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Compressive behavior of composite panels with deeply embedded delamination

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航空动力学报 2012年第1期27卷 82-88页

作者： fu hui-min PENG Bo Research Center of Small Sample Technology Beijing University of Aeronautics and AstronauticsBeijing 100191China

The compressive behavior of laminates with a deeply embedded circular delamination was studied numerically and *** the finite element analysis(FEA),virtual crack closure technique(VCCT) and B-K law were employed to simulate the delamination growth,and the contact of the two substrates was *** effect of the delamination size and through-thickness position on the compressive behavior of laminates with an artificially embedded circular delamination was *** is found that the through-thickness position affects the buckling mode,which then strongly influences delamination growth speed and direction,as well as the dominant component energy release rate(ERR).The numerical results agreed well with the experimental results.

关键词： composite compressive failure delamination propagation buckling VCCT(virtual crack uosure technique)

Heteroscedastic regression analysis method for mixed data

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航空动力学报 2011年第4期26卷 721-726页

作者： fu hui-min YUE Xiao-rui Research Center of Small Sample Technology Beijing University of Aeronautics and Astronautics Beijing 100191 China

The heteroscedastic regression model was established and the heteroscedastic regression analysis method was presented for mixed data composed of complete data,type-Ⅰ censored data and type-Ⅱ censored data from the location-scale *** best unbiased estimations of regression coefficients,as well as the confidence limits of the location parameter and scale parameter were ***,the point estimations and confidence limits of percentiles were ***,the traditional multiple regression analysis method which is only suitable to the complete data from normal distribution can be extended to the cases of heteroscedastic mixed data and the location-scale *** the presented method has a broad range of promising applications.

关键词： heteroscedastic regression analysis censored data performance test life prediction reliability analysis

Improved uncertainty propagation method of dynamic model for Mars entry spacecraft

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航空动力学报 2014年第5期29卷 1223-1233页

作者： fu hui-min XIAO Qiang WU Yun-zhang Research Center of Small Sample Technology Beijing University of Aeronautics and Astronautics

In order to research the uncertainty propagation laws of Mars entry dynamic equations for the Mars entry phase,an improved method was presented for analyzing the effect of the initial state uncertainties and uncertainty factor on the system state in the state *** applying the method to the entry phase of one of the NASA Mars exploration missions,the simulation results agreed well with the Monte Carlo method,especially the flight path angle simulation at least reaching 92%.It is found that the improved method can not only predict the uncertainty propagation laws with high accuracy of at least 92%in flight path angle simulation and large application scope from-0.1degree to 0.1degree,compared with local linearization method,but also save several hours relative to Monte Carlo method.

关键词：不确定性传播规律动态方程月出入高精度的改进方法

Compressive properties of homemade carbon fiber composite laminates with delamination defect

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航空动力学报 2013年第1期28卷 10-15页

作者： fu hui-min YANG Yu-song ZHANG Yong-bo Research Center of Small Sample Technology Beijing University of Aeronautics and Astronautics

Large numbers of aircraft composite structures were researched,and the distribution of delamination sizes and though thickness positions in the composite laminates were *** experiment was conducted to probe into the effect of delamination sizes and through thickness positions on the compressive strengths of laminates with single embedded circular delamination with the most dangerous delamination sizes and positions defined from the distribution.A shell model was established for compressive strength prediction,and the virtual crack closure technique(VCCT) was employed for the strain energy release rate *** finite element(FE) prediction was in good agreement with the experimental measurements,for the predicted compressive strengths stood within 10%error of experimental *** was observed that the compressive strength was highly effected by the delamination size,while the though thickness position of delamination did not have significant effect on the compressive strength.

关键词： homemade carbon fiber composite compressive strength virtual crack closure technique element simulation

Progressive prediction method for failure data with small sample size

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航空动力学报 2011年第9期26卷 2049-2053页

作者： WANG Zhi-hua fu hui-min LIU Cheng-rui Research Center of Small Sample Technology Beijing University of Aeronautics and Astronautics Beijing 100191 China Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control Engineering Beijing 100191 China

The small sample prediction problem which commonly exists in reliability analysis was discussed with the progressive prediction method in this *** modeling and estimation procedure,as well as the forecast and confidence limits formula of the progressive auto regressive(PAR) method were discussed in great *** model not only inherits the simple linear features of auto regressive(AR) model,but also has applicability for nonlinear *** application was illustrated for predicting the future fatigue failure for Tantalum electrolytic *** results of PAR model were compared with auto regressive moving average(ARMA) model,and it can be seen that the PAR method can be considered good and shows a promise for future applications.

关键词： failure data forecast system reliability small sample progressive prediction nonlinear system

Comparison of two reliability models for performance degradation analysis

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航空动力学报 2015年第7期30卷 1632-1637页

作者： WANG Zhi-hua ZANG Guang-kui ZHANG Yong-bo fu hui-min Research Center of Small Sample Technology Beijing University of Aeronautics and Astronautics

In order to investigate the general reliability assessment methods based on performance degradation data,two commonly used stochastic process approaches,bilinear process method and random-effect model were *** procedure and effectiveness of these two methodologies were studied and ***,the two approaches were illustrated through practical *** residual plots and the 10th percentile curves of the two methods were presented to demonstrate the comparative *** randomeffect model yielded more volatile residuals and a lower and unsafe 10th percentile *** the bilinear process model can be concluded to derive more reasonable results due to its one-stage estimation property.

关键词： degradation analysis reliability assessment stochastic process bilinear independent increment process random-effect model

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小样本积木式可靠性评估与更新方法

机电产品开发与创新 2024年第2期37卷 1-5页

作者：傅惠民李子昂付越帅郭建超北京航空航天大学小样本技术研究中心

针对工程上只能进行极少甚至无法进行整机寿命试验，导致可靠性评估精度不高的情况，提出一种小样本积木式可靠性评估与更新方法。首先建立了能够根据机电产品子系统当前试验、以往试验和以往服役寿命数据，对其整机高置信度、高可靠度... 详细信息

针对工程上只能进行极少甚至无法进行整机寿命试验，导致可靠性评估精度不高的情况，提出一种小样本积木式可靠性评估与更新方法。首先建立了能够根据机电产品子系统当前试验、以往试验和以往服役寿命数据，对其整机高置信度、高可靠度的可靠寿命进行评估的方法，从而解决了机电产品无法进行整机寿命试验时的可靠性评估难题，为其外场使用提供了科学依据。然后给出了能够根据该机电产品整机试验寿命数据和外场服役寿命数据对上述可靠寿命评估结果进行更新的方法，从而增大了信息量，显著提高其可靠性评估精度。文中针对工程上常用的指数分布、 Weibull分布和对数正态分布情况进行了详细讨论，给出了相应的整机高置信度、高可靠度的可靠寿命评估与更新公式。

关键词：电子产品机械产品机电产品可靠性评估可靠性更新小样本积木式

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多应力小样本加速寿命试验设计与评估方法

机电产品开发与创新 2024年第3期37卷 1-4页

作者：傅惠民郭建超付越帅李子昂北京航空航天大学小样本技术研究中心

针对目前多应力加速寿命试验需要的组合应力水平多、时间长、费用高的问题，提出一种多应力小样本加速寿命试验设计与评估方法。该方法建立了正常使用应力水平下可靠寿命的单侧置信下限与加速应力水平下的可靠寿命置信限之间的数学关系... 详细信息

针对目前多应力加速寿命试验需要的组合应力水平多、时间长、费用高的问题，提出一种多应力小样本加速寿命试验设计与评估方法。该方法建立了正常使用应力水平下可靠寿命的单侧置信下限与加速应力水平下的可靠寿命置信限之间的数学关系式，给出了正常使用应力水平下高置信度、高可靠度的可靠寿命单侧置信下限计算公式。文中首先针对工程上最常用的双应力情况，分别建立了无耦合和有耦合的双应力小样本加速寿命试验设计与评估方法，它只需在三个（无耦合）或四个（有耦合）组合应力水平下进行加速寿命试验，即可对产品在正常使用应力水平下高置信度、高可靠度的可靠寿命进行评估。然后针对一般的m种应力情况，建立了基于多应力线性加速模型的小样本加速寿命试验设计与评估方法，它只需在m+1个组合应力水平下进行加速寿命试验，即可求得产品在正常使用应力水平下高置信度、高可靠度的可靠寿命单侧置信下限。该方法计算简单，而且对完全数据、不完全数据以及各种分布均适用。大量工程算例和Monte Carlo模拟验证表明，与传统多应力加速寿命试验方法相比，本文方法不但可以节省大量试样和试验时间，而且理论上更加严谨，精度更高。

关键词：多应力加速寿命试验小样本试验设计可靠寿命置信限

来源：博看期刊

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小样本加速寿命试验设计与评估方法

机电产品开发与创新 2024年第1期37卷 1-5页

作者：傅惠民郭建超付越帅李子昂北京航空航天大学小样本技术研究中心

针对工程上加速寿命试验仍然存在时间长、试样多的问题，提出一种小样本加速寿命试验设计与评估方法。该方法只需在两个加速应力水平下进行加速寿命试验，即可对产品在正常使用应力水平下高置信度、高可靠度的可靠寿命进行评估。文中首... 详细信息

针对工程上加速寿命试验仍然存在时间长、试样多的问题，提出一种小样本加速寿命试验设计与评估方法。该方法只需在两个加速应力水平下进行加速寿命试验，即可对产品在正常使用应力水平下高置信度、高可靠度的可靠寿命进行评估。文中首先利用工程上常用的线性加速模型（如阿伦尼斯模型、逆幂律模型和指数模型等）建立了正常使用应力水平下可靠寿命的单侧置信下限与两个加速应力水平下的可靠寿命置信限之间的数学关系式，给出了正常使用应力水平下高置信度、高可靠度的可靠寿命单侧置信下限评估方法。然后分别对指数分布、两参数Weibull分布和对数正态分布的定数截尾加速寿命试验情况进行了详细讨论，给出了相应的正常使用应力水平下高置信度、高可靠度的可靠寿命单侧置信下限计算公式。该方法计算简单，而且对完全数据、不完全数据以及各种分布均适用。大量工程算例和Monte Carlo模拟验证表明，与需要在多个加速应力水平下进行寿命试验的传统方法相比，本文方法不但可以节省大量试样和试验时间，而且理论上更加严谨，精度更高。

关键词：加速寿命试验小样本试验设计可靠性评估寿命预测置信下限

来源：博看期刊