توسعه روش‌های پایش ماتریس واریانس-کوواریانس چندمتغیره در فاز

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی کارشناسی ارشد، دانشکده مهندسی صنایع، دانشگاه علم و صنعت ایران.

2 استاد، دانشکده مهندسی صنایع، دانشگاه علم و صنعت ایران.

چکیده
در کنترل آماری فرایندهای چندمتغیره دو یا چند مشخصه کیفی باید به طور همزمان کنترل شوند. در کنترل چنین فرایندهایی، دستیابی به دو هدف عمده لازم است. هدف اول تشخیص وضعیتهای خارج از کنترل و هدف دوم شناسایی مشخصه های کیفی عامل انحراف، در زمان وقوع یک وضعیت خارج از کنترل میباشد. در این تحقیق راههای دستیابی به هدف اول بررسی شده و روش هایی برای پایش ماتریس واریانس کوواریانس چندمتغیره در فاز 2 ارائه شده است. هدف اصلی فاز 2 کشف سریع شیفت ها می‌باشد. در این مقاله، 2 روش برای پایش ماتریس واریانس کوواریانس چندمتغیره در فاز 2 ارائه شده و شیفت در یکی از مشخصههای کیفی مورد 1 (متوسط طول دنباله) و کشف ARL بررسی قرارگرفته است. نتایج شبیه سازی نشان می دهد که روش های پیشنهادی باعث کاهش سریع تر وضعیت خارج از کنترل می شوند.

کلیدواژه‌ها


عنوان مقاله English

Development of multivariate variance-covariance matrix monitoring methods in phase

نویسندگان English

Samina Kabuli 1
Rasoul Nourossana 2
1 Master's student, Faculty of Industrial Engineering, Iran University of Science and Technology.
2 Professor, Faculty of Industrial Engineering, Iran University of Science and Technology.
چکیده English

In the statistical control of multivariate processes, two or more quality characteristics must be controlled simultaneously. In controlling such processes, two main goals must be achieved. The first goal is to detect out-of-control conditions and the second goal is to identify the quality characteristics that cause the deviation when an out-of-control condition occurs. In this research, ways to achieve the first goal are investigated and methods for monitoring the multivariate variance-covariance matrix in phase 2 are presented. The main goal of phase 2 is to quickly detect shifts. In this paper, two methods for monitoring the multivariate variance-covariance matrix in phase 2 are presented and the shift in one of the quality characteristics of case 1 (average trail length) and the detection of ARL are investigated. Simulation results show that the proposed methods reduce the out-of-control condition more quickly.

کلیدواژه‌ها English

Multivariate process statistical control
Multivariate variance-covariance matrix monitoring
Average trail length
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