35 results on '"Rubén Ibáñez"'
Search Results
2. No Habitat Selection during Spring Migration at a Meso-Scale Range across Mosaic Landscapes: A Case Study with the Woodcock (Scolopax rusticola).
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Ariñe Crespo, Marcos Rodrigues, Ibon Telletxea, Rubén Ibáñez, Felipe Díez, Joseba F Tobar, and Juan Arizaga
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Medicine ,Science - Abstract
Success of migration in birds in part depends on habitat selection. Overall, it is still poorly known whether there is habitat selection amongst landbird migrants moving across landscapes. Europe is chiefly covered by agro-forestry mosaic landscapes, so migratory species associated to either agricultural landscapes or woodland habitats should theoretically find suitable stopover sites along migration. During migration from wintering to breeding quarters, woodcocks (Scolopax rusticola) tagged with PTT satellite-tracking transmitters were used to test for the hypothesis that migrants associated to agro-forest habitats have no habitat selection during migration, at a meso-scale level. Using a GIS platform we extracted at a meso-scale range habitat cover at stopover localities. Results obtained from comparisons of soil covers between points randomly selected and true stopover localities sites revealed, as expected, the species may not select for particular habitats at a meso-scale range, because the habitat (or habitats) required by the species can be found virtually everywhere on their migration route. However, those birds stopping over in places richer in cropland or mosaic habitats including both cropland and forest and with proportionally less closed forest stayed for longer than in areas with lower surfaces of cropland and mosaic and more closed forest. This suggests that areas rich in cropland or mosaic habitat were optimal.
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- 2016
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3. On the Proper Generalized Decomposition applied to microwave processes involving multilayered components.
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H. Tertrais, Rubén Ibáñez, Anais Barasinski, Chady Ghnatios, and Francisco Chinesta
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- 2019
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4. Numerical experiments on unsupervised manifold learning applied to mechanical modeling of materials and structures
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Elías Cueto, Francisco Chinesta, Rubén Ibáñez, Pierre Gilormini, Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), University of Zaragoza - Universidad de Zaragoza [Zaragoza], The first, third, and fourth authors are supported by their respective ESI Group research chairs, and their support is gratefully acknowledged. The first author is supported by CREATE-ID ESI-ENSAM research chair. The third author is supported by the ESI Group Chair at the University of Zaragoza. The fourth author is supported by CREATE-ID ESI-ENSAM research chair.
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Computer Science::Machine Learning ,Work (thermodynamics) ,State variable ,Theoretical computer science ,Matériaux [Sciences de l'ingénieur] ,Computer science ,k-PCA ,Structural system ,Structural analysis ,02 engineering and technology ,[SPI.MECA.MSMECA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Materials and structures in mechanics [physics.class-ph] ,law.invention ,0203 mechanical engineering ,law ,Material constitutive equations ,General Materials Science ,Dimensionality reduction ,Nonlinear dimensionality reduction ,State variables ,020303 mechanical engineering & transports ,ComputingMethodologies_PATTERNRECOGNITION ,Mechanics of Materials ,Nonsupervised manifold learning ,Manifold (fluid mechanics) ,Curse of dimensionality - Abstract
The present work aims at analyzing issues related to the data manifold dimensionality. The interest of the study is twofold: (i) first, when too many measurable variables are considered, manifold learning is expected to extract useless variables; (ii) second, and more important, the same technique, manifold learning, could be utilized for identifying the necessity of employing latent extra variables able to recover single-valued outputs. Both aspects are discussed in the modeling of materials and structural systems by using unsupervised manifold learning strategies. The first, third, and fourth authors are supported by their respective ESI Group research chairs; their support is gratefully acknowledged. The first author is supported by CREATE-ID ESI-ENSAM research chair. The third author is supported by the ESI Group Chair at the University of Zaragoza. The fourth author is supported by CREATE-ID ESI-ENSAM research chair.
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- 2021
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5. Radars in transport applications
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Francisco Chinesta, Rubén Ibáñez Pinillo, Erik Abenius, Antonio Huerta, Emmanuelle Abisset-Chavanne, Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, Universitat Politècnica de Catalunya. LACÀN - Mètodes Numèrics en Ciències Aplicades i Enginyeria, École Centrale de Nantes (ECN), Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), ESI Group (ESI Group), and Universitat Politècnica de Catalunya [Barcelona] (UPC)
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Programming (Mathematics) ,Matemàtiques i estadística::Investigació operativa::Programació matemàtica [Àrees temàtiques de la UPC] ,business.industry ,Dimensionality reduction ,Big data ,Process (computing) ,Nonlinear dimensionality reduction ,010103 numerical & computational mathematics ,90 Operations research, mathematical programming::90C Mathematical programming [Classificació AMS] ,Data-driven ,01 natural sciences ,ADAS ,law.invention ,Domain (software engineering) ,[SPI.MAT]Engineering Sciences [physics]/Materials ,Identification (information) ,Computer engineering ,law ,Programació (Matemàtica) ,Big-data ,0101 mathematics ,Radar ,business - Abstract
International audience; In the recent years, automotive car industry is evolving towards a new generation of autonomous vehicles, where decision making is not fully perform by the driver but it partially relies on the technology of the car itself. Indeed, a CPU inside the car will process all information coming from the sensors, distinguishing different scenarios appearing in the real life and ultimately allowing decision making. Since the CPU will be confronted with plenty of information, tools like machine learning or big-data analysis will be a useful ally to separate data from information. These existing machine learning techniques, such as kernel Principal Component Analysis (k-PCA), Locally Linear Embedding (LLE) among many other techniques, are useful to unveil the latent parameters defining a given scenario. Indeed, these algorithms have been already used to perform real-time classification of signals appearing throughout the road. Selecting the modeling of the electromagnetic response of the radar plays an important role to achieve real time constraints. Even though Helmholtz equation represents accurately the physics, the computational cost of such simulation is not affordable for real-time applications due to high radar operating frequencies, resulting into a very fine finite element mesh. On the other hand, far field approaches are not so accurate when the objects are very close due to plane wave assumption. In the first part of this work, the Geometrical Optics method is investigated in this work as a possible route to fulfill both real-time and accuracy constraints. The main hypothesis under such model is that waves are treated as straight lines constrained to optical reflection laws. Therefore, there is no need to mesh the interior of the domain. However, the accuracy of such approach is compromised when the size of the objects inside the domain are comparable to the wave lengths or in the vicinity of angular points. The second part is mainly focused on of the application of manifold learning and big data analysis into a data set of precomputed scenarios. Indeed, the identification of an unknown scenario from electromagnetic signals is purchased. Nevertheless, current research lines are devoted to give an answer to questions such as how many receptors do we need to identify unequivocally the scenario, where to locate the receptors, or which parts of the scenario have a negligible impact in the electromagnetic response.
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- 2020
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6. From elastic homogenization to upscaling of non-Newtonian fluid flows in porous media
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Elena Lopez, Adrien Scheuer, Rubén Ibáñez, Roland Keunings, Francisco Chinesta, and Emmanuelle Abisset-Chavanne
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Materials science ,02 engineering and technology ,01 natural sciences ,Homogenization (chemistry) ,Non-Newtonian fluid ,Physics::Geophysics ,010101 applied mathematics ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Macroscopic scale ,Computational mechanics ,General Materials Science ,Statistical physics ,0101 mathematics ,Porous medium - Abstract
Upscaling behaviors of heterogeneous microstructures to define macroscopic effective media is of major interest in many areas of computational mechanics, in particular those related to materials and processes engineering. In this paper, we explore the possibility of defining a macroscopic behavior manifold from microscopic calculations, and then use it directly for efficiently performing manifold-based simulations at the macroscopic scale. We consider in this work upscaling of non-Newtonian flows in porous media, and more particularly the ones involving short-fibre suspensions.
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- 2017
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7. Data-driven non-linear elasticity: constitutive manifold construction and problem discretization
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Domenico Borzacchiello, Rubén Ibáñez, Jose Vicente Aguado, Francisco Chinesta, Elías Cueto, Emmanuelle Abisset-Chavanne, Pierre Ladevèze, ESI Group (ESI), ESI Group, Ingénierie des Matériaux Polymères (IMP), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon, Institut de Recherche en Génie Civil et Mécanique (GeM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Centre National de la Recherche Scientifique (CNRS), Aragón Institute of Engineering Research [Zaragoza] (I3A), University of Zaragoza - Universidad de Zaragoza [Zaragoza], Laboratoire de Mécanique et Technologie (LMT), École normale supérieure - Cachan (ENS Cachan)-Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
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Inverse problems ,Mathematical optimization ,Discretization ,Computer science ,Constitutive equation ,Computational Mechanics ,Ocean Engineering ,02 engineering and technology ,01 natural sciences ,Data-driven ,law.invention ,Data-intensive simulation ,[PHYS.MECA.STRU]Physics [physics]/Mechanics [physics]/Structural mechanics [physics.class-ph] ,0203 mechanical engineering ,law ,Computational mechanics ,Constitutive manifold ,0101 mathematics ,Axiom ,Applied Mathematics ,Mechanical Engineering ,Experimental data ,Data-driven computational mechanics ,Inverse problem ,010101 applied mathematics ,Computational Mathematics ,020303 mechanical engineering & transports ,Computational Theory and Mathematics ,Manifold (fluid mechanics) - Abstract
The use of constitutive equations calibrated from data has been implemented into standard numerical solvers for successfully addressing a variety problems encountered in simulation-based engineering sciences (SBES). However, the complexity remains constantly increasing due to the need of increasingly detailed models as well as the use of engineered materials. Data-Driven simulation constitutes a potential change of paradigm in SBES. Standard simulation in computational mechanics is based on the use of two very different types of equations. The first one, of axiomatic character, is related to balance laws (momentum, mass, energy, $$\ldots $$ ), whereas the second one consists of models that scientists have extracted from collected, either natural or synthetic, data. Data-driven (or data-intensive) simulation consists of directly linking experimental data to computers in order to perform numerical simulations. These simulations will employ laws, universally recognized as epistemic, while minimizing the need of explicit, often phenomenological, models. The main drawback of such an approach is the large amount of required data, some of them inaccessible from the nowadays testing facilities. Such difficulty can be circumvented in many cases, and in any case alleviated, by considering complex tests, collecting as many data as possible and then using a data-driven inverse approach in order to generate the whole constitutive manifold from few complex experimental tests, as discussed in the present work.
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- 2017
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8. From linear to nonlinear PGD-based parametric structural dynamics
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Jean Louis Duval, Elías Cueto, Rubén Ibáñez, Clara Argerich Martin, Francisco Chinesta, Giacomo Quaranta, ESI Group (ESI), ESI Group, Institut de Recherche en Génie Civil et Mécanique (GeM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Centre National de la Recherche Scientifique (CNRS), École Nationale Supérieure d'Arts et Métiers (ENSAM), Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), Aragón Institute of Engineering Research [Zaragoza] (I3A), University of Zaragoza - Universidad de Zaragoza [Zaragoza], Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), and Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies
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Marketing ,Computer science ,Linear and nonlinear parametric dynamics ,Strategy and Management ,Modal analysis ,Computation ,Low frequency domain ,02 engineering and technology ,[SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph] ,Sciences de l'ingénieur ,Proper Generalized Decomposition ,Domain (software engineering) ,Harmonic analysis ,Nonlinear system ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Frequency domain ,Media Technology ,Applied mathematics ,General Materials Science ,Affine transformation ,Linear and nonlinear parametric dynamics - Proper Generalized Decomposition - Harmonic analysis - Modal analysis - Low frequency domain ,Parametric statistics - Abstract
International audience; The present paper analyzes different integration schemes of solid dynamics in the frequency domain involving the so-called Proper Generalized Decomposition-PGD. The last framework assumes for the solution a parametric dependency with respect to frequency. This procedure allowed introducing other parametric dependences related to loading, geometry, and material properties. However, in these cases, affine decompositions are required for an efficient computation of separated representations. A possibility for circumventing such difficulty consists in combining modal and harmonic analysis for defining an hybrid integration scheme. Moreover, such a procedure, as proved in the present work, can be easily generalized to address nonlinear parametric dynamics, as well as to solve problems with non-symmetric stiffness matrices, always operating in the domain of low frequencies.
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- 2019
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9. Some applications of compressed sensing in computational mechanics: model order reduction, manifold learning, data-driven applications and nonlinear dimensionality reduction
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Francisco Chinesta, Rubén Ibáñez, Amine Ammar, Elías Cueto, Jean Louis Duval, Emmanuelle Abisset-Chavanne, ESI Group (ESI Group), Institut de Calcul Intensif (ICI), École Centrale de Nantes (ECN), University of Zaragoza - Universidad de Zaragoza [Zaragoza], Laboratoire Angevin de Mécanique, Procédés et InnovAtion (LAMPA), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-Institut Polytechnique de Bordeaux-Université de Bordeaux (UB), Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, and HESAM Université (HESAM)-HESAM Université (HESAM)
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Model order reduction ,Matériaux [Sciences de l'ingénieur] ,Computer science ,Applied Mathematics ,Mechanical Engineering ,Computational Mechanics ,Nonlinear dimensionality reduction ,Signal compression ,Ocean Engineering ,02 engineering and technology ,01 natural sciences ,Signal ,Field (computer science) ,[SPI.MAT]Engineering Sciences [physics]/Materials ,010101 applied mathematics ,Computational Mathematics ,020303 mechanical engineering & transports ,Compressed sensing ,0203 mechanical engineering ,Computational Theory and Mathematics ,Computational mechanics ,Nyquist–Shannon sampling theorem ,0101 mathematics ,Algorithm - Abstract
International audience; Compressed sensing is a signal compression technique with very remarkable properties. Among them, maybe the most salient one is its ability of overcoming the Shannon–Nyquist sampling theorem. In other words, it is able to reconstruct a signal at less than 2Q samplings per second, where Q stands for the highest frequency content of the signal. This property has, however, important applications in the field of computational mechanics, as we analyze in this paper. We consider a wide variety of applications, such as model order reduction, manifold learning, data-driven applications and nonlinear dimensionality reduction. Examples are provided for all of them that show the potentialities of compressed sensing in terms of CPU savings in the field of computational mechanics.
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- 2019
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10. On the Proper Generalized Decomposition applied to microwave processes involving multilayered components
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Hermine Tertrais, Chady Ghnatios, Francisco Chinesta, Anais Barasinski, Rubén Ibáñez, Institut de Recherche en Génie Civil et Mécanique (GeM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Centre National de la Recherche Scientifique (CNRS), École Centrale de Nantes (ECN), Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, and HESAM Université (HESAM)-HESAM Université (HESAM)
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General Computer Science ,Computer science ,Regularized double-curl ,Stacking ,010103 numerical & computational mathematics ,02 engineering and technology ,Sciences de l'ingénieur ,01 natural sciences ,Theoretical Computer Science ,[SPI.MAT]Engineering Sciences [physics]/Materials ,symbols.namesake ,Electric field ,0202 electrical engineering, electronic engineering, information engineering ,0101 mathematics ,Representation (mathematics) ,Separated representation ,PGD ,Numerical Analysis ,Sequence ,Thin layers ,Plane (geometry) ,Applied Mathematics ,Mathematical analysis ,Multilayered components ,Discontinuity (linguistics) ,[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism ,Maxwell's equations ,Maxwell equations ,Modeling and Simulation ,symbols ,020201 artificial intelligence & image processing - Abstract
International audience; Many electrical and structural components are constituted of a stacking of multiple thin layers with different electromagnetic, mechanical and thermal properties. When 3D descriptions become compulsory the approximation of the fields along the thickness direction could involve thousands of nodes. To circumvent the numerical difficulties that such a rich description imply, we recently propose an in-plane–out-of-plane separated representation with the aim of computing fully 3D solutions as a sequence of 2D problems defined in the plane and others (1D) in the thickness. The main contribution of the present work is the proposal of an efficient in-plane–out-of-plane separated representation of the double-curl formulation of Maxwell equations able to address thin-layer laminates while ensuring the continuity and discontinuity of the tangential and normal electric field components respectively at the plies interface
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- 2019
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11. A Manifold Learning Approach to Data-Driven Computational Elasticity and Inelasticity
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Elías Cueto, Emmanuelle Abisset-Chavanne, Francisco Chinesta, Rubén Ibáñez, David González, and Jose Vicente Aguado
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Generality ,Theoretical computer science ,Computer science ,Applied Mathematics ,Nonlinear dimensionality reduction ,02 engineering and technology ,Universal law ,01 natural sciences ,Synthetic data ,Computer Science Applications ,Data-driven ,010101 applied mathematics ,020303 mechanical engineering & transports ,0203 mechanical engineering ,0101 mathematics ,Elasticity (economics) ,Algorithm ,Relevant information ,Axiom - Abstract
Standard simulation in classical mechanics is based on the use of two very different types of equations. The first one, of axiomatic character, is related to balance laws (momentum, mass, energy, ...), whereas the second one consists of models that scientists have extracted from collected, natural or synthetic data. Even if one can be confident on the first type of equations, the second one contains modeling errors. Moreover, this second type of equations remains too particular and often fails in describing new experimental results. The vast majority of existing models lack of generality, and therefore must be constantly adapted or enriched to describe new experimental findings. In this work we propose a new method, able to directly link data to computers in order to perform numerical simulations. These simulations will employ axiomatic, universal laws while minimizing the need of explicit, often phenomenological, models. This technique is based on the use of manifold learning methodologies, that allow to extract the relevant information from large experimental datasets.
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- 2016
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12. Application of Machine Learning Tools for the Improvement of Reactive Extrusion Simulation
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Karim Delage, Fanny Casteran, Clara Argerich, Philippe Cassagnau, Francisco Chinesta, Rubén Ibáñez, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon, Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), and This research was funded by the French ANR through the DataBEST project.
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Matériaux [Sciences de l'ingénieur] ,Materials science ,Polymers and Plastics ,General Chemical Engineering ,Complex system ,02 engineering and technology ,Reactive extrusion ,010402 general chemistry ,computer.software_genre ,Machine learning ,01 natural sciences ,[SPI.MAT]Engineering Sciences [physics]/Materials ,reactive extrusion ,Matrix (mathematics) ,chemistry.chemical_compound ,Materials Chemistry ,polymer processing ,Polypropylene ,business.industry ,Organic Chemistry ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Simulation software ,artificial engineering ,machine learning ,chemistry ,experimental data ,Extrusion ,Artificial intelligence ,0210 nano-technology ,business ,computer - Abstract
The purpose of this paper is to combine a classical 1D twin-screw extrusion model with machine learning techniques to obtain accurate predictions of a complex system despite few data. Systems involving reactive polyethylene oligomer dispersed in situ in a polypropylene matrix by reactive twin-screw extrusion are studied for this purpose. The twin-screw extrusion simulation software LUDOVIC is used and machine learning techniques dealing with low data limit are used as a correction of the simulation. This research was funded by the French ANR through the DataBEST project.
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- 2020
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13. On the Data-Driven Modeling of Reactive Extrusion
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Fanny Casteran, Francisco Chinesta, Rubén Ibáñez, Nicolas Hascoet, Clara Argerich, Amine Ammar, Philippe Cassagnau, Chady Ghnatios, Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), Ingénierie des Matériaux Polymères (IMP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Notre Dame University-Louaize [Lebanon] (NDU), Laboratoire Angevin de Mécanique, Procédés et InnovAtion (LAMPA), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Arts et Métiers Sciences et Technologies, and HESAM Université (HESAM)-HESAM Université (HESAM)-Institut Polytechnique de Bordeaux-Université de Bordeaux (UB)
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Matériaux [Sciences de l'ingénieur] ,Materials science ,Thermoplastic ,Plastics extrusion ,Thermosetting polymer ,02 engineering and technology ,Reactive extrusion ,lcsh:Thermodynamics ,01 natural sciences ,[SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph] ,010305 fluids & plasmas ,reactive extrusion ,Modeling and simulation ,chemistry.chemical_compound ,[INFO.INFO-LG]Computer Science [cs]/Machine Learning [cs.LG] ,0203 mechanical engineering ,lcsh:QC310.15-319 ,digital twin ,0103 physical sciences ,Composite material ,polymer processing ,lcsh:QC120-168.85 ,Fluid Flow and Transfer Processes ,Polypropylene ,chemistry.chemical_classification ,Mechanical Engineering ,Epoxy ,Condensed Matter Physics ,[SPI.MECA.GEME]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanical engineering [physics.class-ph] ,artificial engineering ,machine learning ,020303 mechanical engineering & transports ,chemistry ,visual_art ,data-driven ,visual_art.visual_art_medium ,lcsh:Descriptive and experimental mechanics ,Extrusion - Abstract
International audience; This paper analyzes the ability of different machine learning techniques, able to operate in the low-data limit, for constructing the model linking material and process parameters with the properties and performances of parts obtained by reactive polymer extrusion. The use of data-driven approaches is justified by the absence of reliable modeling and simulation approaches able to predict induced properties in those complex processes. The experimental part of this work is based on the in situ synthesis of a thermoset (TS) phase during the mixing step with a thermoplastic polypropylene (PP) phase in a twin-screw extruder. Three reactive epoxy/amine systems have been considered and anhydride maleic grafted polypropylene (PP-g-MA) has been used as compatibilizer. The final objective is to define the appropriate processing conditions in terms of improving the mechanical properties of these new PP materials by reactive extrusion.
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- 2020
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14. La variación de la forma del ala asociada con la edad difiere entre órdenes de aves: implicaciones para la interpretación del índice apuntamiento (eje C2) en un ‘size-constrained principal component analysis' (SCCA)
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Rubén Ibáñez, José Francisco Lima-Barbero, Xabier Cabodevilla, Antón Pérez-Rodríguez, Lara Moreno-Zarate, Beatriz Arroyo, Andrea Gerboles, Javier Pérez-Tris, Diego Villanúa, Maria Cruz Camacho, and Eusko Jaurlaritza
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0106 biological sciences ,Predator escape ,Wing ,biology ,Flight speed ,Zoology ,Moult ,010603 evolutionary biology ,01 natural sciences ,Passerine ,010605 ornithology ,Variation (linguistics) ,Morfología alar ,Age related ,Feather ,visual_art ,biology.animal ,Principal component analysis ,visual_art.visual_art_medium ,Muda ,Juvenile ,Selection forces ,Animal Science and Zoology ,Manoeuvrability ,Ecology, Evolution, Behavior and Systematics - Abstract
[EN]: There is a strong relationship between bird wing morphology and flight style. Wing shapes are related to manoeuvrability, flight speed, energetic costs during flight and take-off speed. Wing shape differences among species have been frequently studied but differences can also be found within species, between sexes and age groups. Many studies have assessed differences in wing shape between juveniles and adults in different passerine species but little is known about such differences in other bird orders. Performing a Size Constrained Components Analysis (SCCA) and a graphical approximation, we analysed the wing shape of juveniles and adults of eight species, including four passerines and four non-passerines of three different orders. According to a graphical approximation, we observed that wing shape differences between age groups differ among species. In the non-passerine species considered, juveniles have more pointed and concave wings than adults. In contrast, in the four passerine species, juveniles have more rounded wings than adults. However, the results for the C2 axis of SCCA (index of pointedness) do not completely agree with the graphical approximation. Our results showed that the C2 axis does not represent the same vector of wing shape variation in all species. The contribution of changes in C2 to variation in wing pointedness seemed to depend on the position of the wing tip, which is a good index of pointedness only when the wing tip is in the two most distal primary feathers. Surprisingly, the adults of some species do not have longer wings than the corresponding juveniles, because the feathers that define the wing tip do not grow longer during the first complete moult. We discuss the role of the first complete moult in changing the shape of juvenile wings into adult wings, and the implications of our results for the analysis of bird wing shape. [ES]: Existe una fuerte relación entre la morfología alar y el estilo de vuelo de un ave. La forma del ala está relacionada con la maniobrabilidad, la velocidad de vuelo, los costes energéticos durante el vuelo o la velocidad de despegue. Las diferencias en la forma del ala entre especies han sido estudiadas con frecuencia, pero también existen diferencias dentro de una especie, entre sexos y grupos de edad. Muchos estudios han evaluado las diferencias en la forma alar entre juveniles y adultos en diferentes especies de paseriformes, pero se sabe poco acerca de las diferencias en la forma alar entre grupos de edad en otros órdenes de aves. Realizando un análisis SCCA (‘Size Constrained Components Analysis’) y una aproximación gráfica, analizamos la forma alar de juveniles y adultos de ocho especies, cuatro paseriformes y cuatro no paseriformes de tres órdenes diferentes. De acuerdo con la aproximación gráfica, observamos que las diferencias en la forma alar entre grupos de edad difieren entre especies. En las especies de no paseriformes estudiadas, los juveniles tienen alas más puntiagudas y cóncavas que los adultos. En contraste, en las cuatro especies de paseriformes, los juveniles tienen alas más redondeadas que los adultos. Sin embargo, los resultados del eje C2 del SCCA no concuerdan completamente con la aproximación gráfica. nuestros resultados mostraron que el eje C2 no representa el mismo vector de variación de la forma del ala en todas las especies. La contribución de los cambios en C2 a la variación del apuntamiento del ala parece depender de la posición de la punta del ala, siendo un buen índice de apuntamiento solo cuando la punta del ala está en las dos plumas primarias más distales. Sorprendentemente, los adultos de algunas especies no tienen alas más largas que los respectivos juveniles, debido a que la pluma que define la punta del ala no tiene un incremento de tamaño durante la primera muda completa. Describimos cómo la primera muda completa es clave en el cambio de la morfología alar entre el ala de los juveniles y el ala de los adultos, y discutimos las implicaciones de nuestros resultados en relación con el análisis de la forma de las alas de las aves. Xabier Cabodevilla was supported by a PhD Grant, financed by the Basque Country Government (Grant no. PRE_2018_2_0273).
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- 2020
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15. Data-Driven Computational Plasticity
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Rubén Ibáñez, Elías Cueto, Emmanuelle Abisset-Chavanne, Pierre Ladevèze, Jose Vicente Aguado, and Francisco Chinesta
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Work (thermodynamics) ,Mathematical optimization ,Computer science ,Constitutive equation ,02 engineering and technology ,General Medicine ,Universal law ,01 natural sciences ,Synthetic data ,Variety (cybernetics) ,Data-driven ,010101 applied mathematics ,Momentum ,020303 mechanical engineering & transports ,0203 mechanical engineering ,0101 mathematics ,Axiom - Abstract
The use of constitutive equations calibrated from data collected from adequate testing has been implemented successfully into standard solvers for successfully addressing a variety of problems encountered in SBES (simulation based engineering sciences). However, the complexity remains constantly increasing due to the more and more fine models being considered as well as the use of engineered materials. Data-Driven simulation constitutes a potential change of paradigm in SBES. Standard simulation in classical mechanics is based on the use of two very different types of equations. The first one, of axiomatic character, is related to balance laws (momentum, mass, energy...), whereas the second one consists of models that scientists have extracted from collected, natural or synthetic data. Data-driven simulation consists of directly linking data to computers in order to perform numerical simulations. These simulations will use universal laws while minimizing the need of explicit, often phenomenological, models. This work revisits our former work on data-driven computational linear and nonlinear elasticity and the rationale is extended for addressing computational inelasticity (viscoelastoplasticity).
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- 2018
16. A new hybrid explicit/implicit in-plane-out-of-plane separated representation for the solution of dynamic problems defined in plate-like domains
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Eberhard Haug, Francisco Chinesta, Giacomo Quaranta, Alain Trameçon, Brice Bognet, Rubén Ibáñez, École Centrale de Nantes (ECN), Institut de Recherche en Génie Civil et Mécanique (GeM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Centre National de la Recherche Scientifique (CNRS), Institut de Calcul Intensif (ICI), ESI Group (ESI), ESI Group, Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, and HESAM Université (HESAM)-HESAM Université (HESAM)
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Discretization ,Computer science ,Constraint (computer-aided design) ,Dimension (graph theory) ,Stability (learning theory) ,02 engineering and technology ,Topology ,Sciences de l'ingénieur ,01 natural sciences ,Domain (mathematical analysis) ,Out of plane ,[SPI]Engineering Sciences [physics] ,Explicit ,Laminates ,0203 mechanical engineering ,Dynamic problem ,General Materials Science ,0101 mathematics ,Representation (mathematics) ,Civil and Structural Engineering ,PGD ,Separated representation ,Mechanical Engineering ,Hybrid time discretization ,Dynamics ,Computer Science Applications ,010101 applied mathematics ,020303 mechanical engineering & transports ,Modeling and Simulation ,Dynamics / Implicit / Explicit / Hybrid time discretization / Plates / Laminates / PGD / Separated representation ,Plates ,Implicit - Abstract
International audience; The present paper extends in-plane-out-of-plane separated representations successfully used for addressing fully 3D model solutions defined in plate-like domain, to dynamics. Common time integration are performed using explicit or implicit strategies. Even if the implementation of implicit integration schemes into a 3D in-plane-out-of-plane separated representation does not imply major difficulties, the use of explicit integration preferable in many applications becomes a tricky issue. In fact the mesh employed for discretizing the out-of-plane dimension (thickness) determines the maximum time-step ensuring stability. In this paper we introduce a new efficient hybrid explicit/implicit in-plane-out-of-plane separated representation for dynamic problems defined in plate-like domains that allows computing 3D solutions with the stability constraint exclusively determined by the coarser in-plane discretization.
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- 2018
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17. A Multidimensional Data-Driven Sparse Identification Technique: The Sparse Proper Generalized Decomposition
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David González, Emmanuelle Abisset-Chavanne, Elías Cueto, Antonio Huerta, Amine Ammar, Rubén Ibáñez, Jean Louis Duval, Francisco Chinesta, École Nationale Supérieure des Arts et Métiers (ENSAM), Laboratoire Angevin de Mécanique, Procédés et InnovAtion (LAMPA), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-Institut Polytechnique de Bordeaux-Université de Bordeaux (UB), Aragón Institute of Engineering Research [Zaragoza] (I3A), University of Zaragoza - Universidad de Zaragoza [Zaragoza], Laboratori de Càlcul Numèric (LACAN) (LaCàN), Universitat Politècnica de Catalunya [Barcelona] (UPC), ESI Group (ESI Group), Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, and Universitat Politècnica de Catalunya. LACÀN - Mètodes Numèrics en Ciències Aplicades i Enginyeria
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Engineering, Civil ,Matériaux [Sciences de l'ingénieur] ,General Computer Science ,Article Subject ,Computer science ,Engineering, Multidisciplinary ,Matemàtiques i estadística::Matemàtica aplicada a les ciències [Àrees temàtiques de la UPC] ,02 engineering and technology ,Space (mathematics) ,01 natural sciences ,lcsh:QA75.5-76.95 ,[SPI.MAT]Engineering Sciences [physics]/Materials ,0203 mechanical engineering ,70 Mechanics of particles and systems::70Q05 Control of mechanical systems [Classificació AMS] ,Sparse model ,Limit (mathematics) ,Engineering, Ocean ,0101 mathematics ,Engineering, Aerospace ,Engineering, Biomedical ,Automatic control ,Anàlisi numèrica ,Multidisciplinary ,Matemàtiques i estadística::Anàlisi numèrica::Mètodes numèrics [Àrees temàtiques de la UPC] ,Multidimensional data ,Computer Science, Software Engineering ,Engineering, Marine ,Control automàtic ,010101 applied mathematics ,Engineering, Manufacturing ,Engineering, Mechanical ,Identification (information) ,020303 mechanical engineering & transports ,Engineering, Industrial ,lcsh:Electronic computers. Computer science ,74 Mechanics of deformable solids::74S Numerical methods [Classificació AMS] ,Algorithm ,Curse of dimensionality ,Proper generalized decomposition ,Numerical analysis - Abstract
International audience; Sparse model identification by means of data is especially cumbersome if the sought dynamics live in a high dimensional space. This usually involves the need for large amount of data, unfeasible in such a high dimensional settings. This well-known phenomenon, coined as the curse of dimensionality, is here overcome by means of the use of separate representations. We present a technique based on the same principles of the Proper Generalized Decomposition that enables the identification of complex laws in the low-data limit. We provide examples on the performance of the technique in up to ten dimensions.
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- 2018
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18. A simple microstructural viscoelastic model for flowing foams
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Rubén Ibáñez, Francisco Chinesta, Antonio Huerta, Roland Keunings, Emmanuelle Abisset-Chavanne, Adrien Scheuer, École Centrale de Nantes (ECN), Institut de Calcul Intensif (ICI), Université Catholique de Louvain = Catholic University of Louvain (UCL), Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), Laboratori de Càlcul Numèric (LACAN) (LaCàN), Universitat Politècnica de Catalunya [Barcelona] (UPC), Institute of Information and Communication Technologies, Electronics and Applied Mathematics (ICTEAM), Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, Universitat Politècnica de Catalunya. LACÀN - Mètodes Numèrics en Ciències Aplicades i Enginyeria, UCL - SST/ICTM/INMA - Pôle en ingénierie mathématique, ESI Group (ESI), ESI Group, Institut de Recherche en Génie Civil et Mécanique (GeM), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Centre National de la Recherche Scientifique (CNRS)
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0209 industrial biotechnology ,Engineering, Civil ,Materials science ,74 Mechanics of deformable solids::74B Elastic materials [Classificació AMS] ,Engineering, Multidisciplinary ,02 engineering and technology ,Kinematics ,Sciences de l'ingénieur ,Viscoelasticity ,[SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph] ,Matemàtiques i estadística::Anàlisi numèrica [Àrees temàtiques de la UPC] ,[SPI]Engineering Sciences [physics] ,020901 industrial engineering & automation ,0203 mechanical engineering ,Distortion ,Point (geometry) ,General Materials Science ,Engineering, Ocean ,Strength of materials ,Flowing foams ,Conformation ,Engineering, Aerospace ,Engineering, Biomedical ,Resistència de materials ,Microstructural description ,Orientation (computer vision) ,Elasticitat ,Forming processes ,Mechanics ,Microstructure ,Computer Science, Software Engineering ,Engineering, Marine ,Elasticity ,Engineering, Manufacturing ,Engineering, Mechanical ,020303 mechanical engineering & transports ,Flow (mathematics) ,Engineering, Industrial ,Flowing foams·Viscoelasticity·Conformation·Microstructural description ,74 Mechanics of deformable solids::74S Numerical methods [Classificació AMS] - Abstract
This is a post-peer-review, pre-copyedit version of an article published in International journal of material forming. The final authenticated version is available online at: http://dx.doi.org/10.1007/s12289-018-1417-4 The numerical modelling of forming processes involving the flow of foams requires taking into account the different problem scales. Thus, in industrial applications a macroscopic approach is suitable, whereas the macroscopic flow parameters depend on the cellular structure: cell size, shape, orientation, etc. Moreover, the shape and orientation of the cells are induced by the flow. A fully microscopic description remains useful to understand the foam behaviour and the topological changes induced by the cell elongation or distortion, however, from an industrial point of view, microscopic simulations remain challenging to address practical applications involving flows in complex 3D geometries. In this paper, we propose a viscoelastic flow model where the foam microstructure is represented from suitable microstructure descriptors whose evolution is governed by the macroscopic flow kinematics.
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- 2018
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19. Hybrid constitutive modeling: data-driven learning of corrections to plasticity models
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David González, Elías Cueto, Francisco Chinesta, Emmanuelle Abisset-Chavanne, Jean Louis Duval, Rubén Ibáñez, École Nationale Supérieure des Arts et Métiers (ENSAM), ESI Group (ESI Group), University of Zaragoza - Universidad de Zaragoza [Zaragoza], Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, and HESAM Université (HESAM)-HESAM Université (HESAM)
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0209 industrial biotechnology ,Machine learning·Data-driven computational mechanics·Plasticity·Model learning ,business.industry ,Computer science ,Computational intelligence ,02 engineering and technology ,Plasticity ,16. Peace & justice ,Sciences de l'ingénieur ,Characterization (materials science) ,Data modeling ,[SPI]Engineering Sciences [physics] ,020303 mechanical engineering & transports ,020901 industrial engineering & automation ,0203 mechanical engineering ,General Materials Science ,Artificial intelligence ,business - Abstract
International audience; In recent times a growing interest has arose on the development of data-driven techniques to avoid the employ of phenomenological constitutive models. While it is true that, in general, data do not fit perfectly to existing models, and present deviations from the most popular ones, we believe that this does not justify (or, at least, not always) to abandon completely all the acquired knowledge on the constitutive characterization of materials. Instead, what we propose here is, by means of machine learning techniques, to develop correction to those popular models so as to minimize the errors in constitutive modeling.
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- 2018
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20. Simulating squeeze flows in multiaxial laminates using an improved TIF model
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Francisco Chinesta, Rubén Ibáñez, and Emmanuelle Abisset-Chavanne
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Engineering ,business.industry ,Fiber (mathematics) ,Isotropy ,Constitutive equation ,Structural engineering ,Mechanics ,Kinematics ,symbols.namesake ,Stability conditions ,Flow (mathematics) ,Lagrange multiplier ,symbols ,business ,Representation (mathematics) - Abstract
Thermoplastic composites are widely considered in structural parts. In this paper attention is paid to squeeze flow of continuous fiber laminates. In the case of unidirectional prepregs, the ply constitutive equation is modeled as a transversally isotropic fluid, that must satisfy both the fiber inextensibility as well as the fluid incompressibility. When laminate is squeezed the flow kinematics exhibits a complex dependency along the laminate thickness requiring a detailed velocity description through the thickness. In a former work the solution making use of an in-plane-out-of-plane separated representation within the PGD – Poper Generalized Decomposition – framework was successfully accomplished when both kinematic constraints (inextensibility and in-compressibility) were introduced using a penalty formulation for circumventing the LBB constraints. However, such a formulation makes difficult the calculation on fiber tractions and compression forces, the last required in rheological characterizations. In this paper the former penalty formulation is substituted by a mixed formulation that makes use of two Lagrange multipliers, while addressing the LBB stability conditions within the separated representation framework, questions never until now addressed.
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- 2017
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21. Simulation of microwave heating of a composite part in an oven cavity
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Anais Barasinski, Rubén Ibáñez, Francisco Chinesta, Chady Ghnatios, and Hermine Tertrais
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Materials science ,Discretization ,business.industry ,Microwave heating ,Composite number ,Decomposition (computer science) ,Process (computing) ,Mechanical engineering ,business ,Microwave ,Thermal energy ,Proper generalized decomposition - Abstract
Microwave (MW) technology relies on volumetric heating. Thermal energy is transferred to the material that can absorb it at specific frequencies. In this paper, a coupled thermic and electromagnetic model is proposed in order to simulate the emerging process of microwave heating for composite materials. Solving the problem in a laminated composite material requires a high degree of discretization in the thickness direction which is made possible by introducing the in-plane-out-of-plane decomposition approach using the Proper Generalized Decomposition (PGD).
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- 2017
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22. A manifold learning approach to data-driven computational materials and processes
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David González, Jean Louis Duval, Francisco Chinesta, Jose Vicente Aguado, Rubén Ibáñez, Emmanuelle Abisset-Chavanne, and Elías Cueto
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Momentum ,Theoretical computer science ,Character (mathematics) ,Computational learning theory ,Computer science ,Nonlinear dimensionality reduction ,Universal law ,Axiom ,Synthetic data ,Data-driven - Abstract
Standard simulation in classical mechanics is based on the use of two very different types of equations. The first one, of axiomatic character, is related to balance laws (momentum, mass, energy, ...), whereas the second one consists of models that scientists have extracted from collected, natural or synthetic data. In this work we propose a new method, able to directly link data to computers in order to perform numerical simulations. These simulations will employ universal laws while minimizing the need of explicit, often phenomenological, models. They are based on manifold learning methodologies.
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- 2017
23. Modeling the kinematics of multi-axial composite laminates as a stacking of 2D TIF plies
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Francisco Chinesta, Rubén Ibáñez, Antonio Huerta, Emmanuelle Abisset-Chavanne, Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, and Universitat Politècnica de Catalunya. LACÀN - Mètodes Numèrics en Ciències Aplicades i Enginyeria
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Materials science ,Kinematics ,Deformation (mechanics) ,business.industry ,Constitutive equation ,Isotropy ,Matemàtiques i estadística::Matemàtica aplicada a les ciències [Àrees temàtiques de la UPC] ,Structural engineering ,Composite laminates ,Cinemàtica ,Compression (physics) ,symbols.namesake ,Lagrange multiplier ,symbols ,70 Mechanics of particles and systems::70B Kinematics [Classificació AMS] ,Composite material ,business ,Plane stress - Abstract
Thermoplastic composites are widely considered in structural parts. In this paper attention is paid to sheet forming of continuous fiber laminates. In the case of unidirectional prepregs, the ply constitutive equation is modeled as a transversally isotropic fluid, that must satisfy both the fiber inextensibility as well as the fluid incompressibility. When the stacking sequence involves plies with different orientations the kinematics of each ply during the laminate deformation varies significantly through the composite thickness. In our former works we considered two different approaches when simulating the squeeze flow induced by the laminate compression, the first based on a penalty formulation and the second one based on the use of Lagrange multipliers. In the present work we propose an alternative approach that consists in modeling each ply involved in the laminate as a transversally isotropic fluid – TIF - that becomes 2D as soon as incompressibility constraint and plane stress assumption are taken into account. Thus, composites laminates can be analyzed as a stacking of 2D TIF models that could eventually interact by using adequate friction laws at the inter-ply interfaces.
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- 2016
24. Dynamics of the ceramic ultrafiltration of model proteins with different isoelectric point: Comparison of β-lactoglobulin and lysozyme
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Antonio Guadix, Rubén Ibáñez, M. Carmen Almécija, and Emilia M. Guadix
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Chromatography ,Chemistry ,Ultrafiltration ,Filtration and Separation ,Fractionation ,Analytical Chemistry ,Membrane technology ,chemistry.chemical_compound ,Ceramic membrane ,Isoelectric point ,Ionic strength ,visual_art ,visual_art.visual_art_medium ,Ceramic ,Lysozyme - Abstract
The study of the electrostatic interactions in the ultrafiltration of single model proteins is an important topic for the biotechnology industry interested in the fractionation of protein mixtures. In this paper, the dynamics of the ultrafiltration of β-lactoglobulin and lysozyme through a 300 kDa tubular ceramic membrane was investigated. The time evolution of permeate flux and protein transmission were determined at a temperature of 30 °C, a cross-flow velocity of 3.5 m/s and a transmembrane pressure of 100 kPa. The influence of pH was monitored in the 3–9 interval for β-lactoglobulin and in the 5–12 interval for lysozyme. The effect of ionic strength was studied by increasing the addition of NaCl up to 15 mM. The curves of permeate flux were discussed according to the resistances in series model. Since β-lactoglobulin and lysozyme have acid and alkaline isoelectric points, respectively, the results showed different responses with respect to the electrostatic environment.
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- 2007
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25. Immunogenicity and Safety of a Pediatric Dose of a Virosome-Adjuvanted Hepatitis A Vaccine
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Marjory Hunt, André Vertruyen, Christian Herzog, Rubén Ibáñez, Marie Van der Wielen, Pierre Van Damme, and G Froesner
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Male ,Microbiology (medical) ,Pediatrics ,medicine.medical_specialty ,Adolescent ,viruses ,Hepatitis A vaccine ,Immunization, Secondary ,Pain ,Antibodies, Viral ,Injections, Intramuscular ,Virus ,law.invention ,Randomized controlled trial ,law ,medicine ,Humans ,Child ,Hepatitis A Vaccines ,business.industry ,Immunogenicity ,fungi ,Infant ,virus diseases ,Hepatitis A ,biochemical phenomena, metabolism, and nutrition ,medicine.disease ,digestive system diseases ,Virosome ,Vaccines, Virosome ,Vaccination ,Treatment Outcome ,Infectious Diseases ,Erythema ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,Immunology ,Female ,Viral disease ,business - Abstract
The availability of pediatric formulations of hepatitis A virus (HAV) vaccines would facilitate the introduction of universal mass vaccination against HAV. The objective of this study was to compare a pediatric dose (0.25 mL) of Epaxal, a virosomal, aluminum-free HAV vaccine, to 0.5 mL standard dose, and to alum-adsorbed HAV vaccine.Subjects aged 1-16 years, stratified for age, were randomized (2:2:1) into group A (0.25 mL Epaxal), group B (0.5 mL Epaxal), or group C (Havrix Junior). Vaccines were administered at months 0, 6. Seroprotection rates (or=10 mIU/mL anti-HAV antibodies) were assessed for noninferiority, defined as lower limit of 1-sided 97.5% CI-10%. Incidence of local solicited adverse events and unsolicited adverse events were recorded.Mean age of 308 enrolled subjects was 8.9 years (range, 1.0-17.0 years). All 3 vaccines were highly immunogenic. Noninferiority of group A versus group B and group C with regard to seroprotection was demonstrated after both vaccine doses for the entire study group and for all age subgroups (11-23 months, 2-4, 5-7, 8-10, 11-13, 14-16 years). One month after first vaccination, geometric mean antibody concentrations were 69.0, 83.5, and 50.5 mIU/mL for the 3 groups, respectively (A versus B, P = 0.0208; A versus C, P = 0.0015). Local injection site pain occurred more frequently in group C than in groups A and B. No subjects withdrew from study or reported any vaccine-related serious adverse event.In children aged 1-16 years, 0.25 mL dose of Epaxal is as immunogenic as standard 0.5 mL dose and Havrix Junior. The aluminum-free vaccine compares favorably to comparator vaccine regarding local reactogenicity.
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- 2007
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26. Influence of pH and salt concentration on the cross-flow microfiltration of BSA through a ceramic membrane
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Emilio J. de la Casa, Emilia M. Guadix, Rubén Ibáñez, and Antonio Guadix
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Environmental Engineering ,Chemistry ,Microfiltration ,Flow (psychology) ,Biomedical Engineering ,Analytical chemistry ,Bioengineering ,Permeation ,Isoelectric point ,Membrane ,Ceramic membrane ,Adsorption ,Point of zero charge ,Biotechnology - Abstract
In this paper, the influence of pH in the 4–8 interval and NaCl concentration up to 25 mM on the cross-flow microfiltration of BSA was investigated. A tubular ceramic membrane with a pore size of 0.14 μm was employed and its point of zero charge was calculated. The evolution of permeate flow and BSA transmission with time was determined at 45 °C, a cross-flow velocity of 3.5 m/s and a transmembrane pressure of 100 kPa. The curves of permeate flow were explained according to the resistances in series model. Maximum protein transmission was obtained at the isoelectric point of BSA (4.9), with significant transmission also at the point of zero charge of the membrane and null transmission at pH 4 and 8. The highest permeate flow was observed at pH 7 and the lowest at 4.9. Finally, the addition of salt resulted to some extent in an improvement of both protein transmission and permeate flow.
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- 2007
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27. Rate, intensity, and duration of local reactions to a virosome-adjuvanted vs. an aluminium-adsorbed hepatitis A vaccine in UK travellers
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Christian Herzog, Rubén Ibáñez, Paul D. Clarke, and Phillip Adams
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Hepatitis A vaccine ,Injections, Intramuscular ,Internal medicine ,medicine ,Humans ,Child ,Local Reaction ,Aged ,Pain Measurement ,Hepatitis A Vaccines ,Travel ,Reactogenicity ,business.industry ,Public Health, Environmental and Occupational Health ,Hepatitis A ,Diary card ,Middle Aged ,medicine.disease ,United Kingdom ,Hepatitis a virus ,Virosome ,Vaccines, Virosome ,Infectious Diseases ,Vaccines, Inactivated ,Tolerability ,Immunology ,Female ,business - Abstract
Travellers increasingly require hepatitis A virus (HAV) vaccine for overseas travel to highly endemic areas. While the inactivated HAV vaccines currently in use are all highly immunogenic, studies have shown the aluminium-free, virosome-adjuvanted vaccine Epaxal to possess a superior local tolerability profile. The objective of this study was to analyse the pattern of local reactions caused by the aluminium-free Epaxal compared with an aluminium-adjuvanted HAV vaccine.Subjects recruited from travel health centres were randomised in a 4:1 ratio to receive a single dose of either Epaxal or Havrix vaccine. Vaccinees noted adverse reactions on a 7-day diary card that was returned by mail to the centre.529 adults (or =16 years) were vaccinated, and 413 (78.1%) subjects returned diary cards, 338 (76.5%) in the Epaxal group and 75 (86.2%) in the Havrix group. Subjects reported fewer local adverse reactions for Epaxal (23.4% vs. 57.3%; p0.0001). Injection site pain categorised as Grade 2 (painful on movement) or Grade 3 (spontaneously painful) (4.7% vs. 22.7%, p=0.0001) was less frequent in the Epaxal group and resolved more quickly (or =3 days of pain, 8.6% vs. 22.7%, p=0.0001).The lower reactogenicity of the virosome-adjuvanted vaccine is an important feature for travellers.
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- 2006
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28. scorus_paper06-Data.doc
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Ariñe Crespo, Marcos Rodrigues, Ibon Telletxea, Rubén Ibáñez, Felipe Díez, Joseba F. Tobar, Juan Arizaga, Ariñe Crespo, Marcos Rodrigues, Ibon Telletxea, Rubén Ibáñez, Felipe Díez, Joseba F. Tobar, and Juan Arizaga
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- 2016
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29. Use of essential oils for the control of Varroa jacobsoni Oud. in honey bee colonies
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Rubén Ibáñez Ochoa, Nicholas W. Calderone, Stefan Bogdanov, Anton Imdorf, and Revues Inra, Import
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[SDV.EE]Life Sciences [q-bio]/Ecology, environment ,2. Zero hunger ,0106 biological sciences ,biology ,[SDV.BID]Life Sciences [q-bio]/Biodiversity ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,[SDV.BA.ZI]Life Sciences [q-bio]/Animal biology/Invertebrate Zoology ,[SDV.EE] Life Sciences [q-bio]/Ecology, environment ,010602 entomology ,[SDV.SA.SPA]Life Sciences [q-bio]/Agricultural sciences/Animal production studies ,Insect Science ,[SDV.BA.ZI] Life Sciences [q-bio]/Animal biology/Invertebrate Zoology ,[SDV.SA.SPA] Life Sciences [q-bio]/Agricultural sciences/Animal production studies ,Humanities ,ComputingMilieux_MISCELLANEOUS ,[SDV.BID] Life Sciences [q-bio]/Biodiversity ,Varroa jacobsoni - Abstract
soni, parasite des colonies d'abeilles. Le developpement de la resistance des populations de Varroa jacobsoni et le spectre de la contamination des produits du rucher ont fortement stimule la mise au point de nouvelles strategies de traitement qui diminuent la possibilite d'un developpement rapide de la resistance et l'accumulation de residus. Cet article passe en revue l'utilisation des huiles essentielles (h.e.) et de leurs composants dans la lutte contre V. jacobsoni. « Huiles essentielles » est un terme generique qui designe les composants liquides et hautement volatiles des plantes, marques par une odeur forte et caracteristique. Les terpenes (principalement les monoterpenes) representent la majeure partie (environ 90 %) de ces composants. L'eucalyptol, le camphre, le-menthol et le thymol sont des monoterpenes typiques. Chaque espece de plante tend a avoir une composition en h.e. unique. Pourtant, certaines especes ont des varietes denommees chemotypes, dont la composition en h.e. varie. On a utilise les methodes de criblage au laboratoire pour tester sur V. jacobsoni et sur les abeilles la toxicite, la repulsivite, l'attractivite, ainsi que les effets sur la reproduction, des h.e. et de leurs composants. Au total, c'est plus de 150 h.e. et composants d'h.e. qui ont ete testes (tableaux I-III), mais peu d'entre eux se sont montres efficaces lors de leur utilisation sur ruches en conditions de terrain. Une variation enorme des conditions du milieu local et des colonies, ainsi que la difficulte d'obtenir des h.e. standardisees, rendent difficile la prevision du resultat des nombreux traitements. Les residus dans le miel peuvent conduire a des effets negatifs sur le gout. L'analyse quantitative des residus est exigee pour l'enregistrement du produit. La nature complexe de beaucoup d'h.e. et le fait que de nombreux composants des h.e. sont presents a l'etat naturel dans le miel font que l'analyse des residus est difficile. Neanmoins ces difficultes disparaissent lorsqu'on utilise individuellement les composants des h.e. La plupart sont volatils et disponibles sur le marche a prix raisonnables. Parmi tous les composants testes des h.e., c'est le thymol qui a eu le meilleur resultat en apiculture pratique, Dans les essais en champ le thymol pur (tableau IV) et les melanges a base de thymol (tableau V) ont montre une activite varroacide elevee. Le thymol est bien tolere par les abeilles. Si les traitements sont effectues en dehors de la periode de miellee, les residus de thymol dans le miel n'augmentent pas lorsqu'on multiplie les traitements et restent sous le seuil de detection gustative, qui se situe entre 1,1 et 1,6 mg.kg -1 . Selon les etudes on a trouve iles residus compris entre 0,02 et 0,48 mg.kg -1 . Mais les traitements au thymol pendant la miellee peuvent conduire a des residus plus eleves qui modifient le gout du miel. Le thymol, de meme que d'autres monoterpenes tels que le menthol et le camphre, ont le statut GRAS (generally recognized as safe, generalement reconnu comme sans danger), de la FAO aux concentrations allant jusqu'a 50 mg.kg -1 . Les residus de ces substances dans le miel ne posent donc pas de probleme toxicologique. Apres un traitement au thymol les residus dans la cire sont 1 000 fois plus eleves que dans le miel, mais ils diminuent rapidement par evaporation des que le traitement est arrete.
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- 1999
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30. Influence of pH in the recovery of lactoferrin from whey with ceramic membranes
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M. Carmen Almécija, Emilia M. Guadix, Antonio Guadix, and Rubén Ibáñez
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Chromatography ,biology ,Chemistry ,Lactoferrin ,Mechanical Engineering ,General Chemical Engineering ,Ultrafiltration ,food and beverages ,Biological activity ,General Chemistry ,law.invention ,Membrane technology ,fluids and secretions ,Membrane ,Ceramic membrane ,Infant formula ,law ,biology.protein ,General Materials Science ,Filtration ,Water Science and Technology - Abstract
A wide collection of proteins in relatively low concentrations but with an important biological activity is present in bovine whey. Among them, lactoferrin shows strong bacterial and antiviral properties, preventing the growth of pathogenic organisms in the gut, stimulating the immune system and enhancing iron absorption [1]. Lactoferrin recovery from whey is therefore of great interest since it can be used in the development of improved infant formula, functional foods and nutraceuticals. To this end, methods have been devised employing, for instance, surfactant-stabilized microbubbles [2] or ion exchage chromatography [3]. In the field of membrane technology, high performance tangential flow [4] filtration has been suggested as a feasible technique to allow the separation of lactoferrin at industrial scale [5]. In this work, the effect of pH in the selectivity of lactoferrin ultrafiltration through a ceramic membrane with respect to the major whey proteins has been studied. The results obtained are useful to design an optimal strategy to exploit the electrostatic protein–membrane interactions that takes place in this process. 2. Experimental
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- 2006
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31. Use of essential oils for the control of Varroa jacobsoni Oud. in honey bee colonies
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Imdorf, Anton, primary, Bogdanov, Stefan, additional, Ochoa, Rubén Ibáñez, additional, and Calderone, Nicholas W., additional
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- 1999
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32. Tape surface characterization and classification in automated tape placement processability: Modeling and numerical analysis
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Clara Argerich, Ruben Ibáñez, Angel León, Anaïs Barasinski, Emmanuelle Abisset-Chavanne, and Francisco Chinesta
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surface characterization ,curvature ,machine learning ,ATP composites manufacturing ,consolidation ,Sparse Proper Generalized Decomposition ,nonlinear regression ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Many composite forming processes are based on the consolidation of preimpregnated preforms of different types, e.g., sheets, tapes, .... Composite plies are put in contact using different technologies and consolidation is performed by supplying heat and pressure, the first to promote molecular diffusion at the plies interface and both (heat and pressure) to facilitate the intimate contact by squeezing surface asperities. Optimal processing requires an intimate contact as large as possible between the surfaces put in contact, for different reasons: (i) first, a perfect contact becomes compulsory to make possible molecular diffusion at the interface level in order to ensure bulk properties at interfaces; (ii) second, imperfect contact conditions result in micro and meso pores located at the interface, weakening it from the mechanical point of view, where macro defects (cracks, plies delamination, etc.) are susceptible of appearing. As just indicated, the main process parameters are the applied heat and pressure, as well as the process time (associated with the laying head velocity). These parameters should be adjusted to ensure optimal consolidation, avoiding imperfect bonding or thermal degradation. However, experiments evidence that the consolidation degree is strongly dependent on the surface characteristics (roughness). The same process parameters applied to different surfaces produce very different degrees of intimate contact. The present study aims at identifying the main surface descriptors able to describe the evolution of the degree of intimate contact during processing. That knowledge is crucial for online process control in order to maximize both productivity and part quality.
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- 2018
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33. On the Data-Driven Modeling of Reactive Extrusion
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Ruben Ibañez, Fanny Casteran, Clara Argerich, Chady Ghnatios, Nicolas Hascoet, Amine Ammar, Philippe Cassagnau, and Francisco Chinesta
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reactive extrusion ,data-driven ,machine learning ,artificial engineering ,polymer processing ,digital twin ,Thermodynamics ,QC310.15-319 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
This paper analyzes the ability of different machine learning techniques, able to operate in the low-data limit, for constructing the model linking material and process parameters with the properties and performances of parts obtained by reactive polymer extrusion. The use of data-driven approaches is justified by the absence of reliable modeling and simulation approaches able to predict induced properties in those complex processes. The experimental part of this work is based on the in situ synthesis of a thermoset (TS) phase during the mixing step with a thermoplastic polypropylene (PP) phase in a twin-screw extruder. Three reactive epoxy/amine systems have been considered and anhydride maleic grafted polypropylene (PP-g-MA) has been used as compatibilizer. The final objective is to define the appropriate processing conditions in terms of improving the mechanical properties of these new PP materials by reactive extrusion.
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- 2020
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34. Simulating squeeze flows in multiaxial laminates: towards fully 3D mixed formulations
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Francisco Chinesta, Emmanuelle Abisset-Chavanne, Rubén Ibáñez, Antonio Huerta, Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, and Universitat Politècnica de Catalunya. LACÀN - Mètodes Numèrics en Ciències Aplicades i Enginyeria
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74 Mechanics of deformable solids::74P Optimization [Classificació AMS] ,Engineering, Civil ,Materials science ,Proper generalized decomposition ,Constitutive equation ,Engineering, Multidisciplinary ,Matemàtiques i estadística::Matemàtica aplicada a les ciències [Àrees temàtiques de la UPC] ,Física::Física de l'estat sòlid [Àrees temàtiques de la UPC] ,74 Mechanics of deformable solids::74C Plastic materials, materials of stress-rate and internal-variable type [Classificació AMS] ,02 engineering and technology ,Kinematics ,01 natural sciences ,symbols.namesake ,0203 mechanical engineering ,General Materials Science ,Engineering, Ocean ,0101 mathematics ,Strength of materials ,Composite laminates ,Squeeze flow ,Engineering, Aerospace ,Engineering, Biomedical ,Resistència de materials ,LBB condition ,business.industry ,Fiber (mathematics) ,Isotropy ,Structural engineering ,Mechanics ,Computer Science, Software Engineering ,Engineering, Marine ,010101 applied mathematics ,Engineering, Manufacturing ,Engineering, Mechanical ,Stability conditions ,020303 mechanical engineering & transports ,Flow (mathematics) ,Sheet forming ,Ericksen fluid ,Lagrange multiplier ,Engineering, Industrial ,symbols ,Mixed formulation ,business ,Plastics - Abstract
The final publication is available at Springer via http://dx.doi.org/10.1007/s12289-016-1309-4 Thermoplastic composites are widely considered in structural parts. In this paper attention is paid to squeeze flow of continuous fiber laminates. In the case of unidirectional prepregs, the ply constitutive equation is modeled as a transversally isotropic fluid, that must satisfy both the fiber inextensibility as well as the fluid incompressibility. When laminate is squeezed the flow kinematics exhibits a complex dependency along the laminate thickness requiring a detailed velocity description through the thickness. In a former work the solution making use of an in-plane-out-of-plane separated representation within the PGD – Poper Generalized Decomposition – framework was successfully accomplished when both kinematic constraints (inextensibility and incompressibility) were introduced using a penalty formulation for circumventing the LBB constraints. However, such a formulation makes difficult the calculation on fiber tractions and compression forces, the last required in rheological characterizations. In this paper the former penalty formulation is substituted by a mixed formulation that makes use of two Lagrange multipliers, while addressing the LBB stability conditions within the separated representation framework, questions never until now addressed.
35. Multiscale proper generalized decomposition based on the partition of unity
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Antonio Huerta, Amine Ammar, Elías Cueto, Rubén Ibáñez, Jean Louis Duval, Francisco Chinesta, Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, Universitat Politècnica de Catalunya. LACÀN - Mètodes Numèrics en Ciències Aplicades i Enginyeria, Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), Laboratoire Angevin de Mécanique, Procédés et InnovAtion (LAMPA), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM)-Institut Polytechnique de Bordeaux-Université de Bordeaux (UB), University of Zaragoza - Universidad de Zaragoza [Zaragoza], Universitat Politècnica de Catalunya [Barcelona] (UPC), ESI Group (ESI Group), and The Spanish Ministry of Economy and Competitiveness through grant DPI2015-72365-EXP, and by the Regional Government of Aragon and the European Social Fund (research group T24 17R).
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Matériaux [Sciences de l'ingénieur] ,Discretization ,Computer science ,partition of unity ,02 engineering and technology ,Difference equations, Partial--Numerical solutions ,01 natural sciences ,Domain (mathematical analysis) ,[SPI.MAT]Engineering Sciences [physics]/Materials ,Matemàtiques i estadística::Anàlisi numèrica [Àrees temàtiques de la UPC] ,0203 mechanical engineering ,65 Numerical analysis [Classificació AMS] ,Applied mathematics ,Polygon mesh ,0101 mathematics ,proper generalized decomposition ,Microscale chemistry ,Numerical Analysis ,Partial differential equation ,Applied Mathematics ,General Engineering ,time multiscale ,Finite element method ,Equacions diferencials parcials--solucions numèriques ,010101 applied mathematics ,Nonlinear system ,020303 mechanical engineering & transports ,Partition of unity ,partition of unity - proper generalized decomposition - time multiscale - Abstract
This is the peer reviewed version of the following article: Ibáñez, R. [et al.]. Multiscale proper generalized decomposition based on the partition of unity. "International journal for numerical methods in engineering", 9 November 2019, vol. 120, núm. 6, p. 727-747, which has been published in final form at DOI: 10.1002/nme.6154. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. Solutions of partial differential equations could exhibit a multiscale behavior. Standard discretization techniques are constraints to mesh up to the finest scale to predict accurately the response of the system. The proposed methodology is based on the standard proper generalized decomposition rationale; thus, the PDE is transformed into a nonlinear system that iterates between microscale and macroscale states, where the time coordinate could be viewed as a 2D time, representing the microtime and macrotime scales. The macroscale effects are taken into account because of an FEM-based macrodiscretization, whereas the microscale effects are handled with unidimensional parent spaces that are replicated throughout the domain. The proposed methodology can be seen as an alternative route to circumvent prohibitive meshes arising from the necessity of capturing fine-scale behaviors.
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