Rịba ama amaokwu a dị n'okpuru ma zaa ajụjụ ahụ mgbe e mesịrị n'otu asụsụ ahụ dị ka amaokwu ahụ:  Passage: Walter A. Shewhart malitere SPC na Bell Laboratories na mbido afọ 1920. Shewhart mepụtara eserese njikwa na 1924 na echiche nke steeti njikwa ọnụ ọgụgụ. Nchịkwa ọnụ ọgụgụ bụ ihe kwekọrọ n'echiche nke mgbanwe nke onye ọkà mmụta ihe ọmụma bụ William Ernest Johnson mepụtara n'afọ 1924 n'akwụkwọ ya bụ Logic, Part III: The Logical Foundations of Science. Ya na ndị otu na AT&T nke gụnyere Harold Dodge na Harry Romig ọ rụrụ ọrụ iji tinye nyocha nlele na ndabere nke ọgụgụ isi. Shewhart gakwuuru Colonel Leslie E. Simon n'ihe gbasara itinye chaatị njikwa n'ọrụ maka imepụta ogbunigwe na Picatinny Arsenal nke ndị agha na 1934. Ngwa ahụ gara nke ọma nyere aka mee ka ndị agha agha kweta itinye aka na AT & T's George Edwards ka ha na-atụle maka iji njikwa njikwa ọnụ ọgụgụ dị n'etiti ngalaba ya na ndị ọrụ nkwekọrịta na mmalite nke Agha Worldwa nke Abụọ.  Ajụjụ: Walter Shewhart ọsụ ụzọ SPC?
Ụlọ nyocha Bell