Algorithms to solve security games, an important class of Stackelberg games, have seen successful real-world deployment by LAX police and the Federal Air Marshal Service. These algorithms provide randomized schedules to optimally allocate limited security resources for infrastructure protection. Unfortunately, these stateof-the-art algorithms fail to scale-up or to provide a correct solution fo...

The present paper proposes a branch-and-price approach to the Traveling Umpire Problem (TUP). In this hard combinatorial optimization problem, umpires (or referees) have to be assigned to games in a double round robin tournament. The objective is to obtain a solution with minimum total travel distance over all umpires, while respecting several hard constraints. Dantzig-Wolfe decomposition is ap...

This paper presents an optimization to the flow patients for state health services offered to Parana State citizens and also analyzes a new optimized configuration for it. In Brazil, medical care is controlled by state officers, and is provided throughout a centralized planning managed by state governments in every one of Brazil’s 28 states. Since geographical area is a key factor in most state...

Branch-and-price algorithms for the graph coloring problem use an exponentially-sized independent set based integer programming formulation to produce usually tight lower bounds to enable more aggressive pruning in the branch-and-bound tree. One major problem inherent to any branch-and-price scheme for graph coloring is that in order to avoid destroying the pricing problem structure during colu...

This thesis describes a stochastic ship routing problem with inventory management. The problem involves finding a set of least costs routes for a fleet of ships transporting a single commodity when the demand for the commodity is uncertain. Storage at consumption and supply ports is limited and inventory levels are monitored in the model. Consumer demands are at a constant rate within each time...

The bin packing problem with conflicts consists in packing items in a minimum number of bins of limited capacity while avoiding joint assignments of items that are in conflict. Our study demonstrates the comparatively good performance of a generic Branch-and-Price algorithm for this problem. We made use of our black-box solver BaPCod, relying on its generic branching scheme and primal heuristic...

We are given a rectangle R in the plane and a nite set P of n points in the interior of R. A rectangular partition of R is a partition of the surface of R into smaller rectangles. A rectangular partition is said to be feasible with respect to P if no points in P lie in the strict interior of any rectangle of the partition. The length of a rectangular partition is computed as the sum of the leng...

This paper proposes a model and algorithm for optimizing staffing and shift scheduling decisions at a 24/7 cybersecurity operations center. We study a two-stage stochastic shift scheduling problem over a 14-day pay period with three shifts per day, several staffing and scheduling constraints, uncertain workloads and on call staffing options. We solve this problem with a heuristic simplification...

Abstract: Offering customers product flexibility is one strategy deployed by companies to build competitive advantage and defend profit margins. This strategy is particularly well-suited for products with a high degree of component modularity. The hard-disk drive is one such product. However, such strategies often complicate downstream activities such as production planning. In this presentatio...