Örnek Bir Tedarik Zincirinin Sistem Dinamikleri Yaklaşımı İle Modellenmesi

Year 2011, Volume: 3 Issue: 1, 2 - 10, 15.01.2011

Murat Yegengil Hakan Arslan Ata Sevinç

Abstract

Küreselleşme ile birlikte değişen işletmecilik şartları, mesela sınırsız sayılabilecek kapasite, sıfır tedarik süreleri, genişleyen pazarlar, tedarikçi sayısında artış, hızlı iletişim gibi, Tedarik Zinciri Yönetimi’nin artan ehemmiyetini ortaya koymaktadır. Özellikle malzeme ve bilgi kaynaklarına hızlı ulaşım ve alternatif tedarikçi bulmadaki kolaylıklar yeni stok politikalarının geliştirilmesini zorunlu hale getirmektedir. Bu çalışmada, tedarik zinciri sisteminde stok yönetimi “sistem dinamikleri” yaklaşımı kullanılarak Matlab/Simulink ortamında modellenmiş ve geleneksel stok modellerine ilave olarak yeni bir “kesikli zaman sürekli gözden geçirmeli” stok yönteminin geliştirilmesi üzerinde çalışılmıştır. Bu arada esas itibarıyla bir klasik kontrol yöntemi olan “PID kontrol “ yönteminin bağımsız bir stok modeli olarak kullanılması üzerinde çalışılmıştır. tasarlanan çok kademeli (multi-echelon) Tedarik Zinciri modelinde PID politikası En küçük-En büyük (s-S) ve Ekonomik Sipariş Miktarı (EOQ) stok politikaları ile karşılaştırılmıştır. PID yöntemi ESM ve s-S arasında bir ortalama stok değeri vermiştir. Son olarak, geliştirilen modele ait blok diyagramları, kesikli sistem benzetimi için z-transfer fonksiyonunun bulunmasında ve analiz amaçlı olarak kullanılabilir.

Keywords

System Dinamikleri, Tedarik Zinciri Yönetimi, PID Control, PID Stok Kontrol Yöntemi

Örnek Bir Tedarik Zincirinin Sistem Dinamikleri Yaklaşımı İle Modellenmesi

Abstract

Business conditions have been re-shaped by globalization, for example infinite capacity, zero lead times expanding markets, increase in number of suppliers, and faster communications, which increases importance of Supply Chain Management. Especially increased speed at reach to material and information resources along with ease at finding alternative suppliers necessitates development of new stock policies. In this study, stock management in Supply Chain will be modeled under Matlab/Simulink environment by use of “System’s Dynamics” approach and worked towards developing a new “discrete time continuous review” stock model in addition to traditional models. PID, Minimum-Maximum (s-S), and EOQ policies have been compared within the designed multi-echelon supply chain model. PID has generated a mean stock value between EOQ and s-S methods. Finally, block diagrams of the designed model can be used to find transfer functions for discrete time simulation, which can be used for analysis purposes.

Keywords

System Dynamics, Supply Chain Management, PID Control, PID Stock Control Method

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