This article focuses on failure modes and lifetime testing of IGBT modules being one the most vulnerable components in power electronic converters. have already located themselves heart many critical applications, such as automotive, aerospace, transportation, energy. They are required to work under harsh operational environmental conditions for extended target that may reach 30 40 years some a...

The Weibull distribution is a very applicable model for the lifetime data. For inference about two Weibull distributions using records, the shape parameters of the distributions are usually considered equal. However, there is not an appropriate method for comparing the shape parameters in the literature. Therefore, comparing the shape parameters of two Weibull distributions is very important. I...

OBJECTIVE Genetic testing for gene mutations associated with specific cancers provides an opportunity for early detection, surveillance, and intervention (Smith, Cokkinides, & Brawley, 2008). Lifetime risk estimates provided by genetic testing refer to the risk of developing a specific disease within one's lifetime, and evidence suggests that this is important for the medical choices people mak...

in the last decade, decrease of the wear rate, increase in the axel load, and the velocity of the trains have changed the main damage mechanism of railway wheels from wear to rolling contact fatigue (rcf). rcf may lead to surface and subsurface cracks. the interaction between wear and rcf, removes the surface cracks, but the subsurface crack propagate gradually, and may lead to deeper and more ...

Over the last few years a theoretical treatment for the weak decays of heavy-flavour hadrons has been developed that is genuinely based on QCD. Its methodology is described as it applies to total lifetimes, and the underlying theoretical issues are discussed. Theoretical expectations are compared with present data. One discrepancy emerges: the beauty baryon lifetime appears to be significantly ...

By running the life tests at higher stress levels than normal operating conditions, accelerated life testing quickly yields information on the lifetime distribution of a test unit. The lifetime at the design stress is then estimated through extrapolation using a regression model. In constant-stress testing, a unit is tested at a fixed stress level until failure or the termination time point of ...