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  • 2012-2021
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  • Mémoires en Sciences de l'Information et de la Communication
  • Rural Digital Europe

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  • English
    Authors: 
    Sébastien GADAL;
    Publisher: HAL CCSD
    Country: France

    International audience

  • Publication . Conference object . 2017
    Open Access English
    Authors: 
    Oscar Alvear; Nicola Roberto Zema; Enrico Natalizio; Carlos T. Calafate;
    Publisher: HAL CCSD
    Country: France
    Project: ANR | SUPER (ANR-11-IDEX-0004)

    Due to their deployment flexibility, Unmanned Aerial Vehicles have been found suitable for many application areas, one of them being air pollution monitoring. In fact, deploying a fleet of Unmanned Aerial Vehicles (UAVs) and using them to take environmental samples is an approach that has the potential to become one of the key enabling technologies to enforce pollution control in industrial or rural areas. In this paper, we propose to use an algorithm called Pollution-driven UAV Control (PdUC) that is based on a chemotaxis metaheuristic and a Particle Swarm Optimization (PSO) scheme that only uses local information. Our approach will be used by a monitoring Unmanned Aerial Vehicle to swiftly cover an area and map the distribution of its aerial pollution. We show that, when using PdUC, an implicit priority is applied in the construction of pollution maps, by focusing on areas where the pollutants' concentration is higher. In this way, accurate maps can be constructed in a faster manner when compared to other strategies. We compare PdUC against various standard mobility models through simulation, showing that our protocol achieves better performances, by finding the most polluted areas with more accuracy, within the time bounds defined by the UAV flight time.

  • English
    Authors: 
    Sergey Krivenko; Vladimir V. Lukin; Benoit Vozel; Kacem Chehdi;
    Publisher: HAL CCSD
    Country: France

    This paper describes a simple and fast way to predict efficiency of DCT-based filtering of images corrupted by signal dependent noise as this often happens for hyperspectral and radar remote sensing. Such prediction allows deciding in automatic way is it worth applying denoising to a given image under condition that parameters of signal-dependent noise are known a priori or pre-estimated with appropriate accuracy. It is shown that denoising efficiency can be predicted not only in terms of traditional quality criteria as output MSE or PSNR but also, with slightly less accuracy, in terms of visual quality metrics and PSNR-HVS-M.

  • Open Access English
    Authors: 
    Chignier-Riboulon Franck; Mauricette Fournier;
    Publisher: HAL CCSD
    Country: France

    International audience; Marvejols is a small town located in Lozère (France). Traditionally, the region was poor with an agricultural oriented economy. However, by the 1960s a new type of business was launched: the residential care facilities for disabled people, especially in relation to Jacques Blanc, a key person in the organization and development of this business. This economic activity brought jobs and new attractiveness, counterbalancing decline in traditional sectors. Nevertheless, currently, situation is less favourable, and the local players try to find out a new strategy, particularly in relation to diversification. In this study, our main aim was to understand conditions of starting and growing of this business. Moreover, we would like to understand current fragilities and attempts to adapt the economy of the territory. In this way, our students and we have chosen this area in relation to the economic and historical weight of its activity. The organization of field trips and survey was conducted in a comprehensive approach perspective. Therefore, we took account parameters working in this territory, such as strategies, psychologies (individual and collective), networks and identities. Human dimensions are strong, especially in discourses, and our main result is a better understanding of the local situation, with comparisons to close cases (Corrèze, Creuse). Furthermore, the quality of the geographical analysis provides working relations with the stakeholders

  • 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

  • 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 English
    Authors: 
    Fergal Martin-Tricot; Cédric Eichler; Pascal Berthomé;
    Publisher: HAL CCSD
    Country: France

    International audience; Industry includes more and more IoT components to have a better control on production and logistic processes. Unfortunately, growing network openness in a formerly isolated world induces major security risks which are especially critical in an industrial context. These risks are exacerbated by the highly fragmented nature of the industrial IoT market which imposes interoperability management and challenges security. We propose an approach to enable end-to-end data security within a heterogeneous IoT deployment. Interoperability is ensured by a central network powered by oneM2M interacting with various tier protocols. In this paper, we focus on secure communication with ZigBee and discuss how it can be transposed to other protocols, namely Z-Wave and Thread.

  • English
    Authors: 
    Frederic Rey; Nicolas Sinoir; C. Mazollier; Véronique Chable;
    Publisher: HAL CCSD
    Country: France

    All organic agricultural systems suffer from a lack of plant cultivars adapted to organic production. Within the framework of the European project SOLIBAM (Strategies for Organic and Low Input Breeding and Management) a study was undertaken to determine which cultivars farmers grow, why they grow them, and the expectations in plant breeding of organic stakeholders. A comprehensive range of investigations carried out between 2010 and 2012 provided information on the state of organic seed in France. Results fit with the hypothesis that the market is a significant factor influencing the choice of seeds and cultivars (local cultivars, landraces, modern cultivars). Expectations and practices of producers selling on a local market (i.e., direct sale) differ radically from those of producers selling to long food supply chains. This study shows that the availability and use of organic seeds have significantly improved over the last three years. A vast majority of organic producers willingly use organic seeds, with, on average, 45-70% (cereals) and 75%-100% (vegetables) of organic seeds being planted on farms. However, the total number of derogations remains quite high: there is still space for improvement in organic seed use and supply in France. Several limiting factors and levers were identified during the study, as well as farmers' expectations for the future on horticultural crops. The case study on tomatoes states the differences between producers selling on a local market and those of producers selling in long food supply chains regarding their practices (open field vs greenhouses) and the kind of cultivar they use or wish to have.

  • Publication . Part of book or chapter of book . Conference object . 2015
    Open Access English
    Authors: 
    Wenhua Zhu; Dexian Wang; Benoît Eynard; Matthieu Bricogne; Sébastien Remy;
    Publisher: HAL CCSD
    Country: France

    Part 4: Building Information Modeling (BIM); International audience; Large-scale 3D city building models have been widely used in urban planning, intelligent transportation, military simulation and other fields. The traditional ways of modeling generally have common problems such as low efficiency, waste of manpower and time consumption. How to find a rapid approach to automatically complete large-scale 3D modeling is a very hot research topic. In this paper we propose a novel approach of procedural modeling of buildings with CityEngine, which is combined with ArcGIS technology for the geographic information. This approach produces extensive architectural 3D models with high visual quality and geometric details at low cost. It includes following two contents concretely. At first, directly writing computer generated architecture (CGA) shape grammar to complete procedural modeling of building and other objects. Secondly, using facade modeling based on two-dimensional images to generate architectural model as well as creating high geometry details. It is validated that this novel approach of procedural modeling is a significant step forward that reduces a lot of modeling times by CGA shape grammars.

  • Closed Access English
    Authors: 
    Pau Prats-Iraola; Matteo Nannini; Nestor Yague-Martinez; Muriel Pinheiro; Jun-Su Kim; Francesco Vecchioli; Federico Minati; Mario Costantini; Sven Borgstrom; Prospero De Martino; +3 more
    Publisher: HAL CCSD
    Countries: France, Germany

    The contribution focuses on the current status of the ESA study entitled “InSARAP Sentinel-1 Constellation Study”, which investigates the interferometric performance of the S1A/S1B units. General aspects like the interferometric compatibility in terms of common range and Doppler bandwidth and the burst synchronization are addressed. Besides the first interferometric results with both units, time series results over the pilot sites combining both satellites are also shown, as well as some investigations with fast moving (i.e., glaciers) scenarios.

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