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Integer Linear Programming applied to determining monic hyperbolic irreducible polynomials with integer coefficients and span less than 4

Souad El Otmani, Armand Maul, Georges Rhin, Jean-Marc Sac-Épée (2013)

Journal de Théorie des Nombres de Bordeaux

In this work, we propose a new method to find monic irreducible polynomials with integer coefficients, only real roots, and span less than 4. The main idea is to reduce the search of such polynomials to the solution of Integer Linear Programming problems. In this frame, the coefficients of the polynomials we are looking for are the integer unknowns. We give inequality constraints specified by the properties that the polynomials should have, such as the typical distribution of their roots. These...

Integer programming approaches for minimum stabbing problems

Breno Piva, Cid C. de Souza, Yuri Frota, Luidi Simonetti (2014)

RAIRO - Operations Research - Recherche Opérationnelle

The problem of finding structures with minimum stabbing number has received considerable attention from researchers. Particularly, [10] study the minimum stabbing number of perfect matchings (mspm), spanning trees (msst) and triangulations (mstr) associated to set of points in the plane. The complexity of the mstr remains open whilst the other two are known to be 𝓝𝓟-hard. This paper presents integer programming (ip) formulations for these three problems, that allowed us to...

Large neighborhood improvements for solving car sequencing problems

Bertrand Estellon, Frédéric Gardi, Karim Nouioua (2006)

RAIRO - Operations Research - Recherche Opérationnelle

The 𝒩 P -hard problem of car sequencing has received a lot of attention these last years. Whereas a direct approach based on integer programming or constraint programming is generally fruitless when the number of vehicles to sequence exceeds the hundred, several heuristics have shown their efficiency. In this paper, very large-scale neighborhood improvement techniques based on integer programming and linear assignment are presented for solving car sequencing problems. The effectiveness of this approach...

Large neighborhood improvements for solving car sequencing problems

Bertrand Estellon, Frédéric Gardi, Karim Nouioua (2007)

RAIRO - Operations Research

The NP-hard problem of car sequencing has received a lot of attention these last years. Whereas a direct approach based on integer programming or constraint programming is generally fruitless when the number of vehicles to sequence exceeds the hundred, several heuristics have shown their efficiency. In this paper, very large-scale neighborhood improvement techniques based on integer programming and linear assignment are presented for solving car sequencing problems. The effectiveness of this approach...

Mathematical Optimization for the Train Timetabling Problem

Stanojević, Predrag, Marić, Miroslav, Kratica, Jozef, Bojović, Nebojša, Milenković, Miloš (2010)

Mathematica Balkanica New Series

AMS Subj. Classification: 90C57; 90C10;Rail transportation is very rich in terms of problems that can be modelled and solved using mathematical optimization techniques. The train scheduling problem as the most important part of a rail operating policy has a very significant impact on a rail company profit considering the fact that from the quality of a train timetable depends a flow of three most important resources on rail network: cars, locomotives and crews. The train timetabling problem aims at...

Métodos duales y algoritmos híbridos para problemas de "set partitioning".

Jaime Barceló Bugeda, Elena Fernández Areizaga (1990)

Trabajos de Investigación Operativa

En este artículo estudiamos la utilización de métodos duales en el diseño de algoritmos híbridos para la resolución de problemas de "Set Partitioning" (SP). Las técnicas duales resultan de gran interés para resolver problemas con estructura combinatoria no sólo porque generan cotas inferiores sino porque, además, su utilización junto con heurísticas y procedimientos de generación de desigualdades en el diseño de algoritmos híbridos permite evaluar la calidad de las cotas superiores obtenidas. Los...

Modelling integer linear programs with petri nets*

P. Richard (2010)

RAIRO - Operations Research

We show in this paper that timed Petri nets, with one resource shared by all the transitions, are directly connected to the modelling of integer linear programs (ILP). To an ILP can be automatically associated an equivalent Petri net. The optimal reachability delay is an optimal solution of the ILP. We show next that a net can model any ILP. I order to do this, we give a new sufficient reachability condition for the marking equation, which also holds for general Petri nets without timed transitions. ...

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