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    Öğe
    A mathematical programming model for facility location optimization of hydrogen production from renewable energy sources
    (Taylor & Francis Inc, 2022) Derse, Onur; Gocmen, Elifcan; Yilmaz, Ebru; Erol, Rizvan
    Fossil fuels are the primary energy sources and meet the global energy demands. However, environmental and health problems related with these sources boosted the demand for renewable energy sources. Hydrogen, as an energy carrier has a growing potential for solving these problems. In this article, a mathematical programming model that integrates the production, storage and transportation, safety, location, and staff assignment decisions is presented considering minimization of costs. Although most of the studies focus on location, distribution, storage decisions of hydrogen energy networks, the article also includes production, safety and staff assignment decisions to make this problem more practical. Furthermore, we also investigate the set covering constraint will ensure that each region is covered by minimum number of the hydrogen facilities. The developed model ensures a balance between location, distribution, storage, production, safety and staff decisions by installing two production facilities by assigning total 9 warehouses, 22 tank trucks, 12100 km pipeline, 35 staffs under distance constraint 2000 km in regions 1 and 5. The computational results indicate that the proposed model produces effective solutions for the coverage to all region and minimum total cost for real-case situations.
  • [ X ]
    Öğe
    Transportation mode choice using fault tree analysis and mathematical modeling approach
    (Taylor & Francis Inc, 2021) Derse, Onur; Gocmen, Elifcan
    In this paper, transportation problem of hazardous materials (hazmat) by various transportation modes is considered. Accident probabilities related to human and ecologic risks are assumed for each transportation mode including road, rail, and marine modes. Thus, a two-stage approach following the fault tree analysis (FTA) first, a mathematical modeling approach second is provided. In the first stage, FTA is employed to analyze the risks for each transportation mode. In the second stage, a mixed integer nonlinear programing model is formulated by using the results of the FTA to minimize the transportation cost and risk cost for each mode. Computational results for the instances in the literature and generated instances are provided. Results show that the two-stage approach is able to produce high-quality solutions. Most effective parameter is human-based possibility with 82% for the road accident, vehicle-based possibility with 64% for the rail accident, material-based possibility with 76% for the marine accident during the hazmat transportation.