A Branch-and-Price Algorithm for Fast and Equitable Last-Mile Relief Aid Distribution

This paper presents a novel approach to optimizing relief aid distribution in post-disaster scenarios. The core contribution lies in the development of a branch-and-price algorithm that addresses both efficiency (minimizing travel time) and equity (minimizing inequity in unmet demand). The use of a bi-objective optimization framework, combined with valid inequalities and a tailored algorithm for optimal allocation, demonstrates a rigorous methodology. The empirical validation using real-world data from Turkey and predicted data for Istanbul strengthens the practical relevance of the research. The significant performance improvement over commercial MIP solvers highlights the algorithm's effectiveness. The finding that lexicographic optimization is effective under extreme time constraints provides valuable insights for practical implementation.

• •Branch-and-price algorithm effectively optimizes relief aid distribution.
• •Bi-objective approach balances efficiency and equity in aid delivery.
• •Algorithm outperforms commercial MIP solvers on realistic datasets.