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  • Open Access English
    Authors: 
    Serpolay-Besson, Estelle; Goldringer, Isabelle; Aubin, Thibaud;
    Publisher: HAL CCSD
    Country: France
    Project: EC | SOLIBAM (245058)

    A group of farmers of the Poitou region in France, already expert in on-farm maize population selection, would like to acquire the same know-how with wheat and legume in co-breeding. They asked INRA to build a participatory breeding project with them with this view. The first year was dedicated to the cultivation and common evaluation of several varieties on a platform. More than having learnt how to breed wheat, the farmers say they have learnt how to observe wheat and are now able to do on-farm trial on their own farms.

  • 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.

  • Open Access English
    Authors: 
    Paolo Zanini; Marco Congedo; Christian Jutten; Salem Said; Yannick Berthoumieu;
    Publisher: HAL CCSD
    Country: France
    Project: EC | CHESS (320684)

    International audience; The study of P(m), the manifold of m x m symmetric positive definite matrices, has recently become widely popular in many engineering applications, like radar signal processing, mechanics , computer vision, image processing, and medical imaging. A large body of literature is devoted to the barycentre of a set of points in P(m) and the concept of barycentre has become essential to many applications and procedures, for instance classification of SPD matrices. However this concept is often used alone in order to define and characterize a set of points. Less attention is paid to the characterization of the shape of samples in the manifold, or to the definition of a probabilistic model, to represent the statistical variability of data in P(m). Here we consider Gaussian distributions and mixtures of Gaussian distributions on P(m). In particular we deal with parameter estimation of such distributions. This problem, while it is simple in the manifold P(2), becomes harder for higher dimensions, since there are some quantities involved whose analytic expression is difficult to derive. In this paper we introduce a smooth estimate of these quantities using convex cubic spline, and we show that in this case the parameters estimate is coherent with theoretical results. We also present some simulations and a real EEG data analysis.

  • English
    Authors: 
    Benjamin Hervy; Florent Laroche; Jean-Louis Kerouanton; Alain Bernard;
    Publisher: HAL CCSD
    Country: France
    Project: EC | VISIONAIR (262044)

    International audience; In this paper, we illustrate how historical data can be capitalised for future virtual visualization applications. We will demonstrate our proposition thanks to a research and development project started in 2008 about a mock-up of Nantes (french city) harbour. This mock-up is an historic and geographic witness of the country it represents. The amount of available knowledge with such a historic witness is significant and can be useful for many experts and obviously for museum public. What we aim to do is to capitalise the whole knowledge related to this patrimonial object before designing any end user's application. Digital technologies such as 3D numerisation, virtual reality and cognitive infocommunications will help us to achieve this goal.

  • Closed Access English
    Authors: 
    Maira Possas; Lionel Rousseau; Farbod Ghassemi; Gaelle Lissorgues; Emmanuel Scorsone; Philippe Bergonzo;
    Publisher: HAL CCSD
    Country: France
    Project: EC | SNIFFER (285203)

    International audience; The exceptional chemical, mechanical and thermal properties of diamond make this material the ideal choice for resonant MEMS. Micro-cantilevers designed for biochemical applications have been fabricated using CVD diamond. In this work, the mechanical properties of these cantilevers were investigated by two different techniques: bending test using a Contact Surface Profilometer and resonant test, using a Laser Doppler Vibrometer. The Young's Modulus of diamond thin film was estimated by these two tests. For the resonance test, the estimated values are comprised between 930 and 1300 GPa while bending test gives values between 950 and 1030 GPa. The load-displacement characteristics and the fracture point (or ultimate stress) have also been investigated.

  • Open Access English
    Authors: 
    Cédric Fleury; Thierry Duval; Valérie Gouranton; Anthony Steed;
    Publisher: HAL CCSD
    Country: France
    Project: EC | VISIONAIR (262044)

    International audience; In the context of scientific data analysis, we propose to compare a remote collaborative manipulation technique with a single user manipulation technique. The manipulation task consists in positioning a clipping plane in order to perform cross-sections of scientific data which show several points of interest located inside this data. For the remote collaborative manipulation, we have chosen to use the 3-hand manipulation technique proposed by Aguerreche et al. which is very suitable with a remote manipulation of a plane. We ran two experiments to compare the two manipulation techniques with some participants located in two different countries. These experiments showed that the remote collaborative manipulation technique was significantly more efficient than the single user manipulation when the three points of interest were far from each other inside the scientific data and, consequently, when the manipulation task was harder and required more precision. When the three points of interest were close from each other, there was not significant difference between the two manipulation techniques.

  • English
    Authors: 
    Christine Poncet; Cécile Bresch; Hicham Fatnassi; Ludovic Mailleret; Alexandre Bout; G. Perez; Jeannine Pizzol; L. Carlesso; B. Paris; Pia Parolin;
    Publisher: HAL CCSD
    Country: France
    Project: EC | PURE (265865)

    International audience; Protected cultivation or Controlled Environment Agriculture (CEA) system has increased tenfold in the last 25 years thanks to tremendous scientific and technical breakthroughs, mainly directed to increasing crop yields and adapting to tough ambient conditions. Currently, greenhouse areas are still spreading and the CEA system is one of the keystones for the agriculture forecasting scenario. However, the environmental acceptability of this very intensive agro-ecosystem is now being questioned. Energy inputs are source of the main economic and environmental weakness, especially for high-tech greenhouses, where IPM is well-established. Pesticides, common in low-cost greenhouses systems, are a major barrier-to IPM. To design and manage more robust CEA systems, both technological and ecological approaches have been chosen. This allowed for increased consideration of IPM issues among global greenhouse engineering innovation and better use of greenhouse system capacities to enhance dedicated IPM high-tech tools and management practices. On the other hand, ecological concepts were used to determine and characterize complex biotic interactions that lead to question the tenant of biological control as soon as IPM is implemented in greenhouses with sub-optimum physical pest control means. More specifically, microclimate at the boundary layer level has been investigated both from a physical and biological point of view in order to determine the best climate preferences of the main pests and beneficials. By the same token, the efficiency of diverse biocontrol plants to provide accurate shelter to natural enemies has been assessed

  • Publication . Part of book or chapter of book . Conference object . 2021
    Open Access English
    Authors: 
    Raphaël Monat; Abdelraouf Ouadjaout; Antoine Miné;
    Publisher: HAL CCSD
    Country: France
    Project: EC | MOPSA (681393)

    International audience; Modern programs are increasingly multilanguage, to benefit from each programming language's advantages and to reuse libraries. For example, developers may want to combine high-level Python code with low-level, performance-oriented C code. In fact, one in five of the 200 most downloaded Python libraries available on GitHub contains C code. Static analyzers tend to focus on a single language and may use stubs to model the behavior of foreign function calls. However, stubs are costly to implement and undermine the soundness of analyzers. In this work, we design a static analyzer by abstract interpretation that can handle Python programs calling C extensions. It analyses directly and fully automatically both the Python and the C source codes. It reports runtime errors that may happen in Python, in C, and at the interface. We implemented our analysis in a modular fashion: it reuses off-the-shelf C and Python analyses written in the same analyzer. This approach allows sharing between abstract domains of different languages. Our analyzer can tackle tests of real-world libraries a few thousand lines of C and Python long in a few minutes.

  • Closed Access English
    Authors: 
    Alexandra Covaci; Anne-Hélène Olivier; Franck Multon;
    Publisher: HAL CCSD
    Countries: France, United Kingdom, United Kingdom
    Project: EC | VISIONAIR (262044), EC | VISIONAIR (262044)

    Best Paper Award; International audience; The use of Virtual Reality (VR) in sports training is now widely studied with the perspective to transfer motor skills learned in virtual environments (VEs) to real practice. However precision motor tasks that require high accuracy have been rarely studied in the context of VE, especially in Large Screen Image Display (LSID) platforms. An example of such a motor task is the basketball free throw, where the player has to throw a ball in a 46cm wide basket placed at 4.2m away from her. In order to determine the best VE training conditions for this type of skill, we proposed and comparedthree training paradigms. These training conditions were used to compare the combinations of different user perspectives: first (1PP) and third-person (3PP) perspectives, and the effectiveness of visual guidance. We analysed the performance of eleven amateur subjects who performed series of free throws in a real and immersive 1:1 scale environment under the proposed conditions. The results show that ball speed at the moment of the release in 1PP was significantly lower compared to real world, supporting the hypothesis that distance is underestimated in large screen VEs. Howeverball speed in 3PP condition was more similar to the real condition, especially if combined with guidance feedback. Moreover, when guidance information was proposed, the subjects released the ball at higher - and closer to optimal - position (5-7% higher compared to no-guidance conditions). This type of information contributes to better understand the impact of visual feedback on the motor performance of users who wish to train motor skills using immersive environments. Moreover, this information can be used by exergames designers who wish to develop coaching systems to transfer motor skills learned in VEs to real practice.

  • English
    Authors: 
    David Chèze; Antoine Leconte;
    Publisher: HAL CCSD
    Country: France
    Project: EC | SunHorizon (818329)

    International audience; Despite the huge primary energy consumption associated with heating and cooling (H&C) demand in EU building stock, the share of installed renewable H&C solutions is still marginal (i.e. 5%). In order to speed up a transition towards the widespread application of renewable H&C in buildings, innovative solutions must be designed to compete against traditional solutions. SunHorizon project aims to unlock the potential for a user-friendly and cost-effective solution based on an optimized design and combination of commercial innovative solar technologies (thermal or/and PV) and Heat Pumps (HP). This paper aims to present how are performing experimentally two hybrid concepts, out of four in the whole project, that are coupling solar thermal and PV panels with heat pumps to satisfy thermal and electricity energy demand of residential buildings in Riga (Latvia) and Piera (Spain). Following hardware-in-the-loop approach, specific short test sequences are developed first for each of the two Technology Packages (TP) that allow for extrapolation of the measurements to annual seasonal performance figures including electricity self-consumption in addition to renewable heating and cooling indicators.

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