Time filter

Source Type

Montigny-lès-Metz, France

Paris S.,Lita Inc
Proceedings Elmar - International Symposium Electronics in Marine | Year: 2010

Image quality assessment (QA) mimics the user's ability in evaluating image distortion. The presented technique uses a wavelet analysis and a distance measure associated to it. As often noticed, the wavelet analysis is a good approximation of the human visual system (HVS). The main contribution of this paper is the definition of a wavelet-based euclidean distance which embeds both, the deep-structure of the images and the specific orientation of every subband. This new definition of distance allows for an effective QA almost parameterless.

Stratulat S.,Lita Inc
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2010

We give evidence of the direct integration and automated checking of implicit induction-based proofs inside certified reasoning environments, as that provided by the Coq proof assistant. This is the first step of a long term project focused on 1) mechanically certifying implicit induction proofs generated by automated provers like Spike, and 2) narrowing the gap between automated and interactive proof techniques inside proof assistants such that multiple induction steps can be executed completely automatically and mutual induction can be treated more conveniently. Contrary to the current approaches of reconstructing implicit induction proofs into scripts based on explicit induction tactics that integrate the usual proof assistants, our checking methodology is simpler and fits better for automation. The underlying implicit induction principles are separated and validated independently from the proof scripts that consist in a bunch of one-to-one translations of implicit induction proof steps. The translated steps can be checked independently, too, so the validation process fits well for parallelisation and for the management of large proof scripts. Moreover, our approach is more general; any kind of implicit induction proof can be considered because the limitations imposed by the proof reconstruction techniques no longer exist. An implementation that integrates automatic translators for generating fully checkable Coq scripts from Spike proofs is reported. © 2010 Springer-Verlag Berlin Heidelberg.

Manea F.,University of Bucharest | Margenstern M.,Lita Inc | Mitrana V.,University of Bucharest | Mitrana V.,Rovira i Virgili University | Perez-Jimenez M.J.,University of Seville
Theory of Computing Systems | Year: 2010

We consider three complexity classes defined on Accepting Hybrid Networks of Evolutionary Processors (AHNEP) and compare them with the classical complexity classes defined on the standard computing model of Turing machine. By definition, AHNEPs are deterministic. We prove that the classical complexity class NP equals the family of languages decided by AHNEPs in polynomial time. A language is in P if and only if it is decided by an AHNEP in polynomial time and space. We also show that PSPACE equals the family of languages decided by AHNEPs in polynomial length. © Springer Science+Business Media, LLC 2008.

Rebai M.,University of Technology of Troyes | Kacem I.,Lita Inc | Adjallah K.H.,Metz National School of Engineering
Journal of Intelligent Manufacturing | Year: 2012

In this paper, we consider the problem of scheduling a set of M preventive maintenance tasks to be performed on M machines. The machines are assigned to execute production tasks. We aim to minimize the total preventive maintenance cost such that the maintenance tasks have to continuously be run during the schedule horizon. Such a constraint holds when the maintenance resources are not sufficient. We solve the problem by two exact methods and meta-heuristic algorithms. As exact procedures we used linear programming and branch and bound methods. As meta-heuristics, we propose a local search approach as well as a genetic algorithm. Computational experiments are performed on randomly generated instances to show that the proposed methods produce appropriate solutions for the problem. The computational results show that the deviation of the meta-heuristics solutions to the optimal one is very small, which confirms the effectiveness of meta-heuristics as new approaches for solving hard scheduling problems. © 2010 Springer Science+Business Media, LLC.

Boudjeloud-Assala L.,Lita Inc
International Journal of Bio-Inspired Computation | Year: 2012

Usual visualisation techniques for multidimensional datasets, such as parallel coordinates and scatterplot matrices, do not scale well to high numbers of dimensions. A common approach to solve this problem is dimensionality selection. Existing dimensionality selection techniques usually select pertinent dimension subsets that are significant to the user without loose of information. We present concrete cooperation between automatic algorithms, interactive algorithms and visualisation tools: the evolutionary algorithm is used to obtain optimal dimension subsets which represent the original dataset without loosing information for unsupervised mode (clustering or outlier detection). The last effective cooperation is a visualisation tool used to present the user interactive evolutionary algorithm results and let him actively participate in evolutionary algorithm searching with more efficiency resulting in a faster evolutionary algorithm convergence. We have implemented our approach and applied it to real dataset to confirm this approach is effective for supporting the user in the exploration of high dimensional datasets. Copyright © 2012 Inderscience Enterprises Ltd.

Discover hidden collaborations