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A Branch-and-Cut Algorithm for the Symmetric Generalized Traveling Salesman Problem
We consider a variant of the classical symmetric Traveling Salesman Problem in which the nodes are partitioned into clusters and the salesman has to visit at least one node for each cluster. This
Solving the Orienteering Problem through Branch-and-Cut
A branch-and-cut algorithm for finding an optimal OP solution, based on several families of valid inequalities, is described and proved to be able to solve to optimality large-scale instances involving up to 500 nodes, within acceptable computing time.
An Exact Approach for the Vehicle Routing Problem with Two-Dimensional Loading Constraints
An exact approach is proposed, based on a branch-and-cut algorithm, for the minimization of the routing cost that iteratively calls a branch and-bound algorithm for checking the feasibility of the loadings.
The Capacitated m-Ring-Star Problem
Two integer programming formulations for the Capacitated m-Ring-Star Problem are presented and valid inequalities are proposed to strengthen the linear programming relaxation and are used as cutting planes in a branch-and-cut approach.
The Ring Star Problem: Polyhedral analysis and exact algorithm
This article formulates the Ring Star Problem as a mixed-integer linear program and strengthens it with the introduction of several families of valid inequalities that are shown to be facet-defining and are used to develop a branch-and-cut algorithm.
Solving the Cell Suppression Problem on Tabular Data with Linear Constraints
This paper addresses the problem of protecting sensitive data in a statistical table whose entries are linked by a generic system of linear constraints, and introduces a new integer linear programming model and outline an enumerative algorithm for its exact solution.
Exact algorithms for the job sequencing and tool switching problem
Two integer linear programming formulations for the job Sequencing and tool Switching Problem are proposed and compared and results indicate that instances involving up to 25 jobs can be solved optimally using the branch-and-bound approach.
Heuristics for the One-Commodity Pickup-and-Delivery Traveling Salesman Problem
Two heuristic approaches are proposed for the well-knowntraveling salesman problem in which cities correspond to customers providing or requiring known amounts of a product, and the vehicle has a given upper limit capacity.
Projection results for vehicle routing
A survey of formulations for the capacitated VRP, and various results of a similar flavour to those of Gouveia are presented, which show that the three-index formulation, augmented by certain families of valid inequalities, gives the same lower bound as the two- Index formulation, and the set partitioning formulation implies by projection both multistar and hypotour-like inequalities in theTwo-index space.