SDP vs. LP relaxations for the moment approach in some performance evaluation problems

Given a Markov process we are interested in the numerical computation of the moments of the exit time from a bounded domain. We use a moment approach which, together with appropriate semidefinite positivity moment conditions, yields a sequence of semidefinite programs (or SDP relaxations), depending on the number of moments considered, that provide a sequence … Read more

Routing and wavelength assignment by partition coloring

We show in this work how the problem of routing and wavelength assignment in all-optical networks may be solved by a combined approach involving the computation of alternative routes for the lightpaths, followed by the solution of a partition coloring problem in a conflict graph. A new tabu search heuristic is also proposed for the … Read more

Solving diameter constrained minimum spanning tree problems in dense graphs

In this study, a lifting procedure is applied to some existing formulations of the Diameter Constrained Minimum Spanning Tree Problem. This problem typically models network design applications where all vertices must communicate with each other at minimum cost, while meeting or surpassing a given quality requirement. An alternative formulation is also proposed for instances of … Read more

Heuristics for the mirrored traveling tournament problem

Professional sports leagues are a major economic activity around the world. Teams and leagues do not want to waste their investments in players and structure in consequence of poor schedules of games.Game scheduling is a difficult task, involving several decision makers, different types of constraints, and multiple objectives to optimize. The Traveling Tournament Problem abstracts … Read more

A hybrid bin-packing heuristic to multiprocessor scheduling

The multiprocessor scheduling problem consists in scheduling a set of tasks with known processing times into a set of identical processors so as to minimize their makespan, i.e., the maximum processing time over all processors. We propose a new heuristic for solving the multiprocessor scheduling problem, based on a hybrid heuristic to the bin packing … Read more

Solving Nonlinear Portfolio Optimization Problems with the Primal-Dual Interior Point Method

Stochastic programming is recognized as a powerful tool to help decision making under uncertainty in financial planning. The deterministic equivalent formulations of these stochastic programs have huge dimensions even for moderate numbers of assets, time stages and scenarios per time stage. So far models treated by mathematical programming approaches have been limited to simple linear … Read more

An annotated bibliography of GRASP

This paper presents an annotated bibliography of greedy randomized adaptive search procedures (GRASP). The bibliography is current up to early 2004. The bibliography contains: background material; tutorials and surveys; enhancements to the basic method; hybrid methods; software; parallel GRASP; graph theory; quadratic and other assignment problems; location, layout, and cutting; covering, clustering, packing, and partitioning; … Read more

Optimal Pricing Policies for Perishable Products

In many industrial settings, managers face the problem of establishing a pricing policy that maximizes the revenue from selling a given inventory of items by a fixed deadline, with the full inventory of items being available for sale from the beginning of the selling period. This problem arises in a variety of industries, including the … Read more

Conditional Risk Mappings

We introduce an axiomatic definition of a conditional convex risk mapping and we derive its properties. In particular, we prove a representation theorem for conditional risk mappings in terms of conditional expectations. We also develop dynamic programming relations for multistage optimization problems involving conditional risk mappings. Citation Preprint Article Download View Conditional Risk Mappings