bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship between raised BMI and sugar sweetened beverage and high fat food consumption among children
Authors: Millar Lynne , Rowland Bosco , Nichols Melanie , Swinburn Boyd , Bennett Catherine , Skouteris Helen , Allender Steven 
Published: November 2013

ObjectiveLongitudinal evidence of relationships between unhealthy diets and BMI in children is crucial for appropriately targeting obesity prevention activities. The objective was to determine the relationship between frequency of consumption of sugar sweetened beverages (SSBs) and high fat foods (HFFs) and body weight in Australian children aged from 4 to 10 years.MethodsData from 4,164 children participating in four waves (wave 1, 2004; wave 2, 2006; wave 3, 2008; and wave 4, 2010) of the Longitudinal Study of Australian Children were analyzed. A multi‐level growth model tested relationships between consumption of SSB and HFF and BMI z‐scores.ResultsBMI z‐scores were associated with daily consumption of HFF, SSB and maternal BMI independent of BMI z‐scores at wave 1 (baseline); with each additional occurrence of SSB and HFF consumption intake per day, BMI z‐score increased by 0.015 U (P < 0.01) and 0.014 U (P < 0.001), respectively. With each additional maternal BMI unit, BMI z‐score increased by 0.032 (P < 0.001).ConclusionsHigher BMI z‐scores were strongly associated with the consumption of SSBs and HFFs. Future efforts to prevent obesity should consider urgent action to address the impact of the consumption of SSBs and HFFs in childhood.
Nanomechanics of Carbon Nanotubes
Authors: Sun Y.W. , Dunstan D.J. , Hartmann M.A. , Holec D. 
Published: November 2013

AbstractWe discuss the mechanical properties of carbon nanotubes, in particular the pressure‐dependence of the Raman modes and the collapse pressure, and their relation to the corresponding mechanical properties of graphite and graphene. The frequencies of the Raman G‐mode and radial breathing mode (RBM), as well as the pressure dependence of the RBM can be largely‐explained in the existing framework of C–C stretching modes and envirionmental effects induced by the pressure medium. The pressure dependence of the G‐mode is still missing such an explanation. The collapse pressure can be understood in terms of the continuum theory for thin‐walled tubes. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Micromechanical Simulation of the Hall‐Petch Effect with a Crystal Gradient Theory including a Grain Boundary Yield Criterion
Authors: Wulfinghoff Stephan , Bayerschen Eric , Böhlke Thomas 
Published: November 2013

AbstractA viscoplastic strain gradient crystal plasticity theory based on the gradient of the equivalent plastic strain ∇γeq is proposed. A grain boundary yield condition is introduced. The microstructural explanation of the Hall‐Petch effect, accounting for notch‐like stress concentrations at the grain boundary as a result of discrete slip bands, is reviewed. Periodic tensile test FEM simulation results illustrate the prediction of the numerical model. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modelbased Investigations of Gyroscopic Effect on the (Elasto‐)Kinematics of Suspension Systems
Authors: Kohl Sergej , Zuber Armin , Sextro Walter 
Published: November 2013

AbstractDuring wheel bumping caused by stochastic road excitation, the wheel performs rotational and translational movements. The bump and rebound wheel velocity leads to significant angular velocities based on the (elasto‐)kinematics of the suspension system. Based on the gyroscopic effect, moments arise about the rotating wheel induced by the angular change while bumping. Therefore it leads to undesirable wheel changes and degrades the tire contact and finally decreases the driving stability. A flexible MBS‐model of the five‐link rear axle system that includes these effects has been built up to allow a detailed investigation of the gyroscopic effect. Using the simulation results, conclusions can be drawn for refining design criteria for the kinematics, elastokinematics and topology of the suspension system to increase the active safety of the vehicle. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Computing time investigations for variational multirate integration
Authors: Gail Tobias , Leyendecker Sigrid , Ober‐Blöbaum Sina 
Published: November 2013

AbstractConsider a mechanical system that contains slow and fast dynamics. Let it be possible, to split the potential energy into a slow and a fast potential and the configuration vector into slow and fast variables. For such systems, multirate schemes simulate the different parts using different time steps with the goal to save computing time. For the proposed multirate scheme, a time grid consisting of micro and macro nodes is used and the integrator is derived from a discrete variational principle. Variational integrators conserve properties like symplecticity and momentum maps and have good energy behavior. To solve the resulting system of coupled nonlinear equations, a Newton‐Raphson iteration with an analytical Jacobian is used. It is demonstrated that the multirate approach leads to less computing time compared to singlerate simulation by means of three example systems, the Fermi‐Pasta‐Ulam problem, a triple spherical pendulum and a simple atomistic model, where the latter two are subject to constraints. Computing times are compared for different numbers of micro and macro nodes for dynamic simulations during a certain time interval. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Parametric frequency analysis of oscillatory behavior of mouse Zona Pellucida spherical net model: cases of successful and of unsuccessful fertilization
Authors: Hedrih Andjelka , Lazarevic Mihailo , Mitrovic‐Jovanovic Ana 
Published: November 2013

AbstractThe current paper proposes a model for describing mechanical phenomena that occur during the process of mammal fertilization when spermatozoa impact the surface of Zona Pellucida. Zona pellucida (ZP) is a dynamical 3D matrix that surrounds the mammalian oocyte. In the process of fertilization, sperm cell has to penetrate this structure. To describe impact of sperm cells with velocities that are effective and those that are ineffective relative to the oscillatory behavior of ZP, the discreet continuum model in the form of spherical net model is used. Resultant trajectories of knot mass particles dynamics of mouse ZP spherical net model in the form of generalized Lussajous curves are presented. Using generalized Lussajous curves, parametric frequency analysis of oscillatory behavior of knot material particles in the mouse ZP spherical net model is conducted. The influence of impact angles of sperm cells on corresponding knot mass particle trajectory is discussed. Favorable and unfavorable trajectories of knot mass particle motions are discussed in the context of successful fertilization. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the treatment of active behaviour in continuum muscle mechanics
Authors: Heidlauf Thomas , Röhrle Oliver 
Published: November 2013

AbstractTwo approaches of including active contractile behaviour of muscle tissue written in a continuum‐mechanical formulation are presented. One approach relies on the addition of active and passive stress contributions, while the other approach is based on a multiplicative decomposition of the deformation gradient tensor. Both formulations can be stated in a thermodynamically consistent manner, each with different constraints, and both models can reproduce experimental data of passive and fully active muscle. Different behaviours are observed when comparing the active muscle models at submaximal stimulation rates. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Phase Field Approach for Dynamic Fracture
Authors: Kuhn Charlotte , Schlüter Alexander , Müller Ralf 
Published: November 2013

AbstractIn phase field fracture models cracks are indicated by the value of a scalar field variable which interpolates smoothly between broken and undamaged material. The evolution equation for this crack field is coupled to the mechanical field equations in order to model the mutual interaction between the crack evolution and mechanical quantities. In finite element simulations of crack growth at comparatively slow loading velocities, a quasi‐static phase field model yields reasonable results. However, the simulation of fast loading or the nucleation of new cracks challenges the limits of such a formulation. Here, the quasi‐static phase field model predicts brutal crack extension with an artificially high crack speed. In this work, we analyze to which extend a dynamic formulation of the mechanical part of the phase field model can overcome this paradox created by the quasi‐static formulation. In finite element simulations, the impact of the dynamic effects is studied, and differences between the crack propagation behavior of the quasi‐static model and the dynamic formulation are highlighted. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical modelling of local‐global buckling mode interaction of sandwich struts
Authors: Völlmecke Christina , Müller Wolfgang H. 
Published: November 2013

AbstractA numerical approach simulating the effects of coupled local‐global mode interaction on the postbuckling of axially compressed sandwich beam columns is presented. The formulation is based on the weak form of the balance of linear momentum whilst large strains are considered. An open source software is used to solve the formulation and results are presented showing good phenomenological agreement with analytically derived solutions. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the folding of plates which buckle before and beyond the elastic limit
Authors: Müller Bernhard , Schagerl Martin , Schöder Kai‐Uwe 
Published: November 2013

AbstractSimply supported rectangular elasto‐plastic plates which are uniformly compressed buckle either before or beyond the elastic limit. Consequently, the post critical behaviour, the position of first membrane yield and folding mode differ significantly whether buckling happens before or beyond the elastic limit. A distinct folding‐line perpendicular to the loading direction develops only for plates which buckle beyond the elastic limit. This article analysis the post‐buckling behaviour and the folding mode of uniformly compressed plates and points out the correlation to the folding mode of axially crushed profiles. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A new method for the connection of non‐conforming NURBS patches in isogeometric analysis
Authors: Dornisch Wolfgang , Klinkel Sven 
Published: November 2013

AbstractThe main objective of isogeometric analysis is the use of one common data set for design and analysis. Geometrical models usually consist of multiple NURBS surface patches with non‐matching parametrizations along common edges. The ability to handle non‐conforming meshes is essential for isogeometric finite element systems to avoid manipulations of the geometry model. In general two possible strategies exist. The first one is to enhance the weak form of the potential with additional terms to constrain the deformations of adjacent edges to be equal, e.g. with the Lagrange Multiplier method. The second one is to establish a relation between the deformations of adjacent patches. Thus, superfluous degrees of freedom are condensated out of the system and the patches are connected naturally by shared degrees of freedom. No alteration of the weak form is necessary which simplifies the implementation in existing finite element systems. For adjacent edges with hierarchic knot vectors an analytical solution exists. In the general case of non‐hierarchic knot vectors it is not possible to find an analytical solution. This contribution presents a new numerical method to establish this relation. A collocation along the connection line links the deformations of adjacent patches. A theoretical derivation of the method is given and the choice of the collocation points is investigated. Numerical studies compare the new method with the Lagrange Multiplier method and show its applicability. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modellierung der Bewegung von Wasserrinnsalen auf Zylinderoberflächen in Interaktion mit der Luftumströmung
Authors: Seidel Christian , Dinkler Dieter 
Published: November 2013

AbstractDie Beweglichkeit von Wasserrinnsalen auf Zylinderoberflächen besitzt beim hydroaeroelastischen Phänomen der Regen‐Wind induzierten Schwingungen, welches bei geneigten Kabeln und Hängern von Schrägkabelbrücken und Bogenbrücken durch gleichzeitiges Auftreten von Regen und Wind entstehen kann, eine elementare Bedeutung für den Erregermechanismus [1]. Bei der Untersuchung des Schwingungsphänomens ist bei der Modellierung der Rinnsale neben der Beschreibung ihrer Beweglichkeit auch die genaue Kenntnis ihrer Gleichgewichtslagen auf der Zylinderoberfläche wichtig. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Constitutive modeling of cyclic stress softening in filled elastomers
Authors: Khiêm Vu Ngoc , Dargazany Roozbeh , Itskov Mikhail 
Published: November 2013

AbstractQuasi‐static cyclic loading tests on filled rubber‐like materials reveal a significant stress softening in the first cycle. The magnitude of this softening, widely known as the Mullins effect, reduces in the next cycles until it reaches a stabilized value referred to as hysteresis. In this contribution, we associate the hysteresis with the fracture of carbon bonds in the filler network. In order to calculate the cyclic energy dissipation, we modify the classic concept of network decomposition [1, 2] and add a new network considered to be responsible for the breakage and re‐formation of carbon black aggregates during loading and unloading. The proposed model is in‐line with a wide range of experimental observations. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Computation of energy dissipation in visco‐elastic materials at finite deformation
Authors: Behnke Ronny , Kaliske Michael 
Published: November 2013

AbstractIn this contribution, the derivation of the energy dissipation rate in generalized visco‐elastic material models with internal stress‐type variables and linear evolution equations is outlined. The approximated dissipation rate is computed from a positive quadratic form of the nonlinear non‐equilibrium stresses and the inverse of the consistent material tangent tensor. The presented method is used to compute the energy dissipation of visco‐elastic rubber material in a large scale application of a steady state rolling tire structure. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Finite Element Simulation of Steel Solidification under High Temperature
Authors: Moj Lukas , Ricken Tim , Göhler Klaus 
Published: November 2013

AbstractFinite element simulation of hot working of steel has gained significant importance in steel industries. The aim of describing such processes using the finite element method is to predict phenomena like shrinkage during solidification. Due to this thermo‐mechanical behaviour residual stresses appear, which cause cracks and the final steel slab loses its required properties as a result. We propose a two‐phase incompressible model based on the Theory of Porous Media (TPM) for a numerical description of steelmaking processes. A thermo‐mechanical coupling is required to model a high temperature‐dependency. In order to consider thermal expansion of solid, a multiplicative decomposition of the deformation gradient into a mechanical and a thermal part has been applied. The Von Mises J2 plasticity with isotropic hardening criterion has been selected for the solid‐phase of the model. Representative numerical examples, as well as the influence of single material parameters on the model will be shown. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Phase Field Approach for Martensitic Transformations in Elastoplastic Materials
Authors: Schmitt Regina , Müller Ralf , Skorupski Robert , Smaga Marek , Eifler Dietmar 
Published: November 2013

AbstractA multivariant phase field model for martensitic transformations in elastoplastic materials is introduced which is in mathematical terms the regularization of a sharp interface approach. The evolution of microstructure is assumed to follow a time dependent Ginzburg‐Landau equation. The coupled problem of the mechanical balance equation and the evolution equations is solved using finite elements and an implicit time integration scheme. In this work, plasticity is considered for the austenitic phase which influences the martensitic evolution. With aid of the model these interactions are studied in detail. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simulation of a membrane flow interaction by an iteration based on a panel method
Authors: Steinrück Herbert , Müllner Markus 
Published: November 2013

AbstractA flow structure interaction of a membrane and a fluid is investigated. A conventional segregated numerical algorithm, where the membrane deformation and the flow dynamics are calculated alternately has to fail due to the artificial added mass instability. Thus, a new iteration scheme is proposed. In order to get a good prediction for the deformation of the membrane, the equations describing the membrane are coupled to a potential flow solver (panel method). Then a CFD solver can be used to determine the corrections of the flow field due viscosity and turbulence. An example is presented that this procedure seems to be numerically stable. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermodynamically consistent temperature prediction in dissipative solids
Authors: Bartels Alexander , Mosler Jörn 
Published: November 2013

AbstractThe present work deals with the thermomechanical coupling in dissipative solids and the consistent temperature prediction. One of the first works dealing with this subject was written by Taylor & Quinney (TQ) where the fraction between dissipated energy eventually transformed to heat and plastic work is assumed as constant (typically between 0.8‐1.0 for metals). Although this assumption often leads to reasonable temperature predictions, it is not always in agreement with experimental observations. Furthermore, the TQ model does not comply with the first and second law of thermodynamics in general. Unfortunately, a standard thermodynamically consistent framework is not convincing either, since it usually leads to a significant overprediction of the temperature increase during dissipative processes. Within the present work, a novel framework suitable for the modeling of thermomechanically coupled processes is discussed. It will be shown that this framework is thermodynamically consistent and leads to a temperature increase, as a result of plastic deformation, in good agreement with the underlying experiments. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical Model for Electro‐Mechanical Analysis Based on Finite Element Method
Authors: Abdelhakim Lotfi 
Published: November 2013

AbstractIn this paper, we present a numerical procedure that can be used to model the electro‐mechanical coupled behavior of the dielectric actuator domain. The equation describing the electrostatical part is given by the reduced form of the Maxwell equation and the electrostatic potential [1]. The mechanical problem is described by the constitutive equations and equilibrium equations. Using the finite element method, this technique is to divide a whole problem into sub‐problems. The complexity of the original problem is therefore reduced by focusing only on the most relevant areas. A finite element analysis is then performed by applying the electrostatic Maxwell pressure as Neumann boundary conditions to compute the displacements. Once the displacement is computed, the electrostatic domain or the conductor is updated. Electrostatic analysis is performed on the updated geometry and the finite element method is then used to determine the change in potential due to geometric perturbations. Once the surface charge densities are known, the new electrostatic Maxwell pressure is computed. The mechanical and electrostatic analysis is repeated until an equilibrium state is computed. The procedure is demonstrated in the paper by the solution of some two‐dimensional and three‐dimensional problems. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Higher Dimensional Continuum Dislocation Dynamics Theory: A Runge‐Kutta Discontinuous Galerkin Approach
Authors: Thawinan Ekkachai , Wieners Christian , Sandfeld Stefan 
Published: November 2013

AbstractThe reformulation in conservative form of the higher‐dimensional continuum dislocations dynamics(hdCDD) theory of Hochrainer (Ph.D. thesis, 2006) is presented together with a framework for elasto‐plasticity problem based on this theory. A Runge‐Kutta discontinuous Galerkin(RKDG) method is used for the evolution of hdCDD to obtain information of the micro‐structure which is coupled with a finite element method for the stress computation. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Die Flachwassergleichung und ihre Anwendung auf die Untersuchung von Wasserkraftwerken
Authors: Ostermann Lars , Seidel Christian 
Published: November 2013

AbstractFlachwassergleichungen finden eine breite Anwendung bei der Untersuchung strömungsmechanischer Fragestellungen im Wasserbau. Im Rahmen der Entwicklung eines Forschungswasserkraftwerks wurde für die numerische Simulation ein Modell auf der Basis von Flachwassergleichungen mit Berücksichtigung von Sohl‐ und Wandreibung mit der Manning‐Zahl entwickelt, mit dem sowohl die Kraftwerksströmung als auch der Einfluss der Wasserkraftanlage und ihres Betriebes auf den lokalen Flussabschnitt untersucht werden kann. Die Diskretisierung der Flachwassergleichung erfolgt mit dem Finite‐Volumen‐Verfahren, wobei der Flussvektor mit dem HLL‐MUSCL‐Ansatz berechnet wird. Ziel der Untersuchungen ist, das Langzeitverhalten der Kraftwerksströmung zu simulieren. Die Diskretisierung des Berechnungsgebietes als unstrukturiertes Dreiecksnetz erfolgt mit einem iterativen, optimierten Netzgenerator für beliebige Gebiete mit lokaler Netzverfeinerung. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simulation of the turbulent flow in a model hydraulic spool valve
Authors: Schümichen Michel , Joppa Matthias , Rüdiger Frank , Fröhlich Jochen , Müller Lutz , Weber Jürgen , Helduser Siegfried 
Published: November 2013

AbstractThe paper presents results of the simulation of the flow in a model hydraulic spool valve by means of Large Eddy Simulation (LES). The flow is characterized by a very low Reynolds number which is untypical for LES. The emphasis of the study is the analysis of the flow and the investigation of the influence of the subgrid‐scale model. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mathematical Modeling of Combustion of Single Porous Pulverized Coal Particle Using Lattice Approach
Authors: Jovanović Rastko , Rašuo Boško , Erić Milić , Cvetinović Dejan , Stefanović Predrag 
Published: November 2013

AbstractNovel model of coal particle combustion was developed. The aim of proposed model is to describe all possible mechanisms for particle combustion and their sensitivity to combustion conditions. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)