Mining reliability data

Case Studies in Reliability and Maintenance, edited by Wallace R. Blischke and D. N. Prabhakar Murthy, Wiley-Interscience (www.wiley.com/statistics), 2003. 662 pages. $105.

At 662 pages, this book weighs in on a wide range of reliability topics—including analyzing dragline loads at an Australian coal mine, calculating dike failure rates in the Netherlands, and optimizing the reliability of NASA's Space Interferometry Mission, set to launch in 2009.

Among such far-flung applications—the editors have collected 26 case studies in all—you'll find many with direct or indirect application to the reliability of electronic products. Of direct application is a section that addresses the occurrence of moisture-induced cracks in plastic surface-mount components during reflow soldering processes. Another discusses "virtual qualification" (which employs mathematical failure models to estimate life expectancy) of electronic products such as automotive electronic-control units.

But many other topics, as well, are at least indirectly relevant to electronic product test. A case study of accelerated life tests on mechanical springs, for example, discusses mathematical functions such as the Weibull distribution, which applies as well to accelerated life tests of mechanical components.

The book's final chapter provides a highly readable analysis of motorcycle warranties; the methods could apply to developing warranties for any complex system. The authors of this study comment that warranty analyses are complicated because "warranty claims data are generally error-prone, incomplete, highly censored, and difficult to analyze."

I found of particular interest a study of the use of evolutionary (genetic) algorithms to analyze the reliability of photocopiers, which can experience a range of electrical and mechanical failures (from occasional paper smudges to repeated paper jams) that can make it difficult to determine appropriate failure models.

The editors begin the book with a helpful introduction to reliability and maintenance fields and with helpful definitions of terms such as "good-as-new repair" (just what you think it is) and two different types of "different-from-new repair" (read the book to learn about these).