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Showing 1 to 20 of 34 for “"Rve"”.
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Strain inhomogeneities during plasticity and creep of metals: representative volume elements and microscale strain predictions
… strains primarily near grain boundaries was observed for all cases investigated, with no visible difference in the patterns of strain accumulation for creep and plasticity. In the second part of this work, the strain-based representative volume element (RVE) resulting from the plastic and creep …
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Concrete microstructure homogenization technique with application to model concrete serviceability
… Defined on a representative volume element (RVE), the relationship between microstructure and macro properties is established. The proposed model is validated by experimental results and then applied in the study of concrete serviceability. The concrete homogenization model includes RVE in …
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Power approximation for the test of study-level categorical moderators in meta-regression with dependent effect sizes
… model with robust variance estimation (CHE+RVE). Additionally, I conduct a Monte Carlo simulation to validate this power approximation formula against the true simulated power of a test of multiple contrasts from a CHE+RVE model. I also examine the Type I error rates and power of a test of …
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Micro-Mechanics Based Representative Volume Element Modeling Of Heterogeneous Cementitious Materials
… as a micro-scale representative volume element (RVE) in ABAQUS to generate cubes several tens of microns in dimension and subjected to various prescribed deformation modes to generate the effective elastic tensor of the material. The RVE-calculated elastic properties such as moduli and Poisson's …
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Scale-Dependent Homogenization and Scaling Laws in Random Polycrystals
… approach to the Representative Volume Element (RVE), the cornerstone of the separation of scales in continuum mechanics. The RVE is approached by setting up and solving stochastic Dirichlet and Neumann boundary value problems consistent with the Hill(-Mandel) macrohomogeneity condition. Further, …
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Scale-dependent homogenization of elastic-viscoelastic random composites
… scales of the continuum mechanical model d < L_{RVE} < L macro. Here L_{RVE} refers to the size of so-called Representative Volume Element (RVE), while d is the microstructural scale (microconstituents’ size) and Lmacro is the macroscale. In the randomly structured media, the RVE is considered to …
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Multiscale modelling and an experimental investigation on size-scale effects in concrete
… with a so-called Representative Volume Element (RVE) and are a statistical average. This concept is based on the presumption that the specimen size is much larger than the size of its constituents, so that the behaviour of a single constituent can be neglected. This presumption does not hold true …
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Homogenization and elastic-plastic transitions in random and FGM microstructures
… of the Representative Volume Element (RVE) that corresponds to the effective properties of materials. Microstructural randomness is inherent in these materials and hence we study the scaling from Statistical Volume Element (SVE) to RVE. Using Hill condition, the RVE is achieved when the …
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A study of the Segmental and Suprasegmental Phonology of Rhondda Valleys English
… and vowel systems of Rhondda Valleys English (RVE), with phonetic realizations and lexical incidence. Comparisons with British R.P. are made and similarities with neighbouring varieties of English (e.g. the West Country) and the Welsh Language are observed.<br/><br/>The suprasegmental …
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Modeling Microvoid Localization with Explicit Finite Element Analysis
… to single void representative volume elements (RVEs) under applied stress-states with moderate to large triaxialities. In this thesis, those limitations are largely overcome by solving microvoid localization problems with the explicit FEA method. A general framework for applying periodic …
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An efficient three-dimensional database driven approach for multi scale homogenization
… method assigns a representative volume element (RVE) of the materials microstructure at points across the macroscopic sample. This process results in the realization of a fully nested boundary value problem, where macroscopic quantities, required to model the structure, are obtained by …
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Constitutive modeling of the finite deformation behavior of membranes possessing a triangulated networked microstructure
… to identify a representative volume element (RVE) for the model. A strain energy density function in terms of an arbitrary planar deformation field is proposed using the RVE. Differentiation of the strain energy density function provides expressions for the general multiaxial stress-stretch …
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Experimental Characterization of Heterogeneous Deformation Due to Phase Transformations, Twinning, and Slip Deformation Using Digital Image Correlation
… sequence, nuances of the stress-strain curve such as strain hardening and softening, the hysteretic behavior, the strain-rate dependence, twinning strain, twin-twin intersections, twin fraction evolution, dynamic strain aging, grain interactions, mesoscopic slip bands, and a RVE size.
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Mechanical And Computational Evaluation Of Cementitious Materials With Hollow Glass Microsphere Inclusions
… element code. The representative volume element (RVE) in ABAQUS was a 100x100x100 μm3 cube. Since the symmetry as well as the anisotropy of the cementitious material system is not fully established, iso-strain based boundary conditions were applied to this RVE towards determining various elements …
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Investigative Application of the Intrinsic Extended Finite Element Method for the Computational Characterization of Composite Materials
… through a representative volume element (RVE), the filler agents are defined as individual weak bimaterial interfaces. Though a series of RVE studies, calculating the effective elastic material properties of carbon nanotube-epoxy nanocomposite systems, the benefits in substituting the …
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Entwicklung mechanischer Modelle zur analytischen Beschreibung der Materialeigenschaften von textilbewehrtem Feinbeton
… the concept of representative volume elements (RVE) is used. RVEs are representative for the mesoscopic structure. The overall material behaviour on the macroscopic level is obtained by means of homogenisation of the heterogeneous material behaviour on the mesoscopic level. Based on the micro …
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Avalanches, percolation, and stochastic damage evolution in disordered media
… below the representative volume element (RVE) size. The overarching theme of this dissertation is modeling apparent properties of disordered systems on sub-RVE lengthscales using numerical techniques that are based on an explicit representation of the material microstructure. The classical …
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Finite element analysis of shear resistant mechanisms for biolaminate interfaces
… on a microscopic representative volume element (RVE) of the fish scale with an overall thickness of 800 micron. The FEA RVE had one million uniform 8-micron cubical 8-node elements. The geometrically nonlinear sawtooth features are explicitly modeled. An elastic-plastic model described the …
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MACHINE LEARNING FOR CONSTITUTIVE MODELLING
… model is first trained based on a simplified RVE, followed by a refinement of surrogate model based on target data generated with detailed RVEs. This thesis shows that the proposed two strategies, EC and KT, can improve the off-line learning efficiency.
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Mesoscale random fields of stiffness for in-plane elasticity
… attainment of the representative volume element (RVE). Focusing on elastic moduli in particular, a micromechanical analysis based on the Hill-Mandel condition leads to the conclusion that two fields, stiffness and compliance, are required to bound the response of the material. Continuing the work …
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