HAL Université de Toulouse, et Toulouse INP
Not a member yet
159308 research outputs found
Sort by
A test for LISA foreground Gaussianity and stationarity. II. Extreme mass-ratio inspirals
No full textInternational audienceExtreme Mass Ratio Inspirals (EMRIs) are key observational targets for the Laser Interferometer Space Antenna (LISA) mission. Unresolvable EMRI signals contribute to forming a gravitational wave background (GWB). Characterizing the statistical features of the GWB from EMRIs is of great importance, as EMRIs will ubiquitously affect large segments of the inference scheme. In this work, we apply a frequentist test for GWB Gaussianity and stationarity, exploring three astrophysically-motivated EMRI populations. We construct the resulting signal by combining state-of-the-art EMRI waveforms and a detailed description of the LISA response with time-delay interferometric variables. Depending on the brightness of the GWB, our analysis demonstrates that the resultant EMRI foregrounds show varying degrees of departure from the usual statistical assumptions that the GWBs are both Gaussian and Stationary. If the GWB is non-stationary with non-Gaussian features, this will challenge the robustness of Gaussian-likelihood model, when applied to global inference results, e.g. foreground estimation, background detection, and individual-source parameters reconstruction
Automatic Inbetweening for Stroke‐Based Painterly Animation
No full textInternational audiencePainterly 2D animation, like the paint-on-glass technique, is a tedious task performed by skilled artists, primarily using traditional manual methods. Although CG tools can simplify the creation process, previous works often focus on temporal coherence, which typically results in the loss of the handmade look and feel. In contrast to cartoon animation, where regions are typically filled with smooth gradients, stroke-based stylized 2D animation requires careful consideration of how shapes are filled, as each stroke may be perceived individually. We propose a method to generate intermediate frames using example keyframes and a motion description. This method allows artists to create only one image for every five to 10 output images in the animation, while the automatically generated intermediate frames provide plausible inbetween frames
Optimization-Aided Construction of Multivariate Chebyshev Polynomials
No full textInternational audienceThis article is concerned with an extension of univariate Chebyshev polynomials of the first kind to the multivariate setting, where one chases best approximants to specific monomials by polynomials of lower degree relative to the uniform norm. Exploiting the Moment-SOS hierarchy, we devise a versatile semidefinite-programming-based procedure to compute such best approximants, as well as associated signatures. Applying this procedure in three variables leads to the values of best approximation errors for all mononials up to degree six on the euclidean ball, the simplex, and the cross-polytope. Furthermore, inspired by numerical experiments, we obtain explicit expressions for Chebyshev polynomials in two cases unresolved before, namely for the monomial on the euclidean ball and for the monomial on the simplex
Stated skein modules of 3-manifolds and TQFT
No full text37 pagesInternational audienceWe study the behaviour of the Kauffman bracket skein modules of 3-manifolds under gluing along surfaces. For this purpose we extend the notion of Kauffman bracket skein modules to -manifolds with marking consisting of open intervals and circles in the boundary. The new module is called the stated skein module. The first main results concern non-injectivity of certain natural maps defined when forming connected sums along a sphere or along a closed disk. These maps are injective for surfaces, or for generic quantum parameter, but we show that in general they are not injective when the quantum parameter is a root of 1. The result applies to the classical skein modules as well. A particular interesting result is that when the quantum parameter is a root of 1, the empty skein is zero in a connected sum where each constituent manifold has non-empty marking. We also prove various non injectivity results for the Chebyshev-Frobenius map and the natural map induced by the deletion of marked balls. We then consider the general case of gluing along a surface, showing that the stated skein module can be interpreted as a monoidal symmetric functor from a category of "decorated cobordisms" to a Morita category of algebras and their bimodules. We apply this result to deduce several properties of stated skein modules as a Van-Kampen like theorem as well as a computation through Heegaard decompositions and a relation to Hochshild homology for trivial circle bundles over surfaces
Genetics of body weight and length of Large White piglets and relationship to maternal performance
No full textInternational audienceBody weight and body metrics of newborn piglets reflect their level of development. We studied a Large White population raised in a single experimental herd. Survival and growth performance of 10,101 piglets originating from 689 litters were analysed. In 440 of these litters, 1,320 piglets contrasting for birth weight were recorded for body length and circumference. At piglet level, the estimated direct and maternal heritability values were were h²d=0.02 and h²m=0.13 for birth weight, h²d=0.65 and h²m=0.21 for the ponderal index and h²d=0.23 and h²m=0.01 for the ratio of circumference to body length. The genetic correlation between the ponderal index and litter size and gestation length tended to be negative
Exact asymptotic characterisation of running time for approximate gradient descent on random graphs
No full textInternational audienceIn this work we study the time complexity for the search of local minima in random graphs whose vertices have i.i.d. cost values. We show that, for Erd\"os-R\'enyi graphs with connection probability given by (with and ), a family of local algorithms that approximate a gradient descent find local minima faster than the full gradient descent. Furthermore, we find a probabilistic representation for the running time of these algorithms leading to asymptotic estimates of the mean running times
Measurement of production in association with additional -jets in the final state in proton-proton collisions at =13 TeV with the ATLAS detector
No full textInternational audienceThis paper presents measurements of top-antitop quark pair () production in association with additional -jets. The analysis utilises 140 fb of proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 13 TeV. Fiducial cross-sections are extracted in a final state featuring one electron and one muon, with at least three or four -jets. Results are presented at the particle level for both integrated cross-sections and normalised differential cross-sections, as functions of global event properties, jet kinematics, and -jet pair properties. Observable quantities characterising -jets originating from the top quark decay and additional -jets are also measured at the particle level, after correcting for detector effects. The measured integrated fiducial cross-sections are consistent with predictions from various next-to-leading-order matrix element calculations matched to a parton shower within the uncertainties of the predictions. State-of-the-art theoretical predictions are compared with the differential measurements; none of them simultaneously describes all observables. Differences between any two predictions are smaller than the measurement uncertainties for most observables
Impulsive switching signals with functional inequalities: Stability analysis using hybrid systems framework
No full textInternational audienceIn this work, we introduce a class of impulsive switching signals described via functional inequalities which govern the switching among different modes with state resets. By choosing the parameters of the inequalities appropriately, we can recover several known classes of switching signals and also allow for signals that depend on time, mode or state of the system. Signals from this class can also be generated online via the use of an auxiliary timer while the dynamical system is running. Via a multiple Lyapunov functions approach, we provide sufficient conditions on the functional parameters of the switching signal which ensure that the equilibrium is globally asymptotically stable (GAS) for autonomous impulsive switched system. In case of inputs, similar methodology is used to provide sufficient conditions for input-to-state stability (ISS) and integral-input-tostate stability (iISS) uniformly over the proposed class of impulsive switching signals. As case studies, we consider switched systems which do not satisfy ISS (respectively, iISS) property for switching signals with arbitrarily large dwell-times but they are shown to be ISS (resp. iISS) for our proposed class of impulsive switchings signals described via functional inequalities.</div
Unconventional Scalings of Quantum Entropies in Long-Range Heisenberg Chains
No full textInternational audienceIn this work, building on state-of-the-art quantum Monte Carlo simulations, we perform systematic finite-size scaling of both entanglement and participation entropies for long-range Heisenberg chain with unfrustrated power-law decaying interactions. We find distinctive scaling behaviors for both quantum entropies in the various regimes explored by tuning the decay exponent , thus capturing non-trivial features through logarithmic terms, beyond the case of linear Nambu-Goldstone modes. Our systematic analysis reveals that the quantum entanglement information, hidden in the scaling of the two studied entropies, can be obtained to the same level of order parameters and other usual finite-size observables of quantum many-body lattice models. The analysis and results obtained here can readily apply to more quantum criticalities in 1D and 2D systems
L'Influence des laboratoires d'innovation publique sur le développement de l'ambidextrie au sein du secteur public
No full textInternational audienceAmbidexterity has become a major issue for public organizations as they manage increasingly strong contradictory pressures to optimize existing processes while innovating. Moreover, although public innovation laboratories are emerging, their influence on the development of ambidexterity remains largely unexplored. Our research aims to understand how innovation laboratories contribute to the formation of individual ambidexterity within the public sector. Drawing from three case studies, this research underscores the influence of these labs on public ambidexterity through the development of innovations by non-specialized actors and the deployment and reuse of innovative managerial practices and techniques outside the i-labs