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FLATNESS FOR A STRONGLY DEGENERATE 1-D PARABOLIC EQUATION
We consider the degenerate equation on the unit interval , in the strongly degenerate case with adapted boundary conditions at and boundary control at . We use the flatness approach to construct explicit controls in some Gevrey classes steering the solution from any initial datum to zero in any time
Constraints on the spin-parity and anomalous HVV couplings of the Higgs boson in proton collisions at 7 and 8 TeV
see paper for full list of authorsInternational audienceThe study of the spin-parity and tensor structure of the interactions of the recently discovered Higgs boson is performed using the H to ZZ, Z gamma*, gamma* gamma* to 4 l, H to WW to l nu l nu, and H to gamma gamma decay modes. The full dataset recorded by the CMS experiment during the LHC Run 1 is used, corresponding to an integrated luminosity of up to 5.1 inverse femtobarns at a center-of-mass energy of 7 TeV and up to 19.7 inverse femtobarns at 8 TeV. A wide range of spin-two models is excluded at a 99% confidence level or higher, or at a 99.87% confidence level for the minimal gravity-like couplings, regardless of whether assumptions are made on the production mechanism. Any mixed-parity spin-one state is excluded in the ZZ and WW modes at a greater than 99.999% confidence level. Under the hypothesis that the resonance is a spin-zero boson, the tensor structure of the interactions of the Higgs boson with two vector bosons ZZ, Z gamma, gamma gamma, and WW is investigated and limits on eleven anomalous contributions are set. Tighter constraints on anomalous HVV interactions are obtained by combining the HZZ and HWW measurements. All observations are consistent with the expectations for the standard model Higgs boson with the quantum numbers J[PC]=0[++]
Patient-Specific Biomechanical Modeling of Cardiac Amyloidosis – A Case Study
International audienceWe present a patient-specific biomechanical modeling framework and an initial case study for investigating cardiac amyloidosis (CA). Our patient-specific heartbeat simulations are in good agreement with the data, and our model calibration indicates that the major effect of CA in the biophysical behavior lies in a dramatic increase of the passive stiffness. We also conducted a preliminary trial for predicting the effects of pharmacological treatments – which is an important clinical challenge – based on the model combined with a simple venous return representation. This requires further investigation and validation, albeit provides some valuable preliminary insight
Dynamics of a spherical capsule in a planar hyperbolic flow: influence of bending resistance
International audienceWe consider an initially spherical capsule freely suspended in a planar hyperbolic flow and study the influence of the wall bending resistance on the capsule dynamics. The capsule wall is assumed to be made of a three-dimensional homogeneous elastic material. The fluid-structure interaction between the capsule and the external flow is modeled numerically by coupling a boundary integral method with a shell finite element method. It is found that, for given three-dimensional wall mechanical properties, the capsule deformability is drastically reduced as the bending resistance is increased. But, if one expresses the same results as a function of the two-dimensional mechanical properties of the mid-surface, which is how the capsule wall is modeled in the thin-shell model, the capsule deformed shape is identical to the one predicted for a capsule devoid of bending resistance. The bending rigidity is found to have a negligible influence on the shape and deformation: the capsule main deformation mode is thus solely a function of the elastic stretching of the mid-surface. The wall bending resistance still plays a role locally in the regions where buckling occurs. Its influence is studied in the low flow strength regime, for which wrinkling of the wall is observed to persist at steady state. We show that the wrinkle wavelength only depends on the bending number, which compares the relative importance of bending and shearing phenomena, and provide the correlation law. This result is interesting as it allows bending resistance to be estimated from experiments on capsules in a planar hyperbolic flow at low flow strength
Collins asymmetries in inclusive charged and pairs produced in annihilation
See paper for full list of authors - 7 pages, 4 postscript figures, 5 pages of Supplemental MaterialInternational audienceWe present measurements of Collins asymmetries in the inclusive process , , at the center-of-mass energy of 10.6 GeV, using a data sample of 468 fb collected by the BaBar experiment at the PEP-II factory at SLAC National Accelerator Center. Considering hadrons in opposite thrust hemispheres of hadronic events, we observe clear azimuthal asymmetries in the ratio of unlike- to like-sign, and unlike- to all charged pairs, which increase with hadron energies. The asymmetries are similar to those measured for the pairs, whereas those measured for high-energy pairs are, in general, larger
Passive coherent combining of CEP-stable few-cycles pulses from a temporally divided hollow fiber compressor (Orale)
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Model Exploration Using OpenMOLE - a workflow engine for large scale distributed design of experiments and parameter tuning
International audienceOpenMOLE is a scientific workflow engine with a strong emphasis on workload distribution.Workflows are designed using a high level Domain Specific Language (DSL) built on top of Scala. It exposes natural parallelism constructs to easily delegate the workload resulting from a workflow to a wide range of distributed computing environments. In this work, we briefly expose the strong assets of OpenMOLE and demonstrate its efficiency at exploring the parameter set of an agent simulation model. We perform a multi-objective optimisation on this model using computationally expensive Genetic Algorithms (GA). OpenMOLE hides the complexity of designing such an experiment thanks to its DSL, and transparently distributes the optimisation process. The example shows how an initialisation of the GA with a population of 200,000 individuals can be evaluated in one hour on the European Grid Infrastructure
De la Routine Humaine vers des Réseaux Mobiles Plus Efficaces
The proliferation of pervasive communication caused a recent boost up on the mobile data usage, which network operators are not always prepared for. The main origin of the mobile network demands are smartphone devices. From the network side those devices may be seen as villains for imposing an enormous traffic, but from the analytical point of view they provide today the best means of gathering users information about content consumption and mobility behavior on a large scale. Understanding users' mobility and network behavior is essential in the design of efficient communication systems. We are routinary beings. The routine cycles on our daily lives are an essential part of our interface with the world. Our habits define, for instance, where we are going Saturday night, or what is the typical website for the mornings of Monday. The repetitive behavior reflects on our mobility patterns and network activities. In this thesis we focus on metropolitan users generating traffic demands during their normal daily lives. We present a detailed study on both users' routinary mobility and routinary network behavior. As a study of case where such investigation can be useful, we propose a hotspot deployment strategy that takes into account the routine aspects of people's mobility.We first investigate urban mobility patterns. We analyze large-scale datasets of mobility in different cities of the world, namely Beijing, Tokyo, New York, Paris, San Francisco, London, Moscow and Mexico City. Our contribution is this area is two-fold. First, we show that there is a similarity on people's mobility behavior regardless the city. Second, we unveil three characteristics present on the mobility of typical urban population: repetitiveness, usage of shortest-paths, and confinement. Those characteristics undercover people's tendency to revisit a small portion of favorite venues using trajectories that are close to the shortest-path. Furthermore, people generally have their mobility restrict to a dozen of kilometers per day.We then investigate the users' traffic demands patterns. We analyze a large data set with 6.8 million subscribers. We have mainly two contributions in this aspect. First, a precise characterization of individual subscribers' traffic behavior clustered by their usage patterns. We see how the daily routine impacts on the network demands and the strong similarity between traffic on different days. Second, we provide a way for synthetically, still consistently, reproducing usage patterns of mobile subscribers. Synthetic traces offer positive implications for network planning and carry no privacy issues to subscribers as the original datasets.To assess the effectiveness of these findings on real-life scenario, we propose a hotspot deployment strategy that considers routine characteristics of mobility and traffic in order to improve mobile data offloading. Carefully deploying Wi-Fi hotspots can both be cheaper than upgrade the current cellular network structure and can concede significant improvement in the network capacity. Our approach increases the amount of offload when compared to other solution from the literature.L’omniprésence des communications a entraîné une récente augmentation des volumes de données mobiles, pour laquelle les opérateurs n’étaient pas toujours préparés. Les smartphones sont les plus gros consommateurs de données mobiles. Ces appareils peuvent être considérés comme méchants à cause d’un tel traffic, mais d’un point de vue analytique ils fournissent, aujourd’hui un des meilleurs moyens afin de collecter les données sur le comportement de consommation et de mobilité de grande échelle. Comprendre le comportement des utilisateurs sur leur mobilité et leur connectivité est nécessaire à la création d’un système de communication effectifs. Nous sommes routiniers. Ces cycles routiniers sont une grande partie de nos interactions avec le monde. Par exemple, nos habitudes definissent ce que l’on va faire le samedi ou les sites que nous consultons le lundi matin. Ces comportements répétés reflètent nos déplacements et activités en ligne. Dans cette thèse, nous allons nous concentrer sur les demandes de traffic générées par les usagers métropolitains durant leurs activités quotidiennes. Nous présentons une étude détaillée des usagers selon les comportements routiniers de mobilité ou d’activité sur internet. Dans une étude de cas, ou cette enquête serait utile, nous proposons une stratégies de déploiement de points de accès qui prendra en compte les aspects routiniers de la mobilités des utilisateurs.Nous étudirons en premier lieu, les modèles de mobilité en milieu urbain. Nous analyserons les données de mobilité à grande échelle dans de grandes villes comme Beijing, Tokyo, New York, Paris, San Francisco, London, Moscow, Mexico City. Cette contribution se fait en deux étapes. Premièrement, nous observerons les similitudes des déplacements peu importe la ville concernée. Ensuite, nous mettrons en évidence trois caractéristiques présentes dans les déplacements d’une population urbaine typique: Répétivité, utilisation de raccourcis, confinement. Ces caractéristiques sont dues à la tendance qu’ont les personnes à revisiter les même rues en utilisant les trajectoires proches du chemin le plus court. D’ailleurs, les personnes ont une mobilité quotidienne inférieure à dix kilomètres par jour.Nous avons ensuite étudié les modèles de demandes de traffic en utilisant une base de données comprenant les données de 6.8 millions d’utilisateurs. Pour cela nous avons principalement deux contributions. Premièrement, une caractérisation précise des comportements de consommation des utilisateurs agrégés par modèle. Nous pouvons voir comment les routines quotidiennes impactent nos demandes de connections et la similarité de ce traffic en fonction des jours. En suite, nous fournirons un moyen de reproduire artificiellement mais avec cohérence les modèles des utilisateurs de données mobiles. Ces données synthétisées ont l’avantage de permettre la planification du réseau sans information sur la vie privées de utilisateurs comme les bases de données d’origine.Afin d’évaluer l’efficacité de ces informations dans un scénario grandeur nature, nous proposerons une stratégie de deploiement de points de accès qui prend en compte les caractéristiques routinières en terme de déplacement et de demande de trafic dans le but d’améliorer la décharge de données mobile. Déployer correctement des points de accès WiFi peut être moins cher que d’améliorer l’infrastructure de réseaux mobiles, et peut permettre d’améliorer considérablement la capacité du réseau. Notre approche améliore l’évacuation de trafic comparée aux autres solutions disponibles dans la littérature
Neutrino-production of a charmed meson and the transverse spin structure of the nucleon
International audienceWe calculate the amplitude for exclusive neutrino production of a charmed meson on an unpolarized target, in the colinear QCD approach where generalized parton distributions (GPDs) factorize from perturbatively calculable coefficient functions. We demonstrate that the transversity chiral odd GPDs contribute to the transverse cross section if the hard amplitude is calculated up to order mc/Q. We show how to access these GPDs through the azimuthal dependence of the νN → µ − D + N differential cross section. Introduction
Testing climate models using an impact model: what are the advantages?
International audienceGlobal and regional climate model (GCM and RCM) outputs are often used as climate forcing for ecological impact models, and this potentially results in large cumulative errors because information and error are passed sequentially along the modeling chain from GCM to RCM to impact model. There are also a growing number of Earth system modeling platforms in which climate and ecological models are dynamically coupled, and in this case error amplification due to feedbacks can lead to even more serious problems. It is essential in both cases to rethink the organization of evaluation which typically relies on independent validation at each successive step, and to rely more heavily on analyses that cover the full modeling chain and thus require stronger interactions between climate and impact modelers. In this paper, we illustrate the benefits of using impact models as an additional source of information for evaluating climate models. Four RCMs that are part of the HyMeX (Hydrological cycle in Mediterranean EXperiment) and Mediterranean CORDEX projects (MED-CORDEX) were tested with observed climatology and a process-based model of European beech (Fagus sylvatica L.) tree growth and forest ecosystem functioning that has been rigorously validated. This two part analysis i) indicates that evaluation of RCMs on climate variables alone may be insufficient to determine the suitability of RCMs for studies of climate-forest interactions and ii) points to areas of improvement in these RCMs that would improve impact studies or behavior in coupled climate-ecosystem models over the spatial domain studied