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Lifetime prediction based on Gamma processes from accelerated degradation data

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Chinese Journal of Aeronautics 2015年第1期28卷 172-179页

作者： Wang Haowei Xu Tingxue Mi Qiaoli graduate Students’ Brigade Naval Aeronautical and Astronautical University Department of Ordnance Science and Technology Naval Aeronautical and Astronautical University

Accelerated degradation test is a useful approach to predict the product lifetime at the normal use stress level, especially for highly reliable products. Two kinds of the lifetime prediction based on Gamma processes were studied. One was to predict the lifetime of the population from accelerated degradation data, and the other was to predict the lifetime of an individual by taking the accelerated degradation data as prior information. For an extensive application, the Gamma process with a time transformation and random effects was considered. A novel contribution is that a deducing method for determining the relationships between the shape and scale parameters of Gamma processes and accelerated stresses was presented. When predicting the lifetime of an individual, Bayesian inference methods were adopted to improve the prediction accuracy, in which the conjugate prior distribution and the non-conjugate prior distribution of random parameters were studied. The conjugate prior distribution only considers the random effect of the scale parameter while the non-conjugate prior distribution considers the random effects of both the scale and shape parameter. The application and usefulness of the proposed method was demonstrated by the accelerated degradation data of carbon-film resistors.

关键词： conjugate accelerated prior lifetime Bayesian determining illustrated likelihood acceleration fitting

第一届Rodney Hill奖获得者Michael Ortiz教授研究工作简评

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力学进展 2008年第5期38卷 625-626页

作者：黎波 graduate aeronautical laboratories California Institute of Technology

Michael Ortiz是加州理工学院航窄与机械工程Dotty和DickHayman教授，关国文理研究院院上，由于其存1998—2007年间的出色研究成果荣获ICTAM2008年度RodneyHill奖．RodneyHill固体力学奖和Batch-elor流体力学奖是国际理论与应用力学联... 详细信息

Michael Ortiz是加州理工学院航窄与机械工程Dotty和DickHayman教授，关国文理研究院院上，由于其存1998—2007年间的出色研究成果荣获ICTAM2008年度RodneyHill奖．RodneyHill固体力学奖和Batch-elor流体力学奖是国际理论与应用力学联合会（International Union of Theoretical and Applied Mechanics，IUTAM）设立的，旨在表彰获奖者过去10年中存其力学分支学科研究中所取得的重要贞献．Ortiz教授是RodneyHill奖的第一位获奖人．

关键词： Michael 获得者加州理工学院应用力学机械工程流体力学固体力学研究成果

Saturation attack based route planning and threat avoidance algorithm for cruise missiles

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Journal of Systems Engineering and Electronics 2011年第6期22卷 948-953页

作者： Guanghui Wang Xuefeng Sun Liping Zhang Chao Lv Department of Command Naval Aeronautical and Astronautical University Yantai 264001 P. R. China graduate Student Brigade Naval Aeronautical and Astronautical University Yantai 264001 P. R. China

According to the characteristic of cruise missiles,navigation point setting is simplified,and the principle of route planning for saturation attack and a concept of reference route are put *** the help of the shortest-tangent idea in route-planning and the algorithm of back reasoning from targets,a reference route algorithm is built on the shortest range and threat *** a route-flight-time algorithm is built on navigation *** on the conditions of multi-direction saturation attack,a route planning algorithm of multi-direction saturation attack is built on reference route,route-flight-time,and impact *** results show that the algorithm can realize missiles fired in a salvo launch reaching the target simultaneously from different directions while avoiding threat.

关键词： aerospace system engineering control and navigation technology of aero-craft mission planning route planning cruise missile saturation attack threat avoidance.

Analysis of moisture distribution within composite materials in hygrothermal environment

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Analysis of moisture distribution within composite materials...

Applicability of the Time-Temperature Superposition Principle in Modeling Dynamic Response of a Polyurea

第八届中国功能材料及其应用学术会议

作者： JIN Ping WANG De TAN Xiao-ming Qingdao Branch of Naval aeronautical Engineering Institute graduate Students Brigade of Naval aeronautical Engineering Institute

ISBN: (纸本)9783037859698

The moisture absorption behavior of CCF300/BA9916 composites in 70℃ distilled water *** on the moisture absorption experiments,the moisture diffusivity and solubility were gained for FEM *** experiments results show that the moisture absorption behavior of CCF300/BA9916 composites basically conforms the Fickian’s second *** simulation results were coincided with the experimental data,the long-term absorption behavior and moisture distribution concentrations within the specimen were obtained.

关键词： Composites Moisture environment Distribution concentration

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Applicability of the Time-Temperature Superposition Principl...

Design and validation of a variable camber wing structure

中国力学学会学术大会'2009

作者： Knauss WG Ravichandran G graduate aeronautical laboratories California Institute of Technology

This paper addresses the applicability of the Time-Temperature Superposition Principle in the dynamic response of a polyurea polymer at high strain rates and different *** and extensive measurements in the time domain... 详细信息

关键词： viscoelasticity time-temperature superposition master curve high strain rates Hopkinson bar

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Chinese Journal of Aeronautics 2024年第2期37卷 1-11页

作者： Xiasheng SUN Jingfeng XUE Jin ZHOU Zhigang WANG Wenjuan WANG Mengjie ZHANG Chinese aeronautical Establishment Beijing 100012China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Aircraft Strength Research Institute of China Xi’an 710065China graduate School of Chinese aeronautical Establishment Yangzhou 225002China

Variable camber wing technology is one of the important development trends of green aviation at *** smooth,seamless,continuous and adaptive change of wing camber,the aerodynamic performance is improved in achieving increase in lift and reduction in resistance and *** on the aerodynamic validation model CAE-AVM,Chinese aeronautical Establishment(CAE)has carried out the design and validation of a variable camber wing,proposed an aerodynamic deformation matrix for the leading and trailing edges of aircraft wings in takeoff,landing and cruise *** structures and driving schemes are compared,and several key technology problems of leading and trailing edge deformation are solved.A full-size leading edge wind tunnel test piece with a span of 2.7 m and a trailing edge ground function test piece are *** deformation and shape maintenance capabilities of the leading edge is verified under real wind load conditions,and the load bearing and deformation capabilities of the trailing edge is verified under simulated follow-on *** results indicate that the leading and trailing edges of the variable camber wing can achieve the required deformation angle and have a certain load-bearing *** study can provide some insights into the application of variable camber wing technology for civil aircraft.

关键词： Variable camber wing Leading edge Trailing edge Structure Measurement and control Test

THE STATIC AND DYNAMIC MECHANICAL BEHAVIOR OF DENSE AND POROUS Ti2AIC

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THE STATIC AND DYNAMIC MECHANICAL BEHAVIOR OF DENSE AND PORO...

Fast pore etching on high resistivity n-type silicon via photoelectrochemistry

庆祝中国力学学会成立50周年暨中国力学学会学术大会’2007

作者： POONB RAVICHANDRAN G graduate aeronautical laboratories California Institute of Technology

The mechanical behavior of dense and porous TiAlC(MAX material) has been characterized in the quasi-static and dynamic loading *** monotonic quasi-static stress-strain relationship can be described by a *** the material is cyclically loaded beyond the yield point,hysteresis loops are observed similar to those described in Ref.,with a clear tendency to cyclically *** experiments showed no

关键词：

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Chinese Physics B 2009年第2期18卷 664-670页

作者：包晓清葛道晗张圣李金鹏周萍焦继伟王跃林 State Key laboratories of Transducer Technology National Key Laboratories of Microsystem Technology Shanghai Institute of Microsystem and Information Chinese Academy of Sciences graduate School of Chinese Academy of Sciences

In this paper, five factors, namely the HF （hydrofluoric acid） concentration, field strength, illumination intensity as well as the oxidizing-power and conductivity of electrolytes were found to strongly affect the fast pore etching. The oxidizing power of aqueous HF electrolyte of different concentrations was especially measured and analysed. A positive correlation between optimal bias and HF concentration was generally observed and the relationship was semiquantitatively interpreted. Pore density notably increased with enhanced HF-concentration or bias even on patterned substrates where 2D （two-dimensional） nuclei were densely pre-textured. The etch rate can reach 400μm/h and the aspect ratio of pores can be readily driven up to 250.

关键词： pore density SCR width H-passivation current-burst-model breakdown mechanism

Observation of a diverse deviation from macropore-formation theory in silicon electrochemistry

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Chinese Physics B 2008年第8期17卷 3130-3137页

作者：包晓清葛道晗焦继伟 State Key laboratories of Transducer Technology National Key Laboratories of Microsystem Technology Shanghai Institute of Microsystem and Information Chinese Academy of Sciences graduate School of Chinese Academy of Sciences

Via anodizing patterned and unpatterned samples with a high HF concentration （[HF]）, the degree of deviation from pore-formation theory was found to be markedly different. Based on the analysis of scanning electron microscope （SEM） micrographs and current-voltage （I - V） curves, the variation of physical and chemical parameters of patterned and unpatterned substrates was found to be crucial to the understanding of the observations. Our results indicate that the initial surface morphology of samples can have a considerable influence upon pore formation. The electric-field effect as well as current-burst-model was employed to interpret the underlying mechanism.

关键词： space charge region point nuclei unpatterned specimen I - V curve