43. Frequency Lower control limit Size (Weight, length, speed, etc. ) Upper control limit ( b) In statistical control (c) Out of control. (a) In statistical control
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49. 選取合理樣本 (Rational Subgroups) 2. 瞬時法 (instant time method) :估計製程標準差最好的方法。 1. 合理樣本 (rational subgroups) :抽樣方式可使非機遇原因出現時 , 樣本組間發生差異之可能性為最大 , 而樣本組內發生差異之可能性為最小。 3. 定時法 (period of time method) :提供較佳的整體結果 , 品質報告上將更能表達出準確的品質情況。
52. Variation due to natural causes 17=UCL 16=Mean 15=LCL Variation due to assignable causes Variation due to assignable causes Out of control 1 2 3 4 5 6 7 8 9 10 11 12 Sample Number