過程能力培訓教程(英文版)(ppt 55頁)
過程能力培訓教程目錄:
1、Variation, Tolerances and Dimensional Control.................4
2、Population, Sample and Normal Distribution....................15
3、Cp and Cpk Concept............................................28
4、Use of the NMP Data Collection Spreadsheet....................44
5、Confidence of Cpk.............................................52
過程能力培訓教程內容摘要:
Two Types of Product Characteristics
Variable: A characteristic measured in physical units, e.g. millimetres, volts, amps, decibel and seconds.
Attribute: A characteristic that by comparison to some standard is judged “good” or “bad”, e.g. free from scratches (visual quality).
Two Types of Processes:
All processes have:
Natural (random) variability
=> due to common causes
Unnatural variability
=> due to special causes
Stable Process:
A process in which variation in outcomes arises only from common causes
Unstable Process:
A process in which variation is a result of both common and special causes
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