İKI-AŞAMALI ARAÇ ROTALAMA PROBLEMİ: TEMEL YAKLAŞIMLAR VE KONVANSİYONEL ARAÇ ROTALAMA PROBLEMİ İLE KARŞILAŞTIRMALAR

Öz

Dağıtım ağının birden fazla kademeye bölündüğü çok-aşamalı dağıtım sistemleri, işletmelerin hem ilk kademelerde gerçekleştirdikleri büyük miktarlardaki sevkiyatlardan hem de her kademedeki araç kapasitelerinin etkin kullanımından doğan ölçek ekonomilerinden faydalanmalarını ve yoğun kentsel alanlarda gerçekleştirilen dağıtım faaliyetlerinden kaynaklanan çevresel ve sosyal etkilerin azaltılmasını sağlayabilmektedir. Bu bağlamda, akademik literatürde de çok-kademeli dağıtım sistemlerinin modellenmesine yönelik çalışmalar da artmaktadır. Bu çalışmanın amacı, çok-kademeli dağıtım sistemleri kapsamında yer alan İki-Aşamalı Araç Rotalama Problemine (2A-ARP) kapsamlı bir bakış açısı sunmak ve tek-kademeli dağıtım sistemlerine göre avantajlarını irdelemektir. Bu amaçlar doğrultusunda, literatürde yer alan 2A-ARP uygulamaları çözüm yaklaşımları açısından sınıflandırılarak metodolojik detayları tasnif edilmekte, daha sonra, bir süpermarket zincirinin verisinden hareketle oluşturulan uygulama tasarımı ile 2A-ARP modellemesi klasik Araç Rotalama Problemi (ARP) ile mesafe, yakıt tüketimi, süre ve maliyet gibi dört ayrı amaç fonksiyonu ile kıyaslamaya tabi tutulmaktadır. Kıyaslamalarda, kapasite, talep, araç sayısı ve araç kapasitesi parametrelerindeki değişimin etkisini analiz etmek amacıyla 25 senaryo ile duyarlılık analizi yapılmıştır. Tasarlanan uygulama varsayımları altında elde edilen sonuçlar, 2A-ARP modelinin ARP modeline göre daha maliyetli olmasına rağmen, süre, mesafe ve yakıt tüketimi gibi faktörler açısından daha avantajlı olduğunu göstermektedir.

Anahtar Kelimeler

• Lojistik
• Dağıtım
• Araç Rotalama Problemi (ARP)
• İki-Aşamalı Araç Rotalama Problemi (2A-ARP)

TWO-ECHELON VEHICLE ROUTING PROBLEM: REVIEW AND COMPARISONS WITH CONVENTIONAL VEHICLE ROUTING PROBLEM

Öz

Multi-stage distribution systems, in which the distribution network is divided into more than one level, can enable businesses to benefit from the economies of scale arising from both large quantities of shipments at the first stages and the efficient use of vehicle capacities at all levels, and to reduce environmental and social impacts from distribution activities carried out in dense urban areas. In this context, there is an increasing interest in modeling multi-stage distribution systems in the academic literature. This research aims to provide a comprehensive look at the Two-Echelon Vehicle Routing Problem (2E-VRP) that is within the scope of multi-stage distribution systems and to examine its advantages over single-stage distribution systems. In line with these purposes, we classify 2E-VRP applications in terms of solution approaches and their methodological details, then, we design an application and compare 2E-VRP modeling with the classical Vehicle Routing Problem (VRP) using four different objective functions like distance, fuel consumption, time and cost. A sensitivity analysis is conducted with 25 scenarios to analyze the effect of changes in capacity, demand, number of vehicles, and vehicle capacity parameters. The results reveal that although the 2E-VRP model is costlier than the VRP model, it is more advantageous in terms of factors such as time, distance, and fuel consumption.

Anahtar Kelimeler

• Logistics
• Distribution
• Vehicle Routing Problem (VRP)
• Two-Echelon Vehicle Routing Problem (2E-VRP)
• Logistics, Distribution, Vehicle Routing Problem (VRP), Two-Echelon Vehicle Routing Problem (2E-VRP)

Kaynakça

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