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1. Time-Delay Estimation Using ESPRIT With Extended Improved Spatial Smoothing Techniques for Radar Signals

Author

Nicolas Pinel, Yide Wang, Meng Sun, Cedric Le Bastard, Institut d'Électronique et des Technologies du numéRique (IETR), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet ENDSUM (Cerema Equipe-projet ENDSUM), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), ALYOTECH TS&I, ALYOTECH, 201306150010, China Scholarship Council, Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), and Université de Nantes (UN)-Université de Rennes 1 (UR1)

Subjects
Electromagnetic field, Computer science, 0211 other engineering and technologies, 02 engineering and technology, Signal, Measure (mathematics), law.invention, [SPI]Engineering Sciences [physics], propagator method (PM), law, 0202 electrical engineering, electronic engineering, information engineering, Time-delay estimation (TDE), Electrical and Electronic Engineering, Radar, ComputingMilieux_MISCELLANEOUS, 021101 geological & geomatics engineering, Remote sensing, high resolution, Propagator, 020206 networking & telecommunications, Geotechnical Engineering and Engineering Geology, Continuous-wave radar, improved spatial smoothing (ISS), Algorithm, Rotation (mathematics), Smoothing
Abstract

In the electromagnetic field, radar is widely used to measure or estimate the media parameters or to detect targets through obstructions. For horizontally stratified media, the layer thickness can be deduced from the time delays of backscattered echoes and the dielectric constants. The high-resolution method estimation of signal parameters via rotation invariance techniques (ESPRIT) has been proposed for time-delay estimation. In practice with a radar, backscattered echoes are correlated. In order to apply the ESPRIT method, in this letter, we propose to use two adaptive improved spatial smoothing techniques with the propagator method for fighting against the correlation between the echoes. The proposed solution does not use any approximation. Numerical examples are provided to show the performance of the algorithm.

Published
2016
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2. Polarized infrared reflectivity of 2D sea surfaces with two surface reflections

Author

Christophe Bourlier, Nicolas Pinel, Hongkun Li, Institut d'Électronique et des Technologies du numéRique (IETR), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), ALYOTECH TS&I, ALYOTECH, Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)

Subjects
Sea surface, Materials science, business.industry, Surface reflections, Infrared reflectivity, Soil Science, Geology, Energy conservation, Polarization (waves), 7. Clean energy, Reflectivity, Optics, 14. Life underwater, Computers in Earth Sciences, business, Remote sensing
Abstract

International audience; Sea surface infrared reflectivity is an important parameter in oceanic remote sensing. Most analytical models consider single surface reflections, and the polarization is usually ignored. However, a loss of energy is reported for large observation angles (θ > 50°) because multiple surface reflections are ignored. This article generalizes the infrared reflectivity derivation of Li et al. (Appl. Opt., Vol. 52, 6100-6111, 2013) for 1D surfaces (2D problems) to 2D surfaces (3D problems), so that the cross-polarization effect can be taken into account. The contributions of one and two successive surface reflections are analyzed separately. The bidirectional reflectivity and the hemispherical reflectivity are studied. It is shown that the sea surface infrared reflectivity is significant for large incidence and observation angles. The energy conservation criterion is then checked. The loss of energy is largely reduced after taking into account two surface reflections.

Published
2014
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3. IMP: a pipeline for reproducible reference-independent integrated metagenomic and metatranscriptomic analyses

Author

Anne Kaysen, Patrick May, Shaman Narayanasamy, Anna Heintz-Buschart, Paul Wilmes, Cedric Christian Laczny, Yohan Jarosz, Nicolás Pinel, Malte Herold, Emilie E. L. Muller, Luxembourg Centre For Systems Biomedicine (LCSB), University of Luxembourg [Luxembourg], ALYOTECH TS&I, ALYOTECH, Universidad EAFIT. Departamento de Ciencias, Biodiversidad, Evolución y Conservación, Fonds National de la Recherche - FnR [sponsor], and Luxembourg Centre for Systems Biomedicine (LCSB): Eco-Systems Biology (Wilmes Group) [research center]

Subjects
0301 basic medicine, Microbiologie [F11] [Sciences du vivant], Biotechnologie [F06] [Sciences du vivant], integration, computer.software_genre, Workflow, Microbial ecology, Multidisciplinaire, généralités & autres [F99] [Sciences du vivant], Microbial, 0302 clinical medicine, Biotechnology [F06] [Life sciences], Preprocessor, Microbiology [F11] [Life sciences], MIT License, ComputingMilieux_MISCELLANEOUS, Metatranscriptomics, computer.programming_language, Multi-omics, Microbiota, Genomic signature, Genomics, [SDV.BIBS]Life Sciences [q-bio]/Quantitative Methods [q-bio.QM], Reproducibility, data, Data mining, ecology, Algorithms, Data integration, Environmental sciences & ecology [F08] [Life sciences], High-throughput, Multidisciplinary, general & others [F99] [Life sciences], Computational biology, Biology, 03 medical and health sciences, [SDV.BBM.GTP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Genomics [q-bio.GN], Computational Biology, Python (programming language), Pipeline (software), Multi-omics data integration, Sciences de l'environnement & écologie [F08] [Sciences du vivant], 030104 developmental biology, Metagenomics, Metagenome, Microbiome, Transcriptome, computer, Software, 030217 neurology & neurosurgery
Abstract

Existing workflows for the analysis of multi-omic microbiome datasets are lab-specific and often result in sub-optimal data usage. Here we present IMP, a reproducible and modular pipeline for the integrated and reference-independent analysis of coupled metagenomic and metatranscriptomic data. IMP incorporates robust read preprocessing, iterative co-assembly, analyses of microbial community structure and function, automated binning, as well as genomic signature-based visualizations. The IMP-based data integration strategy enhances data usage, output volume, and output quality as demonstrated using relevant use-cases. Finally, IMP is encapsulated within a user-friendly implementation using Python and Docker. IMP is available at http://r3lab.uni.lu/web/imp/ (MIT license). Electronic supplementary material The online version of this article (doi:10.1186/s13059-016-1116-8) contains supplementary material, which is available to authorized users.

Published
2016
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4. Microwave Non‐Destructive Testing of Non‐Dispersive and Dispersive Media Using High‐Resolution Methods

Author

Khaled Chahine, Yide Wang, Nicolas Pinel, Christophe Bourlier, Vincent Baltazart, Xavier Derobert, Cedric Le Bastard, Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet ENDSUM (Cerema Equipe-projet ENDSUM), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), Lebanese International University (LIU), Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), ALYOTECH TS&I, ALYOTECH, Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), and Université de Nantes (UN)-Université de Rennes 1 (UR1)

Subjects
Engineering, Dominant wavelength, business.industry, Acoustics, Resolution (electron density), 0211 other engineering and technologies, Measure (physics), 020206 networking & telecommunications, dispersive media, 02 engineering and technology, high‐resolution signal processing methods, non‐dispersive media, Data modeling, [SPI]Engineering Sciences [physics], Nondestructive testing, Ground-penetrating radar, 0202 electrical engineering, electronic engineering, information engineering, Electronic engineering, Antenna (radio), business, ground penetrating radar, civil engineering, Microwave, 021101 geological & geomatics engineering
Abstract

International audience; This chapter discusses the principle and application of two model‐based algorithms for processing non‐dispersive and dispersive ground penetrating radar (GPR) data over layered medium under monostatic antenna configuration. Both algorithms have been selected for their super‐time resolution capability and reduced computational burden; they allow GPR to measure a layer thickness smaller than the fraction of the dominant wavelength. For non‐dispersive data, the ESPRIT algorithm is generalized to handle different kinds of data models encountered in experiments and in the literature. For dispersive data, the proposed adaptation of the MPM algorithm allows recovering the full‐time resolution and jointly estimating the time delays and quality factors of a layered medium with reduced bias. Both processing techniques are applied to probe‐layered roadways for NDT&E purposes.

Published
2016
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5. Road surface layers geometric parameters estimation by GPR using ESPRIT method

Author

Sun, Meng, Le Bastard, Cédric, Pinel, Nicolas, Wang, Yide, Li, Jianzhong, Institut d'Électronique et des Technologies du numéRique (IETR), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet ENDSUM (Cerema Equipe-projet ENDSUM), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), ALYOTECH TS&I, ALYOTECH, Southern University of Science and Technology [Shenzhen] (SUSTech), 201306150010, China Scholarship Council, Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), and Southern University of Science and Technology (SUSTech)

Subjects
interface roughness, [SPI]Engineering Sciences [physics], high resolution, road survey, time-delay estimation, propagator, ground penetrating radar
Abstract

International audience; In civil engineering, ground penetrating radar is widely used to assess theroadway structures. This paper evaluates the influence of interface roughness(surface and interlayer). A modified ESPRIT algorithm is proposed with aspectral smoothing technique for efficiently estimating the time delay, thepermittivity of the layers and the interface roughness. In order to reduce theimpact of noise, a preprocessing method called propagator is used to estimatethe noise variance. The algorithm is tested on simulated data obtainedby the rigorous numerical method called PILE (propagation inside layer expansion).Numerical simulations are conducted to assess the performance ofthe algorithm. The simulation results show that the proposed algorithm can estimate road parameters with small relative root mean square error.

Published
2016
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6. Comparative integrated omics: identification of key functionalities in microbial community-wide metabolic networks

Author

Jarosz, Yohan, Herold, Malte, Kaysen, Anne, Pinel, Nicolas, Roume, Hugo, Heintz-Buschart, Anna, Muller, Emilie, May, Patrick, Satagopam, Venkata, Laczny, Cédric, Narayanasamy, Shaman, Lebrun, Laura, Hoopmann, Michael, Schupp, James, Gillece, John, Hicks, Nathan, Engelthaler, David, Sauter, Thomas, Keim, Paul, Moritz, Robert, Wilmes, Paul, ALYOTECH TS&I, ALYOTECH, Luxembourg Centre For Systems Biomedicine (LCSB), University of Luxembourg [Luxembourg], European Molecular Biology Laboratory, Structural and Computational Biology Unit, Heidelberg, Germany, Université du Luxembourg (Uni.lu), Center for Microbial Genetics and Genomics, Northern Arizona University [Flagstaff], Section des Sciences de la Terre, and University of Geneva [Switzerland]

Subjects
[SDV.EE]Life Sciences [q-bio]/Ecology, environment, 0303 health sciences, 030306 microbiology, Community structure, [SDV.BBM.MN]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular Networks [q-bio.MN], Computational biology, 15. Life on land, Biology, Applied Microbiology and Biotechnology, Microbiology, Article, 6. Clean water, Transcriptome, 03 medical and health sciences, Metagenomics, [SDV.BBM.GTP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Genomics [q-bio.GN], Metaproteomics, Identification (biology), [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Keystone species, Gene, Function (biology), ComputingMilieux_MISCELLANEOUS, 030304 developmental biology, Biotechnology
Abstract

Mixed microbial communities underpin important biotechnological processes such as biological wastewater treatment (BWWT). A detailed knowledge of community structure and function relationships is essential for ultimately driving these systems towards desired outcomes, e.g., the enrichment in organisms capable of accumulating valuable resources during BWWT. A comparative integrated omic analysis including metagenomics, metatranscriptomics and metaproteomics was carried out to elucidate functional differences between seasonally distinct oleaginous mixed microbial communities (OMMCs) sampled from an anoxic BWWT tank. A computational framework for the reconstruction of community-wide metabolic networks from multi-omic data was developed. These provide an overview of the functional capabilities by incorporating gene copy, transcript and protein abundances. To identify functional genes, which have a disproportionately important role in community function, we define a high relative gene expression and a high betweenness centrality relative to node degree as gene-centric and network topological features, respectively. Genes exhibiting high expression relative to gene copy abundance include genes involved in glycerolipid metabolism, particularly triacylglycerol lipase, encoded by known lipid accumulating populations, e.g., Candidatus Microthrix parvicella. Genes with a high relative gene expression and topologically important positions in the network include genes involved in nitrogen metabolism and fatty acid biosynthesis, encoded by Nitrosomonas spp. and Rhodococcus spp. Such genes may be regarded as ‘keystone genes’ as they are likely to be encoded by keystone species. The linking of key functionalities to community members through integrated omics opens up exciting possibilities for devising prediction and control strategies for microbial communities in the future. Charting metabolic activity in diverse microbial communities could help scientists control the behavior of these communities, new research shows. Paul Wilmes and colleagues at the University of Luxembourg, alongside scientists from the United States, set out to characterize the biological function of bacterial communities—normally a daunting task due to the sheer number of species involved. To accomplish this, Wilmes and colleagues took a community-wide approach, collecting genomic, transcriptomic and proteomic data from lipid-accumulating microbial consortia in a wastewater treatment tank and assembling functional maps reflecting overall biochemical processes. The scientists were then able to identify ‘keystone’ genes that play a critical role in the community—for example, genes involved in fatty acid biosynthesis were particularly prominent. Such findings could guide strategies for manipulating microbial communities for optimized disease control or biofuel production in future.

Published
2015
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7. Radar LGA scattering above a sea surface in a stratified medium solved by physical optics

Author

Christophe Bourlier, Dusan Cvetkovic, Nicolas Pinel, Institut d'Électronique et des Technologies du numéRique (IETR), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), ALYOTECH TS&I, ALYOTECH, Projet PRORASEM (DGA RAPID DGCIS convention n°122906200), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Scattering, business.industry, Physical optics, Microwave radar, law.invention, Computational physics, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, Optics, law, Surface wave, Surface roughness, Duct (flow), 14. Life underwater, Radar, business, Refractive index
Abstract

International audience; Propagation and low grazing angle (LGA) scattering of centimetre-scale electromagnetic waves in a marine environment is thesubject of scientific research for decades. For such a problem, a duct, which is described by the variations of the refractiveindex profile with the altitude near the sea surface, can substantially affect the performance of a radar system. This is a jointproblem of propagation and scattering, especially for low grazing angles. To solve it, the well-known Parabolic Wave Equation(PWE) method, combined with the Split-Step Fourier resolution technique (SSF) [1], is commonly used. This fast method canbe applied for any refractive index profile, but its main drawback is the use of heuristic boundary conditions. In this article,an alternative method, based on the Physical Optics (PO) approximation to derive the boundary conditions, is developed.Moreover, this method will be validated by a rigorous method based on the solution of Boundary Integral Equations (BIE) [2]solved by the Method of Moments (MoM) and accelerated by the Forward-Backward (FB) method.

Published
2015
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8. Diffusion microondes cohérente par une surface de mer dans un milieu stratifié par une approche asymptotique

Author

Cvetkovic, Dusan, Bourlier, Christophe, Pinel, Nicolas, Institut d'Électronique et des Technologies du numéRique (IETR), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), ALYOTECH TS&I, ALYOTECH, Projet PRORASEM (DGA RAPID DGCIS convention n°122906200), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Université de Nantes (UN)-Université de Rennes 1 (UR1), and Charlier, Sandrine

Subjects
[SPI]Engineering Sciences [physics], [SPI] Engineering Sciences [physics]
Abstract

National audience; Cette communication pr´esente le champ diffusé par unesurface de mer rugueuse calculé par l’approximation de l’optiquephysique (OP). De plus, pour tenir compte de l’effet de conduitau-dessus de la surface de mer, l’indice de réfraction n’est pasconsidéré comme constant en fonction de la hauteur mais suitune loi affine. Ainsi, pour résoudre conjointement le problème dediffraction et de propagation, tout d’abord le champ est propagéà l’aide de la fonction de Green associée à l’indice de réfraction,puis l’OP est itérée pour calculer la contribution du champdiffracté associé à chacun des rebonds. L’approche est alorsvalidée par une méthode de référence basée sur la méthode desmoments. De plus, avec l’OP, le coefficient de diffusion cohérentest calculé analytiquement, permettant ainsi de généraliser lecoefficient de réflexion d’Ament à n rebonds. Ce coefficient estcouramment appliqué dans une méthode de type “ParabolicWaveEquation (PWE)” et résolue par un schéma de type “Split StepFourier (SSF)” pour prendre en compte l’effet de la rugosité dela surface.

Published
2015

9. Propagation Radar au-dessus d'une surface de mer rugueuse dans un milieu stratifié avec l'optique physique

Author

Cvetkovic, Dusan, Bourlier, Christophe, Pinel, Nicolas, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), ALYOTECH TS&I, ALYOTECH, DGA RAPID DGCIS n°122906200 - Projet PRORASEM 'Propagation et diffusion des ondes électromagnétiques sur des surfaces naturelles en présence d'un objet, y compris aux incidences très rasantes : optimisation et réduction du temps de calcul'., Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Nantes Université (NU)-Université de Rennes 1 (UR1), and Charlier, Sandrine

Subjects
[SPI]Engineering Sciences [physics], [SPI] Engineering Sciences [physics]
Abstract

National audience; Cet article présente une méthode haute fréquence, basée sur l’approximation de l’Optique Physique (OP), pour évaluer les courants sur une surface de mer rugueuse parfaitement conductrice dans le domaine Radar des microondes. Ainsi, à partir de la connaissance de la fonctionde Green du conduit (milieu stratifié décrit par un modèle linéaire du profil d’indice de réfraction au carré) présent au-dessus de la mer, ces courants sont rayonnés à l’aide du principe d’Huygens pour calculer le champ diffusé dans le conduit. A cause du phénomène de réfraction,ce champ va produire un courant sur la surface (second rebond) qui est à nouveau évalué par l’OP. Ce processus est ainsi réitéré. De plus, cette méthode sera validée avec une méthode rigoureuse basée sur la méthode des moments et accélérée par la Forward-Backward.

Published
2015

10. Time delay and interface roughness estimation by GPR for pavement survey

Author

Amine Ihamouten, Yide Wang, Meng Sun, Vincent Baltazart, Cedric Le Bastard, Nicolas Pinel, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), ALYOTECH TS&I, ALYOTECH, Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet ENDSUM (Cerema Equipe-projet ENDSUM), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), Structure et Instrumentation Intégrée (IFSTTAR/COSYS/SII), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-PRES Université Nantes Angers Le Mans (UNAM), Département Mesure, Auscultation et Calcul Scientifique (IFSTTAR/MACS), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)

Subjects
Data processing, ground penetrating radar (GPR), sensitivity analysis, Acoustics, Interface (computing), Mineralogy, Surface finish, method of moments (MoM), law.invention, MUSIC, [SPI.TRON]Engineering Sciences [physics]/Electronics, interface roughness, [SPI]Engineering Sciences [physics], Geophysics, Approximation error, law, Distortion, Ground-penetrating radar, Radar, pavement survey, Pile, Geology, time-delay estimation (TDE)
Abstract

International audience; In civil engineering, ground-penetrating radar is widely used for road pavement survey. In contrast to the existing literature, this paper takes account of the influence of interface roughness (surface and interlayer roughness) within the scope of the data processing of radar signals. The rigorous electromagnetic method PILE (propagation inside layer expansion) provides the simulated data that show the influence of the interface roughness on the backscattered primary echoes of stratified media, the interface roughness provides a continuous frequency decay of the magnitude of the echoes. The observed frequency variations of the radar magnitude introduce some shape distortion on the radar waveform. The latter variations can be modelled by exponential function, which provides satisfactory results for a narrow bandwidth (2 GHz). An adaptation of the root-MUSIC algorithm is proposed. As a result, it is allowed to jointly estimate the time delay and the interface roughness. Then, the algorithm is tested on the data simulated by the PILE method, and numerical examples are provided to assess the performance of this algorithm. The associated results show that the proposed algorithm can estimate both the time delay and roughness parameters with a small relative error.

Published
2015
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11. Low-grazing angle propagation and scattering above the sea surface in the presence of a duct jointly solved by boundary integral equations

Author

Christophe Bourlier, Hongkun Li, Nicolas Pinel, Institut d'Électronique et des Technologies du numéRique (IETR), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), ALYOTECH TS&I, ALYOTECH, French ministry of the Redressement Productif Direction Generale de la Competitivite de lIndustrie et des Services and the French ministry of defense DGA in the framework of the PRORASEM project in cooperation between ONERA ALYOTECH and UNAN-IETR, Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), and Université de Nantes (UN)-Université de Rennes 1 (UR1)

Subjects
Physics, Electromagnetic scattering by rough surfaces, Discretization, Nonhomogeneous media, Scattering, Linear system, Mathematical analysis, 020206 networking & telecommunications, 02 engineering and technology, Refractive index profile, 01 natural sciences, Integral equation, 010309 optics, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, Classical mechanics, electromagnetic scattering, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Surface roughness, Computational electromagnetics, Electrical and Electronic Engineering, Propagation, Refractive index, ComputingMilieux_MISCELLANEOUS
Abstract

For a two-dimensional problem and at microwave radar frequencies, this paper presents a method to compute the field scattered by a highly conducting (the impedance boundary condition is applied) rough sea surface in the presence of a duct having a linear-square refractive index profile below a medium of constant refractive index. In a previous paper, the corresponding Green's function, which allows us to solve the propagation problem, has been derived without considering the sea surface. Using the boundary integral equation (BIE) method, this paper solves jointly the scattering problem from the sea surface and the propagation problem by including this Green's function in the BIE. In addition, to efficiently solve the linear system obtained from the method of moments by discretizing the integral equations, the forward-backward method is applied, which allows us to consider very long rough surfaces.

Published
2015
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12. Road parameters estimation By GPR using ESPRIT method

Author

Sun, Meng, Wang, Yide, Li, Jianzhong, Le Bastard, Cédric, Pinel, Nicolas, Charlier, Sandrine, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Sino-French Research Center in Information and Communication (SFC/RIC), Université de Nantes (UN)-Southern University of Science and Technology (SUSTech), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet ENDSUM (Cerema Equipe-projet ENDSUM), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), ALYOTECH TS&I, ALYOTECH, Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-CentraleSupélec-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES), Université de Nantes (UN)-Southern University of Science and Technology [Shenzhen] (SUSTech), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, [SPI.SIGNAL] Engineering Sciences [physics]/Signal and Image processing
Abstract

International audience; In civil engineering, ground penetrating radar is widely used for road pavement surveys. The layer thickness is deduced from both the time delays of the backscattered echoes and the permittivity of the layers. In this paper, the influence of the interface roughness is studied. A modified ESPRIT algorithm is proposed for estimating the time delay, the interface roughness and the permittivity of layers from the received echoes. The algorithm is tested on simulated data obtained from the propagation inside layer expansion (PILE) method. Numerical examples are provided to demonstrate the performance of the algorithm.

Published
2015

13. Community-integrated omics links dominance of a microbial generalist to fine-tuned resource usage

Author

James M. Schupp, Shaman Narayanasamy, Anna Heintz-Buschart, Linda Wampach, Nitin S. Baliga, John D. Gillece, Robert L. Moritz, Cindy M. Liu, Michael R. Hoopmann, Paul Wilmes, Cedric Christian Laczny, Laura Lebrun, Nicolás Pinel, Cédric Guignard, Nikos Vlassis, Patrick May, Lance B. Price, Emilie E. L. Muller, Jake Lin, Nathan D. Hicks, Hugo Roume, Paul Keim, ALYOTECH TS&I, ALYOTECH, Luxembourg Centre For Systems Biomedicine (LCSB), University of Luxembourg [Luxembourg], Environment and Agro-Biotechnologies, Centre de Recherche Public - Gabriel Lippmann (LUXEMBOURG), Instituut voor Informatica (IvI), Universiteit van Amsterdam (UvA), Section des Sciences de la Terre, University of Geneva [Switzerland], Center for Microbial Genetics and Genomics, Northern Arizona University [Flagstaff], Luxembourg Centre for Systems Biomedicine (LCSB): Eco-Systems Biology (Wilmes Group) [research center], Luxembourg Centre for Systems Biomedicine (LCSB): Bioinformatics Core (R. Schneider Group) [research center], University of Luxembourg: High Performance Computing - ULHPC [research center], and Luxembourg Centre for Systems Biomedicine (LCSB): Machine Learning (Vlassis Group) [research center]

Subjects
Proteomics, Environmental sciences & ecology [F08] [Life sciences], Microbiologie [F11] [Sciences du vivant], Niche, Population, General Physics and Astronomy, Genomics, Biology, Wastewater, Generalist and specialist species, General Biochemistry, Genetics and Molecular Biology, Article, Metabolomics, Bacterial Proteins, [SDV.BBM.GTP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Genomics [q-bio.GN], Dominance (ecology), Ecosystem, Microbiology [F11] [Life sciences], education, ComputingMilieux_MISCELLANEOUS, Ecological niche, education.field_of_study, Multidisciplinary, Bacteria, Ecology, General Chemistry, 15. Life on land, [SDV.BIBS]Life Sciences [q-bio]/Quantitative Methods [q-bio.QM], 6. Clean water, Sciences de l'environnement & écologie [F08] [Sciences du vivant], Genetics & genetic processes [F10] [Life sciences], [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Génétique & processus génétiques [F10] [Sciences du vivant]
Abstract

Microbial communities are complex and dynamic systems that are primarily structured according to their members’ ecological niches. To investigate how niche breadth (generalist versus specialist lifestyle strategies) relates to ecological success, we develop and apply an integrative workflow for the multi-omic analysis of oleaginous mixed microbial communities from a biological wastewater treatment plant. Time- and space-resolved coupled metabolomic and taxonomic analyses demonstrate that the community-wide lipid accumulation phenotype is associated with the dominance of the generalist bacterium Candidatus Microthrix spp. By integrating population-level genomic reconstructions (reflecting fundamental niches) with transcriptomic and proteomic data (realised niches), we identify finely tuned gene expression governing resource usage by Candidatus Microthrix parvicella over time. Moreover, our results indicate that the fluctuating environmental conditions constrain the accumulation of genetic variation in Candidatus Microthrix parvicella likely due to fitness trade-offs. Based on our observations, niche breadth has to be considered as an important factor for understanding the evolutionary processes governing (microbial) population sizes and structures in situ., Within microbial communities, microorganisms adopt different lifestyle strategies to use the available resources. Here, the authors use an integrated ‘multi-omic’ approach to study niche breadth (generalist versus specialist lifestyles) in oleaginous microbial assemblages from an anoxic wastewater treatment tank.

Published
2014
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14. Monostatic Radar time response for the electromagnetic scattering from a measured rough surface

Author

C. Chanel, C. Bourlier, N. Pinel, C. Carel, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), ALYOTECH TS&I, ALYOTECH, THALES COMMUNICATIONS & SECURITY, THALES, Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), THALES [France], Charlier, Sandrine, and Nantes Université (NU)-Université de Rennes 1 (UR1)

Subjects
Electromagnetic field, Physics, Scattering, business.industry, 0211 other engineering and technologies, 02 engineering and technology, 15. Life on land, Method of moments (statistics), Physics::Classical Physics, 01 natural sciences, 010309 optics, Bistatic radar, Optics, Surface wave, 0103 physical sciences, Surface roughness, Profilometer, Barker code, business, 021101 geological & geomatics engineering
Abstract

International audience; This paper computes the monostatic Radar frequency and time responses of the electromagnetic field scattered by a 1D profile of a natural soil. The rough surface profile was measured with a profilometer which uses a stylus to measure the variations of the heights on the ground of a fallow land. Then, from this experimental surface, the electromagnetic response is calculated from the rigorous Method of Moments (MoM) for moderate incidence angles and by considering a Barker code as the input signal.

Published
2014

15. Statistical analysis of Real Aperture Radar field backscattered from sea surfaces under moderate winds by Monte-Carlo simulations

Author

Antoine Ghaleb, Nicolas Pinel, Christophe Bourlier, Bertrand Chapron, Nicole de Beaucoudrey, Rene Garello, ALYOTECH TS&I, ALYOTECH, Laboratoire d'Océanographie Spatiale (LOS), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Lab-STICC_TB_CID_TOMS, Laboratoire des sciences et techniques de l'information, de la communication et de la connaissance (Lab-STICC), École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Télécom Bretagne-Institut Brestois du Numérique et des Mathématiques (IBNM), Université de Brest (UBO)-Université européenne de Bretagne - European University of Brittany (UEB)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Télécom Bretagne-Institut Brestois du Numérique et des Mathématiques (IBNM), Université de Brest (UBO)-Université européenne de Bretagne - European University of Brittany (UEB)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS), ARTAL, Projet MODENA, Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Université européenne de Bretagne - European University of Brittany (UEB)-École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Télécom Bretagne-Institut Brestois du Numérique et des Mathématiques (IBNM), Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université européenne de Bretagne - European University of Brittany (UEB)-École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Télécom Bretagne-Institut Brestois du Numérique et des Mathématiques (IBNM), and Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Uniform distribution (continuous), Rayleigh distribution, business.industry, Monte Carlo method, law.invention, Computational physics, statistical study, Radar engineering details, Optics, Amplitude, 24 sea surface electromagnetic (EM) scattering, law, Monte Carlo process, General Earth and Planetary Sciences, real aperture radar (RAR), Electrical and Electronic Engineering, Radar, business, Physics::Atmospheric and Oceanic Physics, Weibull distribution, K-distribution, sea surface electromagnetic (EM) scattering
Abstract

12 pages; International audience; The statistical properties of the electromagnetic field backscattered from sea surfaces are studied by using asymptotic numerical methods. Sea surfaces are modeled by using the Elfouhaily et al. spectrum model. The influence of the radar spatial resolution on the field statistics is studied for various wind conditions and radar configurations, by considering equal range and azimuth resolutions. It is observed that the backscattered field phase can be assimilated to a uniform distribution and that the amplitude resembles a Rayleigh distribution. Moreover, reducing the radar spatial resolution d induces a stronger variability of the backscattered field amplitude and a departure from the Rayleigh distribution. This departure is enhanced particularly when the radar look approaches the cross-wind direction and also when increasing the wind speed. Also, a fitting of the amplitude distribution with various theoretical statistical laws (gamma, Weibull, K, and so on) highlights the general good fitting of the K distribution, which is in agreement with previous work led from measurements.

Published
2014
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16. Full wave PILE method for the electromagnetic scattering from random rough layers

Author

C. Le Bastard, Christophe Bourlier, Nicolas Pinel, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet ENDSUM (Cerema Equipe-projet ENDSUM), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), ALYOTECH TS&I, ALYOTECH, Nantes Université (NU)-Université de Rennes 1 (UR1), Charlier, Sandrine, Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)

Subjects
Engineering, Ground wave propagation, [SPI] Engineering Sciences [physics], business.industry, Scattering, 0211 other engineering and technologies, 020206 networking & telecommunications, 02 engineering and technology, [SPI]Engineering Sciences [physics], Full wave, Optics, Ground-penetrating radar, 0202 electrical engineering, electronic engineering, information engineering, business, Pile, 021101 geological & geomatics engineering
Abstract

International audience; This paper presents the rigorous efficient PILE (Propagation Inside-Layer-Expansion) numerical method [1] to calculate the impulse response of the field scattered by three homogeneous media separated by two random rough surfaces. Here, the study is applied to ground penetrating radar (GPR) (nadir angle, Ricker pulse, near or/and far field) for nondestructive pavement survey by taking the roughness of the surfaces into account and by calculating the contribution of each echo coming from the multiple scattering inside the layer. The PILE method starts from the Method of Moments (MoM), and the impedance matrix is inverted by blocks from the Taylor series expansion of the inverse of the Schur complement. Its main use is that it is rigorous, with a simple formulation and has a straightforward physical interpretation. Actually, this last property relies on the fact that each block of the impedance matrix is linked to a particular and quasi-independent physical process occurring during the multiple scattering process between the two rough surfaces. Furthermore, the PILE method allows us to use any fast method developed for a single interface.

Published
2014

17. MOCEM V4 - radar simulation of ship at sea for SAR and ISAR applications

Author

Cochin, C., Louvigne, J.C., Fabbri, R., Le Barbu, Corentin, Ferro-Famil, Laurent, Knapskog, Atle-Onar, Ødegaard, Nina, DGA Maîtrise de l'information (DGA.MI), Direction générale de l'Armement (DGA), ALYOTECH TS&I, ALYOTECH, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Norwegian Defence Research Establishment (FFI), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), and Nantes Université (NU)-Université de Rennes 1 (UR1)

Subjects
[INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2014

18. Rigorous and asymptotic modelling of coherent scattering from random rough layers: application to roadways

Author

Pinel, Nicolas, Bourlier, Christophe, Le Bastard, Cédric, ALYOTECH TS&I, ALYOTECH, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet ENDSUM (Cerema Equipe-projet ENDSUM), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Nantes Université (NU)-Université de Rennes 1 (UR1), and Charlier, Sandrine

Subjects
[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, [SPI.SIGNAL] Engineering Sciences [physics]/Signal and Image processing
Abstract

International audience; This paper presents the rigorous efficient PILE (Propagation-Inside-Layer Expansion) numerical method and an extension of the Ament model to calculate the field scattered by three homogeneous media separated by two random rough surfaces. Here, the study is applied to ground penetrating radar (GPR) (nadir angle, wide band) for nondestructive survey by taking the roughness of the surfaces into account and by calculating the contribution of each echo coming from the multiple scattering inside the layer. The application to roadways is investigated.

Published
2014

19. Propagation des ondes radar au-dessus d'une surface de mer en incidence rasante : optimisation et réduction des temps de calcul

Author

Pinel, Nicolas, Noblet, Mathieu, Bourlier, Christophe, Fabbro, Vincent, ALYOTECH TS&I, ALYOTECH, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), ONERA - The French Aerospace Lab [Toulouse], ONERA, Financement DGA-DGCIS, Projet RAPID 'PRORASEM', Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Nantes Université (NU)-Université de Rennes 1 (UR1), and Charlier, Sandrine

Abstract

National audience; Cette étude relèvera le défi à la fois scientifique et technologique de mettre en œuvre une méthode innovante prenant en compte conjointement la diffraction par la surface de la mer et la propagation en milieu atmosphérique inhomogène, c'est-à-dire le conduit au-dessus de la surface.

Published
2014

20. Radar backscattering modeling of oil slicks at sea based on the Model of Local Balance

Author

Nicolas Pinel, Christophe Bourlier, Irina A. Sergievskaya, Charlier, Sandrine, ALYOTECH TS&I, ALYOTECH, Institut d'Électronique et des Technologies du numéRique (IETR), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Institute of Applied Physics of RAS, Russian Academy of Sciences [Moscow] (RAS), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)

Subjects
Balance (accounting), Meteorology, law, Environmental science, 14. Life underwater, Racing slick, Radar, ComputingMilieux_MISCELLANEOUS, Remote sensing, law.invention
Abstract

International audience

Published
2014

21. Rigorous and asymptotic models of coherent scattering from random rough layers with applications to roadways and geoscience

Author

Pinel, Nicolas, Bourlier, Christophe, Le Bastard, Cédric, Charlier, Sandrine, ALYOTECH TS&I, ALYOTECH, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet ENDSUM (Cerema Equipe-projet ENDSUM), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, [SPI.SIGNAL] Engineering Sciences [physics]/Signal and Image processing
Abstract

International audience; This paper presents the rigorous efficient PILE (Propagation-Inside-Layer Expansion) numerical method and an extension of the Ament model to calculate the field scattered by three homogeneous media separated by two random rough surfaces. Here, the study is applied to ground penetrating radar (GPR) (nadir angle, wide band) for nondestructive survey by taking the roughness of the surfaces into account and by calculating the contribution of each echo coming from the multiple scattering inside the layer. Applications to roadways and geoscience are investigated.

Published
2014

22. Modélisation asymptotique de la propagation et de la diffusion radar au-dessus d'une surface de mer en présence d'un conduit

Author

Cvetkovic, Dusan, Pinel, Nicolas, Bourlier, Christophe, Institut d'Électronique et des Technologies du numéRique (IETR), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), ALYOTECH TS&I, ALYOTECH, Université de Nantes (UN)-Université de Rennes 1 (UR1), Charlier, Sandrine, Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)

Abstract

National audience; Cet article présente une méthode asymptotique pour évaluer le champ diffusé par une surface de mer rugueuse en présence d'un conduit lorsque la surface est illuminée par un radar côtier en visée rasante. Pour la propagation, la méthode proposée est basée sur une approche rayon, alors que le problème de diffusion est résolue à l'aide du coefficient dit de Ament, dans lequel l'effet de l'ombrage dû à la rugosité de la surface est pris en compte. De plus, ce coefficient est modifié afin d'introduire le facteur de focalisation qui caractérise le fait que la densité de puissance portée par l'onde est modifiée dans le conduit.

Published
2013

23. Bridging the gap between the Babinet principle and the physical optics approximation: Vectorial problem

Author

Kubicke, Gildas, Bourlier, Christophe, Delahaye, Morgane, Corbel, Charlotte, Pinel, Nicolas, Pouliguen, Philippe, DGA Maîtrise de l'information (DGA.MI), Direction générale de l'Armement (DGA), Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), ALYOTECH TS&I, ALYOTECH, DGA Mission Recherche et Innovation Scientifique (DGA MRIS), DGA, Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), and Université de Nantes (UN)-Université de Rennes 1 (UR1)

Abstract

International audience; For a three-dimensional problem and by assuming perfectly electric conducting objects, this paper shows that the Babinet principle (BP) can be derived from the physical optics (PO) approximation. Indeed, following the same idea as Ufimtsev, from the PO approximation and in the far-field zone, the field scattered by an object can be split up into a field which mainly contributes around the specular direction (illuminated zone) and a field which mainly contributes around the forward direction shadowed zone), which is strongly related to the scattered field obtained from the BP. The only difference resides in the integration surface. We show athematically that the involved integral does not depend on the shape of the object but only on its contour. Simulations are provided to illustrate the link between BP and PO. The main gain of this work is that it provides a more complete physical insight into the connection between PO and BP.

Published
2013
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24. Electromagnetic wave scattering from random rough surfaces - Asymptotic models

Author

Nicolas Pinel, Christophe Bourlier, ALYOTECH TS&I, ALYOTECH, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Joseph Saillard, Charlier, Sandrine, Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), and Université de Nantes (UN)-Université de Rennes 1 (UR1)

Subjects
ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2013

25. Genome Sequence of 'Candidatus Microthrix parvicella' Bio17-1, a Long-Chain-Fatty-Acid-Accumulating Filamentous Actinobacterium from a Biological Wastewater Treatment Plant

Author

Emilie E. L. Muller, Paul Keim, Nitin S. Baliga, James M. Schupp, Valter Tandoi, Khai Luong, Jonas Korlach, David M. Engelthaler, Paul Wilmes, Nicolás Pinel, John D. Gillece, Lance B. Price, Caterina Levantesi, ALYOTECH TS&I, ALYOTECH, Pacific Biosciences [Menlo Park], Pacific Biosciences of California, Center for Microbial Genetics and Genomics, Northern Arizona University [Flagstaff], Luxembourg Centre For Systems Biomedicine (LCSB), University of Luxembourg [Luxembourg], and Luxembourg Centre for Systems Biomedicine (LCSB): Eco-Systems Biology (Wilmes Group) [research center]

Subjects
DNA, Bacterial, Environmental sciences & ecology [F08] [Life sciences], Microbiologie [F11] [Sciences du vivant], filamentous bacteria, Molecular Sequence Data, Wastewater, 010501 environmental sciences, 01 natural sciences, Microbiology, Actinobacteria, 03 medical and health sciences, [SDV.BBM.GTP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Genomics [q-bio.GN], Microthrix parvicella, bulkng, genoma, Botany, Microbiology [F11] [Life sciences], Molecular Biology, ComputingMilieux_MISCELLANEOUS, 030304 developmental biology, 0105 earth and related environmental sciences, Whole genome sequencing, 0303 health sciences, biology, Fatty Acids, Sequence Analysis, DNA, biochemical phenomena, metabolism, and nutrition, biology.organism_classification, 6. Clean water, Genome Announcements, Sciences de l'environnement & écologie [F08] [Sciences du vivant], Candidatus Microthrix, bacteria, Candidatus Microthrix parvicella, Sewage treatment, Genetics & genetic processes [F10] [Life sciences], Long chain fatty acid, Génétique & processus génétiques [F10] [Sciences du vivant], Genome, Bacterial, Bacteria
Abstract

“ Candidatus Microthrix” bacteria are deeply branching filamentous actinobacteria which occur at the water-air interface of biological wastewater treatment plants, where they are often responsible for foaming and bulking. Here, we report the first draft genome sequence of a strain from this genus: “ Candidatus Microthrix parvicella” strain Bio17-1.

Published
2012
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