Lagrangian Relaxation Method for the Step fixed-charge Transportation Problem
Subject Areas : Statisticsعلی محمودیراد 1 , صادق نیرومند 2 , مسعود صانعی 3 , عبدالرحمان ساجدی نژاد 4
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Abstract :
In this paper, a step fixed charge transportation problem is developed where the products are sent from the sources to the destinations in existence of both unit and step fixed-charges. The proposed model determines the amount of products in the existing routes with the aim of minimizing the total cost (sum of unit and step fixed-charges) to satisfy the demand of each customer. As the problem is NP-hard, a moderate sized instance of this problem becomes intractable for general-purpose solvers. In order to overcome this difficulty, a Lagrangian relaxation approach is proposed. The computational experiments show that the Lagrangian relaxation algorithm isable to solve large sized problems with optimality gap compared togeneral-purpose solvers.
