Yazar "Birgören, Burak" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • [ X ]
    Öğe
    A Stochastic Bilevel Programming Model for an Industrial Symbiosis Network
    (Springer Science and Business Media Deutschland GmbH, 2024) Daş, G. Sena; Yeşilkaya, Murat; Altinkaynak, Büşra; Birgören, Burak
    A stochastic bilevel model for an industrial symbiosis (IS) network in an eco-industrial park (EIP) is presented in this paper. Companies in IS networks produce final products using mostly by-products rather than raw materials. Companies in these networks are known to share a variety of synergies, including wastes and by-products. They mostly negotiate on the price and amount of the by-products. This negotiation is critical as by-products should be available on time at the right amount for smooth production. Moreover, the use of these by-products should provide savings compared to the use of raw materials so that companies could benefit from IS. However, the fluctuations in the final product demand affect both the EIP management (the leader) and companies (followers) in the network. Therefore, we proposed a stochastic bilevel model where the lower-level problem is a two-stage stochastic programming model. Our findings show that the demand uncertainty has an impact on both parties. © 2024, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
  • [ X ]
    Öğe
    Comparison of Fuzzy Solution Approaches for a Bilevel Linear Programming Problem
    (Springer Science and Business Media Deutschland GmbH, 2023) Altınkaynak, Büşra; Göçken, Tolunay; Yeşilkaya, Murat; Birgören, Burak; Daş, Gülesin Sena
    In this study, we consider solution approaches used to solve the proposed bilevel linear programming model for an Industrial Symbiosis network. We first solve this model with the well-known Karush-Kuch-Tucker (KKT) approach. However, transforming a bilevel programming model with the KKT approach increases the number of variables and constraints. For this reason, we use the fuzzy programming approach and the fuzzy goal programming approaches as alternatives to the KKT approach. Next, we compare the results of the KKT approach with these methods and examine the suitability of these approaches to solve our bilevel problem. Unlike previous studies, which claimed that fuzzy approaches mostly outperform the KKT approach, in our case, the best solution is obtained with the KKT approach. This is most probably because these approaches ignore the hierarchical nature of the problem. We believe that more research on fuzzy approaches is needed to evaluate the suitability of these approaches for solving bilevel programming problems. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.