Non-Gaussian Entanglement and Wigner Function

A measure of non-Gaussian entanglement in continuous variable (CV) systems based on the volume of the negative part of the Wigner function is proposed. We analyze comparatively this quantity with a numerical evaluation of the negativity of the partial transpose (NPT) considering a system of Bell states formed in the coherent state basis (quasi-Bell states)

A minimally-intrusive fully 3D separated plate formulation in computational structural mechanics

Most of mechanical systems and complex structures exhibit plate and shell components. Therefore, 2D simulation, based on plate and shell theory, appears as an appealing choice in structural analysis as it allows reducing the computational complexity. Nevertheless, this 2D framework fails for capturing rich physics compromising the usual hypotheses considered when deriving standard plate and shell theories. To circumvent, or at least alleviate this issue, authors proposed in their former works an in-plane–out-of-plane separated representation able to capture rich 3D behaviors while keeping the computational complexity the one of 2D simulations. In the present paper we propose an efficient integration of fully 3D descriptions into existing plate software

Application of PGD separation of space to create a reduced-order model of a lithium-ion cell structure

Lithium-ion cells can be considered a laminate of thin plies comprising the anode, separator, and cathode. Lithium-ion cells are vulnerable toward out-of-plane loading. When simulating such structures under out-of-plane mechanical loads, subordinate approaches such as shells or plates are sub-optimal because they are blind toward out-of-plane strains and stresses. On the other hand, the use of solid elements leads to limitations in terms of computational efficiency independent of the time integration method. In this paper, the bottlenecks of both (implicit and explicit) methods are discussed, and an alternative approach is shown. Proper generalized decomposition (PGD) is used for this purpose. This computational method makes it possible to divide the problem into the characteristic in-plane and out-of-plane behaviors. The separation of space achieved with this method is demonstrated on a static linearized problem of a lithium-ion cell structure. The results are compared with conventional solution approaches. Moreover, an in-plane/out-of-plane separated representation is also built using proper orthogonal decomposition (POD). This simply serves to compare the in-plane and out-of-plane behaviors estimated by the PGD and does not allow computational advantages relative to conventional techniques. Finally, the time savings and the resulting deviations are discussed

Le treebank comme outil de description pour les langues orales : le cas de l’arabe tunisien

International audienceLa constitution et l’enrichissement d’un corpus est une tâche délicate, surtout quand il s’agitd’une langue privée de ressources et d’outils qui en facilitent le traitement. Nous nousreposons dans cette communication sur l’exposition de la situation de la plupart des parlersmaghrébins à travers l’exemple de la réalisation d’un petit treebank issu d’un corpuséchantillonné et diversifié d’environ 13 heures d’enregistrements de l’arabe tunisien effectués,à Orléans et en Tunisie, dans le cadre d’une étude doctorale (Ben Barka Messaoudi, 2022). Ils’agira de présenter ce type de ressources et leur apport en tant qu'outils de description del’oral et des phénomènes liés à l’oralité, notamment les chevauchements, les coénonciations etle codeswitchin

Le treebank comme outil de description pour les langues orales : le cas de l’arabe tunisien

International audienceLa constitution et l’enrichissement d’un corpus est une tâche délicate, surtout quand il s’agitd’une langue privée de ressources et d’outils qui en facilitent le traitement. Nous nousreposons dans cette communication sur l’exposition de la situation de la plupart des parlersmaghrébins à travers l’exemple de la réalisation d’un petit treebank issu d’un corpuséchantillonné et diversifié d’environ 13 heures d’enregistrements de l’arabe tunisien effectués,à Orléans et en Tunisie, dans le cadre d’une étude doctorale (Ben Barka Messaoudi, 2022). Ils’agira de présenter ce type de ressources et leur apport en tant qu'outils de description del’oral et des phénomènes liés à l’oralité, notamment les chevauchements, les coénonciations etle codeswitchin

Non-Gaussian states with strong positive partial transpose

We consider the problem of entanglement criteria in non-Gaussian systems, providing a necessary and sufficient condition of separability of non-Gaussian states based on strong positive partial transpose (SPPT) of the corresponding density matrices. The separability conditions of states generated by photon subtraction from vacuum squeezed states are given

Regularization of shear banding and prediction of size effects in manufacturing operations: A micromorphic plasticity explicit scheme

International audienceAbstract Good quality manufacturing operation simulations are essential to obtain reliable numerical predictions of the processes. In many cases, it is possible to observe that the deformation localizes in narrow areas, and since the primary deformation mode is under shear, these areas are called shear bands . In classical continuum mechanics models, the deformation localization may lead to spurious mesh dependency if the material locally experiences thermal or plastic strain softening. One option to regularize such a non-physical behavior is to resort to non-local continuum mechanics theories. This paper adopts a scalar micromorphic approach, which includes a characteristic length scale in the constitutive framework to enforce the plastic strain gradient theory to regularize the solution. Since many manufacturing process simulations are often assessed through finite element methods with an explicit solver to facilitate convergence, we present an original model formulation and procedure for the implementation of the micromorphic continuum in an explicit finite element code. The approach is illustrated in the case of the VPS explicit solver from ESI GROUP. According to the original formulation, we propose an easy way to implement a scalar micromorphic approach by taking advantage of an analogy with the thermal balance equation. The numerical implementation is verified against the analytical solution of a semi-infinite glide problem. Finally, the correctness of the method is addressed by successfully predicting size effects both in a cutting and a bending tests