Aiming at the problem that the traditional Dempster Shafer (D-S) evidence theory cannot deal with conflicted evidences effectively and correctly, this paper points out that the key issue of this problem is to measure ...Aiming at the problem that the traditional Dempster Shafer (D-S) evidence theory cannot deal with conflicted evidences effectively and correctly, this paper points out that the key issue of this problem is to measure the degree of conflict between evidences correctly after analyzing various improved methods. The existing evidence conflict measure methods are analyzed, and a new evidence conflict measure method called evidence similarity measure based on the Tanimoto measure is proposed, while a new evidence combination method is proposed on the basis of evidence similarity measure. Firstly, the conflict degrees between evidences are obtained through the evidence similarity measure. Then the evidence sources are modified based on the credibility of different evidences and the weights of conflicted parts of evidences on different focal elements are determined. Finally, the fusion result is obtained by this method. Numerical examples show that the proposed method can effectively fuse evidences when evidences are consistent or highly conflicted, and it has a fast convergence speed, a high degree of accuracy and good adaptability.展开更多
Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel...Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel water inrush was proposed based on improved attribute mathematical theory.The trigonometric functions were adopted to optimize the attribute mathematical theory,avoiding the influence of mutation points and linear variation zones in traditional linear measurement functions on the accuracy of the model.Based on comprehensive analysis of various factors,five parameters were selected as the evaluation indicators for the model,including tunnel head pressure,permeability coefficient of surrounding rock,crushing degree of surrounding rock,relative angle of joint plane and tunnel section size,under the principle of dimension rationality,independence,directness and quantification.The indicator classifications were determined.The links among measured data were analyzed in detail,and the objective weight of each indicator was determined by using similar weight method.Thereby the tunnel water inrush risk assessment model is established and applied in four target segments of two different tunnels in engineering.The evaluation results and the actual excavation data agree well,which indicates that the model is of high credibility and feasibility.展开更多
This paper presents an innovative approach for the fault isolation of Light Rail Vehicle (LRV) suspension system based on the Dempster-Shafer (D-S) evidence theory and its improvement application case. The considered ...This paper presents an innovative approach for the fault isolation of Light Rail Vehicle (LRV) suspension system based on the Dempster-Shafer (D-S) evidence theory and its improvement application case. The considered LRV has three rolling stocks and each one equips three sensors for monitoring the suspension system. A Kalman filter is applied to generate the residuals for fault diagnosis. For the purpose of fault isolation, a fault feature database is built in advance. The Eros and the norm distance between the fault feature of the new occurred fault and the one in the feature database are applied to measure the similarity of the feature which is the basis for the basic belief assignment to the fault, respectively. After the basic belief assignments are obtained, they are fused by using the D-S evidence theory. The fusion of the basic belief assignments increases the isolation accuracy significantly. The efficiency of the proposed method is demonstrated by two case studies.展开更多
The diversity and complexity of the parameters involved in the modeling of proton exchange membrane fuel cells(PEMFCs)have restricted further research and applications of such cells,and the similarity theory is a prom...The diversity and complexity of the parameters involved in the modeling of proton exchange membrane fuel cells(PEMFCs)have restricted further research and applications of such cells,and the similarity theory is a promising solution to this problem.The similarity theory is an effective tool to obtain compact and generalized results with the same precision as that of the basic mathematical model.This paper presents a comprehensive review of the application of the similarity theory to most aspects of PEMFCs.The advantages of using the similarity theory,such as generality,reduction in the test effort,convenient comparisons and guidance to scale up the experiment,are discussed and analyzed.Although a number of similarity criteria have been proposed in recent years,the similarity theory is not as widely applied or well accepted in PEMFC research as in the heat transfer and fluid flow domain.The objective of this paper is to demonstrate the feasibility of performing a similarity analysis for such complex systems and encourage researchers to present a dimensionless expression of their results in the follow-up PEMFC research.A key challenge is to use the similarity analysis for a complete gas-water-electricity-heat-mechanics coupled with PEMFC system and obtain the correlation between the dimensionless output voltage/current and input similarity criteria.This review indicates that none of the existing models can achieve this objective,and further research pertaining to this aspect must be performed.Several recommendations to achieve this aim,including a hierarchical classification of the criteria,are provided.展开更多
基金supported by the National Natural Science Foundation of China(61573283)
文摘Aiming at the problem that the traditional Dempster Shafer (D-S) evidence theory cannot deal with conflicted evidences effectively and correctly, this paper points out that the key issue of this problem is to measure the degree of conflict between evidences correctly after analyzing various improved methods. The existing evidence conflict measure methods are analyzed, and a new evidence conflict measure method called evidence similarity measure based on the Tanimoto measure is proposed, while a new evidence combination method is proposed on the basis of evidence similarity measure. Firstly, the conflict degrees between evidences are obtained through the evidence similarity measure. Then the evidence sources are modified based on the credibility of different evidences and the weights of conflicted parts of evidences on different focal elements are determined. Finally, the fusion result is obtained by this method. Numerical examples show that the proposed method can effectively fuse evidences when evidences are consistent or highly conflicted, and it has a fast convergence speed, a high degree of accuracy and good adaptability.
基金Project(2013CB036004) supported by National Basic Research Program(973)of ChinaProject(51378510) supported by National Natural Science Foundation of China
文摘Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel water inrush was proposed based on improved attribute mathematical theory.The trigonometric functions were adopted to optimize the attribute mathematical theory,avoiding the influence of mutation points and linear variation zones in traditional linear measurement functions on the accuracy of the model.Based on comprehensive analysis of various factors,five parameters were selected as the evaluation indicators for the model,including tunnel head pressure,permeability coefficient of surrounding rock,crushing degree of surrounding rock,relative angle of joint plane and tunnel section size,under the principle of dimension rationality,independence,directness and quantification.The indicator classifications were determined.The links among measured data were analyzed in detail,and the objective weight of each indicator was determined by using similar weight method.Thereby the tunnel water inrush risk assessment model is established and applied in four target segments of two different tunnels in engineering.The evaluation results and the actual excavation data agree well,which indicates that the model is of high credibility and feasibility.
文摘This paper presents an innovative approach for the fault isolation of Light Rail Vehicle (LRV) suspension system based on the Dempster-Shafer (D-S) evidence theory and its improvement application case. The considered LRV has three rolling stocks and each one equips three sensors for monitoring the suspension system. A Kalman filter is applied to generate the residuals for fault diagnosis. For the purpose of fault isolation, a fault feature database is built in advance. The Eros and the norm distance between the fault feature of the new occurred fault and the one in the feature database are applied to measure the similarity of the feature which is the basis for the basic belief assignment to the fault, respectively. After the basic belief assignments are obtained, they are fused by using the D-S evidence theory. The fusion of the basic belief assignments increases the isolation accuracy significantly. The efficiency of the proposed method is demonstrated by two case studies.
基金the key project of National Natural Science Foundation of China(NNSFC)[Grant No.number 51836005]the National Key Research and Development Program[Grant num-ber 2017YFB0102702]+3 种基金the Foundation for Innovative Research Groups of the National Natural Science Foundation of China[Grant number 51721004]the Basic Research Project of Shaanxi Province[Grant num-ber 2019ZDXM3-01]the 111 Project[Grant number B16038]and the Key Science and Technology Project in Henan Province(Innovation Leading Project)[Grant number 191110210200].
文摘The diversity and complexity of the parameters involved in the modeling of proton exchange membrane fuel cells(PEMFCs)have restricted further research and applications of such cells,and the similarity theory is a promising solution to this problem.The similarity theory is an effective tool to obtain compact and generalized results with the same precision as that of the basic mathematical model.This paper presents a comprehensive review of the application of the similarity theory to most aspects of PEMFCs.The advantages of using the similarity theory,such as generality,reduction in the test effort,convenient comparisons and guidance to scale up the experiment,are discussed and analyzed.Although a number of similarity criteria have been proposed in recent years,the similarity theory is not as widely applied or well accepted in PEMFC research as in the heat transfer and fluid flow domain.The objective of this paper is to demonstrate the feasibility of performing a similarity analysis for such complex systems and encourage researchers to present a dimensionless expression of their results in the follow-up PEMFC research.A key challenge is to use the similarity analysis for a complete gas-water-electricity-heat-mechanics coupled with PEMFC system and obtain the correlation between the dimensionless output voltage/current and input similarity criteria.This review indicates that none of the existing models can achieve this objective,and further research pertaining to this aspect must be performed.Several recommendations to achieve this aim,including a hierarchical classification of the criteria,are provided.
