We address a multi-item capacitated lot-sizing problem with setup times and shortage costs that arises in real-world production planning problems. Demand cannot be backlogged, but can be totally or partially lost. The problem is NP-hard. A mixed integer mathematical formulation is presented. Our approach in this paper is to propose some classes of valid inequalities based on a generalization of...

We propose a branch-and-cut algorithm for the Maximum Cardinality Stable Set problem. Rank constraints of general structure are generated by executing clique separation algorithms on a modi4ed graph obtained with edge projections. A branching scheme exploiting the available inequalities is also introduced. A computational experience on the DIMACS benchmark graphs validates the e8ectiveness of t...

In this contribution we address the implications of Bekenstein Criterion in branch-cut cosmology. The impossibility packaging energy and entropy according to a finite size makes transition phase cosmology very peculiar, imposing topological leap between contraction expansion phases primordial universe or region similar wormhole, with space-time shaping itself topologically format helix-format a...

This paper proposes a tractable model for the design of a rapid transit system. Travel cost is minimized and traffic capture is maximized. The problem is modeled on an undirected graph and cast as an integer linear program. The idea is to build segments within broad corridors to connect some vertex sets. These segments can then be assembled into lines, at a later stage. The model is solved by b...

Mixed-integer nonlinear optimization problems arise in scientific and operational applications ranging from the reordering of nuclear fuel rods to the design of wireless networks. We present some novel mixed-integer nonlinear optimization applications and review existing solution techniques. We also describe some experiments with nonlinear branch-and-bound branching techniques that lead us to p...

The purpose of this paper is to illustrate a general framework for network location problems, based on column generation and branch-andprice. In particular we consider capacitated network location problems with single-source constraints. We consider several different network location models, by combining cardinality constraints, fixed set-up costs, concentrator restrictions and regional constra...

This paper presents some strong valid inequalities for the Maximum Common Induced Subgraph Problem (MCIS) and the proofs that the inequalities are facet-defining under certain conditions. TheMCIS is an NP-hard problem and, therefore, no polynomial time algorithm is known to solve it. In this context, the study of its polytope can help in the development of more efficient branch-and-bound and br...