Multipole matrix elements of Green function of Laplace equation
Karol Makuch; Przemys?aw Górka
2015-01-02T23:59:59.000Z
Multipole matrix elements of Green function of Laplace equation are calculated. The multipole matrix elements of Green function in electrostatics describe potential on a sphere which is produced by a charge distributed on the surface of a different (possibly overlapping) sphere of the same radius. The matrix elements are defined by double convolution of two spherical harmonics with the Green function of Laplace equation. The method we use relies on the fact that in the Fourier space the double convolution has simple form. Therefore we calculate the multipole matrix from its Fourier transform. An important part of our considerations is simplification of the three dimensional Fourier transformation of general multipole matrix by its rotational symmetry to the one-dimensional Hankel transformation.
Three-dimensional nonlinear Schroedinger equation in electron-positron-ion magnetoplasmas
Sabry, R. [Department of Physics, College of Science and Humanitarian Studies, Alkharj University, Alkharj 11942 (Saudi Arabia); Department of Physics, Theoretical Physics Group, Faculty of Science, Mansoura University, Damietta-Branch, New Damietta, 34517 Damietta (Egypt); Moslem, W. M. [Department of Physics, Faculty of Science, Port Said University, Port Said (Egypt); El-Shamy, E. F. [Department of Physics, Theoretical Physics Group, Faculty of Science, Mansoura University, Damietta-Branch, New Damietta, 34517 Damietta (Egypt); Shukla, P. K. [RUB International Chair, Faculty of Physics and Astronomy, International Centre for Advanced Studies in Physical Sciences, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)
2011-03-15T23:59:59.000Z
Three-dimensional ion-acoustic envelope soliton excitations in electron-positron-ion magnetoplasmas are interpreted. This is accomplished through the derivation of three-dimensional nonlinear Schroedinger equation, where the nonlinearity is balancing with the dispersive terms. The latter contains both an external magnetic field besides the usual plasma parameter effects. Based on the balance between the nonlinearity and the dispersion terms, the regions for possible envelope solitons are investigated indicating that new regimes for modulational instability of envelope ion-acoustic waves could be obtained, which cannot exist in the unmagnetized case. This will allow us to establish additional new regimes, different from the usual unmagnetized plasma, for envelope ion-acoustic waves to propagate in multicomponent plasma that may be observed in space or astrophysics.
Laplace Operators on Fractals and Related Functional Equations
Gregory Derfel; Peter Grabner; Fritz Vogl
2012-06-06T23:59:59.000Z
We give an overview over the application of functional equations, namely the classical Poincar\\'e and renewal equations, to the study of the spectrum of Laplace operators on self-similar fractals. We compare the techniques used to those used in the euclidean situation. Furthermore, we use the obtained information on the spectral zeta function to define the Casimir energy of fractals. We give numerical values for this energy for the Sierpi\\'nski gasket.
Karsilayan, Nur
2011-08-08T23:59:59.000Z
FULL-WAVE SURFACE INTEGRAL EQUATION METHOD FOR ELECTROMAGNETIC-CIRCUIT SIMULATION OF THREE-DIMENSIONAL INTERCONNECTS IN LAYERED MEDIA A Dissertation by NUR KURT KARSILAYAN Submitted to the Office of Graduate Studies of Texas A&M University... in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY May 2010 Major Subject: Electrical Engineering FULL-WAVE SURFACE INTEGRAL EQUATION METHOD FOR ELECTROMAGNETIC-CIRCUIT SIMULATION OF THREE-DIMENSIONAL INTERCONNECTS...
Waltz, J., E-mail: jwaltz@lanl.gov [Computational Physics Division, Los Alamos National Laboratory, Los Alamos, NM (United States); Canfield, T.R. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM (United States); Morgan, N.R. [Computational Physics Division, Los Alamos National Laboratory, Los Alamos, NM (United States); Risinger, L.D.; Wohlbier, J.G. [Computational and Computer Sciences Division, Los Alamos National Laboratory, Los Alamos, NM (United States)
2014-06-15T23:59:59.000Z
We present a set of manufactured solutions for the three-dimensional (3D) Euler equations. The purpose of these solutions is to allow for code verification against true 3D flows with physical relevance, as opposed to 3D simulations of lower-dimensional problems or manufactured solutions that lack physical relevance. Of particular interest are solutions with relevance to Inertial Confinement Fusion (ICF) capsules. While ICF capsules are designed for spherical symmetry, they are hypothesized to become highly 3D at late time due to phenomena such as Rayleigh–Taylor instability, drive asymmetry, and vortex decay. ICF capsules also involve highly nonlinear coupling between the fluid dynamics and other physics, such as radiation transport and thermonuclear fusion. The manufactured solutions we present are specifically designed to test the terms and couplings in the Euler equations that are relevant to these phenomena. Example numerical results generated with a 3D Finite Element hydrodynamics code are presented, including mesh convergence studies.
A Bme Solution Of The Stochastic Three-Dimensional Laplace Equation...
model of the geothermal field in the Nea Kessani region (Greece) by means of the Bayesian maximum entropy (BME) method, which describes the temperature variations across space in...
A Bme Solution Of The Stochastic Three-Dimensional Laplace Equation
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The quintic nonlinear Schr\\"odinger equation on three-dimensional Zoll manifolds
Herr, Sebastian
2011-01-01T23:59:59.000Z
Let (M,g) be a three-dimensional smooth compact Riemannian manifold such that all geodesics are simple and closed with a common minimal period, such as the 3-sphere S^3 with canonical metric. In this work the global well-posedness problem for the quintic nonlinear Schr\\"odinger equation i\\partial_t u+\\Delta u=\\pm|u|^4u, u|_{t=0}=u_0 is solved for small initial data u_0 in the energy space H^1(M), which is the scaling-critical space. Moreover, local well-posedness is shown for large data, as well as persistence of higher initial Sobolev regularity. This extends previous results of Burq-G\\'erard-Tzvetkov to the endpoint case.
A three dimensional corner balance method for spatial discretization of the transport equation
Richardson, Rebecca Lynn
1994-01-01T23:59:59.000Z
discretization. NUMERICAL RESULTS Benchmark Problems The two dimensional corner balance method and the code SNAC have been extensively tested. For the purposes of this project, it was assumed that two dimensonal results produced by SNAC are correct... OF SCIENCE Approved as to style and content by: Marvin Adams (Chair of Committee) aytcho Lazarov (Member) Paul Nelson (Member) Joh W. Poston (Head of Department) May 1994 Major Subject: Nuclear Engineering ABSTRACT A Three Dimensional Corner...
Three-dimensional h-adaptivity for the multigroup neutron diffusion equations Yaqi Wang a
Bangerth, Wolfgang
(Bell and Glasstone, 1970; Duderstadt and Martin, 1979), an equation that is extraordinarily complicated
Kasahara, Kento [Department of Molecular Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510 (Japan); Sato, Hirofumi, E-mail: hirofumi@moleng.kyoto-u.ac.jp [Department of Molecular Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510 (Japan); Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Nishikyo-ku, Kyoto 615-8510 (Japan)
2014-06-28T23:59:59.000Z
Site-site Smoluchowski-Vlasov (SSSV) equation enables us to directly calculate van Hove time correlation function, which describes diffusion process in molecular liquids. Recently, the theory had been extended to treat solute-solvent system by Iida and Sato [J. Chem. Phys. 137, 034506 (2012)]. Because the original framework of SSSV equation is based on conventional pair correlation function, time evolution of system is expressed in terms of one-dimensional solvation structure. Here, we propose a new SSSV equation to calculate time evolution of solvation structure in three-dimensional space. The proposed theory was applied to analyze diffusion processes in 1M NaCl aqueous solution and in lithium ion battery electrolyte solution. The results demonstrate that these processes are properly described with the theory, and the computed van Hove functions are in good agreement with those in previous works.
Why Professor Richard Feynman was upset solving the Laplace equation for spherical waves?
Anzor Khelashvili; Teimuraz Nadareishvili
2013-02-04T23:59:59.000Z
We take attention to the singular behavior of the Laplace operator in spherical coordinates, which was established in our earlier work. This singularity has many non-trivial consequences. In this article we consider only the simplest ones, which are connected to the solution of Laplace equation in Feynman classical books and Lectures. Feynman was upset looking in his derived solutions, which have a fictitious singular behavior at the origin. We show how these inconsistencies can be avoided.
A Lagrangian analysis of advection-diffusion equation for a three dimensional chaotic flow
Tang, X.Z. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Boozer, A.H. [Department of Applied Physics, Columbia University, New York, New York 10027 (United States)] [Department of Applied Physics, Columbia University, New York, New York 10027 (United States); [Max-Planck Institut fuer Plasmaphysik, Garching (Germany)
1999-06-01T23:59:59.000Z
The advection-diffusion equation is studied via a global Lagrangian coordinate transformation. The metric tensor of the Lagrangian coordinates couples the dynamical system theory rigorously into the solution of this class of partial differential equations. If the flow has chaotic streamlines, the diffusion will dominate the solution at a critical time, which scales logarithmically with the diffusivity. The subsequent rapid diffusive relaxation is completed on the order of a few Lyapunov times, and it becomes more anisotropic the smaller the diffusivity. The local Lyapunov time of the flow is the inverse of the finite time Lyapunov exponent. A finite time Lyapunov exponent can be expressed in terms of two convergence functions which are responsible for the spatio-temporal complexity of both the advective and diffusive transports. This complexity gives a new class of diffusion barrier in the chaotic region and a fractal-like behavior in both space and time. In an integrable flow with shear, there also exist fast and slow diffusion. But unlike that in a chaotic flow, a large gradient of the scalar field across the KAM surfaces can be maintained since the fast diffusion in an integrable flow is strictly confined within the KAM surfaces. {copyright} {ital 1999 American Institute of Physics.}
Morales, Mayckol; Herrera, William J
2015-01-01T23:59:59.000Z
We find solutions of Laplace's equation with specific boundary conditions (in which such solutions take either the value zero or unity in each surface) using a generic curvilinear system of coordinates. Such purely geometrical solutions (that we shall call Basic Harmonic Functions BHF's) are utilized to obtain a more general class of solutions for Laplace's equation, in which the functions take arbitrary constant values on the boundaries. On the other hand, the BHF's are also used to obtain the capacitance of many electrostatic configurations of conductors. This method of finding solutions of Laplace's equation and capacitances with multiple symmetries is particularly simple, owing to the fact that the method of separation of variables becomes much simpler under the boundary conditions that lead to the BHF's. Examples of application in complex symmetries are given. Then, configurations of succesive embedding of conductors are also examined. In addition, expressions for electric fields between two conductors a...
Solution of the space-time reactor kinetics equations using the method of Laplace transforms
Rottler, Jerry Stephen
1982-01-01T23:59:59.000Z
for the degree of MASTER OF SCIENCE December 1982 Major Subject: Nuclear Engineering SOLUTION OF THE SPACE-TIME REACTOR KINETICS EQUATIONS USING THE METHOD OF LAPLACE TRANSFORMS . A Thesis by JERRY STEPHEN ROTTLER Approved as to style and content by...gated in detail. ACKNOHLEDGEMENT The author would like to express gratitude to several individuals who made this work possible. First, he would like to thank his committee chairman, Dr. Clarence E. Lee, for suggesting this project and for his...
Tug-of-war and infinity Laplace equation with vanishing Neumann boundary condition
Antunovi?, Ton?i; Sheffield, Scott; Somersille, Stephanie
2011-01-01T23:59:59.000Z
We study a version of the stochastic "tug-of-war" game, played on graphs and smooth domains, with the empty set of terminal states. We prove that, when the running payoff function is shifted by an appropriate constant, the values of the game after n steps converge in the continuous case and the case of finite graphs with loops. Using this we prove the existence of solutions to the infinity Laplace equation with vanishing Neumann boundary condition.
Chien, T.H.; Domanus, H.M.; Sha, W.T.
1993-02-01T23:59:59.000Z
The COMMIX-PPC computer pregrain is an extended and improved version of earlier COMMIX codes and is specifically designed for evaluating the thermal performance of power plant condensers. The COMMIX codes are general-purpose computer programs for the analysis of fluid flow and heat transfer in complex Industrial systems. In COMMIX-PPC, two major features have been added to previously published COMMIX codes. One feature is the incorporation of one-dimensional equations of conservation of mass, momentum, and energy on the tube stile and the proper accounting for the thermal interaction between shell and tube side through the porous-medium approach. The other added feature is the extension of the three-dimensional conservation equations for shell-side flow to treat the flow of a multicomponent medium. COMMIX-PPC is designed to perform steady-state and transient. Three-dimensional analysis of fluid flow with heat transfer tn a power plant condenser. However, the code is designed in a generalized fashion so that, with some modification, it can be used to analyze processes in any heat exchanger or other single-phase engineering applications. Volume I (Equations and Numerics) of this report describes in detail the basic equations, formulation, solution procedures, and models for a phenomena. Volume II (User`s Guide and Manual) contains the input instruction, flow charts, sample problems, and descriptions of available options and boundary conditions.
Mark Chanachowicz; Claudia M. Chanu; Raymond G. McLenaghan
2007-11-13T23:59:59.000Z
An invariant characterization of the rotationally symmetric R-separable webs for the Laplace equation in Euclidean space is given in terms of invariants and covariants of a real binary quartic canonically associated to the characteristic conformal Killing tensor which defines the webs.
Oxley, Paul
Finite element solution of Laplace's equation for ion-atom chambers Jacob Golde, Janine Shertzer for ion-atom chambers. We first consider a simplified model chamber for which an analytical solution can is carried out in an ion-atom chamber. The atomic beam first passes through a region of the cham- ber where
Three-dimensional photovoltaics
Myers, Bryan
The concept of three-dimensional (3D) photovoltaics is explored computationally using a genetic algorithm to optimize the energy production in a day for arbitrarily shaped 3D solar cells confined to a given area footprint ...
Szilagyi, Jozsef
boundary conditions Jozsef Szilagyi Conservation and Survey Division, University of Nebraska analysis Citation: Szilagyi, J., Sensitivity analysis of aquifer parameter estimations based on the Laplace
Three-dimensional metamaterials
Burckel, David Bruce (Albuquerque, NM)
2012-06-12T23:59:59.000Z
A fabrication method is capable of creating canonical metamaterial structures arrayed in a three-dimensional geometry. The method uses a membrane suspended over a cavity with predefined pattern as a directional evaporation mask. Metallic and/or dielectric material can be evaporated at high vacuum through the patterned membrane to deposit resonator structures on the interior walls of the cavity, thereby providing a unit cell of micron-scale dimension. The method can produce volumetric metamaterial structures comprising layers of such unit cells of resonator structures.
Three-Dimensional Laser Cooling
Okamato, H.
2008-01-01T23:59:59.000Z
Three-Dimensional Laser Cooling H. Okamoto, A.M. Sessler,effective transverse laser cooling simultaneously withlongitudinal laser cooling, two possibilities are
Three dimensional colorimetric assay assemblies
Charych, Deborah (Albany, CA); Reichart, Anke (Albany, CA)
2000-01-01T23:59:59.000Z
A direct assay is described using novel three-dimensional polymeric assemblies which change from a blue to red color when exposed to an analyte, in one case a flu virus. The assemblies are typically in the form of liposomes which can be maintained in a suspension, and show great intensity in their color changes. Their method of production is also described.
Parallel finite element algorithm for three dimensional ...
methods for electromagnetic induction. INTRODUCTION. N umerical modelling of three dimensional conductivity structures in the earth has experienced a rapid ...
Well correction factors for three-dimensional reservoir simulation
Fjerstad, Paul Albert
1985-01-01T23:59:59.000Z
of Advisory Committee: Dr. W. D. Von Gonten A three-dimensional reservoir simulation model does not calculate the correct bottomhole flowing pressure, p f, for a partially penetrating well. The simulator well cell pressure must be corrected ro obtain... an accurate value for p f. Simulation model results have wf' been used in this part to develop a new inflow equation relating cell pressure to actual bottomhole flowing pressure for a partially penetrating well. Based on the new inflow equation, an equation...
Ewing, Richard E.
A ThreeDimensional Finite Element Simulation for Transport of Nuclear Waste Contamination of South Carolina, Columbia, South Carolina ABSTRACT: Model equations for transport of nuclearwaste based up on the inherent physics. A threedimensional finite element method for nuclear waste
Three-Dimensional Nonlinear Acoustical Holography
Niu, Yaying
2013-05-06T23:59:59.000Z
Nearfield Acoustical Holography (NAH) is an acoustic field visualization technique that can be used to reconstruct three-dimensional (3-D) acoustic fields by projecting two-dimensional (2-D) data measured on a hologram surface. However, linear NAH...
Dynamics of empty homogeneous isotropic three-dimensional spaces
A. V. Klimenko; V. A. Klimenko
2012-02-28T23:59:59.000Z
It is shown that there are seven types of solutions described in the framework of general relativity theory (GRT), the dynamics of empty homogeneous isotropic three-dimensional spaces. Solution of the equations of GRT, which describes the dynamics of a homogeneous isotropic universe, in the limiting case of vanishingly small effect of matter on the metric properties of space must go to one of them.
Boundary Integral Equations and the Method of Boundary Elements
Tsynkov, Semyon V.
to consider the interior and exterior Dirichlet and Neumann boundary value problems for the Laplace equation: u 2u x2 1 + 2u x2 2 + 2u x2 3 = 0. Let be a bounded domain of the three-dimensional space R3 and exterior Dirichlet problems, respectively, and problems (13.1b) and (13.1d) are the interior and exterior
Three-dimensional colorimetric assay assemblies
Charych, Deborah (Albany, CA); Reichert, Anke (Albany, CA)
2001-01-01T23:59:59.000Z
A direct assay is described using novel three-dimensional polymeric assemblies which change from a blue to red color when exposed to an analyte, in one case a flue virus. The assemblies are typically in the form of liposomes which can be maintained in a suspension, and show great intensity in their color changes. Their method of production is also described.
Creating a three dimensional holographic movie
Guerra, Marvin J
2008-01-01T23:59:59.000Z
An experimental study was carried out on the ability to create a three-dimensional holographic movie. Holograms were written on VRP-M emulsion film with the green line of an Argon-Ion laser. The type of hologram write setup ...
Real time three dimensional sensing system
Gordon, S.J.
1996-12-31T23:59:59.000Z
The invention is a three dimensional sensing system which utilizes two flexibly located cameras for receiving and recording visual information with respect to a sensed object illuminated by a series of light planes. Each pixel of each image is converted to a digital word and the words are grouped into stripes, each stripe comprising contiguous pixels. One pixel of each stripe in one image is selected and an epi-polar line of that point is drawn in the other image. The three dimensional coordinate of each selected point is determined by determining the point on said epi-polar line which also lies on a stripe in the second image and which is closest to a known light plane. 7 figs.
Real time three dimensional sensing system
Gordon, Steven J. (Boston, MA)
1996-01-01T23:59:59.000Z
The invention is a three dimensional sensing system which utilizes two flexibly located cameras for receiving and recording visual information with respect to a sensed object illuminated by a series of light planes. Each pixel of each image is converted to a digital word and the words are grouped into stripes, each stripe comprising contiguous pixels. One pixel of each stripe in one image is selected and an epi-polar line of that point is drawn in the other image. The three dimensional coordinate of each selected point is determined by determining the point on said epi-polar line which also lies on a stripe in the second image and which is closest to a known light plane.
Three dimensional digital imaging of environmental data
Nichols, R.L.; Eddy, C.A.
1991-06-14T23:59:59.000Z
The Environmental Sciences Section (ESS) of the Savannah River Laboratory has recently acquired the computer hardware (Silicon Graphics Personal Iris Workstations) and software (Dynamic Graphics, Interactive Surface and Volume Modeling) to perform three dimensional analysis of hydrogeologic data. Three dimensional digital imaging of environmental data is a powerful technique that can be used to incorporate field, analytical, and modeling results from geologic, hydrologic, ecologic, and chemical studies into a comprehensive model for visualization and interpretation. This report covers the contamination of four different sites of the Savannah River Plant. Each section of this report has a computer graphic display of the concentration of contamination in the groundwater and/or sediments of each site.
Three-dimensional display of document set
Lantrip, David B. (Oxnard, CA); Pennock, Kelly A. (Richland, WA); Pottier, Marc C. (Richland, WA); Schur, Anne (Richland, WA); Thomas, James J. (Richland, WA); Wise, James A. (Richland, WA)
2006-09-26T23:59:59.000Z
A method for spatializing text content for enhanced visual browsing and analysis. The invention is applied to large text document corpora such as digital libraries, regulations and procedures, archived reports, and the like. The text content from these sources may e transformed to a spatial representation that preserves informational characteristics from the documents. The three-dimensional representation may then be visually browsed and analyzed in ways that avoid language processing and that reduce the analysts' effort.
Three-dimensional display of document set
Lantrip, David B. (Oxnard, CA); Pennock, Kelly A. (Richland, WA); Pottier, Marc C. (Richland, WA); Schur, Anne (Richland, WA); Thomas, James J. (Richland, WA); Wise, James A. (Richland, WA); York, Jeremy (Bothell, WA)
2009-06-30T23:59:59.000Z
A method for spatializing text content for enhanced visual browsing and analysis. The invention is applied to large text document corpora such as digital libraries, regulations and procedures, archived reports, and the like. The text content from these sources may be transformed to a spatial representation that preserves informational characteristics from the documents. The three-dimensional representation may then be visually browsed and analyzed in ways that avoid language processing and that reduce the analysts' effort.
Three-Dimensional Magnetohydrodynamic Simulation of Slapper Initiation Systems
Christensen, J S; Hrousis, C A
2010-03-09T23:59:59.000Z
Although useful information can be gleaned from 2D and even 1D simulations of slapper type initiation systems, these systems are inherently three-dimensional and therefore require full 3D representation to model all relevant details. Further, such representation provides additional insight into optimizing the design of such devices from a first-principles perspective and can thereby reduce experimental costs. We discuss in this paper several ongoing efforts in modeling these systems, our pursuit of validation, and extension of these methods to other systems. Our results show the substantial dependence upon highly accurate global equations of state and resistivity models in these analyses.
Heat pulse propagation in chaotic three-dimensional magnetic fields
Del-Castillo-Negrete, Diego [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Blazevski, Daniel [Institute for Mechanical Systems, ETH, Zurich (Switzerland)
2014-06-01T23:59:59.000Z
Heat pulse propagation in three-dimensional chaotic magnetic fields is studied by numerically solving the parallel heat transport equation using a Lagrangian Green's function (LG) method. The main two problems addressed are: the dependence of the radial transport of heat pulses on the level of magnetic field stochasticity (controlled by the amplitude of the magnetic field perturbation, ?), and the role of reversed shear magnetic field configurations on heat pulse propagation. The role of separatrix reconnection of resonant modes in the shear reversal region, and the role of shearless Cantori in the observed phenomena are also discussed.
Three-dimensional modeling of the plasma arc in arc welding
Xu, G.; Tsai, H. L. [Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, 1870 Miner Circle, Rolla, Missouri 65409 (United States); Hu, J. [Department of Mechanical Engineering, University of Bridgeport, Bridgeport, Connecticut 06604 (United States)
2008-11-15T23:59:59.000Z
Most previous three-dimensional modeling on gas tungsten arc welding (GTAW) and gas metal arc welding (GMAW) focuses on the weld pool dynamics and assumes the two-dimensional axisymmetric Gaussian distributions for plasma arc pressure and heat flux. In this article, a three-dimensional plasma arc model is developed, and the distributions of velocity, pressure, temperature, current density, and magnetic field of the plasma arc are calculated by solving the conservation equations of mass, momentum, and energy, as well as part of the Maxwell's equations. This three-dimensional model can be used to study the nonaxisymmetric plasma arc caused by external perturbations such as an external magnetic field. It also provides more accurate boundary conditions when modeling the weld pool dynamics. The present work lays a foundation for true three-dimensional comprehensive modeling of GTAW and GMAW including the plasma arc, weld pool, and/or electrode.
The Laplace Transform 1 Laplace transform and inverse transform
Yengulalp, Lynne
The Laplace Transform Name: 1 Laplace transform and inverse transform Definition. Let f(t) be a function defined for t 0. Then the integral L {f(t)} = 0 e-st f(t)dt is said to be the Laplace transform of f provided the integral converges. Fill in the following Laplace transforms. L {tn } = L {eat } = L
Sandia Energy - Three-Dimensional Graphene Architectures
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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del Sol Home Distribution GridDocumentsInstituteThree-Dimensional Graphene
Two component-three dimensional catalysis
Schwartz, Michael (Boulder, CO); White, James H. (Boulder, CO); Sammells, Anthony F. (Boulder, CO)
2002-01-01T23:59:59.000Z
This invention relates to catalytic reactor membranes having a gas-impermeable membrane for transport of oxygen anions. The membrane has an oxidation surface and a reduction surface. The membrane is coated on its oxidation surface with an adherent catalyst layer and is optionally coated on its reduction surface with a catalyst that promotes reduction of an oxygen-containing species (e.g., O.sub.2, NO.sub.2, SO.sub.2, etc.) to generate oxygen anions on the membrane. The reactor has an oxidation zone and a reduction zone separated by the membrane. A component of an oxygen containing gas in the reduction zone is reduced at the membrane and a reduced species in a reactant gas in the oxidation zone of the reactor is oxidized. The reactor optionally contains a three-dimensional catalyst in the oxidation zone. The adherent catalyst layer and the three-dimensional catalyst are selected to promote a desired oxidation reaction, particularly a partial oxidation of a hydrocarbon.
Three-dimensional Radiative Transfer with Multilevel Atoms
P. Fabiani Bendicho; J. Trujillo Bueno
2007-10-29T23:59:59.000Z
The efficient numerical solution of Non-LTE multilevel transfer problems requires the combination of highly convergent iterative schemes with fast and accurate formal solution methods of the radiative transfer (RT) equation. This contribution begins presenting a method for the formal solution of the RT equation in three-dimensional (3D) media with horizontal periodic boundary conditions. This formal solver is suitable for both, unpolarized and polarized 3D radiative transfer and it can be easily combined with the iterative schemes for solving non-LTE multilevel transfer problems that we have developed over the last few years. We demonstrate this by showing some schematic 3D multilevel calculations that illustrate the physical effects of horizontal radiative transfer. These Non-LTE calculations have been carried out with our code MUGA 3D, a 3D multilevel Non-LTE code based on the Gauss-Seidel iterative scheme that Trujillo Bueno and Fabiani Bendicho (1995) developed for RT applications.
Experimental and theoretical investigation of three-dimensional...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
theoretical investigation of three-dimensional nitrogen-doped aluminum clusters AI8N- and AI8N. Experimental and theoretical investigation of three-dimensional nitrogen-doped...
Numerical Simulation of Unsteady Three-Dimensional Sheet Cavitation
Twente, Universiteit
Numerical Simulation of Unsteady Three-Dimensional Sheet Cavitation A.H. Koop #12;Numerical Simulation of Unsteady Three-Dimensional Sheet Cavitation A.H. Koop Thesis University of Twente, Enschede, the Netherlands #12;NUMERICAL SIMULATION OF UNSTEADY THREE-DIMENSIONAL SHEET CAVITATION PROEFSCHRIFT ter
Three-dimensional tori and Arnold tongues
Sekikawa, Munehisa, E-mail: sekikawa@cc.utsunomiya-u.ac.jp [Department of Mechanical and Intelligent Engineering, Utsunomiya University, Utsunomiya-shi 321-8585 (Japan)] [Department of Mechanical and Intelligent Engineering, Utsunomiya University, Utsunomiya-shi 321-8585 (Japan); Inaba, Naohiko [Organization for the Strategic Coordination of Research and Intellectual Property, Meiji University, Kawasaki-shi 214-8571 (Japan)] [Organization for the Strategic Coordination of Research and Intellectual Property, Meiji University, Kawasaki-shi 214-8571 (Japan); Kamiyama, Kyohei [Department of Electronics and Bioinformatics, Meiji University, Kawasaki-shi 214-8571 (Japan)] [Department of Electronics and Bioinformatics, Meiji University, Kawasaki-shi 214-8571 (Japan); Aihara, Kazuyuki [Institute of Industrial Science, the University of Tokyo, Meguro-ku 153-8505 (Japan)] [Institute of Industrial Science, the University of Tokyo, Meguro-ku 153-8505 (Japan)
2014-03-15T23:59:59.000Z
This study analyzes an Arnold resonance web, which includes complicated quasi-periodic bifurcations, by conducting a Lyapunov analysis for a coupled delayed logistic map. The map can exhibit a two-dimensional invariant torus (IT), which corresponds to a three-dimensional torus in vector fields. Numerous one-dimensional invariant closed curves (ICCs), which correspond to two-dimensional tori in vector fields, exist in a very complicated but reasonable manner inside an IT-generating region. Periodic solutions emerge at the intersections of two different thin ICC-generating regions, which we call ICC-Arnold tongues, because all three independent-frequency components of the IT become rational at the intersections. Additionally, we observe a significant bifurcation structure where conventional Arnold tongues transit to ICC-Arnold tongues through a Neimark-Sacker bifurcation in the neighborhood of a quasi-periodic Hopf bifurcation (or a quasi-periodic Neimark-Sacker bifurcation) boundary.
Analytical Derivation of Three Dimensional Vorticity Function for wave breaking in Surf Zone
Dutta, R
2015-01-01T23:59:59.000Z
In this report, Mathematical model for generalized nonlinear three dimensional wave breaking equations was de- veloped analytically using fully nonlinear extended Boussinesq equations to encompass rotational dynamics in wave breaking zone. The three dimensional equations for vorticity distributions are developed from Reynold based stress equations. Vorticity transport equations are also developed for wave breaking zone. This equations are basic model tools for numerical simulation of surf zone to explain wave breaking phenomena. The model reproduces most of the dynamics in the surf zone. Non linearity for wave height predictions is also shown close to the breaking both in shoaling as well as surf zone. Keyword Wave breaking, Boussinesq equation, shallow water, surf zone. PACS : 47.32-y
Propagation of three-dimensional electron-acoustic solitary waves
Shalaby, M.; El-Sherif, L. S. [Faculty of Science, Department of Physics, Ain Shams University, Cairo (Egypt); El-Labany, S. K. [Theoretical Physics Group, Faculty of Science, Department of Physics, Mansoura University, Damietta Branch, New Damietta 34517 (Egypt); Sabry, R. [Theoretical Physics Group, Faculty of Science, Department of Physics, Mansoura University, Damietta Branch, New Damietta 34517 (Egypt); Physics Department, College of Science and Humanitarian Studies, Alkharj University, Alkharj (Saudi Arabia)
2011-06-15T23:59:59.000Z
Theoretical investigation is carried out for understanding the properties of three-dimensional electron-acoustic waves propagating in magnetized plasma whose constituents are cold magnetized electron fluid, hot electrons obeying nonthermal distribution, and stationary ions. For this purpose, the hydrodynamic equations for the cold magnetized electron fluid, nonthermal electron density distribution, and the Poisson equation are used to derive the corresponding nonlinear evolution equation, Zkharov-Kuznetsov (ZK) equation, in the small- but finite- amplitude regime. The ZK equation is solved analytically and it is found that it supports both solitary and blow-up solutions. It is found that rarefactive electron-acoustic solitary waves strongly depend on the density and temperature ratios of the hot-to-cold electron species as well as the nonthermal electron parameter. Furthermore, there is a critical value for the nonthermal electron parameter, which decides whether the electron-acoustic solitary wave's amplitude is decreased or increased by changing various plasma parameters. Importantly, the change of the propagation angles leads to miss the balance between the nonlinearity and dispersion; hence, the localized pulses convert to explosive/blow-up pulses. The relevance of this study to the nonlinear electron-acoustic structures in the dayside auroral zone in the light of Viking satellite observations is discussed.
Three-dimensional charge coupled device
Conder, Alan D. (Tracy, CA); Young, Bruce K. F. (Livermore, CA)
1999-01-01T23:59:59.000Z
A monolithic three dimensional charged coupled device (3D-CCD) which utilizes the entire bulk of the semiconductor for charge generation, storage, and transfer. The 3D-CCD provides a vast improvement of current CCD architectures that use only the surface of the semiconductor substrate. The 3D-CCD is capable of developing a strong E-field throughout the depth of the semiconductor by using deep (buried) parallel (bulk) electrodes in the substrate material. Using backside illumination, the 3D-CCD architecture enables a single device to image photon energies from the visible, to the ultra-violet and soft x-ray, and out to higher energy x-rays of 30 keV and beyond. The buried or bulk electrodes are electrically connected to the surface electrodes, and an E-field parallel to the surface is established with the pixel in which the bulk electrodes are located. This E-field attracts charge to the bulk electrodes independent of depth and confines it within the pixel in which it is generated. Charge diffusion is greatly reduced because the E-field is strong due to the proximity of the bulk electrodes.
A three-dimensional adaptive method based on the iterative grid redistribution
Wang, Desheng
grid equation systems and an efficient method for inverting a map by computing isoA three-dimensional adaptive method based on the iterative grid redistribution Desheng Wang on iterative grid redistribution technique introduced in [J. Comput. Phys. 159 (2000) 246]. The key step
Three-Dimensional Composite Nanostructures for Lean NOx Emission...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Emission Control Catalysts Three-Dimensional Composite Nanostructures for Lean NOx Emission Control Ultra-efficient, Robust and Well-defined Nano-Array based Monolithic Catalysts...
Three-Dimensional Thermal Tomography Advances Cancer Treatment...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Three-Dimensional Thermal Tomography Advances Cancer Treatment Technology available for licensing: A 3D technique to detect early skin changes due to radiation treatment in breast...
Three-Dimensional Composite Nanostructures for Lean NOx Emission...
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More Documents & Publications Three-Dimensional Composite Nanostructures for Lean NOx Emission Control Monolithic Metal Oxide based Composite Nanowire Lean NOx Emission Control...
Three-Dimensional Inversion of Magnetotelluric Data on a PC,...
Coso Geothermal Field Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: Three-Dimensional Inversion of Magnetotelluric Data on a PC,...
Optically Fabricated Three Dimensional Nanofluidic Mixers for Microfluidic
Rogers, John A.
Optically Fabricated Three Dimensional Nanofluidic Mixers for Microfluidic Devices Seokwoo Jeon in which large numbers (>2000) of lithographically defined 3D nanofluidic pathways (50-300 nm wide
The higher spin Laplace operator
Hendrik De Bie; David Eelbode; Matthias Roels
2015-01-24T23:59:59.000Z
This paper deals with a certain class of second-order conformally invariant operators acting on functions taking values in particular (finite-dimensional) irreducible representations of the orthogonal group. These operators can be seen as a generalisation of the Laplace operator to higher spin as well as a second order analogue of the Rarita-Schwinger operator. To construct these operators, we will use the framework of Clifford analysis, a multivariate function theory in which arbitrary irreducible representations for the orthogonal group can be realised in terms of polynomials satisfying a system of differential equations. As a consequence, the functions on which this particular class of operators act are functions taking values in the space of harmonics homogeneous of degree k. We prove the ellipticity of these operators and use this to investigate their kernel, focusing on both polynomial solutions and the fundamental solution.
Resonant Interactions in Rotating Homogeneous Three-dimensional Turbulence
Q. Chen; S. Chen; G. L. Eyink; D. D. Holm
2004-04-29T23:59:59.000Z
Direct numerical simulations of three-dimensional (3D) homogeneous turbulence under rapid rigid rotation are conducted to examine the predictions of resonant wave theory for both small Rossby number and large Reynolds number. The simulation results reveal that there is a clear inverse energy cascade to the large scales, as predicted by 2D Navier-Stokes equations for resonant interactions of slow modes. As the rotation rate increases, the vertically-averaged horizontal velocity field from 3D Navier-Stokes converges to the velocity field from 2D Navier-Stokes, as measured by the energy in their difference field. Likewise, the vertically-averaged vertical velocity from 3D Navier-Stokes converges to a solution of the 2D passive scalar equation. The energy flux directly into small wave numbers in the $k_z=0$ plane from non-resonant interactions decreases, while fast-mode energy concentrates closer to that plane. The simulations are consistent with an increasingly dominant role of resonant triads for more rapid rotation.
A pseudo three-dimensional convection model
Jenkins, Edwin Wayne
1976-01-01T23:59:59.000Z
(2) (3) hu hv Lw Wx hy dz (5) The variables u, v, and w are, respectively, the components of' motion in the x, y, z directions. The variable, p, is the ratio of' pressure to the density, b is buoyancy, and F( ) is f'ric*ion. ly defined as $2... The derivatives bu/by, hw/by, bb/by can be treated as new variables u . w , b for which new independent equations y v y are needed. For example, the equation ? (u ) = -u ? (u ) -w ? (u ) -v~ (u ) hu hu y dx y hz y hy y hy bx ) + ? (E) (7) hv hu hw hu dy dy hy...
Synthetic Spectrum Methods for Three-Dimensional Supernova Models
R. C. Thomas
2003-10-21T23:59:59.000Z
Current observations stimulate the production of fully three-dimensional explosion models, which in turn motivates three-dimensional spectrum synthesis for supernova atmospheres. We briefly discuss techniques adapted to address the latter problem, and consider some fundamentals of line formation in supernovae without recourse to spherical symmetry. Direct and detailed extensions of the technique are discussed, and future work is outlined.
Coupled models and parallel simulations for three-dimensional full-Stokes ice sheet modeling
Zhang, Huai [Graduate University of Chinese Academy of Sciences; Ju, Lili [University of South Carolina; Gunzburger, Max [Florida State University; Ringler, Todd [Los Alamos National Laboratory; Price, Stephen [Los Alamos National Laboratory
2011-01-01T23:59:59.000Z
A three-dimensional full-Stokes computational model is considered for determining the dynamics, temperature, and thickness of ice sheets. The governing thermomechanical equations consist of the three-dimensional full-Stokes system with nonlinear rheology for the momentum, an advective-diffusion energy equation for temperature evolution, and a mass conservation equation for icethickness changes. Here, we discuss the variable resolution meshes, the finite element discretizations, and the parallel algorithms employed by the model components. The solvers are integrated through a well-designed coupler for the exchange of parametric data between components. The discretization utilizes high-quality, variable-resolution centroidal Voronoi Delaunay triangulation meshing and existing parallel solvers. We demonstrate the gridding technology, discretization schemes, and the efficiency and scalability of the parallel solvers through computational experiments using both simplified geometries arising from benchmark test problems and a realistic Greenland ice sheet geometry.
New advances in three-dimensional controlled-sourceelectromagnetic inversion
Commer, Michael; Newman, Gregory A.
2007-05-19T23:59:59.000Z
New techniques for improving both the computational andimaging performance of the three dimensional (3D) electromagnetic inverseproblem are presented. A non-linear conjugate gradient algorithm is theframework of the inversion scheme. Full wave equation modelling forcontrolled sources is utilized for data simulation along with anefficient gradient computation approach for the model update. Improvingthe modelling efficiency of the 3D finite difference method involves theseparation of the potentially large modelling mesh, defining the set ofmodel parameters, from the computational finite difference meshes usedfor field simulation. Grid spacings and thus overall grid sizes can bereduced and optimized according to source frequencies and source-receiveroffsets of a given input data set. Further computational efficiency isobtained by combining different levels of parallelization. While theparallel scheme allows for an arbitrarily large number of parallel tasks,the relative amount of message passing is kept constant. Imageenhancement is achieved by model parameter transformation functions,which enforce bounded conductivity parameters and thus prevent parameterovershoots. Further, a remedy for treating distorted data within theinversion process is presented. Data distortions simulated here includepositioning errors and a highly conductive overburden, hiding the desiredtarget signal. The methods are demonstrated using both synthetic andfield data.
Title of dissertation: THREE-DIMENSIONAL DISSIPATION SCALE MEASUREMENTS OF
Lathrop, Daniel P.
ABSTRACT Title of dissertation: THREE-DIMENSIONAL DISSIPATION SCALE MEASUREMENTS OF TURBULENT FLOWS Benjamin Wolf Zeff, Doctor of Philosophy, 2002 Dissertation directed by: Professor Daniel P. Lathrop the smallest relevant spatial and temporal scales in three dimensions. This dissertation details
Validation of a Three Dimensional Particle Tracking Velocimetry Software
Goumnerov, Hristo
2014-08-01T23:59:59.000Z
In the present research, the three dimensional particle tracking software OpenPTV is validated with synthetic images from the Standard PIV project by the Visualization Society of Japan, and with experimental data from the twin-jet facility...
Three-Dimensional Lithium-Ion Battery Model (Presentation)
Kim, G. H.; Smith, K.
2008-05-01T23:59:59.000Z
Nonuniform battery physics can cause unexpected performance and life degradations in lithium-ion batteries; a three-dimensional cell performance model was developed by integrating an electrode-scale submodel using a multiscale modeling scheme.
Origami nanofabrication of three-dimensional electrochemical energy storage devices
In, Hyun Jin
2005-01-01T23:59:59.000Z
The Nanostructured (TM) 3D Fabrication and Assembly Process was developed as a novel method of creating three-dimensional (3D) nanostructured devices using two- dimensional micro- and nanopatterning tools and techniques. ...
Design and transformation of three dimensional pupils : diffractive and subwavelength
Gao, Hanhong
2014-01-01T23:59:59.000Z
Three dimensional pupils are investigated in both diffractive and subwavelength regimes and in various applications to shape the flow of light. In diffractive regime, volume holograms are good candidates for pupils of ...
Reactive binders for metal parts produced by Three Dimensional Printing
Yoo, Helen Jean
1997-01-01T23:59:59.000Z
Three Dimensional Printing (3DP) is a solid free form fabrication process which enables the construction of parts directly from computer-aided design (CAD) models. In the current process, metal parts are produced by printing ...
Copper wafer bonding in three-dimensional integration
Chen, Kuan-Neng, 1974-
2005-01-01T23:59:59.000Z
Three-dimensional (3D) integration, in which multiple layers of devices are stacked with high density of interconnects between the layers, offers solutions for problems when the critical dimensions in integrated circuits ...
Three-dimensional object registration using wavelet features
Chalfant, Julie Steele
2008-01-01T23:59:59.000Z
Recent developments in shape-based modeling and data acquisition have brought three-dimensional models to the forefront of computer graphics and visualization research. New data acquisition methods are producing large ...
Tungsten carbide-cobalt by Three Dimensional Printing
Kelley, Andrew, III
1998-01-01T23:59:59.000Z
Three Dimensional Printing is an additive manufacturing process for rapid prototyping ceramic and metallic parts [Sachs, et al, 1990]. Green (not sintered) tungsten carbide-cobalt parts must have a density greater than 50% ...
Numerical simulation of three-dimensional electrical flow through geomaterials
Akhtar, Anwar Saeed
1998-01-01T23:59:59.000Z
components in different arrangements (Mitchell 1993; Shang et al. 1995). These are very simple models and have been verified by experiments that consider only one-dimensional flow of current. In actual practice, current flow is three-dimensional around... the source. Methods do not exist to analyze three-dimensional current flow through circuit elements other than resistors. Thus, there is a need to develop methods to overcome these shortcomings. Electrical cone penetrometers have been used to convey...
Einat, Aharonov
of partial differential equations which are applicable above the Darcy scale. Our three-dimensional numerical of temperatures is much higher. Geologists, hydrologists, oil companies, companies con- cerned with environmental and Fogler, 1988], to solutions of macroscopic partial differential equations [Chadam et al., 1986; Ortoleva
Ray tracing a three dimensional scene using a grid
Wald, Ingo; Ize, Santiago; Parker, Steven G; Knoll, Aaron
2013-02-26T23:59:59.000Z
Ray tracing a three-dimensional scene using a grid. One example embodiment is a method for ray tracing a three-dimensional scene using a grid. In this example method, the three-dimensional scene is made up of objects that are spatially partitioned into a plurality of cells that make up the grid. The method includes a first act of computing a bounding frustum of a packet of rays, and a second act of traversing the grid slice by slice along a major traversal axis. Each slice traversal includes a first act of determining one or more cells in the slice that are overlapped by the frustum and a second act of testing the rays in the packet for intersection with any objects at least partially bounded by the one or more cells overlapped by the frustum.
Numerical study of three-dimensional PIC for the surface plasmon excitation based on Drude model
Liu, La-Qun; Wang, Hui-Hui; Liu, Da-Gang
2015-01-01T23:59:59.000Z
This paper explores the time-domain equations of noble metals, in which Drude model is adopted to describe the dielectric constant, to implement three-dimensional particle-in-cell (PIC) simulations for the surface plasmon excitation with the finite-difference time-domain method (FDTD). A three-dimensional model for an electron bunch movement near the metal film is constructed, and particle-in-cell (PIC) simulations are carried out with various metal films of different thicknesses. The frequency of surface plasmon obtained from PIC simulation is agreed with that from theory. Furthermore, the surface plasmon wave properties of excitation and propagation with the metal film is summarized by PIC results.
Three-dimensional boron particle loaded thermal neutron detector
Nikolic, Rebecca J.; Conway, Adam M.; Graff, Robert T.; Kuntz, Joshua D.; Reinhardt, Catherine; Voss, Lars F.; Cheung, Chin Li; Heineck, Daniel
2014-09-09T23:59:59.000Z
Three-dimensional boron particle loaded thermal neutron detectors utilize neutron sensitive conversion materials in the form of nano-powders and micro-sized particles, as opposed to thin films, suspensions, paraffin, etc. More specifically, methods to infiltrate, intersperse and embed the neutron nano-powders to form two-dimensional and/or three-dimensional charge sensitive platforms are specified. The use of nano-powders enables conformal contact with the entire charge-collecting structure regardless of its shape or configuration.
Bootstrapping the Three-Dimensional Supersymmetric Ising Model
Bobev, Nikolay; Mazac, Dalimil; Paulos, Miguel F
2015-01-01T23:59:59.000Z
We implement the conformal bootstrap program for three-dimensional CFTs with $\\mathcal{N}=2$ supersymmetry and find universal constraints on the spectrum of operator dimensions in these theories. By studying the bounds on the dimension of the first scalar appearing in the OPE of a chiral and an anti-chiral primary, we find a kink at the expected location of the critical three-dimensional $\\mathcal{N}=2$ Wess-Zumino model, which can be thought of as a supersymmetric analog of the critical Ising model. Focusing on this kink, we determine, to high accuracy, the low-lying spectrum of operator dimensions of the theory.
Infrared regular representation of the three dimensional massless Nelson model
Infrared regular representation of the three dimensional massless Nelson model J#19;ozsef L this Gaussian measure space. KEYWORDS: Nelson's scalar #12;eld model, infrared regular representation, ground] of a spinless electron coupled to a scalar massless Bose #12;eld is infrared divergent in 3 space dimensions
Automation of Three-Dimensional Cell Culture in Arrayed Microfluidic
Beebe, David J.
. A Peltier cooler maintains the collagen as a liquid at 4 C during cell seeding, followed by polymerizationAutomation of Three-Dimensional Cell Culture in Arrayed Microfluidic Devices Sara I. Montanez of Wisconsin-Madison, Madison, WI The increasing interest in studying the interactions between cells
Structure Preserving Optimal Control of Three-Dimensional Compass Gait
Leyendecker, Sigrid
Structure Preserving Optimal Control of Three-Dimensional Compass Gait Sigrid Leyendecker, David con- siders the optimal control of a bipedal compass gait by modeling the double stance configuration compass biped model. This control task has been previously addressed with various biped models
Are three-dimensional spider webs defensive adaptations?
Blackledge, Todd
LETTER Are three-dimensional spider webs defensive adaptations? Todd A. Blackledge1 *, Jonathan A-mail: tab42@cornell.edu Abstract Spider webs result from complex behaviours that have evolved under many selective pressures. Webs have been primarily considered to be foraging adaptations, neglecting
THREE DIMENSIONAL VISUALIZATIONS FOR POWER SYSTEM CONTINGENCY ANALYSIS VOLTAGE DATA
that the power systems are now often operated closer to their limits to maximum transmission system utilizationTHREE DIMENSIONAL VISUALIZATIONS FOR POWER SYSTEM CONTINGENCY ANALYSIS VOLTAGE DATA Y. Sun IEEE security assessment is critical for detecting underlying problems in a power system. More frequent CA
A new acoustic three dimensional intensity and energy density probe
Boyer, Edmond
A new acoustic three dimensional intensity and energy density probe F. Aymea , C. Carioub , M is a great advantage. In this frame, a new intensity acoustic probe has been developed to compute acoustic quantities which can be input data for energetic identification methods. 1 Introduction Noise matters
Preconditioned Conjugate Gradient Methods for Three Dimensional Linear Elasticity
Waterloo, University of
Preconditioned Conjugate Gradient Methods for Three Dimensional Linear Elasticity by John Kenneth. A brief review is also made of stopping criteria for conjugate gradient solvers. One method based and tested with poor results. iv #12;Contents 1 Introduction 1 1.1 Preconditioned Conjugate Gradient Methods
The Coverage Problem in Three-Dimensional Wireless Sensor Networks
Tseng, Yu-Chee
The Coverage Problem in Three-Dimensional Wireless Sensor Networks Chi-Fu Huang, Yu-Chee Tseng- bedded micro-sensing MEMS technologies has made wireless sensor networks possible. Such environments may protocols [7], [8], [9]. Localization and positioning applications of wireless sensor networks are discussed
Three dimensional visualization and comparison of impressions on fired bullets
Tokyo, University of
obtain fine 3D maps of striation surfaces. The shape of striation surface is expected to be printed utilize three dimensional (3D) geometric data of tool marks that are free from lighting condition. In this study, we focused on 3D geometric data of landmark impressions on fired bullets for identification. We
Three-Dimensional Routing in Underwater Acoustic Sensor Networks
Pompili, Dario
Three-Dimensional Routing in Underwater Acoustic Sensor Networks Dario Pompili and Tommaso Melodia applications in oceanographic data collection, pollution monitoring, offshore exploration, disaster prevention in a 3D underwa- ter acoustic sensor network is investigated at the network layer, by considering
Three-dimensional stability of Burgers vortices Thierry Gallay
Gallay, Thierry
Three-dimensional stability of Burgers vortices Thierry Gallay Institut Fourier UniversitÂ´e de Grenoble I BP 74 38402 Saint-Martin-d'H`eres, France Thierry.Gallay@ujf-grenoble.fr Yasunori Maekawa and then in the general case by Gallay and Wayne [9], see also [2, 12, 13]. Moreover, a lot is known about the spectrum
Three-dimensional stability of Burgers vortices Thierry Gallay
Three-dimensional stability of Burgers vortices Thierry Gallay Institut Fourier UniversitÂ´e de Grenoble I BP 74 38402 Saint-Martin-d'H`eres, France Thierry.Gallay@ujf-grenoble.fr Yasunori Maekawa and then by Gallay and Wayne [11] in the general case. Moreover, a lot is known about the spectrum of the linearized
Three-Dimensional and Multilayer Nanostructures Formed by Nanotransfer
Rogers, John A.
ABSTRACT This letter describes the use of nanotransfer printing (nTP) for forming three-dimensional (3D to as nanotransfer printing (nTP),8-11 can be used to build a range of complex 3D structures with feature sizes patterning. Furthermore, the purely additive nature of nTP allows these 2D and 3D printing steps
Energy Distribution of Nanoflares in Three-Dimensional Simulations of
Ng, Chung-Sang
Energy Distribution of Nanoflares in Three-Dimensional Simulations of Coronal Heating Chung-Sang Ng-dimensional direct simulations due to obvious numerical difficulties. We will present energy distributions and other;3D Simulation of Parker's model · Magnetic energy limited by disruptions. ==0.000625(64x64x16) =0
Energy Distribution of Nanoflares in Three-Dimensional Simulations of
Ng, Chung-Sang
Energy Distribution of Nanoflares in Three-Dimensional Simulations of Coronal Heating Chung-Sang Ng difficulties. We will present energy distributions and other statistics based on our simulations, calculated simulation results. · Parker's nanoflare heating model vs observations · Energy distributions of nanoflares
Strategies for three-dimensional particle tracking with holographic video
Grier, David
Strategies for three-dimensional particle tracking with holographic video microscopy Fook Chiong Research, New York University, New York, NY 10003 Abstract: The video stream captured by an in References and links 1. J. C. Crocker and D. G. Grier, "Methods of digital video microscopy for colloidal
Field Optimization of Three Dimensional High Voltage C. Trinitis
Stamatakis, Alexandros
Field Optimization of Three Dimensional High Voltage Equipment C. Trinitis Lehrstuhl f The goal of finding an optimal electric field strength distribution for arbitrary three diÂ mensionalÂ cal optimization algorithm. The package obÂ tained from these three components is then able
Fabrication Technologies for Three-Dimensional Integrated Circuits Rafael Reif
He, Lei
Fabrication Technologies for Three-Dimensional Integrated Circuits Rafael Reif Dept. of Electrical Engineering and Computer Science, MIT Cambridge, MA reif@mit.edu Andy Fan Dept. of Electrical Engineering, MIT Cambridge, MA knchen@mit.edu Shamik Das Dept. of Electrical Engineering and Computer Science, MIT
Three Dimensional Dielectrophoretic Assembly of Nanostructures on a Micromachined Platform
Dokmeci, Mehmet
Three Dimensional Dielectrophoretic Assembly of Nanostructures on a Micromachined Platform University, Boston, MA-02115, USA ABSTRACT In this paper, we introduce a novel platform for selectively. The microfabricated platform based nanoscale assembly is quite versatile and has potential applications in fabricating
Improved data representation for three-dimensional analysis
Olah, Desiree Jeanine
1992-01-01T23:59:59.000Z
. OB JECTIVES The purpose of this research was to evaluate the capabilities of spatially-oriented software to improve data representation for three-dimensional analysis. The specific objectives were to: I) Select appropriate spatial analysis... to perform their study. Manley and Tallet (1990) found that the 1VM gave them the capability to calculate volumes between complex surfaces within user defined regions and to provide them with information about specific features or water masses that are far...
THREE-DIMENSIONAL DISCRETE ORDINATES REACTOR ASSEMBLY CALCULATIONS ON GPUS
Evans, Thomas M [ORNL; Joubert, Wayne [ORNL; Hamilton, Steven P [ORNL; Johnson, Seth R [ORNL; Turner, John A [ORNL; Davidson, Gregory G [ORNL; Pandya, Tara M [ORNL
2015-01-01T23:59:59.000Z
In this paper we describe and demonstrate a discrete ordinates sweep algorithm on GPUs. This sweep algorithm is nested within a multilevel comunication-based decomposition based on energy. We demonstrated the effectiveness of this algorithm on detailed three-dimensional critical experiments and PWR lattice problems. For these problems we show improvement factors of 4 6 over conventional communication-based, CPU-only sweeps. These sweep kernel speedups resulted in a factor of 2 total time-to-solution improvement.
Three-dimensional virtual environment for spatial development
Bateman, Kathleen Suzanne
2005-02-17T23:59:59.000Z
virtual three-dimensional scene and move through it, I developed a computer program called Viewpoints. The program's graphical interface presents a 3D perspective view of an environment. Simple geometric objects such as boxes and spheres can be placed... manipulations. Functions with similar purposes act and look similar. When appropriate, menu options matched in word choice and purpose to standard menu options available in other computer programs. Consistent use of color plays an important role in revealing...
Particle acceleration in three-dimensional tearing configurations
Christoph Nodes; Guido T. Birk; Harald Lesch; R. Schopper
2003-01-17T23:59:59.000Z
In three-dimensional electromagnetic configurations that result from unstable resistive tearing modes particles can efficiently be accelerated to relativistic energies. To prove this resistive magnetohydrodynamic simulations are used as input configurations for successive test particle simulations. The simulations show the capability of three-dimensional non-linearly evolved tearing modes to accelerate particles perpendicular to the plane of the reconnecting magnetic field components. The simulations differ considerably from analytical approaches by involving a realistic three-dimensional electric field with a non-homogenous component parallel to the current direction. The resulting particle spectra exhibit strong pitch-angle anisotropies. Typically, about 5-8 % of an initially Maxwellian distribution is accelerated to the maximum energy levels given by the macroscopic generalized electric potential structure. Results are shown for both, non-relativistic particle acceleration that is of interest, e.g., in the context of auroral arcs and solar flares, and relativistic particle energization that is relevant, e.g., in the context of active galactic nuclei.
Tracker: A three-dimensional raytracing program for ionospheric radio propagation
Argo, P.E.; DeLapp, D.; Sutherland, C.D.; Farrer, R.G.
1994-12-01T23:59:59.000Z
TRACKER is an extension of a three-dimensional Hamiltonian raytrace code developed some thirty years ago by R. Michael Jones. Subsequent modifications to this code, which is commonly called the {open_quotes}Jones Code,{close_quotes} were documented by Jones and Stephensen (1975). TRACKER incorporates an interactive user`s interface, modern differential equation integrators, graphical outputs, homing algorithms, and the Ionospheric Conductivity and Electron Density (ICED) ionosphere. TRACKER predicts the three-dimensional paths of radio waves through model ionospheres by numerically integrating Hamilton`s equations, which are a differential expression of Fermat`s principle of least time. By using continuous models, the Hamiltonian method avoids false caustics and discontinuous raypath properties often encountered in other raytracing methods. In addition to computing the raypath, TRACKER also calculates the group path (or pulse travel time), the phase path, the geometrical (or {open_quotes}real{close_quotes}) pathlength, and the Doppler shift (if the time variation of the ionosphere is explicitly included). Computational speed can be traded for accuracy by specifying the maximum allowable integration error per step in the integration. Only geometrical optics are included in the main raytrace code; no partial reflections or diffraction effects are taken into account. In addition, TRACKER does not lend itself to statistical descriptions of propagation -- it requires a deterministic model of the ionosphere.
Methods for preparation of three-dimensional bodies
Mulligan, Anthony C. (Tucson, AZ); Rigali, Mark J. (Carlsbad, NM); Sutaria, Manish P. (Malden, MA); Artz, Gregory J. (Tucson, AZ); Gafner, Felix H. (Tucson, AZ); Vaidyanathan, K. Ranji (Tucson, AZ)
2008-06-17T23:59:59.000Z
Processes for mechanically fabricating two and three-dimensional fibrous monolith composites include preparing a fibrous monolith filament from a core composition of a first powder material and a boundary material of a second powder material. The filament includes a first portion of the core composition surrounded by a second portion of the boundary composition. One or more filaments are extruded through a mechanically-controlled deposition nozzle onto a working surface to create a fibrous monolith composite object. The objects may be formed directly from computer models and have complex geometries.
Three-Dimensional Hairy Black Holes in Teleparallel Gravity
P. A. González; Joel Saavedra; Yerko Vásquez
2015-02-11T23:59:59.000Z
We consider three-dimensional gravity based on torsion. Specifically, we consider an extension of the so-called Teleparallel Equivalent of General Relativity in the presence of a scalar field with a self-interacting potential, where the scalar field is non-minimally coupled with the torsion scalar. Then, we find asymptotically AdS hairy black hole solutions, which are characterized by a scalar field with a power-law behavior, being regular outside the event horizon and null at spatial infinity and by a self-interacting potential, which tends to an effective cosmological constant at spatial infinity.
Three dimensional amorphous silicon/microcrystalline silicon solar cells
Kaschmitter, J.L.
1996-07-23T23:59:59.000Z
Three dimensional deep contact amorphous silicon/microcrystalline silicon (a-Si/{micro}c-Si) solar cells are disclosed which use deep (high aspect ratio) p and n contacts to create high electric fields within the carrier collection volume material of the cell. The deep contacts are fabricated using repetitive pulsed laser doping so as to create the high aspect p and n contacts. By the provision of the deep contacts which penetrate the electric field deep into the material where the high strength of the field can collect many of the carriers, thereby resulting in a high efficiency solar cell. 4 figs.
Ghost imaging for three-dimensional optical security
Chen, Wen, E-mail: elechenw@nus.edu.sg; Chen, Xudong [Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583 (Singapore)] [Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583 (Singapore)
2013-11-25T23:59:59.000Z
Ghost imaging has become increasingly popular in quantum and optical application fields. Here, we report three-dimensional (3D) optical security using ghost imaging. The series of random phase-only masks are sparsified, which are further converted into particle-like distributions placed in 3D space. We show that either an optical or digital approach can be employed for the encoding. The results illustrate that a larger key space can be generated due to the application of 3D space compared with previous works.
Three-dimensional simulations of type Ia supernovae
M. Reinecke; W. Hillebrandt; J. C. Niemeyer
2002-06-26T23:59:59.000Z
We present the results of three-dimensional hydrodynamical simulations of the subsonic thermonuclear burning phase in type Ia supernovae. The burning front model contains no adjustable parameters so that variations of the explosion outcome can be linked directly to changes in the initial conditions. In particular, we investigate the influence of the initial flame geometry on the explosion energy and find that it appears to be weaker than in 2D. Most importantly, our models predict global properties such as the produced nickel masses and ejecta velocities within their observed ranges without any fine tuning.
Three-dimensional simulations of type Ia supernovae
Reinecke, M; Niemeyer, J C
2002-01-01T23:59:59.000Z
We present the results of three-dimensional hydrodynamical simulations of the subsonic thermonuclear burning phase in type Ia supernovae. The burning front model contains no adjustable parameters so that variations of the explosion outcome can be linked directly to changes in the initial conditions. In particular, we investigate the influence of the initial flame geometry on the explosion energy and find that it appears to be weaker than in 2D. Most importantly, our models predict global properties such as the produced nickel masses and ejecta velocities within their observed ranges without any fine tuning.
Three-dimensional asymptotically flat Einstein-Maxwell theory
Glenn Barnich; Pierre-Henry Lambert; Pujian Mao
2015-03-03T23:59:59.000Z
Three-dimensional Einstein-Maxwell theory with non trivial asymptotics at null infinity is solved. The symmetry algebra is a Virasoro-Kac-Moody type algebra that extends the bms3 algebra of the purely gravitational case. Solution space involves logarithms and provides a tractable example of a polyhomogeneous solution space. The associated surface charges are non-integrable and non-conserved due to the presence of electromagnetic news. As in the four dimensional purely gravitational case, their algebra involves a field-dependent central charge.
Three-dimensional "Mercedes-Benz" model for water
Cristiano L. Dias; Tapio Ala-Nissila; Martin Grant; Mikko Karttunen
2009-02-13T23:59:59.000Z
In this paper we introduce a three-dimensional version of the Mercedes-Benz model to describe water molecules. In this model van der Waals interactions and hydrogen bonds are given explicitly through a Lennard-Jones potential and a Gaussian orientation-dependent terms, respectively. At low temperature the model freezes forming Ice-I and it reproduces the main peaks of the experimental radial distribution function of water. In addition to these structural properties, the model also captures the thermodynamical anomalies of water: the anomalous density profile, the negative thermal expansivity, the large heat capacity and the minimum in the isothermal compressibility.
Three dimensional amorphous silicon/microcrystalline silicon solar cells
Kaschmitter, James L. (Pleasanton, CA)
1996-01-01T23:59:59.000Z
Three dimensional deep contact amorphous silicon/microcrystalline silicon (a-Si/.mu.c-Si) solar cells which use deep (high aspect ratio) p and n contacts to create high electric fields within the carrier collection volume material of the cell. The deep contacts are fabricated using repetitive pulsed laser doping so as to create the high aspect p and n contacts. By the provision of the deep contacts which penetrate the electric field deep into the material where the high strength of the field can collect many of the carriers, thereby resulting in a high efficiency solar cell.
Discrete canonical analysis of three dimensional gravity with cosmological constant
J. Berra-Montiel; J. E. Rosales-Quintero
2014-06-03T23:59:59.000Z
We discuss the interplay between standard canonical analysis and canonical discretization in three-dimensional gravity with cosmological constant. By using the Hamiltonian analysis, we find that the continuum local symmetries of the theory are given by the on-shell space-time diffeomorphisms, which at the action level, corresponds to the Kalb-Ramond transformations. At the time of discretization, although this symmetry is explicitly broken, we prove that the theory still preserves certain gauge freedom generated by a constant curvature relation in terms of holonomies and the Gauss's law in the lattice approach.
analytical three-dimensional solutions: Topics by E-print Network
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are two- or three-dimensional. Since the deviation from a one-dimensional solution is small, we call these slightly two-dimensional and slightly three-dimensional self-similar...
Evaluation of Economic Impact of Three-Dimensional Modeling in Precast Concrete Engineering
Sacks, Rafael
Evaluation of Economic Impact of Three-Dimensional Modeling in Precast Concrete Engineering Rafael (IT); Concrete, precast; Economic factors; Three-dimensional models. Introduction "The application to this; but the funda- mental reason undoubtedly was economic." (Mitchell 1977). Intuitive assessments
NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration
Bentz, Dale P.
NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration and Microstructure Development Modeling Package. Version 3.0 Dale P. Bentz #12;NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration
Isotropic three-dimensional MRI-Fricke-infused gel dosimetry
Cho, Nai-Yu; Chu, Woei-Chyn [Institute of Biomedical Engineering, National Yang-Ming University, Taipei 11221, Taiwan (China); Huang, Sung-Cheng [Department of Molecular and Medical Pharmacology, UCLA David Geffen School of Medicine, Los Angeles, California 90095 (United States); Chung, Wen-Yuh [Neurological Institute, Taipei Veterans General Hospital, Taipei 11217, Taiwan (China); Guo, Wan-Yuo [Department of Radiology, Taipei Veterans General Hospital, Taipei 11217, Taiwan (China)
2013-05-15T23:59:59.000Z
Purpose: Fricke-infused gel has been shown to be a simple and attainable method for the conformal measurement of absorbed radiation dose. Nevertheless, its accuracy is seriously hindered by the irreversible ferric ion diffusion during magnetic resonance imaging, particularly when three-dimensional (3D) dose measurement in radiosurgery is considered. In this study, the authors developed a fast three-dimensional spin-echo based Fricke gel dosimetry technique to reduce the adverse effects of ferric ion diffusion and to obtain an accurate isotropic 3D dose measurement. Methods: A skull shaped phantom containing Fricke-infused gel was irradiated using Leksell Gamma Knife. The rapid image-based dosimetry technique was applied with the use of a 3D fast spin-echo magnetic resonance imaging sequence. The authors mathematically derived and experimentally validated the correlations between dose-response characteristics and parameters of the 3D fast spin-echo MR imaging sequence. Absorbed dose profiles were assessed and compared to the calculated profiles given by the Gamma Knife treatment planning system. Coefficient of variance (CV%) and coefficient of determination (R{sup 2}) were used to evaluate the precision of dose-response curve estimation. The agreement between the measured and the planned 3D dose distributions was quantified by gamma-index analysis of two acceptance criteria. Results: Proper magnetic resonance imaging parameters were explored to render an accurate three-dimensional absorbed dose mapping with a 1 mm{sup 3} isotropic image resolution. The efficacy of the dose-response estimation was approved by an R{sup 2} > 0.99 and an average CV% of 1.6%. Average gamma pass-rate between the experimentally measured and GammaPlan calculated dose distributions were 83.8% and 99.7% for 2%/2 and 3%/3 mm criteria, respectively. Conclusions: With the designed MR imaging sequence and parameters, total 3D MR acquisition time was confined to within 20 min postirradiation, during which time ferric ion diffusion effects were negligible, thus enabling an accurate 3D radiation dose measurement.
Application of three-dimensional solar radiative transfer to mountains Y. Chen,1,2
Liou, K. N.
Application of three-dimensional solar radiative transfer to mountains Y. Chen,1,2 A. Hall,1 and K November 2006. [1] We developed a three-dimensional radiative transfer model simulating solar fluxes over (2006), Application of three-dimensional solar radiative transfer to mountains, J. Geophys. Res., 111, D
Dynamics of Three-Dimensional Vesicles in DC Electric fields
Ebrahim M. Kolahdouz; David Salac
2015-03-02T23:59:59.000Z
A numerical and systematic parameter study of three-dimensional vesicle electrohydrodynamics is presented to investigate the effects of different fluid and membrane properties. The dynamics of vesicles in the presence of DC electric fields is considered, both in the presence and absence of linear shear flow. For suspended vesicles it is shown that the conductivity ratio and viscosity ratio between the interior and exterior fluids, as well as the vesicle membrane capacitance, substantially affect the minimum electric field strength required to induce a full Prolate-Oblate-Prolate transition.In addition, there exists a critical electric field strength above which a vesicle will no longer tumble when exposed to linear shear flow.
Higher Derivative Terms in Three Dimensional Supersymmetric Theories
Adel Awad; Mir Faizal
2015-03-30T23:59:59.000Z
In this work, we systematically analyze higher derivative terms in the effective actions for three dimensional scalar field theories with $\\mathcal{N} =1$ supersymmetry. In these effective actions, we show that the auxiliary fields do not acquire kinetic terms and their effective actions can be expressed in terms of physical fields. We use the derivative expansion to generate four, five and six dimensional terms for $\\phi^6$ scalar field theory with $\\mathcal{N} =1$ supersymmetry. We show that along with pure fermionic terms, there are various five and six dimensional topological terms that contain bosonic and fermionic fields. Finally, we use these results to obtain higher derivative topological terms in the effective action for two M2-branes. Thus, using an off-shell formalism, we obtain several higher derivative topological terms, which we compare with an earlier study that was done using an on-shell formalism.
Higher Derivative Terms in Three Dimensional Supersymmetric Theories
Awad, Adel
2015-01-01T23:59:59.000Z
In this work, we systematically analyze higher derivative terms in the effective actions for three dimensional scalar field theories with $\\mathcal{N} =1$ supersymmetry. In these effective actions, we show that the auxiliary fields do not acquire kinetic terms and their effective actions can be expressed in terms of physical fields. We use the derivative expansion to generate four, five and six dimensional terms for $\\phi^6$ scalar field theory with $\\mathcal{N} =1$ supersymmetry. We show that along with pure fermionic terms, there are various five and six dimensional topological terms that contain bosonic and fermionic fields. Finally, we use these results to obtain higher derivative topological terms in the effective action for two M2-branes. Thus, using an off-shell formalism, we obtain several higher derivative topological terms, which we compare with an earlier study that was done using an on-shell formalism.
Three dimensional imaging detector employing wavelength-shifting optical fibers
Worstell, William A. (Framingham, MA)
1997-01-01T23:59:59.000Z
A novel detector element structure and method for its use is provided. In a preferred embodiment, one or more inorganic scintillating crystals are coupled through wavelength shifting optical fibers (WLSFs) to position sensitive photomultipliers (PS-PMTs). The superior detector configuration in accordance with this invention is designed for an array of applications in high spatial resolution gamma ray sensing with particular application to SPECT, PET and PVI imaging systems. The design provides better position resolution than prior art devices at a lower total cost. By employing wavelength shifting fibers (WLSFs), the sensor configuration of this invention can operate with a significant reduction in the number of photomultipliers and electronics channels, while potentially improving the resolution of the system by allowing three dimensional reconstruction of energy deposition positions.
Three dimensional imaging detector employing wavelength-shifting optical fibers
Worstell, W.A.
1997-02-04T23:59:59.000Z
A novel detector element structure and method for its use is provided. In a preferred embodiment, one or more inorganic scintillating crystals are coupled through wavelength shifting optical fibers (WLSFs) to position sensitive photomultipliers (PS-PMTs). The superior detector configuration in accordance with this invention is designed for an array of applications in high spatial resolution gamma ray sensing with particular application to SPECT, PET and PVI imaging systems. The design provides better position resolution than prior art devices at a lower total cost. By employing wavelength shifting fibers (WLSFs), the sensor configuration of this invention can operate with a significant reduction in the number of photomultipliers and electronics channels, while potentially improving the resolution of the system by allowing three dimensional reconstruction of energy deposition positions. 11 figs.
Accurate complex scaling of three dimensional numerical potentials
Cerioni, Alessandro [European Synchrotron Radiation Facility, 6 rue Horowitz, BP220 38043 Grenoble Cedex 9 (France); Genovese, Luigi; Duchemin, Ivan; Deutsch, Thierry [Laboratoire de simulation atomistique (L-Sim), SP2M, UMR-E CEA/UJF-Grenoble 1, INAC, Grenoble F-38054 (France)
2013-05-28T23:59:59.000Z
The complex scaling method, which consists in continuing spatial coordinates into the complex plane, is a well-established method that allows to compute resonant eigenfunctions of the time-independent Schroedinger operator. Whenever it is desirable to apply the complex scaling to investigate resonances in physical systems defined on numerical discrete grids, the most direct approach relies on the application of a similarity transformation to the original, unscaled Hamiltonian. We show that such an approach can be conveniently implemented in the Daubechies wavelet basis set, featuring a very promising level of generality, high accuracy, and no need for artificial convergence parameters. Complex scaling of three dimensional numerical potentials can be efficiently and accurately performed. By carrying out an illustrative resonant state computation in the case of a one-dimensional model potential, we then show that our wavelet-based approach may disclose new exciting opportunities in the field of computational non-Hermitian quantum mechanics.
3DD - Three Dimensional Disposal of Spent Nuclear Fuel - 12449
Dvorakova, Marketa; Slovak, Jiri [Radioactive Waste Repository Authority (RAWRA), Prague (Czech Republic)
2012-07-01T23:59:59.000Z
Three dimensional disposal is being considered as a way in which to store long-term spent nuclear fuel in underground disposal facilities in the Czech Republic. This method involves a combination of the two most common internationally recognised disposal methods in order to practically apply the advantages of both whilst, at the same time, eliminating their weaknesses; the method also allows easy removal in case of potential re-use. The proposed method for the disposal of spent nuclear fuel will reduce the areal requirements of future deep geological repositories by more than 30%. It will also simplify the container handling process by using gravitational forces in order to meet requirements concerning the controllability of processes and ensuring operational and nuclear safety. With regard to the issue of the efficient potential removal of waste containers, this project offers an ingenious solution which does not disrupt the overall stability of the original disposal complex. (authors)
Structures with three dimensional nanofences comprising single crystal segments
Goyal, Amit; Wee, Sung-Hun
2013-08-27T23:59:59.000Z
An article includes a substrate having a surface and a nanofence supported by the surface. The nanofence includes a multiplicity of primary nanorods and branch nanorods, each of the primary nanorods being attached to said substrate, and each of the branch nanorods being attached to a primary nanorods and/or another branch nanorod. The primary and branch nanorods are arranged in a three-dimensional, interconnected, interpenetrating, grid-like network defining interstices within the nanofence. The article further includes an enveloping layer supported by the nanofence, disposed in the interstices, and forming a coating on the primary and branch nanorods. The enveloping layer has a different composition from that of the nanofence and includes a radial p-n single junction solar cell photovoltaic material and/or a radial p-n multiple junction solar cell photovoltaic material.
Plasma-Ion Processing of Three-Dimensional Components
Yukimura, Ken [Department of Electrical Engineering, Doshisha University, Kyotanabe 610-0321 (Japan); Wei Ronghua [Surface Engineering Section, Materials Engineering Department, Southwest Research Institute, San Antonio, Texas 78238-5166 (United States)
2004-12-01T23:59:59.000Z
Plasma-based ion implantation and deposition (PBII and D) technology has been developed rapidly in the past decade. This technique is especially promising for modifying three-dimensional components. In PBII and D, plasma is generated in the entire processing chamber and then surrounds the components. When a train of negative voltage pulses are applied to the parts, ions are drawn to all the surfaces exposed to the plasma. At a high energy, ions are implanted to the surfaces, but at a low energy and with a proper precursor gases, ions are deposited to form a film. This technology has found applications in many areas including semiconductors, automotive, aerospace, energy and biomedical. This article reviews PBII and D fundamentals, describes features of various PBII and D systems and plasma sources, and discusses implantation and deposition techniques. The paper will also present application examples of this technology.
Axionic superconductivity in three dimensional doped narrow gap semiconductors
Pallab Goswami; Bitan Roy
2014-08-07T23:59:59.000Z
We consider the competition between the conventional s-wave and the triplet Balian-Werthamer or the B-phase pairings in the doped three dimensional narrow gap semiconductors, such as $\\mathrm{Cu}_x\\mathrm{Bi}_2\\mathrm{Se}_3$ and $\\mathrm{Sn}_{1-x}\\mathrm{In}_x\\mathrm{Te}$. When the coupling constants of the two contending channels are comparable, we find a simultaneously time-reversal and parity violating $p + is$ state at low temperatures, which provides an example of dynamic axionic state of matter. In contradistinction to the time-reversal invariant, topological B-phase, the $p + is$ state possesses gapped Majorana fermions as the surface Andreev bound states, which give rise to an anomalous surface thermal Hall effect. The anomalous gravitational and electrodynamic responses of the $p+is$ state can be described by the $\\theta$ vacuum structure, where $\\theta \
NMR Experiments on a Three-Dimensional Vibrofluidized Granular Medium
Chao Huan; Xiaoyu Yang; D. Candela; R. W. Mair; R. L. Walsworth
2003-05-12T23:59:59.000Z
A three-dimensional granular system fluidized by vertical container vibrations was studied using pulsed field gradient (PFG) NMR coupled with one-dimensional magnetic resonance imaging (MRI). The system consisted of mustard seeds vibrated vertically at 50 Hz, and the number of layers N_ell <= 4 was sufficiently low to achieve a nearly time-independent granular fluid. Using NMR, the vertical profiles of density and granular temperature were directly measured, along with the distributions of vertical and horizontal grain velocities. The velocity distributions showed modest deviations from Maxwell-Boltzmann statistics, except for the vertical velocity distribution near the sample bottom which was highly skewed and non-Gaussian. Data taken for three values of N_ell and two dimensionless accelerations Gamma=15,18 were fit to a hydrodynamic theory, which successfully models the density and temperature profiles including a temperature inversion near the free upper surface.
Three dimensional simulation for bayou choctaw strategic petroleum reserve (SPR).
Ehgartner, Brian L. (Sandia National Laboratories, Albuquerque, NM); Park, Byoung Yoon; Lee, Moo Yul
2006-12-01T23:59:59.000Z
Three dimensional finite element analyses were performed to evaluate the structural integrity of the caverns located at the Bayou Choctaw (BC) site which is considered a candidate for expansion. Fifteen active and nine abandoned caverns exist at BC, with a total cavern volume of some 164 MMB. A 3D model allowing control of each cavern individually was constructed because the location and depth of caverns and the date of excavation are irregular. The total cavern volume has practical interest, as this void space affects total creep closure in the BC salt mass. Operations including both cavern workover, where wellhead pressures are temporarily reduced to atmospheric, and cavern enlargement due to leaching during oil drawdowns that use water to displace the oil from the caverns, were modeled to account for as many as the five future oil drawdowns in the six SPR caverns. The impacts on cavern stability, underground creep closure, surface subsidence, infrastructure, and well integrity were quantified.
A three-dimensional fast solver for arbitrary vorton distributions
Strickland, J.H.; Baty, R.S.
1994-05-01T23:59:59.000Z
A method which is capable of an efficient calculation of the three-dimensional flow field produced by a large system of vortons (discretized regions of vorticity) is presented in this report. The system of vortons can, in turn, be used to model body surfaces, container boundaries, free-surfaces, plumes, jets, and wakes in unsteady three-dimensional flow fields. This method takes advantage of multipole and local series expansions which enables one to make calculations for interactions between groups of vortons which are in well-separated spatial domains rather than having to consider interactions between every pair of vortons. In this work, series expansions for the vector potential of the vorton system are obtained. From such expansions, the three components of velocity can be obtained explicitly. A Fortran computer code FAST3D has been written to calculate the vector potential and the velocity components at selected points in the flow field. In this code, the evaluation points do not have to coincide with the location of the vortons themselves. Test cases have been run to benchmark the truncation errors and CPU time savings associated with the method. Non-dimensional truncation errors for the magnitudes of the vector potential and velocity fields are on the order of 10{sup {minus}4}and 10{sup {minus}3} respectively. Single precision accuracy produces errors in these quantities of up to 10{sup {minus}5}. For less than 1,000 to 2,000 vortons in the field, there is virtually no CPU time savings with the fast solver. For 100,000 vortons in the flow, the fast solver obtains solutions in 1 % to 10% of the time required for the direct solution technique depending upon the configuration.
Three-dimensional theory of Smith-Purcell free-electron laser with dielectric loaded grating
Cao, Miaomiao, E-mail: mona486@yeah.net; Li, Ke, E-mail: like3714@163.com [Key Laboratory of High Power Microwave Sources and Technologies, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, School of Electronic Science and Technology, Beijing 100049 (China); Liu, Wenxin, E-mail: lwenxin@mail.ie.ac.cn; Wang, Yong, E-mail: wangyong3845@sina.com [Key Laboratory of High Power Microwave Sources and Technologies, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190 (China)
2014-09-14T23:59:59.000Z
A dielectric loaded rectangular grating for Smith-Purcell devices is proposed in this paper. Regarding the electron beam as a moving plasma dielectric, a three dimensional (3D) linear theory of beam-wave interaction is developed. The first and second order growth rates are calculated, which are obtained by expanding hot dispersion equation at synchronous point. The results show that the cutoff frequency is affected by grating width. The dispersion curve becomes flatter and shifts towards lower frequency by loading dielectric in grooves. The simulation results, which are obtained by a 3D particle-in-cell code, are in good agreement with theoretical calculations. Compared the first and second order growth rate, it shows that the discrepancy is large when beam parameters are selected with high values. In this case, it is necessary to apply the second order growth rate, which can accurately describe the process of beam-wave interaction.
Le, T.L.
1992-03-01T23:59:59.000Z
TRIMHX is a fundamental Reactor Analysis tool in use at the Savannah River Site (SRS) and is an integral part of the Generalized Reactor Analysis Subsystem (GRASS). TRIMHX solves the time dependent multigroup neutron diffusion equation in two and three dimensional hexagonal geometry by standard and coarse mesh finite difference methods. The TRIMHX implementation assumes the solution to this equation can be discretized in space, energy, and time. These are industry accepted approaches which can be found in many nuclear engineering books. This report concerns the verification and validation of TRIMHX, a transient two and three dimensional hex-z diffusion theory code. The validation was performed to determine the accuracy of the code, and the verification was performed to determine if the code was correctly using the correct theory and that all the subroutines function as required. For TRIMHX, the validation requirement was satisfied by comparing the results of the code with experiments and benchmarking the code against other standard or validated code results. The verification requirement for TRIMHX was performed indirectly since it is impossible and not necessary to reverify a large code like TRIMHX line by line. The extensive operations history of TRIMHX in conjunction with the comparisons against many numerical experiments (exact solutions) and other diffusion theory codes is sufficient to establish that the code is functioning as intended and therefore it is verified. This report summarizes four sets of experiments performed in 1974, 1977, and 1988, two DIF3D/TRIMHX comparison problems performed in 1991, a DIF3D/FX2-TH/TRIMHX comparison problem produced for this report, and the comparison of TRIMHX/GRIMHX initial static calculations. The results of these experiments show that TRIMHX was correctly implemented and is ready to submit into SCMS production mode.
SOLA-DM: A numerical solution algorithm for transient three-dimensional flows
Wilson, T.L.; Nichols, B.D.; Hirt, C.W.; Stein, L.R.
1988-02-01T23:59:59.000Z
SOLA-DM is a three-dimensional time-explicit, finite-difference, Eulerian, fluid-dynamics computer code for solving the time-dependent incompressible Navier-Stokes equations. The solution algorithm (SOLA) evolved from the marker-and-cell (MAC) method, and the code is highly vectorized for efficient performance on a Cray computer. The computational domain is discretized by a mesh of parallelepiped cells in either cartesian or cylindrical geometry. The primary hydrodynamic variables for approximating the solution of the momentum equations are cell-face-centered velocity components and cell-centered pressures. Spatial accuracy is selected by the user to be first or second order; the time differencing is first-order accurate. The incompressibility condition results in an elliptic equation for pressure that is solved by a conjugate gradient method. Boundary conditions of five general types may be chosen: free-slip, no-slip, continuative, periodic, and specified pressure. In addition, internal mesh specifications to model obstacles and walls are provided. SOLA-DM also solves the equations for discrete particle dynamics, permitting the transport of marker particles or other solid particles through the fluid to be modeled. 7 refs., 7 figs.
THE THREE-DIMENSIONAL STRUCTURE OF CASSIOPEIA A
DeLaney, Tracey [Department of Physics and Engineering, West Virginia Wesleyan College, 59 College Avenue, Buckhannon, WV 26201 (United States); Rudnick, Lawrence; Isensee, Karl, E-mail: delaney_t@wvwc.ed, E-mail: larry@astro.umn.ed, E-mail: isensee@astro.umn.ed [Astronomy Department, University of Minnesota, Minneapolis, MN 55455 (United States)
2010-12-20T23:59:59.000Z
We used the Spitzer Space Telescope's Infrared Spectrograph to map nearly the entire extent of Cassiopeia A between 5 and 40 {mu}m. Using infrared and Chandra X-ray Doppler velocity measurements, along with the locations of optical ejecta beyond the forward shock, we constructed a three-dimensional model of the remnant. The structure of Cas A can be characterized into a spherical component, a tilted thick disk, and multiple ejecta jets/pistons and optical fast-moving knots all populating the thick disk plane. The Bright Ring in Cas A identifies the intersection between the thick plane/pistons and a roughly spherical reverse shock. The ejecta pistons indicate a radial velocity gradient in the explosion. Some ejecta pistons are bipolar with oppositely directed flows about the expansion center while some ejecta pistons show no such symmetry. Some ejecta pistons appear to maintain the integrity of the nuclear burning layers while others appear to have punched through the outer layers. The ejecta pistons indicate a radial velocity gradient in the explosion. In three dimensions, the Fe jet in the southeast occupies a 'hole' in the Si-group emission and does not represent 'overturning', as previously thought. Although interaction with the circumstellar medium affects the detailed appearance of the remnant and may affect the visibility of the southeast Fe jet, the bulk of the symmetries and asymmetries in Cas A are intrinsic to the explosion.
A novel three dimensional semimetallic MoS{sub 2}
Tang, Zhen-Kun [Beijing Computational Science Research Center, Beijing 100084 (China); Departments of Physics and Electronics, Hengyang Normal University, Hengyang 421008 (China); Zhang, Hui; Liu, Li-Min, E-mail: limin.liu@csrc.ac.cn [Beijing Computational Science Research Center, Beijing 100084 (China); Liu, Hao [Chengdu Green Energy and Green Manufacturing Technology R and D Center, Chengdu, Sichuan 610207 (China); Lau, Woon-Ming [Beijing Computational Science Research Center, Beijing 100084 (China); Chengdu Green Energy and Green Manufacturing Technology R and D Center, Chengdu, Sichuan 610207 (China)
2014-05-28T23:59:59.000Z
Transition metal dichalcogenides (TMDs) have many potential applications, while the performances of TMDs are generally limited by the less surface active sites and the poor electron transport efficiency. Here, a novel three-dimensional (3D) structure of molybdenum disulfide (MoS{sub 2}) with larger surface area was proposed based on first-principle calculations. 3D layered MoS{sub 2} structure contains the basal surface and joint zone between the different nanoribbons, which is thermodynamically stable at room temperature, as confirmed by first principles molecular dynamics calculations. Compared the two-dimensional layered structures, the 3D MoS{sub 2} not only owns the large surface areas but also can effectively avoid the aggregation. Interestingly, although the basal surface remains the property of the intrinsic semiconductor as the bulk MoS{sub 2}, the joint zone of 3D MoS{sub 2} exhibits semimetallic, which is derived from degenerate 3d orbitals of the Mo atoms. The high stability, large surface area, and high conductivity make 3D MoS{sub 2} have great potentials as high performance catalyst.
Three-dimensional Casimir piston for massive scalar fields
Lim, S.C. [Faculty of Engineering, Multimedia University, Jalan Multimedia, Cyberjaya 63100, Selangor Darul Ehsan (Malaysia)], E-mail: sclim@mmu.edu.my; Teo, L.P. [Faculty of Information Technology, Multimedia University, Jalan Multimedia, Cyberjaya 63100, Selangor Darul Ehsan (Malaysia)], E-mail: lpteo@mmu.edu.my
2009-08-15T23:59:59.000Z
We consider Casimir force acting on a three-dimensional rectangular piston due to a massive scalar field subject to periodic, Dirichlet and Neumann boundary conditions. Exponential cut-off method is used to derive the Casimir energy. It is shown that the divergent terms do not contribute to the Casimir force acting on the piston, thus render a finite well-defined Casimir force acting on the piston. Explicit expressions for the total Casimir force acting on the piston is derived, which show that the Casimir force is always attractive for all the different boundary conditions considered. As a function of a - the distance from the piston to the opposite wall, it is found that the magnitude of the Casimir force behaves like 1/a{sup 4} when a{yields}0{sup +} and decays exponentially when a{yields}{infinity}. Moreover, the magnitude of the Casimir force is always a decreasing function of a. On the other hand, passing from massless to massive, we find that the effect of the mass is insignificant when a is small, but the magnitude of the force is decreased for large a in the massive case.
Parallel phase-sensitive three-dimensional imaging camera
Smithpeter, Colin L. (Albuquerque, NM); Hoover, Eddie R. (Sandia Park, NM); Pain, Bedabrata (Los Angeles, CA); Hancock, Bruce R. (Altadena, CA); Nellums, Robert O. (Albuquerque, NM)
2007-09-25T23:59:59.000Z
An apparatus is disclosed for generating a three-dimensional (3-D) image of a scene illuminated by a pulsed light source (e.g. a laser or light-emitting diode). The apparatus, referred to as a phase-sensitive 3-D imaging camera utilizes a two-dimensional (2-D) array of photodetectors to receive light that is reflected or scattered from the scene and processes an electrical output signal from each photodetector in the 2-D array in parallel using multiple modulators, each having inputs of the photodetector output signal and a reference signal, with the reference signal provided to each modulator having a different phase delay. The output from each modulator is provided to a computational unit which can be used to generate intensity and range information for use in generating a 3-D image of the scene. The 3-D camera is capable of generating a 3-D image using a single pulse of light, or alternately can be used to generate subsequent 3-D images with each additional pulse of light.
Three Dimensional Simulation of the Baneberry Nuclear Event
Lomov, I
2003-07-16T23:59:59.000Z
Baneberry, a 10-kiloton nuclear event, was detonated at a depth of 278 m at the Nevada Test Site on December 18, 1970. Shortly after detonation, radioactive gases emanating from the cavity were released into the atmosphere through a shock-induced fissure near surface ground zero. Extensive geophysical investigations, coupled with a series of 1D and 2D computational studies were used to reconstruct the sequence of events that led to the catastrophic failure. However, the geological profile of the Baneberry site is complex and inherently three-dimensional, which meant that some geological features had to be simplified or ignored in the 2D simulations. This left open the possibility that features unaccounted for in the 2D simulations could have had an important influence on the eventual containment failure of the Baneberry event. This paper presents results from a high-fidelity 3D Baneberry simulation based on the most accurate geologic and geophysical data available. The results are compared with available data, and contrasted against the results of the previous 2D computational studies.
Models of three-dimensional fractional topological insulators
Joseph Maciejko; Xiao-Liang Qi; Andreas Karch; Shou-Cheng Zhang
2012-12-20T23:59:59.000Z
Time-reversal invariant three-dimensional topological insulators can be defined fundamentally by a topological field theory with a quantized axion angle theta of zero or pi. It was recently shown that fractional quantized values of theta are consistent with time-reversal invariance if deconfined, gapped, fractionally charged bulk excitations appear in the low-energy spectrum due to strong correlation effects, leading to the concept of a fractional topological insulator. These fractionally charged excitations are coupled to emergent gauge fields which ensure that the microscopic degrees of freedom, the original electrons, are gauge-invariant objects. A first step towards the construction of microscopic models of fractional topological insulators is to understand the nature of these emergent gauge theories and their corresponding phases. In this work, we show that low-energy effective gauge theories of both Abelian or non-Abelian type are consistent with a fractional quantized axion angle if they admit a Coulomb phase or a Higgs phase with gauge group broken down to a discrete subgroup. The Coulomb phases support gapless but electrically neutral bulk excitations while the Higgs phases are fully gapped. The Higgs and non-Abelian Coulomb phases exhibit multiple ground states on boundaryless spatial 3-manifolds with nontrivial first homology, while the Abelian Coulomb phase has a unique ground state. The ground state degeneracy receives an additional contribution on manifolds with boundary due to the induced boundary Chern-Simons term.
Effective viscosity of active suspensions: Three-dimensional numerical modeling
Levan Jibuti; Walter Zimmermann; Salima Rafaï; Philippe Peyla
2014-12-10T23:59:59.000Z
A three-dimensional model is proposed for Chlamydomonas Reinhardtii swimming with a breaststroke-like beating of its two flagella. The model reveals unusual angular orbits of the active swimmer under a linear shear flow. Namely, the swimmer sustains orientation transiently across the flow when flagella plane is perpendicular to the shear plane, and amplify the shear-induced rotation along the flow. Such behavior is a result of the interplay between shear-induced deformation and swimmer's periodic beating motion that exerts internal torques on the torque-free swimmer. This particular behavior has some significant consequences on the rheological properties of the suspension that tends to confirm previous experimental results [Phys. Rev. Lett. 104, 098102 (2010)]. We calculated the intrinsic viscosity of the suspension with such isolated modeled microswimmers (dilute case) in shear flow using numerical simulations based on Rotne-Prager approximation. The results show an increased intrinsic viscosity for active swimmer suspensions in comparison to non-active ones in accordance with previous experimental measurements. A major enhancement of the active swimmer viscosity occurs due to the effectively extended shape of the deformable swimming cells. We also recover the experimentally observed shear thinning behavior.
The three-dimensional matrix -- An evolution in project management
Glidewell, D.
1996-09-01T23:59:59.000Z
In the Functional Department Dimension, functional departments such as project management, design, and construction would be maintained to maximize consistency among project teams, evenly allocate training opportunities, and facilitate the crossfeeding of lessons learned and innovative ideas. Functional departments were also determined to be the surest way of complying uniformly with all project control systems required by the Department of Energy (Sandia`s primary external customer). The Technical Discipline dimension was maintained to enhance communication within the technical disciplines, such as electrical engineering, mechanical engineering, civil engineering, etc., and to evenly allocate technical training opportunities, reduce technical obsolescence, and enhance design standards. The third dimension, the Project Dimension, represents the next step in the project management evolution at Sandia, and together with Functional Department and Technical Discipline Dimensions constitutes the three-dimensional matrix. It is this Project Dimension that will be explored thoroughly in this paper, including a discussion of the specific roles and responsibilities of both management and the project team.
Hamiltonian thermodynamics of three-dimensional dilatonic black holes
Dias, Goncalo A. S.; Lemos, Jose P. S. [Centro Multidisciplinar de Astrofisica-CENTRA, Departamento de Fisica, Instituto Superior Tecnico-IST, Universidade Tecnica de Lisboa-UTL, Avenida Rovisco Pais 1, 1049-001 Lisboa (Portugal)
2008-08-15T23:59:59.000Z
The action for a class of three-dimensional dilaton-gravity theories with a negative cosmological constant can be recast in a Brans-Dicke type action, with its free {omega} parameter. These theories have static spherically symmetric black holes. Those with well formulated asymptotics are studied through a Hamiltonian formalism, and their thermodynamical properties are found out. The theories studied are general relativity ({omega}{yields}{infinity}), a dimensionally reduced cylindrical four-dimensional general relativity theory ({omega}=0), and a theory representing a class of theories ({omega}=-3). The Hamiltonian formalism is set up in three dimensions through foliations on the right region of the Carter-Penrose diagram, with the bifurcation 1-sphere as the left boundary, and anti-de Sitter infinity as the right boundary. The metric functions on the foliated hypersurfaces are the canonical coordinates. The Hamiltonian action is written, the Hamiltonian being a sum of constraints. One finds a new action which yields an unconstrained theory with one pair of canonical coordinates (M,P{sub M}), M being the mass parameter and P{sub M} its conjugate momenta The resulting Hamiltonian is a sum of boundary terms only. A quantization of the theory is performed. The Schroedinger evolution operator is constructed, the trace is taken, and the partition function of the canonical ensemble is obtained. The black hole entropies differ, in general, from the usual quarter of the horizon area due to the dilaton.
Three-Dimensional Electromagnetic High Frequency Axisymmetric Cavity Scars.
Warne, Larry K.; Jorgenson, Roy E.
2014-10-01T23:59:59.000Z
This report examines the localization of high frequency electromagnetic fi elds in three-dimensional axisymmetric cavities along periodic paths between opposing sides of the cavity. The cases where these orbits lead to unstable localized modes are known as scars. This report treats both the case where the opposing sides, or mirrors, are convex, where there are no interior foci, and the case where they are concave, leading to interior foci. The scalar problem is treated fi rst but the approximations required to treat the vector fi eld components are also examined. Particular att ention is focused on the normalization through the electromagnetic energy theorem. Both projections of the fi eld along the scarred orbit as well as point statistics are examined. Statistical comparisons are m ade with a numerical calculation of the scars run with an axisymmetric simulation. This axisymmetric cas eformstheoppositeextreme(wherethetwomirror radii at each end of the ray orbit are equal) from the two -dimensional solution examined previously (where one mirror radius is vastly di ff erent from the other). The enhancement of the fi eldontheorbitaxiscanbe larger here than in the two-dimensional case. Intentionally Left Blank
Interactive graphical tools for three-dimensional mesh redistribution
Dobbs, L.A.
1996-03-01T23:59:59.000Z
Three-dimensional meshes modeling nonlinear problems such as sheet metal forming, metal forging, heat transfer during welding, the propagation of microwaves through gases, and automobile crashes require highly refined meshes in local areas to accurately represent areas of high curvature, stress, and strain. These locally refined areas develop late in the simulation and/or move during the course of the simulation, thus making it difficult to predict their exact location. This thesis is a systematic study of new tools scientists can use with redistribution algorithms to enhance the solution results and reduce the time to build, solve, and analyze nonlinear finite element problems. Participatory design techniques including Contextual Inquiry and Design were used to study and analyze the process of solving such problems. This study and analysis led to the in-depth understanding of the types of interactions performed by FEM scientists. Based on this understanding, a prototype tool was designed to support these interactions. Scientists participated in evaluating the design as well as the implementation of the prototype tool. The study, analysis, prototype tool design, and the results of the evaluation of the prototype tool are described in this thesis.
Lyapunov modes in three-dimensional Lennard-Jones fluids
M. Romero-Bastida; E. Braun
2008-07-15T23:59:59.000Z
Recent studies on the phase-space dynamics of a one-dimensional Lennard-Jones fluid reveal the existence of regular collective perturbations associated with the smallest positive Lyapunov exponents of the system, called hydrodynamic Lyapunov modes, which previously could only be identified in hard-core fluids. In this work we present a systematic study of the Lyapunov exponents and Lyapunov vectors, i.e. perturbations along each direction of phase space, of a three-dimensional Lennard-Jones fluid. By performing the Fourier transform of the spatial density of the coordinate part of the Lyapunov vector components and then time-averaging this result we find convincing signatures of longitudinal modes, with inconclusive evidence of transverse modes for all studied densities. Furthermore, the longitudinal modes can be more clearly identified for the higher density values. Thus, according to our results, the mixing of modes induced both by the dynamics and the dimensionality induce a hitherto unknown type of order in the tangent space of the model herein studied at high density values.
Three-dimensional hydrodynamic simulations of the combustion of a neutron star into a quark star
Matthias Herzog; Friedrich K. Roepke
2011-09-02T23:59:59.000Z
We present three-dimensional numerical simulations of turbulent combustion converting a neutron star into a quark star. Hadronic matter, described by a micro-physical finite-temperature equation of state, is converted into strange quark matter. We assume this phase, represented by a bag-model equation of state, to be absolutely stable. Following the example of thermonuclear burning in white dwarfs leading to Type Ia supernovae, we treat the conversion process as a potentially turbulent deflagration. Solving the non-relativistic Euler equations using established numerical methods we conduct large eddy simulations including an elaborate subgrid scale model, while the propagation of the conversion front is modeled with a level-set method. Our results show that for large parts of the parameter space the conversion becomes turbulent and therefore significantly faster than in the laminar case. Despite assuming absolutely stable strange quark matter, in our hydrodynamic approximation an outer layer remains in the hadronic phase, because the conversion front stops when it reaches conditions under which the combustion is no longer exothermic.
Three-dimensional induced polarization data inversion for complex resistivity
Commer, M.; Newman, G.A.; Williams, K.H.; Hubbard, S.S.
2011-03-15T23:59:59.000Z
The conductive and capacitive material properties of the subsurface can be quantified through the frequency-dependent complex resistivity. However, the routine three-dimensional (3D) interpretation of voluminous induced polarization (IP) data sets still poses a challenge due to large computational demands and solution nonuniqueness. We have developed a flexible methodology for 3D (spectral) IP data inversion. Our inversion algorithm is adapted from a frequency-domain electromagnetic (EM) inversion method primarily developed for large-scale hydrocarbon and geothermal energy exploration purposes. The method has proven to be efficient by implementing the nonlinear conjugate gradient method with hierarchical parallelism and by using an optimal finite-difference forward modeling mesh design scheme. The method allows for a large range of survey scales, providing a tool for both exploration and environmental applications. We experimented with an image focusing technique to improve the poor depth resolution of surface data sets with small survey spreads. The algorithm's underlying forward modeling operator properly accounts for EM coupling effects; thus, traditionally used EM coupling correction procedures are not needed. The methodology was applied to both synthetic and field data. We tested the benefit of directly inverting EM coupling contaminated data using a synthetic large-scale exploration data set. Afterward, we further tested the monitoring capability of our method by inverting time-lapse data from an environmental remediation experiment near Rifle, Colorado. Similar trends observed in both our solution and another 2D inversion were in accordance with previous findings about the IP effects due to subsurface microbial activity.
Three-dimensional P and S waves velocity structures of the Coso...
search OpenEI Reference LibraryAdd to library Journal Article: Three-dimensional P and S waves velocity structures of the Coso geothermal area, California, from...
alter three-dimensional collagen: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Peeters, Arthur; Zarzoso, David; Poli, Emanuele; Casson, Francis 2014-01-01 499 NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration Engineering Websites Summary: NISTIR...
advanced three-dimensional environmental: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Peeters, Arthur; Zarzoso, David; Poli, Emanuele; Casson, Francis 2014-01-01 498 NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration Engineering Websites Summary: NISTIR...
anatomic-based three-dimensional planning: Topics by E-print...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Peeters, Arthur; Zarzoso, David; Poli, Emanuele; Casson, Francis 2014-01-01 484 NISTIR 7232 CEMHYD3D: A Three-Dimensional Cement Hydration Engineering Websites Summary: NISTIR...
Chien, T.H.; Domanus, H.M.; Sha, W.T.
1993-02-01T23:59:59.000Z
The COMMIX-PPC computer pregrain is an extended and improved version of earlier COMMIX codes and is specifically designed for evaluating the thermal performance of power plant condensers. The COMMIX codes are general-purpose computer programs for the analysis of fluid flow and heat transfer in complex Industrial systems. In COMMIX-PPC, two major features have been added to previously published COMMIX codes. One feature is the incorporation of one-dimensional equations of conservation of mass, momentum, and energy on the tube stile and the proper accounting for the thermal interaction between shell and tube side through the porous-medium approach. The other added feature is the extension of the three-dimensional conservation equations for shell-side flow to treat the flow of a multicomponent medium. COMMIX-PPC is designed to perform steady-state and transient. Three-dimensional analysis of fluid flow with heat transfer tn a power plant condenser. However, the code is designed in a generalized fashion so that, with some modification, it can be used to analyze processes in any heat exchanger or other single-phase engineering applications. Volume I (Equations and Numerics) of this report describes in detail the basic equations, formulation, solution procedures, and models for a phenomena. Volume II (User's Guide and Manual) contains the input instruction, flow charts, sample problems, and descriptions of available options and boundary conditions.
Inverse medium scattering for three-dimensional time harmonic ...
2004-01-22T23:59:59.000Z
Jan 22, 2004 ... problem of time harmonic Maxwell equations in R3. ..... For a simple stability analysis, some relative random noise is added to the data, e.g., the.
Prellberg, Thomas
of three-dimensional lattice trails Andrea Bedini* and Aleksander L. Owczarek Department of Mathematics
Atomic Scale Design and Three-Dimensional Simulation of Ionic Diffusive Nanofluidic Channels
Jin Kyoung Park; Kelin Xia; Guo-Wei We
2015-03-02T23:59:59.000Z
Recent advance in nanotechnology has led to rapid advances in nanofluidics, which has been established as a reliable means for a wide variety of applications, including molecular separation, detection, crystallization and biosynthesis. Although atomic and molecular level consideration is a key ingredient in experimental design and fabrication of nanfluidic systems, atomic and molecular modeling of nanofluidics is rare and most simulations at nanoscale are restricted to one- or two-dimensions in the literature, to our best knowledge. The present work introduces atomic scale design and three-dimensional (3D) simulation of ionic diffusive nanofluidic systems. We propose a variational multiscale framework to represent the nanochannel in discrete atomic and/or molecular detail while describe the ionic solution by continuum. Apart from the major electrostatic and entropic effects, the non-electrostatic interactions between the channel and solution, and among solvent molecules are accounted in our modeling. We derive generalized Poisson-Nernst-Planck (PNP) equations for nanofluidic systems. Mathematical algorithms, such as Dirichlet to Neumann mapping and the matched interface and boundary (MIB) methods are developed to rigorously solve the aforementioned equations to the second-order accuracy in 3D realistic settings. Three ionic diffusive nanofluidic systems, including a negatively charged nanochannel, a bipolar nanochannel and a double-well nanochannel are designed to investigate the impact of atomic charges to channel current, density distribution and electrostatic potential. Numerical findings, such as gating, ion depletion and inversion, are in good agreements with those from experimental measurements and numerical simulations in the literature.
Ris-M-2209 THE THREE-DIMENSIONAL PWR TRANSIENT CODE
, REACTOR KINETICS, ROD DROP ACCIDENTS, THREE- DIMENSIONAL CALCULATIONS, TRANSIENTS. UDC 621 more or less by change. The calculation is there- fore not representative of any existing reactorRisÃ¸-M-2209 THE THREE-DIMENSIONAL PWR TRANSIENT CODE ANTI; ROD EJECTION TEST CALCULATION A
ON THE DERIVATION OF NONLINEAR SHELL MODELS FROM THREE-DIMENSIONAL ELASTICITY
, 74G10, 74G65. Key words and phrases. Elasticity, shells, energy minimization, Koiter. hal-00392028ON THE DERIVATION OF NONLINEAR SHELL MODELS FROM THREE-DIMENSIONAL ELASTICITY Cristinel Mardare. A nonlinearly elastic shell is modeled either by the nonlinear three- dimensional shell model or by a nonlinear
A THREE DIMENSIONAL FINITE VOLUME APPROACH TO THE THERMO-MECHANICAL
Taylor, Gary
A THREE DIMENSIONAL FINITE VOLUME APPROACH TO THE THERMO-MECHANICAL MODELLING OF THE SHAPE CASTING a three dimensional, thermo-mechanical modelling approach to the cooling and solidi cation phases the non-linear material phenomena of creep and thermo-elasto-visco-plasticity at high temperatures
Three-Dimensional Computer Graphics Architecture Tulika Mitra Tzi-cker Chiueh
Mitra, Tulika
Three-Dimensional Computer Graphics Architecture Tulika Mitra Tzi-cker Chiueh Computer Science,chiuehg@cs.sunysb.edu March 7, 2000 Abstract Three-dimensional (3D) computer graphics hardware has emerged to become an integral part of mainstream desktop PC systems. The aim of this paper is to describe the 3D graphics
Three-dimensional imaging of skin melanoma in vivo by dual-wavelength photoacoustic microscopy
Wang, Lihong
Three-dimensional imaging of skin melanoma in vivo by dual-wavelength photoacoustic microscopy Jung to noninvasively obtain three-dimensional 3-D images of subcutaneous melanomas and their surrounding vasculature in nude mice in vivo. The absorption coefficients of blood and melanin- pigmented melanomas vary greatly
Three-dimensional spectral element simulations of variable density and viscosity, miscible
Meiburg, Eckart H.
are encountered under a wide variety of circumstances, ranging from lubrication applications to enhanced oil very slow flows display significant three-dimensional effects. As a result, the early axisymmetric the observed differences. Hence, the possible role of three-dimensional flow effects in this parameter ran
MICROFABRICATED, ULTRA-DENSE, THREE-DIMENSIONAL METAL COILS F. Herrault1*
to form a three-dimensional coil device. The MEMS- fabricated, ultra-dense coils exhibited a 62% improvement in packing density over conventional wire-wound coils. KEYWORDS Micro-coils, chemical vapor of these microstructures to form a three-dimensional coil device. The polymer material provides electrical insulation
Ritchie, Robert
, Thousand Oaks, CA 91360 Three-dimensional (3-D) images of two ceramic-matrix textile composites were studied represent a new class of integrally woven ceramic matrix composites for high-temperature appliCharacterizing Three-Dimensional Textile Ceramic Composites Using Synchrotron X-Ray Micro
Planar Waveguide-Nanowire Integrated Three-Dimensional Dye-Sensitized Solar Cells
Wang, Zhong L.
Planar Waveguide-Nanowire Integrated Three-Dimensional Dye-Sensitized Solar Cells Yaguang Wei, Chen to fabricate three-dimensional (3D) dye-sensitized solar cells (DSSCs) by integrating planar optical waveguide cells that can be expanded to organic- and inorganic-based solar cells. KEYWORDS Dye-sensitized solar
Three-dimensional mapping of optical near field of a nanoscale bowtie antenna
Xu, Xianfan
Three-dimensional mapping of optical near field of a nanoscale bowtie antenna Rui Guo*, Edward C. This paper describes an experimental three-dimensional optical near-field mapping of a bowtie nano. The experimental results also demonstrate the polarization dependence of the transmission through the bowtie
Vermont, University of
Addressing model bias and uncertainty in three dimensional groundwater transport forecasts, and D. M. Rizzo (2008), Addressing model bias and uncertainty in three dimensional groundwater transport. Introduction [2] Eigbe et al. [1998] provide an excellent review of groundwater applications of the linear
Relation Between Structure, Function, and Imaging in a Three-Dimensional Model of the Lung
Lutchen, Kenneth
Relation Between Structure, Function, and Imaging in a Three-Dimensional Model of the Lung NORA T morphometric mod- els to predict function relations in the lung. These models, however, are not anatomically explicit. We have advanced a three-dimensional airway tree model to relate dynamic lung function
Liu, Hongyu
Radiative effect of clouds on tropospheric chemistry in a global three-dimensional chemical. (2006), Radiative effect of clouds on tropospheric chemistry in a global three-dimensional chemical frequencies are calculated using the Fast-J radiative transfer algorithm. The GEOS-3 global cloud optical
Three-dimensional SPH simulations of accretion discs
Henri M. J. Boffin; Kei Haraguchi; Takuya Matsuda
1998-12-01T23:59:59.000Z
We discuss some 3D numerical simulations of accretion discs using the SPH method and a polytropic equation of state. We show that discs exist even for as large value of the polytropic index as 1.2, and that these discs are always in hydrostatic balance. We also show that even without any inflow, spiral shocks appear in the discs.
Diffusion coefficient of three-dimensional Yukawa liquids
Dzhumagulova, K. N.; Ramazanov, T. S.; Masheeva, R. U. [IETP, Al Farabi Kazakh National University, 71, al Farabi ave., Almaty 050040 (Kazakhstan)] [IETP, Al Farabi Kazakh National University, 71, al Farabi ave., Almaty 050040 (Kazakhstan)
2013-11-15T23:59:59.000Z
The purpose of this work is an investigation of the diffusion coefficient of the dust component in complex plasma. The computer simulation of the Yukawa liquids was made on the basis of the Langevin equation, which takes into account the influence of buffer plasma on the dust particles dynamics. The Green–Kubo relation was used to calculate the diffusion coefficient. Calculations of the diffusion coefficient for a wide range of the system parameters were performed. Using obtained numerical data, we constructed the interpolation formula for the diffusion coefficient. We also show that the interpolation formula correctly describes experimental data obtained under microgravity conditions.
Characterizing three-dimensional groundwater flow and transport
Hollenshead, Jeromy Todd
1995-01-01T23:59:59.000Z
) linearize the gov- erning steady state flow equations to improve the description of the stochastic structure of the permeability distribution. A similar analytical approach is taken by Dagan (1985). Es- timates based on the maximum likelihood method... that regarded permeability ss a random variable were obtained in Loaiciga and Marino (1987a) and Loaiciga and Marino (1987b) who used a two-stage least-squares method, Rubln and Dagan (1987a), Rubin and Dagan (1987b), and Lu et al. (1988) who used a...
Three dimensional thermal-solute phase field simulation of binary alloy solidification
P. C. Bollada; C. E. Goodyer; P. K. Jimack; A. M. Mullis; F. W. Yang
2014-09-22T23:59:59.000Z
We employ adaptive mesh refinement, implicit time stepping, a nonlinear multigrid solver and parallel computation, to solve a multi-scale, time dependent, three dimensional, nonlinear set of coupled partial differential equations for three scalar field variables. The mathematical model represents the non-isothermal solidification of a metal alloy into a melt substantially cooled below its freezing point at the microscale. Underlying physical molecular forces are captured at this scale by a specification of the energy field. The time rate of change of the temperature, alloy concentration and an order parameter to govern the state of the material (liquid or solid) is controlled by the diffusion parameters and variational derivatives of the energy functional. The physical problem is important to material scientists for the development of solid metal alloys and, hitherto, this fully coupled thermal problem has not been simulated in three dimensions, due to its computationally demanding nature. By bringing together state of the art numerical techniques this problem is now shown here to be tractable at appropriate resolution with relatively moderate computational resources.
Cao, Miaomiao, E-mail: mona486@yeah.net; Li, Ke, E-mail: like3714@163.com [Key Laboratory of High Power Microwave Sources and Technologies, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190 (China) [Key Laboratory of High Power Microwave Sources and Technologies, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Liu, Wenxin, E-mail: lwenxin@mail.ie.ac.cn; Wang, Yong, E-mail: wangyong3845@sina.com [Key Laboratory of High Power Microwave Sources and Technologies, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190 (China)] [Key Laboratory of High Power Microwave Sources and Technologies, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190 (China)
2014-02-15T23:59:59.000Z
In this paper, a dielectric-loaded grating for Smith-Purcell device is proposed. The three-dimensional (3D) analytical theory for hot dispersion relation is obtained by using field matched method, which is solved by numerical simulations. The first and second order growth rates for the proposal model are analyzed, which is obtained by expanding hot dispersion equation at the operating point. The results show that the dispersion can be effectively weakened by introducing dielectric-loaded grating, in which the cutoff frequency is affected by the grating thickness. The dispersion curve becomes flatter and shifts towards lower frequency at the optimum grating parameters. The 3D particle-in-cell (PIC) simulation is also performed and the results are in good agreement with theoretical calculations. Comparing the first order growth rate with the second one, it reveals that the discrepancy is small when electron beam parameters are selected with small values. Otherwise, the discrepancy is large and cannot be ignored. To accurately describe the process of beam-wave interaction, the second order growth rate is necessary to apply.
Schiek, Richard (Albuquerque, NM)
2006-06-20T23:59:59.000Z
A method of generating two-dimensional masks from a three-dimensional model comprises providing a three-dimensional model representing a micro-electro-mechanical structure for manufacture and a description of process mask requirements, reducing the three-dimensional model to a topological description of unique cross sections, and selecting candidate masks from the unique cross sections and the cross section topology. The method further can comprise reconciling the candidate masks based on the process mask requirements description to produce two-dimensional process masks.
Esmen, Ekrem Alp, 1977-
2004-01-01T23:59:59.000Z
Three-dimensional mixed-mode linear elastic fracture mechanics analysis is presented using domain interaction integrals. An out-of-plane sinusoidal crack was analyzed using a commercially available finite element package ...
THREE-DIMENSIONAL METALLIC ARCHITECTURES FOR PHOTONIC AND ENERGY STORAGE APPLICATIONS
Braun, Paul
THREE-DIMENSIONAL METALLIC ARCHITECTURES FOR PHOTONIC AND ENERGY STORAGE APPLICATIONS BY KEVIN interesting for photonic and energy storage applications. Sacrificial templates are commonly used metamaterial, and energy storage applications. 3D metallic architectures are useful for solar
Gregorski, Steven Joseph
1996-01-01T23:59:59.000Z
The material properties and dimensional accuracy of metal tooling produced by the Three Dimensional Printing process can be enhanced by increasing the green density of the 3D printed part. Green density is the ratio of ...
Electrons Move Like Light in Three-Dimensional Solid | U.S. DOE...
Office of Science (SC) Website
Electrons Move Like Light in Three-Dimensional Solid Tracking electronic motion in a graphene-like bulk material shows fast electrons in all dimensions. Print Text Size: A A A...
Fabrication of complex oral drug delivery forms by Three Dimensional Printing (tm)
Katstra, Wendy E. (Wendy Ellen), 1974-
2001-01-01T23:59:59.000Z
Three Dimensional Printing 3DPTM is a novel solid freeform fabrication technology that has been applied to the fabrication of complex pharmaceutical drug devices. Limitations of the technology as relating to pharmaceuticals ...
Bimetallic bars with local control of composition by three-dimensional printing
Techapiesancharoenkij, Ratchatee, 1979-
2004-01-01T23:59:59.000Z
Three Dimensional Printing (3DP) is a process that enables the fabrication of geometrically complex parts directly from computer-aided design (CAD) models. The success of 3DP as an alternative manufacturing technology to ...
Three-dimensional and two-dimensional deployment analysis for underwater acoustic sensor networks q
Pompili, Dario
Three-dimensional and two-dimensional deployment analysis for underwater acoustic sensor networks q Accepted 23 July 2008 Available online 7 August 2008 Keywords: Underwater acoustic sensor networks data collection, pollution monitoring, offshore exploration, disaster prevention, assisted navigation
Three-dimensional cardiac architecture determined by two-photon microtomy
Huang, Hayden
Cardiac architecture is inherently three-dimensional, yet most characterizations rely on two-dimensional histological slices or dissociated cells, which remove the native geometry of the heart. We previously developed a ...
Interferometric-spatial-phase imaging for sub-nanometer three-dimensional positioning
Moon, Euclid E. (Euclid Eberle), 1965-
2004-01-01T23:59:59.000Z
Current alignment technology is incapable of satisfying the needs of imminent generations of lithography. This dissertation delineates a novel method of alignment and three-dimensional position metrology that is compatible ...
Green Water Flow Kinematics and Impact Pressure on a Three Dimensional Model Structure
Ariyarathne, Hanchapola Appuhamilage Kusalika Suranjani
2011-10-21T23:59:59.000Z
Flow kinematics of green water due to plunging breaking waves interacting with a simplified, three-dimensional model structure was investigated in laboratory. Two breaking wave conditions were tested: one with waves impinging and breaking...
Shmelev, Alexey Alexandrovich
2011-01-01T23:59:59.000Z
This thesis describes the physics of fully three-dimensional low frequency acoustic interaction with internal waves, bottom sediment waves and surface swell waves that are often observed in shallow waters and on continental ...
Ensemble Analysis of Angiogenic Growth in Three-Dimensional Microfluidic Cell Cultures
Farahat, Waleed A.
We demonstrate ensemble three-dimensional cell cultures and quantitative analysis of angiogenic growth from uniform endothelial monolayers. Our approach combines two key elements: a micro-fluidic assay that enables ...
Fucetola, Corey Patrick
2013-01-01T23:59:59.000Z
This thesis considers the viability of nanomembrane handling and stacking approaches to enable the fabrication of three-dimensional (3D) nano-structured materials. Sequentially stacking previously-patterned membranes to ...
Monolithic three-dimensional electrochemical energy storage system on aerogel or nanotube scaffold
Farmer, Joseph C; Stadermann, Michael
2013-11-12T23:59:59.000Z
A monolithic three-dimensional electrochemical energy storage system is provided on an aerogel or nanotube scaffold. An anode, separator, cathode, and cathodic current collector are deposited on the aerogel or nanotube scaffold.
Monolithic three-dimensional electrochemical energy storage system on aerogel or nanotube scaffold
Farmer, Joseph Collin; Stadermann, Michael
2014-07-15T23:59:59.000Z
A monolithic three-dimensional electrochemical energy storage system is provided on an aerogel or nanotube scaffold. An anode, separator, cathode, and cathodic current collector are deposited on the aerogel or nanotube scaffold.
Characterization and requirements for Cu-Cu bonds for three-dimensional integrated circuits
Tadepalli, Rajappa, 1979-
2007-01-01T23:59:59.000Z
Three-dimensional integrated circuit (3D IC) technology enables heterogeneous integration of devices fabricated from different technologies, and reduces global RC delay by increasing the device density per unit chip area. ...
Modeling of three-dimensional viscoelastic flows with free surfaces using a finite element method
Adrian, David Joseph
2010-01-01T23:59:59.000Z
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 ...
Calabro, Joshua D.
Fundamental to the development of three-dimensional microelectronic fabrication is a material that enables vertical geometries. Here we show low-melting-point metal alloys containing iron dispersions that can be remotely ...
Yamazaki, Kazuo [Department of Mathematics, Oklahoma State University, 401 Mathematical Sciences, Stillwater, Oklahoma 74078 (United States)] [Department of Mathematics, Oklahoma State University, 401 Mathematical Sciences, Stillwater, Oklahoma 74078 (United States)
2014-03-15T23:59:59.000Z
We study the three-dimensional magnetohydrodynamics system and obtain its regularity criteria in terms of only two velocity vector field components eliminating the condition on the third component completely. The proof consists of a new decomposition of the four nonlinear terms of the system and estimating a component of the magnetic vector field in terms of the same component of the velocity vector field. This result may be seen as a component reduction result of many previous works [C. He and Z. Xin, “On the regularity of weak solutions to the magnetohydrodynamic equations,” J. Differ. Equ. 213(2), 234–254 (2005); Y. Zhou, “Remarks on regularities for the 3D MHD equations,” Discrete Contin. Dyn. Syst. 12(5), 881–886 (2005)].
Three-Dimensional Reconstruction of Porous LSCF Cathodes D. Gostovic,*,z
Florida, University of
Three-Dimensional Reconstruction of Porous LSCF Cathodes D. Gostovic,*,z J. R. Smith,* D. P In this initial study the electrochemically active region of a La0.8Sr0.2Co0.2Fe0.8O3- LSCF cathode an actual three-dimensional 3D model of a La0.8Sr0.2Co0.2Fe0.8O3- LSCF cathode and its interface
Effect of pressure gradient on the drag reduction performance of two and three dimensional riblets
Hall, Aaron Chenault
1991-01-01T23:59:59.000Z
EFFECT OF PRESSURE GRADIENT ON THE DRAG REDUCTION PERFORMANCE OF TWO AND THREE DIMENSIONAL RIBLETS A Thesis by AARON CHENAULT HALL 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 1991 Major Subject: Aerospace Engineering EFFECT OF PRESSURE GRADIENT ON THE DRAG REDUCTION PERFORMANCE OF TWO AND THREE DIMENSIONAL RIBLETS A Thesis by AARON CHENAULT HALL Approved as to style and content by...
Three-dimensional whispering gallery modes in InGaAs nanoneedle lasers on silicon
Tran, T.-T. D.; Chen, R.; Ng, K. W.; Ko, W. S.; Lu, F.; Chang-Hasnain, C. J., E-mail: cch@berkeley.edu [Applied Science and Technology Group and Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720 (United States)
2014-09-15T23:59:59.000Z
As-grown InGaAs nanoneedle lasers, synthesized at complementary metal–oxide–semiconductor compatible temperatures on polycrystalline and crystalline silicon substrates, were studied in photoluminescence experiments. Radiation patterns of three-dimensional whispering gallery modes were observed upon optically pumping the needles above the lasing threshold. Using the radiation patterns as well as finite-difference-time-domain simulations and polarization measurements, all modal numbers of the three-dimensional whispering gallery modes could be identified.
Yang, Yu-Hsiang
1998-01-01T23:59:59.000Z
EXPERIMENTAL STUDY ON BUBBLE COLLAPSE PHENOMENA IN SUBCOOLED WATER WITH THREE-DIMENSIONAL PARTICLE IMAGE VELOCIMETRY A Thesis by YU-HSIANG YANG 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 1998 Major Subject: Nuclear Engineering EXPERIMENTAL STUDY ON BUBBLE COLLAPSE PHENOMENA IN SUBCOOLED WATER WITH THREE-DIMENSIONAL PARTICLE IMAGE VELOCIMETRY A Thesis by YU-HSIANG YANG Submitted...
Guo, David, 1976-
2004-01-01T23:59:59.000Z
Three Dimensional Printing (3DP) is a solid freeform fabrication process used to generate solid parts directly from three-dimensional computer models. A part geometry is created by selectively depositing binder into ...
Lawrence, R.D.
1983-03-01T23:59:59.000Z
A nodal method is developed for the solution of the neutron-diffusion equation in two- and three-dimensional hexagonal geometries. The nodal scheme has been incorporated as an option in the finite-difference diffusion-theory code DIF3D, and is intended for use in the analysis of current LMFBR designs. The nodal equations are derived using higher-order polynomial approximations to the spatial dependence of the flux within the hexagonal-z node. The final equations, which are cast in the form of inhomogeneous response-matrix equations for each energy group, involved spatial moments of the node-interior flux distribution plus surface-averaged partial currents across the faces of the node. These equations are solved using a conventional fission-source iteration accelerated by coarse-mesh rebalance and asymptotic source extrapolation. This report describes the mathematical development and numerical solution of the nodal equations, as well as the use of the nodal option and details concerning its programming structure. This latter information is intended to supplement the information provided in the separate documentation of the DIF3D code.
FROM NORLUND MATRICES TO LAPLACE REPRESENTATIONS
Sinnamon, Gordon J.
(and not too large) on the line Re z = 0, the Laplace transform LF is just the (Poisson extension of the) Fourier transform of F. It is therefore appropriate to view the power series representation¨orlund matrices and corresponding convolution operators on the line. Analogous inequalities are proved for power
Cloaking a sensor for three-dimensional Maxwell's equations: transformation optics approach
Chen, Xudong; Uhlmann, Gunther
2011-01-01T23:59:59.000Z
P. Sheng, “Transformation optics and metamaterials,” Nat.sensor via transformation optics,” Phys. Rev. E 83, 016603 (October 2011 / Vol. 19, No. 21 / OPTICS EXPRESS 20518 13. G.
El-Taibany, W. F.; El-Shamy, E. F. [Department of Physics, Faculty of Science, Mansoura University, Damietta Branch, P.O. 34517, Damietta El-Gedida (Egypt); El-Bedwehy, N. A. [Department of Mathematics, Faculty of Science, Mansoura University, Damietta Branch, P.O. 34517, Damietta El-Gedida (Egypt)
2011-03-15T23:59:59.000Z
Using the small-k expansion perturbation method, the three-dimensional stability of dust-ion acoustic solitary waves (DIASWs) in a magnetized multicomponent dusty plasma containing negative heavy ions and stationary variable-charge dust particles is analyzed. A nonlinear Zakharov-Kuznetsov equation adequate for describing these solitary structures is derived. Moreover, the basic features of the DIASWs are studied. The determination of the stability region leads to two different cases depending on the oblique propagation angle. In addition, the growth rate of the produced waves is estimated. The increase of either the negative ion number density or their temperatures or even the number density of the dust grains results in reducing the wave growth rate. Finally, the present results should elucidate the properties of DIASWs in a multicomponent plasma with negative ions, particularly in laboratory experiment and plasma process.
Nonlinear electron-magnetohydrodynamic simulations of three dimensional current shear instability
Jain, Neeraj [Max Planck Institute for Solar System Research, Max-Planck-Str. 2, 37191 Katlenburg-Lindau (Germany); Das, Amita; Sengupta, Sudip; Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)
2012-09-15T23:59:59.000Z
This paper deals with detailed nonlinear electron-magnetohydrodynamic simulations of a three dimensional current shear driven instability in slab geometry. The simulations show the development of the instability in the current shear layer in the linear regime leading to the generation of electromagnetic turbulence in the nonlinear regime. The electromagnetic turbulence is first generated in the unstable shear layer and then spreads into the stable regions. The turbulence spectrum shows a new kind of anisotropy in which power transfer towards shorter scales occurs preferentially in the direction perpendicular to the electron flow. Results of the present three dimensional simulations of the current shear instability are compared with those of our earlier two dimensional simulations of sausage instability. It is found that the flattening of the mean velocity profile and thus reduction in the electron current due to generation of electromagnetic turbulence in the three dimensional case is more effective as compared to that in the two dimensional case.
Zaleski, T. A.; Polak, T. P. [Institute of Low Temperatures and Structure Research, Polish Academy of Sciences, POB 1410, 50-950 Wroclaw 2 (Poland); Adam Mickiewicz University of Poznan, Faculty of Physics, Umultowska 85, 61-614 Poznan (Poland)
2011-02-15T23:59:59.000Z
We discuss a system of dilute Bose gas confined in a layered structure of stacked square lattices (slab geometry). A derived phase diagram reveals a nonmonotonic dependence of the ratio of tunneling to on-site repulsion on the artificial magnetic field applied to the system. The effect is reduced when more layers are added, which mimics a two- to quasi-three-dimensional geometry crossover. Furthermore, we establish a correspondence between anisotropic infinite (quasi-three-dimensional) and isotropic finite (slab geometry) systems that share exactly the same critical values, which can be an important clue for choosing experimental setups that are less demanding, but still leading to the identical results. Finally, we show that the properties of the ideal Bose gas in a three-dimensional optical lattice can be closely mimicked by finite (slab) systems when the number of two-dimensional layers is larger than 10 for isotropic interactions, or even less when the layers are weakly coupled.
Thorne, P.D.; Chamness, M.A.; Spane, F.A. Jr.; Vermeul, V.R.; Webber, W.D.
1993-12-01T23:59:59.000Z
The ground water underlying parts of the Hanford Site (Figure 1.1) contains radioactive and chemical contaminants at concentrations exceeding regulatory standards (Dresel et al. 1993). The Hanford Site Ground-Water Surveillance Project, operated by Pacific Northwest Laboratory (PNL), is responsible for monitoring the movement of these contaminants to ensure that public health and the environment are protected. To support the monitoring effort, a sitewide three-dimensional ground-water flow model is being developed. This report provides an update on the status of the conceptual model that will form the basis for constructing a numerical three-dimensional flow model for, the site. Thorne and Chamness (1992) provide additional information on the initial development of the three-dimensional conceptual model.
Karasick, M.S.; Strip, D.R.
1996-01-30T23:59:59.000Z
A parallel computing system is described that comprises a plurality of uniquely labeled, parallel processors, each processor capable of modeling a three-dimensional object that includes a plurality of vertices, faces and edges. The system comprises a front-end processor for issuing a modeling command to the parallel processors, relating to a three-dimensional object. Each parallel processor, in response to the command and through the use of its own unique label, creates a directed-edge (d-edge) data structure that uniquely relates an edge of the three-dimensional object to one face of the object. Each d-edge data structure at least includes vertex descriptions of the edge and a description of the one face. As a result, each processor, in response to the modeling command, operates upon a small component of the model and generates results, in parallel with all other processors, without the need for processor-to-processor intercommunication. 8 figs.
Ray tracing a three-dimensional scene using a hierarchical data structure
Wald, Ingo; Boulos, Solomon; Shirley, Peter
2012-09-04T23:59:59.000Z
Ray tracing a three-dimensional scene made up of geometric primitives that are spatially partitioned into a hierarchical data structure. One example embodiment is a method for ray tracing a three-dimensional scene made up of geometric primitives that are spatially partitioned into a hierarchical data structure. In this example embodiment, the hierarchical data structure includes at least a parent node and a corresponding plurality of child nodes. The method includes a first act of determining that a first active ray in the packet hits the parent node and a second act of descending to each of the plurality of child nodes.
Geometry and scaling of tangled vortex lines in three-dimensional random wave fields
Alexander J. Taylor; Mark R. Dennis
2015-01-20T23:59:59.000Z
The short- and long-scale behaviour of tangled wave vortices (nodal lines) in random three-dimensional wave fields is studied via computer experiment. The zero lines are tracked in numerical simulations of periodic superpositions of three-dimensional complex plane waves. The probability distribution of local geometric quantities such as curvature and torsion are compared to previous analytical and new Monte Carlo results from the isotropic Gaussian random wave model. We further examine the scaling and self-similarity of tangled wave vortex lines individually and in the bulk, drawing comparisons with other physical systems of tangled filaments.
Waveguides in three-dimensional metallic photonic band-gap materials
Sigalas, M.M.; Biswas, R.; Ho, K.M.; Soukoulis, C.M. [Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States)] [Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States); Crouch, D.D. [Advanced Electromagnetic Technologies Center, Raytheon Corporation, Rancho Cucamonga, California 91729 (United States)] [Advanced Electromagnetic Technologies Center, Raytheon Corporation, Rancho Cucamonga, California 91729 (United States)
1999-08-01T23:59:59.000Z
We theoretically investigate waveguide structures in three-dimensional metallic photonic band-gap (MPBG) materials. The MPBG materials used in this study consist of a three-dimensional mesh of metallic wires embedded in a dielectric. An {ital L}-shaped waveguide is created by removing part of the metallic wires. Using finite difference time domain simulations, we found that an 85{percent} transmission efficiency can be achieved through the 90{degree} bend with just three unit cell thickness MPBG structures. thinsp {copyright} {ital 1999} {ital The American Physical Society}
Landy, N I; Smith, D R
2010-01-01T23:59:59.000Z
We introduce an approach to the design of three-dimensional transformation optical (TO) media based on a generalized quasi-conformal mapping approach. The generalized quasi-conformal TO (QCTO) approach enables the design of media that can, in principle, be broadband and low-loss, while controlling the propagation of waves with arbitrary angles of incidence and polarization. We illustrate the method in the design of a three-dimensional "carpet" ground plane cloak and of a flattened Luneburg lens. Ray-trace studies provide a confirmation of the performance of the QCTO media, while also revealing the limited performance of index-only versions of these devices.
Three-dimensional Modeling of Acid Transport and Etching in a Fracture
Oeth, Cassandra V
2013-11-25T23:59:59.000Z
’s conductivity, which is based on the etched width created by the injected acid. Etching occurs along the fracture surface but is based on acid flowing through the fracture, so an evaluation tool should describe three-dimensional physics and chemistry. Current...
MICROSCALE THREE-DIMENSIONAL HEMISPHERICAL SHELL RESONATORS FABRICATED FROM METALLIC GLASS
M'Closkey, Robert T.
MICROSCALE THREE-DIMENSIONAL HEMISPHERICAL SHELL RESONATORS FABRICATED FROM METALLIC GLASS M. Kanik.S. Abstract-- A novel use of bulk metallic glasses in microresonator applications is reported and a method scale glass blowmolding using quartz [2] and Pyrex [3], as well as the isotropic etching of silicon
Three-Dimensional Hydrodynamic Model for Prediction of Falling Cylinder Through Water Column
Chu, Peter C.
1 1 Three-Dimensional Hydrodynamic Model for Prediction of Falling Cylinder Through Water Column-coordinate), cylinder's main-axis following coordinate (M-coordinate), and hydrodynamic force following coordinate (F-coordinate system. The hydrodynamic forces (such as the drag and lift forces) and their moments are easily computed
Rapid three-dimensional manufacturing of microfluidic structures using a scanning laser system
Rapid three-dimensional manufacturing of microfluidic structures using a scanning laser system Biao-dimensional manufacturing approach to the rapid processing of microfluidic structures using a scanning laser system. The scanning laser manufacturing technique could be potentially applied to a wide range of materials,10
Three-dimensional turbulent swirling flow in a cylinder: Experiments and computations
Gupta, Amit
is cycloning, where particles are separated from a fluid owing to centrifugal forces imparted by a swirling axial. But a few cylin- drical cyclones of the type described here have been used to separate liquid Abstract Dynamics of the three-dimensional flow in a cyclone with tangential inlet and tangential exit were
Three-Dimensional Computational Analysis of Transport Phenomena in a PEM Fuel Cell
Victoria, University of
Three-Dimensional Computational Analysis of Transport Phenomena in a PEM Fuel Cell by Torsten or other means, without permission of the author. #12;Supervisor: Dr. N. Djilali Abstract Fuel cells-isothermal computational model of a proton exchange membrane fuel cell (PEMFC). The model was developed to improve
An Effective Approach for Identifying Evolving Three-Dimensional Structural Motifs in Protein
Yang, Hui
have been employed to study the protein folding process, in which a protein acquires its func- tional three-dimensional structure. This has resulted in a large number of protein folding trajectories of the protein folding mechanism. In this paper, we focus on identifying im- portant 3D structural motifs
Ng, Chung-Sang
Three Dimensional Simulations of the Parker's Model of Solar Coronal Heating: Lundquist Number analysis as well as 2D simulations. In the same limit the average magnetic energy built up by the random by NSF grant AST-0434322, NASA grant NNX08BA71G, and DOE. #12;Parker's model of coronal heating through
RIS-M-2256 INPUT DESCRIPTION FOR THE THREE-DIMENSIONAL
, PWR TYPE REACTORS, REACTOR KINETICS, THREE-DIMENSIONAL CALCULATIONS, TRANSIENTS. UDC 621.039.514 : 621 calculations for the PWR core. It combines a nodal theory neutron kinetics calculation with transient sub calculations. The present report describes the input for ANTI. INIS descriptors; A CODES, BURNUP, HYDRAULICS
An H-Formulation for the Three-Dimensional Eddy Current Problem in Laminated Structures
Zheng, Weiying
An H- Formulation for the Three-Dimensional Eddy Current Problem in Laminated Structures Peijun Li-dimensional eddy currents in grain-oriented (GO) silicon steel laminations since the coating film is only several to the smallest scale can be up to 106. In this paper, we study an H- formulation for the nonlinear eddy current
Jablonowski, Christiane
Three Dimensional Adaptive Mesh Refinement on a Spherical Shell for Atmospheric Models for Atmospheric Research 1. Introduction One of the most important advances needed in global climate models of this project is a parallel adaptive grid library, which is currently under development at the University
THREE-DIMENSIONAL RECONNECTION OF UNTWISTED MAGNETIC FLUX TUBES M. G. Linton1
Priest, Eric
). Reconnection prob- ably plays an important role as an energy source for coronal heating (e.g., Parker 1972 direction. These studies generally focus on the small-scale dynamics in the immediate neighborhood in which these local reconnection regions connect to the larger scale, global, three-dimensional magnetic
Kelley, Kirk Lee
1994-01-01T23:59:59.000Z
The goal of this study is to demonstrate how the use of three-dimensional computer reconstruction of architecture from an archaelogical site can be used to gain a better understanding of the culture represented. To demonstrate this process, a three...
Waveguides in three-dimensional photonic bandgap materials for particle-accelerator on a
Byer, Robert L.
Waveguides in three-dimensional photonic bandgap materials for particle-accelerator on a chip@physics.anu.edu.au Abstract: The quest for less costly and more compact high-energy particle accelerators of suggested concepts, the photonic accelerator design by B. M. Cowan [Phys. Rev. ST Accel. Beams 11, 011301
Liu, Yijun
Adaptive fast multipole boundary element method for three-dimensional half-space acoustic wave: Acoustics 3D half space Fast multipole BEM Windmill models a b s t r a c t A new adaptive fast multipole. This procedure simplifies the implementation of the adaptive fast multipole BEM and reduces the CPU time
Uplift of Beta Regio: Three-dimensional models A. V. Vezolainen and V. S. Solomatov
Solomatov, Slava
Uplift of Beta Regio: Three-dimensional models A. V. Vezolainen and V. S. Solomatov Department of Beta Regio caused by a mantle plume satisfy constraints on gravity, topography, rheology, and the uplift rate substantially better than two-dimensional models. In particular, the uplift time of Beta
A Three-Dimensional Geographic and Storm Surge Data Integration System for Evacuation Planning
Chen, Shu-Ching
@fiu.edu Abstract The rise of offshore water caused by the high winds of a low pressure weather system, or storm to construct a three-dimensional ocean po- sitioned over the terrain models. Ambient details such as wind, vegetation, ocean waves, and traffic are animated based on up-to-date wind and storm surge data. Videos
he edge of a torn plastic sheet forms a complex three-dimensional fractal
Texas at Austin. University of
T he edge of a torn plastic sheet forms a complex three-dimensional fractal shape. We have found to the generation of characteristic wavy shapes. We used rectangular plastic sheets pulled from the sides (in the y produce an irreversible plastic deforma- tion of the sheet and, as they are relieved, the deformed sheet
A numerical model of convective heat transfer in a three dimensional channel with baffles
Lopez Buso, Jorge Ricardo
1995-01-01T23:59:59.000Z
the experimental results of Goldstein and Kreid (1967) and Beavers et. al. (1970) for a three-dimensional laminar flow in a channel without baffles. Parametric runs were made for Reynolds Numbers (Re) of 150, 250, 3 50, and 450, for blockage ratios (H/Dy) of 0. 5...
Nanoscale Strainability of Graphene by Laser Shock-Induced Three-Dimensional Shaping
Chen, Yong P.
Nanoscale Strainability of Graphene by Laser Shock-Induced Three- Dimensional Shaping Ji Li,, Ting, West Lafayette, Indiana 47907, United States ABSTRACT: Graphene has many promising physical properties. It has been discovered that local strain in a graphene sheet can alter its conducting properties
Propagation of three--dimensional Alfv'en waves in a stratified, thermally conducting solar wind
Propagation of three--dimensional Alfv'en waves in a stratified, thermally conducting solar wind S to the well--known thermal expansion of the solar corona [Parker, 1958, 1963, 1991]. In particular Alfv'en waves in the solar atmosphere and wind, taking into account relevant physical effects
Trikania, Andra
1996-01-01T23:59:59.000Z
This study reports an investigation of the structure and stratigraphy of the downdip Yegua sandstones at Edna Field, Jackson County, South Texas. The study is based on 22.9 square miles of three dimensional (3-D) seismic data, well-logs from 15...
Self-Organizing Fault-Tolerant Topology Control in Large-Scale Three-Dimensional
Wang, Yu
be deployed in three-dimensional (3D) space, such as under water wireless sensor networks in ocean or mobile to investigate self-organizing fault-tolerant topology control protocols for large- scale 3D wireless networks networks. Our simulation confirms our theoretical proofs for all proposed 3D topologies. Categories
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. ???, NO. , PAGES 125, Three Dimensional Coronal Density
California at Berkeley, University of
the dominance of magnetic forces in most of the corona, recent studies show that plasma beta in the core Abstract. The three-dimensional density structure of the solar corona is a fundamental boundary condition dependence of the neutral lines implicit beneath the streamer cores. Nonradiality of streamers and solar B
Three-Dimensional Simulations of Liquid Feed Direct Methanol Wenpeng Liu*,a
Three-Dimensional Simulations of Liquid Feed Direct Methanol Fuel Cells Wenpeng Liu*,a and Chao that performance and design of a liquid feed direct methanol fuel cell DMFC is controlled not only by electrochemical kinetics and methanol crossover but also by water transport and by their complex interactions
Jesus, Sérgio M.
Classification of Cabo Frio (Brazil) three-dimensional ocean features using single-slice acoustic-000 Arraial do Cabo, RJ, Brazil, {lcalado, ana.claudia}@ieapm.mar.mil.br Acoustic tomography is now a well for an instantaneous sound speed field constructed from dynamical predictions for Cabo Frio, Brazil. The results show
GEOPHYSICAL RESEARCH LETTERS, VOL. , NO. , PAGES 14, Three-dimensional energetic ion sounding of the
,4 Abstract. We present new results using energetic parti- cles to remotely sound the highGEOPHYSICAL RESEARCH LETTERS, VOL. , NO. , PAGES 14, Three-dimensional energetic ion sounding present a new technique to remotely sense the magnetopause in three dimensions as a function of time
Three Dimensional Graphics Algorithms on the MicroGrain Array ProcessorII
Bishop, Benjamin
Three Dimensional Graphics Algorithms on the MicroÂGrain Array ProcessorÂII Benjamin Bishop Yan The Pennsylvania State University University Park, PA 16802 Abstract ThreeÂdimensional graphics processors play tools, architectural CAD tools, and physical modeling. But high perÂ formance graphics subsystems
Ecology Letters, (2003) 6: 13-18 Are three-dimensional spider webs defensive
Mathis, Wayne N.
2003-01-01T23:59:59.000Z
LETTER Ecology Letters, (2003) 6: 13-18 Are three-dimensional spider webs defensive adaptations? Abstract Spider webs result from complex behaviours that have evolved under many selective pressures. Webs risk in the evolution of web architecture. The ecological success of spiders has been attributed to key
Wong, Kenneth K.Y.
ForReview Only Quantification of Mitral Valve Morphology with Three- dimensional Echocardiography. of Medicine & Therapeutics Keywords: mitral valve, echocardiography, imaging Category: Diagnostic imaging/Nuclear medicine Japanese Circulation Society Circulation Journal #12;ForReview Only Quantification of Mitral Valve
Using Real-Time Three-Dimensional Ultrasound to Characterize Mitral Valve Motion
Ayache, Nicholas
Using Real-Time Three-Dimensional Ultrasound to Characterize Mitral Valve Motion Paul M. Novotnya results aim to fully characterize the four-dimensional (3D + time) movement of the mitral valve for better understanding of its behavior prior to surgical interventions, such as mitral valve repair. A behavior model
Salvaggio, Carl
. These routines require a sequence of images to evaluate tracking algorithms. The evaluation of sensor performanceTHREE-DIMENSIONAL LONGWAVE INFRARED (LWIR) SYNTHETIC IMAGE GENERATION INCORPORATING ANGULAR Memorial Drive Rochester, New York 14623-0887 ABSTRAO A technique for longwave infrared (LWIR) synthetic
Optics & Laser Technology 40 (2008) 625631 Three-dimensional non-destructive optical evaluation
Chen, Zhongping
2008-01-01T23:59:59.000Z
. A pyrometer, an infrared radiation sensor, is used to monitor surface temperature variation in laser brazingOptics & Laser Technology 40 (2008) 625631 Three-dimensional non-destructive optical evaluation of laser-processing performance using optical coherence tomography Youngseop Kima , Eun Seo Choia
Texas at Arlington, University of
18TH INTERNATIONAL CONFERENCE ON COMPOSITE MATERIALS Abstract Accurate three-dimensional stress for materials with highly anisotropic mechanical properties. Among such materials, glass-fiber and carbon properties for composite materials, and that can enable a major shift toward accurate 3D material
A novel three-dimensional model to quantify metastatic melanoma invasion
George, Steven C.
A novel three-dimensional model to quantify metastatic melanoma invasion Cyrus M. Ghajar,1 Vinod. Culturing melanomas of different meta- static capacities within the system showed that each cell type (i.e., matrix components, interstitial cell presence) on planar and vertical melanoma invasion. We
Cao, Guozhong
Three-Dimensional Coherent Titania-Mesoporous Carbon Nanocomposite and Its Lithium-Ion Storage Properties Laifa Shen,, Evan Uchaker, Changzhou Yuan, Ping Nie, Ming Zhang, Xiaogang Zhang,*, and Guozhong into the channels of surface- oxidized mesoporous carbon (CMK-3) by means of electrostatic interaction, followed
The Effects of Three-Dimensional Canopy Management on Overseeded Warm-Season Fairway Turf
as a sustainable warm-season turfgrass but a lack of cultural management data has hindered its acceptance. FineThe Effects of Three-Dimensional Canopy Management on Overseeded Warm-Season Fairway Turf Scientist: Kurt Steinke, Department of Soil and Crop Sciences Funding: $7,000 The objectives are to 1) discover
Review and Projections of Integrated Cooling Systems for Three-Dimensional
Kandlikar, Satish
Review and Projections of Integrated Cooling Systems for Three-Dimensional Integrated Circuits and integrated cooling systems. For heat fluxes of 50100 W/cm2 on each side of a chip in a 3D IC package outstanding issues in the cooling system design were outlined. Before reviewing available literature
Predicting Three-Dimensional Structures of Transmembrane Domains of -Barrel Membrane Proteins
Dai, Yang
for -barrel membrane proteins, and the lack of an overall quantitative theoretical understandingPredicting Three-Dimensional Structures of Transmembrane Domains of -Barrel Membrane Proteins Information ABSTRACT: -Barrel membrane proteins are found in the outer membrane of gram-negative bacteria
Small divisor problem in the theory of three-dimensional water gravity waves
Iooss, GÃ©rard
Small divisor problem in the theory of three-dimensional water gravity waves GÂ´erard Iooss , Pavel of Sciences, Lavryentyev pr. 15, Novosibirsk 630090, Russia gerard.iooss@inln.cnrs.fr, plotnikov@hydro of small divisors, the main difficulty is the inversion of the linearized operator at a non trivial point
Three-dimensional Reconstruction of Agrobacterium VirE2 Protein with Single-stranded DNA*
Citovsky, Vitaly
for publication, February 18, 2004, and in revised form, March 29, 2004 Published, JBC Papers in Press, March 30 ("telephone coil") organization of the VirE2- DNA complex. Here we report a three-dimensional re- construction breeding (1618). Upon induction of the vir region by detection of plant-specific wound signals, the VirD1
PARTICLE ACCELERATION IN A THREE-DIMENSIONAL MODEL OF RECONNECTING CORONAL MAGNETIC FIELDS
Isliker, Heinz
PARTICLE ACCELERATION IN A THREE-DIMENSIONAL MODEL OF RECONNECTING CORONAL MAGNETIC FIELDS PETER J in final form 18 October 2005) Abstract. Particle acceleration in large-scale turbulent coronal magnetic to be addressed, such as feedback between particle acceleration and MHD, are discussed. Keywords: particle
Direct three-dimensional visualization of membrane disruption by amyloid fibrils
Jelinek, Raz
Direct three-dimensional visualization of membrane disruption by amyloid fibrils Lilia Milanesia damage by specific interactions of a lipid bilayer with amyloid-like fibrils formed in vitro from 2-microglobulin (2m). Using cryoelectron tomography, we demonstrate that frag- mented 2m amyloid fibrils interact
Two-and three-dimensional folding of thin film single-crystalline silicon for photovoltaic
Lewis, Jennifer
Two- and three-dimensional folding of thin film single-crystalline silicon for photovoltaic power of a functional, nonpla- nar photovoltaic (PV) device. A mechanics model based on the theory of thin plates self-folding photovoltaics capillary force Silicon, in crystalline and amorphous forms, is currently
Computations of Three-Dimensional Overturning Waves in Shallow Water: Dynamics and Kinematics
Grilli, StÃ©phan T.
Computations of Three-Dimensional Overturning Waves in Shallow Water: Dynamics and Kinematics P. A detailed analysis of wave profiles and wave kinematics (both on the free surface and within the flow waves over constant depth, greatly contributed to our understandingof breakingwave kinemat- ics
Fast three-dimensional terahertz computed tomography using real-time line projection of
Paris-Sud XI, Université de
Fast three-dimensional terahertz computed tomography using real-time line projection of intense terahertz computed tomography by using real-time line projection of intense terahertz beam generated). 4. B. Ferguson, S. Wang, D. Gray, D. Abbot, and X.-C. Zhang, "T-ray computed tomography," Opt. Lett
Brown, Michael R.
Three-dimensional MHD simulations of counter-helicity spheromak merging in the Swarthmore Spheromak September 2011) Recent counter-helicity spheromak merging experiments in the Swarthmore Spheromak Experiment spheromak- and FRC-like characteristics. In this paper, the SSX merging process is studied in detail using
Review of Three-Dimensional Holographic Imaging by Fresnel Incoherent Correlation Holograms
Rosen, Joseph
010103-1 Review of Three-Dimensional Holographic Imaging by Fresnel Incoherent Correlation our recently proposed single-channel optical system for generating digital Fresnel holograms of 3-D of spherical beams creates the Fresnel hologram of the observed 3-D object. When this hologram is reconstructed
Rosen, Joseph
Fourier, Fresnel and Image CGHs of three-dimensional objects observed from many different of synthesizing three types of computer-generated hologram (CGH); Fourier, Fresnel and image CGHs. These holograms in the computer as a Fourier hologram. Then, it can be converted to either Fresnel or image holograms by computing
Exact sequence analysis for three-dimensional hydrophobic-polar lattice proteins
Janke, Wolfhard
Exact sequence analysis for three-dimensional hydrophobic-polar lattice proteins Reinhard Schiemann 17 March 2005 We have exactly enumerated all sequences and conformations of hydrophobic-polar HP sequences, i.e., sequences that have a nondegenerate ground state. Furthermore we were interested
Three-dimensional deformation caused by the Bam, Iran, earthquake and the
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 Â¼ 6.5 Bam earthquake in Iran determined using the SAR data from the ERS
The role of three-dimensional morphology on the efficiency of hybrid polymer solar cells
Schmidt, Volker
1 The role of three-dimensional morphology on the efficiency of hybrid polymer solar cells Stefan D.a.j.janssen@tue.nl #12;2 Abstract: The efficiency of polymer solar cells critically depends on the intimacy of mixing and quantitative correlation between solar cell performance, photophysical data and the three
Apical polarity in three-dimensional culture systems: where to now?
Inman, J.L.; Bissell, Mina
2010-01-21T23:59:59.000Z
Delineation of the mechanisms that establish and maintain the polarity of epithelial tissues is essential to understanding morphogenesis, tissue specificity and cancer. Three-dimensional culture assays provide a useful platform for dissecting these processes but, as discussed in a recent study in BMC Biology on the culture of mammary gland epithelial cells, multiple parameters that influence the model must be taken into account.
A Three-Dimensional Computational Model of PEM Fuel Cell with Serpentine Gas Channels
Victoria, University of
A Three-Dimensional Computational Model of PEM Fuel Cell with Serpentine Gas Channels by Phong) fuel cell with serpentine gas flow channels is presented in this thesis. This comprehensive model accounts for important transport phenomena in a fuel cell such as heat transfer, mass transfer, electrode
THREE-DIMENSIONAL LUNG DENSITOMETER USING CdTe DETECTORS FOR DIAGNOSIS AND
Paris-Sud XI, Université de
369 THREE-DIMENSIONAL LUNG DENSITOMETER USING CdTe DETECTORS FOR DIAGNOSIS AND EVALUATION is optimized for lung densitometry, similar configurations can be used for bone densito- metry. - The measurement of absolute lung density by a non-invasive technique is of impor- tance in assessing the status
Three dimensional reconstruction of aerogels from TEM images Florence Despetis1,2
Paris-Sud XI, UniversitÃ© de
Three dimensional reconstruction of aerogels from TEM images Florence Despetis1,2 ,Nadjette to compute their physical properties. We focus here on base catalyzed and colloidal silica aerogels, which are fractal materials and we use an original method for the reconstruction of these aerogels from TEM images
Kelley, Kirk Lee
1994-01-01T23:59:59.000Z
The goal of this study is to demonstrate how the use of three-dimensional computer reconstruction of architecture from an archaelogical site can be used to gain a better understanding of the culture represented. To demonstrate this process, a three...
Three Dimensional Simulation of Jet Formation in Collapsing Condensates Weizhu Bao1
Markowich, Peter A.
Three Dimensional Simulation of Jet Formation in Collapsing Condensates Weizhu Bao1 , D. Jaksch2, 2003) We numerically study the behavior of collapsing and exploding condensates using the parameters body loss rate from the number of remnant condensate atoms and collapse times and obtain only one
Towards Printable Robotics: Origami-Inspired Planar Fabrication of Three-Dimensional Mechanisms
Wood, Robert
a fast and low-cost fabrication method to modern, real-world robotic applications. To this end, we employTowards Printable Robotics: Origami-Inspired Planar Fabrication of Three-Dimensional Mechanisms in the way engineers develop robotic hardware with speed and low cost in a straightforward procedure
expense between a one-dimensional (1-D) advection-dispersion model and a fully three-dimensional (3-D-dimensional fractional derivative, and multirate transient storage models Eric J. Anderson1 and Mantha S. Phanikumar2] Large rivers are major conduits for sediment and nutrient transport and play an important role in global
Three dimensional controlled assembly of gold nanoparticles using a micromachined platform
Dokmeci, Mehmet
Three dimensional controlled assembly of gold nanoparticles using a micromachined platform Nishant By using optical lithographic procedures, the authors present a micromachined platform for large scale to vary the height of the 3D platform for meeting different application requirements. This research
A Stochastic Model of Transport in Three-Dimensional Porous Media1
Boyer, Edmond
Lee2 Modeling of solute transport remains a key issue in the area of groundwater contamination transport, non-Fickian dispersion, random walk, stochastic processes. INTRODUCTION Solute transport modelA Stochastic Model of Transport in Three-Dimensional Porous Media1 Cyril Fleurant2 and Jan van der
Borhanian, J. [Department of Physics, Faculty of Science, University of Mohaghegh Ardabili, P. O. Box 179, Ardabil (Iran, Islamic Republic of); Shahmansouri, M. [Department of Physics, Faculty of Science, Arak University, Arak, P.O. Box 38156-8-8349 (Iran, Islamic Republic of)
2013-01-15T23:59:59.000Z
A theoretical investigation is carried out to study the existence and characteristics of propagation of dust-acoustic (DA) waves in an electron-depleted dusty plasma with two-temperature ions, which are modeled by kappa distribution functions. A three-dimensional cylindrical Kadomtsev-Petviashvili equation governing evolution of small but finite amplitude DA waves is derived by means of a reductive perturbation method. The influence of physical parameters on solitary wave structure is examined. Furthermore, the energy integral equation is used to study the existence domains of the localized structures. It is found that the present model can be employed to describe the existence of positive as well as negative polarity DA solitary waves by selecting special values for parameters of the system, e.g., superthermal index of cold and/or hot ions, cold to hot ion density ratio, and hot to cold ion temperature ratio. This model may be useful to understand the excitation of nonlinear DA waves in astrophysical objects.
Experimental Realization of a Three-Dimensional Topological Insulator, Bi 2Te3
Siemons, W.
2010-02-24T23:59:59.000Z
Three-dimensional topological insulators are a new state of quantum matter with a bulk gap and odd number of relativistic Dirac fermions on the surface. By investigating the surface state of Bi{sub 2}Te{sub 3} with angle-resolved photoemission spectroscopy, we demonstrate that the surface state consists of a single nondegenerate Dirac cone. Furthermore, with appropriate hole doping, the Fermi level can be tuned to intersect only the surface states, indicating a full energy gap for the bulk states. Our results establish that Bi{sub 2}Te{sub 3} is a simple model system for the three-dimensional topological insulator with a single Dirac cone on the surface. The large bulk gap of Bi{sub 2}Te{sub 3} also points to promising potential for high-temperature spintronics applications.
CARS polarized microscopy of three-dimensional director structures in liquid crystals
A. V. Kachynski; A. N. Kuzmin; P. N. Prasad; I. I. Smalyukh
2007-10-18T23:59:59.000Z
We demonstrate three-dimensional vibrational imaging of director structures in liquid crystals using coherent anti-Stokes Raman scattering (CARS) polarized microscopy. Spatial mapping of the structures is based on sensitivity of a polarized CARS signal to orientation of anisotropic molecules in liquid crystals. As an example, we study structures in a smectic material and demonstrate that single-scan CARS and two-photon fluorescence images of molecular orientation patterns are consistent with each other and with the structure model.
The ground state energy of the three dimensional Ginzburg-Landau model in the mixed phase
Ayman Kachmar
2010-10-10T23:59:59.000Z
We consider the Ginzburg-Landau functional defined over a bounded and smooth three dimensional domain. Supposing that the strength of the applied magnetic field varies between the first and second critical fields, in such a way that $H_{C_1}\\ll H\\ll H_{C_2}$, we estimate the ground state energy to leading order as the Ginzburg-Landau parameter tends to infinity.
Volume-scalable high-brightness three-dimensional visible light source
Subramania, Ganapathi; Fischer, Arthur J; Wang, George T; Li, Qiming
2014-02-18T23:59:59.000Z
A volume-scalable, high-brightness, electrically driven visible light source comprises a three-dimensional photonic crystal (3DPC) comprising one or more direct bandgap semiconductors. The improved light emission performance of the invention is achieved based on the enhancement of radiative emission of light emitters placed inside a 3DPC due to the strong modification of the photonic density-of-states engendered by the 3DPC.
Perception of Three-Dimensional Shape from Structure-from-Motion (SFM) Stimuli in Infancy
Hirshkowitz, Amy
2012-07-16T23:59:59.000Z
presentations were controlled by an experimenter behind a curtain from a Dell Precision M6400 laptop computer with a Windows XP operating system. The Tobii T60 XL monitor was set to 32-bit color and screen size to 12 1024 x 768 pixels. A Logitech Webcam Pro... of the requirements for the degree of MASTER OF SCIENCE May 2012 Major Subject: Psychology Perception of Three-Dimensional Shape from Structure-from-Motion (SFM) Stimuli in Infancy Copyright 2012 Amy Hirshkowitz...
Three dimensional simulation of the microstructure development in Ni-20%Fe nanocrystalline deposits
Li, H.; Czerwinski, F.; Szpunar, J.A. [McGill Univ., Montreal, Quebec (Canada). Dept. of Metallurgical Engineering
1997-09-01T23:59:59.000Z
A Monte-Carlo computer model was applied to simulate a development of the three dimensional microstructure during electrodeposition of nanocrystalline alloys. The driving force for this process was the minimization of free energy of the system. For a particular deposit of Ni-20%Fe, the influence of the overpotential and current density on the grain size was tested. A strong decrease in grain size with increasing overpotential and current density obtained from the simulation is in qualitative agreement with the experimental data.
A three-dimensional model for particle dissolution in binary alloys F.J. Vermolen a,*, E. Javierre a
Vuik, Kees
A three-dimensional model for particle dissolution in binary alloys F.J. Vermolen a,*, E. Javierre, Department of Aerospace Engineering, Kluyverweg 1, 2629 HS Delft, The Netherlands Received 13 September 2006; accepted 20 September 2006 Abstract A three-dimensional model for particle dissolution in binary alloys
Ewing, Richard E.
A ThreeDimensional Finite Element Simulation for Transport of Nuclear Waste Contamination for transport of nuclearwaste contamination in threedimensional porous media are presented with a description of contamination of groundwater by highlevel nuclear waste and a wide variety of other sources makes a proper
Three-dimensional morphology of cementite in steel studied by X-ray phase-contrast tomography
Stallinga, Sjoerd
Three-dimensional morphology of cementite in steel studied by X-ray phase-contrast tomography-destructive, in-line X-ray phase-contrast tomography (PCT) can be used to study the three-dimensional mor- phology- and cold-forming operations of the steel. Studying the evolution of the morphology of cement- ite in 3-D
Robert, Pincus
The Accuracy of Determining Three-Dimensional Radiative Transfer Effects in Cumulus Clouds Using. Three-dimensional radiative transfer effects and why one might estimate them in two-dimensional clouds expensive independent column approximation is called the 3D radiative transfer effect. Assessing
Blue-phase templated fabrication of three-dimensional nanostructures for photonic applications
F. Castles; F. V. Day; S. M. Morris; D. -H. Ko; D. J. Gardiner; M. M. Qasim; S. Nosheen; P. J. W. Hands; S. S. Choi; R. H. Friend; H. J. Coles
2013-10-27T23:59:59.000Z
A promising approach to the fabrication of materials with nanoscale features is the transfer of liquid-crystalline structure to polymers. However, this has not been achieved in systems with full three-dimensional periodicity. Here we demonstrate the fabrication of self-assembled three-dimensional nanostructures by polymer templating blue phase I, a chiral liquid crystal with cubic symmetry. Blue phase I was photopolymerized and the remaining liquid crystal removed to create a porous free-standing cast which retains the chiral three-dimensional structure of the blue phase, yet contains no chiral additive molecules. The cast may in turn be used as a hard template for the fabrication of new materials. By refilling the cast with an achiral nematic liquid crystal, we created templated blue phases which have unprecedented thermal stability in the range -125 to 125 [degrees symbol]C, and that act both as mirrorless lasers and switchable electro-optic devices. Blue-phase templated materials will facilitate advances in device architectures for photonics applications in particular.
Technical Note Variational free energy and the Laplace approximation
Daunizeau, Jean
Technical Note Variational free energy and the Laplace approximation Karl Friston,a, Jérémie October 2006 This note derives the variational free energy under the Laplace approximation, with a focus. This is relevant when using the free energy as an approximation to the log-evidence in Bayesian model averaging
Technical Note Variational free energy and the Laplace approximation
Penny, Will
Technical Note Variational free energy and the Laplace approximation Karl Friston,a, Jérémie the variational free energy under the Laplace approximation, with a focus on accounting for additional model complexity induced by increasing the number of model parameters. This is relevant when using the free energy
A. V. Pavlov-Maxorin
2014-10-19T23:59:59.000Z
In article a new class of the odd ore even transforms of Laplace is presented. The class leads to some unforeseeable consequences in direction of the Fourier transforms.The potential of Newton as one of the form of the double Laplace transform is considered too.
D'Angelo, Gennaro
2013-01-01T23:59:59.000Z
We perform global three-dimensional (3-D) radiation-hydrodynamics calculations of the envelopes surrounding young planetary cores of 5, 10, and 15 Earth masses, located in a protoplanetary disk at 5 and 10 AU from a solar-mass star. We apply a nested-grid technique to resolve the thermodynamics of the disk at the orbital-radius length scale and that of the envelope at the core-radius length scale. The gas is modeled as a solar mixture of molecular and atomic hydrogen, helium, and their ions. The equation of state accounts for both gas and radiation, and gas energy includes contributions from rotational and vibrational states of molecular hydrogen and from ionization of atomic species. Dust opacities are computed from first principles, applying the full Mie theory. One-dimensional (1-D) calculations of planet formation are used to supplement the 3-D calculations by providing energy deposition rates in the envelope due to solids accretion. We compare 1-D and 3-D envelopes and find that masses and gas accretion ...
Hoshino, T.; Shirakawa, T.
1982-03-01T23:59:59.000Z
The three-dimensional boiling water reactor (BWR) core following the daily load was simulated by the use of the processor array for continuum simulation (PACS-32), a newly developed parallel microprocessor system. The PACS system consists of 32 processing units (PUs) (microprocessors) and has a multiinstruction, multidata type architecture, being optimum to the numerical simulation of the partial differential equations. The BWR core model includes the modified twogroup finite difference, coarse-mesh model for neutronics, steady-state model for thermohydraulics, criticality control by core coolant flow, and the time-dependent solution of iodine-xenon dynamics with constant flux level. The analysis of the parallel processing program revealed that the overhead is independent from the number of PUs and that the efficiency of PUs, i.e., the ratio of effective calculation over total, amounts to 75%, even up to 90% if it is limited to the core part. Simulation was made on the daily load follow for 144 h including the weekend, which took 1.3 central processing unit hours by the PACS system. The PACS system demonstrated a computation speed nearly one-tenth that of the large-scale high-speed general purpose computer, with a 25 times better cost performance ratio and showed that the system could be used as the pratical BWR core simulator with more complicated core models.
Simulations of Failure via Three-Dimensional Cracking in Fuel Cladding for Advanced Nuclear Fuels
Lu, Hongbing; Bukkapatnam, Satish; Harimkar, Sandip; Singh, Raman; Bardenhagen, Scott
2014-01-09T23:59:59.000Z
Enhancing performance of fuel cladding and duct alloys is a key means of increasing fuel burnup. This project will address the failure of fuel cladding via three-dimensional cracking models. Researchers will develop a simulation code for the failure of the fuel cladding and validate the code through experiments. The objective is to develop an algorithm to determine the failure of fuel cladding in the form of three-dimensional cracking due to prolonged exposure under varying conditions of pressure, temperature, chemical environment, and irradiation. This project encompasses the following tasks: 1. Simulate 3D crack initiation and growth under instantaneous and/or fatigue loads using a new variant of the material point method (MPM); 2. Simulate debonding of the materials in the crack path using cohesive elements, considering normal and shear traction separation laws; 3. Determine the crack propagation path, considering damage of the materials incorporated in the cohesive elements to allow the energy release rate to be minimized; 4. Simulate the three-dimensional fatigue crack growth as a function of loading histories; 5. Verify the simulation code by comparing results to theoretical and numerical studies available in the literature; 6. Conduct experiments to observe the crack path and surface profile in unused fuel cladding and validate against simulation results; and 7. Expand the adaptive mesh refinement infrastructure parallel processing environment to allow adaptive mesh refinement at the 3D crack fronts and adaptive mesh merging in the wake of cracks. Fuel cladding is made of materials such as stainless steels and ferritic steels with added alloying elements, which increase stability and durability under irradiation. As fuel cladding is subjected to water, chemicals, fission gas, pressure, high temperatures, and irradiation while in service, understanding performance is essential. In the fast fuel used in advanced burner reactors, simulations of the nuclear fuels are critical to understand the burnup, and thus the fuel efficiency.
Development of a transient three-dimensional neutron transport code with feedback
Waddell, M.W. Jr.
1994-07-19T23:59:59.000Z
A new code is being developed at the Y-12 Plant for solving the time-dependent, three-dimensional Boltzmann transport model with feedback. The new code, PADK, uses the quasi-static method in its adiabatic form and is to be utilized to analyze hypothetical criticality accidents. A description of the code along with preliminary results without feedback are presented in this paper. The code is applied to 2 standard benchmark problems and the results are compared to another method. Also, the code is used to model the GODIVA reactor. Further work needed to be completed is described.
Correlation buildup during recrystallization in three-dimensional dusty plasma clusters
Schella, André; Mulsow, Matthias; Melzer, André [Institut für Physik, Ernst-Moritz-Arndt-Universität Greifswald, 17489 Greifswald (Germany)] [Institut für Physik, Ernst-Moritz-Arndt-Universität Greifswald, 17489 Greifswald (Germany)
2014-05-15T23:59:59.000Z
The recrystallization process of finite three-dimensional dust clouds after laser heating is studied experimentally. The time-dependent Coulomb coupling parameter is presented, showing that the recrystallization starts with an exponential cooling phase where cooling is slower than damping by the neutral gas friction. At later times, the coupling parameter oscillates into equilibrium. It is found that a large fraction of cluster states after recrystallization experiments is in metastable states. The temporal evolution of the correlation buildup shows that correlation occurs on even slower time scale than cooling.
Ridouane, E. H.; Bianchi, M.
2011-11-01T23:59:59.000Z
This study describes a detailed three-dimensional computational fluid dynamics modeling to evaluate the thermal performance of uninsulated wall assemblies accounting for conduction through framing, convection, and radiation. The model allows for material properties variations with temperature. Parameters that were varied in the study include ambient outdoor temperature and cavity surface emissivity. Understanding the thermal performance of uninsulated wall cavities is essential for accurate prediction of energy use in residential buildings. The results can serve as input for building energy simulation tools for modeling the temperature dependent energy performance of homes with uninsulated walls.
Three-Dimensional Momentum Imaging of Electron Wave Packet Interference in Few-Cycle Laser Pulses
Gopal, R.; Simeonidis, K.; Moshammer, R.; Ergler, Th.; Duerr, M.; Kurka, M.; Kuehnel, K.-U.; Tschuch, S.; Schroeter, C.-D.; Bauer, D.; Ullrich, J.; Rudenko, A.; Herrwerth, O.; Uphues, Th.; Schultze, M.; Goulielmakis, E.; Uiberacker, M.; Lezius, M.; Kling, M. F. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Max-Planck Advanced Study Group at CFEL, D-22607 Hamburg (Germany); Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching (Germany)
2009-07-31T23:59:59.000Z
Using a reaction microscope, three-dimensional (3D) electron (and ion) momentum (P) spectra have been recorded for carrier-envelope-phase (CEP) stabilized few-cycle (approx5 fs), intense (approx4x10{sup 14} W/cm{sup 2}) laser pulses (740 nm) impinging on He. Preferential emission of low-energy electrons (E{sub e}<15 eV) to either hemisphere is observed as a function of the CEP. Clear interference patterns emerge in P space at CEPs with maximum asymmetry, interpreted as attosecond interferences of rescattered and directly emitted electron wave packets by means of a simple model.
Coleman-Weinberg mechanism in a three-dimensional supersymmetric Chern-Simons-matter model
Ferrari, A. F. [Centro de Ciencias Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adelia, 166, 09210-170, Santo Andre, SP (Brazil); Gallegos, E. A.; Gomes, M.; Silva, A. J. da [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05315-970, Sao Paulo, SP (Brazil); Lehum, A. C. [Escola de Ciencias e Tecnologia, Universidade Federal do Rio Grande do Norte, Caixa Postal 1524, 59072-970, Natal, RN (Brazil); Nascimento, J. R.; Petrov, A. Yu. [Departamento de Fisica, Universidade Federal da Paraiba, Caixa Postal 5008, 58051-970, Joao Pessoa, Paraiba (Brazil)
2010-07-15T23:59:59.000Z
Using the superfield formalism, we study the dynamical breaking of gauge symmetry and superconformal invariance in the N=1 three-dimensional supersymmetric Chern-Simons model, coupled to a complex scalar superfield with a quartic self-coupling. This is an analogue of the conformally invariant Coleman-Weinberg model in four spacetime dimensions. We show that a mass for the gauge and matter superfields are dynamically generated after two-loop corrections to the effective superpotential. We also discuss the N=2 extension of our work, showing that the Coleman-Weinberg mechanism in such model is not feasible, because it is incompatible with perturbation theory.
Electromagnetic three-dimensional reconstruction of targets from free space experimental data
Geffrin, J.-M.; Chaumet, P. C.; Eyraud, C.; Belkebir, K.; Sabouroux, P. [Aix-Marseille Universite, Ecole Centrale Marseille, and CNRS, Institut Fresnel, Domaine Universitaire de St Jerome, 13013 Marseille (France)
2008-05-12T23:59:59.000Z
This paper deals with the problem of reconstructing the relative permittivity of three-dimensional targets using experimental scattered fields. The fields concerned were measured in an anechoic chamber on the surface of a sphere surrounding the target. The inverse scattering problem is reformulated as an optimization problem that is iteratively solved thanks to a conjugate gradient method and by using the coupled dipoles method as a forward problem solver. The measurement technique and the inversion procedure are briefly described with the inversion results. This work demonstrates the reliability of the experiments and the efficiency of the proposed inverse scattering scheme.
All-dielectric three-dimensional broadband Eaton lens with large refractive index range
Yin, Ming; Yong Tian, Xiao, E-mail: leoxyt@mail.xjtu.edu.cn; Ling Wu, Ling; Chen Li, Di [State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710049 (China)
2014-03-03T23:59:59.000Z
We proposed a method to realize three-dimensional (3D) gradient index (GRIN) devices requiring large refractive index (RI) range with broadband performance. By combining non-resonant GRIN woodpile photonic crystals structure in the metamaterial regime with a compound liquid medium, a wide RI range (1–6.32) was fulfilled flexibly. As a proof-of-principle for the low-loss and non-dispersive method, a 3D Eaton lens was designed and fabricated based on 3D printing process. Full-wave simulation and experiment validated its omnidirectional wave bending effects in a broad bandwidth covering Ku band (12?GHz–18?GHz)
Porosity in millimeter-scale welds of stainless steel : three-dimensional characterization.
Aagesen, Larry K. (University of Michigan, Ann Arbor, MI); Madison, Jonathan D.
2012-05-01T23:59:59.000Z
A variety of edge joints utilizing a continuous wave Nd:YAG laser have been produced and examined in a 304-L stainless steel to advance fundamental understanding of the linkage between processing and resultant microstructure in high-rate solidification events. Acquisition of three-dimensional reconstructions via micro-computed tomography combined with traditional metallography has allowed for qualitative and quantitative characterization of weld joints in a material system of wide use and broad applicability. The presence, variability and distribution of porosity, has been examined for average values, spatial distributions and morphology and then related back to fundamental processing parameters such as weld speed, weld power and laser focal length.
Direct Observations of Three Dimensional Growth of Hydrates Hosted in Porous Media
Kerkar, P.; Jones, K; Kleinberg, R; Lindquist, W; Tomov, S; Feng, H; Mahajan, D
2009-01-01T23:59:59.000Z
The visualization of time-resolved three-dimensional growth of tetrahydrofuran hydrates with glass spheres of uniform size as porous media using synchrotron x-ray computed microtomography is presented. The images of hydrate patches, formed from excess tetrahydrofuran in aqueous solution, show random nucleation and growth concomitant with grain movement but independent of container-wall effect. Away from grain surfaces, hydrate surface curvature was convex showing that liquid, not hydrate, was the wetting phase, similar to ice growth in porous media. The extension of the observed behavior to methane hydrates could have implications in understanding their role in seafloor stability and climate change.
Three-dimensional computer modeling of particulate flow around dust monitors
Nichols, B.D.; Gregory, W.S.
1987-01-01T23:59:59.000Z
SOLA-DM is a three-dimensional finite-difference computer code designed to model the dynamics of an incompressible fluid and the transport of discrete particulate material around obstacles impervious to flow. The numerical methods used in this code are described. SOLA-DM was used to predict the particle flux sampled by the 10-mm Dorr-Oliver Cyclone and MINIRAM dust monitors. Various geometric and dynamic variations of monitor and airflow combinations were tested. The code predictions are shown in computer-generated graphic plots.
Label-free three-dimensional imaging of cell nucleus using third-harmonic generation microscopy
Lin, Jian; Zheng, Wei; Wang, Zi; Huang, Zhiwei, E-mail: biehzw@nus.edu.sg [Optical Bioimaging Laboratory, Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore 117576 (Singapore)
2014-09-08T23:59:59.000Z
We report the implementation of the combined third-harmonic generation (THG) and two-photon excited fluorescence (TPEF) microscopy for label-free three-dimensional (3-D) imaging of cell nucleus morphological changes in liver tissue. THG imaging shows regular spherical shapes of normal hepatocytes nuclei with inner chromatin structures while revealing the condensation of chromatins and nuclear fragmentations in hepatocytes of diseased liver tissue. Colocalized THG and TPEF imaging provides complementary information of cell nuclei and cytoplasm in tissue. This work suggests that 3-D THG microscopy has the potential for quantitative analysis of nuclear morphology in cells at a submicron-resolution without the need for DNA staining.
Progress in Three-Dimensional Coherent X-Ray Diffraction Imaging
Marchesini, S; Chapman, H N; Barty, A; Howells, M R; Cui, C; Spence, J H; Weierstall, U; Noy, A; Hau-Riege, S P; Kinney, J M; Shapiro, D; Beetz, T; Jacobsen, C; Lima, E; Minor, A M; He, H
2005-09-30T23:59:59.000Z
The Fourier inversion of phased coherent diffraction patterns offers images without the resolution and depth-of-focus limitations of lens-based tomographic systems. We report on our recent experimental images inverted using recent developments in phase retrieval algorithms, and summarize efforts that led to these accomplishments. These include ab-initio reconstruction of a two-dimensional test pattern, infinite depth of focus image of a thick object, and its high-resolution ({approx}10 nm resolution) three-dimensional image. Developments on the structural imaging of low density aerogel samples are discussed.
Real-time, interactive animation of deformable two- and three-dimensional objects
Desbrun, Mathieu; Schroeder, Peter; Meyer, Mark; Barr, Alan H.
2003-06-03T23:59:59.000Z
A method of updating in real-time the locations and velocities of mass points of a two- or three-dimensional object represented by a mass-spring system. A modified implicit Euler integration scheme is employed to determine the updated locations and velocities. In an optional post-integration step, the updated locations are corrected to preserve angular momentum. A processor readable medium and a network server each tangibly embodying the method are also provided. A system comprising a processor in combination with the medium, and a system comprising the server in combination with a client for accessing the server over a computer network, are also provided.
Dirk Veestraeten
2015-05-21T23:59:59.000Z
The Laplace transforms of the transition probability density and distribution functions for the Ornstein-Uhlenbeck process contain the product of two parabolic cylinder functions, namely D_{v}(x)D_{v}(y) and D_{v}(x)D_{v-1}(y), respectively. The inverse transforms of these products have as yet not been documented. However, the transition density and distribution functions can be obtained by alternatively applying Doob's transform to the Kolmogorov equation and casting the problem in terms of Brownian motion. Linking the resulting transition density and distribution functions to their Laplace transforms then specifies the inverse transforms to the aforementioned products of parabolic cylinder functions. These two results, the recurrence relation of the parabolic cylinder function and the properties of the Laplace transform then enable the calculation of inverse transforms also for countless other combinations in the orders of the parabolic cylinder functions such as D_{v}(x)D_{v-2}(y), D_{v+1}(x)D_{v-1}(y) and D_{v}(x)D_{v-3}(y).
Bounds on strong field magneto-transport in three-dimensional composites
Marc Briane; Graeme W. Milton
2011-05-19T23:59:59.000Z
This paper deals with bounds satisfied by the effective non-symmetric conductivity of three-dimensional composites in the presence of a strong magnetic field. On the one hand, it is shown that for general composites the antisymmetric part of the effective conductivity cannot be bounded solely in terms of the antisymmetric part of the local conductivity, contrary to the columnar case. So, a suitable rank-two laminate the conductivity of which has a bounded antisymmetric part together with a high-contrast symmetric part, may generate an arbitrarily large antisymmetric part of the effective conductivity. On the other hand, bounds are provided which show that the antisymmetric part of the effective conductivity must go to zero if the upper bound on the antisymmetric part of the local conductivity goes to zero, and the symmetric part of the local conductivity remains bounded below and above. Elementary bounds on the effective moduli are derived assuming the local conductivity and effective conductivity have transverse isotropy in the plane orthogonal to the magnetic field. New Hashin-Shtrikman type bounds for two-phase three-dimensional composites with a non-symmetric conductivity are provided under geometric isotropy of the microstructure. The derivation of the bounds is based on a particular variational principle symmetrizing the problem, and the use of Y-tensors involving the averages of the fields in each phase.
Fully Three-dimensional Simulation and Modeling of a Dense Plasma Focus
Meehan, B T
2014-01-01T23:59:59.000Z
A Dense Plasma Focus (DPF) is a pulsed-power machine that electromagnetically accelerates and cylindrically compresses a shocked plasma in a Z-pinch. The pinch results in a brief (about 100 nanosecond) pulse of X-rays, and, for some working gases, also a pulse of neutrons. A great deal of experimental research has been done into the physics of DPF reactions, and there exist mathematical models describing its behavior during the different time phases of the reaction. Two of the phases, known as the inverse pinch and the rundown, are approximately governed by magnetohydrodynamics, and there are a number of well-established codes for simulating these phases in two dimensions or in three dimensions under the assumption of axial symmetry. There has been little success, however, in developing fully three-dimensional simulations. In this work we present three-dimensional simulations of DPF reactions and demonstrate that 3D simulations predict qualitatively and quantitatively different behavior than their 2D counterp...
Image system for three dimensional, 360 DEGREE, time sequence surface mapping of moving objects
Lu, Shin-Yee (Pleasanton, CA)
1998-01-01T23:59:59.000Z
A three-dimensional motion camera system comprises a light projector placed between two synchronous video cameras all focused on an object-of-interest. The light projector shines a sharp pattern of vertical lines (Ronchi ruling) on the object-of-interest that appear to be bent differently to each camera by virtue of the surface shape of the object-of-interest and the relative geometry of the cameras, light projector and object-of-interest Each video frame is captured in a computer memory and analyzed. Since the relative geometry is known and the system pre-calibrated, the unknown three-dimensional shape of the object-of-interest can be solved for by matching the intersections of the projected light lines with orthogonal epipolar lines corresponding to horizontal rows in the video camera frames. A surface reconstruction is made and displayed on a monitor screen. For 360.degree. all around coverage of theobject-of-interest, two additional sets of light projectors and corresponding cameras are distributed about 120.degree. apart from one another.
Image system for three dimensional, 360{degree}, time sequence surface mapping of moving objects
Lu, S.Y.
1998-12-22T23:59:59.000Z
A three-dimensional motion camera system comprises a light projector placed between two synchronous video cameras all focused on an object-of-interest. The light projector shines a sharp pattern of vertical lines (Ronchi ruling) on the object-of-interest that appear to be bent differently to each camera by virtue of the surface shape of the object-of-interest and the relative geometry of the cameras, light projector and object-of-interest. Each video frame is captured in a computer memory and analyzed. Since the relative geometry is known and the system pre-calibrated, the unknown three-dimensional shape of the object-of-interest can be solved for by matching the intersections of the projected light lines with orthogonal epipolar lines corresponding to horizontal rows in the video camera frames. A surface reconstruction is made and displayed on a monitor screen. For 360{degree} all around coverage of the object-of-interest, two additional sets of light projectors and corresponding cameras are distributed about 120{degree} apart from one another. 20 figs.
Protein crystallography: From X-ray diffraction spots to a three dimensional image
Terwilliger, T.C.; Berendzen, J.
1998-02-25T23:59:59.000Z
Proteins are remarkable molecular machines that are essential for life. They can do many things ranging from the precise control of blood clotting to synthesizing complex organic compounds. Pictures of protein molecules are in high demand in biotechnology because they are important for applications such as drug discovery and for engineering enzymes for commercial use. X-ray crystallography is the most common method for determining the three-dimensional structures of protein molecules. When a crystal of a protein is placed in an X-ray beam, scattering of X-rays off the ordered molecules produces a diffraction pattern that can be measured on a position-sensitive CCD or image-plate detector. Protein crystals typically contain thousands of atoms and the diffraction data are generally measured to relatively low resolution. Consequently the direct methods approaches generally cannot be applied. Instead, if the crystal is modified by adding metal atoms at specific sites or by tuning the wavelength of the X-rays to cross an absorption edge of a metal atom in the crystal, then the information from these additional measurements is sufficient to first identify the /locations of the metal atoms. This information is then used along with the diffraction data to make a three-dimensional picture of electron densities. This picture can be used to determine the position of most or all of the atoms in the protein.
Three-dimensional structure of the flow inside the left ventricle of the human heart
Fortini, S; Espa, S; Cenedese, A
2014-01-01T23:59:59.000Z
The laboratory models of the human heart left ventricle developed in the last decades gave a valuable contribution to the comprehension of the role of the fluid dynamics in the cardiac function and to support the interpretation of the data obtained in vivo. Nevertheless, some questions are still open and new ones stem from the continuous improvements in the diagnostic imaging techniques. Many of these unresolved issues are related to the three-dimensional structure of the left-ventricular flow during the cardiac cycle. In this paper we investigated in detail this aspect using a laboratory model. The ventricle was simulated by a flexible sack varying its volume in time according to a physiologically shaped law. Velocities measured during several cycles on series of parallel planes, taken from two orthogonal points of view, were combined together in order to reconstruct the phase averaged, three-dimensional velocity field. During the diastole, three main steps are recognized in the evolution of the vortical str...
Gribov ambiguity in asymptotically AdS three-dimensional gravity
Anabalon, Andres [Departamento de Ciencias, Facultad de Artes Liberales, Facultad de Ingenieria y Ciencias, Universidad Adolfo Ibanez, Vina Del Mar (Chile); Canfora, Fabrizio [Centro de Estudios Cientificos (CECS), Casilla 1469, Valdivia (Chile); Giacomini, Alex; Oliva, Julio [Instituto de Fisica, Facultad de Ciencias, Universidad Austral de Chile, Valdivia (Chile)
2011-03-15T23:59:59.000Z
In this paper the zero modes of the de Donder gauge Faddeev-Popov operator for three-dimensional gravity with negative cosmological constant are analyzed. It is found that the AdS{sub 3} vacuum produces (infinitely many) normalizable smooth zero modes of the Faddeev-Popov operator. On the other hand, it is found that the Banados-Teitelboim-Zanelli black hole (including the zero mass black hole) does not generate zero modes. This differs from the usual Gribov problem in QCD where, close to the maximally symmetric vacuum, the Faddeev-Popov determinant is positive definite while 'far enough' from the vacuum it can vanish. This suggests that the zero mass Banados-Teitelboim-Zanelli black hole could be a suitable ground state of three-dimensional gravity with negative cosmological constant. Because of the kinematic origin of this result, it also applies for other covariant gravity theories in three dimensions with AdS{sub 3} as maximally symmetric solution, such as new massive gravity and topologically massive gravity. The relevance of these results for supersymmetry breaking is pointed out.
Element-based concrete design with three-dimensional finite element models
O'Leary, M.; Huberty, K.; Winch, S. [Nuclear Power Technologies Div., Sargent and Lundy, 55 East Monroe, Chicago, IL 60603 (United States)
2012-07-01T23:59:59.000Z
A shell element based design of a typical shear wall using analytical results from a three-dimensional finite element model subjected to a combination of vertical and lateral loads is evaluated. The axial and flexural force resultants from each element for every load combination are used to calculate the required reinforcing for each element. Strength for axial loads (P) and out-of-plane flexure (M) in structural walls is determined according to the same P-M interaction procedures used for columns. After each element has been evaluated, a required reinforcing map for each face of each element in the wall is presented along with a constructible reinforcement pattern enveloping the required reinforcing. In order to determine whether the element-based approach meets the requirements of the section cut approach to design, which is typically employed in manual calculations, the total in-plane moment (M) and total vertical axial force (P) across the entire length of the wall is calculated and the P-M points are plotted on an in-plane P-M interaction diagram. It is concluded that element-based design for a structural wall ensures that reinforcement is provided where required by the three-dimensional finite element analysis while still providing sufficient reinforcing to satisfy the section cut approach to design. (authors)
Energetics and structural properties of three-dimensional bosonic clusters near threshold
Hanna, G. J.; Blume, D. [Department of Physics and Astronomy, Washington State University, Pullman, Washington 99164-2814 (United States)
2006-12-15T23:59:59.000Z
We treat three-dimensional bosonic clusters with up to N=40 atoms, interacting additively through two-body van der Waals potentials, in the near-threshold regime. Our study includes super-borromean systems with N atoms for which all subsystems are unbound. We determine the energetics and structural properties such as the expectation value of the interparticle distance as a function of the coupling strength. It has been shown that the coupling strength g{sub *}{sup (N)}, for which the N-body system becomes unbound, is bounded by the coupling constant g{sub *}{sup (N-1)}, for which the next smaller system with N-1 atoms becomes unbound, i.e., g{sub *}{sup (N)}{>=}(N-1)g{sub *}{sup (N-1)}/N. By fitting our numerically determined ground-state energies to a simple functional form with three fitting parameters, we determine the relationship between g{sub *}{sup (N)} and g{sub *}{sup (N-1)}. Our trimer and tetramer energies fall on the so-called Tjon line, which has been studied in nuclear physics. We confirm the existence of generalized Tjon lines for larger clusters. Signatures of the universal behavior of weakly bound three-dimensional clusters can possibly be observed in ultracold Bose gases.
Griggs, D. P.
1981-01-01T23:59:59.000Z
The development of a three-dimensional coupled neutronics/thermalhydraulics code for LWR safety analysis has been initiated. The transient neutronics code QUANDRY has been joined to the two-fluid thermal-hydraulics code ...
Lee, Howon
The rapid manufacture of complex three-dimensional micro-scale components has eluded researchers for decades. Several additive manufacturing options have been limited by either speed or the ability to fabricate true ...
Gong, Nan-Wei
We describe the design and implementation of a dense, low-power wireless sensor network for fine-grained three-dimensional thermal characterization of a large open indoor space. To better understand the airflow dynamics ...
2006-01-01T23:59:59.000Z
I: data acquisition pipeline The electronic version of thiswe describe an integrated pipeline of methods for studyingA three-dimensional analysis pipeline To be able to analyze
Swigler, David Townley
2010-10-12T23:59:59.000Z
A laboratory experiment was performed to investigate the three-dimensional turbulence and kinematic properties that develop due to a breaking solitary and an irregular shallow water bathymetry. A large basin equipped with a piston-type wavemaker...
Hill, Samuel L. (Samuel Lincoln), 1978-
2004-01-01T23:59:59.000Z
The number of three-dimensional displays available is escalating and yet the capturing devices for multiple view content are focused on either single camera precision rigs that are limited to stationary objects or the use ...
Exact Vacuum Solutions to the Einstein Equation
Ying-Qiu Gu
2007-06-17T23:59:59.000Z
In this paper, we present a framework for getting a series of exact vacuum solutions to the Einstein equation. This procedure of resolution is based on a canonical form of the metric. According to this procedure, the Einstein equation can be reduced to some 2-dimensional Laplace-like equations or rotation and divergence equations, which are much convenient for the resolution.
Biffle, J.H.
1993-02-01T23:59:59.000Z
JAC3D is a three-dimensional finite element program designed to solve quasi-static nonlinear mechanics problems. A set of continuum equations describes the nonlinear mechanics involving large rotation and strain. A nonlinear conjugate gradient method is used to solve the equation. The method is implemented in a three-dimensional setting with various methods for accelerating convergence. Sliding interface logic is also implemented. An eight-node Lagrangian uniform strain element is used with hourglass stiffness to control the zero-energy modes. This report documents the elastic and isothermal elastic-plastic material model. Other material models, documented elsewhere, are also available. The program is vectorized for efficient performance on Cray computers. Sample problems described are the bending of a thin beam, the rotation of a unit cube, and the pressurization and thermal loading of a hollow sphere.
7. Biharmonic equation The biharmonic equation is the \\square of the Laplace equation",
Trefethen, Nick
.824 kHz Fig. 1: Chladni gures for a square plate The eigenvalues and eigenfunctions of the biharmonic of such a plate. The physicist and astronomer Ernst Chladni (1756{1827) carried out a famous series of ex in various modes. The resulting patterns are known as Chladni gures and some results from an experiment
Current in a three-dimensional periodic tube with unbiased forces
Bao-quan Ai; Liang-gang Liu
2007-09-15T23:59:59.000Z
Transport of a Brownian particle moving along the axis of a three-dimensional asymmetric periodic tube is investigated in the presence of asymmetric unbiased forces. The reduction of the coordinates may involve not only the appearance of entropic barrier but also the effective diffusion coefficient. It is found that in the presence of entropic barrier, the asymmetry of the tube shape and the asymmetry of the unbiased forces are the two ways of inducing a net current. The current is a peaked function of temperature which indicates that the thermal noise may facilitate the transport even in the presence of entropic barrier. There exists an optimized radius at the bottleneck at which the current takes its maximum value. Competition between the two opposite driving factors may induce current reversal.
Takahiro Kudoh; Shantanu Basu; Youichi Ogata; Takashi Yabe
2007-06-19T23:59:59.000Z
We employ the first fully three-dimensional simulation to study the role of magnetic fields and ion-neutral friction in regulating gravitationally-driven fragmentation of molecular clouds. The cores in an initially subcritical cloud develop gradually over an ambipolar diffusion time while the cores in an initially supercritical cloud develop in a dynamical time. The infall speeds on to cores are subsonic in the case of an initially subcritical cloud, while an extended (\\ga 0.1 pc) region of supersonic infall exists in the case of an initially supercritical cloud. These results are consistent with previous two-dimensional simulations. We also found that a snapshot of the relation between density (rho) and the strength of the magnetic field (B) at different spatial points of the cloud coincides with the evolutionary track of an individual core. When the density becomes large, both relations tend to B \\propto \\rho^{0.5}.
Assembling of three-dimensional crystals by large nonequilibrium depletion force
Deng, Hai-Dong; Fu, Zhi-Cheng; Liu, Hai-Ying; Dai, Qiao-Feng; Wu, Li-Jun; Lan, Sheng; Achanta, Venu Gopal
2010-01-01T23:59:59.000Z
We propose and demonstrate a method to achieve large effective Soret coefficient in colloids by suitably mixing two different particles, e.g., silica beads and Fe3O4 nanoparticles. It is shown that the thermophoretic motion of Fe3O4 nanoparticles out of the heating region results in a large nonequlibrium depletion force for silica beads. Consequently, silica beads are driven quickly to the heating region, forming a three-dimensional crystal with few defects and dislocations. The binding of silica beads is so tight that a colloidal photonic crystal can be achieved after the complete evaporation of solvent, water. Thus, for fabrication of defect free colloidal PCs, periodic structures for molecular sieves, among others, the proposed technique could be a low cost alternative. In addition as we use biocompatible materials, this technique could be a tool for biophysics studies where the potential of large effective Soret coefficient could be useful.
Assembling of three-dimensional crystals by large nonequilibrium depletion force
Hai-Dong Deng; Ting Sun; Zhi-Cheng Fu; Hai-Ying Liu; Qiao-Feng Dai; Li-Jun Wu; Sheng Lan; Venu Gopal Achanta
2010-12-14T23:59:59.000Z
We propose and demonstrate a method to achieve large effective Soret coefficient in colloids by suitably mixing two different particles, e.g., silica beads and Fe3O4 nanoparticles. It is shown that the thermophoretic motion of Fe3O4 nanoparticles out of the heating region results in a large nonequlibrium depletion force for silica beads. Consequently, silica beads are driven quickly to the heating region, forming a three-dimensional crystal with few defects and dislocations. The binding of silica beads is so tight that a colloidal photonic crystal can be achieved after the complete evaporation of solvent, water. Thus, for fabrication of defect free colloidal PCs, periodic structures for molecular sieves, among others, the proposed technique could be a low cost alternative. In addition as we use biocompatible materials, this technique could be a tool for biophysics studies where the potential of large effective Soret coefficient could be useful.
R. Cameron; L. Gizon; T. L. Duvall Jr
2008-02-12T23:59:59.000Z
The propagation of solar waves through the sunspot of AR 9787 is observed using temporal cross-correlations of SOHO/MDI Dopplergrams. We then use three-dimensional MHD numerical simulations to compute the propagation of wave packets through self-similar magneto-hydrostatic sunspot models. The simulations are set up in such a way as to allow a comparison with observed cross-covariances (except in the immediate vicinity of the sunspot). We find that the simulation and the f-mode observations are in good agreement when the model sunspot has a peak field strength of 3 kG at the photosphere, less so for lower field strengths. Constraining the sunspot model with helioseismology is only possible because the direct effect of the magnetic field on the waves has been fully taken into account. Our work shows that the full-waveform modeling of sunspots is feasible.
THREE-DIMENSIONAL MODELING OF RELATIVISTIC COLLISIONLESS ION-ELECTRON SHOCKS
Haugboelle, Troels, E-mail: haugboel@nbi.dk [Centre for Star and Planet Formation, Natural History Museum of Denmark, University of Copenhagen, Oester Voldgade 5-7, DK-1350 Copenhagen (Denmark)
2011-10-01T23:59:59.000Z
Two-dimensional (2D) modeling of collisionless shocks has been of tremendous importance in understanding the physics of nonlinear evolution, momentum transfer, and particle acceleration, but current computer capacities have now reached a point where three-dimensional (3D) modeling is becoming feasible. We present the first 3D model of a fully developed and relaxed relativistic ion-electron shock, and analyze and compare it to similar 2D models. Quantitative and qualitative differences are found with respect to the 2D models. The shock jump conditions are naturally different, because of the extra degree of freedom, but in addition it is found that strong parallel electric fields develop at the shock interface, the level of magnetic field energy is lower, and the non-thermal particle distribution is shallower with a power-law index of {approx}2.2.
Particle Acceleration in three dimensional Reconnection Regions: A New Test Particle Approach
Rudiger Schopper; Guido T. Birk; Harald Lesch
2001-06-29T23:59:59.000Z
Magnetic Reconnection is an efficient and fast acceleration mechanism by means of direct electric field acceleration parallel to the magnetic field. Thus, acceleration of particles in reconnection regions is a very important topic in plasma astrophysics. This paper shows that the conventional analytical models and numerical test particle investigations can be misleading concerning the energy distribution of the accelerated particles, since they oversimplify the electric field structure by the assumption that the field is homogeneous. These investigations of the acceleration of charged test particles are extended by considering three-dimensional field configurations characterized by localized field-aligned electric fields. Moreover, effects of radiative losses are discussed. The comparison between homogeneous and inhomogeneous electric field acceleration in reconnection regions shows dramatic differences concerning both, the maximum particle energy and the form of the energy distribution.
Two-dimensional and three-dimensional Coulomb clusters in parabolic traps
D'yachkov, L. G., E-mail: dyachk@mail.ru; Myasnikov, M. I., E-mail: miasnikovmi@mail.ru [Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412 (Russian Federation); Petrov, O. F. [Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412 (Russian Federation); Moscow Institute of Physics and Technology (State University), Dolgoprudny 141700, Moscow Region (Russian Federation); Center for Astrophysics, Space Physics, and Engineering Research (CASPER), Baylor University, Waco, Texas 76798-7310 (United States); Hyde, T. W.; Kong, J.; Matthews, L. [Center for Astrophysics, Space Physics, and Engineering Research (CASPER), Baylor University, Waco, Texas 76798-7310 (United States)
2014-09-15T23:59:59.000Z
We consider the shell structure of Coulomb clusters in an axially symmetric parabolic trap exhibiting a confining potential U{sub c}(?,z)=(m?{sup 2}/2)(?{sup 2}+?z{sup 2}). Assuming an anisotropic parameter ??=?4 (corresponding to experiments employing a cusp magnetic trap under microgravity conditions), we have calculated cluster configurations for particle numbers N?=?3 to 30. We have shown that clusters with N???12 initially remain flat, transitioning to three-dimensional configurations as N increases. For N?=?8, we have calculated the configurations of minimal potential energy for all values of ? and found the points of configuration transitions. For N?=?13 and 23, we discuss the influence of both the shielding and anisotropic parameter on potential energy, cluster size, and shell structure.
Striation pattern of target particle and heat fluxes in three dimensional simulations for DIII-D
Frerichs, H.; Schmitz, O.; Reiter, D. [Institute of Energy and Climate Research—Plasma Physics, Forschungszentrum Jülich GmbH, Association EURATOM-FZJ, Partner in the Trilateral Euregio Cluster, Jülich (Germany)] [Institute of Energy and Climate Research—Plasma Physics, Forschungszentrum Jülich GmbH, Association EURATOM-FZJ, Partner in the Trilateral Euregio Cluster, Jülich (Germany); Evans, T. E. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)] [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Feng, Y. [Max-Planck Institute for Plasma Physics, Greifswald (Germany)] [Max-Planck Institute for Plasma Physics, Greifswald (Germany)
2014-02-15T23:59:59.000Z
The application of resonant magnetic perturbations results in a non-axisymmetric striation pattern of magnetic field lines from the plasma interior which intersect the divertor targets. The impact on related particle and heat fluxes is investigated by three dimensional computer simulations for two different recycling conditions (controlled via neutral gas pumping). It is demonstrated that a mismatch between the particle and heat flux striation pattern (splitting vs. no splitting), as is repeatedly observed in ITER similar shape H-mode plasmas at DIII-D, can be reproduced by the simulations for high recycling conditions at the onset of partial detachment. These results indicate that a detailed knowledge of the particle and energy balance is at least as important for realistic simulations as the consideration of a change in the magnetic field structure by plasma response effects.
Elastodynamic behavior of the three dimensional layer-by-layer metamaterial structure
Aravantinos-Zafiris, N.; Sigalas, M. M. [Department of Materials Science, University of Patras, 26504 Patras (Greece); Economou, E. N. [Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology—Hellas (FORTH), P.O. Box 1385, Heraklion GR-71110, Greece and Department of Physics, University of Crete, Heraklion GR-71003 (Greece)
2014-10-07T23:59:59.000Z
In this work, we numerically investigate for the first time the elastodynamic behavior of a three dimensional layer-by-layer rod structure, which is easy to fabricate and has already proved to be very efficient as a photonic crystal. The Finite Difference Time Domain method was used for the numerical calculations. For the rods, several materials were examined and the effects of all the geometric parameters of the structure were also numerically investigated. Additionally, two modifications of the structure were included in our calculations. The results obtained here (for certain geometric parameters), exhibiting a high ratio of longitudinal over transverse sound velocity and therefore a close approach to ideal pentamode behavior over a frequency range, clearly show that the layer-by-layer rod structure, besides being an efficient photonic crystal, is a very serious contender as an elastodynamic metamaterial.
The Three Dimensional Evolution to Core Collapse of a Massive Star
Couch, Sean M; Arnett, W David; Timmes, F X
2015-01-01T23:59:59.000Z
We present the first three dimensional (3D) simulation of the final minutes of iron core growth in a massive star, up to and including the point of core gravitational instability and collapse. We self-consistently capture the development of strong convection driven by violent Si burning in the shell surrounding the iron core. This convective burning builds the iron core to its critical (Chandrasekhar) mass and collapse ensues, driven by electron capture and photodisintegration. The non-spherical structure and motion (turbulent fluctuations) generated by 3D convection is substantial at the point of collapse. We examine the impact of such physically-realistic 3D initial conditions on the core-collapse supernova mechanism using 3D simulations including multispecies neutrino leakage. We conclude that non-spherical progenitor structure should not be ignored, and has a significant and favorable impact on the likelihood for neutrino-driven explosions.
High-resolution ab initio three-dimensional x-ray diffraction microscopy
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Chapman, Henry N.; Barty, Anton; Marchesini, Stefano; Noy, Aleksandr; Hau-Riege, Stefan P.; Cui, Congwu; Howells, Malcolm R.; Rosen, Rachel; He, Haifeng; Spence, John C.; et al
2006-01-01T23:59:59.000Z
Coherent x-ray diffraction microscopy is a method of imaging nonperiodic isolated objects at resolutions limited, in principle, by only the wavelength and largest scattering angles recorded. We demonstrate x-ray diffraction imaging with high resolution in all three dimensions, as determined by a quantitative analysis of the reconstructed volume images. These images are retrieved from the three-dimensional diffraction data using no a priori knowledge about the shape or composition of the object, which has never before been demonstrated on a nonperiodic object. We also construct two-dimensional images of thick objects with greatly increased depth of focus (without loss of transverse spatialmore »resolution). These methods can be used to image biological and materials science samples at high resolution with x-ray undulator radiation and establishes the techniques to be used in atomic-resolution ultrafast imaging at x-ray free-electron laser sources.« less
Conversion of the Bryan Mound geological site characterization reports to a three-dimensional model.
Stein, Joshua S.; Rautman, Christopher Arthur
2005-04-01T23:59:59.000Z
The Bryan Mound salt dome, located near Freeport, Texas, is home to one of four underground crude oil-storage facilities managed by the U. S. Department of Energy Strategic Petroleum Reserve (SPR) Program. Sandia National Laboratories, as the geotechnical advisor to the SPR, conducts site-characterization investigations and other longer-term geotechnical and engineering studies in support of the program. This report describes the conversion of two-dimensional geologic interpretations of the Bryan Mound site into three-dimensional geologic models. The new models include the geometry of the salt dome, the surrounding sedimentary units, mapped faults, and the 20 oil-storage caverns at the site. This work provides an internally consistent geologic model of the Bryan Mound site that can be used in support of future work.
Probe of Three-Dimensional Chiral Topological Insulators in an Optical Lattice
Sheng-Tao Wang; Dong-Ling Deng; Lu-Ming Duan
2014-07-17T23:59:59.000Z
We propose a feasible experimental scheme to realize a three-dimensional chiral topological insulator with cold fermionic atoms in an optical lattice, which is characterized by an integer topological invariant distinct from the conventional $Z_2$ topological insulators and has a remarkable macroscopic zero-energy flat band. To probe its property, we show that its characteristic surface states---the Dirac cones---can be probed through time-of-flight imaging or Bragg spectroscopy and the flat band can be detected via measurement of the atomic density profile in a weak global trap. The realization of this novel topological phase with a flat band in an optical lattice will provide a unique experimental platform to study the interplay between interaction and topology and open new avenues for application of topological states.
Strong Coupling Expansion in a Correlated Three-Dimensional Topological Insulator
Akihiko Sekine; Takashi Z. Nakano; Yasufumi Araki; Kentaro Nomura
2013-04-11T23:59:59.000Z
Motivated by recent studies which show that topological phases may emerge in strongly correlated electron systems, we theoretically study the strong electron correlation effect in a three-dimensional topological insulator, which effective Hamiltonian can be described by the Wilson fermions. We adopt 1/r long-range Coulomb interaction as the interaction between the bulk electrons. Based on the U(1) lattice gauge theory, the strong coupling expansion is applied by assuming that the effective interaction is strong. It is shown that the effect of the Coulomb interaction is equivalent to the renormalization of the bare mass of the Wilson fermions, and that as a result, the topological insulator phase survives in the strong coupling limit.
Development and anisotropy of three-dimensional turbulence in a current sheet
Onofri, M.; Veltri, P.; Malara, F. [Dipartimento di Fisica, Universita della Calabria, via P. Bucci, 87036 Rende (Serbia and Montenegro) (Italy)
2007-06-15T23:59:59.000Z
The nonlinear evolution of three-dimensional reconnection instabilities are studied in a current sheet where many resonant surfaces are simultaneously present at different locations of the simulation domain. The nonlinear evolution produces the development of anisotropic magnetohydrodynamic turbulence. The development of the energy spectrum is followed until the energy is transported to the dissipative length scale and the anisotropy of the spectrum is analyzed. The energy cascade is affected by the Alfven effect and it takes place mainly in the direction perpendicular to the local average magnetic field. Anisotropy is also affected by propagation of perturbations across the main magnetic field, due to the growth of a transverse component related to reconnection. The direction of anisotropy varies with the position in space. The spectral index is different both from what is found in homogeneous isotropic turbulence and from the values predicted for magnetohydrodynamic turbulence with a uniform large-scale magnetic field.
Thorne, P.D.; Chamness, M.A.; Vermeul, V.R.; Macdonald, Q.C.; Schubert, S.E.
1994-11-01T23:59:59.000Z
This report documents work conducted during the fiscal year 1994 to development an improved three-dimensional conceptual model of ground-water flow in the unconfined aquifer system across the Hanford Site Ground-Water Surveillance Project, which is managed by Pacific Northwest Laboratory. The main objective of the ongoing effort to develop an improved conceptual model of ground-water flow is to provide the basis for improved numerical report models that will be capable of accurately predicting the movement of radioactive and chemical contaminant plumes in the aquifer beneath Hanford. More accurate ground-water flow models will also be useful in assessing the impacts of changes in facilities and operations. For example, decreasing volumes of operational waste-water discharge are resulting in a declining water table in parts of the unconfined aquifer. In addition to supporting numerical modeling, the conceptual model also provides a qualitative understanding of the movement of ground water and contaminants in the aquifer.
Two-dimensional excitons in three-dimensional hexagonal boron nitride
Cao, X. K.; Lin, J. Y., E-mail: hx.jiang@ttu.edu; Jiang, H. X., E-mail: jingyu.lin@ttu.edu [Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409 (United States); Clubine, B.; Edgar, J. H. [Department of Chemical Engineering, Kansas State University, Manhattan, Kansas 66506 (United States)] [Department of Chemical Engineering, Kansas State University, Manhattan, Kansas 66506 (United States)
2013-11-04T23:59:59.000Z
The recombination processes of excitons in hexagonal boron nitride (hBN) have been probed using time-resolved photoluminescence. It was found that the theory for two-dimensional (2D) exciton recombination describes well the exciton dynamics in three-dimensional hBN. The exciton Bohr radius and binding energy deduced from the temperature dependent exciton recombination lifetime is around 8?Å and 740?meV, respectively. The effective masses of electrons and holes in 2D hBN deduced from the generalized relativistic dispersion relation of 2D systems are 0.54m{sub o}, which are remarkably consistent with the exciton reduced mass deduced from the experimental data. Our results illustrate that hBN represents an ideal platform to study the 2D optical properties as well as the relativistic properties of particles in a condensed matter system.
Three dimensional winds: A maximum cross-correlation application to elastic lidar data
Buttler, W.T.
1996-05-01T23:59:59.000Z
Maximum cross-correlation techniques have been used with satellite data to estimate winds and sea surface velocities for several years. Los Alamos National Laboratory (LANL) is currently using a variation of the basic maximum cross-correlation technique, coupled with a deterministic application of a vector median filter, to measure transverse winds as a function of range and altitude from incoherent elastic backscatter lidar (light detection and ranging) data taken throughout large volumes within the atmospheric boundary layer. Hourly representations of three-dimensional wind fields, derived from elastic lidar data taken during an air-quality study performed in a region of complex terrain near Sunland Park, New Mexico, are presented and compared with results from an Environmental Protection Agency (EPA) approved laser doppler velocimeter. The wind fields showed persistent large scale eddies as well as general terrain-following winds in the Rio Grande valley.
Three-dimensional field map of the Fermilab D0 detector
Ostiguy, J.; Yamada, R.
1991-08-01T23:59:59.000Z
The D0 detector is a general purpose hadron collider detector presently under construction at Fermilab and scheduled to be put in operation in the fall of 1991. The D0 muon detection system is composed of three major toroids referred to respectively as the Central Field (CF) toroid and the End Field (EF) toroids. The complete detector weighs in excess of 4000 metric tons and rests on a steel platform. The muon detection system was designed using standard 2D codes and flux maps inside were obtained for each of the toroids taken separately. Various magnetic field measurements were performed; discrepancies with the design calculations have been observed and attributed to three dimensional effects. In this paper, we compare the predictions of the 2D computations to 3D calculations for a fully assembled detector. We also estimate the electromagnetic forces between the toroids and discuss other 3D effects, in particular, the effect of the supporting platform. 4 refs., 3 figs.
Development and validation of a two-phase, three-dimensional model for PEM fuel cells.
Chen, Ken Shuang
2010-04-01T23:59:59.000Z
The objectives of this presentation are: (1) To develop and validate a two-phase, three-dimensional transport modelfor simulating PEM fuel cell performance under a wide range of operating conditions; (2) To apply the validated PEM fuel cell model to improve fundamental understanding of key phenomena involved and to identify rate-limiting steps and develop recommendations for improvements so as to accelerate the commercialization of fuel cell technology; (3) The validated PEMFC model can be employed to improve and optimize PEM fuel cell operation. Consequently, the project helps: (i) address the technical barriers on performance, cost, and durability; and (ii) achieve DOE's near-term technical targets on performance, cost, and durability in automotive and stationary applications.
Higgs Mechanism and Anomalous Hall Effect in Three-Dimensional Topological Superconductors
Nogueira, Flavio S; Eremin, Ilya
2015-01-01T23:59:59.000Z
We demonstrate that the Higgs mechanism in three-dimensional topological superconductors exhibits unique features with experimentally observable consequences. The Higgs model we discuss has two superconducting components and an axion-like magnetoelectric term with the phase difference of the superconducting order parameters playing the role of the axion field. Due to this additional term, quantum electromagnetic and phase fluctuations lead to a robust topologically non-trivial state that cannot be continuously deformed into a topologically non-trivial one. In the low frequency London regime an anomalous Hall effect is induced in the presence of an applied electric field parallel to the surface. This anomalous Hall current is induced by a Lorentz-like force arising from the axion term, and it involves the relative superfluid velocity of the superconducting components. The anomalous Hall current has a negative sign, a situation reminiscent, but quite distinct in physical origin, of the anomalous Hall effect obs...
Disorder driven itinerant quantum criticality of three dimensional massless Dirac fermions
Pixley, J H; Sarma, S Das
2015-01-01T23:59:59.000Z
The experimentally observed non-Fermi liquid behavior in many strange metals over a broad range of energy and temperature can often be understood by invoking their close proximity to a zero-temperature quantum critical point (e.g. high-temperature cuprate superconductors). Progress in our understanding of such quantum critical properties of itinerant electrons has been hindered by the lack of effective models which are amenable to controlled analytical and numerically exact calculations. Here we establish that the disorder driven semimetal to metal quantum phase transition of three dimensional massless Dirac fermions could serve as a paradigmatic toy model for studying itinerant quantum criticality, which is solved by exact numerical calculations and a controlled field theoretic analysis. As a result, we establish the robust existence of a non-Gaussian universality class, and also construct the relevant low energy effective field theory that could guide the understanding of quantum critical scaling for many s...
Yuya Sasai; Naoki Sasakura
2009-05-13T23:59:59.000Z
We investigate the unitarity of three dimensional noncommutative scalar field theory in the Lie algebraic noncommutative spacetime [x^i,x^j]=2i kappa epsilon^{ijk}x_k. This noncommutative field theory possesses a SL(2,R)/Z_2 group momentum space, which leads to a Hopf algebraic translational symmetry. We check the Cutkosky rule of the one-loop self-energy diagrams in the noncommutative phi^3 theory when we include a braiding, which is necessary for the noncommutative field theory to possess the Hopf algebraic translational symmetry at quantum level. Then, we find that the Cutkosky rule is satisfied if the mass is less than 1/(2^(1/2)kappa).
Three-dimensional carbon fibers and method and apparatus for their production
Muradov, Nazim Z. (Melbourne, FL)
2012-02-21T23:59:59.000Z
This invention relates to novel three-dimensional (3D) carbon fibers which are original (or primary) carbon fibers (OCF) with secondary carbon filaments (SCF) grown thereon, and, if desired, tertiary carbon filaments (TCF) are grown from the surface of SCF forming a filamentous carbon network with high surface area. The methods and apparatus are provided for growing SCF on the OCF by thermal decomposition of carbonaceous gases (CG) over the hot surface of the OCF without use of metal-based catalysts. The thickness and length of SCF can be controlled by varying operational conditions of the process, e.g., the nature of CG, temperature, residence time, etc. The optional activation step enables one to produce 3D activated carbon fibers with high surface area. The method and apparatus are provided for growing TCF on the SCF by thermal decomposition of carbonaceous gases over the hot surface of the SCF using metal catalyst particles.
Biologically Inspired Synthesis Route to Three-Dimensionally Structured Inorganic Thin Films
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Schwenzer, Birgit; Morse, Daniel E.
2008-01-01T23:59:59.000Z
Inorganic thin films (hydroxide, oxide, and phosphate materials) that are textured on a submicron scale have been prepared from aqueous metal salt solutions at room temperature using vapor-diffusion catalysis. This generic synthesis approach mimics the essential advantages of the catalytic and structure-directing mechanisms observed for the formation of silica skeletons of marine sponges. Chemical composition, crystallinity, and the three-dimensional morphology of films prepared by this method are extremely sensitive to changes in the synthesis conditions, such as concentrations, reaction times, and the presence and nature of substrate materials. Focusing on different materials systems, the reaction mechanism for the formation ofmore »these thin films and the influence of different reaction parameters on the product are explained.« less
Malone, R.C.; Auer, L.H.; Glatzmaier, G.A.; Wood, M.C.; Toon, O.B.
1986-01-20T23:59:59.000Z
We reexamine the ''nuclear winter'' hypothesis with a three-dimensional global model modified to allow for localized injection of smoke, its transport by the simulated winds, its absorption of sunlight, and its removal by model-simulated precipitation. Smoke injected into the troposphere is driven upward by solar heating. The tropopause, initially above the smoke, reforms below the heated smoke layer and separates it from precipitation below. Although much smoke is scavenged while the thermal structure is being altered, the residence time of the remaining smoke is greatly increased. We find, particularly for July conditions, a longer-lasting ''nuclear winter'' effect than was found in earlier modeling studies in which normal tropospheric residence times were assumed. In January the smaller solar flux in the northern hemisphere allows faster removal of smoke than in July. Significant cooling of the northern hemisphere continents is predicted; its dependence on season and injected smoke mass is described.
Atomic Scale Design and Three-Dimensional Simulation of Ionic Diffusive Nanofluidic Channels
Park, Jin Kyoung; We, Guo-Wei
2015-01-01T23:59:59.000Z
Recent advance in nanotechnology has led to rapid advances in nanofluidics, which has been established as a reliable means for a wide variety of applications, including molecular separation, detection, crystallization and biosynthesis. Although atomic and molecular level consideration is a key ingredient in experimental design and fabrication of nanfluidic systems, atomic and molecular modeling of nanofluidics is rare and most simulations at nanoscale are restricted to one- or two-dimensions in the literature, to our best knowledge. The present work introduces atomic scale design and three-dimensional (3D) simulation of ionic diffusive nanofluidic systems. We propose a variational multiscale framework to represent the nanochannel in discrete atomic and/or molecular detail while describe the ionic solution by continuum. Apart from the major electrostatic and entropic effects, the non-electrostatic interactions between the channel and solution, and among solvent molecules are accounted in our modeling. We deriv...
Specific heat and energy for the three-dimensional O(2) model
Holtmann, S; Schulze, T
2002-01-01T23:59:59.000Z
We investigate the three-dimensional O(2) model on lattices of size 8^3 to 160^3 close to the critical point at zero magnetic field. We confirm explicitly the value of the critical coupling J_c found by Ballesteros et al. and estimate there the universal values of g_r and xi/L. At the critical point we study the finite size dependencies of the energy density epsilon and the specific heat C. We find that the nonsingular part of the specific heat C_{ns} is linearly dependent on 1/alpha. From the critical behaviour of the specific heat for T not T_c on the largest lattices we determine the universal amplitude ratio A+/A-. The alpha- dependence of this ratio is close to the phenomenological relation A+/A- = 1-4alpha.
O'Neill, S M
2010-01-01T23:59:59.000Z
We report on a series of three-dimensional magnetohydrodynamic simulations of active galactic nucleus (AGN) jet propagation in realistic models of magnetized galaxy clusters. We are primarily interested in the details of energy transfer between jets and the intracluster medium (ICM) to help clarify what role such flows could have in the reheating of cluster cores. Our simulated jets feature a range of intermittency behaviors, including intermittent jets that periodically switch on and off and one model jet that shuts down completely, naturally creating a relic plume. The ICM into which these jets propagate incorporates tangled magnetic field geometries and density substructure designed to mimic some likely features of real galaxy clusters. We find that our jets are characteristically at least 60% efficient at transferring thermal energy to the ICM. Irreversible heat energy is not uniformly distributed, however, instead residing preferentially in regions very near the jet/cocoon boundaries. While intermittency...
CONSTRAINING THREE-DIMENSIONAL MAGNETIC FIELD EXTRAPOLATIONS USING THE TWIN PERSPECTIVES OF STEREO
Conlon, Paul A.; Gallagher, Peter T. [Astrophysics Research Group, School of Physics, Trinity College Dublin, Dublin 2 (Ireland)
2010-05-20T23:59:59.000Z
The three-dimensional magnetic topology of a solar active region (NOAA 10956) was reconstructed using a linear force-free field extrapolation constrained using the twin perspectives of STEREO. A set of coronal field configurations was initially generated from extrapolations of the photospheric magnetic field observed by the Michelson Doppler Imager on SOHO. Using an EUV intensity-based cost function, the extrapolated field lines that were most consistent with 171 A passband images from the Extreme UltraViolet Imager on STEREO were identified. This facilitated quantitative constraints to be placed on the twist ({alpha}) of the extrapolated field lines, where {nabla} x B = {alpha}B. Using the constrained values of {alpha}, the evolution in time of twist, connectivity, and magnetic energy were then studied. A flux emergence event was found to result in significant changes in the magnetic topology and total magnetic energy of the region.
Hoffman, E.L.; Ehgartner, B.L.
1998-02-01T23:59:59.000Z
Three-dimensional quasistatic finite element codes are being used at Sandia National Laboratories to simulate the interactions of multiple large room and pillar mines in rock salt. The calculations presented in this paper are of a salt dome which contains multiple closely-spaced room and pillar mines. One of the mines was used as an oil storage facility, supported by the US DOE under the auspices of the Strategic Petroleum Reserve (SPR) program. The facility has recently been decommissioned due to the discovery of geotechnical instabilities. The model, validated by field observations, has resulted in a better understanding of the mechanisms which can threaten the stability of an underground excavation, as well as the structural interactions of multiple excavations. Although these calculations were performed in the specific interest of the SPR, the results should be of interest to mine designers concerned with the interactions of multiple mines excavated in a common formation.
High-resolution ab initio three-dimensional x-ray diffraction microscopy
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Chapman, Henry N.; Barty, Anton; Marchesini, Stefano; Noy, Aleksandr; Hau-Riege, Stefan P.; Cui, Congwu; Howells, Malcolm R.; Rosen, Rachel; He, Haifeng; Spence, John C.; Weierstall, Uwe; Beetz, Tobias; Jacobsen, Chris; Shapiro, David
2006-01-01T23:59:59.000Z
Coherent x-ray diffraction microscopy is a method of imaging nonperiodic isolated objects at resolutions limited, in principle, by only the wavelength and largest scattering angles recorded. We demonstrate x-ray diffraction imaging with high resolution in all three dimensions, as determined by a quantitative analysis of the reconstructed volume images. These images are retrieved from the three-dimensional diffraction data using no a priori knowledge about the shape or composition of the object, which has never before been demonstrated on a nonperiodic object. We also construct two-dimensional images of thick objects with greatly increased depth of focus (without loss of transverse spatial resolution). These methods can be used to image biological and materials science samples at high resolution with x-ray undulator radiation and establishes the techniques to be used in atomic-resolution ultrafast imaging at x-ray free-electron laser sources.
Conversion of the Big Hill geological site characterization report to a three-dimensional model.
Stein, Joshua S.; Rautman, Christopher Arthur
2003-02-01T23:59:59.000Z
The Big Hill salt dome, located in southeastern Texas, is home to one of four underground oil-storage facilities managed by the U. S. Department of Energy Strategic Petroleum Reserve (SPR) Program. Sandia National Laboratories, as the geotechnical advisor to the SPR, conducts site-characterization investigations and other longer-term geotechnical and engineering studies in support of the program. This report describes the conversion of two-dimensional geologic interpretations of the Big Hill site into three-dimensional geologic models. The new models include the geometry of the salt dome, the surrounding sedimentary units, mapped faults, and the 14 oil storage caverns at the site. This work provides a realistic and internally consistent geologic model of the Big Hill site that can be used in support of future work.
Stein, Joshua S.; Rautman, Christopher Arthur; Snider, Anna C.
2004-08-01T23:59:59.000Z
The West Hackberry salt dome, in southwestern Louisiana, is one of four underground oil-storage facilities managed by the U. S. Department of Energy Strategic Petroleum Reserve (SPR) Program. Sandia National Laboratories, as the geotechnical advisor to the SPR, conducts site-characterization investigations and other longer-term geotechnical and engineering studies in support of the program. This report describes the conversion of two-dimensional geologic interpretations of the West Hackberry site into three-dimensional geologic models. The new models include the geometry of the salt dome, the surrounding sedimentary layers, mapped faults, and a portion of the oil storage caverns at the site. This work provides a realistic and internally consistent geologic model of the West Hackberry site that can be used in support of future work.
Three-dimensional architecture of hair-cell linkages as revealedby electron-microscopic tomography
Auer, Manfred; Koster, Bram; Ziese, Ulrike; Bajaj, Chandrajit; Volkmann, Niels; Wang, Da Neng; Hudspeth, A. James
2006-07-28T23:59:59.000Z
The senses of hearing and balance rest upon mechanoelectrical transduction by the hair bundles of hair cells in the inner ear. Located at the apical cellular surface, each hair bundle comprises several tens of stereocilia and a single kinocilium that are interconnected by extracellular proteinaceous links. Using electron-microscopic tomography of bullfrog saccular sensory epithelia, we examined the three-dimensional structures of ankle or basal links, kinociliary links, and tip links. We observed clear differences in the dimensions and appearances of the three links. We found two distinct populations of tip links suggestive of the involvement of two proteins or splice variants. We noted auxiliary links connecting the upper portions of tip links to the taller stereocilia. Tip links and auxiliary links show a tendency to adopt a globular conformation when disconnected from the membrane surface.
Dynamics of impurities in a three-dimensional volume-preserving map
Swetamber Das; Neelima Gupte
2014-06-17T23:59:59.000Z
We study the dynamics of inertial particles in three dimensional incompressible maps, as representations of volume preserving flows. The impurity dynamics has been modeled, in the Lagrangian framework, by a six-dimensional dissipative bailout embedding map. The fluid-parcel dynamics of the base map is embedded in the particle dynamics governed by the map. The base map considered for the present study is the Arnold-Beltrami-Childress (ABC) map. We consider the behavior of the system both in the aerosol regime, where the density of the particle is larger than that of the base flow, as well as the bubble regime, where the particle density is less than that of the base flow. The phase spaces in both the regimes show rich and complex dynamics with three type of dynamical behaviors - chaotic structures, regular orbits and hyperchaotic regions. In the one-action case, the aerosol regime is found to have periodic attractors for certain values of the dissipation and inertia parameters. For the aerosol regime of the two-action ABC map, an attractor merging and widening crises is identified using the bifurcation diagram and the spectrum of Lyapunov exponents. After the crisis an attractor with two parts is seen, and trajectories hop between these parts with period 2. The bubble regime of the embedded map shows strong hyperchaotic regions as well as crisis induced intermittency with characteristic times between bursts that scale as a power law behavior as a function of the dissipation parameter. Furthermore, we observe riddled basin of attraction and unstable dimension variability in the phase space in the bubble regime. The bubble regime in one-action shows similar behavior. This study of a simple model of impurity dynamics may shed light upon the transport properties of passive scalars in three dimensional flows. We also compare our results with those seen earlier in two dimensional flows.
A seamless acquisition digital storage oscilloscope with three-dimensional waveform display
Yang, Kuojun, E-mail: kuojunyang@gmail.com; Guo, Lianping [School of Automation Engineering, University of Electronic Science and Technology of China, Chengdu (China) [School of Automation Engineering, University of Electronic Science and Technology of China, Chengdu (China); School of Electrical and Electronic Engineering, Nanyang Technological University (Singapore); Tian, Shulin; Zeng, Hao [School of Automation Engineering, University of Electronic Science and Technology of China, Chengdu (China)] [School of Automation Engineering, University of Electronic Science and Technology of China, Chengdu (China); Qiu, Lei [School of Electrical and Electronic Engineering, Nanyang Technological University (Singapore)] [School of Electrical and Electronic Engineering, Nanyang Technological University (Singapore)
2014-04-15T23:59:59.000Z
In traditional digital storage oscilloscope (DSO), sampled data need to be processed after each acquisition. During data processing, the acquisition is stopped and oscilloscope is blind to the input signal. Thus, this duration is called dead time. With the rapid development of modern electronic systems, the effect of infrequent events becomes significant. To capture these occasional events in shorter time, dead time in traditional DSO that causes the loss of measured signal needs to be reduced or even eliminated. In this paper, a seamless acquisition oscilloscope without dead time is proposed. In this oscilloscope, three-dimensional waveform mapping (TWM) technique, which converts sampled data to displayed waveform, is proposed. With this technique, not only the process speed is improved, but also the probability information of waveform is displayed with different brightness. Thus, a three-dimensional waveform is shown to the user. To reduce processing time further, parallel TWM which processes several sampled points simultaneously, and dual-port random access memory based pipelining technique which can process one sampling point in one clock period are proposed. Furthermore, two DDR3 (Double-Data-Rate Three Synchronous Dynamic Random Access Memory) are used for storing sampled data alternately, thus the acquisition can continue during data processing. Therefore, the dead time of DSO is eliminated. In addition, a double-pulse test method is adopted to test the waveform capturing rate (WCR) of the oscilloscope and a combined pulse test method is employed to evaluate the oscilloscope's capture ability comprehensively. The experiment results show that the WCR of the designed oscilloscope is 6?250?000 wfms/s (waveforms per second), the highest value in all existing oscilloscopes. The testing results also prove that there is no dead time in our oscilloscope, thus realizing the seamless acquisition.
Hadron Optics in Three-Dimensional Invariant Coordinate Space from Deeply Virtual Compton Scattering
S. J. Brodsky; D. Chakrabarti; A. Harindranath; A. Mukherjee; J. P. Vary
2006-11-28T23:59:59.000Z
The Fourier transform of the deeply virtual Compton scattering amplitude (DVCS) with respect to the skewness parameter \\zeta= Q^2/ 2 p.q can be used to provide an image of the target hadron in the boost-invariant variable \\sigma, the coordinate conjugate to light-front time \\tau=t+ z/ c. As an illustration, we construct a consistent covariant model of the DVCS amplitude and its associated generalized parton distributions using the quantum fluctuations of a fermion state at one loop in QED, thus providing a representation of the light-front wavefunctions of a lepton in \\sigma space. A consistent model for hadronic amplitudes can then be obtained by differentiating the light-front wavefunctions with respect to the bound-state mass. The resulting DVCS helicity amplitudes are evaluated as a function of \\sigma and the impact parameter \\vec b_\\perp, thus providing a light-front image of the target hadron in a frame-independent three-dimensional light-front coordinate space. Models for the LFWFs of hadrons in (3+1) dimensions displaying confinement at large distances and conformal symmetry at short distances have been obtained using the AdS/CFT method. We also compute the LFWFs in this model in invariant three dimensional coordinate space. We find that in the models studied, the Fourier transform of the DVCS amplitudes exhibit diffraction patterns. The results are analogous to the diffractive scattering of a wave in optics where the distribution in \\sigma measures the physical size of the scattering center in a one-dimensional system.
Jain, Anudh K. [Department of Radiation Oncology, Mayo Clinic, Jacksonville, Florida (United States); Vallow, Laura A. [Department of Radiation Oncology, Mayo Clinic, Jacksonville, Florida (United States)], E-mail: vallow.laura@mayo.edu; Gale, Ashley A.; Buskirk, Steven J. [Department of Radiation Oncology, Mayo Clinic, Jacksonville, Florida (United States)
2009-09-01T23:59:59.000Z
Purpose: To determine whether three-dimensional conformal partial breast irradiation (3D-PBI) spares lung tissue compared with whole breast irradiation (WBI) and to include the biologically equivalent dose (BED) to account for differences in fractionation. Methods and Materials: Radiotherapy treatment plans were devised for WBI and 3D-PBI for 25 consecutive patients randomized on the NSABP B-39/RTOG 0413 protocol at Mayo Clinic in Jacksonville, Florida. WBI plans were for 50 Gy in 25 fractions, and 3D-PBI plans were for 38.5 Gy in 10 fractions. Volume of ipsilateral lung receiving 2.5, 5, 10, and 20 Gy was recorded for each plan. The linear quadratic equation was used to calculate the corresponding dose delivered in 10 fractions and volume of ipsilateral lung receiving these doses was recorded for PBI plans. Ipsilateral mean lung dose was recorded for each plan and converted to BED. Results: There was a significant decrease in volume of lung receiving 20 Gy with PBI (median, 4.4% vs. 7.5%; p < 0.001), which remained after correction for fractionation (median, 5.6% vs. 7.5%; p = 0.02). Mean lung dose was lower for PBI (median, 3.46 Gy vs. 4.57 Gy; p = 0.005), although this difference lost significance after conversion to BED (median, 3.86 Gy{sub 3} vs 4.85 Gy{sub 3}, p = 0.07). PBI plans exposed more lung to 2.5 and 5 Gy. Conclusions: 3D-PBI exposes greater volumes of lung tissue to low doses of radiation and spares the amount of lung receiving higher doses when compared with WBI.
Takase, Kazuyuki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan)
1997-05-01T23:59:59.000Z
Thermal-hydraulic characteristics in a spacer-ribbed annular fuel channel for high-temperature gas-cooled reactors were analyzed numerically by three-dimensional computations under a fully developed turbulent flow. The two-equation {kappa}-{epsilon} turbulence model was applied in the present turbulent analysis, and the turbulence model constants for eddy viscosity and the turbulent Prandtl number were improved from the previous standard values to increase the accuracy of numerical simulations. Consequently, heat transfer coefficients and friction factors in the spacer-ribbed fuel channel were predicted with sufficient accuracy in the range of Reynolds number >3,000. It was clarified quantitatively that the main mechanism for heat transfer augmentation in the spacer-ribbed fuel channel was a combined effect of the turbulence promoter effect by the spacer rib and the velocity acceleration effect by a reduction in the channel cross section.
Shalaby, M.; Khaled, M. A. [Department of Physics, Faculty of Science, Ain Shams University, Cairo, 11566 (Egypt); EL-Labany, S. K.; EL-Shamy, E. F. [Department of Physics, Faculty of Science, Mansoura University, Damietta Branch, Damietta El-Gedida 34517 (Egypt)
2010-11-15T23:59:59.000Z
The nonlinear propagation of dust ion-acoustic solitary waves (DIASWs) in a magnetized dusty plasma which consists of two different types of nonisothermal electrons, hot adiabatic inertial ions fluid and immobile negatively charged dust particles is studied. The modified Zakharov-Kuznetsov (MZK) equation, describing the small but finite amplitude DIASWs, is derived using a reductive perturbation method. The combined effects of the external magnetic field, obliqueness (i.e., the propagation angle), and the two-temperature nonisothermal electrons, which are found to significantly modify the basic properties of DIASWs, are explicitly examined. The three-dimensional instability of DIASWs is also analyzed using the small-k (long wavelength plane wave) perturbation expansion technique. The results show that the external magnetic field, the propagation angle, and the two-temperature nonisothermal electrons have strong effects on the instability criterion as well as the growth rate.
Mistry, Pradeep Champaklal
2002-01-01T23:59:59.000Z
and simulation results about the synchronous thermal instability phenomenon known as Morton Effect is presented in this dissertation. iv A transient analysis of the rotor supported by tilting pad journal bearing is performed to obtain asymmetric temperature... distribution of the journal by solving variable viscosity Reynolds equation, energy equation, heat conduction equation, and equations of motion for rotor. The tilting pad bearing is fully nonlinear model. In addition, thermal mode approach and staggered...
The Joint Cascade of Energy and Helicity in Three-Dimensional Turbulence
Qiaoning Chen; Shiyi Chen; Gregory L. Eyink
2002-06-18T23:59:59.000Z
Three-dimensional (3D) turbulence has both energy and helicity as inviscid constants of motion. In contrast to two-dimensional (2D) turbulence, where a second inviscid invariant--the enstrophy--blocks the energy cascade to small scales, in 3D there is a joint cascade of both energy and helicity simultaneously to small scales. The basic cancellation mechanism which permits a joint cascade of energy and helicity is illuminated by means of the helical decomposition of the velocity into positively and negatively polarized waves. This decomposition is employed in the present study both theoretically and also in a numerical simulation of homogeneous and isotropic 3D turbulence. It is shown that the transfer of energy to small scales produces a tremendous growth of helicity separately in the + and - helical modes at high wavenumbers, diverging in the limit of infinite Reynolds number. However, because of a tendency to restore reflection invariance at small scales, the net helicity from both modes remains finite in that limit. The net helicity flux is shown to be constant all the way up to the Kolmogorov wavenumber: there is no shorter inertial-range for helicity cascade than for energy cascade. The transfer of energy and helicity between + and - modes, which permits the joint cascade, is shown to be due to two distinct physical processes, advection and vortex stretching.
Short- and Long- Time Transport Structures in a Three Dimensional Time Dependent Flow
Rodolphe Chabreyrie; Stefan G. Llewellyn Smith
2014-05-08T23:59:59.000Z
Lagrangian transport structures for three-dimensional and time-dependent fluid flows are of great interest in numerous applications, particularly for geophysical or oceanic flows. In such flows, chaotic transport and mixing can play important environmental and ecological roles, for examples in pollution spills or plankton migration. In such flows, where simulations or observations are typically available only over a short time, understanding the difference between short-time and long-time transport structures is critical. In this paper, we use a set of classical (i.e. Poincar\\'e section, Lyapunov exponent) and alternative (i.e. finite time Lyapunov exponent, Lagrangian coherent structures) tools from dynamical systems theory that analyze chaotic transport both qualitatively and quantitatively. With this set of tools we are able to reveal, identify and highlight differences between short- and long-time transport structures inside a flow composed of a primary horizontal contra-rotating vortex chain, small lateral oscillations and a weak Ekman pumping. The difference is mainly the existence of regular or extremely slowly developing chaotic regions that are only present at short time.
Three-dimensional theory of quantum memories based on {Lambda}-type atomic ensembles
Zeuthen, Emil; Grodecka-Grad, Anna; Soerensen, Anders S. [QUANTOP, Danish National Research Foundation Center for Quantum Optics, Niels Bohr Institute, University of Copenhagen, DK-2100 Copenhagen O (Denmark)
2011-10-15T23:59:59.000Z
We develop a three-dimensional theory for quantum memories based on light storage in ensembles of {Lambda}-type atoms, where two long-lived atomic ground states are employed. We consider light storage in an ensemble of finite spatial extent and we show that within the paraxial approximation the Fresnel number of the atomic ensemble and the optical depth are the only important physical parameters determining the quality of the quantum memory. We analyze the influence of these parameters on the storage of light followed by either forward or backward read-out from the quantum memory. We show that for small Fresnel numbers the forward memory provides higher efficiencies, whereas for large Fresnel numbers the backward memory is advantageous. The optimal light modes to store in the memory are presented together with the corresponding spin waves and outcoming light modes. We show that for high optical depths such {Lambda}-type atomic ensembles allow for highly efficient backward and forward memories even for small Fresnel numbers F(greater-or-similar sign)0.1.
Takahiro Kudoh; Shantanu Basu
2008-04-27T23:59:59.000Z
We demonstrate that the formation of collapsing cores in subcritical clouds is accelerated by nonlinear flows, by performing three-dimensional non-ideal MHD simulations. An initial random supersonic (and trans-Alfvenic) turbulent-like flow is input into a self-gravitating gas layer that is threaded by a uniform magnetic field (perpendicular to the layer) such that the initial mass-to-flux ratio is subcritical. Magnetic ambipolar diffusion occurs very rapidly initially due to the sharp gradients introduced by the turbulent flow. It subsequently occurs more slowly in the traditional near-quasistatic manner, but in regions of greater mean density than present in the initial state. The overall timescale for runaway growth of the first core(s) is several times, 10^6 yr, even though previous studies have found a timescale of several times, 10^7 yr when starting with linear perturbations and similar physical parameters. Large-scale supersonic flows exist in the cloud and provide an observationally testable distinguishing characteristic from core formation due to linear initial perturbations. However, the nonlinear flows have decayed sufficiently that the relative infall motions onto the first core are subsonic, as in the case of starting from linear initial perturbations. The ion infall motions are very similar to those of neutrals; however, they lag the neutral infall in directions perpendicular to the mean magnetic field direction and lead the neutral infall in the direction parallel to the mean magnetic field.
Structure and trapping of three-dimensional dust clouds in a capacitively coupled rf-discharge
Arp, O.; Block, D.; Piel, A. [IEAP, Christian-Albrechts-University, D-24098 Kiel (Germany)
2005-10-31T23:59:59.000Z
In this survey the recently found 'Coulomb balls' are discussed, which show an unusual kind of crystalline order. These three-dimensional dust clouds consisting of hundreds or thousands of micrometer-sized dust particles have a spherical shape and exist in a wide range of plasma conditions. Coulomb balls are optically highly transparent and have macroscopic dimensions of several millimeters in diameter. The clouds allow for the observation of each single particle and thus the complete reconstruction of the crystal structure by means of video microscopy techniques. The particles are arranged in distinct nested shells in which they form patterns with mostly five and six neighbors. The confinement of Coulomb balls by dielectric walls involves electric forces, surface charges, ion drag forces, and thermophoretic levitation. The thermophoretic force field is measured with tracer particles and particle image velocimetry (PIV). The electric forces are derived from simulations with the two-dimensional SIGLO-2D code. It is shown the the sum of all confining forces results in a stable potential well that describes levitation and spherical confinement of the Coulomb ball.
Optimization of three-dimensional micropost microcavities for cavity quantum electrodynamics
Jelena Vuckovic; Matthew Pelton; Axel Scherer; Yoshihisa Yamamoto
2002-08-21T23:59:59.000Z
This article presents a detailed analysis, based on the first-principles finite-difference time-domain method, of the resonant frequency, quality factor (Q), mode volume (V), and radiation pattern of the fundamental (HE11) mode in a three-dimensional distributed-Bragg-reflector (DBR) micropost microcavity. By treating this structure as a one-dimensional cylindrical photonic crystal containing a single defect, we are able to push the limits of Q/V beyond those achievable by standard micropost designs, based on the simple rules established for planar DBR microcavities. We show that some of the rules that work well for designing large-diameter microposts (e.g., high-refractive index contrast) fail to provide high-quality cavities with small diameters. By tuning the thicknesses of mirror layers and the spacer, the number of mirror pairs, the refractive indices of high and low refractive index regions, and the cavity diameter, we are able to achieve Q as high as 10^4, together with a mode volume of 1.6 cubic wavelengths of light in the high-refractive-index material. The combination of high Q and small V makes these structures promising candidates for the observation of such cavity quantum electrodynamics phenomena as strong coupling between a quantum dot and the cavity field, and single-quantum-dot lasing.
Surface electronic states in three-dimensional SnO{sub 2} nanostructures
Kucheyev, S.O.; Baumann, T.F.; Sterne, P.A.; Wang, Y.M.; Buuren, T. van; Hamza, A.V.; Terminello, L.J.; Willey, T.M. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)
2005-07-15T23:59:59.000Z
The electronic structure of three-dimensional SnO{sub 2} nanostructures (aerogels) is studied by soft x-ray absorption near-edge structure (XANES) spectroscopy. High-resolution O K-edge and Sn M{sub 3}- and M{sub 4,5}-edge XANES spectra of monolithic nanocrystalline rutile SnO{sub 2} aerogels with different surface areas (i.e., different surface-to-volume atom fractions) are compared with spectra of full-density rutile SnO{sub 2} and tetragonal SnO. Spectra are interpreted based on the electronic densities of states in SnO{sub 2} calculated with both cluster (self-consistent real-space multiple scattering) and band-structure (linear muffin-tin orbital) methods. Results show that, in contrast to the currently widely accepted picture, the presence of undercoordinated surface atoms not only affects the Fermi level position but also changes the structure of the conduction band by introducing additional Sn-related electronic states close to the conduction band minimum. These additional states are due to oxygen deficiency and are attributed to a surface reconstruction of SnO{sub 2} nanoparticles forming the aerogel skeleton. Results of this study are important for understanding the physical processes underlying the performance of gas sensors based on SnO{sub 2} nanostructures.
Three dimensional neutronics calculation comparison study for a fusion breeder with large channels
Huang, J.H.; Xie, Z.Y.; You, C.L. [Southwestern Inst. of Physics, Chengdu (China)] [and others
1994-12-31T23:59:59.000Z
A tokamak reactor is characterized by a toroidal geometry with large ports and channels. The three dimensional calculation seems necessary for the prediction of the neutronics parameters of the calculation. People have been attempting to simulate the configuration by one dimensional model. Assuming that the neutronics parameters such as tritium breeding ratio depends almost only on the primary 14 MeV neutron number entering the blanket, the following approximate scheme was proposed: {Alpha} = {Sigma}W{sub i}{sm_bullet}{Alpha}{sub i}, where {Alpha} represents the total value of a parameter; {Alpha}{sub i} is a partial value contributed from the i`th part of the blanket and is calculated by a 1-D cylindrical model; W{sub i} is the fusion number entering the i`th part of the blanket through the first wall. This scheme seems reasonable for a pure fusion reactor with similar inboard and outboard blankets, since neutron flux angular distribution is strongly forward and the mutual influence between similar blankets is weak. A study on influence between inboard and outboard blankets showed a rather strong influence between blankets in a fusion breeder, where the partial blankets are quite different in neutronics characteristics. The explanation is that the neutron source from fission and n,2n reactions in the outboard blanket causes considerable neutron leakage through the inner surface when it faces an {open_quote}inferior{close_quote} inboard blanket.
Amber T. Krummel; Sujit S. Datta; Stefan Münster; David A. Weitz
2013-01-21T23:59:59.000Z
We report an approach to fully visualize the flow of two immiscible fluids through a model three-dimensional (3D) porous medium at pore-scale resolution. Using confocal microscopy, we directly image the drainage of the medium by the non-wetting oil and subsequent imbibition by the wetting fluid. During imbibition, the wetting fluid pinches off threads of oil in the narrow crevices of the medium, forming disconnected oil ganglia. Some of these ganglia remain trapped within the medium. By resolving the full 3D structure of the trapped ganglia, we show that the typical ganglion size, and the total amount of residual oil, decreases as the capillary number Ca increases; this behavior reflects the competition between the viscous pressure in the wetting fluid and the capillary pressure required to force oil through the pores of the medium. This work thus shows how pore-scale fluid dynamics influence the trapped fluid configurations in multiphase flow through 3D porous media.
Hammel, P.C.; Moore, G.; Roukes, M.; Zhenyong Zhang
1996-10-01T23:59:59.000Z
This is the final report of a two-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project successfully developed a magnetic resonance force microscope (MRFM) instrument to mechanically detect magnetic resonance signals. This technique provides an intrinsically subsurface, chemical-species-specific probe of structure, constituent density and other properties of materials. As in conventional magnetic resonance imaging (MRI), an applied magnetic field gradient selects a well defined volume of the sample for study. However mechanical detection allows much greater sensitivity, and this in turn allows the reduction of the size of the minimum resolvable volume. This requires building an instrument designed to achieve nanometer-scale resolution at buried semiconductor interfaces. High-resolution, three-dimensional depth profiling of semiconductors is critical in the development and fabrication of semiconductor devices. Currently, there is no capability for direct, high-resolution observation and characterization of dopant density, and other critical features of semiconductors. The successful development of MRFM in conjunction with modifications to improve resolution will enable for the first time detailed structural and electronic studies in doped semiconductors and multilayered nanoelectronic devices, greatly accelerating the current pace of research and development.
Burke, Micheal, E-mail: micheal.burke@tyndall.ie; Blake, Alan; Djara, Vladimir; O'Connell, Dan; Povey, Ian M.; Cherkaoui, Karim; Monaghan, Scott; Scully, Jim; Murphy, Richard; Hurley, Paul K.; Pemble, Martyn E.; Quinn, Aidan J., E-mail: aidan.quinn@tyndall.ie [Tyndall National Institute, University College Cork, Cork (Ireland)
2015-01-01T23:59:59.000Z
The authors report on the structural and electrical properties of TiN/Al{sub 2}O{sub 3}/TiN metal–insulator–metal (MIM) capacitor structures in submicron three-dimensional (3D) trench geometries with an aspect ratio of ?30. A simplified process route was employed where the three layers for the MIM stack were deposited using atomic layer deposition (ALD) in a single run at a process temperature of 250?°C. The TiN top and bottom electrodes were deposited via plasma-enhanced ALD using a tetrakis(dimethylamino)titanium precursor. 3D trench devices yielded capacitance densities of 36 fF/?m{sup 2} and quality factors >65 at low frequency (200?Hz), with low leakage current densities (<3 nA/cm{sup 2} at 1 V). These devices also show strong optical iridescence which, when combined with the covert embedded capacitance, show potential for system in package (SiP) anticounterfeiting applications.
G. J. Moridis; Y. Seol
2007-01-26T23:59:59.000Z
The authors investigated colloid transport in the unsaturated fractured zone by means of three-dimensional site-scale numerical model under present-day climate infiltration, considering varying colloid diameters, kinetic declogging, and filtration. The radionuclide transport model was used to simulate continuous release of colloids into fractures throughout the proposed repository, in which any components of engineered barrier system such as waste package or drip shield were not considered. the results of the study indicate the importance of subsurface geology and site hydrology, i.e., the presence of faults (they dominate and control transport), fractures (the main migration pathways), and the relative distribution of zeolitic and vitric tuffs. The simulations indicate that (1) colloid transport is not significantly affected by varying the filtration parameters, (2) travel time to the water table decreases with the colloid size, (3) larger colloids show little retardation whereas very small ones are retarded significantly, and (4) fracture filtration can have an impact on transport. Because of uncertainties in the fundamentals of colloid transport and an extremely conservative approach (based on an improbably adverse worst-case scenario), caution should be exercised in the analysis and interpretation of the 3-D simulation results. The results discussed here should be viewed as an attempt to identify and evaluate the mechanisms, processes, and geological features that control colloidal transport.
Puthen-Veettil, B., E-mail: b.puthen-veettil@unsw.edu.au; Patterson, R.; König, D.; Conibeer, G.; Green, M. A. [Australian Centre for Advanced Photovoltaics, UNSW, Sydney 2052 (Australia)
2014-10-28T23:59:59.000Z
Efficient iso-entropic energy filtering of electronic waves can be realized through nanostructures with three dimensional confinement, such as quantum dot resonant tunneling structures. Large-area deployment of such structures is useful for energy selective contacts but such configuration is susceptible to structural disorders. In this work, the transport properties of quantum-dot-based wide-area resonant tunneling structures, subject to realistic disorder mechanisms, are studied. Positional variations of the quantum dots are shown to reduce the resonant transmission peaks while size variations in the device are shown to reduce as well as broaden the peaks. Increased quantum dot size distribution also results in a peak shift to lower energy which is attributed to large dots dominating transmission. A decrease in barrier thickness reduces the relative peak height while the overall transmission increases dramatically due to lower “series resistance.” While any shift away from ideality can be intuitively expected to reduce the resonance peak, quantification allows better understanding of the tolerances required for fabricating structures based on resonant tunneling phenomena/.
Lee, H.R.
1997-11-18T23:59:59.000Z
A three-dimensional image reconstruction method comprises treating the object of interest as a group of elements with a size that is determined by the resolution of the projection data, e.g., as determined by the size of each pixel. One of the projections is used as a reference projection. A fictitious object is arbitrarily defined that is constrained by such reference projection. The method modifies the known structure of the fictitious object by comparing and optimizing its four projections to those of the unknown structure of the real object and continues to iterate until the optimization is limited by the residual sum of background noise. The method is composed of several sub-processes that acquire four projections from the real data and the fictitious object: generate an arbitrary distribution to define the fictitious object, optimize the four projections, generate a new distribution for the fictitious object, and enhance the reconstructed image. The sub-process for the acquisition of the four projections from the input real data is simply the function of acquiring the four projections from the data of the transmitted intensity. The transmitted intensity represents the density distribution, that is, the distribution of absorption coefficients through the object. 5 figs.
Lee, Heung-Rae (Dublin, CA)
1997-01-01T23:59:59.000Z
A three-dimensional image reconstruction method comprises treating the object of interest as a group of elements with a size that is determined by the resolution of the projection data, e.g., as determined by the size of each pixel. One of the projections is used as a reference projection. A fictitious object is arbitrarily defined that is constrained by such reference projection. The method modifies the known structure of the fictitious object by comparing and optimizing its four projections to those of the unknown structure of the real object and continues to iterate until the optimization is limited by the residual sum of background noise. The method is composed of several sub-processes that acquire four projections from the real data and the fictitious object: generate an arbitrary distribution to define the fictitious object, optimize the four projections, generate a new distribution for the fictitious object, and enhance the reconstructed image. The sub-process for the acquisition of the four projections from the input real data is simply the function of acquiring the four projections from the data of the transmitted intensity. The transmitted intensity represents the density distribution, that is, the distribution of absorption coefficients through the object.
Three dimensional SPH simulations of radiation-driven warped accretion discs
Stephen B. Foulkes; Carole A. Haswell; James R. Murray
2006-01-06T23:59:59.000Z
We present three dimensional smoothed particle hydrodynamics (SPH) calculations of warped accretion discs in X-ray binary systems. Geometrically thin, optically thick accretion discs are illuminated by a central radiation source. This illumination exerts a non-axisymmetric radiation pressure on the surface of the disc resulting in a torque that acts on the disc to induce a twist or warp. Initially planar discs are unstable to warping driven by the radiation torque and in general the warps also precess in a retrograde direction relative to the orbital flow. We simulate a number of X-ray binary systems which have different mass ratios using a number of different luminosities for each. Radiation-driven warping occurs for all systems simulated. For mass ratios q ~ 0.1 a moderate warp occurs in the inner disc while the outer disc remains in the orbital plane (c.f. X 1916-053). For less extreme mass ratios the entire disc tilts out of the orbital plane (c.f. Her X-1). For discs that are tilted out of the orbital plane in which the outer edge material of the disc is precessing in a prograde direction we obtain both positive and negative superhumps simultaneously in the dissipation light curve (c.f. V603 Aql).
Revealing the escape mechanism of three-dimensional orbits in a tidally limited star cluster
Euaggelos E. Zotos
2014-11-18T23:59:59.000Z
The aim of this work is to explore the escape process of three-dimensional orbits in a star cluster rotating around its parent galaxy in a circular orbit. The gravitational field of the cluster is represented by a smooth, spherically symmetric Plummer potential, while the tidal approximation was used to model the steady tidal field of the galaxy. We conduct a thorough numerical analysis distinguishing between regular and chaotic orbits as well as between trapped and escaping orbits, considering only unbounded motion for several energy levels. It is of particular interest to locate the escape basins towards the two exit channels and relate them with the corresponding escape times of the orbits. For this purpose, we split our investigation into three cases depending on the initial value of the $z$ coordinate which was used for launching the stars. The most noticeable finding is that the majority of stars initiated very close to the primary $(x,y)$ plane move in chaotic orbits and they remain trapped for vast time intervals, while orbits with relatively high values of $z_0$ on the other hand, form well-defined basins of escape. It was also observed, that for energy levels close to the critical escape energy the escape rates of orbits are large, while for much higher values of energy most of the orbits have low escape periods or they escape immediately to infinity. We hope our outcomes to be useful for a further understanding of the dissolution process and the escape mechanism in open star clusters.
THREE-DIMENSIONAL MAGNETOHYDRODYNAMIC MODELING OF PROPAGATING DISTURBANCES IN FAN-LIKE CORONAL LOOPS
Wang, Tongjiang; Ofman, Leon [Department of Physics, Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064 (United States)] [Department of Physics, Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064 (United States); Davila, Joseph M., E-mail: tongjiang.wang@nasa.gov [NASA Goddard Space Flight Center, Code 671, Greenbelt, MD 20770 (United States)
2013-09-20T23:59:59.000Z
Quasi-periodic propagating intensity disturbances (PDs) have been observed in large coronal loops in EUV images over a decade, and are widely accepted to be slow magnetosonic waves. However, spectroscopic observations from Hinode/EIS revealed their association with persistent coronal upflows, making this interpretation debatable. Motivated by the scenario that the coronal upflows could be the cumulative result of numerous individual flow pulses generated by sporadic heating events (nanoflares) at the loop base, we construct a velocity driver with repetitive tiny pulses, whose energy frequency distribution follows the flare power-law scaling. We then perform three-dimensional MHD modeling of an idealized bipolar active region by applying this broadband velocity driver at the footpoints of large coronal loops which appear open in the computational domain. Our model successfully reproduces the PDs with similar features as the observed, and shows that any upflow pulses inevitably excite slow magnetosonic wave disturbances propagating along the loop. We find that the generated PDs are dominated by the wave signature as their propagation speeds are consistent with the wave speed in the presence of flows, and the injected flows rapidly decelerate with height. Our simulation results suggest that the observed PDs and associated persistent upflows may be produced by small-scale impulsive heating events (nanoflares) at the loop base in the corona, and that the flows and waves may both contribute to the PDs at lower heights.
Stein, Joshua S. (Sandia National Laboratories, Carlsbad, NM); Rautman, Christopher Arthur
2004-02-01T23:59:59.000Z
The geologic model implicit in the original site characterization report for the Bayou Choctaw Strategic Petroleum Reserve Site near Baton Rouge, Louisiana, has been converted to a numerical, computer-based three-dimensional model. The original site characterization model was successfully converted with minimal modifications and use of new information. The geometries of the salt diapir, selected adjacent sedimentary horizons, and a number of faults have been modeled. Models of a partial set of the several storage caverns that have been solution-mined within the salt mass are also included. Collectively, the converted model appears to be a relatively realistic representation of the geology of the Bayou Choctaw site as known from existing data. A small number of geometric inconsistencies and other problems inherent in 2-D vs. 3-D modeling have been noted. Most of the major inconsistencies involve faults inferred from drill hole data only. Modem computer software allows visualization of the resulting site model and its component submodels with a degree of detail and flexibility that was not possible with conventional, two-dimensional and paper-based geologic maps and cross sections. The enhanced visualizations may be of particular value in conveying geologic concepts involved in the Bayou Choctaw Strategic Petroleum Reserve site to a lay audience. A Microsoft WindowsTM PC-based viewer and user-manipulable model files illustrating selected features of the converted model are included in this report.
Analysis and verification of a three-dimensional hydrodynamic numerical model
Abraham, David Daniel
1991-01-01T23:59:59.000Z
the partial differential equations to a solution of linear or non-linear algebraic equations through a finite element formulation is not all as simple as the shorthand notation of equations 25 and 27 might indicate. For a more complete discussion see... assembly. The induced D. C. voltages are detected by four electrodes. These voltages are processed by a signal conditioner into analog voltages. The analog voltage signal is linearly proportional to the x and y components of the velocity vector. A...
Turbulent flow and drag over fixed two-and three-dimensional dunes Jeremy G. Venditti1,2
Venditti, Jeremy G.
measurements of turbulent flow were obtained over a fixed flat bed, two- dimensional (2-D) dunes and four types over 2-D dunes conforms with previous observations of flow over mobile and fixed bed forms. Bed formTurbulent flow and drag over fixed two- and three-dimensional dunes Jeremy G. Venditti1,2 Received
Aickelin, Uwe
residential energy consumers in the UK by considering property energy efficiency levels, the greenness1 A Three-Dimensional Model of Residential Energy Consumer Archetypes for Local Energy Policy lines of research in residential energy consumption in the UK, i.e. economic/infrastructure, behaviour
California at Irvine, University of
-array photovoltaics on low-cost and flexible substrates Zhiyong Fan1,2,3 , Haleh Razavi1,2,3 , Jae-won Do1,2,3 , Aimee demonstrate a photovoltaic structure that incorpo- rates three-dimensional, single-crystalline n photovoltaics, may not be applicable for cost-effective solar modules, especially when compound semiconductors
Wijngaarden, Rinke J.
Extremal Dynamics and the Approach to the Critical State: Experiments on a Three Dimensional Pile in three dimensions. With time, the pile approaches a critical state with a certain slope. Assuming extremal dynamics in the evolution of the pile, the way the critical state is approached is dictated
cytometry, this can be achieved by focusing the cell solution at the centre of the flow tube horizontal (parallel to the device plane) sheath flows. One may readily fabricate the device for 2DSingle-layer planar on-chip flow cytometer using microfluidic drifting based three-dimensional (3D
Abbett, Bill
THE DYNAMIC EVOLUTION OF TWISTED MAGNETIC FLUX TUBES IN A THREE-DIMENSIONAL CONVECTING FLOW. I. UNIFORMLY BUOYANT HORIZONTAL TUBES Y. Fan High Altitude Observatory, National Center for Atmospheric-dimensional numerical simulations of the dynamic evolution of uniformly buoyant, twisted horizontal magnetic flux tubes
Three-Dimensional Reconnection of Untwisted Magnetic Flux M. G. Linton 1 and E. R. Priest 2
Priest, Eric
and Forbes, 2000). Reconnection probably plays an important role as an energy source for coronal heating (e in the immediate neighborhood of a reconnection region, which, at such small scales, is expected to be 2D. However, the manner in which these local reconnection regions connect to the larger scale, global, three dimensional
So, Peter
Quantitative Analysis of Three-Dimensional-Resolved Fiber Architecture in Heterogeneous Skeletal Muscle Tissue Using NMR and Optical Imaging Methods Vitaly J. Napadow,* Qun Chen, Vu Mai, Peter T. C. So Center and Harvard Medical School, Boston, Massachusetts ABSTRACT The determination of principal fiber
James, Stephen M.
2011-08-08T23:59:59.000Z
-dimensional axisymmetric beam-element code. ANSYS is used as a code to build three-dimensional non-axisymmetric solid-element casing models. The work done in this thesis opens the scope to incorporate complex non-axisymmetric casing models with XLTRC2....
James, Stephen M.
2011-08-08T23:59:59.000Z
The subject of this thesis is an extension of a two-dimensional, axisymmetric, Timoshenko-beam finite-element rotordynamic code to include a three-dimensional non-axisymmetric solid-element casing model. Axisymmetric beams are sufficient to model...
Kerr, H.G.; White, N. [Univ. of Cambridge (United Kingdom)
1996-03-01T23:59:59.000Z
A general, automatic method for determining the three-dimensional geometry of a normal fault of any shape and size is applied to a three-dimensional seismic reflection data set from the Nun River field, Nigeria. In addition to calculating fault geometry, the method also automatically retrieves the extension direction without requiring any previous information about either the fault shape or the extension direction. Solutions are found by minimizing the misfit between sets of faults that are calculated from the observed geometries of two or more hanging-wall beds. In the example discussed here, the predicted fault surface is in excellent agreement with the shape of the seismically imaged fault. Although the calculated extension direction is oblique to the average strike of the fault, the value of this parameter is not well resolved. Our approach differs markedly from standard section-balancing models in two important ways. First, we do not assume that the extension direction is known, and second, the use of inverse theory ensures that formal confidence bounds can be determined for calculated fault geometries. This ability has important implications for a range of geological problems encountered at both exploration and production scales. In particular, once the three-dimensional displacement field has been constrained, the difficult but important problem of three-dimensional palinspastic restoration of hanging-wall structures becomes tractable.
To appear in Proc. 48th IEEE CDC Three-Dimensional Motion Coordination in a Time-Invariant Flowfield
Shapiro, Benjamin
in the air [1] and sea [2]. For example, Areosonde unmanned aerial vehicles have flown into hurricanes-scale operating domain. However, motivated by unmanned vehicles that perform volumetric sampling-- such as underwater gliders and unmanned aircraft--we are interested in studying a three-dimensional model. For con
Wave EnergyFocusing in aThree-dimensional Numerical WaveTank C. Fochesato*, F. Dias**, S. Grilli***
Grilli, Stéphan T.
Wave EnergyFocusing in aThree-dimensional Numerical WaveTank C. Fochesato*, F. Dias**, S. Grilli Department (University of Rhode Island), Narragansett, RI, U.S.A. ABSTRACT Directional wave energy focusing in space is one of the mechanisms that may contribute to the generation of a rogue wave in the ocean
Kane, Charles
Surface states and topological invariants in three-dimensional topological insulators: Application Brillouin zone. This confirms that the alloy is a strong topological insulator in the 1;111 Z2 topological the surface states. We show that the sign of nM in the topological insulator phase of Bi1-xSbx is related
1302. P6.51. Using Real-Time Three-Dimensional Ultrasound To Characterize Mitral Valve Motion P results aim to fully characterize the four-dimensional (3D + time) movement of the mitral valve for better understanding of its behavior prior to surgical interventions, such as mitral valve repair. A behavior model
Fringer, Oliver B.
and the confluence of the SacramentoSan Joaquin Rivers and comprises San Pablo Bay, Suisun Bay and Central Bay and San Joaquin rivers, while high inflows result in enhanced salinity stratification and gravitationalSensitivity analysis of three-dimensional salinity simulations in North San Francisco Bay using
Three-Dimensional Analysis of Solid Oxide Fuel Cell Ni-YSZ Anode Interconnectivity James R. Wilson,a
Kalies, William D.
of interconnectivity of solid-oxide fuel cell (SOFC) electrode phases. The method was applied to the three1 Three-Dimensional Analysis of Solid Oxide Fuel Cell Ni-YSZ Anode Interconnectivity James R, and hence was not electrochemically active. #12;2 1. Introduction Attempts to understand solid oxide fuel
Ma, S.; Sun, D.; Forster, P. M.; Yuan, D.; Zhuang, W.; Chen, Y. S.; Parise, J. B.; Zhou, H. C. (Chemical Sciences and Engineering Division); (Texas A& M Univ.); (Univ. of Chicago); (Stony Brook Univ.)
2009-04-23T23:59:59.000Z
A three-dimensional porous metal-organic framework (PCN-18) was constructed through interdigitating two-dimensional grid sheets composed of 4,4{prime}-(anthracene-9,10-diyl)dibenzoate and copper paddlewheel secondary building units, and its dynamic features were evidenced by gas sorption isotherms.
Marques, Francisco
. INTRODUCTION Interest in natural convection in enclosures has a long history,1 motivated by both relevanceThree-dimensional instabilities in a discretely heated annular flow: Onset of spatio- temporal of the flow in an annular rotor-stator cavity Phys. Fluids 21, 064106 (2009); 10.1063/1.3156859 Stability
lysozyme in the complex were assigned by using a 15 N-edited three-dimensional nuclear
Miller, Webb
lysozyme in the complex were assigned by using a 15 N-edited three-dimensional nuclear O¨ verhauser. 9, 308315 (2002). 12. Schenk, D. Amyloid-beta immunotherapy for Alzheimer's disease: the end fibril formation in vitro. Biochemistry 31, 86548660 (1992). 18. Morozova-Roche, L. A. et al. Amyloid
Brown, Michael R.
Two fluid effects on three-dimensional reconnection in the Swarthmore Spheromak Experiment results are reported from spheromak merging studies at the Swarthmore Spheromak Experiment M. R. Brown in the plasma flows and heating . In this paper, we discuss three results from the Swarthmore Spheromak
century as in the 19th century. In this paper I use finite element analysis to address the question, how element analysis Tom Parsons U.S. Geological Survey, Menlo Park, California, USA Received 23 August 2001 area seismic hazard assessment. This study presents a three-dimensional (3-D) finite element simulation
Boyer, Edmond
is therefore needed. Therefore highly heterogeneous temperature fields and heat fluxes can be evaluating. Asymptotic developments enable to take into account variations of thermal properties depending on temperatureInverse three-dimensional method for fast evaluation of temperature and heat flux fields during
Fialko, Yuri
Three-dimensional deformation caused by the Bam, Iran, earthquake and the origin of shallow slip (Iran) earth- quake using radar data from the Envisat satellite of the European Space Agency. Analysis. In this paper we report on deformation associated with the Mw6.5 Bam (Iran) earthquake determined using
Boyer, Edmond
- 1 - Implementation of surface tension with wall adhesion effects in a three-dimensional finite element modelling of surface tension. The external stress vectors associated with surface tension a drop of liquid on a plane is treated. Keywords : surface tension, finite element method, average
THREE-DIMENSIONAL ATMOSPHERIC CIRCULATION OF HOT JUPITERS ON HIGHLY ECCENTRIC ORBITS
Kataria, T.; Showman, A. P.; Lewis, N. K. [Department of Planetary Sciences and Lunar and Planetary Laboratory, The University of Arizona, Tucson, AZ 85721 (United States)] [Department of Planetary Sciences and Lunar and Planetary Laboratory, The University of Arizona, Tucson, AZ 85721 (United States); Fortney, J. J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)] [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Marley, M. S.; Freedman, R. S., E-mail: tkataria@lpl.arizona.edu [NASA Ames Research Center 245-3, Moffett Field, CA 94035 (United States)
2013-04-10T23:59:59.000Z
Of the over 800 exoplanets detected to date, over half are on non-circular orbits, with eccentricities as high as 0.93. Such orbits lead to time-variable stellar heating, which has major implications for the planet's atmospheric dynamical regime. However, little is known about the fundamental dynamical regime of such planetary atmospheres, and how it may influence the observations of these planets. Therefore, we present a systematic study of hot Jupiters on highly eccentric orbits using the SPARC/MITgcm, a model which couples a three-dimensional general circulation model (the MITgcm) with a plane-parallel, two-stream, non-gray radiative transfer model. In our study, we vary the eccentricity and orbit-average stellar flux over a wide range. We demonstrate that the eccentric hot Jupiter regime is qualitatively similar to that of planets on circular orbits; the planets possess a superrotating equatorial jet and exhibit large day-night temperature variations. As in Showman and Polvani, we show that the day-night heating variations induce momentum fluxes equatorward to maintain the superrotating jet throughout its orbit. We find that as the eccentricity and/or stellar flux is increased (corresponding to shorter orbital periods), the superrotating jet strengthens and narrows, due to a smaller Rossby deformation radius. For a select number of model integrations, we generate full-orbit light curves and find that the timing of transit and secondary eclipse viewed from Earth with respect to periapse and apoapse can greatly affect what we see in infrared (IR) light curves; the peak in IR flux can lead or lag secondary eclipse depending on the geometry. For those planets that have large temperature differences from dayside to nightside and rapid rotation rates, we find that the light curves can exhibit 'ringing' as the planet's hottest region rotates in and out of view from Earth. These results can be used to explain future observations of eccentric transiting exoplanets.
GENERAL-RELATIVISTIC SIMULATIONS OF THREE-DIMENSIONAL CORE-COLLAPSE SUPERNOVAE
Ott, Christian D.; Abdikamalov, Ernazar; Moesta, Philipp; Haas, Roland; Drasco, Steve; O'Connor, Evan P.; Reisswig, Christian [TAPIR, Mailcode 350-17, California Institute of Technology, Pasadena, CA 91125 (United States); Meakin, Casey A. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM (United States); Schnetter, Erik, E-mail: cott@tapir.caltech.edu [Perimeter Institute for Theoretical Physics, Waterloo, ON (Canada)
2013-05-10T23:59:59.000Z
We study the three-dimensional (3D) hydrodynamics of the post-core-bounce phase of the collapse of a 27 M{sub Sun} star and pay special attention to the development of the standing accretion shock instability (SASI) and neutrino-driven convection. To this end, we perform 3D general-relativistic simulations with a three-species neutrino leakage scheme. The leakage scheme captures the essential aspects of neutrino cooling, heating, and lepton number exchange as predicted by radiation-hydrodynamics simulations. The 27 M{sub Sun} progenitor was studied in 2D by Mueller et al., who observed strong growth of the SASI while neutrino-driven convection was suppressed. In our 3D simulations, neutrino-driven convection grows from numerical perturbations imposed by our Cartesian grid. It becomes the dominant instability and leads to large-scale non-oscillatory deformations of the shock front. These will result in strongly aspherical explosions without the need for large-scale SASI shock oscillations. Low-l-mode SASI oscillations are present in our models, but saturate at small amplitudes that decrease with increasing neutrino heating and vigor of convection. Our results, in agreement with simpler 3D Newtonian simulations, suggest that once neutrino-driven convection is started, it is likely to become the dominant instability in 3D. Whether it is the primary instability after bounce will ultimately depend on the physical seed perturbations present in the cores of massive stars. The gravitational wave signal, which we extract and analyze for the first time from 3D general-relativistic models, will serve as an observational probe of the postbounce dynamics and, in combination with neutrinos, may allow us to determine the primary hydrodynamic instability.
Frederick, B.deB. [California Univ., Berkeley, CA (United States)]|[Lawrence Berkeley Lab., CA (United States)
1994-12-01T23:59:59.000Z
Nuclear magnetic resonance (NMR) spectroscopic imaging of {sup 23}Na holds promise as a non-invasive method of mapping Na{sup +} distributions, and for differentiating pools of Na{sup +} ions in biological tissues. However, due to NMR relaxation properties of {sup 23}Na in vivo, a large fraction of Na{sup +} is not visible with conventional NMR imaging methods. An alternate imaging method, based on stochastic excitation and oscillating gradients, has been developed which is well adapted to measuring nuclei with short T{sub 2}. Contemporary NMR imaging techniques have dead times of up to several hundred microseconds between excitation and sampling, comparable to the shortest in vivo {sup 23}Na T{sub 2} values, causing significant signal loss. An imaging strategy based on stochastic excitation has been developed which greatly reduces experiment dead time by reducing peak radiofrequency (RF) excitation power and using a novel RF circuit to speed probe recovery. Continuously oscillating gradients are used to eliminate transient eddy currents. Stochastic {sup 1}H and {sup 23}Na spectroscopic imaging experiments have been performed on a small animal system with dead times as low as 25{mu}s, permitting spectroscopic imaging with 100% visibility in vivo. As an additional benefit, the encoding time for a 32x32x32 spectroscopic image is under 30 seconds. The development and analysis of stochastic NMR imaging has been hampered by limitations of the existing phase demodulation reconstruction technique. Three dimensional imaging was impractical due to reconstruction time, and design and analysis of proposed experiments was limited by the mathematical intractability of the reconstruction method. A new reconstruction method for stochastic NMR based on Fourier interpolation has been formulated combining the advantage of a several hundredfold reduction in reconstruction time with a straightforward mathematical form.
Three-dimensional braid-plain architecture, Bulgo Formation, Sydney basin, Australia
Reynolds, S.A.; Glasford, J.L.
1989-03-01T23:59:59.000Z
The Triassic Bulgo Formation of the Sydney basin was deposited by a basin-wide braid-plain system. Detailed outcrop analysis of facies relationships and correlation with subsurface data allow for recognition of three-dimensional facies architecture and paleogeography reconstruction. The Lachlan foldbelt was the primary source for the Bulgo Formation. Three outcrop sites in varying proximity to the source area were examined: (1) Blue Mountains, (2) Burragorrang Walls, and (3) Royal National Park. Proximal deposits of the Blue Mountains consist of two members. Both the lower and upper Bulgo are coarse-grained, tabular sandstone sheets. They are separated by a paleosoil horizon which is the only criterion for separation. Medial deposits at Burrangorang Walls can be distinguished on the basis of shale content. The lower Bulgo remains a coarse-grained, tabular sandstone sheet. The upper Bulgo is also a coarse-grained, tabular sandstone sheet. The upper Bulgo is also a coarse-grained, tabular sandstone sheet. The upper Bulgo is also a coarse-grained sandstone sheet but contains a significant proportion of interchannel shale deposits and mud plugs. Distal deposits of the Royal National Park are characterized by a similar coarse-grained lower member which was deposited by a large braid-plain system where smaller braided systems coalesced into a basin-wide tabular sandstone sheet. However, the upper Bulgo member shows a further downdip evolution to a fine-grained sandstone sheet deposited by small, interconnected braided streams which were separated by numerous flood-plain and paludal deposits. This upsection and lateral evolution reflects waning sediment supply and denudation of the Lachlan foldbelt source area.
Yoshimatsu, Katsunori; Kawahara, Yasuhiro [Department of Computational Science and Engineering, Nagoya University, Nagoya 464-8603 (Japan); Schneider, Kai [M2P2-CNRS and CMI, Universite de Provence, 39 rue Frederic Joliot-Curie, 13453 Marseille Cedex 13 (France); Okamoto, Naoya [Center for Computational Science, Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan); Farge, Marie [LMD-IPSL-CNRS, Ecole Normale Superieure, 24 rue Lhomond, 75231 Paris Cedex 05 (France)
2011-09-15T23:59:59.000Z
Scale-dependent and geometrical statistics of three-dimensional incompressible homogeneous magnetohydrodynamic turbulence without mean magnetic field are examined by means of the orthogonal wavelet decomposition. The flow is computed by direct numerical simulation with a Fourier spectral method at resolution 512{sup 3} and a unit magnetic Prandtl number. Scale-dependent second and higher order statistics of the velocity and magnetic fields allow to quantify their intermittency in terms of spatial fluctuations of the energy spectra, the flatness, and the probability distribution functions at different scales. Different scale-dependent relative helicities, e.g., kinetic, cross, and magnetic relative helicities, yield geometrical information on alignment between the different scale-dependent fields. At each scale, the alignment between the velocity and magnetic field is found to be more pronounced than the other alignments considered here, i.e., the scale-dependent alignment between the velocity and vorticity, the scale-dependent alignment between the magnetic field and its vector potential, and the scale-dependent alignment between the magnetic field and the current density. Finally, statistical scale-dependent analyses of both Eulerian and Lagrangian accelerations and the corresponding time-derivatives of the magnetic field are performed. It is found that the Lagrangian acceleration does not exhibit substantially stronger intermittency compared to the Eulerian acceleration, in contrast to hydrodynamic turbulence where the Lagrangian acceleration shows much stronger intermittency than the Eulerian acceleration. The Eulerian time-derivative of the magnetic field is more intermittent than the Lagrangian time-derivative of the magnetic field.
Testa, Paola [Smithsonian Astrophysical Observatory, 60 Garden Street, MS 58, Cambridge, MA 02138 (United States); De Pontieu, Bart; Martinez-Sykora, Juan [Lockheed Martin Solar and Astrophysics Laboratory, Org. A021S, Building 252, 3251 Hanover Street, Palo Alto, CA 94304 (United States); Hansteen, Viggo; Carlsson, Mats, E-mail: ptesta@cfa.harvard.edu [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029, Blindern, NO-0315 Oslo (Norway)
2012-10-10T23:59:59.000Z
Determining the temperature distribution of coronal plasmas can provide stringent constraints on coronal heating. Current observations with the Extreme ultraviolet Imaging Spectrograph (EIS) on board Hinode and the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory provide diagnostics of the emission measure distribution (EMD) of the coronal plasma. Here we test the reliability of temperature diagnostics using three-dimensional radiative MHD simulations. We produce synthetic observables from the models and apply the Monte Carlo Markov chain EMD diagnostic. By comparing the derived EMDs with the 'true' distributions from the model, we assess the limitations of the diagnostics as a function of the plasma parameters and the signal-to-noise ratio of the data. We find that EMDs derived from EIS synthetic data reproduce some general characteristics of the true distributions, but usually show differences from the true EMDs that are much larger than the estimated uncertainties suggest, especially when structures with significantly different density overlap along the line of sight. When using AIA synthetic data the derived EMDs reproduce the true EMDs much less accurately, especially for broad EMDs. The differences between the two instruments are due to the: (1) smaller number of constraints provided by AIA data and (2) broad temperature response function of the AIA channels which provide looser constraints to the temperature distribution. Our results suggest that EMDs derived from current observatories may often show significant discrepancies from the true EMDs, rendering their interpretation fraught with uncertainty. These inherent limitations to the method should be carefully considered when using these distributions to constrain coronal heating.
High-resolution three-dimensional simulations of core-collapse supernovae in multiple progenitors
Couch, Sean M. [Flash Center for Computational Science, Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); O'Connor, Evan P., E-mail: smc@flash.uchicago.edu [Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, Ontario M5S 3H8 (Canada)
2014-04-20T23:59:59.000Z
Three-dimensional (3D) simulations of core-collapse supernovae (CCSNe) are granting new insight into the as-yet-uncertain mechanism that drives successful explosions. While there is still debate about whether explosions are obtained more easily in 3D than in 2D, it is undeniable that there exist qualitative and quantitative differences between the results of 3D and 2D simulations. We present an extensive set of high-resolution 1D, 2D, and 3D CCSN simulations with multispecies neutrino leakage carried out in two different progenitors. Our simulations confirm the results of Couch indicating that 2D explodes more readily than 3D. We argue that this is due to the inadequacies of 2D to accurately capture important aspects of the 3D dynamics. We find that without artificially enhancing the neutrino heating rate, we do not obtain explosions in 3D. We examine the development of neutrino-driven convection and the standing accretion shock instability (SASI) and find that, in separate regimes, either instability can dominate. We find evidence for growth of the SASI for both 15 M {sub ?} and 27 M {sub ?} progenitors; however, it is weaker in 3D exploding models. The growth rate of both instabilities is artificially enhanced along the symmetry axis in 2D as compared with our axis-free 3D Cartesian simulations. Our work highlights the growing consensus that CCSNe must be studied in 3D if we hope to solve the mystery of how the explosions are powered.
Equilibrium vortex motion in two- and three-dimensional superconductors studied with a dc SQUID
Shaw, T.J. [Univ. of California, Berkeley, CA (United States). Dept. of Physics]|[Lawrence Berkeley National Lab., CA (United States). Materials Sciences Div.
1997-10-01T23:59:59.000Z
The equilibrium motion of vortices in two- and three-dimensional superconductors has been studied with a dc Superconducting QUantum Interference Device (SQUID). This technique has the advantage of probing the system in a non-invasive manner as well as providing dynamic information over many decades in frequency. Through measurements of the spectral density of magnetic flux noise, S{sub {Phi}}({omega}), as a function of temperature and applied magnetic field, the effects of proton and heavy ion irradiation on flux noise in crystals of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} have been measured and compared with the effects on the critical current, J{sub c}. Both proton and heavy ion irradiation proved effective at reducing S{sub {Phi}}({omega}), with proton irradiation having a larger effect. Measurement of S{sub {Phi}}({omega}) due to the equilibrium Kosterlitz-Thouless-Berezinskii transition in two-dimensional Josephson Junction Arrays (JJAs) was studied as a function of temperature for three different arrays and using three different sensors. S{sub {Phi}} is shown to obey dynamic scaling over as many as five decades in frequency, and estimates are made for the dynamic critical exponent z. An analytic theory for the high- and low-frequency behavior of S{sub {Phi}}({omega}) is presented and compared to the measured data, with the result that the low-frequency behavior is well described by the theory but the high-frequency behavior is not. Other theories and numerical simulations are described and compared with the data, but none are completely satisfactory. Lastly, suggestions for necessary further theoretical work and possible future experimental work are suggested.
New techniques for the scientific visualization of three-dimensional multi-variate and vector fields
Crawfis, R.A.
1995-10-01T23:59:59.000Z
Volume rendering allows us to represent a density cloud with ideal properties (single scattering, no self-shadowing, etc.). Scientific visualization utilizes this technique by mapping an abstract variable or property in a computer simulation to a synthetic density cloud. This thesis extends volume rendering from its limitation of isotropic density clouds to anisotropic and/or noisy density clouds. Design aspects of these techniques are discussed that aid in the comprehension of scientific information. Anisotropic volume rendering is used to represent vector based quantities in scientific visualization. Velocity and vorticity in a fluid flow, electric and magnetic waves in an electromagnetic simulation, and blood flow within the body are examples of vector based information within a computer simulation or gathered from instrumentation. Understand these fields can be crucial to understanding the overall physics or physiology. Three techniques for representing three-dimensional vector fields are presented: Line Bundles, Textured Splats and Hair Splats. These techniques are aimed at providing a high-level (qualitative) overview of the flows, offering the user a substantial amount of information with a single image or animation. Non-homogenous volume rendering is used to represent multiple variables. Computer simulations can typically have over thirty variables, which describe properties whose understanding are useful to the scientist. Trying to understand each of these separately can be time consuming. Trying to understand any cause and effect relationships between different variables can be impossible. NoiseSplats is introduced to represent two or more properties in a single volume rendering of the data. This technique is also aimed at providing a qualitative overview of the flows.
FORMATION AND RECONNECTION OF THREE-DIMENSIONAL CURRENT SHEETS IN THE SOLAR CORONA
Edmondson, J. K. [NASA Jet Propulsion Laboratory, Pasadena, CA 91109 (United States); Antiochos, S. K. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); DeVore, C. R. [Naval Research Laboratory, Washington, DC 20375 (United States); Zurbuchen, T. H., E-mail: jkedmond@umich.ed [Department of Atmospheric, Oceanic, and Space Science, University of Michigan, Ann Arbor, MI 48105 (United States)
2010-07-20T23:59:59.000Z
Current-sheet formation and magnetic reconnection are believed to be the basic physical processes responsible for much of the activity observed in astrophysical plasmas, such as the Sun's corona. We investigate these processes for a magnetic configuration consisting of a uniform background field and an embedded line dipole, a topology that is expected to be ubiquitous in the corona. This magnetic system is driven by a uniform horizontal flow applied at the line-tied photosphere. Although both the initial field and the driver are translationally symmetric, the resulting evolution is calculated using a fully three-dimensional (3D) magnetohydrodynamic simulation with adaptive mesh refinement that resolves the current sheet and reconnection dynamics in detail. The advantage of our approach is that it allows us to directly apply the vast body of knowledge gained from the many studies of two-dimensional (2D) reconnection to the fully 3D case. We find that a current sheet forms in close analogy to the classic Syrovatskii 2D mechanism, but the resulting evolution is different than expected. The current sheet is globally stable, showing no evidence for a disruption or a secondary instability even for aspect ratios as high as 80:1. The global evolution generally follows the standard Sweet-Parker 2D reconnection model except for an accelerated reconnection rate at a very thin current sheet, due to the tearing instability and the formation of magnetic islands. An interesting conclusion is that despite the formation of fully 3D structures at small scales, the system remains close to 2D at global scales. We discuss the implications of our results for observations of the solar corona.
A THREE-DIMENSIONAL VIEW OF THE REMNANT OF NOVA PERSEI 1901 (GK Per)
Liimets, T.; Verro, K.; Kolka, I. [Tartu Observatory, 61602 Toravere (Estonia); Corradi, R. L. M.; Rodriguez-Gil, P. [Instituto de Astrofisica de Canarias, Via Lactea s/n, E-38205 La Laguna, Santa Cruz de Tenerife (Spain); Santander-Garcia, M. [Observatorio Astronomico Nacional, Ap. de Correos 112, E-28803 Alcala de Henares, Madrid (Spain); Villaver, E. [Departamento de Fisica Teorica, Universidad Autonoma de Madrid, E-28049 Madrid (Spain)
2012-12-10T23:59:59.000Z
We present a kinematical study of the optical ejecta of GK Per. It is based on proper-motion measurements of 282 knots from {approx}20 images spanning 25 years. Doppler shifts are also computed for 217 knots. The combination of proper motions and radial velocities allows a unique three-dimensional view of the ejecta to be obtained. The main results are as follows: (1) the outflow is a thick shell in which knots expand with a significant range of velocities, mostly between 600 and 1000 km s{sup -1}, (2) kinematical ages indicate that knots have suffered only a modest deceleration since their ejection a century ago, (3) no evidence for anisotropy in the expansion rate is found, (4) velocity vectors are generally aligned along the radial direction, but a symmetric pattern of non-radial velocities is also observed at specific directions, and (5) the total H{alpha}+[N II] flux has been linearly decreasing at a rate of 2.6% per year in the past decade. The eastern nebular side is fading at a slower rate than the western side. Some of the knots were displayed a rapid change of brightness during the 2004-2011 period. Over a longer timescale, a progressive circularization and homogenization of the nebula are taking place; (6) a kinematic distance of 400 {+-} 30 pc is determined. These results raise some problems with the previous interpretations of the evolution of GK Per. In particular, the idea of a strong interaction of the outflow with the surrounding medium in the southwest quadrant is not supported by our data.
SASI ACTIVITY IN THREE-DIMENSIONAL NEUTRINO-HYDRODYNAMICS SIMULATIONS OF SUPERNOVA CORES
Hanke, Florian; Mueller, Bernhard; Wongwathanarat, Annop; Marek, Andreas; Janka, Hans-Thomas, E-mail: fhanke@mpa-garching.mpg.de, E-mail: bjmuellr@mpa-garching.mpg.de, E-mail: annop@mpa-garching.mpg.de, E-mail: amarek@mpa-garching.mpg.de, E-mail: thj@mpa-garching.mpg.de [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany)
2013-06-10T23:59:59.000Z
The relevance of the standing accretion shock instability (SASI) compared to neutrino-driven convection in three-dimensional (3D) supernova-core environments is still highly controversial. Studying a 27 M{sub Sun} progenitor, we demonstrate, for the first time, that violent SASI activity can develop in 3D simulations with detailed neutrino transport despite the presence of convection. This result was obtained with the PROMETHEUS-VERTEX code with the same sophisticated neutrino treatment so far used only in one-dimensional and two-dimensional (2D) models. While buoyant plumes initially determine the nonradial mass motions in the postshock layer, bipolar shock sloshing with growing amplitude sets in during a phase of shock retraction and turns into a violent spiral mode whose growth is only quenched when the infall of the Si/SiO interface leads to strong shock expansion in response to a dramatic decrease of the mass accretion rate. In the phase of large-amplitude SASI sloshing and spiral motions, the postshock layer exhibits nonradial deformation dominated by the lowest-order spherical harmonics (l = 1, m = 0, {+-}1) in distinct contrast to the higher multipole structures associated with neutrino-driven convection. We find that the SASI amplitudes, shock asymmetry, and nonradial kinetic energy in three dimensions can exceed those of the corresponding 2D case during extended periods of the evolution. We also perform parameterized 3D simulations of a 25 M{sub Sun} progenitor, using a simplified, gray neutrino transport scheme, an axis-free Yin-Yang grid, and different amplitudes of random seed perturbations. They confirm the importance of the SASI for another progenitor, its independence of the choice of spherical grid, and its preferred growth for fast accretion flows connected to small shock radii and compact proto-neutron stars as previously found in 2D setups.
Laplace Transforms An integral transform is an operator
Ikenaga, Bruce
9281998 Laplace Transforms An integral transform is an operator F (s) = Z b a K(s; t)f(t) dt: The input to the transform is the function f(t); the output is the function F (s). (By convention, small letters denote the inputs to a transform, and the corresponding capital letters denote the corresponding
FROM NO"RLUND MATRICES TO LAPLACE REPRESENTATIONS
Sinnamon, Gordon J.
(and not * *too large) on the line Re z = 0, the Laplace transform LF is just the (Poisson exte* *nsion of the) Fourier transform of F . It is therefore appropriate to view the power * *series. Analogous inequalities are proved for power series representations * *of functions in weighted Hardy
A three-dimensional coupled modes solution for range-dependent waveguides
Luo, Wenyu
2005-01-01T23:59:59.000Z
Despite the great achievements obtained with fast-field and parabolic equation models, normal mode programs still remain a very efficient, simple and practical tool for describing ocean acoustics in range-independent ...
A finite element model of the quasi-three-dimensional viscous flow through airfoil cascades
McArthur, Dwight Roger
1987-01-01T23:59:59.000Z
equation: 1 cl OVs ? ? (rbV, ) + ? = 0 b Bs 88 (4) s ? momentum equation: 1 s Op OV, gV, OVs +ozp+og ~ + s +o4V +usVsyos +ng (5) Re ' Os Bs where: 1 db 1 dr &1 ? + b ds r ds (5u) 1 f 1 dr 1 db't /' 5 ds) (55) Vs (5c) 1 fld2r 1 drdb 1 /dbms 1d...
Maier, Andreas; Wigstroem, Lars; Hofmann, Hannes G.; Hornegger, Joachim; Zhu Lei; Strobel, Norbert; Fahrig, Rebecca [Department of Radiology, Stanford University, Stanford, California 94305 (United States); Department of Radiology, Stanford University, Stanford, California 94305 (United States) and Center for Medical Image Science and Visualization, Linkoeping University, Linkoeping (Sweden); Pattern Recognition Laboratory, Department of Computer Science, Friedrich-Alexander University of Erlangen-Nuremberg, 91054, Erlangen (Germany); Nuclear and Radiological Engineering and Medical Physics Programs, George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Siemens AG Healthcare, Forchheim 91301 (Germany); Department of Radiology, Stanford University, Stanford, California 94305 (United States)
2011-11-15T23:59:59.000Z
Purpose: The combination of quickly rotating C-arm gantry with digital flat panel has enabled the acquisition of three-dimensional data (3D) in the interventional suite. However, image quality is still somewhat limited since the hardware has not been optimized for CT imaging. Adaptive anisotropic filtering has the ability to improve image quality by reducing the noise level and therewith the radiation dose without introducing noticeable blurring. By applying the filtering prior to 3D reconstruction, noise-induced streak artifacts are reduced as compared to processing in the image domain. Methods: 3D anisotropic adaptive filtering was used to process an ensemble of 2D x-ray views acquired along a circular trajectory around an object. After arranging the input data into a 3D space (2D projections + angle), the orientation of structures was estimated using a set of differently oriented filters. The resulting tensor representation of local orientation was utilized to control the anisotropic filtering. Low-pass filtering is applied only along structures to maintain high spatial frequency components perpendicular to these. The evaluation of the proposed algorithm includes numerical simulations, phantom experiments, and in-vivo data which were acquired using an AXIOM Artis dTA C-arm system (Siemens AG, Healthcare Sector, Forchheim, Germany). Spatial resolution and noise levels were compared with and without adaptive filtering. A human observer study was carried out to evaluate low-contrast detectability. Results: The adaptive anisotropic filtering algorithm was found to significantly improve low-contrast detectability by reducing the noise level by half (reduction of the standard deviation in certain areas from 74 to 30 HU). Virtually no degradation of high contrast spatial resolution was observed in the modulation transfer function (MTF) analysis. Although the algorithm is computationally intensive, hardware acceleration using Nvidia's CUDA Interface provided an 8.9-fold speed-up of the processing (from 1336 to 150 s). Conclusions: Adaptive anisotropic filtering has the potential to substantially improve image quality and/or reduce the radiation dose required for obtaining 3D image data using cone beam CT.
Three-dimensional x-ray fluorescence mapping of a gold nanoparticle-loaded phantom
Ren, Liqiang; Wu, Di; Li, Yuhua; Liu, Hong, E-mail: liu@ou.edu [Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States)] [Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States); Wang, Ge [Biomedical Imaging Cluster and Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)] [Biomedical Imaging Cluster and Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Wu, Xizeng [Department of Radiology, University of Alabama, Birmingham, Alabama 35233 (United States)] [Department of Radiology, University of Alabama, Birmingham, Alabama 35233 (United States)
2014-03-15T23:59:59.000Z
Purpose : X-ray fluorescence (XRF) is a promising technique with sufficient specificity and sensitivity for identifying and quantifying features in small samples containing high atomic number (Z) materials such as iodine, gadolinium, and gold. In this study, the feasibility of applying XRF to early breast cancer diagnosis and treatment is studied using a novel approach for three-dimensional (3D) x-ray fluorescence mapping (XFM) of gold nanoparticle (GNP)-loaded objects in a physical phantom at the technical level. Methods : All the theoretical analysis and experiments are conducted under the condition of using x-ray pencil beam and a compactly integrated x-ray spectrometer. The penetrability of the fluorescence x-rays from GNPs is first investigated by adopting a combination of BR12 with 70 mm/50 mm in thickness on the excitation/emission path to mimic the possible position of tumor goldin vivo. Then, a physical phantom made of BR12 is designed to translate in 3D space with three precise linear stages and subsequently the step by step XFM scanning is performed. The experimental technique named as background subtraction is applied to isolate the gold fluorescence from each spectrum obtained by the spectrometer. Afterwards, the attenuations of both the incident primary x-ray beam with energies beyond the gold K-edge energy (80.725 keV) and the isolated gold K{sub ?} fluorescence x-rays (65.99 –69.80 keV) acquired after background subtraction are well calibrated, and finally the unattenuated K{sub ?} fluorescence counts are used to realize mapping reconstruction and to describe the linear relationship between gold fluorescence counts and corresponding concentration of gold solutions. Results : The penetration results show that the goldK{sub ?} fluorescence x-rays have sufficient penetrability for this phantom study, and the reconstructed mapping results indicate that both the spatial distribution and relative concentration of GNPs within the designed BR12 phantom can be well identified and quantified. Conclusions : Although the XFM method in this investigation is still studied at the technical level and is not yet practical for routinein vivo mapping tasks with GNPs, the current penetrability measurements and phantom study strongly suggest the feasibility to establish and develop a 3D XFM system.
John T. Conway; Howard S. Cohl
2009-10-07T23:59:59.000Z
A new method is presented for Fourier decomposition of the Helmholtz Green Function in cylindrical coordinates, which is equivalent to obtaining the solution of the Helmholtz equation for a general ring source. The Fourier coefficients of the Helmholtz Green function are split into their half advanced+half retarded and half advanced-half retarded components. Closed form solutions are given for these components in terms of a Horn function and a Kampe de Feriet function, respectively. The systems of partial differential equations associated with these two-dimensional hypergeometric functions are used to construct a fourth-order ordinary differential equation which both components satisfy. A second fourth-order ordinary differential equation for the general Fourier coefficent is derived from an integral representation of the coefficient, and both differential equations are shown to be equivalent. Series solutions for the various Fourier coefficients are also given, mostly in terms of Legendre functions and Bessel/Hankel functions. These are derived from the closed form hypergeometric solutions or an integral representation, or both. Numerical calculations comparing different methods of calculating the Fourier coefficients are presented.
Villone, F. [Ass. Euratom/ENEA/CREATE, DAEIMI, Universita di Cassino, Via Di Biasio 43, 03043, Cassino (Italy); Liu, Y. Q. [EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Paccagnella, R.; Bolzonella, T. [Consorzio RFX, Ass. Euratom/ENEA, and C.N.R., Corso Stati Uniti 4, 35127, Padova (Italy); Rubinacci, G. [Ass. Euratom/ENEA/CREATE, DIEL, Universita di Napoli Federico II, Via Claudio 21, 80125, Napoli (Italy)
2008-06-27T23:59:59.000Z
In this Letter, the linear stability of the resistive wall modes (RWMs) in toroidal geometry for a reversed field pinch (RFP) plasma is studied. Three computational models are used: the cylindrical code ETAW, the toroidal MHD code MARS-F, and the CarMa code, able to take fully into account the effects of a three-dimensional conducting structure which mimics the real shell geometry of a reversed field pinch experimental device. The computed mode growth rates generally agree with experimental data. The toroidal effects and the three-dimensional features of the shell, like gaps, allow a novel interpretation of the RWM spectrum in RFP's and remove its degeneracy. This shows the importance of making accurate modeling of conductors for the RWM predictions also in future devices such as ITER.
W. Steven Holbrook
2004-11-11T23:59:59.000Z
This report contains a summary of work conducted and results produced under the auspices of award DE-FC26-00NT40921, ''DOE Three-Dimensional Structure and Physical Properties of a Methane Hydrate Deposit and Gas Reservoir, Blake Ridge.'' This award supported acquisition, processing, and interpretation of two- and three-dimensional seismic reflection data over a large methane hydrate reservoir on the Blake Ridge, offshore South Carolina. The work supported by this project has led to important new conclusions regarding (1) the use of seismic reflection data to directly detect methane hydrate, (2) the migration and possible escape of free gas through the hydrate stability zone, and (3) the mechanical controls on the maximum thickness of the free gas zone and gas escape.
Darmadi, Yan
2007-04-25T23:59:59.000Z
THREE-DIMENSIONAL FLUVIAL-DELTAIC SEQUENCE STRATIGRAPHY PLIOCENE-RECENT MUDA FORMATION, BELIDA FIELD, WEST NATUNA BASIN, INDONESIA A Thesis by YAN DARMADI Submitted to the Office of Graduate Studies of Texas A&M University..., WEST NATUNA BASIN, INDONESIA A Thesis by YAN DARMADI 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 Approved by: Chair...
L e t t e r A two-fold interpenetrated three-dimensional cobalt(II) complex with
Gao, Song
; it consists of two-fold interpenetrated a-Po- like networks. The study of inorganic coordination polymersL e t t e r A two-fold interpenetrated three-dimensional cobalt(II) complex with dual dicyanamide(II) coordination polymer, Co(4,4º- was constructed using dicyanamide and 4,4º-bpy)[N(CN) 2 ] 2 , bipyridine bridges
Grilli, StÃ©phan T.
Numerical Analysis of the Internal Kinematics and Dynamics of Three-dimensional Breaking Waves/Navier-Stokes solver. Analysis of wave profiles and kinematics (velocity, vorticity, pressure) are carried out. Keyword the breaking and post-breaking in a three- dimensional numerical wave tank of a solitary wave over a sloping
Cao, Guozhong
-5 The anatase TiO2 has become a highly promising anode material for LIBs. The titanium dioxide offers a greatDesign and Tailoring of a Three-Dimensional TiO2-Graphene- Carbon Nanotube Nanocomposite for Fast a three- dimensional (3D) hierarchical structure for fast lithium storage. CNTs in the unique hybrid
Juanjuan, Y.
1991-01-01T23:59:59.000Z
The interpretation of three-dimensional seismic data in Nanyishan structure area was finished in the following steps: 1. Seismic horizons are correlated with geological horizons by analyzing drilling data and various logging curves. 2. Seismic horizon picking and time structure map were achieved by using Apollo workstation's SEISTAR interpretation software package which can correlate vertical section with time slice. 3. Three-dimensional velocity data volume was made by performing various corrections of available sonic logging curves in the area. 4. Average velocity map for seismic horizon interpretation was plotted by using the three-dimensional velocity data volume and time structure map. 5. Depth structure map was drawn by making necessary mathematical operation of data files about time structure map and average velocity map with the use of corresponding module of Apollo workstation's MAPSTAR software package. The comprehensive analysis of drilling and seismic informations shows that the rich hydrocarbon seismic horizons in the Nanyishan structure are mainly characterized by low frequency, low velocity and high energy. So, the distributions of rich hydrocarbon reservoirs in top Oligocene (E{sub 3}) and mid pliocene (N{sub 2}) series were ascertained by using the seismic characteristics.
THREE DIMENSIONAL INTEGRATED CHARACTERIZATION AND ARCHIVING SYSTEM (3D-ICAS)
George Jarvis
2001-06-18T23:59:59.000Z
The overall objective of this project is to develop an integrated system that remotely characterizes, maps, and archives measurement data of hazardous decontamination and decommissioning (D&D) areas. The system will generate a detailed 3-dimensional topography of the area as well as real-time quantitative measurements of volatile organics and radionuclides. The system will analyze substrate materials consisting of concrete, asbestos, and transite. The system will permanently archive the data measurements for regulatory and data integrity documentation. Exposure limits, rest breaks, and donning and removal of protective garments generate waste in the form of contaminated protective garments and equipment. Survey times are increased and handling and transporting potentially hazardous materials incur additional costs. Off-site laboratory analysis is expensive and time-consuming, often necessitating delay of further activities until results are received. The Three Dimensional Integrated Characterization and Archiving System (3D-ICAS) has been developed to alleviate some of these problems. 3D-ICAS provides a flexible system for physical, chemical and nuclear measurements reduces costs and improves data quality. Operationally, 3D-ICAS performs real-time determinations of hazardous and toxic contamination. A prototype demonstration unit is available for use in early 2000. The tasks in this Phase included: (1) Mobility Platforms: Integrate hardware onto mobility platforms, upgrade surface sensors, develop unit operations and protocol. (2) System Developments: Evaluate metals detection capability using x-ray fluorescence technology. (3) IWOS Upgrades: Upgrade the IWOS software and hardware for compatibility with mobility platform. The system was modified, tested and debugged during 1999 and 2000. The 3D-ICAS was shipped on 11 May 2001 to FIU-HCET for demonstration and validation of the design modifications. These modifications included simplifying the design from a two-vehicle system to a single mobile platform, integration of the XRF sensor for enhanced substrate analysis and upgrading of the IWOS operating system. Several of the system's power supplies were accidentally damaged upon power on because FIU wired 3 phase AC power to the system instead of the requested single phase. Repairs were made in the field to the damaged power supplies but 3 of 5 days time were lost to complete the repairs. Once the repairs were made CyTerra was able to demonstrate the CLR mapping and the movement of the sensor probe to selected locations on the test wall. The XRF sensor was also demonstrated on a stainless steel substrate. A surrogate solution was determined to be below the detection threshold. The radionuclide and GCMS sensors were not demonstrated due to either failed power supply or lack of time remaining in the schedule. The GCMS failure was partially the result of the debugging activities that took place during the week for assessing electrical damage. Specifically, GCMS electronic modules, which control the heating of two of gas transfer elements, may have been damaged during field debugging that was required. Given the financial constraints of the program, CyTerra Corporation decided to return the equipment to Waltham facilities for further assessment. We believe the principles of operation were shown, however a complete demonstration did not occur due to these difficulties.
Three-dimensional NDE of VHTR core components via simulation-based testing
Guzina, Bojan; Kunerth, Dennis
2014-09-30T23:59:59.000Z
A next generation, simulation-driven-and-enabled testing platform is developed for the 3D detection and characterization of defects and damage in nuclear graphite and composite structures in Very High Tempera- ture Reactors (VHTRs). The proposed work addresses the critical need for the development of high-fidelity Non-Destructive Examination (NDE) technologies for as-manufactured and replaceable in-service VHTR com- ponents. Centered around the novel use of elastic (sonic and ultrasonic) waves, this project deploys a robust, non-iterative inverse solution for the 3D defect reconstruction together with a non-contact, laser-based ap- proach to the measurement of experimental waveforms in VHTR core components. In particular, this research (1) deploys three-dimensional Scanning Laser Doppler Vibrometry (3D SLDV) as a means to accurately and remotely measure 3D displacement waveforms over the accessible surface of a VHTR core component excited by mechanical vibratory source; (2) implements a powerful new inverse technique, based on the concept of Topological Sensitivity (TS), for non-iterative elastic waveform tomography of internal defects – that permits robust 3D detection, reconstruction and characterization of discrete damage (e.g. holes and fractures) in nuclear graphite from limited-aperture NDE measurements; (3) implements state-of-the art computational (finite element) model that caters for accurately simulating elastic wave propagation in 3D blocks of nuclear graphite; (4) integrates the SLDV testing methodology with the TS imaging algorithm into a non-contact, high-fidelity NDE platform for the 3D reconstruction and characterization of defects and damage in VHTR core components; and (5) applies the proposed methodology to VHTR core component samples (both two- and three-timensional) with a priori induced, discrete damage in the form of holes and fractures. Overall, the newly established SLDV-TS testing platform represents a next-generation NDE tool that surpasses all exist- ing techniques for the 3D ultrasonic imaging of material damage from non-contact, limited-aperture waveform measurements. Outlook. The next stage in the development of this technology includes items such as (a) non-contact generation of mechanical vibrations in VHTR components via thermal expansion created by high-intensity laser; (b) development and incorporation of Synthetic Aperture Focusing Technique (SAFT) for elevating the accuracy of 3D imaging in highly noisy environments with minimal accessible surface; (c) further analytical and computational developments to facilitate the reconstruction of diffuse damage (e.g. microcracks) in nuclear graphite as they lead to the dispersion of elastic waves, (d) concept of model updating for accurate tracking of the evolution of material damage via periodic inspections; (d) adoption of the Bayesian framework to obtain information on the certainty of obtained images; and (e) optimization of the computational scheme toward real-time, model-based imaging of damage in VHTR core components.
Soft-Lithographical Fabrication of Three-dimensional Photonic Crystals in the Optical Regime
Jae-Hwang Lee
2006-08-09T23:59:59.000Z
This dissertation describes several projects to realize low-cost and high-quality three-dimensional (3D) microfabrication using non-photolithographic techniques for layer-by-layer photonic crystals. Low-cost, efficient 3D microfabrication is a demanding technique not only for 3D photonic crystals but also for all other scientific areas, since it may create new functionalities beyond the limit of planar structures. However, a novel 3D microfabrication technique for photonic crystals implies the development of a complete set of sub-techniques for basic layer-by-layer stacking, inter-layer alignment, and material conversion. One of the conventional soft lithographic techniques, called microtransfer molding ({mu}TM), was developed by the Whitesides group in 1996. Although {mu}TM technique potentially has a number of advantages to overcome the limit of conventional photolithographic techniques in building up 3D microstructures, it has not been studied intensively after its demonstration. This is mainly because of technical challenges in the nature of layer-by-layer fabrication, such as the demand of very high yield in fabrication. After two years of study on conventional {mu}TM, We have developed an advanced microtransfer molding technique, called two-polymer microtransfer molding (2P-{mu}TM) that shows an extremely high yield in layer-by-layer microfabrication sufficient to produce highly layered microstructures. The use of two different photo-curable prepolymers, a filler and an adhesive, allows for fabrication of layered microstructures without thin films between layers. The capabilities of 2P-{mu}TM are demonstrated by the fabrication of a wide-area 12-layer microstructure with high structural fidelity. Second, we also had to develop an alignment technique. We studied the 1st-order diffracted moire fringes of transparent multilayered structures comprised of irregularly deformed periodic patterns. By a comparison study of the diffracted moire fringe pattern and detailed microscopy of the structure, we show that the diffracted moire fringe can be used as a nondestructive tool to analyze the alignment of multilayered structures. We demonstrate the alignment method for the case of layer-by-layer microstructures using soft lithography. The alignment method yields high contrast of fringes even when the materials being aligned have very weak contrasts. The imaging method of diffracted moire fringes is a versatile visual tool for the microfabrication of transparent deformable microstructures in layer-by-layer fashion. Third, we developed several methods to convert a polymer template to dielectric or metallic structures, for instance, metallic infiltration using electrodeposition, metallic coating using sputter deposition, dielectric infiltration using titania nano-slurry, and dielectric coating using atomic layer deposition of Titania. By several different developed techniques, high quality photonic crystals have been successfully fabricated; however, I will focus on a line of techniques to reach metallic photonic crystals in this dissertation since they are completely characterized at this moment. In addition to the attempts for photonic crystal fabrication, our non-photolithographic technique is applied for other photonic applications such as small optical waveguides whose diameter is comparable to the wavelength of guided light. Although, as guiding medium, polymers have tremendous potential because of their enormous variation in optical, chemical and mechanical properties, their application for optical waveguides is limited in conventional photolithography. By 2P-{mu}TM, we achieve low cost, high yield, high fidelity, and tailorable fabrication of small waveguides. Embedded semiconductor quantum-dots and grating couplers are used for efficient internal and external light source, respectively.
Ng, Chung-Sang
-Poisson equations can now be solved by using Fourier transform in space and Laplace transform in time, given an initial value of f(0). 2. The Laplace transform of the electric potential ~(k, p) now satisfies equation using Fourier transform in the Vlasov approach. 3. The solution ~(k, p) is in the form of ~(k, p
Laguerre polynomials and the inverse Laplace transform using discrete data
Lien, Tran Ngoc; Dinh, Alain Pham Ngoc
2007-01-01T23:59:59.000Z
We consider the problem of finding a function defined on $(0,\\infty)$ from a countable set of values of its Laplace transform. The problem is severely ill-posed. We shall use the expansion of the function in a series of Laguerre polynomials to convert the problem in an analytic interpolation problem. Then, using the coefficients of Lagrange polynomials we shall construct a stable approximation solution.
Thermodynamics of the Three-dimensional Black Hole with a Coulomb-like Field
Alexis Larranaga; Luz Angela Garcia
2008-11-21T23:59:59.000Z
In this paper, we study the thermodynamical properties of the (2+1)dimensional black hole with a Coulomb-like electric field and the differential form of the first law of thermodynamics is derived considering a virtual displacement of its event horizon. This approach shows that it is possible to give a thermodynamical interpretation to the field equations near the horizon. The Lambda=0 solution is studied and its interesting thermodynamical properties are commented.
Three-dimensional stationary cyclic symmetric Einstein-Maxwell solutions; black holes
Garcia, Alberto A. [Departamento de Fisica, Centro de Investigacion y de Estudios Avanzados del IPN, Apdo. Postal 14-740, 07000 Mexico, DF (Mexico); Department of Physics, University of California, Davis, CA 95616 (United States)], E-mail: aagarcia@fis.cinvestav.mx
2009-09-15T23:59:59.000Z
From a general metric for stationary cyclic symmetric gravitational fields coupled to Maxwell electromagnetic fields within the (2 + 1)-dimensional gravity the uniqueness of wide families of exact solutions is established. Among them, all uniform electromagnetic solutions possessing electromagnetic fields with vanishing covariant derivatives, all fields having constant electromagnetic invariants F{sub {mu}}{sub {nu}}F{sup {mu}}{sup {nu}} and T{sub {mu}}{sub {nu}}T{sup {mu}}{sup {nu}}, the whole classes of hybrid electromagnetic solutions, and also wide classes of stationary solutions are derived for a third-order nonlinear key equation. Certain of these families can be thought of as black hole solutions. For the most general set of Einstein-Maxwell equations, reducible to three nonlinear equations for the three unknown functions, two new classes of solutions - having anti-de Sitter spinning metric limit - are derived. The relationship of various families with those reported by different authors' solutions has been established. Among the classes of solutions with cosmological constant a relevant place is occupied by the electrostatic and magnetostatic Peldan solutions, the stationary uniform and spinning Clement classes, the constant electromagnetic invariant branches with the particular Kamata-Koikawa solution, the hybrid cyclic symmetric stationary black hole fields, and the non-less important solutions generated via SL(2,R)-transformations where the Clement spinning charged solution, the Martinez-Teitelboim-Zanelli black hole solution, and Dias-Lemos metric merit mention.
Nagakura, Hiroki [Yukawa Institute for Theoretical Physics, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502 (Japan); Sumiyoshi, Kohsuke [Numazu College of Technology, Ooka 3600, Numazu, Shizuoka 410-8501 (Japan); Yamada, Shoichi [Advanced Research Institute for Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555 (Japan)
2014-10-01T23:59:59.000Z
We propose a novel numerical method for solving multi-dimensional, special relativistic Boltzmann equations for neutrinos coupled with hydrodynamics equations. This method is meant to be applied to simulations of core-collapse supernovae. We handle special relativity in a non-conventional way, taking account of all orders of v/c. Consistent treatment of the advection and collision terms in the Boltzmann equations has been a challenge, which we overcome by employing two different energy grids: Lagrangian remapped and laboratory fixed grids. We conduct a series of basic tests and perform a one-dimensional simulation of core-collapse, bounce, and shock-stall for a 15 M {sub ?} progenitor model with a minimum but essential set of microphysics. We demonstrate in the latter simulation that our new code is capable of handling all phases in core-collapse supernova. For comparison, a non-relativistic simulation is also conducted with the same code, and we show that they produce qualitatively wrong results in neutrino transfer. Finally, we discuss a possible incorporation of general relativistic effects into our method.
A four-equation two-phase flow model for sodium boiling simulation of LMFBR fuel assemblies
Schor, Andrei L.
1982-01-01T23:59:59.000Z
A three-dimensional numerical model for the simulation of sodium boiling transients has been developed. The model uses mixture mass and energy equations, while employing a separate momentum equation for each phase. Thermal ...
Ata-ur-Rahman,; Qamar, A. [Institute of Physics and Electronics, University of Peshawar, Peshawar 25000 (Pakistan) [Institute of Physics and Electronics, University of Peshawar, Peshawar 25000 (Pakistan); National Centre for Physics, QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan); Masood, W. [National Centre for Physics, QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan) [National Centre for Physics, QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan); COMSATS, Institute of Information Technology, Park Road, Chak Shahzad, Islamabad 44000 (Pakistan); Eliasson, B. [Physics Department, University of Strathclyde, Glasgow G4 0NG, Scotland (United Kingdom)] [Physics Department, University of Strathclyde, Glasgow G4 0NG, Scotland (United Kingdom)
2013-09-15T23:59:59.000Z
In this paper, small but finite amplitude electrostatic solitary waves in a relativistic degenerate magnetoplasma, consisting of relativistically degenerate electrons and non-degenerate cold ions, are investigated. The Zakharov-Kuznetsov equation is derived employing the reductive perturbation technique and its solitary wave solution is analyzed. It is shown that only compressive electrostatic solitary structures can propagate in such a degenerate plasma system. The effects of plasma number density, ion cyclotron frequency, and direction cosines on the profiles of ion acoustic solitary waves are investigated and discussed at length. The relevance of the present investigation vis-a-vis pulsating white dwarfs is also pointed out.
Exact solutions of three dimensional black holes: Einstein gravity vs F(R) gravity
S. H. Hendi; B. Eslam Panah; R. Saffari
2014-10-28T23:59:59.000Z
In this paper, we consider Einstein gravity in the presence of a class of nonlinear electrodynamics, called power Maxwell invariant (PMI). We take into account $(2+1)$-dimensional spacetime in Einstein-PMI gravity and obtain its black hole solutions. Then, we regard pure $F(R)$ gravity as well as $F(R)$-conformally invariant Maxwell theory to obtain exact solutions of the field equations with black hole interpretation. Finally, we investigate the conserved and thermodynamic quantities and discuss about the first law of thermodynamics for the mentioned gravitational models.
Yupari, Ricardo
1985-01-01T23:59:59.000Z
using the computer code BOLD VENTURE. BOLD VENTURE is a modular type computational system which was developed by Oak Ridge National Laborator y for nuclear r eactor analysis. VENTURE is the neutronics module which implements a f inite...-dif'ference solution of the multigroup diffusion equations in 3-D geometry. The computer code was loaded and compiled on the TAMU AMDAHL computer, and sample pr oblems were run in or der to test the performance of each of the computational modules. The effective...
Schilling, O; Latini, M
2010-01-12T23:59:59.000Z
The dynamics of the reshocked multi-mode Richtmyer-Meshkov instability is investigated using 513 x 257{sup 2} three-dimensional ninth-order weighted essentially nonoscillatory shock-capturing simulations. A two-mode initial perturbation with superposed random noise is used to model the Mach 1.5 air/SF{sub 6} Vetter-Sturtevant shock tube experiment. The mass fraction and enstrophy isosurfaces, and density cross-sections are utilized to show the detailed flow structure before, during, and after reshock. It is shown that the mixing layer growth agrees well with the experimentally measured growth rate before and after reshock. The post-reshock growth rate is also in good agreement with the prediction of the Mikaelian model. A parametric study of the sensitivity of the layer growth to the choice of amplitudes of the short and long wavelength initial interfacial perturbation is also presented. Finally, the amplification effects of reshock are quantified using the evolution of the turbulent kinetic energy and turbulent enstrophy spectra, as well as the evolution of the baroclinic enstrophy production, buoyancy production, and shear production terms in the enstrophy and turbulent kinetic transport equations.
McCann, R.A.
1980-12-01T23:59:59.000Z
A finite difference computer code, named HYDRA-I, has been developed to simulate the three-dimensional performance of a spent fuel assembly contained within a cylindrical canister. The code accounts for the coupled heat transfer modes of conduction, convection, and radiation and permits spatially varying boundary conditions, thermophysical properties, and power generation rates. This document is intended as a manual for potential users of HYDRA-I. A brief discussion of the governing equations, the solution technique, and a detailed description of how to set up and execute a problem are presented. HYDRA-I is designed for operation on a CDC 7600 computer. An appendix is included that summarizes approximately two dozen different cases that have been examined. The cases encompass variations in fuel assembly and canister configurations, power generation rates, filler materials, and gases. The results presented show maximum and various local temperatures and heat fluxes illustrating the changing importance of the three heat transfer modes. Finally, the need for comparison with experimental data is emphasized as an aid in code verification although the limited data available indicate excellent agreement.
Three-Dimensional Simulation of Forebay and Turbine Intakes Flows for the Bonneville Project
Rakowski, Cynthia L.; Richmond, Marshall C.; Serkowski, John A.; Ebner, Laurie L.
2002-12-31T23:59:59.000Z
Natural resource applications of computational fluid dynamics (CFD) models are becoming more frequent with the advances in computational power and the availability of commercial meshing software and verified CFD solver applications. The Bonneville Lock and Dam Project, constructed and operated by the U. S. Army Corps of Engineers, is the westernmost dam on the Columbia River, and is located about 40 miles upstream of Portland, Oregon. A set of 3D CFD models have been developed for the Bonneville Project forebay and turbine intakes; the CFD models provide a tool to predict the impact of proposed changes in operational rules both for the overall river flow patterns and near the turbine intakes. These models also offer rapid insight into the performance of proposed or existing hydraulic structures. The creation of a computational domain for Bonneville was complex and required the use of many software tools to integrate the diverse data sources that described the river and powerhouse geometry into a single computational domain. Once the computational mesh was created, flows were simulated by solving the Reynolds-averaged Navier-Stokes (RANS) equations together with a two-equation (k-epsilon) turbulence model. The model was validated using velocity data measured in reduced scale physical models and in the field.
Shi-Lei Su; Xiao-Qiang Shao; Hong-Fu Wang; Shou Zhang
2014-08-21T23:59:59.000Z
We propose a dissipative scheme to prepare a three-dimensional entangled state for two atoms trapped in separate coupled cavities. Our work shows that both atomic spontaneous emission and cavity decay, which are two typical obstacles in unitary-dynamics-based schemes, could be utilized as resources for high-dimensional entangled state preparation without specifying initial state and controlling time precisely. Final numerical simulation with one group of experimental parameters indicates that the performance of our scheme is better than the unitary-dynamics-based scheme.
Faber, Derrek M.; Weiland, Mark A.; Moursund, Robert; Carlson, Thomas J.; Adams, Noah; Rhondorf, D.
2001-05-01T23:59:59.000Z
This report describes tests conducted at Bonneville Dam on the Columbia River in the spring of 2000 using three-dimensional acoustic telemetry and computational fluid dynamics hydraulic modeling to observe the response of outmigrating juvenile steelhead and yearling chinook to a prototype surface collector installed at the Powerhouse. The study described in this report was one of several conducted for the U.S. Army Corps of Engineers to prepare a decision document on which of two bypass methods: surface flow bypass or extended-length submersible bar screens to use to help smolts pass around Bonneville dams without going through the turbines.
Coexistence of Two- and Three-dimensional Shubnikov-de Haas Oscillations in Ar^+ -irradiated KTaO_3
Harashima, S.; Bell, C.; Kim, M.; Yajima, T.; Hikita, Y.; Hwang, H.Y.
2012-05-16T23:59:59.000Z
We report the electron doping in the surface vicinity of KTaO{sub 3} by inducing oxygen-vacancies via Ar{sup +}-irradiation. The doped electrons have high mobility (> 10{sup 4} cm{sup 2}/Vs) at low temperatures, and exhibit Shubnikov-de Haas oscillations with both two- and three-dimensional components. A disparity of the extracted in-plane effective mass, compared to the bulk values, suggests mixing of the orbital characters. Our observations demonstrate that Ar{sup +}-irradiation serves as a flexible tool to study low dimensional quantum transport in 5d semiconducting oxides.
Nelson, George J.; Harris, William M.; Izzo, John R. Jr.; Grew, Kyle N.; Chiu, Wilson K. S. [HeteroFoaM Center, a DOE Energy Frontier Research Center, Department of Mechanical Engineering, University of Connecticut, 191 Auditorium Rd., Storrs, Connecticut 06269-3139 (United States); Chu, Yong S. [National Synchrotron Light Source II, Brookhaven National Laboratory, Bldg. 703 Upton, New York 11973-5000 (United States); Yi, Jaemock [Advanced Photon Source, Argonne National Laboratory, 9700 S. Cass Ave., Bldg. 438-B007 Argonne, Illinois 60439 (United States); Andrews, Joy C.; Liu Yijin; Pianetta, Piero [Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Rd., MS 69 Menlo Park, California 94025 (United States)
2011-04-25T23:59:59.000Z
The reduction-oxidation cycling of the nickel-based oxides in composite solid oxide fuel cells and battery electrodes is directly related to cell performance. A greater understanding of nickel redox mechanisms at the microstructural level can be achieved in part using transmission x-ray microscopy (TXM) to explore material oxidation states. X-ray nanotomography combined with x-ray absorption near edge structure (XANES) spectroscopy has been applied to study samples containing distinct regions of nickel and nickel oxide (NiO) compositions. Digitally processed images obtained using TXM demonstrate the three-dimensional chemical mapping and microstructural distribution capabilities of full-field XANES nanotomography.
P. Chung; P. Danielewicz
2008-07-30T23:59:59.000Z
A model-independent, three-dimensional source function for pion pairs has been extracted from Pb+Pb collisions at $\\sqrt s_{NN}=17.3$ AGeV. The extracted sourc e exhibits long-range non-Gaussian tails in the directions of the pion-pair net transverse-momentum and of the beam. Comparison with the Therminator model allow s for an extraction of the pion source proper breakup time and of emission durat ion in the collisions.
Prerna Sharma; P. Aswathi; Anit Sane; Shankar Ghosh; S. Bhattacharya
2011-03-22T23:59:59.000Z
Two-fluid interfaces in porous media, an example of driven disordered systems, were studied by a real time three-dimensional imaging technique with pore scale resolution for a less viscous fluid displacing a more viscous one. With increasing flow rate the interface transforms from flat to fingers and thence to droplets for both drainage and imbibition. The results compare and contrast the effects of randomness, both physical (geometry of the pore space) and chemical (wettability of the fluids), on the dynamical instability and identify the origin of the pore-scale processes that govern them.
Three-dimensional isotropic perfect lens based on LC-loaded transmission lines
P. Alitalo; S. Maslovski; S. Tretyakov
2005-09-16T23:59:59.000Z
An isotropic three-dimentional perfect lens based on cubic meshes of interconnected transmission lines and bulk loads is proposed. The lens is formed by a slab of a loaded mesh placed in between two similar unloaded meshes. The dispersion equations and the characteristic impedances of the eigenwaves in the meshes are derived analytically, with an emphasis on generality. This allows designing of transmission-line meshes with desired dispersion properties. The required backward-wave mode of operation in the lens is realized with simple inductive and capacitive loads. An analytical expression for the transmission through the lens is derived and the amplification of evanescent waves is demonstrated. Factors that influence enhancement of evanescent waves in the lens are studied and the corresponding design criteria are established. A possible realization of the structure is outlined.
Two- and three-dimensional simulations of core-collapse supernovae with CHIMERA
Lentz, Eric J; Harris, J Austin; Chertkow, Merek Austin; Hix, W Raphael; Mezzacappa, Anthony; Messer, O E Bronson; Bondin, John M; Marronetti, Pedro; Mauney, Christopher M; Yakunin, Konstantin N
2013-01-01T23:59:59.000Z
Ascertaining the core-collapse supernova mechanism is a complex, and yet unsolved, problem dependent on the interaction of general relativity, hydrodynamics, neutrino transport, neutrino-matter interactions, and nuclear equations of state and reaction kinetics. Ab initio modeling of core-collapse supernovae and their nucleosynthetic outcomes requires care in the coupling and approximations of the physical components. We have built our multi-physics CHIMERA code for supernova modeling in 1-, 2-, and 3-D, using ray-by-ray neutrino transport, approximate general relativity, and detailed neutrino and nuclear physics. We discuss some early results from our current series of exploding 2D simulations and our work to perform computationally tractable simulations in 3D using the "Yin-Yang" grid.
Two- and three-dimensional simulations of core-collapse supernovae with CHIMERA
Lentz, Eric J [ORNL] [ORNL; Bruenn, S. W. [Florida Atlantic University, Boca Raton] [Florida Atlantic University, Boca Raton; Harris, James A [ORNL] [ORNL; Chertkow, Merek A [ORNL] [ORNL; Hix, William Raphael [ORNL] [ORNL; Mezzacappa, Anthony [ORNL] [ORNL; Messer, Bronson [ORNL] [ORNL; Blondin, J. M. [North Carolina State University] [North Carolina State University; Marronetti, Pedro [Florida Atlantic University, Boca Raton] [Florida Atlantic University, Boca Raton; Mauney, Christopher M [ORNL] [ORNL; Yakunin, Konstantin [Florida Atlantic University, Boca Raton] [Florida Atlantic University, Boca Raton
2012-01-01T23:59:59.000Z
Ascertaining the core-collapse supernova mechanism is a complex, and yet unsolved, problem dependent on the interaction of general relativity, hydrodynamics, neutrino transport, neutrino-matter interactions, and nuclear equations of state and reaction kinetics. Ab initio modeling of core-collapse supernovae and their nucleosynthetic outcomes requires care in the coupling and approximations of the physical components. We have built our multi-physics CHIMERA code for supernova modeling in 1-, 2-, and 3-D, using ray-by-ray neutrino transport, approximate general relativity, and detailed neutrino and nuclear physics. We discuss some early results from our current series of exploding 2D simulations and our work to perform computationally tractable simulations in 3D using the ``Yin--Yang'' grid.
Buckholtz, H.T.; Biermann, A.H.
1980-01-01T23:59:59.000Z
A computational model to simulate the dispersion and coagulation of aerosols emitted from coal-fired power plants was constructed. In modeling the dispersion of the aerosol, turbulent diffusion and wind-driven advection are treated by a finite-difference method. Molecular coagulation is incorporated in the model to follow shifts in the particle-size distribution. Particulate coagulation is mathematically described by Timiskii's equation. The relevent semi-empirical work of Smirnov is incorporated in the model to provide for the coagultion constant. Input for the model is a bimodal, particle-size distribution measured at an operating coal-fired power plant. Simulations indicate that dispersion competes against coagulation mechanisms to maintain the bimodal shaped distribution for 32 km. Turbulence and particle settling tend to enchance coagulation effects. The size-dependent spatial segregation of particles within the plume is predicted.
Applications of Laplace transformations to evaluation of definite integrals
Yonkers, John Dale
1964-01-01T23:59:59.000Z
. Evaluate the integral n p sin t cos t dt. 0 t n In order to find the Laplace transform of sin t cos t, we can use n DeMoivre's theorem to express sin t cos t as a linear combination of sines and cosines. This theorem states that n (cos x + i sin x... I ? INTRODUCTION CHAPTER II ? INTEGRALS CONTAINING A PARAMETER- ? ? - - Z CHAPTER III INTEGRALS CONTAINING INVERSE TRANS F ORMS CHAPTER IV ? INTEGRALS OF THE FORM J ~Ft dt ? ? ? ? - -14 0 t CHAPTER V ? INTEGRALS OF THE FORM J t F(t) dt...
Thorne, P.D.; Chamness, M.A.
1992-11-01T23:59:59.000Z
This report presents the status of development of a three-dimensional conceptual model for the unconfined aquifer system at Hanford. A conceptual model is needed to support development of a realistic three-dimensional numerical model for predicting ground-water flow and the transport of contaminants. The report focuses on developing a hydrogeologic framework, assessing available hydraulic property data, describing flow-system boundaries, and evaluating areal recharge and leakage. Geologic descriptions of samples obtained during well drilling were used to prepare cross sections that correlate relatively continuous layers. The layers were defined based on textural differences that are expected to reflect differences in hydraulic properties. Assigning hydraulic properties to the layers is a critical part of the conceptual model. Available hydraulic property data for the study area were compiled and were correlated with the geologic layers where possible. Flow-system boundaries are present within the study area at basalt outcrops and at the Columbia River. Boundary conditions have been evaluated for these areas. Available estimates of areal recharge from precipitation were compiled.
Adamovich, Igor V. [Nonequilibrium Thermodynamics Laboratory, Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio 43210 (United States)] [Nonequilibrium Thermodynamics Laboratory, Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio 43210 (United States)
2014-04-15T23:59:59.000Z
A three-dimensional, nonperturbative, semiclassical analytic model of vibrational energy transfer in collisions between a rotating diatomic molecule and an atom, and between two rotating diatomic molecules (Forced Harmonic Oscillator–Free Rotation model) has been extended to incorporate rotational relaxation and coupling between vibrational, translational, and rotational energy transfer. The model is based on analysis of semiclassical trajectories of rotating molecules interacting by a repulsive exponential atom-to-atom potential. The model predictions are compared with the results of three-dimensional close-coupled semiclassical trajectory calculations using the same potential energy surface. The comparison demonstrates good agreement between analytic and numerical probabilities of rotational and vibrational energy transfer processes, over a wide range of total collision energies, rotational energies, and impact parameter. The model predicts probabilities of single-quantum and multi-quantum vibrational-rotational transitions and is applicable up to very high collision energies and quantum numbers. Closed-form analytic expressions for these transition probabilities lend themselves to straightforward incorporation into DSMC nonequilibrium flow codes.
Bradley, M.M.; Peterson, K.R.; Rodriguez, D.J.
1988-11-17T23:59:59.000Z
During the hours immediately following a nuclear exchange, large fires could inject enormous quantities of smoke into the atmosphere. This smoke, together with dust from surface bursts, would severely restrict visibilities and darken the skies over large areas for days. This, in turn, could impact surface and air operations and systems. These effects could be mitigated by various scavenging mechanisms within the convective clouds that form above the fires. In order to evaluate impacts of post-nuclear-exchange smoke injection, we are developing a three-dimensional numerical smoke plume model (OCTET) to simulate the dynamics and microphysical processes within smoke plumes and convective clouds above large fires. This model is based on the dynamic framework of the Klemp-Wilhelmson (1978) convective storm model and includes parameterizations of scavenging processes. In addition, we are combining results of laboratory research, field experiments, and detailed numerical modeling of cloud microphysical processes in order to better understand smoke scavenging mechanisms. In this brief demonstration of capabilities, we present results from the OCTET model and from a three-dimensional mesoscale model. The smoke plume and fire-induced cloud simulations demonstrate the effects of nucleation scavenging, seasonal variation of atmospheric stability, and various fuel sources. The mesoscale simulations (that use the plume model output as input) demonstrate the mesoscale transport and diffusion of smoke and predict optical depths over the hypothetical target area. No dust effects have been included in these simulations. 2 refs., 8 figs.
Li, Danda
2011-08-31T23:59:59.000Z
Breast cancer has a high prevalence among women and most patients suffer from metastasis to bone. The mechanisms involved in breast cancer bone metastasis are poorly understood. Three-dimensional (3D) tissue culture systems are becoming a focus...
Dutkiewicz, Stephanie.
We describe the coupling of a three-dimensional ocean circulation model, with explicit thermodynamic seaice and ocean carbon cycle representations, to a two-dimensional atmospheric/land model. This coupled system has been ...
Kim, Kyoohyun
We present high-resolution optical tomographic images of human red blood cells (RBC) parasitized by malaria-inducing Plasmodium falciparum (Pf)-RBCs. Three-dimensional (3-D) refractive index (RI) tomograms are reconstructed ...
Welch, Stephen; Miles, Steward; Kumar, Suresh; Lemaire, Tony; Chan, Alan
A hierarchy of coupling strategies for integrating advanced three-dimensional modelling methodologies for prediction of the thermo-mechanical response of structures in fire has been developed and systematically assessed. ...
Color Images for LBL 38618 June 10, 1996 4 Figure 7. Three dimensional view of reservoir to UTCHEM. In a simulation of a waterflood, a finger of unswept oil is detected (3a) then removed
Three-dimensional linear peeling-ballooning theory in magnetic fusion devices
Weyens, T., E-mail: tweyens@fis.uc3m.es; Sánchez, R.; García, L. [Departamento de Física, Universidad Carlos III de Madrid, Madrid 28911 (Spain)] [Departamento de Física, Universidad Carlos III de Madrid, Madrid 28911 (Spain); Loarte, A.; Huijsmans, G. [ITER Organization, Route de Vinon sur Verdon, 13067 Saint Paul Lez Durance (France)] [ITER Organization, Route de Vinon sur Verdon, 13067 Saint Paul Lez Durance (France)
2014-04-15T23:59:59.000Z
Ideal magnetohydrodynamics theory is extended to fully 3D magnetic configurations to investigate the linear stability of intermediate to high n peeling-ballooning modes, with n the toroidal mode number. These are thought to be important for the behavior of edge localized modes and for the limit of the size of the pedestal that governs the high confinement H-mode. The end point of the derivation is a set of coupled second order ordinary differential equations with appropriate boundary conditions that minimize the perturbed energy and that can be solved to find the growth rate of the perturbations. This theory allows of the evaluation of 3D effects on edge plasma stability in tokamaks such as those associated with the toroidal ripple due to the finite number of toroidal field coils, the application of external 3D fields for elm control, local modification of the magnetic field in the vicinity of ferromagnetic components such as the test blanket modules in ITER, etc.
Electromagnetic energy conversion in downstream fronts from three dimensional kinetic reconnection
Lapenta, Giovanni [Departement Wiskunde, KU Leuven, Universiteit Leuven (Belgium)] [Departement Wiskunde, KU Leuven, Universiteit Leuven (Belgium); Goldman, Martin; Newman, David [University of Colorado, Colorado 80309 (United States)] [University of Colorado, Colorado 80309 (United States); Markidis, Stefano [High Performance Computing and Visualization (HPCViz) Department, KTH Royal Institute of Technology, Stockholm (Sweden)] [High Performance Computing and Visualization (HPCViz) Department, KTH Royal Institute of Technology, Stockholm (Sweden); Divin, Andrey [Swedish Institute of Space Physics, Uppsala (Sweden)] [Swedish Institute of Space Physics, Uppsala (Sweden)
2014-05-15T23:59:59.000Z
The electromagnetic energy equation is analyzed term by term in a 3D simulation of kinetic reconnection previously reported by Vapirev et al. [J. Geophys. Res.: Space Phys. 118, 1435 (2013)]. The evolution presents the usual 2D-like topological structures caused by an initial perturbation independent of the third dimension. However, downstream of the reconnection site, where the jetting plasma encounters the yet unperturbed pre-existing plasma, a downstream front is formed and made unstable by the strong density gradient and the unfavorable local acceleration field. The energy exchange between plasma and fields is most intense at the instability, reaching several pW/m{sup 3}, alternating between load (energy going from fields to particles) and generator (energy going from particles to fields) regions. Energy exchange is instead purely that of a load at the reconnection site itself in a region focused around the x-line and elongated along the separatrix surfaces. Poynting fluxes are generated at all energy exchange regions and travel away from the reconnection site transporting an energy signal of the order of about S?10{sup ?3}W/m{sup 2}.
Three-dimensional electromagnetic modeling and inversion on massively parallel computers
Newman, G.A.; Alumbaugh, D.L. [Sandia National Labs., Albuquerque, NM (United States). Geophysics Dept.
1996-03-01T23:59:59.000Z
This report has demonstrated techniques that can be used to construct solutions to the 3-D electromagnetic inverse problem using full wave equation modeling. To this point great progress has been made in developing an inverse solution using the method of conjugate gradients which employs a 3-D finite difference solver to construct model sensitivities and predicted data. The forward modeling code has been developed to incorporate absorbing boundary conditions for high frequency solutions (radar), as well as complex electrical properties, including electrical conductivity, dielectric permittivity and magnetic permeability. In addition both forward and inverse codes have been ported to a massively parallel computer architecture which allows for more realistic solutions that can be achieved with serial machines. While the inversion code has been demonstrated on field data collected at the Richmond field site, techniques for appraising the quality of the reconstructions still need to be developed. Here it is suggested that rather than employing direct matrix inversion to construct the model covariance matrix which would be impossible because of the size of the problem, one can linearize about the 3-D model achieved in the inverse and use Monte-Carlo simulations to construct it. Using these appraisal and construction tools, it is now necessary to demonstrate 3-D inversion for a variety of EM data sets that span the frequency range from induction sounding to radar: below 100 kHz to 100 MHz. Appraised 3-D images of the earth`s electrical properties can provide researchers opportunities to infer the flow paths, flow rates and perhaps the chemistry of fluids in geologic mediums. It also offers a means to study the frequency dependence behavior of the properties in situ. This is of significant relevance to the Department of Energy, paramount to characterizing and monitoring of environmental waste sites and oil and gas exploration.
Building accurate initial models using gain functions for waveform inversion in the Laplace domain
Wansoo Ha; Changsoo Shin
2014-08-20T23:59:59.000Z
We suggest an initial model building technique using time gain functions in the Laplace domain. Applying the gain expressed as a power of time is equivalent to taking the partial derivative of the Laplace-domain wavefield with respect to a damping constant. We construct an objective function, which minimizes the logarithmic differences between the gained field data and the partial derivative of the modeled data with respect to the damping constant. We calculate the modeled wavefield, the partial derivative wavefield, and the gradient direction in the Laplace domain using the analytic Green's function starting from a constant velocity model. This is an efficient method to generate an accurate initial model for a following Laplace-domain inversion. Numerical examples using two marine field datasets confirm that a starting model updated once from a scratch using the gradient direction calculated with the proposed method can be successfully used for a subsequent Laplace-domain inversion.
Attota, Ravikiran, E-mail: Ravikiran.attota@nist.gov; Dixson, Ronald G. [Semiconductor and Dimensional Metrology Division, NIST, Gaithersburg, Maryland 20899 (United States)
2014-07-28T23:59:59.000Z
We experimentally demonstrate that the three-dimensional (3-D) shape variations of nanometer-scale objects can be resolved and measured with sub-nanometer scale sensitivity using conventional optical microscopes by analyzing 4-D optical data using the through-focus scanning optical microscopy (TSOM) method. These initial results show that TSOM-determined cross-sectional (3-D) shape differences of 30?nm–40?nm wide lines agree well with critical-dimension atomic force microscope measurements. The TSOM method showed a linewidth uncertainty of 1.22?nm (k?=?2). Complex optical simulations are not needed for analysis using the TSOM method, making the process simple, economical, fast, and ideally suited for high volume nanomanufacturing process monitoring.
Zhu Feipeng; Shi Hongjian; Bai Pengxiang; He Xiaoyuan
2011-04-10T23:59:59.000Z
In fringe projection, the CCD camera and the projector are often placed at equal height. In this paper, we will study the calibration of an unequal arrangement of the CCD camera and the projector. The principle of fringe projection with two-dimensional digital image correlation to acquire the profile of object surface is described in detail. By formula derivation and experiment, the linear relationship between the out-of-plane calibration coefficient and the y coordinate is clearly found. To acquire the three-dimensional (3D) information of an object correctly, this paper presents an effective calibration method with linear least-squares fitting, which is very simple in principle and calibration. Experiments are implemented to validate the availability and reliability of the calibration method.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
King, Travis L.; Gatimu, Enid N.; Bohn, Paul W.
2009-01-01T23:59:59.000Z
This paper presents a study of electrokinetic transport in single nanopores integrated into vertically-stacked three-dimensional hybrid microfluidic/nanofluidic structures. In these devices single nanopores, created by focused ion beam (FIB) milling in thin polymer films, provide fluidic connection between two vertically separated, perpendicular microfluidic channels. Experiments address both systems in which the nanoporous membrane is composed of the same (homojunction) or different (heterojunction) polymer as the microfluidic channels. These devices are then used to study the electrokinetic transport properties of synthetic (i.e., polystyrene sulfonate and polyallylamine) and biological (i.e.,DNA) polyelectrolytes across these nanopores. Single nanopore transport of polyelectrolytes across these nanoporesmore »using both electrical current measurements and confocal microscopy. Both optical and electrical measurements indicate that electroosmotic transport is predominant over electrophoresis in single nanopores with d > 180 nm, consistent with results obtained under similar conditions for nanocapillary array membranes.« less
Nelson, Celeste M.; Inman, Jamie L.; Bissell, Mina J.
2008-02-13T23:59:59.000Z
Here we describe a simple micromolding method to construct three-dimensional arrays of organotypic epithelial tissue structures that approximate in vivo histology. An elastomeric stamp containing an array of posts of defined geometry and spacing is used to mold microscale cavities into the surface of type I collagen gels. Epithelial cells are seeded into the cavities and covered with a second layer of collagen. The cells reorganize into hollow tissues corresponding to the geometry of the cavities. Patterned tissue arrays can be produced in 3-4 h and will undergo morphogenesis over the following one to three days. The protocol can easily be adapted to study a variety of tissues and aspects of normal and neoplastic development.
João H. Bettencourt; Cristóbal López; Emilio Hernández-García
2012-07-09T23:59:59.000Z
We study three dimensional oceanic Lagrangian Coherent Structures (LCSs) in the Benguela region, as obtained from an output of the ROMS model. To do that we first compute Finite-Size Lyapunov exponent (FSLE) fields in the region volume, characterizing mesoscale stirring and mixing. Average FSLE values show a general decreasing trend with depth, but there is a local maximum at about 100 m depth. LCSs are extracted as ridges of the calculated FSLE fields. They present a "curtain-like" geometry in which the strongest attracting and repelling structures appear as quasivertical surfaces. LCSs around a particular cyclonic eddy, pinched off from the upwelling front are also calculated. The LCSs are confirmed to provide pathways and barriers to transport in and out of the eddy.
Ramis, R., E-mail: rafael.ramis@upm.es [E.T.S.I. Aeronáuticos, Universidad Politécnica de Madrid, P. Cardenal Cisneros 3, E-28040 Madrid (Spain); Temporal, M. [Centre de Mathématiques et de Leurs Applications, ENS Cachan and CNRS, 61 Av. du President Wilson, F-94235 Cachan Cedex (France); Canaud, B.; Brandon, V. [CEA, DIF, F-91297 Arpajon (France)
2014-08-15T23:59:59.000Z
The symmetry of a Direct-Drive (DD) irradiation scheme has been analyzed by means of three-dimensional (3D) simulations carried out by the code MULTI (R. Ramis et al., Comput. Phys. Commun. 49, 475 (1988)) that includes hydrodynamics, heat transport, and 3D laser ray-tracing. The implosion phase of a target irradiated by the Laser Megajoule (LMJ) facility in the context of the Shock Ignition scheme has been considered. The LMJ facility has been designed for Indirect-Drive, and by this reason that the irradiation scheme must be modified when used for DD. Thus, to improve the implosion uniformity to acceptable levels, the beam centerlines should be realigned and the beam power balance should be adjusted. Several alternatives with different levels of complexity are presented and discussed.
Deru, M.; Judkoff, R.; Neymark, J.
2002-08-01T23:59:59.000Z
A three-dimensional, finite-element, heat-transfer computer program was developed to study ground-coupled heat transfer from buildings. It was used in conjunction with the SUNREL whole-building energy simulation program to analyze ground-coupled heat transfer from buildings, and the results were compared with the simple ground-coupled heat transfer models used in whole-building energy simulation programs. The detailed model provides another method of testing and refining the simple models and analyzing complex problems. This work is part of an effort to improve the analysis of the ground-coupled heat transfer in building energy simulation programs. The output from this detailed model and several others will form a set of reference results for use with the BESTEST diagnostic procedure. We anticipate that the results from the work will be incorporated into ANSI/ASHRAE 140-2001, Standard Method of Test for the Evaluation of Building Energy Analysis Computer Programs.
Gudiksen, P.H.; Walton, J.J.; Alpert, D.J.; Johnson, J.D.
1982-01-01T23:59:59.000Z
This work explores the use of principal components analysis coupled to three-dimensional atmospheric transport and dispersion models for evaluating the environmental consequences of reactor accidents. This permits the inclusion of meteorological data from multiple sites and the effects of topography in the consequence evaluation; features not normally included in such analyses. The technique identifies prevailing regional wind patterns and their frequencies for use in the transport and dispersion calculations. Analysis of a hypothetical accident scenario involving a release of radioactivity from a reactor situated in a river valley indicated the technique is quite useful whenever recurring wind patterns exist, as is often the case in complex terrain situations. Considerable differences were revealed in a comparison with results obtained from a more conventional Gaussian plume model using only the reactor site meteorology and no topographic effects.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
King, Travis L. [Univ. of Illinois at Urbana-Champaign, IL (United States). Dept. of Chemistry; Univ. of Notre Dame, South Bend, IN (United States). Dept. of Chemical and Biomolecular Engineering; Gatimu, Enid N. [Univ. of Notre Dame, South Bend, IN (United States). Dept. of Chemical and Biomolecular Engineering; Bohn, Paul W. [Univ. of Notre Dame, South Bend, IN (United States). Dept. of Chemical and Biomolecular Engineering, Dept. of Chemistry and Biochemistry
2009-01-01T23:59:59.000Z
This paper presents a study of electrokinetic transport in single nanopores integrated into vertically-stacked three-dimensional hybrid microfluidic/nanofluidic structures. In these devices single nanopores, created by focused ion beam (FIB) milling in thin polymer films, provide fluidic connection between two vertically separated, perpendicular microfluidic channels. Experiments address both systems in which the nanoporous membrane is composed of the same (homojunction) or different (heterojunction) polymer as the microfluidic channels. These devices are then used to study the electrokinetic transport properties of synthetic (i.e., polystyrene sulfonate and polyallylamine) and biological (i.e.,DNA) polyelectrolytes across these nanopores. Single nanopore transport of polyelectrolytes across these nanopores using both electrical current measurements and confocal microscopy. Both optical and electrical measurements indicate that electroosmotic transport is predominant over electrophoresis in single nanopores with d > 180 nm, consistent with results obtained under similar conditions for nanocapillary array membranes.
Binkowski, F.S. [NOAA, Research Triangle Park, NC (United States); Shankar, U. [MCNC, Research Triangle Park, NC (United States)
1994-12-31T23:59:59.000Z
The Regional Particulate Model, a three-dimensional Eulerian air quality model, was developed to investigate aerosol particle issues of important to the US EPA and to meet the demands of the Clean Air Act amendments of 1990. In addition to aerosol dynamics such as growth and coagulation, the model includes photochemistry, transport, and deposition. A new formulation of dry deposition as a function of the aerosol size distribution has been incorporated into the model. This formulation allows for the representation of dry deposition of total particle number and total particle mass by deposition velocities specifically formulated for these two quantities as a function of particle size. Results for the dry deposition of sulfate mass from the new model will be compared with those from the Tagged Species Engineering Model for a variety of local conditions. The behavior of the aerosol size distribution responding to the new formulation will also be discussed.
Skinner, B.; Chen, T.; Shklovskii, B. I., E-mail: shklovsk@physics.spa.umn.edu [University of Minnesota, Fine Theoretical Physics Institute (United States)
2013-09-15T23:59:59.000Z
In the three-dimensional topological insulator (TI), the physics of doped semiconductors exists literally side-by-side with the physics of ultrarelativistic Dirac fermions. This unusual pairing creates a novel playground for studying the interplay between disorder and electronic transport. In this mini-review, we focus on the disorder caused by the three-dimensionally distributed charged impurities that are ubiquitous in TIs, and we outline the effects it has on both the bulk and surface transport in TIs. We present self-consistent theories for Coulomb screening both in the bulk and at the surface, discuss the magnitude of the disorder potential in each case, and present results for the conductivity. In the bulk, where the band gap leads to thermally activated transport, we show how disorder leads to a smaller-than-expected activation energy that gives way to variable-range hopping at low temperatures. We confirm this enhanced conductivity with numerical simulations that also allow us to explore different degrees of impurity compensation. For the surface, where the TI has gapless Dirac modes, we present a theory of disorder and screening of deep impurities, and we calculate the corresponding zero-temperature conductivity. We also comment on the growth of the disorder potential in passing from the surface of the TI into the bulk. Finally, we discuss how the presence of a gap at the Dirac point, introduced by some source of time-reversal symmetry breaking, affects the disorder potential at the surface and the mid-gap density of states.
Yoshida, Norio, E-mail: noriwo@chem.kyushu-univ.jp [Department of Chemistry, Graduate School of Sciences, Kyushu University, 6-10-1, Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)
2014-06-07T23:59:59.000Z
The three-dimensional reference interaction site model (3D-RISM) method was efficiently implemented in the fragment molecular orbital (FMO) method. The method is referred to as the FMO/3D-RISM method, and allows us to treat electronic structure of the whole of a macromolecule, such as a protein, as well as the solvent distribution around a solute macromolecule. The formalism of the FMO/3D-RISM method, for the computationally available form and variational expressions, are proposed in detail. A major concern leading to the implementation of the method was decreasing the computational costs involved in calculating the electrostatic potential, because the electrostatic potential is calculated on numerous grid points in three-dimensional real space in the 3D-RISM method. In this article, we propose a procedure for decreasing the computational costs involved in calculating the electrostatic potential in the FMO method framework. The strategy involved in this procedure is to evaluate the electrostatic potential and the solvated Fock matrix in different manners, depending on the distance between the solute and the solvent. The electrostatic potential is evaluated directly in the vicinity of the solute molecule by integrating the molecular orbitals of monomer fragments of the solute molecule, whereas the electrostatic potential is described as the sum of multipole interactions when an analog of the fast multipole method is used. The efficiency of our method was demonstrated by applying it to a water trimer system and three biomolecular systems. The FMO/3D-RISM calculation can be performed within a reasonable computational time, retaining the accuracy of some physical properties.
Suzuki, Shigeru, E-mail: shig.suz@gmail.com [Saitama Red Cross Hospital, Department of Radiology (Japan); Yamaguchi, Ichiro [National Institute of Public Health, Department of Environmental Health (Japan); Kidouchi, Takashi; Yamamoto, Asako [Teikyo University School of Medicine, Department of Radiology (Japan); Masumoto, Tomohiko [Tsukuba University Hospital, Department of Radiology (Japan); Ozaki, Yutaka [Juntendo University Nerima Hospital, Department of Radiology (Japan)
2011-04-15T23:59:59.000Z
The purpose of this study was to evaluate the effective dose during abdominal three-dimensional (3D) imaging on phantoms and estimate the dose-area product (DAP) for effective dose conversion factors for three types of angiographic units. Three-dimensional imaging was performed for three sizes (small, medium, large) of human-shaped phantoms using three types of angiographic units (Allura Xper FD20/10, INNOVA 4100, AXIOM Artis dTA). We calculated 25 organ doses and effective doses using Monte Carlo technique for the three phantoms with a program for a personal computer. As benchmark studies to back up the results by Monte Carlo technique, we measured the organ doses directly on the small phantom using radiophotoluminescent glass dosimeters. The DAP value increased as the phantom size increased. The organ doses and the effective doses during the 3D imaging increased as the phantom size increased. The effective doses for the small phantom by Monte Carlo technique were 1.9, 2.2, and 2.1 mSv for the Allura Xper FD20/10, INNOVA 4100, and AXIOM Artis dTA, respectively, while those by direct measurement were 1.6, 2.0, and 2.6 mSv. The effective doses to DAP ratios by Monte Carlo technique were 0.37-0.45, 0.26-0.32, and 0.13-0.15 (mSv Gy{sup -1}cm{sup -2}) for the Allura Xper FD20/10, INNOVA 4100, and AXIOM Artis dTA, respectively. In conclusion, the effective doses during 3D imaging and the dose-to-DAP ratios differ among angiographic units, and the effective dose can be estimated using a proper conversion factor for each angiographic unit.
Atherton, C.S.
1995-01-05T23:59:59.000Z
Two of the most important chemically reactive tropospheric gases are ozone (O{sub 3}) and the hydroxyl radical (OH). Although ozone in the stratosphere is a necessary protector against the sun`s radiation, tropospheric ozone is actually a pollutant which damages materials and vegetation, acts as a respiratory irritant, and is a greenhouse gas. One of the two main sources of ozone in the troposphere is photochemical production. The photochemistry is initiated when hydrocarbons and carbon monoxide (CO) react with nitrogen oxides (NO{sub x} = NO + NO{sub 2}) in the presence of sunlight. Reaction with the hydroxyl radical, OH, is the main sink for many tropospheric gases. The hydroxyl radical is highly reactive and has a lifetime on the order of seconds. Its formation is initiated by the photolysis of tropospheric ozone. Tropospheric chemistry involves a complex, non-linear set of chemical reactions between atmospheric species that vary substantially in time and space. To model these and other species on a global scale requires the use of a global, three-dimensional chemistry, transport, and deposition (CTD) model. In this work, I developed two such three dimensional CTD models. The first model incorporated the chemistry necessary to model tropospheric ozone production from the reactions of nitrogen oxides with carbon monoxide (CO) and methane (CH{sub 4}). The second also included longer-lived alkane species and the biogenic hydrocarbon isoprene, which is emitted by growing plants and trees. The models` ability to predict a number of key variables (including the concentration of O{sub 3}, OH, and other species) were evaluated. Then, several scenarios were simulated to understand the change in the chemistry of the troposphere since preindustrial times and the role of anthropogenic NO{sub x} on present day conditions.
The equation-transform model for Dirac–Morse problem including Coulomb tensor interaction
Ortakaya, Sami, E-mail: sami.ortakaya@yahoo.com
2013-11-15T23:59:59.000Z
The approximate solutions of Dirac equation with Morse potential in the presence of Coulomb-like tensor potential are obtained by using Laplace transform (LT) approach. The energy eigenvalue equation of the Dirac particles is found and some numerical results are obtained. By using convolution integral, the corresponding radial wave functions are presented in terms of confluent hypergeometric functions. -- Highlights: •The Dirac equation with tensor interaction is solved by using Laplace transform. •For solving this equation, we introduce the equation-transform model. •Numerical results and plots for pseudospin and spin symmetric solutions are given. •The obtained numerical results by using transform method are compared with orthogonal polynomial method.
Wurstner, S.K.; Thorne, P.D.; Chamness, M.A.; Freshley, M.D.; Williams, M.D.
1995-12-01T23:59:59.000Z
A three-dimensional numerical model of ground-water flow was developed for the uppermost unconfined aquifer at the Hanford Site in south-central Washington. Development of the model is supported by the Hanford Site Ground-Water Surveillance Project, managed by the Pacific Northwest National Laboratory, which is responsible for monitoring the sitewide movement of contaminants in ground water beneath the Hanford Site. Two objectives of the Ground-Water Surveillance Project are to (1) identify and quantify existing, emerging, or potential ground-water quality problems, and (2) assess the potential for contaminants to migrate from the Hanford Site through the ground-water pathway. Numerical models of the ground-water flow system are important tools for estimating future aquifer conditions and predicting the movement of contaminants through ground water. The Ground-Water Surveillance Project has supported development and maintenance of a two-dimensional model of the unconfined aquifer. This report describes upgrade of the two-dimensional model to a three-dimensional model. The numerical model is based on a three-dimensional conceptual model that will be continually refined and updated as additional information becomes available. This report presents a description of the three-dimensional conceptual model of ground-water flow in the unconfined aquifer system and then discusses the cur-rent state of the three-dimensional numerical model.
Warren, Oden Lee; Asif, Syed Amanulla Syed; Oh, Yunje; Feng, Yuxin; Cyrankowski, Edward; Major, Ryan
2014-09-30T23:59:59.000Z
A testing instrument for mechanical testing at nano or micron scale includes a transducer body, and a coupling shaft coupled with a probe tip. A transducer body houses a capacitor. The capacitor includes first and second counter electrodes and a center electrode assembly interposed therebetween. The center electrode assembly is movable with the coupling shaft relative to the first and second counter electrodes, for instance in one or more of dimensions including laterally and normally. The center electrode assembly includes a center plate coupled with the coupling shaft and one or more springs extending from the center plate. Upper and lower plates are coupled with the center plate and cover the center plate and the one or more springs. A shaft support assembly includes one or more support elements coupled along the coupling shaft. The shaft support assembly provides lateral support to the coupling shaft.
Three Dimensional Radiative Transfer
Tom Abel
2000-05-09T23:59:59.000Z
Radiative Transfer (RT) effects play a crucial role in the thermal history of the intergalactic medium. Here I discuss recent advances in the development of numerical methods that introduce RT to cosmological hydrodynamics. These methods can also readily be applied to time dependent problems on interstellar and galactic scales.
Afshar, Hamid R.; Naseh, Ali [School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Department of Physics, Sharif University of Technology, P.O. Box 11365-9161, Tehran (Iran, Islamic Republic of); Alishahiha, Mohsen [School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of)
2010-02-15T23:59:59.000Z
In this paper, we explore some features of f-g theory in three dimensions. We show that the theory has both anti-de Sitter and de Sitter solutions, the wave solutions in both cases are also obtained. In particular, at a critical value of the coupling constant, we see that the model admits log gravity solutions, reminiscent of topologically massive gravity and new massive gravity. We have also studied a class of exact static spherically symmetric black hole solutions in the model.
Office of Scientific and Technical Information (OSTI)
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Cole, C.R.; Wurstner, S.K.; Williams, M.D.; Thorne, P.D.; Bergeron, M.P.
1997-12-01T23:59:59.000Z
A three-dimensional numerical model of groundwater flow and transport, based on the Coupled Fluid Energy, and Solute Transport (CFEST) code, was developed for the Hanford Site to support the Hanford Groundwater Project (HGWP), managed by Pacific Northwest National Laboratory. The model was developed to increase the understanding and better forecast the migration of several contaminant plumes being monitored by the HGWP, and to support the Hanford Site Composite Analysis for low-level waste disposal in the 200-Area Plateau. Recent modeling efforts have focused on continued refinement of an initial version of the three-dimensional model developed in 1995 and its application to simulate future transport of selected contaminant plumes in the aquifer system. This version of the model was updated using a more current version of the CFEST code called CFEST96. Prior to conducting simulations of contaminant transport with the three-dimensional model, a previous steady-state, two-dimensional model of the unconfined aquifer system was recalibrated to 1979 water-table conditions with a statistical inverse method implemented in the CFEST-INV computer code. The results of the recalibration were used to refine the three-dimensional conceptual model and to calibrate it with a conceptualization that preserves the two-dimensional hydraulic properties and knowledge of the aquifer`s three-dimensional properties for the same 1979 water-table conditions. The transient behavior of the three-dimensional flow model was also calibrated by adjusting model storage properties (specific yield) until transient water-table predictions approximated observed water-table elevations between 1979 and 1996.
Ohsuka, Shinji, E-mail: ohsuka@crl.hpk.co.jp [Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakita-ku, Hamamatsu-City, 434-8601 (Japan); The Graduate School for the Creation of New Photonics Industries, 1955-1 Kurematsu-cho, Nishi-ku, Hamamatsu-City, 431-1202 (Japan); Ohba, Akira; Onoda, Shinobu; Nakamoto, Katsuhiro [Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakita-ku, Hamamatsu-City, 434-8601 (Japan); Nakano, Tomoyasu [Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakita-ku, Hamamatsu-City, 434-8601 (Japan); Ray-Focus Co. Ltd., 6009 Shinpara, Hamakita-ku, Hamamatsu-City, 434-0003 (Japan); Miyoshi, Motosuke; Soda, Keita; Hamakubo, Takao [Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan)
2014-09-15T23:59:59.000Z
We constructed a laboratory-size three-dimensional water window x-ray microscope that combines wide-field transmission x-ray microscopy with tomographic reconstruction techniques, and observed bio-medical samples to evaluate its applicability to life science research fields. It consists of a condenser and an objective grazing incidence Wolter type I mirror, an electron-impact type oxygen K? x-ray source, and a back-illuminated CCD for x-ray imaging. A spatial resolution limit of around 1.0 line pairs per micrometer was obtained for two-dimensional transmission images, and 1-?m scale three-dimensional fine structures were resolved.
Francisco Delgado
2014-10-28T23:59:59.000Z
Entanglement is considered as a basic physical resource for modern quantum applications in Quantum Information and Quantum Computation theories. Interactions able to generate and sustain entanglement are subject to deep research in order to have understanding and control on it, based on specific physical systems. Atoms, ions or quantum dots are considered a key piece in quantum applications because is a basic piece of developments towards a scalable spin-based quantum computer through universal and basic quantum operations. Ising model is a type of interaction which generates and modi?es entanglement properties of quantum systems based on matter. In this work, a general anisotropic three dimensional Ising model including an inhomogeneous magnetic field is analyzed to obtain their evolution and then, their algebraic properties which are controlled through a set of physical parameters. Evolution denote remarkable group properties when is analyzed in a non local basis, in particular those related with entanglement. These properties give a fruitful arena for further quantum applications and their control.
Ding, Y.H., E-mail: yhding@xtu.edu.cn [College of Chemical Engineering, Xiangtan University, Hunan 411105 (China); Institute of Rheology Mechanics, Xiangtan University, Hunan 411105 (China); Ren, H.M. [Institute of Rheology Mechanics, Xiangtan University, Hunan 411105 (China); Huang, Y.Y. [BTR New Energy Materials Inc., Shenzhen 518000 (China); Chang, F.H.; Zhang, P. [Institute of Rheology Mechanics, Xiangtan University, Hunan 411105 (China)
2013-10-15T23:59:59.000Z
Graphical abstract: Graphene/LiFePO{sub 4} composites as a high-performance cathode material for flexible lithium-ion batteries have been prepared by using a co-precipitation method to synthesize graphene/LiFePO4 powders as precursors and then followed by a solvent evaporation process. - Highlights: • Flexible LiFePO{sub 4}/graphene films were prepared first time by a solvent evaporation process. • The flexible electrode exhibited a high discharge capacity without conductive additives. • Graphene network offers the electrode adequate strength to withstand repeated flexing. - Abstract: Three-dimensional graphene/LiFePO{sub 4} nanostructures for flexible lithium-ion batteries were successfully prepared by solvent evaporation method. Structural characteristics of flexible electrodes were investigated by X-ray diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscopy (SEM). Electrochemical performance of graphene/LiFePO{sub 4} was examined by a variety of electrochemical testing techniques. The graphene/LiFePO{sub 4} nanostructures showed high electrochemical properties and significant flexibility. The composites with low graphene content exhibited a high capacity of 163.7 mAh g{sup ?1} at 0.1 C and 114 mAh g{sup ?1} at 5 C without further incorporation of conductive agents.
Lehmann, G.; Spatschek, K. H. [Institut für Theoretische Physik, Heinrich-Heine-Universität Düsseldorf, D-40225 Düsseldorf (Germany)] [Institut für Theoretische Physik, Heinrich-Heine-Universität Düsseldorf, D-40225 Düsseldorf (Germany)
2014-05-15T23:59:59.000Z
Ultra-intense and ultra-short laser pulses may be generated up to the exawatt-zetawatt regime due to parametric processes in plasmas. The minimization of unwanted plasma processes leads to operational limits which are discussed here with respect to filamentation. Transverse filamentation, which originally was derived for plane waves, is being investigated for seed pulse propagation in the so called ?-pulse limit. A three-dimensional (3D) three-wave-interaction model is the basis of the present investigation. To demonstrate the applicability of the three-wave-interaction model, the 1D pulse forms are compared with those obtained from 1D particle in cell and Vlasov simulations. Although wave-breaking may occur, the kinetic simulations show that the leading pumped pulse develops a form similar to that obtained from the three-wave-interaction model. In the main part, 2D and 3D filamentation processes of (localized) pulses are investigated with the three-wave-interaction model. It is shown that the leading pulse front can stay filamentation-free, whereas the rear parts show transverse modulations.
Bousbia-Salah, Anis [Universita di Pisa (Italy); Vedovi, Juswald [Pennsylvania State University (United States); D'Auria, Francesco [Universita di Pisa (Italy); Ivanov, Kostadin [Pennsylvania State University (United States); Galassi, Giorgio [Universita di Pisa (Italy)
2004-10-15T23:59:59.000Z
Thanks to continuous progress in computer technology, it is now possible to perform best-estimate simulations of complex scenarios in nuclear power plants. This method is carried out through the coupling of three-dimensional (3-D) neutron modeling of a reactor core into system codes. It is particularly appropriate for transients that involve strong interactions between core neutronics and reactor loop thermal hydraulics. For this purpose, the Peach Bottom boiling water reactor turbine trip test was selected to challenge the capability of such coupled codes. The test is characterized by a power excursion induced by rapid core pressurization and a self-limiting course behavior. In order to perform the closest simulation, the coupled thermal-hydraulic system code RELAP5 and 3-D neutron kinetic code PARCS were used. The obtained results are compared to those available from experimental data. Overall, the coupled code calculations globally predict the most significant observed aspects of the transient, such as the pressure wave amplitude across the core and the power course, with an acceptable agreement. However, sensitivity studies revealed that more-accurate code models should be considered in order to better match the void dynamic and the cross-section variations during transient conditions.
Takiwaki, Tomoya; Kotake, Kei [Center for Computational Astrophysics, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Suwa, Yudai [Yukawa Institute for Theoretical Physics, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502 (Japan)
2014-05-10T23:59:59.000Z
We present numerical results on two- (2D) and three-dimensional (3D) hydrodynamic core-collapse simulations of an 11.2 M {sub ?} star. By changing numerical resolutions and seed perturbations systematically, we study how the postbounce dynamics are different in 2D and 3D. The calculations were performed with an energy-dependent treatment of the neutrino transport based on the isotropic diffusion source approximation scheme, which we have updated to achieve a very high computational efficiency. All of the computed models in this work, including nine 3D models and fifteen 2D models, exhibit the revival of the stalled bounce shock, leading to the possibility of explosion. All of them are driven by the neutrino-heating mechanism, which is fostered by neutrino-driven convection and the standing-accretion-shock instability. Reflecting the stochastic nature of multi-dimensional (multi-D) neutrino-driven explosions, the blast morphology changes from model to model. However, we find that the final fate of the multi-D models, whether an explosion is obtained or not, is little affected by the explosion stochasticity. In agreement with some previous studies, higher numerical resolutions lead to slower onset of the shock revival in both 2D and 3D. Based on the self-consistent supernova models leading to the possibility of explosions, our results systematically show that the revived shock expands more energetically in 2D than in 3D.