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The capacitated edge activation problem consists of activating a minimum cost set of capacitated edges to ensure the routing of some traffic demands. If the demands are subject to uncertainty, we speak of the robust capacitated edge activation problem. We consider a capacity formulation of the problem and investigate, from a polyhedral perspective, the similarities and the differences between the robust capacitated edge activation and the robust network loading polyhedron, as well as between the polyhedra corresponding to different routing and flows policies. [ABSTRACT FROM AUTHOR]

In this paper we study a network design problem arising in the management of a carrier network. The aim is to route a traffic matrix, minimizing a measure of the network congestion while guaranteeing a prescribed quality of service. We formulate the problem, devise presolve procedures to reduce the size of the corresponding mixed‐integer programming formulation and show that the proposed approach can efficiently solve some real‐life problems, leading to an improvement with respect to the current practice in a real case study. [ABSTRACT FROM AUTHOR]

Given a capacitated network, the Capacitated Edge Activation problem consists of choosing the edges to be activated to ensure the routing of a set of demands. We focus on capacity formulations of the problem, that is, formulations including only design variables, whereas variables corresponding to the routes are projected out. First, we investigate the combinatorial properties of the problem to derive a capacity formulation both for splittable flows (the routes are unrestricted) and for unsplittable ones (each demand must be routed on a single path). Then, we study the corresponding polyhedron, identifying valid and facet‐defining inequalities. Finally, we develop a branch‐and‐cut algorithm and present computational results. [ABSTRACT FROM AUTHOR]

This article focuses on the problem of minimizing the energy consumption in a resilient telecommunications network. For each demand, an edge-disjoint pair of paths (primary and backup) must be provided and the shared protection scheme is used. The energy consumption is due only to edges used in the no-fault scenario, but both primary and backup paths contribute to capacity consumption. We propose a projected formulation for the problem and show its effectiveness by comparing it with the complete formulation. We propose valid inequalities for both formulations. We evaluate the performances of the proposed formulations and valid inequalities through computational tests. Furthermore, we investigate the relationship between the shared and the dedicated protection version of the problem. © 2016 Wiley Periodicals, Inc. NETWORKS, Vol. 69(1), 6-22 2017 [ABSTRACT FROM AUTHOR]

We consider an energy-aware network management problem with shared protection. Energy consumption is due to the devices that are active in the nominal scenario. We propose a complete formulation and a projected one (which uses only primary path variables) and we compare their computational performances. [ABSTRACT FROM AUTHOR]

We consider the robust network design problem, which consists of choosing capacities for the edges of a graph so that a set of uncertain traffic demands can be routed. The scope of the paper is to study the robust cut property (RCP), that is, we investigate when the cut inequalities are sufficient to guarantee a feasible routing under demand uncertainty. We provide conditions that ensure the RCP. We discuss the generalization to the problem with uncertain demands of the results that are known for the problem without uncertainty. © 2015 Wiley Periodicals, Inc.NETWORKS, Vol. 66(2), 159-168 2015 [ABSTRACT FROM AUTHOR]

Different approaches have been proposed in the literature to handle uncertain parameters in health care optimisation problems. Among them, the cardinality-constrained approach to robust optimisation seems suitable for handling several of these problems because it allows a trade-off between the level of robustness and the cost of the solution, and an easy implementation that can be understood by clinicians and planners without any background in operations research. Thus far, however, cardinality-constrained approach has rarely been applied to health care. We recently applied the cardinality-constrained approach to two relevant health care management problems, namely, the operating room planning problem and the nurse-to-patient assignment problem in home care services. In this communication, we briefly describe our experience and focus on general considerations, advantages, and remarks that can help operations researchers in evaluating the approach for other applications in health care management. [ABSTRACT FROM AUTHOR]

A multilayer network is a hierarchical network where each layer is built using the components of the previous one. Optical networks are an example of two layered networks. The multilayer network design problem consists of installing minimum cost integer capacities on the edges of all the layers so that a set of demands can be routed on the network. In this article, two versions of the optical network design problem are studied, and polyhedral results for the corresponding capacity formulations are presented. We also show how to extend the results to a network with an arbitrary number of layers. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2013 [ABSTRACT FROM AUTHOR]

Abstract: We consider the Robust Network Design problem, i.e. the problem of dimensioning the capacities on the edges of a graph to serve point-to-point traffic demands subject to uncertainty. The scope of the paper is to investigate when the cut condition is sufficient to guarantee the feasibility for such problem. [Copyright &y& Elsevier]