the effectiveness of the proposed system, a case study was performed. In the case study, it was demonstrated that the established two-index-hierarchy QESPD in this study was a more scientific and reasonable evaluation system worthy of promotion and application.
文摘The fuzzy static and dynamic random phenomena in an abstract separable Banach space is discussed in this paper. The representation theorems for fuzzy set valued random sets, fuzzy random elements and fuzzy set valued stochastic processes are obtained.
基金This work was supported by the National Natural Science Foundation of China(Grant No.2016ZX05042004)the Joint Funds of the National Natural Science Foundation of China(Grant no.U1762104)+3 种基金the Major Scientific and Technological Projects of CNPC(Grant No.ZD2019-184-004)the Fundamental Research Funds for the Central Universities(20CX02306A)the Opening Fund of National Engineering Laboratory of Offshore Geophysical and Exploration EquipmentThe authors also would like to express their sincere gratitude to Dr.Zhang Dalei for his assistance in corrosion tests.
文摘Casing corrosion during CO2 injection or storage results in significant economic loss and increased production risks.Therefore,in this paper,a corroded casing risk assessment model based on analytic hierarchy process and fuzzy comprehensive evaluation is established to identify potential risks in time.First,the corrosion rate and residual strength characteristics are analyzed through corrosion tests and numerical simulations,respectively,to determine the risk factors that may lead to an accident.Then,an index system for corroded casing risk evaluation is established based on six important factors:temperature,CO2 partial pressure,flow velocity,corrosion radius,corrosion depth and wellhead pressure.Subsequently,the index weights are calculated via the analytic hierarchy process.Finally,the risk level of corroded casing is obtained via the fuzzy comprehensive evaluation.The corroded casing risk assessment model has been verified by a case well,which shows that the model is valuable and feasible.It provides an effective decision-making method for the risk evaluation of corroded casing in CO2 injection well,which is conductive to improve the wellbore operation efficiency.
文摘Stamping process,which is widely used in automobile,aerospace,machine-building industries,and etc.,is a creative process needing time and experiences.The lead time is mainly spent on stamping die design and manufacturing.As the ba- sis of die design,process design is a non-linearity and creative process,which can be solved by using the fuzzy synthetic evaluation. In this paper,the potential o f fuzzy synthetic evaluation for dealing with stamping process design was explored.The influencing factor set,factor weight set,evaluation set,single factor fuzzy evaluation matrix,and fuzzy synthetic evaluation scheme were studied.Finally,the washer part,considering forming equipment,part dimensions and other factors,was selected to testify the evaluation process.
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.
文摘Generally, mine roads are located in the mountain areas, as its complex topography, mostly along the river near the cliffs, steep bend anxious, the mine road design has to adopt lower technical standards relatively and usually is lack of traffic safety facilities. Especially, there are mainly medium-sized vehicles on mine road, under the heavy traffic vehicles affect repeatedly, high frequency of traffic accidents more easily happen in mine road area and cause serious effects on life or property. Combining with the particularity of mine road safety environment, this paper studies the basic theory of safety evaluation, analyses the factors of traffic safety design and special mine terrain conditions, and then establishes mine road safety index system and evaluation model based on the principles such as systematicness, independent indexes, qualitative and quantitative analysis, feasibility, scientificity and reliability. At last, the paper successfully evaluates the safety of road in Huang Mailing phosphate rock area with fuzzy AHP method based on engineering project.
基金the National Natural Science Foundation of China(No.61703391)。
文摘For some products,degradation mechanisms change during testing,and therefore,their degradation patterns vary at different points in time;these points are called change-points.Owing to the limitation of measurement costs,time intervals for degradation measurements are usually very long,and thus,the value of change-points cannot be determined.Conventionally,a certain degradation measurement is selected as the change-point in a two-phase degradation process.According to the tendency of the two-phase degradation process,the change-point is probably located in the interval between two neighboring degradation measurements,and it is a fuzzy variable.The imprecision of the change-point may lead to the incorrect product’s reliability evaluation results.In this paper,based on the fuzzy theory,a two-phase degradation model with a fuzzy change-point and a statistical analysis method are proposed.First,a two-phase Wiener degradation model is developed according to the membership function of the change-point.Second,the reliability evaluation is carried out using maximum likelihood estimation and a fuzzy simulation approach.Finally,the proposed methodology is verified via a case study.The results of the study show that the proposed methodology can achieve more believable reliability evaluation results compared with those of the conventional approach.
文摘Drought conditions at a given location evolve randomly through time and are typically characterized by severity and duration. Researchers interested in modeling the economic effects of drought on agriculture or other water users often capture the stochastic nature of drought and its conditions via multiyear, stochastic economic models. Three major sources of uncertainty in application of a multiyear discrete stochastic model to evaluate user preparedness and response to drought are: (1) the assumption of independence of yearly weather conditions, (2) linguistic vagueness in the definition of drought itself, and (3) the duration of drought. One means of addressing these uncertainties is to re-cast drought as a stochastic, multiyear process using a “fuzzy” semi-Markov process. In this paper, we review “crisp” versus “fuzzy” representations of drought and show how fuzzy semi-Markov processes can aid researchers in developing more robust multiyear, discrete stochastic models.
基金Funded by the Development Foundation of Key Laboratory in Bridge-structure Engineering Ministry of Communication,P.R.China(No.CQSLBF-Y07-3)
文摘Bridge quality assessment is an important part in the final acceptance of new bridge construction,and it is also the main basis for the reinforcement or removal of old bridges.We evaluated the weight of each affecting factor to the upper events using progressive analytical hierarchy process(AHP)with the adoption of 3 scaling,reduced the calculation in analytical process,and precluded the nonuniformity of the scaling system.We obtained a comprehensive evaluation system of bridge quality, and verified its pra...
基金National Natural Science Foundation of China(No.51475459)the Priority Academic Program Development of Jiangsu Higher Education Institutions of China(No.PAPD)
文摘Green manufacturing is a mode to realize environmental friendliness by considering the environmental impact and energy consumption in manufacturing process.In order to make an environmental friendly assessment for manufacturing process,a multi-criteria decision making( MCDM) model combined with fuzzy analytic hierarchy process( FAHP) and fuzzy technique for order preference by similarity to ideal solution( FTOPSIS) is proposed in this work.The environmental and resource criteria and manufacturing process objects are identified as the first step.Then,the weights of the criteria are calculated by FAHP.Finally,based on experts' evaluation using fuzzy words,the manufacturing process objects are ranked by FTOPSIS.The proposed methodology is applied to a gear shaft manufacturing.The sensitivity analysis and comparisons are implemented to prove its robustness and effectiveness for the ecofriendly assessment for process objects.
文摘In our previous work, we study fuzzy Itôintegrals driven by a fuzzy Brownian motion. In this article, we continue this study. The purpose of this paper is to study the weak uniqueness of fuzzy stochastic differential equations taking into account fuzzy Brownian motion. For instance, we construct the fuzzy stochastic differential equation driven by a fuzzy Brownian motion. To define and prove our results, we use the fuzzification, the alpha cut method and the Hausdorff distance between two fuzzy quantities. Some results are to our credit in this article like the instance, we construct the fuzzy stochastic differrential equation driven by fuzzy Brownian motion. Furthermore, we develop fuzzy Itôcalculus driven by a fuzzy Brownian motion. Our result complement existing ones in that the fuzzy version of Brownian motion is taken into account.
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the Research on the Application of the Perception Teaching of“Graphics”in Architectural Design Course(JZ213702)Landscape Architecture Stracture(JZ213704)+1 种基金Research on the Teaching of Architectural Design Course for Urban and Rural Planning Major with the concept of“Local Design”(JZ223706)Anhui Provincial Key Laboratory of Huizhou Architecture Open Subjects Funding Project(HPJZ-2020-03).
文摘Historical and cultural blocks are witnesses of history and inheritors of culture. As one of the main spaces for outdoor interaction in historical and cultural blocks, the improvement of its vitality is of great significance for the improvement of residential environment and the better inheritance of history and culture. Taking Daopashi Street in Anqing City as an example, an evaluation model of landscape spatial vitality of historical and cultural blocks was constructed from three aspects of viewing function, store status and service facilities, and analytic hierarchy process was used to determine the index weight and vaguely evaluate the landscape spatial vitality of historical and cultural blocks. The results show that through the comparison of weight, architectural style(0.317), the practicability of service facilities(0.168) and plant landscape(0.165) had a significant impact on the landscape spatial vitality of historical and cultural blocks,and the landscape spatial vitality of historical and cultural blocks in Daopashi Street in Anqing City was at a good level.
基金Supported by Open Research Foundation Project of Digital National Land Key Laboratory of Jiangxi Province (Grant No.:DLLJ201211)Scientific and Technological Project of Anhui Province National Land Resources (Grant No.:2011-K-11)
文摘Based on the modern comprehensive evaluation method, in accordance with the scientific, objective and systematic principles, we select four factors (economic, social, ecological and landscape benefits), to establish the evaluation indicator system of comprehensive benefits of rural land consolidation. Then using the theory of fuzzy mathematics (FUZZY) and fuzzy relationship synthesis theory, we establish the fuzzy evaluation model of comprehensive benefits of land consolidation; using analytic hierarchy process (AHP), we determine the weight of each indicator, and conduct fuzzy comprehensive evaluation from various levels. By the weighted average synthesis algorithm, we calculate the evaluation indicators and finally summarize the overall evaluation results for comprehensive evaluation. Taking the case of land consolidation project in Shangyao Town, Datong District, Huainan City in Anhui Province, we calculate the case data based on Matlab software, and the calculation results and evaluation level are consistent with the project acceptance results, verifying the feasibility of this evaluation method.
