|
|
Journal of Korean Society for Quality Management 2004;32(4): 156-. |
| 두 개의 이상원인이 존재하는 공정에 대한 VSSI $ar{X}$ 관리도의 통계적 효율성 |
| 이호중, 임태진 |
| 숭실대학교 산업ㆍ정보시스템공학과 |
| Statistical Efficiency of VSSI $ar{X}$ Control Charts for the Process with Two Assignable Causes |
|
|
|
|
|
|
| ABSTRACT |
|
This research investigates the statistical efficiency of variable sampling size & sampling interval(VSSI) $ar{X}$ charts under two assignable causes. Algorithms for calculating the average run length(ARL) and average time to signal(ATS) of the VSSI $ar{X}$ chart are proposed by employing Markov chain method. States of the process are defined according to the process characteristics after the occurrence of an assignable cause. Transition probabilities are carefully derived from the state definition. Statistical properties of the proposed chart are also investigated. A simple procedure for designing the proposed chart is presented based on the properties. Extensive sensitivity analyses show that the VSSI $ar{X}$ chart is superior to the VSS or VSI $ar{X}$ chart as well as to the Shewhart $ar{X}$ chart in statistical sense, even tinder two assignable causes. |
| Key Words:
VSSI control chart;ARL;ATS;statistical design;Markov chain;steady state solution; |
|
|
|
PDF Links
Full text via DOI 
Download Citation 
