English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The main objective of accelerated life tests (ALTs) is to predict fractionfailings of products in the field. However, there are often discrepanciesbetween the predicted fraction failing from the lab testing data and that fromthe field failure data, due to the yet unobserved heterogeneities in usage andoperating conditions. Most previous research on ALT planning and data analysisignores the discrepancies, resulting in inferior test plans and biasedpredictions. In this paper we model the heterogeneous environments togetherwith their effects on the product failures as a frailty term to link the labfailure time distribution and field failure time distribution of a product. Weshow that in the presence of the heterogeneous operating conditions, the hazardrate function of the field failure time distribution exhibits a range ofshapes. Statistical inference procedure for the frailty models is developedwhen both the ALT data and the field failure data are available. Based on thefrailty models, optimal ALT plans aimed at predicting the field failure timedistribution are obtained. The developed methods are demonstrated through areal life example.

How do heterogeneities in operating environments affect field failure predictions and test planning?