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  • Publication . Preprint . Article . Conference object . 2018
    Open Access English
    Authors: 
    Moser, Daniel; Abele, Hartmut; Bosina, Joachim; Fillunger, Harald; Soldner, Torsten; Wang, Xiangzun; Zmeskal, Johann; Konrad, Gertrud;
    Publisher: HAL CCSD
    Country: France
    Project: FWF | Particles and Interaction... (W 1252)

    The beta decay of the free neutron provides several probes to test the Standard Model of particle physics as well as to search for extensions thereof. Hence, multiple experiments investigating the decay have already been performed, are under way or are being prepared. These measure the mean lifetime, angular correlation coefficients or various spectra of the charged decay products (proton and electron). NoMoS, the Neutron decay prOducts MOmentum Spectrometer, presents a novel method of momentum spectroscopy: it utilizes the $R \times B$ drift effect to disperse charged particles dependent on their momentum in an uniformly curved magnetic field. This spectrometer is designed to precisely measure momentum spectra and angular correlation coefficients in free neutron beta decay to test the Standard Model and to search for new physics beyond. With NoMoS, we aim to measure inter alia the electron-antineutrino correlation coefficient $a$ and the Fierz interference term $b$ with an ultimate precision of $\Delta a/a < 0.3\%$ and $\Delta b < 10^{-3}$ respectively. In this paper, we present the measurement principles, discuss measurement uncertainties and systematics, and give a status update. Comment: 7 pages, 4 figures, accepted to the Proceedings of the International Workshop on Particle Physics at Neutron Sources PPNS 2018, Grenoble, France, May 24-26, 2018

  • Publication . Conference object . Other literature type . Part of book or chapter of book . 2016
    Open Access English
    Authors: 
    Etienne Parizet; Ryan Robart; Perceval Pondrom; Jean-Christophe Chamard; Guillaume Baudet; David Quinn; Karl Janssens; Manfred Haider;
    Publisher: HAL CCSD
    Country: France
    Project: EC | EVADER (285095)

    International audience; Electric or hybrid vehicles are very silent, which represents a major advantage for the reduction of noise annoyance in urban areas. But this makes them dangerous for pedestrians, especially vulnerable ones as visually-impaired people. Current solutions consist in using warning sound so that the exterior noise of an electric vehicle is as high as for a conventional one. This may cancel the benefit of electric vehicles for the reduction of sound annoyance. The eVADER project (funded by the European Commission) aims at proposing a prototype car which combines a high safety and a low noise level. A part of the the work program consisted in perceptual studies. The goal of these studies was to evaluate the influence of various timbre parameters on the detectability and the unpleasantness of a warning sound. Results show that it is possible to make an electric vehicle easily detected while keeping its sound level much lower than the one of a conventional car.

  • Publication . Part of book or chapter of book . Conference object . Preprint . 2019
    Open Access English
    Authors: 
    Quentin Roy; Camelia Zakaria; Simon T. Perrault; Mathieu Nancel; Wonjung Kim; Archan Misra; Andy Cockburn;
    Publisher: HAL CCSD
    Country: France

    Part 8: Pointing, Touch, Gesture and Speech-Based Interaction Techniques; International audience; Eyewear displays allow users to interact with virtual content displayed over real-world vision, in active situations like standing and walking. Pointing techniques for eyewear displays have been proposed, but their social acceptability, efficiency, and situation awareness remain to be assessed. Using a novel street-walking simulator, we conducted an empirical study of target acquisition while standing and walking under different levels of street crowdedness. We evaluated three phone-based eyewear pointing techniques: indirect touch on a touchscreen, and two in-air techniques using relative device rotations around forward and a downward axes. Direct touch on a phone, without eyewear, was used as a control condition. Results showed that indirect touch was the most efficient and socially acceptable technique, and that in-air pointing was inefficient when walking. Interestingly, the eyewear displays did not improve situation awareness compared to the control condition. We discuss implications for eyewear interaction design.

  • Open Access English
    Authors: 
    Antonio Alguacil; Michaël Bauerheim; Marc C. Jacob; Stéphane Moreau;
    Publisher: HAL CCSD
    Country: France

    International audience; A deep learning surrogate for the direct numerical prediction of two-dimensional acoustic waves propagation and scattering with obstacles is developed through an auto-regressive spatio- temporal convolutional neural network. A single database of high-fidelity lattice Boltzmann temporal simulations is employed in the training of the network, achieving accurate predictions for long simulation times for a variety of test cases, representative of bounded and unbounded configurations. The capacity of the network to extrapolate outside the manifold of examples seen during the training phase is demonstrated by the obtaining of accurate acoustic predic- tions for relevant applications, such as the scattering of acoustic waves on an airfoil trailing edge, an engine nacelle or in-duct propagation. The method is tested for two types of input normalizations, coupled with an a-posteriori correction which improves the acoustic energy conservation of the predictions. The use of an adaptive local normalization along with the physics-based energy conservation results in an error reduction for all the studied cases.

  • English
    Authors: 
    Xavier Bultel; Sébastien Gambs; David Gérault; pascal lafourcade; Cristina Onete; Jean-Marc Robert;
    Publisher: HAL CCSD
    Country: France
    Project: NSERC

    International audience; Les communications sans contact sont omniprésentes dans notre quotidien, allant des badges de contrôle d'accès au passeport électronique. Ces systèmes sont sensibles aux attaques par relais, dans lesquelles un adversaire transfère simplement les messages entre le prouveur et le vérifieur pour usurper l'identité du prouveur. Les protocoles délimiteurs de distance (distance-bounding) ont été ont ntroduits pour contrer ces attaques en assurant une borne sur la distance entre le prouveur et le vérifieur grâcè a la mesure du temps des communications. Par la suite de nombreux travaux ont amélioré la sécurité de ces protocoles, mais ont aussi cherché à assurer le respect de la vie privée face à des adversaires actifs et également face à des vérifieurs malicieux. En particulier, une menace difficile à prévenir est la fraude terroriste, où un prouveur lointain coopère avec un complice proche pour tromper le vérifieur. La contre-mesure usuelle pour cette menace est de rendre impossible l'action du complice sans l'aide du prouveur lointain, à moins que le prouveur ne lui donne suffisamment d'information pour qu'il retrouve sa clef privée et puisse ainsi toujours se faire passer pour le prouveur. Dans cet article, nous proposons une nouvelle approche où le prouveur ne révèle pas sa clef privée mais utilise une clef de session avec une signature de groupe, la rendant ainsi utilisable plusieurs fois. Ceci permet à un adversaire d'usurper l'identité du prouveur sans même connaître sa clef de signature. Grâce à cette approche nous proposons SPADE le premier protocole de délimiteur de distance qui est anonyme, révocable et formellement prouvé sûr. Mots-clefs : Protocole délimiteur de distance (Distance Bounding), Sécurité, résitance à la fraude terroriste.

  • Publication . Conference object . 2004
    English
    Authors: 
    Bengio, Yoshua; Monperrus, Martin;
    Publisher: HAL CCSD
    Project: NSERC

    International audience; We claim and present arguments to the effect that a large class of manifold learning algorithms that are essentially local and can be framed as kernel learning algorithms will suffer from the curse of dimensionality, at the dimension of the true underlying manifold. This observation suggests to explore non-local manifold learning algorithms which attempt to discover shared structure in the tangent planes at different positions. A criterion for such an algorithm is proposed and experiments estimating a tangent plane prediction function are presented, showing its advantages with respect to local manifold learning algorithms: it is able to generalize very far from training data (on learning handwritten character image rotations), where a local non-parametric method fails.

  • Publication . Preprint . Article . Conference object . 2012
    Open Access English
    Authors: 
    Roehlly, Y.; Burgarella, D.; Buat, V.; Giovannoli, É.; Noll, S.; Serra, P.;
    Publisher: HAL CCSD
    Country: France

    We present CIGALE (Burgarella et al. 2005; Noll et al. 2009), a software developed at the Laboratoire d'Astrophysique de Marseille to fit galaxy spectral energy distributions from the rest-frame far-UV to far-IR wavelength range, and to derive some of their physical parameters. We also give some examples of scientific results obtained with CIGALE. 4 pages, 2 figures, proceeding of a poster to be presented at ADASS XXI in Paris

  • Closed Access English
    Authors: 
    Jianjun Yang; Jin Liu; Yongfeng Hu; Cornelia Rumpel; Nanthi Bolan; Donald L. Sparks;
    Publisher: HAL CCSD
    Countries: Australia, France
    Project: ARC | Discovery Projects - Gran... (DP140100323)

    International audience; Multivalent cation interaction and mineral association play a vital role in organic carbon (OC) stability in tropical soils. However, the retention mechanisms of OC in mineral-cation-OC systems remain largely unclear at the molecular level. Of all OC forms, low molecular weight organic acids (LMWOAs) are readily biodegradable. Given the general acidic conditions and dominance of kaolinite in tropical soils, we investigated the retention mechanisms of malic acid (MA) in kaolinite-Fe(III)-MA systems with various Fe/MA molar ratios at pH similar to 3.5 using Fe K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy. Our results indicated the formed ferrihydrite mainly contributed to the enhanced MA retention through adsorption and/or coprecipitation at high Fe/MA molar ratios in kaolinite-Fe(III)-MA systems relative to kaolinite-MA systems. With the decrease of Fe/MA molar ratios, ternary complexation of MA with kaolinite via a tetrahedral Fe bridge occurred in kaolinite-Fe(III)-MA systems. This study highlighted the significant impact of Fe speciation on MA retention mechanisms in kaolinite-Fe(III)-MA systems under acidic conditions, and clearly showed the impact of ferrihydrite-induced adsorption/coprecipitation and Fe-bridged ternary complexation on MA retention in ternary kaolinite-Fe(III)MA systems, which will enhance our understanding of the dynamics of MA and other LMWOAs in tropical soils.

  • Open Access
    Authors: 
    Ebizimoh Abodei; Alex Norta; Irene Azogu; Chibuzor Udokwu; Dirk Draheim;
    Publisher: Springer International Publishing
    Country: France

    Part 7: Digital Governance; International audience; Infrastructural development is a significant determinant of economic growth. It remains an elusive pursuit for many developing economies suffering from public infrastructural project failures. Although the causes of these failures are identifiable, they remain persistent. Government corruption has been identified as the primary cause of project failures amidst a host of other causal factors, spurred by the ambiguity in public service administration. These factors heighten capital expenditures and hence, the need for more transparent systems in public infrastructural project planning and -delivery. This research uses a case-study methodology to examine the importance of public involvement in addressing the causes of failures in public infrastructural project planning and -delivery. Using Nigeria as a case, the findings from conducted interviews and a document review support the proposition of a technologically collaborative approach in addressing the causes of public infrastructural project failures. The institutionalization of transparency-enhancing blockchain systems are vital in government and public involvement in the processes of public infrastructural project planning and -delivery.

  • French
    Authors: 
    Allard, Daniele; Mizoguchi, Riichiro; Bourdeau, Jacqueline;
    Publisher: HAL CCSD
    Country: France

    This research project aims to design a CALL system (Computer-Assisted Language Learning). The goal of the system is to help users overcome cross-linguistic difficulties, that is to say, transfer and interference stemming from a native language (L1) in the process of acquiring a second or foreign language (L2). It is built following an ontological engineering methodology, which is well-known in the artificial intelligence community. In this article, we describe what is cross-linguistic influence, provide a concrete example of what it might entail, and briefly explain how the system might work along with our research methodology.

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