Abstract:

This issue mainly comprises case studies and success stories in the area of performability engineering and Six Sigma from large and reputed organizations and companies. The first five papers constitute a section organized by Mr Thimmiah Gurunatha, who is a Fellow of ASQ and is on the Reliability and Maintainability Symposium Board of Directors and a master black belt Six Sigma. This section highlights the success stories from different organizations and companies in implementing reliability programmes and to emphasize the importance of Six Sigma. I am thankful to him for having accepted our invitation to organize this section. The last two papers also present a case study from ALSTOM and the successful business strategy of some multinationals in India in the automobile sector, respectively. We do hope that in future we will be able to present more success stories and case studies for the benefit of readers and subscribers of the International Journal of Performability Engineering.

The origin of the concept of Six Sigma can be traced back to the 1920's when Walter Shewhart showed that three sigma from the mean is a point where a process requires correction. Many measurement standards (Cpk, Zero Defects, etc.) later appeared on the scene but credit for Six Sigma (which also happens to be the trade mark of Motorola) goes to a Motorola engineer named Bill Smith. During 1980s, Motorola engineers decided that the traditional quality levels - measuring defects in thousands of opportunities wasn't adequate enough and they wanted to measure the defects per million opportunities. Motorola developed this new standard and created a methodology and the necessary cultural change associated with it.? Six Sigma helped Motorola save more than $16 billion over 11 years as a result of their Six Sigma efforts. Since then, several companies around the world have adopted Six Sigma as a way of conducting business. American companies like General Electric and Honeywell have also adopted and implemented Six Sigma in their businesses, and they claim to have made considerable savings to the order of $ 2 billion and $ 1.2 billion, respectively. Six Sigma naturally has evolved over time. It is more than just a quality system in manufacturing and services like TQM, SPC, PLM, ISO¹, etc., in fact it is a way of doing business. It can not only be used as operational strategy to reduce defects or as a business strategy to improve market share, but also to evolve new business models and profitability. Six Sigma can be used as a vision; a philosophy; a symbol; a metric; a goal; a methodology.

The Design for Six Sigma (DFSS) uses Six Sigma as a strategy to design and develop new products. DMAIC, which stands for 5 stages, viz., define, measure, analyze, improve and control, is at the heart of all Six Sigma projects. Lean Six Sigma combines lean concepts with Six Sigma.

In addition to the success stories and case studies presented in this issue, the editor would like to draw the attention of IJPE readers to the two books that are being reviewed in this issue. They are some of the best titles brought out by Earthscan and must be read by those who are concerned with the reliability and risk assessment, particularly, as they deal with the subject of uncertainties in new perspective and risk governance in totality.

1? Handbook of Performability Engineerng, K.B.Misra (Ed.), 76 chapters, pp. 1315, Springer, 2008.