Yerleştirme-rotalama problemi için iki aşamalı bir model: Covid-19 aşılarının dağıtımı

Yıl 2022, Cilt: 28 Sayı: 4, 559 - 568, 31.08.2022

Merhad Ay Bengü Akdoğan Elif Morrice Fidan Lale Özbakır

Öz

Ülkemizi ve tüm dünyayı etkisi altına almış olan Covid-19 virüsüne karşı yapılan aşı çalışmaları, modern dünyanın kitlesel olarak aşılanabilmesi için büyük bir lojistik problemi de yanında getirmektedir. mRNA ve inaktif virüs yöntemi gibi farklı yöntemlerle üretilen çeşitli aşılar şirketler tarafından her geçen gün seri üretim için hazır hale getirilmektedir. Farklı koşullar altında farklı raf ömrü sürelerine sahip bu aşılar için iyi planlanmış bir dağıtım ağı büyük önem taşımaktadır. Bu çalışmada, ülkemizde kullanılan ve zorlu saklama koşullarına ihtiyaç duyan Covid-19 mRNA aşıları için raf ömrünü verimli şekilde kullanacak iki aşamalı yerleştirme-rotalama modeli üzerinde durulmaktadır. Bu açıdan çalışmada, iki farklı yöntem ile ara depolar ve ara depolara bağlı merkezler belirlenmiş, sonrasında ise belirlenen lokasyonlar arasındaki araç rotaları için probleme özgü zaman kısıtlı kapasiteli araç rotalama problemi matematiksel modeli geliştirilmiştir. Sonuç olarak ortaya çıkan iki aşamalı yerleştirme-rotalama modeli başarılı bir şekilde aşıların raf ömrü süresi dolmadan tüketilmesi için uygun dağıtım modelini tespit etmeyi mümkün kılmıştır. Tıp alanındaki bilim insanları, ilerleyen yıllarda da bu tarz salgınlarla tekrar karşılaşılacağını dile getirmektedir. Bu yüzden yapılan çalışma ileriki yıllarda daha da geliştirilerek ülkedeki aşı gibi acil ve kısa tüketim ömrüne sahip ürünlerin dağıtım politikasının önceden hazır ve etkin kılınmasını sağlayacaktır.

Anahtar Kelimeler

Yerleştirme-Rotalama, Covid-19, K-ortalamalar, P-Medyan

A two-echelon model for the location-routing problem: distribution of Covid-19 vaccines

Öz

Vaccination studies against the Covid-19 virus, which has affected our country and the whole world, bring along a major logistical problem for the mass vaccination of the modern world. Various vaccines produced by different methods such as mRNA and inactive virus method are made ready for mass production by companies. A well-planned distribution network is important for these vaccines with different shelf life under different conditions. In this study, the two-echelon location-routing model that will efficiently use the shelf life for Covid-19 mRNA vaccines, which are used in our country and need harsh storage conditions, is emphasized. In this respect, hubs and centers were determined with two different methods, and then time-limited capacitated vehicle routing problem mathematical model was developed for vehicle routes between the determined locations. As a result, two-stage deployment-routing model made it possible to successfully identify the appropriate delivery model for vaccines to be consumed before the shelf-life period. Scientists in the field of medicine state that such epidemics will be encountered again in the coming years. Therefore, the study will be developed further in the following years and will ensure that the vaccine distribution policy in the country is ready and effective in advance.

Anahtar Kelimeler

Location-Routing, Covid-19, K-Means, P-Median

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