[hal-01111126] How the augmented Lagrangian algorithm can deal with an infeasible convex quadratic optimization problem

This paper analyses the behavior of the augmented Lagrangian algorithm when it deals with an infeasible convex quadratic optimization problem. It is shown that the algorithm finds a point that, on the one hand, satisfies the constraints shifted by the smallest possible shift that makes them feasible and, on the other hand, minimizes the objective on the corresponding shifted constrained set. The speed of convergence to such a point is globally linear, with a rate that is inversely proportional to the augmentation parameter. This suggests us a rule for determining the augmentation parameter that aims at controlling the speed of convergence of the shifted constraint norm to zero; this rule has the advantage of generating bounded augmentation parameters even when the problem is infeasible.



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[hal-01138472] Espejeos : une lecture plastique de l’œuvre de Rosario Ferré par María Renati

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[hal-01133858] Numerical simulation of two-phase multicomponent flow with reactive transport in porous media: application to geological sequestration of CO2

In this work, we consider two-phase multicomponent flow in heterogeneous porous media with chemical reactions. Equations governing the system are the mass conservation law for each species, together with Darcy's law and complementary equations such as the capillary pressure law. Coupling with chemistry occurs through reactions rates. These rates can either be given non-linear functions of concentrations in the case of kinetic chemical reactions or are unknown in the case of equilibrium chemical reactions (such as reactions in aqueous phase). In this latter case, each reaction gives rise to a mass action law, an algebraic relation that relates the activities of the implied species. The resulting system will couple partial differential equations with algebraic equations. The aim of this paper is to develop a numerical method for the simulation of this system. We consider a sequential approach that consists in splitting the initial problem into two subsystems. The first subsystem is a two-phase two-component flow, while the second subsystem is devoted to a reactive transport problem. For the two-phase two-component flow part, we have used an already existing module of the open-source parallel multiphase flow simulator DuMu X. To solve the reactive transport problem, we have implemented a new module in the DuMu X framework that solves a single phase multicomponent transport problem, and we have coupled it with a locally developed code for chemical equilibrium, called ChemEqLib, through a sequential iterative approach. Then, both modules have been coupled to propose a simple, but mathematically consistent, iterative method that handles two-phase flow with reactive transport. The approach is validated on a 2D example from the literature representative of a model for the long-term fate of sequestered CO 2 .



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[hal-01137507] Robust bladder image registration by redefining data-term in total variational approach

Cystoscopy is the standard procedure for clinical diagnosis of bladder cancer diagnosis. Bladder carcinoma in situ are often multifocal and spread over large areas. In vivo, localization and follow-up of these tumors and their nearby sites is necessary. But, due to the small field of view (FOV) of the cystoscopic video images, urologists cannot easily interpret the scene. Bladder mosaicing using image registration facilitates this interpretation through the visualization of entire lesions with respect to anatomical landmarks. The reference white light (WL) modality is affected by a strong variability in terms of texture, illumination conditions and motion blur. Moreover, in the complementary fluorescence light (FL) modality, the texture is visually different from that of the WL. Existing algorithms were developed for a particular modality and scene conditions. This paper proposes a more general on fly image registration approach for dealing with these variability issues in cystoscopy. To do so, we present a novel, robust and accurate image registration scheme by redefining the data-term of the classical total variational (TV) approach. Quantitative results on realistic bladder phantom images are used for verifying accuracy and robustness of the proposed model. This method is also qualitatively assessed with patient data mosaicing for both WL and FL modalities.



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[hal-01138468] Seule soumise les voix elle consentait. Le rêve choral de Sor Juana Inés de la Cruz

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[hal-01138125] Rapport final du projet « Villes en Transition : le cas du quartier de de la Fontaine d’Ouche à Dijon

Comment mobiliser les citoyens autours de conduites éco-responsables en matière de consommation ? Nous avons souhaité, au travers de l’appel à projet MOVIDA, identifier les leviers d’une consommation plus durable en les situant dans une dynamique territoriale observée à l’échelle d’un ou plusieurs petits territoires, qui seront autant de terrains d’expérimentation. Cette démarche, qui articule plusieurs approches disciplinaires, entend éclairer les dimensions psycho-sociologiques et communicationnels de la consommation sans négliger les aspects géographiques et économiques. Notre hypothèse est la suivante : Les habitants des quartiers urbains dits sensibles manifestent des formes particulières de résilience par rapport aux problèmes rencontrés dans le cadre de la transition écologique, résilience dont les solutions concrètes résulteront de moyens d’accompagnement et de mobilisation innovants, qu’ils soient technologiques, organisationnels ou communicationnels.



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[hal-01137507] Robust bladder image registration by redefining data-term in total variational approach

Cystoscopy is the standard procedure for clinical diagnosis of bladder cancer diagnosis. Bladder carcinoma in situ are often multifocal and spread over large areas. In vivo, localization and follow-up of these tumors and their nearby sites is necessary. But, due to the small field of view (FOV) of the cystoscopic video images, urologists cannot easily interpret the scene. Bladder mosaicing using image registration facilitates this interpretation through the visualization of entire lesions with respect to anatomical landmarks. The reference white light (WL) modality is affected by a strong variability in terms of texture, illumination conditions and motion blur. Moreover, in the complementary fluorescence light (FL) modality, the texture is visually different from that of the WL. Existing algorithms were developed for a particular modality and scene conditions. This paper proposes a more general on fly image registration approach for dealing with these variability issues in cystoscopy. To do so, we present a novel, robust and accurate image registration scheme by redefining the data-term of the classical total variational (TV) approach. Quantitative results on realistic bladder phantom images are used for verifying accuracy and robustness of the proposed model. This method is also qualitatively assessed with patient data mosaicing for both WL and FL modalities.



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[hal-01138125] Rapport final du projet « Villes en Transition : le cas du quartier de de la Fontaine d’Ouche à Dijon

Comment mobiliser les citoyens autours de conduites éco-responsables en matière de consommation ? Nous avons souhaité, au travers de l’appel à projet MOVIDA, identifier les leviers d’une consommation plus durable en les situant dans une dynamique territoriale observée à l’échelle d’un ou plusieurs petits territoires, qui seront autant de terrains d’expérimentation. Cette démarche, qui articule plusieurs approches disciplinaires, entend éclairer les dimensions psycho-sociologiques et communicationnels de la consommation sans négliger les aspects géographiques et économiques. Notre hypothèse est la suivante : Les habitants des quartiers urbains dits sensibles manifestent des formes particulières de résilience par rapport aux problèmes rencontrés dans le cadre de la transition écologique, résilience dont les solutions concrètes résulteront de moyens d’accompagnement et de mobilisation innovants, qu’ils soient technologiques, organisationnels ou communicationnels.



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[hal-01138467] Du bolivarisme au bolivarianisme, 1812-2012

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[in2p3-01088477] Large scale distribution of ultra high energy cosmic rays detected at the Pierre Auger Observatory with zenith angles up to 80$^\circ$

We present the results of an analysis of the large angular scale distribution of the arrival directions of cosmic rays with energy above 4 EeV detected at the Pierre Auger Observatory including for the first time events with zenith angle between $60^\circ$ and $80^\circ$. We perform two Rayleigh analyses, one in the right ascension and one in the azimuth angle distributions, that are sensitive to modulations in right ascension and declination, respectively. The largest departure from isotropy appears in the $E > 8$ EeV energy bin, with an amplitude for the first harmonic in right ascension $r_1^\alpha =(4.4 \pm 1.0){\times}10^{-2}$, that has a chance probability $P(\ge r_1^\alpha)=6.4{\times}10^{-5}$, reinforcing the hint previously reported with vertical events alone.



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[cea-01135502] Radiation magnetohydrodynamics in global simulations of protoplanetary discs

Aims. Our aim is to study the thermal and dynamical evolution of protoplanetary discs in global simulations, including the physics of radiation transfer and magneto-hydrodynamic turbulence caused by the magneto-rotational instability.Methods. We have developed a radiative transfer method based on the flux-limited diffusion approximation that includes frequency dependent irradiation by the central star. This hybrid scheme is implemented in the PLUTO code. The focus of our implementation is on the performance of the radiative transfer method. Using an optimized Jacobi preconditioned BiCGSTAB solver, the radiative module is three times faster than the magneto-hydrodynamic step for the disc set-up we consider. We obtain weak scaling efficiencies of 70% up to 1024 cores.Results. We present the first global 3D radiation magneto-hydrodynamic simulations of a stratified protoplanetary disc. The disc model parameters were chosen to approximate those of the system AS 209 in the star-forming region Ophiuchus. Starting the simulation from a disc in radiative and hydrostatic equilibrium, the magneto-rotational instability quickly causes magneto-hydrodynamic turbulence and heating in the disc. We find that the turbulent properties are similar to that of recent locally isothermal global simulations of protoplanetary discs. For example, the rate of angular momentum transport α is a few times 10-3. For the disc parameters we use, turbulent dissipation heats the disc midplane and raises the temperature by about 15% compared to passive disc models. The vertical temperature profile shows no temperature peak at the midplane as in classical viscous disc models. A roughly flat vertical temperature profile establishes in the optically thick region of the disc close to the midplane. We reproduce the vertical temperature profile with viscous disc models for which the stress tensor vertical profile is flat in the bulk of the disc and vanishes in the disc corona.Conclusions. The present paper demonstrates for the first time that global radiation magneto-hydrodynamic simulations of turbulent protoplanetary discs are feasible with current computational facilities. This opens up the window to a wide range of studies of the dynamics of the inner parts of protoplanetary discs, for which there are significant observational constraints.



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[hal-01138467] Du bolivarisme au bolivarianisme, 1812-2012

[...]



from HAL : Dernières publications http://ift.tt/19Jfamc

[in2p3-01088477] Large scale distribution of ultra high energy cosmic rays detected at the Pierre Auger Observatory with zenith angles up to 80$^\circ$

We present the results of an analysis of the large angular scale distribution of the arrival directions of cosmic rays with energy above 4 EeV detected at the Pierre Auger Observatory including for the first time events with zenith angle between $60^\circ$ and $80^\circ$. We perform two Rayleigh analyses, one in the right ascension and one in the azimuth angle distributions, that are sensitive to modulations in right ascension and declination, respectively. The largest departure from isotropy appears in the $E > 8$ EeV energy bin, with an amplitude for the first harmonic in right ascension $r_1^\alpha =(4.4 \pm 1.0){\times}10^{-2}$, that has a chance probability $P(\ge r_1^\alpha)=6.4{\times}10^{-5}$, reinforcing the hint previously reported with vertical events alone.



from HAL : Dernières publications http://ift.tt/1tQYCfY

[cea-01135502] Radiation magnetohydrodynamics in global simulations of protoplanetary discs

Aims. Our aim is to study the thermal and dynamical evolution of protoplanetary discs in global simulations, including the physics of radiation transfer and magneto-hydrodynamic turbulence caused by the magneto-rotational instability.Methods. We have developed a radiative transfer method based on the flux-limited diffusion approximation that includes frequency dependent irradiation by the central star. This hybrid scheme is implemented in the PLUTO code. The focus of our implementation is on the performance of the radiative transfer method. Using an optimized Jacobi preconditioned BiCGSTAB solver, the radiative module is three times faster than the magneto-hydrodynamic step for the disc set-up we consider. We obtain weak scaling efficiencies of 70% up to 1024 cores.Results. We present the first global 3D radiation magneto-hydrodynamic simulations of a stratified protoplanetary disc. The disc model parameters were chosen to approximate those of the system AS 209 in the star-forming region Ophiuchus. Starting the simulation from a disc in radiative and hydrostatic equilibrium, the magneto-rotational instability quickly causes magneto-hydrodynamic turbulence and heating in the disc. We find that the turbulent properties are similar to that of recent locally isothermal global simulations of protoplanetary discs. For example, the rate of angular momentum transport α is a few times 10-3. For the disc parameters we use, turbulent dissipation heats the disc midplane and raises the temperature by about 15% compared to passive disc models. The vertical temperature profile shows no temperature peak at the midplane as in classical viscous disc models. A roughly flat vertical temperature profile establishes in the optically thick region of the disc close to the midplane. We reproduce the vertical temperature profile with viscous disc models for which the stress tensor vertical profile is flat in the bulk of the disc and vanishes in the disc corona.Conclusions. The present paper demonstrates for the first time that global radiation magneto-hydrodynamic simulations of turbulent protoplanetary discs are feasible with current computational facilities. This opens up the window to a wide range of studies of the dynamics of the inner parts of protoplanetary discs, for which there are significant observational constraints.



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[hal-01138466] Contactos y desencuentros. Unas calas en los personajes femeninos de la ficción puertorriqueña actual

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[hal-01138466] Contactos y desencuentros. Unas calas en los personajes femeninos de la ficción puertorriqueña actual

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[in2p3-01077217] Of Contact Interactions and Colliders

The hierarchy of scales which would allow dimension-six contact interactions to parametrise New Physics may not be verified at colliders. Instead, we explore the feasability and usefulness of parametrising the high-energy tail of distributions at the LHC using form factors. We focus on the process pp -> l+l- in the presence of t (or s)-channel New Physics, guess a form factor from the partonic cross-section, and attempt to use data to constrain its coefficients, and the coefficients to constrain models. We find that our choice of form factor decribes t-channel exchange better than a contact interaction, and the coefficients in a particular model can be obtained from the partonic cross-section. We estimate bounds on the coefficients by fitting the form factors to available data. For the parametrisation corresponding to the contact interaction approximation, our expected bounds on the scale $\Lambda$ are within ~ 15% of the latest limits from the LHC experiments.



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[hal-01138464] Oblivionalia

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[in2p3-01077217] Of Contact Interactions and Colliders

The hierarchy of scales which would allow dimension-six contact interactions to parametrise New Physics may not be verified at colliders. Instead, we explore the feasability and usefulness of parametrising the high-energy tail of distributions at the LHC using form factors. We focus on the process pp -> l+l- in the presence of t (or s)-channel New Physics, guess a form factor from the partonic cross-section, and attempt to use data to constrain its coefficients, and the coefficients to constrain models. We find that our choice of form factor decribes t-channel exchange better than a contact interaction, and the coefficients in a particular model can be obtained from the partonic cross-section. We estimate bounds on the coefficients by fitting the form factors to available data. For the parametrisation corresponding to the contact interaction approximation, our expected bounds on the scale $\Lambda$ are within ~ 15% of the latest limits from the LHC experiments.



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[hal-01138464] Oblivionalia

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