Purpose-This study aims to ensure the operation safety of high speed trains,it is necessary to carry out nondestructive monitoring of the tensile damage of the gearbox housing material in rail time,yet the traditional...Purpose-This study aims to ensure the operation safety of high speed trains,it is necessary to carry out nondestructive monitoring of the tensile damage of the gearbox housing material in rail time,yet the traditional tests of mechanical property can hardly meet this requirement.Design/methodology/approach-In this study the acoustic emission(AE)technology is applied in the tensile tests of the gearbox housing material of an high-speed rail(HSR)train,during which the acoustic signatures are acquired for parameter analysis.Afterward,the support vector machine(SVM)classifier is introduced to identify and classify the characteristic parameters extracted,on which basis the SVM is improved and the weighted support vector machine(WSVM)method is applied to effectively reduce the misidentification of the SVM classifier.Through the study of the law of relations between the characteristic values and the tensile life,a degradation model of the gearbox housing material amid tensile is built.Findings-The results show that the growth rate of the logarithmic hit count of AE signals and that of logarithmic amplitude can well characterize the stage of the material tensile process,and the WSVM method can improve the classification accuracy of the imbalanced data to above 94%.The degradation model built can identify the damage occurred to the HSR gearbox housing material amid the tensile process and predict the service life remains.Originality/value-The results of this study provide new concepts for the life prediction of tensile samples,and more further tests should be conducted to verify the conclusion of this research.展开更多
The evaluation model was established to estimate the number of houses collapsed during typhoon disaster for Zhejiang Province.The factor leading to disaster,the environment fostering disaster and the exposure of build...The evaluation model was established to estimate the number of houses collapsed during typhoon disaster for Zhejiang Province.The factor leading to disaster,the environment fostering disaster and the exposure of buildings were processed by Principal Component Analysis.The key factor was extracted to support input of vector machine model and to build an evaluation model;the historical fitting result kept in line with the fact.In the real evaluation of two typhoons landed in Zhejiang Province in 2008 and 2009,the coincidence of evaluating result and actual value proved the feasibility of this model.展开更多
As a consequence of developing technology, various medical developments and environmental factors, the population of elderly people has been rising. Future predictions show a rising trend for designing for the elderly...As a consequence of developing technology, various medical developments and environmental factors, the population of elderly people has been rising. Future predictions show a rising trend for designing for the elderly and. In order for seniors to be able to appear in community life, to be self-sufficient and live their lives independently, supportive environments are required. Being able to sustain seniors＇ lives has to be seen as a civic right and architectural design should be considered as a tool to get these rights. As linked to everyday living, homes should be a starting point to get these rights. Being in the core of everyday activities, the spaces in dwellings should meet life-span design criteria. Fundamental principles lying under the aspects of design, dimensions, details, colors and symbols of supportive environments should not be affected from generation gap and senium and should rather aim at this user group. These fundamentals can briefly be listed as, change as less as possible, design for self-sufficiency, communication and socialization. In the paper, the focus is on these fundamental design principles for residential spaces, together with the research of reflections of factors, affecting health, security and mobility deriving from mobility disabilities, perception and memory weakening, specifically to bathroom design.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.U61273205).
文摘Purpose-This study aims to ensure the operation safety of high speed trains,it is necessary to carry out nondestructive monitoring of the tensile damage of the gearbox housing material in rail time,yet the traditional tests of mechanical property can hardly meet this requirement.Design/methodology/approach-In this study the acoustic emission(AE)technology is applied in the tensile tests of the gearbox housing material of an high-speed rail(HSR)train,during which the acoustic signatures are acquired for parameter analysis.Afterward,the support vector machine(SVM)classifier is introduced to identify and classify the characteristic parameters extracted,on which basis the SVM is improved and the weighted support vector machine(WSVM)method is applied to effectively reduce the misidentification of the SVM classifier.Through the study of the law of relations between the characteristic values and the tensile life,a degradation model of the gearbox housing material amid tensile is built.Findings-The results show that the growth rate of the logarithmic hit count of AE signals and that of logarithmic amplitude can well characterize the stage of the material tensile process,and the WSVM method can improve the classification accuracy of the imbalanced data to above 94%.The degradation model built can identify the damage occurred to the HSR gearbox housing material amid the tensile process and predict the service life remains.Originality/value-The results of this study provide new concepts for the life prediction of tensile samples,and more further tests should be conducted to verify the conclusion of this research.
基金Supported by Scientific Research Project for Commonwealth (GYHY200806017)Innovation Project for Graduate of Jiangsu Province (CX09S-018Z)
文摘The evaluation model was established to estimate the number of houses collapsed during typhoon disaster for Zhejiang Province.The factor leading to disaster,the environment fostering disaster and the exposure of buildings were processed by Principal Component Analysis.The key factor was extracted to support input of vector machine model and to build an evaluation model;the historical fitting result kept in line with the fact.In the real evaluation of two typhoons landed in Zhejiang Province in 2008 and 2009,the coincidence of evaluating result and actual value proved the feasibility of this model.
文摘As a consequence of developing technology, various medical developments and environmental factors, the population of elderly people has been rising. Future predictions show a rising trend for designing for the elderly and. In order for seniors to be able to appear in community life, to be self-sufficient and live their lives independently, supportive environments are required. Being able to sustain seniors＇ lives has to be seen as a civic right and architectural design should be considered as a tool to get these rights. As linked to everyday living, homes should be a starting point to get these rights. Being in the core of everyday activities, the spaces in dwellings should meet life-span design criteria. Fundamental principles lying under the aspects of design, dimensions, details, colors and symbols of supportive environments should not be affected from generation gap and senium and should rather aim at this user group. These fundamentals can briefly be listed as, change as less as possible, design for self-sufficiency, communication and socialization. In the paper, the focus is on these fundamental design principles for residential spaces, together with the research of reflections of factors, affecting health, security and mobility deriving from mobility disabilities, perception and memory weakening, specifically to bathroom design.
