4 papers · 1 filter
Learning to reoptimize: a GNN-aided fix-and-optimize approach and an application to the Lot Sizing problem
Mathieu Lerouge, Andrea Lodi, Enrico Malaguti +2
In many operational contexts, solutions to NP-hard combinatorial optimization problems, modeled by means of Mixed-Integer Linear Programming (MILP), may become infeasible due to un…
Enforcing TSP-Optimality in Fair Vehicle Routing by Cutting Planes
Bart van Rossum, Rui Chen, Andrea Lodi
We study the fair capacitated vehicle routing problem, in which a fleet of vehicles must serve a set of customers such that the difference between the longest and shortest route, t…
Learning Large Neighborhood Search for Maritime Inventory Routing Optimization
Rui Chen, Defeng Liu, Nan Jiang +3
Maritime inventory routing optimization is an important yet challenging combinatorial optimization problem. We propose a machine learning-based local search approach for finding fe…
Efficient Branching Rules for Optimizing Range and Order-Based Objective Functions
Bart van Rossum, Rui Chen, Andrea Lodi
We consider range minimization problems featuring exponentially many variables, as frequently arising in fairness-oriented or bi-objective optimization. While branch and price is s…