Tarım-Gıda Tedarik Zincirinde Ağ Tasarımı ve Optimizasyonu: Bir Meyve Suyu İşletmesi ÖrneğiBelkız Torğul, Enes Demiralay, Turan Paksoy
Tarımsal gıdalara ulaşamamak günümüzde yaygınlaşmaya başlayan büyük bir sorun haline gelmiştir. Tarımsal gıda tedarik zincirleri, gıda güvenliği ve halk sağlığı ile ilgili sorunlar nedeniyle son yıllarda tüketiciler, firmalar, devlet kurumları ve araştırmacıların daha fazla ilgisini çekmektedir. İnsanların yaşamını sağlıklı bir şekilde devam ettirebilmesi için en önemli ihtiyacı olan tarımsal gıdaların tedarik süreci çerçevesinde son yıllarda tüm dünyanın ilgisini çeken sürdürülebilirlik konusuna da yer verilmelidir. Bir tarımsal gıda tedarik zincirinin sürdürülebilirliğini etkileyen en kritik faktörlerden biri ağ tasarımıdır. Bu yüzden, tarımsal tedarik zincirlerinin tasarımı ve işletilmesi daha sıkı düzenlemelere tabi olmalıdır. Bu çalışmada, gıda tedarik zincirlerinin tasarımı için öncelikle operasyonel araştırma yöntemlerinin bir literatür incelemesi verilmiş ardından şeftali suyu ürünlerinin tedarik zinciri sürdürülebilirliği için yeni bir kapalı döngü ağ tasarımı uygulaması sunulmuştur. Şeftali suyu tedarik zinciri ağ tasarım modeli, karma tamsayılı doğrusal programlamaya dayalı olarak kârı maksimize etmek üzere formüle edilmiş ve sayısal bir örnek yardımıyla GAMS programında çözülerek doğrulanmıştır. Önerilen model, çiftçi-tedarikçi seçimi, taşıma ve dağıtım sorunlarını ele alırken geri dönüşüm süreci ile maliyet düşürme, çevrenin korunması ve atıkların ekonomiye kazandırılması faaliyetlerini ön plana çıkarmaktadır. Modelin çözüm sonuçları, ele alınan gıda- tedarik zincirinde en fazla mali giderlerin satın alma kalemi olduğunu ortaya koymuştur. Yapılan duyarlılık analizi ile çiftçilerden yeterli arz sağlanması yoluyla daha kısa tedarik zinciri oluşturmanın işletmeye hem ekonomik hem de çevresel olarak katkı sağlayacağı sonucuna varılmıştır.
Network Design and Optimization in Agri-Food Supply Chain: Application to A Juice BusinesssBelkız Torğul, Enes Demiralay, Turan Paksoy
Lack of access to agriculture-based food has become a major problem that is becoming increasingly widespread. Agri-food supply chains have attracted growing attention from consumers, companies, government agencies, and researchers in recent years due to problems with food safety and related public health issues. Sustainability, which has attracted global attention in recent years, should also be included within the optimal framework of the process of supplying agricultural food, which is among the most important needs people face in order to live healthy lives. One of the most critical factors affecting the agri-food supply chain’s sustainability is network design. Therefore, the design and operation of agri-food supply chains should be subject to stricter regulations. In this study, we conduct a literature review of operational research methods used in the design of agricultural food supply chains, and present a new, closed-loop network design application for supply chain sustainability of peach juice products. The peach juice supply chain network design model was formulated using linear programming to maximize profit and was verified using the GAMS program with the help of a numerical example. The proposed model framework highlights cost reduction activities within the recycling process, protecting the environment, and recovery the waste to the economy while addressing farmer‒supplier selection, transportation, and distribution problems.
Globalization and an increase in exports are playing a progressively important role in expanding supply chains (SCs) over wide areas. In addition, Supply Chain Management (SCM) has been gaining strategic importance in terms of its impact on the success of companies that have become business partners and/or competitors across different geographic areas. Suppliers, production facilities, distribution facilities, storage facilities, and collection and recovery facilities are members of the SC, and SCs are dynamic processes involving a continuous flow of materials, funds, and information within and between these members across multiple functional areas. SCM determines and oversees the number of entities, locations, capacities, and flows between SC members. The dynamics of SCM have changed over the years, as new paradigms have developed in order to respond to increasing environmental concerns and customer pressures. Lack of access to agricultural food has become a major problem. Agri-food SCs are attracting more attention from consumers, companies, government agencies, and researchers due to problems with food safety and related public health concerns. Sustainability, which has attracted global attention in recent years, should also be included within the framework of supplying agricultural food, which is the most important need for people to live healthy lives. Increasing environmental concerns, the impacts of climate change, social-environmental awareness, legal regulations of governments, declining resources and profit margins have increased the need and importance of sustainability. By collecting used products from end-users as part of the supply process, SCs have become cyclical and sustainable structures. Based on this transformed structure, the concept of “Closed-Loop SCM” (CLSC) or “Sustainable SCM” has emerged. One of the most critical factors affecting agri-food supply chain sustainability is network design. Therefore, we propose that the design and operation of agri-food supply chains, including network design, should be subject to stricter regulations.In this study, we first provide a literature review of operational research methods regarding the design of agricultural food SCs. Then, we present a new closed-loop network design application for a sustainable supply chain for peach juice products. In the processed peach products supply chain farmers are the main suppliers of raw materials. In addition to buying from farmers, producers sometimes obtain raw materials from large traders (second-tier suppliers). In these cases, the supply chain is extended as raw materials are not purchased directly from the farmers. Distributors distribute peach juice from the manufacturer to retailers or consumers, but retailers are the preferred distribution channel for manufacturers in marketing their peach juice products, as peach juice consumers consist of local consumers living in various regions. The manufacturer processes the peaches, which are procured from farmers or second-tier suppliers in June, July, and August, in their production center. Peach juice is delivered to the distribution and collection center, and from there it is forwarded to retailers, who are the customers. The company works in cooperation with the glass bottle supplier and packaging facilities to package their final products. In addition, it produces their products in accordance with environment friendly, sustainable agriculture food sector practices by selling the pulp produced during the production phase to be turned into organic fertilizer, and by collecting at least some of the used glass bottles from customers. The collected glass bottles that are suitable are then disinfected and reused in the production center, and the others are sold to a recycling center and then to the glass bottle supplier for reprocessing.The model developed to analyze the problem of optimizing the agri-food supply chain network design was formulated based on mixed integer linear programming with the objective function of maximizing profit, and was verified by solving it in the GAMS program using a numerical example. The model framework presented in this study highlights the cost reduction activities within the recycling process, protecting the environment, and recovering the manufacturing waste into the economy while addressing farmer‒supplier selection, transportation, and distribution problems. It also provides examples of how to overcome problems that often arise in agri-food systems, offering guidance to practitioners on key issues to be included in network design of agri-food supply chains. This peach juice production process implementation study serves as an example for presenting these modeling and optimization strategies and can be applied to a wide variety of agri-food SCs with similar characteristics.