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
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
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.
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
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
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.
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
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.
High-resolution ab initio Three-dimensional X-ray Diffraction Microscopy
Chapman, H N; Barty, A; Marchesini, S; Noy, A; Cui, C; Howells, M R; Rosen, R; He, H; Spence, J H; Weierstall, U; Beetz, T; Jacobsen, C; Shapiro, D
2005-08-19T23:59:59.000Z
Coherent X-ray diffraction microscopy is a method of imaging non-periodic isolated objects at resolutions only limited, in principle, by the 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 3D diffraction data using no a priori knowledge about the shape or composition of the object, which has never before been demonstrated on a non-periodic object. We also construct 2D images of thick objects with infinite depth of focus (without loss of transverse spatial resolution). These methods can be used to image biological and materials science samples at high resolution using X-ray undulator radiation, and establishes the techniques to be used in atomic-resolution ultrafast imaging at X-ray free-electron laser sources.
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.
Yao, Y. Lawrence
Proceedings of the Second International WLT-Conference on Lasers in Manufacturing 2003,Munich, June 2003 1 Process Design Of Laser Forming For Three Dimensional Thin Plates J. G. Cheng1 and Y. L. Yao2 1 Engineering, Columbia University Abstract Extensive efforts have been made in analyzing and predicting laser
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 ...
Chen, Yu
Optical coherence tomography (OCT) is an emerging medical imaging technology that enables high-resolution, noninvasive, cross-sectional imaging of microstructure in biological tissues in situ and in real time. When combined ...
Three-Dimensional Model on Thermal Response of Skin Subject to Laser Heating
Zhang, Jun
in human skin [3]. The #12;rst medical lasers were continuous beam lasers such as CO 2 laser, argon laser and Jun Zhang z Laboratory for High Performance Scienti#12;c Computing and Computer Simulation, Department to investigate the transient thermal response of human skin subject to laser heating. The temperature
Hamann, Bernd
JOURNAL OF GEOPHYSICAL RESEARCH: OCEANS, VOL. 118, 17591 , doi:10.1002/jgrc.20155, 2013 A three-dimensional eddy census of a high-resolution global ocean simulation Mark R. Petersen,1 Sean J. Williams,1,2 Mathew from a global ocean simulation with one-tenth degree resolution and a duration of 7 years. The census
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.
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.
Vertes, Akos; Nemes, Peter
2012-10-30T23:59:59.000Z
The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation with electrospray ionization (ESI).
Vertes, Akos (Reston, VA); Nemes, Peter (Silver Spring, MD)
2011-06-21T23:59:59.000Z
The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation with electrospray ionization (ESI).
Vertes, Akos; Nemes, Peter
2013-07-16T23:59:59.000Z
The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation with electrospray ionization (ESI).
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
Ultrafast-laser inscription of a three dimensional fan-out device for multicore fiber coupling
applications R. R. Thomson*, H. T. Bookey, N. D. Psaila, A. Fender, S. Campbell, W. N. MacPherson, J. S. Barton. Cerullo, G. Brown, A. Jha, and S. Shen, "Femtosecond laser inscription of optical waveguides in Bismuth). 13. R. R. Thomson, H. T. Bookey, N. Psaila, S. Campbell, D. T. Reid, S. Shen. A. Jha, A. K. Kar
Mori, Warren, B.
2012-12-01T23:59:59.000Z
We present results from the grant entitled, Ã?Â?Ã?Â¢Ã?Â?Ã?Â?Ã?Â?Ã?Â?Continuation of full-scale three-dimensional numerical experiments on high-intensity particle and laser beam-matter interactions.Ã?Â?Ã?Â¢Ã?Â?Ã?Â?Ã?Â?Ã?Â The research significantly advanced the understanding of basic high-energy density science (HEDS) on ultra intense laser and particle beam plasma interactions. This advancement in understanding was then used to to aid in the quest to make 1 GeV to 500 GeV plasma based accelerator stages. The work blended basic research with three-dimensions fully nonlinear and fully kinetic simulations including full-scale modeling of ongoing or planned experiments. The primary tool was three-dimensional particle-in-cell simulations. The simulations provided a test bed for theoretical ideas and models as well as a method to guide experiments. The research also included careful benchmarking of codes against experiment. High-fidelity full-scale modeling provided a means to extrapolate parameters into regimes that were not accessible to current or near term experiments, thereby allowing concepts to be tested with confidence before tens to hundreds of millions of dollars were spent building facilities. The research allowed the development of a hierarchy of PIC codes and diagnostics that is one of the most advanced in the world.
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 ...
Timofeev, V. I.; Smirnova, E. A., E-mail: inna@ns.crys.ras.ru [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Chupova, L. A.; Esipov, R. S. [Russian Academy of Sciences, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry (Russian Federation); Kuranova, I. P. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)
2010-11-15T23:59:59.000Z
Recombinant phosphopantetheine adenylyltransferase from Mycobacterium tuberculosis (PPAT Mt), which was produced by a high-producing strain and purified to 99%, was used for the crystal growth of the complex of the enzyme with coenzyme A (CoA). Crystals suitable for X-ray diffraction study were obtained by cocrystallization. The crystals belong to sp. gr. R32 and have the unit-cell parameters a = b = 98.840 A, c = 112.880 A, {alpha} = {beta} = 90.00{sup o}, and {gamma} = 120.00{sup o}. The three-dimensional structure of the complex was determined based on X-ray diffraction data collected from the crystals to 2.1 A resolution and refined to Rf = 22.7% and Rfree = 25.93%. Active-site bound coenzyme A was found, and its nearest environment was described. The conformational changes of the enzyme due to ligand binding were revealed. The binding of CoA by tuberculosis phosphopantetheine adenylyltransferase was characterized by comparing the structures of the title complex to a similar complex of PPAT from E. coli (PPAT Ec).
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.
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 ...
California at Davis, University of
of a high-resolution1 global ocean simulation2 Mark R. Petersen, 1 Sean J. Williams, 1,2 Mathew E. Maltrud census data set was obtained from3 a global ocean simulation with one-tenth degree resolution are at least 1000m tall, and many penetrate the14 full depth of the water column. The Antarctic Circumpolar
Wirtz, Tom; Fleming, Yves; Gerard, Mathieu [Department 'Science and Analysis of Materials' (SAM), Centre de Recherche Public, Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux (Luxembourg); Gysin, Urs; Glatzel, Thilo; Meyer, Ernst [Department of Physics, Universitaet Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Wegmann, Urs [Department of Physics, Universitaet Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Ferrovac GmbH, Thurgauerstr. 72, CH-8050 Zuerich (Switzerland); Maier, Urs [Ferrovac GmbH, Thurgauerstr. 72, CH-8050 Zuerich (Switzerland); Odriozola, Aitziber Herrero; Uehli, Daniel [SPECS Zurich GmbH, Technoparkstr. 1, CH-8005 Zuerich (Switzerland)
2012-06-15T23:59:59.000Z
State-of-the-art secondary ion mass spectrometry (SIMS) instruments allow producing 3D chemical mappings with excellent sensitivity and spatial resolution. Several important artifacts however arise from the fact that SIMS 3D mapping does not take into account the surface topography of the sample. In order to correct these artifacts, we have integrated a specially developed scanning probe microscopy (SPM) system into a commercial Cameca NanoSIMS 50 instrument. This new SPM module, which was designed as a DN200CF flange-mounted bolt-on accessory, includes a new high-precision sample stage, a scanner with a range of 100 {mu}m in x and y direction, and a dedicated SPM head which can be operated in the atomic force microscopy (AFM) and Kelvin probe force microscopy modes. Topographical information gained from AFM measurements taken before, during, and after SIMS analysis as well as the SIMS data are automatically compiled into an accurate 3D reconstruction using the software program 'SARINA,' which was developed for this first combined SIMS-SPM instrument. The achievable lateral resolutions are 6 nm in the SPM mode and 45 nm in the SIMS mode. Elemental 3D images obtained with our integrated SIMS-SPM instrument on Al/Cu and polystyrene/poly(methyl methacrylate) samples demonstrate the advantages of the combined SIMS-SPM approach.
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.
Vargas, M.; Schumaker, W.; He, Z.-H.; Zhao, Z.; Behm, K.; Chvykov, V.; Hou, B.; Krushelnick, K.; Maksimchuk, A.; Yanovsky, V.; Thomas, A. G. R., E-mail: agrt@umich.edu [Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109 (United States)
2014-04-28T23:59:59.000Z
High intensity, short pulse lasers can be used to accelerate electrons to ultra-relativistic energies via laser wakefield acceleration (LWFA) [T. Tajima and J. M. Dawson, Phys. Rev. Lett. 43, 267 (1979)]. Recently, it was shown that separating the injection and acceleration processes into two distinct stages could prove beneficial in obtaining stable, high energy electron beams [Gonsalves et al., Nat. Phys. 7, 862 (2011); Liu et al., Phys. Rev. Lett. 107, 035001 (2011); Pollock et al., Phys. Rev. Lett. 107, 045001 (2011)]. Here, we use a stereolithography based 3D printer to produce two-stage gas targets for LWFA experiments on the HERCULES laser system at the University of Michigan. We demonstrate substantial improvements to the divergence, pointing stability, and energy spread of a laser wakefield accelerated electron beam compared with a single-stage gas cell or gas jet target.
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 ...
Zhang, Shi-Chang [Research Center for Advanced Computation, Xihua University, Chengdu SC610039, China and Institute of Photoelectronics, Southwest Jiaotong University, Chengdu SC610031 (China)] [Research Center for Advanced Computation, Xihua University, Chengdu SC610039, China and Institute of Photoelectronics, Southwest Jiaotong University, Chengdu SC610031 (China)
2013-10-15T23:59:59.000Z
Analytical formulas of the Larmor rotation are derived in detail for the equilibrium electrons motion in a free-electron laser with combination of a three-dimensional (3-D) helical wiggler and a positive or a reversed guide magnetic field. Generally, the Larmor radius in the configuration of a reversed guide field is much smaller than that in a positive guide field. At non-resonance, a helical orbit governed by the zero-order component of a 3-D wiggler field could hold; meanwhile, the higher-harmonic effect definitely influences those electrons with off-axis guiding centers and induces the electron-beam spreads. At resonance, the Larmor radius in the configuration of a positive guide field has a singularity with a limit tending to infinite, which causes all the electrons to hit the waveguide wall before the exit of the wiggler. Although Larmor-radius singularity does not exist in the configuration of a reversed guide field, at anti-resonance, the first-order harmonic of a 3-D wiggler field induces a transverse displacement which rapidly grows in proportion to a square of time, and leads part of the electron beam to hit the waveguide wall before reaching the wiggler exit, which depends on the specific parameters of the individual electrons. The analytical conclusions derived in the present paper are examined by the nonlinear simulations and the experimental observation. Disagreement with the previous literatures is discussed in detail.
Three-dimensional scanning confocal laser microscope
Anderson, R. Rox (Lexington, MA); Webb, Robert H. (Lincoln, MA); Rajadhyaksha, Milind (Charlestown, MA)
1999-01-01T23:59:59.000Z
A confocal microscope for generating an image of a sample includes a first scanning element for scanning a light beam along a first axis, and a second scanning element for scanning the light beam at a predetermined amplitude along a second axis perpendicular to the first axis. A third scanning element scans the light beam at a predetermined amplitude along a third axis perpendicular to an imaging plane defined by the first and second axes. The second and third scanning element are synchronized to scan at the same frequency. The second and third predetermined amplitudes are percentages of their maximum amplitudes. A selector determines the second and third predetermined amplitudes such that the sum of the percentages is equal to one-hundred percent.
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...
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.
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.
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.
Mertens, J. C. E.; Williams, J. J.; Chawla, Nikhilesh [Materials Science and Engineering, Security and Defense Systems Initiative, Arizona State University, 781 E. Terrace Road, ISTB4, Tempe, Arizona 85287-5604 (United States)] [Materials Science and Engineering, Security and Defense Systems Initiative, Arizona State University, 781 E. Terrace Road, ISTB4, Tempe, Arizona 85287-5604 (United States)
2014-01-15T23:59:59.000Z
The design and construction of a high resolution modular x-ray computed tomography (XCT) system is described. The approach for meeting a specified set of performance goals tailored toward experimental versatility is highlighted. The instrument is unique in its detector and x-ray source configuration, both of which enable elevated optimization of spatial and temporal resolution. The process for component selection is provided. The selected components are specified, the custom component design discussed, and the integration of both into a fully functional XCT instrument is outlined. The novelty of this design is a new lab-scale detector and imaging optimization through x-ray source and detector modularity.
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.
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.
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.
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 characterization and archiving system
Clark, R.; Gallman, P.; Gaudreault, J.; Mosehauer, R.; Slotwinski, A.; Jarvis, G.; Griffiths, P.
1996-12-31T23:59:59.000Z
This system (3D-ICAS) is being developed as a remote system to perform rapid in situ analysis of hazardous organics and radionuclide contamination on structural materials. It is in the final phase of a 3-phase program to support Decontamination and Decommissioning (D&D) operations. Accurate physical characterization of surfaces and radioactive and organic contamination is a critical D&D task. Surface characterization includes identification of dangerous inorganic materials such as asbestos and transite. 3D-ICAS robotically conveys a multisensor probe near the surfaces to be inspected, using coherent laser radar tracking, which also provides 3D facility maps. High-speed automated organic analysis is provided by means of gas chromatograph-mass spectrometer sensor which can process a sample without contact in one minute. Volatile organics are extracted directly from contaminated surfaces without sample removal; multiple stage focusing is used for high time resolution. Additional discrimination is obtained through a final stage time-of-flight mass spectrometer. The radionuclide sensors combines {alpha}, {beta}, and {gamma} counting with energy discrimination of the {alpha} channel; this quantifies isotopes of U, Pu, Th, Tc, Np, and Am in one minute. The Molecular Vibrational Spectrometry sensor is used to characterize substrate material such as concrete, transite, wood, or asbestos; this can be used to provide estimates of the depth of contamination. The 3D-ICAS will be available for real-time monitoring immediately after each 1 to 2 minute sample period. After surface mapping, 3-D displays will be provided showing contours of detected contaminant concentrations. Permanent measurement and contaminant level archiving will be provided, assuring data integrity and allowing regulatory review before and after D&D operations.
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.
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.
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.
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...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
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
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.
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.
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.
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.
Three-dimensional laser micromachining and imaging of biocompatible polymers
Oldenburg, Amy
lamination [3], and 3D printing [4]. All of these methods, with the exception of melt molding, require
Three Dimensional Molecular Imaging for Lignocellulosic Materials
Bohn, Paul W.; Sweedler, Jonathan V.
2011-06-09T23:59:59.000Z
The development of high efficiency, inexpensive processing protocols to render biomass components into fermentable substrates for the sequential processing of cell wall components into fuels and important feedstocks for the biorefinery of the future is a key goal of the national roadmap for renewable energy. Furthermore, the development of such protocols depends critically on detailed knowledge of the spatial and temporal infiltration of reagents designed to remove and separate the phenylpropenoid heteropolymer (lignin) from the processable sugar components sequestered in the rigid cell walls of plants. A detailed chemical and structural understanding of this pre-enzymatic processing in space and time was the focus of this program. We worked to develop new imaging strategies that produce real-time molecular speciation information in situ; extract sub-surface information about the effects of processing; and follow the spatial and temporal characteristics of the molecular species in the matrix and correlate this complex profile with saccharification. Spatially correlated SIMS and Raman imaging were used to provide high quality, high resolution subcellular images of Miscanthus cross sections. Furthermore, the combination of information from the mass spectrometry and Raman scattering allows specific chemical assignments of observed structures, difficult to assign from either imaging approach alone and lays the foundation for subsequent heterocorrelated imaging experiments targeted at more challenging biological systems, such as the interacting plant-microbe systems relevant to the rhizosphere.
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...
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.
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.
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.
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.
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.
High resolution laser spectroscopy of cesium and rubidium molecules with optically induced coherence
Chen, Hui
2006-10-30T23:59:59.000Z
This work is devoted to the study of the quantum coherent effects in diatomic molecular systems by using high resolution laser spectroscopy. In particular, we have studied the rubidium diatomic molecular gaseous medium's absorption spectrum...
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
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.
A Steerable Laser System for Atmospheric Monitoring at the High Resolution Flys Eye
and radiometer . The energy 2 released into the sky is determined by multiplying this measurementOG 4.5.10 A Steerable Laser System for Atmospheric Monitoring at the High Resolution Flys Eye J. R. Mumford , R. C. Gray , L. R. Wiencke for the 1 1 1 High Resolution Flys Eye Collaboration 1. Physics
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.
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.
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...
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...
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.
Three Dimensioanl Free Electron Laser Dispersion Relation Including Betatron Oscillations
Chin, Y.H.
2011-01-01T23:59:59.000Z
Three-Dimensional Free Electron Laser Dispersion RelationInternational Free Electron Laser Conference, Santa Fe, NM,International Free Electron Laser Conference, held in Santa
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 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.
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.
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.
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.
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
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
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
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.
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
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.
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.
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 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.
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.
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.
Rapid Prototyping of Solid ThreeDimensional Parts
McMains, Sara
, 3D printing, fused deposition modeling, ballistic particle manufacturing, selective laser sintering : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 10 4 Fused Deposition Modeling : : : : : : : : : : : : : : : : : : : : : : : 12 5 3D Printing
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.
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.
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.
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.
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.
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.
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.
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.
Laser Doppler field sensor for high resolution flow velocity imaging without camera
Voigt, Andreas; Bayer, Christian; Shirai, Katsuaki; Buettner, Lars; Czarske, Juergen
2008-09-20T23:59:59.000Z
In this paper we present a laser sensor for highly spatially resolved flow imaging without using a camera. The sensor is an extension of the principle of laser Doppler anemometry (LDA). Instead of a parallel fringe system, diverging and converging fringes are employed. This method facilitates the determination of the tracer particle position within the measurement volume and leads to an increased spatial and velocity resolution compared to conventional LDA. Using a total number of four fringe systems the flow is resolved in two spatial dimensions and the orthogonal velocity component. Since no camera is used, the resolution of the sensor is not influenced by pixel size effects. A spatial resolution of 4 {mu}m in the x direction and 16 {mu}m in the y direction and a relative velocity resolution of 1x10{sup -3} have been demonstrated up to now. As a first application we present the velocity measurement of an injection nozzle flow. The sensor is also highly suitable for applications in nano- and microfluidics, e.g., for the measurement of flow rates.
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...
Analysis of high resolution scatter images from laser damage experiments performed on KDP
Runkel, M.; Woods, B.; Yan, M. [and others
1996-01-05T23:59:59.000Z
Interest in producing high damage threshold KH{sub 2}PO{sub 4} (KDP) and (D{sub x}H{sub 1-x}){sub 2}PO{sub 4} (KD*P, DKDP) for optical switching and frequency conversion applications is being driven by the system requirements for the National Ignition Facility (NIF) at Lawrence Livermore National Lab (LLNL). Historically, the path to achieving higher damage thresholds has been to improve the purity of crystal growth solutions. Application of advanced filtration technology has increased the damage threshold, but gives little insight into the actual mechanisms of laser damage. We have developed a laser scatter diagnostic to better study bulk defects and laser damage mechanisms in KDP and KD*P crystals. This diagnostic consists of a cavity doubled, kilohertz class, Nd:YLF laser (527 nm) and high dynamic range CCD camera which allows imaging of bulk scatter signals. With it, we have performed damage tests at 355 nm on four different {open_quotes}vintages{close_quotes} of KDP crystals, concentrating on crystals produced via fast growth methods. We compare the diagnostic`s resolution to LLNL`s standard damage detection method of 100X darkfield microscopy and discuss its impact on damage threshold determination. We have observed the disappearance of scatter sites upon exposure to subthreshold irradiation. In contrast, we have seen scatterers appear where none previously existed. This includes isolated, large (high signal) sites as well as multiple small scatter sites which appear at fluences above 7 J/cm{sup 2} (fine tracking). However, we have not observed a strong correlation of preexisting scatter sites and laser damage sites. We speculate on the connection between the laser-induced disappearance of scatter sites and the observed increase in damage threshold with laser conditioning.
Subcritical Dissipation in Three-dimensional Superflows , C. Huepe2
Nore, Caroline
the 2D one. The implications for experiments in Bose-Einstein condensed gas and low-temperature helium condensed gas by moving a blue detuned laser beam through the condensate at different velocities7 are discussed. Dilute Bose-Einstein condensates have been recently produced experimentally1 . The dynamics
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.
Prellberg, Thomas
of three-dimensional lattice trails Andrea Bedini* and Aleksander L. Owczarek Department of Mathematics
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
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
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
High-resolution multi-heterodyne spectroscopy based on Fabry-Perot quantum cascade lasers
Wang, Yin; Wang, Wen; Wysocki, Gerard, E-mail: gwysocki@princeton.edu [Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08540 (United States); Soskind, Michael G. [Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08540 (United States); Department of Electrical Engineering, Rutgers University, New Brunswick, New Jersy 08901 (United States)
2014-01-20T23:59:59.000Z
In this Letter, we present a method of performing broadband mid-infrared spectroscopy with conventional, free-running, continuous wave Fabry-Perot quantum cascade lasers (FP-QCLs). The measurement method is based on multi-heterodyne down-conversion of optical signals. The sample transmission spectrum probed by one multi-mode FP-QCL is down-converted to the radio-frequency domain through an optical multi-heterodyne process using a second FP-QCL as the local oscillator. Both a broadband multi-mode spectral measurement as well as high-resolution (?15?MHz) spectroscopy of molecular absorption are demonstrated and show great potential for development of high performance FP-laser-based spectrometers for chemical sensing.
Aramaki, Mitsutoshi [Department of Electrical Engineering and Computer Science, Nagoya University, Nagoya 464-8603 (Japan); Ogiwara, Kohei; Etoh, Shuzo [Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga 816-8580 (Japan); Yoshimura, Shinji [National Institute for Fusion Science, Toki 509-5292 (Japan); Tanaka, Masayoshi Y. [Department of Advanced Energy Engineering Science, Kyushu University, Kasuga 816-8580 (Japan)
2009-05-15T23:59:59.000Z
A high resolution laser induced fluorescence (LIF) system has been developed to measure the flow velocity field of neutral particles in an electron-cyclotron-resonance argon plasma. The flow velocity has been determined by the Doppler shift of the LIF spectrum, which is proportional to the velocity distribution function. Very high accuracy in velocity determination has been achieved by installing a saturated absorption spectroscopy unit into the LIF system, where the absolute value and scale of laser wavelength are determined by using the Lamb dip and the fringes of a Fabry-Perot interferometer. The minimum detectable flow velocity of a newly developed LIF system is {+-}2 m/s, and this performance remains unchanged in a long-time experiment. From the radial measurements of LIF spectra of argon metastable atoms, it is found that there exists an inward flow of neutral particles associated with neutral depletion.
The Three-Dimensional Structural Basis of Type II Hyperprolinemia
Srivastava, Dhiraj; Singh, Ranjan K.; Moxley, Michael A.; Henzl, Michael T.; Becker, Donald F.; Tanner, John J. (UNL); (UMC)
2012-08-31T23:59:59.000Z
Type II hyperprolinemia is an autosomal recessive disorder caused by a deficiency in {Delta}{sup 1}-pyrroline-5-carboxylate dehydrogenase (P5CDH; also known as ALDH4A1), the aldehyde dehydrogenase that catalyzes the oxidation of glutamate semialdehyde to glutamate. Here, we report the first structure of human P5CDH (HsP5CDH) and investigate the impact of the hyperprolinemia-associated mutation of Ser352 to Leu on the structure and catalytic properties of the enzyme. The 2. 5-{angstrom}-resolution crystal structure of HsP5CDH was determined using experimental phasing. Structures of the mutant enzymes S352A (2.4 {angstrom}) and S352L (2.85 {angstrom}) were determined to elucidate the structural consequences of altering Ser352. Structures of the 93% identical mouse P5CDH complexed with sulfate ion (1.3 {angstrom} resolution), glutamate (1.5 {angstrom}), and NAD{sup +} (1.5 {angstrom}) were determined to obtain high-resolution views of the active site. Together, the structures show that Ser352 occupies a hydrophilic pocket and is connected via water-mediated hydrogen bonds to catalytic Cys348. Mutation of Ser352 to Leu is shown to abolish catalytic activity and eliminate NAD{sup +} binding. Analysis of the S352A mutant shows that these functional defects are caused by the introduction of the nonpolar Leu352 side chain rather than the removal of the Ser352 hydroxyl. The S352L structure shows that the mutation induces a dramatic 8-{angstrom} rearrangement of the catalytic loop. Because of this conformational change, Ser349 is not positioned to interact with the aldehyde substrate, conserved Glu447 is no longer poised to bind NAD{sup +}, and Cys348 faces the wrong direction for nucleophilic attack. These structural alterations render the enzyme inactive.
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.
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.
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.
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.
A new TriBeam system for three-dimensional multimodal materials analysis
Echlin, McLean P.; Mottura, Alessandro; Torbet, Christopher J.; Pollock, Tresa M. [Materials Department, University of California at Santa Barbara, Santa Barbara, California 93101 (United States)
2012-02-15T23:59:59.000Z
The unique capabilities of ultrashort pulse femtosecond lasers have been integrated with a focused ion beam (FIB) platform to create a new system for rapid 3D materials analysis. The femtosecond laser allows for in situ layer-by-layer material ablation with high material removal rates. The high pulse frequency (1 kHz) of ultrashort (150 fs) laser pulses can induce material ablation with virtually no thermal damage to the surrounding area, permitting high resolution imaging, as well as crystallographic and elemental analysis, without intermediate surface preparation or removal of the sample from the chamber. The TriBeam system combines the high resolution and broad detector capabilities of the DualBeam{sup TM} microscope with the high material removal rates of the femtosecond laser, allowing 3D datasets to be acquired at rates 4-6 orders of magnitude faster than 3D FIB datasets. Design features that permit coupling of laser and electron optics systems and positioning of a stage in the multiple analysis positions are discussed. Initial in situ multilayer data are presented.
Ultrahigh performance three-dimensional electromagnetic relativistic kinetic plasma simulation
Bowers, K. J.; Albright, B. J.; Yin, L.; Bergen, B.; Kwan, T. J. T. [Plasma Theory and Applications (X-1-PTA), Los Alamos National Laboratory, MS F699, P.O. Box 1663, Los Alamos, New Mexico 87545 (United States)
2008-05-15T23:59:59.000Z
The algorithms, implementation details, and applications of VPIC, a state-of-the-art first principles 3D electromagnetic relativistic kinetic particle-in-cell code, are discussed. Unlike most codes, VPIC is designed to minimize data motion, as, due to physical limitations (including the speed of light{exclamation_point}), moving data between and even within modern microprocessors is more time consuming than performing computations. As a result, VPIC has achieved unprecedented levels of performance. For example, VPIC can perform {approx}0.17 billion cold particles pushed and charge conserving accumulated per second per processor on IBM's Cell microprocessor--equivalent to sustaining Los Alamos's planned Roadrunner supercomputer at {approx}0.56 petaflop (quadrillion floating point operations per second). VPIC has enabled previously intractable simulations in numerous areas of plasma physics, including magnetic reconnection and laser plasma interactions; next generation supercomputers like Roadrunner will enable further advances.
Visualization of high resolution, three-dimensional, nonlinear finite element analyses
Christon, M.A.; Spelce, T.E.
1992-03-24T23:59:59.000Z
A two-pass surface extraction algorithm for adaptive finite element meshes is presented in the context of a visualization study for a particle impact and a turbine containment problem. The direct use of finite element data structures for the computation of external surfaces, surface normals, and derived physical quantities is discussed. An overview of the in-betweening algorithm which compensates for rigid body dynamics is presented with a brief discussion of a {open_quotes}direct-to-videodisk{close_quotes} animation strategy.
de Jonge, Niels (Oak Ridge, TN) [Oak Ridge, TN
2010-08-17T23:59:59.000Z
A confocal scanning transmission electron microscope which includes an electron illumination device providing an incident electron beam propagating in a direction defining a propagation axis, and a precision specimen scanning stage positioned along the propagation axis and movable in at least one direction transverse to the propagation axis. The precision specimen scanning stage is configured for positioning a specimen relative to the incident electron beam. A projector lens receives a transmitted electron beam transmitted through at least part of the specimen and focuses this transmitted beam onto an image plane, where the transmitted beam results from the specimen being illuminated by the incident electron beam. A detection system is placed approximately in the image plane.
High-resolution ab initio three-dimensional X-ray diffraction microscopy (CXIDB ID 15)
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
Chapman, Henry N.
The file contains 125 images corresponding to different tilts of the sample around the y axis at 1 degree intervals. Each image is the result of 4 exposures merged together. For more details see the citation.
A Multi-Layer Three Dimensional Superconducting Nanowire Photon Detector
A. Matthew Smith
2012-02-07T23:59:59.000Z
Here we propose a new design paradigm for a superconducting nanowire single photon detector that uses a multi-layer architecture that places the electric leads beneath the nanowires. This allows for a very large number of detector elements, which we will call pixels in analogy to a conventional CCD camera, to be placed in close proximity. This leads to significantly better photon number resolution than current single and multi-nanowire meanders, while maintaining similar detection areas. We discuss the reset time of the pixels and how the design can be modified to avoid the latching failure seen in extremely short superconducting nanowires. These advantages give a multi-layer superconducting number-resolving photon detector significant advantages over the current design paradigm of long superconducting nanowire meanders. Such advantages are desirable in a wide array of photonics applications.
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.
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.
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 ...
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...
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 ...
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.
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.
Markus Herz
2005-08-23T23:59:59.000Z
Laser frequency stabilization is notably one of the major challenges on the way to a space-borne gravitational wave observatory. The proposed Laser Interferometer Space Antenna (LISA) is presently under development in an ESA, NASA collaboration. We present a novel method for active laser stabilization and phase noise suppression in such a gravitational wave detector. The proposed approach is a further evolution of the "arm locking" method, which in essence consists of using an interferometer arm as an optical cavity, exploiting the extreme long-run stability of the cavity size in the frequency band of interest. We extend this method by using the natural interferometer arm length differences and existing interferometer signals as additional information sources for the reconstruction and active suppression of the quasi-periodic laser frequency noise, enhancing the resolution power of space-borne gravitational wave detectors.
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 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.
Three-dimensional analysis of free-electron laser performance using brightness scaled variables
Gullans, M.
2008-01-01T23:59:59.000Z
to the Linac Coherent Light Source (LCLS) design, ESASEon the LCLS, and the optimal gain for a ?xed emittance.The parameters for LCLS used here are a beam energy of 13.64
Three-Dimensional Momentum Imaging of Electron Wave Packet Interference in Few-Cycle Laser Pulses
Kling, Matthias
Heidelberg, Germany A. Rudenko Max-Planck Advanced Study Group at CFEL, D-22607 Hamburg, Germany O. Herrwerth
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
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...
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
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...
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 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
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.
Suzuki, Kazuhiro; Oyabu, Noriaki; Matsushige, Kazumi; Yamada, Hirofumi [Department of Electronic Science and Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510 (Japan)] [Department of Electronic Science and Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510 (Japan); Kobayashi, Kei [The Hakubi Center for Advanced Research, Kyoto University, Katsura, Nishikyo, Kyoto 615-8520 (Japan)] [The Hakubi Center for Advanced Research, Kyoto University, Katsura, Nishikyo, Kyoto 615-8520 (Japan)
2014-02-07T23:59:59.000Z
Surface charges on nanoscale structures in liquids, such as biomolecules and nano-micelles, play an essentially important role in their structural stability as well as their chemical activities. These structures interact with each other through electric double layers (EDLs) formed by the counter ions in electrolyte solution. Although static-mode atomic force microscopy (AFM) including colloidal-probe AFM is a powerful technique for surface charge density measurements and EDL analysis on a submicron scale in liquids, precise surface charge density analysis with single-nanometer resolution has not been made because of its limitation of the resolution and the detection sensitivity. Here we demonstrate molecular-scale surface charge measurements of self-assembled micellar structures, molecular hemicylinders of sodium dodecyl sulfate (SDS), by three-dimensional (3D) force mapping based on frequency modulation AFM. The SDS hemicylindrical structures with a diameter of 4.8 nm on a graphite surface were clearly imaged. We have succeeded in visualizing 3D EDL forces on the SDS hemicylinder surfaces and obtaining the molecular-scale charge density for the first time. The results showed that the surface charge on the trench regions between the hemicylinders was much smaller than that on the hemicylinder tops. The method can be applied to a wide variety of local charge distribution studies, such as spatial charge variation on a single protein molecule.
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.
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
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.
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.
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.
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...
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
Design of a subnanometer resolution beam position monitor for dielectric laser accelerators
Byer, Robert L.
of the first laser-powered particle accel- erators "on a chip" [1,2]. These devices are specifically designed present a new concept for a beam position monitor with the unique ability to map particle beam position, this device is ideal for future x-ray sources and laser-driven particle accelerators "on a chip." Â© 2012
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.
Irfan, Bushra; Chatterjee, Ratnamala, E-mail: rmala@physics.iitd.ac.in [Department of Physics, Indian Institute of Technology Delhi (IITD), New Delhi 110016 (India); Sahoo, Satyaprakash; Gaur, Anand P. S.; Ahmadi, Majid; Katiyar, Ram S. [Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931 (United States); Guinel, Maxime J.-F. [Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931 (United States); Department of Chemistry, College of Natural Sciences, University of Puerto Rico, P.O. Box 70377, San Juan, Puerto Rico 00936-8377 (United States)
2014-05-07T23:59:59.000Z
We investigate the temperature dependent (83?K?T?523?K) frequency shift of 2A{sub g}{sup 1} and 1E{sub g}{sup 2} phonon modes in the three dimensional topological insulator Bi{sub 2}Se{sub 3}, using Raman spectroscopy. The high quality single crystals of Bi{sub 2}Se{sub 3} were grown using a modified Bridgman technique and characterized by Laue diffraction and high resolution transmission electron microscopy. A significant broadening in the line shape and red-shift in the frequencies were observed with increase in temperature. Polarized Raman scattering measurement shows a strong polarization effect of A{sub g}{sup 1} and A{sub g}{sup 2} phonon modes which confirms the good quality single crystals of Bi{sub 2}Se{sub 3}. Temperature co-efficient for A{sub 1g}{sup 1},?E{sub g}{sup 2}, and A{sub 1g}{sup 2} modes was estimated to be ?1.44?×?10{sup ?2}, ?1.94?×?10{sup ?2}, and ?1.95?×?10{sup ?2}?cm{sup ?1}?K, respectively. Our results shed light on anharmonic properties of Bi{sub 2}Se{sub 3}.
High-resolution heterodyne spectroscopy using a tunable quantum cascade laser around 3.5 THz
Ren, Y.
A frequency tunable terahertz heterodynespectrometer, based on a third-order distributed feedback quantum cascade laser as a local oscillator, has been demonstrated by measuring molecular spectral lines of methanol ...
Attosecond Resolution Timing Jitter Characterization of Diode Pumped Femtosecond Cr:Lisaf Lasers
Demirbas, Umit
Two diode pumped Cr:LiSAF lasers are synchronized using a balanced nonlinear optical cross correlator. An integrated timing jitter of less than 156 as in the 10 kHz to 10 MHz range is measured.
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.
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.
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)
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.
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.
High resolution soft x-ray spectroscopy of low Z K-shell emission from laser-produced plasmas
Dunn, J; Magee, E W; Shepherd, R; Chen, H; Hansen, S B; Moon, S J; Brown, G V; Gu, M; Beiersdorfer, P; Purvis, M A
2008-05-21T23:59:59.000Z
A large radius, R = 44.3 m, High Resolution Grating Spectrometer (HRGS) with 2400 line/mm variable line spacing has been designed for laser-produced plasma experiments conducted at the Lawrence Livermore National Laboratory Jupiter Laser Facility. The instrument has been run with a low-noise, charge-coupled device detector to record high signal-to-noise spectra in the 10-50 {angstrom} wavelength range. The instrument can be run with a 10-20 {micro}m wide slit to achieve the best spectral resolving power, approaching 1000 and similar to crystal spectrometers at 12-20 {angstrom}, or in slitless operation with a small symmetrical emission source. We describe preliminary spectra emitted from various H-like and He-like low Z ion plasmas heated by 100-500 ps (FWHM), 527 nm wavelength laser pulses. This instrument can be developed as a useful spectroscopy platform relevant to laboratory-based astrophysics as well as high energy density plasma studies.
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.
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.
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.
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 ...
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 ...
Garcia-Lechuga, M. [Departamento de Física Teórica, Atómica y Óptica, Universidad de Valladolid, 47011-Valladolid (Spain); Laser Processing Group, Instituto de Óptica “Daza de Valdés,” CSIC, 28006-Madrid (Spain); Fuentes, L. M. [Departamento de Física Aplicada, Universidad de Valladolid, 47011-Valladolid (Spain); Grützmacher, K.; Pérez, C., E-mail: concha@opt.uva.es; Rosa, M. I. de la [Departamento de Física Teórica, Atómica y Óptica, Universidad de Valladolid, 47011-Valladolid (Spain)
2014-10-07T23:59:59.000Z
We report a detailed characterization of the spatial resolution provided by two-photon absorption spectroscopy suited for plasma diagnosis via the 1S-2S transition of atomic hydrogen for optogalvanic detection and laser induced fluorescence (LIF). A precise knowledge of the spatial resolution is crucial for a correct interpretation of measurements, if the plasma parameters to be analysed undergo strong spatial variations. The present study is based on a novel approach which provides a reliable and realistic determination of the spatial resolution. Measured irradiance distribution of laser beam waists in the overlap volume, provided by a high resolution UV camera, are employed to resolve coupled rate equations accounting for two-photon excitation, fluorescence decay and ionization. The resulting three-dimensional yield distributions reveal in detail the spatial resolution for optogalvanic and LIF detection and related saturation due to depletion. Two-photon absorption profiles broader than the Fourier transform-limited laser bandwidth are also incorporated in the calculations. The approach allows an accurate analysis of the spatial resolution present in recent and future measurements.
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...
A Genetic Algorithm for Packing ThreeDimensional NonConvex Objects Having Cavities and Holes
Coello, Carlos A. Coello
packing, non convex objects, selective laser sintering, rapid proto typing 1 INTRODUCTION 1.1 SELECTIVE, the selective laser sintering (SLS) machine produces parts directly from CAD files through an additive manufac tions of parts at each layer. Selective laser sintering uses fine, heatfusible powder to build a part
Sub 400 nm spatial resolution extreme ultraviolet holography with a table top laser
Rocca, Jorge J.
. J. E. Trebes, S. B. Brown, E. M. Campbell, D. L. Matthews, D. G. Nilson, G. F. Stone, and D. A Society of America OCIS codes: (090.0090) Holography; (100.2960) Image analysis References and Links 1. D, C. Jacobsen, E. Anderson, M. R. Howells, and D. P. Kern, "High resolution imaging by Fourier
Lyra, Wladimir; Mac Low, Mordecai-Mark, E-mail: wlyra@jpl.nasa.gov, E-mail: mordecai@amnh.org [Department of Astrophysics, American Museum of Natural History, 79th Street at Central Park West, New York, NY 10024 (United States)
2012-09-01T23:59:59.000Z
It has been suggested that the transition between magnetorotationally active and dead zones in protoplanetary disks should be prone to the excitation of vortices via Rossby wave instability (RWI). However, the only numerical evidence for this has come from alpha disk models, where the magnetic field evolution is not followed, and the effect of turbulence is parameterized by Laplacian viscosity. We aim to establish the phenomenology of the flow in the transition in three-dimensional resistive-magnetohydrodynamical models. We model the transition by a sharp jump in resistivity, as expected in the inner dead zone boundary, using the PENCIL CODE to simulate the flow. We find that vortices are readily excited in the dead side of the transition. We measure the mass accretion rate finding similar levels of Reynolds stress at the dead and active zones, at the {alpha} Almost-Equal-To 10{sup -2} level. The vortex sits in a pressure maximum and does not migrate, surviving until the end of the simulation. A pressure maximum in the active zone also triggers the RWI. The magnetized vortex that results should be disrupted by parasitical magneto-elliptic instabilities, yet it subsists in high resolution. This suggests that either the parasitic modes are still numerically damped or that the RWI supplies vorticity faster than they can destroy it. We conclude that the resistive transition between the active and dead zones in the inner regions of protoplanetary disks, if sharp enough, can indeed excite vortices via RWI. Our results lend credence to previous works that relied on the alpha-disk approximation, and caution against the use of overly reduced azimuthal coverage on modeling this transition.
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.
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.
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.
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 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.
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.
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.
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.
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.
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.
Walter, Nils G.
-dimensional (3D) pathway taken by mRNPs as they transit through the NPC, and the kinetics and selectivity. A 3D reconstruction of the export route indicates that mRNPs primarily interact with the periphery to facilitate mRNP export by interacting with the FG Nups22,23. After shuttling through the NPC, m
High-resolution adaptive optics scanning laser ophthalmoscope with multiple deformable mirrors
Chen, Diana C. (Fremont, CA); Olivier, Scot S. (Livermore, CA); Jones; Steven M. (Livermore, CA)
2010-02-23T23:59:59.000Z
An adaptive optics scanning laser ophthalmoscopes is introduced to produce non-invasive views of the human retina. The use of dual deformable mirrors improved the dynamic range for correction of the wavefront aberrations compared with the use of the MEMS mirror alone, and improved the quality of the wavefront correction compared with the use of the bimorph mirror alone. The large-stroke bimorph deformable mirror improved the capability for axial sectioning with the confocal imaging system by providing an easier way to move the focus axially through different layers of the retina.
Sensors and Actuators A 127 (2006) 228234 Fabrication of three-dimensional microstructures based on
2006-01-01T23:59:59.000Z
laser system. Compared to existing manufacturing techniques, our direct UV laser writing method greatly Zhanga, a Department of Manufacturing Engineering, Boston University, 15 Saint Mary's Street, Boston, MA Available online 3 October 2005 Abstract This paper introduces a novel 3D manufacturing approach
attached three-dimensional turbulent: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
resolutions up to 5123. We show that at varying the spectrum slope y, small-scale turbulent fluctuations change from a it forcing independent to a it forcing...
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.
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.
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.
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.
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.
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.
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/.
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.
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.
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.
Martin, Madhavi Z [ORNL; Labbe, Nicole [ORNL; Wagner, Rebekah J. [Pennsylvania State University, University Park, PA
2013-01-01T23:59:59.000Z
This chapter details the application of LIBS in a number of environmental areas of research such as carbon sequestration and climate change. LIBS has also been shown to be useful in other high resolution environmental applications for example, elemental mapping and detection of metals in plant materials. LIBS has also been used in phytoremediation applications. Other biological research involves a detailed understanding of wood chemistry response to precipitation variations and also to forest fires. A cross-section of Mountain pine (pinceae Pinus pungen Lamb.) was scanned using a translational stage to determine the differences in the chemical features both before and after a fire event. Consequently, by monitoring the elemental composition pattern of a tree and by looking for abrupt changes, one can reconstruct the disturbance history of a tree and a forest. Lastly we have shown that multivariate analysis of the LIBS data is necessary to standardize the analysis and correlate to other standard laboratory techniques. LIBS along with multivariate statistical analysis makes it a very powerful technology that can be transferred from laboratory to field applications with ease.
Kim, Daekeun, Ph. D. Massachusetts Institute of Technology
2009-01-01T23:59:59.000Z
The availability of lasers with femtosecond, ultrafast light pulses provides new opportunities and challenges in instrument design. This thesis addresses three aspects of utilizing ultrafast light pulses in two-photon ...
Advances in three-dimensional rapid prototyping of microfluidic devices for biological applications
Chang, Hsueh-Chia
. #12;2 Abstract The capability of 3D printing technologies for direct production of complex 3D 3D printing technologies and direct internal 3D laser writing fabrication methods. Current
Matsuo, K. [Fukuoka Institute of Technology, Fukuoka 811-0295 (Japan); Iguchi, H.; Okamura, S.; Matsuoka, K. [National Institute for Fusion Science, Toki 509-5292 (Japan)
2012-01-15T23:59:59.000Z
Laser phase contrast is a powerful diagnostic method to determine the spatial distribution of electron density fluctuations in magnetically confined plasmas, although its applicability depends on magnetic field configurations. The spatial resolution of fluctuations is linked with the resolution of the propagation direction that is derived from the two-dimensional spectral analysis of the wavenumber for the fluctuations. The method was applied to fluctuation measurements in a compact helical system. In order to improve the resolution of the propagation direction with a relatively small number of data points, the maximum entropy method with polar coordinates was employed. A spatial resolution of the order of 1 cm was obtained, which is satisfactory in a plasma with a 20 cm minor radius.
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
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
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
Malinauskas, M.; Purlys, V.; Zukauskas, A.; Rutkauskas, M.; Danilevicius, P.; Paipulas, D.; Bickauskaite, G.; Gadonas, R.; Piskarskas, A. [Vilnius University, Physics Faculty, Department of Quantum Electronics, Laser Research Center, Sauletekio ave. 10, LT-10223 Vilnius (Lithuania); Bukelskis, L.; Baltriukiene, D.; Bukelskiene, V. [Institute of Biochemistry, Vivarium, Mokslininkuo str. 12, LT-08662 Vilnius (Lithuania); Sirmenis, R. [Vilnius University Hospital Santariskiuo Klinikos, Santariskiuo g. 2, LT-08661 Vilnius (Lithuania); Gaidukeviciute, A. [Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, Vassilika Vouton, 711 10 Heraklion, Crete (Greece); Sirvydis, V. [Vilnius University, Faculty of Medicine, Heart Surgery Center, Santariskiuo 2, LT-08661, Vilnius (Lithuania)
2010-11-10T23:59:59.000Z
We present a femtosecond Laser Two-Photon Polymerization (LTPP) system of large scale three-dimensional structuring for applications in tissue engineering. The direct laser writing system enables fabrication of artificial polymeric scaffolds over a large area (up to cm in lateral size) with sub-micrometer resolution which could find practical applications in biomedicine and surgery. Yb:KGW femtosecond laser oscillator (Pharos, Light Conversion. Co. Ltd.) is used as an irradiation source (75 fs, 515 nm (frequency doubled), 80 MHz). The sample is mounted on wide range linear motor driven stages having 10 nm sample positioning resolution (XY--ALS130-100, Z--ALS130-50, Aerotech, Inc.). These stages guarantee an overall travelling range of 100 mm into X and Y directions and 50 mm in Z direction and support the linear scanning speed up to 300 mm/s. By moving the sample three-dimensionally the position of laser focus in the photopolymer is changed and one is able to write complex 3D (three-dimensional) structures. An illumination system and CMOS camera enables online process monitoring. Control of all equipment is automated via custom made computer software ''3D-Poli'' specially designed for LTPP applications. Structures can be imported from computer aided design STereoLihography (stl) files or programmed directly. It can be used for rapid LTPP structuring in various photopolymers (SZ2080, AKRE19, PEG-DA-258) which are known to be suitable for bio-applications. Microstructured scaffolds can be produced on different substrates like glass, plastic and metal. In this paper, we present microfabricated polymeric scaffolds over a large area and growing of adult rabbit myogenic stem cells on them. Obtained results show the polymeric scaffolds to be applicable for cell growth practice. It exhibit potential to use it for artificial pericardium in the experimental model in the future.
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.
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.
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.
Berlin,Technische Universität
1 Modeling of Laser Cutting and Related Processes A considerable proportion of laser processing. Modeling laser cutting and its features Recent modeling work has concentrated on the implementation and numerical evaluation of a transient three-dimensional computer simulation of the CO2 laser cutting process
Zhang, Yuwen
heat conduction Laser Gaussian profile Conjugate gradient method a b s t r a c t Temperature and heat gradient method Jianhua Zhou, Yuwen Zhang *, J.K. Chen, Z.C. Feng Department of Mechanical and Aerospace gradient method (CGM) with temperature and heat flux measured on back surface (opposite to the heated
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.
THREE-DIMENSIONAL CLOUD STRUCTURE OBSERVED DURING DOE ARM'S 2009 CLOUD TOMOGRAPHY FIELD EXPERIMENT
vapor. During the Summer of 2009, five scanning microwave radiometers were deployed along an eight conditions. The high-resolution tomographic retrievals provide a unique opportunity for investigating Associates, LLC under Contract No. DE-AC02- 98CH10886 with the U.S. Department of Energy. The publisher
Self-assembled three-dimensional conducting network of single-wall carbon nanotubes
Hone, James
- resolution printing of devices over large areas while provid- ing a low-cost path toward the early American Institute of Physics. [DOI: 10.1063/1.1776619] There is considerable interest in the fabrication path for the fabrication of wires for nano- electronics. The synthesis of a material satisfying
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.
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.
Mass, Clifford F.
-Resolution Weather Prediction?4 5 Clifford F. Mass1 and Luke E. Madaus6 Department of Atmospheric Sciences7 1 Corresponding author Professor Clifford F. Mass Department of Atmospheric Sciences Box 351640 about three-dimensional55 atmosph
Turbulence in a three-dimensional deflagration model for Type Ia supernovae: I. Scaling properties
Ciaraldi-Schoolmann, F; Niemeyer, J C; Roepke, F K; Hillebrandt, W
2009-01-01T23:59:59.000Z
We analyze the statistical properties of the turbulent velocity field in the deflagration model for Type Ia supernovae. In particular, we consider the question of whether turbulence is isotropic and consistent with the Kolmogorov theory at small length scales. Using numerical data from a high-resolution simulation of a thermonuclear supernova explosion, spectra of the turbulence energy and velocity structure functions are computed. We show that the turbulent velocity field is isotropic at small length scales and follows a scaling law that is consistent with the Kolmogorov theory until most of the nuclear fuel is burned. At length scales greater than a certain characteristic scale, turbulence becomes anisotropic. Here, the radial velocity fluctuations follow the scaling law of the Rayleigh-Taylor instability, whereas the angular component still obeys Kolmogorov scaling. In the late phase of the explosion, this characteristic scale drops below the numerical resolution of the simulation. The analysis confirms th...
Goyal, Amit (Knoxville, TN), Kang; Sukill (Knoxville, TN)
2012-02-21T23:59:59.000Z
Novel articles and methods to fabricate same with self-assembled nanodots and/or nanorods of a single or multicomponent material within another single or multicomponent material for use in electrical, electronic, magnetic, electromagnetic and electrooptical devices is disclosed. Self-assembled nanodots and/or nanorods are ordered arrays wherein ordering occurs due to strain minimization during growth of the materials. A simple method to accomplish this when depositing in-situ films is also disclosed. Device applications of resulting materials are in areas of superconductivity, photovoltaics, ferroelectrics, magnetoresistance, high density storage, solid state lighting, non-volatile memory, photoluminescence, thermoelectrics and in quantum dot lasers.
Goyal, Amit
2013-09-17T23:59:59.000Z
Novel articles and methods to fabricate same with self-assembled nanodots and/or nanorods of a single or multicomponent material within another single or multicomponent material for use in electrical, electronic, magnetic, electromagnetic and electrooptical devices is disclosed. Self-assembled nanodots and/or nanorods are ordered arrays wherein ordering occurs due to strain minimization during growth of the materials. A simple method to accomplish this when depositing in-situ films is also disclosed. Device applications of resulting materials are in areas of superconductivity, photovoltaics, ferroelectrics, magnetoresistance, high density storage, solid state lighting, non-volatile memory, photoluminescence, thermoelectrics and in quantum dot lasers.
Three dimensional simulations of Richtmyer-Meshkov instabilities in shock-tube experiments
Gowardhan, Akshay A [Los Alamos National Laboratory; Grinstein, Fernando F [Los Alamos National Laboratory; Wachtor, Adam J [Los Alamos National Laboratory
2010-01-01T23:59:59.000Z
In the large eddy simulation (LES) approach large-scale energy-containing structures are resolved, smaller (presumably) more isotropic structures are filtered out, and unresolved subgrid effects are modeled. Extensive recent work has demonstrated that predictive simulations of turbulent velocity fields are possible based on subgrid scale modeling implicitly provided by a class of high-resolution finite-volume algorithms. This strategy is called implicit LES. The extension of the approach to the substantially more difficult problem of material mixing IS addressed, and progress in representative shock-driven turbulent mixing studies is reported.
Xiao, Qingmei; Li, Cong; Hai, Ran; Zhang, Lei; Feng, Chunlei; Ding, Hongbin, E-mail: hding@dlut.edu.cn [School of Physics and Optical Electronic Technology, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024 (China); Zhou, Yan; Yan, Longwen; Duan, Xuru [Southwestern Institute of Physics, P.O. Box 432, No. 3 South Section 3, Circle Road 2, Chengdu 610041, Sichuan (China)
2014-05-15T23:59:59.000Z
A laser ablation microprobe time-of-flight mass spectroscopy (LAM-TOF-MS) system with high spatial resolution, ?20 nm in depth and ?500 ?m or better on the surface, is developed to analyze the composition distributions of deposition layers on the first wall materials or first mirrors in tokamak. The LAM-TOF-MS system consists of a laser ablation microprobe combined with a TOF-MS and a data acquisition system based on a LabVIEW program software package. Laser induced ablation combined with TOF-MS is an attractive method to analyze the depth profile of deposited layer with successive laser shots, therefore, it can provide information for composition reconstruction of the plasma wall interaction process. In this work, we demonstrate that the LAM-TOF-MS system is capable of characterizing the depth profile as well as mapping 2D composition of deposited film on the molybdenum first mirror retrieved from HL-2A tokamak, with particular emphasis on some of the species produced during the ablation process. The presented LAM-TOF-MS system provides not only the 3D characterization of deposition but also the removal efficiency of species of concern.
Three-Dimensional EBSD Analysis of YSZ, NiO-YSZ and Ni-Alloy
Saraf, Laxmikant V.
2012-01-03T23:59:59.000Z
In this report, a method is discussed to perform successive milling on yttria-stabilized zirconia (YSZ), NiO-YSZ and Ni-alloy at the intervals of 85 nm 50 nm and 100 nm, respectively using a focused ion beam (FIB) followed by electron backscatter diffraction (EBSD) analysis on each slice. The EBSD data is then reconstructed to generate 3D volume. The 3D-EBSD band quality data is superimposed on inverse pole figure (IPF) grain orientation analysis to get a correlation with quality of band indexing. For the NiO-YSZ case, grain orientations and band quality factors were matched for grains {approx}250 nm diameters producing a high resolution 3D-EBSD data. For this case, a pore space in 3D volume was visible due to nanocrystalline NiO-YSZ grain network. The advantages of 3D EBSD are discussed in the context of its applications to SOFC research community.
Three-dimensional foam flow resolved by fast X-ray tomographic microscopy
Raufaste, Christophe; Mader, Kevin; Santucci, Stéphane; Mokso, Rajmund
2015-01-01T23:59:59.000Z
Thanks to ultra fast and high resolution X-ray tomography, we managed to capture the evolution of the local structure of the bubble network of a 3D foam flowing around a sphere. As for the 2D foam flow around a circular obstacle, we observed an axisymmetric velocity field with a recirculation zone, and indications of a negative wake downstream the obstacle. The bubble deformations, quantified by a shape tensor, are smaller than in 2D, due to a purely 3D feature: the azimuthal bubble shape variation. Moreover, we were able to detect plastic rearrangements, characterized by the neighbor-swapping of four bubbles. Their spatial structure suggest that rearrangements are triggered when films faces get smaller than a characteristic area.
Three-dimensional foam flow resolved by fast X-ray tomographic microscopy
Christophe Raufaste; Benjamin Dollet; Kevin Mader; Stéphane Santucci; Rajmund Mokso
2015-03-19T23:59:59.000Z
Thanks to ultra fast and high resolution X-ray tomography, we managed to capture the evolution of the local structure of the bubble network of a 3D foam flowing around a sphere. As for the 2D foam flow around a circular obstacle, we observed an axisymmetric velocity field with a recirculation zone, and indications of a negative wake downstream the obstacle. The bubble deformations, quantified by a shape tensor, are smaller than in 2D, due to a purely 3D feature: the azimuthal bubble shape variation. Moreover, we were able to detect plastic rearrangements, characterized by the neighbor-swapping of four bubbles. Their spatial structure suggest that rearrangements are triggered when films faces get smaller than a characteristic area.
Three-Dimensional Simulations of SASI- and Convection-Dominated Core-Collapse Supernovae
Fernández, Rodrigo
2015-01-01T23:59:59.000Z
We investigate the effect of dimensionality on the transition to explosion in neutrino-driven core-collapse supernovae. Using parameterized hydrodynamic simulations of the stalled supernova shock in one-, two- (2D), and three spatial dimensions (3D), we systematically probe the extent to which hydrodynamic instabilities alone can tip the balance in favor of explosion. In particular, we focus on systems that are well into the regimes where the Standing Accretion Shock Instability (SASI) or neutrino-driven convection dominate the dynamics, and characterize the difference between them. We find that SASI-dominated models can explode with up to ~20% lower neutrino luminosity in 3D than in 2D, with the magnitude of this difference decreasing with increasing resolution. This improvement in explosion conditions originates in the ability of spiral modes to generate more non-radial kinetic energy than a single sloshing mode, increasing the size of the average shock radius, and hence generating better conditions for the...
Three-dimensional gravity modeling and focusing inversion using rectangular meshes.
Commer, M.
2011-03-01T23:59:59.000Z
Rectangular grid cells are commonly used for the geophysical modeling of gravity anomalies, owing to their flexibility in constructing complex models. The straightforward handling of cubic cells in gravity inversion algorithms allows for a flexible imposition of model regularization constraints, which are generally essential in the inversion of static potential field data. The first part of this paper provides a review of commonly used expressions for calculating the gravity of a right polygonal prism, both for gravity and gradiometry, where the formulas of Plouff and Forsberg are adapted. The formulas can be cast into general forms practical for implementation. In the second part, a weighting scheme for resolution enhancement at depth is presented. Modelling the earth using highly digitized meshes, depth weighting schemes are typically applied to the model objective functional, subject to minimizing the data misfit. The scheme proposed here involves a non-linear conjugate gradient inversion scheme with a weighting function applied to the non-linear conjugate gradient scheme's gradient vector of the objective functional. The low depth resolution due to the quick decay of the gravity kernel functions is counteracted by suppressing the search directions in the parameter space that would lead to near-surface concentrations of gravity anomalies. Further, a density parameter transformation function enabling the imposition of lower and upper bounding constraints is employed. Using synthetic data from models of varying complexity and a field data set, it is demonstrated that, given an adequate depth weighting function, the gravity inversion in the transform space can recover geologically meaningful models requiring a minimum of prior information and user interaction.
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.
MRI Investigations of Particle Motion within a Three-Dimensional Vibro-Fluidized Granular Bed
Mick D. Mantle; Andrew J. Sederman; Lynn F. Gladden; Jonathan M. Huntley; Tom W. Martin Ricky D. Wildman; Mark D. Shattuck
2007-02-08T23:59:59.000Z
The unique ability of magnetic resonance imaging (MRI) to provide spatial and temporal information from optically opaque systems, in three dimensions, make it an ideal tool to study the internal motion of rapid granular flows. This paper will focus on the use of ultra-fast velocity compensated MRI measurements to study particle velocity and density distributions in a granular gas, produced by vibrating vertically a bed of mustard seeds at 40 Hz. Specifically, a velocity compensated, double spin-echo, triggered, one-dimensional MRI profiling pulse sequence was developed. This gives an MRI temporal resolution of approximately 2 ms and also minimises MRI velocity artefacts. 12 phase measurements per vibration cycle were used. The data can be used to extract values of the mustard seed average velocity and velocity propagators (probability distributions functions) as a function of the phase of the vibration cycle and vertical height within the cell. The data show strong transient effects during the impact phase of the vibration. A detailed discussion of the temporal passage of the individual phase resolved, height resolved velocity distributions, along with seed velocity propagators at a fix height from the vibrating base is presented.
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.
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 ...
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 Imaging and Quantification of Biomass and Biofilms in Porous Media
Dorthe Wildenschild
2012-10-10T23:59:59.000Z
A new method to resolve biofilms in three dimensions in porous media using high-resolution synchrotron-based x-ray computed microtomography (CMT) has been developed. Imaging biofilms in porous media without disturbing the natural spatial arrangement of the porous media and associated biofilm has been a challenging task, primarily because porous media generally precludes conventional imaging via optical microscopy; x-ray tomography offers a potential alternative. One challenge for using this method is that most conventional x-ray contrast agents are water-soluble and easily diffuse into biofilms. To overcome this problem, silver-coated microspheres were added to the fluid phase to create an x-ray contrast that does not diffuse into the biofilm mass. Using this approach, biofilm imaging in porous media was accomplished with sufficient contrast to differentiate between the biomass- and fluid-filled pore spaces. The method was validated by using a two-dimensional micro-model flow cell where both light microscopy and CMT imaging were used to im age the biofilm. The results of this work has been published in Water Resources Research (Iltis et al., 2010). Additional work needs to be done to optimize this imaging approach, specifically, we find that the quality of the images are highly dependent on the coverage of the biofilm with Ag particles, - which means that we may have issues in dead-end pore space and for very low density (fluffy) biofilms. What we can image for certain with this technique is the biofilm surface that is well-connected to flow paths and thus well-supplied with nutrients etc.
Anomalous critical behaviour in the polymer collapse transition of three-dimensional lattice trails
Andrea Bedini; Aleksander L Owczarek; Thomas Prellberg
2011-11-11T23:59:59.000Z
Trails (bond-avoiding walks) provide an alternative lattice model of polymers to self-avoiding walks, and adding self-interaction at multiply visited sites gives a model of polymer collapse. Recently, a two-dimensional model (triangular lattice) where doubly and triply visited sites are given different weights was shown to display a rich phase diagram with first and second order collapse separated by a multi-critical point. A kinetic growth process of trails (KGT) was conjectured to map precisely to this multi-critical point. Two types of low temperature phases, globule and crystal-like, were encountered. Here, we investigate the collapse properties of a similar extended model of interacting lattice trails on the simple cubic lattice with separate weights for doubly and triply visited sites. Again we find first and second order collapse transitions dependent on the relative sizes of the doubly and triply visited energies. However we find no evidence of a low temperature crystal-like phase with only the globular phase in existence. Intriguingly, when the ratio of the energies is precisely that which separates the first order from the second-order regions anomalous finite-sized scaling appears. At the finite size location of the rounded transition clear evidence exists for a first order transition that persists in the thermodynamic limit. This location moves as the length increases, with its limit apparently at the point that maps to a KGT. However, if one fixes the temperature to sit at exactly this KGT point then only a critical point can be deduced from the data. The resolution of this apparent contradiction lies in the breaking of crossover scaling and the difference in the shift and transition width (crossover) exponents.
Ren, Lei, E-mail: lren1@hfhs.org [Department of Radiation Oncology, Henry Ford Health System, Detroit, MI (United States); Chetty, Indrin J. [Department of Radiation Oncology, Henry Ford Health System, Detroit, MI (United States); Zhang Junan [Department of Radiation Oncology, Oregon Health and Science University, Portland, OR (United States); Jin Jianyue [Department of Radiation Oncology, Henry Ford Health System, Detroit, MI (United States); Wu, Q. Jackie; Yan Hui; Brizel, David M.; Lee, W. Robert [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Movsas, Benjamin [Department of Radiation Oncology, Henry Ford Health System, Detroit, MI (United States); Yin Fangfang [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States)
2012-04-01T23:59:59.000Z
Purpose: To develop a three-dimensional (3D) cone-beam computed tomography (CBCT) estimation method using a deformation field map, and to evaluate and optimize the efficiency and accuracy of the method for use in the clinical setting. Methods and Materials: We propose a method to estimate patient CBCT images using prior information and a deformation model. Patients' previous CBCT data are used as the prior information, and the new CBCT volume to be estimated is considered as a deformation of the prior image volume. The deformation field map is solved by minimizing deformation energy and maintaining new projection data fidelity using a nonlinear conjugate gradient method. This method was implemented in 3D form using hardware acceleration and multi-resolution scheme, and it was evaluated for different scan angles, projection numbers, and scan directions using liver, lung, and prostate cancer patient data. The accuracy of the estimation was evaluated by comparing the organ volume difference and the similarity between estimated CBCT and the CBCT reconstructed from fully sampled projections. Results: Results showed that scan direction and number of projections do not have significant effects on the CBCT estimation accuracy. The total scan angle is the dominant factor affecting the accuracy of the CBCT estimation algorithm. Larger scan angles yield better estimation accuracy than smaller scan angles. Lung cancer patient data showed that the estimation error of the 3D lung tumor volume was reduced from 13.3% to 4.3% when the scan angle was increased from 60 Degree-Sign to 360 Degree-Sign using 57 projections. Conclusions: The proposed estimation method is applicable for 3D DTS, 3D CBCT, four-dimensional CBCT, and four-dimensional DTS image estimation. This method has the potential for significantly reducing the imaging dose and improving the image quality by removing the organ distortion artifacts and streak artifacts shown in images reconstructed by the conventional Feldkamp-Davis-Kress (FDK) algorithm.
Patel, Sangita B.; Cameron, Patricia M.; O'Keefe, Stephen J.; Frantz-Wattley, Betsy; Thompson, Jed; O'Neill, Edward A.; Tennis, Trevor; Liu, Luping; Becker, Joseph W.; Scapin, Giovanna; Merck
2010-10-18T23:59:59.000Z
The p38 mitogen-activated protein kinases are activated in response to environmental stress and cytokines and play a significant role in transcriptional regulation and inflammatory responses. Of the four p38 isoforms known to date, two (p38{alpha} and p38{beta}) have been identified as targets for cytokine-suppressive anti-inflammatory drugs. Recently, it was reported that specific inhibition of the p38{alpha} isoform is necessary and sufficient for anti-inflammatory efficacy in vivo, while further inhibition of p38{beta} may not provide any additional benefit. In order to aid the development of p38{alpha}-selective compounds, the three-dimensional structure of p38{beta} was determined. To do so, the C162S and C119S,C162S mutants of human MAP kinase p38{beta} were cloned, expressed in Escherichia coli and purified. Initial screening hits in crystallization trials in the presence of an inhibitor led upon optimization to crystals that diffracted to 2.05 {angstrom} resolution and allowed structure determination (PDB codes 3gc8 and 3gc9 for the single and double mutant, respectively). The structure of the p38{alpha} C162S mutant in complex with the same inhibitor is also reported (PDB code 3gc7). A comparison between the structures of the two kinases showed that they are highly similar overall but that there are differences in the relative orientation of the N- and C-terminal domains that causes a reduction in the size of the ATP-binding pocket in p38{beta}. This difference in size between the two pockets could be exploited in order to achieve selectivity.
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
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.
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.
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.
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.
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.
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)].
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.