An ant colony optimization inspired algorithm for the set packing problem with application to railway infrastructure

http://www.emse.fr/~delorme/Papiers/MIC05/MIC05_resume.pdfInternational audienceThe paper concerns an Ant Colony Optimisation (ACO) procedure as approximation method for the railway infrastructure capacity (RIC) problem. Railway infrastructure managers now have to deal with operators' requests for increased capacity. Planning the construction or reconstruction of infrastructures must be done very carefully due to the huge required invest- ments and the long term implications. Usually, assessing the capacity of one component of a rail system is done by measuring the maximum number of trains that can be operated on this component within a certain time period. In our work, we deal with two real situations. The first is Pierrefitte-Gonnesse crossing point located at the north of Paris. The second is the Lille-Flandres station which is the largest station in North of France. Measuring the capacity of junctions is a matter of solving an optimisation problem called the saturation problem [1], and which can be formulated as a Set Packing Problem (SPP). Given a finite set I = {1, . . . , n} of items and {Tj}, j 2 J = {1, . . . ,m}, a collection of m subsets of I, a packing is a subset P I such that |Tj \ P| 1, 8j 2 J. The set J can be also seen as a set of exclusive con- straints between some items of I. Each item i 2 I has a positive weight denoted by ci and the aim of the SPP is to calculate the packing which maximises the total weight. This proble

Boosting Pixel-based Classifiers for Face Verification

The performance of face verification systems has steadily improved over the last few years. State-of-the-art methods use the projection of the gray-scale face image into a Linear Discriminant subspace as input of a classifier such as Support Vector Machines or Multi-layer Perceptrons. Unfortunately, these classifiers involve thousands of parameters that are difficult to store on a smart-card for instance. Recently, boosting algorithms has emerged to boost the performance of simple (weak) classifiers by combining them iteratively. The famous AdaBoost algorithm have been proposed for object detection and applied successfully to face detection. In this paper, we investigate the use of AdaBoost for face verification to boost weak classifiers based simply on pixel values. The proposed approach is tested on a benchmark database, namely XM2VTS. Results show that boosting only hundreds of classifiers achieved near state-of-the-art results. Furthermore, the proposed approach outperforms similar work on face verification using boosting algorithms on the same database

Chemical inhibition of NAT10 corrects defects of laminopathic cells.

Down-regulation and mutations of the nuclear-architecture proteins lamin A and C cause misshapen nuclei and altered chromatin organization associated with cancer and laminopathies, including the premature-aging disease Hutchinson-Gilford progeria syndrome (HGPS). Here, we identified the small molecule "Remodelin" that improved nuclear architecture, chromatin organization, and fitness of both human lamin A/C-depleted cells and HGPS-derived patient cells and decreased markers of DNA damage in these cells. Using a combination of chemical, cellular, and genetic approaches, we identified the acetyl-transferase protein NAT10 as the target of Remodelin that mediated nuclear shape rescue in laminopathic cells via microtubule reorganization. These findings provide insights into how NAT10 affects nuclear architecture and suggest alternative strategies for treating laminopathies and aging.We thank Imagif and Institut de Chimie des Substances Naturelles, centre de recherche CNRS de Gif-sur-Yvette, France, for proteomic analysis. Research in the Jackson laboratory is funded by Cancer Research UK program grant 11 C6/A11224, the European Research Council, and the European Community Seventh Framework Programme grant agreement no. HEALTH-F2-2010-259893 (DDR). Core funding is provided by CRUK (C6946/A14492) and the Wellcome Trust (WT092096). S.P.J. receives his salary from the University of Cambridge, UK, supplemented by CRUK. D.L is funded by an EMBO Long-term fellowship ALTF 834-2011 and by a Project Grant from the Medical Research Council, UK MR/L019116/1, S.B. was funded by an EMBO Long-Term fellowship ALTF 93-2010 and Cancer Research UK. R.R. is supported by the Centre National de la Recherche Scientifique. M.D. is supported by the European Research Council grant DDREAM.

Mass wasting processes along the Owen Ridge (Northwest Indian Ocean)

International audienceThe Owen Ridge is a prominent relief that runs parallel to the coast of Oman in the NW Indian Ocean and is closely linked to the Owen Fracture Zone, an 800-km- long active fault system that accommodates today the Arabia-India strike-slip motion. Several types of mass failures mobilizing the pelagic cover have been mapped in details along the ridge using multibeam bathymetry and sediment echosounder. Here we present a synthetic map of the different types of mass wasting features observed along the ridge and we further establish a morphometric analysis of submarine landslides. The spatial variation of failure morphology is strongly related to the topography of the basement. The highest volumes of multi-events generated slides are mobilized along the southern portion of the ridge. There, the estimated volume of evacuated material during a slide is up to 45 km3. Combining these new observations with re-interpreted ODP seismic lines (Leg 117) documents sporadic mass wasting events through time along the southern segment of the ridge since its uplift in the Early Miocene, with a typical recurrence rate of the order of 105-106 years. Although seismicity may still be the final triggering process, mass wasting frequency is mainly controlled by the slow pelagic sedimentation rates and hence, time needed to build up the 40-80 m thick pelagic cover required to return to a mechanically unstable pelagic cover

Exploiting the Reactivity of 1,2-Ketoamides: Enantioselective Syn-thesis of Functionalized Pyrrolidines and Pyrrolo-1,4-benzodiaze-pine-2,5-diones

International audienceA new strategy for the synthesis of optically active pyrrolo[ 1,4]benzo- diazepine-2,5-diones has been developed. The approach is based on an initial Michael addition of functionalized 1,2-ketoamides on nitroalkenes, with a reduction–double cyclization sequence leading to the desired substituted benzodiazepine

Methane storms as a driver of Titan's dune orientation

Titan's equatorial regions are covered by eastward propagating linear dunes. This direction is opposite to mean surface winds simulated by Global Climate Models (GCMs), which are oriented westward at these latitudes, similar to trade winds on Earth. Different hypotheses have been proposed to address this apparent contradiction, involving Saturn's gravitational tides, large scale topography or wind statistics, but none of them can explain a global eastward dune propagation in the equatorial band. Here we analyse the impact of equinoctial tropical methane storms developing in the superrotating atmosphere (i.e. the eastward winds at high altitude) on Titan's dune orientation. Using mesoscale simulations of convective methane clouds with a GCM wind profile featuring superrotation, we show that Titan's storms should produce fast eastward gust fronts above the surface. Such gusts dominate the aeolian transport, allowing dunes to extend eastward. This analysis therefore suggests a coupling between superrotation, tropical methane storms and dune formation on Titan. Furthermore, together with GCM predictions and analogies to some terrestrial dune fields, this work provides a general framework explaining several major features of Titan's dunes: linear shape, eastward propagation and poleward divergence, and implies an equatorial origin of Titan's dune sand.Comment: Published online on Nature Geoscience on 13 April 201

L’inhibition chimique de NAT10 corrige les défauts des cellules laminopathiques

La lamina nucléaire maintient l’architecture du noyau Chez les eucaryotes, la membrane interne du noyau est bordée d’un maillage de protéines fibrillaires appelé lamina nucléaire, composé des protéines dénommées lamines, incluant les lamines A et C [1]. La lamina nucléaire est un élément crucial du maintien de l’architecture et de la forme du noyau, ainsi que de l’organisation globale de la chromatine, car elle sert de plateforme d’ancrage pour l’hétérochromatine et pour les régions télomériques [2, 3]. La lamina fait aussi le lien entre le noyau et le cytosquelette car elle interagit avec des protéines transmembranaires telles que SUN1 (Sad1 and UNC84 domain containing 1) ou les protéines nesprines [4]. Ces propriétés de la lamina expliquent son rôle essentiel dans l’organisation structurelle de la cellule. De ce fait, les mutations des gènes codant pour les lamines sont associées à un large éventail de maladies, regroupées sous le nom de laminopathies [5], dont fait partie le syndrome de vieillissement prématuré Hutchinson-Gilford progeria syndrome (HGPS)

Robust-to-Illumination Face Localisation using Active Shape Models and Local Binary Patterns

This paper addresses the problem of locating facial features in images of frontal faces taken under different lighting conditions. The well-known Active Shape Model method proposed by Cootes {\it et al.} is extended to improve its robustness to illumination changes. For that purpose, we introduce the use of Local Binary Patterns (LBP). Three different incremental approaches combining ASM with LBP are presented: profile-based LBP-ASM, square-based LBP-ASM and divided-square-based LBP-ASM. Experiments performed on the standard and darkened image sets of the XM2VTS database demonstrate that the divided-square-based LBP-ASM gives superior performance compared to the state-of-the-art ASM. It achieves more accurate results and fails less frequently

Multiview Face Detection

In this document, we address the problem of multiview face detection. This work extends the frontal face detection system developed at the IDIAP Research Institute to multiview face detection. The main state-of-the art techniques are reviewed and a novel architecture is presented, based on a pyramid of detectors that are trained for different views of faces. The proposed approach robustly detects faces rotated up to -67.5 degree in the image plane and up to -90 degree out of the image plane. The system is real-time and achieves high performances on benchmark test sets, comparable to some state-of-the-art approaches