THE EFFECT OF FIXED PRODUCTION SETUP COST ON INVENTORY OPTIMISATION UNDER PROCESS FLEXIBILITY

Öz

Process flexibility in manufacturing aims to produce different products at the same production facility with the minimum setup cost. It is not possible to completely eliminate the setup cost in most cases even if a high degree of investment is made for process flexibility. In this study, a decision support model accounting for fixed setup cost has been presented to make inventory decisions in production systems that have process flexibility. Additionally, under process flexibility, the effect of fixed setup cost on inventory decisions has been investigated. In this context, process flexibility problem with fixed setup cost has been modelled using Mixed Integer Linear Programming approach. Numerical assessments have been done on three different production systems (dedicated, two chain and flexible) by means of the proposed decision support model. The results reveal the necessity of taking fixed setup cost into account in decision support models for process flexibility problem.

SABİT ÜRETİM HAZIRLIK MALİYETİNİN SÜREÇ ESNEKLİĞİNDE STOK OPTİMİZASYONUNA ETKİSİ

Öz

Üretimde süreç esnekliği, farklı ürünlerin minimum hazırlık maliyetiyle aynı üretim tesisinde üretilmesini hedeflemektedir. Sabit üretim hazırlık maliyetinin tamamen ortadan kalkması süreç esnekliği için yüksek seviyede yatırım yapılsa bile, pek çok durumda mümkün değildir. Bu çalışmada, süreç esnekliğine sahip sistemlerde stok kararlarının verilmesi için sabit hazırlık maliyetlerini dikkate alan bir karar destek modeli sunulmuş ve sabit hazırlık maliyetlerinin süreç esnekliğinde stok kararlarına etkisi araştırılmıştır. Bu çerçevede süreç esnekliği problemi sabit hazırlık maliyeti göz önünde bulundurularak, karma tam sayılı doğrusal programlama yöntemiyle modellenmiştir. Geliştirilen bu karar destek modeli kullanılarak esnek olmayan, ikili zincir tasarımlı ve tam esnek olmak üzere üç farklı üretim sistemi üzerinde değerlendirmeler yapılmıştır. Elde edilen sonuçlar süreç esnekliği problemi için geliştirilen karar destek modellerinde sabit üretim hazırlık maliyetinin göz önünde bulundurulmasının gerekliliğini ortaya çıkarmaktadır.

 

Anahtar Kelimeler

• Üretim yönetimi,süreç esnekliği,stok optimizasyonu,sabit üretim hazırlık maliyeti,karma tam sayılı doğrusal programlama

Kaynakça

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