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Showing 1 to 17 of 17 for “"VISCOELASTIC MODELS"”.
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Viscoelastic Models for Ligaments and Tendons
… tissues such as ligaments and tendons are viscoelastic materials. They exhibit a slow continuous increase in strain over time, or creep, when subjected to a constant stress and a slow continuous decrease in stress over time, or stress relaxation, when subjected to a constant strain. …
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Viscoelastic Fluid Modeling for Geophysical Applications in an Eulerian Framework
… on long timescales, motivating the use of viscoelastic models for intermediate regimes. Such models are essential for capturing both stress accumulation and permanent deformation but are highly nonlinear and numerically challenging. Classical approaches in geophysical viscoelastic modeling …
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Rheological Methods and Their Application To Biological Systems
… of methylation, and degree of blockiness on the viscoelastic properties of pectin are explored. Elastic and viscous properties of pectin are found to be negatively correlated with its degree of methylesterification, whilst elastic properties are positively correlated with its degree of …
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Long-term creep of encased polymer liners
… liner samples encased in steel pipes. Several viscoelastic models were investigated in order to fit the data. The data is used to predict the long-term modulus used in design. (Abstract shortened by UMI.).
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Modeling and analysis of all-season passenger car tire using finite element analysis
… various temperatures and analyzed using hyper-viscoelastic models. The tire-road characteristics including rolling resistance, cornering characteristics, and traction are explained and investigated.
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A viscoelastic hydrodynamic approach to the density fluctuations in classical liquids
… regime. Specifically, in this work, a viscoelastic hydrodynamic approach is proposed to describe the density fluctuations in supercooled liquids in the generalized hydrodynamic regime. Based on the generalization of the Navier-Stokes stress-strain constitutive relation, the viscoelastic …
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The influence of time-dependent material behavior on the response of sandwich beams
… segmented reflectors, simple sandwich beam models are developed. The beam models included layers representing face sheets, core and adhesive. The issue of time-dependency is essential because the expected life of a reflector is on the order of 20 years. Using the principle of stationary …
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Measuring The Nanomechanics Of Nanoconfined Water Layers
… The results were analyzed with the help of two viscoelastic models, the Kelvin model and the Maxwell model. The stiffness and damping coefficient oscillate with period 2.7 ± 0.8 Å below 1 nm thickness of the water film. The retardation time and the relaxation time were measured as a function of …
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A Non-linear Visco-elastic Model for Dynamic Finite Element Simulation of Bovine Cortical Bone
… and Bekker et al. developed three-dimensional models, but do not accurately capture the transition in behaviour in the intermediate strain rate region, while Cloete et al. developed a phenomenological model which captures the intermediate strain rate behaviour in one dimension. This work aims …
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Time-dependent assessment of the human lumbar spine in response to flexion exposures: in vivo measurement and modeling
… risk of LBDs. Trunk flexion can result in viscoelastic deformations of soft tissues and subsequent mechanical and neuromuscular alterations of the trunk, and may thereby increase LBD risk. While viscoelastic behaviors of isolated spinal motion segments and muscles have been extensively …
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Single Cell Biomechanical Phenotyping using Microfluidics and Nanotechnology
… also considered the application of nonlinear viscoelastic models such as Fractional Zener and Generalized Maxwell models for the naturally complex, heterogeneous, and nonlinear structure of living cells. The emerging need for a high-throughput clinically relevant alternative for evaluating …
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Thixotropic-viscoelastic rheological fingerprints in large amplitude oscillatory shear
… to characterize the behavior of constitutive models that exhibit both thixotropic and viscoelastic phenomena. We demonstrate this use of LAOS by first examining the strain controlled LAOS (LAOStrain) response of a Thixoelastic Jeffreys model. First, this canonical model is defined for …
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Bio-inspired Cellulose Nanocomposites
… process of the three different polymers. Two viscoelastic models, namely Johannsmann and Voigt, were respectively used to calculate the areal mass and thickness of the adsorbed layers. Atomic force microscopy studies showed a complete coverage of the surface with lignin in all the disposition …
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Methods for the integrated design of viscoelastic materials and structural geometry
… However, allowing complex materials (e.g., viscoelastic materials and soft solids) as options for system materials can eliminate some associated limitations on design freedom. Furthermore, designing material characteristics may open up avenues to unprecedented designs with optimal materials. …
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Development of an efficient finite volume computational platform for the simulation of complex flows of complex fluids governed by the Rolie-Poly model
… Polymer melts are a category of fluids known as viscoelastic fluids and it is only recently that different forms of constitutive equations derived as simplified versions of molecular reptation-based models have been developed to describe molten polymers. The most adept mathematical models being …
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Finite element simulation of viscoelastic flow: effect of the rheological model and the mesh
The numerical simulation of viscoelastic flows was studied in this work. In particular the effect of mesh refinement on the quality and the convergence of the finite element method was examined, as well as the differences that may be found by using several rheological models to describe the …
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ΚΡΙΤΗΡΙΑ ΙΞΩΔΟΕΛΑΣΤΙΚΗΣ ΣΥΖΕΥΞΗΣ ΜΑΚΡΩΝ ΟΣΤΩΝ ΚΑΙ ΟΣΤΙΚΟΥ ΤΣΙΜΕΝΤΟΥ
… BONE-CEMENT, IS THE UNSUITABLE MATCHING OF THEIR VISCOELASTIC PROPERTIES. IN THE PRESENT STUDY, THE VISCOELASTIC BEHAVIOUR OF FRESH LONG BONES IS EXAMINED, AND IT IS COMPARED TO THE RESPECTIVE BEHAVIOUR OF BONE-CEMENT. WITHIN THIS FRAMEWORK, THE STATIC AND THE CREEP BEHAVIOUR OF WHOLE FRESH SHEEP …