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Computation of components' interfaces in highly complex assemblies

François Jourdes, Georges-Pierre Bonneau, Stefanie Hahmann, Jean-Claude Léon, François Faure
2014 Computer-Aided Design  
The preparation of CAD models from complex assemblies for simulation purposes is a very time-consuming and tedious process, since many tasks such as meshing and idealization are still completed manually. Herein, the detection and extraction of geometric interfaces between components of the assembly is of central importance not only for the simulation objectives but also for all necessary shape transformations such as idealizations or detail removals. It is a repetitive task in particular when
more » ... mplex assemblies have to be dealt with. This paper proposes a method to rapidly and fully automatically generate a precise geometric description of interfaces in generic B-Rep CAD models. The approach combines an efficient GPU ray-casting technique commonly used in computer graphics with a graph-based curve extraction algorithm. Not only is it able to detect a large number of interfaces efficiently, but it also provides an accurate Nurbs geometry of the interfaces, that can be stored in a plain STEP file [1] for further downstream treatment. We demonstrate our approach on examples from aeronautics and automotive industry.
doi:10.1016/j.cad.2013.08.029 fatcat:rmknrd5saffyxl3rpgjdlvjy6m

Stochastic Generator of Earthquakes for Mainland France

Corentin Gouache, Pierre Tinard, François Bonneau
2022 Applied Sciences  
Mainland France is characterized by low-to-moderate seismic activity, yet it is known that major earthquakes could strike this territory (e.g., Liguria in 1887 or Basel in 1356). Assessing this French seismic hazard is thus necessary in order to support building codes and to lead prevention actions towards the population. The Probabilistic Seismic Hazard Assessment (PSHA) is the classical approach used to estimate the seismic hazard. One way to apply PSHA is to generate synthetic earthquakes by
more » ... propagating information from past seismicity and building various seismic scenarios. In this paper, we present an implementation of a stochastic generator of earthquakes and discuss its relevance to mimic the seismicity of low-to-moderate seismic areas. The proposed stochastic generator produces independent events (main shocks) and their correlated seismicity (only aftershocks). Main shocks are simulated first in time and magnitude considering all available data in the area, and then localized in space with the use of a probability map and regionalization. Aftershocks are simulated around main shocks by considering both the seismic moment ratio and distribution of the aftershock's proportion. The generator is tested with mainland France data.
doi:10.3390/app12020571 fatcat:xuutsj5ilzhpblqneguzp2fdiu

A propos du dépérissement du pin portugais dans les landes

Maurice BONNEAU, J. GELPE, François LE TACON
1969 Revue Forestière Française  
GELPE François LE TACON Ingénieur du G . R . E . F . Ingénieur agronome Directeur de la Station Chargé de recherches Station de recherches a u C . N . R .  ...  la troisième ou quatrième ligne d'arbres, alors que, dans les parcelles-témoins, le regard porte très loin . 349 00 10 14 13 02 01 12 15 11 T T NK PK NPK NPK NPK NP NPK --Mn Mn BONNEAU  ... 
doi:10.4267/2042/20280 fatcat:6frhdsmn4ngyjoq3eqhl4hxpr4

A methodology for pseudo-genetic stochastic modeling of discrete fracture networks

François Bonneau, Vincent Henrion, Guillaume Caumon, Philippe Renard, Judith Sausse
2013 Computers & Geosciences  
Stochastic simulation of fracture systems is an interesting approach to build a set of dense and complex networks. However, discrete fracture models made of planar fractures generally fail to reproduce the complexity of natural networks, both in terms of geometry and connectivity. In this study a pseudogenetic method is developed to generate stochastic fracture models that are consistent with patterns observed on outcrops and fracture growth principles. The main idea is to simulate evolving
more » ... ture networks through geometric proxies by iteratively growing 3D fractures. The algorithm defines heuristic rules in order to mimic the mechanics of fracture initiation, propagation, interaction and termination. The growth process enhances the production of linking structure and impacts the connectivity of fracture networks. A sensitivity study is performed on synthetic examples. The method produces unbiased fracture dip and strike statistics and qualitatively reproduces the fracture density map. The fracture length distribution law is underestimated because of the early stop in fracture growth after intersection.
doi:10.1016/j.cageo.2013.02.004 fatcat:tswwedphnfbwbi6nsex4vltswi

Numerical modeling of the geothermal hydrology of the Volcanic Island of Basse-Terre, Guadeloupe

Margaux Raguenel, Thomas Driesner, François Bonneau
2019 Geothermal Energy  
doi:10.1186/s40517-019-0144-5 fatcat:tocpuu7jgjas7o2lybf62efsnm

RINGMesh: A programming library for developing mesh-based geomodeling applications

Jeanne Pellerin, Arnaud Botella, François Bonneau, Antoine Mazuyer, Benjamin Chauvin, Bruno Lévy, Guillaume Caumon
2017 Computers & Geosciences  
Bonneau, B. Chauvin), Total S.A. (J. Pellerin, A. Mazuyer), and Chevron (B. Chauvin).  ... 
doi:10.1016/j.cageo.2017.03.005 fatcat:v5gxehdmkvginb6zjtqdvnpcd4

Molecular screening of 980 cases of suspected hereditary optic neuropathy with a report on 77 novelOPA1mutations

Marc Ferré, Dominique Bonneau, Dan Milea, Arnaud Chevrollier, Christophe Verny, Hélène Dollfus, Carmen Ayuso, Sabine Defoort, Catherine Vignal, Xavier Zanlonghi, Jean-Francois Charlin, Josseline Kaplan (+5 others)
2009 Human Mutation  
Titre Molecular screening of 980 cases of suspected hereditary optic neuropathy with a report on 77 novel OPA1 mutations Type de publication Article de revue Auteur Ferré, Marc [1]
doi:10.1002/humu.21025 pmid:19319978 fatcat:2jzz7oabyvbtdbkxtceejfpt3q

Impact of Photosensitizers Activation on Intracellular Trafficking and Viscosity

Kelly Aubertin, Stéphanie Bonneau, Amanda K. A. Silva, Jean-Claude Bacri, François Gallet, Claire Wilhelm, Nikolai Lebedev
2013 PLoS ONE  
The intracellular microenvironment is essential for the efficiency of photo-induced therapies, as short-lived reactive oxygen species generated must diffuse through their intracellular surrounding medium to reach their cellular target. Here, by combining measurements of local cytoplasmic dissipation and active trafficking, we found that photosensitizers activation induced small changes in surrounding viscosity but a massive decrease in diffusion. These effects are the signature of a return to
more » ... ermodynamic equilibrium of the system after photo-activation and correlated with depolymerization of the microtubule network, as shown in a reconstituted system. These mechanical measurements were performed with two intracellular photosensitizing chlorins having similar quantum yield of singlet oxygen production but different intracellular localizations (cytoplasmic for mTHPC, endosomal for TPCS2a). These two agents demonstrated different intracellular impact.
doi:10.1371/journal.pone.0084850 pmid:24386423 pmcid:PMC3874004 fatcat:6xmpf57drvathkqczxcnrorprm

A non-invasive radar system for automated behavioural tracking: application to sheep [article]

Alexandre Dore, Cristian Pasquaretta, Dominique Henry, Edmond Ricard, Jean-Francois Bompard, Mathieu Bonneau, Alain Boissy, Dominique Hazard, Herve Aubert, Mathieu Lihoreau
2020 bioRxiv   pre-print
Genetics 525 Selection Evolution 37, 381-401. 526 Bonneau, M., Vayssade, J.A., Troupe, W., Arquet, R., 2020. Outdoor animal tracking combining 527 neural network and time-lapse cameras.  ...  The main two methods are video detection (Bonneau et al., 2020), which can 451 in 2D up to 25m but with a precision of about 2m, and GPS detection 452 (Gwyn et al., 1995), but this requires to animals.  ... 
doi:10.1101/2020.12.09.418038 fatcat:2b5ci6aok5c3nmta3vmukaehwe

Riboswitch structure: an internal residue mimicking the purine ligand

Vanessa Delfosse, Patricia Bouchard, Eric Bonneau, Pierre Dagenais, Jean-François Lemay, Daniel A. Lafontaine, Pascale Legault
2009 Nucleic Acids Research  
The adenine and guanine riboswitches regulate gene expression in response to their purine ligand. X-ray structures of the aptamer moiety of these riboswitches are characterized by a compact fold in which the ligand forms a Watson-Crick base pair with residue 65. Phylogenetic analyses revealed a strict restriction at position 39 of the aptamer that prevents the G39-C65 and A39-U65 combinations, and mutational studies indicate that aptamers with these sequence combinations are impaired for ligand
more » ... binding. In order to investigate the rationale for sequence conservation at residue 39, structural characterization of the U65C mutant from Bacillus subtilis pbuE adenine riboswitch aptamer was undertaken. NMR spectroscopy and X-ray crystallography studies demonstrate that the U65C mutant adopts a compact ligand-free structure, in which G39 occupies the ligand-binding site of purine riboswitch aptamers. These studies present a remarkable example of a mutant RNA aptamer that adopts a native-like fold by means of ligand mimicking and explain why this mutant is impaired for ligand binding. Furthermore, this work provides a specific insight into how the natural sequence has evolved through selection of nucleotide identities that contribute to formation of the ligand-bound state, but ensures that the ligand-free state remains in an active conformation.
doi:10.1093/nar/gkp1080 pmid:20022916 pmcid:PMC2847212 fatcat:m5ndxdo53rbbtgiewb3cjteq3q

Cryogenic thermo-acoustic oscillations highlight and study in the SPIRAL2 superconducting LINAC [article]

Adnan Ghribi, Muhammad Aburas, Yoann Baumont, Pierre-Emmanuel Bernaudin, Stéphane Bonneau, Jean-François Leyge, Jean-Pierre Thermeau, Yann Thivel, Laurent Valentin, Adrien Vassal
2021 arXiv   pre-print
Cryogenic thermoacoustic oscillations is an area of interest of several studies. For superconducting accelerators, it is an unwanted phenomena that we usually want to get rid off. The SPIRAL2 superconducting accelerator had distributed Taconis all over its cryostats. This paper spans the different steps from their first detection to their damping with a highlight on the methods and the instrumentation that has been used. The presented study also sets the ground for a real life experimental
more » ... tigation of thermo-ascoustics in complex geometries such as superconducting LINACs. With modern Big data analysis and simulation tools, it also sets the ground for the developments of new data linked codes that fit these complex situations.
arXiv:2101.10768v1 fatcat:4evdvrytrbattls5fp7rahkbei

Preliminary Experiments on Unsupervised Word Discovery in Mboshi

Pierre Godard, Gilles Adda, Martine Adda-Decker, Alexandre Allauzen, Laurent Besacier, Hélène Bonneau-Maynard, Guy-Noël Kouarata, Kevin Löser, Annie Rialland, François Yvon
2016 Interspeech 2016  
The necessity to document thousands of endangered languages encourages the collaboration between linguists and computer scientists in order to provide the documentary linguistics community with the support of automatic processing tools. The French-German ANR-DFG project Breaking the Unwritten Language Barrier (BULB) aims at developing such tools for three mostly unwritten African languages of the Bantu family. For one of them, Mboshi, a language originating from the "Cuvette" region of the
more » ... lic of Congo, we investigate unsupervised word discovery techniques from an unsegmented stream of phonemes. We compare different models and algorithms, both monolingual and bilingual, on a new corpus in Mboshi and French, and discuss various ways to represent the data with suitable granularity. An additional French-English corpus allows us to contrast the results obtained on Mboshi and to experiment with more data.
doi:10.21437/interspeech.2016-886 dblp:conf/interspeech/GodardAAABBKLRY16 fatcat:2ciunq76qjfe3gbcgpydza22lm

Constitutive Regulatory Activity of an Evolutionarily Excluded Riboswitch Variant

Renaud Tremblay, Jean-François Lemay, Simon Blouin, Jérôme Mulhbacher, Éric Bonneau, Pascale Legault, Paul Dupont, J. Carlos Penedo, Daniel A. Lafontaine
2011 Journal of Biological Chemistry  
The exquisite specificity of the adenine-responsive riboswitch toward its cognate metabolite has been shown to arise from the formation of a Watson-Crick interaction between the adenine ligand and residue U65. A recent crystal structure of a U65C adenine aptamer variant has provided a rationale for the phylogenetic conservation observed at position 39 for purine aptamers. The G39-C65 variant adopts a compact ligand-free structure in which G39 is accommodated by the ligand binding site and is
more » ... e-paired to the cytosine at position 65. Here, we demonstrate using a combination of biochemical and biophysical techniques that the G39-C65 base pair not only severely impairs ligand binding but also disrupts the functioning of the riboswitch in vivo by constitutively activating gene expression. Folding studies using single-molecule FRET revealed that the G39-C65 variant displays a low level of dynamic heterogeneity, a feature reminiscent of ligand-bound wild-type complexes. A restricted conformational freedom together with an ability to significantly fold in monovalent ions are exclusive to the G39-C65 variant. This work provides a mechanistic framework to rationalize the evolutionary exclusion of certain nucleotide combinations in favor of sequences that preserve ligand binding and gene regulation functionalities.
doi:10.1074/jbc.m111.229047 pmid:21676871 pmcid:PMC3149334 fatcat:urripi6zxvh7jjd5zs3rzlie2a

Cystatin C-based Equations in Renal Transplantation: Moving Toward a Better Glomerular Filtration Rate Prediction?

Nicolas Maillard, Christophe Mariat, Christine Bonneau, Manolie Mehdi, Lise Thibaudin, Silvy Laporte, Eric Alamartine, Annette Chamson, François Berthoux
2008 Transplantation  
Creatinine-based glomerular filtration rate (GFR) estimators perform poorly in renal transplant recipients. Cystatin C might be a better alternative to serum creatinine in assessing renal graft function. We compared several cystatin C-based equations with the modification diet renal disease (MDRD) equation in 120 adult renal transplant recipients for whom the GFR was measured by the gold standard inulin clearance. Mean inulin-measured GFR was 52.6 mL/min/1.73 m 2 (range, 13-119). The Hoek,
more » ... Le Bricon, and Filler cystatin C-based formulas showed significantly better performances (accuracy 30% of 82%, 81%, 78%, and 71%), than the MDRD equation (58%, Mac Nemar test, PϽ0.01). Sensitivity to detect a GFR below 60 mL/min/1.73 m 2 was significantly higher for the Hoek and the Rule equations (0.95, 95% CI 0.91-1) than for the MDRD equation (0.76, 95% CI 0.67-0.85). These data confirm that cystatin C as a GFR marker offers significant advantages over creatinine in renal transplantation.
doi:10.1097/tp.0b013e3181744225 pmid:18580481 fatcat:phiupqzndbfmjc74kgejfiozf4

Impact of a stochastic sequential initiation of fractures on the spatial correlations and connectivity of discrete fracture networks

François Bonneau, Guillaume Caumon, Philippe Renard
2016 Journal of Geophysical Research - Solid Earth  
., 2005; Bonneau et al., 2013] . Among these methods, Cladouhos and Marrett [1996] relate a simplified two-dimensional linkage model to the emergence of power law distributions.  ...  Several authors have integrated such simplified geomechanical models in stochastic DFN simulations [Cladouhos and Marrett, 1996; Srivastava et al., 2005; Bonneau et al., 2013] .  ... 
doi:10.1002/2015jb012451 fatcat:6ai6wrabnzh6tjlrkcpogahgla
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