This paper approaches the integrated lot sizing and scheduling problem (ILSSP), in which non-identical machines work parallel with non-triangular sequence-dependent setup costs times, carry-over capacity limitation. The aim of studied ILSSP, here called ILSSP-NT on machines, is to determine a production planning tasks sequencing that meet period demands without delay such way total production, ...

In this paper, we address an optimization problem resulting from the combination of the wellknown traveling salesman and knapsack problems. In particular, we target the orienteering problem, originated in the context of sports, which consists of maximizing the total score associated with the vertices visited in a path within the available time. The problem, also known as the selective travellin...

In this paper, we develop a greedy randomized adaptive search procedure (GRASP) for the problem of minimizing straight-line crossings in a 2-layer graph. The procedure is fast and is particularly appealing when dealing with low-density graphs. When a modest increase in computational time is allowed, the procedure may be coupled with a path relinking strategy to search for improved outcomes. Alt...

Joseph M. PASIA Xavier GANDIBLEUX Karl F. DOERNER Richard F. HARTL Department of Mathematics Laborataire d‘ Informatique de Nantes Atlantique Department of Management Science Department of Management Science University of the Philippines-Diliman Université de Nantes University of Vienna University of Vienna Quezon City, PHILIPPINES Nantes, FRANCE Vienna, AUSTRIA Vienna, AUSTRIA [email protected]...

A frame relay service offers virtual private networks to customers by provisioning a set of long-term private virtual circuits (PVCs) between customer endpoints on a large backbone network. During the provisioning of a PVC, routing decisions are made without any knowledge of future requests. Over time, these decisions can cause inefficiencies in the network and occasional offline rerouting of t...

Scatter search (SS) is a population-based method that has recently been shown to yield promising outcomes for solving combinatorial and nonlinear optimization problems. Based on formulations originally proposed in the 1960s for combining decision rules and problem constraints, SS uses strategies for combining solution vectors that have proved effective in a variety of problem settings. Path rel...

The materialization of views promotes the reduction of multidimensional queries’s execution time. However, this materialization has an associated cost that may exceed the cost constraints of a given environment, characterizing the view selection problem (VSP). VSP consists in selecting the best views given a certain cost threshold. Several solutions have been proposed in the literature to try a...

The equitable dispersion problem consists in selecting a subset of elements from a given set in such a way that a measure of dispersion is maximized. In particular, we target the max-mean dispersion model in which the average distance between the selected elements is maximized. We first review previous methods and mathematical formulations for this and related dispersion problems and then propo...