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El artículo presenta algunas reflexiones sobre los derechos humanos, la globalización y las TIC´S, como categorías catalizadoras de la homogenización de las estructuras sociales y normativas contemporáneas; asimismo, discurre en algunas relaciones de tensión que pueden darse entre ellas.

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This paper is dedicated to the effective viscosity of suspensions without inertia, at low solid volume fraction ϕ. The goal is to derive rigorously a o (ϕ 2) formula for the effective viscosity. In [17,19] , such formula was given for rigid spheres satisfying the strong separation assumption d m i n ≥ c ϕ − 1 3 r , where d m i n is the minimal distance between the spheres and r their radius. It was then applied to both periodic and random configurations with separation, to yield explicit values for the O (ϕ 2) coefficient. We consider here complementary (and certainly more realistic) random configurations, satisfying softer assumptions of separation, and long range decorrelation. We justify in this setting the famous Batchelor-Green formula [3]. Our result applies for instance to hardcore Poisson point process with almost minimal hardcore assumption d m i n > (2 + ε) r , ε > 0. [ABSTRACT FROM AUTHOR]

Copyright of Social Science Information is the property of Sage Publications, Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecologia Mediterranea is the property of Ecologia Mediterranea and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Some properties of electromagnetic metamaterials have been translated, using some wave analogies, to surface seismic wave control in sedimentary soils structured at the meter scale. Two large scale experiments performed in 2012 near the French cities of Grenoble [1] and Lyon [2] have confirmed the usefulness of this methodology and its potential influence on soil-structure interaction. We present here a new perspective on the in-situ experiment near Lyon, which unveils energy corridors in the seismic lens. We further introduce a concept of time-modulated seismic metamaterial underpined by an effective model based on Willis’s equations. As a first application, we propose that ambient seismic noise time-modulates structured soils that can be viewed as moving media. In the same spirit, a design of an analogous seismic computer is proposed making use of ambient seismic noise. We recall that ancient Roman theaters and forests of trees are two examples of large scale structures that behave in a way similar to electromagnetic metamaterials: invisibility cloaks and rainbows, respectively. Seismic metamaterials can thus not only be implemented for shielding, lensing and cloaking of potentially deleterious Rayleigh waves, but they also have potential applications in energy harvesting and analogous computations using ambient seismic noise, and this opens new vistas in seismic energy harvesting and conversion through the use of natural or artificial soil structuring. [ABSTRACT FROM AUTHOR]

This paper discusses the cultural changes brought about by the globalization processes by reviewing the homogenization-diversification dilemma that has dominated the debate in this field. To this end, the article examines the transformations that the expansion of the global capitalism has brought about in cultural frameworks, representations, and forms of symbolic consumption. The positions that argue that we are facing a process of cultural diversification thanks to the intensive exchange of messages and the flows of people will be reviewed, as well as those that state that the concentration of the production and distribution of symbolic goods in large corporations impoverishes imaginaries and reduces the richness of cultural frameworks. The intention of this reflection is to identify the limits of this disjunctive to move forward to more complex interpretative models, in accordance with the heterogeneity of the phenomena that are underway in the contemporary world. [ABSTRACT FROM AUTHOR]

Here, we present an overview of a first principles homogenization theory of periodic metamaterials. It is shown that in a rather general context it is possible to formally introduce effective parameters that describe the time evolution of macroscopic (slowly-varying in space) initial states of the electromagnetic field using an effective medium formalism. The theory is applied to different types of “wire metamaterials” characterized by a strong spatial dispersion in the long wavelength limit. It is highlighted that the spatial dispersion may tailor in unique ways the wave phenomena in wire metamaterials leading to exotic tunneling effects and broadband lossless anomalous dispersion. [ABSTRACT FROM AUTHOR]

We study the behavior of attractors of the reaction--diffusion equation in a perforated domain as the small parameter characterizing the perforation tends to zero. [ABSTRACT FROM AUTHOR]

Studies dedicated to the homogenization approach of microcracked media are largely focused on the determination of effective elastic properties. Some works investigate other properties, but most of them consider only open cracks. This paper intends to provide effective thermal properties related to the conduction problem taking into account the unilateral effect (opening/closure of cracks). Such analysis considers steady-state heat transfer within an initially isotropic media weakened by randomly oriented cracks. According to the boundary conditions, estimates and bounds based on Eshelby-like formalism are developed to derive closed-form expressions for effective thermal conductivity and resistivity in a fixed microcracking state. [ABSTRACT FROM AUTHOR]

Abstract In graphs, the concept of adjacency is clearly defined: it is a pairwise relationship between vertices. Adjacency in hypergraphs has to integrate hyperedge multi-adicity: the concept of adjacency needs to be defined properly by introducing two new concepts: k -adjacency – k vertices are in the same hyperedge – and e-adjacency – vertices of a given hyperedge are e-adjacent. In order to build a new e-adjacency tensor that is interpretable in terms of hypergraph uniformisation, we designed two processes: the first is a hypergraph uniformisation process (HUP) and the second is a polynomial homogeneisation process (PHP). The PHP allows the construction of the e-adjacency tensor while the HUP ensures that the PHP keeps interpretability. This tensor is symmetric and can be fully described by the number of hyperedges; its order is the range of the hypergraph, while extra dimensions allow to capture additional hypergraph structural information including the maximum level of k -adjacency of each hyperedge. Some results on spectral analysis are discussed. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article addresses the asymptotic response of viscoelastic heterogeneous media in the frequency domain, at high and low frequencies, for different types of elementary linear viscoelastic constituents. By resorting to stationary principles for complex viscoelasticity and adopting a classification of the viscoelastic behaviours based on the nature of their asymptotic regimes, either elastic or viscous, four exact relations are obtained on the overall viscoelastic complex moduli in each case. Two relations are related to the asymptotic uncoupled heterogeneous problems, while the two remaining ones result from the viscoelastic coupling that manifests itself in the transient regime. These results also provide exact conditions on certain integrals in time of the effective relaxation spectrum. This general setting encompasses the results obtained in preceding studies on mixtures of Maxwell constituents [1,2] . [ABSTRACT FROM AUTHOR]

In this paper, we consider a spectral problem with singular perturbation of density located near the boundary of the domain, depending on a small parameter. We prove the compactness theorem and study the behavior of eigenelements to the given problem, as the small parameter tends to zero. [ABSTRACT FROM AUTHOR]

The asphalt mixtures are composed of aggregates and asphalt used in the construction of the majority of roads. In order to ensure the sustainability of the infrastructures, the evaluation of the quality and the performances of these materials are essential. In this context, several researches have been focused on the development of predictive models, often empirical ones, in order to deduce the viscoelastic properties of an asphalt mixture based on the properties of its constituents (binder and/or aggregate). In this context, we suggest a homogenization model based on the generalized self-consistent scheme (GSC) to predict the complex module of the asphalt concrete from the properties of its components. In the aim of the approach validation, different types of mixtures (hot and warm) made in the laboratory were tested. The results showed that one can predict the complex modulus of the different types of asphalt concretes for temperatures less than 20 °C. However, beyond this temperature, the precision of the model decreases. Besides, the comparison of the micromechanical model with the rheologic models in literature showed that the suggested model can be also relevant in terms of predictions as the considered models. [ABSTRACT FROM AUTHOR]

We consider reaction–diffusion systems with randomly oscillating terms. We construct the deterministic homogenized reaction–diffusion system and prove that the trajectory attractors of the initial systems converge to the trajectory attractors of the homogenized systems. [ABSTRACT FROM AUTHOR]

In this contribution, numerical studies are carried-out in order to evaluate the elastic effective properties, including Young modulus, Poisson’s ratio, shear modulus and linear thermal expansion coefficient of composites reinforced by randomly distributed spherical particles. The spherical inclusion and matrix can be made from auxetic materials. In this numerical, the volumetric fraction of randomly uniform spherical inclusion can reach up to 60.27% of total volume. Different scenarii are carried-out to build graphical results that can suggest the designer to choose an appropriate combination of parameter to make the expected materials. [ABSTRACT FROM AUTHOR]

We consider a two-dimensional boundary value problems for the Helmholtz equation with Dirichlet and Neumann boundary conditions on a set of arcs. This set is obtained from a closed curve by cutting out small holes situated close to each other and having a locally periodic structure. We construct the asymptotics of the scattering frequencies (poles of the analytic continuation of solutions) with small imaginary parts, which converge to the square roots of multiple eigenvalues of limit problems. [ABSTRACT FROM AUTHOR]

We study the asymptotic behavior of solutions and eigenelements to a boundary value problem for the Laplace equation in a domain perforated along part of the boundary. On the boundary of holes, we set the homogeneous Dirichlet boundary condition and the Steklov spectral condition on the mentioned part of the outer boundary of the domain. Assuming that the boundary microstructure is periodic, we construct the limit problem and prove the homogenization theorem. [ABSTRACT FROM AUTHOR]

We analyze the transmission of sound through a sound hard film or layer with periodic subwavelength slits. For wavelength comparable to or larger than the slit spacing, the transmission spectra are revisited in terms of the transmission through an equivalent birefringent layer. It is shown that the Fano-type resonances can be understood by means of the dispersion relations of guided waves within the birefringent layer in the homogenized problem, equivalent to spoof plasmons for gratings. This is done by extending the homogenization to the evanescent waves being excited in the near field of the actual perforated layer. [ABSTRACT FROM AUTHOR]

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Matériaux et Techniques is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The relationship of social science and society is actively under discussion today in processes of social identity-making in the world at large. This article explores how, in different contexts, powerful institutions such as universities, disciplines, states, and more recently, a varied array of social movements struggle to define principles by which to determine which knowledge holders should be included, and on what terms, within social science. The analysis starts by reviewing the dominant discourse about academic social science and speculates on some of the factors influencing it, which are contingent upon the social relations and identities built around it in the setting of a powerful institution such as the university. Next it refers to the community of practice that grew around development thinking and practices since the early 20th century, mainly in governmental and nongovernmental institutions, aiming at social intervention. Finally, the analysis identifies the huge world expansion of social science in recent decades and its implications in the era of globalization. In view of persisting asymmetries and inequalities, this article asks about the possibility of alternative ways of practicing research. It suggests the need for a comparative frame that would foster organic interconnections between multiple voices and nourish a diversity of approaches. [ABSTRACT FROM PUBLISHER]

Homogenization estimates for viscoplastic polycrystals are derived by applying the generalized-secant linearization scheme of Liu and Ponte Castañeda (2004) [1] to the constitutive description with strain rates as primary variables. The resulting estimates are thus particularly suitable for simulating mechanical processes where deformations are imposed and where the material softens. Their accuracy is preliminarily assessed in the context of a model material system. Good agreement with previous estimates is found. [ABSTRACT FROM AUTHOR]

The consequences of globalization are a matter of debate. This study is an attempt to test the predictions of homogenization, polarization, and hybridization theorists with regard to the similarities and differences between and within societies. Utilizing four waves of the World Values Survey, from 1989 to 2007, this study covers 20 societies that represent 55% of the world population. The survey involved value statements in 72 areas by nationally representative samples. Results showed that differences between Western and non-Western countries’ cultures tended to increase slightly over time, but that these increases in disagreement were not due to cultures moving in opposite directions. In all instances, they were moving in the same direction, with one of the cultures moving faster. The direction of influence was mostly from Western toward non-Western, lending support to the idea that globalization leads to homogenization, rather than to polarization or hybridization. [ABSTRACT FROM AUTHOR]

Abstract: We investigate the boundary condition between a free fluid and a porous medium, where the interface between the two is given as a periodically curved structure. Using a coordinate transformation, we can employ methods of periodic homogenisation to derive effective boundary conditions for the transformed system. In the porous medium, the fluid velocity is given by Darcy's law with a non-constant permeability matrix. In tangential direction as well as for the pressure, a jump appears. Its magnitudes can be calculated with the help of a generalised boundary layer function. The results can be interpreted as a generalised law of Beavers and Joseph for curved interfaces. [Copyright &y& Elsevier]

Abstract: In this paper, we introduce a study that we carried out in order to validate the use of a simplified pregnant woman model for the assessment of the fetus exposure to radio frequency waves. This simplified model, based on the use of a homogeneous tissue to replace most of the inner organs of the virtual mother, would allow us to deal with many issues that are raised because of the lack of pregnant woman models for numerical dosimetry. Using specific absorption rate comparisons, we show that this model could be used to estimate the fetus exposure to plane waves. [Copyright &y& Elsevier]

Copyright of Nouvelles Perspectives en Sciences Sociales is the property of Editions Prise de parole and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: This Note presents criteria on the artificial compliance due to intrinsic cohesive zone models. A homogenized model is proposed for a collection of cohesive zones embedded between each mesh of a finite element-type discretization (cohesive-volumetric approach). The overall elastic behavior of this cohesive-volumetric medium is obtained as a function of the local properties and the mesh size. For an isotropic discretization, a criterion on the cohesive stiffnesses is derived: the additional compliance inherent to intrinsic cohesive zone models is bounded by lower value. [Copyright &y& Elsevier]

Abstract: We examine the band spectrum, and associated Floquet–Bloch eigensolutions, arising in a class of three-phase periodic checkerboards. On a periodic cell , the refractive index, n, is defined by with for , and for where is constant. We find that for the lowest frequency branch goes through origin with linear behaviour, which leads to effective properties encountered in most periodic structures. However, the case whereby is very unusual, as the frequency λ behaves like near the origin, where k is the wavenumber. Finally, when , the lowest branch does not pass through the origin and a zero-frequency band gap opens up. In the last two cases, effective medium theory breaks down even in the quasi-static limit, while the high-frequency homogenization [R.V. Craster, J. Kaplunov, A.V. Pichugin, High-frequency homogenization for periodic media, Proc. R. Soc. Lond. Ser. A 466 (2010) 2341–2362] neatly captures the detailed features of band diagrams. [Copyright &y& Elsevier]

Abstract: It is shown in this Note that the use of a 2D-interface model for the joints in the limit analysis of a structure made of bricks which are bounded with adhesively thin joints leads to an upper bound estimate of the bearing capacities of the structure, as the thickness of the joints goes to zero. Considering the compression in the vertical direction of a running bond masonry made of Drucker–Prager bricks and mortar, it is found that the use of the interface model overestimates by 15 percent the compressive strength of the masonry computed with 3D finite elements. Moreover, comparisons with compression test results show that the damaging behavior of the bricks has an important effect on the actual compressive strength of the masonry. [Copyright &y& Elsevier]

Abstract: For several years, measures to insure healthy river functions and to protect biodiversity have focused on management at the scale of drainage basins. Indeed, rivers bear witness to the health of their drainage basins, which justifies integrated basin management. However, this vision should not mask two other aspects of the protection of aquatic and riparian biodiversity as well as services provided by rivers. First, although largely depending on the ecological properties of the surrounding terrestrial environment, rivers are ecological systems by themselves, characterized by their linearity: they are organized in connected networks, complex and ever changing, open to the sea. Second, the structure and functions of river networks respond to manipulations of their hydrology, and are particularly vulnerable to climatic variations. Whatever the scale considered, river networks represent “hotlines” for sharing water between ecological and societal systems, as well as for preserving both systems in the face of global change. River hotlines are characterized by spatial as well as temporal legacies: every human impact to a river network may be transmitted far downstream from its point of origin, and may produce effects only after a more or less prolonged latency period. Here, I review some of the current issues of river ecology in light of the linear character of river networks. [Copyright &y& Elsevier]

The MOX fuel effective behavior in nominal pressure water reactor condition: Micro-mechanical modeling by non uniform transformation field analysis The heterogeneous distribution of the plutonium in the MOX nuclear fuel involves that the modeling of its behavior, under irradiation in pressure water reactor (PWR), is realized by the construction of macroscopic laws taking into account the microstructural effects. To homogenize this local problem, we chose a Non uniform Transformation Field Analysis (J.-C. Michel, P. Suquet, Int. J. Solids Struct. 40 (2003) 6937-6955). We thus present here, the works led on this model to adapt it to the MOX fuel behavior in PWR nominal conditions, as well as a comparison of the global and local results of this model to reference calculations. [ABSTRACT FROM AUTHOR]

Abstract: In this Note, we describe a homogenization methodology with the aim of establishing strain gradient constitutive relations for heterogeneous materials. The presented methodology includes two main steps. The first one is the construction of the average strain-energy density for a well-chosen Representative Volume Element (RVE) by using a homogenization technique. The second one is the transformation of the obtained average strain-energy density to that of the continuum. This transformation permits to ensure that the effective moduli do not depend on the size of an RVE, but only on the intrinsic size of the components. It also ensures that the moduli related to the strain gradient vanish as the contrast between the components disappears. These features were then illustrated by means of a simple example. [Copyright &y& Elsevier]

Abstract: In order to evaluate the stress-strain fields within periodic composites, finite element simulations are commonly performed on representative unit-cells. For flat composites, periodic boundary conditions are well established and widely used. In the present paper, the definition of periodic boundary conditions is extended to non-flat unit-cells in order to account for the radius of the tube in the simulation. Two different homogenization procedures, based on the simulations performed with these new boundary conditions, are then proposed in order to discuss the validity, as a function of the tube diameter, of a flat unit-cell approximation. [Copyright &y& Elsevier]

Abstract: In the context of inverse problems in mechanics, it is well known that the most typical situation is that neither the interior nor all the boundary is available to obtain data to detect the presence of inclusions or defects. We propose here an adaptive method that uses loads and measures of displacements only on part of the surface of the body, to detect defects in the interior of an elastic body. The method is based on Small Amplitude Homogenization, that is, we work under the assumption that the contrast on the values of the Lamé elastic coefficients between the defect and the matrix is not very large. The idea is that given the data for one loading state and one location of the displacement sensors, we use an optimization method to obtain a guess for the location of the inclusion and then, using this guess, we adapt the position of the sensors and the loading zone, hoping to refine the current guess. Numerical results show that the method is quite efficient in some cases, using in those cases no more than three loading positions and three different positions of the sensors. [Copyright &y& Elsevier]

The present work proposes a methodology for the study of carbon/carbon composites under dynamical stress and conditions of rubbing contact. It is based on the use of a finite-elements method (FEM) and a homogenization technique is applied to an elementary cell of the composite under contact condition. The comparison of random equivalent representative volume element underlines the importance to take into account the contact interface in such process. [ABSTRACT FROM AUTHOR]

Abstract: The strongly anisotropic rheology of olivine polycrystals, associated to their microstructure, constitutes a key feature affecting the dynamics of the Earth''s upper mantle. High pressure deformation experiments carried out on olivine single crystals under synchrotron radiation, together with estimations of lattice friction based on first-principle calculations, show a transition from easy [100] to easy [001] slips as pressure and temperature (thus depth) increases. We input these data at the slip system level into the second-order extension of the self-consistent scheme to assess microstructure evolution along a typical flow pattern beneath an oceanic spreading center. [Copyright &y& Elsevier]

Abstract: The behaviour of a free fluid flow above a porous medium, both separated by a curved interface, is investigated. By carrying out a coordinate transformation, we obtain the description of the flow in a domain with a straight interface. Using periodic homogenisation, the effective behaviour of the transformed partial differential equations in the porous part is given by a Darcy law with non-constant permeability matrix. Then the fluid behaviour at the porous-liquid interface is obtained with the help of generalised boundary-layer functions: Whereas the velocity in normal direction is continuous across the interface, a jump appears in tangential direction. Its magnitude seems to be related to the slope of the interface. Therefore the results indicate a generalised law of Beavers and Joseph. [Copyright &y& Elsevier]

Abstract: We study the solutions to quasilinear elliptic equations with high contrast coefficients. The energy formulation leads to work with variable exponent Lebesgue spaces in domains with a complex microstructure scaled by a small parameter ε. We derive rigorously the corresponding homogenized problem. It is completely described in terms of local energy characteristics of the original domain. To cite this article: C. Choquet, L. Pankratov, C. R. Mecanique 337 (2009). [Copyright &y& Elsevier]

Abstract: The purpose of this Note is the determination of the in-plane homogenized strength domain of a “quasi-periodic” masonry under the assumption of infinitely resistant blocks connected by cohesionless Mohr–Coulomb interfaces. This masonry is obtained by introducing a random perturbation on the horizontal width of the blocks of a periodic running bond masonry. It is found that in some non-trivial cases the strength domain coincides exactly with that of the initial periodic masonry. To cite this article: K. Sab, C. R. Mecanique 337 (2009). [Copyright &y& Elsevier]

Abstract: We study the determination of tensile strength of a sample consisting of a biphasic random material, for different proportions of components. To this end we apply a method of homogenization based on an assumption of perfect mix. The result is compared with strength derived from a calculation of probabilistic structure and strength observed in a numerical simulation on a large number of samples. This comparison highlights the interest of the homogenization method used and the relevance of the assumption of perfect mix. To cite this article: S. Turgeman, B. Guessab, C. R. Mecanique 337 (2009). [Copyright &y& Elsevier]

Abstract: We consider a formal asymptotic study of plates with periodically rapidly varying heterogeneities. The asymptotic analysis is performed when both the period of change of the material properties and the thickness of the plate are of the same orders of magnitude. We consider a plate made of Ciarlet–Geymonat type materials (P.G. Ciarlet and G. Geymonat (1982)). Depending on the order of magnitude of the applied loads, we obtain a nonlinear membrane model and a nonlinear membrane inextensional-bending model as announced in E. Pruchnicki (2006). Our approach is based on a sequence of recursive minimization problems. To cite this article: E. Pruchnicki, C. R. Mecanique 337 (2009). [Copyright &y& Elsevier]

Abstract: This Note presents a FFT based-method for obtaining the permeability of a periodic micro-porous medium. The periodic medium is constituted of a rigid solid matrix saturated by a viscous fluid. The flow obeys the Stokes equations and a slip condition at the surface of the rigid skeleton is considered. The permeability is obtained from the homogenization of periodic media and an extension of the FFT method used for composite elastic media. The incorporation of the slip condition is made through the introduction of an interphase between the fluid and the solid. The method of solution uses the classical expansion along Neumann series of the velocity field of the periodic problem and Green''s tensor in Fourier space. To cite this article: V. Monchiet et al., C. R. Mecanique 337 (2009). [Copyright &y& Elsevier]

Abstract: We study the asymptotic behavior, as , of solutions to a nonlinear elliptic equation with nonstandard growth condition in domains containing a grid-type microstructure that is concentrated in an arbitrary small neighborhood of a given hypersurface Γ. We assume that on , where is an unknown constant. The macroscopic equation and a nonlocal transmission condition on Γ are obtained by the variational homogenization technique in the framework of Sobolev spaces with variables exponents. This result is then illustrated by a periodic example. To cite this article: B. Amaziane et al., C. R. Mecanique 337 (2009). [Copyright &y& Elsevier]

Abstract: The high order homogenization technique generates the so called infinite order homogenized equation. Its coefficients were widely discussed in composite mechanics literature because they are closely related to the so called high order strain gradients theories. However, it was not clear what is the correct mathematical setting for this equation and what are the asymptotically exact boundary conditions. In the present Note we give a variational formulation for the high order homogenized equation by the projection of the initial problem on the “ansatz subspace”. This formulation generates the appropriate boundary conditions for the high order homogenized equation. The error estimates for the solution of the original problem and the homogenized one are obtained. To cite this article: G. Panasenko, C. R. Mecanique 337 (2009). [Copyright &y& Elsevier]

Copyright of Revue Anthropologie et Sociétés is the property of Anthropologie et Societies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: We derive a new yield function for materials containing spheroidal voids embedded in a perfectly-plastic anisotropic Hill-type matrix. Using approximate limit-analysis and a restricted set of trial velocity fields, analytical yield loci are derived for a hollow, spheroidal volume element containing a confocal spheroidal void. Alternatively, the yield loci are determined through numerical limit-analysis, i.e., employing a larger set of velocity fields. The numerical results are quasi-exact for transversely isotropic materials under axisymmetric loading. We show that an enhanced description of admissible microscopic deformation fields results in a close agreement between analytical and numerical macroscopic yield loci. To cite this article: S.M. Keralavarma, A.A. Benzerga, C. R. Mecanique 336 (2008). [Copyright &y& Elsevier]

Abstract: This Note deals with an optimization study for the representative elementary volume (REV) of the 3D orthogonal reinforcement in order to suggest the internal geometry of wicks as well as the prediction of mechanical and damage properties under axial loading. The applied method of optimization is the one of the sequential quadratic programming (SQP). The mechanical properties are determined by a homogenization study based on the average sum of the rigidities of the constituents and the composite resistance is searched starting from the application of the 3D Tsai-Wu failure criterion. The proposition of the weaving is spotted by the internal geometry represented by the fibers volume fractions, their proportions in each direction and the weaving step of the vertical reinforcement. The results of this study are compared to experimental studies about 3D orthogonal with carbon reinforcements. To cite this article: R. Younes et al., C. R. Mecanique 336 (2008). [Copyright &y& Elsevier]

Abstract: This paper is devoted to a micromechanics-based simulation of the response of concrete to hydrostatic and oedometric compressions. Concrete is described as a composite made up of a cement matrix in which rigid inclusions are embedded. The focus is put on the role of the interface between matrix and inclusion which represent the interfacial transition zone (ITZ). A plastic behavior is considered for both the matrix and the interfaces. The effective response of the composite is derived from the modified secant method adapted to the situation of imperfect interfaces. To cite this article: T.H. Le et al., C. R. Mecanique 336 (2008). [Copyright &y& Elsevier]