Benders Decomposition for Very Large Scale Partial Set Covering and Maximal Covering Problems

Covering problems constitute an important family of facility location problems. This paper intro- duces a new exact algorithm for two important members of this family: i) the maximal covering location problem, which requires finding a subset of facilities that maximizes the amount of demand covered while respecting a budget constraint on the cost of the … Read more

Lower bounds on the lattice-free rank for packing and covering integer programs

In this paper, we present lower bounds on the rank of the split closure, the multi-branch closure and the lattice-free closure for packing sets as a function of the integrality gap. We also provide a similar lower bound on the split rank of covering polyhedra. These results indicate that whenever the integrality gap is high, … Read more

Aggregation-based cutting-planes for packing and covering integer programs

In this paper, we study the strength of Chvatal-Gomory (CG) cuts and more generally aggregation cuts for packing and covering integer programs (IPs). Aggregation cuts are obtained as follows: Given an IP formulation, we first generate a single implied inequality using aggregation of the original constraints, then obtain the integer hull of the set defined … Read more

Coverings and Matchings in r-Partite Hypergraphs

Ryser’s conjecture postulates that, for $r$-partite hypergraphs, $\tau \leq (r-1) \nu$ where $\tau$ is the covering number of the hypergraph and $\nu$ is the matching number. Although this conjecture has been open since the 1960s, researchers have resolved it for special cases such as for intersecting hypergraphs where $r \leq 5$. In this paper, we … Read more