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Combining evolutionary algorithms and exact approaches for multi-objective knowledge discovery

Mohammed Khabzaoui, Clarisse Dhaenens, El-Ghazali Talbi (2008)

RAIRO - Operations Research

An important task of knowledge discovery deals with discovering association rules. This very general model has been widely studied and efficient algorithms have been proposed. But most of the time, only frequent rules are seeked. Here we propose to consider this problem as a multi-objective combinatorial optimization problem in order to be able to also find non frequent but interesting rules. As the search space may be very large, a discussion about different approaches is proposed and a hybrid...

Combining odometry and visual loop-closure detection for consistent topo-metrical mapping

S. Bazeille, D. Filliat (2010)

RAIRO - Operations Research - Recherche Opérationnelle

We address the problem of simultaneous localization and mapping (SLAM) by combining visual loop-closure detection with metrical information given by a robot odometry. The proposed algorithm extends a purely appearance-based loop-closure detection method based on bags of visual words [A. Angeli, D. Filliat, S. Doncieux and J.-A. Meyer, IEEE Transactions On Robotics, Special Issue on Visual SLAM 24 (2008) 1027–1037], which is able to detect when the robot has returned back to a previously visited...

Combining Odometry and Visual Loop-Closure Detection for Consistent Topo-Metrical Mapping

S. Bazeille, D. Filliat (2011)

RAIRO - Operations Research

We address the problem of simultaneous localization and mapping (SLAM) by combining visual loop-closure detection with metrical information given by a robot odometry. The proposed algorithm extends a purely appearance-based loop-closure detection method based on bags of visual words [A. Angeli, D. Filliat, S. Doncieux and J.-A. Meyer, IEEE Transactions On Robotics, Special Issue on Visual SLAM24 (2008) 1027–1037], which is able to detect when the robot has returned back to a previously visited...

Comparing classification tree structures: A special case of comparing q-ary relations II

I. C. Lerman, F. Rouxel (2010)

RAIRO - Operations Research

Comparing q-ary relations on a set 𝒪 of elementary objects is one of the most fundamental problems of classification and combinatorial data analysis. In this paper the specific comparison task that involves classification tree structures (binary or not) is considered in this context. Two mathematical representations are proposed. One is defined in terms of a weighted binary relation; the second uses a 4-ary relation. The most classical approaches to tree comparison are discussed in the context...

Comparing classification tree structures: a special case of comparing q-ary relations

Israel-Cesar Lerman (2010)

RAIRO - Operations Research

Comparing q-ary relations on a set 𝒪 of elementary objects is one of the most fundamental problems of classification and combinatorial data analysis. In this paper the specific comparison task that involves classification tree structures (binary or not) is considered in this context. Two mathematical representations are proposed. One is defined in terms of a weighted binary relation; the second uses a 4-ary relation. The most classical approaches to tree comparison are discussed in the context...

Comparing imperfection ratio and imperfection index for graph classes

Arie M. C. A. Koster, Annegret K. Wagler (2008)

RAIRO - Operations Research - Recherche Opérationnelle

Perfect graphs constitute a well-studied graph class with a rich structure, reflected by many characterizations with respect to different concepts. Perfect graphs are, for instance, precisely those graphs G where the stable set polytope STAB ( G ) coincides with the fractional stable set polytope QSTAB ( G ) . For all imperfect graphs G it holds that STAB ( G ) QSTAB ( G ) . It is, therefore, natural to use the difference between the two polytopes in order to decide how far an imperfect graph is away from being perfect. We discuss three...

Comparing Imperfection Ratio and Imperfection Index for Graph Classes

Arie M.C.A. Koster, Annegret K. Wagler (2009)

RAIRO - Operations Research

Perfect graphs constitute a well-studied graph class with a rich structure, reflected by many characterizations with respect to different concepts. Perfect graphs are, for instance, precisely those graphs G where the stable set polytope STAB(G) coincides with the fractional stable set polytope QSTAB(G). For all imperfect graphs G it holds that STAB(G) ⊂ QSTAB(G). It is, therefore, natural to use the difference between the two polytopes in order to decide how far an imperfect graph is away...

Currently displaying 721 – 740 of 2805