SIX SIGMA: WHERE THE CONCEPT HAS GENERATED Some researchers have claimed that Six Sigma quality initiative was started in the mid-1960s. Historically, the roots of Sigma as a measurement standard can be traced to Carl Fredrick Gauss (1777-1855), who introduced the concept of normal curve. Walter Shewart introduced 'three sigma' as a measurement of output variation in 1922 and stated that process intervention was needed when the output went beyond this limit. The 'three sigma' concept is related to a process yield of 99.973% and represents a defect rate of 2,600 per million which was adequate for most manufacturing organizations until the early 1980s. Henderson and Evans (2000) have found that Motorola first embarked on its Six Sigma quality initiative in the mid-1960s and the concept of implementing Six Sigma processes was pioneered at Motorola in the 1980s. In addition, Dedhia (2005) and Park (2002) have claimed that Bill Smith at Motorola, during the late 19...
This blog is specially developed to help mechanical engineering students, working mechanical professionals. There is multiple section to cater them. This included notes section, GATE/IES preparation section, Resume writing section and Project/thesis section.