The theory of economic life prediction and reliability assessment of aircraft structures has a significant effect on safety of air-craft structures.It is based on the two-stage theory of fatigue process and can guaran...The theory of economic life prediction and reliability assessment of aircraft structures has a significant effect on safety of air-craft structures.It is based on the two-stage theory of fatigue process and can guarantee the safety and reliability of structures.According to the fatigue damage process,the fatigue scatter factors of crack initiation stage and crack propagation stage are given respectively.At the same time,mathematical models of fatigue life prediction are presented by utilizing the fatigue scatter factors and full scale test results of aircraft structures.Furthermore,the economic life model is put forward.The model is of sig-nificant scientific value for products to provide longer economic life,higher reliability and lower cost.The theory of economic life prediction and reliability assessment of aircraft structures has been successfully applied to determining and extending the structural life for thousands of airplanes.展开更多
目的评价中文版可重复神经心理状态测验（repeatable battery for the assessment of neuro-psychological status，RBANS）在精神分裂症患者人群应用的信度和效度。方法筛查100名精神分裂症患者，其中98名患者完成中文版RBANS问卷、世...目的评价中文版可重复神经心理状态测验（repeatable battery for the assessment of neuro-psychological status，RBANS）在精神分裂症患者人群应用的信度和效度。方法筛查100名精神分裂症患者，其中98名患者完成中文版RBANS问卷、世界卫生组织认知功能评价成套神经心理测验（WHO-BCAI）和Stroop字色干扰测验，同时使用阳性阴性综合征量表（PANSS）和临床疗效总评（CGI）评价患者病情的严重程度。其中43例患者间隔一月后复测RBANS。对获取的数据进行相关分析等。结果RBANS总分与RBANS5个因子分的相关系数具有统计学意义（r=0.475-0.778，P〈0.001）。RBANS总分重测信度ICC为0.877，5个因子ICC从0.453-0.875。除了RBANS的视觉空间结构与WHO—BCAI的延迟回忆，RBANS的语言与WHO—BCAI的视觉辨认功能、空间结构相关系数未达到统计学意义外，RBANS总分、各因子分与WHO-BCAI及Stroop字色干扰测验的相关系数具有统计学意义。结论中文版RBANS在精神分裂症患者中应用具有较好的信度和效度，可作为精神分裂症患者认知功能水平的筛查工具。展开更多
As few or no failures occur during accelerated life test,it is difficult to assess reliability for long-life products with traditional life tests.Reliability assessment using degradation data of product performance ov...As few or no failures occur during accelerated life test,it is difficult to assess reliability for long-life products with traditional life tests.Reliability assessment using degradation data of product performance over time becomes a significant approach.Aerospace electrical connector is researched in this paper.Through the analysis of failure mechanism,the performance degradation law is obtained and the statistical model for degradation failure is set up; according to the research on statistical analysis methods for degradation data,accelerated life test theory and method for aerospace electrical connector based on performance degradation is proposed by improving time series analysis method,and the storage reliability is assessed for Y11X series of aerospace electrical connector with degradation data from accelerated degradation test.The result obtained is basically consistent with that obtained from accelerated life test based on failure data,and the two estimates of product＇s characteristic life only have a difference of 8.7%,but the test time shortens about a half.As a result,a systemic approach is proposed for reliability assessment of highly reliable and long-life aerospace product.展开更多
基金National Natural Science Foundation of China (50135010)
文摘The theory of economic life prediction and reliability assessment of aircraft structures has a significant effect on safety of air-craft structures.It is based on the two-stage theory of fatigue process and can guarantee the safety and reliability of structures.According to the fatigue damage process,the fatigue scatter factors of crack initiation stage and crack propagation stage are given respectively.At the same time,mathematical models of fatigue life prediction are presented by utilizing the fatigue scatter factors and full scale test results of aircraft structures.Furthermore,the economic life model is put forward.The model is of sig-nificant scientific value for products to provide longer economic life,higher reliability and lower cost.The theory of economic life prediction and reliability assessment of aircraft structures has been successfully applied to determining and extending the structural life for thousands of airplanes.
文摘目的评价中文版可重复神经心理状态测验（repeatable battery for the assessment of neuro-psychological status，RBANS）在精神分裂症患者人群应用的信度和效度。方法筛查100名精神分裂症患者，其中98名患者完成中文版RBANS问卷、世界卫生组织认知功能评价成套神经心理测验（WHO-BCAI）和Stroop字色干扰测验，同时使用阳性阴性综合征量表（PANSS）和临床疗效总评（CGI）评价患者病情的严重程度。其中43例患者间隔一月后复测RBANS。对获取的数据进行相关分析等。结果RBANS总分与RBANS5个因子分的相关系数具有统计学意义（r=0.475-0.778，P〈0.001）。RBANS总分重测信度ICC为0.877，5个因子ICC从0.453-0.875。除了RBANS的视觉空间结构与WHO—BCAI的延迟回忆，RBANS的语言与WHO—BCAI的视觉辨认功能、空间结构相关系数未达到统计学意义外，RBANS总分、各因子分与WHO-BCAI及Stroop字色干扰测验的相关系数具有统计学意义。结论中文版RBANS在精神分裂症患者中应用具有较好的信度和效度，可作为精神分裂症患者认知功能水平的筛查工具。
基金supported by National Natural Science Foundation of China (Grant No. 50935002,Grant No. 51075370,Grant No. 51105341)National Hi-tech Research and Development Program of China (863 Program,Grant No. 2007AA04Z409)Civil Aerospace Science and Technology Pre-research Project of China (Grant No. B122006 2302)
文摘As few or no failures occur during accelerated life test,it is difficult to assess reliability for long-life products with traditional life tests.Reliability assessment using degradation data of product performance over time becomes a significant approach.Aerospace electrical connector is researched in this paper.Through the analysis of failure mechanism,the performance degradation law is obtained and the statistical model for degradation failure is set up; according to the research on statistical analysis methods for degradation data,accelerated life test theory and method for aerospace electrical connector based on performance degradation is proposed by improving time series analysis method,and the storage reliability is assessed for Y11X series of aerospace electrical connector with degradation data from accelerated degradation test.The result obtained is basically consistent with that obtained from accelerated life test based on failure data,and the two estimates of product＇s characteristic life only have a difference of 8.7%,but the test time shortens about a half.As a result,a systemic approach is proposed for reliability assessment of highly reliable and long-life aerospace product.
