1 / 15

SXC control chart

SXC control chart. 指導教授：童超塵 作者： Zhang Wu, Ming Xie, Qingchuan Lin and Yu Zhang 主講人：廖莉芳. The International Journal of Advanced Manufacturing Technology Volume 30, Numbers 5-6 / September, 2006. Outline. Introduction Design of the SXC chart

sylvia
Télécharger la présentation

SXC control chart

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. SXC control chart 指導教授：童超塵 作者：Zhang Wu, Ming Xie, Qingchuan Lin and Yu Zhang 主講人：廖莉芳 The International Journal of Advanced Manufacturing Technology Volume 30, Numbers 5-6 / September, 2006

  2. Outline • Introduction • Design of the SXC chart • Comparative studies • Conclusions and discussions

  3. Introduction • SXC (sum of xs with curtailment) control chart. • as simple as the X-bar chart ; as effective as the CUSUM chart

  4. Design of the SXC chart • Some parameters need to be specified: • Calculation of ATS • Two key samples： • Shifting sample – mean shift takes place • Signalling sample – mean shift is detected

  5. Design of the SXC chart • The steps for calculating ATS are outlined below. (1) Calculate p(m) • p(m) is the probability that the mean shift is detected after inspecting the mth unit in the signalling sample (2) Calculate Q • Q is the probability that the out-of-control condition is detected in a single sample. (3) Calculate q • q is the average number of units inspected in the signalling sample. (4) Finally,compute ATS

  6. Design of the SXC chart

  7. Design of the SXC chart • The optimization design of the SXC chart • How to choose n? • The sample size n will be increased from Nmin in step of one until ATS can not be further reduced. • The steps are outlined below:

  8. Design of the SXC chart

  9. Comparative studies • Compares the performance of three control, X-bar chart、CUSUM chart and the SXC chart. • The sample size and control limits of all the charts are determined by the same optimization model. • Nmin =4 • Study one • τ=1850 (ARL0=370 and n=5) • 0.0≦δ ≦3.4

  10. Comparative studies • There are several interesting findings： • ATS0 that are very close toτ (=1850) • very similar false alarm rates • When the mean shift becomes large, the curtailment mechanism enables the SXC chart to signal the out-of-control condition before all of the n units in a sample are inspected. • The ATS values of the two charts do not differ significantly for any given mean shift value.

  11. average ratio

  12. Study two

  13. Conclusions and discussions • SXC 管制圖比X-bar管制圖好，平均可縮短74％的ATS。 • 雖然SXC跟CUSUM管制圖效率差不多，但是SXC管制圖比較簡單。 • 即使換成random inspection或uniform inspection 結果也差不多。 • 也許可以將相同的手法用在R或其他管制圖上

More Related