We extend the Sherali-Adams, Lovász-Schrijver, Balas-Ceria-Cornuéjols and Lasserre lift-and-project methods for 0-1 optimization by considering liftings to subset algebras. Our methods yield polynomialtime algorithms for solving a relaxation of a set-covering problem at least as strong as that given by the set of all valid inequalities with small coefficients, and, more generally, all valid ine...

The cutting-plane approach to integer programming was initiated more that 40 years ago: Gomory introduced the corner polyhedron as a relaxation of a mixed integer set in tableau form and Balas introduced intersection cuts for the corner polyhedron. This line of research was left dormant for several decades until relatively recently, when a paper of Andersen, Louveaux, Weismantel and Wolsey gene...

This article investigates cutting planes for mixed-integer disjunctive programs. In the early 1980s, Balas and Jeroslow presented monoidal disjunctive cuts exploiting the integrality of variables. For disjunctions arising from binary variables, it is known that these cutting planes are essentially the same as Gomory mixed-integer and mixed-integer rounding cuts. In this article, we investigate ...

We investigate a structural decomposition for the capacitated vehicle routing problem (CVRP) based on vehicle-to-customer “assignment” and visits “sequencing” decision variables. We show that an heuristic search focused on assignment decisions with a systematic optimal choice of sequences (using Concorde TSP solver) during each move evaluation is promising but requires a prohibitive computation...

We consider a formalization of the following problem. A salesperson must sell some quota of brushes in order to win a trip to Hawaii. This salesperson has a map (a weighted graph) in which each city has an attached demand specifying the number of brushes that can be sold in that city. What is the best route to take to sell the quota while traveling the least distance possible? Notice that unlik...

El presente artículo explora de forma panorámica las representaciones literarias sobre Emiliano Zapata durante la década los años treinta, período marcado por articulación una memoria revolucionaria nacional, institucional y homogénea, en que el caudillo suriano desempeña esencial función encarnar aspiraciones del campesino. corpus está compuesto tres conjuntos: ficción, anécdotas textos testim...