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1

A Four-Dimensional Viscoelastic Deformation Model For Long Valley...  

Open Energy Info (EERE)

and components of two continuous GPS time series. Additionally, the model explains the spatial extent of deformation observed by InSAR data covering the 1997-98 inflation...

2

A theory of finite deformation magneto-viscoelasticity  

E-Print Network [OSTI]

This paper deals with the mathematical modelling of large strain magneto-viscoelastic deformations. Energy dissipation is assumed to occur both due to the mechanical viscoelastic effects as well as the resistance offered by the material to magnetisation. Existence of internal damping mechanisms in the body is considered by decomposing the deformation gradient and the magnetic induction into `elastic' and `viscous' parts. Constitutive laws for material behaviour and evolution equations for the non-equilibrium fields are derived that agree with the laws of thermodynamics. To illustrate the theory the problems of stress relaxation, magnetic field relaxation, time dependent magnetic induction and strain are formulated and solved for a specific form of the constitutive law. The results, that show the effect of several modelling parameters on the deformation and magnetisation process, are illustrated graphically.

Saxena, Prashant; Steinmann, Paul

2015-01-01T23:59:59.000Z

3

Non-linear viscoelastic deformation of polymeric solutions  

E-Print Network [OSTI]

NON-LINEAR VISCOELASTIC DEFORMATION OF POLYMERIC SOLUTIONS A Thesis by JAVIER SANCHEZ REYES Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... December 2000 Major Subject: Chemical Engineering NON-LINEAR VISCOELASTIC DEFORMATION OF POLYMERIC SOLUTIONS A Thesis by JAVIER SANCHEZ REYES Submitted to Texas A&M University in partial fulfillment of the requirements for the degree of MASTER...

Sanchez Reyes, Javier

2000-01-01T23:59:59.000Z

4

Viscoelastic Models of Tidally Heated Exomoons  

E-Print Network [OSTI]

Tidal heating of exomoons may play a key role in their habitability, since the elevated temperature can melt the ice on the body even without significant solar radiation. The possibility of life is intensely studied on Solar System moons such as Europa or Enceladus, where the surface ice layer covers tidally heated water ocean. Tidal forces may be even stronger in extrasolar systems, depending on the properties of the moon and its orbit. For studying the tidally heated surface temperature of exomoons, we used a viscoelastic model for the first time. This model is more realistic than the widely used, so-called fixed Q models, because it takes into account the temperature dependency of the tidal heat flux, and the melting of the inner material. With the use of this model we introduced the circumplanetary Tidal Temperate Zone (TTZ), that strongly depends on the orbital period of the moon, and less on its radius. We compared the results with the fixed Q model and investigated the statistical volume of the TTZ usi...

Dobos, Vera

2015-01-01T23:59:59.000Z

5

Viscoelastic fluid flow in a 2D channel bounded above by a deformable finite thickness elastic wall  

E-Print Network [OSTI]

The steady flow of three viscoelastic fluids (Oldroyd-B, FENE-P, and Owens model for blood) in a two-dimensional channel, partly bound by a deformable, finite thickness neo-Hookean solid, is computed. The limiting Weissenberg number beyond which computations fail to converge is found to increase with increasing dimensionless solid elasticity parameter {\\Gamma}, following the trend Owens > FENE- P > Oldroyd-B. The highly shear thinning nature of Owens model leads to the elastic solid always collapsing into the channel, for the wide range of values of {\\Gamma} considered here. In the case of the FENE-P and Oldroyd-B models, however, the fluid-solid interface can be either within the channel, or bulge outwards, depending on the value of {\\Gamma}. This behaviour differs considerably from predictions of earlier models that treat the deformable solid as a zero-thickness membrane, in which case the membrane always lies within the channel. The capacity of the solid wall to support both pressure and shear stress, in c...

Chakraborty, Debadi

2015-01-01T23:59:59.000Z

6

Kinetic viscoelasticity modeling applied to degradation during carbon–carbon composite processing  

E-Print Network [OSTI]

Kinetic viscoelasticity modeling has been successfully utilized to describe phenomena during cure of thermoset based carbon fiber reinforced matrices. The basic difference from classic viscoelasticity is that the fundamental ...

Drakonakis, Vassilis M.

7

On models for viscoelastic fluid-like materials that are mechanically incompressible and  

E-Print Network [OSTI]

On models for viscoelastic fluid-like materials that are mechanically incompressible and thermally of the full Navier­Stokes­Fourier system. J. Math. Fluid Mech., 11:274­302, 2009 Mechanically incompressible;Viscoelastic fluids ­ Maxwell model F l lsld µm m Mechanical analogue: Spring ­ energy storage. Dashpot

Cerveny, Vlastislav

8

Micromechanical modeling of deployment and shape recovery of thin-walled viscoelastic composite space  

E-Print Network [OSTI]

Micromechanical modeling of deployment and shape recovery of thin-walled viscoelastic composite;Micromechanical Modeling of Deployment and Shape Recovery of Thin-walled Viscoelastic Composite Space Structures of the paper presents an experimental study of the deployment and shape recovery of composite tape

Pellegrino, Sergio

9

Protein viscoelastic dynamics: a model system  

E-Print Network [OSTI]

A model system inspired by recent experiments on the dynamics of a folded protein under the influence of a sinusoidal force is investigated and found to replicate many of the response characteristics of such a system. The essence of the model is a strongly over-damped oscillator described by a harmonic restoring force for small displacements that reversibly yields to stress under sufficiently large displacement. This simple dynamical system also reveals unexpectedly rich behavior, exhibiting a series of dynamical transitions and analogies with equilibrium thermodynamic phase transitions. The effects of noise and of inertia are briefly considered and described.

Craig Fogle; Joseph Rudnick; David Jasnow

2015-02-02T23:59:59.000Z

10

Characterization of asphalt concrete using anisotropic damage viscoelastic-viscoplastic model  

E-Print Network [OSTI]

model developed at the Texas Transportation Institute (TTI) is improved and used to model the irrecoverable strain component. The influence of the anisotropic aggregate distribution is accounted for in both the viscoelastic and viscoplastic responses. A...

Abdel-Rahman Saadeh, Shadi

2007-04-25T23:59:59.000Z

11

Finite Element Modeling of Drilling Using DEFORM  

E-Print Network [OSTI]

Vijayaraghavan, A. (2005), “Drilling of Fiber- ReinforcedFINITE ELEMENT MODELING OF DRILLING USING DEFORM J. Gardner,of Comprehensive Drilling Simulation Tool” ABSTRACT DEFORM-

Gardner, Joel D.; Dornfeld, David

2006-01-01T23:59:59.000Z

12

Micro-macro models for viscoelastic fluids: modelling, mathematics and numerics  

E-Print Network [OSTI]

This paper is an introduction to the modelling of viscoelastic fluids, with an emphasis on micro-macro (or multiscale) models. Some elements of mathematical and numerical analysis are provided. These notes closely follow the lectures delivered by the second author at the Chinese Academy of Science during the Workshop "Stress Tensor Effects on Fluid Mechanics", in January 2010.

C. Le Bris; T. Lelièvre

2011-02-01T23:59:59.000Z

13

A Micromechanical Model for Viscoelastic-Viscoplastic Analysis of Particle Reinforced Composite  

E-Print Network [OSTI]

This study introduces a time-dependent micromechanical model for a viscoelastic-viscoplastic analysis of particle-reinforced composite and hybrid composite. The studied particle-reinforced composite consists of solid spherical particle and polymer...

Kim, Jeong Sik

2011-02-22T23:59:59.000Z

14

Non-Linear Drying Diffusion and Viscoelastic Drying Shrinkage Modeling in Hardened Cement Pastes  

E-Print Network [OSTI]

modeling with an average diffusion coefficient and with determined viscoelastic parameters from creep tests agreed well compared to the shrinkage data from experiments, indicating that drying shrinkage of cement paste may be considered as a poroviscoelastic...

Leung, Chin K.

2010-07-14T23:59:59.000Z

15

Deformable human body model development  

SciTech Connect (OSTI)

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). A Deformable Human Body Model (DHBM) capable of simulating a wide variety of deformation interactions between man and his environment has been developed. The model was intended to have applications in automobile safety analysis, soldier survivability studies and assistive technology development for the disabled. To date, we have demonstrated the utility of the DHBM in automobile safety analysis and are currently engaged in discussions with the U.S. military involving two additional applications. More specifically, the DHBM has been incorporated into a Virtual Safety Lab (VSL) for automobile design under contract to General Motors Corporation. Furthermore, we have won $1.8M in funding from the U.S. Army Medical Research and Material Command for development of a noninvasive intracranial pressure measurement system. The proposed research makes use of the detailed head model that is a component of the DHBM; the project duration is three years. In addition, we have been contacted by the Air Force Armstrong Aerospace Medical Research Laboratory concerning possible use of the DHBM in analyzing the loads and injury potential to pilots upon ejection from military aircraft. Current discussions with Armstrong involve possible LANL participation in a comparison between DHBM and the Air Force Articulated Total Body (ATB) model that is the current military standard.

Wray, W.O.; Aida, T.

1998-11-01T23:59:59.000Z

16

Modeling of quasistatic and dynamic load responses of filled viscoelastic materials  

E-Print Network [OSTI]

are typically used for static finite element analysis (see [9]). The CRSC/Lord team worked, both theoreticallyModeling of quasi­static and dynamic load responses of filled viscoelastic materials H.T. Banks factors to the complications arising in the process of formulating models. Damping is highly complex

17

Force-free swimming of a model helical flagellum in viscoelastic fluids  

E-Print Network [OSTI]

Force-free swimming of a model helical flagellum in viscoelastic fluids Bin Liua,1 , Thomas R. Powersa,b , and Kenneth S. Breuera a School of Engineering, Box D, Brown University, Providence, RI 02912 fluids. The fluids are highly viscous to replicate the low Reynolds number environment of microorgan

Thomases, Becca

18

Analytical Model of Tidal Distortion and Dissipation for a Giant Planet with a Viscoelastic Core  

E-Print Network [OSTI]

We present analytical expressions for the tidal Love numbers of a giant planet with a solid core and a fluid envelope. We model the core as a uniform, incompressible, elastic solid, and the envelope as a non-viscous fluid satisfying the $n=1$ polytropic equation of state. We discuss how the Love numbers depend on the size, density, and shear modulus of the core. We then model the core as a viscoelastic Maxwell solid and compute the tidal dissipation rate in the planet as characterized by the imaginary part of the Love number $k_2$. Our results improve upon existing calculations based on planetary models with a solid core and a uniform ($n=0$) envelope. Our analytical expressions for the Love numbers can be applied to study tidal distortion and viscoelastic dissipation of giant planets with solid cores of various rheological properties, and our general method can be extended to study tidal distortion/dissipation of super-earths.

Storch, Natalia I

2015-01-01T23:59:59.000Z

19

Modelling Viscoelastic Behaviour of Polymer by A Mixed Velocity, Displacement Formulation - Numerical and Experimental Results  

SciTech Connect (OSTI)

The objective of this work is to model the viscoelastic behaviour of polymer from the solid state to the liquid state. With this objective, we perform experimental tensile tests and compare with simulation results. The chosen polymer is a PMMA whose behaviour depends on its temperature. The computation simulation is based on Navier-Stokes equations where we propose a mixed finite element method with an interpolation P1+/P1 using displacement (or velocity) and pressure as principal variables. The implemented technique uses a mesh composed of triangles (2D) or tetrahedra (3D). The goal of this approach is to model the viscoelastic behaviour of polymers through a fluid-structure coupling technique with a multiphase approach.

Pham, VT.; Silva, L.; Digonnet, H.; Combeaud, C.; Billon, N.; Coupez, T. [Centre for Material Forming (CEMEF), MINES ParisTech, Rue Claude Daunesse, Sophia Antipolis cedex (France)

2011-05-04T23:59:59.000Z

20

Thermo-Viscoelastic-Viscoplastic-Viscodamage-Healing Modeling of Bituminous Materials: Theory and Computation  

E-Print Network [OSTI]

……………… ……… 341 9.6. Extrapolation of the Rutting in 3D.……....………… 348 9.7. Comparison with Experimental Results.….………… 351 9.8. Conclusions………………………………………… 354 xviii CHAPTER Page X CONCLUSIONS AND RECOMMENDATIONS..…………… 356 10... prediction using viscoelastic- viscoplastic model and experimental data for the cyclic stress control test at 19oC when the stress amplitude is 750kPa. (a) Loading cycles 1-30; (b) Loading cycles 970-980……………….. 268 7.36 Comparison of the VE...

Darabi Konartakhteh, Masoud

2012-10-19T23:59:59.000Z

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Viscoelastic Model for Lung Parenchyma for Multi-Scale Modeling of Respiratory System, Phase II: Dodecahedral Micro-Model  

SciTech Connect (OSTI)

In the first year of this contractual effort a hypo-elastic constitutive model was developed and shown to have great potential in modeling the elastic response of parenchyma. This model resides at the macroscopic level of the continuum. In this, the second year of our support, an isotropic dodecahedron is employed as an alveolar model. This is a microscopic model for parenchyma. A hopeful outcome is that the linkage between these two scales of modeling will be a source of insight and inspiration that will aid us in the final year's activity: creating a viscoelastic model for parenchyma.

Freed, Alan D.; Einstein, Daniel R.; Carson, James P.; Jacob, Rick E.

2012-03-01T23:59:59.000Z

22

Hyperbolic reformulation of a 1D viscoelastic blood flow model and ADER finite volume schemes  

SciTech Connect (OSTI)

The applicability of ADER finite volume methods to solve hyperbolic balance laws with stiff source terms in the context of well-balanced and non-conservative schemes is extended to solve a one-dimensional blood flow model for viscoelastic vessels, reformulated as a hyperbolic system, via a relaxation time. A criterion for selecting relaxation times is found and an empirical convergence rate assessment is carried out to support this result. The proposed methodology is validated by applying it to a network of viscoelastic vessels for which experimental and numerical results are available. The agreement between the results obtained in the present paper and those available in the literature is satisfactory. Key features of the present formulation and numerical methodologies, such as accuracy, efficiency and robustness, are fully discussed in the paper.

Montecinos, Gino I.; Müller, Lucas O.; Toro, Eleuterio F.

2014-06-01T23:59:59.000Z

23

Thermomechanical Constitutive Modeling of Viscoelastic Materials undergoing Degradation  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . 17 2. Constitutive assumptions . . . . . . . . . . . . . . . . 20 3. Reduction of the model to one dimensional Burg- ers? model . . . . . . . . . . . . . . . . . . . . . . . . . 24 D. Model 2... . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 1. Preliminaries . . . . . . . . . . . . . . . . . . . . . . . 27 2. Constitutive assumptions . . . . . . . . . . . . . . . . 30 3. Reduction of the model to one dimensional Burg- ers? model . . . . . . . . . . . . . . . . . . . . . . . . . 32...

Karra, Satish

2012-07-16T23:59:59.000Z

24

Decoherence of spin-deformed bosonic model  

SciTech Connect (OSTI)

The decoherence rate and some parameters affecting it are investigated for the generalized spin-boson model. We consider the spin-bosonic model when the bosonic environment is modeled by the deformed harmonic oscillators. We show that the state of the environment approaches a non-linear coherent state. Then, we obtain the decoherence rate of a two-level system which is in contact with a deformed bosonic environment which is either in thermal equilibrium or in the ground state. By using some recent realization of f-deformed oscillators, we show that some physical parameters strongly affect the decoherence rate of a two-level system. -- Highlights: •Decoherence of the generalized spin-boson model is considered. •In this model the environment consists of f-oscillators. •Via the interaction, the state of the environment approaches non-linear coherent states. •Effective parameters on decoherence are considered.

Dehdashti, Sh., E-mail: shahram.dehdashti@gmail.com [Department of Physics, Faculty of Science, University of Isfahan, Hezar Jerib St., Isfahan 81746-73441 (Iran, Islamic Republic of); Mahdifar, A., E-mail: mahdifar_a@sci.sku.ac.ir [Science Department, Shahrekord University, Shahrekord (Iran, Islamic Republic of); Bagheri Harouni, M., E-mail: m-bagheri@phys.ui.ac.ir [Department of Physics, Faculty of Science, University of Isfahan, Hezar Jerib St., Isfahan 81746-73441 (Iran, Islamic Republic of); Quantum Optics Group, Department of Physics, Faculty of Science, University of Isfahan, HezarJerib St., Isfahan 81746-73441 (Iran, Islamic Republic of); Roknizadeh, R., E-mail: rokni@sci.ui.ac.ir [Department of Physics, Faculty of Science, University of Isfahan, Hezar Jerib St., Isfahan 81746-73441 (Iran, Islamic Republic of); Quantum Optics Group, Department of Physics, Faculty of Science, University of Isfahan, HezarJerib St., Isfahan 81746-73441 (Iran, Islamic Republic of)

2013-07-15T23:59:59.000Z

25

Two- and Three-Dimensional Microstructural Modeling of Asphalt Particulate Composite Materials using a Unified Viscoelastic-Viscoplastic-Viscodamage Constitutive Model  

E-Print Network [OSTI]

The main objective of this study is to develop and validate a framework for microstructural modeling of asphalt composite materials using a coupled thermo-viscoelastic, thermo-viscoplastic, and thermo-viscodamage constitutive model. In addition...

You, Taesun

2013-08-13T23:59:59.000Z

26

Deformable Models & Applications Department of Computer Science  

E-Print Network [OSTI]

Deformable Models & Applications (Part I) Ye Duan Department of Computer Science University of Missouri at Columbia December 21, 2004 Ye Duan Department of Computer Science University of Missouri at Columbia December 21, 2004 University of Missouri at ColumbiaDepartment of Computer Science #12;Department

Duan, Ye

27

Competitive Mixture of Deformable Models for Pattern Classification \\Lambda  

E-Print Network [OSTI]

Competitive Mixture of Deformable Models for Pattern Classification \\Lambda Kwok­Wai Cheung Dit to pattern classification. Recently, we have cast a deformable model under a Bayesian framework for classification, giving promising results. However, deformable model methods are computation­ ally expensive due

Yeung, Dit-Yan

28

Start-up flow of a viscoelastic fluid in a pipe with fractional Maxwell's model  

E-Print Network [OSTI]

Unidirectional start-up flow of a viscoelastic fluid in a pipe with fractional Maxwell's model is studied. The flow starting from rest is driven by a constant pressure gradient in an infinite long straight pipe. By employing the method of variable separations and Heaviside operational calculus, we obtain the exact solution, from which the flow characteristics are investigated. It is found that the start-up motion of fractional Maxwell's fluid with parameters $\\alpha$ and $\\beta$, tends to be at rest as time goes to infinity, except the case of $\\beta=1$. This observation, which also can be predicted from the mechanics analogue of fractional Maxwell's model, agrees with the classical work of Friedrich and it indicates fractional Maxwell's fluid presents solid-like behavior if $\\be\

Di Yang; Ke-Qin Zhu

2010-06-27T23:59:59.000Z

29

Spatially resolved measurements of kinematics and flow-induced birefringence in worm-like micellar solutions undergoing high rate deformations  

E-Print Network [OSTI]

Worm-like micellar solutions are model non-Newtonian systems on account of their well understood linear viscoelastic behavior. Their high deformation rate, non-linear rheological response, however, remains inadequately ...

Ober, Thomas J. (Thomas Joseph)

2010-01-01T23:59:59.000Z

30

Modeling of the Aging Viscoelastic Properties of Cement Paste Using Computational Methods  

E-Print Network [OSTI]

this thesis is that the apparent viscoelastic behavior due to dissolution of load bearing phases is substantial. The dissolution process occurring during the hydration reaction can change the stress distribution inside cementitious materials, resulting...

Li, Xiaodan

2012-07-16T23:59:59.000Z

31

1-D closure models for slender 3-D viscoelastic free jets: von Karman flow geometry and elliptical cross section  

SciTech Connect (OSTI)

In this paper we derive one space dimensional, reduced systems of equations (1-D closure models) for viscoelastic free jets. We begin with the three-dimensional system of conservation laws and a Maxwell-Jeffreys constitutive law for an incompressible viscoelastic fluid. First, we exhibit exact truncations to a finite, closed system of 1-D equations based on classical velocity assumptions of von Karman. Next, we demonstrate that the 3-D free surface boundary conditions overconstrain these truncated systems, so that only a very limited class of solutions exist. We then proceed to derive approximate 1-D closure theories through a slender jet asymptotic scaling, combined with appropriate definitions of velocity, pressure and stress unknowns. Our nonaxisymmetric 1-D slender jet models incorporate the physical effects of inertia, viscoelasticity (viscosity, relaxation and retardation), gravity, surface tension, and properties of the ambient fluid, and include shear stresses and time dependence. Previous special 1-D slender jet models correspond to the lowest order equations in the present asymptotic theory by an a posteriori suppression to leading order of some of these effects, and a reduction to axisymmetry. Solutions of the lowest order system of equations in this asymptotic analysis are presented: For the special cases of elliptical inviscid and Newtonian free jets, subject to the effects of surface tension and gravity, our model predicts oscillation of the major axis of the free surface elliptical cross section between perpendicular directions with distance down the jet, and drawdown of the cross section, in agreement with observed behavior. 15 refs.

Bechtel, S.E.; Forest, M.G.; Holm, D.D.; Lin, K.J.

1988-01-01T23:59:59.000Z

32

Deformations of Geometric Structures in Topological Sigma Models  

SciTech Connect (OSTI)

We study a Lie algebra of formal vector fields W{sub n} with it application to the perturbative deformed holomorphic symplectic structure in the A-model, and a Calabi-Yau manifold with boundaries in the B-model. We show that equivalent classes of deformations are described by a Hochschild cohomology of the DG-algebra A = (A,Q), Q = {partial_derivative}-bar+{partial_derivative}{sub deform,} which is defined to be the cohomology of (-1){sup n}Q+d{sub Hoch}. Here {partial_derivative}-bar is the initial non-deformed BRST operator while {partial_derivative}{sub deform} is the deformed part whose algebra is a Lie algebra of linear vector fields gl{sub n}.

Bytsenko, A. A. [Departamento de Fisica, Universidade Estadual de Londrina, Caixa Postal 6001, Londrina-Parana (Brazil)

2010-11-25T23:59:59.000Z

33

Viscoelastic effects on frequency tuning of a dielectric elastomer membrane resonator  

SciTech Connect (OSTI)

As a recent application of dielectric elastomers (DEs), DE resonators have become an alternative to conventional silicon-based resonators used in MEMS and have attracted much interest from the research community. However, most existing modeling works for the DE resonators ignore the intrinsic viscoelastic effect of the material that may strongly influence their dynamic performance. Based on the finite-deformation viscoelasticity theory for dielectrics, this paper theoretically examines the in-plane oscillation of a DE membrane resonator to demonstrate how the material viscoelasticity affects the actuation and frequency tuning processes of the resonator. From the simulation results, it is concluded that not only the applied voltage can change the natural frequency of the resonator, but also the inelastic deformation contributes to frequency tuning. Due to the viscoelasticity of the material, the electrical loading rate influences the actuation process of the DE resonator, while it has little effect on the final steady frequency tuned by the prescribed voltage within the safety range. With the consideration of the typical failure modes of the resonator and the evolution process of the material, the tunable frequency range and the safe range of the applied voltage of the DE membrane resonator with different dimension parameters are determined in this work, which are found to be dependent on the electrical loading rate. This work is expected to provide a better understanding on the frequency tuning of viscoelastic DE membrane resonators and a guideline for the design of DE devices.

Zhou, Jianyou; Jiang, Liying, E-mail: lyjiang@eng.uwo.ca; Khayat, Roger E. [Department of Mechanical and Materials Engineering, The University of Western Ontario, London, Ontario N6A 5B9 (Canada)

2014-03-28T23:59:59.000Z

34

Relativistic Hartree-Fock-Bogoliubov model for deformed nuclei  

SciTech Connect (OSTI)

The relativistic Hartree-Fock-Bogoliubov model for axially deformed nuclei (RHFBz) is introduced. The model is based on an effective Lagrangian with density-dependent meson-nucleon couplings in the particle-hole channel, and the central part of the Gogny force is used in the pairing channel. The RHFBz quasiparticle equations are solved by expansion in the basis of a deformed harmonic oscillator. Illustrative RHFBz calculations are performed for carbon, neon, and magnesium isotopes. The effect of explicitly including the pion field is investigated for binding energies, deformation parameters, and charge radii and has an impact on the nuclei's shape.

Ebran, J.-P.; Khan, E.; Pena Arteaga, D. [Institut de Physique Nucleaire, Universite Paris-Sud, IN2P3-CNRS, FR-91406 Orsay Cedex (France); Vretenar, D. [Physics Department, Faculty of Science, University of Zagreb, HR-10000 Zagreb (Croatia)

2011-06-15T23:59:59.000Z

35

A Four-Dimensional Viscoelastic Deformation Model For Long Valley Caldera,  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating SolarElectric Coop,SaveWhiskey Flatshydro Homepowering9centuryGeneralNHawaii

36

Viscoelastic behavior of fiber-reinforced composite materials undergoing cure  

E-Print Network [OSTI]

A viscoelastic material model has been proposed to characterize the curing and thermal effects on the viscoelastic material properties of both the matrix material and the composite lamina. Micromechanics simulations are used to generate...

Wang, Kai

1999-01-01T23:59:59.000Z

37

Detection of Cardiac Occlusions Using Viscoelastic Wave Propagation  

E-Print Network [OSTI]

Detection of Cardiac Occlusions Using Viscoelastic Wave Propagation H.T. Banks and J. R. Samuels driven viscoelastic (VE) waves propagated through biotissue to body surface sensors. We in- vestigate: Inverse problems, viscoelastic models, wave propagation in biotissue, statistical models. AMS Subject

38

Viscoelastic acoustic response of layered polymer films at fluid-solid interfaces: Continuum mechanics approach  

E-Print Network [OSTI]

We have derived the general solution of a wave equation describing the dynamics of two-layere viscoelastic polymer materials of arbitrary thickness deposited on solid (quartz) surfaces in a fluid environment. Within the Voight model of viscoelastic element, we calculate the acoustic response of the system to an applied shear stress, i.e. we find the shift of the quartz generator resonance frequency and of the dissipation factor, and show that it strongly depends on the viscous loading of the adsorbed layers and on the shear storage and loss moduli of the overlayers. These results can readily be applied to quartz crystal acoustical measurements of the viscoelasticity of polymers, which conserve their shape under the shear deformations and do not flow, and layered structures such as protein films adsorbed from solution onto the surface of self-assembled monolayres.

M. V. Voinova; M. Rodahl; M. Jonson; B. Kasemo

1998-05-21T23:59:59.000Z

39

MULTISCALE MODELING OF DIFFUSION-INDUCED DEFORMATION PROCESSES  

E-Print Network [OSTI]

MULTISCALE MODELING OF DIFFUSION- INDUCED DEFORMATION PROCESSES Dr. Eugene Olevsky Friday, February 19, 2010 Engineering Bldg. Room E 300 Sintering is a high temperature process of bonding together of matter transport by different diffusion mechanisms driven by the high surface energy of aggregates

Ponce, V. Miguel

40

Structured Deformations as Energy Minimizers in Models of Fracture and  

E-Print Network [OSTI]

Structured Deformations as Energy Minimizers in Models of Fracture and Hysteresis R. Choksi and for a bar experiencing both smooth exten- sion and macroscopic fractures then are determined, and applications to the shearing of single crystals and to the cohesive fracture of solids are discussed. Yield

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Interactive Furniture Design: Using Deformable Models to Create Chairs  

E-Print Network [OSTI]

Brand, MIT Media Laboratory Abstract Deformable models that evolve under a set of mutual forces and structurally sound. We encode the input image and knowledge of furniture design into a set of force fields as input an image of the silhouette of a seated person, and then designs a chair that is comfortable

Agarwala, Aseem

42

Relativistic viscoelastic fluid mechanics  

E-Print Network [OSTI]

A detailed study is carried out for the relativistic theory of viscoelasticity which was recently constructed on the basis of Onsager's linear nonequilibrium thermodynamics. After rederiving the theory using a local argument with the entropy current, we show that this theory universally reduces to the standard relativistic Navier-Stokes fluid mechanics in the long time limit. Since effects of elasticity are taken into account, the dynamics at short time scales is modified from that given by the Navier-Stokes equations, so that acausal problems intrinsic to relativistic Navier-Stokes fluids are significantly remedied. We in particular show that the wave equations for the propagation of disturbance around a hydrostatic equilibrium in Minkowski spacetime become symmetric hyperbolic for some range of parameters, so that the model is free of acausality problems. This observation suggests that the relativistic viscoelastic model with such parameters can be regarded as a causal completion of relativistic Navier-Stokes fluid mechanics. By adjusting parameters to various values, this theory can treat a wide variety of materials including elastic materials, Maxwell materials, Kelvin-Voigt materials, and (a nonlinearly generalized version of) simplified Israel-Stewart fluids, and thus we expect the theory to be the most universal description of single-component relativistic continuum materials. We also show that the presence of strains and the corresponding change in temperature are naturally unified through the Tolman law in a generally covariant description of continuum mechanics.

Masafumi Fukuma; Yuho Sakatani

2011-09-01T23:59:59.000Z

43

Thermostatistics of ?-deformed analog of Bose gas model  

E-Print Network [OSTI]

For the recently introduced \\mu-deformed analog of Bose gas model (\\mu-Bose gas model) we study some thermodynamical aspects. Namely, we calculate total number of particles and, from it, the deformed partition function, both involving dependence on the deformation parameter \\mu. Such dependence of thermodynamic functions on the \\mu-parameter is at the core of modification of Bose gas model and arises through the use of new techniques given by us, the \\mu-calculus, an alternative to the well-known q-calculus (Jackson derivative and integral). Necessary elements of \\mu-calculus are first presented. Then, for high temperatures we obtain virial expansion of the equation of state and find five first virial coefficients, as functions of \\mu. At the other end, for low temperatures the critical temperature of condensation T_c^(\\mu) depending on \\mu is found and compared with the usual T_c, and with the T_c^(p,q) of earlier studied p,q-Bose gas model. The internal energy, specific heat and the entropy of \\mu-Bose gas are also given, both for high and low temperatures. Features peculiar for the \\mu-Bose gas model are emphasized.

A. M. Gavrilik; I. I. Kachurik; A. P. Rebesh

2013-09-05T23:59:59.000Z

44

Modeling of friction-induced deformation and microstructures.  

SciTech Connect (OSTI)

Frictional contact results in surface and subsurface damage that could influence the performance, aging, and reliability of moving mechanical assemblies. Changes in surface roughness, hardness, grain size and texture often occur during the initial run-in period, resulting in the evolution of subsurface layers with characteristic microstructural features that are different from those of the bulk. The objective of this LDRD funded research was to model friction-induced microstructures. In order to accomplish this objective, novel experimental techniques were developed to make friction measurements on single crystal surfaces along specific crystallographic surfaces. Focused ion beam techniques were used to prepare cross-sections of wear scars, and electron backscattered diffraction (EBSD) and TEM to understand the deformation, orientation changes, and recrystallization that are associated with sliding wear. The extent of subsurface deformation and the coefficient of friction were strongly dependent on the crystal orientation. These experimental observations and insights were used to develop and validate phenomenological models. A phenomenological model was developed to elucidate the relationships between deformation, microstructure formation, and friction during wear. The contact mechanics problem was described by well-known mathematical solutions for the stresses during sliding friction. Crystal plasticity theory was used to describe the evolution of dislocation content in the worn material, which in turn provided an estimate of the characteristic microstructural feature size as a function of the imposed strain. An analysis of grain boundary sliding in ultra-fine-grained material provided a mechanism for lubrication, and model predictions of the contribution of grain boundary sliding (relative to plastic deformation) to lubrication were in good qualitative agreement with experimental evidence. A nanomechanics-based approach has been developed for characterizing the mechanical response of wear surfaces. Coatings are often required to mitigate friction and wear. Amongst other factors, plastic deformation of the substrate determines the coating-substrate interface reliability. Finite element modeling has been applied to predict the plastic deformation for the specific case of diamond-like carbon (DLC) coated Ni alloy substrates.

Michael, Joseph Richard; Prasad, Somuri V.; Jungk, John Michael; Cordill, Megan J. (University of Minnesota); Bammann, Douglas J.; Battaile, Corbett Chandler; Moody, Neville Reid; Majumdar, Bhaskar Sinha (New Mexico Institure of Mining and Technology)

2006-12-01T23:59:59.000Z

45

A Mechanism-based Model for Deformation Twinning in Polycrystalline...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

in Polycrystalline FCC Steel. Abstract: Deformation twinning, a common and important plastic deformation mechanism, is the key contributor to the excellent combination of...

46

Dynamics and Stability of Rolling Viscoelastic Tires  

SciTech Connect (OSTI)

Current steady state rolling tire calculations often do not include treads because treads destroy the rotational symmetry of the tire. We describe two methodologies to compute time periodic solutions of a two-dimensional viscoelastic tire with treads: solving a minimization problem and solving a system of equations. We also expand on work by Oden and Lin on free spinning rolling elastic tires in which they disovered a hierachy of N-peak steady state standing wave solutions. In addition to discovering a two-dimensional hierarchy of standing wave solutions that includes their N-peak hiearchy, we consider the eects of viscoelasticity on the standing wave solutions. Finally, a commonplace model of viscoelasticity used in our numerical experiments led to non-physical elastic energy growth for large tire speeds. We show that a viscoelastic model of Govindjee and Reese remedies the problem.

Potter, Trevor

2013-04-30T23:59:59.000Z

47

Hereditary kernel identification method of nonlinear polymeric viscoelastic materials  

E-Print Network [OSTI]

This paper deals with a polymeric matrix composite material. The matrix behaviour is described by the modified Rabotnov's nonlinear viscoelastic model assuming the material is nonlinear viscoelastic. The parameters of creep and stress-relaxation kernels of the model are determined. From the experimental data related to kernels approximated by spline functions and by means of the method of weighted residual, the formulas for the determination of viscoelastic parameters are derived.

Olodo Emmanuel; Villevo Adanhounme; Mahouton Norbert Hounkonnou

2012-12-26T23:59:59.000Z

48

Characterization of viscoelastic properties of submarine sediments  

E-Print Network [OSTI]

simplified, it is sufficient for the intent of this discussion. From this simplified model of clay structure some of the factors affecting the viscoelastic nature of submarine clays can be identified. When the flocculent clay structure is first subjected... 1975 Major Subject: Civil Engineering CHARACTERIZATION OF VISCOELASTIC PROPERTIES OF SUBMARINE SEDIMENTS A Thesis by Jim Bob King Approved as to sty1e and content by: Chair an of Commi tee Head of Department Member Member December 1975...

King, Jim Bob

1975-01-01T23:59:59.000Z

49

Winding vacuum energies in a deformed O(4) sigma model  

E-Print Network [OSTI]

We consider the problem of calculating the Casimir energies in the winding sectors of Fateev's SS-model, which is an integrable two-parameter deformation of the O(4) non-linear sigma model in two dimensions. This problem lies beyond the scope of all traditional methods of integrable quantum field theory including the thermodynamic Bethe ansatz and non-linear integral equations. Here we propose a solution based on a remarkable correspondence between classical and quantum integrable systems and express the winding energies in terms of certain solutions of the classical sinh-Gordon equation.

Vladimir V. Bazhanov; Gleb A. Kotousov; Sergei L. Lukyanov

2014-09-01T23:59:59.000Z

50

Modeling level structures of odd-odd deformed nuclei  

SciTech Connect (OSTI)

A technique for modeling quasiparticle excitation energies and rotational parameters in odd-odd deformed nuclei has been applied to actinide species where new experimental data have been obtained by use of neutron-capture gamma-ray spectroscopy. The input parameters required for the calculation were derived from empirical data on single-particle excitations in neighboring odd-mass nuclei. Calculated configuration-specific values for the Gallagher-Moszkowski splittings were used. Calculated and experimental level structures for /sup 238/Np, /sup 244/Am, and /sup 250/Bk are compared, as well as those for several nuclei in the rare-earth region. The agreement for the actinide species is excellent, with bandhead energies deviating 22 keV and rotational parameters 5%, on the average. Corresponding average deviations for five rare-earth nuclei are 47 keV and 7%. Several applications of this modeling technique are discussed. 18 refs., 5 figs., 4 tabs.

Hoff, R.W.; Kern, J.; Piepenbring, R.; Boisson, J.P.

1984-09-07T23:59:59.000Z

51

Development and numerical implementation of nonlinear viscoelastic-viscoplastic model for asphalt materials  

E-Print Network [OSTI]

pavements is illustrated using finite element simulations. The constitutive model developed in this study can describe the behavior of asphalt materials (asphalt binder, asphalt mastic and mixtures) under various testing conditions. This study also achieved...

Huang, Chien-Wei

2009-05-15T23:59:59.000Z

52

Homogenization of a Multiscale Viscoelastic Model with Nonlocal Damping, Application to the Human Lungs  

E-Print Network [OSTI]

]. Our motiva- tion concerns the mathematical modeling of the human respiratory system and our interest an abstract convergence condition on this nonlocal operator. We derive some mechanical properties of the limit of air through the respiratory tract from its ex- ternal entries, the nose and the mouth. During

Paris-Sud XI, Université de

53

Modeling Attractor Deformation in the Rodent Head-Direction JEREMY P. GOODRIDGE1  

E-Print Network [OSTI]

Modeling Attractor Deformation in the Rodent Head-Direction System JEREMY P. GOODRIDGE1 AND DAVID S attractor deformation in the rodent head-direction system. J Neurophysiol 83: 3402­3410, 2000. We present a model of the head-direction circuit in the rat that improves on earlier models in several respects

Touretzky, David S.

54

Efficient modelling of particle collisions using a non-linear viscoelastic contact force  

E-Print Network [OSTI]

In this paper the normal collision of spherical particles is investigated. The particle interaction is modelled in a macroscopic way using the Hertzian contact force with additional linear damping. The goal of the work is to develop an efficient approximate solution of sufficient accuracy for this problem which can be used in soft-sphere collision models for Discrete Element Methods and for particle transport in viscous fluids. First, by the choice of appropriate units, the number of governing parameters of the collision process is reduced to one, thus providing a dimensionless parameter that characterizes all such collisions up to dynamic similitude. It is a simple combination of known material parameters as well as initial conditions. A rigorous calculation of the collision time and restitution coefficient from the governing equations, in the form of a series expansion in this parameter is provided. Such a first principles calculation is particularly interesting from a theoretical perspective. Since the governing equations present some technical difficulties, the methods employed are also of interest from the point of view of the analytical technique. Using further approximations, compact expressions for the restitution coefficient and the collision time are then provided. These are used to implement an approximate algebraic rule for computing the desired stiffness and damping in the framework of the adaptive collision model (Kempe & Fr\\"ohlich, J. Fluid Mech., 709: 445-489, 2012). Numerical tests with binary as well as multiple particle collisions are included that illustrate the accuracy of the proposed method and its superiority in terms of numerical efficiency.

Shouryya Ray; Tobias Kempe; Jochen Fröhlich

2015-02-26T23:59:59.000Z

55

Computational experiences with variable modulus, elastic-plastic, and viscoelastic concrete models. [HTGR  

SciTech Connect (OSTI)

Six years ago the Reactor Safety Research Division of the Nuclear Regulatory Commission (NRC) approached the Los Alamos National Laboratory to develop a comprehensive concrete structural analysis code to predict the static and dynamic behavior of Prestressed Concrete Reactor Vessels (PCRVs) that serve as the containment structure of a High-Temperature Gas-Cooled Reactor. The PCRV is a complex concrete structure that must be modeled in three dimensions and posseses other complicating features such as a steel liner for the reactor cavity and woven cables embedded vertically in the PCRV and wound circumferentially on the outside of the PCRV. The cables, or tendons, are used for prestressing the reactor vessel. In addition to developing the computational capability to predict inelastic three dimensional concrete structural behavior, the code response was verified against documented experiments on concrete structural behavior. This code development/verification effort is described.

Anderson, C.A.

1981-01-01T23:59:59.000Z

56

STATISTICAL MECHANICS MODELING OF MESOSCALE DEFORMATION IN METALS  

SciTech Connect (OSTI)

The research under this project focused on a theoretical and computational modeling of dislocation dynamics of mesoscale deformation of metal single crystals. Specifically, the work aimed to implement a continuum statistical theory of dislocations to understand strain hardening and cell structure formation under monotonic loading. These aspects of crystal deformation are manifestations of the evolution of the underlying dislocation system under mechanical loading. The project had three research tasks: 1) Investigating the statistical characteristics of dislocation systems in deformed crystals. 2) Formulating kinetic equations of dislocations and coupling these kinetics equations and crystal mechanics. 3) Computational solution of coupled crystal mechanics and dislocation kinetics. Comparison of dislocation dynamics predictions with experimental results in the area of statistical properties of dislocations and their field was also a part of the proposed effort. In the first research task, the dislocation dynamics simulation method was used to investigate the spatial, orientation, velocity, and temporal statistics of dynamical dislocation systems, and on the use of the results from this investigation to complete the kinetic description of dislocations. The second task focused on completing the formulation of a kinetic theory of dislocations that respects the discrete nature of crystallographic slip and the physics of dislocation motion and dislocation interaction in the crystal. Part of this effort also targeted the theoretical basis for establishing the connection between discrete and continuum representation of dislocations and the analysis of discrete dislocation simulation results within the continuum framework. This part of the research enables the enrichment of the kinetic description with information representing the discrete dislocation systems behavior. The third task focused on the development of physics-inspired numerical methods of solution of the coupled dislocation kinetics and crystal mechanics framework. To a large extent, this task has also been successfully started. We have developed a custom finite-element approach with mesh points being a subset of the underlying crystal structure. When used to predict the evolution of the dislocation system, the planar motion of dislocations is naturally captured for all slip systems, thus minimizing numerical errors and providing simple ways to investigate cross slip and dislocation reactions. Preliminary results in this direction show that we are closer than ever in building a predictive framework for dislocation dynamics and mesoscale plasticity based on the first principles of dislocation dynamics. The rest of the report gives and overview of the research performed under this project and highlights the key results and open questions left for future investigations.

Anter El-Azab

2013-04-08T23:59:59.000Z

57

Seismic viscoelastic attenuation Submitted to  

E-Print Network [OSTI]

Seismic viscoelastic attenuation Submitted to: Encyclopedia of Solid Earth Geophysics Harsh Gupta-3046 USA E-mail: vernon.cormier@uconn.edu Tel: 860-486-3547 Fax: 860-486-3346 #12;SEISMIC VISCOELASTIC ATTENUATION Synonyms Seismic intrinsic attenuation Definitions Linear viscoelastic attenuation. The loss

Cormier, Vernon F.

58

Kinematic models of interseismic deformation in Southern California  

E-Print Network [OSTI]

We develop a framework for interpreting geodetic measurements of interseismic deformation and geologic slip rate estimates in terms of block motions. This method accounts for the effects of block rotations and interseismic ...

Meade, Brendan J. (Brendan Joseph), 1975-

2004-01-01T23:59:59.000Z

59

WAVE SPEEDS FOR AN ELASTOPLASTIC MODEL FOR TWODIMENSIONAL DEFORMATIONS WITH A NONASSOCIATIVE FLOW RULE  

E-Print Network [OSTI]

WAVE SPEEDS FOR AN ELASTOPLASTIC MODEL FOR TWO­DIMENSIONAL DEFORMATIONS WITH A NON­ASSOCIATIVE FLOW of variables, the character­ istic speeds of plane wave solutions of the system are computed. For both plastic and elastic deformations, there are two nonzero wave speeds, referred to as fast and slow waves. It is shown

60

Deformable model for 3D intramodal nonrigid breast image registration with fiducial skin markers  

E-Print Network [OSTI]

of FSM, finite element method (FEM) is used to distribute the markers' displacements linearly over with rigid registration technique. Keywords: Intramodal image registration, finite element method, deformable, we developed a finite element method (FEM) deformable breast model to correct motion artifacts

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61

Thermodynamics of viscoelastic fluids: the temperature equation.  

E-Print Network [OSTI]

Thermodynamics of viscoelastic fluids: the temperature equation. Peter Wapperom Martien A. Hulsen and Hydrodynamics Rotterdamseweg 145 2628 AL Delft (The Netherlands) Abstract From the thermodynamics with internal. The well- known stress differential models that fit into the thermodynamic theory will be treated

Wapperom, Peter

62

(Non)renormalizability of the D-deformed Wess-Zumino model  

SciTech Connect (OSTI)

We continue the analysis of the D-deformed Wess-Zumino model that we introduced in M. Dmitrijevic and V. Radovanovic, J. High Energy Phys. 04 (2009) 108. The model is defined by a deformation that is non-Hermitian and given in terms of the covariant derivatives D{sub {alpha}.} We calculate one-loop divergences in the two-point, three-point, and four-point Green functions. Possibilities to render the model renormalizable are discussed.

Dimitrijevic, Marija [INFN Gruppo collegato di Alessandria, Via Bellini 25/G, 15100 Alessandria (Italy); University of Belgrade, Faculty of Physics Studentski trg 12, 11000 Beograd (Serbia); Nikolic, Biljana; Radovanovic, Voja [University of Belgrade, Faculty of Physics Studentski trg 12, 11000 Beograd (Serbia)

2010-05-15T23:59:59.000Z

63

Computational implementation of the multi-mechanism deformation coupled fracture model for salt  

SciTech Connect (OSTI)

The Multi-Mechanism Deformation (M-D) model for creep in rock salt has been used in three-dimensional computations for the Waste Isolation Pilot Plant (WIPP), a potential waste, repository. These computational studies are relied upon to make key predictions about long-term behavior of the repository. Recently, the M-D model was extended to include creep-induced damage. The extended model, the Multi-Mechanism Deformation Coupled Fracture (MDCF) model, is considerably more complicated than the M-D model and required a different technology from that of the M-D model for a computational implementation.

Koteras, J.R.; Munson, D.E.

1996-05-01T23:59:59.000Z

64

Vane shear determination of the visco-elastic shear modulus of submarine sediments  

E-Print Network [OSTI]

the process of deformation under shear can be considered and some of the factors affecting the viscoelastic nature of submarine clays can be identified. When the flocculent clay structure is subjected to shear the bonds between the particles ai e first... of MASTER OF SCIENCE December 1973 Major Subject: Civil Engineering VANE SHEAR DETERMINATION OF THE VISCOELASTIC SHEAR MODULUS OF SUBMARINE SEDIMENTS A Thesis by Herbert Scott Stevenson Approved as to style and content by: Chairman of Committ e M...

Stevenson, Herbert Scott

1973-01-01T23:59:59.000Z

65

Modeling for deformable mirrors and the adaptive optics optimization program  

SciTech Connect (OSTI)

We discuss aspects of adaptive optics optimization for large fusion laser systems such as the 192-arm National Ignition Facility (NIF) at LLNL. By way of example, we considered the discrete actuator deformable mirror and Hartmann sensor system used on the Beamlet laser. Beamlet is a single-aperture prototype of the 11-0-5 slab amplifier design for NIF, and so we expect similar optical distortion levels and deformable mirror correction requirements. We are now in the process of developing a numerically efficient object oriented C++ language implementation of our adaptive optics and wavefront sensor code, but this code is not yet operational. Results are based instead on the prototype algorithms, coded-up in an interpreted array processing computer language.

Henesian, M.A.; Haney, S.W.; Trenholme, J.B. [Lawrence Livermore National Lab., CA (United States); Thomas, M. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center

1997-03-18T23:59:59.000Z

66

Discrete element modeling of rock deformation, fracture network development and permeability evolution under hydraulic stimulation  

SciTech Connect (OSTI)

Key challenges associated with the EGS reservoir development include the ability to reliably predict hydraulic fracturing and the deformation of natural fractures as well as estimating permeability evolution of the fracture network with time. We have developed a physics-based rock deformation and fracture propagation simulator by coupling a discrete element model (DEM) for fracturing with a network flow model. In DEM model, solid rock is represented by a network of discrete elements (often referred as particles) connected by various types of mechanical bonds such as springs, elastic beams or bonds that have more complex properties (such as stress-dependent elastic constants). Fracturing is represented explicitly as broken bonds (microcracks), which form and coalesce into macroscopic fractures when external and internal load is applied. The natural fractures are represented by a series of connected line segments. Mechanical bonds that intersect with such line segments are removed from the DEM model. A network flow model using conjugate lattice to the DEM network is developed and coupled with the DEM. The fluid pressure gradient exerts forces on individual elements of the DEM network, which therefore deforms the mechanical bonds and breaks them if the deformation reaches a prescribed threshold value. Such deformation/fracturing in turn changes the permeability of the flow network, which again changes the evolution of fluid pressure, intimately coupling the two processes. The intimate coupling between fracturing/deformation of fracture networks and fluid flow makes the meso-scale DEM- network flow simulations necessary in order to accurately evaluate the permeability evolution, as these methods have substantial advantages over conventional continuum mechanical models of elastic rock deformation. The challenges that must be overcome to simulate EGS reservoir stimulation, preliminary results, progress to date and near future research directions and opportunities will be discussed. Methodology for coupling the DEM model with continuum flow and heat transport models will also be discussed.

Shouchun Deng; Robert Podgorney; Hai Huang

2011-02-01T23:59:59.000Z

67

Semiclassical origin of anomalous shell effect for tetrahedral deformation in radial power-law potential model  

E-Print Network [OSTI]

Shell structures in single-particle energy spectra are investigated against regular tetrahedral type deformation using radial power-law potential model. Employing a natural way of shape parametrization which interpolates sphere and regular tetrahedron, we find prominent shell effects at rather large tetrahedral deformations, which bring about shell energies much larger than the cases of spherical and quadrupole type shapes. We discuss the semiclassical origin of these anomalous shell structures using periodic orbit theory.

Ken-ichiro Arita; Yasunori Mukumoto

2014-05-09T23:59:59.000Z

68

Analysis of viscoelastic soft dielectric elastomer generators operating in an electrical circuit  

E-Print Network [OSTI]

A predicting model for soft Dielectric Elastomer Generators (DEGs) must consider a realistic model of the electromechanical behaviour of the elastomer filling, the variable capacitor and of the electrical circuit connecting all elements of the device. In this paper such an objective is achieved by proposing a complete framework for reliable simulations of soft energy harvesters. In particular, a simple electrical circuit is realised by connecting the capacitor, stretched periodically by a source of mechanical work, in parallel with a battery through a diode and with an electrical load consuming the energy produced. The electrical model comprises resistances simulating the effect of the electrodes and of the conductivity current invariably present through the dielectric film. As these devices undergo a high number of electro-mechanical loading cycles at large deformation, the time-dependent response of the material must be taken into account as it strongly affects the generator outcome. To this end, the viscoelastic behaviour of the polymer and the possible change of permittivity with strains are analysed carefully by means of a proposed coupled electro-viscoelastic constitutive model, calibrated on experimental data available in the literature for an incompressible polyacrilate elastomer (3M VHB4910). Numerical results showing the importance of time-dependent behaviour on the evaluation of performance of DEGs for different loading conditions, namely equi-biaxial and uniaxial, are reported in the final section.

Eliana Bortot; Ralf Denzer; Andreas Menzel; Massimiliano Gei

2014-11-13T23:59:59.000Z

69

MetaMorphs: Deformable Shape and Texture Models Xiaolei Huang, Dimitris Metaxas, Ting Chen  

E-Print Network [OSTI]

dimensional space of distance transforms. The interior texture is captured using a nonparametric kernel-based approximation of the inten- sity probability density function (p.d.f.) inside the model. The deformations. We demonstrate the power of our new models to segmentation applications, and vari- ous examples

70

Numerical Model for the Deformation of Nucleated Cells by Optical Stretchers  

E-Print Network [OSTI]

In this paper, we seek to model the deformation of nucleated cells by single diode-laser bar optical stretchers. We employ a recently developed computational model, the Dynamic Ray-Tracing method, to determine the stress distribution induced by the applied optical forces on a capsule encapsulating a nucleus of different optical properties. These forces are shape dependent and can deform real non-rigid objects; thus resulting in a dynamically changing optical stress distribution with cell and nucleus deformation. Chinese hamster ovary cell is a common biological cell that is of interest to the biomedical community because of their use in recombinant protein therapeutics and is an example of a nucleated cell. To this end, we model chinese hamster ovary cells as two three-dimensional elastic capsules of variable inner capsule size immersed in a fluid where the hydrodynamic forces are calculated using the Immersed Boundary Method. Our results show that the presence of a nucleus has a major effect on the force distribution on the cell surface and the net deformation. Scattering and gradient forces are reported for different nucleus sizes and the effect of nucleus size on the cell deformation is discussed.

Ihab Sraj; Joshua Francois; David W. M. Marr; Charles D. Eggleton

2015-01-15T23:59:59.000Z

71

Pumping viscoelastic two-fluid media  

E-Print Network [OSTI]

Using a two-fluid model for viscoelastic polymer solutions, we study analytically fluid transport driven by a transverse, small amplitude traveling wave propagation. The pumping flow far from the waving boundary is shown to be strongly wave number and viscosity dependent, in contrast to a viscous Newtonian fluid. We find the two qualitatively different regimes: In one regime relevant to small wave numbers, the fluidic transport is almost the same as the Newtonian case, and uniform viscoelastic constitutive equations provide a good approximation. In the other regime, the pumping is substantially decreased because of the gel-like character. The boundary separating these two regimes is clarified. Our results suggest possible needs of two-fluid descriptions for the transport and locomotion in biological fluids with cilia and flagella.

Hirofumi Wada

2010-04-08T23:59:59.000Z

72

A Lattice Boltzmann Fictitious Domain Method for Modeling Red Blood Cell Deformation and Multiple-Cell Hydrodynamic Interactions in Flow  

SciTech Connect (OSTI)

To model red blood cell (RBC) deformation in flow, the recently developed LBM-DLM/FD method ([Shi and Lim, 2007)29], derived from the lattice Boltzmann method and the distributed Lagrange multiplier/fictitious domain methodthe fictitious domain method, is extended to employ the mesoscopic network model for simulations of red blood cell deformation. The flow is simulated by the lattice Boltzmann method with an external force, while the network model is used for modeling red blood cell deformation and the fluid-RBC interaction is enforced by the Lagrange multiplier. To validate parameters of the RBC network model, sThe stretching numerical tests on both coarse and fine meshes are performed and compared with the corresponding experimental data to validate the parameters of the RBC network model. In addition, RBC deformation in pipe flow and in shear flow is simulated, revealing the capacity of the current method for modeling RBC deformation in various flows.

Shi, Xing; Lin, Guang; Zou, Jianfeng; Fedosov, Dmitry A.

2013-07-20T23:59:59.000Z

73

Modeling the electrical resistivity of deformation processed metal-metal composites  

SciTech Connect (OSTI)

Deformation processed metal–metal (matrix–reinforcement) composites (DMMCs) are high-strength, high-conductivity in situ composites produced by severe plastic deformation. The electrical resistivity of DMMCs is rarely investigated mechanistically and tends to be slightly higher than the rule-of-mixtures prediction. In this paper, we analyze several possible physical mechanisms (i.e. phonons, interfaces, mutual solution, grain boundaries, dislocations) responsible for the electrical resistivity of DMMC systems and how these mechanisms could be affected by processing conditions (i.e. temperature, deformation processing). As an innovation, we identified and assembled the major scattering mechanisms for specific DMMC systems and modeled their electrical resistivity in combination. From this analysis, it appears that filament coarsening rather than dislocation annihilation is primarily responsible for the resistivity drop observed in these materials after annealing and that grain boundary scattering contributes to the resistivity at least at the same magnitude as does interface scattering.

Tian, Liang [Ames Laboratory; Anderson, Iver [Ames Laboratory; Riedemann, Trevor [Ames Laboratory; Russell, Alan [Ames Laboratory

2014-09-01T23:59:59.000Z

74

Training PDMs on models: The Case of Deformable Superellipses  

E-Print Network [OSTI]

- plicated mathematical shape model simpler while keeping a comparable level of representational power? The proposed solution is to use the original model itself { which represents a class of shapes { to train Introduction Superellipses and their 3-D extension superquadrics were introduced by the Danish designer Piet

Fisher, Bob

75

Deformations of Quantum Field Theories and the Construction of Interacting Models  

E-Print Network [OSTI]

The subject of this thesis is the rigorous construction of QFT models with nontrivial interaction. Two different approaches in the framework of AQFT are discussed. On the one hand, an inverse scattering problem is considered. A given factorizing S-matrix is thereby taken as the starting point of the construction. The particle spectrum taken into account involves an arbitrary number of massive particle species, transforming under a global gauge group. Starting from known wedge-local auxiliary fields, the transition to local theories is shown. To his end, we make use of the modular nuclearity condition and investigate certain maps from the wedge algebras, generated by the auxiliary fields, to the considered Hilbert space. Under a very plausible conjecture it is shown that these maps are nuclear, which implies the nontriviality of algebras associated with bounded regions in the sense that the Reeh-Schlieder property holds. A large class of integrable models with factorizing S-matrices in 1+1 dimensions can be constructed in this way. Among them are the O(N)-invariant nonlinear sigma-models. Deformation techniques, on the other hand, constitute a method of construction which may be applied in arbitrary spacetime dimensions. This approach starts from a known quantum field theoretic model which is subjected to a certain modification. Here, concretely, the model of a scalar massive Fermion was deformed. The emerging models are based on wedge-local fields, allowing for the computation of the two-particle S-matrix. The resulting scattering matrix depends on the deformation and differs from the one of the initial model. By restricting to 1+1 dimensions, the deformation method yields a large class of integrable models with factorizing S-matrices, including the Sinh-Gordon model.

Sabina Alazzawi

2015-03-03T23:59:59.000Z

76

HERMES: A Model to Describe Deformation, Burning, Explosion, and Detonation  

SciTech Connect (OSTI)

HERMES (High Explosive Response to MEchanical Stimulus) was developed to fill the need for a model to describe an explosive response of the type described as BVR (Burn to Violent Response) or HEVR (High Explosive Violent Response). Characteristically this response leaves a substantial amount of explosive unconsumed, the time to reaction is long, and the peak pressure developed is low. In contrast, detonations characteristically consume all explosive present, the time to reaction is short, and peak pressures are high. However, most of the previous models to describe explosive response were models for detonation. The earliest models to describe the response of explosives to mechanical stimulus in computer simulations were applied to intentional detonation (performance) of nearly ideal explosives. In this case, an ideal explosive is one with a vanishingly small reaction zone. A detonation is supersonic with respect to the undetonated explosive (reactant). The reactant cannot respond to the pressure of the detonation before the detonation front arrives, so the precise compressibility of the reactant does not matter. Further, the mesh sizes that were practical for the computer resources then available were large with respect to the reaction zone. As a result, methods then used to model detonations, known as {beta}-burn or program burn, were not intended to resolve the structure of the reaction zone. Instead, these methods spread the detonation front over a few finite-difference zones, in the same spirit that artificial viscosity is used to spread the shock front in inert materials over a few finite-difference zones. These methods are still widely used when the structure of the reaction zone and the build-up to detonation are unimportant. Later detonation models resolved the reaction zone. These models were applied both to performance, particularly as it is affected by the size of the charge, and to situations in which the stimulus was less than that needed for reliable performance, whether as a result of accident, hazard, or a fault in the detonation train. These models describe the build-up of detonation from a shock stimulus. They are generally consistent with the mesoscale picture of ignition at many small defects in the plane of the shock front and the growth of the resulting hot-spots, leading to detonation in heterogeneous explosives such as plastic-bonded explosives (PBX). The models included terms for ignition, and also for the growth of reaction as tracked by the local mass fraction of product gas, {lambda}. The growth of reaction in such models incorporates a form factor that describes the change of surface area per unit volume (specific surface area) as the reaction progresses. For unimolecular crystalline-based explosives, the form factor is consistent with the mesoscale picture of a galaxy of hot spots burning outward and eventually interacting with each other. For composite explosives and propellants, where the fuel and oxidizer are segregated, the diffusion flame at the fuel-oxidizer interface can be interpreted with a different form factor that corresponds to grains burning inward from their surfaces. The form factor influences the energy release rate, and the amount of energy released in the reaction zone. Since the 19th century, gun and cannon propellants have used perforated geometric shapes that produce an increasing surface area as the propellant burns. This helps maintain the pressure as burning continues while the projectile travels down the barrel, which thereby increases the volume of the hot gas. Interior ballistics calculations use a geometric form factor to describe the changing surface area precisely. As a result, with a suitably modified form factor, detonation models can represent burning and explosion in damaged and broken reactant. The disadvantage of such models in application to accidents is that the ignition term does not distinguish between a value of pressure that results from a shock, and the same pressure that results from a more gradual increase. This disagrees with experiments, where

Reaugh, J E

2011-11-22T23:59:59.000Z

77

Using Active Deformable Models in Robotic Visual Servoing  

E-Print Network [OSTI]

of Minnesota 4-192 EE/CS Building 200 Union Street SE Minneapolis, MN 55455 September 9, 1997 Submitted to the book \\Event-Based Sensing, Planning and Control of a Robotic System: An Integrated Approach" #12 are updated at frame rates by minimizing an energy function involving the relative position of model points

78

Using Nanotechnology in Viscoelastic Surfactant Stimulation Fluids  

E-Print Network [OSTI]

Viscoelastic surfactant (VES) fluids are preferred for many applications in the oil industry. Their viscoelastic behavior is due to the overlap and entanglement of very long wormlike micelles. The growth of these wormlike micelles depends...

Gurluk, Merve Rabia 1986-

2012-11-12T23:59:59.000Z

79

Elastocapillary deformations on partially-wetting substrates: rival contact-line models  

E-Print Network [OSTI]

A partially-wetting liquid can deform the underlying elastic substrate upon which it rests. This situation requires the development of theoretical models to describe the wetting forces imparted by the drop onto the solid substrate, particularly those at the contact-line. We construct a general solution using a displacement potential function for the elastic deformations within a finite elastic substrate associated with these wetting forces, and compare the results for several different contact-line models. Our work incorporates internal contributions to the surface stress from both liquid/solid $\\Sigma_{ls}$ and solid/gas $\\Sigma_{sg}$ solid surface tensions (surface stress), which results in a non-standard boundary-value problem that we solve using a dual integral equation. We compare our results to relevant experiments and conclude that the generalization of solid surface tension $\\Sigma_{ls} \

Joshua B. Bostwick; Michael Shearer; Karen E. Daniels

2014-05-01T23:59:59.000Z

80

Numerical Model for the Deformation of Nucleated Cells by Optical Stretchers  

E-Print Network [OSTI]

In this paper, we seek to model the deformation of nucleated cells by single diode-laser bar optical stretchers. We employ a recently developed computational model, the Dynamic Ray-Tracing method, to determine the stress distribution induced by the applied optical forces on a capsule encapsulating a nucleus of different optical properties. These forces are shape dependent and can deform real non-rigid objects; thus resulting in a dynamically changing optical stress distribution with cell and nucleus deformation. Chinese hamster ovary cell is a common biological cell that is of interest to the biomedical community because of their use in recombinant protein therapeutics and is an example of a nucleated cell. To this end, we model chinese hamster ovary cells as two three-dimensional elastic capsules of variable inner capsule size immersed in a fluid where the hydrodynamic forces are calculated using the Immersed Boundary Method. Our results show that the presence of a nucleus has a major effect on the force dis...

Sraj, Ihab; Marr, David W M; Eggleton, Charles D

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Viscoelastic Model for Lung Parenchyma for Multi-Scale Modeling of Respiratory System Phase I: Hypo-Elastic Model for CFD Implementation  

SciTech Connect (OSTI)

An isotropic constitutive model for the parenchyma of lung has been derived from the theory of hypo-elasticity. The intent is to use it to represent the mechanical response of this soft tissue in sophisticated, computational, fluid-dynamic models of the lung. This demands that the continuum model be accurate, yet simple and effcient. An objective algorithm for its numeric integration is provided. The response of the model is determined for several boundary-value problems whose experiments are used for material characterization. The effective elastic, bulk, and shear moduli, and Poisson’s ratio, as tangent functions, are also derived. The model is characterized against published experimental data for lung. A bridge between this continuum model and a dodecahedral model of alveolar geometry is investigated, with preliminary findings being reported.

Freed, Alan D.; Einstein, Daniel R.

2011-04-14T23:59:59.000Z

82

Experimental characterization and crystal plasticity modeling of heterogeneous deformation in polycrystalline -Ti  

SciTech Connect (OSTI)

Grain-level heterogeneous deformation was studied in a polycrystalline {alpha}-Ti specimen deformed by four-point bending. Dislocation slip activity in the microstructure was investigated by surface slip trace analysis. Three-dimensional-X-ray diffraction (3D-XRD) was used to investigate subsurface lattice rotations and to identify geometrically necessary dislocations (GNDs). The slip systems of local GNDs were analyzed by studying the streaking directions of reflections in corresponding Laue patterns. The analysis performed in one grain indicated that the subsurface GNDs were from the same slip system identified using slip trace analysis in backscattered electron images. A crystal plasticity finite element (CPFE) model was used to simulate deformation of the same microstructural region. The predictions of dislocation slip activity match the general aspects of the experimental observations, including the ability to simulate the activation of different slip systems in grains where multiple slip systems were activated. Prediction of local crystal rotations, however, was the least accurate aspect of the CPFE model.

Wang, Leyun [Michigan State University, East Lansing; Barabash, Rozaliya [ORNL; Yang, Y [Michigan State University, East Lansing; Bieler, Prof T R [Michigan State University, East Lansing; Crimp, Prof M A [Michigan State University, East Lansing; Eisenlohr, P [Max-Planck-Institut fur Eisenforschung, Germany; Liu, W. [Argonne National Laboratory (ANL); Ice, Gene E [ORNL

2011-01-01T23:59:59.000Z

83

Deformed Matrix Models, Supersymmetric Lattice Twists and N=1/4 Supersymmetry  

SciTech Connect (OSTI)

A manifestly supersymmetric nonperturbative matrix regularization for a twisted version of N = (8, 8) theory on a curved background (a two-sphere) is constructed. Both continuum and the matrix regularization respect four exact scalar supersymmetries under a twisted version of the supersymmetry algebra. We then discuss a succinct Q = 1 deformed matrix model regularization of N = 4 SYM in d = 4, which is equivalent to a non-commutative A*{sub 4} orbifold lattice formulation. Motivated by recent progress in supersymmetric lattices, we also propose a N = 1/4 supersymmetry preserving deformation of N = 4 SYM theory on R{sup 4}. In this class of N = 1/4 theories, both the regularized and continuum theory respect the same set of (scalar) supersymmetry. By using the equivalence of the deformed matrix models with the lattice formulations, we give a very simple physical argument on why the exact lattice supersymmetry must be a subset of scalar subalgebra. This argument disagrees with the recent claims of the link approach, for which we give a new interpretation.

Unsal, Mithat

2008-09-24T23:59:59.000Z

84

Deformation Analysis of Sand Specimens using 3D Digital Image Correlation for the Calibration of an Elasto-Plastic Model  

E-Print Network [OSTI]

of the kinematic and volumetric conditions of the specimen at different stages of deformation, combined with the readings of the global axial compression of the specimen. This allowed for the characterization of a Mohr-Coulomb plasticity model with hardening...

Song, Ahran

2012-10-19T23:59:59.000Z

85

Initial-Value and Modal Approaches for Transient Viscoelastic Responses  

E-Print Network [OSTI]

) and Peltier (1974) because of the availability of more precise uplift data with more extensive geographical principle and use of the viscoelastic normal-mode approach (e.g., Peltier 1974; Yuen & Peltier 1982 in the presence of complicated stratified earth models (Han & Wahr 1995; Fang & Hager 1994, 1995; Peltier 1995

Hanyk, Ladislav

86

InitialValue and Modal Approaches for Transient Viscoelastic Responses  

E-Print Network [OSTI]

) and Peltier (1974) because of the availability of more precise uplift data with more extensive geographical principle and use of the viscoelastic normal­mode approach (e.g., Peltier 1974; Yuen & Peltier 1982 in the presence of complicated stratified earth models (Han & Wahr 1995; Fang & Hager 1994, 1995; Peltier 1995

Hanyk, Ladislav

87

Technical Note Viscoelastic Behavior of Silica Particle Compacts  

E-Print Network [OSTI]

to the noise emitted by trains, particularly high-speed trains. How soil is affected by dynamic mechanical Lu1 and D. D. L. Chung2 Abstract: The viscoelastic behavior of model sandy soils in the form is recommended for mechanical energy dissipation. DOI: 10.1061/(ASCE)MT.1943-5533.0000831. © 2014 American

Chung, Deborah D.L.

88

Development of a Two-Phase Model for the Hot Deformation of Highly-Alloyed Aluminum  

SciTech Connect (OSTI)

Conventional processing methods for highly alloyed aluminum consist of ingot casting, followed by hot rolling and thermal treatments. Defects result in lost productivity and wasted energy through the need to remelt and reprocess the material. This research centers on developing a fundamental understanding for deformation of wrought 705X series alloys, a key alloy system used in structural airframe applications. The development of damage at grain boundaries is characterized through a novel test that provides initiation of failure while preserving a controlled deformation response. Data from these mechanical tests are linked to computer simulations of the hot rolling process through a critical measure of damage. Transmission electron microscopy provides fundamental insight into deformation at these high working temperatures, and--in a novel link between microscale and macroscale response--the evolution of microstructure (crystallographic orientation) provides feedback for tuning of friction in the hot rolling process. The key product of this research is a modeling framework for the analysis of industrial hot rolling.

A. J. Beaudoin; J. A. Dantzig; I. M. Robertson; B. E. Gore; S. F. Harnish; H. A. Padilla

2005-10-31T23:59:59.000Z

89

THERMOMECHANICS OF PV MODULES INCLUDING THE VISCOELASTICITY OF EVA Ulrich Eitner1,  

E-Print Network [OSTI]

]. It is therefore essential to understand the thermomechanics, i.e. the build-up of stresses from thermal] at the Fraunhofer CSP to inspect copper ribbons in PV modules. In 2010, we presented a viscoelastic material model

90

Multi-scale Modeling Approach to Acoustic Emission during Plastic Deformation  

E-Print Network [OSTI]

We address the long standing problem of the origin of acoustic emission commonly observed during plastic deformation. We propose a frame-work to deal with the widely separated time scales of collective dislocation dynamics and elastic degrees of freedom to explain the nature of acoustic emission observed during the Portevin-Le Chatelier effect. The Ananthakrishna model is used as it explains most generic features of the phenomenon. Our results show that while acoustic emission bursts correlated with stress drops are well separated for the type C serrations, these bursts merge to form nearly continuous acoustic signals with overriding bursts for the propagating type A bands.

Jagadish Kumar; G. Ananthakrishna

2011-02-20T23:59:59.000Z

91

Mode-I fracture in a nonlinear lattice with viscoelastic forces Shay I. Heizler and David A. Kessler  

E-Print Network [OSTI]

Mode-I fracture in a nonlinear lattice with viscoelastic forces Shay I. Heizler and David A July 2002 We study mode-I fracture in a viscoelastic lattice model with a nonlinear force law force laws in mode-III fracture. At small driving, there is a strong dependency of the velocity curve

Levine, Herbert

92

Metastable vacuum decay and $?$ dependence in gauge theory. Deformed QCD as a toy model  

E-Print Network [OSTI]

We study a number of different ingredients related to the $\\theta$ dependence, metastable excited vacuum states and other related subjects using a simplified version of QCD, the so-called "deformed QCD". This model is a weakly coupled gauge theory, which however preserves all the relevant essential elements allowing us to study hard and nontrivial features which are known to be present in real strongly coupled QCD. Our main focus in this work is to test the ideas related to the metastable vacuum states (which are known to be present in strongly coupled QCD in large $N$ limit) in a theoretically controllable manner using the "deformed QCD" as a toy model. We explicitly show how the metastable states emerge in the system, why their life time is large, and why these metastable states must be present in the system for the self-consistency of the entire picture of the QCD vacuum. We also speculate on possible relevance of the metastable vacuum states in explanation of the violation of local $\\cal{P}$ and $\\cal{CP}$ symmetries in heavy ion collisions.

Amit Bhoonah; Evan Thomas; Ariel R. Zhitnitsky

2014-07-18T23:59:59.000Z

93

Finite Element Modeling of the Deformation of a Thin Magnetoelastic Film Compared to a Membrane Model  

SciTech Connect (OSTI)

Recently a new class of biocompatible elastic polymers loaded with small ferrous particles (magnetoelastomer) was developed at Lawrence Livermore National Laboratory. This new material was formed as a thin film using spin casting. The deformation of this material using a magnetic field has many possible applications to microfluidics. Two methods will be used to calculate the deformation of a circular magneto-elastomeric film subjected to a magnetic field. The first method is an arbitrary Lagrangian-Eulerian (ALE) finite element method (FEM) and the second is based on nonlinear continuum electromagnetism and continuum elasticity in the membrane limit. The comparison of these two methods is used to test/validate the finite element method.

Barham, M; White, D; Steigmann, D; Rudd, R

2009-04-08T23:59:59.000Z

94

Modeling reactive transport in deformable porous media using the theory of interacting continua.  

SciTech Connect (OSTI)

This report gives an overview of the work done as part of an Early Career LDRD aimed at modeling flow induced damage of materials involving chemical reactions, deformation of the porous matrix, and complex flow phenomena. The numerical formulation is motivated by a mixture theory or theory of interacting continua type approach to coupling the behavior of the fluid and the porous matrix. Results for the proposed method are presented for several engineering problems of interest including carbon dioxide sequestration, hydraulic fracturing, and energetic materials applications. This work is intended to create a general framework for flow induced damage that can be further developed in each of the particular areas addressed below. The results show both convincing proof of the methodologies potential and the need for further validation of the models developed.

Turner, Daniel Zack

2012-01-01T23:59:59.000Z

95

Non-Steady wall-bounded flows of viscoelastic fluids under periodic forcing  

E-Print Network [OSTI]

The problem of oscillating flows inside pipes under periodic forcing of viscoelastic fluids is addressed here. Starting from the linear Oldroyd-B model, a generalized Darcy's law is obtained in frequency domain and an explicit expression for the dependence of the dynamic permeability on fluid parameters and forcing frequency is derived. Previous results in both viscoelastic and Newtonian fluids are here shown to be particular cases of our results. On the basis of our calculations, a possible explanation for the observed damping of local dynamic response as the forcing frequency increases is given. Good fitting with recent experimental studies of wave propagation in viscoelastic media is here exhibited. Sound wave propagation in viscoelastic media flowing inside straight pipes is investigated. In particular, we obtain the local dynamic response for weakly compressible flows.

Anier Hernández-García; Antonio Fernández-Barbero; Oscar Sotolongo-Costa

2013-01-18T23:59:59.000Z

96

Coupled heat conduction and deformation in a viscoelastic composite cylinder  

E-Print Network [OSTI]

conditions, Finite Element(FE) analysis of the composite cylinder is performed and the results of analytical and FE method are found to be in good agreement. Parametric studies are carried out to understand the effect of change in material parameters namely...

Shah, Sneha

2010-01-16T23:59:59.000Z

97

3D segmentation of mouse organs from MR images using deformable simplex mesh models G. Hamarneh1  

E-Print Network [OSTI]

3D segmentation of mouse organs from MR images using deformable simplex mesh models G. Hamarneh1 , H. Delingette2 , M. Henkelman1 1 Hospital for Sick Children, Toronto, ON, Canada, 2 INRIA brains and kidneys from MR images. Algorithmic details and 3D segmentation results are presented

Hamarneh, Ghassan

98

On the intersection of the shell, collective and cluster models of atomic nuclei II: Symmetry-breaking and large deformations  

E-Print Network [OSTI]

We discuss the role of the broken symmetries in the connection of the shell, collective and cluster models. The cluster-shell competition is described in terms of cold quantum phases. Stable quasi-dynamical U(3) symmetry is found for specific large deformations for a Nilsson-type Hamiltonian.

J. Cseh; J. Darai

2014-04-14T23:59:59.000Z

99

Multiscale modeling of ice deformation behavior M. Montagnata,, O. Castelnaub, P. D. Bonsc, S. H. Fariad,e, O.  

E-Print Network [OSTI]

Multiscale modeling of ice deformation behavior M. Montagnata,, O. Castelnaub, P. D. Bonsc, S. H France (IUF), Paris, France Abstract Understanding the flow of ice in glaciers and polar ice sheets is of increasing relevance in a time of potentially significant climate change. The flow of ice has hitherto

Boyer, Edmond

100

Viscoelastic characterization of collagen-GAG scaffolds  

E-Print Network [OSTI]

An experimental study was performed to determine whether or not collagen-GAG scaffolds exhibit linear viscoelastic behavior. Tension tests were performed on dry and hydrated engineered collagen-GAG scaffolds in order to ...

Wong, Matthew Q

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Viscoelastic properties of bidisperse homopolymer blends  

E-Print Network [OSTI]

VISCOELASTIC PROPERTIES OF BIDISPKRSE HOMOPOLYMER BLENDS A Thesis by JULIANI Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December 2000... Major Subject. Chemical Engineering VISCOELASTIC PROPERTIES OF BIDISPERSE HOMOPOLYMER BLENDS A Thesis by JULIANI Submitted to Texas A&M University m partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved as to style...

Juliani

2000-01-01T23:59:59.000Z

102

A dislocation-based, strain–gradient–plasticity strengthening model for deformation processed metal–metal composites  

SciTech Connect (OSTI)

Deformation processed metal–metal composites (DMMCs) are high-strength, high-electrical conductivity composites developed by severe plastic deformation of two ductile metal phases. The extraordinarily high strength of DMMCs is underestimated using the rule of mixture (or volumetric weighted average) of conventionally work-hardened metals. In this article, a dislocation-density-based, strain–gradient–plasticity model is proposed to relate the strain-gradient effect with the geometrically necessary dislocations emanating from the interface to better predict the strength of DMMCs. The model prediction was compared with the experimental findings of Cu–Nb, Cu–Ta, and Al–Ti DMMC systems to verify the applicability of the new model. The results show that this model predicts the strength of DMMCs better than the rule-of-mixture model. The strain-gradient effect, responsible for the exceptionally high strength of heavily cold worked DMMCs, is dominant at large deformation strain since its characteristic microstructure length is comparable with the intrinsic material length.

Tian, Liang [Ames Laboratory; Russell, Alan [Ames Laboratory; Anderson, Iver [Ames Laboratory

2014-01-03T23:59:59.000Z

103

Nonlinear Shear Wave in a Non Newtonian Visco-elastic Medium  

E-Print Network [OSTI]

An analysis of nonlinear transverse shear wave has been carried out on non-Newtonian viscoelastic liquid using generalized hydrodynamic(GH) model. The nonlinear viscoelastic behavior is introduced through velocity shear dependence of viscosity coefficient by well known Carreau -Bird model. The dynamical feature of this shear wave leads to the celebrated Fermi-Pasta-Ulam (FPU) problem. Numerical solution has been obtained which shows that initial periodic solutions reoccur after passing through several patterns of periodic waves. A possible explanation for this periodic solution is given by constructing modified Korteweg de Vries (mKdV) equation. This model has application from laboratory to astrophysical plasmas as well as biological systems.

Janaki, D Banerjee M S; Chaudhuri, M

2013-01-01T23:59:59.000Z

104

Plastic deformation of a model glass induced by a local shear transformation  

E-Print Network [OSTI]

The effect of a local shear transformation on plastic deformation of a three-dimensional amorphous solid is studied using molecular dynamics simulations. We consider a spherical inclusion, which is gradually transformed into an ellipsoid of the same volume and then converted back into the sphere. It is shown that at sufficiently large strain amplitudes, the deformation of the material involves localized plastic events that were identified based on the relative displacement of atoms before and after the shear transformation. We found that the density profiles of cage jumps decay away from the inclusion, which correlates well with the radial dependence of the local deformation of the material. At the same strain amplitude, the plastic deformation becomes more pronounced in the cases of weakly damped dynamics or large time scales of the shear transformation.

Nikolai V. Priezjev

2014-08-28T23:59:59.000Z

105

Solving the two-center nuclear shell-model problem with arbitrarily-orientated deformed potentials  

E-Print Network [OSTI]

A general new technique to solve the two-center problem with arbitrarily-orientated deformed realistic potentials is demonstrated, which is based on the powerful potential separable expansion method. As an example, molecular single-particle spectra for $^{12}$C + $^{12}$C $\\to$ $^{24}$Mg are calculated using deformed Woods-Saxon potentials. These clearly show that non-axial symmetric configurations play a crucial role in molecular resonances observed in reaction processes for this system at low energy.

Alexis Diaz-Torres

2008-10-02T23:59:59.000Z

106

Viscoelastic DampingViscoelastic Damping Characteristics of Indium-Tin/Characteristics of Indium-Tin/SiCSiC  

E-Print Network [OSTI]

1 Viscoelastic DampingViscoelastic Damping Characteristics of Indium-Tin/Characteristics of Indium-Tin Approach: · Based on past experience, indium-tin has well- characterized stiffness/damping. · Fabricate

Swan Jr., Colby Corson

107

Conformal higher-order viscoelastic fluid mechanics  

E-Print Network [OSTI]

We present a generally covariant formulation of conformal higher-order viscoelastic fluid mechanics with strain allowed to take arbitrarily large values. We give a general prescription to determine the dynamics of a relativistic viscoelastic fluid in a way consistent with the hypothesis of local thermodynamic equilibrium and the second law of thermodynamics. We then elaborately study the transient time scales at which the strain almost relaxes and becomes proportional to the gradients of velocity. We particularly show that a conformal second-order fluid with all possible parameters in the constitutive equations can be obtained without breaking the hypothesis of local thermodynamic equilibrium, if the conformal fluid is defined as the long time limit of a conformal second-order viscoelastic system. We also discuss how local thermodynamic equilibrium could be understood in the context of the fluid/gravity correspondence.

Masafumi Fukuma; Yuho Sakatani

2012-05-28T23:59:59.000Z

108

Triaxially deformed relativistic point-coupling model for $?$ hypernuclei: a quantitative analysis of hyperon impurity effect on nuclear collective properties  

E-Print Network [OSTI]

The impurity effect of hyperon on atomic nuclei has received a renewed interest in nuclear physics since the first experimental observation of appreciable reduction of $E2$ transition strength in low-lying states of hypernucleus $^{7}_\\Lambda$Li. Many more data on low-lying states of $\\Lambda$ hypernuclei will be measured soon for $sd$-shell nuclei, providing good opportunities to study the $\\Lambda$ impurity effect on nuclear low-energy excitations. We carry out a quantitative analysis of $\\Lambda$ hyperon impurity effect on the low-lying states of $sd$-shell nuclei at the beyond-mean-field level based on a relativistic point-coupling energy density functional (EDF), considering that the $\\Lambda$ hyperon is injected into the lowest positive-parity ($\\Lambda_s$) and negative-parity ($\\Lambda_p$) states. We adopt a triaxially deformed relativistic mean-field (RMF) approach for hypernuclei and calculate the $\\Lambda$ binding energies of hypernuclei as well as the potential energy surfaces (PESs) in $(\\beta, \\gamma)$ deformation plane. We also calculate the PESs for the $\\Lambda$ hypernuclei with good quantum numbers using a microscopic particle rotor model (PRM) with the same relativistic EDF. The triaxially deformed RMF approach is further applied in order to determine the parameters of a five-dimensional collective Hamiltonian (5DCH) for the collective excitations of triaxially deformed core nuclei. Taking $^{25,27}_{\\Lambda}$Mg and $^{31}_{\\Lambda}$Si as examples, we analyse the impurity effects of $\\Lambda_s$ and $\\Lambda_p$ on the low-lying states of the core nuclei...

W. X. Xue; J. M. Yao; K. Hagino; Z. P. Li; H. Mei; Y. Tanimura

2015-02-18T23:59:59.000Z

109

Propulsion in a viscoelastic fluid Eric Laugaa  

E-Print Network [OSTI]

and a healthy respiratory system.8 Cilia are short flagella which produce fluid motion by means mechanisms and propulsion.9 In the upper respiratory tract, cilia are located in a thin layer of low influenced by viscoelastic stresses. Relevant examples include the ciliary transport of respiratory airway

Lauga, Eric

110

Existence and Regularity for Dynamic Viscoelastic Adhesive Contact with Damage  

SciTech Connect (OSTI)

A model for the dynamic process of frictionless adhesive contact between a viscoelastic body and a reactive foundation, which takes into account the damage of the material resulting from tension or compression, is presented. Contact is described by the normal compliance condition. Material damage is modelled by the damage field, which measures the pointwise fractional decrease in the load-carrying capacity of the material, and its evolution is described by a differential inclusion. The model allows for different damage rates caused by tension or compression. The adhesion is modelled by the bonding field, which measures the fraction of active bonds on the contact surface. The existence of the unique weak solution is established using the theory of set-valued pseudomonotone operators introduced by Kuttler and Shillor (1999). Additional regularity of the solution is obtained when the problem data is more regular and satisfies appropriate compatibility conditions.

Kuttler, Kenneth L. [Department of Mathematics, Brigham Young University, Provo, UT 84602 (United States)], E-mail: klkuttler@math.byu.edu; Shillor, Meir [Department of Mathematics and Statistics, Oakland University, Rochester, MI 48309 (United States)], E-mail: shillor@oakland.edu; Fernandez, Jose R. [Departamento de Matematica Aplicada, Facultade de Matematicas, University of Santiago de Compostela, 15706 Santiago de Compostela (Spain)], E-mail: jramon@usc.es

2006-01-15T23:59:59.000Z

111

Implementation and Evaluation of the Virtual Fields Method: Determining Constitutive Model Parameters From Full-Field Deformation Data.  

SciTech Connect (OSTI)

The Virtual Fields Method (VFM) is an inverse method for constitutive model parameter identication that relies on full-eld experimental measurements of displacements. VFM is an alternative to standard approaches that require several experiments of simple geometries to calibrate a constitutive model. VFM is one of several techniques that use full-eld exper- imental data, including Finite Element Method Updating (FEMU) techniques, but VFM is computationally fast, not requiring iterative FEM analyses. This report describes the im- plementation and evaluation of VFM primarily for nite-deformation plasticity constitutive models. VFM was successfully implemented in MATLAB and evaluated using simulated FEM data that included representative experimental noise found in the Digital Image Cor- relation (DIC) optical technique that provides full-eld displacement measurements. VFM was able to identify constitutive model parameters for the BCJ plasticity model even in the presence of simulated DIC noise, demonstrating VFM as a viable alternative inverse method. Further research is required before VFM can be adopted as a standard method for constitu- tive model parameter identication, but this study is a foundation for ongoing research at Sandia for improving constitutive model calibration.

Kramer, Sharlotte Lorraine Bolyard; Scherzinger, William M.

2014-09-01T23:59:59.000Z

112

Nonlinear viscoelastic materials : bioinspired applications and new characterization measures  

E-Print Network [OSTI]

Viscoelastic materials, such as biomaterials and non-Newtonian fluids, typically experience mechanical loading which evokes a nonlinear rheological response. Rheologically complex materials can provide novel functionality ...

Ewoldt, Randy H. (Randy Harold)

2009-01-01T23:59:59.000Z

113

Kinematic models of deformation in Southern California constrained by geologic and geodetic data  

E-Print Network [OSTI]

Using a standardized fault geometry based on the Community Block Model, we create two analytic block models of the southern California fault system. We constrain one model with only geodetic data. In the other, we assign ...

Eich, Lori A

2006-01-01T23:59:59.000Z

114

Towards the modeling of mucus draining from human lung: role of airways deformation on air-mucus interaction  

E-Print Network [OSTI]

Chest physiotherapy is an empirical technique used to help secretions to get out of the lung whenever stagnation occurs. Although commonly used, little is known about the inner mechanisms of chest physiotherapy and controversies about its use are coming out regularly. Thus, a scientific validation of chest physiotherapy is needed to evaluate its effects on secretions. We setup a quasi-static numerical model of chest physiotherapy based on thorax and lung physiology and on their respective biophysics. We modeled the lung with an idealized deformable symmetric bifurcating tree. Bronchi and their inner fluids mechanics are assumed axisymmetric. Static data from the literature is used to build a model for the lung's mechanics. Secretions motion is the consequence of the shear constraints apply by the air flow. The input of the model is the pressure on the chest wall at each time, and the output is the bronchi geometry and air and secretions properties. In the limit of our model, we mimicked manual and mechanical ...

Mauroy, Benjamin; Pelca, Dominique; Fausser, Christian; Merckx, Jacques; Mitchell, Barrett R

2015-01-01T23:59:59.000Z

115

Deformed shell model results for neutrinoless double beta decay of nuclei in A=60-90 region  

E-Print Network [OSTI]

Nuclear transition matrix elements (NTME) for the neutrinoless double beta decay of $^{70}$Zn, $^{80}$Se and $^{82}$Se nuclei are calculated within the framework of the deformed shell model based on Hartree-Fock states. For $^{70}$Zn, jj44b interaction in $^{2}p_{3/2}$, $^{1}f_{5/2}$, $^{2}p_{1/2}$ and $^{1}g_{9/2}$ space with $^{56}$Ni as the core is employed. However, for $^{80}$Se and $^{82}$Se nuclei, a modified Kuo interaction with the above core and model space are employed. Most of our calculations in this region were performed with this effective interaction. However, jj44b interaction has been found to be better for $^{70}$Zn. The above model space was used in many recent shell model and interacting boson model calculations for nuclei in this region. After ensuring that DSM gives good description of the spectroscopic properties of low-lying levels in these three nuclei considered, the NTME are calculated. The deduced half-lives with these NTME, assuming neutrino mass is 1 eV, are $1.1 \\times 10^{26}$ yr, $2.3 \\times 10^{27}$ yr and $2.2 \\times 10^{24}$ yr for $^{70}$Zn, $^{80}$Se and $^{82}$Se, respectively.

R. Sahu; V. K. B. Kota

2015-03-20T23:59:59.000Z

116

N=(0, 2) Deformation of (2, 2) Sigma Models: Geometric Structure, Holomorphic Anomaly and Exact Beta Functions  

E-Print Network [OSTI]

We study N=(0,2) deformed (2,2) two-dimensional sigma models. Such heterotic models were discovered previously on the world sheet of non-Abelian strings supported by certain four-dimensional N=1 theories. We study geometric aspects and holomorphic properties of these models, and derive a number of exact expressions for the beta functions in terms of the anomalous dimensions analogous to the NSVZ beta function in four-dimensional Yang-Mills. Instanton calculus provides a straightforward method for the derivation. The anomalous dimensions are calculated up to two loops implying that one of the beta functions is explicitly known up to three loops. The fixed point in the ratio of the couplings found previously at one loop is not shifted at two loops. We also consider the N=(0,2) supercurrent supermultiplet (the so-called hypercurrent) and its anomalies, as well as the "Konishi anomaly." This gives us another method for finding exact $\\beta$ functions. We prove that despite the chiral nature of the models under consideration quantum loops preserve isometries of the target space.

Jin Chen; Xiaoyi Cui; Mikhail Shifman; Arkady Vainshtein

2014-07-27T23:59:59.000Z

117

Orienting Deformable Polygonal Parts without Sensors  

E-Print Network [OSTI]

actions that, when provided with the geometric description and a deformation model of choice for the part, exploits the deformation and generates a Plan that consists of the shortest sequence of manipulator actions guaranteed to orient the part up...

Kristek, Shawn

2012-02-14T23:59:59.000Z

118

Stresses generated in cooling viscoelastic ice shells: Application to Europa  

E-Print Network [OSTI]

Stresses generated in cooling viscoelastic ice shells: Application to Europa F. Nimmo Department to cooling and the expansion of the shell due to the ice-water volume change. The former effect generates Citation: Nimmo, F. (2004), Stresses generated in cooling viscoelastic ice shells: Application to Europa, J

Nimmo, Francis

119

On the Rheology of Cold Drawing. 11. Viscoelastic Materials*  

E-Print Network [OSTI]

On the Rheology of Cold Drawing. 11. Viscoelastic Materials* BERNARD D. COLEMAN and DANIEL C. NEWMAN Department of Mechanics and Materials Science, Rutgers, The State University of New Jersey viscoelastic materials subject to inhomogeneous stretching. The formulae, which are valid to within an error

120

Fracture induced anisotropy in viscoelastic UNLP, 11 Octubre de 2012  

E-Print Network [OSTI]

Fracture induced anisotropy in viscoelastic media UNLP, 11 Octubre de 2012 . Fracture induced anisotropy in viscoelastic media ­ p. #12;Fractured media. I Fractures are common in the earth's crust due to different factors, for instance, tectonic stresses and natural or artificial hydraulic fracturing caused

Santos, Juan

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121

Viscous and Viscoelastic Potential Flow 1 Viscous and Viscoelastic Potential Flow  

E-Print Network [OSTI]

and Terrence Y. Liao Department of Aerospace Engineering and Mechanics University of Minnesota, Minneapolis, MN of incompressible fluids admit a pressure (Bernoulli) equation when the divergence of the stress is a gradient as in inviscid fluids, viscous fluids, linear viscoelastic fluids and second-order fluids. We show

Joseph, Daniel D.

122

Properties of triaxial, strongly deformed bands in {sup 167}Ta and {sup 167}Lu and the top-on-top model  

SciTech Connect (OSTI)

Based on the particle-rotor model with one particle coupled to a triaxially deformed rotor, the experimental excitation energy relative to a reference E*-aI(I+1) and the ratio between interband and intraband electromagnetic transitions are well reproduced for {sup 167}Ta with {gamma}=19 deg. The same parameter set for the angular-momentum-dependent rigid-body moments of inertia attains good agreement with experimental data for the positive-parity triaxial, strongly deformed (TSD) band levels in {sup 167}Lu. An attempt is made to investigate the negative-parity TSD band in {sup 167}Lu.

Sugawara-Tanabe, Kazuko [Theoretical Nuclear Physics Laboratory, RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan); Otsuma Women's University, Tama, Tokyo 206-8540 (Japan); Tanabe, Kosai [Theoretical Nuclear Physics Laboratory, RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan); Department of Physics, Saitama University, Sakura-Ku, Saitama 338-8570 (Japan)

2010-11-15T23:59:59.000Z

123

PLASTIC DEFORMATIONPLASTIC DEFORMATION Modes of Deformation  

E-Print Network [OSTI]

PLASTIC DEFORMATIONPLASTIC DEFORMATION Modes of Deformation The Uniaxial Tension Test Mechanisms underlying Plastic Deformation Strengthening mechanisms Mechanical Metallurgy George E Dieter McClick here to know about all the mechanisms by which materials fail #12;Slip (Dislocation motion) Plastic

Subramaniam, Anandh

124

The Asperity-deformation Model Improvements and Its Applications to Velocity Inversion  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . 2 1.2.1 Fracture modeling . . . . . . . . . . . . . . . . . . 3 1.2.2 Thelinkbetweenfracturecharacterizationand seismic data . . . . . . . . . . . . . . . . . . . . . 4 1.2.3 Seismic modeling of CO2 sequestration in frac- tured reservoirs... . . . . . . . . . . . . . . . . . . . 6 1.2.4 The influence of pressure . . . . . . . . . . . . . . 7 1.3 Research objectives . . . . . . . . . . . . . . . . . . . . 8 1.4 Dissertation outline . . . . . . . . . . . . . . . . . . . . 9 1.4.1 Chapter II - Theoretical study of the asperity...

Bui, Hoa Q.

2010-01-16T23:59:59.000Z

125

Molecular motors transporting cargos in viscoelastic cytosol: how to beat subdiffusion with a power stroke?  

E-Print Network [OSTI]

Anomalously slow passive diffusion, $\\langle \\delta x^2(t)\\rangle\\simeq t^{\\alpha}$, with $0<\\alpha<1$, of larger tracers such as messenger RNA and endogenous submicron granules in the cytoplasm of living biological cells has been demonstrated in a number of experiments and has been attributed to the viscoelastic physical nature of the cellular cytoplasm. This finding provokes the question to which extent active intracellular transport is affected by this viscoelastic environment: does the subdiffusion of free submicron cargo such as vesicles and organelles always imply anomalously slow transport by molecular motors such as kinesins, that is, directed transport characterized by a sublinear growth of the mean distance, $\\langle x(t)\\rangle\\simeq t^{\\alpha_{\\rm eff}}$, with $0<\\alpha_{\\rm eff}<1$? Here we study a generic model approach combining the commonly accepted two-state Brownian ratchet model of kinesin motors based on the continuous-state diffusion along microtubule driven by a flashing bind...

Goychuk, Igor; Metzler, Ralf

2013-01-01T23:59:59.000Z

126

A comparison of current work-hardening models used in the analysis of plastic deformations  

E-Print Network [OSTI]

stress-strain curve, 6061-T6 aluminum. 91 15 Uniaxial reversed loading of 6061-T6 aluminum, isotropic hardening 92 16 Uniaxial reversed loading of 6061-T6 aluminum, kinematic hardening 93 17 Uniaxial reversed loading of 6061-T6 aluminum, mechanical... sublayer model (4 sublayers) 94 viii LIST OF FIGURES (Continued) FIGURE PAGE 18 Uniaxial reversed loading of 6061-T6 aluminum, mechanical sublayer model (2 sublayers) 95 19 Uniaxial reversed loading of 6061-T6 aluminum, Mroz model (4 work hardening...

Vaughn, David Kenneth

1973-01-01T23:59:59.000Z

127

Constitutive modeling of the finite deformation behavior of membranes possessing a triangulated networked microstructure  

E-Print Network [OSTI]

Many biological, natural and synthetic materials possess a networked or micro-truss-like microstructure. In this thesis work, a general microstructurally-informed continuum level constitutive model of the large stretch ...

Arslan, Melis

2005-01-01T23:59:59.000Z

128

Deformed shell model results for neutrinoless double beta decay of nuclei in A=60-90 region  

E-Print Network [OSTI]

Nuclear transition matrix elements (NTME) for the neutrinoless double beta decay of $^{70}$Zn, $^{80}$Se and $^{82}$Se nuclei are calculated within the framework of the deformed shell model based on Hartree-Fock states. For $^{70}$Zn, jj44b interaction in $^{2}p_{3/2}$, $^{1}f_{5/2}$, $^{2}p_{1/2}$ and $^{1}g_{9/2}$ space with $^{56}$Ni as the core is employed. However, for $^{80}$Se and $^{82}$Se nuclei, a modified Kuo interaction with the above core and model space are employed. Most of our calculations in this region were performed with this effective interaction. However, jj44b interaction has been found to be better for $^{70}$Zn. After ensuring that DSM gives good description of the spectroscopic properties of low-lying levels in these three nuclei considered, the NTME are calculated. The deduced half-lives with these NTME, assuming neutrino mass is 1 eV, are $9.6 \\times 10^{25}$yr, $1.9 \\times 10^{27}$yr and $1.95 \\times 10^{24}$yr for $^{70}$Zn, $^{80}$Se and $^{82}$Se, respectively.

R. Sahu; V. K. B. Kota

2014-09-17T23:59:59.000Z

129

Deformed shell model results for neutrinoless double beta decay of nuclei in A=60-90 region  

E-Print Network [OSTI]

Nuclear transition matrix elements (NTME) for the neutrinoless double beta decay of $^{70}$Zn, $^{80}$Se and $^{82}$Se nuclei are calculated within the framework of the deformed shell model based on Hartree-Fock states. For $^{70}$Zn, jj44b interaction in $^{2}p_{3/2}$, $^{1}f_{5/2}$, $^{2}p_{1/2}$ and $^{1}g_{9/2}$ space with $^{56}$Ni as the core is employed. However, for $^{80}$Se and $^{82}$Se nuclei, a modified Kuo interaction with the above core and model space are employed. Most of our calculations in this region were performed with this effective interaction. However, jj44b interaction has been found to be better for $^{70}$Zn. After ensuring that DSM gives good description of the spectroscopic properties of low-lying levels in these three nuclei considered, the NTME are calculated. The deduced half-lives with these NTME, assuming neutrino mass is 1 eV, are $9.6 \\times 10^{25}$yr, $1.9 \\times 10^{27}$yr and $1.95 \\times 10^{24}$yr for $^{70}$Zn, $^{80}$Se and $^{82}$Se, respectively.

Sahu, R

2014-01-01T23:59:59.000Z

130

Form factors in sinh- and sine-Gordon models, deformed Virasoro algebra, Macdonald polynomials and resonance identities  

E-Print Network [OSTI]

We continue the study of form factors of descendant operators in the sinh- and sine-Gordon models in the framework of the algebraic construction proposed in [arXiv:0812.4776]. We find the algebraic construction to be related to a particular limit of the tensor product of the deformed Virasoro algebra and a suitably chosen Heisenberg algebra. To analyze the space of local operators in the framework of the form factor formalism we introduce screening operators and construct singular and cosingular vectors in the Fock spaces related to the free field realization of the obtained algebra. We show that the singular vectors are expressed in terms of the degenerate Macdonald polynomials with rectangular partitions. We study the matrix elements that contain a singular vector in one chirality and a cosingular vector in the other chirality and find them to lead to the resonance identities already known in the conformal perturbation theory. Besides, we give a new derivation of the equation of motion in the sinh-Gordon theory, and a new representation for conserved currents.

Michael Lashkevich; Yaroslav Pugai

2014-07-28T23:59:59.000Z

131

Form factors in sinh- and sine-Gordon models, deformed Virasoro algebra, Macdonald polynomials and resonance identities  

E-Print Network [OSTI]

We continue the study of form factors of descendant operators in the sinh- and sine-Gordon models in the framework of the algebraic construction proposed in [arXiv:0812.4776]. We find the algebraic construction to be related to a particular limit of the tensor product of the deformed Virasoro algebra and a suitably chosen Heisenberg algebra. To analyze the space of local operators in the framework of the form factor formalism we introduce screening operators and construct singular and cosingular vectors in the Fock spaces related to the free field realization of the obtained algebra. We show that the singular vectors are expressed in terms of the degenerate Macdonald polynomials with rectangular partitions. We study the matrix elements that contain a singular vector in one chirality and a cosingular vector in the other chirality and find them to lead to the resonance identities already known in the conformal perturbation theory. Besides, we give a new derivation of the equation of motion in the sinh-Gordon th...

Lashkevich, Michael

2013-01-01T23:59:59.000Z

132

Coupled Flow and Deformation Modeling of Carbon Dioxide Migration in the Presence of a Caprock Fracture during Injection  

SciTech Connect (OSTI)

Understanding the transport of carbon dioxide (CO{sub 2}) during long-term CO{sub 2} injection into a typical geologic reservoir, such as a saline aquifer, could be complicated because of changes in geochemical, hydrogeological, and hydromechanical behavior. While the caprock layer overlying the target aquifer is intended to provide a tight, impermeable seal in securing injected CO{sub 2}, the presence of geologic uncertainties, such as a caprock fracture or fault, may provide a channel for CO{sub 2} leakage. There could also be a possibility of the activation of a new or existing dormant fault or fracture, which could act as a leakage pathway. Such a leakage event during CO{sub 2} injection may lead to a different pressure and ground response over a period of time. In the present study, multiphase fluid flow simulations in porous media coupled with geomechanics were used to investigate the overburden geologic response and plume behavior during CO{sub 2} injection in the presence of a hypothetical permeable fractured zone in a caprock, existing or activated. Both single-phase and multiphase fluid flow simulations were performed. The CO{sub 2} migration through an existing fractured zone leads to changes in the fluid pressure in the overburden geologic layers and could have a significant impact on ground deformation behavior. Results of the study show that pressure signatures and displacement patterns are significantly different in the presence of a fractured zone in the caprock layer. The variation in pressure and displacement signatures because of the presence of a fractured zone in the caprock at different locations may be useful in identifying the presence of a fault/fractured zone in the caprock. The pressure signatures can also serve as a mechanism to identify the activation of leakage pathways through the caprock during CO{sub 2} injection. Pressure response and ground deformation behavior from sequestration modeling could be useful in the development of smart technologies to monitor safe CO{sub 2} storage and understand CO{sub 2} transport, with limited field instrumentation.

Siriwardane, Hema J.; Gondle, Raj K.; Bromhal, Grant S.

2013-08-01T23:59:59.000Z

133

Experimental investigation and constitutive modeling of the large deformation behavior of anisotropic steel sheets undergoing strain-induced phase transformation  

E-Print Network [OSTI]

The strain-induced phase transformation from austenite to martensite is responsible for the high strength and ductility of TRansformation-Induced Plasticity (TRIP)- assisted steels. The large deformation behavior of ...

Beese, Allison M

2011-01-01T23:59:59.000Z

134

Visco-elastic fluid simulations of coherent structures in strongly coupled dusty plasma medium  

SciTech Connect (OSTI)

A generalized hydrodynamic model depicting the behaviour of visco-elastic fluids has often been invoked to explore the behaviour of a strongly coupled dusty plasma medium below their crystallization limit. The model has been successful in describing the collective normal modes of the strongly coupled dusty plasma medium observed experimentally. The paper focuses on the study of nonlinear dynamical characteristic features of this model. Specifically, the evolution of coherent vorticity patches is being investigated here within the framework of this model. A comparison with Newtonian fluids and molecular dynamics simulations treating the dust species interacting through the Yukawa potential has also been presented.

Singh Dharodi, Vikram; Kumar Tiwari, Sanat; Das, Amita, E-mail: amita@ipr.res.in [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

2014-07-15T23:59:59.000Z

135

Viscoelastic transient of confined Red Blood Cells  

E-Print Network [OSTI]

The unique ability of a red blood cell to flow through extremely small microcapillaries depends on the viscoelastic properties of its membrane. Here, we study in vitro the response time upon flow startup exhibited by red blood cells confined into microchannels. We show that the characteristic transient time depends on the imposed flow strength, and that such a dependence gives access to both the effective viscosity and the elastic modulus controlling the temporal response of red cells. A simple theoretical analysis of our experimental data, validated by numerical simulations, further allows us to compute an estimate for the two-dimensional membrane viscosity of red blood cells, $\\eta_{mem}^{2D}\\sim 10^{-7}$ N$\\cdot$s$\\cdot$m$^{-1}$. By comparing our results with those from previous studies, we discuss and clarify the origin of the discrepancies found in the literature regarding the determination of $\\eta_{mem}^{2D}$, and reconcile seemingly conflicting conclusions from previous works.

Gaël Prado; Alexander Farutin; Chaouqi Misbah; Lionel Bureau

2014-09-17T23:59:59.000Z

136

Measuring the viscoelastic properties of polytetrafluoroethylene copolymers at ultrasonic frequencies  

E-Print Network [OSTI]

properties must be measured directly. A new technique employing a piezoelectric ultrasonic composite oscillator has been developed to measure the viscoelastic properties, GI(w) and G"(w), of Tefzel 280 (a high molecular weight copolymer of ethylene...

Thomas, Verghese

1994-01-01T23:59:59.000Z

137

Multinozzle printheads for 3D printing of viscoelastic inks.  

E-Print Network [OSTI]

??A high-pressure microfluidic device for 3D extrusion printing of viscoelastic ink was developed. The device was machined out of poly(methylmethacrylate) (PMMA) using a 3-axis CNC… (more)

Kranz, Stephen

2013-01-01T23:59:59.000Z

138

VISCOELASTICITY OF BIOPOLYMER NETWORKS AND STATISTICAL MECHANICS OF  

E-Print Network [OSTI]

VISCOELASTICITY OF BIOPOLYMER NETWORKS AND STATISTICAL MECHANICS OF SEMIFLEXIBLE POLYMERS Erwin scattering . . . . . . . . . . . . . . . . . 11 II.C.2 Colloidal probes and micro-rheology . . . . . . . . . . . 14 IIIVISCOELASTICTY OF BIOPOLYMER NETWORKS 15 III.AExperimental techniques and results

Frey, Erwin

139

Nonlinear viscoelastic characterization of thin films using dynamic mechanical analysis  

E-Print Network [OSTI]

NONLINEAR VISCOELASTIC CHARACTERIZATION OF THIN FILMS USING DYNAMIC MECHANICAL ANALYSIS A Thesis by DEBBIE FLOWERS PAYNE Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE AUGUST 1993 Major Subject: Aerospace Engineering NONLINEAR VISCOELASTIC CHARACTERIZATION OF THIN FILMS USING DYNAMIC MECHANICAL ANALYSIS A Thesis by DEBBIE FLOWERS PAYNE Approved as to style and content by: Thomas W...

Payne, Debbie Flowers

1993-01-01T23:59:59.000Z

140

Direct Rendering of Deformable Volume Data Shiaofen Fang  

E-Print Network [OSTI]

Direct Rendering of Deformable Volume Data Shiaofen Fang Department of Computer and Information In this paper, we present a new deformable volume rendering algorithm. The volume deformation is modeled to directly render the deformed volume without going through the expensive volume construction process

Fang, Shiaofen

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Analysis, comparison, and modeling of radar interferometry, date of surface deformation signals associated with underground explosions, mine collapses and earthquakes. Phase I: underground explosions, Nevada Test Site  

SciTech Connect (OSTI)

We have previously presented simple elastic deformation modeling results for three classes of seismic events of concern in monitoring the CTBT--underground explosions, mine collapses and earthquakes. Those results explored the theoretical detectability of each event type using synthetic aperture radar interferometry (InSAR) based on commercially available satellite data. In those studies we identified and compared the characteristics of synthetic interferograms that distinguish each event type, as well the ability of the interferograms to constrain source parameters. These idealized modeling results, together with preliminary analysis of InSAR data for the 1995 mb 5.2 Solvay mine collapse in southwestern Wyoming, suggested that InSAR data used in conjunction with regional seismic monitoring holds great potential for CTBT discrimination and seismic source analysis, as well as providing accurate ground truth parameters for regional calibration events. In this paper we further examine the detectability and ''discriminating'' power of InSAR by presenting results from InSAR data processing, analysis and modeling of the surface deformation signals associated with underground explosions. Specifically, we present results of a detailed study of coseismic and postseismic surface deformation signals associated with underground nuclear and chemical explosion tests at the Nevada Test Site (NTS). Several interferograms were formed from raw ERS-1/2 radar data covering different time spans and epochs beginning just prior to the last U.S. nuclear tests in 1992 and ending in 1996. These interferograms have yielded information about the nature and duration of the source processes that produced the surface deformations associated with these events. A critical result of this study is that significant post-event surface deformation associated with underground nuclear explosions detonated at depths in excess of 600 meters can be detected using differential radar interferometry. An immediate implication of this finding is that underground nuclear explosions may not need to be captured coseismically by radar images acquired before and after an event in order to be detectable. This has obvious advantages in CTBT monitoring since suspect seismic events--which usually can be located within a 100 km by 100 km area of an ERS-1/2 satellite frame by established seismic methods-can be imaged after the event has been identified and located by existing regional seismic networks. Key Words: InSAR, SLC images, interferogram, synthetic interferogram, ERS-1/2 frame, phase unwrapping, DEM, coseismic, postseismic, source parameters.

Foxall, W; Vincent, P; Walter, W

1999-07-23T23:59:59.000Z

142

Rolling friction for hard cylinder and sphere on viscoelastic solid  

E-Print Network [OSTI]

We calculate the friction force acting on a hard cylinder or spherical ball rolling on a flat surface of a viscoelastic solid. The rolling friction coefficient depends non-linearly on the normal load and the rolling velocity. For a cylinder rolling on a viscoelastic solid characterized by a single relaxation time Hunter has obtained an exact result for the rolling friction, and our result is in very good agreement with his result for this limiting case. The theoretical results are also in good agreement with experiments of Greenwood and Tabor. We suggest that measurements of rolling friction over a wide range of rolling velocities and temperatures may constitute an useful way to determine the viscoelastic modulus of rubber-like materials.

B. N. J. Persson

2010-08-26T23:59:59.000Z

143

Guided Wave Propagation in Tubular Section with Multi-Layered Viscoelastic Coating  

E-Print Network [OSTI]

cross-section of the pipe. The layer between radii r1 and r2 is elastic. The outer layer between radii r2 and r3 is the viscoelastic coating material. The axial direction of the cylinder is along the z-axis. The circumferential direction is defined... by the ?-axis. Fig. 2.1 Pipe model Fig. 2.2 Pipe cross-section 2.1. Longitudinal Wave along Axial Direction The Lame-Navier equation of motion for isotropic materials is 2 2 2( ) ( ) ( / )? ? ? ?? + + ? ?? = ? ? tu u u (2.1) r3 r2 r1...

Kuo, Chi-Wei 1982-

2012-11-16T23:59:59.000Z

144

An interactive deformation technique with triangles and distance functions  

E-Print Network [OSTI]

stiA' or rigid models can be made to look Fig. 15. Four triangle deformers used together in 3D. organic. Figure 16 is a fairly complicated 3D model of a castle. After deformation, the castle looks organic and elastic. Deformation can breathe life...

Palmer, James Dean

2012-06-07T23:59:59.000Z

145

Dynamics of multiple viscoelastic carbon nanotube based nanocomposites with axial magnetic field  

SciTech Connect (OSTI)

Nanocomposites and magnetic field effects on nanostructures have received great attention in recent years. A large amount of research work was focused on developing the proper theoretical framework for describing many physical effects appearing in structures on nanoscale level. Great step in this direction was successful application of nonlocal continuum field theory of Eringen. In the present paper, the free transverse vibration analysis is carried out for the system composed of multiple single walled carbon nanotubes (MSWCNT) embedded in a polymer matrix and under the influence of an axial magnetic field. Equivalent nonlocal model of MSWCNT is adopted as viscoelastically coupled multi-nanobeam system (MNBS) under the influence of longitudinal magnetic field. Governing equations of motion are derived using the Newton second low and nonlocal Rayleigh beam theory, which take into account small-scale effects, the effect of nanobeam angular acceleration, internal damping and Maxwell relation. Explicit expressions for complex natural frequency are derived based on the method of separation of variables and trigonometric method for the “Clamped-Chain” system. In addition, an analytical method is proposed in order to obtain asymptotic damped natural frequency and the critical damping ratio, which are independent of boundary conditions and a number of nanobeams in MNBS. The validity of obtained results is confirmed by comparing the results obtained for complex frequencies via trigonometric method with the results obtained by using numerical methods. The influence of the longitudinal magnetic field on the free vibration response of viscoelastically coupled MNBS is discussed in detail. In addition, numerical results are presented to point out the effects of the nonlocal parameter, internal damping, and parameters of viscoelastic medium on complex natural frequencies of the system. The results demonstrate the efficiency of the suggested methodology to find the closed form solutions for the free vibration response of multiple nanostructure systems under the influence of magnetic field.

Karli?i?, Danilo; Caji?, Milan [Mathematical Institute of the SASA, Kneza Mihaila 36, Belgrade 11001 (Serbia); Murmu, Tony [School of Engineering, University of the West of Scotland, Paisley PA12BE (United Kingdom); Kozi?, Predrag [Faculty of Mechanical Engineering, University of Niš, A. Medvedeva 14, 18000 Niš (Serbia); Adhikari, Sondipon [College of Engineering, Swansea University, Singleton Park, Swansea SA2 8PP (United Kingdom)

2014-06-21T23:59:59.000Z

146

Viscoelastic Properties of an Epoxy Resin during Cure  

E-Print Network [OSTI]

Viscoelastic Properties of an Epoxy Resin during Cure DANIEL J. O'BRIEN1 Department of Mechanical: The cure dependent relaxation modulus of an epoxy resin was investigated over the entire range of cure as well as thermal asymmetry can result in uneven curing of the part. Second, epoxy resins can shrink

Mather, Patrick T.

147

Shape Recovery of Viscoelastic Deployable Structures and Sergio Pellegrino  

E-Print Network [OSTI]

and opposite sense folding. I. Introduction Deployable structures made of thin carbon fiber reinforced polymerShape Recovery of Viscoelastic Deployable Structures Kawai Kwok and Sergio Pellegrino California Institute of Technology, Pasadena, CA 91125 The paper investigates the shape recovery behavior of a simple

Pellegrino, Sergio

148

Propagation and Retention of Viscoelastic Surfactants in Carbonate Cores  

E-Print Network [OSTI]

Viscoelastic surfactant have found numerous application in the oil fields as fracturing and matrix acidizing fluid additives in the recent years. They have the ability to form long worm-like micelles with the increase in pH and calcium concentration...

Yu, Meng

2012-07-16T23:59:59.000Z

149

Helicobacter pylori moves through mucus by reducing mucin viscoelasticity  

E-Print Network [OSTI]

Helicobacter pylori moves through mucus by reducing mucin viscoelasticity Jonathan P. Celli: 20 pages 6 figures 0 tables. #12;Abstract The ulcer-causing gastric pathogen Helicobacter pylori is wrong. #12;\\body Introduction Helicobacter pylori is a spiral shaped, Gram-negative microorganism

150

Helicobacter pylori moves through mucus by reducing mucin viscoelasticity  

E-Print Network [OSTI]

Helicobacter pylori moves through mucus by reducing mucin viscoelasticity Jonathan P. Cellia,1, 2009 (received for review March 27, 2009) The ulcer-causing gastric pathogen Helicobacter pylori environment. H. pylori bacterial motility rheology pH gelation Helicobacter pylori is a spiral shaped, Gram

151

Changes in Large Pulmonary Arterial Viscoelasticity in Chronic Pulmonary Hypertension  

E-Print Network [OSTI]

Changes in Large Pulmonary Arterial Viscoelasticity in Chronic Pulmonary Hypertension Zhijie Wang1 of pulmonary arterial hypertension (PAH) and is an excellent predictor of mortality due to right ventricular at a physiologically relevant frequency (10 Hz) in hypertensive PAs. The dynamic elastic modulus (E), a material

Lakes, Roderic

152

ANALYSES OF DEFORMATION IN VISCOELASTIC SANDWICH COMPOSITES SUBJECT TO MOISTURE DIFFUSION  

E-Print Network [OSTI]

Sandwich composites with polymer foam core are currently used in load-bearing components in buildings and naval structures due to their high strength to weight and stiffness to weight ratios, excellent thermal insulation, and ease of manufacturing...

Joshi, Nikhil P.

2010-01-16T23:59:59.000Z

153

Application of the multi-mechanism deformation model for three-dimensional simulations of salt : behavior for the strategic petroleum reserve.  

SciTech Connect (OSTI)

The U.S. Strategic Petroleum Reserve stores crude oil in 62 solution-mined caverns in salt domes located in Texas and Louisiana. Historically, three-dimensional geomechanical simulations of the behavior of the caverns have been performed using a power law creep model. Using this method, and calibrating the creep coefficient to field data such as cavern closure and surface subsidence, has produced varying degrees of agreement with observed phenomena. However, as new salt dome locations are considered for oil storage facilities, pre-construction geomechanical analyses are required that need site-specific parameters developed from laboratory data obtained from core samples. The multi-mechanism deformation (M-D) model is a rigorous mathematical description of both transient and steady-state creep phenomena. Recent enhancements to the numerical integration algorithm within the model have created a more numerically stable implementation of the M-D model. This report presents computational analyses to compare the results of predictions of the geomechanical behavior at the West Hackberry SPR site using both models. The recently-published results using the power law creep model produced excellent agreement with an extensive set of field data. The M-D model results show similar agreement using parameters developed directly from laboratory data. It is also used to predict the behavior for the construction and operation of oil storage caverns at a new site, to identify potential problems before a final cavern layout is designed.

Ehgartner, Brian L.; Sobolik, Steven Ronald; Bean, James E.

2010-07-01T23:59:59.000Z

154

Refined Cigar and Omega-deformed Conifold  

E-Print Network [OSTI]

Antoniadis et al proposed a relation between the Omega-deformation and refined correlation functions of the topological string theory. We investigate the proposal for the deformed conifold geometry from a non-compact Gepner model approach. The topological string theory on the deformed conifold has a dual description in terms of the c=1 non-critical string theory at the self-dual radius, and the Omega-deformation yields the radius deformation. We show that the refined correlation functions computed from the twisted SL(2,R)/U(1) Kazama-Suzuki coset model at level k=1 have direct c=1 non-critical string theory interpretations. After subtracting the leading singularity to procure the 1PI effective action, we obtain the agreement with the proposal.

Yu Nakayama

2010-07-30T23:59:59.000Z

155

IBA in deformed nuclei  

SciTech Connect (OSTI)

The structure and characteristic properties and predictions of the IBA in deformed nuclei are reviewed, and compared with experiment, in particular for /sup 168/Er. Overall, excellent agreement, with a minimum of free parameters (in effect, two, neglecting scale factors on energy differences), was obtained. A particularly surprising, and unavoidable, prediction is that of strong ..beta.. ..-->.. ..gamma.. transitions, a feature characteristically absent in the geometrical model, but manifest empirically. Some discrepancies were also noted, principally for the K=4 excitation, and the detailed magnitudes of some specific B(E2) values. Considerable attention is paid to analyzing the structure of the IBA states and their relation to geometric models. The bandmixing formalism was studied to interpret both the aforementioned discrepancies and the origin of the ..beta.. ..-->.. ..gamma.. transitions. The IBA states, extremely complex in the usual SU(5) basis, are transformed to the SU(3) basis, as is the interaction Hamiltonian. The IBA wave functions appear with much simplified structure in this way as does the structure of the associated B(E2) values. The nature of the symmetry breaking of SU(3) for actual deformed nuclei is seen to be predominantly ..delta..K=0 mixing. A modified, and more consistent, formalism for the IBA-1 is introduced which is simpler, has fewer free parameters (in effect, one, neglecting scale factors on energy differences), is in at least as good agreement with experiment as the earlier formalism, contains a special case of the 0(6) limit which corresponds to that known empirically, and appears to have a close relationship to the IBA-2. The new formalism facilitates the construction of contour plots of various observables (e.g., energy or B(E2) ratios) as functions of N and chi/sub Q/ which allow the parameter-free discussion of qualitative trajectories or systematics.

Casten, R.F.; Warner, D.D.

1982-01-01T23:59:59.000Z

156

E-Print Network 3.0 - axially accelerating viscoelastic Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

(i.e. damped oscillations) are observed... to rapidly estimate viscoelastic properties. Creep ringing can be deliberately exploited to ... Source: McKinley, Gareth H.- Department...

157

Deformed proton emitters.  

SciTech Connect (OSTI)

The mechanisms of proton radioactivity from deformed rare earth nuclei are discussed and preliminary results on the fine structure decay of {sup 131}Eu are presented.

Carpenter, M. P.; Cizewski, J. A.; Davids, C. N.; Davinson, T.; Fotiades, N.; Henderson, D. J.; Janssens, R. V. F.; Lauritsen, T.; Reiter, P.; Ressler, J. J.; Schwartz, J.; Seweryniak, D.; Sonzogni, A. A.; Uusitalok, J.; Walters, W. B.; Wiedenhover, I. L.; Woods, P. J.

1999-02-17T23:59:59.000Z

158

Analysis of Refrigerant Flow and Deformation for a Flexible Short-Tube using a Finite Element Model  

E-Print Network [OSTI]

reliability. Short-tubes have either a constant inner dia- meter flow channel or a tapered channel with a smallAbstract A finite element model was used to simulate single-phase flow of R-22 through flexible short-tubes. The numerical model included the fluid... in the flow area. The more flexible (5513 kPa) short-tube restricted the mass flow rate more than the most rigid (9889 kPa) short-tube used in this study. The mass flow rates estimated with the finite element model were as much as 14% higher than those from...

O'Neal, D.L.; Bassiouny, R.

159

Resurgent deformation quantisation  

SciTech Connect (OSTI)

We construct a version of the complex Heisenberg algebra based on the idea of endless analytic continuation. The algebra would be large enough to capture quantum effects that escape ordinary formal deformation quantisation. -- Highlights: •We construct resurgent deformation quantisation. •We give integral formulæ. •We compute examples which show that hypergeometric functions appear naturally in quantum computations.

Garay, Mauricio, E-mail: garay91@gmail.com [Institut für Mathematik, FB 08 Physik, Mathematik und Informatik, Johannes Gutenberg-Universität, 55099 Mainz (Germany)] [Institut für Mathematik, FB 08 Physik, Mathematik und Informatik, Johannes Gutenberg-Universität, 55099 Mainz (Germany); Goursac, Axel de, E-mail: Axelmg@melix.net [Chargé de Recherche au F.R.S.-FNRS, IRMP, Université Catholique de Louvain, Chemin du Cyclotron, 2, B-1348 Louvain-la-Neuve (Belgium); Straten, Duco van, E-mail: straten@mathematik.uni-mainz.de [Institut für Mathematik, FB 08 Physik, Mathematik und Informatik, Johannes Gutenberg-Universität, 55099 Mainz (Germany)

2014-03-15T23:59:59.000Z

160

Tumor Tracking Method Based on a Deformable 4D CT Breathing Motion Model Driven by an External Surface Surrogate  

SciTech Connect (OSTI)

Purpose: To develop a tumor tracking method based on a surrogate-driven motion model, which provides noninvasive dynamic localization of extracranial targets for the compensation of respiration-induced intrafraction motion in high-precision radiation therapy. Methods and Materials: The proposed approach is based on a patient-specific breathing motion model, derived a priori from 4-dimensional planning computed tomography (CT) images. Model parameters (respiratory baseline, amplitude, and phase) are retrieved and updated at each treatment fraction according to in-room radiography acquisition and optical surface imaging. The baseline parameter is adapted to the interfraction variations obtained from the daily cone beam (CB) CT scan. The respiratory amplitude and phase are extracted from an external breathing surrogate, estimated from the displacement of the patient thoracoabdominal surface, acquired with a noninvasive surface imaging device. The developed method was tested on a database of 7 lung cancer patients, including the synchronized information on internal and external respiratory motion during a CBCT scan. Results: About 30 seconds of simultaneous acquisition of CBCT and optical surface images were analyzed for each patient. The tumor trajectories identified in CBCT projections were used as reference and compared with the target trajectories estimated from surface displacement with the a priori motion model. The resulting absolute differences between the reference and estimated tumor motion along the 2 image dimensions ranged between 0.7 and 2.4 mm; the measured phase shifts did not exceed 7% of the breathing cycle length. Conclusions: We investigated a tumor tracking method that integrates breathing motion information provided by the 4-dimensional planning CT with surface imaging at the time of treatment, representing an alternative approach to point-based external–internal correlation models. Although an in-room radiograph-based assessment of the reliability of the motion model is envisaged, the developed technique does not involve the estimation and continuous update of correlation parameters, thus requiring a less intense use of invasive imaging.

Fassi, Aurora, E-mail: aurora.fassi@mail.polimi.it [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Schaerer, Joël; Fernandes, Mathieu [CREATIS, CNRS UMR 5220, INSERM U1044, Université Lyon 1, INSA-Lyon, Villeurbanne (France); Department of Radiotherapy, Centre Léon Bérard, Lyon (France); Riboldi, Marco [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Bioengineering Unit, CNAO Foundation, Pavia (Italy); Sarrut, David [CREATIS, CNRS UMR 5220, INSERM U1044, Université Lyon 1, INSA-Lyon, Villeurbanne (France); Department of Radiotherapy, Centre Léon Bérard, Lyon (France); Baroni, Guido [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Bioengineering Unit, CNAO Foundation, Pavia (Italy)

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Tension Dynamics and Linear Viscoelastic Behavior of a Single Semiflexible Polymer Chain  

E-Print Network [OSTI]

We study the dynamical response of a single semiflexible polymer chain based on the theory developed by Hallatschek et al. for the wormlike-chain model. The linear viscoelastic response under oscillatory forces acting at the two chain ends is derived analytically as a function of the oscillation frequency . We shall show that the real part of the complex compliance in the low frequency limit is consistent with the static result of Marko and Siggia whereas the imaginary part exhibits the power-law dependence +1/2. On the other hand, these compliances decrease as the power law -7/8 for the high frequency limit. These are different from those of the Rouse dynamics. A scaling argument is developed to understand these novel results.

T. Hiraiwa; T. Ohta

2009-03-12T23:59:59.000Z

162

Abatement of mixing in shear-free elongationally unstable viscoelastic microflows  

E-Print Network [OSTI]

The addition of minute amounts of chemically inert polyacrylamide polymer to liquids results in large instabilities under steady electro-osmotic pumping through 2:1 constrictions, demonstrating that laminar flow conditions can be broken in electro-osmotic flow of viscoelastic material. By excluding shear and imposing symmetry we create a platform where only elongational viscoelastic instabilities, and diffusion, affect mixing. In contrast to earlier studies with significant shear that found up to orders of magnitude increase in mixing we find that inclusion of polymers excites large viscoelastic instabilities yet mixing is reduced relative to polymer-free liquids. The absolute decrease in mixing we find is consistent with the understanding that adding polymer increases viscosity while viscoelastic flows progress towards elastic turbulence, a type of mild (Batchelor) turbulence, and indicates that electro-osmotic pumped devices are an ideal platform for studying viscoelastic instabilities without supplementary factors.

R. M. Bryce; M. R. Freeman

2010-02-08T23:59:59.000Z

163

A comparison of viscoelastic stress wakes for 2D and 3D Newtonian drop deformation in a viscoelastic matrix under shear  

E-Print Network [OSTI]

], Webster [We2], Faran [Fa1], and Cima-Suffridge [CS1]. In the first part of this thesis (Chapter 2), we

Renardy, Yuriko

164

Viscoelastic{Viscoplastic Damage Model for Asphalt Concrete  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.2.1 Yield surface . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2.2.2 Viscoplastic potential energy function . . . . . . . . . . . . . . 23 2.2.3 Hardening function . . . . . . . . . . . . . . . . . . . . . . . . 23 2.3 Numerical... viii LIST OF FIGURES FIGURE Page 1.1 Moisture-induced damage in pavements results in raveling and potholing 4 1.2 Adhesive and cohesive failure . . . . . . . . . . . . . . . . . . . . . . . 5 1.3 Damaged and e ective undamaged con gurations...

Graham, Michael A.

2010-10-12T23:59:59.000Z

165

A micromechanical model for a viscoelastic cohesive zone  

E-Print Network [OSTI]

. This leads to the general form for the internal variable evolution law, dct = f(uk) on BQ, (3, 7) Initial and Boundary Conditions. The initial values for all the state variables are assumed to be zero, i. e. o, ?(x?t= 0) s?(x?, t= 0) u, (xr, t= 0) = 0... in B and on OQ (3 g) where x, and t represent the spatial coordinate within the body and time, respectively. Also, both tractions and displacements are specifted on the body. These mixed boundary conditions are: T, (x?t) = T, u, (x?, t) = u, on c...

Searcy, Chad Randall, 1972-

1998-01-01T23:59:59.000Z

166

Contractions, deformations and curvature  

E-Print Network [OSTI]

The role of curvature in relation with Lie algebra contractions of the pseudo-ortogonal algebras so(p,q) is fully described by considering some associated symmetrical homogeneous spaces of constant curvature within a Cayley-Klein framework. We show that a given Lie algebra contraction can be interpreted geometrically as the zero-curvature limit of some underlying homogeneous space with constant curvature. In particular, we study in detail the contraction process for the three classical Riemannian spaces (spherical, Euclidean, hyperbolic), three non-relativistic (Newtonian) spacetimes and three relativistic ((anti-)de Sitter and Minkowskian) spacetimes. Next, from a different perspective, we make use of quantum deformations of Lie algebras in order to construct a family of spaces of non-constant curvature that can be interpreted as deformations of the above nine spaces. In this framework, the quantum deformation parameter is identified as the parameter that controls the curvature of such "quantum" spaces.

Angel Ballesteros; Francisco J. Herranz; Orlando Ragnisco; Mariano Santander

2007-06-15T23:59:59.000Z

167

Nanolaminate deformable mirrors  

DOE Patents [OSTI]

A deformable mirror formed out of two layers of a nanolaminate foil attached to a stiff substrate is introduced. Deformation is provided by an electrostatic force between two of the layers. The internal stiffness of the structure allows for high-spatial-frequency shapes. The nanolaminate foil of the present invention allows for a high-quality mirror surface. The device achieves high precision in the vertical direction by using foils with accurately controlled thicknesses, but does not require high precision in the lateral dimensions, allowing such mirrors to be fabricated using crude lithography techniques. Such techniques allow structures up to about the meter scale to be fabricated.

Papavasiliou, Alexandros P. (Oakland, CA); Olivier, Scot S. (Santa Cruz, CA)

2009-04-14T23:59:59.000Z

168

On a class of inhomogeneous deformations of an incompressible Mooney-Rivlin solid  

E-Print Network [OSTI]

This work is devoted to the study of a specific inhomogeneous deformation in incompressible Mooney-Rivlin and neo-Hookean materials. The deformation under study is a case of "proportional stretch". Classes of models that can support special...

Ravindran, Parag

2001-01-01T23:59:59.000Z

169

On deformation twinning in a 17.5%Mn-TWIP steel: A physically...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

On deformation twinning in a 17.5%Mn-TWIP steel: A physically-based phenomenological model. On deformation twinning in a 17.5%Mn-TWIP steel: A physically-based phenomenological...

170

The Effect Of Viscoelastic Surfactants Used In Carbonate Matrix Acidizing On Wettability  

E-Print Network [OSTI]

Carbonate reservoirs are heterogeneous; therefore, proper acid placement/diversion is required to make matrix acid treatments effective. Viscoelastic surfactants (VES) are used as diverting agents in carbonate matrix acidizing. However...

Adejare, Oladapo

2012-07-16T23:59:59.000Z

171

Impact of Fe (III) on the Performance of Viscoelastic Surfactant-Based Acids  

E-Print Network [OSTI]

Viscoelastic surfactant (VES)-based acid systems have been used successfully in matrix and acid fracturing treatments. However, the existence of Fe (III) as a contaminant in such systems may lead to many problems, due to interactions between VES...

Shu, Yi

2013-08-02T23:59:59.000Z

172

Interfacial viscoelasticity, yielding and creep ringing of globular protein-surfactant mixtures  

E-Print Network [OSTI]

independent material proper- ties such as surface elasticity and viscosity1,2. The dynamic interfacial and pharmaceutical industry4,5. The interfacial viscoelasticity also plays an important role in spray coating

173

A Viscoelastic-Viscoplastic Analysis of Fiber Reinforced Polymer Composites Undergoing Mechanical Loading and Temperature Changes  

E-Print Network [OSTI]

This study presents a combined viscoelastic (VE)-viscoplastic (VP) analysis for Fiber Reinforced Polymer (FRP) composites subject to simultaneous mechanical load and conduction of heat. The studied FRP composites consist of unidirectional fibers...

Jeon, Jaehyeuk

2013-08-09T23:59:59.000Z

174

A Multi-scale Framework for Thermo-viscoelastic Analysis of Fiber Metal Laminates  

E-Print Network [OSTI]

Fiber Metal Laminates (FML) are hybrid composites with alternate layers of orthotropic fiber reinforced polymers (FRP) and isotropic metal alloys. FML can exhibit a nonlinear thermo-viscoelastic behavior under the influence of external mechanical...

Sawant, Sourabh P.

2010-01-14T23:59:59.000Z

175

Intrinsic Route to Melt Fracture in Polymer Extrusion: AWeakly Nonlinear Subcritical Instability of Viscoelastic Poiseuille Flow  

E-Print Network [OSTI]

Intrinsic Route to Melt Fracture in Polymer Extrusion: AWeakly Nonlinear Subcritical Instability generic route to melt fracture via a weakly nonlinear subcritical instability of viscoelastic Poiseuille ``subcritical'') instability due to normal stress effects; this instability appears to make melt fracture

van Saarloos, Wim

176

Pre-Stressed Viscoelastic Composites: Effective Incremental Moduli and Band-Gap Tuning  

SciTech Connect (OSTI)

We study viscoelastic wave propagation along pre-stressed nonlinear elastic composite bars. In the pre-stressed state we derive explicit forms for the effective incremental storage and loss moduli with dependence on the pre-stress. We also derive a dispersion relation for the effective wavenumber in the case of arbitrary frequency, hence permitting a study of viscoelastic band-gap tuning via pre-stress.

Parnell, William J. [School of Mathematics, Alan Turing Building, University of Manchester, Manchester, M13 9PL (United Kingdom)

2010-09-30T23:59:59.000Z

177

Seismology of plastic deformation Jero^me Weiss *, Francois Louchet  

E-Print Network [OSTI]

Seismology of plastic deformation Je´ro^me Weiss *, Franc¸ois Louchet Laboratoire de Glaciologie et-free critical picture of dislocational plasticity that challenges the classical continuum models of plasticity rights reserved. Keywords: Acoustic methods; Dislocation dynamics; Plastic deformation; Self

Weiss, Jérôme

178

Mesh Puppetry: Cascading Optimization of Mesh Deformation with Inverse Kinematics  

E-Print Network [OSTI]

approach builds upon traditional rigging by optimizing skeleton position and vertex weights. Keywords: Mesh deformation, nonlinear optimization, inverse kinematics, geometry processing. 1 Introduction,mathieu}@caltech.edu Figure 1: Armadillo Olympics: The Armadillo model (top left) can be deformed to take various sport poses

Zhou, Kun

179

${\\cal D}$-deformed harmonic oscillators  

E-Print Network [OSTI]

We analyze systematically several deformations arising from two-dimensional harmonic oscillators which can be described in terms of $\\cal{D}$-pseudo bosons. They all give rise to exactly solvable models, described by non self-adjoint hamiltonians whose eigenvalues and eigenvectors can be found adopting the quite general framework of the so-called $\\cal{D}$-pseudo bosons. In particular, we show that several models previously introduced in the literature perfectly fit into this scheme.

F. Bagarello; F. Gargano; D. Volpe

2014-12-30T23:59:59.000Z

180

Role of viscoelasticity and non-linear rheology in flows of complex fluids at high deformation rates  

E-Print Network [OSTI]

We combine pressure, velocimetry and birefringence measurements to study three phenomena for which the fluid rheology plays a dominant role: 1) shear banding in micellar fluids, 2) extension-dominated flows in microfluidic ...

Ober, Thomas J. (Thomas Joseph)

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Investigation of Deformation Dynamics in a Wrought Magnesium Alloy  

SciTech Connect (OSTI)

In the present research, the deformation dynamics and the effect of the deformation history on plastic deformation in a wrought magnesium alloy have been studied using real-time in-situ neutron diffraction measurements under a continuous loading condition and elastic-viscoplastic self-consistent (EVPSC) polycrystal modeling. The experimental results reveal that the pre-deformation delayed the activation of the tensile twinning during subsequent compression, mainly resulting from the residual strain. No apparent detwinning occurred during unloading and even in the elastic region during reverse loading. It is believed that the grain rotation played an important role in the elastic region during reverse loading. The EVPSC model, which has been recently updated by implementing the twinning and detwinning model, was employed to characterize the deformation mechanism during the strain-path changes. The simulation result predicts well the experimental observation from the real-time in-situ neutron diffraction measurements. The present study provides a deep insight of the nature of deformation mechanisms in a hexagonal close-packed structured polycrystalline wrought magnesium alloy, which might lead to a new era of deformation-mechanism research.

Wu, Wei [ORNL; Qiao, Hua [McMaster University; An, Ke [ORNL; Wu, Peidong [McMaster University; Liaw, Peter K [University of Tennessee, Knoxville (UTK)

2014-01-01T23:59:59.000Z

182

Motion of a Viscoelastic Micellar Fluid Around a Cylinder: Flow and Fracture  

E-Print Network [OSTI]

We present an experimental study of the motion of a viscoelastic micellar material around a moving cylinder, which ranges in response from fluid-like flow to solid-like tearing and fracture, depending on the cylinder radius and velocity. The observation of viscoelastic crack propagation driven by the cylinder indicates an extremely low tear strength, approximately equal to the steady state surface tension of the fluid. At the highest speeds a driven crack is observed in front of the cylinder, propagating with a fluctuating speed equal on average to the cylinder speed, here as low as 5% of the elastic wave speed in the medium.

Joseph R. Gladden; Andrew Belmonte

2006-05-25T23:59:59.000Z

183

Subcritical finite-amplitude solutions in plane Couette flow of visco-elastic fluids  

E-Print Network [OSTI]

Plane Couette flow of visco-elastic fluids is shown to exhibit a purely elastic subcritical instability in spite of being linearly stable. The mechanism of this instability is proposed and the nonlinear stability analysis of plane Couette flow of the Upper-Convected Maxwell fluid is presented. It is found that above the critical Weissenberg number, a small finite-size perturbation is sufficient to create a secondary flow, and the threshold value for the amplitude of the perturbation decreases as the Weissenberg number increases. The results suggest a scenario for weakly turbulent visco-elastic flow which is similar to the one for Newtonian fluids as a function of Reynolds number.

Alexander N. Morozov; Wim van Saarloos

2004-11-10T23:59:59.000Z

184

Variational Approach for Predicting the Load Deformation Response of a Double Stretched Membrane Reflector Module  

SciTech Connect (OSTI)

This report presents an analytical model useful for design and sizing purposes to describe the load deformation response of a stretched membrane reflector module structural system.

Murphy, L. M.

1985-10-01T23:59:59.000Z

185

q-deformed dynamics and Josephson junction  

E-Print Network [OSTI]

We define a generalized rate equation for an observable in quantum mechanics, that involves a parameter q and whose limit $q\\to 1$ gives the standard Heisenberg equation. The generalized rate equation is used to study dynamics of current biased Josephson junction. It is observed that this toy model incorporates diffraction like effects in the critical current. Physical interpretation for q is provided which is also shown to be q-deformation parameter.

Ramandeep S. Johal

2000-10-04T23:59:59.000Z

186

Role of deformation in exotic decay studies  

SciTech Connect (OSTI)

We have recently constructed a model for exotic decay studies using a cubic potential for the overlapping region that is smoothly connected by a Yukawa-plus-exponential potential for the region after separation. In this model, the zero-point vibration energy is explicitly used without violating the energy conservation and the inertial mass coefficient is made dependent on the center of mass distance, but the deformation effect has not been included. In this work, it is taken into account in both the parent and the daughter nuclei, keeping the emitted nucleus always spherical. This model is applied to the cases of {sup 14}C and {sup 24}Ne emissions and also for the recently reported cases of {sup 26}Ne, {sup 28,30}Mg, and {sup 34}Si emissions. It is found that the effect of the fragment deformation (which is always very small in the above decays) on lifetime is negligible while the parent deformation plays an appreciable role in the lifetime calculations.

Shanmugam, G.; Kamalaharan, B. (Department of Physics, Presidency College, Madras 600 005, India (IN))

1990-03-01T23:59:59.000Z

187

Cyclic performance of viscoelastic dielectric elastomers with solid hydrogel Yuanyuan Bai,1  

E-Print Network [OSTI]

of manufacturing or fabrication by 3D printing, silent operation, and capability of large deformation.1

Suo, Zhigang

188

Load capacity and rupture displacement in viscoelastic fiber bundles Theocharis Baxevanis1,  

E-Print Network [OSTI]

for this critical load is given. For stress levels below the critical value, the system suffers only partial failureLoad capacity and rupture displacement in viscoelastic fiber bundles Theocharis Baxevanis1 loading, assuming global load sharing GLS for the redistribution of load following fiber failure. We

Katsaounis, Theodoros D.

189

VISCOELASTIC BEHAVIOR OF POLYMER-THICKENED WATER-IN-OIL EMULSIONS  

E-Print Network [OSTI]

behavior of emulsions of water dispersed in a lubricant oil base and stabilized with a nonionic surfactantVISCOELASTIC BEHAVIOR OF POLYMER-THICKENED WATER-IN- OIL EMULSIONS MONTESI PE�A HIRASAKI PASQUALI concentration, emulsions with and without polyisobutylene (PIB, MW = 2.1 ± 0.2 x 106 Da) added to the oil phase

Natelson, Douglas

190

Peristaltic pumping of a viscoelastic fluid at high occlusion ratios and large Weissenberg numbers  

E-Print Network [OSTI]

Peristaltic pumping of a viscoelastic fluid at high occlusion ratios and large Weissenberg numbers pumping is a mechanism for transporting fluid or immersed par- ticles in a channel by waves of contraction- vestigate numerically the peristaltic pumping of an incompressible viscoelas- tic fluid using the simple

Bigelow, Stephen

191

Peristaltic pumping and irreversibility of a Stokesian viscoelastic fluid Joseph Teran,1  

E-Print Network [OSTI]

Peristaltic pumping and irreversibility of a Stokesian viscoelastic fluid Joseph Teran,1 Lisa Fauci, USA Received 28 January 2008; accepted 1 July 2008; published online 28 July 2008 Peristaltic pumping in the esophagus, intestine, oviduct, and ureter. While peristaltic pumping of a Newtonian fluid is well understood

Shelley, Michael

192

Viscoelastic Behavior of Poly(ether imide) Incorporated with Multiwalled Carbon Nanotubes  

E-Print Network [OSTI]

plastic, and suitable for use in many demanding applications because of its relatively high strength, high, and thermal properties of engineering plastics, including poly(ether imide) (PEI), with various nanoin; viscoelastic properties INTRODUCTION The demand for lightweight materials with high strength and thermal

Fisher, Frank

193

Normal Stresses and Interface Displacement: Influence of Viscoelasticity on Enhanced Oil  

E-Print Network [OSTI]

Normal Stresses and Interface Displacement: Influence of Viscoelasticity on Enhanced Oil Recovery assistée -- Une des méthodes de récupération assistée du pétrole (EOR - Enhanced Oil Recovery) consiste à Recovery Efficiency -- One of chemical Enhanced Oil Recovery (EOR) methods consists in injecting aqueous

Paris-Sud XI, Université de

194

The viscoelastic behaviour of raw and anaerobic digested sludge: strong similarities with soft-glassy materials  

E-Print Network [OSTI]

1 The viscoelastic behaviour of raw and anaerobic digested sludge: strong similarities with soft confronted with a dramatically increasing flow of sewage sludge. To improve treatment efficiency, process reliable flow properties to simulate the process, this work is an attempt to approach sludge rheological

Paris-Sud XI, Université de

195

SUBCRITICAL INSTABILITIES IN PLANE COUETTE FLOW OF VISCO-ELASTIC FLUIDS  

E-Print Network [OSTI]

SUBCRITICAL INSTABILITIES IN PLANE COUETTE FLOW OF VISCO-ELASTIC FLUIDS Alexander N. Morozov of an eigenfunction of the linearized equations of motion becomes subcritically unstable, and the threshold value, subcritical instabilities, amplitude equation Introduction In the last decades, stability of flows of polymers

van Saarloos, Wim

196

Formation of beads-on-a-string structures during break-up of viscoelastic filaments  

E-Print Network [OSTI]

Break-up of viscoelastic filaments is pervasive in both nature and technology. If a filament is formed by placing a drop of saliva between a thumb and forefinger and is stretched, the filament’s morphology close to break-up ...

Bhat, Pardeep P.

197

The effect of confinement on the deformation of microfluidic drops  

E-Print Network [OSTI]

We study the deformation of drops squeezed between the floor and ceiling of a microchannel and subjected to a hyperbolic flow. We observe that the maximum deformation of drops depends on both the drop size and the rate of strain of the external flow and can be described with power laws with exponents 2.59 +/- 0.28 and 0.94 +/- 0.04 respectively. We develop a theoretical model to describe the deformation of squeezed drops based on the Darcy approximation for shallow geometries and the use of complex potentials. The model describes the steady-state deformation of the drops as a function of a non-dimensional parameter Ca d^2, where Ca is the capillary number (proportional to the strain rate and the drop size) and d is a confinement parameter equal to the drop size divided by the channel height. For small deformations, the theoretical model predicts a linear relationship between the deformation of drops and this parameter, in good agreement with the experimental observations.

Ulloa, Camilo; Cordero, María Luisa

2013-01-01T23:59:59.000Z

198

Thermomechanical characterization of a membrane deformable mirror  

SciTech Connect (OSTI)

A membrane deformable mirror has been investigated for its potential use in high-energy laser systems. Experiments were performed in which the deformable mirror was heated with a 1 kW incandescent lamp and the thermal profile, the wavefront aberrations, and the mechanical displacement of the membrane were measured. A finite element model was also developed. The wavefront characterization experiments showed that the wavefront degraded with heating. Above a temperature of 35 deg. C, the wavefront characterization experiments indicated a dramatic increase in the high-order wavefront modes before the optical beam became immeasurable in the sensors. The mechanical displacement data of the membrane mirror showed that during heating, the membrane initially deflected towards the heat source and then deflected away from the heat source. Finite element analysis (FEA) predicted a similar displacement behavior as shown by the mechanical displacement data but over a shorter time scale and a larger magnitude. The mechanical displacement data also showed that the magnitude of membrane displacement increased with the experiments that involved higher temperatures. Above a temperature of 35 deg. C, the displacement data showed that random deflections as a function of time developed and that the magnitude of these deflections increased with increased temperature. We concluded that convection, not captured in the FEA, likely played a dominant role in mirror deformation at temperatures above 35 deg. C.

Morse, Kathleen A.; McHugh, Stuart L.; Fixler, Jeff

2008-10-10T23:59:59.000Z

199

A study of a flapping flag in viscoelastic fluids and its implications for micro-scale swimming in biofluids  

E-Print Network [OSTI]

Biological cells and organisms employ a different method of propulsion when in viscous, viscolelastic fluids rather than Newtonian fluids. By studying the dynamics of a flag under a flow of a viscoelastic fluid, we hope ...

Fellman, Batya A. (Batya Ayala)

2008-01-01T23:59:59.000Z

200

Experimental Studies on Visco-plastic Lubrication of Visco-elastic Fluid: Interfacial Instability and Geometry Effect  

E-Print Network [OSTI]

of application in industry, such as in co- extrusion processes and lubricated pipelining. In the case of a duct to establish the base multi-layer flows at all, using a visco-elastic fluid (Poly Ethylene Oxide solution

Ishii, Hitoshi

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

A large-deformation thermo-mechanically coupled elastic-viscoplastic theory for amorphous polymers : modeling of micro-scale forming and the shape memory phenomenon  

E-Print Network [OSTI]

Amorphous polymers are important engineering materials; however, their nonlinear, strongly temperature- and rate-dependent elastic-viscoplastic behavior is still not very well understood, and is modeled by existing ...

Srivastava, Vikas

2010-01-01T23:59:59.000Z

202

Quadrupolar correlations and deformation effects on nuclear transition matrix elements of double-{beta} decay  

SciTech Connect (OSTI)

The effect of quadrupolar correlations vis-a-vis deformation on the nuclear transition matrix elements of two neutrino and neutrinoless {beta}{beta} decay is studied in the PHFB model. It is observed that the deformation effects scale almost similarly for both the two neutrino and neutrinoless {beta}{beta} decay modes and the independent deformations of initial and final nuclei are important parameters to describe the nuclear transition matrix elements for different modes of {beta}{beta} decay.

Rath, P. K. [Department of Physics, University of Lucknow, Lucknow-226007 (India)

2009-11-09T23:59:59.000Z

203

A stable and convergent scheme for viscoelastic flow in contraction channels  

SciTech Connect (OSTI)

We present a new algorithm to simulate unsteady viscoelastic flows in abrupt contraction channels. In our approach we split the viscoelastic terms of the Oldroyd-B constitutive equation using Duhamel's formula and discretize the resulting PDEs using a semi-implicit finite difference method based on a Lax-Wendroff method for hyperbolic terms. In particular, we leave a small residual elastic term in the viscous limit by design to make the hyperbolic piece well-posed. A projection method is used to impose the incompressibility constraint. We are able to compute the full range of elastic flows in an abrupt contraction channel--from the viscous limit to the elastic limit--in a stable and convergent manner for elastic Mach numbers less than one. We demonstrate the method for unsteady Oldroyd-B and Maxwell fluids in planar contraction channels.

Trebotich, David; Colella, Phillip; Miller, Gregory

2004-02-15T23:59:59.000Z

204

The viscoelastic properties of chromatin and the nucleoplasm revealed by scale-dependent protein mobility  

E-Print Network [OSTI]

The eukaryotic cell nucleus harbors the DNA genome that is organized in a dynamic chromatin network and embedded in a viscous crowded fluid. This environment directly affects enzymatic reactions and target search processes that access the DNA sequence information. However, its physical properties as a reaction medium are poorly understood. Here, we exploit mobility measurements of differently sized inert green fluorescent tracer proteins to characterize the viscoelastic properties of the nuclear interior of a living human cell. We find that it resembles a viscous fluid on small and large scales, but appears viscoelastic on intermediate scales that change with protein size. Our results are consistent with simulations of diffusion through polymers and suggest that chromatin forms a random obstacle network rather than a self-similar structure with fixed fractal dimension. By calculating how long molecules remember their previous position in dependence on their size, we evaluate how the nuclear environment affects search processes of chromatin targets.

Fabian Erdel; Michael Baum; Karsten Rippe

2014-09-23T23:59:59.000Z

205

TO APPEAR IN THE PROCEEDINGS OF THE IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION (ICRA), 2011. Modeling and Perception of Deformable One-Dimensional Objects  

E-Print Network [OSTI]

the simulation, perception, and manipulation of such objects. An important application of these tasks lies that are highly dependent on material properties. This paper proposes an approach for fitting simulation models-rigid objects like thread, rope, hair, and plants in real world settings is a challenging task. These objects

Abbeel, Pieter

206

Modeling and Perception of Deformable One-Dimensional Objects Shervin Javdani, Sameep Tandon, Jie Tang, James F. O'Brien, Pieter Abbeel  

E-Print Network [OSTI]

the simulation, perception, and manipulation of such objects. An important application of these tasks lies that are highly dependent on material properties. This paper proposes an approach for fitting simulation models-rigid objects like thread, rope, hair, and plants in real world settings is a challenging task. These objects

O'Brien, James F.

207

Analysis on q-deformed quantum spaces  

E-Print Network [OSTI]

A q-deformed version of classical analysis is given to quantum spaces of physical importance, i.e. Manin plane, q-deformed Euclidean space in three or four dimensions, and q-deformed Minkowski space. The subject is presented in a rather complete and selfcontained way. All relevant notions are introduced and explained in detail. The different possibilities to realize the objects of q-deformed analysis are discussed and their elementary properties are studied. In this manner attention is focused on star products, q-deformed tensor products, q-deformed translations, q-deformed partial derivatives, dual pairings, q-deformed exponentials, and q-deformed integration. The main concern of this work is to show that these objects fit together in a consistent framework, which is suitable to formulate physical theories on quantum spaces.

Hartmut Wachter

2006-04-13T23:59:59.000Z

208

Deforming nanocrystalline nickel at ultrahigh strain rates Y. M. Wang,a  

E-Print Network [OSTI]

Deforming nanocrystalline nickel at ultrahigh strain rates Y. M. Wang,a E. M. Bringa, J. M. Mc of this letter is to investigate these deformation mechanisms using a model material, nanocrystalline nickel Goodfellow Inc.; and 2 we also electrodeposited Ni samples at several other grain sizes, 30­100 nm.11

Meyers, Marc A.

209

Low fault friction in Iran implies localized deformation for the ArabiaEurasia collision zone  

E-Print Network [OSTI]

Low fault friction in Iran implies localized deformation for the Arabia­Eurasia collision zone P velocity field of the present-day deformation in Iran is modeled using a 3-dimensional (3D) finite element of the kinematics in Iran, but the complex velocity field of the surrounding South Caspian basin cannot be fitted

Vernant, Philippe

210

WAVE-SOLID INTERACTIONS IN SHOCK INDUCED DEFORMATION PROCESSES Paper #1003  

E-Print Network [OSTI]

pressure created by the shock wave is above the dynamic yield stress (Hugonoit Elastic Limit, HEL) of metalWAVE-SOLID INTERACTIONS IN SHOCK INDUCED DEFORMATION PROCESSES Paper #1003 Yajun Fan, Youneng Wang 10027, USA Abstract A model was developed for material deformation processes induced by laser generated

Yao, Y. Lawrence

211

Microstructurally-based constitutive models of cytoskeletal networks for simulation of the biomechanical response of biological cells  

E-Print Network [OSTI]

The elastic and viscoelastic stress-strain behavior of cytoskeletal networks, important to many cellular functions, is modeled via a microstructurally-informed continuum mechanics approach. The force-extension behavior of ...

Palmer, Jeffrey Shane

2008-01-01T23:59:59.000Z

212

Modeling and Algorithmic Approaches to Constitutively-Complex, Micro-structured Fluids  

SciTech Connect (OSTI)

The team for this Project made significant progress on modeling and algorithmic approaches to hydrodynamics of fluids with complex microstructure. Our advances are broken down into modeling and algorithmic approaches. In experiments a driven magnetic bead in a complex fluid accelerates out of the Stokes regime and settles into another apparent linear response regime. The modeling explains the take-off as a deformation of entanglements, and the longtime behavior is a nonlinear, far-from-equilibrium property. Furthermore, the model has predictive value, as we can tune microstructural properties relative to the magnetic force applied to the bead to exhibit all possible behaviors. Wave-theoretic probes of complex fluids have been extended in two significant directions, to small volumes and the nonlinear regime. Heterogeneous stress and strain features that lie beyond experimental capability were studied. It was shown that nonlinear penetration of boundary stress in confined viscoelastic fluids is not monotone, indicating the possibility of interlacing layers of linear and nonlinear behavior, and thus layers of variable viscosity. Models, algorithms, and codes were developed and simulations performed leading to phase diagrams of nanorod dispersion hydrodynamics in parallel shear cells and confined cavities representative of film and membrane processing conditions. Hydrodynamic codes for polymeric fluids are extended to include coupling between microscopic and macroscopic models, and to the strongly nonlinear regime.

Forest, Mark Gregory [University of North Carolina at Chapel Hill] [University of North Carolina at Chapel Hill

2014-05-06T23:59:59.000Z

213

Cylindric Macdonald functions and a deformation of the Verlinde algebra  

E-Print Network [OSTI]

Cylindric Macdonald functions and a deformation of the Verlinde algebra Christian Korff (christian arxiv: 1110.6356 December 6, 2011 Christian Korff Cylindric Macdonald functions #12;Outline 1 q-Heisenberg algebra and exactly solvable lattice models 2 partition functions: cylindric Macdonald functions 3

Guo, Zaoyang

214

Conformal Deformation from Normal to Hermitian Random Matrix Ensembles  

E-Print Network [OSTI]

We investigate the eigenvalues statistics of ensembles of normal random matrices when their order N tends to infinite. In the model the eigenvalues have uniform density within a region determined by a simple analytic polynomial curve. We study the conformal deformations of normal random ensembles to Hermitian random ensembles and give sufficient conditions for the latter to be a Wigner ensemble.

Alexei M. Veneziani; Tiago Pereira; Domingos H. U. Marchetti

2009-09-04T23:59:59.000Z

215

Quantum mechanical effects from deformation theory  

SciTech Connect (OSTI)

We consider deformations of quantum mechanical operators by using the novel construction tool of warped convolutions. The deformation enables us to obtain several quantum mechanical effects where electromagnetic and gravitomagnetic fields play a role. Furthermore, a quantum plane can be defined by using the deformation techniques. This in turn gives an experimentally verifiable effect.

Much, A. [Max-Planck-Institute for Mathematics in the Sciences, 04103 Leipzig, Germany and Institute for Theoretical Physics, University of Leipzig, 04009 Leipzig (Germany)] [Max-Planck-Institute for Mathematics in the Sciences, 04103 Leipzig, Germany and Institute for Theoretical Physics, University of Leipzig, 04009 Leipzig (Germany)

2014-02-15T23:59:59.000Z

216

CubeSat deformable mirror demonstration  

E-Print Network [OSTI]

The goal of the CubeSat Deformable Mirror Demonstration (DeMi) is to characterize the performance of a small deformable mirror over a year in low-Earth orbit. Small form factor deformable mirrors are a key technology needed ...

Cahoy, Kerri

217

A non-linear elastic constitutive framework for replicating plastic deformation in solids.  

SciTech Connect (OSTI)

Ductile metals and other materials typically deform plastically under large applied loads; a behavior most often modeled using plastic deformation constitutive models. However, it is possible to capture some of the key behaviors of plastic deformation using only the framework for nonlinear elastic mechanics. In this paper, we develop a phenomenological, hysteretic, nonlinear elastic constitutive model that captures many of the features expected of a plastic deformation model. This model is based on calculating a secant modulus directly from a material's stress-strain curve. Scalar stress and strain values are obtained in three dimensions by using the von Mises invariants. Hysteresis is incorporated by tracking an additional history variable and assuming an elastic unloading response. This model is demonstrated in both single- and multi-element simulations under varying strain conditions.

Roberts, Scott Alan; Schunk, Peter Randall

2014-02-01T23:59:59.000Z

218

A coordinate-dependent superspace deformation from string theory  

E-Print Network [OSTI]

Starting from a type II superstring model defined on $R^{2,2}\\times CY_6$ in a linear graviphoton background, we derive a coordinate dependent $C$-deformed ${\\cal N}=1$, $d=2+2$ superspace. The chiral fermionic coordinates $\\theta$ satisfy a Clifford algebra, while the other coordinate algebra remains unchanged. We find a linear relation between the graviphoton field strength and the deformation parameter. The null coordinate dependence of the graviphoton background allows to extend the results to all orders in $\\alpha'$.

L. G. Aldrovandi; F. A. Schaposnik; G. A. Silva

2006-03-08T23:59:59.000Z

219

The viscoelastic properties of linear-star blends  

E-Print Network [OSTI]

In order to understand the nature of polydispersity and characterize the effect of branching architecture, the model blend of linear and star polymer, which is the simplest branched polymer, is contrived. In this blend system, chain dynamics...

Lee, Jung Hun

2000-01-01T23:59:59.000Z

220

Strain Heterogeneity and Damage Nucleation at Grain Boundaries during Monotonic Deformation in Commercial Purity Titanium  

SciTech Connect (OSTI)

Heteroeneous strain was analyzed in polycrystalline, commercial-purity titanium using many experimental techniques that provide information about microstructure, dislocation arrangement, grain orientation, orientation gradients, surface topography, and local strain gradients. The recrystallized microstructure with 50-200 ?m grains was extensively characterized before and after deformation using 4-point bending to strains between 2% and 15%. Extremely heterogeneous deformation occurred along some grain boundaries, leading to orientation gradients exceeding 10{sup o} over 10-20 {micro}m. Patches of highly characterized microstructure were modeled using crystal plasticity finite element (CPFE) analysis to simulate the deformation to evaluate the ability of the CPFE model to capture local deformation processes. Damage nucleation events were identified that are associated with twin interactions with grain boundaries. Progress toward identifying fracture initiation criteria based upon slip and twin interactions with grain boundaries is illustrated with related CPFE simulations of deformation in a TiAl alloy.

Bieler, T. R. [Michigan State University, East Lansing; Crimp, M. A. [Michigan State University, East Lansing; Yang, Y. [Michigan State University, East Lansing; Eisenlohr, P. [Max-Planck-Institut fur Eisenforschung, Germany; Mason, D. E. [Albion College; Liu, W. [Argonne National Laboratory (ANL); Ice, Gene E [ORNL

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Accounting for inertia effects to access the high-frequency microrheology of viscoelastic fluids  

E-Print Network [OSTI]

We study the Brownian motion of microbeads immersed in water and in a viscoelastic wormlike micelles solution by optical trapping interferometry and diffusing wave spectroscopy. Through the mean-square displacement obtained from both techniques, we deduce the mechanical properties of the fluids at high frequencies by explicitly accounting for inertia effects of the particle and the surrounding fluid at short time scales. For wormlike micelle solutions, we recover the 3/4 scaling exponent for the loss modulus over two decades in frequency as predicted by the theory for semiflexible polymers.

P. Domínguez-García; Frédéric Cardinaux; Elena Bertseva; László Forró; Frank Scheffold; Sylvia Jeney

2014-12-03T23:59:59.000Z

222

Viscoelastic modes in a strongly coupled, cold, magnetized dusty plasma  

SciTech Connect (OSTI)

A generalized hydrodynamical model has been used to study the low frequency modes in a strongly coupled, cold, magnetized dusty plasma. Such plasmas exhibit elastic properties due to the strong correlations among dust particles and the tensile stresses imparted by the magnetic field. It has been shown that longitudinal compressional Alfven modes and elasticity modified transverse shear mode exist in such a medium. The features of these collective modes are established and discussed.

Banerjee, Debabrata; Mylavarapu, Janaki Sita; Chakrabarti, Nikhil [Saha Institute of Nuclear Physics, I/AF Bidhannagar, Calcutta 700 064 (India)

2010-11-15T23:59:59.000Z

223

Volume 0 (1981), Number 0 pp. 17 COMPUTER GRAPHICS forum Resampling Strategies for Deforming MLS Surfaces  

E-Print Network [OSTI]

Volume 0 (1981), Number 0 pp. 1­7 COMPUTER GRAPHICS forum Resampling Strategies for Deforming MLS Graphics]: Computational Geometry and Object Modeling G.1.2 [Numerical Analysis]: Approximation G.2

Buscaglia, Gustavo C.

224

Quantum limits to estimation of photon deformation  

E-Print Network [OSTI]

We address potential deviations of radiation field from the bosonic behaviour and employ local quantum estimation theory to evaluate the ultimate bounds to precision in the estimation of these deviations using quantum-limited measurements on optical signals. We consider different classes of boson deformation and found that intensity measurement on coherent or thermal states would be suitable for their detection making, at least in principle, tests of boson deformation feasible with current quantum optical technology. On the other hand, we found that the quantum signal-to-noise ratio (QSNR) is vanishing with the deformation itself for all the considered classes of deformations and probe signals, thus making any estimation procedure of photon deformation inherently inefficient. A partial way out is provided by the polynomial dependence of the QSNR on the average number of photon, which suggests that, in principle, it would be possible to detect deformation by intensity measurements on high-energy thermal states.

Giovanni De Cillis; Matteo G. A. Paris

2014-07-08T23:59:59.000Z

225

On the postglacial isostatic adjustment of the British Isles and the shallow viscoelastic structure of the Earth  

E-Print Network [OSTI]

of the Earth W. R. Peltier,1 I. Shennan,2 R. Drummond1 and B. Horton2 1 Department of Physics, University viscoelastic theory of the glacial isostatic adjustment (GIA) process, most recently reviewed in Peltier (1998a on the inverse problem for mantle viscosity (see the papers by Peltier 1998b and Wieczerkowski et al. 1999

Peltier, W. Richard

226

Subcritical Finite-Amplitude Solutions for Plane Couette Flow of Viscoelastic Fluids Alexander N. Morozov and Wim van Saarloos  

E-Print Network [OSTI]

Subcritical Finite-Amplitude Solutions for Plane Couette Flow of Viscoelastic Fluids Alexander N is shown to exhibit a purely elastic subcritical instability at a very small-Reynolds number in spite. In this Letter we show that visco- elastic plane Couette flow (PCF) exhibits a subcritical instability to finite

van Saarloos, Wim

227

Geomechanical Development of Fractured Reservoirs During Gas Production  

E-Print Network [OSTI]

is constructed by implementing a poroviscoelastic model into the dual permeability (DPM)-finite element model (FEM) to investigate the coupled time-dependent viscoelastic deformation, fracture network evolution and compressible fluid flow in gas shale reservoir...

Huang, Jian

2013-04-05T23:59:59.000Z

228

Origami-enabled deformable silicon solar cells  

SciTech Connect (OSTI)

Deformable electronics have found various applications and elastomeric materials have been widely used to reach flexibility and stretchability. In this Letter, we report an alternative approach to enable deformability through origami. In this approach, the deformability is achieved through folding and unfolding at the creases while the functional devices do not experience strain. We have demonstrated an example of origami-enabled silicon solar cells and showed that this solar cell can reach up to 644% areal compactness while maintaining reasonable good performance upon cyclic folding/unfolding. This approach opens an alternative direction of producing flexible, stretchable, and deformable electronics.

Tang, Rui; Huang, Hai; Liang, Hanshuang; Liang, Mengbing [School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287 (United States); Tu, Hongen; Xu, Yong [Electrical and Computer Engineering, Wayne State University, 5050 Anthony Wayne Dr., Detroit, Michigan 48202 (United States); Song, Zeming; Jiang, Hanqing, E-mail: hanqing.jiang@asu.edu [School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287 (United States); Yu, Hongyu, E-mail: hongyu.yu@asu.edu [School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287 (United States); School of Earth and Space Exploration, Arizona State University, Tempe, Arizona 85287 (United States)

2014-02-24T23:59:59.000Z

229

2012 ROCK DEFORMATION: FEEDBACK PROCESSES IN ROCK DEFORMATION GORDON RESEARCH CONFERENCE, AUGUST 19-24, 2012  

SciTech Connect (OSTI)

Topics covered include: Failure At High Confining Pressure; Fluid-assisted Slip, Earthquakes & Fracture; Reaction-driven Cracking; Fluid Transport, Deformation And Reaction; Localized Fluid Transport And Deformation; Earthquake Mechanisms; Subduction Zone Dynamics And Crustal Growth.

Kelemen, Peter

2012-08-24T23:59:59.000Z

230

Influence of shockwave obliquity on deformation twin formation in Ta  

SciTech Connect (OSTI)

Energetic loading subjects a material to a 'Taylor wave' (triangular wave) loading profile that experiences an evolving balance of hydrostatic (spherical) and deviatoric stresses. While much has been learned over the past five decades concerning the propensity of deformation twinning in samples shockloaded using 'square-topped' profiles as a function of peak stress, achieved most commonly via flyer plate loading, less is known concerning twinning propensity during non-I-dimensional sweeping detonation wave loading. Systematic small-scale energetically-driven shock loading experiments were conducted on Ta samples shock loaded with PEFN that was edge detonated. Deformation twinning was quantified in post-mortem samples as a function of detonation geometry and radial position. In the edge detonated loading geometry examined in this paper, the average volume fraction of deformation twins was observed to drastically increase with increasing shock obliquity. The results of this study are discussed in light of the formation mechanisms of deformation twins, previous literature studies of twinning in shocked materials, and modeling of the effects of shock obliquity on the evolution of the stress tensor during shock loading.

Gray, George T., III [Los Alamos National Laboratory; Livescu, V [Los Alamos National Laboratory; Cerreta, E K [Los Alamos National Laboratory; Mason, T A [Los Alamos National Laboratory; Maudlin, P J [RETIRED; Bingert, J F [Los Alamos National Laboratory

2009-02-18T23:59:59.000Z

231

FEM Analysis ofFEM Analysis of Deformation and Fracture ofDeformation and Fracture of  

E-Print Network [OSTI]

FEM Analysis ofFEM Analysis of Deformation and Fracture ofDeformation and Fracture of Deformation and Fracture in Polycrystalline -TiAl + 2-Ti3Al Single Crystals #12;Use of -TiAl + 2-Ti3Al Alloys-Temperature Ductility ·Low Ambient-Temperature Fracture Toughness (KIC

Grujicic, Mica

232

Thermally driven visco-elastic measurement technique via spectral variations in scanning probe microscopy cantilevers  

E-Print Network [OSTI]

Understanding how fluids respond to various deformations is of great importance to a spectrum of disciplines ranging from bio-medical research on joint replacements to sealing technology in industrial machinery. Specifically, ...

Jones, Ryan Edward, 1974-

2004-01-01T23:59:59.000Z

233

Multitrace deformation of the Aharony-Bergman-Jafferis-Maldacena theory  

SciTech Connect (OSTI)

Motivated by the study of big crunch singularities in asymptotically AdS{sub 4} space-times, we consider a marginal triple trace deformation of Aharony-Bergman-Jafferis-Maldacena (ABJM) theory. The deformation corresponds to adding a potential which is unbounded below. In a 't Hooft large N limit, the beta function for the triple trace deformation vanishes, which is consistent with the near-boundary behavior of the bulk fields. At the next order in the 1/N expansion, the triple trace couplings exhibit nontrivial running, which we analyze explicitly in the limit of zero 't Hooft coupling, in which the model reduces to an O(N)xO(N) vector model with large N. In this limit, we establish the existence of a perturbative UV fixed point, and we comment on possible nonperturbative effects. We also show that the bulk analysis leading to big crunch singularities extends to the Z{sub k} orbifold models dual to ABJM theory.

Craps, Ben [Theoretische Natuurkunde, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels (Belgium); International Solvay Institutes, Boulevard du Triomphe, ULB-C.P.231, B-1050 Brussels (Belgium); Hertog, Thomas [International Solvay Institutes, Boulevard du Triomphe, ULB-C.P.231, B-1050 Brussels (Belgium); APC, Universite Paris 7, 10 rue A.Domon et L.Duquet, 75205 Paris (France); Turok, Neil [Perimeter Institute for Theoretical Physics, 31 Caroline Street N, Waterloo, Ontario N2L2Y5, Canada, and DAMTP, CMS, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)

2009-10-15T23:59:59.000Z

234

On beta-deformations and Noncommutativity  

E-Print Network [OSTI]

We elucidate the connection between the N=1 beta-deformed SYM theory and noncommutativity. Our starting point is the T-duality generating transformation involved in constructing the gravity duals of both beta-deformed and noncommutative gauge theories. We show that the two methods can be identified provided that a particular submatrix of the O(3,3,R) group element employed in the former case, is interpreted as the noncommutativity parameter associated with the deformation of the transverse space. It is then explained how to construct the matrix in question, relying solely on information extracted from the gauge theory Lagrangian and basic notions of AdS/CFT. This result may provide an additional tool in exploring deformations of the N=4 SYM theory. Finally we use the uncovered relationship between beta-deformations and noncommutativity to find the gravity background dual to a noncommutative gauge theory with beta-type noncommutativity parameter.

Manuela Kulaxizi

2006-10-30T23:59:59.000Z

235

Clustering and Triaxial Deformations of $^{40}$Ca  

E-Print Network [OSTI]

We have studied the positive-parity states of $^{40}$Ca using antisymmetrized molecular dynamics (AMD) and the generator coordinate method (GCM). Imposing two different kinds of constraints on the variational calculation, we have found various kinds of $^{40}{\\rm Ca}$ structures such as a deformed-shell structure, as well as $\\alpha$-$^{36}$Ar and $^{12}$C-$^{28}$Si cluster structures. After the GCM calculation, we obtained a normal-deformed band and a superdeformed band together with their side bands associated with triaxial deformation. The calculated $B(E2)$ values agreed well with empirical data. It was also found that the normal-deformed and superdeformed bands have a non-negligible $\\alpha$-$^{36}$Ar cluster component and $^{12}$C-$^{28}$Si cluster component, respectively. This leads to the presence of an $\\alpha$-$^{36}$Ar higher-nodal band occurring above the normal-deformed band.

Yasutaka Taniguchi; Masaaki Kimura; Yoshiko Kanada-En'yo; Hisashi Horiuchi

2007-07-05T23:59:59.000Z

236

Studies of the viscoelastic properties of water confined between surfaces of specified chemical nature.  

SciTech Connect (OSTI)

This report summarizes the work completed under the Laboratory Directed Research and Development (LDRD) project 10-0973 of the same title. Understanding the molecular origin of the no-slip boundary condition remains vitally important for understanding molecular transport in biological, environmental and energy-related processes, with broad technological implications. Moreover, the viscoelastic properties of fluids in nanoconfinement or near surfaces are not well-understood. We have critically reviewed progress in this area, evaluated key experimental and theoretical methods, and made unique and important discoveries addressing these and related scientific questions. Thematically, the discoveries include insight into the orientation of water molecules on metal surfaces, the premelting of ice, the nucleation of water and alcohol vapors between surface asperities and the lubricity of these molecules when confined inside nanopores, the influence of water nucleation on adhesion to salts and silicates, and the growth and superplasticity of NaCl nanowires.

Houston, Jack E.; Grest, Gary Stephen; Moore, Nathan W.; Feibelman, Peter J.

2010-09-01T23:59:59.000Z

237

1Plastic deformation and fracture processes in metallic and ceramic nanomaterials... 2007 Advanced Study Center Co. Ltd.  

E-Print Network [OSTI]

1Plastic deformation and fracture processes in metallic and ceramic nanomaterials... © 2007-mail: ovidko@def.ipme.ru PLASTIC DEFORMATION AND FRACTURE PROCESSES IN METALLIC AND CERAMIC NANOMATERIALS at the boundaries between the large grains and nanoscale matrix. In the framework of the model, cracks are generated

Ovid'ko Ilya A.

238

To mechanics of deformation, flow, and fracture  

E-Print Network [OSTI]

It is stated in the main in essence new approach to mechanics of the stressed state of the solid body from statistically isotropic material and the homogeneous liquid dynamics. The approach essence is in the detected property of the core-shell spontaneous structurization of internal energy of the solid and liquid bodies in its natural state and under action of external forces. The method elements of construction of physically adequate model of the stressed state of the solid and liquid bodies, reproduced exactly its behavior on the stages of elastic and plastic deformation, flow and fracture, are stated. It is adduced a number of the examples of the stressed state construction of the simple form bodies under action of its tension, compression, torsion and at its contact interaction. For the first time it is adduced structure of the principal - normal - stresses in cylindrical bar under action of the torsion moment. The detected property and the developed method is one of necessary bases for construction of physically adequate mathematical model of the stressed state of the body and fluid in contrast to traditional approach.

S. L. Arsenjev

2008-09-23T23:59:59.000Z

239

Minor Groove Deformability of DNA: A Molecular Dynamics Free...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Minor Groove Deformability of DNA: A Molecular Dynamics Free EnergySimulation Study. Minor Groove Deformability of DNA: A Molecular Dynamics Free EnergySimulation Study. Abstract:...

240

Steady state deformation of the Coso Range, east central California...  

Open Energy Info (EERE)

from satellite radar interferometry Abstract Observations of deformation from 1992 to 1997 in the southern Coso Range using satellite radar interferometry show deformation rates...

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Surface Slope Metrology on Deformable Soft X-ray Mirrors  

SciTech Connect (OSTI)

We report on the current state of surface slope metrology on deformable mirrors for soft x-rays at the Advanced Light Source (ALS). While we are developing techniques for in situ at-wavelength tuning, we are refining methods of ex situvisible-light optical metrology to achieve sub-100-nrad accuracy. This paper reports on laboratory studies, measurements and tuning of a deformable test-KB mirror prior to its use. The test mirror was bent to a much different optical configuration than its original design, achieving a 0.38 micro-radian residual slope error. Modeling shows that in some cases, by including the image conjugate distance as an additional free parameter in the alignment, along with the two force couples, fourth-order tangential shape errors (the so-called bird shape) can be reduced or eliminated.

Yuan, S.; Yashchuk, V.V.; Goldberg, K.A.; Celestre, R.; Church, M.; McKinney, W.R.; Morrison, G.; Warwick, T.

2009-09-18T23:59:59.000Z

242

Surface Slope Metrology on Deformable Soft X-ray Mirrors  

SciTech Connect (OSTI)

We report on the current state of surface slope metrology on deformable mirrors for soft x-rays at the Advanced Light Source (ALS). While we are developing techniques for in situ at-wavelength tuning, we are refining methods of ex situ visible-light optical metrology to achieve sub-100-nrad accuracy. This paper reports on laboratory studies, measurements and tuning of a deformable test-KB mirror prior to its use. The test mirror was bent to a much different optical configuration than its original design, achieving a 0.38 micro-radian residual slope error. Modeling shows that in some cases, by including the image conjugate distance as an additional free parameter in the alignment, along with the two force couples, fourth-order tangential shape errors (the so-called bird shape) can be reduced or eliminated.

Yuan, Sheng; Yashchuk, Valeriy V.; Goldberg, Kenneth A.; Celestre, Rich; Church, Matthew; McKinney, Wayne R.; Morrison, Greg; Warwick, Tony

2010-01-31T23:59:59.000Z

243

Surface Slope Metrology on Deformable Soft X-ray Mirrors  

SciTech Connect (OSTI)

We report on the current state of surface slope metrology on deformable mirrors for soft x-rays at the Advanced Light Source (ALS). While we are developing techniques for in situ at-wavelength tuning, we are refining methods of ex situ visible-light optical metrology to achieve sub-100-nrad accuracy. This paper reports on laboratory studies, measurements and tuning of a deformable test-KB mirror prior to its use. The test mirror was bent to a much different optical configuration than its original design, achieving a 0.38 micro-radian residual slope error. Modeling shows that in some cases, by including the image conjugate distance as an additional free parameter in the alignment, along with the two force couples, fourth-order tangential shape errors (the so-called bird shape) can be reduced or eliminated.

Yuan Sheng; Yashchuk, Valeriy V.; Celestre, Rich; Church, Matthew; McKinney, Wayne R.; Morrison, Greg; Warwick, Tony [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Goldberg, Kenneth A. [Center for X-ray Optics, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

2010-06-23T23:59:59.000Z

244

Deformation of Silica Aerogel During Fluid Adsorption  

E-Print Network [OSTI]

Aerogels are very compliant materials - even small stresses can lead to large deformations. In this paper we present measurements of the linear deformation of high porosity aerogels during adsorption of low surface tension fluids, performed using a Linear Variable Differential Transformer (LVDT). We show that the degree of deformation of the aerogel during capillary condensation scales with the surface tension, and extract the bulk modulus of the gel from the data. Furthermore we suggest limits on safe temperatures for filling and emptying low density aerogels with helium.

Tobias Herman; James Day; John Beamish

2005-06-30T23:59:59.000Z

245

Deformation development around mine roadways and simulation of roadway supports  

SciTech Connect (OSTI)

This paper describes the use of the sand and plaster physical modeling technique to investigate the deformation around mine roadways using a variety of support methods in a particular form of stress field. The characteristics and conditions of coal measures rock were considered prior to the preparation of the models and the insertion of support. The investigation has clearly shown how floor lift, roof failure and sidewall movements of mine roadways in laminated weak rock conditions gradually develops as a result of the increase in the stress and, also, how it is related to the level of support used.

Yasar, E.; Reddish, D.J. [Univ. of Nottingham (United Kingdom). Dept. of Mineral Resources Engineering; Daws, G. [Graham Daws Associates, Derbyshire (United Kingdom); Hayes, A.W. [H M Inspectorate of Mines, Merseyside (United Kingdom)

1995-11-01T23:59:59.000Z

246

Computational Modeling of Brain Dynamics during Repetitive Head Motions  

E-Print Network [OSTI]

Computational Modeling of Brain Dynamics during Repetitive Head Motions Igor Szczyrba School motions in traumatic scenarios that are as- sociated with severe brain injuries. Our results are based on the linear Kelvin-Voigt brain injury model, which treats the brain matter as a viscoelastic solid, and on our

Burtscher, Martin

247

Physics-Based Deformable Tongue Visualization  

E-Print Network [OSTI]

capture data gathered during speech production. Several novel deformation visualization techniques energy is utilized to provide an intuitive low dimensional visualization for the high dimensional sequential motion. Energy-interpolation-based morphing is also equipped to effectively highlight the subtle

Guo, Xiaohu "Tiger"

248

A COGNITIVE COMPENSATION MECHANSIM FOR DEFORMABLE ANTENNAS  

E-Print Network [OSTI]

This thesis presents the design, theory, and measurement of a linearly polarized microstrip patch antenna with a novel substrate-integrated mechanism that can compensate the detuning effects from a physical deformation. Specifically, this antenna...

Long, Stephen A.

2010-07-14T23:59:59.000Z

249

Supersymmetric Lorentz invariant deformations of superspaces  

E-Print Network [OSTI]

Lorentz invariant supersymmetric deformations of superspaces based on Moyal star product parametrized by Majorana spinor $\\lambda_{a}$ and Ramond grassmannian vector $\\psi_{m}=-{1\\over 2}(\\bar\\theta\\gamma_{m}\\lambda)$ in the spinor realization \\cite{VZ} are proposed. The map of supergravity background into composite supercoordinates: $(B^{-1}_{mn}, \\Psi^{a}_{m}, C_{ab}) \\leftrightarrow (i\\psi_{m}\\psi_{n}, \\psi_{m}\\lambda^{a}, \\lambda_{a}\\lambda_{b})$ valid up to the second order corrections in deformation parameter $h$ and transforming the background dependent Lorentz noninvariant (anti)commutators of supercoordinates into their invariant Moyal brackets is revealed. We found one of the deformations to depend on the axial vector $\\psi_{1m}={1/2}(\\bar\\theta\\gamma_{m}\\gamma_{5}\\lambda)$ and to vanish for the $\\theta$ components with the same chiralities. The deformations in the (super)twistor picture are discussed.

A. A. Zheltukhin

2005-12-30T23:59:59.000Z

250

Mechanics of deformation of carbon nanotubes  

E-Print Network [OSTI]

The deformation mechanics of multi-walled carbon nanotubes (MWCNT) and vertically aligned carbon nanotube (VACNT) arrays were studied using analytical and numerical methods. An equivalent orthotropic representation (EOR) ...

Garg, Mohit, S.M. Massachusetts Institute of Technology

2005-01-01T23:59:59.000Z

251

A fluid pressure and deformation analysis for geological sequestration of carbon dioxide  

SciTech Connect (OSTI)

We present a hydro-mechanical model and deformation analysis for geological sequestration of carbon dioxide. The model considers the poroelastic effects by taking into account the two-way coupling between the geomechanical response and the fluid flow process in greater detail. In order for analytical solutions, the simplified hydro-mechanical model includes the geomechanical part that relies on the theory of linear elasticity, while the fluid flow is based on the Darcy’s law. The model was derived through coupling the two parts using the standard linear poroelasticity theory. Analytical solutions for fluid pressure field were obtained for a typical geological sequestration scenario and the solutions for ground deformation were obtained using the method of Green’s function. Solutions predict the temporal and spatial variation of fluid pressure, the effect of permeability and elastic modulus on the fluid pressure, the ground surface uplift, and the radial deformation during the entire injection period.

Xu, Zhijie; Fang, Yilin; Scheibe, Timothy D.; Bonneville, Alain

2012-06-07T23:59:59.000Z

252

Author's personal copy Viscoelastic properties of model segments of collagen molecules  

E-Print Network [OSTI]

-up description of elastic and viscous properties form the properties of the tissue basic building blocks. © 2011 through the generation of muscular forces that are then transmitted to joints. The force transmission building block in vertebrates, and is the principal protein that provides mechanical stability, elasticity

Buehler, Markus J.

253

Modeling of three-dimensional viscoelastic flows with free surfaces using a finite element method  

E-Print Network [OSTI]

A framework and code have been developed to simulate fiber and film processes; the code can handle three-dimensional, isothermal, incompressible, creeping flow of a Giesekus fluid with free surfaces at infinite capillary ...

Adrian, David Joseph

2010-01-01T23:59:59.000Z

254

Modeling electrospinning process and a numerical scheme using Lattice Boltzmann method to simulate viscoelastic fluid flows  

E-Print Network [OSTI]

of secondary electric field on electrospinning process and whipping instability. It is observed that the external secondary field unwinds the jet spirals, reduces the whipping instability and increases the tension in the fiber. Lattice Boltzmann method (LBM...

Karra, Satish

2009-05-15T23:59:59.000Z

255

Deformable mirror for short wavelength applications  

DOE Patents [OSTI]

A deformable mirror compatible with short wavelength (extreme ultraviolet) radiation that can be precisely controlled to nanometer and subnanometer accuracy is described. Actuators are coupled between a reaction plate and a face plate which has a reflective coating. A control system adjusts the voltage supplied to the actuators; by coordinating the voltages supplied to the actuators, the reflective surface of the mirror can be deformed to correct for dimensional errors in the mirror or to produce a desired contour.

Chapman, Henry N. (2417 Kilkare Rd., Sunol, CA 94586); Sweeney, Donald W. (5020 Canyon Crest Dr., San Ramon, CA 94583)

1999-01-01T23:59:59.000Z

256

Maps between Deformed and Ordinary Gauge Fields  

E-Print Network [OSTI]

In this paper, we introduce a map between the q-deformed gauge fields defined on the GL$_{q}(N) $-covariant quantum hyperplane and the ordinary gauge fields. Perturbative analysis of the q-deformed QED at the classical level is presented and gauge fixing $\\grave{a} $ la BRST is discussed. An other star product defined on the hybrid $(q,h) $% -plane is explicitly constructed .

L. Mesref

2005-04-13T23:59:59.000Z

257

Deformation Behavior of Nanoporous Metals  

SciTech Connect (OSTI)

Nanoporous open-cell foams are a rapidly growing class of high-porosity materials (porosity {ge} 70%). The research in this field is driven by the desire to create functional materials with unique physical, chemical and mechanical properties where the material properties emerge from both morphology and the material itself. An example is the development of nanoporous metallic materials for photonic and plasmonic applications which has recently attracted much interest. The general strategy is to take advantage of various size effects to introduce novel properties. These size effects arise from confinement of the material by pores and ligaments, and can range from electromagnetic resonances to length scale effects in plasticity. In this chapter we will focus on the mechanical properties of low density nanoporous metals and how these properties are affected by length scale effects and bonding characteristics. A thorough understanding of the mechanical behavior will open the door to further improve and fine-tune the mechanical properties of these sometimes very delicate materials, and thus will be crucial for integrating nanoporous metals into products. Cellular solids with pore sizes above 1 micron have been the subject of intense research for many years, and various scaling relations describing the mechanical properties have been developed.[4] In general, it has been found that the most important parameter in controlling their mechanical properties is the relative density, that is, the density of the foam divided by that of solid from which the foam is made. Other factors include the mechanical properties of the solid material and the foam morphology such as ligament shape and connectivity. The characteristic internal length scale of the structure as determined by pores and ligaments, on the other hand, usually has only little effect on the mechanical properties. This changes at the submicron length scale where the surface-to-volume ratio becomes large and the effect of free surfaces can no longer be neglected. As the material becomes more and more constraint by the presence of free surfaces, length scale effects on plasticity become more and more important and bulk properties can no longer be used to describe the material properties. Even the elastic properties may be affected as the reduced coordination of surface atoms and the concomitant redistribution of electrons may soften or stiffen the material. If, and to what extend, such length scale effects control the mechanical behavior of nanoporous materials depends strongly on the material and the characteristic length scale associated with its plastic deformation. For example, ductile materials such as metals which deform via dislocation-mediated processes can be expected to exhibit pronounced length scale effects in the sub-micron regime where free surfaces start to constrain efficient dislocation multiplication. In this chapter we will limit our discussion to our own area of expertise which is the mechanical behavior of nanoporous open-cell gold foams as a typical example of nanoporous metal foams. Throughout this chapter we will review our current understanding of the mechanical properties of nanoporous open-cell foams including both experimental and theoretical studies.

Biener, J; Hodge, A M; Hamza, A V

2007-11-28T23:59:59.000Z

258

Influence of plastic deformation on bimaterial fault rupture directivity  

E-Print Network [OSTI]

Influence of plastic deformation on bimaterial fault rupture directivity Nora DeDontney,1 Elizabeth of the role of the stress state on the distribution of plastic deformation and the direction of preferred in determining the location of plastic deformation. For different orientations, plastic deformation can

Dmowska, Renata

259

A theory of amorphous polymeric solids undergoing large deformations: application to micro-indentation of poly(methyl methacrylate)  

E-Print Network [OSTI]

Although existing continuum models for the elasto-viscoplastic response of amorphous polymeric materials phenomenologically capture the large deformation response of these materials in a reasonably acceptable manner, they ...

Ames, N.M.

260

Synergistic Effect of coal blends on thermoplasticity evaluated using a temperature-variable dynamic viscoelastic measurement  

SciTech Connect (OSTI)

To maximize the conversion of low-quality coal into good coke, we investigated the thermoplasticity of various binary blends of caking coals with slightly or noncaking coals using a dynamic viscoelastic technique with a temperature-variable rheometer. Coal blend samples were prepared by mixing two coals (1:1 by weight), which were heated from room temperature to 600 C at a rate of 3-80{sup o}C/min. At the slow rate of 3{sup o}C/min, the blends had a tan {delta} that was generally lower than the calculated value, showing that a negative interaction caused a loss of thermoplasticity. In contrast, at the rapid heating rate of 80{sup o}C/min, the tan {delta} of some blends was higher than the calculated value, indicating a positive interaction that enhanced the thermoplasticity. With rapid heating, the thermoplasticity of each coal itself increased, and their thermoplastic temperature ranges widened with rapid heating. Therefore, rapid heating was effective at converting these coal blends into good cokes. Moreover, even with slow heating, when a combination of coals (Gregory:Enshu, 1:1) showing some thermoplasticity in nearly the same temperature range was blended, a desirable synergistic effect of the blend was obtained. This suggests that blending coal with an overlapping thermoplastic temperature range is important for the synergistic effect, regardless of the heating rate. 15 refs., 9 figs., 2 tabs.

Toshimasa Takanohashi; Takahiro Shishido; Ikuo Saito; Kensuke Masaki; Atsushi Dobashi; Kiyoshi Fukada [National Institute of Advanced Industrial Science and Technology, Tsukuba (Japan)

2006-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Limits of isotropic plastic deformation of Bangkok clay  

E-Print Network [OSTI]

A model assuming incremental plastic isotropic response has been recently proposed to model the deformation of isotropic packing of grains, in the small-strain range. It is used here on over-consolidated remould clay, to interpret the small-strain range behaviour obtained in [1,2] on Bangkok clay. The data published in [1,2] at constant volume are also used here to measure the size of the domain of validity in the (q/(M'p), p/po) plane, where po is the over-consolidation isotropic pressure, p is the mean stress and q the deviatoric stress, q . So, it is shown that the model works also for clay. This enlarges the application domain of model [3,4] to soft clay with OCR larger than 1.2 to 1.5. Pacs # : 45.70.-n ; 62.20.Fe ; 83.80.Fg, 83.80.Hj

P. Evesque

2005-07-08T23:59:59.000Z

262

Deformations of infrared-conformal theories in two dimensions  

E-Print Network [OSTI]

We study two exactly solvable two-dimensional conformal models, the critical Ising model and the Sommerfield model, on the lattice. We show that finite-size effects are important and depend on the aspect ratio of the lattice. In particular, we demonstrate how to obtain the correct massless behavior from an infinite tower of finite-size-induced masses and show that it is necessary to first take the cylindrical geometry limit in order to get correct results. In the Sommerfield model we also introduce a mass deformation to measure the mass anomalous dimension, $\\gamma_m$. We find that the explicit scale breaking of the lattice setup induces corrections which must be taken into account in order to reproduce $\\gamma_m$ at the infrared fixed point. These results can be used to improve the methodology in the search for the conformal window in QCD-like theories with many flavors.

Oscar Akerlund; Philippe de Forcrand

2014-10-05T23:59:59.000Z

263

Temperature and angular momentum dependence of the quadrupole deformation in sd-shell  

E-Print Network [OSTI]

Temperature and angular momentum dependence of the quadrupole deformation is studied in the middle of the sd-shell for 28Si and 27Si isotopes using the spherical shell model approach. The shell model calculations have been performed using the standard USD interaction and the canonical partition function constructed from the calculated eigen-solutions. It is shown that the extracted average quadrupole moments show a transitional behavior as a function of temperature and the inferred transitional temperature is shown to vary with angular-momentum. The quadrupole deformation of the individual eigen-states is also analyzed.

P. A. Ganai; J. A. Sheikh; I. Maqbool; R. P. Singh

2009-06-16T23:59:59.000Z

264

Semi-microscopic description of the double backbending in some deformed even-even rare earth nuclei  

E-Print Network [OSTI]

A semi-microscopic model to study the neutron and proton induced backbending phenomena in some deformed even-even nuclei from the rare earth region, is proposed. The space of particle-core states is defined by the angular momentum projection of a quadrupole deformed product state. The backbending phenomena are described by mixing four rotational bands, defined by a set of angular momentum projected states, and a model Hamiltonian describing a set of paired particles moving in a deformed mean field and interacting with a phenomenological deformed core. The ground band corresponds to the configuration where all particles are paired while the other rotational bands are built on one neutron or/and one proton broken pair. Four rare earth even-even nuclei which present the second anomaly in the observed moments of inertia are successfully treated within the proposed model.

R. Budaca; A. A. Raduta

2013-01-25T23:59:59.000Z

265

Plastic Deformation of 2D Crumpled Wires  

E-Print Network [OSTI]

When a single long piece of elastic wire is injected trough channels into a confining two-dimensional cavity, a complex structure of hierarchical loops is formed. In the limit of maximum packing density, these structures are described by several scaling laws. In this paper it is investigated this packing process but using plastic wires which give origin to completely irreversible structures of different morphology. In particular, it is studied experimentally the plastic deformation from circular to oblate configurations of crumpled wires, obtained by the application of an axial strain. Among other things, it is shown that in spite of plasticity, irreversibility, and very large deformations, scaling is still observed.

M A F Gomes; V P Brito; A S O Coelho; C C Donato

2008-11-17T23:59:59.000Z

266

Derivation of an optical potential for statically deformed rare-earth nuclei from a global spherical potential  

E-Print Network [OSTI]

The coupled-channel theory is a natural way of treating nonelastic channels, in particular those arising from collective excitations characterized by nuclear deformations. A proper treatment of such excitations is often essential to the accurate description of experimental nuclear-reaction data and to the prediction of a wide variety of scattering observables. Stimulated by recent work substantiating the near validity of the adiabatic approximation in coupled-channel calculations for scattering on statically deformed nuclei, we explore the possibility of generalizing a global spherical optical model potential (OMP) to make it usable in coupled-channel calculations on this class of nuclei. To do this, we have deformed the Koning-Delaroche global spherical potential for neutrons, coupling a sufficient number of states of the ground state band to ensure convergence. We present an extensive study of the effects of collective couplings and nuclear deformations on integrated cross sections as well as on angular distributions for neutron-induced reactions on statically deformed nuclei in the rare-earth region. We choose isotopes of three rare-earth elements (Gd, Ho, W), which are known to be nearly perfect rotors, to exemplify the results of the proposed method. Predictions from our model for total, elastic and inelastic cross sections, as well as for elastic and inelastic angular distributions, are in reasonable agreement with measured experimental data. These results suggest that the deformed Koning-Delaroche potential provides a useful regional neutron optical potential for the statically deformed rare earth nuclei.

G. P. A. Nobre; A. Palumbo; F. S. Dietrich; M. Herman; D. Brown; S. Hoblit

2014-12-22T23:59:59.000Z

267

PLASTIC DEFORMATION OF CRYSTALS: ANALYTICAL AND COMPUTER SIMULATION STUDIES OF DISLOCATION GLIDE  

E-Print Network [OSTI]

in Rate Processes in Plastic Deformation of Materials, J. C.PLASTIC DEFORMATION OF CRYSTALS: ANALYTICAL AND COMPUTERCAPTIONS FIGURES - iii - PLASTIC DEFORMATION OF CRYSTALS:

Altintas, Sabri

2011-01-01T23:59:59.000Z

268

Deformable geometry design with controlled mechanical property based on 3D printing.  

E-Print Network [OSTI]

??Deformable products exist broadly in different industries. These deformable products undergo deformation to achieve specific mechanical properties. Custom made insoles are applied to redistribute plantar… (more)

Li, Yongqiang

2014-01-01T23:59:59.000Z

269

Electric field Induced Patterns in Soft Visco-elastic films: From Long Waves of Viscous Liquids to Short Waves of Elastic Solids  

E-Print Network [OSTI]

We show that the electric field driven surface instability of visco-elastic films has two distinct regimes: (1) The visco-elastic films behaving like a liquid display long wavelengths governed by applied voltage and surface tension, independent of its elastic storage and viscous loss moduli, and (2) the films behaving like a solid require a threshold voltage for the instability whose wavelength always scales as ~ 4 x film thickness, independent of its surface tension, applied voltage, loss and storage moduli. Wavelength in a narrow transition zone between these regimes depends on the storage modulus.

N. Arun; Ashutosh Sharma; Partho S. G. Pattader; Indrani Banerjee; Hemant M. Dixit; K. S. Narayan

2009-06-02T23:59:59.000Z

270

Experimental deformation of natural and synthetic dolomite  

E-Print Network [OSTI]

Natural and hot isostatically pressed dolomite aggregates were experimentally deformed at effective pressures of Pe = 50 ?? 400 MPa, temperatures of 400 ?? 850??C, and strain rates of ?& = 1.2x10-4 s-1 to 1.2x10-7 s-1. Coarse- and fine-grained...

Davis, Nathan Ernest

2005-11-01T23:59:59.000Z

271

Ice deformation near SHEBA R. W. Lindsay  

E-Print Network [OSTI]

in the vicinity of the Surface Heat Budget of the Arctic Ocean (SHEBA) ice camp that is suitable for forcing factor for regional heat fluxes, ice growth and melt rates, and ice strength [Maykut, 1982Ice deformation near SHEBA R. W. Lindsay Polar Science Center, University of Washington, Seattle

Lindsay, Ron

272

FORMAL DEFORMATION THEORY 1. Introduction 1  

E-Print Network [OSTI]

. Lifts of objects 50 17. Schlessinger's theorem on prorepresentable functors 52 18. Infinitesimal paper [TV10], which discusses deformation theory with groupoids but in less generality than we do here is one that satisfies the infinitesimal lifting criterion for objects, see Section 8. This is analogous

de Jong, A. Johan

273

Joining of advanced materials by superplastic deformation  

DOE Patents [OSTI]

A method for utilizing superplastic deformation with or without a novel joint compound that leads to the joining of advanced ceramic materials, intermetallics, and cermets. A joint formed by this approach is as strong as or stronger than the materials joined. The method does not require elaborate surface preparation or application techniques.

Goretta, Kenneth C. (Downers Grove, IL); Routbort, Jules L. (Hinsdale, IL); Gutierrez-Mora, Felipe (Woodridge, IL)

2008-08-19T23:59:59.000Z

274

Deformation and Forming of Joined Materials  

SciTech Connect (OSTI)

Introductory article to a set of invited papers from the TMS committee on shaping and forming. This paper introduces a set of papers that were prepared to discussing the deformation and forming of joined materials, and to announce an upcoming symposium at the 2015 MS&T meeting in Columbus Ohio.

Carsley, John; Hovanski, Yuri; Clarke, Kester D.; Krajewski, Paul E.

2014-09-23T23:59:59.000Z

275

Mesh Puppetry: Cascading Optimization of Mesh Deformation with Inverse Kinematics  

E-Print Network [OSTI]

approach builds upon traditional rigging by optimizing skeleton position and vertex weights. Keywords: Mesh deformation, nonlinear optimization, inverse kinematics, geometry processing. 1 Introduction. To allow for more global and complex deforma- tion, many authors proposed to cast mesh deformation

Desbrun, Mathieu

276

Deformability of Plasmodium falciparum parasitized red blood cells  

E-Print Network [OSTI]

The biophysical properties of the human red blood cell (RBC) permit large deformations required for passage through narrow capillaries and spleen sinusoids. Several pathologic conditions alter RBC deformability that can ...

Mills, John Philip, Ph. D. Massachusetts Institute of Technology

2007-01-01T23:59:59.000Z

277

Microstructure-strength relationships of heavily deformed magnesium-lithium composites containing steel fibers  

SciTech Connect (OSTI)

The successful development of deformation-processed metal-metal composites (DMMC) offers the potential for ductile, high-strength structural materials with high-temperature stability. An infiltration casting process was used to permeate steel wool preforms with molten magnesium-lithium (Mg-Li) alloys. The selected matrix alloys were hexagonal close packed (HCP) Mg-4wt%Li or body centered cubic (BCC) Mg-12wt%Li; the low carbon steel wool fibers were predominantly BCC ferrite. These cast HCP/BCC and BCC/BCC composites were deformed by rolling or by extrusion and swaging. Mechanical properties, microstructure, and texture development of the composites were characterized at various levels of deformation. The HCP/BCC composites had limited formability at temperatures up to 400 C while the BCC/BCC composites had excellent formability during sheet rolling at room temperature but limited formability during swaging at room temperature. The tensile strengths of these HCP/BCC and BCC/BCC composite materials increased moderately with deformation, though less than predicted from rule of mixtures (ROM) calculations. The microstructure was characterized to correlate the filament size to the deformation strain and mechanical properties of the composite material. Stereological measurements of the filament size were used to adjust ROM calculations to reflect the actual deformation strain in the fibers. However, the experimental strengths of these composite materials were still less than ROM predictions, possibly due to the presence of considerably large fibers. Of the many models used to describe the strengthening observed in DMMC materials, the Hall-Petch relationship adequately described the experimental data. Texture development was also characterized to explain the deformation characteristics of the composite materials. Chapters 2, 3 and 4 are not included here. They are being processed separately.

Jensen, J.

1997-10-08T23:59:59.000Z

278

q-deformed logistic map with delay feedback  

E-Print Network [OSTI]

The delay logistic map with two types of q-deformations: Tsallis and Quantum-group type are studied. The stability of the map and its bifurcation scheme is analyzed as a function of the deformation and delay feedback parameters. Chaos is suppressed in a certain region of deformation and feedback parameter space. The steady state obtained by delay feedback is maintained in one type of deformation while chaotic behavior is recovered in another type with increasing delay.

Manish Dev Shrimali; Subhashish Banerjee

2012-03-14T23:59:59.000Z

279

Constitutive relationships for elastic deformation of clay rock: Data Analysis  

SciTech Connect (OSTI)

Geological repositories have been considered a feasible option worldwide for storing high-level nuclear waste. Clay rock is one of the rock types under consideration for such purposes, because of its favorable features to prevent radionuclide transport from the repository. Coupled hydromechanical processes have an important impact on the performance of a clay repository, and establishing constitutive relationships for modeling such processes are essential. In this study, we propose several constitutive relationships for elastic deformation in indurated clay rocks based on three recently developed concepts. First, when applying Hooke's law in clay rocks, true strain (rock volume change divided by the current rock volume), rather than engineering strain (rock volume change divided by unstressed rock volume), should be used, except when the degree of deformation is very small. In the latter case, the two strains will be practically identical. Second, because of its inherent heterogeneity, clay rock can be divided into two parts, a hard part and a soft part, with the hard part subject to a relatively small degree of deformation compared with the soft part. Third, for swelling rock like clay, effective stress needs to be generalized to include an additional term resulting from the swelling process. To evaluate our theoretical development, we analyze uniaxial test data for core samples of Opalinus clay and laboratory measurements of single fractures within macro-cracked Callovo-Oxfordian argillite samples subject to both confinement and water reduced swelling. The results from this evaluation indicate that our constitutive relationships can adequately represent the data and explain the related observations.

Liu, H.H.; Rutqvist, J.; Birkholzer, J.T.

2011-04-15T23:59:59.000Z

280

On a Model of Superconductivity and Biology  

E-Print Network [OSTI]

The paper deals with a semilinear integrodifferential equation that characterizes several dissipative models of Viscoelasticity, Biology and Superconductivity. The initial - boundary problem with Neumann conditions is analyzed. When the source term F is a linear function, then the explicit solution is obtained. When F is non linear, some results on existence, uniqueness and a priori estimates are deduced. As example of physical model the reaction - diffusion system of Fitzhugh Nagumo is considered.

Monica De Angelis

2012-03-02T23:59:59.000Z

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

The Role of Climate in the Deformation of a Fold and Thrust Belt  

E-Print Network [OSTI]

and uplifted in large folds. In order to test this and related ideas in a natural example, we have compared modeled rainfall to measured thrust sheet displacement, geometry, and internal deformation in the Appalachian fold and thrust belt. We use mean annual...

Steen, Sean Kristian

2012-02-14T23:59:59.000Z

282

Deformation patterns in thin films under uniform laser irradiation D. Walgraef  

E-Print Network [OSTI]

Deformation patterns in thin films under uniform laser irradiation D. Walgraef Mechanical to laser irradiation is described by a dynamical model that is based on coupled evolution equations la- ser damage of optical components, and nonuniform melting of semiconductor surfaces, to cite only

Ghoniem, Nasr M.

283

Path Planning for Deformable Linear Objects Mark Moll, Member, IEEE and Lydia E. Kavraki, Member, IEEE  

E-Print Network [OSTI]

-like robots. Index Terms-- path planning, deformation, minimal-energy curves, modeling, differential geometry of a wire subject to manipulation constraints. These configurations correspond to minimal-energy curves. By restricting the planner to minimal-energy curves, the execution of a path becomes easier. Our curve

Kavraki, Lydia E.

284

Learning Deformable Action Templates from Cluttered Videos Benjamin Yao and Song-Chun Zhu  

E-Print Network [OSTI]

Learning Deformable Action Templates from Cluttered Videos Benjamin Yao and Song-Chun Zhu cluttered real-world videos with weak supervisions. In our generative model, an action template human actions from real-world videos, we use a three- step semi-supervised learning procedure. 1

Zhu, Song Chun

285

Quantum Logic Gates using q-deformed Oscillators  

E-Print Network [OSTI]

We show that the quantum logic gates, {\\it viz.} the single qubit Hadamard and Phase Shift gates, can also be realised using q-deformed angular momentum states constructed via the Jordan-Schwinger mechanism with two q-deformed oscillators. {\\it Keywords :} quantum logic gates ; q-deformed oscillators ; quantum computation {\\it PACS:} 03.67.Lx ; 02.20.Uw

Debashis Gangopadhyay; Mahendra Nath Sinha Roy

2006-07-14T23:59:59.000Z

286

Partitioning a Deformed Urban Grid Leonard Hagger Ian Sanders  

E-Print Network [OSTI]

a convex map of the deformed urban grid. These algorithms are very similar and would #12;nd the same convex map of any given deformed urban grid. In this research I present two di#11;erent algorithms to solve this problem. Both are shown to #12;nd a signi#12;cantly better convex map of the deformed urban grid. The #12

Wismath, Stephen

287

Analysis of the Energy Spectra of Ground States of Deformed Nuclei in rare-earth region  

E-Print Network [OSTI]

The 62Sm, 64Gd, 64Dy, 70Y b, 72Hf and 74W nuclei are classified as deformed nuclei. Low-lying bands are one of the most fundamental excitation modes in the energy spectra of deformed nuclei. In this paper a theoretical analysis of the experimental data within the phenomenological model is presented. The energy spectra of ground states are calculated. It is found the low-lying spectra of ground band states are in good agreement with the experimental data.

Abdurahim A. Okhunov; G. I. Turaeva; M. U. Khandaker; Noora B. Rosli

2014-05-28T23:59:59.000Z

288

Neutrinoless Double Beta Decay in Heavy Deformed Nuclei  

E-Print Network [OSTI]

The zero neutrino mode of the double beta decay in heavy deformed nuclei is investigated in the framework of the pseudo SU(3) model, which has provided an accurate description of collective nuclear structure and predicted half-lives for the two neutrino mode in good agreement with experiments. In the case of $^{238}U$ the calculated zero neutrino half-life is at least three orders of magnitude greater than the two neutrino one, giving strong support of the identification of the radiochemically determined half-life as being the two neutrino double beta decay. For $^{150}Nd$ the zero neutrino matrix elements are of the order of magnitude of, but lesser than, those evaluated using the QRPA. This result confirms that different nuclear models produce similar zero neutrino matrix elements, contrary to the two neutrino case. Using these pseudo SU(3) results and the upper limit for the neutrino mass we estimate the $\\beta\\beta_{0\

Jorge G. Hirsch; O. Castaños; P. O. Hess

1994-07-12T23:59:59.000Z

289

A new deformed Schioberg-type potential and ro-vibrational energies for some diatomic molecules  

E-Print Network [OSTI]

We suggest a new deformed Schioberg-type potential for diatomic molecules. We show that it is equivalent to Tietz-Hua oscillator potential. We discuss how to relate our deformed Schioberg potential to Morse, to Deng-Fan, to the improved Manning-Rosen, and to the deformed modified Rosen-Morse potential models. We transform our potential into a proper form and use the supersymmetric quantization to find a closed form analytical solution for the ro-vibrational energy levels that are highly accurate over a wide range of vibrational and rotational quantum numbers. We discuss our results using 6-diatomic molecules H2, HF, N2, NO, O2, and O2. Our results turn out to compare excellently with those from a generalized pseudospectral numerical method.

Omar Mustafa

2014-09-24T23:59:59.000Z

290

Aharonov-Bohm interferences from local deformations in graphene  

E-Print Network [OSTI]

One of the most interesting aspects of graphene is the tied relation between structural and electronic properties. The observation of ripples in the graphene samples both free standing and on a substrate has given rise to a very active investigation around the membrane-like properties of graphene and the origin of the ripples remains as one of the most interesting open problems in the system. The interplay of structural and electronic properties is successfully described by the modelling of curvature and elastic deformations by fictitious gauge fields that have become an ex- perimental reality after the suggestion that Landau levels can form associated to strain in graphene and the subsequent experimental confirmation. Here we propose a device to detect microstresses in graphene based on a scanning-tunneling-microscopy setup able to measure Aharonov-Bohm inter- ferences at the nanometer scale. The interferences to be observed in the local density of states are created by the fictitious magnetic field associated to elastic deformations of the sample.

Fernando de Juan; Alberto Cortijo; María A. H. Vozmediano; Andrés Cano

2011-05-04T23:59:59.000Z

291

Structural deformation in the offshore Santa Maria basin, California  

SciTech Connect (OSTI)

The authors divide the offshore Santa Maria basin into the southern, central, and northern provinces based on the pattern, style, and timing of late Cenozoic deformation. From their analyses of over 2,000 km of CDP seismic data and offshore well data they prepared time structure contour maps for three basin-wide unconformities: top of basement, top of Miocene, and the unconformity between early and late Pliocene chronostratigraphic units. Isochron maps were constructed between these horizons and between the early/late Pliocene unconformity and the sea floor to evaluate timing of the deformation. All maps were converted to depth and isopach values based on a three-dimensional velocity model. The regional structure contour and isopach maps show that the offshore Santa Maria basin is characterized by localized crustal shortening orthogonal to the Pacific/North America plate margin and indications of post-Miocene to recent lateral slip along the eastern basin boundary, the San Simeon/Hosgri fault system.

Willingham, C.R. (Explorametrics, Carpinteria, CA (United States)); Heck, R.G. (R.G. Heck and Associates, Carpinteria, CA (United States)); Rietman, J.M. (Rietman Consultants, Santa Ana, CA (United States))

1991-02-01T23:59:59.000Z

292

A Search for Channel Deformation in Irradiated Vanadium Tensile Specimens  

SciTech Connect (OSTI)

A miniature tensile specimen of V-4Cr-4Ti which had be irradiated in the 17J test at 425°C to 3.7 dpa was mechanically polished, deformed to 3.9% strain at room temperature, and examined by scanning and transmission electron microscopy in order to look for evidence of channel deformation. It was found that uniform deformation can occur without channel deformation, but evidence for channeling was found with channels appearing most prominently after the onset of necking. The channeling occurs on wavy planes with large variations in localized deformation from channel to channel.

Gelles, David S.; Toloczko, Mychailo B.; Kurtz, Richard J.

2010-02-26T23:59:59.000Z

293

Uniformly accelerated detector in the $?$-deformed Dirac vacuum  

E-Print Network [OSTI]

In this paper, we investigate how a uniformly accelerated detector responds to vacuum state of a Dirac field in the $\\kappa$-Minkowski space-time. Starting from $\\kappa$-deformed Dirac theory, which is invariant under $\\kappa$-Poincare algebra, we derive $\\kappa$-deformed Wightmann function for Dirac field, which is valid up to first order in the deformation parameter $a$. Using this, we calculate the response function of the uniformly accelerated detector, which is coupled to massless Dirac field in $\\kappa$-spacetime. From this, we obtain the modification to Unruh effect for the $\\kappa$-deformed Dirac field, valid up to first order in the deformation parameter.

E. Harikumar; Ravikant Verma

2012-11-19T23:59:59.000Z

294

Modeling Hot Mix Asphalt Compaction Using a Thermodynamics Based Compressible Viscoelastic Model within the Framework of Multiple Natural Configurations  

E-Print Network [OSTI]

asphalt (HMA) using the notion of multiple natural configurations. A thermodynamic framework is employed to study the non-linear dissipative response associated with HMA by specifying the forms for the stored energy and the rate of dissipation function...

Koneru, Saradhi

2011-10-21T23:59:59.000Z

295

Biaxially textured articles formed by plastic deformation  

DOE Patents [OSTI]

A method of preparing a biaxially textured article comprises the steps of providing a metal preform, coating or laminating the preform with a metal layer, deforming the layer to a sufficient degree, and rapidly recrystallizing the layer to produce a biaxial texture. A superconducting epitaxial layer may then be deposited on the biaxial texture. In some embodiments the article further comprises buffer layers, electromagnetic devices or electro-optical devices.

Goyal, Amit (Knoxville, TN)

2001-01-01T23:59:59.000Z

296

On compact generation of deformed schemes.  

E-Print Network [OSTI]

We obtain a theorem which allows to prove compact generation of derived categories of Grothendieck categories, based upon certain coverings by localizations. This theorem follows from an application of Rouquier's cocovering theorem in the triangulated context, and it implies Neeman's result on compact generation of quasi-compact separated schemes. We prove an application of our theorem to non-commutative deformations of such schemes, based upon a change from Koszul complexes to Chevalley-Eilenberg complexes.

Wendy Lowen; Michel Van den Bergh

297

Shock wave absorber having a deformable liner  

DOE Patents [OSTI]

This invention discloses a shock wave absorber for a piping system carrying liquid. The absorber has a plastically deformable liner defining the normal flow boundary for an axial segment of the piping system, and a nondeformable housing is spaced outwardly from the liner so as to define a gas-tight space therebetween. The flow capacity of the liner generally corresponds to the flow capacity of the piping system line, but the liner has a noncircular cross section and extends axially of the piping system line a distance between one and twenty times the diameter thereof. Gas pressurizes the gas-tight space equal to the normal liquid pressure in the piping system. The liner has sufficient structural capacity to withstand between one and one-half and two times this normal liquid pressures; but at greater pressures it begins to plastically deform initially with respect to shape to a more circular cross section, and then with respect to material extension by circumferentially stretching the wall of the liner. A high energy shock wave passing through the liner thus plastically deforms the liner radially into the gas space and progressively also as needed in the axial direction of the shock wave to minimize transmission of the shock wave beyond the absorber.

Youngdahl, C.K.; Wiedermann, A.H.; Shin, Y.W.; Kot, C.A.; Ockert, C.E.

1983-08-26T23:59:59.000Z

298

q-Deformed KP Hierarchy and q-Deformed Constrained KP Hierarchy  

E-Print Network [OSTI]

Using the determinant representation of gauge transformation operator, we have shown that the general form of $\\tau$ function of the $q$-KP hierarchy is a q-deformed generalized Wronskian, which includes the q-deformed Wronskian as a special case. On the basis of these, we study the q-deformed constrained KP ($q$-cKP) hierarchy, i.e. $l$-constraints of $q$-KP hierarchy. Similar to the ordinary constrained KP (cKP) hierarchy, a large class of solutions of $q$-cKP hierarchy can be represented by q-deformed Wronskian determinant of functions satisfying a set of linear $q$-partial differential equations with constant coefficients. We obtained additional conditions for these functions imposed by the constraints. In particular, the effects of $q$-deformation ($q$-effects) in single $q$-soliton from the simplest $\\tau$ function of the $q$-KP hierarchy and in multi-$q$-soliton from one-component $q$-cKP hierarchy, and their dependence of $x$ and $q$, were also presented. Finally, we observe that $q$-soliton tends to the usual soliton of the KP equation when $x\\to 0$ and $q\\to 1$, simultaneously.

Jingsong He; Yinghua Li; Yi Cheng

2006-06-15T23:59:59.000Z

299

Deformation of Diopside Single Crystal at Mantle Pressure 2 TEM Characterization of Deformation Microstructures  

SciTech Connect (OSTI)

The dislocation microstructures of diopside single crystals deformed at high-pressure (4 {<=} P {<=} 9 GPa), high-temperature (1100{sup o} {<=} T {<=} 1400 {sup o}C) using a Deformation-DIA high-pressure apparatus (D-DIA) have been characterized by transmission electron microscopy using weak-beam dark-field (WBDF), precession electron diffraction (PED), large-angle convergent-beam electron diffraction (LACBED) and the thickness-fringe method. Dislocation glide is the dominant deformation mechanism under these conditions. The 1/2<110>{l_brace}110{r_brace} glide is controlled by lattice friction on the edge segments and shows extensive cross-slip. The [001] glide occurs mostly on {l_brace}110{r_brace}; no evidence for [001](010) glide has been found. The [100] dislocations bear a strong lattice friction probably due to complex (out of glide) core structures.

E Amiguet; P Cordier; P Raterron

2011-12-31T23:59:59.000Z

300

Effects of gaps in adhesives that bond elastically deformed panels to parabolic, cylindrical substructures  

SciTech Connect (OSTI)

In previous studies of the mechanical behavior of line focusing solar collectors, the reflective surface panel was modeled as a thin, initially flat, elastic plate that underwent large displacements to attain the shape of a prescribed parabolic cylinder. Attention was focused upon the stresses that developed in an adhesive layer which bonded the deformed panel to a rigid, parabolic substructure. Among the myriad possible collector designs, some possess longitudinally oriented, hollow ribs or corrugations in the substructure which interrupt the transverse continuity of the bond line between the deformed panel and the substructure. Thus, finite gaps in the adhesive are present which create regions where the panel surface becomes intermittently supported. The presence of these gaps perturbs the otherwise smooth distribution of adhesive contact stresses and it is the analytical modeling of this behavior that is the subject of the present report. In particular, attention is devoted to gaps which overlap with the edge effect zone - a region near the rim or vertex of the deformed panel where, in the absence of uniform edge loads necessary to maintain a true parabolic shape, high stresses and associated deformations occur. Significant influences of the gap size and position in the edge effect zone are demonstrated and discussed.

Wilson, R.K.; Reuter, R.C. Jr.

1982-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

A Simulator with Numerical Upscaling for the Analysis of Coupled Multiphase Flow and Geomechanics in Heterogeneous and Deformable Porous and Fractured Media  

E-Print Network [OSTI]

multi-dimensional rock deformation. A coupled flow and geomechanics model considers flow physics and rock physics simultaneously by cou-pling different types of partial differential equations through primary variables. A number of coupled flow...

Yang, Daegil

2013-07-15T23:59:59.000Z

302

Constitutive Behavior of a Twaron® Fabric/Natural Rubber Composite: Experiments and Modeling  

E-Print Network [OSTI]

-mechanisms and molecular features on the macroscopic responses of ballistic fabrics. In the present work, the constitutive behavior of Twaron CT709® fabric/natural rubber (Twaron®/NR) composite is studied using three viscoelasticity models (i.e., a four-parameter Burgers...

Natarajan, Valliyappan D.

2011-02-22T23:59:59.000Z

303

IEEE TRANSACTIONS ON ROBOTICS, VOL. 22, NO. 4, AUGUST 2006 625 Path Planning for Deformable Linear Objects  

E-Print Network [OSTI]

--Deformation, differential geometry, flexible ma- nipulation, flexible object representation, minimal-energy curves, modeling with previous approaches. Using a simplified model for obstacles, we can find minimal-energy curves of fixed. These config- urations correspond to minimal-energy curves. By restricting the planner to minimal-energy curves

Moll, Mark

304

ROCK DEFORMATION 2010 GORDON RESEARCH CONFERENCE, AUGUST 8-13, 2010  

SciTech Connect (OSTI)

Creep in the crust and mantle is commonly considered a steady-state process. This view prevails despite the fact that earthquakes do not represent steady-state and at the base of the seismogenic zone, for example, the stresses that drive creep must vary with the earthquake cycle. The contribution of transient versus steady-state behavior is not easy to determine from naturally-deformed brittle or plastic rocks and our view of steady-state depends on whether we consider geological or shorter time-scales. Perhaps we avoid a non steady-state picture because we lack appropriate descriptive or quantitative tools. The aim of the 2010 Gordon Research Conference (GRC) in rock deformation is to explore what we know about non steady-state deformation and how we might advance our understanding through geological and geophysical field investigations, laboratory experiments and modeling. This will require an appraisal of the applicability of steady-state concepts as well as an exploration of transient behavior, in which processes and physical properties cycle between different states as might be the case during earthquake cycles, and transitions in behavior, where finite strain or changing environmental conditions lead to changes in processes and properties. Conference sessions will cover seven broad and interlinked topics. (1) What is steady state?; an appraisal of applicability of the steady-state concept in rock deformation. (2) Seismogenic Faulting and Brittle Fault Rocks; where transience in rates and conditions are accepted but not fully understood. (3) Episodic Creep During the Seismic Cycle; with a focus on processes in areas adjacent to the base of the seismogenic zone. (4) Creep in Zones of Stress and Temperature Cycling; considering deformation in real-world complex systems (5) Deformation, Metamorphism, and Fluids; exploring the interaction of diagenesis/metamorphism and thermal instabilities with deformation. (6) Mechanism and Microstructure Transitions During Deformation; quantifying evolution as a function of strain and associated with changes in deformation kinematics or conditions. (7) Mechanism and Microstructure Transitions Related to Mantle Geophysics; with a focus on the link between mechanisms affecting processes on geological time-scales on the time-scales associated with seismic wave propagation. The GRC on Rock Deformation aims to bring together researchers with diverse expertise, and to shape the scientific debate and provide inspiration for young researchers to fill the still extensive gaps in our knowledge of how the Earth deforms. The processes that will be discussed have wide applications in both basic and applied research. A key issue, of fundamental importance to our understanding of the Earth, for discussion at this meeting will be the transition from time-dependent (and distributed) rock deformation, including both high temperature creep and brittle creep, to episodic (and more localized) events. Such transitions have both a scientific and a socio-economic impact since they control the precursory phases of important geohazards such as earthquake rupture and volcanic eruptions, and also influence effective recovery of hydrocarbon and geothermal energy resources, and the integrity of long-term storage facilities for hazardous waste.

David Prior

2010-08-13T23:59:59.000Z

305

Kinetic bounding volume hierarchies for deformable objects  

E-Print Network [OSTI]

We present novel algorithms for updating bounding volume hierarchies of objects undergoing arbitrary deformations. Therefore, we introduce two new data structures, the kinetic AABB tree and the kinetic BoxTree. The event-based approach of the kinetic data structures framework enables us to show that our algorithms are optimal in the number of updates. Moreover, we show a lower bound for the total number of BV updates, which is independent of the number of frames. We used our kinetic bounding volume hierarchies for collision detection and performed a comparison with the classical bottomup update method. The results show that our algorithms perform up to ten times faster in practically relevant scenarios.

Gabriel Zachmann; Tu Clausthal

2006-01-01T23:59:59.000Z

306

A novel digital tomosynthesis (DTS) reconstruction method using a deformation field map  

SciTech Connect (OSTI)

We developed a novel digital tomosynthesis (DTS) reconstruction method using a deformation field map to optimally estimate volumetric information in DTS images. The deformation field map is solved by using prior information, a deformation model, and new projection data. Patients' previous cone-beam CT (CBCT) or planning CT data are used as the prior information, and the new patient volume to be reconstructed is considered as a deformation of the prior patient volume. The deformation field is solved by minimizing bending energy and maintaining new projection data fidelity using a nonlinear conjugate gradient method. The new patient DTS volume is then obtained by deforming the prior patient CBCT or CT volume according to the solution to the deformation field. This method is novel because it is the first method to combine deformable registration with limited angle image reconstruction. The method was tested in 2D cases using simulated projections of a Shepp-Logan phantom, liver, and head-and-neck patient data. The accuracy of the reconstruction was evaluated by comparing both organ volume and pixel value differences between DTS and CBCT images. In the Shepp-Logan phantom study, the reconstructed pixel signal-to-noise ratio (PSNR) for the 60 deg. DTS image reached 34.3 dB. In the liver patient study, the relative error of the liver volume reconstructed using 60 deg. projections was 3.4%. The reconstructed PSNR for the 60 deg. DTS image reached 23.5 dB. In the head-and-neck patient study, the new method using 60 deg. projections was able to reconstruct the 8.1 deg. rotation of the bony structure with 0.0 deg. error. The reconstructed PSNR for the 60 deg. DTS image reached 24.2 dB. In summary, the new reconstruction method can optimally estimate the volumetric information in DTS images using 60 deg. projections. Preliminary validation of the algorithm showed that it is both technically and clinically feasible for image guidance in radiation therapy.

Ren Lei; Zhang Junan; Thongphiew, Danthai; Godfrey, Devon J.; Jackie Wu, Q.; Zhou Sumin; Yin Fangfang [Department of Radiation Oncology, Duke University Medical Center, DUMC Box 3295, Durham, North Carolina, 27710 (United States) and Duke Medical Physics Graduate Program, 2424 Erwin Road Suite 101, Durham, North Carolina 27705 (United States); Department of Radiation Oncology, Duke University Medical Center, DUMC Box 3295, Durham, North Carolina 27710 (United States); Department of Radiation Oncology, Duke University Medical Center, DUMC Box 3295, Durham, North Carolina, 27710 (United States) and Duke Medical Physics Graduate Program, 2424 Erwin Road Suite 101, Durham, North Carolina 27705 (United States)

2008-07-15T23:59:59.000Z

307

EXAMINATION OF POSTIRRADIATION DEFORMATION MICROSTRUCTURES IN F82H  

SciTech Connect (OSTI)

The deformed microstructures of irradiated F82H uniaxial tensile specimens have been examined following irradiation in HFR to 2.6 dpa at 32 C in order to identify controlling mechanisms. Deformation following irradiation is found to occur in poorly defined channels, causing formation of discrete steps at surfaces, similar to that in unirradiated steel. Deformation is by motion of individual a/2<111> dislocations.

Gelles, David S.; Schaublin, R.

2002-09-01T23:59:59.000Z

308

Free motion in deformed (quantum) four-dimensional space  

E-Print Network [OSTI]

It is shown that trajectories of free motion of the particles in deformed ("quantum") four dimensional space-time are quadratic curves.

A. N. Leznov

2007-07-23T23:59:59.000Z

309

ankle deformity secondary: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

in the Trapezium Cluster: First Scientific Results from the MMT Deformable Secondary Mirror Adaptive Optics System Astrophysics (arXiv) Summary: We present the first scientific...

310

Ruthenium Aluminides: Deformation Mechanisms and Substructure Development  

SciTech Connect (OSTI)

Structural and functional materials that can operate in severe, high temperature environments are key to the operation of a wide range of energy generation systems. Because continued improvements in the energy efficiency of these systems is critical, the need for new materials with higher temperature capabilities is inevitable. Intermetallic compounds, with strong bonding and generally high melting points offer this possibility for a broad array of components such as coatings, electrode materials, actuators and/or structural elements. RuAl is a very unusual intermetallic compound among the large number of B2compounds that have been identified and investigated to date. This material has a very high melting temperature of 2050?C, low thermal expansion, high thermal conductivity and good corrosion resistance. Unlike most other high temperature B2 intermetallics, RuAl possesses good intrinsic deformability at low temperatures. In this program fundamental aspects of low and high temperature mechanical properties and deformation mechanisms in binary and higher order RuAl-based systems have been investigated. Alloying additions of interest included platinum, boron and niobium. Additionally, preliminary studies on high temperature oxidation behavior of these materials have been conducted.

Tresa M. Pollock

2005-05-11T23:59:59.000Z

311

A method to estimate the effect of deformable image registration uncertainties on daily dose mapping  

SciTech Connect (OSTI)

Purpose: To develop a statistical sampling procedure for spatially-correlated uncertainties in deformable image registration and then use it to demonstrate their effect on daily dose mapping. Methods: Sequential daily CT studies are acquired to map anatomical variations prior to fractionated external beam radiotherapy. The CTs are deformably registered to the planning CT to obtain displacement vector fields (DVFs). The DVFs are used to accumulate the dose delivered each day onto the planning CT. Each DVF has spatially-correlated uncertainties associated with it. Principal components analysis (PCA) is applied to measured DVF error maps to produce decorrelated principal component modes of the errors. The modes are sampled independently and reconstructed to produce synthetic registration error maps. The synthetic error maps are convolved with dose mapped via deformable registration to model the resulting uncertainty in the dose mapping. The results are compared to the dose mapping uncertainty that would result from uncorrelated DVF errors that vary randomly from voxel to voxel. Results: The error sampling method is shown to produce synthetic DVF error maps that are statistically indistinguishable from the observed error maps. Spatially-correlated DVF uncertainties modeled by our procedure produce patterns of dose mapping error that are different from that due to randomly distributed uncertainties. Conclusions: Deformable image registration uncertainties have complex spatial distributions. The authors have developed and tested a method to decorrelate the spatial uncertainties and make statistical samples of highly correlated error maps. The sample error maps can be used to investigate the effect of DVF uncertainties on daily dose mapping via deformable image registration. An initial demonstration of this methodology shows that dose mapping uncertainties can be sensitive to spatial patterns in the DVF uncertainties.

Murphy, Martin J.; Salguero, Francisco J.; Siebers, Jeffrey V.; Staub, David; Vaman, Constantin [Department of Radiation Oncology, Virginia Commonwealth University, Richmond Virginia 23298 (United States)

2012-02-15T23:59:59.000Z

312

The role of electron-screening deformations in solar nuclear fusion reactions and the solar neutrino puzzle  

E-Print Network [OSTI]

Thermonuclear fusion reaction rates in the solar plasma are enhanced by the presence of the electron cloud that screens fusing nuclei. The present work studies the influence of electron screening deformations on solar reaction rates in the framework of the Debye-Huckel model. These electron-ion cloud deformations, assumed here to be static and axially symmetric, are shown to be able to considerably influence the solar neutrino fluxes of the pp and the CNO chains, with reasonable changes in the macroscopic parameters of the standard solar model (SSM) . Various known deformation sources are discussed but none of them is found strong enough to have a significant impact on the SSM neutrino fluxes.

Theodore E. Liolios

2000-08-13T23:59:59.000Z

313

Fractal nature of multiple shear bands in severely deformed metallic glass  

SciTech Connect (OSTI)

We present an analysis of fractal geometry of extensive and complex shear band patterns in a severely deformed metallic glass. We show that the shear band patterns have fractal characteristics, and the fractal dimensions are determined by the stress noise induced by the interaction between shear bands. A theoretical model of the spatial evolution of multiple shear bands is proposed in which the collective shear bands slide is considered as a stochastic process far from thermodynamic equilibrium.

Sun, B. A.; Wang, W. H. [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

2011-05-16T23:59:59.000Z

314

Plastic deformation in Al (Cu) interconnects stressed by electromigration and studied by synchrotron polychromatic X-ray microdiffraction  

E-Print Network [OSTI]

Plastic deformation in Al (Cu) interconnects stressed bygrain orientation [7], study plastic deformation [12-15] andThis aspect of EM-induced plastic deformation in grains

Chen, Kai; Advanced Light Source; UCLA

2008-01-01T23:59:59.000Z

315

DEFORMED MACDONALD-RUIJSENAARS OPERATORS AND SUPER MACDONALD POLYNOMIALS  

E-Print Network [OSTI]

DEFORMED MACDONALD-RUIJSENAARS OPERATORS AND SUPER MACDONALD POLYNOMIALS A.N. SERGEEV AND A.P. VESELOV Abstract. It is shown that the deformed Macdonald-Ruijsenaars op- erators can be described as the restrictions on certain affine subvarieties of the usual Macdonald-Ruijsenaars operator in infinite number

316

Micrographic detection of plastic deformation in nickel base alloys  

DOE Patents [OSTI]

A method for detecting low levels of plastic deformation in metal articles comprising electrolytically etching a flow free surface of the metal article with nital at a current density of less than about 0.1 amp/cm.sup.2 and microscopically examining the etched surface to determine the presence of alternating striations. The presence of striations indicates plastic deformation in the article.

Steeves, Arthur F. (Schenectady, NY); Bibb, Albert E. (Clifton Park, NY)

1984-01-01T23:59:59.000Z

317

Image Deformation Using Moving Least Squares Scott Schaefer  

E-Print Network [OSTI]

: · Interpolation: The handles p should map directly to q under deformation. (i.e; f (pi) = qi). · Smoothness: f should be the identity function. (i.e; qi = pi f (v) = v). These properties are very similar to thoseImage Deformation Using Moving Least Squares Scott Schaefer Texas A&M University Travis Mc

Schaefer, Scott

318

Image Deformation Using Moving Least Squares Scott Schaefer  

E-Print Network [OSTI]

: The handles p should map directly to q under deformation. (i.e; f(pi) = qi). · Smoothness: f should produce be the identity function. (i.e; qi = pi f(v) = v). These properties are very similar to those used in scatteredImage Deformation Using Moving Least Squares Scott Schaefer Texas A&M University Travis Mc

Warren, Joe

319

Granite ascent and emplacement during contractional deformation in convergent orogens  

E-Print Network [OSTI]

Granite ascent and emplacement during contractional deformation in convergent orogens MICHAEL BROWN of granite melt through the crust in convergent orogens. During contractional deformation, ¯ow of melt to weakly discordant irregular granite sheets occur in zones of higher strain, which suggests percolative

Solar, Gary S.

320

DESCRIBING THE PLASTIC DEFORMATION OF ALUMINUM SOFTBALL BATS  

E-Print Network [OSTI]

DESCRIBING THE PLASTIC DEFORMATION OF ALUMINUM SOFTBALL BATS E. BIESEN1 AND L. V. SMITH2 Washington-mail: lvsmith@wsu.edu Hollow aluminum bats were introduced over 30 years ago to provide improved durability over durability. Accordingly, the plastic deformation from a ball impact of a single-wall aluminum bat

Smith, Lloyd V.

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
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to obtain the most current and comprehensive results.


321

Tetrahedral Mesh Generation for Deformable Bodies Neil Molino  

E-Print Network [OSTI]

, the finite element method or an optimization approach to relax the positions of both the interior refinement, finite element method, level set methods 1 Introduction Tetrahedral meshes are used in a number for fluid flow and heat transfer where the mesh is not deformed, and for small deformation solids where

Stanford University

322

High stroke pixel for a deformable mirror  

DOE Patents [OSTI]

A mirror pixel that can be fabricated using standard MEMS methods for a deformable mirror. The pixel is electrostatically actuated and is capable of the high deflections needed for spaced-based mirror applications. In one embodiment, the mirror comprises three layers, a top or mirror layer, a middle layer which consists of flexures, and a comb drive layer, with the flexures of the middle layer attached to the mirror layer and to the comb drive layer. The comb drives are attached to a frame via spring flexures. A number of these mirror pixels can be used to construct a large mirror assembly. The actuator for the mirror pixel may be configured as a crenellated beam with one end fixedly secured, or configured as a scissor jack. The mirror pixels may be used in various applications requiring high stroke adaptive optics.

Miles, Robin R.; Papavasiliou, Alexandros P.

2005-09-20T23:59:59.000Z

323

Neutron shell structure and deformation in neutron-drip-line nuclei  

E-Print Network [OSTI]

Neutron shell-structure and the resulting possible deformation in the neighborhood of neutron-drip-line nuclei are systematically discussed, based on both bound and resonant neutron one-particle energies obtained from spherical and deformed Woods-Saxon potentials. Due to the unique behavior of weakly-bound and resonant neutron one-particle levels with smaller orbital angular-momenta $\\ell$, a systematic change of the shell structure and thereby the change of neutron magic-numbers are pointed out, compared with those of stable nuclei expected from the conventional j-j shell-model. For spherical shape with the operator of the spin-orbit potential conventionally used, the $\\ell_{j}$ levels belonging to a given oscillator major shell with parallel spin- and orbital-angular-momenta tend to gather together in the energetically lower half of the major shell, while those levels with anti-parallel spin- and orbital-angular-momenta gather in the upper half. The tendency leads to a unique shell structure and possible deformation when neutrons start to occupy the orbits in the lower half of the major shell. Among others, the neutron magic-number N=28 disappears and N=50 may disappear, while the magic number N=82 may presumably survive due to the large $\\ell =5$ spin-orbit splitting for the $1h_{11/2}$ orbit. On the other hand, an appreciable amount of energy gap may appear at N=16 and 40 for spherical shape, while neutron-drip-line nuclei in the region of neutron number above N=20, 40 and 82, namely N $\\approx$ 21-28, N $\\approx$ 41-54, and N $\\approx$ 83-90, may be quadrupole-deformed though the possible deformation depends also on the proton number of respective nuclei.

Ikuko Hamamoto

2012-06-18T23:59:59.000Z

324

Deformation-induced accelerated dynamics in polymer glasses  

E-Print Network [OSTI]

Molecular dynamics simulations are used to investigate the effects of deformation on the segmental dynamics in an aging polymer glass. Individual particle trajectories are decomposed into a series of discontinuous hops, from which we obtain the full distribution of relaxation times and displacements under three deformation protocols: step stress (creep), step strain, and constant strain rate deformation. As in experiments, the dynamics can be accelerated by several orders of magnitude during deformation, and the history dependence is entirely erased during yield (mechanical rejuvenation). Aging can be explained as a result of the long tails in the relaxation time distribution of the glass, and similarly, mechanical rejuvenation is understood through the observed narrowing of this distribution during yield. Although the relaxation time distributions under deformation are highly protocol specific, in each case they may be described by a universal acceleration factor that depends only on the strain.

Mya Warren; Joerg Rottler

2010-08-16T23:59:59.000Z

325

Interfacial deformation and jetting of a magnetic fluid  

E-Print Network [OSTI]

An attractive technique for forming and collecting aggregates of magnetic material at a liquid--air interface by an applied magnetic field gradient was recently addressed theoretically and experimentally [Soft Matter, (9) 2013, 8600-8608]: when the magnetic field is weak, the deflection of the liquid--air interface has a steady shape, while for sufficiently strong fields, the interface destabilizes and forms a jet that extracts magnetic material. Motivated by this work, we develop a numerical model for the closely related problem of solving two-phase Navier--Stokes equations coupled with the static Maxwell equations. We computationally model the forces generated by a magnetic field gradient produced by a permanent magnet and so determine the interfacial deflection of a magnetic fluid (a pure ferrofluid system) and the transition into a jet. We analyze the shape of the liquid--air interface during the deformation stage and the critical magnet distance for which the static interface transitions into a jet. We d...

Afkhami, Shahriar; Griffiths, Ian M

2015-01-01T23:59:59.000Z

326

Modeling Of Surface Deformation From Satellite Radar Interferometry...  

Open Energy Info (EERE)

interferometric synthetic aperture radar) analysis of two-year Radarsat satellite data covering the period May 2006 - March 2008. SAR scenes from two orbit geometries are...

327

Neural network modelling of hot deformation of austenite  

E-Print Network [OSTI]

Professor A. H. Windle for the provision of laboratory facilities in the department of Materials Science. Phil. course, either in organising the course in this first year or by lecturing. 6 #12;Abstract logarithms exp10 base 10 exponential function Q activation energy G Free energy F Helmholtz energy F force

Cambridge, University of

328

Modeling Of Surface Deformation From Satellite Radar Interferometry In The  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to:46 -Energieprojekte GmbHMilo, Maine:Energy Information23.Energy DemandSalton Sea

329

E-Print Network 3.0 - andstrongly deformed structure Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

andstrongly deformed structure Search Powered by Explorit Topic List Advanced Search Sample search results for: andstrongly deformed structure Page: << < 1 2 3 4 5 > >> 1 Equation...

330

EFFECT OF GRAIN SIZE ON THE ACOUSTIC EMISSION GENERATED DURING PLASTIC DEFORMATION OF ALUMINUM  

E-Print Network [OSTI]

PLASTIC DEFORMATION OF ALUMINUM LAWRENCE BERKELEY LABORATORYDURING PLASTIC DEFORMATION OF ALUMINUM J. Baram Materialsof polycrystalline aluminum, of different grain sizes and at

Baram, J.

2013-01-01T23:59:59.000Z

331

EFFECT OF GRAIN SIZE ON THE ACOUSTIC EMISSION GENERATED DURING PLASTIC DEFORMATION OF COPPER  

E-Print Network [OSTI]

PLASTIC DEFORMATION OF COPPER J, Baram Materials Engineeringfrom plastically deformed copper specimens were analyzedrelated to the behavior of copper while undergoing plastic

Baram, J.

2011-01-01T23:59:59.000Z

332

E-Print Network 3.0 - aligned breakup deformation Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

drop deformation and breakup within time... .g., oil-in-water, polymer blends, biological fluids by causing deformation ... Source: Cristini, Vittorio - Departments of Biomedical...

333

Neutrinoless double beta decay of $^{150}$Nd with account for deformation  

E-Print Network [OSTI]

A microscopic state-of-the-art calculation of the nuclear matrix element for neutrinoless double beta decay of $^{150}$Nd with an account for nuclear deformation is performed. The proton-neutron quasiparticle random phase approximation (QRPA) with a realistic residual interaction [the Brueckner $G$ matrix derived from the charge-depending Bonn (Bonn-CD) nucleon-nucleon potential] is used as the underlying nuclear structure model. The present calculated matrix element is suppressed by about 40% as compared with our previous QRPA result for $^{150}$Nd obtained with neglect of deformation. By making use of this newest nuclear matrix element, one may conclude that neutrinoless double beta decay of $^{150}$Nd, to be measured soon by the SNO+ collaboration, provides one of the best probes of the Majorana neutrino mass.

Dong-Liang Fang; Amand Faessler; Vadim Rodin; Fedor Simkovic

2010-11-02T23:59:59.000Z

334

Neutrinoless double-{beta} decay of {sup 150}Nd accounting for deformation  

SciTech Connect (OSTI)

A microscopic state-of-the-art calculation of the nuclear matrix element for neutrinoless double-{beta} decay of {sup 150}Nd with an account for nuclear deformation is performed. The proton-neutron quasiparticle random phase approximation (QRPA) with a realistic residual interaction [the Brueckner G matrix derived from the charge-dependent Bonn (Bonn-CD) nucleon-nucleon potential] is used as the underlying nuclear structure model. The present calculated matrix element is suppressed by about 40% as compared with our previous QRPA result for {sup 150}Nd obtained with neglect of deformation. By making use of this newest nuclear matrix element, one may conclude that neutrinoless double-{beta} decay of {sup 150}Nd, to be measured soon by the SNO+ collaboration, provides one of the best probes of the Majorana neutrino mass.

Fang Dongliang; Faessler, Amand; Rodin, Vadim; Simkovic, Fedor [Institut fuer Theoretische Physik, Universitaet Tuebingen, D-72076 Tuebingen (Germany); BLTP, JINR, Dubna (Russian Federation) and Department of Nuclear Physics, Comenius University, SK-842 15 Bratislava (Slovakia)

2010-11-15T23:59:59.000Z

335

Deformation twinning mechanisms in FCC and HCP metals  

SciTech Connect (OSTI)

We report the recent work on twinning and detwinning in fcc and hcp metals based on the in situ and ex situ TEM observations and molecular dynamics simulations. Three aspects are discussed in this paper. (1) Detwinning in single-phase Cu with respect to growth twins, (2) deformation twinning in Ag-Cu composites, and (3) deformation twinning mechanisms in hcp metals. The main conclusion is that atomic structures of interfaces (twin boundaries, two-phases interface, and grain boundaries) play a crucial role in nucleating and propagating of deformation twins.

Wang, Jian [Los Alamos National Laboratory; Tome, Carlos N [Los Alamos National Laboratory; Beyerlein, Irene J [Los Alamos National Laboratory; Misra, Amit [Los Alamos National Laboratory; Mara, N [Los Alamos National Laboratory

2011-01-31T23:59:59.000Z

336

Asphalt Pavement Aging and Temperature Dependent Properties through a Functionally Graded Viscoelastic Model, Part-II: Applications  

E-Print Network [OSTI]

products obtained through fractional distillation of crude oil or petroleum. Due to its organic nature

Paulino, Glaucio H.

337

{alpha}-decay spectroscopy of deformed nuclei reexamined  

SciTech Connect (OSTI)

We perform an extensive analysis of {alpha}-decays to 2{sup +} and 4{sup +} states in deformed even-even nuclei by using the stationary coupled channels approach. Collective excitations are described within the rigid rotor model. The {alpha}-nucleus interaction is given by a double folding procedure with M3Y plus Coulomb nucleon-nucleon forces. We use a repulsive potential with one independent parameter in order to localize the {alpha}-particle on the nuclear surface and to fit the experimental Q-value. The decaying state is identified with the first resonance inside the resulting pocket-like potential, as suggested by microscopic calculations. We obtain a good agreement with existing experimental data concerning decay widths to J=2{sup +},4{sup +} states. The total {alpha}-decay half-lives agrees very well with experimental values by fitting the spectroscopic factor in terms of charge and neutron numbers separately for Z<82 and Z>82. We give predictions for intensities and hindrance factors for 52 even-even {alpha}-emitters with {beta}{sub 2}>0.15 and E{sub 2{sup +}}<200 kev. Comparison between the phenomenological and microscopic spectroscopic factors revealed large {alpha}-clustering components for nuclei close and above N=82,Z=82,N=126 magic numbers.

Peltonen, S.; Suhonen, J. [Department of Physics, University of Jyvaeskylae, POB 35, FIN-40351, Jyvaeskylae (Finland); Delion, D. S. [National Institute of Physics and Nuclear Engineering, Atomistilor 407, Bucharest-Magurele, 077125 (Romania); Academy of Romanian Scientists, 54 Splaiul Independentei, Bucharest, 050085 (Romania)

2008-09-15T23:59:59.000Z

338

Symmetry energy of deformed neutron-rich nuclei  

E-Print Network [OSTI]

The symmetry energy, the neutron pressure and the asymmetric compressibility of deformed neutron-rich even-even nuclei are calculated on the examples of Kr and Sm isotopes within the coherent density fluctuation model using the symmetry energy as a function of density within the Brueckner energy-density functional. The correlation between the thickness of the neutron skin and the characteristics related with the density dependence of the nuclear symmetry energy is investigated for isotopic chains of these nuclei in the framework of the self-consistent Skyrme-Hartree-Fock plus BCS method. Results for an extended chain of Pb isotopes are also presented. A remarkable difference is found in the trend followed by the different isotopic chains: the studied correlations reveal a smoother behavior in the Pb case than in the other cases. We also notice that the neutron skin thickness obtained for $^{208}$Pb with SLy4 force is found to be in a good agreement with recent data.

Gaidarov, M K; Sarriguren, P; de Guerra, E Moya

2012-01-01T23:59:59.000Z

339

EXISTENCE OF SOLUTIONS TO A NONLINEAR PROBLEM INVOLVING ISOTROPIC DEFORMATIONS  

E-Print Network [OSTI]

EXISTENCE OF SOLUTIONS TO A NONLINEAR PROBLEM INVOLVING ISOTROPIC DEFORMATIONS ANA CRISTINA BARROSO manuscript, published in "Journal of Nonlinear Systems and Applications (2010) ?" #12;2 ANA CRISTINA BARROSO

Paris-Sud XI, Université de

340

3D deformation field throughout the interior of materials.  

SciTech Connect (OSTI)

This report contains the one-year feasibility study for our three-year LDRD proposal that is aimed to develop an experimental technique to measure the 3D deformation fields inside a material body. In this feasibility study, we first apply Digital Volume Correlation (DVC) algorithm to pre-existing in-situ Xray Computed Tomography (XCT) image sets with pure rigid body translation. The calculated displacement field has very large random errors and low precision that are unacceptable. Then we enhance these tomography images by setting threshold of the intensity of each slice. DVC algorithm is able to obtain accurate deformation fields from these enhanced image sets and the deformation fields are consistent with the global mechanical loading that is applied to the specimen. Through this study, we prove that the internal markers inside the pre-existing tomography images of aluminum alloy can be enhanced and are suitable for DVC to calculate the deformation field throughout the material body.

Jin, Huiqing; Lu, Wei-Yang

2013-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Mineral Deformation at Earth's Core-Mantle Boundary  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Deformation at Earth's Core-Mantle Boundary Print Wednesday, 31 August 2011 00:00 Earth is a dynamic planet in which convection takes place on the scale of thousands of...

342

Fabrication of amorphous metal matrix composites by severe plastic deformation  

E-Print Network [OSTI]

Bulk metallic glasses (BMGs) have displayed impressive mechanical properties, but the use and dimensions of material have been limited due to critical cooling rate requirements and low ductility. The application of severe plastic deformation...

Mathaudhu, Suveen Nigel

2006-10-30T23:59:59.000Z

343

anomalously large deformation: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

radiation. I. F. Malov 2007-11-04 88 A study of large plastic deformations in dual phase steel using digital image correlation and FE analysis Physics Websites Summary: ),...

344

Activation of conductive pathways via deformation-induced instabilities  

E-Print Network [OSTI]

Inspired by the pattern transformation of periodic elastomeric cellular structures, the purpose of this work is to exploit this unique ability to activate conductive via deformation-induced instabilities. Two microstructural ...

Ni, Xinchen

2014-01-01T23:59:59.000Z

345

DEFORMATION-BASED NONLINEAR DIMENSION REDUCTION: APPLICATIONS TO NUCLEAR MORPHOMETRY  

E-Print Network [OSTI]

DEFORMATION-BASED NONLINEAR DIMENSION REDUCTION: APPLICATIONS TO NUCLEAR MORPHOMETRY Gustavo K, contrary to common intuition, the most likely nuclear shape configuration is not symmetric. Index Terms-- Nuclear shape analysis, nonlinear, dimension reduction, image registration. 1. INTRODUCTION Under

Gordon, Geoffrey J.

346

Graded Materials for Resistance to Contact Deformation and Damage  

E-Print Network [OSTI]

Graded Materials for Resistance to Contact Deformation and Damage S. Suresh The mechanical response as diverse as tribology, geology, optoelectronics, biomechanics, fracture mechanics, and nanotechnology changes in the elastic properties of sands, soils, and rocks beneath Earth's surface in- fluence

Suresh, Subra

347

Experimental Study on Rock Deformation and Permeability Variation  

E-Print Network [OSTI]

The development of a petroleum reservoir would inevitably induce a rearrangement of the in-situ stress field. The rearrangement of the stress field would then bring about a deformation of the reservoir rock and a change of the permeability...

Ding, Jihui

2013-08-01T23:59:59.000Z

348

Self-sorting of deformable particles in a microfluidic circuit  

E-Print Network [OSTI]

In this thesis, a new microfluidic device is presented for sorting of deformable particles based on the hydrodynamic resistance induced in a microchannel. Hydrodynamic resistance can be related to physical properties, ...

Raafat, Mohamed Salem

2010-01-01T23:59:59.000Z

349

antebrachial growth deformity: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

boost generator as the corner transfer matrix is briefly discussed. Cesar Gomez; Rafael Hernandez 2007-03-23 35 Deformation in Phase Space Mathematical Physics (arXiv) Summary:...

350

TDHF fusion calculations for spherical+deformed systems  

E-Print Network [OSTI]

We outline a formalism to carry out TDHF calculations of fusion cross sections for spherical + deformed nuclei. The procedure incorporates the dynamic alignment of the deformed nucleus into the calculation of the fusion cross section. The alignment results from multiple E2/E4 Coulomb excitation of the ground state rotational band. Implications for TDHF fusion calculations are discussed. TDHF calculations are done in an unrestricted three-dimensional geometry using modern Skyrme force parametrizations.

A. S. Umar; V. E. Oberacker

2006-04-04T23:59:59.000Z

351

Deformed Kazhdan-Lusztig elements and Macdonald polynomials  

E-Print Network [OSTI]

We introduce deformations of Kazhdan-Lusztig elements and specialised nonsymmetric Macdonald polynomials, both of which form a distinguished basis of the polynomial representation of a maximal parabolic subalgebra of the Hecke algebra. We give explicit integral formula for these polynomials, and explicitly describe the transition matrices between classes of polynomials. We further develop a combinatorial interpretation of homogeneous evaluations using an expansion in terms of Schubert polynomials in the deformation parameters.

Jan de Gier; Alain Lascoux; Mark Sorrell

2011-06-06T23:59:59.000Z

352

Experimental deformation of multilithologic specimens simulating sedimentary facies changes  

E-Print Network [OSTI]

EXPERIMENTAL DEFORMATION OF MULTILITHOLOGIC SPECIMENS SIMULATING SEDIMENTARY FACIES CHANGES A Thesis by LAWRENCE DANA DYKE Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE December 1976 Major Subject: Geology EXPERIMENTAL DEFORMATION OF MULTILITHOLOGIC SPECIMENS SIMULATING SEDIMENTARY FACIES CHANGES A Thesis by LAWRENCE DANA DYKE Approved as to style and content by: (Chai n Committee) (Head...

Dyke, Lawrence Dana

1976-01-01T23:59:59.000Z

353

Effect of nuclear deformation on double beta decay  

SciTech Connect (OSTI)

The existing ways of accounting for deformation in recent calculations of neutrinoless double beta decay matrix elements are discussed. From an analysis of relevant experimental data it is argued that only {sup 150}Nd reveals convincing evidences of strong static deformation, which should eventually be taken into account in QRPA calculations. A proposal which allows in principle to measure the neutrino less double beta decay Fermi matrix element is briefly described.

Rodin, Vadim [Institute fuer Theoretische Physik der Universitaet Tuebingen, D-72076 Tuebingen (Germany)

2009-11-09T23:59:59.000Z

354

N=4 Scattering Amplitudes and the Deformed Grassmannian  

E-Print Network [OSTI]

Some time ago the general tree-level scattering amplitudes of N=4 Super Yang-Mills theory were expressed as certain Grassmannian contour integrals. These remarkable formulas allow to clearly expose the super-conformal, dual super-conformal, and Yangian symmetries of the amplitudes. Using ideas from integrability it was recently shown that the building blocks of the amplitudes permit a natural multi-parameter deformation. However, this approach had been criticized by the observation that it seemed impossible to reassemble the building blocks into Yangian-invariant deformed non-MHV amplitudes. In this note we demonstrate that the deformations may be succinctly summarized by a simple modification of the measure of the Grassmannian integrals, leading to a Yangian-invariant deformation of the general tree-level amplitudes. Interestingly, the deformed building-blocks appear as residues of poles in the spectral parameter planes. Given that the contour integrals also contain information on the amplitudes at loop-level, we expect the deformations to be useful there as well. In particular, applying meromorphicity arguments, they may be expected to regulate all notorious infrared divergences. We also point out relations to Gelfand hypergeometric functions and the quantum Knizhnik-Zamolodchikov equations.

Livia Ferro; Tomasz Lukowski; Matthias Staudacher

2014-07-24T23:59:59.000Z

355

Numerical study of viscoelastic mixtures through a Cahn-Hilliard Franck Boyer1  

E-Print Network [OSTI]

-time numerical simulations. Several significant tests (channel under shear, filling of tanks, breakup of jets. In this model, the sharp interface is replaced by a narrow transition layer across which the fluids may mix to describe the concentration of one of the fluids in the mixture. The resulting system of equations couples

Paris-Sud XI, Université de

356

Size effects on the onset of plastic deformation during nanoindentation of thin films and patterned lines  

E-Print Network [OSTI]

Size effects on the onset of plastic deformation during nanoindentation of thin films and patterned; accepted 13 August 2003 Plastic deformation of materials exhibits a strong size dependence when, particularly the transition from elastic to plastic deformation and the early stages of plastic deformation. We

Van Vliet, Krystyn J.

357

Mass-Conserved Phase Field Models for Binary Fluids  

E-Print Network [OSTI]

Recently, phase field models are applied. 27 to study liquid crystal drop deformation in another fluid, liquid films, polymer nanocom-. 28 posites, and biofilms [5, ...

2012-07-13T23:59:59.000Z

358

Numerical Modeling of Fracture Permeability Change in Naturally Fractured Reservoirs Using a Fully Coupled Displacement Discontinuity Method.  

E-Print Network [OSTI]

finite difference method to solve the fluid flow in fractures, a fully coupled displacement discontinuity method to build the global relation of fracture deformation, and the Barton-Bandis model of fracture deformation to build the local relation...

Tao, Qingfeng

2010-07-14T23:59:59.000Z

359

Internal solitary waves: propagation, deformation and disintegration  

E-Print Network [OSTI]

model equation is the variable-coefficient KdV equation At + cAx - cQx Q A + µAAx + Axxx = 0 , (1) Here

360

Hydrothermal Systems Rock Deformation and Geodynamics  

E-Print Network [OSTI]

Update Seminar Process Modelling of Hydrothermal Systems using SHEMAT / Processing SHEMAT 20 - 22 August to develop a process understanding of reactive transport in hydrothermal systems and to make responsible.rwth-academy.com/geophysics.html With contributions from #12;Process Modelling of Hydrothermal Systems using SHEMAT / Processing SHEMAT Hydrothermal

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Permeation of low-Z atoms through carbon sheets: Density functional theory study on energy barriers and deformation effects  

SciTech Connect (OSTI)

Energetic and geometric aspects of the permeation of the atoms hydrogen to neon neutral atoms through graphene sheets are investigated by investigating the associated energy barriers and sheet deformations. Density functional theory calculations on cluster models, where graphene is modeled by planar polycyclic aromatic hydrocarbons (PAHs), provide the energies and geometries. Particularities of our systems, such as convergence of both energy barriers and deformation curves with increasing size of the PAHs, are discussed. Three different interaction regimes, adiabatic, planar and vertical, are investigated by enforcing different geometrical constraints. The adiabatic energy barriers range from 5 eV for hydrogen to 20 eV for neon. We find that the permeation of oxygen and carbon into graphene is facilitated by temporary chemical bonding while for other, in principle reactive atoms, it is not. We discuss implications of our results for modeling chemical sputtering of graphite.

Huber, Stefan E., E-mail: s.huber@uibk.ac.at, E-mail: Michael.probst@uibk.ac.at; Mauracher, Andreas; Probst, Michael, E-mail: s.huber@uibk.ac.at, E-mail: Michael.probst@uibk.ac.at [Institute of Ion Physics and Applied Physics, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck (Austria)] [Institute of Ion Physics and Applied Physics, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck (Austria)

2013-12-15T23:59:59.000Z

362

A versatile facility for laboratory studies of viscoelastic and poroelastic behaviour of rocks  

SciTech Connect (OSTI)

Novel laboratory equipment has been modified to allow both torsional and flexural oscillation measurements at sub-microstrain amplitudes, thereby providing seismic-frequency constraints on both the shear and compressional wave properties of cylindrical rock specimens within the linear regime. The new flexural mode capability has been tested on experimental assemblies containing fused silica control specimens. Close consistency between the experimental data and the results of numerical modelling with both finite-difference and finite-element methods demonstrates the viability of the new technique. The capability to perform such measurements under conditions of independently controlled confining and pore-fluid pressure, with emerging strategies for distinguishing between local (squirt) and global (specimen-wide) fluid flow, will have particular application to the study of frequency-dependent seismic properties expected of cracked and fluid-saturated rocks of the Earth's upper crust.

Jackson, Ian [Research School of Earth Sciences, Australian National University, Canberra ACT 0200 (Australia); Schijns, Heather; Schmitt, Douglas R. [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Mu Junjie; Delmenico, Alison [Department of Engineering, Australian National University, Canberra ACT 0200 (Australia)

2011-06-15T23:59:59.000Z

363

Temperature dependent deformation mechanisms in pure amorphous silicon  

SciTech Connect (OSTI)

High temperature nanoindentation has been performed on pure ion-implanted amorphous silicon (unrelaxed a-Si) and structurally relaxed a-Si to investigate the temperature dependence of mechanical deformation, including pressure-induced phase transformations. Along with the indentation load-depth curves, ex situ measurements such as Raman micro-spectroscopy and cross-sectional transmission electron microscopy analysis on the residual indents reveal the mode of deformation under the indenter. While unrelaxed a-Si deforms entirely via plastic flow up to 200?°C, a clear transition in the mode of deformation is observed in relaxed a-Si with increasing temperature. Up to 100?°C, pressure-induced phase transformation and the observation of either crystalline (r8/bc8) end phases or pressure-induced a-Si occurs in relaxed a-Si. However, with further increase of temperature, plastic flow rather than phase transformation is the dominant mode of deformation. It is believed that the elevated temperature and pressure together induce bond softening and “defect” formation in structurally relaxed a-Si, leading to the inhibition of phase transformation due to pressure-releasing plastic flow under the indenter.

Kiran, M. S. R. N., E-mail: kiran.mangalampalli@anu.edu.au; Haberl, B.; Williams, J. S.; Bradby, J. E. [Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia)

2014-03-21T23:59:59.000Z

364

Determination of the effective stress law for permeability and deformation in low-permeability rocks  

SciTech Connect (OSTI)

This paper reports that laboratory experiments were performed to determine the effective stress law of tight sandstones and chalk for permeability and deformation. Permeability and volumetric strain data were taken at various stresses and pore pressures and were analyzed with a statistical model-building approach. Results show that the effective stress laws for both processes are variable with stress and pressure, depend on the material, and do not agree well with present theories. This may be applied for a greater understanding of oil reservoir formations.

Warpinski, N.R.; Teufel, L.W. (Sandia National Lab. (US))

1992-06-01T23:59:59.000Z

365

Modelling of friction stir welding  

E-Print Network [OSTI]

This thesis investigates the modelling of friction stir welding (FSW). FSW is a relatively new welding process where a rotating non-consumable tool is used to join two materials through high temperature deformation. The aim of the thesis...

Colegrove, Paul Andrew

366

Microstructure, strengthening mechanisms and hot deformation behavior of an oxide-dispersion strengthened UFG Al6063 alloy  

SciTech Connect (OSTI)

An ultrafine-grained Al6063/Al{sub 2}O{sub 3} (0.8 vol.%, 25 nm) nanocomposite was prepared via powder metallurgy route through reactive mechanical alloying and hot powder extrusion. Scanning electron microcopy, transmission electron microscopy, and back scattered electron diffraction analysis showed that the grain structure of the nanocomposite is trimodal and composed of nano-size grains (< 0.1 {mu}m), ultrafine grains (0.1-1 {mu}m), and micron-size grains (> 1 {mu}m) with random orientations. Evaluation of the mechanical properties of the nanocomposite based on the strengthening-mechanism models revealed that the yield strength of the ultrafine-grained nanocomposite is mainly controlled by the high-angle grain boundaries rather than nanometric alumina particles. Hot deformation behavior of the material at different temperatures and strain rates was studied by compression test and compared to coarse-grained Al6063 alloy. The activation energy of the hot deformation process for the nanocomposite was determined to be 291 kJ mol{sup -1}, which is about 64% higher than that of the coarse-grained alloy. Detailed microstructural analysis revealed that dynamic recrystallization is responsible for the observed deformation softening in the ultrafine-grained nanocomposite. - Highlights: Black-Right-Pointing-Pointer The strengthening mechanisms of Al6063/Al{sub 2}O{sub 3} nanocomposite were evaluated. Black-Right-Pointing-Pointer Hot deformation behavior of the nanocomposite was studied. Black-Right-Pointing-Pointer The hot deformation activation energy was determined using consecutive models. Black-Right-Pointing-Pointer The restoration mechanisms and microstructural changes are presented.

Asgharzadeh, H. [Department of Mechanical Engineering, University of Tabriz, P.O. Box 51666-16471, Tabriz (Iran, Islamic Republic of)] [Department of Mechanical Engineering, University of Tabriz, P.O. Box 51666-16471, Tabriz (Iran, Islamic Republic of); Kim, H.S. [Department of Materials Science and Engineering, Pohang University of Science and Technology, P.O. Box 790-784, Pohang (Korea, Republic of)] [Department of Materials Science and Engineering, Pohang University of Science and Technology, P.O. Box 790-784, Pohang (Korea, Republic of); Simchi, A., E-mail: simchi@sharif.edu [Department of Materials Science and Engineering and Institute for Nanoscience and Nanotechnology, Sharif University of Technology, P.O. Box 11365-9466, Tehran (Iran, Islamic Republic of)

2013-01-15T23:59:59.000Z

367

Kinematic quantities of finite elastic and plastic deformation  

E-Print Network [OSTI]

Kinematic quantities for finite elastic and plastic deformations are defined via an approach that does not rely on auxiliary elements like reference frame and reference configuration, and that gives account of the inertial-noninertial aspects explicitly. These features are achieved by working on Galilean spacetime directly. The quantity expressing elastic deformations is introduced according to its expected role: to measure how different the current metric is from the relaxed/stressless metric. Further, the plastic kinematic quantity is the change rate of the stressless metric. The properties of both are analyzed, and their relationship to frequently used elastic and plastic kinematic quantities is discussed. One important result is that no objective elastic or plastic quantities can be defined from deformation gradient.

T. Fülöp; P. Ván

2012-03-05T23:59:59.000Z

368

Nuclear skin emergence in Skyrme deformed Hartree-Fock calculations  

E-Print Network [OSTI]

A study of the charge and matter densities and the corresponding rms radii for even-even isotopes of Ni, Kr, and Sn has been performed in the framework of deformed self-consistent mean field Skyrme HF+BCS method. The resulting charge radii and neutron skin thicknesses of these nuclei are compared with available experimental data, as well as with other theoretical predictions. The formation of a neutron skin, which manifests itself in an excess of neutrons at distances greater than the radius of the proton distribution, is analyzed in terms of various definitions. Formation of a proton skin is shown to be unlikely. The effects of deformation on the neutron skins in even-even deformed nuclei far from the stability line are discussed.

Sarriguren, P; de Guerra, E Moya; Antonov, A N

2007-01-01T23:59:59.000Z

369

Influence of ensemble boundary conditions (thermostat and barostat) on the deformation of amorphous polyethylene by molecular dynamics  

E-Print Network [OSTI]

Molecular dynamics simulations are increasingly being used to investigate the structural evolution of polymers during mechanical deformation, but relatively few studies focus on the influence of boundary conditions on this evolution, in particular the dissipation of both heat and pressure through the periodic boundaries during deformation. The research herein explores how the tensile deformation of amorphous polyethylene, modelled with a united atom method potential, is influenced by heat and pressure dissipation. The stress-strain curves for the pressure dissipation cases (uniaxial tension) are in qualitative agreement with experiments and show that heat dissipation has a large effect on the strain hardening modulus calculated by molecular dynamics simulations. The evolution of the energy associated with bonded and non-bonded terms was quantified as a function of strain as well as the evolution of stress in both the loading and non-loading directions to give insight into how the stress state is altered within the elastic, yield, strain softening, and strain hardening regions. The stress partitioning shows a competition between `tensile' Van der Waal's interactions and `compressive' bond stretching forces, with the characteristic yield stress peak clearly associated with the non-bonded stress. The lack of heat dissipation had the largest effect on the strain hardening regime, where an increase in the calculated temperature correlated with faster chain alignment in the loading direction and more rapid conformation changes. In part, these observations demonstrate the role that heat and pressure dissipation play on deformation characteristics of amorphous polymers, particularly for the strain hardening regime.

M. A. Tschopp; J. L. Bouvard; D. K. Ward; D. J. Bammann; M. F. Horstemeyer

2013-10-02T23:59:59.000Z

370

JOURNAL OF MATERIALS SCIENCE 2012, IN PRESS DOI: 10.1007/S10853-012-6927-8 Viscoelastic properties of hollow glass particle filled vinyl ester matrix syntactic foams: effect of temperature and loading  

E-Print Network [OSTI]

properties of hollow glass particle filled vinyl ester matrix syntactic foams: effect of temperature compositions of syntactic foams. Storage modulus, loss modulus, and glass transition temperature (Tg@poly.edu Abstract Viscoelastic properties of hollow particle reinforced composites called syntactic foams

Gupta, Nikhil

371

Motion-Induced Radiation from a Dynamically Deforming Mirror  

E-Print Network [OSTI]

A path integral formulation is developed to study the spectrum of radiation from a perfectly reflecting (conducting) surface. It allows us to study arbitrary deformations in space and time. The spectrum is calculated to second order in the height function. For a harmonic traveling wave on the surface, we find many different regimes in which the radiation is restricted to certain directions. It is shown that high frequency photons are emitted in a beam with relatively low angular dispersion whose direction can be controlled by the mechanical deformations of the plate.

Faez Miri; Ramin Golestanian

1998-03-25T23:59:59.000Z

372

Thermodynamics of a photon gas and deformed dispersion relations  

E-Print Network [OSTI]

We resort to the methods of statistical mechanics in order to determine the effects that a deformed dispersion relation has upon the thermodynamics of a photon gas. The ensuing modifications to the density of states, partition function, pressure, internal energy, entropy, and specific heat are calculated. It will be shown that the breakdown of Lorentz invariance can be interpreted as a repulsive interaction, among the photons. Additionally, it will be proved that the presence of a deformed dispersion relation entails an increase in the entropy of the system. In other words, as a consequence of the loss of the aforementioned symmetry the number of microstates available to the corresponding equilibrium state grows.

A. Camacho; A. Macias

2007-02-28T23:59:59.000Z

373

A microscopic view of accelerated dynamics in deformed polymer glasses  

E-Print Network [OSTI]

A molecular level analysis of segmental trajectories obtained from molecular dynamics simulations is used to obtain the full relaxation time spectrum in aging polymer glasses subject to three different deformation protocols. As in experiments, dynamics can be accelerated by several orders of magnitude, and a narrowing of the distribution of relaxation times during creep is directly observed. Additionally, the acceleration factor describing the transformation of the relaxation time distributions is computed and found to obey a universal dependence on the global strain, independent of age and deformation protocol.

Mya Warren; Joerg Rottler

2010-02-09T23:59:59.000Z

374

Microscopic and self-consistent description for neutron halo in deformed nuclei  

SciTech Connect (OSTI)

A deformed relativistic Hartree-Bogoliubov theory in continuum has been developed for the study of neutron halos in deformed nuclei and the halo phenomenon in deformed weakly bound nuclei is investigated. Magnesium and neon isotopes are studied and some results are presented for the deformed neutron-rich and weakly bound nuclei {sup 44}Mg and {sup 36}Ne. The core of the former nucleus is prolate, but the halo has a slightly oblate shape. This indicates a decoupling of the halo orbitals from the deformation of the core. The generic conditions for the existence of halos in deformed nuclei and for the occurrence of this decoupling effect are discussed.

Li Lulu [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Meng Jie [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China) and Department of Physics, University of Stellenbosch, Stellenbosch (South Africa); Zhao Enguang; Zhou Shangui [State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190 (China) and Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000 (China)

2013-05-06T23:59:59.000Z

375

Modeling and Algorithmic Approaches to Constitutively-Complex, Microstructured Fluids  

SciTech Connect (OSTI)

We present a new multiscale model for complex uids based on three scales: microscopic, kinetic, and continuum. We choose the microscopic level as Kramers' bead-rod model for polymers, which we describe as a system of stochastic di#11;erential equations with an implicit constraint formulation. The associated Fokker-Planck equation is then derived, and adiabatic elimination removes the fast momentum coordinates. Approached in this way, the kinetic level reduces to a dispersive drift equation. The continuum level is modeled with a #12;nite volume Godunov-projection algorithm. We demonstrate computation of viscoelastic stress divergence using this multiscale approach.

Miller, Gregory H.; Forest, Gregory

2011-12-22T23:59:59.000Z

376

A three-parametric deformation of GL(1/1)  

E-Print Network [OSTI]

A three-parametric $R$-matrix satisfying a graded Yang-Baxter equation is introduced.This $R$-matrix allows us to construct new quantum supergroups which are deformations of the supergroup $GL(1/1)$ and the universal enveloping algebra $U[gl(1/1)]$.

Nguyen Anh Ky; Nguyen Thi Hong Van

2005-10-11T23:59:59.000Z

377

Qubit dynamics in a q-deformed oscillators environment  

E-Print Network [OSTI]

We study the dynamics of one and two qubits plunged in a q-deformed oscillators environment. Specifically we evaluate the decay of quantum coherence and entanglement in time when passing from bosonic to fermionic environments. Slowing down of decoherence in the fermionic case is found. The effect only manifests at finite temperature.

S. L'Innocente; C. Lupo; S. Mancini

2009-12-19T23:59:59.000Z

378

Deformation and $?$ clustering in excited states of $^{42}$Ca  

E-Print Network [OSTI]

The coexistence of various low-lying deformed states in $^{42}$Ca and $\\alpha$--$^{38}$Ar correlations in those deformed states have been investigated using deformed-basis antisymmetrized molecular dynamics. Wave functions of the low-lying states are obtained via parity and angular momentum projections and the generator coordinate method (GCM). Basis wave functions of the GCM calculation are obtained via energy variations with constraints on the quadrupole deformation parameter $\\beta$ and the distance between $\\alpha$ and $^{38}$Ar clusters. The rotational band built on the $J^\\pi = 0_2^+$ (1.84 MeV) state as well as the $J^\\pi = 0_3^+$ (3.30 MeV) state are both reproduced. The coexistence of two additional $K^\\pi = 0^+$ rotational bands is predicted; one band is shown to be built on the $J^\\pi = 0_3^+$ state. Members of the ground-state band and the rotational band built on the $J^\\pi = 0_3^+$ state contain $\\alpha$--$^{38}$Ar cluster structure components.

Yasutaka Taniguchi

2014-04-09T23:59:59.000Z

379

Experimental validation of finite element codes for welding deformations  

E-Print Network [OSTI]

Experimental validation of finite element codes for welding deformations H. M. Aarbogha,b, , M Institute for Energy Technology, N-2027 Kjeller, Norway. Abstract A single pass Metal Inert Gas welding which numerical codes quantifying welding stresses can be validated. It includes a mov- ing heat source

Boyer, Edmond

380

Master Thesis: Simulation of plastic deformation in cemented carbide inserts  

E-Print Network [OSTI]

Master Thesis: Simulation of plastic deformation in cemented carbide inserts Background Sandvik in cemented carbide, high-speed steel and other hard materials such as diamond, cubic boron nitride in cemented carbide inserts will be performed using the FEM software Ansys and AdvantEdge. The work

Haviland, David

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381

CONTAINED PLASTIC DEFORMATION NEAR CRACKS AND NOTCHES UNDER LONGITUDINAL SHEAR  

E-Print Network [OSTI]

CONTAINED PLASTIC DEFORMATION NEAR CRACKS AND NOTCHES UNDER LONGITUDINAL SHEAR James R. Rice* ABSTRACT An exact linear elastic-perfectly plastic solution is presented for the problem of a sharp notch coordinates corresponding to given stresses, position of the elastic-plastic boundary, and accompanying

382

Labeling the Brain Surface Using a Deformable Multiresolution Mesh  

E-Print Network [OSTI]

Labeling the Brain Surface Using a Deformable Multiresolution Mesh Sylvain Jaume1 , Beno^it Macq2 Abstract. We propose to match a labeled mesh onto the patient brain surface in a multiresolution way for labeling the patient brain. Labeling the patient brain surface provides a map of the brain folds where

Desbrun, Mathieu

383

Mechanical deformations of boron nitride nanotubes in crossed junctions  

SciTech Connect (OSTI)

We present a study of the mechanical deformations of boron nitride nanotubes (BNNTs) in crossed junctions. The structure and deformation of the crossed tubes in the junction are characterized by using atomic force microscopy. Our results show that the total tube heights are reduced by 20%–33% at the crossed junctions formed by double-walled BNNTs with outer diameters in the range of 2.21–4.67?nm. The measured tube height reduction is found to be in a nearly linear relationship with the summation of the outer diameters of the two tubes forming the junction. The contact force between the two tubes in the junction is estimated based on contact mechanics theories and found to be within the range of 4.2–7.6 nN. The Young's modulus of BNNTs and their binding strengths with the substrate are quantified, based on the deformation profile of the upper tube in the junction, and are found to be 1.07?±?0.11 TPa and 0.18–0.29 nJ/m, respectively. Finally, we perform finite element simulations on the mechanical deformations of the crossed BNNT junctions. The numerical simulation results are consistent with both the experimental measurements and the analytical analysis. The results reported in this paper contribute to a better understanding of the structural and mechanical properties of BNNTs and to the pursuit of their applications.

Zhao, Yadong; Chen, Xiaoming; Ke, Changhong, E-mail: cke@binghamton.edu [Department of Mechanical Engineering, State University of New York at Binghamton, Binghamton, New York 13902 (United States); Park, Cheol [NASA Langley Research Center, Hampton, Virginia 23681 (United States); Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Fay, Catharine C. [NASA Langley Research Center, Hampton, Virginia 23681 (United States); Stupkiewicz, Stanislaw [Institute of Fundamental Technological Research, Warsaw (Poland)

2014-04-28T23:59:59.000Z

384

TRANSMISSION ELECTRON MICROSCOPY OF WEAKLY DEFORMED ALKALI HALIDE CRYSTALS  

E-Print Network [OSTI]

377 TRANSMISSION ELECTRON MICROSCOPY OF WEAKLY DEFORMED ALKALI HALIDE CRYSTALS H. STRUNK Max'importance croissante du durcissement de la solution solide. Abstract. 2014 Transmission electron microscopy (TEM Abstracts 7j66 - 7 I' 1. Introduction. - It is only some years ago that transmission electron microscopy

Boyer, Edmond

385

Large Deformation Constitutive Laws for Isotropic Thermoelastic Materials  

SciTech Connect (OSTI)

We examine the approximations made in using Hooke's law as a constitutive relation for an isotropic thermoelastic material subjected to large deformation by calculating the stress evolution equation from the free energy. For a general thermoelastic material, we employ the volume-preserving part of the deformation gradient to facilitate volumetric/shear strain decompositions of the free energy, its first derivatives (the Cauchy stress and entropy), and its second derivatives (the specific heat, Grueneisen tensor, and elasticity tensor). Specializing to isotropic materials, we calculate these constitutive quantities more explicitly. For deformations with limited shear strain, but possibly large changes in volume, we show that the differential equations for the stress components involve new terms in addition to the traditional Hooke's law terms. These new terms are of the same order in the shear strain as the objective derivative terms needed for frame indifference; unless the latter terms are negligible, the former cannot be neglected. We also demonstrate that accounting for the new terms requires that the deformation gradient be included as a field variable

Plohr, Bradley J. [Los Alamos National Laboratory; Plohr, Jeeyeon N. [Los Alamos National Laboratory

2012-07-25T23:59:59.000Z

386

Structural control of elastic moduli in ferrogels and the importance of non-affine deformations  

E-Print Network [OSTI]

One of the central appealing properties of magnetic gels and elastomers is that their elastic moduli can reversibly be adjusted from outside by applying magnetic fields. The impact of the internal magnetic particle distribution on this effect has been outlined and analyzed theoretically. In most cases, however, affine sample deformations are studied and often regular particle arrangements are considered. Here we challenge these two major simplifications by a systematic approach using a minimal dipole-spring model. Starting from different regular lattices, we take into account increasingly randomized structures, until we finally investigate an irregular texture taken from a real experimental sample. On the one hand, we find that the elastic tunability qualitatively depends on the structural properties, here in two spatial dimensions. On the other hand, we demonstrate that the assumption of affine deformations leads to increasingly erroneous results the more realistic the particle distribution becomes. Understanding the consequences of the assumptions made in the modeling process is important on our way to support an improved design of these fascinating materials.

Giorgio Pessot; Peet Cremer; Dmitry Y. Borin; Stefan Odenbach; Hartmut Löwen; Andreas M. Menzel

2014-10-21T23:59:59.000Z

387

Rigid-Plastic Approximations for Predicting Plastic Deformation of Cylindrical Shells Subject to Dynamic Loading  

E-Print Network [OSTI]

A theoretical approach was developed for predicting the plastic deformation of a cylindrical shell subject to asymmetric dynamic loads. The plastic deformation of the leading generator of the shell is found by solving for ...

Hoo Fatt, Michelle S.

388

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation Print Wednesday, 25 November 2009 00:00 Magnetic...

389

Normal and lateral Casimir forces between deformed plates  

SciTech Connect (OSTI)

The Casimir force between macroscopic bodies depends strongly on their shape and orientation. To study this geometry dependence in the case of two deformed metal plates, we use a path-integral quantization of the electromagnetic field which properly treats the many-body nature of the interaction, going beyond the commonly used pairwise summation (PWS) of van der Waals forces. For arbitrary deformations we provide an analytical result for the deformation induced change in the Casimir energy, which is exact to second order in the deformation amplitude. For the specific case of sinusoidally corrugated plates, we calculate both the normal and the lateral Casimir forces. The deformation induced change in the Casimir interaction of a flat and a corrugated plate shows an interesting crossover as a function of the ratio of the mean plate distance H to the corrugation length {lambda}: For {lambda}<>H. The amplitude of the lateral force between two corrugated plates which are out of registry is shown to have a maximum at an optimal wavelength of {lambda}{approx_equal}2.5 H. With increasing H/{lambda} > or approx. 0.3 the PWS approach becomes a progressively worse description of the lateral force due to many-body effects. These results may be of relevance for the design and operation of novel microelectromechanical systems (MEMS) and other nanoscale devices.

Emig, Thorsten; Hanke, Andreas; Golestanian, Ramin; Kardar, Mehran [Institut fuer Theoretische Physik, Universitaet zu Koeln, Zuelpicher Strasse 77, D-50937 Cologne (Germany); Institut fuer Theoretische Physik, Universitaet Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart (Germany); Institute for Advanced Studies in Basic Sciences, Zanjan 45195-159 (Iran, Islamic Republic of); Institute for Studies in Theoretical Physics and Mathematics, P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Physics Department, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2003-02-01T23:59:59.000Z

390

Continuum-kinetic-microscopic model of lung clearance due to core-annular fluid entrainment  

SciTech Connect (OSTI)

The human lung is protected against aspirated infectious and toxic agents by a thin liquid layer lining the interior of the airways. This airway surface liquid is a bilayer composed of a viscoelastic mucus layer supported by a fluid film known as the periciliary liquid. The viscoelastic behavior of the mucus layer is principally due to long-chain polymers known as mucins. The airway surface liquid is cleared from the lung by ciliary transport, surface tension gradients, and airflow shear forces. This work presents a multiscale model of the effect of airflow shear forces, as exerted by tidal breathing and cough, upon clearance. The composition of the mucus layer is complex and variable in time. To avoid the restrictions imposed by adopting a viscoelastic flow model of limited validity, a multiscale computational model is introduced in which the continuum-level properties of the airway surface liquid are determined by microscopic simulation of long-chain polymers. A bridge between microscopic and continuum levels is constructed through a kinetic-level probability density function describing polymer chain configurations. The overall multiscale framework is especially suited to biological problems due to the flexibility afforded in specifying microscopic constituents, and examining the effects of various constituents upon overall mucus transport at the continuum scale.

Mitran, Sorin, E-mail: mitran@unc.edu

2013-07-01T23:59:59.000Z

391

Animating Viscoelastic Fluids  

E-Print Network [OSTI]

An introduction to the conjugate gradient method without theusing the conjugate gradient method best described in [

Goktekin, Tolga Gokce

2011-01-01T23:59:59.000Z

392

Active Perception of Deformable Objects using 3D Cameras Guillem Aleny`a, Francesc Moreno-Noguer, Arnau Ramisa, and Carme Torras  

E-Print Network [OSTI]

: grasping of textiles and plant leaf modelling. I. INTRODUCTION 3D perception of deformable objects using RGB cameras has been one the most studied research fields within com- puter vision. There exist and Innovation under project DPI2008-06022 and MIPRCV Consolider Ingenio CSD2007-00018, and the Catalan Research

Moreno-Noguer, Francesc

393

Early detection of brine and CO2 leakage through abandoned wells using pressure and surface-deformation monitoring data: Concept and  

E-Print Network [OSTI]

and surface-deformation modeling tools to estimate the location and permeability of leaky features by Elsevier Ltd. 1. Introduction The ability to detect CO2 leakage is a key component of risk assessment storage for- mation to shallower groundwater aquifers, ultimately to the atmosphere, through abandoned

Zhou, Quanlin

394

Stroke amplifier for deformable mirrors Robert H. Webb, Marc J. Albanese, Yaopeng Zhou, Thomas Bifano, and  

E-Print Network [OSTI]

Stroke amplifier for deformable mirrors Robert H. Webb, Marc J. Albanese, Yaopeng Zhou, Thomas stroke of a deformable mirror. By arranging for the wavefront to traverse the deformable mirror more than to produce lower- cost mirrors. Unfortunately, most commercial MEMS mirrors have only a limited stroke

395

Features Extraction from Point Clouds for Automated Detection of Deformations on Automotive Body Parts  

E-Print Network [OSTI]

Features Extraction from Point Clouds for Automated Detection of Deformations on Automotive Body with the problem of detecting unwanted deformations on automotive body part in mind, where feature line detection, surface map analysis, deformation detection, pattern recognition, quality control, automotive body parts

Payeur, Pierre

396

Conformal invariance of the planar beta-deformed N=4 SYM theory requires beta real  

E-Print Network [OSTI]

We study the \\cal{N}=1 SU(N) SYM theory which is a marginal deformation of the \\cal{N}=4 theory, with a complex deformation parameter \\beta. We consider the large N limit and study perturbatively the conformal invariance condition. We find that finiteness requires reality of the deformation parameter \\beta.

Federico Elmetti; Andrea Mauri; Silvia Penati; Alberto Santambrogio; Daniela Zanon

2006-06-14T23:59:59.000Z

397

PLASTIC VERSUS ELASTIC DEFORMATION EFFECTS ON MAGNETIC BARKHAUSEN NOISE IN STEEL  

E-Print Network [OSTI]

PLASTIC VERSUS ELASTIC DEFORMATION EFFECTS ON MAGNETIC BARKHAUSEN NOISE IN STEEL C.-G. STEFANITA, D) AbstractÐA study was performed to dierentiate the eects of elastic and plastic deformation on magnetic samples subjected to varying degrees of uniaxial elastic and plastic deformation up to H40% strain

Clapham, Lynann

398

Vug waves: A mechanism for coupled rock deformation and fluid migration  

E-Print Network [OSTI]

Vug waves: A mechanism for coupled rock deformation and fluid migration Jason Phipps Morgan-migration mechanism in which a rock deforms by the movement of a penny-shaped, fluid-filled crack dislocation across, Minneapolis, Minnesota 55455, USA (holtz007@tc.umn.edu) [1] Vug waves are a joint deformation/fluid

Holtzman, Ben

399

ACM Reference Format Weber, O., Gotsman, C. 2010. Controllable Conformal Maps for Shape Deformation and Interpolation.  

E-Print Network [OSTI]

ACM Reference Format Weber, O., Gotsman, C. 2010. Controllable Conformal Maps for Shape Deformation.1145/1778765.1778815 Controllable Conformal Maps for Shape Deformation and Interpolation Ofir Weber Craig Gotsman Technion ­ Israel Institute of Technology weber@cs.technion.ac.il gotsman@cs.technion.ac.il Figure 1: Conformal deformation

Kazhdan, Michael

400

Scale Dependence and Localization of the Deformation of Arctic Sea Ice David Marsan  

E-Print Network [OSTI]

, and internal stress gradients, producing spatial gradients in the ice velocity that we refer to as deformationScale Dependence and Localization of the Deformation of Arctic Sea Ice David Marsan Laboratoire de of Arctic sea ice over a 3-day time period is performed for scales of 10 to 1000 km. The deformation field

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Reaction cross-section calculations using new experimental and theoretical level structure data for deformed nuclei  

SciTech Connect (OSTI)

A technique for modeling quasiparticle excitation energies and rotational parameters in odd-odd deformed nuclei has been used to construct sets of discrete states with energy 0 to 1.5 MeV in /sup 176/Lu and /sup 236/Np. These data were used as part of the input for calculation of isomer production cross-section ratios in the /sup 175/Lu(n,..gamma..)/sup 176/Lu and /sup 237/Np(n,2n)/sup 236/Np reactions. In order to achieve agreement with experiment, it has been found necessary to include in the modeled set many rotational bands (35 to 95), which are comprised of hundreds of levels with their gamma-ray branching ratios. It is essential that enough bands be included to produce a representative selection of K quantum numbers in the de-excitation cascade. 20 refs., 3 figs., 3 tabs.

Hoff, R.W.; Gardner, D.G.; Gardner, M.A.

1984-10-05T23:59:59.000Z

402

Mode I fracture of a biopolymer gel: rate-dependent dissipation and large deformations disentangled  

E-Print Network [OSTI]

We have designed a new experimental setup able to investigate fracture of soft materials at small scales. At high crack velocity, where energy is mostly dissipated through viscoelastic processes, we observe an increasingly large high strain domain in the crack tip vicinity. Taking advantage of our ability to determine where linear elasticity breaks down, we derive a simple prediction for the evolution of the energy release rate with the crack velocity.

Maxime Lefranc; Elisabeth Bouchaud

2015-01-06T23:59:59.000Z

403

Classifying spaces for homogeneous manifolds and their related Lie isometry deformations  

E-Print Network [OSTI]

Among plenty of applications, low-dimensional homogeneous spaces appear in cosmological models as both, classical factor spaces of multidimensional geometry and minisuperspaces in canonical quantization. Here a new tool to restrict their continuous deformations is presented: Classifying spaces for homogeneous manifolds and their related Lie isometry deformations. The adjoint representation of n-dimensional real Lie algebras induces a natural topology on their classifying space, which encodes the natural algebraic relationship between different Lie algebras therein. For n>1 this topology is not Hausdorffian. Even more it satisfies only the separation axiom T_0, but not T_1, i.e. there is a constant sequence which has a limit different from the members of the sequence. Such a limit is called a transition. Recently it was found that transitions are the natural generalization and transitive completion of the well-known In\\"on\\"u-Wigner contractions. For n<5 the relational classifying spaces are constructed explicitly. Calculating their characteristic scalar invariants via triad representations of the characteristic isometry, local homogeneous Riemannian 3-spaces are classified in their natural geometrical relations to each other. Their classifying space is a composition of pieces with different isometry types. Although it is Hausdorffian, different topological transitions to the same limit may induce locally non-Euclidean regions (e.g. at Bianchi tppes VII_0).

M. Rainer

1996-02-28T23:59:59.000Z

404

Kinetic Bounding Volume Hierarchies for Collision Detection of Deformable Objects  

E-Print Network [OSTI]

We present novel algorithms for updating bounding volume hierarchies of objects undergoing arbitrary deformations. Therefore, we introduce two new data structures, the kinetic AABB tree and the kinetic BoxTree. The event-based approach of the kinetic data structures framework enables us to show that our algorithms are optimal in the number of updates. Moreover, we show a lower bound for the total number of BV updates, which is independent of the number of frames. Furthermore, we present a kinetic data structures which uses the kinetic AABB tree for collision detection and show that this structure can be easily extended for continuous collision detection of deformable objects. We performed a comparison of our kinetic approaches with the classical bottom-up update method. The results show that our algorithms perform up to ten times faster in practically relevant scenarios.

Gabriel Zachmann; Rene Weller

2006-01-01T23:59:59.000Z

405

A new approach to deformation equations of noncommutative KP hierarchies  

E-Print Network [OSTI]

Partly inspired by Sato's theory of the Kadomtsev-Petviashvili (KP) hierarchy, we start with a quite general hierarchy of linear ordinary differential equations in a space of matrices and derive from it a matrix Riccati hierarchy. The latter is then shown to exhibit an underlying 'weakly nonassociative' (WNA) algebra structure, from which we can conclude, refering to previous work, that any solution of the Riccati system also solves the potential KP hierarchy (in the corresponding matrix algebra). We then turn to the case where the components of the matrices are multiplied using a (generalized) star product. Associated with the deformation parameters, there are additional symmetries (flow equations) which enlarge the respective KP hierarchy. They have a compact formulation in terms of the WNA structure. We also present a formulation of the KP hierarchy equations themselves as deformation flow equations.

Aristophanes Dimakis; Folkert Muller-Hoissen

2007-03-21T23:59:59.000Z

406

Highly deformed high-spin band in {sup 125}I  

SciTech Connect (OSTI)

High-spin states in {sup 125}I have been investigated using the reaction {sup 82}Se({sup 48}Ca, p4n) at a beam energy of 200 MeV and {gamma}-ray coincidence events were detected using the Gammasphere spectrometer. A deformed rotational band, extending up to I{sup {pi}=}95/2{sup -}, was observed for the first time in a heavier odd-A iodine nucleus. The characteristics of the band are very similar to those of the highly deformed bands observed recently in neighboring nuclei and it is essentially identical to one of the previously known bands in {sup 126}Xe. The experimental results are compared to cranked Nilsson-Strutinsky calculations and possible configurations for the band are discussed.

Singh, Purnima; Nag, Somnath; Singh, A. K.; Ragnarsson, I.; Huebel, H.; Al-Khatib, A.; Bringel, P.; Engelhardt, C.; Neusser-Neffgen, A.; Hagemann, G. B.; Hansen, C. R.; Herskind, B.; Sletten, G.; Bracco, A.; Benzoni, G.; Camera, F.; Fallon, P.; Clark, R. M.; Carpenter, M. P.; Janssens, R. V. F. [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur, IN-721302 (India); Department of Mathematical Physics, Lund Institute of Technology, Box 118, S-221 Lund (Sweden); Helmholtz-Institut fuer Strahlen- und Kernphysik, Universitaet Bonn, Nussallee 14-16, D-53115 Bonn (Germany); Niels Bohr Institute, Blegdamsvej 17, DK-2100 Copenhagen O (Denmark); Dipartimento di Fisica, Universita di Milano and INFN, Sezione di Milano, I-20133 Milano (Italy); Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Department of Physics, University of Massachusetts Lowell, Lowell, Massachusetts 01854 (United States); Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2011-08-15T23:59:59.000Z

407

DR. BRIDGET R. SMITH-KONTER Department of Geological Sciences, University of Texas at El Paso  

E-Print Network [OSTI]

DR. BRIDGET R. SMITH-KONTER Department of Geological Sciences, University of Texas at El Paso 500 W tidally-driven failure dynamics and crustal deformation mechanisms of fractures on satellites of the outer Development and application of tidally-driven 3-D viscoelastic stress accumulation model for icy fractures

Smith-Konter, Bridget

408

DR. BRIDGET R. SMITH-KONTER Department of Geological Sciences, University of Texas at El Paso  

E-Print Network [OSTI]

DR. BRIDGET R. SMITH-KONTER Department of Geological Sciences, University of Texas at El Paso 500 W deformation mechanisms of fractures on satellites of the outer Solar System Development of 3D visualization viscoelastic stress accumulation model for icy fractures on Saturn's moon Enceladus 2005-2007 Postdoctoral

Smith-Konter, Bridget

409

Deformation of shale: mechanical properties and indicators of mechanisms  

E-Print Network [OSTI]

Basins, shales of Devonian age are commonly considered reservoir rocks I' or natural gas [Woodward, 1958; Lockett, 1968; Long, 1979; Gonzales and Johnson, 1985], Economic gas production from the Devonian shales of these basins is associated...] and slates [Donath, 1961], may be expected to be weak. Finally, Microstructural studies of deformed shales have been restricted by optical resolution, and the role of crystal plasticity in clays may have been overlooked. Results for the brittle and semi...

Ibanez, William Dayan

1993-01-01T23:59:59.000Z

410

Whittaker vector of deformed Virasoro algebra and Macdonald symmetric functions  

E-Print Network [OSTI]

We give a proof of Awata and Yamada's conjecture for the explicit formula of Whittaker vector of the deformed Virasoro algebra realized in the Fock space. The formula is expressed as a summation over Macdonald symmetric functions with factored coefficients. In the proof we fully use currents appearing in the Fock representation of Ding-Iohara-Miki quantum algebra. We also mention an interpretation of Whittaker vector in terms of the geometry of the Hilbert schemes of points on the affine plane.

Shintarou Yanagida

2014-02-12T23:59:59.000Z

411

Survey of odd-odd deformed nuclear spectroscopy  

SciTech Connect (OSTI)

In this paper, we survey the current experimental data that support assignment of rotational bands in odd-odd deformed nuclear in the rare earth and actinide regions. We present the results of a new study of {sup 170}Mt nuclear structure. In a comparing experimental and calculated Gallagher-Moszkowski matrix elements for rare earth-region nuclei, we have developed a new approach to the systematics of these matrix elements.

Hoff, R.W.

1993-09-14T23:59:59.000Z

412

Method for making biaxially textured articles by plastic deformation  

DOE Patents [OSTI]

A method of preparing a biaxially textured article comprises the steps of providing a metal preform, coating or laminating the preform with a metal layer, deforming the layer to a sufficient degree, and rapidly recrystallizing the layer to produce a biaxial texture. A superconducting epitaxial layer may then be deposited on the biaxial texture. In some embodiments the article further comprises buffer layers, electromagnetic devices or electro-optical devices.

Goyal, Amit (Knoxville, TN)

2002-01-01T23:59:59.000Z

413

Deformation analysis of local ply curvature in laminated composites  

E-Print Network [OSTI]

composite laminates with local ply curvatures in the main load- carrying layers, Strains in corrugated layers, In-Phase layers, and Out-of-Phase layers are predicted for various geometries and material configurations by assuming matrix layers as elastic.... 2 Copper Matrix Metal Composite Fig. 3 Wavy Layers 12 Fig. 4 Moment Equilibrium in a Corrugated Beam without Matrix Material 18 Fig. 5 Deformation of the Matrix Naterial Due to Stretching of the Initial Curvature of the Main Load...

Lee, Jong-Won

1987-01-01T23:59:59.000Z

414

2008 Rock Deformation GRC - Conference August 3-8, 2008  

SciTech Connect (OSTI)

The GRC on Rock Deformation highlights the latest research in brittle and ductile rock mechanics from experimental, field and theoretical perspectives. The conference promotes a multi-disciplinary forum for assessing our understanding of rock strength and related physical properties in the Earth. The theme for the 2008 conference is 'Real-time Rheology'. Using ever-improving geophysical techniques, our ability to constrain the rheological behavior during earthquakes and post-seismic creep has improved significantly. Such data are used to investigate the frictional behavior of faults, processes responsible for strain localization, the viscosity of the lower crust, and viscous coupling between the crust and mantle. Seismological data also provide information on the rheology of the lower crust and mantle through analysis of seismic attenuation and anisotropy. Geologists are improving our understanding of rheology by combining novel analyses of microstructures in naturally deformed rocks with petrologic data. This conference will bring together experts and students in these research areas with experimentalists and theoreticians studying the same processes. We will discuss and assess where agreement exists on rheological constraints derived at different length/time scales using different techniques - and where new insight is required. To encompass the elements of these topics, speakers and discussion leaders with backgrounds in geodesy, experimental rock deformation, structural geology, earthquake seismology, geodynamics, glaciology, materials science, and mineral physics will be invited to the conference. Thematic sessions will be organized on the dynamics of earthquake rupture, the rheology of the lower crust and coupling with the upper mantle, the measurement and interpretation of seismic attenuation and anisotropy, the dynamics of ice sheets and the coupling of reactive porous flow and brittle deformation for understanding geothermal and chemical properties of the shallow crust that are important for developing ideas in CO2 sequestration, geothermal and petrochemical research and the mechanics of shallow faults.

James G. Hirth

2009-09-21T23:59:59.000Z

415

SU(3) symmetry in the triaxially deformed harmonic oscillator  

SciTech Connect (OSTI)

An anisotropic harmonic oscillator Hamiltonian can be brought into invariant form under SU(3) transformations by applying nonlinear transformations to the oscillator bosons. The classification of the single-particle levels based on this covering group predicts magic numbers for the triaxial oscillator. It is shown that when the deformation |{delta}| is not too large, the physical operators are approximated by the group operators. Estimation is carried out for the alignment of orbital angular momentum in a triaxial field.

Sugawara-Tanabe, Kazuko [Otsuma Women's University, Tama, Tokyo 206-8540 (Japan); Tanabe, Kosai [Department of Physics, Saitama University, Sakura-Ku, Saitama 338-8570 (Japan); Theoretical Nuclear Physics Laboratory, RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan); Arima, Akito [Science Museum, Japan Science Foundation, Tokyo 102-0091 (Japan); Gruber, Bruno [College of Science, Southern Illinois University, Carbondale, Illinois 62901 (United States)

2009-10-15T23:59:59.000Z

416

Halos in a deformed relativistic Hartree-Bogoliubov theory in continuum  

SciTech Connect (OSTI)

In this contribution we present some recent results about neutron halos in deformed nuclei. A deformed relativistic Hartree-Bogoliubov theory in continuumhas been developed and the halo phenomenon in deformed weakly bound nuclei is investigated. These weakly bound quantum systems present interesting examples for the study of the interdependence between the deformation of the core and the particles in the halo. Magnesium and neon isotopes are studied and detailed results are presented for the deformed neutron-rich and weakly bound nuclei {sup 42}Mg. The core of this nucleus is prolate, but the halo has a slightly oblate shape. This indicates a decoupling of the halo orbitals from the deformation of the core. The generic conditions for the existence of halos in deformed nuclei and for the occurrence of this decoupling effect are discussed.

Li Lulu; Meng Jie; Ring, P.; Zhao Enguang; Zhou Shangui [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China) and Department of Physics, University of Stellenbosch, Stellenbosch (South Africa); Physikdepartment, Technische Universitaet Muenchen, 85748 Garching (Germany) and State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190 (China) and Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000 (China)

2012-10-20T23:59:59.000Z

417

Modeling Micro-Damage Healing Mechanism at Micro-Scale  

E-Print Network [OSTI]

), the corresponding results of stress and displacement fields in elastic media are converted into viscoelastic media. Since asphalt has time-dependent material properties, the viscoelastic result is more accurate than the elastic. It is shown that an increase...

Arastoo, Mahsa

2013-08-06T23:59:59.000Z

418

Modeling  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

an implementation of a single-fluid inter- face model in the ALE-AMR code to simulate surface tension effects. The model does not require explicit information on the physical...

419

Master Thesis Phase-field Modeling of  

E-Print Network [OSTI]

Department of Ferrous Technology (Computational Metallurgy) Graduate Institute of Ferrous Technology Pohang of Ferrous Technology (Computational Metallurgy) Graduate Institute of Ferrous Technology Pohang University-field Modeling of Crystal Growth during Deformation Department of Ferrous Technology (Computational Metallurgy

Cambridge, University of

420

Characterization Of High-Stroke High-Aspect Ratio Micro Electro Mechanical Systems Deformable Mirrors For Adaptive Optics  

E-Print Network [OSTI]

Journal of Microelectromechanical Systems 8, 497– 8)High-aspect ratio microelectromechanical systems deformable

Bouchti, Mohamed Amine

2013-01-01T23:59:59.000Z

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421

Modeling the mechanical response of PBX 9501  

SciTech Connect (OSTI)

An engineering overview of the mechanical response of Plastic-Bonded eXplosives (PBXs), specifically PBX 9501, will be provided with emphasis on observed mechanisms associated with different types of mechanical testing. Mechanical tests in the form of uniaxial tension, compression, cyclic loading, creep (compression and tension), and Hopkinson bar show strain rate and temperature dependence. A range of mechanical behavior is observed which includes small strain recoverable response in the form of viscoelasticity; change in stiffness and softening beyond peak strength due to damage in the form microcracks, debonding, void formation and the growth of existing voids; inelastic response in the form of irrecoverable strain as shown in cyclic tests, and viscoelastic creep combined with plastic response as demonstrated in creep and recovery tests. The main focus of this paper is to elucidate the challenges and issues involved in modeling the mechanical behavior of PBXs for simulating thermo-mechanical responses in engineering components. Examples of validation of a constitutive material model based on a few of the observed mechanisms will be demonstrated against three point bending, split Hopkinson pressure bar and Brazilian disk geometry.

Ragaswamy, Partha [Los Alamos National Laboratory; Lewis, Matthew W [Los Alamos National Laboratory; Liu, Cheng [Los Alamos National Laboratory; Thompson, Darla G [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

422

High Shear Deformation to Produce High Strength and Energy Absorption in Mg Alloys  

SciTech Connect (OSTI)

Magnesium alloys have the potential to reduce the mass of transportation systems however to fully realize the benefits it must be usable in more applications including those that require higher strength and ductility. It has been known that fine grain size in Mg alloys leads to high strength and ductility. However, the challenge is how to achieve this optimal microstructure in a cost effective way. This work has shown that by using optimized high shear deformation and second phase particles of Mg2Si and MgxZnZry the energy absorption of the extrusions can exceed that of AA6061. The extrusion process under development described in this presentation appears to be scalable and cost effective. In addition to process development a novel modeling approach to understand the roles of strain and state-of-strain on particle fracture and grain size control has been developed

Joshi, Vineet V.; Jana, Saumyadeep; Li, Dongsheng; Garmestani, Hamid; Nyberg, Eric A.; Lavender, Curt A.

2014-02-01T23:59:59.000Z

423

Deformation and the Nuclear Matrix Elements of the Neutrinoless Double Beta Decay  

E-Print Network [OSTI]

In this talk I will review the "state of the art" of the calculations of the nuclear matrix elements (NME) of the neutrinoless double beta decays for the nuclei 48Ca, 76Ge, 82Se, 124Sn, 128Te, 130Te and 136Xe in the framework of the Interacting Shell Model (ISM), and compare them with the NME's obtained using the Quasi-particle RPA approach (QRPA). I will also discuss the effect of the competition between the pairing and quadrupole correlations in the value of these NME's. In particular I will show that, as the difference in deformation between parent and grand daughter grows, the NME's of both the neutrinoless and the two neutrino modes decrease rapidly.

J. Menendez; A. Poves; E. Caurier; F. Nowacki

2008-09-12T23:59:59.000Z

424

Adhesive joint and composites modeling in SIERRA.  

SciTech Connect (OSTI)

Polymers and fiber-reinforced polymer matrix composites play an important role in many Defense Program applications. Recently an advanced nonlinear viscoelastic model for polymers has been developed and incorporated into ADAGIO, Sandia's SIERRA-based quasi-static analysis code. Standard linear elastic shell and continuum models for fiber-reinforced polymer-matrix composites have also been added to ADAGIO. This report details the use of these models for advanced adhesive joint and composites simulations carried out as part of an Advanced Simulation and Computing Advanced Deployment (ASC AD) project. More specifically, the thermo-mechanical response of an adhesive joint when loaded during repeated thermal cycling is simulated, the response of some composite rings under internal pressurization is calculated, and the performance of a composite container subjected to internal pressurization, thermal loading, and distributed mechanical loading is determined. Finally, general comparisons between the continuum and shell element approaches for modeling composites using ADAGIO are given.

Ohashi, Yuki; Brown, Arthur A.; Hammerand, Daniel Carl; Adolf, Douglas Brian; Chambers, Robert S.; Foulk, James W., III (.,; )

2005-11-01T23:59:59.000Z

425

An elastic, plastic, viscous model for slow shear of a liquid foam  

E-Print Network [OSTI]

We suggest a scalar model for deformation and flow of an amorphous material such as a foam or an emulsion. To describe elastic, plastic and viscous behaviours, we use three scalar variables: elastic deformation, plastic deformation rate and total deformation rate; and three material specific parameters: shear modulus, yield deformation and viscosity. We obtain equations valid for different types of deformations and flows slower than the relaxation rate towards mechanical equilibrium. In particular, they are valid both in transient or steady flow regimes, even at large elastic deformation. We discuss why viscosity can be relevant even in this slow shear (often called "quasi-static") limit. Predictions of the storage and loss moduli agree with the experimental literature, and explain with simple arguments the non-linear large amplitude trends.

Philippe Marmottant; François Graner

2007-07-06T23:59:59.000Z

426

Finite Deformation of Materials with an Ensemble of Defects  

SciTech Connect (OSTI)

The theory of large deformations developed here is closely related to continuum mechanics but it differs in several major respects, especially in considering the deformation associated with various types of physical behavior, making it possible to synthesize a general approach to formulating constitutive laws. One goal is to derive general concepts of strain, strain rate, stress, and stress rate that are somewhat more physics-based than in most standard works on continuum mechanics, and to demonstrate some new relations between these quantities. With these concepts it is possible to develop a generalized principle of superposition of strain rates (GSSR) that accounts for damage as well as plastic flow. The traditional superposition of strain rates allows for addition of elastic and plastic strain rates and is commonly thought to be valid only for small strains. The GSSR allows us to compute deformations involving plastic flow and, in addition, brittle failure, fragmentation, high-pressure effects and other types of behavior as necessary, and the theory is valid for arbitrarily large deformations. In fact, GSSR is derived from more basic ideas and has broader application than the standard superposition of strain rates. The physical basis for calculations of complex material response is developed in a separate report. The implementation into the SCRAM computer program is documented separately. The polar decomposition theorem is taken as a starting point for the theory of large deformation, an approach somewhat different from that usually taken in continuum mechanics. Two sets of orthogonal axes are distinguished, space axes that are fixed in ambient space, and polar axes that are related to material deformation. This clarifies several concepts; for example, it is shown that the Signorini and Green-St. Venant strains are actually measures of the same physical entity, one in space axes and the other in polar axes. It follows that they are not competing measures, as is often implied in traditional continuum mechanics. It also follows that Piola stress is a measure in polar axes, while Cauchy stress is a measure in space axes. Another consequence of polar decomposition is a proof that vorticity is not a measure of the rate of material rotation (as is often stated in the hydrodynamics literature) but that they are related. This allows us to develop an exact approach to computing rates of tensor quantities, called polar rates, that account for material rotation in an exact way. This leads to a simple relation between Signorini strain rate and stretching (the symmetric part of the velocity gradient). It also follows that the polar stress rate is the appropriate measure for the rate of change of Cauchy stress, and that the more traditional stress rate of Zaremba, Jaumann, and Noll is only an approximation, valid at small strains. Examples are described for materials undergoing simple shear, vortex motion, and torsion.

J.K. Dienes

2003-01-01T23:59:59.000Z

427

Deformation and fracture characteristics of spent Zircaloy fuel cladding  

SciTech Connect (OSTI)

For a better understanding of Zircaloy fuel-rod failure by the pellet-cladding interaction (PCI) phenomenon, a mechanistic study of deformation and fracture behavior of spent power reactor fuel cladding under simulated PCI conditions was conducted. Zircaloy-2 cladding specimens, obtained from fuel assemblies of operating power reactors, were deformed to fracture at 325/sup 0/C by internal gas pressurization in the absence of fission product simulants. Fracture characteristics and microstructures were examined via SEM, TEM, and HVEM. Numerous dislocation tangles and cell structures, observed in TEM specimens of cladding tubes that failed in a ductile manner, were consistent with SEM observations of a limited number of dimples characteristic of microvoid coalescence. A number of brittle-type failures were produced without the influence of fission product simulants. The brittle cracks occurred near the areas compressed by the Swagelok fittings of the internally pressurized tube and propagated from the outer to the inner surface. Since the outer surface was isolated and maintained under a flowing stream of pure helium, it is unlikely that the brittle-type failure was influenced by any fission product traces. SEM fractography of the brittle-type failure revealed a large area of transgranular pseudocleavage with limited areas of ductile fluting, which were similar in appearance to the surfaces produced by in-reactor PCI-type failures. A TEM evaluation of the cladding in the vicinity of the through-wall crack revealed numerous locations that contained an extensive amount of second-phase precipitate (Zr/sub 3/O). We believe that the brittle-type failures of the irradiated spent fuel cladding in the stress rupture experiments are associated with segregation of oxygen, which leads to the formation of the order structure, an immobilization of dislocations, and minimal plastic deformation in the material.

Chung, H.M.; Yaggee, F.L.

1982-09-01T23:59:59.000Z

428

Strict deformation quantization for a particle in a magnetic field  

SciTech Connect (OSTI)

Recently, we introduced a mathematical framework for the quantization of a particle in a variable magnetic field. It consists in a modified form of the Weyl pseudodifferential calculus and a C*-algebraic setting, these two points of view being isomorphic in a suitable sense. In the present paper we leave Planck's constant vary, showing that one gets a strict deformation quantization in the sense of Rieffel. In the limit ({Dirac_h}/2{pi}){yields}0 one recovers a Poisson algebra induced by a symplectic form defined in terms of the magnetic field.

Mantoiu, Marius; Purice, Radu [Institute of Mathematics ''Simion Stoilow'' of the Romanian Academy, P.O. Box 1-764, Bucarest, RO-014700 (Romania)

2005-05-01T23:59:59.000Z

429

The nature of quasistatic deformation in granular materials  

E-Print Network [OSTI]

Strain in granular materials in quasistatic conditions under varying stress originate in (I) contact deformation and (II) rearrangements of the contact network. Depending on sample history and applied load, either mechanism might dominate. One may thus define rheological regimes I and II accordingly. Their properties are presented and illustrated here with discrete numerical simulation results on sphere packings. Understanding the microscopic physical origin of strain enables one to clarify such issues as the existence of macroscopic elasticity, the approach to stress-strain relations in the large system limit and the sensitivity to noise.

Jean-Noël Roux

2009-01-15T23:59:59.000Z

430

Deformed one-quasiparticle states in covariant density functional theory  

E-Print Network [OSTI]

Systematic investigation of the accuracy of the description of the energies of deformed one-quasiparticle states has been performed in covariant density functional theory in actinide and rare-earth mass regions. The sources of the discrepancies between theory and experiment are analyzed. Although some improvements in the description of ground state configurations and one-quasiparticle spectra can be achieved by better parametrization of the relativistic mean field Lagrangian, the analysis suggests that spectroscopic quality of their description can be achieved only in theoretical framework which takes into account particle-vibration coupling.

A. V. Afanasjev; S. Shawaqfeh

2012-05-10T23:59:59.000Z

431

Giant Monopole Resonance in Transitional and Deformed-Nuclei  

E-Print Network [OSTI]

=129 MeV on ' ' Sm and ' ' ' Nd to investigate the giant monopole resonance in transitional and deformed nuclei. The experimental data reveal a mixing of I.=0 and I.=2 modes in '" Sm resulting in almost identi- cal angular distributions for the two... components of the giant resonance peaks in the angular range 2'?6. A "splitting" of the giant monopole resonance is observed in ' Nd; the extent of this split- ting is sma11er than that reported for ' "Sm. Comparison is made with the predictions of various...

Garg, U.; Bogucki, P.; Bronson, J. D.; Lui, YW; Youngblood, David H.

1984-01-01T23:59:59.000Z

432

Mineral Deformation at Earth's Core-Mantle Boundary  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment SurfacesResource Program PreliminaryA3,0 Alabama - Natural GasMineral Deformation at

433

Mineral Deformation at Earth's Core-Mantle Boundary  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment SurfacesResource Program PreliminaryA3,0 Alabama - Natural GasMineral Deformation

434

A magnetic liquid deformable mirror for high stroke and low order axially symmetrical aberrations  

E-Print Network [OSTI]

We present a new class of magnetically shaped deformable liquid mirrors made of a magnetic liquid (ferrofluid). Deformable liquid mirrors offer advantages with respect to deformable solid mirrors: large deformations, low costs and the possibility of very large mirrors with added aberration control. They have some disadvantages (e.g. slower response time). We made and tested a deformable mirror, producing axially symmetrical wavefront aberrations by applying electric currents to 5 concentric coils made of copper wire wound on aluminum cylinders. Each of these coils generates a magnetic field which combines to deform the surface of a ferrofluid to the desired shape. We have carried out laboratory tests on a 5 cm diameter prototype mirror and demonstrated defocus as well as Seidel and Zernike spherical aberrations having amplitudes up to 20 microns, which was the limiting measurable amplitude of our equipment

Brousseau, D; Parent, J; Ruel, H J; Borra, Ermanno F.; Brousseau, Denis; Parent, Jocelyn; Ruel, Hubert-Jean

2006-01-01T23:59:59.000Z

435

A magnetic liquid deformable mirror for high stroke and low order axially symmetrical aberrations  

E-Print Network [OSTI]

We present a new class of magnetically shaped deformable liquid mirrors made of a magnetic liquid (ferrofluid). Deformable liquid mirrors offer advantages with respect to deformable solid mirrors: large deformations, low costs and the possibility of very large mirrors with added aberration control. They have some disadvantages (e.g. slower response time). We made and tested a deformable mirror, producing axially symmetrical wavefront aberrations by applying electric currents to 5 concentric coils made of copper wire wound on aluminum cylinders. Each of these coils generates a magnetic field which combines to deform the surface of a ferrofluid to the desired shape. We have carried out laboratory tests on a 5 cm diameter prototype mirror and demonstrated defocus as well as Seidel and Zernike spherical aberrations having amplitudes up to 20 microns, which was the limiting measurable amplitude of our equipment

Denis Brousseau; Ermanno F. Borra; Hubert-Jean Ruel; Jocelyn Parent

2006-11-15T23:59:59.000Z

436

The $?$-deformed Segal-Bargmann transform is a Hall type transform  

E-Print Network [OSTI]

We present an explanation of how the $\\mu$-deformed Segal-Bargmann spaces, that are studied in various articles of the author in collaboration with Angulo, Echevarria and Pita, can be viewed as deserving their name, that is, how they should be considered as a part of Segal-Bargmann analysis. This explanation relates the $\\mu$-deformed Segal-Bargmann transforms to the generalized Segal-Bargmann transforms introduced by B. Hall using heat kernel analysis. All the versions of the $\\mu$-deformed Segal-Bargmann transform can be understood as Hall type transforms. In particular, we define a $\\mu$-deformation of Hall's "Version C" generalized Segal-Bargmann transform which is then shown to be a $\\mu$-deformed convolution with a $\\mu$-deformed heat kernel followed by analytic continuation. Our results are generalizations and analogues of the results of Hall.

Stephen Bruce Sontz

2009-07-13T23:59:59.000Z

437

THEORETICAL INVESTIGATION OF MICROSTRUCTURE EVOLUTION AND DEFORMATION OF ZIRCONIUM UNDER CASCADE DAMAGE CONDITIONS  

SciTech Connect (OSTI)

This work is based on our reaction-diffusion model of radiation growth of Zr-based materials proposed recently in [1]. In [1], the equations for the strain rates in unloaded pure crystal under cascade damage conditions of, e.g., neutron or heavy-ion irradiation were derived as functions of dislocation densities, which include contributions from dislocation loops, and spatial distribution of their Burgers vectors. The model takes into account the intra-cascade clustering of self-interstitial atoms and their one-dimensional diffusion; explains the growth stages, including the break-away growth of pre-annealed samples; and accounts for some striking observations, such as of negative strain in prismatic direction, and co-existence of vacancy- and interstitial-type prismatic loops. In this report, the change of dislocation densities due to accumulation of sessile dislocation loops is taken into account explicitly to investigate the dose dependence of radiation growth. The dose dependence of climb rates of dislocations is calculated, which is important for the climb-induced glide model of radiation creep. The results of fitting the model to available experimental data and some numerical calculations of the strain behavior of Zr for different initial dislocation structures are presented and discussed. The computer code RIMD-ZR.V1 (Radiation Induced Microstructure and Deformation of Zr) developed is described and attached to this report.

Barashev, Alexander V [ORNL; Golubov, Stanislav I [ORNL; Stoller, Roger E [ORNL

2012-06-01T23:59:59.000Z

438

Determination of the critical degree of deformation of zirconium and Zr-1% Nb alloy  

SciTech Connect (OSTI)

The critical degree of deformation of zirconium-1% niobium alloy and of pure zirconium melted and worked under the same conditions in an inert atmosphere was determined. Commercial iodide zirconium was used as the charge and the niobium content in the N-1 alloy was 0.98% wt. The critical degree of deformation was determined by compulsory averaging of the deformation intervals. To increase the accuracy of the experiments the use of recrystallized material was recommended.

Chirkin, A.V.; Shibani, I.

1988-03-01T23:59:59.000Z

439

Morphology, deformation, and defect structures of TiCr{sub 2} in Ti-Cr alloys  

SciTech Connect (OSTI)

The morphologies and defect structures of TiCr{sub 2} in several Ti-Cr alloys have been examined by optical metallography, x-ray diffraction, and transmission electron microscopy (TEM), in order to explore the room-temperature deformability of the Laves phase TiCr{sub 2}. The morphology of the Laves phase was found to be dependent upon alloy composition and annealing temperature. Samples deformed by compression have also been studied using TEM. Comparisons of microstructures before and after deformation suggest an increase in twin, stacking fault, and dislocation density within the Laves phase, indicating some but not extensive room-temperature deformability.

Chen, K.C.; Allen, S.M.; Livingston, J.D.

1992-12-31T23:59:59.000Z

440

PHYSICAL NATURE OF SHEAR BANDS FORMATION AND CONSTITUTIVE MODELLING FOR PLASTIC INSTABILITY  

E-Print Network [OSTI]

697 PHYSICAL NATURE OF SHEAR BANDS FORMATION AND CONSTITUTIVE MODELLING FOR PLASTIC INSTABILITYtokrzyska 21,00-049 Warsaw,Poland Revue Phys. Appl. 23 (1988) 697 AVRIL 1988, Studies of plastic deformation dependent hardening property can be pivotal in the modelling for plastic deform- ation instability

Paris-Sud XI, Université de

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Postirradiation deformation of ferritic Fe-Cr binary alloys  

SciTech Connect (OSTI)

Six binary Fe-Cr alloys ranging from 3 to 18% chromium were irradiated in the form of miniature tensile specimens in the Fast Flux Test Facility and tested at room temperature. The irradiation conditions produced 7 to 30 dpa at 365 to 574{degrees}C. The major purpose of the experiment was to compare the behavior of these simple alloys with that of more complex commercial alloys, The tensile data obtained on these specimens at room temperature are discussed with appropriate fractographic and microstructural support. Previous studies on similar materials had revealed the presence of a feature typically exhibited in channel fractures: elongated voids were evident in shear bands of an irradiated and deformed TEM disk of a binary Fe-6Cr alloy. An additional purpose of the experiment was therefore to provide a better understanding of the potential contribution of channel fracture to deformation in ferritic alloys. No evidence for channel fracture was found, however. 14 refs., 6 figs., 2 tabs.

Hamilton, M.L.; Gelles, D.S.

1991-06-01T23:59:59.000Z

442

Method to adjust multilayer film stress induced deformation of optics  

DOE Patents [OSTI]

A buffer-layer located between a substrate and a multilayer for counteracting stress in the multilayer. Depositing a buffer-layer having a stress of sufficient magnitude and opposite in sign reduces or cancels out deformation in the substrate due to the stress in the multilayer. By providing a buffer-layer between the substrate and the multilayer, a tunable, near-zero net stress results, and hence results in little or no deformation of the substrate, such as an optic for an extreme ultraviolet (EUV) lithography tool. Buffer-layers have been deposited, for example, between Mo/Si and Mo/Be multilayer films and their associated substrate reducing significantly the stress, wherein the magnitude of the stress is less than 100 MPa and respectively near-normal incidence (5.degree.) reflectance of over 60% is obtained at 13.4 nm and 11.4 nm. The present invention is applicable to crystalline and non-crystalline materials, and can be used at ambient temperatures.

Mirkarimi, Paul B. (Sunol, CA); Montcalm, Claude (Livermore, CA)

2000-01-01T23:59:59.000Z

443

Investigating Deformation and Failure Mechanisms in Nanoscale Multilayer Metallic Composites  

SciTech Connect (OSTI)

Over the history of materials science there are many examples of materials discoveries that have made superlative materials; the strongest, lightest, or toughest material is almost always a goal when we invent new materials. However, often these have been a result of enormous trial and error approaches. A new methodology, one in which researchers design, from the atoms up, new ultra-strong materials for use in energy applications, is taking hold within the science and engineering community. This project focused on one particular new classification of materials; nanolaminate metallic composites. These materials, where two metallic materials are intimately bonded and layered over and over to form sheets or coatings, have been shown over the past decade to reach strengths over 10 times that of their constituents. However, they are not yet widely used in part because while extremely strong (they don’t permanently bend), they are also not particularly tough (they break relatively easily when notched). Our program took a coupled approach to investigating new materials systems within the laminate field. We used computational materials science to explore ways to institute new deformation mechanisms that occurred when a tri-layer, rather than the more common bi-layer system was created. Our predictions suggested that copper-nickel or copper-niobium composites (two very common bi-layer systems) with layer thicknesses on the order of 20 nm and then layered 100’s of times, would be less tough than a copper-nickel-niobium metallic composite of similar thicknesses. In particular, a particular mode of permanent deformation, cross-slip, could be activated only in the tri-layer system; the crystal structure of the other bi-layers would prohibit this particular mode of deformation. We then experimentally validated this predication using a wide range of tools. We utilized a DOE user facility, the Center for Integrated Nanotechnology (CINT), to fabricate, for the first time, these tri-layer composites. CINT formed nanolaminate composites were tested in tension, with bulge testing, using nanoindentation, and using micro-compression testing to demonstrate that the tri-layer films were indeed tougher and hardened more during deformation (they got stronger as we deformed them) than equivalent bi-layers. The seven graduate students, 4 post-docs and research faculty, and the two faculty co-PI’s were able to create a collaborated computational prediction and experimental validation team to demonstrate the benefits of this class of materials to the community. The computational work crossed from atomistic to bulk simulations, and the experiments coupled form nm-scale to the mm scale; closely matching the simulations. The simulations provided viable mechanisms that explained the observed results, and new experimental results were used to push the boundaries of the simulation tools. Over the life of the 7 years of this program we proved that tri-layer nanolaminate metallic composite systems exceeded the mechanical performance of bi-layer systems if the right materials were chosen, and that the mechanism responsible for this was tied to the cross slip of dislocations. With 30 journal publications resulting from this work we have broadly disseminated this family of results to the scientific community.

Zbib, Hussein M [Washington State University; Bahr, David F [Purdue University

2014-10-22T23:59:59.000Z

444

Modeling  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

a single-fluid diffuse interface model in the ALE-AMR hydrodynamics code to simulate surface tension effects. We show simula- tions and compare them to other surface tension...

445

Modeling  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

sion effects. We show the result of a test case, and compare it to the result without surface tension. The model describes droplet formation nicely. Application The ARRA-funded...

446

Rheological Model for Wood  

E-Print Network [OSTI]

Wood as the most important natural and renewable building material plays an important role in the construction sector. Nevertheless, its hygroscopic character basically affects all related mechanical properties leading to degradation of material stiffness and strength over the service life. Accordingly, to attain reliable design of the timber structures, the influence of moisture evolution and the role of time- and moisture-dependent behaviors have to be taken into account. For this purpose, in the current study a 3D orthotropic elasto-plastic, visco-elastic, mechano-sorptive constitutive model for wood, with all material constants being defined as a function of moisture content, is presented. The corresponding numerical integration approach, with additive decomposition of the total strain is developed and implemented within the framework of the finite element method (FEM). Moreover to preserve a quadratic rate of asymptotic convergence the consistent tangent operator for the whole model is derived. Functionality and capability of the presented material model are evaluated by performing several numerical verification simulations of wood components under different combinations of mechanical loading and moisture variation. Additionally, the flexibility and universality of the introduced model to predict the mechanical behavior of different species are demonstrated by the analysis of a hybrid wood element. Furthermore, the proposed numerical approach is validated by comparisons of computational evaluations with experimental results.

Mohammad Masoud Hassani; Falk K. Wittel; Stefan Hering; Hans J. Herrmann

2014-10-15T23:59:59.000Z

447

Beta relaxation in the shear mechanics of equilibrium viscous liquids: Phenomenology and network modeling of the alpha-beta merging region  

E-Print Network [OSTI]

The phenomenology of the beta relaxation process in the shear-mechanical response of glass-forming liquids is summarized and compared to that of the dielectric beta process. Furthermore, we discuss how to model the observations by means of standard viscoelastic modeling elements. Necessary physical requirements to such a model are outlined, and it is argued that physically relevant models must be additive in the shear compliance of the alpha and beta parts. A model based on these considerations is proposed and fitted to data for Polyisobutylene 680.

Bo Jakobsen; Kristine Niss; Claudio Maggi; Niels Boye Olsen; Tage Christensen; Jeppe C. Dyre

2010-05-26T23:59:59.000Z

448

Modelling  

E-Print Network [OSTI]

Modeling of technical machines became a standard technique since computer became powerful enough to handle the amount of data relevant to the specific system. Simulation of an existing physical device requires the knowledge of all relevant quantities. Electric fields given by the surrounding boundary as well as magnetic fields caused by coils or permanent magnets have to be known. Internal sources for both fields are sometimes taken into account, such as space charge forces or the internal magnetic field of a moving bunch of charged particles. Used solver routines are briefly described and some bench-marking is shown to estimate necessary computing times for different problems. Different types of charged particle sources will be shown together with a suitable model to describe the physical model. Electron guns are covered as well as different ion sources (volume ion sources, laser ion sources, Penning ion sources, electron resonance ion sources, and H$^-$-sources) together with some remarks on beam transport.

Spädtke, P

2013-01-01T23:59:59.000Z

449

Thermochronometric analysis of the North Lunggar Rift: Implications for the timing of extension initiation and structural style of deformation in southern Tibet  

E-Print Network [OSTI]

Hager for use of the HeMP software. v TABLE OF CONTENTS PAGE TITLE PAGE i ABSTRACT iii ACKNOWLEDGMENTS v TABLE OF CONTENTS vi LIST OF FIGURES AND TABLES x CHAPTER 1: Introduction 14... for Himalayan-Tibetan deformation 120 FIGURE 4. End member models for the development of the North Lunggar Rift 122 x FIGURE 5. Location and age of samples analyzed from the North Lunggar Rift 124 FIGURE 6. Age-elevation relationship (AER...

Sundell, Kurt E.

2011-01-01T23:59:59.000Z

450

On the Symmetry of Energy Minimising Deformations in Nonlinear Elasticity II: Compressible Materials  

E-Print Network [OSTI]

On the Symmetry of Energy Minimising Deformations in Nonlinear Elasticity II: Compressible that has less elastic energy than the given deformation, provided that the stored-energy function, of radius R > 0, centred at the origin into another such sphere Sr = urad (SR) A that encloses the same

Sivaloganathan, J.

451

Effect of plastic deformation on the formation of acicular ferrite C.H. Lee a,1  

E-Print Network [OSTI]

Effect of plastic deformation on the formation of acicular ferrite C.H. Lee a,1 , H deformation on the transformation of austenite to acicular ferrite in a FeÁ/MnÁ/SiÁ/C alloy steel containing non-metallic inclusions was investigated. The transformation to acicular ferrite is retarded

Cambridge, University of

452

Deformation-induced inverted metamorphic eld gradients: an example from the southeastern Canadian Cordillera  

E-Print Network [OSTI]

Deformation-induced inverted metamorphic ®eld gradients: an example from the southeastern Canadian allochthon and Monashee complex, exhibits an inverted metamorphic ®eld gradient. New data presented preserving evidence of strongly diachronous deformation and an apparent inverted metamorphism. # 1999

Gibson, Dan

453

Dielectric elastomer membranes undergoing inhomogeneous deformation Tianhu He,1,2  

E-Print Network [OSTI]

online 29 October 2009 Dielectric elastomers are capable of large deformation subject to an electric voltage and are promising for use as actuators, sensors, and generators. Because of large deformation inhomogeneous, and that the membrane is susceptible to several modes of failure, including electrical breakdown

Suo, Zhigang

454

FINITE-ELEMENT FORMULATIONS FOR PROBLEMS OF LARGE ELASTIC-PLASTIC DEFORMATION  

E-Print Network [OSTI]

FINITE-ELEMENT FORMULATIONS FOR PROBLEMS OF LARGE ELASTIC-PLASTIC DEFORMATION R. M. MCM~EKING and J elastic-plastic flow.The method is based on Hill's variational principle for incremental deformations in a manner which allows any conventions finite element program, for "small strain" elastic-plastic analysis

455

Interfaces and Plastic Deformation in Materials: From Theory to Engineering (3 Credits)  

E-Print Network [OSTI]

Interfaces and Plastic Deformation in Materials: From Theory to Engineering (3 Credits) Instructor in their plastic deformation. The interface structures and defects will be described at different scales. Interfaces and high temperature plasticity 11. Triple junctions: from free to constrained interfaces 12

Chen, Zheng

456

Structural Signature of Plastic Deformation in Metallic Glasses H. L. Peng,1,2  

E-Print Network [OSTI]

Structural Signature of Plastic Deformation in Metallic Glasses H. L. Peng,1,2 M. Z. Li,2,* and W the degree of local fivefold symmetry (LFFS) as the structural indicator to predict plastic deformation of local structures and find that the plastic events prefer to be initiated in regions with a lower degree

Wang, Wei Hua

457

Parametric dislocation dynamics: A thermodynamics-based approach to investigations of mesoscopic plastic deformation  

E-Print Network [OSTI]

plastic deformation N. M. Ghoniem, S.-H. Tong, and L. Z. Sun Mechanical and Aerospace Engineering 3D interacting dislocation loops. The approach is appropriate for investigations of plastic defor formation of dislocation junctions. I. INTRODUCTION A fundamental description of plastic deformation is now

Ghoniem, Nasr M.

458

Friction, Adhesion, and Deformation: Dynamic Measurements with the Atomic Force Phil Attard  

E-Print Network [OSTI]

Friction, Adhesion, and Deformation: Dynamic Measurements with the Atomic Force Microscope Phil. Adhesion Sci. Technol. 16, 753­791 (2002).) Running title: Friction, Adhesion, and Deformation Abstract for the friction force microscope, quantitative measurements of friction and the ef- fect of adhesion, measurement

Attard, Phil

459

Correlation of microseismic and chemical properties of brittle deformation in Locharbriggs sandstone  

E-Print Network [OSTI]

: stress corrosion, acoustic emission, silica dissolution, subcritical crack growth, deformation rate), 2268, doi:10.1029/2002JB002277, 2003. 1. Introduction [2] Water is ubiquitous in the Earth's crust of water influences the brittle deformation properties of rocks in two ways. The poroe- lastic effect

460

Three-dimensional deformation caused by the Bam, Iran, earthquake and the  

E-Print Network [OSTI]

Three-dimensional deformation caused by the Bam, Iran, earthquake and the origin of shallow slip on seismogenic faults. We derive the full vector displacement field due to the Bam, Iran, earthquake of moment on deformation associated with the Mw ¼ 6.5 Bam earthquake in Iran determined using the SAR data from the ERS

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Postirradiation deformation behavior in ferritic Fe-Cr alloys  

SciTech Connect (OSTI)

It has been demonstrated that fast neutron irradiation produces significant hardening in simple Fe(3-18)Cr binary alloys irradiated to about 35 dpa in the temperature range 365 to 420{degrees}C, whereas irradiation at 574{degrees}C produces hardening only for 15% or more chromium. The irradiation-induced changes in tensile properties are discussed in terms of changes in the power law work hardening exponent. The work hardening exponent of the lower chromium alloys decreased significantly after low temperature irradiation ({le}420{degrees}C) but increased after irradiation at 574{degrees}C. The higher chromium alloys failed either in cleavage or in a mixed ductile/brittle fashion. Deformation microstructures are presented to support the tensile behavior.

Hamilton, M.L.; Gelles, D.S. [Pacific Northwest Lab., Richland, VA (United States); Gardner, P.L. [Univ. of Missouri, Rolla (United States)

1992-12-31T23:59:59.000Z

462

Postirradiation deformation behavior in ferritic Fe-Cr alloys  

SciTech Connect (OSTI)

It has been demonstrated that fast-neutron irradiation produces significant hardening in simple Fe-(3-18)Cr binary alloys irradiated to about 35 dpa in the temperature range 365 to 420{degrees}C, whereas irradiation at 574{degrees}C produces hardening only for 15% or more chromium. The irradiation-induced changes in tensile properties are discussed in terms of changes in the power law work-hardening exponent. The work-hardening exponent of the lower chromium alloys decreased significantly after low-temperature irradiation ({le} 420{degrees}C) but increased after irradiation at 574{degrees}C. The higher chromium alloys failed either in cleavage or in a mixed ductile/brittle fashion. Deformation microstructures are presented to support the tensile behavior.

Hamilton, M.L.; Gelles, D.S. [Pacific Northwest Lab., Richland, WA (United States); Gardner, P.L. [Missouri Univ., Rolla, MO (United States)

1992-06-01T23:59:59.000Z

463

Postirradiation deformation behavior in ferritic Fe-Cr alloys  

SciTech Connect (OSTI)

It has been demonstrated that fast-neutron irradiation produces significant hardening in simple Fe-(3-18)Cr binary alloys irradiated to about 35 dpa in the temperature range 365 to 420[degrees]C, whereas irradiation at 574[degrees]C produces hardening only for 15% or more chromium. The irradiation-induced changes in tensile properties are discussed in terms of changes in the power law work-hardening exponent. The work-hardening exponent of the lower chromium alloys decreased significantly after low-temperature irradiation ([le] 420[degrees]C) but increased after irradiation at 574[degrees]C. The higher chromium alloys failed either in cleavage or in a mixed ductile/brittle fashion. Deformation microstructures are presented to support the tensile behavior.

Hamilton, M.L.; Gelles, D.S. (Pacific Northwest Lab., Richland, WA (United States)); Gardner, P.L. (Missouri Univ., Rolla, MO (United States))

1992-06-01T23:59:59.000Z

464

Tunneling from super- to normal-deformed minima in nuclei.  

SciTech Connect (OSTI)

An excited minimum, or false vacuum, gives rise to a highly elongated superdeformed (SD) nucleus. A brief review of superdeformation is given, with emphasis on the tunneling from the false to the true vacuum, which occurs in the feeding and decay of SD bands. During the feeding process the tunneling is between hot states, while in the decay it is from a cold to a hot state. The {gamma} spectra connecting SD and normal-deformed (ND) states provide information on several physics issues: the decay mechanism; the spin/parity quantum numbers, energies and microscopic structures of SD bands; the origin of identical SD bands; the quenching of pairing with excitation energy; and the chaoticity of excited ND states at 2.5-5 MeV. Other examples of tunneling in nuclei, which are briefly described, include the possible role of tunneling in {Delta}I = 4 bifurcation in SD bands, sub-barrier fusion and proton emitters.

Khoo, T. L.

1998-01-08T23:59:59.000Z

465

Deformation Quantization: From Quantum Mechanics to Quantum Field Theory  

E-Print Network [OSTI]

The aim of this paper is to give a basic overview of Deformation Quantization (DQ) to physicists. A summary is given here of some of the key developments over the past thirty years in the context of physics, from quantum mechanics to quantum field theory. Also, we discuss some of the conceptual advantages of DQ and how DQ may be related to algebraic quantum field theory. Additionally, our previous results are summarized which includes the construction of the Fedosov star-product on dS/AdS. One of the goals of these results was to verify that DQ gave the same results as previous analyses of these spaces. Another was to verify that the formal series used in the conventional treatment converged by obtaining exact and nonperturbative results for these spaces.

P. Tillman

2006-10-31T23:59:59.000Z

466

Deformation Quantization, Quantization, and the Klein-Gordon Equation  

E-Print Network [OSTI]

The aim of this proceeding is to give a basic introduction to Deformation Quantization (DQ) to physicists. We compare DQ to canonical quantization and path integral methods. It is described how certain issues such as the roles of associativity, covariance, dynamics, and operator orderings are understood in the context of DQ. Convergence issues in DQ are mentioned. Additionally, we formulate the Klein-Gordon (KG) equation in DQ. Original results are discussed which include the exact construction of the Fedosov star-product on the dS and AdS space-times. Also, the KG equation is written down for these space-times. This is a proceedings to the Second International Conference on Quantum Theories and Renormalization Group in Gravity and Cosmology.

P. Tillman

2007-02-28T23:59:59.000Z

467

Onset of deformation at $N = 112$ in Bi nuclei  

E-Print Network [OSTI]

The high spin states in $^{195}$Bi has been studied by $\\gamma$-ray spectroscopic method using the $^{181}$Ta($^{20}$Ne, 6n) fusion evaporation reaction at 130 MeV. The $\\gamma\\gamma$ coincidence data were taken using an array of 8 clover HPGe detectors. The spin and parity assignments of the excited states have been made from the measured directional correlation from oriented states (DCO) ratios and integrated polarization asymmetry (IPDCO) ratios. The results show, for the first time, the evidence of a rotational like band based on a 13/2$^+$ band head in this nucleus, indicating the onset of deformation at neutron number $N = 112$ for the Bismuth isotopes. The results obtained were found to be consistent with the prediction of the total Routhian surface calculations using Woods Saxon potential. The same calculations also predict a change in shape from oblate to triaxial in $^{195}$Bi at high rotational frequency.

H. Pai; G. Mukherjee; R. Raut; S. K. Basu; A. Goswami; S. Chanda; T. Bhattacharjee; S. Bhattacharyya; C. Bhattacharya; S. Bhattacharya; S. R. Banerjee; S. Kundu; K. Banerjee; A. Dey; T. K. Rana; J. K. Meena; D. Gupta; S. Mukhopadhyay; Srijit Bhattacharya; Sudeb Bhattacharya; S. Ganguly; R. Kshetri; M. K. Pradhan

2012-04-19T23:59:59.000Z

468

Noise-assisted Thouless pump in elastically deformable molecular junctions  

E-Print Network [OSTI]

We study a Thouless pump realized with an elastically \\textit{deformable quantum dot} whose center of mass follows a non-linear stochastic dynamics. The interplay of noise, non-linear effects, dissipation and interaction with an external time-dependent driving on the pumped charge is fully analyzed. The results show that the quantum pumping mechanism not only is not destroyed by the force fluctuations, but it becomes stronger when the forcing signal frequency is tuned close to the resonance of the vibrational mode. The robustness of the quantum pump with temperature is also investigated and an exponential decay of the pumped charge is found when the coupling to the vibrational mode is present. Implications of our results for nano-electromechanical systems are also discussed.

C. A. Perroni; F. Romeo; A. Nocera; V. Marigliano Ramaglia; R. Citro; V. Cataudella

2014-04-16T23:59:59.000Z

469

A microfluidic device to sort capsules by deformability  

E-Print Network [OSTI]

Guided by extensive numerical simulations, we propose a microfluidic device that can sort elastic capsules by their deformability. The device consists of a duct embedded with a semi-cylindrical obstacle, and a diffuser which further enhances the sorting capability. We demonstrate that the device can operate reasonably well under changes in the initial position of the the capsule. The efficiency of the device remains essentially unaltered under small changes of the obstacle shape (from semi-circular to semi-elliptic cross-section). Confinement along the direction perpendicular to the plane of the device increases its efficiency. This work is the first numerical study of cell sorting by a realistic microfluidic device.

Zhu, L; Mitra, Dhrubaditya; Brandt, Luca

2014-01-01T23:59:59.000Z

470

Deformations of Quantum Symmetric Algebras Extended by Groups  

E-Print Network [OSTI]

algebra S(V ). Let G be a group acting linearly on V . If the action of G on V extends to all of Sq(V ), then the smash product algebra Sq(V )#G is obtained by using Sq(V ) kG as a vector space but with a new multiplication given by (a#g)(b#h) = a g...(b) # gh for all a; b 2 Sq(V ); g; h 2 G: For further details, see De nition II.29 and Example II.31. Graded Hecke algebras, also known as Drinfeld Hecke algebras [9], can be viewed as deformations of S(V )#G of type (T (V )#G) = (wiwj wjwi X g2G...

Shakalli Tang, Jeanette

2012-07-16T23:59:59.000Z

471

Multiphase Fluid Flow in Deformable Variable-Aperture Fractures - Final Report  

SciTech Connect (OSTI)

Fractures provide flow paths that can potentially lead to fast migration of fluids or contaminants. A number of energy-­?related applications involve fluid injections that significantly perturb both the pressures and chemical composition of subsurface fluids. These perturbations can cause both mechanical deformation and chemical alteration of host rocks with potential for significant changes in permeability. In fractured rock subjected to coupled chemical and mechanical stresses, it can be difficult to predict the sign of permeability changes, let alone the magnitude. This project integrated experimental and computational studies to improve mechanistic understanding of these coupled processes and develop and test predictive models and monitoring techniques. The project involved three major components: (1) study of two-­?phase flow processes involving mass transfer between phases and dissolution of minerals along fracture surfaces (Detwiler et al., 2009; Detwiler, 2010); (2) study of fracture dissolution in fractures subjected to normal stresses using experimental techniques (Ameli, et al., 2013; Elkhoury et al., 2013; Elkhoury et al., 2014) and newly developed computational models (Ameli, et al., 2014); (3) evaluation of electrical resistivity tomography (ERT) as a method to detect and quantify gas leakage through a fractured caprock (Breen et al., 2012; Lochbuhler et al., 2014). The project provided support for one PhD student (Dr. Pasha Ameli; 2009-­?2013) and partially supported a post-­?doctoral scholar (Dr. Jean Elkhoury; 2010-­?2013). In addition, the project provided supplemental funding to support collaboration with Dr. Charles Carrigan at Lawrence Livermore National Laboratory in connection with (3) and supported one MS student (Stephen Breen; 2011-­?2013). Major results from each component of the project include the following: (1) Mineral dissolution in fractures occupied by two fluid phases (e.g., oil-­?water or water-­?CO{sub 2}) causes changes in local capillary forces and redistribution of fluids. These coupled processes enhance channel formation and the potential for development of fast flow paths through fractures. (2) Dissolution in fractures subjected to normal stress can result in behaviors ranging from development of dissolution channels and rapid permeability increases to fracture healing and significant permeability decreases. The timescales associated with advective transport of dissolved ions in the fracture, mineral dissolution rates, and diffusion within the adjacent porous matrix dictate the sign and magnitude of the resulting permeability changes. Furthermore, a high-­? resolution mechanistic model that couples elastic deformation of contacts and aperture-­?dependent dissolution rates predicts the range of observed behaviors reasonably well. (3) ERT has potential as a tool for monitoring gas leakage in deep formations. Using probabilistic inversion methods further enhances the results by providing uncertainty estimates of inverted parameters.

Detwiler, Russell

2014-04-30T23:59:59.000Z

472

Development and Clinical Evaluation of a Three-Dimensional Cone-Beam Computed Tomography Estimation Method Using a Deformation Field Map  

SciTech Connect (OSTI)

Purpose: To develop a three-dimensional (3D) cone-beam computed tomography (CBCT) estimation method using a deformation field map, and to evaluate and optimize the efficiency and accuracy of the method for use in the clinical setting. Methods and Materials: We propose a method to estimate patient CBCT images using prior information and a deformation model. Patients' previous CBCT data are used as the prior information, and the new CBCT volume to be estimated is considered as a deformation of the prior image volume. The deformation field map is solved by minimizing deformation energy and maintaining new projection data fidelity using a nonlinear conjugate gradient method. This method was implemented in 3D form using hardware acceleration and multi-resolution scheme, and it was evaluated for different scan angles, projection numbers, and scan directions using liver, lung, and prostate cancer patient data. The accuracy of the estimation was evaluated by comparing the organ volume difference and the similarity between estimated CBCT and the CBCT reconstructed from fully sampled projections. Results: Results showed that scan direction and number of projections do not have significant effects on the CBCT estimation accuracy. The total scan angle is the dominant factor affecting the accuracy of the CBCT estimation algorithm. Larger scan angles yield better estimation accuracy than smaller scan angles. Lung cancer patient data showed that the estimation error of the 3D lung tumor volume was reduced from 13.3% to 4.3% when the scan angle was increased from 60 Degree-Sign to 360 Degree-Sign using 57 projections. Conclusions: The proposed estimation method is applicable for 3D DTS, 3D CBCT, four-dimensional CBCT, and four-dimensional DTS image estimation. This method has the potential for significantly reducing the imaging dose and improving the image quality by removing the organ distortion artifacts and streak artifacts shown in images reconstructed by the conventional Feldkamp-Davis-Kress (FDK) algorithm.

Ren, Lei, E-mail: lren1@hfhs.org [Department of Radiation Oncology, Henry Ford Health System, Detroit, MI (United States); Chetty, Indrin J. [Department of Radiation Oncology, Henry Ford Health System, Detroit, MI (United States); Zhang Junan [Department of Radiation Oncology, Oregon Health and Science University, Portland, OR (United States); Jin Jianyue [Department of Radiation Oncology, Henry Ford Health System, Detroit, MI (United States); Wu, Q. Jackie; Yan Hui; Brizel, David M.; Lee, W. Robert [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Movsas, Benjamin [Department of Radiation Oncology, Henry Ford Health System, Detroit, MI (United States); Yin Fangfang [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States)

2012-04-01T23:59:59.000Z

473

Deformability-based red blood cell separation in deterministic lateral displacement devices - a simulation study  

E-Print Network [OSTI]

We show, via three-dimensional immersed-boundary-finite-element-lattice-Boltzmann simulations, that deformability-based red blood cell (RBC) separation in deterministic lateral displacement (DLD) devices is possible. This is due to the deformability-dependent lateral extension of RBCs and enables us to predict a priori which RBCs will be displaced in a given DLD geometry. Several diseases affect the deformability of human cells. Malaria-infected RBCs or sickle cells, for example, tend to become stiffer than their healthy counterparts. It is therefore desirable to design microfluidic devices which can detect those diseases based on the cells' deformability fingerprint, rather than preparing samples using expensive and time-consuming biochemical preparation steps. Our findings should be helpful in the development of new methods for sorting cells and particles by deformability.

Timm Krueger; David Holmes; Peter V. Coveney

2014-06-07T23:59:59.000Z

474

deForm: An interactive malleable surface for capturing 2.5D arbitrary objects, tools and touch  

E-Print Network [OSTI]

We introduce a novel input device, deForm, that supports 2.5D touch gestures, tangible tools, and arbitrary objects through real-time structured light scanning of a malleable surface of interaction. DeForm captures ...

Ishii, Hiroshi

475

International Conference on Ground Control in Mining SDPS for Windows: An Integrated Approach to Ground Deformation Prediction  

E-Print Network [OSTI]

deformation prediction techniques, for assessing mining impacts on surface structures and facilities of surface facility to be protected. The Surface Deformation Prediction Software System (SDPS consideration of active, as well as abandoned, mine operations. The damages attributed to this phenomenon

476

Modeling Elasto-Plastic Behavior of Polycrystalline Grain Structure of Steels at Mesoscopic Level  

E-Print Network [OSTI]

Modeling Elasto-Plastic Behavior of Polycrystalline Grain Structure of Steels at Mesoscopic Level. The constitutive model of crystal grains utilizes anisotropic elasticity and crystal plasticity. Commercially be considered macroscopically homogeneous. Elastic and rate independent plastic deformation modes are considered

Cizelj, Leon

477

Hybrid Genetic Optimization and Statistical Model-Based Approach for the Classification  

E-Print Network [OSTI]

Hybrid Genetic Optimization and Statistical Model-Based Approach for the Classification of Shadow original statistical classification method using a deformable template model separate natural objects man template, along admissible linear transformations, to take account shape variability. classification

Mignotte, Max

478

A continuum constitutive model for amorphous metallic materials  

E-Print Network [OSTI]

A finite-deformation, Coulomb-Mohr type constitutive theory for the elastic-viscoplastic response of pressure-sensitive and plastically-dilatant isotropic materials has been developed. The constitutive model has been ...

Su, Cheng, Ph. D. Massachusetts Institute of Technology

2007-01-01T23:59:59.000Z

479

Modeling-Computer Simulations At Long Valley Caldera Geothermal...  

Open Energy Info (EERE)

and components of two continuous GPS time series. Additionally, the model explains the spatial extent of deformation observed by InSAR data covering the 1997-98 inflation...

480

Analytical modeling of composite steel-concrete frame systems  

E-Print Network [OSTI]

of reinforced concrete or composite steel shapes encased in reinforced concrete (SRC), structural steel beams, and composite beam-column joints. To facilitate the modeling of inelastic deformations in joint regions, a panel element capable of representing joint...

Atahan, Ali Osman

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "viscoelastic deformation model" from the National Library of EnergyBeta (NLEBeta).
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481

Transient Analysis for the Multimechanism-Deformation Parameters of Several Domal Salts  

SciTech Connect (OSTI)

Use of Gulf Coast salt domes for construction of very large storage caverns by solution mining has grown significantly in the last several decades. In fact, a nationally important Strategic Petroleum Reserve (SPR) storage occurs in large cavern arrays in some of these domes. Although caverns have been operated economically for these many years, these caverns have a range of relatively poorly understood behaviors, involving creep closure fluid loss and damage from salt falls. It is certainly possible to postulate that many of these behaviors stem from geomechanical or deformational aspects of the salt response. As a result, a method of correlating the cavern response to mechanical creep behavior as determined in the laboratory could be of considerable importance. Recently, detailed study of the creep response of domal salts has cast some insight into the influence of different salt origins on cavern behavior. The study used a simple graphical analysis of the limited non-steady state data to give a bound, or an approach to steady state, as an estimate of the steady state behavior of a given domal salt. This permitted the analysis of sparse creep databases for domal salts. It appears that a shortcoming of the steady state analysis was in masking some of the salt material differences. In an attempt to overcome the steady state analysis shortcomings, a method was developed based on the integration of the Multimechanism-Deformation (M-D) creep constitutive model to fit the transient response. This integration process essentially permits definition of the material sensitive parameters of the model, while those parameters that are either constants or material insensitive parameters are fixed independently. The transient analysis method has proven more sensitive to differences in the creep characteristics and has provided a way of defining different behaviors within a given dome. Creep characteristics, as defined by the transient analysis of the creep rate, are related quantitatively to the volume loss creep rate of the caverns. This type of understanding of the domal material creep response already has pointed to the possibility of establishing various distinct material spines within a given dome. Furthermore, if the creep databases for domal salts can be expanded, one could expect additional definition of domal geology and structure.

Munson, Darrell E.

1999-08-16T23:59:59.000Z

482

Proton-neutron pairing correlations in the nuclear shell model  

E-Print Network [OSTI]

A shell-model study of proton-neutron pairing in f - p shell nuclei using a parametrized hamiltonian that includes deformation and spin-orbit effects as well as isoscalar and isovector pairing is reported. By working in a shell-model framework we are able to assess the role of the various modes of proton-neutron pairing in the presence of nuclear deformation without violating symmetries. Results are presented for $^{44}$Ti, $^{46}$Ti and $^{48}$Cr.

Lei Yang; S. Pittel; B. Thakur; N. Sandulescu; A. Poves; Yu-Min Zhao

2010-06-16T23:59:59.000Z

483

Deformation of evaporites near the Waste Isolation Pilot Plant (WIPP) site  

SciTech Connect (OSTI)

Layered evaporite units of Ochoan age in the Delaware Basin are 1000 m thick. They are divided into three stratigraphic units (listed in order of increasing age): the Rustler Formation, the Salado Formation, the Castile Formation. These units, especially the Castile, are deformed along portions of the margin of the Delaware Basin and in some areas internal to the basin. Hypotheses of origin of deformation considered are: gravity foundering; gravity sliding; gypsum dehydration; dissolution; and depositional variations. Gravity foundering and sliding are considered the most probable causes of deformation. However, no hypothesis adequately answers why the deformation has a limited areal distribution. A possible explanation would be areal variations in rock strength caused by variations of intergranular water content. Age and timing of deformation are also crucial. Standard stratigraphic arguments based on superposition may not apply to such a highly incompetent material as halite. Gravity foundering could have happened at any time since deposition including the present; gravity sliding would probably have occurred since basin tilting began in the Cenozoic. Deformation could be ongoing. However, the strain rates are such (10/sup -16/ s/sup -1/) that deformation would progress slowly relative to the facility's time frame of 2.5 x 10/sup 5/ y. Deformation of Salado units would be minimal (<10 m) or nonexistent, but within this time frame, upper anhydrite units of the Castile could fracture and provide the volume for a brine reservoir. Such Volumes would be small (<1%) and would require 10/sup 4/ to 10/sup 6/ y to develop. At these strain rates, fractures that connect the fractured anhydrites of the Castile with the middle Salado could not develop. Deformation should not directly jeopardize the facility over the next 2.5 x 10/sup 5/ y.

Borns, D.J.; Barrows, L.J.; Powers, D.W.; Snyder, R.P.

1983-03-01T23:59:59.000Z

484

Estimation of deformation and stiffness of fractures close to tunnels using data from single-hole hydraulic testing and grouting  

SciTech Connect (OSTI)

Sealing of tunnels in fractured rocks is commonly performed by pre- or post-excavation grouting. The grouting boreholes are frequently drilled close to the tunnel wall, an area where rock stresses can be low and fractures can more easily open up during grout pressurization. In this paper we suggest that data from hydraulic testing and grouting can be used to identify grout-induced fracture opening, to estimate fracture stiffness of such fractures, and to evaluate its impact on the grout performance. A conceptual model and a method are presented for estimating fracture stiffness. The method is demonstrated using grouting data from four pre-excavation grouting boreholes at a shallow tunnel (50 m) in Nygard, Sweden, and two post-excavation grouting boreholes at a deep tunnel (450 m) in Aespoe HRL, Sweden. The estimated stiffness of intersecting fractures for the boreholes at the shallow Nygard tunnel are low (2-5 GPa/m) and in agreement with literature data from field experiments at other fractured rock sites. Higher stiffness was obtained for the deeper tunnel boreholes at Aespoe which is reasonable considering that generally higher rock stresses are expected at greater depths. Our method of identifying and evaluating the properties and impact of deforming fractures might be most applicable when grouting takes place in boreholes adjacent to the tunnel wall, where local stresses might be low and where deforming (opening) fractures may take most of the grout.

Fransson, A.; Tsang, C.-F.; Rutqvist, J.; Gustafson, G.

2010-05-01T23:59:59.000Z

485

Role of material properties and mesostructure on dynamic deformation and shear instability in Al-W granular composites  

E-Print Network [OSTI]

Dynamic experiments with Al-W granular/porous composites revealed qualitatively different behavior with respect to shear localization depending on bonding between Al particles. Two-dimensional numerical modeling was used to explore the mesomechanics of the large strain dynamic deformation in Al-W granular/porous composites and explain the experimentally observed differences in shear localization between composites with various mesostructures. Specifically, the bonding between the Al particles, the porosity, the roles of the relative particle sizes of Al and W, the arrangements of the W particles, and the material properties of Al were investigated using numerical calculations. It was demonstrated in simulations that the bonding between the "soft" Al particles facilitated shear localization as seen in the experiments. Numerical calculations and experiments revealed that the mechanism of the shear localization in granular composites is mainly due to the local high strain flow of "soft" Al around the "rigid" W particles causing localized damage accumulation and subsequent growth of the meso/macro shear bands/cracks. The "rigid" W particles were the major geometrical factor determining the initiation and propagation of "kinked" shear bands in the matrix of "soft" Al particles, leaving some areas free of extensive plastic deformation as observed in experiments and numerical calculations.

K. L. Olney; P. H. Chiu; C. W. Lee; V. F. Nesterenko; D. J. Benson

2011-05-24T23:59:59.000Z

486

3.22 Mechanical Properties of Materials, Spring 2003  

E-Print Network [OSTI]

Phenomenology of mechanical behavior of materials at the macroscopic level. Relationship of mechanical behavior to material structure and mechanisms of deformation and failure. Topics include: elasticity, viscoelasticity, ...

Gibson, Lorna J.

487

Chiral low-energy physics from squashed branes in deformed ${\\cal N}=4$ SYM  

E-Print Network [OSTI]

We discuss the low-energy physics which arises on stacks of squashed brane solutions of $SU(N)$ ${\\cal N}=4$ SYM, deformed by a cubic soft SUSY breaking potential. A brane configuration is found which leads to a low-energy physics similar to the standard model in the broken phase, assuming suitable VEV's of the scalar zero modes. Due to the triple self-intersection of the branes, the matter content includes that of the MSSM with precisely 3 generations and right-handed neutrinos. No exotic quantum numbers arise, however there are extra chiral superfields with the quantum numbers of the Higgs doublets, the $W,Z$, $e_R$ and $u_R$, whose fate depends on the details of the rich Higgs sector. The chiral low-energy sector is complemented by a heavy mirror sector with the opposite chiralities, as well as super-massive Kaluza-Klein towers completing the ${\\cal N}=4$ multiplets. The sectors are protected by two gauged global $U(1)$ symmetries.

Steinacker, Harold C

2015-01-01T23:59:59.000Z

488

The uses of the refined matrix model recursion  

E-Print Network [OSTI]

We study matrix models in the beta ensemble by building on the refined recursion relation proposed by Chekhov and Eynard. We present explicit results for the first beta-deformed corrections in the one-cut and the two-cut cases, as well as two applications to supersymmetric gauge theories: the calculation of superpotentials in N=1 gauge theories, and the calculation of vevs of surface operators in superconformal N=2 theories and their Liouville duals. Finally, we study the beta deformation of the Chern-Simons matrix model. Our results indicate that this model does not provide an appropriate description of the Omega-deformed topological string on the resolved conifold, and therefore that the beta-deformation might provide a different generalization of topological string theory in toric Calabi-Yau backgrounds.

Andrea Brini; Marcos Marino; Sebastien Stevan

2014-06-11T23:59:59.000Z

489

Evaluation of the filler effects on fatique cracking and permanent deformation of asphalt concrete mixtures  

E-Print Network [OSTI]

The addition of hydrated lime to asphalt has shown to be beneficial with an improvement in the Theological properties of the binder, as well as resistance to permanent deformation (rutting) and fatigue cracking of asphalt concrete mixtures...

Izzo, Richard P

1997-01-01T23:59:59.000Z

490

Study of permanent deformation mechanism in asphalt mixes in relation to microcrack growth  

E-Print Network [OSTI]

Recent developments by Lytton et al. (1998) indicate phics. that the growth of micrographs in asphalt layers under repeated loading is also a cause for the accumulation of permanent deformation or rutting in pavements besides the plastic strain...

Bhairampally, Rajesh Kumar

1998-01-01T23:59:59.000Z

491

Influence of specimen design on the deformation and failure of zircaloy cladding  

SciTech Connect (OSTI)

Experimental as well as computational analyses have been used to examine the deformation and failure behavior of ring-stretch specimens of Zircaloy-4 cladding tubes. The results show that, at least for plastically anisotropic unirradiated cladding, specimens with a small gauge length l to width w ratio (l/w {approx} 1) exhibit pronounced non-uniform deformation along their length. As a result, specimen necking occurs upon yielding when the specimen is fully plastic. Finite element analysis indicates a minimum l/w of 4 before a significant fraction of the gauge length deforms homogeneously. A brief examination of the contrasting deformation and failure behavior between uniaxial and plane-strain ring tension tests further supports the use of the latter geometry for determining cladding failure ductility data that are relevant to certain reactivity-initiated accident conditions.

Bates, D. W.; Koss, D. A.; Motta, A. T.; Majumdar S.

2000-02-17T23:59:59.000Z

492

Dynamical deformation effects in subbarrier fusion of $^{64}$Ni+$^{132}$Sn  

E-Print Network [OSTI]

We show that dynamical deformation effects play an important role in fusion reactions involving the $^{64}$Ni nucleus, in particular the $^{64}$Ni+$^{132}$Sn system. We calculate fully microscopic interaction potentials and the corresponding subbarrier fusion cross sections.

A. S. Umar; V. E. Oberacker

2006-09-25T23:59:59.000Z

493

Deformation of acoustically transparent fluid interfaces by the acoustic radiation pressure  

E-Print Network [OSTI]

in v/c, (v is the fluid velocity amplitude, c the sound speed), the time-averaged Lagrangian pressure.g., Rayleigh-Taylor) Abstract ­ We experimentally study the deformations of liquid-liquid interfaces induced

Paris-Sud XI, Université de

494

Method of deforming a biaxially textured buffer layer on a textured metallic substrate and articles therefrom  

DOE Patents [OSTI]

The present invention provides methods and biaxially textured articles having a deformed epitaxial layer formed therefrom for use with high temperature superconductors, photovoltaic, ferroelectric, or optical devices. A buffer layer is epitaxially deposited onto biaxially-textured substrates and then mechanically deformed. The deformation process minimizes or eliminates grooves, or other irregularities, formed on the buffer layer while maintaining the biaxial texture of the buffer layer. Advantageously, the biaxial texture of the buffer layer is not altered during subsequent heat treatments of the deformed buffer. The present invention provides mechanical densification procedures which can be incorporated into the processing of superconducting films through the powder deposit or precursor approaches without incurring unfavorable high-angle grain boundaries.

Lee, Dominic F. (Knoxville, TN); Kroeger, Donald M. (Knoxville, TN); Goyal, Amit (Knoxville, TN)

2000-01-01T23:59:59.000Z

495

INTEGRATED INSAR AND GPS STUDIES OF CRUSTAL DEFORMATION IN THE WESTERN GREAT BASIN, WESTERN UNITED STATES  

E-Print Network [OSTI]

UK - Zhenhong.Li@ges.gla.ac.uk KEY WORDS: InSAR, GPS, crustal deformation, Yucca Mountain, vertical GPS networks which are limited by their station spacing. We select the Yucca Mountain, Nevada region

Tingley, Joseph V.

496

Nuclear fusion as a probe for octupole deformation in $^{224}$Ra  

E-Print Network [OSTI]

$\\textit{Background}$: Nuclear fusion has been shown to be a perfect probe to study the different nuclear shapes. However, the possibility of testing octupole deformation of a nucleus with this tool has not been fully explored yet. The presence of a stactic octupole deformation in nuclei will enhanced a possible permanent electric dipole moment, leading to a possible demonstration of parity violation. $\\textit{Purpose}$: To check whether static octupole deformation or octupole vibration in fusion give qualitatively different results so that both situations can be experimentally disentangled. $\\textit{Method}$: Fusion cross sections are computed in the Coupled-Channels formalism making use of the Ingoing-Wave Boundary Conditions (IWBC) for the systems $^{16}$O+$^{144}$Ba and $^{16}$O+$^{224}$Ra. $\\textit{Results}$: Barrier distributions of the two considered schemes show different patterns. For the $^{224}$Ra case, the octupole deformation parameter is large enough to create a sizeable difference. $\\textit{Con...

Kumar, Raj; Vitturi, A

2015-01-01T23:59:59.000Z

497

Fermi-Energy-Dependent Structural Deformation of Chiral Single-Wall Carbon Nanotubes  

E-Print Network [OSTI]

In this work, we use an extended tight-binding approach for calculating the Fermi-energy dependence of the structural deformation of chiral single-wall carbon nanotubes (SWNTs). We show that, in general, nanotube strains ...

Vieira, Bruno G.?M.

498

On Coating Durability of Polymer Coated Sheet Metal under Plastic Deformation  

E-Print Network [OSTI]

process. Thus, the effect of plastic deformation on coating adhesion is of primary interest to many engineers and researchers. This research aims at developing a methodology to predict the adhesion of coating after metal forming processes. A pull...

Huang, Yu-Hsuan

2011-08-08T23:59:59.000Z

499

Formation of bands and ridges on Europa by cyclic deformation: Insights from analogue wax experiments  

E-Print Network [OSTI]

, California, USA Antoine Sinton Departement des Sciences de la Matiere, Ecole Normale Superieure, Lyon, France); KEYWORDS: Europa, ridges, tidal deformation Citation: Manga, M., and A. Sinton (2004), Formation of bands

Manga, Michael

500

Controllable Conformal Maps for Shape Deformation and Interpolation Ofir Weber Craig Gotsman  

E-Print Network [OSTI]

Controllable Conformal Maps for Shape Deformation and Interpolation Ofir Weber Craig Gotsman Technion ­ Israel Institute of Technology weber@cs.technion.ac.il gotsman@cs.technion.ac.il Figure 1

Gotsman, Craig