Esin Cumhur YALÇIN, Cenk ÖZLER, Ali Kemal ŞEHİRLİOĞLU

Süreç Verilerinin Normal Dağılışa Uymadığı Durumlarda Kullanılan Süreç Yetenek Analizi Yöntemleri Üzerine Bir Araştırma

Öz Süreç yetenek analizi, bir üretim sürecinin, üretilen ürünlere ait kalite karakteristikleri için belirlenen toleransları karşılama yeteneğini ölçmek için kullanılmaktadır. Literatürde ilk önerilmiş olan süreç yetenek indeksleri, süreç verilerinin normal dağılması, kalite karakteristiklerine ait toleransların simetrik olması ve sürecin kontrol altında olması varsayımları altında çalışmaktadır. Daha sonraki çalışmalarda, (i) süreç verilerinin normal dağıldığı ve toleransların asimetrik olduğu, (ii) süreç verilerinin asimetrik bir dağılıma uyduğu ve toleransların simetrik olduğu durumlar için bazı yetenek indeksleri önerildiği görülmektedir. Bu çalışmanın amacı, literatürdeki çalışmalardan farklı olarak, toleransların asimetrik ve süreç verilerinin dağılımının normal olmadığı durumlar için yeni bir süreç yetenek indeksi önermektir. Asimetrik toleranslı durumlarda, üretim süreci tarafından üretilmesi istenen bir asimetrik dağılımın ne olması gerektiğini bulmak ve üretim sürecinin gerçekte ürettiği verilerin bu istenen dağılıma ne kadar yaklaştığını belirlemek için Pearson dağılım ailesi ile çalışılmıştır. Önerilen indeksin çeşitli durumlarda gösterdiği performans örneklerle incelenmiştir.

Anahtar Kelimeler:

Asimetrik Tolerans, Asimetrik Dağılım, Süreç Yetenek İndeksi, Pearson Dağılım Ailesi

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