A Bme Solution Of The Stochastic Three-Dimensional Laplace Equation...
Solution Of The Stochastic Three-Dimensional Laplace Equation Representing A Geothermal Field Subject To Site-Specific Information Abstract This work develops a model of the...
Numerical solution of three-dimensional magnetic differential equations
Reiman, A.H.; Greenside, H.S.
1987-02-01
A computer code is described that solves differential equations of the form B . del f = h for a single-valued solution f, given a toroidal three-dimensional divergence-free field B and a single-valued function h. The code uses a new algorithm that Fourier decomposes a given function in a set of flux coordinates in which the field lines are straight. The algorithm automatically adjusts the required integration lengths to compensate for proximity to low order rational surfaces. Applying this algorithm to the Cartesian coordinates defines a transformation to magnetic coordinates, in which the magnetic differential equation can be accurately solved. Our method is illustrated by calculating the Pfirsch-Schlueter currents for a stellarator.
Expansion solution of Laplace`s equation: Technique and application to hollow beam gun design
Jackson, R.H.; Taccetti, J.M.
1996-12-31
This paper presents a flexible algorithm for the general calculation of expansion solutions to Laplace`s equation. The limiting factor in application of the technique is shown to be series truncation error and not errors in calculating numerical derivatives. Application of the algorithm to the accurate computation of arbitrary magnetic fields in cylindrical geometry from on-axis or coil data will be presented. For an ideal current loop, magnetic field accuracies of better than 0.01% of the exact elliptic integral solution can be obtained out to approximately 70--80% of the loop radius. Accuracy improves dramatically for radii closer to the axis. Results also is shown for thin current disks, thin solenoids and thick coils. Other aspects of the technique is illustrated by application to the design of a coil system for a hollow beam electron gun. With some reasonable assumptions about the overlay of the electron trajectories and the magnetic flux contours, it is possible to generate an estimate for the on-axis profile of the gun magnetic field. The expansion technique can then be applied to calculate the off-axis field and its impact on the trajectories without assuming any particular coil system. The initial estimate can then be refined and retested. Finally, an optimization technique is used to develop a coil system which closely reproduces the refined field. The results of carrying out this set of calculations on a 150 kV, 20 A hollow electron gun design for an FEL experiment is reported.
Three-dimensional nonlinear Schroedinger equation in electron-positron-ion magnetoplasmas
Sabry, R.; Moslem, W. M.; El-Shamy, E. F.; Shukla, P. K.
2011-03-15
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.
Waltz, J.; Canfield, T.R.; Morgan, N.R.; Risinger, L.D.; Wohlbier, J.G.
2014-06-15
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 Rayleighâ€“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.
Shao, Yan-Lin Faltinsen, Odd M.
2014-10-01
We propose a new efficient and accurate numerical method based on harmonic polynomials to solve boundary value problems governed by 3D Laplace equation. The computational domain is discretized by overlapping cells. Within each cell, the velocity potential is represented by the linear superposition of a complete set of harmonic polynomials, which are the elementary solutions of Laplace equation. By its definition, the method is named as Harmonic Polynomial Cell (HPC) method. The characteristics of the accuracy and efficiency of the HPC method are demonstrated by studying analytical cases. Comparisons will be made with some other existing boundary element based methods, e.g. Quadratic Boundary Element Method (QBEM) and the Fast Multipole Accelerated QBEM (FMA-QBEM) and a fourth order Finite Difference Method (FDM). To demonstrate the applications of the method, it is applied to some studies relevant for marine hydrodynamics. Sloshing in 3D rectangular tanks, a fully-nonlinear numerical wave tank, fully-nonlinear wave focusing on a semi-circular shoal, and the nonlinear wave diffraction of a bottom-mounted cylinder in regular waves are studied. The comparisons with the experimental results and other numerical results are all in satisfactory agreement, indicating that the present HPC method is a promising method in solving potential-flow problems. The underlying procedure of the HPC method could also be useful in other fields than marine hydrodynamics involved with solving Laplace equation.
Three-dimensional metamaterials
Burckel, David Bruce
2012-06-12
A fabrication method is capable of creating canonical metamaterial structures arrayed in a three-dimensional geometry. The method uses a membrane suspended over a cavity with predefined pattern as a directional evaporation mask. Metallic and/or dielectric material can be evaporated at high vacuum through the patterned membrane to deposit resonator structures on the interior walls of the cavity, thereby providing a unit cell of micron-scale dimension. The method can produce volumetric metamaterial structures comprising layers of such unit cells of resonator structures.
Three dimensional colorimetric assay assemblies
Charych, Deborah; Reichart, Anke
2000-01-01
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.
Electrode With Porous Three-Dimensional Support
Bernard, Patrick; Dauchier, Jean-Michel; Simonneau, Olivier
1999-07-27
Electrode including a paste containing particles of electrochemically active material and a conductive support consisting of a three-dimensional porous material comprising strands delimiting contiguous pores communicating via passages, characterized in that the average width L in .mu.m of said passages is related to the average diameter .O slashed. in .mu.m of said particles by the following equation, in which W and Y are dimensionless coefficients: wherein W=0.16 Y=1.69 X=202.4 .mu.m and Z=80 .mu.m
Three dimensional electromagnetic wavepackets in a plasma: Spatiotemporal modulational instability
Borhanian, J.; Hosseini Faradonbe, F.
2014-04-15
The nonlinear interaction of an intense electromagnetic beam with relativistic collisionless unmagnetized plasma is investigated by invoking the reductive perturbation technique, resting on the model of three-dimensional nonlinear Schrödinger (NLS) equation with cubic nonlinearity which incorporates the effects of self-focusing, self-phase modulation, and diffraction on wave propagation. Relying on the derived NLS equation, the occurrence of spatiotemporal modulational instability is investigated in detail.
Introduction to Control Theory. Part 2. Laplace Transforms and Linear Systems
Scheinker, Alexander
2015-09-11
Presentation for summer students. Start by considering linear differential equations, and how to solve them. The Laplace Transform is a great tool for solving linear differential equations.
Three-dimensional colorimetric assay assemblies
Charych, Deborah; Reichert, Anke
2001-01-01
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 piezoelectric vibration energy harvester using...
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Subject: 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; BEAMS; PEAKS; PIEZOELECTRICITY; SCAVENGING; SPACE; THREE-DIMENSIONAL CALCULATIONS; THREE-DIMENSIONAL ...
Noncommutative geometry for three-dimensional topological insulators...
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Noncommutative geometry for three-dimensional topological insulators Title: Noncommutative geometry for three-dimensional topological insulators Authors: Neupert, Titus ; Santos, ...
New classes of three-dimensional topological crystalline insulators...
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New classes of three-dimensional topological crystalline insulators: Nonsymmorphic and magnetic Citation Details In-Document Search Title: New classes of three-dimensional ...
Real time three dimensional sensing system
Gordon, Steven J.
1996-01-01
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.
Real time three dimensional sensing system
Gordon, S.J.
1996-12-31
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.
Three-dimensional display of document set
Lantrip, David B.; Pennock, Kelly A.; Pottier, Marc C.; Schur, Anne; Thomas, James J.; Wise, James A.
2006-09-26
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
2001-10-02
A method for spatializing text content for enhanced visual browsing and analysis. The invention is applied to large text document corpora such as digital libraries, regulations and procedures, archived reports, and the like. The text content from these sources may be transformed to a spatial representation that preserves informational characteristics from the documents. The three-dimensional representation may then be visually browsed and analyzed in ways that avoid language processing and that reduce the analysts' effort.
Three-dimensional display of document set
Lantrip, David B.; Pennock, Kelly A.; Pottier, Marc C.; Schur, Anne; Thomas, James J.; Wise, James A.; York, Jeremy
2009-06-30
A method for spatializing text content for enhanced visual browsing and analysis. The invention is applied to large text document corpora such as digital libraries, regulations and procedures, archived reports, and the like. The text content from these sources may be transformed to a spatial representation that preserves informational characteristics from the documents. The three-dimensional representation may then be visually browsed and analyzed in ways that avoid language processing and that reduce the analysts' effort.
Three-Dimensional Dispaly Of Document Set
Lantrip, David B.; Pennock, Kelly A.; Pottier, Marc C.; Schur, Anne; Thomas, James J.; Wise, James A.
2003-06-24
A method for spatializing text content for enhanced visual browsing and analysis. The invention is applied to large text document corpora such as digital libraries, regulations and procedures, archived reports, and the like. The text content from these sources may be transformed to a spatial representation that preserves informational characteristics from the documents. The three-dimensional representation may then be visually browsed and analyzed in ways that avoid language processing and that reduce the analysts' effort.
Three-dimensional modeling of the plasma arc in arc welding
Xu, G.; Tsai, H. L.; Hu, J.
2008-11-15
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.
High resolution three-dimensional doping profiler
Thundat, Thomas G. (Knoxville, TN); Warmack, Robert J. (Knoxville, TN)
1999-01-01
A semiconductor doping profiler provides a Schottky contact at one surface and an ohmic contact at the other. While the two contacts are coupled to a power source, thereby establishing an electrical bias in the semiconductor, a localized light source illuminates the semiconductor to induce a photocurrent. The photocurrent changes in accordance with the doping characteristics of the semiconductor in the illuminated region. By changing the voltage of the power source the depth of the depletion layer can be varied to provide a three dimensional view of the local properties of the semiconductor.
Two component-three dimensional catalysis
Schwartz, Michael; White, James H.; Sammells, Anthony F.
2002-01-01
This invention relates to catalytic reactor membranes having a gas-impermeable membrane for transport of oxygen anions. The membrane has an oxidation surface and a reduction surface. The membrane is coated on its oxidation surface with an adherent catalyst layer and is optionally coated on its reduction surface with a catalyst that promotes reduction of an oxygen-containing species (e.g., O.sub.2, NO.sub.2, SO.sub.2, etc.) to generate oxygen anions on the membrane. The reactor has an oxidation zone and a reduction zone separated by the membrane. A component of an oxygen containing gas in the reduction zone is reduced at the membrane and a reduced species in a reactant gas in the oxidation zone of the reactor is oxidized. The reactor optionally contains a three-dimensional catalyst in the oxidation zone. The adherent catalyst layer and the three-dimensional catalyst are selected to promote a desired oxidation reaction, particularly a partial oxidation of a hydrocarbon.
Three-dimensional elastic lidar winds
Buttler, W.T.
1996-07-01
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 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.
Propagation of three-dimensional electron-acoustic solitary waves
Shalaby, M.; El-Sherif, L. S.; El-Labany, S. K.; Sabry, R.
2011-06-15
Theoretical investigation is carried out for understanding the properties of three-dimensional electron-acoustic waves propagating in magnetized plasma whose constituents are cold magnetized electron fluid, hot electrons obeying nonthermal distribution, and stationary ions. For this purpose, the hydrodynamic equations for the cold magnetized electron fluid, nonthermal electron density distribution, and the Poisson equation are used to derive the corresponding nonlinear evolution equation, Zkharov-Kuznetsov (ZK) equation, in the small- but finite- amplitude regime. The ZK equation is solved analytically and it is found that it supports both solitary and blow-up solutions. It is found that rarefactive electron-acoustic solitary waves strongly depend on the density and temperature ratios of the hot-to-cold electron species as well as the nonthermal electron parameter. Furthermore, there is a critical value for the nonthermal electron parameter, which decides whether the electron-acoustic solitary wave's amplitude is decreased or increased by changing various plasma parameters. Importantly, the change of the propagation angles leads to miss the balance between the nonlinearity and dispersion; hence, the localized pulses convert to explosive/blow-up pulses. The relevance of this study to the nonlinear electron-acoustic structures in the dayside auroral zone in the light of Viking satellite observations is discussed.
Three-dimensional charge coupled device
Conder, Alan D.; Young, Bruce K. F.
1999-01-01
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.
Locally Advanced Prostate Cancer: Three-Dimensional Magnetic Resonance
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Spectroscopy to Monitor Prostate Response to Therapy (Journal Article) | SciTech Connect Locally Advanced Prostate Cancer: Three-Dimensional Magnetic Resonance Spectroscopy to Monitor Prostate Response to Therapy Citation Details In-Document Search Title: Locally Advanced Prostate Cancer: Three-Dimensional Magnetic Resonance Spectroscopy to Monitor Prostate Response to Therapy Purpose: To correlate results of three-dimensional magnetic resonance spectroscopic imaging (MRSI) with
Radiation hardness of three-dimensional polycrystalline diamond detectors
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(Journal Article) | SciTech Connect Radiation hardness of three-dimensional polycrystalline diamond detectors Citation Details In-Document Search Title: Radiation hardness of three-dimensional polycrystalline diamond detectors The three-dimensional concept in particle detection is based on the fabrication of columnar electrodes perpendicular to the surface of a solid state radiation sensor. It permits to improve the radiation resistance characteristics of a material by lowering the necessary
Charge Transport within a Three-Dimensional DNA Nanostructure Framework
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Charge Transport within a Three-Dimensional DNA Nanostructure Framework Authors: Lu, N., Pei, H., Ge, Z., Simmons, C.R., Yan, H., and Fan, C. Title: Charge Transport within a Three-Dimensional DNA Nanostructure Framework Source: Journal of the American Chemical Society Year: 2012 Volume: 134 Pages: 13148-13151 ABSTRACT: Three-dimensional (3D) DNA nanostructures have shown great promise for various applications including molecular sensing and therapeutics. Here we report kinetic studies of
Transient behavior of a supersonic three-dimensional micronozzle...
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Transient behavior of a supersonic three-dimensional micronozzle with an intersecting ... This content will become publicly available on February 16, 2017 Title: Transient behavior ...
Three-dimensional tokamak equilibria in the presence of resonant...
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Numerical solutions are described for three-dimensional MHD equilibria in the presence of resonant magnetic field perturbations. The effects of a realistic spectrum of resonant ...
Final Report - Three-dimensional minority carrier lifetime mapping...
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mapping of thin film semiconductors for solar cell applications Final Report - Three-dimensional minority carrier lifetime mapping of thin film semiconductors for solar cell ...
Three-Dimensional Thermal Tomography Advances Cancer Treatment...
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treatment. A recent advance in thermal imaging allows more rapid, yet still non-invasive, detection. The process, called three-dimensional thermal tomography, or 3DTT, is...
Wind Turbine Manufacturing Transforms with Three-Dimensional Printing
Broader source: Energy.gov [DOE]
From medical devices to airplane components, three-dimensional (3-D) printing (also called additive manufacturing) is transforming the manufacturing industry. Now, research that supports the Energy...
Locally Advanced Prostate Cancer: Three-Dimensional Magnetic...
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Cancer: Three-Dimensional Magnetic Resonance Spectroscopy to Monitor Prostate Response to Therapy Citation Details In-Document Search Title: Locally Advanced Prostate Cancer: ...
Three-dimensional Modeling of Fracture Clusters in Geothermal...
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of Fracture Clusters in Geothermal Reservoirs; 2010 Geothermal Technology Program Peer Review Report Three-dimensional Modeling of Fracture Clusters in Geothermal Reservoirs;...
The impact of disorder on charge transport in three dimensional...
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Title: The impact of disorder on charge transport in three dimensional quantum dot resonant tunneling structures Efficient iso-entropic energy filtering of electronic waves can be ...
Three-Dimensional Composite Nanostructures for Lean NOx Emission...
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More Documents & Publications Three-Dimensional Composite Nanostructures for Lean NOx Emission Control Monolithic Metal Oxide based Composite Nanowire Lean NOx Emission...
Three-Dimensional Modeling and Simulation of DNA Hybridization...
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Three-Dimensional Modeling and Simulation of DNA Hybridization Kinetics and Mass Transport ... Kinetics and Mass Transport as Functions of Temperature in a Microfluidic Channel. ...
Three-Dimensional Composite Nanostructures for Lean NOx Emission...
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Monolithic Metal Oxide based Composite Nanowire Lean NOx Emission Control Catalysts Three-Dimensional Composite Nanostructures for Lean NOx Emission Control Vehicle Technologies ...
Three-Dimensional Thermal Tomography Advances Cancer Treatment...
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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 Modeling of Fracture Clusters in Geeothermal Reservoirs
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Three-dimensional Modeling of Fracture Clusters in Geeothermal Reservoirs presentation at the April 2013 peer review meeting held in Denver, Colorado.
Integrated Three-Dimensional Module Heat Exchange for Power Electronic...
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Return to Search Integrated Three-Dimensional Module Heat Exchange for Power Electronics ... while at the same time enabling heat removal from the semiconductor devices ...
DNA Origami with Complex Curvatures in Three-Dimensional Space
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DNA Origami with Complex Curvatures in Three-Dimensional Space Authors: Han, D., Pal, S., Nangreave, J., Deng, Z., Liu, Y., and Yan, H. Title: DNA Origami with Complex Curvatures in Three-Dimensional Space Source: Science Year: 2011 Volume: 332 Pages: 342-346 ABSTRACT: We present a strategy to design and construct self-assembling DNA nanostructures that define intricate curved surfaces in three-dimensional (3D) space using the DNA origami folding technique. Double-helical DNA is bent to follow
The Three-Dimensional Structural Basis of Type II Hyperprolinemia...
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Journal Article: The Three-Dimensional Structural Basis of Type II Hyperprolinemia Citation Details In-Document Search ... Here, we report the first structure of human P5CDH (HsP5CDH) ...
Three-Dimensional Lithium-Ion Battery Model (Presentation)
Kim, G. H.; Smith, K.
2008-05-01
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.
Three-dimensional Dendritic Needle Network model with application...
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We present a three-dimensional (3D) extension of a previously proposed multi-scale ... of a given thickness, one can directly extend the DNN approach to 3D modeling. ...
Hierarchical Three-Dimensional Microbattery Electrodes Combining Bottom-Up
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Self-Assembly and Top-Down Micromachining (Journal Article) | SciTech Connect Hierarchical Three-Dimensional Microbattery Electrodes Combining Bottom-Up Self-Assembly and Top-Down Micromachining Citation Details In-Document Search Title: Hierarchical Three-Dimensional Microbattery Electrodes Combining Bottom-Up Self-Assembly and Top-Down Micromachining Authors: Gerasopoulos, K ; Pomerantseva, Ekaterina ; McCarthy, M ; Brown, A ; Wang, Chunsheng ; Culver, J N ; Ghodssi, Reza Publication Date:
Highly Ordered Tailored Three-Dimensional Hierarchical Porous Gold
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Architectures. (Journal Article) | SciTech Connect Journal Article: Highly Ordered Tailored Three-Dimensional Hierarchical Porous Gold Architectures. Citation Details In-Document Search Title: Highly Ordered Tailored Three-Dimensional Hierarchical Porous Gold Architectures. Abstract not provided. Authors: Polsky, Ronen ; Brozik, Susan Marie ; Washburn, Cody M. ; Wheeler, David Roger ; Burckel, David Bruce ; sattayasamtsathit, sirilak ; OMahony, Aoife ; Gao, Wei ; Minteer, Shelley ; Cha,
New classes of three-dimensional topological crystalline insulators:
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Nonsymmorphic and magnetic (Journal Article) | SciTech Connect New classes of three-dimensional topological crystalline insulators: Nonsymmorphic and magnetic Citation Details In-Document Search Title: New classes of three-dimensional topological crystalline insulators: Nonsymmorphic and magnetic Authors: Fang, Chen ; Fu, Liang Publication Date: 2015-04-15 OSTI Identifier: 1179956 Grant/Contract Number: SC0010526 Type: Publisher's Accepted Manuscript Journal Name: Physical Review B
Three Dimensional Simulation of the Baneberry Nuclear Event (Conference) |
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SciTech Connect Three Dimensional Simulation of the Baneberry Nuclear Event Citation Details In-Document Search Title: Three Dimensional Simulation of the Baneberry Nuclear Event 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
Three dimensional stress vector sensor array and method therefor (Patent) |
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SciTech Connect Three dimensional stress vector sensor array and method therefor Citation Details In-Document Search Title: Three dimensional stress vector sensor array and method therefor A sensor array is configured based upon capacitive sensor techniques to measure stresses at various positions in a sheet simultaneously and allow a stress map to be obtained in near real-time. The device consists of single capacitive elements applied in a one or two dimensional array to measure the
Three-Dimensional Crystallization of Vortex Strings in Frustrated Quantum
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Magnets (Journal Article) | SciTech Connect Three-Dimensional Crystallization of Vortex Strings in Frustrated Quantum Magnets Citation Details In-Document Search This content will become publicly available on August 31, 2016 Title: Three-Dimensional Crystallization of Vortex Strings in Frustrated Quantum Magnets Authors: Wang, Zhentao ; Kamiya, Yoshitomo ; Nevidomskyy, Andriy H. ; Batista, Cristian D. Publication Date: 2015-09-01 OSTI Identifier: 1213756 Grant/Contract Number: AC52-06NA25396
Three-dimensional piezoelectric vibration energy harvester using
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spiral-shaped beam with triple operating frequencies (Journal Article) | SciTech Connect Three-dimensional piezoelectric vibration energy harvester using spiral-shaped beam with triple operating frequencies Citation Details In-Document Search Title: Three-dimensional piezoelectric vibration energy harvester using spiral-shaped beam with triple operating frequencies This work has demonstrated a novel piezoelectric energy harvester without a complex structure and appended component that is
Ray tracing a three dimensional scene using a grid
Wald, Ingo; Ize, Santiago; Parker, Steven G; Knoll, Aaron
2013-02-26
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.
Radiation hardness of three-dimensional polycrystalline diamond detectors
Lagomarsino, Stefano Sciortino, Silvio; Bellini, Marco; Corsi, Chiara; Cindro, Vladimir; Kanxheri, Keida; Servoli, Leonello; Morozzi, Arianna; Passeri, Daniele; Schmidt, Christian J.
2015-05-11
The three-dimensional concept in particle detection is based on the fabrication of columnar electrodes perpendicular to the surface of a solid state radiation sensor. It permits to improve the radiation resistance characteristics of a material by lowering the necessary bias voltage and shortening the charge carrier path inside the material. If applied to a long-recognized exceptionally radiation-hard material like diamond, this concept promises to pave the way to the realization of detectors of unprecedented performances. We fabricated conventional and three-dimensional polycrystalline diamond detectors, and tested them before and after neutron damage up to 1.2 Ă—10{sup 16â€‰}cm{sup â’2}, 1â€‰MeV-equivalent neutron fluence. We found that the signal collected by the three-dimensional detectors is up to three times higher than that of the conventional planar ones, at the highest neutron damage ever experimented.
Coupled particle dispersion by three-dimensional vortex structures
Troutt, T.R.; Chung, J.N.; Crowe, C.T.
1996-12-31
The primary objective of this research program is to obtain understanding concerning the role of three-dimensional vortex structures in the dispersion of particles and droplets in free shear flows. This research program builds on previous studies which focused on the nature of particle dispersion in large scale quasi two-dimensional vortex structures. This investigation employs time dependent experimental and numerical techniques to provide information concerning the particulate dispersion produced by three dimensional vortex structures in free shear layers. The free shear flows investigated include modified plane mixing layers, and modified plane wakes. The modifications to these flows involve slight perturbations to the initiation boundary conditions such that three-dimensional vortex structures are rapidly generated by the experimental and numerical flow fields. Recent results support the importance of these vortex structures in the particle dispersion process.
Novel multipole Wien filter as three-dimensional spin manipulator
Yasue, T. Suzuki, M.; Koshikawa, T.; Tsuno, K.; Goto, S.; Arai, Y.
2014-04-15
Spin polarized electron beam is often used in material characterizations which relates to magnetism as well as in the high energy particle physics. The manipulation of the spin polarization toward the arbitrary direction is indispensable in such studies. In the present work, a novel multipole Wien filter is proposed as the three-dimensional spin manipulator, and a prototype 8-pole Wien filter is developed. It is applied to spin polarized low energy electron microscopy, and the variation of the magnetic contrast with managing the spin polarization is evaluated. It is confirmed that the novel multipole Wien filter can manipulate the spin polarization three-dimensionally.
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
2014-09-09
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.
Three-Dimensional Thermal Tomography Advances Cancer Treatment | Argonne
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
National Laboratory 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 cancer patients. Lowers medical costs due to lessened side effects Noninvasive, enhances healing and detects other conditions PDF icon thermal_tomography
Alaska Maximum Number of Active Crews Engaged in Three-Dimensional...
Gasoline and Diesel Fuel Update (EIA)
Three-Dimensional Seismic Surveying (Number of Elements) Alaska Maximum Number of Active Crews Engaged in Three-Dimensional Seismic Surveying (Number of Elements) Year Jan Feb Mar...
DYNA3D: A nonlinear, explicit, three-dimensional finite element...
Office of Scientific and Technical Information (OSTI)
three-dimensional finite element code for solid and structural mechanics, User manual. ... three-dimensional finite element code for solid and structural mechanics, User manual. ...
Theory and application of a three-dimensional code SHAPS to complex piping systems. [LMFBR
Wang, C.Y.
1983-01-01
This paper describes the theory and application of a three-dimensional computer code SHAPS to the complex piping systems. The code utilizes a two-dimensional implicit Eulerian method for the hydrodynamic analysis together with a three-dimensional elastic-plastic finite-element program for the structural calculation. A three-dimensional pipe element with eight degrees of freedom is employed to account for the hoop, flexural, axial, and the torsional mode of the piping system. In the SHAPS analysis the hydrodynamic equations are modified to include the global piping motion. Coupling between fluid and structure is achieved by enforcing the free-slip boundary conditions. Also, the response of the piping network generated by the seismic excitation can be included. A thermal transient capability is also provided in SHAPS. To illustrate the methodology, many sample problems dealing with the hydrodynamic, structural, and thermal analyses of reactor-piping systems are given. Validation of the SHAPS code with experimental data is also presented.
Three Dimensional Thermal Abuse Reaction Model for Lithium Ion Batteries
Energy Science and Technology Software Center (OSTI)
2006-06-29
Three dimensional computer models for simulating thermal runaway of lithium ion battery was developed. The three-dimensional model captures the shapes and dimensions of cell components and the spatial distributions of materials and temperatures, so we could consider the geometrical features, which are critical especially in large cells. An array of possible exothermic reactions, such as solid-electrolyte-interface (SEI) layer decomposition, negative active/electrolyte reaction, and positive active/electrolyte reaction, were considered and formulated to fit experimental data frommoreÂ Â» accelerating rate calorimetry and differential scanning calorimetry. User subroutine code was written to implement NREL developed approach and to utilize a commercially available solver. The model is proposed to use for simulation a variety of lithium-ion battery safety events including thermal heating and short circuit.Â«Â less
Three-dimensional discrete ordinates reactor assembly calculations on GPUs
Evans, Thomas M; Joubert, Wayne; Hamilton, Steven P; Johnson, Seth R; Turner, John A; Davidson, Gregory G; Pandya, Tara M
2015-01-01
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.
Environmental, Transient, Three-Dimensional, Hydrothermal, Mass Transport Code - FLESCOT
Onishi, Yasuo; Bao, Jie; Glass, Kevin A.; Eyler, L. L.; Okumura, Masahiko
2015-03-28
The purpose of the project was to modify and apply the transient, three-dimensional FLESCOT code to be able to effectively simulate cesium behavior in Fukushima lakes/dam reservoirs, river mouths, and coastal areas. The ultimate objective of the FLESCOT simulation is to predict future changes of cesium accumulation in Fukushima area reservoirs and costal water. These evaluation results will assist ongoing and future environmental remediation activities and policies in a systematic and comprehensive manner.
Unprecedented Precise Determination of Three-Dimensional Atomic Positions |
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
U.S. DOE Office of Science (SC) Unprecedented Precise Determination of Three-Dimensional Atomic Positions Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy Sciences Advisory Committee (BESAC) Community Resources Contact Information Basic Energy Sciences U.S. Department of Energy SC-22/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3081 F: (301) 903-6594 E: Email Us More
Explicit expressions for three-dimensional boundary integrals in linear elasticity
Nintcheu Fata, Sylvain
2011-01-01
On employing isoparametric, piecewise linear shape functions over a flat triangle, exact formulae are derived for all surface potentials involved in the numerical treatment of three-dimensional singular and hyper-singular boundary integral equations in linear elasticity. These formulae are valid for an arbitrary source point in space and are represented as analytical expressions along the edges of the integration triangle. They can be employed to solve integral equations defined on triangulated surfaces via a collocation method or may be utilized as analytical expressions for the inner integrals in a Galerkin technique. A numerical example involving a unit triangle and a source point located at various distances above it, as well as sample problems solved by a collocation boundary element method for the Lame equation are included to validate the proposed formulae.
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)
2008-06-17
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.
Methods for preparation of three-dimensional bodies
Mulligan, Anthony C.; Rigali, Mark J.; Sutaria, Manish P.; Artz, Gregory J.; Gafner, Felix H.; Vaidyanathan, K. Ranji
2004-09-28
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 amorphous silicon/microcrystalline silicon solar cells
Kaschmitter, James L.
1996-01-01
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.
Three dimensional amorphous silicon/microcrystalline silicon solar cells
Kaschmitter, J.L.
1996-07-23
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 separation trap based on dielectrophoresis and use thereof
Mariella, Jr., Raymond P.
2004-05-04
An apparatus is adapted to separate target materials from other materials in a flow containing the target materials and other materials. A dielectrophoretic trap is adapted to receive the target materials and the other materials. At least one electrode system is provided in the trap. The electrode system has a three-dimensional configuration. The electrode system includes a first electrode and a second electrode that are shaped and positioned relative to each such that application of an electrical voltage to the first electrode and the second electrode creates a dielectrophoretic force and said dielectrophoretic force does not reach zero between the first electrode and the second electrode.
Usmanov, Arcadi V.; Matthaeus, William H.; Goldstein, Melvyn L.
2014-06-10
We have developed a three-fluid, three-dimensional magnetohydrodynamic solar wind model that incorporates turbulence transport, eddy viscosity, turbulent resistivity, and turbulent heating. The solar wind plasma is described as a system of co-moving solar wind protons, electrons, and interstellar pickup protons, with separate energy equations for each species. Numerical steady-state solutions of Reynolds-averaged solar wind equations coupled with turbulence transport equations for turbulence energy, cross helicity, and correlation length are obtained by the time relaxation method in the corotating with the Sun frame of reference in the region from 0.3 to 100 AU (but still inside the termination shock). The model equations include the effects of electron heat conduction, Coulomb collisions, photoionization of interstellar hydrogen atoms and their charge exchange with the solar wind protons, turbulence energy generation by pickup protons, and turbulent heating of solar wind protons and electrons. The turbulence transport model is based on the Reynolds decomposition and turbulence phenomenologies that describe the conversion of fluctuation energy into heat due to a turbulent cascade. In addition to using separate energy equations for the solar wind protons and electrons, a significant improvement over our previous work is that the turbulence model now uses an eddy viscosity approximation for the Reynolds stress tensor and the mean turbulent electric field. The approximation allows the turbulence model to account for driving of turbulence by large-scale velocity gradients. Using either a dipole approximation for the solar magnetic field or synoptic solar magnetograms from the Wilcox Solar Observatory for assigning boundary conditions at the coronal base, we apply the model to study the global structure of the solar wind and its three-dimensional properties, including embedded turbulence, heating, and acceleration throughout the heliosphere. The model results are compared with plasma and magnetic field observations on WIND, Ulysses, and Voyager 2 spacecraft.
Energy Science and Technology Software Center (OSTI)
2008-10-05
Laplace is a electric field driven flow simulation program for detailed device design support. Transport processes include electrokinesis, dielectrophoresis, and diffusion. Laplace solves for the electric field in a microfluidic system and the liquid and particle flow that is produced by the electric field for the primary purpose of microfluidic design development and simulation. Laplace allows you to visualize the flow by tracking tracer particles, viewing flow streamlines, etc. Laplace can make movies of simulatedmoreÂ Â» particle motion to allow you to test and share the behavior of microfuidic designs. The electric field is calculated using an iterative linear solver and particle motion is solved by finite difference, finite-displacement simulation of particle trajectories. Laplace uses a bitmapped picture or drawing of a microsystem to infer the geometry. The channel depth is everywhere proportional to the magnitude of the blue channel of the image: 0 (black) = zero depth, or no channel, 256 (saturated blue) = deepest channel, and intermediate values correspond to intermediate depths. Laplace automatically applies various boundary conditions (applied voltage or current) to ports, where channels cross the edge of the image.Â«Â less
Tracker: A three-dimensional raytracing program for ionospheric radio propagation
Argo, P.E.; DeLapp, D.; Sutherland, C.D.; Farrer, R.G.
1994-12-01
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.
Epitaxial growth of three-dimensionally architectured optoelectronic devices
Nelson, Erik C.; Dias, Neville L.; Bassett, Kevin P.; Dunham, Simon N.; Verma, Varun; Miyake, Masao; Wiltzius, Pierre; Rogers, John A.; Coleman, James J.; Li, Xiuling; Braun, Paul V.
2011-07-24
Optoelectronic devices have long benefited from structuring in multiple dimensions on microscopic length scales. However, preserving crystal epitaxy, a general necessity for good optoelectronic properties, while imparting a complex three-dimensional structure remains a significant challenge. Three-dimensional (3D) photonic crystals are one class of materials where epitaxy of 3D structures would enable new functionalities. Many 3D photonic crystal devices have been proposed, including zero-threshold lasers, low-loss waveguides, high-efficiency light-emitting diodes (LEDs) and solar cells, but have generally not been realized because of material limitations. Exciting concepts in metamaterials, including negative refraction and cloaking, could be made practical using 3D structures that incorporate electrically pumped gain elements to balance the inherent optical loss of such devices. Here we demonstrate the 3D-template-directed epitaxy of group III–V materials, which enables formation of 3D structured optoelectronic devices. We illustrate the power of this technique by fabricating an electrically driven 3D photonic crystal LED.
Three-dimensional light trap for reflective particles
Neal, Daniel R.
1999-01-01
A system for containing either a reflective particle or a particle having an index of refraction lower than that of the surrounding media in a three-dimensional light cage. A light beam from a single source illuminates an optics system and generates a set of at least three discrete focussed beams that emanate from a single exit aperture and focus on to a focal plane located close to the particle. The set of focal spots defines a ring that surrounds the particle. The set of focussed beams creates a "light cage" and circumscribes a zone of no light within which the particle lies. The surrounding beams apply constraining forces (created by radiation pressure) to the particle, thereby containing it in a three-dimensional force field trap. A diffractive element, such as an aperture multiplexed lens, or either a Dammann grating or phase element in combination with a focusing lens, may be used to generate the beams. A zoom lens may be used to adjust the size of the light cage, permitting particles of various sizes to be captured and contained.
Three-dimensional light trap for reflective particles
Neal, D.R.
1999-08-17
A system is disclosed for containing either a reflective particle or a particle having an index of refraction lower than that of the surrounding media in a three-dimensional light cage. A light beam from a single source illuminates an optics system and generates a set of at least three discrete focused beams that emanate from a single exit aperture and focus on to a focal plane located close to the particle. The set of focal spots defines a ring that surrounds the particle. The set of focused beams creates a ``light cage`` and circumscribes a zone of no light within which the particle lies. The surrounding beams apply constraining forces (created by radiation pressure) to the particle, thereby containing it in a three-dimensional force field trap. A diffractive element, such as an aperture multiplexed lens, or either a Dammann grating or phase element in combination with a focusing lens, may be used to generate the beams. A zoom lens may be used to adjust the size of the light cage, permitting particles of various sizes to be captured and contained. 10 figs.
Three-dimensional photodissociation in strong laser fields: Memory-kernel effective-mode expansion
Li Xuan; Thanopulos, Ioannis; Shapiro, Moshe
2011-03-15
We introduce a method for the efficient computation of non-Markovian quantum dynamics for strong (and time-dependent) system-bath interactions. The past history of the system dynamics is incorporated by expanding the memory kernel in exponential functions thereby transforming in an exact fashion the non-Markovian integrodifferential equations into a (larger) set of ''effective modes'' differential equations (EMDE). We have devised a method which easily diagonalizes the EMDE, thereby allowing for the efficient construction of an adiabatic basis and the fast propagation of the EMDE in time. We have applied this method to three-dimensional photodissociation of the H{sub 2}{sup +} molecule by strong laser fields. Our calculations properly include resonance-Raman scattering via the continuum, resulting in extensive rotational and vibrational excitations. The calculated final kinetic and angular distribution of the photofragments are in overall excellent agreement with experiments, both when transform-limited pulses and when chirped pulses are used.
Three dimensional simulation for bayou choctaw strategic petroleum reserve (SPR).
Ehgartner, Brian L. (Sandia National Laboratories, Albuquerque, NM); Park, Byoung Yoon; Lee, Moo Yul
2006-12-01
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.
Life-cycle environmental analysis--A three dimensional view
Sutherlin, K.L.; Black, R.E. )
1993-01-01
Both the US Air Force and the US Army have recently increased their emphasis on life-cycles of weapons systems. Along with that emphasis, there has also been an increase in emphasis in life-cycle National Environmental Policy Act (NEPA) documentation. Conflicts and inefficiencies arise when a weapon system is fielded and prompts the need for a site-specific environmental analysis. In their research and experience, the authors found no real link between life-cycle environmental analysis and site-specific environmental analyses required at various points within the life-cycle of a weapon. This other look at the relation between life-cycle and site-specific environmental analyses has the potential to increase efficiency in NEPA compliance actions and save tax dollars in the process. The authors present a three-dimensional model that relates life-cycle analyses to site-specific analyses.
Three dimensional imaging detector employing wavelength-shifting optical fibers
Worstell, William A.
1997-01-01
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 periodic dielectric structures having photonic Dirac points
Bravo-Abad, Jorge; Joannopoulos, John D.; Soljacic, Marin
2015-06-02
The dielectric, three-dimensional photonic materials disclosed herein feature Dirac-like dispersion in quasi-two-dimensional systems. Embodiments include a face-centered cubic (fcc) structure formed by alternating layers of dielectric rods and dielectric slabs patterned with holes on respective triangular lattices. This fcc structure also includes a defect layer, which may comprise either dielectric rods or a dielectric slab with patterned with holes. This defect layer introduces Dirac cone dispersion into the fcc structure's photonic band structure. Examples of these fcc structures enable enhancement of the spontaneous emission coupling efficiency (the .beta.-factor) over large areas, contrary to the conventional wisdom that the .beta.-factor degrades as the system's size increases. These results enable large-area, low-threshold lasers; single-photon sources; quantum information processing devices; and energy harvesting systems.
The three-dimensional morphology of growing dendrites
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Gibbs, J. W.; Mohan, K. A.; Gulsoy, E. B.; Shahani, A. J.; Xiao, X.; Bouman, C. A.; De Graef, M.; Voorhees, P. W.
2015-07-03
The processes controlling the morphology of dendrites have been of great interest to a wide range of communities, since they are examples of an out-of-equilibrium pattern forming system, there is a clear connection with battery failure processes, and their morphology sets the properties of many metallic alloys. We determine the three-dimensional morphology of free growing metallic dendrites using a novel X-ray tomographic technique that improves the temporal resolution by more than an order of magnitude compared to conventional techniques. These measurements show that the growth morphology of metallic dendrites is surprisingly different from that seen in model systems, the morphologymoreÂ Â» is not self-similar with distance back from the tip, and that this morphology can have an unexpectedly strong influence on solute segregation in castings. These experiments also provide benchmark data that can be used to validate simulations of free dendritic growth.Â«Â less
Three dimensional imaging detector employing wavelength-shifting optical fibers
Worstell, W.A.
1997-02-04
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.
The three-dimensional morphology of growing dendrites
Gibbs, J. W.; Mohan, K. A.; Gulsoy, E. B.; Shahani, A. J.; Xiao, X.; Bouman, C. A.; De Graef, M.; Voorhees, P. W.
2015-07-03
The processes controlling the morphology of dendrites have been of great interest to a wide range of communities, since they are examples of an out-of-equilibrium pattern forming system, there is a clear connection with battery failure processes, and their morphology sets the properties of many metallic alloys. We determine the three-dimensional morphology of free growing metallic dendrites using a novel X-ray tomographic technique that improves the temporal resolution by more than an order of magnitude compared to conventional techniques. These measurements show that the growth morphology of metallic dendrites is surprisingly different from that seen in model systems, the morphology is not self-similar with distance back from the tip, and that this morphology can have an unexpectedly strong influence on solute segregation in castings. These experiments also provide benchmark data that can be used to validate simulations of free dendritic growth.
Structures with three dimensional nanofences comprising single crystal segments
Goyal, Amit; Wee, Sung-Hun
2013-08-27
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.
Three-dimensional infrared metamaterial with asymmetric transmission
Kenanakis, George; Xomalis, Aggelos; Selimis, Alexandros; Vamvakaki, Maria; Farsari, Maria; Kafesaki, Maria; Soukoulis, Costas M.; Economou, Eleftherios N.
2015-01-14
A novel three-dimensional (3D) metallic metamaterial structure with asymmetric transmission for linear polarization is demonstrated in the infrared spectral region. The structure was fabricated by direct laser writing and selective electroless silver coating, a straightforward, novel technique producing mechanically and chemically stable 3D photonic structures. The structure unit cell is composed of a pair of conductively coupled magnetic resonators, and the asymmetric transmission response results from interplay of electric and magnetic responses; this equips the structure with almost total opaqueness along one propagation direction versus satisfying transparency along the opposite one. It also offers easily adjustable impedance, 90Â° one-way pure optical activity and backward propagation possibility, resulting thus in unique capabilities in polarization control and isolation applications. We show also that scaling down the structure can make it capable of exhibiting its asymmetric transmission and its polarization capabilities in the optical region.
Three-dimensional infrared metamaterial with asymmetric transmission
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Kenanakis, George; Xomalis, Aggelos; Selimis, Alexandros; Vamvakaki, Maria; Farsari, Maria; Kafesaki, Maria; Soukoulis, Costas M.; Economou, Eleftherios N.
2015-01-14
A novel three-dimensional (3D) metallic metamaterial structure with asymmetric transmission for linear polarization is demonstrated in the infrared spectral region. The structure was fabricated by direct laser writing and selective electroless silver coating, a straightforward, novel technique producing mechanically and chemically stable 3D photonic structures. The structure unit cell is composed of a pair of conductively coupled magnetic resonators, and the asymmetric transmission response results from interplay of electric and magnetic responses; this equips the structure with almost total opaqueness along one propagation direction versus satisfying transparency along the opposite one. It also offers easily adjustable impedance, 90Â° one-way puremoreÂ Â» optical activity and backward propagation possibility, resulting thus in unique capabilities in polarization control and isolation applications. We show also that scaling down the structure can make it capable of exhibiting its asymmetric transmission and its polarization capabilities in the optical region.Â«Â less
Three dimensional numerical simulations of the UPS-292-SC engine
O'Rourke, P.J.; Amsden, A.A.
1987-01-01
We present and analyze three-dimensional calculations of the spray, mixing and combustion in the UPS-292 stratified charge engine for three different operating conditions, corresponding to overall air-fuel ratios between 22.4 and 61.0. The numerical calculations are performed with KIVA, a multidimensional arbitrary-mesh, finite-difference hydrodynamics program for internal combustion engine applications. The calculations use a mesh of 10,000 computational cells, which conform to the shape of the piston bowl and cylinder and move to follow piston motion. Each operating condition is calculated from intake valve closure at 118/sup 0/ BTDC to 90/sup 0/ ATDC and requires approximately three hours of CRAY-XMP computer time.
THREE-DIMENSIONAL MORPHOLOGY OF A CORONAL PROMINENCE CAVITY
Gibson, S. E.; De Toma, G.; Rachmeler, L.; Rastawicki, D.; Dove, J.; Hao, J.; Zhang, M.; Hill, S.; Marque, C.; Seaton, D. B.; McIntosh, P. S.; Reeves, K. K.; Schmieder, B.; Schmit, D. J.; Sterling, A. C.; Williams, D. R.
2010-12-01
We present a three-dimensional density model of coronal prominence cavities, and a morphological fit that has been tightly constrained by a uniquely well-observed cavity. Observations were obtained as part of an International Heliophysical Year campaign by instruments from a variety of space- and ground-based observatories, spanning wavelengths from radio to soft X-ray to integrated white light. From these data it is clear that the prominence cavity is the limb manifestation of a longitudinally extended polar-crown filament channel, and that the cavity is a region of low density relative to the surrounding corona. As a first step toward quantifying density and temperature from campaign spectroscopic data, we establish the three-dimensional morphology of the cavity. This is critical for taking line-of-sight projection effects into account, since cavities are not localized in the plane of the sky and the corona is optically thin. We have augmented a global coronal streamer model to include a tunnel-like cavity with elliptical cross-section and a Gaussian variation of height along the tunnel length. We have developed a semi-automated routine that fits ellipses to cross-sections of the cavity as it rotates past the solar limb, and have applied it to Extreme Ultraviolet Imager observations from the two Solar Terrestrial Relations Observatory spacecraft. This defines the morphological parameters of our model, from which we reproduce forward-modeled cavity observables. We find that cavity morphology and orientation, in combination with the viewpoints of the observing spacecraft, explain the observed variation in cavity visibility for the east versus west limbs.
THE THREE-DIMENSIONAL ARCHITECTURE OF THE ? ANDROMEDAE PLANETARY SYSTEM
Deitrick, Russell; Barnes, Rory; Quinn, Thomas R.; Luger, Rodrigo; Antonsen, Adrienne [Department of Astronomy, University of Washington, Seattle, WA 98195-1580 (United States); McArthur, Barbara; Fritz Benedict, G., E-mail: deitrr@astro.washington.edu [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States)
2015-01-01
The ? Andromedae system is the first exoplanetary system to have the relative inclination of two planets' orbital planes directly measured, and therefore offers our first window into the three-dimensional configurations of planetary systems. We present, for the first time, full three-dimensional, dynamically stable configurations for the three planets of the system consistent with all observational constraints. While the outer two planets, c and d, are inclined by ?30°, the inner planet's orbital plane has not been detected. We use N-body simulations to search for stable three-planet configurations that are consistent with the combined radial velocity and astrometric solution. We find that only 10 trials out of 1000 are robustly stable on 100 Myr timescales, or ?8 billion orbits of planet b. Planet b's orbit must lie near the invariable plane of planets c and d, but can be either prograde or retrograde. These solutions predict that b's mass is in the range of 2-9 M {sub Jup} and has an inclination angle from the sky plane of less than 25°. Combined with brightness variations in the combined star/planet light curve ({sup p}hase curve{sup )}, our results imply that planet b's radius is ?1.8 R {sub Jup}, relatively large for a planet of its age. However, the eccentricity of b in several of our stable solutions reaches >0.1, generating upward of 10{sup 19} W in the interior of the planet via tidal dissipation, possibly inflating the radius to an amount consistent with phase curve observations.
Molecular-scale, Three-dimensional Non-Platinum Group Metal Electrodes...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Molecular-scale, Three-dimensional Non-Platinum Group Metal Electrodes for Catalysis of Fuel Cell Reactions Molecular-scale, Three-dimensional Non-Platinum Group Metal Electrodes...
A Three-Dimensional Carbon Nano-Network for High Performance...
Office of Scientific and Technical Information (OSTI)
A Three-Dimensional Carbon Nano-Network for High Performance Lithium Ion Batteries. Citation Details In-Document Search Title: A Three-Dimensional Carbon Nano-Network for High...
Three-Dimensional Modeling of the Reactive Transport of CO2 and...
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Three-Dimensional Modeling of the Reactive Transport of CO2 and Its Impact on ... Title: Three-Dimensional Modeling of the Reactive Transport of CO2 and Its Impact on ...
Oscillatory cellular patterns in three-dimensional directional solidification
Tourret, D.; Debierre, J. -M.; Song, Y.; Mota, F. L.; Bergeon, N.; Guerin, R.; Trivedi, R.; Billia, B.; Karma, A.
2015-09-11
We present a phase-field study of oscillatory breathing modes observed during the solidification of three-dimensional cellular arrays in micro-gravity. Directional solidification experiments conducted onboard the International Space Station have allowed for the first time to observe spatially extended homogeneous arrays of cells and dendrites while minimizing the amount of gravity-induced convection in the liquid. In situ observations of transparent alloys have revealed the existence, over a narrow range of control parameters, of oscillations in cellular arrays with a period ranging from about 25 to 125 minutes. Cellular patterns are spatially disordered, and the oscillations of individual cells are spatiotemporally uncorrelated at long distance. However, in regions displaying short-range spatial ordering, groups of cells can synchronize into oscillatory breathing modes. Quantitative phase-field simulations show that the oscillatory behavior of cells in this regime is linked to a stability limit of the spacing in hexagonal cellular array structures. For relatively high cellular front undercooling (\\ie low growth velocity or high thermal gradient), a gap appears in the otherwise continuous range of stable array spacings. Close to this gap, a sustained oscillatory regime appears with a period that compares quantitatively well with experiment. For control parameters where this gap exist, oscillations typically occur for spacings at the edge of the gap. However, after a change of growth conditions, oscillations can also occur for nearby values of control parameters where this gap just closes and a continuous range of spacings exists. In addition, sustained oscillations at to the opening of this stable gap exhibit a slow periodic modulation of the phase-shift among cells with a slower period of several hours. While long-range coherence of breathing modes can be achieved in simulations for a perfect spatial arrangement of cells as initial condition, global disorder is observed in both three-dimensional experiments and simulations from realistic noisy initial conditions. The, erratic tip splitting events promoted by large amplitude oscillations contribute to maintaining the long-range array disorder, unlike in thin sample experiments where long-range coherence of oscillations is experimentally observable.
Oscillatory cellular patterns in three-dimensional directional solidification
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Tourret, D.; Debierre, J. -M.; Song, Y.; Mota, F. L.; Bergeon, N.; Guerin, R.; Trivedi, R.; Billia, B.; Karma, A.
2015-09-11
We present a phase-field study of oscillatory breathing modes observed during the solidification of three-dimensional cellular arrays in micro-gravity. Directional solidification experiments conducted onboard the International Space Station have allowed for the first time to observe spatially extended homogeneous arrays of cells and dendrites while minimizing the amount of gravity-induced convection in the liquid. In situ observations of transparent alloys have revealed the existence, over a narrow range of control parameters, of oscillations in cellular arrays with a period ranging from about 25 to 125 minutes. Cellular patterns are spatially disordered, and the oscillations of individual cells are spatiotemporally uncorrelatedmoreÂ Â» at long distance. However, in regions displaying short-range spatial ordering, groups of cells can synchronize into oscillatory breathing modes. Quantitative phase-field simulations show that the oscillatory behavior of cells in this regime is linked to a stability limit of the spacing in hexagonal cellular array structures. For relatively high cellular front undercooling (\\ie low growth velocity or high thermal gradient), a gap appears in the otherwise continuous range of stable array spacings. Close to this gap, a sustained oscillatory regime appears with a period that compares quantitatively well with experiment. For control parameters where this gap exist, oscillations typically occur for spacings at the edge of the gap. However, after a change of growth conditions, oscillations can also occur for nearby values of control parameters where this gap just closes and a continuous range of spacings exists. In addition, sustained oscillations at to the opening of this stable gap exhibit a slow periodic modulation of the phase-shift among cells with a slower period of several hours. While long-range coherence of breathing modes can be achieved in simulations for a perfect spatial arrangement of cells as initial condition, global disorder is observed in both three-dimensional experiments and simulations from realistic noisy initial conditions. The, erratic tip splitting events promoted by large amplitude oscillations contribute to maintaining the long-range array disorder, unlike in thin sample experiments where long-range coherence of oscillations is experimentally observable.Â«Â less
SOLA-DM: A numerical solution algorithm for transient three-dimensional flows
Wilson, T.L.; Nichols, B.D.; Hirt, C.W.; Stein, L.R.
1988-02-01
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.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Tourret, D.; Karma, A.; Clarke, A. J.; Gibbs, P. J.; Imhoff, S. D.
2015-06-11
We present a three-dimensional (3D) extension of a previously proposed multi-scale Dendritic Needle Network (DNN) approach for the growth of complex dendritic microstructures. Using a new formulation of the DNN dynamics equations for dendritic paraboloid-branches of a given thickness, one can directly extend the DNN approach to 3D modeling. We validate this new formulation against known scaling laws and analytical solutions that describe the early transient and steady-state growth regimes, respectively. Finally, we compare the predictions of the model to in situ X-ray imaging of Al-Cu alloy solidification experiments. The comparison shows a very good quantitative agreement between 3D simulationsmoreÂ Â» and thin sample experiments. It also highlights the importance of full 3D modeling to accurately predict the primary dendrite arm spacing that is significantly over-estimated by 2D simulations.Â«Â less
Three-Dimensional Electromagnetic High Frequency Axisymmetric Cavity Scars.
Warne, Larry K.; Jorgenson, Roy E.
2014-10-01
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
Three-dimensional Casimir piston for massive scalar fields
Lim, S.C. Teo, L.P.
2009-08-15
We consider Casimir force acting on a three-dimensional rectangular piston due to a massive scalar field subject to periodic, Dirichlet and Neumann boundary conditions. Exponential cut-off method is used to derive the Casimir energy. It is shown that the divergent terms do not contribute to the Casimir force acting on the piston, thus render a finite well-defined Casimir force acting on the piston. Explicit expressions for the total Casimir force acting on the piston is derived, which show that the Casimir force is always attractive for all the different boundary conditions considered. As a function of a - the distance from the piston to the opposite wall, it is found that the magnitude of the Casimir force behaves like 1/a{sup 4} when a{yields}0{sup +} and decays exponentially when a{yields}{infinity}. Moreover, the magnitude of the Casimir force is always a decreasing function of a. On the other hand, passing from massless to massive, we find that the effect of the mass is insignificant when a is small, but the magnitude of the force is decreased for large a in the massive case.
Parallel phase-sensitive three-dimensional imaging camera
Smithpeter, Colin L.; Hoover, Eddie R.; Pain, Bedabrata; Hancock, Bruce R.; Nellums, Robert O.
2007-09-25
An apparatus is disclosed for generating a three-dimensional (3-D) image of a scene illuminated by a pulsed light source (e.g. a laser or light-emitting diode). The apparatus, referred to as a phase-sensitive 3-D imaging camera utilizes a two-dimensional (2-D) array of photodetectors to receive light that is reflected or scattered from the scene and processes an electrical output signal from each photodetector in the 2-D array in parallel using multiple modulators, each having inputs of the photodetector output signal and a reference signal, with the reference signal provided to each modulator having a different phase delay. The output from each modulator is provided to a computational unit which can be used to generate intensity and range information for use in generating a 3-D image of the scene. The 3-D camera is capable of generating a 3-D image using a single pulse of light, or alternately can be used to generate subsequent 3-D images with each additional pulse of light.
Three-dimensional lattice Boltzmann model for magnetic reconnection
Mendoza, M.; Munoz, J. D.
2008-02-15
We develop a three-dimensional (3D) lattice Boltzmann model that recovers in the continuous limit the two-fluids theory for plasmas, and consequently includes the generalized Ohm's law. The model reproduces the magnetic reconnection process just by giving the right initial equilibrium conditions in the magnetotail, without any assumption on the resistivity in the diffusive region. In this model, the plasma is handled similar to two fluids with an interaction term, each one with distribution functions associated to a cubic lattice with 19 velocities (D3Q19). The electromagnetic fields are considered as a third fluid with an external force on a cubic lattice with 13 velocities (D3Q13). The model can simulate either viscous fluids in the incompressible limit or nonviscous compressible fluids, and successfully reproduces both the Hartmann flow and the magnetic reconnection in the magnetotail. The reconnection rate in the magnetotail obtained with this model lies between R=0.062 and R=0.073, in good agreement with the observations.
A novel three dimensional semimetallic MoS{sub 2}
Tang, Zhen-Kun; Zhang, Hui; Liu, Li-Min; Liu, Hao; Lau, Woon-Ming
2014-05-28
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.
Femtosecond laser three-dimensional micro- and nanofabrication
Sugioka, Koji; Cheng, Ya
2014-12-15
The rapid development of the femtosecond laser has revolutionized materials processing due to its unique characteristics of ultrashort pulse width and extremely high peak intensity. The short pulse width suppresses the formation of a heat-affected zone, which is vital for ultrahigh precision fabrication, whereas the high peak intensity allows nonlinear interactions such as multiphoton absorption and tunneling ionization to be induced in transparent materials, which provides versatility in terms of the materials that can be processed. More interestingly, irradiation with tightly focused femtosecond laser pulses inside transparent materials makes three-dimensional (3D) micro- and nanofabrication available due to efficient confinement of the nonlinear interactions within the focal volume. Additive manufacturing (stereolithography) based on multiphoton absorption (two-photon polymerization) enables the fabrication of 3D polymer micro- and nanostructures for photonic devices, micro- and nanomachines, and microfluidic devices, and has applications for biomedical and tissue engineering. Subtractive manufacturing based on internal modification and fabrication can realize the direct fabrication of 3D microfluidics, micromechanics, microelectronics, and photonic microcomponents in glass. These microcomponents can be easily integrated in a single glass microchip by a simple procedure using a femtosecond laser to realize more functional microdevices, such as optofluidics and integrated photonic microdevices. The highly localized multiphoton absorption of a tightly focused femtosecond laser in glass can also induce strong absorption only at the interface of two closely stacked glass substrates. Consequently, glass bonding can be performed based on fusion welding with femtosecond laser irradiation, which provides the potential for applications in electronics, optics, microelectromechanical systems, medical devices, microfluidic devices, and small satellites. This review paper describes the concepts and principles of femtosecond laser 3D micro- and nanofabrication and presents a comprehensive review on the state-of-the-art, applications, and the future prospects of this technology.
NON-BAROTROPIC LINEAR ROSSBY WAVE INSTABILITY IN THREE-DIMENSIONAL DISKS
Lin, Min-Kai
2013-03-10
Astrophysical disks with localized radial structure, such as protoplanetary disks containing dead zones or gaps due to disk-planet interaction, may be subject to the non-axisymmetric Rossby wave instability (RWI) that leads to vortex formation. The linear instability has recently been demonstrated in three-dimensional (3D) barotropic disks. It is the purpose of this study to generalize the 3D linear problem to include an energy equation, thereby accounting for baroclinity in three dimensions. Linear stability calculations are presented for radially structured, vertically stratified, geometrically thin disks with non-uniform entropy distribution in both directions. Polytropic equilibria are considered but adiabatic perturbations assumed. The unperturbed disk has a localized radial density bump, making it susceptible to the RWI. The linearized fluid equations are solved numerically as a partial differential equation eigenvalue problem. Emphasis on the ease of method implementation is given. It is found that when the polytropic index is fixed and adiabatic index increased, non-uniform entropy has negligible effect on the RWI growth rate, but pressure and density perturbation magnitudes near a pressure enhancement increase away from the midplane. The associated meridional flow is also qualitatively changed from homentropic calculations. Meridional vortical motion is identified in the nonhomentropic linear solution, as well as in a nonlinear global hydrodynamic simulation of the RWI in an initially isothermal disk evolved adiabatically. Numerical results suggest that buoyancy forces play an important role in the internal flow of Rossby vortices.
THREE-DIMENSIONAL SHAPE AND EVOLUTION OF TWO ERUPTIVE FILAMENTS
Li Ting; Zhang Jun; Yang Shuhong; Zhao Hui E-mail: zjun@nao.cas.c E-mail: v00975@phys.nthu.edu.t
2010-09-01
On 2009 September 26, a dramatic and large filament (LF) eruption and a small filament (SF) eruption were observed in the He II 304 A line by the two EUVI telescopes aboard the STEREO A and B spacecraft. The LF heads out into space and becomes the bright core of a gradual coronal mass ejection (CME), while the eruption of the SF is characterized by motions of the filament materials. Using stereoscopic analysis of EUVI data, we reconstruct the three-dimensional shape and evolution of two eruptive filaments. For the first time, we investigate the true velocities and accelerations of 12 points along the axis of the LF, and find that the velocity and acceleration vary with the measured location. The highest points among the 12 points are the fastest in the first half hour, and then the points at the low-latitude leg of the LF become the fastest. For the SF, it is an asymmetric whip-like filament eruption, and the downward motions of the material lead to the disappearance of the former high-latitude endpoint and the formation of a new low-latitude endpoint. Based on the temporal evolution of the two filaments, we infer that the two filaments lie in the same filament channel. By combining the EUVI, COR1, and COR2 data of STEREO A together, we find that there is no impulsive or fast acceleration in this event. It displays a weak and persistent acceleration for more than 17 hr. The average velocity and acceleration of the LF are 101.8 km s{sup -1} and 2.9 m s{sup -2}, respectively. The filament eruptions are associated with a slow CME with an average velocity of 177.4 km s{sup -1}. The velocity of the CME is nearly 1.6 times as large as that of the filament material. This event is one example of a gradual filament eruption associated with a gradual CME. In addition, the moving direction of the LF changes from a non-radial to a nearly radial direction with a variation of inclination angle of nearly 38.{sup 0}2.
The impact of disorder on charge transport in three dimensional quantum dot
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resonant tunneling structures (Journal Article) | SciTech Connect The impact of disorder on charge transport in three dimensional quantum dot resonant tunneling structures Citation Details In-Document Search Title: The impact of disorder on charge transport in three dimensional quantum dot resonant tunneling structures Efficient iso-entropic energy filtering of electronic waves can be realized through nanostructures with three dimensional confinement, such as quantum dot resonant tunneling
Three-dimensional Dendritic Needle Network model with application to Al-Cu
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directional solidification experiments (Journal Article) | SciTech Connect Journal Article: Three-dimensional Dendritic Needle Network model with application to Al-Cu directional solidification experiments Citation Details In-Document Search Title: Three-dimensional Dendritic Needle Network model with application to Al-Cu directional solidification experiments We present a three-dimensional (3D) extension of a previously proposed multi-scale Dendritic Needle Network (DNN) approach for the
Three-dimensional tokamak equilibria in the presence of resonant field
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errors (Technical Report) | SciTech Connect Technical Report: Three-dimensional tokamak equilibria in the presence of resonant field errors Citation Details In-Document Search Title: Three-dimensional tokamak equilibria in the presence of resonant field errors Numerical solutions are described for three-dimensional MHD equilibria in the presence of resonant magnetic field perturbations. The effects of a realistic spectrum of resonant field errors are calculated for a range of current
Three-dimensional tokamak equilibria in the presence of resonant field
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errors (Technical Report) | SciTech Connect Three-dimensional tokamak equilibria in the presence of resonant field errors Citation Details In-Document Search Title: Three-dimensional tokamak equilibria in the presence of resonant field errors Numerical solutions are described for three-dimensional MHD equilibria in the presence of resonant magnetic field perturbations. The effects of a realistic spectrum of resonant field errors are calculated for a range of current profiles. It is found
Laplace-Runge-Lenz vector for arbitrary spin
Nikitin, A. G.
2013-12-15
A countable set of superintegrable quantum mechanical systems is presented which admit the dynamical symmetry with respect to algebra so(4). This algebra is generated by the Laplace-Runge-Lenz vector generalized to the case of arbitrary spin. The presented systems describe neutral particles with non-trivial multipole momenta. Their spectra can be found algebraically like in the case of hydrogen atom. Solutions for the systems with spins 1/2 and 1 are presented explicitly, solutions for spin 3/2 can be expressed via solutions of an ordinary differential equation of first order. A more extended version of this paper including detailed calculations is published as an e-print arXiv:1308.4279.
Kondo-like zero-bias conductance anomaly in a three-dimensional...
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Journal Article: Kondo-like zero-bias conductance anomaly in a three-dimensional topological insulator nanowire Citation ... Type: Accepted Manuscript Journal Name: Scientific Reports ...
Three-dimensional Plasmas R. L. Dewar; P. Cuthbert; R. Ball 70...
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of Three-dimensional Plasmas R. L. Dewar; P. Cuthbert; R. Ball 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY;...
Three-dimensional V p /V s variations for the Coso region, California...
the Pleistocene volcanics of the Coso Range. In order to learn more about the physical nature of these colocated anomalies, a tomographic inversion for the three-dimensional...
Dynamic control of polarization-inverted modes in three-dimensionally...
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(NPs), we clarified that spherical silver NPs can be optically trapped and aligned ... POLARIZATION; RADIATIVE DECAY; SENSORS; SILVER; THREE-DIMENSIONAL LATTICES; TRAPPING; ...
Chitsazi, Mahboobeh; Maraghechi, B.; Rouhani, M. H.
2010-10-15
The effect of prebunching of the electron beam and tapering of the wiggler amplitude on the harmonic upconversion in free-electron laser amplifier is studied in three dimensions. A set of coupled nonlinear first-order differential equations that describe the three-dimensional simulation of the system is solved numerically. This set of equation describes self-consistently the longitudinal spatial dependence of radiation waists, curvatures, and amplitudes together with the evaluation of the electron beam. The analysis is related to extreme ultraviolet and x-ray emission. In addition to uniform beam, prebunched electron beam has also been studied. The effect of sinusoidal distribution of entry times for the electron beam on the evolution of radiation is compared with uniform distribution. It is shown that prebunching reduces the saturation length substantially. For efficiency enhancement, the wiggler is set to decrease linearly when the radiation of the third harmonic saturates. The optimum starting point and the slope of tapering of the amplitude of the wiggler are found by a successive run of the code. It was found that tapering can increase the saturated power of the third harmonic considerably.
About vacuum solutions of Einstein's field equations with flat three-dimensional hypersurfaces
Wolf, T.
1986-09-01
The class of vacuum space-times with a family of flat three-slices and a traceless tensor of exterior curvature K-italic/sub a-italic//sub b-italic/ is examined. Metrics without symmetry and solutions describing gravitational radiation are obtained. It turns out that there is a correlation between rank (K-italic/sub a-italic//sub b-italic/) and the Petrov type. Although the resulting solutions are already known, the richness of the class of space-times with flat slices becomes obvious. An example is given of a metric with one-parameter manifold of families of flat slices.
Diffusion coefficient of three-dimensional Yukawa liquids
Dzhumagulova, K. N.; Ramazanov, T. S.; Masheeva, R. U.
2013-11-15
The purpose of this work is an investigation of the diffusion coefficient of the dust component in complex plasma. The computer simulation of the Yukawa liquids was made on the basis of the Langevin equation, which takes into account the influence of buffer plasma on the dust particles dynamics. The Green–Kubo relation was used to calculate the diffusion coefficient. Calculations of the diffusion coefficient for a wide range of the system parameters were performed. Using obtained numerical data, we constructed the interpolation formula for the diffusion coefficient. We also show that the interpolation formula correctly describes experimental data obtained under microgravity conditions.
Iskander, S.K.
1981-02-01
Two finite element (FE) approaches were used to calculate opening mode I stress intensity factors (K/sub I/) in two- or three-dimensional (2-D and 3-D) problems for the Heavy-Section Steel Technology (HSST) program. For problems that can be modeled in two dimensions, two techniques were used. One of these may be termed an ''energy release rate'' technique, and the other is based on the classical near-tip displacement and stress field equations. For three-dimensional problems, only the latter technique was used. In the energy release technique, K/sub I/ is calculated as the change in potential energy of the structure due to a small change in crack length. The potential energy is calculated by the FE method but without completely solving the system of linear equations for the displacements. Furthermore, the system of linear equations is only slightly perturbed by the change in crack length and, therefore, many computations need not be repeated for the second structure with the slight change in crack length. Implementation of these last two items has resulted in considerable savings in the calculation of K/sub I/ as compared to two complete FE analyses. These ideas are incorporated in the FMECH code. The accuracy of the methods has been checked by comparing the results of the two approaches with each other and with closed form solutions. It is estimated that the accuracy of the results is about +-5%.
Gent, F. A.; Erdélyi, R.; Fedun, V.
2014-07-01
A system of multiple open magnetic flux tubes spanning the solar photosphere and lower corona is modeled analytically, within a realistic stratified atmosphere subject to solar gravity. This extends results for a single magnetic flux tube in magnetohydrostatic equilibrium, described in Gent et al. Self-similar magnetic flux tubes are combined to form magnetic structures, which are consistent with high-resolution observations. The observational evidence supports the existence of strands of open flux tubes and loops persisting in a relatively steady state. Self-similar magnetic flux tubes, for which an analytic solution to the plasma density and pressure distribution is possible, are combined. We calculate the appropriate balancing forces, applying to the equations of momentum and energy conservation to preserve equilibrium. Multiplex flux tube configurations are observed to remain relatively stable for up to a day or more, and it is our aim to apply our model as the background condition for numerical studies of energy transport mechanisms from the solar surface to the corona. We apply magnetic field strength, plasma density, pressure, and temperature distributions consistent with observational and theoretical estimates for the lower solar atmosphere. Although each flux tube is identical in construction apart from the location of the radial axis, combinations can be applied to generate a non-axisymmetric magnetic field with multiple non-uniform flux tubes. This is a considerable step forward in modeling the realistic magnetized three-dimensional equilibria of the solar atmosphere.
Current singularities at quasi-separatrix layers and three-dimensional magnetic nulls
Craig, I. J. D.; Effenberger, Frederic
2014-11-10
The open problem of how singular current structures form in line-tied, three-dimensional magnetic fields is addressed. A Lagrangian magneto-frictional relaxation method is employed to model the field evolution toward the final near-singular state. Our starting point is an exact force-free solution of the governing magnetohydrodynamic equations that is sufficiently general to allow for topological features like magnetic nulls to be inside or outside the computational domain, depending on a simple set of parameters. Quasi-separatrix layers (QSLs) are present in these structures and, together with the magnetic nulls, they significantly influence the accumulation of current. It is shown that perturbations affecting the lateral boundaries of the configuration lead not only to collapse around the magnetic null but also to significant QSL currents. Our results show that once a magnetic null is present, the developing currents are always attracted to that specific location and show a much stronger scaling with resolution than the currents that form along the QSL. In particular, the null-point scalings can be consistent with models of 'fast' reconnection. The QSL currents also appear to be unbounded but give rise to weaker singularities, independent of the perturbation amplitude.
Schiek, Richard (Albuquerque, NM)
2006-06-20
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.
Defect propagation in one-, two-, and three-dimensional compounds doped by
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magnetic atoms (Journal Article) | SciTech Connect Defect propagation in one-, two-, and three-dimensional compounds doped by magnetic atoms Citation Details In-Document Search Title: Defect propagation in one-, two-, and three-dimensional compounds doped by magnetic atoms Inelastic neutron scattering experiments were performed to study manganese(II) dimer excitations in the diluted one-, two-, and three-dimensional compounds CsMnxMg1-xBr3, K2MnxZn1-xF4, and KMnxZn1-xF3 (xâ‰¤0.10),
Yamazaki, Kazuo
2014-03-15
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, â€śOn the regularity of weak solutions to the magnetohydrodynamic equations,â€ť J. Differ. Equ. 213(2), 234â€“254 (2005); Y. Zhou, â€śRemarks on regularities for the 3D MHD equations,â€ť Discrete Contin. Dyn. Syst. 12(5), 881â€“886 (2005)].
Trampedach, Regner; Asplund, Martin; Collet, Remo; Nordlund, Ake
2013-05-20
Present grids of stellar atmosphere models are the workhorses in interpreting stellar observations and determining their fundamental parameters. These models rely on greatly simplified models of convection, however, lending less predictive power to such models of late-type stars. We present a grid of improved and more reliable stellar atmosphere models of late-type stars, based on deep, three-dimensional (3D), convective, stellar atmosphere simulations. This grid is to be used in general for interpreting observations and improving stellar and asteroseismic modeling. We solve the Navier Stokes equations in 3D and concurrent with the radiative transfer equation, for a range of atmospheric parameters, covering most of stellar evolution with convection at the surface. We emphasize the use of the best available atomic physics for quantitative predictions and comparisons with observations. We present granulation size, convective expansion of the acoustic cavity, and asymptotic adiabat as functions of atmospheric parameters.
Probing the role of sequence in the assembly of three-dimensional...
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Probing the role of sequence in the assembly of three-dimensional DNA crystals Citation Details In-Document Search Title: Probing the role of sequence in the assembly of ...
Alaska Maximum Number of Active Crews Engaged in Three-Dimensional...
Gasoline and Diesel Fuel Update (EIA)
Three-Dimensional Seismic Surveying (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 2000's 9 2 11 6...
Tewari, A.; Gokhale, A.M.
2000-03-01
Three-dimensional digital image processing is useful for reconstruction of microstructural volume from a stack of serial sections. Application of this technique is demonstrated via reconstruction of a volume segment of the liquid-phase sintered microstructure of a tungsten heavy alloy processed in the microgravity environment of NASA's space shuttle, Columbia. Ninety serial sections (approximately one micrometer apart) were used for reconstruction of the three-dimensional microstructure. The three-dimensional microstructural reconstruction clearly revealed that the tungsten grains are almost completely connected in three-dimensional space. Both the matrix and the grains are topologically co-continuous, although the alloy was liquid-phase sintered in microgravity. Therefore, absence of gravity did not produced a microstructure consisting of discrete isolated W grains uniformly dispersed in the liquid Ni-Fe alloy matrix at the sintering temperature.
Three-Dimensional Topological Insulators in I - III - VI 2 and...
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and II - IV - V 2 Chalcopyrite Semiconductors Citation Details In-Document Search Title: Three-Dimensional Topological Insulators in I - III - VI 2 and II - IV - V 2 Chalcopyrite ...
Monolithic three-dimensional electrochemical energy storage system on aerogel or nanotube scaffold
Farmer, Joseph C; Stadermann, Michael
2013-11-12
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
2014-07-15
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.
Dynamic control of polarization-inverted modes in three-dimensionally
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trapped multiple nanogaps (Journal Article) | SciTech Connect SciTech Connect Search Results Journal Article: Dynamic control of polarization-inverted modes in three-dimensionally trapped multiple nanogaps Citation Details In-Document Search Title: Dynamic control of polarization-inverted modes in three-dimensionally trapped multiple nanogaps We propose a guiding principle for the dynamic control of polarization-inverted modes in multiple nanogaps for unconventional optical transitions of
Kondo-like zero-bias conductance anomaly in a three-dimensional topological
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insulator nanowire (Journal Article) | SciTech Connect Journal Article: Kondo-like zero-bias conductance anomaly in a three-dimensional topological insulator nanowire Citation Details In-Document Search Title: Kondo-like zero-bias conductance anomaly in a three-dimensional topological insulator nanowire Zero-bias anomalies in topological nanowires have recently captured significant attention, as they are possible signatures of Majorana modes. Yet there are many other possible origins of
Detailed High-Resolution Three-Dimensional Simulations of OMEGA Separated
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Reactants Inertial Confinement Fusion Experiments (Conference) | SciTech Connect Detailed High-Resolution Three-Dimensional Simulations of OMEGA Separated Reactants Inertial Confinement Fusion Experiments Citation Details In-Document Search Title: Detailed High-Resolution Three-Dimensional Simulations of OMEGA Separated Reactants Inertial Confinement Fusion Experiments Authors: Haines, Brian Michael [1] ; Grim, Gary P. [1] ; Fincke, James R. [1] ; Shah, Rahul C. [1] ; Forrest, Chad [2] ;
Method and Apparatus for Three-Dimensional Carbon Fiber Production - Energy
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Innovation Portal Hydrogen and Fuel Cell Hydrogen and Fuel Cell Advanced Materials Advanced Materials Find More Like This Return to Search Method and Apparatus for Three-Dimensional Carbon Fiber Production DOE Grant Recipients Contact GRANT About This Technology Technology Marketing Summary UCF researchers have discovered a method for producing three-dimensional carbon fibers. These novel fibers have a surface area approximately two orders of magnitude greater than the surface area of
Comparisons Of Two- And Three-Dimensional Convection In Type I X-Ray Bursts
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Zingale, M.; Malone, C. M.; Nonaka, A.; Almgren, A. S.; Bell, J. B.
2015-07-01
We perform the first detailed three-dimensional simulation of low Mach number convection preceding runaway thermonuclear ignition in a mixed H/He X-ray burst. Our simulations include a moderate-sized, approximate network that captures hydrogen and helium burning up through rp-process breakout. We look at the difference between two- and three-dimensional convective fields, including the details of the turbulent convection.
The Three-Dimensional Structural Basis of Type II Hyperprolinemia (Journal
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Article) | SciTech Connect The Three-Dimensional Structural Basis of Type II Hyperprolinemia Citation Details In-Document Search Title: The Three-Dimensional Structural Basis of Type II Hyperprolinemia 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
Three-Dimensional Modeling and Simulation of DNA Hybridization Kinetics and
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Mass Transport as Functions of Temperature in a Microfluidic Channel. (Journal Article) | SciTech Connect Three-Dimensional Modeling and Simulation of DNA Hybridization Kinetics and Mass Transport as Functions of Temperature in a Microfluidic Channel. Citation Details In-Document Search Title: Three-Dimensional Modeling and Simulation of DNA Hybridization Kinetics and Mass Transport as Functions of Temperature in a Microfluidic Channel. Abstract not provided. Authors: Manginell, Ronald P ;
Three-Dimensional Modeling of the Reactive Transport of CO2 and Its Impact
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on Geomechanical Properties of Reservoir Rocks and Seals (Journal Article) | SciTech Connect Three-Dimensional Modeling of the Reactive Transport of CO2 and Its Impact on Geomechanical Properties of Reservoir Rocks and Seals Citation Details In-Document Search Title: Three-Dimensional Modeling of the Reactive Transport of CO2 and Its Impact on Geomechanical Properties of Reservoir Rocks and Seals This article develops a novel multiscale modeling approach to analyze CO2 reservoirs using
Three-Dimensional Topological Insulators in I - III - VI 2 and II -
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IV - V 2 Chalcopyrite Semiconductors (Journal Article) | SciTech Connect Three-Dimensional Topological Insulators in I - III - VI 2 and II - IV - V 2 Chalcopyrite Semiconductors Citation Details In-Document Search Title: Three-Dimensional Topological Insulators in I - III - VI 2 and II - IV - V 2 Chalcopyrite Semiconductors Authors: Feng, Wanxiang ; Xiao, Di ; Ding, Jun ; Yao, Yugui Publication Date: 2011-01-05 OSTI Identifier: 1101341 Type: Publisher's Accepted Manuscript Journal Name:
Three-dimensional Numerical Analysis on Blade Response of Vertical Axis
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Tidal Current Turbine Under Operational Condition (Journal Article) | SciTech Connect Three-dimensional Numerical Analysis on Blade Response of Vertical Axis Tidal Current Turbine Under Operational Condition Citation Details In-Document Search Title: Three-dimensional Numerical Analysis on Blade Response of Vertical Axis Tidal Current Turbine Under Operational Condition Tidal power as a large-scale renewable source of energy has been receiving significant attention recently because of its
Three-dimensionally scaffolded Co3O4 nanosheet anodes with high rate
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performance (Journal Article) | SciTech Connect Three-dimensionally scaffolded Co3O4 nanosheet anodes with high rate performance Citation Details In-Document Search This content will become publicly available on September 1, 2017 Title: Three-dimensionally scaffolded Co3O4 nanosheet anodes with high rate performance Authors: Liu, Jinyun ; Kelly, Sean J. ; Epstein, Eric S. ; Pan, Zeng ; Huang, Xingjiu ; Liu, Jinhuai ; Braun, Paul V. Publication Date: 2015-12-01 OSTI Identifier: 1253197
Transient behavior of a supersonic three-dimensional micronozzle with an
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intersecting capillary (Journal Article) | SciTech Connect Transient behavior of a supersonic three-dimensional micronozzle with an intersecting capillary Citation Details In-Document Search This content will become publicly available on February 16, 2017 Title: Transient behavior of a supersonic three-dimensional micronozzle with an intersecting capillary Authors: Matlis, N. H. [1] Search SciTech Connect for author "Matlis, N. H." Search SciTech Connect for ORCID
Jiang, Yan-Fei; Stone, James M.; Davis, Shane W.
2014-12-01
We study super-Eddington accretion flows onto black holes using a global three-dimensional radiation magneto-hydrodynamical simulation. We solve the time-dependent radiative transfer equation for the specific intensities to accurately calculate the angular distribution of the emitted radiation. Turbulence generated by the magneto-rotational instability provides self-consistent angular momentum transfer. The simulation reaches inflow equilibrium with an accretion rate âĽ220 L {sub Edd}/c {sup 2} and forms a radiation-driven outflow along the rotation axis. The mechanical energy flux carried by the outflow is âĽ20% of the radiative energy flux. The total mass flux lost in the outflow is about 29% of the net accretion rate. The radiative luminosity of this flow is âĽ10 L {sub Edd}. This yields a radiative efficiency âĽ4.5%, which is comparable to the value in a standard thin disk model. In our simulation, vertical advection of radiation caused by magnetic buoyancy transports energy faster than photon diffusion, allowing a significant fraction of the photons to escape from the surface of the disk before being advected into the black hole. We contrast our results with the lower radiative efficiencies inferred in most models, such as the slim disk model, which neglect vertical advection. Our inferred radiative efficiencies also exceed published results from previous global numerical simulations, which did not attribute a significant role to vertical advection. We briefly discuss the implications for the growth of supermassive black holes in the early universe and describe how these results provided a basis for explaining the spectrum and population statistics of ultraluminous X-ray sources.
A NEW THREE-DIMENSIONAL SOLAR WIND MODEL IN SPHERICAL COORDINATES WITH A SIX-COMPONENT GRID
Feng, Xueshang; Zhang, Man; Zhou, Yufen
2014-09-01
In this paper, we introduce a new three-dimensional magnetohydrodynamics numerical model to simulate the steady state ambient solar wind from the solar surface to 215 R {sub s} or beyond, and the model adopts a splitting finite-volume scheme based on a six-component grid system in spherical coordinates. By splitting the magnetohydrodynamics equations into a fluid part and a magnetic part, a finite volume method can be used for the fluid part and a constrained-transport method able to maintain the divergence-free constraint on the magnetic field can be used for the magnetic induction part. This new second-order model in space and time is validated when modeling the large-scale structure of the solar wind. The numerical results for Carrington rotation 2064 show its ability to produce structured solar wind in agreement with observations.
Long, Gregory T.; Brundage, Aaron L.; Wixom, Ryan R.; Tappan, Alexander Smith
2009-08-01
Three-dimensional shock simulations of energetic materials have been conducted to improve our understanding of initiation at the mesoscale. Vapor-deposited films of PETN and pressed powders of HNS were characterized with a novel three-dimensional nanotomographic technique. Detailed microstructures were constructed experimentally from a stack of serial electron micrographs obtained by successive milling and imaging in a dual-beam FIB/SEM. These microstructures were digitized and imported into a multidimensional, multimaterial Eulerian shock physics code. The simulations provided insight into the mechanisms of pore collapse in PETN and HNS samples with distinctly different three-dimensional pore morphology and distribution. This modeling effort supports investigations of microscale explosive phenomenology and elucidates mechanisms governing initiation of secondary explosives.
Karasick, Michael S.; Strip, David R.
1996-01-01
A parallel computing system is described that comprises a plurality of uniquely labeled, parallel processors, each processor capable of modelling a three-dimensional object that includes a plurality of vertices, faces and edges. The system comprises a front-end processor for issuing a modelling 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 modelling 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.
Atomic-scale observation of dynamical fluctuation and three-dimensional structure of gold clusters
Li, Junjie; Yin, Deqiang; Chen, Chunlin; Lin, Liyang; Wang, Zhongchang; Li, Qiang; Sun, Rong; Huang, Sumei
2015-02-28
Unravelling three-dimensional structures and dynamical fluctuation of metal nanoclusters is critical to understanding reaction process and the origin of catalytic activity in many heterogeneous catalytic systems. We obtain three-dimensional structures of ultra-small Au clusters by combining aberration-corrected scanning transmission electron microscopy, density functional theory calculations, and imaging simulations. The configurations of unique Au clusters are revealed at the atomic scale and the corresponding electronic states are given. The sequential observations reveal a transition of ultra-small Au clusters with about 25 atoms from a near-square to an elongated structure. We also find a transition from two dimensions to three dimensions for the Au clusters. The obtained three-dimensional geometry and associated electronic states help to clarify atomistic mechanism of shape- and number-dependent catalytic activities of Au clusters.
Karasick, M.S.; Strip, D.R.
1996-01-30
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.
Lim, Hojun; Owen, Steven J.; Abdeljawad, Fadi F.; Hanks, Byron; Battaile, Corbett Chandler
2015-09-01
In order to better incorporate microstructures in continuum scale models, we use a novel finite element (FE) meshing technique to generate three-dimensional polycrystalline aggregates from a phase field grain growth model of grain microstructures. The proposed meshing technique creates hexahedral FE meshes that capture smooth interfaces between adjacent grains. Three dimensional realizations of grain microstructures from the phase field model are used in crystal plasticity-finite element (CP-FE) simulations of polycrystalline a -iron. We show that the interface conformal meshes significantly reduce artificial stress localizations in voxelated meshes that exhibit the so-called "wedding cake" interfaces. This framework provides a direct link between two mesoscale models - phase field and crystal plasticity - and for the first time allows mechanics simulations of polycrystalline materials using three-dimensional hexahedral finite element meshes with realistic topological features.
Nonlinear electron-magnetohydrodynamic simulations of three dimensional current shear instability
Jain, Neeraj; Das, Amita; Sengupta, Sudip; Kaw, Predhiman
2012-09-15
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.
Grid Generator for Two, Three-dimensional Finite Element Subsurface Flow Models
Energy Science and Technology Software Center (OSTI)
1993-04-28
GRIDMAKER serves as a preprocessor for finite element models in solving two- and three-dimensional subsurface flow and pollutant transport problems. It is designed to generate three-point triangular or four-point quadrilateral elements for two-dimensional domains and eight-point hexahedron elements for three-dimensional domains. A two-dimensional domain of an aquifer with a variable depth layer is treated as a special case for depth-integrated two-dimensional, finite element subsurface flow models. The program accommodates the need for aquifers with heterogeneousmoreÂ Â» systems by identifying the type of material in each element.Â«Â less
Ray tracing a three-dimensional scene using a hierarchical data structure
Wald, Ingo; Boulos, Solomon; Shirley, Peter
2012-09-04
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.
Crystallization of a self-assembled three-dimensional DNA nanostructure
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Crystallization of a self-assembled three-dimensional DNA nanostructure Authors: Rendek, K.N., Fromme, R., Grotjohann, I., Fromme, P. Title: Crystallization of a self-assembled three-dimensional DNA nanostructure Source: Acta Crystallogr. Sect. F Year: 2013 Volume: F69 Pages: 141-146 ABSTRACT: The powerful and specific molecular-recognition system present in the base-pairing of DNA allows for the design of a plethora of nanostructures. In this work, the crystallization of a self-assembling
Three dimensional time-gated tracking of non-blinking quantum dots in live
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cells (Journal Article) | SciTech Connect Three dimensional time-gated tracking of non-blinking quantum dots in live cells Citation Details In-Document Search Title: Three dimensional time-gated tracking of non-blinking quantum dots in live cells Single particle tracking has provided a wealth of information about biophysical processes such as motor protein transport and diffusion in cell membranes. However, motion out of the plane of the microscope or blinking of the fluorescent probe used
Three dimensional time-gated tracking of non-blinking quantum dots in live
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cells (Journal Article) | SciTech Connect Three dimensional time-gated tracking of non-blinking quantum dots in live cells Citation Details In-Document Search Title: Three dimensional time-gated tracking of non-blinking quantum dots in live cells Ă— You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional
Three-dimensional simulation of H-mode plasmas with localized divertor
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impurity injection on Alcator C-Mod using the edge transport code EMC3-EIRENE (Journal Article) | SciTech Connect Three-dimensional simulation of H-mode plasmas with localized divertor impurity injection on Alcator C-Mod using the edge transport code EMC3-EIRENE Citation Details In-Document Search Title: Three-dimensional simulation of H-mode plasmas with localized divertor impurity injection on Alcator C-Mod using the edge transport code EMC3-EIRENE Experiments in Alcator C-Mod to assess
Three-dimensional simulation of H-mode plasmas with localized divertor
Office of Scientific and Technical Information (OSTI)
impurity injection on Alcator C-Mod using the edge transport code EMC3-EIRENEa) (Journal Article) | SciTech Connect Three-dimensional simulation of H-mode plasmas with localized divertor impurity injection on Alcator C-Mod using the edge transport code EMC3-EIRENEa) Citation Details In-Document Search Title: Three-dimensional simulation of H-mode plasmas with localized divertor impurity injection on Alcator C-Mod using the edge transport code EMC3-EIRENEa) Authors: Lore, J. D. [1] ; Reinke,
Ashraf, M. Bilal; Hayat, T.; Shehzad, S. A.; Alsaedi, A.
2015-02-15
Three dimensional radiative flow of Maxwell fluid over an inclined stretching surface with convective boundary condition is investigated. Heat and mass transfer analysis is taken into account with thermophoresis effects. Similarity transformations are utilized to reduce the partial differential equations into ordinary differential equations. Series solutions of velocity, temperature and concentration are developed. Influence of different parameters Biot number, therrmophoretic parameter, Deborah number, ratio parameter, inclined stretching angle, radiation parameter, mixed convection parameter and concentration buoyancy parameter on the non-dimensional velocity components, temperature and concentration are plotted and discussed in detail. Physical quantities of interests are tabulated and examined.
THREE-DIMENSIONAL MOVING-MESH SIMULATIONS OF GALACTIC CENTER CLOUD G2
Anninos, Peter; Murray, Stephen D.; Fragile, P. Chris; Wilson, Julia
2012-11-10
Using three-dimensional, moving-mesh simulations, we investigate the future evolution of the recently discovered gas cloud G2 traveling through the galactic center. We consider the case of a spherical cloud initially in pressure equilibrium with the background. Our suite of simulations explores the following parameters: the equation of state, radial profiles of the background gas, and start times for the evolution. Our primary focus is on how the fate of this cloud will affect the future activity of Sgr A*. From our simulations we expect an average feeding rate in the range of (5-19) Multiplication-Sign 10{sup -8} M {sub Sun} yr{sup -1} beginning in 2013 and lasting for at least 7 years (our simulations stop in year 2020). The accretion varies by less than a factor of three on timescales {<=}1 month, and shows no more than a factor of 10 difference between the maximum and minimum observed rates within any given model. These rates are comparable to the current estimated accretion rate in the immediate vicinity of Sgr A*, although they represent only a small ({approx}< 5%) increase over the current expected feeding rate at the effective inner boundary of our simulations (r = 750, R{sub S} Almost-Equal-To 10{sup 15} cm), where R{sub S} is the Schwarzschild radius of the black hole. Therefore, the breakup of cloud G2 may have only a minimal effect on the brightness and variability of Sgr A* over the next decade. This is because current models of the galactic center predict that most of the gas will be caught up in outflows. However, if the accreted G2 material can remain cold, it may not mix well with the hot, diffuse background gas, and instead accrete efficiently onto Sgr A*. Further observations of G2 will give us an unprecedented opportunity to test this idea. The breakup of the cloud itself may also be observable. By tracking the amount of cloud energy that is dissipated during our simulations, we are able to get a rough estimate of the luminosity associated with its tidal disruption; we find values of a few 10{sup 36} erg s{sup -1}.
Modeling Dispersion of Chemical-Biological Agents in Three Dimensional Living Space
William S. Winters
2002-02-01
This report documents a series of calculations designed to demonstrate Sandia's capability in modeling the dispersal of chemical and biological agents in complex three-dimensional spaces. The transport of particles representing biological agents is modeled in a single room and in several connected rooms. The influence of particle size, particle weight and injection method are studied.
Photodeposition Method For Fabricating A Three-Dimensional, Patterned Polymer Microstructure
Walt, David R.; Healey, Brian G.
2001-03-13
The present invention is a photodeposition methodology for fabricating a three-dimensional patterned polymer microstructure. A variety of polymeric structures can be fabricated on solid substrates using unitary fiber optic arrays for light delivery. The methodology allows micrometer-scale photopatterning for the fabricated structures using masks substantially larger than the desired dimensions of the microstructure.
Apical polarity in three-dimensional culture systems: where to now?
Inman, J.L.; Bissell, Mina
2010-01-21
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.
Borhanian, J.; Shahmansouri, M.
2013-01-15
A theoretical investigation is carried out to study the existence and characteristics of propagation of dust-acoustic (DA) waves in an electron-depleted dusty plasma with two-temperature ions, which are modeled by kappa distribution functions. A three-dimensional cylindrical Kadomtsev-Petviashvili equation governing evolution of small but finite amplitude DA waves is derived by means of a reductive perturbation method. The influence of physical parameters on solitary wave structure is examined. Furthermore, the energy integral equation is used to study the existence domains of the localized structures. It is found that the present model can be employed to describe the existence of positive as well as negative polarity DA solitary waves by selecting special values for parameters of the system, e.g., superthermal index of cold and/or hot ions, cold to hot ion density ratio, and hot to cold ion temperature ratio. This model may be useful to understand the excitation of nonlinear DA waves in astrophysical objects.
Computational analysis of a three-dimensional High-Velocity Oxygen-Fuel (HVOF) Thermal Spray torch
Hassan, B.; Lopez, A.R.; Oberkampf, W.L.
1995-07-01
An analysis of a High-Velocity Oxygen-Fuel Thermal Spray torch is presented using computational fluid dynamics (CFD). Three-dimensional CFD results are presented for a curved aircap used for coating interior surfaces such as engine cylinder bores. The device analyzed is similar to the Metco Diamond Jet Rotating Wire torch, but wire feed is not simulated. To the authors` knowledge, these are the first published 3-D results of a thermal spray device. The feed gases are injected through an axisymmetric nozzle into the curved aircap. Argon is injected through the center of the nozzle. Pre-mixed propylene and oxygen are introduced from an annulus in the nozzle, while cooling air is injected between the nozzle and the interior wall of the aircap. The combustion process is modeled assuming instantaneous chemistry. A standard, two-equation, K-{var_epsilon} turbulence model is employed for the turbulent flow field. An implicit, iterative, finite volume numerical technique is used to solve the coupled conservation of mass, momentum, and energy equations for the gas in a sequential manner. Flow fields inside and outside the aircap are presented and discussed.
Experimental Realization of a Three-Dimensional Topological Insulator, Bi 2Te3
Siemons, W.
2010-02-24
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.
Frahm, Jan-Michael; Pollefeys, Marc Andre Leon; Gallup, David Robert
2015-12-08
Methods of generating a three dimensional representation of an object in a reference plane from a depth map including distances from a reference point to pixels in an image of the object taken from a reference point. Weights are assigned to respective voxels in a three dimensional grid along rays extending from the reference point through the pixels in the image based on the distances in the depth map from the reference point to the respective pixels, and a height map including an array of height values in the reference plane is formed based on the assigned weights. An n-layer height map may be constructed by generating a probabilistic occupancy grid for the voxels and forming an n-dimensional height map comprising an array of layer height values in the reference plane based on the probabilistic occupancy grid.
Modelling of multistage selective photoionisation in a three-dimensional cavity
Golyatina, R I; Tkachev, Aleksei N; Yakovlenko, Sergei I
1998-08-31
An analysis is made of physical models of selective three-stage photoionisation of a vapour in a three-dimensional cavity. These models have been used in theoretical analyses of preparation of significant amounts of highly enriched {sup 168}Yb by the AVLIS (atomic-vapour laser isotope separation) method. A comparison of the model predictions with experiments shows that a three-dimensional model ignoring the absorption of laser radiation in a medium describes well the experimental results obtained for the second and third ionisation stages. The first excitation stage is described satisfactorily by a model in which absorption is included. A comparison of the calculated and experimental results is used to find the coefficient (65%) representing ion extraction from a laser plasma. (laser applications and other topics in quantum electronics)
Reversible gelling culture media for in-vitro cell culture in three-dimensional matrices
An, Yuehuei H.; Mironov, Vladimir A.; Gutowska, Anna
2000-01-01
A gelling cell culture medium useful for forming a three dimensional matrix for cell culture in vitro is prepared by copolymerizing an acrylamide derivative with a hydrophilic comonomer to form a reversible (preferably thermally reversible) gelling linear random copolymer in the form of a plurality of linear chains having a plurality of molecular weights greater than or equal to a minimum gelling molecular weight cutoff, mixing the copolymer with an aqueous solvent to form a reversible gelling solution and adding a cell culture medium to the gelling solution to form the gelling cell culture medium. Cells such as chondrocytes or hepatocytes are added to the culture medium to form a seeded culture medium, and temperature of the medium is raised to gel the seeded culture medium and form a three dimensional matrix containing the cells. After propagating the cells in the matrix, the cells may be recovered by lowering the temperature to dissolve the matrix and centrifuging.
Micrometer-scale fabrication of complex three dimensional lattice + basis structures in silicon
Burckel, D. Bruce; Resnick, Paul J.; Finnegan, Patrick S.; Sinclair, Michael B.; Davids, Paul S.
2015-01-01
A complementary metal oxide semiconductor (CMOS) compatible version of membrane projection lithography (MPL) for fabrication of micrometer-scale three-dimensional structures is presented. The approach uses all inorganic materials and standard CMOS processing equipment. In a single layer, MPL is capable of creating all 5 2D-Bravais lattices. Furthermore, standard semiconductor processing steps can be used in a layer-by-layer approach to create fully three dimensional structures with any of the 14 3D-Bravais lattices. The unit cell basis is determined by the projection of the membrane pattern, with many degrees of freedom for defining functional inclusions. Here we demonstrate several unique structural motifs, and characterize 2D arrays of unit cells with split ring resonators in a silicon matrix. The structures exhibit strong polarization dependent resonances and, for properly oriented split ring resonators (SRRs), coupling to the magnetic field of a normally incident transverse electromagnetic wave, a response unique to 3D inclusions.
Three-dimensional modeling of heat transfer from slab floors. Final report
Bahnfleth, W.P.
1989-07-01
Earth-coupled heat-transfer processes have been recognized in recent years as a potential source of significant energy savings in both conventional and earth-sheltered designs, Because of the complexity of the building/soil/atmosphere interaction, however, important aspects of earth-coupled heat transfer are not well understood. There is a particular lack of three-dimensional foundation heat-loss data. In this study, a detailed three-dimensional finite-difference model of a slab floor was used to generate 93 annual simulations in parametric groups focusing on effects of size and shape, soil properties, boundary conditions, climate, insulation, and building shadow. These results indicate that soil thermal conductivity, ground surface conditions, foundation design, and floor shape/size are essential elements of a general change in heat-transfer rate.
Three-dimensional modeling and analysis of a high energy density Kelvin-Helmholtz experiment
Raman, K. S.; Hurricane, O. A.; Park, H.-S.; Remington, B. A.; Robey, H.; Smalyuk, V. A.; Drake, R. P.; Krauland, C. M.; Kuranz, C. C.; Hansen, J. F.; Harding, E. C.
2012-09-15
A recent series of experiments on the OMEGA laser provided the first controlled demonstration of the Kelvin-Helmholtz (KH) instability in a high-energy-density physics context [E. C. Harding et al., Phys. Rev. Lett. 103, 045005, (2009); O. A. Hurricane et al., Phys. Plasmas 16, 056305, (2009)]. We present 3D simulations which resolve previously reported discrepancies between those experiments and the 2D simulation used to design them. Our new simulations reveal a three-dimensional mechanism behind the low density 'bubble' structures which appeared in the experimental x-ray radiographs at late times but were completely absent in the 2D simulations. We also demonstrate that the three-dimensional expansion of the walls of the target is sufficient to explain the 20% overprediction by 2D simulation of the late-time growth of the KH rollups. The implications of these results for the design of future experiments are discussed.
Estimating Three-Dimensional Cloudy Radiative Transfer Effects from Time-Height Cross Sections
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Estimating Three-Dimensional Cloudy Radiative Transfer Effects from Time-Height Cross Sections C. Hannay and R. Pincus National Oceanic and Atmospheric Administration Climate Diagnostics Center Boulder, Colorado K. F. Evans Program in Atmospheric and Oceanic Sciences University of Colorado Boulder, Colorado Introduction Clouds in the atmosphere are finite in extent and variable in every direction and in time. Long data sets from ground-based profilers, such as lidars or cloud radars, could
Aizenberg, Joanna; Burgess, Ian B.; Mishchenko, Lidiya; Hatton, Benjamin; Loncar, Marko
2016-03-08
A three-dimensional porous photonic structure, whose internal pore surfaces can be provided with desired surface properties in a spatially selective manner with arbitrary patterns, and methods for making the same are described. When exposed to a fluid (e.g., via immersion or wicking), the fluid can selectively penetrate the regions of the structure with compatible surface properties. Broad applications, for example in security, encryption and document authentication, as well as in areas such as simple microfluidics and diagnostics, are anticipated.
Volume-scalable high-brightness three-dimensional visible light source
Subramania, Ganapathi; Fischer, Arthur J; Wang, George T; Li, Qiming
2014-02-18
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.
GEO3D - Three-Dimensional Computer Model of a Ground Source Heat Pump System
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
James Menart
2013-06-07
This file is the setup file for the computer program GEO3D. GEO3D is a computer program written by Jim Menart to simulate vertical wells in conjunction with a heat pump for ground source heat pump (GSHP) systems. This is a very detailed three-dimensional computer model. This program produces detailed heat transfer and temperature field information for a vertical GSHP system.
Redox Mediators that Promote Three-Dimensional Growth of Li2S on Carbon
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Current Collectors in Lithium-Sulfur Batteries - Joint Center for Energy Storage Research 21, 2015, Research Highlights Redox Mediators that Promote Three-Dimensional Growth of Li2S on Carbon Current Collectors in Lithium-Sulfur Batteries Controlling the electrodeposition of Li2S onto C using a redox mediator, BPI. With BPI, sulfur utilization improves in Li-S cells due to remote reduction of polysulfides to Li2S. Scientific Achievement Developed, from computation and experiment, redox
Three-dimensional heat transfer in a channel with a baffle in the entrance region
Guo, Z.; Anand, N.K.
1997-01-01
A numerical investigation of laminar forced convection was performed in a three-dimensional channel with a baffle in the entrance region. The top and bottom walls were subjected to a uniform heat flux heating condition, while the side walls were insulated. The numerical study was conducted using a finite volume approach, and the grid independence was established. Parametric runs were made for Reynolds numbers (Re) of 100--500; Prandtl numbers of 0.7 and 7.0; baffle heights (B{sub h}/D{sub h}) of 0.25, 0.50, and 0.75; and thermal conductivity ratios (K) of 10, 100, and 1,000. Three-dimensional effects in the flow field were confined to the neighborhood of the baffle, but three-dimensional effects in the temperature field were present in the entire channel. In general, separation length upstream of the baffle and recirculation length downstream of the baffle increased with an increase in the flow Reynolds number and baffle height. The spanwise averaged Nusselt number increased with an increase in the thermal conductivity of the wall.
Guo, Shimin Mei, Liquan
2014-08-15
Dust-ion-acoustic (DIA) rogue waves are investigated in a three-dimensional magnetized plasma containing nonthermal electrons featuring Tsallis distribution, both positive and negative ions, and immobile dust grains having both positive and negative charges. Via the reductive perturbation method, a (3?+?1)-dimensional nonlinear Schrödinger (NLS) equation is derived to govern the dynamics of the DIA wave packets. The modulation instability of DIA waves described by the (3?+?1)-dimensional NLS equation is investigated. By means of the similarity transformation and symbolic computation, both the first- and second-order rogue wave solutions of the (3?+?1)-dimensional NLS equation are constructed in terms of rational functions. Moreover, the dynamics properties and the effects of plasma parameters on the nonlinear structures of rogue waves are discussed in detail. The results could be useful for understanding the physical mechanism of rogue waves in laboratory experiments where pair-ion plasmas with electrons and dust grains can be found.
Simulations of Failure via Three-Dimensional Cracking in Fuel Cladding for Advanced Nuclear Fuels
Lu, Hongbing; Bukkapatnam, Satish; Harimkar, Sandip; Singh, Raman; Bardenhagen, Scott
2014-01-09
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.
SU-E-T-279: Realization of Three-Dimensional Conformal Dose Planning in Prostate Brachytherapy
Li, Z; Jiang, S; Yang, Z; Bai, H; Zhang, X
2014-06-01
Purpose: Successful clinical treatment in prostate brachytherapy is largely dependent on the effectiveness of pre-surgery dose planning. Conventional dose planning method could hardly arrive at a satisfy result. In this abstract, a three-dimensional conformal localized dose planning method is put forward to ensure the accuracy and effectiveness of pre-implantation dose planning. Methods: Using Monte Carlo method, the pre-calculated 3-D dose map for single source is obtained. As for multiple seeds dose distribution, the maps are combined linearly to acquire the 3-D distribution. The 3-D dose distribution is exhibited in the form of isodose surface together with reconstructed 3-D organs group real-timely. Then it is possible to observe the dose exposure to target volume and normal tissues intuitively, thus achieving maximum dose irradiation to treatment target and minimum healthy tissues damage. In addition, the exfoliation display of different isodose surfaces can be realized applying multi-values contour extraction algorithm based on voxels. The needles could be displayed in the system by tracking the position of the implanted seeds in real time to conduct block research in optimizing insertion trajectory. Results: This study extends dose planning from two-dimensional to three-dimensional, realizing the three-dimensional conformal irradiation, which could eliminate the limitations of 2-D images and two-dimensional dose planning. A software platform is developed using VC++ and Visualization Toolkit (VTK) to perform dose planning. The 3-D model reconstruction time is within three seconds (on a Intel Core i5 PC). Block research could be conducted to avoid inaccurate insertion into sensitive organs or internal obstructions. Experiments on eight prostate cancer cases prove that this study could make the dose planning results more reasonable. Conclusion: The three-dimensional conformal dose planning method could improve the rationality of dose planning by safely reducing the large target margin and avoiding dose dead zones for prostate cancer treatment. 1) National Natural Science Foundation of People's Republic of China (No. 51175373); 2) New Century Educational Talents Plan of Chinese Education Ministry (NCET-10-0625); 3) Scientific and Technological Major Project, Tianjin (No. 12ZCDZSY10600)
Porosity in millimeter-scale welds of stainless steel : three-dimensional characterization.
Aagesen, Larry K.; Madison, Jonathan D.
2012-05-01
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.
Binotti, M.; Zhu, G.; Gray, A.; Manzollini, G.
2012-04-01
An analytical approach, as an extension of one newly developed method -- First-principle OPTical Intercept Calculation (FirstOPTIC) -- is proposed to treat the geometrical impact of three-dimensional (3-D) effects on parabolic trough optical performance. The mathematical steps of this analytical approach are presented and implemented numerically as part of the suite of FirstOPTIC code. In addition, the new code has been carefully validated against ray-tracing simulation results and available numerical solutions. This new analytical approach to treating 3-D effects will facilitate further understanding and analysis of the optical performance of trough collectors as a function of incidence angle.
Photonic band gaps in three-dimensional network structures with short-range order
Liew, Seng Fatt; Noh, Heeso; Yang, Jin-Kyu; Schreck, Carl F.; Dufresne, Eric R.; O'Hern, Corey S.; Cao, Hui
2011-12-15
We present a systematic study of photonic band gaps (PBGs) in three-dimensional (3D) photonic amorphous structures (PASs) with short-range order. From calculations of the density of optical states (DOS) for PASs with different topologies, we find that tetrahedrally connected dielectric networks produce the largest isotropic PBGs. Local uniformity and tetrahedral order are essential to the formation of PBGs in PASs, in addition to short-range geometric order. This work demonstrates that it is possible to create broad, isotropic PBGs for vector light fields in 3D PASs without long-range order.
Three Dimensional Speckle Imaging Employing a Frequency-Locked Tunable Diode Laser
Cannon, Bret D.; Bernacki, Bruce E.; Schiffern, John T.; Mendoza, Albert
2015-09-01
We describe a high accuracy frequency stepping method for a tunable diode laser to improve a three dimensional (3D) imaging approach based upon interferometric speckle imaging. The approach, modeled after Takeda, exploits tuning an illumination laser in frequency as speckle interferograms of the object (specklegrams) are acquired at each frequency in a Michelson interferometer. The resulting 3D hypercube of specklegrams encode spatial information in the x-y plane of each image with laser tuning arrayed along its z-axis. We present laboratory data of before and after results showing enhanced 3D imaging resulting from precise laser frequency control.
Three-dimensional thermoelastic analysis of a Fort St. Vrain core support block
Butler, T.A.; Anderson, C.A.
1981-09-01
A thermoelastic stress analysis of a graphite core support block in the Fort St. Vrain High-Temperature Gas-Cooled Reactor is described. The support block is subjected to thermal stresses caused by a loss of forced circulation accident of the reactor system. Two- and three-dimensional finite element models of the core support block are analyzed using the ADINAT and ADINA codes, and results are given that verify the integrity of this structural component under the given accident condition. 10 refs., 39 figs.
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)
2014-03-03
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)
High energy gain in three-dimensional simulations of light sail acceleration
Sgattoni, A.; Sinigardi, S.; Macchi, A.
2014-08-25
The dynamics of radiation pressure acceleration in the relativistic light sail regime are analysed by means of large scale, three-dimensional (3D) particle-in-cell simulations. Differently to other mechanisms, the 3D dynamics leads to faster and higher energy gain than in 1D or 2D geometry. This effect is caused by the local decrease of the target density due to transverse expansion leading to a â€ślighter sail.â€ť However, the rarefaction of the target leads to an earlier transition to transparency limiting the energy gain. A transverse instability leads to a structured and inhomogeneous ion distribution.
Moon, Gun-Hee; Shin, Yongsoon; Choi, Daiwon; Arey, Bruce W.; Exarhos, Gregory J.; Wang, Chong M.; Choi, Wonyong; Liu, Jun
2013-01-01
We report a catalytic templating method to synthesize well-controlled, three-dimensional (3D) nano-architectures with graphene oxide sheets. The 3D composites are prepared via self-assembly of carbon, GO, and spherical alumina-coated silica (ACS) templates during a catalytic reaction porcess. By changing the GO content, we can systematically tune the architecture from layered composites to 3D hollow structures to microporous materials. The composites show a synergistic effect with significantly superior properties than either pure carbon or r-GO prepared with a significant enhancement to its capacitance at high current density.
Real-time, interactive animation of deformable two- and three-dimensional objects
Desbrun, Mathieu; Schroeder, Peter; Meyer, Mark; Barr, Alan H.
2003-06-03
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.
INGRID: a three-dimensional mesh generator for modeling nonlinear systems
Stillman, D.W.; Hallquist, J.O.
1985-07-01
INGRID generates complete input files for the codes DYNA3D, NIKE3D, FACET, and TOPAZ3D. Geometries are described primarily using index space concepts which came from the program INGEN. The ideas used in INGEN were reworked into a new method which is both simple and powerful. Interactive graphics in INGRID are patterned after TAURUS, a three-dimensional post-processor, and MAZE, a two-dimensional mesh generator. Much of the coding from MAZE is directly incorporated in INGRID.
Label-free three-dimensional imaging of cell nucleus using third-harmonic generation microscopy
Lin, Jian; Zheng, Wei; Wang, Zi; Huang, Zhiwei
2014-09-08
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.
Three-dimensional model and simulation of vacuum arcs under axial magnetic fields
Wang Lijun; Jia Shenli; Zhou Xin; Wang Haijing; Shi Zongqian
2012-01-15
In this paper, a three-dimensional (3d) magneto-hydro-dynamic (MHD) model of axial magnetic field vacuum arcs (AMFVAs) is established. Based on this model, AMFVAs are simulated and analyzed. Three-dimensional spatial distributions of many important plasma parameters and electric characteristics in AMFVAs can be obtained, such as ion number density, ion temperature, electron temperature, plasma pressure, current densities along different directions (x, y, and z), ion velocities along different directions, electric fields strength along different directions, and so on. Simulation results show that there exist significant spiral-shaped rotational phenomena in the AMFVAs, this kind of rotational phenomenon also can be verified by the many related experiments (AMFVAs photographs, especially for stronger AMF strength). For current simulation results of AMFVAs, the maximal rotational velocity at anode side is about 1100 m/s. Radial electric field is increased from arc center to arc edge; axial electric field is decreased from cathode side to anode side. Radial electric field at arc edge can be larger than axial electric field. Azimuthal electric field in most regions is much smaller than radial and axial electric field, but it can reach about 1.19 kV/m. Radial magnetic field is the smallest one compared with other components, it reaches to maximum value at the position near to anode, it can influence arc characteristics.
Image system for three dimensional, 360{degree}, time sequence surface mapping of moving objects
Lu, S.Y.
1998-12-22
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.
Controlled synthesis of hyper-branched inorganic nanocrystals withrich three-dimensional structures
Kanaras, Antonios G.; Sonnichsen, Carsten; Liu, Haitao; Alivisatos, A. Paul
2005-07-27
Studies of crystal growth kinetics are tightly integrated with advances in the creation of new nanoscale inorganic building blocks and their functional assemblies 1-11. Recent examples include the development of semiconductor nanorods which have potential uses in solar cells 12-17, and the discovery of a light driven process to create noble metal particles with sharp corners that can be used in plasmonics 18,19. In the course of studying basic crystal growth kinetics we developed a process for preparing branched semiconductor nanocrystals such as tetrapods and inorganic dendrimers of precisely controlled generation 20,21. Here we report the discovery of a crystal growth kinetics regime in which a new class of hyper-branched nanocrystals are formed. The shapes range from 'thorny balls', to tree-like ramified structures, to delicate 'spider net'-like particles. These intricate shapes depend crucially on a delicate balance of branching and extension. The multitudes of resulting shapes recall the diverse shapes of snowflakes 22.The three dimensional nature of the branch points here, however, lead to even more complex arrangements than the two dimensionally branched structures observed in ice. These hyper-branched particles not only extend the available three-dimensional shapes in nanoparticle synthesis ,but also provide a tool to study growth kinetics by carefully observing and modeling particle morphology.
Monodisperse alginate microgel formation in a three-dimensional microfluidic droplet generator
Lian, Meng; Collier, Pat; Doktycz, Mitchel John; Retterer, Scott T
2012-01-01
Droplet based microfluidic systems provide an ideal platform for partitioning and manipulating aqueous samples for analysis. Identifying stable operating conditions under which droplets are generated is challenging yet crucial for real-world applications. A novel three-dimensional microfluidic platform that facilitates the consistent generation and gelation of alginate-calcium hydrogel microbeads for microbial encapsulation, over a broad range of backing pressures, in the absence of surfactants, is described. The unique three-dimensional design of the fluidic network utilizes a height difference at the junction between the aqueous sample injection and organic carrier channels to induce droplet formation via a surface tension enhanced self-shearing mechanism. Combined within a flow-focusing geometry, under constant pressure control, this arrangement facilitates predictable generation of droplets over a much broader range of operating conditions than conventional two-dimensional systems. The impact of operating pressures and geometry on droplet gelation, aqueous and organic material flow rates, microbead size and bead generation frequency are described. The system presented provides a robust platform for encapsulating single microbes in complex mixtures into individual hydrogel beads, and provides the foundation for the development of a complete system for sorting and analyzing microbes at the single cell level.
Three-dimensional hydrodynamics of the deceleration stage in inertial confinement fusion
Weber, C. R. Clark, D. S.; Cook, A. W.; Eder, D. C.; Haan, S. W.; Hammel, B. A.; Hinkel, D. E.; Jones, O. S.; Marinak, M. M.; Milovich, J. L.; Patel, P. K.; Robey, H. F.; Salmonson, J. D.; Sepke, S. M.; Thomas, C. A.
2015-03-15
The deceleration stage of inertial confinement fusion implosions is modeled in detail using three-dimensional simulations designed to match experiments at the National Ignition Facility. In this final stage of the implosion, shocks rebound from the center of the capsule, forming the high-temperature, low-density hot spot and slowing the incoming fuel. The flow field that results from this process is highly three-dimensional and influences many aspects of the implosion. The interior of the capsule has high-velocity motion, but viscous effects limit the range of scales that develop. The bulk motion of the hot spot shows qualitative agreement with experimental velocity measurements, while the variance of the hot spot velocity would broaden the DT neutron spectrum, increasing the inferred temperature by 400–800?eV. Jets of ablator material are broken apart and redirected as they enter this dynamic hot spot. Deceleration stage simulations using two fundamentally different rad-hydro codes are compared and the flow field is found to be in good agreement.
Tewari, A.; Gokhale, A.M.; Gereman, R.M.
1999-10-08
Gravity affects microstructural evolution when a liquid phase is present during sintering. The effect of gravity on the three-dimensional coordination number distribution of tungsten grains in liquid phase sintered heavy alloy specimens is quantitatively characterized. A combination of montage serial sectioning, digital image processing, and unbiased stereological sampling procedures is used to estimate the coordination number distribution in three-dimensional microstructures. The microgravity environment decreases the mean coordination number. However, hardly any isolated grains are observed in the specimens, liquid phase sintered in a microgravity environment. The effect of microgravity on the coordination numbers mainly resides in its effect on the mean coordination number. In all specimens, there is a strong correlation between grain size and coordination number, which can be expressed as [D{sub c}/{bar D}]{sup 2} = C/C{sub 0} where C{sub 0} is the mean coordination number, {bar D} the global average size of the tungsten grains, and D{sub c} the average size of only those grains which have coordination number C.
Micrometer-scale fabrication of complex three dimensional lattice + basis structures in silicon
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Burckel, D. Bruce; Resnick, Paul J.; Finnegan, Patrick S.; Sinclair, Michael B.; Davids, Paul S.
2015-01-01
A complementary metal oxide semiconductor (CMOS) compatible version of membrane projection lithography (MPL) for fabrication of micrometer-scale three-dimensional structures is presented. The approach uses all inorganic materials and standard CMOS processing equipment. In a single layer, MPL is capable of creating all 5 2D-Bravais lattices. Furthermore, standard semiconductor processing steps can be used in a layer-by-layer approach to create fully three dimensional structures with any of the 14 3D-Bravais lattices. The unit cell basis is determined by the projection of the membrane pattern, with many degrees of freedom for defining functional inclusions. Here we demonstrate several unique structural motifs, andmore »characterize 2D arrays of unit cells with split ring resonators in a silicon matrix. The structures exhibit strong polarization dependent resonances and, for properly oriented split ring resonators (SRRs), coupling to the magnetic field of a normally incident transverse electromagnetic wave, a response unique to 3D inclusions.« less
Three-dimensional CTOA and constraint effects during stable tearing in a thin-sheet material
Dawicke, D.S.; Newman, J.C. Jr.; Bigelow, C.A.
1995-12-31
A small strain theory, three-dimensional elastic-plastic finite element analysis was used to simulate fracture in thin sheet 2024-T3 aluminum alloy in the T-L orientation. Both straight and tunneled cracks were modeled. The tunneled crack front shapes as a function of applied stress were obtained from the fracture surface of tested specimens. The stable crack growth behavior was measured at the specimen surface as a function of applied stress. The fracture simulation modeled the crack tunneling and extension as a function of applied stress. The results indicated that the global constrain factor, {alpha}{sub g}, initially dropped during stable crack growth. After peak applied stress was achieved, {alpha}{sub g}, initially dropped during stable crack growth. After peak applied stress was achieved, {alpha}{sub g}, began to increase slightly. The effect of crack front shape on {alpha}{sub g} was small, but the crack front shape did greatly influence the local constraint and through-thickness crack-tip opening angle (CTOA) behavior. The surface values of CTOA for the tunneled crack front model agreed well with experimental measurements, showing the same initial decrease from high values during the initial 3 mm of crack growth at the specimen`s surface. At the same time, the interior CTOA values increased from low angles. After the initial stable tearing region, the CTOA was constant through the thickness. The three-dimensional analysis appears to confirm the potential of CTOA as a two-dimensional fracture criterion.
Image system for three dimensional, 360 DEGREE, time sequence surface mapping of moving objects
Lu, Shin-Yee (Pleasanton, CA)
1998-01-01
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.
Three-dimensional analysis of eolian systems in Jurassic Wingate sandstone
Nation, M.J.; Blakey, R.C.
1989-03-01
Regional bounding surfaces in ancient eolian sequences aid in establishing lateral profiles not previously obtainable using standard stratigraphic methods. Correlation of detailed measured sections permits three-dimensional analysis of erg dynamics in the Jurassic Wingate Sandstone on the Colorado Plateau. Four periods of erg development marked by contrasting styles of eolian architecture are documented in the Salt Anticline region (in ascending stratigraphic order): (1) discontinuous sand sheets, isolated dunes, and aqueous environments; (2) large compound dunes with decreasing amounts of dune margin material; (3) compound dunes and draas alternating with locally thick sandsheet deposits; and (4) widespread dunes and draas prior to erosion by Kayenta fluvial systems. Regional bounding surface characteristics reflect different mechanisms for erg stabilization, including deflation to the water table, climate change, and negative net sand budget. Lateral reconstruction and correlation of erg sequences indicate significant intrabasinal paleogeographic and tectonic controls on eolian systems. Localities removed from the Salt Anticline region contain much larger compound draa deposits and lack extensive accumulations of sand-sheet material. Regional comparison of these characteristics suggests that the salt uplifts modified eolian processes within the Wingate depositional basin. Existence of additional geographic variations not associated with salt tectonism is indicated by local accumulations of noneolian deposits in northeastern Arizona. The use of regional bounding surfaces to construct lateral profiles is a powerful method to establish three-dimensional models of eolian systems. Analysis of erg dynamics in other ancient eolian formations is possible utilizing the criteria documented in the Wingate Sandstone.
Fathipour, Vala; Jang, Sung Jun; Nia, Iman Hassani; Mohseni, Hooman
2015-01-12
We present a quantitative study of the influence of three-dimensional geometry of the isolated electron–injection detectors on their characteristics. Significant improvements in the device performance are obtained as a result of scaling the injector diameter with respect to the trapping/absorbing layer diameters. Devices with about ten times smaller injector area with respect to the trapping/absorbing layer areas show more than an order of magnitude lower dark current, as well as an order of magnitude higher optical gain compared with devices of same size injector and trapping/absorbing layer areas. Devices with 10??m injector diameter and 30??m trapping/absorbing layer diameter show an optical gain of ?2000 at bias voltage of ?3?V with a cutoff wavelength of 1700?nm. Analytical expressions are derived for the electron-injection detector optical gain to qualitatively explain the significance of scaling the injector with respect to the absorber.
Measurement of the three-dimensional tip region flow field in an axial compressor
Stauter, R.C. )
1993-07-01
A two-color, five-beam LDV system has been configured to make simultaneous three-component velocity measurements of the flow field in a two-stage axial compressor model. The system has been used to make time-resolved measurements both between compressor blade rows and within the rotating blade passages in an axial compressor. The data show the nature and behavior of the complex, three-dimensional flow phenomena present in the tip region of a compressor as the convect downstream. In particular, the nature of the tip leakage vortex is apparent, being manifested by high blockage as well as the expected vortical motion. The data indicate that the radial flows associated with the tip leakage vortex begin to decrease while within the rotor passage, and that they temporarily increase aft of the passage.
Optical spectroscopy study of the three-dimensional Dirac semimetal ZrTe5
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Chen, R. Y.; Gu, G. D.; Zhang, S. J.; Schneeloch, J. A.; Zhang, C.; Li, Q.; Wang, N. L.
2015-08-05
Three-dimensional (3D) topological Dirac materials have been under intensive study recently. The layered compound ZrTe5 has been suggested to be one such material as a result of transport and angle-resolved photoemission spectroscopy experiments. Here, we perform infrared reflectivity measurements to investigate the underlying physics of this material. The derived optical conductivity increases linearly with frequency below normal interband transitions, which provides optical spectroscopic proof of a 3D Dirac semimetal. In addition, the plasma edge shifts dramatically to lower energy upon temperature cooling, which might be due to the shrinking of the lattice parameters. Additionally, an extremely sharp peak shows upmoreÂ Â» in the frequency-dependent optical conductivity, indicating the presence of a Van Hove singularity in the joint density of state.Â«Â less
Three dimensional winds: A maximum cross-correlation application to elastic lidar data
Buttler, W.T.
1996-05-01
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.
Whistler turbulence forward vs. inverse cascade. Three-dimensional particle-in-cell simulations
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Chang, Ouliang; Gary, S. Peter; Wang, Joseph
2015-02-12
In this study, we present the results of the first fully three-dimensional particle-in-cell simulations of decaying whistler turbulence in a magnetized, homogeneous, collisionless plasma in which both forward cascades to shorter wavelengths, and inverse cascades to longer wavelengths are allowed to proceed. For the electron beta Î˛e = 0.10 initial value considered here, the early-time rate of inverse cascade is very much smaller than the rate of forward cascade, so that at late times the fluctuation energy in the regime of the inverse cascade is much weaker than that in the forward cascade regime. Similarly, the wavevector anisotropy in themoreÂ Â» inverse cascade regime is much weaker than that in the forward cascade regime.Â«Â less
A BDDC Algorithm with Deluxe Scaling for Three-Dimensional H (curl) Problems
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Dohrmann, Clark R.; Widlund, Olof B.
2015-04-28
In our paper, we present and analyze a BDDC algorithm for a class of elliptic problems in the three-dimensional H(curl) space. Compared with existing results, our condition number estimate requires fewer assumptions and also involves two fewer powers of log(H/h), making it consistent with optimal estimates for other elliptic problems. Here, H/his the maximum of Hi/hi over all subdomains, where Hi and hi are the diameter and the smallest element diameter for the subdomain Î©i. The analysis makes use of two recent developments. The first is our new approach to averaging across the subdomain interfaces, while the second is amoreÂ Â» new technical tool that allows arguments involving trace classes to be avoided. Furthermore, numerical examples are presented to confirm the theory and demonstrate the importance of the new averaging approach in certain cases.Â«Â less
Elastodynamic behavior of the three dimensional layer-by-layer metamaterial structure
Aravantinos-Zafiris, N.; Sigalas, M. M.; Economou, E. N.
2014-10-07
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.
THREE-DIMENSIONAL DUST MAPPING REVEALS THAT ORION FORMS PART OF A LARGE RING OF DUST
Schlafly, E. F.; Rix, H.-W.; Martin, N. F.; Green, G.; Finkbeiner, D. P.; Burgett, W. S.; Chambers, K. C.; Kaiser, N.; Morgan, J. S.; Tonry, J. L.; Wainscoat, R. J.; Waters, C.; Draper, P. W.; Metcalfe, N.; Price, P. A.
2015-02-01
The Orion Molecular Complex is the nearest site of ongoing high-mass star formation, making it one of the most extensively studied molecular complexes in the Galaxy. We have developed a new technique for mapping the three-dimensional distribution of dust in the Galaxy using Pan-STARRS1 photometry. We isolate the dust at the distance to Orion using this technique, revealing a large (100 pc, 14° diameter), previously unrecognized ring of dust, which we term the ''Orion dust ring''. The ring includes Orion A and B, and is not coincident with current H? features. The circular morphology suggests formation as an ancient bubble in the interstellar medium, though we have not been able to conclusively identify the source of the bubble. This hint at the history of Orion may have important consequences for models of high-mass star formation and triggered star formation.
Large-angle illumination STEM: Toward three-dimensional atom-by-atom imaging
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Ishikawa, Ryo; Lupini, Andrew R.; Hinuma, Yoyo; Pennycook, Stephen
2014-11-26
To completely understand and control materials and their properties, it is of critical importance to determine their atomic structures in all three dimensions. Recent revolutionary advances in electron optics â€“ the inventions of geometric and chromatic aberration correctors as well as electron source monochromators â€“ have provided fertile ground for performing optical depth sectioning at atomic-scale dimensions. In this study we theoretically demonstrate the imaging of top/sub-surface atomic structures and identify the depth of single dopants, single vacancies and the other point defects within materials by large-angle illumination scanning transmission electron microscopy (LAI-STEM). The proposed method also allows us tomoreÂ Â» measure specimen properties such as thickness or three-dimensional surface morphology using observations from a single crystallographic orientation.Â«Â less
Three-dimensional carbon fibers and method and apparatus for their production
Muradov, Nazim Z.
2012-02-21
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.
Efficiency and accuracy aspects of a full-multigrid SIMPLE algorithm for three-dimensional flows
Lilek, Z.; Muzaferija, S.; Peric, M.
1997-01-01
This article reports on the analysis of efficiency and accuracy of a full-multigrid SIMPLE algorithm for three-dimensional flows using co-located grids and central difference discretization for both convective and diffusive fluxes. It is shown that the central differencing scheme--contrary to common belief--offers both good convergence properties and high accuracy, even at large Peclet numbers. Accurate solutions, with discretization errors below 0.5%, were obtained for lid-driven flows in a cubic cavity using grids with up to 128{sup 3} (nearly 2.1 million) control volumes. For a grid with 64{sup 3} (262,114) control volumes, solution can be obtained on a personal computer in 5--10 min. The computer code used for the calculations reported here is available from authors on request (free of charge).
Whistler turbulence forward vs. inverse cascade: Three-dimensional particle-in-cell simulations
Chang, Ouliang; Gary, S. Peter; Wang, Joseph
2015-02-12
In this study, we present the results of the first fully three-dimensional particle-in-cell simulations of decaying whistler turbulence in a magnetized, homogeneous, collisionless plasma in which both forward cascades to shorter wavelengths, and inverse cascades to longer wavelengths are allowed to proceed. For the electron beta ?_{e} = 0.10 initial value considered here, the early-time rate of inverse cascade is very much smaller than the rate of forward cascade, so that at late times the fluctuation energy in the regime of the inverse cascade is much weaker than that in the forward cascade regime. Similarly, the wavevector anisotropy in the inverse cascade regime is much weaker than that in the forward cascade regime.
Three-dimensional simulations of cellular non-premixed jet flames
Valaer, A.L.; Frouzakis, C.E.; Boulouchos, K.; Papas, P.; Tomboulides, A.G.
2010-04-15
The formation, dynamics and structure of cellular flames in circular non-premixed jets are examined with three-dimensional numerical simulations incorporating detailed descriptions of chemistry and transport. Similar to past experiments reported in the literature, CO{sub 2}-diluted hydrogen in diluted or pure oxygen co-flowing streams in the proximity of the extinction limit are considered. As in the experiments, several preferred cellular states are found to co-exist with the particular state realized depending on initial conditions as well as on the jet characteristics. The simulations provide additionally the temporal transitions to different stationary or rotating cellular flames, their detailed structure, and the dependence of the scaling of the realized number of cells with the vorticity thickness. (author)
Conversion of the Big Hill geological site characterization report to a three-dimensional model.
Stein, Joshua S.; Rautman, Christopher Arthur
2003-02-01
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.
2004-08-01
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.
Conversion of the Bryan Mound geological site characterization reports to a three-dimensional model.
Stein, Joshua S.; Rautman, Christopher Arthur
2005-04-01
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.
Zhan, Beibei; Liu, Changbing; Shi, Huaxia; Li, Chen; Wang, Lianhui [Key Laboratory for Organic Electronics and Information Displays (KLOEID), Nanjing University of Posts and Telecommunications, Nanjing 210023 (China); Huang, Wei, E-mail: iamxcdong@njtech.edu.cn, E-mail: iamwhuang@njtech.edu.cn; Dong, Xiaochen, E-mail: iamxcdong@njtech.edu.cn, E-mail: iamwhuang@njtech.edu.cn [Key Laboratory for Organic Electronics and Information Displays (KLOEID), Nanjing University of Posts and Telecommunications, Nanjing 210023 (China); Jiangsu-Singapore Joint Research Center for Organic/Bio-Electronics and Information Displays and Institute of Advanced Materials (IAM), Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816 (China)
2014-06-16
A facile strategy has been developed to synthesize sliver nanoparticles (Ag NPs) decorated three-dimensional graphene (3DG) through hydrothermal process. The AgNPs-3DG composites are directly fabricated into a free standing sensing electrode for electrochemical detection of hydrogen peroxide (H{sub 2}O{sub 2}) in phosphate buffered solutions. Various techniques equipments including scanning electron microscopy, X-ray diffraction, and Raman spectroscopy are used to characterize the morphology and structure of the as-prepared composite. The electrochemical experiments reveal the AgNPs-3DG based biosensor exhibits fast amperometric sensing, low detection limitation, wide linear responding range, and perfect selectivity for non-enzyme H{sub 2}O{sub 2} detection, indicating the well synergistic effect of Ag NPs high electrocatalytic activity and 3DG high conductivity and large surface area.
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. H.; et al
2006-01-01
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 spatialmoreÂ Â» 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.Â«Â less
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.
2008-01-01
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 ofmoreÂ Â» these thin films and the influence of different reaction parameters on the product are explained.Â«Â less
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Tourret, Damien; Clarke, Amy J.; Imhoff, Seth D.; Gibbs, Paul J.; Gibbs, John W.; Karma, Alain
2015-05-27
We present a three-dimensional extension of the multiscale dendritic needle network (DNN) model. This approach enables quantitative simulations of the unsteady dynamics of complex hierarchical networks in spatially extended dendritic arrays. We apply the model to directional solidification of Al-9.8 wt.%Si alloy and directly compare the model predictions with measurements from experiments with in situ x-ray imaging. The focus is on the dynamical selection of primary spacings over a range of growth velocities, and the influence of sample geometry on the selection of spacings. Simulation results show good agreement with experiments. The computationally efficient DNN model opens new avenues formoreÂ Â» investigating the dynamics of large dendritic arrays at scales relevant to solidification experiments and processes.Â«Â less
Three dimensional numerical simulations of the UPS-292 stratified charge engine
O'Rourke, P.J.; Amsden, A.A.
1987-01-01
The authors present and analyze three-dimensional calculations of the spray, mixing and combustion in the UPS-292 stratified charge engine for three different operating conditions, corresponding to overall air-fuel ratios between 22.4 and 61.0. The numerical calculations are performed with KIVA, a multidimensional arbitrary-mesh, finite-difference hydrodynamics program for internal combustion engine applications. The calculations use a mesh of 10,000 computational cells. Each operating condition is calculated from intake valve closure at 118/sup 0/ BTDC to 90/sup 0/ ATDC and requires approximately three hours of CRAY-XMP computer time. Combustion occurs primarily in the wake of the spark plug, and to include the effects of the spark plug on the flow field, we use a novel internal obstacle treatment. The methodology, in which internal obstacles are represented by computational particles, promises to be applicable to the calculation of the flows around intake and exhaust valves.
Method to planarize three-dimensional structures to enable conformal electrodes
Nikolic, Rebecca J; Conway, Adam M; Graff, Robert T; Reinhardt, Catherine; Voss, Lars F; Shao, Qinghui
2012-11-20
Methods for fabricating three-dimensional PIN structures having conformal electrodes are provided, as well as the structures themselves. The structures include a first layer and an array of pillars with cavity regions between the pillars. A first end of each pillar is in contact with the first layer. A segment is formed on the second end of each pillar. The cavity regions are filled with a fill material, which may be a functional material such as a neutron sensitive material. The fill material covers each segment. A portion of the fill material is etched back to produce an exposed portion of the segment. A first electrode is deposited onto the fill material and each exposed segment, thereby forming a conductive layer that provides a common contact to each the exposed segment. A second electrode is deposited onto the first layer.
Realizing three-dimensional artificial spin ice by stacking planar nano-arrays
Chern, Gia-Wei; Reichhardt, Charles; Nisoli, Cristiano
2014-01-06
Artificial spin ice is a frustrated magnetic two-dimensional nano-material, recently employed to study variety of tailor-designed unusual collective behaviours. Recently proposed extensions to three dimensions are based on self-assembly techniques and allow little control over geometry and disorder. We present a viable design for the realization of a three-dimensional artificial spin ice with the same level of precision and control allowed by lithographic nano-fabrication of the popular two-dimensional case. Our geometry is based on layering already available two-dimensional artificial spin ice and leads to an arrangement of ice-rule-frustrated units, which is topologically equivalent to that of the tetrahedra in a pyrochlore lattice. Consequently, we show, it exhibits a genuine ice phase and its excitations are, as in natural spin ice materials, magnetic monopoles interacting via Coulomb law.
Staff, Jan E.; Niebergal, Brian P.; Ouyed, Rachid; Pudritz, Ralph E.; Cai, Kai
2010-10-20
We perform state-of-the-art, three-dimensional, time-dependent simulations of magnetized disk winds, carried out to simulation scales of 60 AU, in order to confront optical Hubble Space Telescope observations of protostellar jets. We 'observe' the optical forbidden line emission produced by shocks within our simulated jets and compare these with actual observations. Our simulations reproduce the rich structure of time-varying jets, including jet rotation far from the source, an inner (up to 400 km s{sup -1}) and outer (less than 100 km s{sup -1}) component of the jet, and jet widths of up to 20 AU in agreement with observed jets. These simulations when compared with the data are able to constrain disk wind models. In particular, models featuring a disk magnetic field with a modest radial spatial variation across the disk are favored.
Method for the fabrication of three-dimensional microstructures by deep X-ray lithography
Sweatt, William C.; Christenson, Todd R.
2005-04-05
A method for the fabrication of three-dimensional microstructures by deep X-ray lithography (DXRL) comprises a masking process that uses a patterned mask with inclined mask holes and off-normal exposures with a DXRL beam aligned with the inclined mask holes. Microstructural features that are oriented in different directions can be obtained by using multiple off-normal exposures through additional mask holes having different orientations. Various methods can be used to block the non-aligned mask holes from the beam when using multiple exposures. A method for fabricating a precision 3D X-ray mask comprises forming an intermediate mask and a master mask on a common support membrane.
Simulating three-dimensional nonthermal high-energy photon emission in colliding-wind binaries
Reitberger, K.; Kissmann, R.; Reimer, A.; Reimer, O.
2014-07-01
Massive stars in binary systems have long been regarded as potential sources of high-energy ? rays. The emission is principally thought to arise in the region where the stellar winds collide and accelerate relativistic particles which subsequently emit ? rays. On the basis of a three-dimensional distribution function of high-energy particles in the wind collision region—as obtained by a numerical hydrodynamics and particle transport model—we present the computation of the three-dimensional nonthermal photon emission for a given line of sight. Anisotropic inverse Compton emission is modeled using the target radiation field of both stars. Photons from relativistic bremsstrahlung and neutral pion decay are computed on the basis of local wind plasma densities. We also consider photon-photon opacity effects due to the dense radiation fields of the stars. Results are shown for different stellar separations of a given binary system comprising of a B star and a Wolf-Rayet star. The influence of orbital orientation with respect to the line of sight is also studied by using different orbital viewing angles. For the chosen electron-proton injection ratio of 10{sup –2}, we present the ensuing photon emission in terms of two-dimensional projections maps, spectral energy distributions, and integrated photon flux values in various energy bands. Here, we find a transition from hadron-dominated to lepton-dominated high-energy emission with increasing stellar separations. In addition, we confirm findings from previous analytic modeling that the spectral energy distribution varies significantly with orbital orientation.
Biffle, J.H.
1993-02-01
JAC3D is a three-dimensional finite element program designed to solve quasi-static nonlinear mechanics problems. A set of continuum equations describes the nonlinear mechanics involving large rotation and strain. A nonlinear conjugate gradient method is used to solve the equation. The method is implemented in a three-dimensional setting with various methods for accelerating convergence. Sliding interface logic is also implemented. An eight-node Lagrangian uniform strain element is used with hourglass stiffness to control the zero-energy modes. This report documents the elastic and isothermal elastic-plastic material model. Other material models, documented elsewhere, are also available. The program is vectorized for efficient performance on Cray computers. Sample problems described are the bending of a thin beam, the rotation of a unit cube, and the pressurization and thermal loading of a hollow sphere.
Felipe, T.; Khomenko, E.; Collados, M.
2010-08-10
Waves observed in the photosphere and chromosphere of sunspots show complex dynamics and spatial patterns. The interpretation of high-resolution sunspot wave observations requires modeling of three-dimensional (3D) nonlinear wave propagation and mode transformation in the sunspot upper layers in realistic spot model atmospheres. Here, we present the first results of such modeling. We have developed a 3D nonlinear numerical code specially designed to calculate the response of magnetic structures in equilibrium to an arbitrary perturbation. The code solves the 3D nonlinear MHD equations for perturbations; it is stabilized by hyper-diffusivity terms and is fully parallelized. The robustness of the code is demonstrated by a number of standard tests. We analyze several simulations of a sunspot perturbed by pulses of different periods at a subphotospheric level, from short periods, introduced for academic purposes, to longer and realistic periods of 3 and 5 minutes. We present a detailed description of the 3D mode transformation in a non-trivial sunspot-like magnetic field configuration, including the conversion between fast and slow magneto-acoustic waves and the Alfven wave, by calculation of the wave energy fluxes. Our main findings are as follows: (1) the conversion from acoustic to the Alfven mode is only observed if the driving pulse is located out of the sunspot axis, but this conversion is energetically inefficient; (2) as a consequence of the cutoff effects and refraction of the fast magneto-acoustic mode, the energy of the evanescent waves with periods around 5 minutes remains almost completely below the level {beta} = 1; (3) waves with frequencies above the cutoff propagate field aligned to the chromosphere and their power becomes dominating over that of evanescent 5 minute oscillations, in agreement with observations.
Three-dimensional analysis of AP600 standard plant shield building roof
Greimann, L.; Fanous, F.; Safar, S.; Khalil, A.; Bluhm, D.
1999-06-01
The AP600 passive containment vessel is surrounded by a concrete cylindrical shell covered with a truncated conical roof. This roof supports the passive containment cooling system (PCS) annular tank, shield plate and other nonstructural attachments. When the shield building is subjected to different loading combinations as defined in the Standard Review Plan (SRP), some of the sections in the shield building could experience forces in excess of their design values. This report summarized the three-dimensional finite element analysis that was conducted to review the adequacy of the proposed Westinghouse shield building design. The ANSYS finite element software was utilized to analyze the Shield Building Roof (SBR) under dead, snow, wind, thermal and seismic loadings. A three-dimensional model that included a portion of the shield building cylindrical shell, the conical roof and its attachments, the eccentricities at the cone-cylinder connection and at the compression ring and the PCS tank was developed. Mesh sensitivity studies were conducted to select appropriate element size in the cylinder, cone, near air intakes and in the vicinity of the eccentricities. Also, a study was carried out to correctly idealize the water-structure interaction in the PCS tank. Response spectrum analysis was used to calculate the internal forces at different sections in the SBR under Safe Shutdown Earthquake (SSE). Forty-nine structural modes and twenty sloshing modes were used. Two horizontal components of the SSE together with a vertical component were used. Modal stress resultants were combined taking into account the effects of closely spaced modes. The three earthquake directions were combined by the Square Root of the Sum Squares method. Two load combinations were studied. The load combination that included dead, snow, fluid, thermal and seismic loads was selected to be the most critical. Interaction diagrams for critical sections were developed and used to check the design adequacy. The results demonstrated that provided area of steal on each face of several sections of the AP600 SBR was inadequate. This was also noticed when comparing the total provided area of steel per section, i.e., the area of steel on both faces. The discrepancy between Westinghouse results and these reported herein could have resulted from the different finite element mesh sizes and the assumption used in Westinghouse design.
Evolution of flux ropes in the magnetotail: A three-dimensional global hybrid simulation
Lu, S.; Lin, Y.; Wang, X. Y.; Lu, Q. M. Huang, C.; Wu, M. Y.; Wang, S.; Wang, R. S.
2015-05-15
Flux ropes in the Earth's magnetotail are widely believed to play a crucial role in energy transport during substorms and the generation of energetic particles. Previous kinetic simulations are limited to the local-scale regime, and thus cannot be used to study the structure associated with the geomagnetic field and the global-scale evolution of the flux ropes. Here, the evolution of flux ropes in the magnetotail under a steady southward interplanetary magnetic field are studied with a newly developed three-dimensional global hybrid simulation model for dynamics ranging from the ion Larmor radius to the global convection time scales. Magnetic reconnection with multiple X-lines is found to take place in the near-tail current sheet at geocentric solar magnetospheric distances x=?30R{sub E}??15R{sub E} around the equatorial plane (z=0). The magnetotail reconnection layer is turbulent, with a nonuniform structure and unsteady evolution, and exhibits properties of typical collisionless fast reconnection with the Hall effect. A number of small-scale flux ropes are generated through the multiple X-line reconnection. The diameter of the flux ropes is several R{sub E}, and the spatial scale of the flux ropes in the dawn-dusk direction is on the order of several R{sub E} and does not extend across the entire section of the magnetotail, contrary to previous models and MHD simulation results and showing the importance of the three-dimensional effects. The nonuniform and unsteady multiple X-line reconnection with particle kinetic effects leads to various kinds of flux rope evolution: The small-scale flux ropes propagate earthward or tailward after formation, and eventually merge into the near-Earth region or the mid-/distant-tail plasmoid, respectively. During the propagation, some of the flux ropes can be tilted in the geocentric solar magnetospheric (x,y) plane with respect to the y (dawn-dusk) axis. Coalescence between flux ropes is also observed. At the same time, the evolution of the flux ropes in the multiple X-line reconnection layer can also lead to the acceleration and heating of ions.
Convection Heat Transfer in Three-Dimensional Turbulent Separated/Reattached Flow
Bassem F. Armaly
2007-10-31
The measurements and the simulation of convective heat transfer in separated flow have been a challenge to researchers for many years. Measurements have been limited to two-dimensional flow and simulations failed to predict accurately turbulent heat transfer in the separated and reattached flow region (prediction are higher than measurements by more than 50%). A coordinated experimental and numerical effort has been initiated under this grant for examining the momentum and thermal transport in three-dimensional separated and reattached flow in an effort to provide new measurements that can be used for benchmarking and for improving the simulation capabilities of 3-D convection in separated/reattached flow regime. High-resolution and non-invasive measurements techniques are developed and employed in this study to quantify the magnitude and the behavior of the three velocity components and the resulting convective heat transfer. In addition, simulation capabilities are developed and employed for improving the simulation of 3-D convective separated/reattached flow. Such basic measurements and simulation capabilities are needed for improving the design and performance evaluation of complex (3-D) heat exchanging equipment. Three-dimensional (3-D) convective air flow adjacent to backward-facing step in rectangular channel is selected for the experimental component of this study. This geometry is simple but it exhibits all the complexities that appear in any other separated/reattached flow, thus making the results generated in this study applicable to any other separated and reattached flow. Boundary conditions, inflow, outflow, and wall thermal treatment in this geometry can be well measured and controlled. The geometry can be constructed with optical access for non-intrusive measurements of the flow and thermal fields. A three-component laser Doppler velocimeter (LDV) is employed to measure simultaneously the three-velocity components and their turbulent fluctuations. Infrared thermography is utilized to measure the wall temperature and that information is used to determine the local convective heat transfer coefficient. FLUENT – CFD code is used as the platform in the simulation effort and User Defined Functions are developed for incorporating advanced turbulence models into this simulation code. Predictions of 3-D turbulent convection in separated flow, using the developed simulation capabilities under this grant, compared well with measured results. Results from the above research can be found in the seventeen refereed journal articles, and thirteen refereed publications and presentations in conference proceedings that have been published by the PI during the this grant period. The research effort is still going on and several publications are being prepared for reporting recent results.
Covalently bonded three-dimensional carbon nanotube solids via boron induced nanojunctions
Sumpter, Bobby G; Meunier, Vincent; Terrones Maldonado, Humberto; Terrones Maldonado, Mauricio; Ajayan, Pullikel M; Hashim, Daniel; Romo Herrera, Jose M; Cullen, David; Munoz-Sandoval, Emilio; Smith, David J; Vajtai, Robert; Roy, Ajit K; Ganguli, Sabyasachi; Kelkhoff, Doug; Suttle, Joesph; Lezzi, Peter; Hahm, Gwan; Narayanan, Narayanan
2012-01-01
The establishment of covalent junctions between carbon nanotubes (CNTs) and the modification of their straight tubular morphology are two strategies needed to successfully synthesize nanotube-based three-dimensional (3D) frameworks exhibiting superior material properties. Engineering such 3D structures in scalable synthetic processes still remains a challenge. This work pioneers the bulk synthesis of 3D macroscale nanotube elastic solids directly via a boron-doping strategy during chemical vapor deposition, which influences the formation of atomic-scale elbow junctions and nanotube covalent interconnections. Detailed elemental analysis revealed that the elbow junctions are preferred sites for excess boron atoms, indicating the role of boron and curvature in the junction formation mechanism, in agreement with our first principle theoretical calculations. Exploiting this material s ultra-light weight, super-hydrophobicity, high porosity, thermal stability, and mechanical flexibility, the strongly oleophilic sponge-like solids are demonstrated as unique reusable sorbent scaffolds able to efficiently remove oil from contaminated seawater even after repeated use.
Burke, Micheal 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.
2015-01-01
The authors report on the structural and electrical properties of TiN/Al{sub 2}O{sub 3}/TiN metalâ€“insulatorâ€“metal (MIM) capacitor structures in submicron three-dimensional (3D) trench geometries with an aspect ratio of âĽ30. 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 250â€‰Â°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/ÎĽm{sup 2} and quality factors >65 at low frequency (200â€‰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.
Defect propagation in one-, two-, and three-dimensional compounds doped by magnetic atoms
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Furrer, A.; Podlesnyak, A.; KrĂ¤mer, K. W.; StrĂ¤ssle, Th.
2014-10-29
Inelastic neutron scattering experiments were performed to study manganese(II) dimer excitations in the diluted one-, two-, and three-dimensional compounds CsMnxMg1-xBr3, K2MnxZn1-xF4, and KMnxZn1-xF3 (xâ‰¤0.10), respectively. The transitions from the ground-state singlet to the excited triplet, split into a doublet and a singlet due to the single-ion anisotropy, exhibit remarkable fine structures. These unusual features are attributed to local structural inhomogeneities induced by the dopant Mn atoms which act like lattice defects. Statistical models support the theoretically predicted decay of atomic displacements according to 1/r2, 1/r, and constant (for three-, two-, and one-dimensional compounds, respectively) where r denotes the distance ofmoreÂ Â» the displaced atoms from the defect. In conclusion, the observed fine structures allow a direct determination of the local exchange interactions J, and the local intradimer distances R can be derived through the linear law dJ/dR.Â«Â less
Electron and ion heating by whistler turbulence: Three-dimensional particle-in-cell simulations
Hughes, R. Scott; Gary, S. Peter; Wang, Joseph
2014-12-17
Three-dimensional particle-in-cell simulations of decaying whistler turbulence are carried out on a collisionless, homogeneous, magnetized, electron-ion plasma model. In addition, the simulations use an initial ensemble of relatively long wavelength whistler modes with a broad range of initial propagation directions with an initial electron beta ?_{e} = 0.05. The computations follow the temporal evolution of the fluctuations as they cascade into broadband turbulent spectra at shorter wavelengths. Three simulations correspond to successively larger simulation boxes and successively longer wavelengths of the initial fluctuations. The computations confirm previous results showing electron heating is preferentially parallel to the background magnetic field B_{o}, and ion heating is preferentially perpendicular to B_{o}. The new results here are that larger simulation boxes and longer initial whistler wavelengths yield weaker overall dissipation, consistent with linear dispersion theory predictions of decreased damping, stronger ion heating, consistent with a stronger ion Landau resonance, and weaker electron heating.
Efficient multilevel finite-element approach to three-dimensional phase-change problems
Lee, R.T.; Chiou, W.Y.
1997-01-01
A finite-element (FE) formulation suitable for a multigrid algorithm in solving three-dimensional phase-change problems is described. This formulation is based on the averaged specific heat model. The algorithm has been proved to be very useful for large problems where the computational complexity can be reduced from O(n{sup 3}) to O(n ln n) with high storage efficiency in a personal computer. To evaluate the accuracy of the present algorithm, the numerical results for larger slender ratio are compared with previous analytical solutions. Results show that the numerical solutions at the symmetric surface of the long axis are in very good agreement with the two-dimensional exact solutions for slender ratio = 5. The magnitudes of time steps and freezing-temperature intervals are insensitive to the maximal and average absolute errors when the time step is less than 0.01 s. Consequently, a larger time step can be used to save computing time and retain the same order of accuracy. This algorithm is also available for pure metals and alloys that exhibit a very large or small (or zero) freezing-temperature interval.
Impacts of rotation on three-dimensional hydrodynamics of core-collapse supernovae
Nakamura, Ko; Kuroda, Takami; Kotake, Kei [Division of Theoretical Astronomy, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Takiwaki, Tomoya [Center for Computational Astrophysics, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
2014-09-20
We perform a series of simplified numerical experiments to explore how rotation impacts the three-dimensional (3D) hydrodynamics of core-collapse supernovae. For our systematic study, we employ a light-bulb scheme to trigger explosions and a three-flavor neutrino leakage scheme to treat deleptonization effects and neutrino losses from the proto-neutron-star interior. Using a 15 M {sub ?} progenitor, we compute 30 models in 3D with a wide variety of initial angular momentum and light-bulb neutrino luminosity. We find that the rotation can help the onset of neutrino-driven explosions for the models in which the initial angular momentum is matched to that obtained in recent stellar evolutionary calculations (?0.3-3 rad s{sup –1} at the center). For the models with larger initial angular momentum, the shock surface deforms to be more oblate due to larger centrifugal force. This not only makes the gain region more concentrated around the equatorial plane, but also makes the mass larger in the gain region. As a result, buoyant bubbles tend to be coherently formed and rise in the equatorial region, which pushes the revived shock toward ever larger radii until a global explosion is triggered. We find that these are the main reasons that the preferred direction of the explosion in 3D rotating models is often perpendicular to the spin axis, which is in sharp contrast to the polar explosions around the axis that were obtained in previous two-dimensional simulations.
Lin, Yu; Huang, Chong; Irwin, Daniel; He, Lian; Shang, Yu; Yu, Guoqiang
2014-03-24
This study extended our recently developed noncontact diffuse correlation spectroscopy flowmetry system into noncontact diffuse correlation tomography (ncDCT) for three-dimensional (3-D) flow imaging of deep tissue. A linear array of 15 photodetectors and two laser sources connected to a mobile lens-focusing system enabled automatic and noncontact scanning of flow in a region of interest. These boundary measurements were combined with a finite element framework for DCT image reconstruction implemented into an existing software package. This technique was tested in computer simulations and using a tissue-like phantom with anomaly flow contrast design. The cylindrical tube-shaped anomaly was clearly reconstructed in both simulation and phantom. Recovered and assigned flow contrast changes in anomaly were found to be highly correlated: regression slopeâ€‰=â€‰1.00, R{sup 2}â€‰=â€‰1.00, and pâ€‰<â€‰10{sup â’5} in simulation and regression slopeâ€‰â‰Ąâ€‰0.97, R{sup 2}â€‰â‰Ąâ€‰0.96, and pâ€‰<â€‰10{sup â’3} in phantom. These results exhibit promise of our ncDCT technique for 3-D imaging of deep tissue blood flow heterogeneities.
Fernandez-Gonzalez, Rodrigo; Jones, Arthur; Garcia-Rodriguez, Enrique; Yuan Chen, Ping; Idica, Adam; Lockett, Stephen J.; Barcellos-Hoff, Mary Helen; Ortiz-de-Solorzano, Carlos
2002-04-25
We present a new system for simultaneous morphological and molecular analysis of thick tissue samples. The system is composed of a computer assisted microscope and a JAVA-based image display, analysis and visualization program that allows acquisition, annotation, meaningful storage, three-dimensional reconstruction and analysis of structures of interest in thick sectioned tissue specimens. We describe the system in detail and illustrate its use by imaging, reconstructing and analyzing two complete tissue blocks which were differently processed and stained. One block was obtained from a ductal carcinoma in situ (DCIS) lumpectomy specimen and stained alternatively with Hematoxilyn and Eosin (H&E), and with a counterstain and fluorescence in situ hybridization (FISH) to the ERB-B2 gene. The second block contained a fully sectioned mammary gland of a mouse, stained for Histology with H&E. We show how the system greatly reduces the amount of interaction required for the acquisition and analysis and is therefore suitable for studies that require morphologically driven, wide scale (e.g., whole gland) analysis of complex tissue samples or cultures.
Puthen-Veettil, B. Patterson, R.; König, D.; Conibeer, G.; Green, M. A.
2014-10-28
Efficient iso-entropic energy filtering of electronic waves can be realized through nanostructures with three dimensional confinement, such as quantum dot resonant tunneling structures. Large-area deployment of such structures is useful for energy selective contacts but such configuration is susceptible to structural disorders. In this work, the transport properties of quantum-dot-based wide-area resonant tunneling structures, subject to realistic disorder mechanisms, are studied. Positional variations of the quantum dots are shown to reduce the resonant transmission peaks while size variations in the device are shown to reduce as well as broaden the peaks. Increased quantum dot size distribution also results in a peak shift to lower energy which is attributed to large dots dominating transmission. A decrease in barrier thickness reduces the relative peak height while the overall transmission increases dramatically due to lower “series resistance.” While any shift away from ideality can be intuitively expected to reduce the resonance peak, quantification allows better understanding of the tolerances required for fabricating structures based on resonant tunneling phenomena/.
Lee, Heung-Rae
1997-01-01
A three-dimensional image reconstruction method comprises treating the object of interest as a group of elements with a size that is determined by the resolution of the projection data, e.g., as determined by the size of each pixel. One of the projections is used as a reference projection. A fictitious object is arbitrarily defined that is constrained by such reference projection. The method modifies the known structure of the fictitious object by comparing and optimizing its four projections to those of the unknown structure of the real object and continues to iterate until the optimization is limited by the residual sum of background noise. The method is composed of several sub-processes that acquire four projections from the real data and the fictitious object: generate an arbitrary distribution to define the fictitious object, optimize the four projections, generate a new distribution for the fictitious object, and enhance the reconstructed image. The sub-process for the acquisition of the four projections from the input real data is simply the function of acquiring the four projections from the data of the transmitted intensity. The transmitted intensity represents the density distribution, that is, the distribution of absorption coefficients through the object.
THREE-DIMENSIONAL NUMERICAL SIMULATIONS OF FAST-TO-ALFVEN CONVERSION IN SUNSPOTS
Felipe, T.
2012-10-20
The conversion of fast waves to the Alfven mode in a realistic sunspot atmosphere is studied through three-dimensional numerical simulations. An upward propagating fast acoustic wave is excited in the high-{beta} region of the model. The new wave modes generated at the conversion layer are analyzed from the projections of the velocity and magnetic field in their characteristic directions, and the computation of their wave energy and fluxes. The analysis reveals that the maximum efficiency of the conversion to the slow mode is obtained for inclinations of 25 Degree-Sign and low azimuths, while the Alfven wave conversions peak at high inclinations and azimuths between 50 Degree-Sign and 120 Degree-Sign . Downward propagating Alfven waves appear at the regions of the sunspot where the orientation of the magnetic field is in the direction opposite to the wave propagation, since at these locations the Alfven wave couples better with the downgoing fast magnetic wave which is reflected due to the gradients of the Alfven speed. The simulations show that the Alfven energy at the chromosphere is comparable to the acoustic energy of the slow mode, being even higher at high inclined magnetic fields.
Touqan, Abdul Razzaq
2008-07-08
Present methods of analysis and mathematical modeling contain so many assumptions that separate them from reality and thus represent a defect in design which makes it difficult to analyze reasons of failure. Three dimensional (3D) modeling is so superior to 1D or 2D modeling, static analysis deviates from the true nature of earthquake load which is 'a dynamic punch', and conflicting assumptions exist between structural engineers (who assume flexible structures on rigid block foundations) and geotechnical engineers (who assume flexible foundations supporting rigid structures). Thus a 3D dynamic soil-structure interaction is a step that removes many of the assumptions and thus clears reality to a greater extent. However such a model cannot be analytically analyzed. We need to anatomize and analogize it. The paper will represent a conceptual (analogical) 1D model for soil structure interaction and clarifies it by comparing its outcome with 3D dynamic soil-structure finite element analysis of two structures. The aim is to focus on how to calculate the period of the structure and to investigate effect of variation of stiffness on soil-structure interaction.
Three-dimensional hybrid simulation study of anisotropic turbulence in the proton kinetic regime
Vasquez, Bernard J.; Markovskii, Sergei A.; Chandran, Benjamin D. G. E-mail: sergei.markovskii@unh.edu
2014-06-20
Three-dimensional numerical hybrid simulations with particle protons and quasi-neutralizing fluid electrons are conducted for a freely decaying turbulence that is anisotropic with respect to the background magnetic field. The turbulence evolution is determined by both the combined root-mean-square (rms) amplitude for fluctuating proton bulk velocity and magnetic field and by the ratio of perpendicular to parallel wavenumbers. This kind of relationship had been considered in the past with regard to interplanetary turbulence. The fluctuations nonlinearly evolve to a turbulent phase whose net wave vector anisotropy is usually more perpendicular than the initial one, irrespective of the initial ratio of perpendicular to parallel wavenumbers. Self-similar anisotropy evolution is found as a function of the rms amplitude and parallel wavenumber. Proton heating rates in the turbulent phase vary strongly with the rms amplitude but only weakly with the initial wave vector anisotropy. Even in the limit where wave vectors are confined to the plane perpendicular to the background magnetic field, the heating rate remains close to the corresponding case with finite parallel wave vector components. Simulation results obtained as a function of proton plasma to background magnetic pressure ratio Î˛ {sub p} in the range 0.1-0.5 show that the wave vector anisotropy also weakly depends on Î˛ {sub p}.
Lee, H.R.
1997-11-18
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.
Current singularities in line-tied three-dimensional magnetic fields
Craig, I. J. D.; Pontin, D. I. E-mail: dpontin@maths.dundee.ac.uk
2014-06-20
This paper considers the current distributions that derive from finite amplitude perturbations of line-tied magnetic fields comprising hyperbolic field structures. The initial equilibrium on which we principally focus is a planar magnetic X-point threaded by a uniform axial field. This field is line-tied on all surfaces but subject to three-dimensional (3D) disturbances that alter the initial topology. Results of ideal relaxation simulations are presented which illustrate how intense current structures form that can be related, through the influence of line-tying, to the quasi-separatrix layers (QSLs) of the initial configuration. It is demonstrated that the location within the QSL that attracts the current, and its scaling properties, are strongly dependent on the relative dimensions of the QSL with respect to the line-tied boundaries. These results are contrasted with the behavior of a line-tied 3D field containing an isolated null point. In this case, it is found that the dominant current always forms at the null, but that the collapse is inhibited when the null is closer to a line-tied boundary.
Three-dimensional finite element impact analysis of a nuclear waste truck cask
Miller, J.D.
1985-05-01
A three-dimensional finite element impact analysis of a hypothetical accident event for the preliminary design of a shipping cask to be used to transport radioactive waste by standard tractor-semitrailer truck is presented. The dynamic structural analysis code DYNA3D, run on Sandia's Cray-1 computer, was used to calculate the effects of the closure-end of the cask impacting a rigid, frictionless surface on an edge of its external impact limiter after a 30-foot fall. The center of gravity of the 304 stainless steel and depleted uranium cask was assumed to be directly above the impact point. An elastic-plastic material constitutive model was used to calculate the nonlinear response of the cask components to the transient loading. Results from the calculations show the cask sustained large localized deformations. However, these were almost entirely confined to the impact limiters built into the cask. The closure sections were determined to remain intact and leakage would not be expected after the event. Interactive color computer graphics were used throughout the analysis, proving to be extremely helpful for generation and verification of the geometry and boundary conditions of the finite element model and for interpretation of the analysis results. 12 refs., 29 figs., 4 tabs.
The influence of intense electric fields on three-dimensional asymmetric magnetic reconnection
Pritchett, P. L.
2013-06-15
A three-dimensional particle-in-cell simulation of magnetic reconnection in an asymmetric configuration without a guide field and with temperature ratio T{sub i}/T{sub e}>1 demonstrates that intense perpendicular electric fields are produced on the low-density side of the current layer where there is a strong gradient in the plasma density. The simulation shows that the 3-D reconnection rate is unaffected by these intense electric fields, that the electron current layer near the X line remains coherent and does not break up, but that localized regions of strong energy dissipation exist along the low-density separatrices. Near the X line the dominant term in the generalized Ohm's law for the reconnection electric field remains the off-diagonal electron pressure gradient â‚P{sub exy}/â‚x. On the low-beta separatrix, however, the anomalous drag â’<Î´nÎ´E{sub y}>/
Myers, C. E.; Belova, E. V.; Brown, M. R.; Gray, T.; Cothran, C. D.; Schaffer, M. J.
2011-11-15
Recent counter-helicity spheromak merging experiments in the Swarthmore Spheromak Experiment (SSX) have produced a novel compact torus (CT) with unusual features. These include a persistent antisymmetric toroidal magnetic field profile and a slow, nonlinear emergence of the n = 1 tilt mode. Experimental measurements are inconclusive as to whether this unique CT is a fully merged field-reversed configuration (FRC) with strong toroidal field or a partially merged ''doublet CT'' configuration with both spheromak- and FRC-like characteristics. In this paper, the SSX merging process is studied in detail using three-dimensional resistive MHD simulations from the Hybrid Magnetohydrodynamics (HYM) code. These simulations show that merging plasmas in the SSX parameter regime only partially reconnect, leaving behind a doublet CT rather than an FRC. Through direct comparisons, we show that the magnetic structure in the simulations is highly consistent with the SSX experimental observations. We also find that the n = 1 tilt mode begins as a fast growing linear mode that evolves into a slower-growing nonlinear mode before being detected experimentally. A simulation parameter scan over resistivity, viscosity, and line-tying shows that these parameters can strongly affect the behavior of both the merging process and the tilt mode. In fact, merging in certain parameter regimes is found to produce a toroidal-field-free FRC rather than a doublet CT.
Application of a three-dimensional, prognostic model to Mexico City air quality studies
Williams, M.D.; Porch, W.M.
1991-01-01
Los Alamos National Laboratory and Instituto Mexicano del Petroleo have embarked on a joint study of options for improving air quality in Mexico City. One of the first steps in the process is to develop an understanding of the existing air quality situation. In this context we have begun by modifying a three-dimensional, prognostic, higher order turbulence model for atmospheric circulation (HOTMAC) to threat domains which include an urbanized area. This sophisticated meteorological model is required because of the complexity of the terrain and the relative paucity of meteorological data. The basic model (HOTMAC) was modified to include an urban canopy and urban heat sources. HOTMAC has been used to drive a Monte-Carlo kernel dispersion code (RAPTAD). RAPTAD was used to model the flow of carbon monoxide and sulfur dioxide, and the results have been compared to measurements. In addition the modeled wind fields which are based on upper-level winds from the airport are compared to the measured low-level winds. Also, a four year history of temperature structure obtained from the rawinsode at the airport has been related to mixing parameters and less reactive pollutant measurements (such as carbon monoxide). 10 refs., 15 figs.
Electron and ion heating by whistler turbulence: Three-dimensional particle-in-cell simulations
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Hughes, R. Scott; Gary, S. Peter; Wang, Joseph
2014-12-17
Three-dimensional particle-in-cell simulations of decaying whistler turbulence are carried out on a collisionless, homogeneous, magnetized, electron-ion plasma model. In addition, the simulations use an initial ensemble of relatively long wavelength whistler modes with a broad range of initial propagation directions with an initial electron beta Î˛e = 0.05. The computations follow the temporal evolution of the fluctuations as they cascade into broadband turbulent spectra at shorter wavelengths. Three simulations correspond to successively larger simulation boxes and successively longer wavelengths of the initial fluctuations. The computations confirm previous results showing electron heating is preferentially parallel to the background magnetic field Bo,moreÂ Â» and ion heating is preferentially perpendicular to Bo. The new results here are that larger simulation boxes and longer initial whistler wavelengths yield weaker overall dissipation, consistent with linear dispersion theory predictions of decreased damping, stronger ion heating, consistent with a stronger ion Landau resonance, and weaker electron heating.Â«Â less
Verification of coronal loop diagnostics using realistic three-dimensional hydrodynamic models
Winebarger, Amy R.; Lionello, Roberto; Linker, Jon A.; Miki?, Zoran; Mok, Yung E-mail: lionel@predsci.com E-mail: mikicz@predsci.com
2014-11-10
Many different techniques have been used to characterize the plasma in the solar corona: density-sensitive spectral line ratios are used to infer the density, the evolution of coronal structures in different passbands is used to infer the temperature evolution, and the simultaneous intensities measured in multiple passbands are used to determine the emission measure distributions. All these analysis techniques assume that the intensity of the structures can be isolated through background subtraction. In this paper, we use simulated observations from a three-dimensional hydrodynamic simulation of a coronal active region to verify these diagnostics. The density and temperature from the simulation are used to generate images in several passbands and spectral lines. We identify loop structures in the simulated images and calculate the background. We then determine the density, temperature, and emission measure distribution as a function of time from the observations and compare these with the true temperature and density of the loop. We find that the overall characteristics of the temperature, density, and emission measure are recovered by the analysis methods, but the details are not. For instance, the emission measure curves calculated from the simulated observations are much broader than the true emission measure distribution, though the average temperature evolution is similar. These differences are due, in part, to a limitation of the analysis methods, but also to inadequate background subtraction.
A reduced temperature solid oxide fuel cell with three-dimensionally ordered macroporous cathode
Liang, B.; Suzuki, T.; Hamamoto, K.; Yamaguchi, T.; Sumi, H.; Fujishiro, Y.; Ingram, B. J.; Carter, J. D.
2012-01-01
Three-dimensionally ordered macroporous cathode was fabricated for a zirconia based micro-tubular solid oxide fuel cells (SOFCs). Three different cathodes (cathode A, no pore former; cathode B, with pore former (1.5 {micro}m in diameter); cathode C, with pore former (0.8 {micro}m in diameter)) were compared to investigate how the microstructure of it affected the cell performance at various operating temperatures. Micro-sized pores were well distributed within cathode B and C. The total porosity of cathode A is 35%, while it respectively reached 42 and 50% for cathodes B and C. At the same time, the specific surface area of them was 28.8 and 52.0% larger than that of the cathode A. As a result, the peak power density of the zirconia based cell, with cathode C, was 0.25 and 0.56 W cm{sup -2} at 550 and 600 C, while the respective value was just 0.11 and 0.30 W cm{sup -2} for the cell with cathode A. Thus, optimizing microstructure of cathode should be one of the best approaches for lowering the operating temperature for SOFCs.
Three-dimensional MHD simulation of the Caltech plasma jet experiment: first results
Zhai, Xiang; Bellan, Paul M.; Li, Hui; Li, Shengtai E-mail: pbellan@caltech.edu E-mail: sli@lanl.gov
2014-08-10
Magnetic fields are believed to play an essential role in astrophysical jets with observations suggesting the presence of helical magnetic fields. Here, we present three-dimensional (3D) ideal MHD simulations of the Caltech plasma jet experiment using a magnetic tower scenario as the baseline model. Magnetic fields consist of an initially localized dipole-like poloidal component and a toroidal component that is continuously being injected into the domain. This flux injection mimics the poloidal currents driven by the anode-cathode voltage drop in the experiment. The injected toroidal field stretches the poloidal fields to large distances, while forming a collimated jet along with several other key features. Detailed comparisons between 3D MHD simulations and experimental measurements provide a comprehensive description of the interplay among magnetic force, pressure, and flow effects. In particular, we delineate both the jet structure and the transition process that converts the injected magnetic energy to other forms. With suitably chosen parameters that are derived from experiments, the jet in the simulation agrees quantitatively with the experimental jet in terms of magnetic/kinetic/inertial energy, total poloidal current, voltage, jet radius, and jet propagation velocity. Specifically, the jet velocity in the simulation is proportional to the poloidal current divided by the square root of the jet density, in agreement with both the experiment and analytical theory. This work provides a new and quantitative method for relating experiments, numerical simulations, and astrophysical observation, and demonstrates the possibility of using terrestrial laboratory experiments to study astrophysical jets.
Three dimensional analysis of turbulent steam jets in enclosed structures : a CFD approach.
Ishii, M.; NguyenLe, Q.
1999-04-20
This paper compares the three-dimensional numerical simulation with the experimental data of a steam blowdown event in a light water reactor containment building. The temperature and pressure data of a steam blowdown event was measured at the Purdue University Multi-Dimensional Integrated Test Assembly (PUMA), a scaled model of the General Electric simplified Boiling Water Reactor. A three step approach was used to analyze the steam jet behavior. First, a 1-Dimensional, system level RELAP5/Mod3.2 model of the steam blowdown event was created and the results used to set the initial conditions for the PUMA blowdown experiments. Second, 2-Dimensional CFD models of the discharged steam jets were computed using PHOENICS, a commercially available CFD package. Finally, 3-Dimensional model of the PUMA drywell was created with the boundary conditions based on experimental measurements. The results of the 1-D and 2-D models were reported in the previous meeting. This paper discusses in detail the formulation and the results of the 3-Dimensional PHOENICS model of the PUMA drywell. It is found that the 3-D CFD solutions compared extremely well with the measured data.
Li Ting; Zhang Jun; Zhang Yuzong; Yang Shuhong E-mail: zjun@nao.cas.cn
2011-09-20
On 2010 August 1, a global solar event was launched involving almost the entire Earth-facing side of the Sun. This event mainly consisted of a C3.2 flare, a polar crown filament eruption, and two Earth-directed coronal mass ejections. The observations from the Solar Dynamics Observatory (SDO) and STEREO showed that all the activities were coupled together, suggesting a global character of the magnetic eruption. We reconstruct the three-dimensional geometry of the polar crown filament using observations from three different viewpoints (STEREO A, STEREO B, and SDO) for the first time. The filament undergoes two eruption processes. First, the main body of the filament rises up, while it also moves toward the low-latitude region with a change in inclination by {approx}48{sup 0} and expands only in the altitudinal and latitudinal direction in the field of view of the Atmospheric Imaging Assembly. We investigate the true velocities and accelerations of different locations along the filament and find that the highest location always has the largest acceleration during this eruption process. During the late phase of the first eruption, part of the filament material separates from the eastern leg. This material displays a projectile motion and moves toward the west at a constant velocity of 141.8 km s{sup -1}. This may imply that the polar crown filament consists of at least two groups of magnetic systems.
Pugh, J.M.; Glennie, K.W.; Williams, B.P.J. (Univ. of Aberdeen, Aberdeen (United Kingdom))
1993-09-01
The Al Liwa region of the northeast Rub Al Khali, United Arab Emirates, comprises compound crescentic draa and subcircular inland sabkhas that are flanked to their north by a sand sea of smaller dunes extending almost to the coast of the Arabian Gulf. This controlled the supply of sand from the north and influenced water-table positions within interdune areas. The draa, up to 170 m high, comprise both fine and coarse sands with a strong carbonate component, and are migrating very slowly to the south-southeast. The evaporite-encrusted interdune sabkhas often are underlain by foreset dune sands that also indicate transport to the south-southeast. The northern fringe of smaller dunes migrates southward more rapidly than the draa, but their northern supply of sand now has been cut off by flooding of the Gulf, initiating the deflation of coastal areas down to the water table. A deep-penetrating radar survey, coupled with large-scale trenching, provides a three-dimensional model of dune/interdune systems. This fieldwork aids a clearer understanding of dune/interdune heterogeneities and interconnectedness, which in turn is providing more realistic reservoir models for interwell simulation studies within the Permian Rotliegende gas fields of northwest Europe.
Wendel, M.W.; Siman-Tov, M.
1998-11-01
The Spallation Neutron Source (SNS) is a high-power accelerator-based pulsed spallation source being designed by a multilaboratory team led by Oak Ridge National Laboratory (ORNL) to achieve high fluxes of neutrons for scientific experiments. Computational fluid dynamics (CFD) is being used to analyze the SNS design. The liquid-mercury target is subjected to the neutronic (internal) heat generation that results from the proton collisions with the mercury nuclei. The liquid mercury simultaneously serves as the neutronic target medium, transports away the heat generated within itself, and cools the metallic target structure. Recirculation and stagnation zones within the target are of particular concern because of the likelihood that they will result in local hot spots. These zones exist because the most feasible target designs include a complete U-turn flow redirection. Although the primary concern is that the target is adequately cooled, the pressure drop from inlet to outlet must also be considered because pressure drop directly affects structural loading and required pumping power. Based on the current design, a three-dimensional CFD model has been developed that includes the stainless steel target structure, the liquid-mercury target flow, and the liquid-mercury cooling jacket that wraps around the nose of the target.
Kauweloa, Kevin I. Gutierrez, Alonso N.; Bergamo, Angelo; Stathakis, Sotirios; Papanikolaou, Nikos; Mavroidis, Panayiotis
2014-07-15
Purpose: There is a growing interest in the radiation oncology community to use the biological effective dose (BED) rather than the physical dose (PD) in treatment plan evaluation and optimization due to its stronger correlation with radiobiological effects. Radiotherapy patients may receive treatments involving a single only phase or multiple phases (e.g., primary and boost). Since most treatment planning systems cannot calculate the analytical BED distribution in multiphase treatments, an approximate multiphase BED expression, which is based on the total physical dose distribution, has been used. The purpose of this paper is to reveal the mathematical properties of the approximate BED formulation, relative to the true BED. Methods: The mathematical properties of the approximate multiphase BED equation are analyzed and evaluated. In order to better understand the accuracy of the approximate multiphase BED equation, the true multiphase BED equation was derived and the mathematical differences between the true and approximate multiphase BED equations were determined. The magnitude of its inaccuracies under common clinical circumstances was also studied. All calculations were performed on a voxel-by-voxel basis using the three-dimensional dose matrices. Results: Results showed that the approximate multiphase BED equation is accurate only when the dose-per-fractions (DPFs) in both the first and second phases are equal, which occur when the dose distribution does not significantly change between the phases. In the case of heterogeneous dose distributions, which significantly vary between the phases, there are fewer occurrences of equal DPFs and hence the inaccuracy of the approximate multiphase BED is greater. These characteristics are usually seen in the dose distributions being delivered to organs at risk rather than to targets. Conclusions: The finding of this study indicates that the true multiphase BED equation should be implemented in the treatment planning systems due to the inconsistent accuracy of the approximate multiphase BED equation in most of the clinical situations.
Three-dimensional NDE of VHTR core components via simulation-based testing. Final report
Guzina, Bojan; Kunerth, Dennis
2014-09-30
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 Temperature 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 components. 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 approach 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-dimensional) 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 existing 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.
New techniques for the scientific visualization of three-dimensional multi-variate and vector fields
Crawfis, R.A.
1995-10-01
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.
Effect of magnetic field on the wave dispersion relation in three-dimensional dusty plasma crystals
Yang Xuefeng [School of Mathematical Sciences, Dalian University of Technology, Dalian 116024 (China); Wang Zhengxiong [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)
2012-07-15
Three-dimensional plasma crystals under microgravity condition are investigated by taking into account an external magnetic field. The wave dispersion relations of dust lattice modes in the body centered cubic (bcc) and the face centered cubic (fcc) plasma crystals are obtained explicitly when the magnetic field is perpendicular to the wave motion. The wave dispersion relations of dust lattice modes in the bcc and fcc plasma crystals are calculated numerically when the magnetic field is in an arbitrary direction. The numerical results show that one longitudinal mode and two transverse modes are coupled due to the Lorentz force in the magnetic field. Moreover, three wave modes, i.e., the high frequency phonon mode, the low frequency phonon mode, and the optical mode, are obtained. The optical mode and at least one phonon mode are hybrid modes. When the magnetic field is neither parallel nor perpendicular to the primitive wave motion, all the three wave modes are hybrid modes and do not have any intersection points. It is also found that with increasing the magnetic field strength, the frequency of the optical mode increases and has a cutoff at the cyclotron frequency of the dust particles in the limit of long wavelength, and the mode mixings for both the optical mode and the high frequency phonon mode increase. The acoustic velocity of the low frequency phonon mode is zero. In addition, the acoustic velocity of the high frequency phonon mode depends on the angle of the magnetic field and the wave motion but does not depend on the magnetic field strength.
Three-dimensional simulations of pure deflagration models for thermonuclear supernovae
Long, Min; Jordan, George C. IV; Van Rossum, Daniel R.; Diemer, Benedikt; Graziani, Carlo; Kessler, Richard; Rich, Paul; Lamb, Don Q. [Flash Center for Computational Science, University of Chicago, Chicago, IL 60637 (United States); Meyer, Bradley, E-mail: long@flash.uchicago.edu [Department of Physics and Astronomy, Clemson University, Clemson, SC 29634 (United States)
2014-07-10
We present a systematic study of the pure deflagration model of Type Ia supernovae (SNe Ia) using three-dimensional, high-resolution, full-star hydrodynamical simulations, nucleosynthetic yields calculated using Lagrangian tracer particles, and light curves calculated using radiation transport. We evaluate the simulations by comparing their predicted light curves with many observed SNe Ia using the SALT2 data-driven model and find that the simulations may correspond to under-luminous SNe Iax. We explore the effects of the initial conditions on our results by varying the number of randomly selected ignition points from 63 to 3500, and the radius of the centered sphere they are confined in from 128 to 384 km. We find that the rate of nuclear burning depends on the number of ignition points at early times, the density of ignition points at intermediate times, and the radius of the confining sphere at late times. The results depend primarily on the number of ignition points, but we do not expect this to be the case in general. The simulations with few ignition points release more nuclear energy E{sub nuc}, have larger kinetic energies E{sub K}, and produce more {sup 56}Ni than those with many ignition points, and differ in the distribution of {sup 56}Ni, Si, and C/O in the ejecta. For these reasons, the simulations with few ignition points exhibit higher peak B-band absolute magnitudes M{sub B} and light curves that rise and decline more quickly; their M{sub B} and light curves resemble those of under-luminous SNe Iax, while those for simulations with many ignition points are not.
A STELLAR WIND ORIGIN FOR THE G2 CLOUD: THREE-DIMENSIONAL NUMERICAL SIMULATIONS
De Colle, Fabio; Raga, A. C.; Contreras-Torres, Flavio F.; Toledo-Roy, Juan C.
2014-07-10
We present three-dimensional, adaptive mesh refinement simulations of G2, a cloud of gas moving in a highly eccentric orbit toward the galactic center. We assume that G2 originates from a stellar wind interacting with the environment of the Sgr A* black hole. The stellar wind forms a cometary bubble which becomes increasingly elongated as the star approaches periastron. A few months after periastron passage, streams of material begin to accrete on the central black hole with accretion rates M-dot ?10{sup ?8} M {sub ?} yr{sup –1}. Predicted Br? emission maps and position-velocity diagrams show an elongated emission resembling recent observations of G2. A large increase in luminosity is predicted by the emission coming from the shocked wind region during periastron passage. The observations, showing a constant Br? luminosity, remain puzzling, and are explained here assuming that the emission is dominated by the free-wind region. The observed Br? luminosity (?8 × 10{sup 30} erg s{sup –1}) is reproduced by a model with a v{sub w} = 50 km s{sup –1} wind velocity and a 10{sup –7} M {sub ?} yr{sup –1} mass-loss rate if the emission comes from the shocked wind. A faster and less dense wind reproduces the Br? luminosity if the emission comes from the inner, free-wind region. The extended cometary wind bubble, largely destroyed by the tidal interaction with the black hole, reforms a few years after periastron passage. As a result, the Br? emission is more compact after periastron passage.
NONLINEAR FORCE-FREE MODELING OF A THREE-DIMENSIONAL SIGMOID OBSERVED ON THE SUN
Inoue, S.; Watari, S.; Magara, T.; Choe, G. S.
2012-03-01
In this work, we analyze the characteristics of the three-dimensional magnetic structure of a sigmoid observed over an active region (AR 10930) and followed by X-class flares. This is accomplished by combining a nonlinear force-free field (NLFFF) model of a coronal magnetic field and the high-resolution vector-field measurement of a photospheric magnetic field by Hinode. The key findings of our analysis reveal that the value of the X-ray intensity associated with the sigmoid is more sensitive to the strength of the electric current rather than the twist of the field lines. The strong electric current flows along the magnetic field lines and composes the central part of the sigmoid, even though the twist of the field lines is weak in that region. On the other hand, the outer region (i.e., the elbow part) of the sigmoid is basically occupied by field lines of strong twist and weak current density. Consequently, weak X-ray emission is observed. As the initial Ca II illumination basically occurs from the central part of the sigmoid, this region plays an important role in determining the onset mechanism of the flare despite its weak twisted field-line configuration. We also compare our results with the magnetohydrodynamic simulation for the formation of a sigmoid. Although the estimated values of the twist from the simulation are found to be a little higher than the values obtained from the NLFFF, we find that the field-line configurations generated by the simulation and NLFFF are remarkably analogous as long as we deal with the lower coronal region.
A three-dimensional carbon nano-network for high performance lithium ion batteries
Tian, Miao; Wang, Wei; Liu, Yang; Jungjohann, Katherine L.; Thomas Harris, C.; Lee, Yung -Cheng; Yang, Ronggui
2014-11-20
Three-dimensional (3D) network structure has been envisioned as a superior architecture for lithium ion battery (LIB) electrodes, which enhances both ion and electron transport to significantly improve battery performance. Herein, a 3D carbon nano-network is fabricated through chemical vapor deposition of carbon on a scalably manufactured 3D porous anodic alumina (PAA) template. As a demonstration on the applicability of 3D carbon nano-network for LIB electrodes, the low conductivity active material, TiO_{2}, is then uniformly coated on the 3D carbon nano-network using atomic layer deposition. High power performance is demonstrated in the 3D C/TiO_{2} electrodes, where the parallel tubes and gaps in the 3D carbon nano-network facilitates fast Li ion transport. A large areal capacity of ~0.37 mAhÂ·cm^{â€“2} is achieved due to the large TiO_{2} mass loading in the 60 Âµm-thick 3D C/TiO_{2} electrodes. At a test rate of C/5, the 3D C/TiO_{2} electrode with 18 nm-thick TiO_{2} delivers a high gravimetric capacity of ~240 mAh g^{â€“1}, calculated with the mass of the whole electrode. A long cycle life of over 1000 cycles with a capacity retention of 91% is demonstrated at 1C. In this study, the effects of the electrical conductivity of carbon nano-network, ion diffusion, and the electrolyte permeability on the rate performance of these 3D C/TiO_{2} electrodes are systematically studied.
Dual-spacecraft reconstruction of a three-dimensional magnetic flux rope at the Earth's magnetopause
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Hasegawa, H.; Sonnerup, B. U. Ă–.; Eriksson, S.; Nakamura, T. K. M.; Kawano, H.
2015-02-03
We present the first results of a data analysis method, developed by Sonnerup and Hasegawa (2011), for reconstructing three-dimensional (3-D), magnetohydrostatic structures from data taken as two closely spaced satellites traverse the structures. The method is applied to a magnetic flux transfer event (FTE), which was encountered on 27 June 2007 by at least three (TH-C, TH-D, and TH-E) of the five THEMIS probes near the subsolar magnetopause. The FTE was sandwiched between two oppositely directed reconnection jets under a southward interplanetary magnetic field condition, consistent with its generation by multiple X-line reconnection. The recovered 3-D field indicates that amoreÂ Â» magnetic flux rope with a diameter of ~ 3000 km was embedded in the magnetopause. The FTE flux rope had a significant 3-D structure, because the 3-D field reconstructed from the data from TH-C and TH-D (separated by ~ 390 km) better predicts magnetic field variations actually measured along the TH-E path than does the 2-D Gradâ€“Shafranov reconstruction using the data from TH-C (which was closer to TH-E than TH-D and was at ~ 1250 km from TH-E). Such a 3-D nature suggests that the field lines reconnected at the two X-lines on both sides of the flux rope are entangled in a complicated way through their interaction with each other. The generation process of the observed 3-D flux rope is discussed on the basis of the reconstruction results and the pitch-angle distribution of electrons observed in and around the FTE.Â«Â less
Three-dimensional modeling of direct-drive cryogenic implosions on OMEGA
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Igumenshchev, Igor V.; Goncharov, V. N.; Marshall, F. J.; Knauer, J. P.; Campbell, E. M.; Forrest, C. J.; Froula, D. H.; Glebov, V. Yu; McCrory, R. L.; Regan, S. P.; et al
2016-05-04
In this study, the effects of large-scale (with Legendre modes â‰˛10) laser-imposed nonuniformities in direct-drive cryogenic implosions on the OMEGA Laser System are investigated using three-dimensional hydrodynamic simulations performed using the newly developed code ASTER. Sources of these nonuniformities include an illumination pattern produced by 60 OMEGA laser beams; capsule offsets (~10 to 20 ÎĽm); and imperfect pointing, power balance, and timing of the beams (with typical Ďrms ~10 microns, 10%, and 5 ps, respectively). Two implosion designs using 26-kJ triple-picket laser pulses were studied: a nominal design, in which an 874-ÎĽm-diameter capsule is illuminated by about the same-diameter beams,moreÂ Â» and a more hydrodynamically efficient ''R75" design using a 900-ÎĽm-diameter capsule and beams of 75% of this diameter. Simulations show that nonuniformities caused by capsule offsets and beam imbalance have the largest effect on implosion performance. These nonuniformities lead to significant distortions of implosion cores, resulting in an increased residual kinetic energy and incomplete stagnation. The shape of distorted cores can be well characterized using neutron images, but is less represented by 4-8 keV x-ray images. Simulated neutron spectra from perturbed implosions show large directional variations because of bulk motion effects and up to an ~2 keV variation of the hot-spot temperature inferred from these spectra. The R75 design suffers more from illumination nonuniformities. Simulations show an advantage of this design over the nominal design when the target offset and beam power imbalance Ďrms are reduced to less than 5 ÎĽm and 5%, respectively.Â«Â less
A three-dimensional carbon nano-network for high performance lithium ion batteries
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Tian, Miao; Wang, Wei; Liu, Yang; Jungjohann, Katherine L.; Thomas Harris, C.; Lee, Yung -Cheng; Yang, Ronggui
2014-11-20
Three-dimensional (3D) network structure has been envisioned as a superior architecture for lithium ion battery (LIB) electrodes, which enhances both ion and electron transport to significantly improve battery performance. Herein, a 3D carbon nano-network is fabricated through chemical vapor deposition of carbon on a scalably manufactured 3D porous anodic alumina (PAA) template. As a demonstration on the applicability of 3D carbon nano-network for LIB electrodes, the low conductivity active material, TiO2, is then uniformly coated on the 3D carbon nano-network using atomic layer deposition. High power performance is demonstrated in the 3D C/TiO2 electrodes, where the parallel tubes and gapsmoreÂ Â» in the 3D carbon nano-network facilitates fast Li ion transport. A large areal capacity of ~0.37 mAhÂ·cmâ€“2 is achieved due to the large TiO2 mass loading in the 60 Âµm-thick 3D C/TiO2 electrodes. At a test rate of C/5, the 3D C/TiO2 electrode with 18 nm-thick TiO2 delivers a high gravimetric capacity of ~240 mAh gâ€“1, calculated with the mass of the whole electrode. A long cycle life of over 1000 cycles with a capacity retention of 91% is demonstrated at 1C. In this study, the effects of the electrical conductivity of carbon nano-network, ion diffusion, and the electrolyte permeability on the rate performance of these 3D C/TiO2 electrodes are systematically studied.Â«Â less
THREE-DIMENSIONAL RADIO AND X-RAY MODELING AND DATA ANALYSIS SOFTWARE: REVEALING FLARE COMPLEXITY
Nita, Gelu M.; Fleishman, Gregory D.; Gary, Dale E.; Kuznetsov, Alexey A.; Kontar, Eduard P.
2015-02-01
Many problems in solar physics require analysis of imaging data obtained in multiple wavelength domains with differing spatial resolution in a framework supplied by advanced three-dimensional (3D) physical models. To facilitate this goal, we have undertaken a major enhancement of our IDL-based simulation tools developed earlier for modeling microwave and X-ray emission. The enhanced software architecture allows the user to (1) import photospheric magnetic field maps and perform magnetic field extrapolations to generate 3D magnetic field models; (2) investigate the magnetic topology by interactively creating field lines and associated flux tubes; (3) populate the flux tubes with user-defined nonuniform thermal plasma and anisotropic, nonuniform, nonthermal electron distributions; (4) investigate the spatial and spectral properties of radio and X-ray emission calculated from the model; and (5) compare the model-derived images and spectra with observational data. The package integrates shared-object libraries containing fast gyrosynchrotron emission codes, IDL-based soft and hard X-ray codes, and potential and linear force-free field extrapolation routines. The package accepts user-defined radiation and magnetic field extrapolation plug-ins. We use this tool to analyze a relatively simple single-loop flare and use the model to constrain the magnetic 3D structure and spatial distribution of the fast electrons inside this loop. We iteratively compute multi-frequency microwave and multi-energy X-ray images from realistic magnetic flux tubes obtained from pre-flare extrapolations, and compare them with imaging data obtained by SDO, NoRH, and RHESSI. We use this event to illustrate the tool's use for the general interpretation of solar flares to address disparate problems in solar physics.
PLASMA JETS AND ERUPTIONS IN SOLAR CORONAL HOLES: A THREE-DIMENSIONAL FLUX EMERGENCE EXPERIMENT
Moreno-Insertis, F.
2013-07-01
A three-dimensional (3D) numerical experiment of the launching of a hot and fast coronal jet followed by several violent eruptions is analyzed in detail. These events are initiated through the emergence of a magnetic flux rope from the solar interior into a coronal hole. We explore the evolution of the emerging magnetically dominated plasma dome surmounted by a current sheet and the ensuing pattern of reconnection. A hot and fast coronal jet with inverted-Y shape is produced that shows properties comparable to those frequently observed with EUV and X-ray detectors. We analyze its 3D shape, its inhomogeneous internal structure, and its rise and decay phases, lasting for some 15-20 minutes each. Particular attention is devoted to the field line connectivities and the reconnection pattern. We also study the cool and high-density volume that appears to encircle the emerged dome. The decay of the jet is followed by a violent phase with a total of five eruptions. The first of them seems to follow the general pattern of tether-cutting reconnection in a sheared arcade, although modified by the field topology created by the preceding reconnection evolution. The two following eruptions take place near and above the strong-field concentrations at the surface. They show a twisted, {Omega}-loop-like rope expanding in height, with twist being turned into writhe, thus hinting at a kink instability (perhaps combined with a torus instability) as the cause of the eruption. The succession of a main jet ejection and a number of violent eruptions that resemble mini-CMEs and their physical properties suggest that this experiment may provide a model for the blowout jets recently proposed in the literature.
Three-dimensional modeling of diesel engine intake flow, combustion and emissions-II
Reitz, R.D.; Rutland, C.J.
1993-09-01
A three-dimensional computer code, KIVA, is being modified to include state-of-the-art submodels for diesel engine flow and combustion. Improved and/or new submodels which have already been implemented and previously reported are: Wall heat transfer with unsteadiness and compressibility, laminar-turbulent characteristic time combustion with unburned HC and Zeldo`vich NO{sub x}, and spray/wall impingement with rebounding and sliding drops. Progress on the implementation of improved spray drop drag and drop breakup models, the formulation and testing of a multistep kinetics ignition model and preliminary soot modeling results are described in this report. In addition, the use of a block structured version of KIVA to model the intake flow process is described. A grid generation scheme has been developed for modeling realistic (complex) engine geometries, and computations have been made of intake flow in the ports and combustion chamber of a two-intake-valve engine. The research also involves the use of the code to assess the effects of subprocesses on diesel engine performance. The accuracy of the predictions is being tested by comparisons with engine experiments. To date, comparisons have been made with measured engine cylinder pressure, temperature and heat flux data, and the model results are in good agreement with the experiments. Work is in progress that will allow validation of in-cylinder flow and soot formation predictions. An engine test facility is described that is being used to provide the needed validation data. Test results have been obtained showing the effect of injection rate and split injections on engine performance and emissions.
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)
2012-10-10
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.
A three-dimensional view of the thermal structure in a super-penumbral canopy
Beck, C.; Choudhary, D. P.; Rezaei, R.
2014-06-20
We investigate the three-dimensional (3D) thermal topology in a super-penumbral canopy of an active region (AR). We derive temperature stratifications in the AR by an inversion of the Ca II IR line at 854.2 nm, assuming local thermal equilibrium. We find that about half of the radially oriented fibrils in the super-penumbral canopy form short, low-lying (h < 1 Mm) loops in the 3D temperature cube. These closed loops connect from bright grains in or close to the penumbra to the photosphere a few Mms away from the sunspot. The other half of the fibrils monotonically rise with distance from the sunspot. Many of the fibrils show a central dark core and two lateral brightenings in line-core intensity images. The corresponding velocity image shows fibrils that are as wide as the fibrils seen in intensity without a lateral substructure. Additionally, we study a feature from a different class of structures without prominent mass flows. Its 3D topology is formed by two parallel, closed loops that connect patches of opposite polarity. We present evidence that the inverse Evershed flow into the sunspot in the lower chromosphere is the consequence of siphon flows along short loops that connect photospheric foot points. The dark-cored structure of the chromospheric fibrils cannot have a convective origin because of their location above regular granulation. The dark core most likely results from an opacity difference between the central axis and the lateral edges caused by the significant flow speed along the fibrils.
Three-Dimensional Reconstruction of the Giant Mimivirus Particle with an X-Ray Free-Electron Laser
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
Ekeberg, Tomas
2015-05-26
This dataset contains the diffraction patterns that were used for the first three-dimensional reconstruction of a virus using FEL data. The sample was the giant mimivirus particle, which is one of the largest known viruses with a diameter of 450 nm. The dataset consists of the 198 diffraction patterns that were used in the analysis.
Yu, L.; Batlle, F.
2011-12-15
Highlights: > A quasi-three-dimensional slope stability analysis method was proposed. > The proposed method is a good engineering tool for 3D slope stability analysis. > Factor of safety from 3D analysis is higher than from 2D analysis. > 3D analysis results are more sensitive to cohesion than 2D analysis. - Abstract: Limited space for accommodating the ever increasing mounds of municipal solid waste (MSW) demands the capacity of MSW landfill be maximized by building landfills to greater heights with steeper slopes. This situation has raised concerns regarding the stability of high MSW landfills. A hybrid method for quasi-three-dimensional slope stability analysis based on the finite element stress analysis was applied in a case study at a MSW landfill in north-east Spain. Potential slides can be assumed to be located within the waste mass due to the lack of weak foundation soils and geosynthetic membranes at the landfill base. The only triggering factor of deep-seated slope failure is the higher leachate level and the relatively high and steep slope in the front. The valley-shaped geometry and layered construction procedure at the site make three-dimensional slope stability analyses necessary for this landfill. In the finite element stress analysis, variations of leachate level during construction and continuous settlement of the landfill were taken into account. The 'equivalent' three-dimensional factor of safety (FoS) was computed from the individual result of the two-dimensional analysis for a series of evenly spaced cross sections within the potential sliding body. Results indicate that the hybrid method for quasi-three-dimensional slope stability analysis adopted in this paper is capable of locating roughly the spatial position of the potential sliding mass. This easy to manipulate method can serve as an engineering tool in the preliminary estimate of the FoS as well as the approximate position and extent of the potential sliding mass. The result that FoS obtained from three-dimensional analysis increases as much as 50% compared to that from two-dimensional analysis implies the significance of the three-dimensional effect for this study-case. Influences of shear parameters, time elapse after landfill closure, leachate level as well as unit weight of waste on FoS were also investigated in this paper. These sensitivity analyses serve as the guidelines of construction practices and operating procedures for the MSW landfill under study.
Valentini, Anna Lia; Gui, Benedetta; D'Agostino, Giuseppe Roberto; Mattiucci, Giancarlo; Clementi, Valeria; Di Molfetta, Ippolita Valentina; Bonomo, Pierluigi; Mantini, Giovanna
2012-11-01
Purpose: To correlate results of three-dimensional magnetic resonance spectroscopic imaging (MRSI) with prostate-specific antigen (PSA) levels and time since external beam irradiation (EBRT) in patients treated with long-term hormone therapy (HT) and EBRT for locally advanced disease to verify successful treatment by documenting the achievement of metabolic atrophy (MA). Methods and Materials: Between 2006 and 2008, 109 patients were consecutively enrolled. MA was assessed by choline and citrate peak area-to-noise-ratio <5:1. Cancerous metabolism (CM) was defined by choline-to-creatine ratio >1.5:1 or choline signal-to-noise-ratio >5:1. To test the strength of association between MRSI results and the time elapsed since EBRT (TEFRT), PSA levels, Gleason score (GS), and stage, logistic regression (LR) was performed. p value <0.05 was statistically significant. The patients' outcomes were verified in 2011. Results: MRSI documented MA in 84 of 109 and CM in 25 of 109 cases. LR showed that age, GS, stage, and initial and recent PSA had no significant impact on MRSI results which were significantly related to PSA values at the time of MRSI and to TEFRT. Patients were divided into three groups according to TEFRT: <1 year, 1-2 years, and >2 years. MA was detected in 54.1% of patients of group 1, 88.9% of group 2, and in 94.5% of group 3 (100% when PSA nadir was reached). CM was detected in 50% of patients with reached PSA nadir in group 1. Local relapse was found in 3 patients previously showing CM at long TEFRT. Conclusion: MA detection, indicative of successful treatment because growth of normal or abnormal cells cannot occur without metabolism, increases with decreasing PSA levels and increasing time on HT after EBRT. This supports long-term HT in advanced prostate cancer. Larger study series are needed to assess whether MRSI could predict local relapse by detecting CM at long TEFRT.
Three-dimensional x-ray fluorescence mapping of a gold nanoparticle-loaded phantom
Ren, Liqiang; Wu, Di; Li, Yuhua; Liu, Hong; Wang, Ge; Wu, Xizeng
2014-03-15
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 Î±} fluorescence x-rays (65.99 â€“69.80 keV) acquired after background subtraction are well calibrated, and finally the unattenuated K{sub Î±} 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 Î±} 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 Integration Technology for Advanced Focal Planes and Integrated Circuits
Keast, Craig
2007-02-28
Over the last five years MIT Lincoln Laboratory (MIT-LL) has developed a three-dimensional (3D) circuit integration technology that exploits the advantages of silicon-on-insulator (SOI) technology to enable wafer-level stacking and micrometer-scale electrical interconnection of fully fabricated circuit wafers. Advanced focal plane arrays have been the first applications to exploit the benefits of this 3D integration technology because the massively parallel information flow present in 2D imaging arrays maps very nicely into a 3D computational structure as information flows from circuit-tier to circuit-tier in the z-direction. To date, the MIT-LL 3D integration technology has been used to fabricate four different focal planes including: a 2-tier 64 x 64 imager with fully parallel per-pixel A/D conversion; a 3-tier 640 x 480 imager consisting of an imaging tier, an A/D conversion tier, and a digital signal processing tier; a 2-tier 1024 x 1024 pixel, 4-side-abutable imaging modules for tiling large mosaic focal planes, and a 3-tier Geiger-mode avalanche photodiode (APD) 3-D LIDAR array, using a 30 volt APD tier, a 3.3 volt CMOS tier, and a 1.5 volt CMOS tier. Recently, the 3D integration technology has been made available to the circuit design research community through DARPA-sponsored Multiproject fabrication runs. The first Multiproject Run (3DL1) completed fabrication in early 2006 and included over 30 different circuit designs from 21 different research groups. 3D circuit concepts explored in this run included stacked memories, field programmable gate arrays (FPGAs), and mixed-signal circuits. The second Multiproject Run (3DM2) is currently in fabrication and includes particle detector readouts designed by Fermilab. This talk will provide a brief overview of MIT-LL's 3D-integration process, discuss some of the focal plane applications where the technology is being applied, and provide a summary of some of the Multiproject Run circuit results.
Soft-Lithographical Fabrication of Three-dimensional Photonic Crystals in the Optical Regime
Jae-Hwang Lee
2006-08-09
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.
Nagakura, Hiroki [Yukawa Institute for Theoretical Physics, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502 (Japan); Sumiyoshi, Kohsuke [Numazu College of Technology, Ooka 3600, Numazu, Shizuoka 410-8501 (Japan); Yamada, Shoichi [Advanced Research Institute for Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555 (Japan)
2014-10-01
We propose a novel numerical method for solving multi-dimensional, special relativistic Boltzmann equations for neutrinos coupled with hydrodynamics equations. This method is meant to be applied to simulations of core-collapse supernovae. We handle special relativity in a non-conventional way, taking account of all orders of v/c. Consistent treatment of the advection and collision terms in the Boltzmann equations has been a challenge, which we overcome by employing two different energy grids: Lagrangian remapped and laboratory fixed grids. We conduct a series of basic tests and perform a one-dimensional simulation of core-collapse, bounce, and shock-stall for a 15 M {sub ?} progenitor model with a minimum but essential set of microphysics. We demonstrate in the latter simulation that our new code is capable of handling all phases in core-collapse supernova. For comparison, a non-relativistic simulation is also conducted with the same code, and we show that they produce qualitatively wrong results in neutrino transfer. Finally, we discuss a possible incorporation of general relativistic effects into our method.
Three-dimensional stationary cyclic symmetric Einstein-Maxwell solutions; black holes
Garcia, Alberto A.
2009-09-15
From a general metric for stationary cyclic symmetric gravitational fields coupled to Maxwell electromagnetic fields within the (2 + 1)-dimensional gravity the uniqueness of wide families of exact solutions is established. Among them, all uniform electromagnetic solutions possessing electromagnetic fields with vanishing covariant derivatives, all fields having constant electromagnetic invariants F{sub {mu}}{sub {nu}}F{sup {mu}}{sup {nu}} and T{sub {mu}}{sub {nu}}T{sup {mu}}{sup {nu}}, the whole classes of hybrid electromagnetic solutions, and also wide classes of stationary solutions are derived for a third-order nonlinear key equation. Certain of these families can be thought of as black hole solutions. For the most general set of Einstein-Maxwell equations, reducible to three nonlinear equations for the three unknown functions, two new classes of solutions - having anti-de Sitter spinning metric limit - are derived. The relationship of various families with those reported by different authors' solutions has been established. Among the classes of solutions with cosmological constant a relevant place is occupied by the electrostatic and magnetostatic Peldan solutions, the stationary uniform and spinning Clement classes, the constant electromagnetic invariant branches with the particular Kamata-Koikawa solution, the hybrid cyclic symmetric stationary black hole fields, and the non-less important solutions generated via SL(2,R)-transformations where the Clement spinning charged solution, the Martinez-Teitelboim-Zanelli black hole solution, and Dias-Lemos metric merit mention.
Ren, Shengdong; Huang, Qiuping; Li, Bincheng
2013-12-28
A three-dimensional transient model for time-domain (modulated) free-carrier absorption (FCA) measurement was developed to describe the transport dynamics of photo-generated excess carriers in silicon (Si) wafers. With the developed transient model, numerical simulations were performed to investigate the dependences of the waveforms of the transient FCA signals on the electronic transport parameters of Si wafers and the geometric parameters of the FCA experiment. Experimental waveforms of FCA signals of both n- and p-type Si wafers with resistivity ranging 1â€“38 Î©Â·cm were then fitted to the three-dimensional transient model to extract simultaneously and unambiguously the transport parameters of Si wafers, namely, the carrier lifetime, the carrier diffusion coefficient, and the front surface recombination velocity via multi-parameter fitting. A basic agreement between the extracted parameter values and the literature values was obtained.
Bligh, T.P.; Knoth, T.P.
1983-01-01
This paper presents data from one-, two-, and three-dimensional temperature fields in the soil surrounding an earth-sheltered house. The construction and installation of the temperature sensors is discussed, and the sources of error are evaluated. The precision of the measured temperatures is shown to be + or - 0.12/sup 0/C. Twenty-four hours of data from the one-dimensional temperature field in the roof soil are presented in the form of tautochrones. Data from cross-sections of the two- and three-dimensional temperature fields are presented as isotherms taken at approximately one-month intervals during winter and spring. The data show that extended roof insulation impedes heat flow to the ground surface in winter but allows heat to flow to the cool soil depths in summer.
W. Steven Holbrook
2004-11-11
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.
THREE-DIMENSIONAL THERMAL MODELING ANALYSIS OF CST MEDIA FOR THE SMALL ION EXCHANGE PROJECT
Lee, S.; King, W.
2011-09-12
The Small Column Ion Exchange (SCIX) project is designed to accelerate closure of High Level Waste (HLW) tanks at the Savannah River Site (SRS). The SRS tanks store HLW in three forms: sludge, saltcake, and supernate. An in-tank ion exchange process is being designed to treat supernate and dissolved saltcake waste. Through this process, radioactive cesium from the salt solution is adsorbed into Crystalline Silicotitanate (CST) ion exchange media packed within a flow-through column. A packed column loaded with radioactive cesium generates significant heat from radiolytic decay. The waste supernate solution within the ion exchange bed will boil around 120 C. Solution superheating above the boiling point within the column could lead to violent hazardous energy releases. System heating from loaded CST is also of concern in other process modules, such as the waste tank. Due to tank structural integrity concerns, the wall temperature limit for the SRS waste tanks is 100 C. The transfer of cesium-loaded CST to the tank could result in localized hot spots on the tank floor and walls which may exceed this limit. As a result, thermal modeling calculations have been conducted to predict the maximum temperatures achievable both in the column and in the waste tank. As specified in the associated Technical Task Plan, one objective of the present work was to compute temperature distributions within the ion exchange column module under accident scenarios including loss of salt solution flow through the bed and loss of coolant system flow. The column modeling domain and the scope of the calculations in this case were broadened relative to previous two-dimensional calculations to include vertical temperature distributions within the packed bed of ion exchange media as well as the upper column plenum region containing only fluid. The baseline design conditions and in-column modeling domain for the ion-exchange column module are shown in Figure 1. These evaluations assumed the maximum bounding cesium loading considered possible based on current knowledge regarding CST media and the anticipated feed compositions. Since this cesium loading was considerably higher than the nominal loading conditions in SRS waste, cases with lower loading were also evaluated. Modeling parameters were the same as those used previously unless otherwise indicated. The current model does not capture multi-phase cooling mechanisms operative when solution boiling occurs. This feature is conservative in the sense that it does not account for the large cooling effects associated with phase transfer. However, the potential transfer of heat to the plenum region associated with vertical bubble ascension through the column during boiling is also neglected. Thermal modeling calculations were also performed for the entire waste storage tank for the case where loaded and ground CST was transferred to the tank. The modeling domain used for the in-tank calculations is provided in Figure 2. The in-tank domain is based on SRS Tank 41, which is a Type-IIIA tank. Temperature distributions were evaluated for cylindrical, ground CST mounds located on the tank floor. Media grinding is required prior to vitrification processing of the CST in the SRS Defense Waste Processing Facility (DWPF). The location of the heat source region on the tank floor due to the accumulation of CST material was assumed to be just under the grinder. The shape of the CST mound was assumed to be cylindrical. This shape is believed to be most representative of the actual mound shape formed in the tank, given that submersible mixing pumps will be available for media dispersion. Alternative configurations involving other geometrical shapes for the CST mound were evaluated in the previous work. Sensitivity analysis for the in-tank region was performed for different amounts of CST media. As was the case for the in-column model, the in-tank model does not include multi-phase cooling mechanisms operative when solution boiling occurs. The in-column and the in-tank evaluations incorporated recently updated maximum cesium loading levels calculated using the current SCIX feed compositions, which resulted in significantly higher cesium loading than previously calculated. The calculations were conducted to ensure conservative predictions for the maximum temperatures achievable using the current baseline design. The degree of conservatism was reduced for in-column calculations relative to the previous work by using a three-dimensional modeling approach and selecting parameters which were nearer to expected conditions. The degree of conservatism for the in-tank calculations was also reduced by lowering the soil penetration depth below the tank from 150 to 20 feet. The primary goals of the extended thermal modeling effort were to determine whether fluid boiling or superheating are possible within the column module and to determine the maximum floor temperatures within the tank loaded with spent CST.
Jacqmin, R.P.
1991-12-10
The safety and optimal performance of large, commercial, light-water reactors require the knowledge at all time of the neutron-flux distribution in the core. In principle, this information can be obtained by solving the time-dependent neutron diffusion equations. However, this approach is complicated and very expensive. Sufficiently accurate, real-time calculations (time scale of approximately one second) are not yet possible on desktop computers, even with fast-running, nodal kinetics codes. A semi-experimental, nodal synthesis method which avoids the solution of the time-dependent, neutron diffusion equations is described. The essential idea of this method is to approximate instantaneous nodal group-fluxes by a linear combination of K, precomputed, three-dimensional, static expansion-functions. The time-dependent coefficients of the combination are found from the requirement that the reconstructed flux-distribution agree in a least-squares sense with the readings of J ({ge}K) fixed, prompt-responding neutron-detectors. Possible numerical difficulties with the least-squares solution of the ill-conditioned, J-by-K system of equations are brought under complete control by the use of a singular-value-decomposition technique. This procedure amounts to the rearrangement of the original, linear combination of K expansion functions into an equivalent more convenient, linear combination of R ({le}K) orthogonalized modes'' of decreasing magnitude. Exceedingly small modes are zeroed to eliminate any risk of roundoff-error amplification, and to assure consistency with the limited accuracy of the data. Additional modes are zeroed when it is desirable to limit the sensitivity of the results to measurement noise.
Jacqmin, R.P.
1991-12-10
The safety and optimal performance of large, commercial, light-water reactors require the knowledge at all time of the neutron-flux distribution in the core. In principle, this information can be obtained by solving the time-dependent neutron diffusion equations. However, this approach is complicated and very expensive. Sufficiently accurate, real-time calculations (time scale of approximately one second) are not yet possible on desktop computers, even with fast-running, nodal kinetics codes. A semi-experimental, nodal synthesis method which avoids the solution of the time-dependent, neutron diffusion equations is described. The essential idea of this method is to approximate instantaneous nodal group-fluxes by a linear combination of K, precomputed, three-dimensional, static expansion-functions. The time-dependent coefficients of the combination are found from the requirement that the reconstructed flux-distribution agree in a least-squares sense with the readings of J ({ge}K) fixed, prompt-responding neutron-detectors. Possible numerical difficulties with the least-squares solution of the ill-conditioned, J-by-K system of equations are brought under complete control by the use of a singular-value-decomposition technique. This procedure amounts to the rearrangement of the original, linear combination of K expansion functions into an equivalent more convenient, linear combination of R ({le}K) orthogonalized ``modes`` of decreasing magnitude. Exceedingly small modes are zeroed to eliminate any risk of roundoff-error amplification, and to assure consistency with the limited accuracy of the data. Additional modes are zeroed when it is desirable to limit the sensitivity of the results to measurement noise.
Electromagnetic energy conversion in downstream fronts from three dimensional kinetic reconnection
Lapenta, Giovanni [Departement Wiskunde, KU Leuven, Universiteit Leuven (Belgium)] [Departement Wiskunde, KU Leuven, Universiteit Leuven (Belgium); Goldman, Martin; Newman, David [University of Colorado, Colorado 80309 (United States)] [University of Colorado, Colorado 80309 (United States); Markidis, Stefano [High Performance Computing and Visualization (HPCViz) Department, KTH Royal Institute of Technology, Stockholm (Sweden)] [High Performance Computing and Visualization (HPCViz) Department, KTH Royal Institute of Technology, Stockholm (Sweden); Divin, Andrey [Swedish Institute of Space Physics, Uppsala (Sweden)] [Swedish Institute of Space Physics, Uppsala (Sweden)
2014-05-15
The electromagnetic energy equation is analyzed term by term in a 3D simulation of kinetic reconnection previously reported by Vapirev et al. [J. Geophys. Res.: Space Phys. 118, 1435 (2013)]. The evolution presents the usual 2D-like topological structures caused by an initial perturbation independent of the third dimension. However, downstream of the reconnection site, where the jetting plasma encounters the yet unperturbed pre-existing plasma, a downstream front is formed and made unstable by the strong density gradient and the unfavorable local acceleration field. The energy exchange between plasma and fields is most intense at the instability, reaching several pW/m{sup 3}, alternating between load (energy going from fields to particles) and generator (energy going from particles to fields) regions. Energy exchange is instead purely that of a load at the reconnection site itself in a region focused around the x-line and elongated along the separatrix surfaces. Poynting fluxes are generated at all energy exchange regions and travel away from the reconnection site transporting an energy signal of the order of about S?10{sup ?3}W/m{sup 2}.
Yelles Chaouche, L.; Kuckein, C.; Martinez Pillet, V.; Moreno-Insertis, F.
2012-03-20
The three-dimensional structure of an active region filament is studied using nonlinear force-free field extrapolations based on simultaneous observations at a photospheric and a chromospheric height. To that end, we used the Si I 10827 A line and the He I 10830 A triplet obtained with the Tenerife Infrared Polarimeter at the Vacuum Tower Telescope (Tenerife). The two extrapolations have been carried out independently from each other and their respective spatial domains overlap in a considerable height range. This opens up new possibilities for diagnostics in addition to the usual ones obtained through a single extrapolation from, typically, a photospheric layer. Among those possibilities, this method allows the determination of an average formation height of the He I 10830 A signal of Almost-Equal-To 2 Mm above the surface of the Sun. It allows, as well, a cross-check of the obtained three-dimensional magnetic structures to verify a possible deviation from the force-free condition, especially at the photosphere. The extrapolations yield a filament formed by a twisted flux rope whose axis is located at about 1.4 Mm above the solar surface. The twisted field lines make slightly more than one turn along the filament within our field of view, which results in 0.055 turns Mm{sup -1}. The convex part of the field lines (as seen from the solar surface) constitutes dips where the plasma can naturally be supported. The obtained three-dimensional magnetic structure of the filament depends on the choice of the observed horizontal magnetic field as determined from the 180 Degree-Sign solution of the azimuth. We derive a method to check for the correctness of the selected 180 Degree-Sign ambiguity solution.
Zhang, Jinping; Chen, Yuping Hu, Mengning; Chen, Xianfeng
2015-02-14
In this paper, an improved three-dimensional two-temperature model for multi-pulse femtosecond laser ablation of aluminum was proposed and proved in our experiment. Aiming to achieve hole-drilling with a high ratio of depth/entrance diameter in vacuum, this model can predict the depth and radius of the drilled holes precisely when employing different laser parameters. Additionally, for multi-pulse laser ablation, we found that the laser fluence and number of pulses are the dominant parameters and the multi-pulse ablation threshold is much lower than the single-pulse one, which will help to obtain high-quality holes.
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Effect of resonant magnetic perturbations on three dimensional equilibria in the Madison Symmetric Torus reversed-field pinch S. Munaretto, B. E. Chapman, M. D. Nornberg, J. Boguski, A. M. DuBois, A. F. Almagri, and J. S. Sarff Citation: Physics of Plasmas 23, 056104 (2016); doi: 10.1063/1.4943524 View online: http://dx.doi.org/10.1063/1.4943524 View Table of Contents: http://scitation.aip.org/content/aip/journal/pop/23/5?ver=pdfcov Published by the AIP Publishing Articles you may be interested
A three-dimensional spatial model of plutonium in soil near Rocky Flats, Colorado
Webb, S.B.; Ibrahim, S.A.; Whicker, F.W.
1997-08-01
The horizontal and depth distribution of plutonium was measured in soil east of the Rocky Flats Environmental Technology Site (formerly the Rocky Flats Plant) near Denver, Colorado, during 1992-1994. The study area was centered on the eastern plume of plutonium contamination and included transacts extending from 0.2 km east of the primary origin of the contamination (the 903 Pad) to distances of up to 19 km northeast, east, southeast and south-southeast of the 903 Pad. Soil was collected in 3 cm layers down to 21 cm at exponentially increasing distances along the four transacts. Plutonium concentrations decreased rapidly with depth, distance from the 903 Pad, and angle from due east. Depth distributions were independent of distance and angle from the 903 Pad, and our profile model can be used to adjust to a common basis, historical measurements made from sampling to different depths. Based on a total of {approximately}1,400 independent measurements, mathematical functions were developed to describe the distance, directional, and depth relationships. These equations, combined with soil density and rock measurements, provided a new method to estimate the plutonium concentration or total deposition per unit area anywhere within the study area. Total deposition per unit area measurements at 50 sites provided an independent test of the model`s predictive accuracy. Sampling coefficients of variation based on replicate samples at the main sampling locations averaged 33%, but ranged from 12 to 98%. The analytical measurement coefficient of variation averaged 8%. Mean 0-3 cm soil concentrations of {sup 239}Pu among 10 Front Range {open_quotes}background{close_quotes} and 11 community locations near Rocky Flats were 2.1 and 2.3 Bq kg{sup -1}, respectively. 45 refs., 8 figs., 1 tab.
Carrington, David Bradley; Monayem, A. K. M.; Mazumder, H.; Heinrich, Juan C.
2015-03-05
A three-dimensional finite element method for the numerical simulations of fluid flow in domains containing moving rigid objects or boundaries is developed. The method falls into the general category of Arbitrary Lagrangian Eulerian methods; it is based on a fixed mesh that is locally adapted in the immediate vicinity of the moving interfaces and reverts to its original shape once the moving interfaces go past the elements. The moving interfaces are defined by separate sets of marker points so that the global mesh is independent of interface movement and the possibility of mesh entanglement is eliminated. The results is a fully robust formulation capable of calculating on domains of complex geometry with moving boundaries or devises that can also have a complex geometry without danger of the mesh becoming unsuitable due to its continuous deformation thus eliminating the need for repeated re-meshing and interpolation. Moreover, the boundary conditions on the interfaces are imposed exactly. This work is intended to support the internal combustion engines simulator KIVA developed at Los Alamos National Laboratories. The model's capabilities are illustrated through application to incompressible flows in different geometrical settings that show the robustness and flexibility of the technique to perform simulations involving moving boundaries in a three-dimensional domain.
Foxall, W.
1992-11-01
Crystal fault zones exhibit spatially heterogeneous slip behavior at all scales, slip being partitioned between stable frictional sliding, or fault creep, and unstable earthquake rupture. An understanding the mechanisms underlying slip segmentation is fundamental to research into fault dynamics and the physics of earthquake generation. This thesis investigates the influence that large-scale along-strike heterogeneity in fault zone lithology has on slip segmentation. Large-scale transitions from the stable block sliding of the Central 4D Creeping Section of the San Andreas, fault to the locked 1906 and 1857 earthquake segments takes place along the Loma Prieta and Parkfield sections of the fault, respectively, the transitions being accomplished in part by the generation of earthquakes in the magnitude range 6 (Parkfield) to 7 (Loma Prieta). Information on sub-surface lithology interpreted from the Loma Prieta and Parkfield three-dimensional crustal velocity models computed by Michelini (1991) is integrated with information on slip behavior provided by the distributions of earthquakes located using, the three-dimensional models and by surface creep data to study the relationships between large-scale lithological heterogeneity and slip segmentation along these two sections of the fault zone.
Romallosa, Kristine Marie; Bantang, Johnrob; Saloma, Caesar
2003-09-01
Via the Richards-Wolf vector diffraction theory, we analyze the three-dimensional intensity distribution of the focal volume that is produced by a strongly focused 750-nm beam of ultrafast, Gaussian-shaped optical pulses (10{sup -9} s{>=} pulse width {tau}{>=}1 fs=10{sup -15} s). Knowledge of the three-dimensional distribution near focus is essential in determining the diffraction-limited resolution of an optical microscope. The optical spectrum of a short pulse is characterized by side frequencies about the carrier frequency. The effect of spectral broadening on the focused intensity distribution is evaluated via the Linfoot's criteria of fidelity, structural content, and correlation quality and with reference to a 750-nm cw focused beam. Different values are considered for {tau} and numerical aperture of the focusing lens (0.1{<=}X{sub NA}{<=}1.2). At X{sub NA}=0.8, rapid deterioration of the focused intensity distribution is observed at {tau}=1.2 fs. This happens because a 750-nm optical pulse with {tau}=1.2 fs has an associated coherence length of 359.7 nm which is less than the Nyquist sampling interval of 375 nm that is required to sample 750 nm sinusoid without loss of information. The ill-effects of spectral broadening is weaker in two-photon excitation microscope than in its single-photon counterpart for the same focusing lens and light source.
Laplace plane modifications arising from solar radiation pressure
Rosengren, Aaron J.; Scheeres, Daniel J.
2014-05-01
The dynamical effects of solar radiation pressure (SRP) in the solar system have been rigorously studied since the early 1900s. This non-gravitational perturbation plays a significant role in the evolution of dust particles in circumplanetary orbits, as well as in the orbital motion about asteroids and comets. For gravitationally dominated orbits, SRP is negligible and the resulting motion is largely governed by the oblateness of the primary and the attraction of the Sun. The interplay between these gravitational perturbations gives rise to three mutually perpendicular planes of equilibrium for circular satellite orbits. The classical Laplace plane lies between the equatorial and orbital planes of the primary, and is the mean reference plane about whose axis the pole of a satellite's orbit precesses. From a previously derived solution for the secular motion of an orbiter about a small body in a SRP dominated environment, we find that SRP acting alone will cause an initially circular orbit to precess around the pole of the primary's heliocentric orbital plane. When the gravitational and non-gravitational perturbations act in concert, the resulting equilibrium planes turn out to be qualitatively different, in some cases, from those obtained without considering the radiation pressure. The warping of the surfaces swept out by the modified equilibria as the semi-major axis varies depends critically on the cross-sectional area of the body exposed. These results, together with an adiabatic invariance argument on Poynting-Robertson drag, provide a natural qualitative explanation for the initial albedo dichotomy of Saturn's moon, Iapetus.
Ozoe, H. ); Sato, N. ); Churchill, S.W. )
1990-01-01
This paper reports general two- and three-dimensional models derived and solved numerically for the thermoacoustical convection that is generated in a compressible fluid by rapid heating of one of the vertical enclosing walls.
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)
2014-08-15
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.
Gao Xiumin
2007-01-10
I thank Canales et al. very much for their attention to the effect of the phase apodizer, especially for their comment on my paper [Appl. Opt. 44, 4870(2005)]. I reinvestigated the three-dimensional intensity distribution by a pure phase-shifting apodizer, and the main results on focal shift, focal split, and three intensity distributions are correct.However, the changing principle of the Strehl ratio is wrong, as Canales et al. show in their comment. Here, I show the cause leading to the erroneous result and give the correct dependence of the Strehl ratio on the inner radius and relative waist width. I am very sorry for the incorrect results in the paper.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
King, Travis L.; Gatimu, Enid N.; Bohn, Paul W.
2009-01-02
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 nanoporesmoreÂ Â» 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.Â«Â less
Three-dimensional charge density wave order in YBa2Cu3O6.67 at high magnetic fields
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Gerber, S.; Jang, H.; Nojiri, H.; Matsuzawa, S.; Yasumura, H.; Bonn, D. A.; Liang, R.; Hardy, W. N.; Islam, Z.; Mehta, A.; et al
2015-11-20
In this study, charge density wave (CDW) correlations have recently been shown to universally exist in cuprate superconductors. However, their nature at high fields inferred from nuclear magnetic resonance is distinct from that measured by x-ray scattering at zero and low fields. Here we combine a pulsed magnet with an x-ray free electron laser to characterize the CDW in YBa2Cu3O6.67 via x-ray scattering in fields up to 28 Tesla. While the zero-field CDW order, which develops below T ~ 150 K, is essentially two-dimensional, at lower temperature and beyond 15 Tesla, another three-dimensionally ordered CDW emerges. The field-induced CDW onsetsmoreÂ Â» around the zero-field superconducting transition temperature, yet the incommensurate in-plane ordering vector is field-independent. This implies that the two forms of CDW and high-temperature superconductivity are intimately linked.Â«Â less
Niida, Chisato; Nakajima, Masakazu; Endo, Yasuki; Sumiyoshi, Yoshihiro; Ohshima, Yasuhiro; Kohguchi, Hiroshi
2014-03-14
Pure rotational transitions of the Ar–CS van der Waals complex have been observed by Fourier Transform Microwave (FTMW) and FTMW-millimeter wave double resonance spectroscopy. Rotational transitions of v{sub s} = 0, 1, and 2 were able to be observed for normal CS, together with those of C{sup 34}S in v{sub s} = 0, where v{sub s} stands for the quantum number of the CS stretching vibration. The observed transition frequencies were analyzed by a free rotor model Hamiltonian, where rovibrational energies were calculated as dynamical motions of the three nuclei on a three-dimensional potential energy surface, expressed by analytical functions with 57 parameters. Initial values for the potential parameters were obtained by high-level ab initio calculations. Fifteen parameters were adjusted among the 57 parameters to reproduce all the observed transition frequencies with the standard deviation of the fit to be 0.028 MHz.
Shirley, C.; Pohlmann, K.; Andricevic, R.
1996-09-01
Geological and geophysical data are used with the sequential indicator simulation algorithm of Gomez-Hernandez and Srivastava to produce multiple, equiprobable, three-dimensional maps of informal hydrostratigraphic units at the Frenchman Flat Corrective Action Unit, Nevada Test Site. The upper 50 percent of the Tertiary volcanic lithostratigraphic column comprises the study volume. Semivariograms are modeled from indicator-transformed geophysical tool signals. Each equiprobable study volume is subdivided into discrete classes using the ISIM3D implementation of the sequential indicator simulation algorithm. Hydraulic conductivity is assigned within each class using the sequential Gaussian simulation method of Deutsch and Journel. The resulting maps show the contiguity of high and low hydraulic conductivity regions.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Makedonska, Nataliia; Painter, Scott L.; Bui, Quan M.; Gable, Carl W.; Karra, Satish
2015-09-16
The discrete fracture network (DFN) model is a method to mimic discrete pathways for fluid flow through a fractured low-permeable rock mass, and may be combined with particle tracking simulations to address solute transport. However, experience has shown that it is challenging to obtain accurate transport results in three-dimensional DFNs because of the high computational burden and difficulty in constructing a high-quality unstructured computational mesh on simulated fractures. We present a new particle tracking capability, which is adapted to control volume (Voronoi polygons) flow solutions on unstructured grids (Delaunay triangulations) on three-dimensional DFNs. The locally mass-conserving finite-volume approach eliminates massmoreÂ Â» balance-related problems during particle tracking. The scalar fluxes calculated for each control volume face by the flow solver are used to reconstruct a Darcy velocity at each control volume centroid. The groundwater velocities can then be continuously interpolated to any point in the domain of interest. The control volumes at fracture intersections are split into four pieces, and the velocity is reconstructed independently on each piece, which results in multiple groundwater velocities at the intersection, one for each fracture on each side of the intersection line. This technique enables detailed particle transport representation through a complex DFN structure. Verified for small DFNs, the new simulation capability enables numerical experiments on advective transport in large DFNs to be performed. As a result, we demonstrate this particle transport approach on a DFN model using parameters similar to those of crystalline rock at a proposed geologic repository for spent nuclear fuel in Forsmark, Sweden.Â«Â less
Atherton, C.S.
1995-01-05
Two of the most important chemically reactive tropospheric gases are ozone (O{sub 3}) and the hydroxyl radical (OH). Although ozone in the stratosphere is a necessary protector against the sun`s radiation, tropospheric ozone is actually a pollutant which damages materials and vegetation, acts as a respiratory irritant, and is a greenhouse gas. One of the two main sources of ozone in the troposphere is photochemical production. The photochemistry is initiated when hydrocarbons and carbon monoxide (CO) react with nitrogen oxides (NO{sub x} = NO + NO{sub 2}) in the presence of sunlight. Reaction with the hydroxyl radical, OH, is the main sink for many tropospheric gases. The hydroxyl radical is highly reactive and has a lifetime on the order of seconds. Its formation is initiated by the photolysis of tropospheric ozone. Tropospheric chemistry involves a complex, non-linear set of chemical reactions between atmospheric species that vary substantially in time and space. To model these and other species on a global scale requires the use of a global, three-dimensional chemistry, transport, and deposition (CTD) model. In this work, I developed two such three dimensional CTD models. The first model incorporated the chemistry necessary to model tropospheric ozone production from the reactions of nitrogen oxides with carbon monoxide (CO) and methane (CH{sub 4}). The second also included longer-lived alkane species and the biogenic hydrocarbon isoprene, which is emitted by growing plants and trees. The models` ability to predict a number of key variables (including the concentration of O{sub 3}, OH, and other species) were evaluated. Then, several scenarios were simulated to understand the change in the chemistry of the troposphere since preindustrial times and the role of anthropogenic NO{sub x} on present day conditions.
Parker, S.
1995-10-24
A filmless X-ray imaging system includes at least one X-ray source, upper and lower collimators, and a solid-state detector array, and can provide three-dimensional imaging capability. The X-ray source plane is distance z{sub 1} above upper collimator plane, distance z{sub 2} above the lower collimator plane, and distance z{sub 3} above the plane of the detector array. The object to be X-rayed is located between the upper and lower collimator planes. The upper and lower collimators and the detector array are moved horizontally with scanning velocities v{sub 1}, v{sub 2}, v{sub 3} proportional to z{sub 1}, z{sub 2} and z{sub 3}, respectively. The pattern and size of openings in the collimators, and between detector positions is proportional such that similar triangles are always defined relative to the location of the X-ray source. X-rays that pass through openings in the upper collimator will always pass through corresponding and similar openings in the lower collimator, and thence to a corresponding detector in the underlying detector array. Substantially 100% of the X-rays irradiating the object (and neither absorbed nor scattered) pass through the lower collimator openings and are detected, which promotes enhanced sensitivity. A computer system coordinates repositioning of the collimators and detector array, and X-ray source locations. The computer system can store detector array output, and can associate a known X-ray source location with detector array output data, to provide three-dimensional imaging. Detector output may be viewed instantly, stored digitally, and/or transmitted electronically for image viewing at a remote site. 5 figs.
Parker, Sherwood
1995-01-01
A filmless X-ray imaging system includes at least one X-ray source, upper and lower collimators, and a solid-state detector array, and can provide three-dimensional imaging capability. The X-ray source plane is distance z.sub.1 above upper collimator plane, distance z.sub.2 above the lower collimator plane, and distance z.sub.3 above the plane of the detector array. The object to be X-rayed is located between the upper and lower collimator planes. The upper and lower collimators and the detector array are moved horizontally with scanning velocities v.sub.1, v.sub.2, v.sub.3 proportional to z.sub.1, z.sub.2 and z.sub.3, respectively. The pattern and size of openings in the collimators, and between detector positions is proportional such that similar triangles are always defined relative to the location of the X-ray source. X-rays that pass through openings in the upper collimator will always pass through corresponding and similar openings in the lower collimator, and thence to a corresponding detector in the underlying detector array. Substantially 100% of the X-rays irradiating the object (and neither absorbed nor scattered) pass through the lower collimator openings and are detected, which promotes enhanced sensitivity. A computer system coordinates repositioning of the collimators and detector array, and X-ray source locations. The computer system can store detector array output, and can associate a known X-ray source location with detector array output data, to provide three-dimensional imaging. Detector output may be viewed instantly, stored digitally, and/or transmitted electronically for image viewing at a remote site.
Wang, J.; Biasca, R.; Liewer, P.C.
1996-01-01
Although the existence of the critical ionization velocity (CIV) is known from laboratory experiments, no agreement has been reached as to whether CIV exists in the natural space environment. In this paper the authors move towards more realistic models of CIV and present the first fully three-dimensional, electromagnetic particle-in-cell Monte-Carlo collision (PIC-MCC) simulations of typical space-based CIV experiments. In their model, the released neutral gas is taken to be a spherical cloud traveling across a magnetized ambient plasma. Simulations are performed for neutral clouds with various sizes and densities. The effects of the cloud parameters on ionization yield, wave energy growth, electron heating, momentum coupling, and the three-dimensional structure of the newly ionized plasma are discussed. The simulations suggest that the quantitative characteristics of momentum transfers among the ion beam, neutral cloud, and plasma waves is the key indicator of whether CIV can occur in space. The missing factors in space-based CIV experiments may be the conditions necessary for a continuous enhancement of the beam ion momentum. For a typical shaped charge release experiment, favorable CIV conditions may exist only in a very narrow, intermediate spatial region some distance from the release point due to the effects of the cloud density and size. When CIV does occur, the newly ionized plasma from the cloud forms a very complex structure due to the combined forces from the geomagnetic field, the motion induced emf, and the polarization. Hence the detection of CIV also critically depends on the sensor location. 32 refs., 8 figs., 2 tabs.
Makedonska, Nataliia; Painter, Scott L.; Bui, Quan M.; Gable, Carl W.; Karra, Satish
2015-09-16
The discrete fracture network (DFN) model is a method to mimic discrete pathways for fluid flow through a fractured low-permeable rock mass, and may be combined with particle tracking simulations to address solute transport. However, experience has shown that it is challenging to obtain accurate transport results in three-dimensional DFNs because of the high computational burden and difficulty in constructing a high-quality unstructured computational mesh on simulated fractures. We present a new particle tracking capability, which is adapted to control volume (Voronoi polygons) flow solutions on unstructured grids (Delaunay triangulations) on three-dimensional DFNs. The locally mass-conserving finite-volume approach eliminates mass balance-related problems during particle tracking. The scalar fluxes calculated for each control volume face by the flow solver are used to reconstruct a Darcy velocity at each control volume centroid. The groundwater velocities can then be continuously interpolated to any point in the domain of interest. The control volumes at fracture intersections are split into four pieces, and the velocity is reconstructed independently on each piece, which results in multiple groundwater velocities at the intersection, one for each fracture on each side of the intersection line. This technique enables detailed particle transport representation through a complex DFN structure. Verified for small DFNs, the new simulation capability enables numerical experiments on advective transport in large DFNs to be performed. As a result, we demonstrate this particle transport approach on a DFN model using parameters similar to those of crystalline rock at a proposed geologic repository for spent nuclear fuel in Forsmark, Sweden.
Office of Scientific and Technical Information (OSTI)
... Li and Chouteau (1998) present a comprehensive history of the different derivations of ... advantage of an unbiased model assessment in the presence of uncertain prior information. ...
Office of Scientific and Technical Information (OSTI)
... Gravimetric analysis of uniform polyhedra: Geo- physics, 61, 357-364. Holstein, H., P. ... (Erratum in GEO-54-9-1213-1213; Discussion in GEO-54-9-1213-1213 with reply by author). ...
Warren, Oden Lee; Asif, Syed Amanulla Syed; Oh, Yunje; Feng, Yuxin; Cyrankowski, Edward; Major, Ryan
2014-09-30
A testing instrument for mechanical testing at nano or micron scale includes a transducer body, and a coupling shaft coupled with a probe tip. A transducer body houses a capacitor. The capacitor includes first and second counter electrodes and a center electrode assembly interposed therebetween. The center electrode assembly is movable with the coupling shaft relative to the first and second counter electrodes, for instance in one or more of dimensions including laterally and normally. The center electrode assembly includes a center plate coupled with the coupling shaft and one or more springs extending from the center plate. Upper and lower plates are coupled with the center plate and cover the center plate and the one or more springs. A shaft support assembly includes one or more support elements coupled along the coupling shaft. The shaft support assembly provides lateral support to the coupling shaft.
Tsai, Shang-Min; Gu, Pin-Gao; Dobbs-Dixon, Ian
2014-10-01
Three-dimensional (3D) equatorial trapped waves excited by stellar isolation and the resulting equatorial super-rotating jet in a vertical stratified atmosphere of a tidally locked hot Jupiter are investigated. Taking the hot Jupiter HD 189733b as a fiducial example, we analytically solve linear equations subject to stationary stellar heating with a uniform zonal-mean flow included. We also extract wave information in the final equilibrium state of the atmosphere from our radiative hydrodynamical simulation for HD 189733b. Our analytic wave solutions are able to qualitatively explain the 3D simulation results. Apart from previous wave studies, investigating the vertical structure of waves allows us to explore new wave features such as the wavefronts tilts related to the Rossby-wave resonance as well as dispersive equatorial waves. We also attempt to apply our linear wave analysis to explain some numerical features associated with the equatorial jet development seen in the general circulation model by Showman and Polvani. During the spin-up phase of the equatorial jet, the acceleration of the jet can be in principle boosted by the Rossby-wave resonance. However, we also find that as the jet speed increases, the Rossby-wave structure shifts eastward, while the Kelvin-wave structure remains approximately stationary, leading to the decline of the acceleration rate. Our analytic model of jet evolution implies that there exists only one stable equilibrium state of the atmosphere, possibly implying that the final state of the atmosphere is independent of initial conditions in the linear regime. Limitations of our linear model and future improvements are also discussed.
Lehmann, G.; Spatschek, K. H.
2014-05-15
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.
Poomvises, Watanachak; Zhang Jie; Olmedo, Oscar
2010-07-10
We report on several new findings regarding the kinematic and morphological evolution of coronal mass ejections (CMEs) in the inner heliosphere using the unprecedented STEREO/SECCHI observations. The CME tracking is based on the three-dimensional Raytrace model, which is free of the projection effect, resulting in true CME velocities. We also measure the cross section size of the CME and hence its expansion velocity. For the four major CME events investigated, we find that their leading edge (LE) velocity converges from an initial range between 400 km s{sup -1} and 1500 km s{sup -1} at 5-10 R{sub sun} to a narrow range between 500 km s{sup -1} and 750 km s{sup -1} at 50 R{sub sun}. The expansion velocity is also found to converge into a narrow range between 75 km s{sup -1} and 175 km s{sup -1}. Both LE and expansion velocities are nearly constant after 50 R{sub sun}. We further find that the acceleration of CMEs in the inner heliosphere from {approx}10 to 90 R{sub sun} can be described by an exponential function, with an initial value as large as {approx}-80 m s{sup -2} but exponentially decreasing to almost zero (more precisely, less than {+-}5 m s{sup -2} considering the uncertainty of measurements). These results provide important observational constraints on understanding CME dynamics in interplanetary space.
Rodgers, Arthur J.; Dreger, Douglas S.; Pitarka, Arben
2015-06-15
We performed three-dimensional (3D) anelastic ground motion simulations of the South Napa earthquake to investigate the performance of different finite rupture models and the effects of 3D structure on the observed wavefield. We considered rupture models reported by Dreger et al. (2015), Ji et al., (2015), Wei et al. (2015) and Melgar et al. (2015). We used the SW4 anelastic finite difference code developed at Lawrence Livermore National Laboratory (Petersson and Sjogreen, 2013) and distributed by the Computational Infrastructure for Geodynamics. This code can compute the seismic response for fully 3D sub-surface models, including surface topography and linear anelasticity. We use the 3D geologic/seismic model of the San Francisco Bay Area developed by the United States Geological Survey (Aagaard et al., 2008, 2010). Evaluation of earlier versions of this model indicated that the structure can reproduce main features of observed waveforms from moderate earthquakes (Rodgers et al., 2008; Kim et al., 2010). Simulations were performed for a domain covering local distances (< 25 km) and resolution providing simulated ground motions valid to 1 Hz.
Peterson, J. L. Michel, P.; Thomas, C. A.; Town, R. P. J.
2014-07-15
Achieving symmetric hohlraum radiation drive is an important aspect of indirectly driven inertial confinement fusion experiments. However, when experimentally delivered laser powers deviate from ideal conditions, the resultant radiation field can become asymmetric. Two situations in which this may arise are random uncorrelated fluctuations, in as-delivered laser power and laser beams that do not participate in the implosion (either intentionally or unintentionally). Furthermore, laser plasma interactions in the hohlraum obfuscate the connection between laser powers and radiation drive. To study the effect of these situations on drive symmetry, we develop a simplified model for crossed-beam energy transfer, laser backscatter, and plasma absorption that can be used in conjunction with view factor calculations to expediently translate laser powers into three-dimensional capsule flux symmetries. We find that crossed-beam energy transfer can alter both the statistical properties of uncorrelated laser fluctuations and the impact of missing laser beams on radiation symmetry. A method is proposed to mitigate the effects of missing laser beams.
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)
2014-05-10
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.
Ding, Y.H., E-mail: yhding@xtu.edu.cn [College of Chemical Engineering, Xiangtan University, Hunan 411105 (China); Institute of Rheology Mechanics, Xiangtan University, Hunan 411105 (China); Ren, H.M. [Institute of Rheology Mechanics, Xiangtan University, Hunan 411105 (China); Huang, Y.Y. [BTR New Energy Materials Inc., Shenzhen 518000 (China); Chang, F.H.; Zhang, P. [Institute of Rheology Mechanics, Xiangtan University, Hunan 411105 (China)
2013-10-15
Graphical abstract: Graphene/LiFePO{sub 4} composites as a high-performance cathode material for flexible lithium-ion batteries have been prepared by using a co-precipitation method to synthesize graphene/LiFePO4 powders as precursors and then followed by a solvent evaporation process. - Highlights: • Flexible LiFePO{sub 4}/graphene films were prepared first time by a solvent evaporation process. • The flexible electrode exhibited a high discharge capacity without conductive additives. • Graphene network offers the electrode adequate strength to withstand repeated flexing. - Abstract: Three-dimensional graphene/LiFePO{sub 4} nanostructures for flexible lithium-ion batteries were successfully prepared by solvent evaporation method. Structural characteristics of flexible electrodes were investigated by X-ray diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscopy (SEM). Electrochemical performance of graphene/LiFePO{sub 4} was examined by a variety of electrochemical testing techniques. The graphene/LiFePO{sub 4} nanostructures showed high electrochemical properties and significant flexibility. The composites with low graphene content exhibited a high capacity of 163.7 mAh g{sup ?1} at 0.1 C and 114 mAh g{sup ?1} at 5 C without further incorporation of conductive agents.
Kuznetsov, Alexey A.; Nita, Gelu M.; Fleishman, Gregory D.
2011-12-01
Microwave emission of solar flares is formed primarily by incoherent gyrosynchrotron radiation generated by accelerated electrons in coronal magnetic loops. The resulting emission depends on many factors, including pitch-angle distribution of the emitting electrons and the source geometry. In this work, we perform systematic simulations of solar microwave emission using recently developed tools (GS Simulator and fast gyrosynchrotron codes) capable of simulating maps of radio brightness and polarization as well as spatially resolved emission spectra. A three-dimensional model of a symmetric dipole magnetic loop is used. We compare the emission from isotropic and anisotropic (of loss-cone type) electron distributions. We also investigate effects caused by inhomogeneous distribution of the emitting particles along the loop. It is found that the effect of the adopted moderate electron anisotropy is the most pronounced near the footpoints and it also depends strongly on the loop orientation. Concentration of the emitting particles at the looptop results in a corresponding spatial shift of the radio brightness peak, thus reducing effects of the anisotropy. The high-frequency ({approx}> 50 GHz) emission spectral index is specified mainly by the energy spectrum of the emitting electrons; however, at intermediate frequencies (around 10-20 GHz), the spectrum shape is strongly dependent on the electron anisotropy, spatial distribution, and magnetic field nonuniformity. The implications of the obtained results for the diagnostics of the energetic electrons in solar flares are discussed.
Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham
2013-12-15
Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147–53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation to surrounding healthy tissue. A same-subject repeated measures design was used for this study, where five anal carcinoma cases at the Andrew Love Cancer Centre were selected. Conformal and IMRT plans were generated and dosimetric evaluations were performed. Each plan was prescribed a total of 54 Gray (Gy) over a course of 30 fractions to the primary site. The IMRT plans resulted in improved dosimetry to the planning target volume (PTV) and reduction in radiation to the critical structures (bladder, external genitalia and femoral heads). Statistically there was no difference between the IMRT and conformal plans in the dose to the small and large bowel; however, the bowel IMRT dose–volume histogram (DVH) doses were consistently lower. The IMRT plans were superior to the conformal plans with improved dose conformity and reduced radiation to the surrounding healthy tissue. Anecdotally it was found that patients tolerated the IMRT treatment better than the three-dimensional (3D) conformal radiation therapy. This study describes and compares the planning techniques.
MeshVoro: A Three-Dimensional Voronoi Mesh Building Tool for the TOUGH Family of Codes
Freeman, C. M.; Boyle, K. L.; Reagan, M.; Johnson, J.; Rycroft, C.; Moridis, G. J.
2013-09-30
Few tools exist for creating and visualizing complex three-dimensional simulation meshes, and these have limitations that restrict their application to particular geometries and circumstances. Mesh generation needs to trend toward ever more general applications. To that end, we have developed MeshVoro, a tool that is based on the Voro (Rycroft 2009) library and is capable of generating complex threedimensional Voronoi tessellation-based (unstructured) meshes for the solution of problems of flow and transport in subsurface geologic media that are addressed by the TOUGH (Pruess et al. 1999) family of codes. MeshVoro, which includes built-in data visualization routines, is a particularly useful tool because it extends the applicability of the TOUGH family of codes by enabling the scientifically robust and relatively easy discretization of systems with challenging 3D geometries. We describe several applications of MeshVoro. We illustrate the ability of the tool to straightforwardly transform a complex geological grid into a simulation mesh that conforms to the specifications of the TOUGH family of codes. We demonstrate how MeshVoro can describe complex system geometries with a relatively small number of grid blocks, and we construct meshes for geometries that would have been practically intractable with a standard Cartesian grid approach. We also discuss the limitations and appropriate applications of this new technology.
Mimouni, N.; Chikh, S.; Rahli, O.; Bennacer, R.
2014-07-15
Two-dimensional (2D) and three-dimensional (3D) numerical simulations of double diffusion natural convection in an elongated enclosure filled with a binary fluid saturating a porous medium are carried out in the present work. The Boussinesq approximation is made in the formulation of the problem, and Neumann boundary conditions for temperature and concentration are adopted, respectively, on vertical and horizontal walls of the cavity. The used numerical method is based on the control volume approach, with the third order quadratic upstream interpolation scheme in approximating the advection terms. A semi implicit method algorithm is used to handle the velocity-pressure coupling. To avoid the excessively high computer time inherent to the solution of 3D natural convection problems, full approximation storage with full multigrid method is used to solve the problem. A wide range of the controlling parameters (Rayleigh-Darcy number Ra, lateral aspect ratio Ay, Lewis number Le, and the buoyancy ration N) is investigated. We clearly show that increasing the depth of the cavity (i.e., the lateral aspect ratio) has an important effect on the flow patterns. The 2D perfect parallel flows obtained for small lateral aspect ratio are drastically destabilized by increasing the cavity lateral dimension. This yields a 3D fluid motion with a much more complex flow pattern and the usually considered 2D parallel flow model cannot be applied.
Nam,K.W.; Yang,X.
2009-03-01
Thin amorphous manganese oxide layers with a thickness of 3-5nm are electrodeposited on a carbon nanotube (CNT) film substrate that has a three-dimensional nanoporous structure (denoted asMnO2/CNT electrode). For the purpose of comparison, manganese oxide films are also electrodeposited on a flat Pt-coated Si wafer substrate (denoted as MnO2 film electrode). The pseudocapacitive properties of the MnO2 film and MnO2/CNT electrodes are examined in both aqueous electrolyte (1.0M KCl) and nonaqueousorganic electrolyte (1.0M LiClO4 in propylene carbonate). While both types of electrode showpseudocapacitive behaviour in the aqueous electrolyte, only the MnO2/CNT electrode does so in the organic electrolyte, due to its high oxide/electrolyte interfacial area and improved electron conduction through the CNT substrate. Compared with the MnO2 film electrode, the MnO2/CNT electrode shows a much higher specific capacitance and better high-rate capability, regardless of the electrolyte used.Use of the organic electrolyte results in a ?6 times higher specific energy compared with that obtained with the aqueous electrolyte, while maintaining a similar specific power. The construction of a threedimensional nanoporous network structure consisting of a thin oxide layer on a CNT film substrate at the nm scale and the use of an organic electrolyte are promising approaches to improving the specific energyof supercapacitors.
Hoover, C G; DeGroot, A J; Sherwood, R J
2000-06-01
ParaDyn is a parallel version of the DYNA3D computer program, a three-dimensional explicit finite-element program for analyzing the dynamic response of solids and structures. The ParaDyn program has been used as a production tool for over three years for analyzing problems which range in size from a few tens of thousands of elements to between one-million and ten-million elements. ParaDyn runs on parallel computers provided by the Department of Energy Accelerated Strategic Computing Initiative (ASCI) and the Department of Defense High Performance Computing and Modernization Program. Preprocessing and post-processing software utilities and tools are designed to facilitate the generation of partitioned domains for processors on a massively parallel computer and the visualization of both resultant data and boundary data generated in a parallel simulation. This manual provides a brief overview of the parallel implementation; describes techniques for running the ParaDyn program, tools and utilities; and provides examples of parallel simulations.
Whirley, R.G.
1991-05-01
This report is the User Manual for the 1991 version of DYNA3D, and also serves as an interim User Guide. DYNA3D is a nonlinear, explicit, finite element code for analyzing the transient dynamic response of three-dimensional solids and structures. The code is fully vectorized and is available on several computer platforms. DYNA3D includes solid, shell, beam, and truss elements to allow maximum flexibility in modeling physical problems. Many material models are available to represent a wide range of material behavior, including elasticity, plasticity, composites, thermal effects, and rate dependence. In addition, DYNA3D has a sophisticated contact interface capability, including frictional sliding and single surface contact. Rigid materials provide added modeling flexibility. A material model driver with interactive graphics display is incorporated into DYNA3D to permit accurate modeling of complex material response based on experimental data. Along with the DYNA3D Example Problem Manual, this document provides the information necessary to apply DYNA3D to solve a wide range of engineering analysis problems. 73 refs., 49 figs.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
R. Y. Chen; Gu, G. D.; Chen, Z. G.; Song, X. -Y.; Schneeloch, J. A.; Wang, F.; Wang, N. L.
2015-10-22
We present a magnetoinfrared spectroscopy study on a newly identified three-dimensional (3D) Dirac semimetal ZrTe5. We observe clear transitions between Landau levels and their further splitting under a magnetic field. Both the sequence of transitions and their field dependence follow quantitatively the relation expected for 3D massless Dirac fermions. The measurement also reveals an exceptionally low magnetic field needed to drive the compound into its quantum limit, demonstrating that ZrTe5 is an extremely clean system and ideal platform for studying 3D Dirac fermions. The splitting of the Landau levels provides direct, bulk spectroscopic evidence that a relatively weak magnetic fieldmoreÂ Â» can produce a sizable Zeeman effect on the 3D Dirac fermions, which lifts the spin degeneracy of Landau levels. As a result, our analysis indicates that the compound evolves from a Dirac semimetal into a topological line-node semimetal under the current magnetic field configuration.Â«Â less
Preliminary development of the LBL/USGS three-dimensional site-scale model of Yucca Mountain, Nevada
Wittwer, C.; Chen, G.; Bodvarsson, G.S.; Chornack, M.; Flint, A.; Flint, L.; Kwicklis, E.; Spengler, R.
1995-06-01
A 3-D model of moisture flow within the unsaturated zone at Yucca Mountain is being developed at LBL in cooperation with USGS. This site-scale model covers an area of about 34 km{sup 2} and is bounded by major faults to the north, east, and west. The relatively coarse-grid model includes about 300 horizontal grid-blocks and 17 layers. Contour maps and isopach maps are presented defining different types of infiltration zones, and the spatial distribution of Tiva Canyon, Paintbrush, and Topopah Spring hydrogeological units. Matrix flow is approximated using the van Genuchten model, and the equivalent continuum approximation is used to account for fracture flow in the welded units. One-, two-, and three-dimensional simulations are conducted using the TOUGH2 computer program. Steady-state simulations are performed with various uniform and nonuniform infiltration rates; results are interpreted in terms of effect of fault characteristics on moisture flow distribution, and on the location and formation of preferential pathways.
Mitchell, B.
1990-12-01
A one-dimensional radiative transfer model was used to compute the global radiative budget at the top of the atmosphere (TOA) and the surface for January and July. 1979. The model was also used to determine the global cloud radiative forcing for all clouds and for high and low cloud layers. In the computations. the authors used the monthly cloud data derived from the Air Force Three-Dimensional Cloud Nephanalysis (3DNEPH). These data were used in conjunction with conventional temperature and humidity profiles analyzed during the 1979 First GARP (Global Atmospheric Research Program) Global Experiment (FGGE) year. Global surface albedos were computed from available data and were included in the radiative transfer analysis. Comparisons of the model-produced outgoing solar and infrared fluxes with those derived from Nimbus 7 Earth Radiation Budget (ERS) data were made to validate the radiative model and cloud cover. For reflected solar and emitted infrared (IR) flux, differences within 20 w/sq m meters were shown.
Wielen, Gerard J. van der [Department of Radiation Oncology, Erasmus MC-Daniel den Hoed Cancer Center, Rotterdam (Netherlands)]. E-mail: g.vanderwielen@erasmusmc.nl; Putten, Wim van [Department of Biostatistics, Erasmus MC-Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Incrocci, Luca [Department of Radiation Oncology, Erasmus MC-Daniel den Hoed Cancer Center, Rotterdam (Netherlands)
2007-06-01
Purpose: The purpose of this study is to provide information about sexual function (SF) after three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer while taking important factors into account that influence SF. Methods and Materials: Between June 1997 and February 2003, a total of 268 patients from a randomized dose-escalation trial comparing 68 Gy and 78 Gy agreed to participate in an additional part of the trial that evaluated SF. Results: At baseline 28% of patients had erectile dysfunction (ED). After 1 year, 27% of the pretreatment potent patients had developed ED. After 2 years this percentage had increased to 36%. After 3 years it almost stabilized at 38%. Satisfaction with sexual life was significantly correlated with ED. After 2 years one third of the pre-treatment potent patients still had considerable to very much sexual desire and found sex (very) important. No significant differences were found between the two dose-arms. Potency aids were used on a regular base by 14% of the patients. Conclusion: By taking adjuvant hormonal therapy (HT), HT during follow-up and potency aids into account, we found a lower percentage of ED after 3D-CRT than reported in previous prospective studies. A large group of patients still had sexual desire, considered sex important and 14% used potency aids after 3D-CRT.
Bousbia-Salah, Anis; Vedovi, Juswald; D'Auria, Francesco; Ivanov, Kostadin; Galassi, Giorgio
2004-10-15
Thanks to continuous progress in computer technology, it is now possible to perform best-estimate simulations of complex scenarios in nuclear power plants. This method is carried out through the coupling of three-dimensional (3-D) neutron modeling of a reactor core into system codes. It is particularly appropriate for transients that involve strong interactions between core neutronics and reactor loop thermal hydraulics. For this purpose, the Peach Bottom boiling water reactor turbine trip test was selected to challenge the capability of such coupled codes. The test is characterized by a power excursion induced by rapid core pressurization and a self-limiting course behavior. In order to perform the closest simulation, the coupled thermal-hydraulic system code RELAP5 and 3-D neutron kinetic code PARCS were used. The obtained results are compared to those available from experimental data. Overall, the coupled code calculations globally predict the most significant observed aspects of the transient, such as the pressure wave amplitude across the core and the power course, with an acceptable agreement. However, sensitivity studies revealed that more-accurate code models should be considered in order to better match the void dynamic and the cross-section variations during transient conditions.
FAN-SHAPED JETS IN THREE-DIMENSIONAL RECONNECTION SIMULATION AS A MODEL OF UBIQUITOUS SOLAR JETS
Jiang Ronglin; Fang Cheng; Shibata, Kazunari; Isobe, Hiroaki
2011-01-10
Magnetic reconnection is a fundamental process in space and astrophysical plasmas in which the oppositely directed magnetic field changes its connectivity and eventually converts its energy into kinetic and thermal energy of the plasma. Recently, ubiquitous jets (for example, chromospheric anemone jets, penumbral microjets, umbral light bridge jets) have been observed by the Solar Optical Telescope on board the satellite Hinode. These tiny and frequently occurring jets are considered to be a possible evidence of small-scale ubiquitous reconnection in the solar atmosphere. However, the details of three-dimensional (3D) magnetic configuration are still not very clear. Here, we propose a new model based on 3D simulations of magnetic reconnection using a typical current sheet magnetic configuration with a strong guide field. The most interesting feature is that the jets produced by the reconnection eventually move along the guide field lines. This model provides a fresh understanding of newly discovered ubiquitous jets and moreover a new observational basis for the theory of astrophysical magnetic reconnection.
Ghatwary, Tamer M. H.; Patterson, Benjamin O.; Karthikesalingam, Alan; Hinchliffe, Robert J.; Loftus, Ian M.; Morgan, Robert; Thompson, Matt M.; Holt, Peter J. E.
2013-02-15
The morphology of infrarenal abdominal aortic aneurysms (AAAs) directly influences the perioperative outcome and long-term durability of endovascular aneurysm repair. A variety of methods have been proposed for the characterization of AAA morphology using reconstructed three-dimensional (3D) computed tomography (CT) images. At present, there is lack of consensus as to which of these methods is most applicable to clinical practice or research. The purpose of this review was to evaluate existing protocols that used 3D CT images in the assessment of various aspects of AAA morphology. An electronic search was performed, from January 1996 to the end of October 2010, using the Embase and Medline databases. The literature review conformed to PRISMA statement standards. The literature search identified 604 articles, of which 31 studies met inclusion criteria. Only 15 of 31 studies objectively assessed reproducibility. Existing published protocols were insufficient to define a single evidence-based methodology for preoperative assessment of AAA morphology. Further development and expert consensus are required to establish a standardized and validated protocol to determine precisely how morphology relates to outcomes after endovascular aneurysm repair.
Chang, S.L.; Lottes, S.A.; Petrick, M.
1994-06-01
A three-dimensional, two-phase, turbulent flow computer code was used to predict flow characteristics of seed particles and coal gas in the deswirl section of the CDIF MHD power train system. Seed material which has a great effect on the overall performance of the MHD system is injected in the deswirl against the swirling coal gas flow coming from the first stage combustor. While testing the MHD system, excessive seed material (70% more than theoretical value) was required to achieve design operating conditions. Calculations show that the swirling coal gas flow turns a 90 degree angle to minimize the swirl motion before entering a second stage combustor and many seed particles are too slow to react to the flow turning and deposit on the walls of the deswirl section. Some seed material deposited on the walls is covered by slag layer and removed from the gas flow. The reduction of seed material in the gas flow decreases MHD power generation significantly. A computational experiment was conducted and its results show that seed injection on the wall can be minimized by simply changing the seed injection and an optimum location was identified. If seed is injected from the location of choice, the seed deposition is reduced by a factor of 10 compared to the original case.
Deng, Zhiqun; Weiland, Mark A.; Fu, Tao; Seim, Thomas A.; Lamarche, Brian L.; Choi, Eric Y.; Carlson, Thomas J.; Eppard, Matthew B.
2011-05-26
In Part 1 of this paper [1], we presented the engineering design and instrumentation of the Juvenile Salmon Acoustic Telemetry System (JSATS) cabled system, a nonproprietary technology developed by the U.S. Army Corps of Engineers, Portland District, to meet the needs for monitoring the survival of juvenile salmonids through the 31 dams in the Federal Columbia River Power System. Here in Part 2, we describe how the JSATS cabled system was employed as a reference sensor network for detecting and tracking juvenile salmon. Time-of-arrival data for valid detections on four hydrophones were used to solve for the three-dimensional (3D) position of fish surgically implanted with JSATS acoustic transmitters. Validation tests demonstrated high accuracy of 3D tracking up to 100 m from the John Day Dam spillway. The along-dam component, used for assigning the route of fish passage, had the highest accuracy; the median errors ranged from 0.06 to 0.22 m, and root mean square errors ranged from 0.05 to 0.56 m at distances up to 100 m. For the case study at John Day Dam during 2008, the range for 3D tracking was more than 100 m upstream of the dam face where hydrophones were deployed, and detection and tracking probabilities of fish tagged with JSATS acoustic transmitters were higher than 98%. JSATS cabled systems have been successfully deployed on several major dams to acquire information for salmon protection and for development of more “fish-friendly” hydroelectric facilities.
Jens, Sjoerd; Lucatelli, Pierleone; Koelemay, Mark J. W.; Marquering, Henk A. Reekers, Jim A.
2013-06-15
Purpose. To evaluate the additional value of three-dimensional rotational angiography (3DRA) of the foot compared with digital subtraction angiography (DSA) in patients with critical limb ischemia (CLI). Technique. For 3DRA, the C-arm was placed in the propeller position with the foot in an isocentric position. The patient's unaffected foot was positioned in a footrest outside the field of view. For correct timing of 3DRA, the delay from contrast injection in the popliteal artery at the level of knee joint to complete pedal arterial enhancement was assessed using DSA. With this delay, 3DRA was started after injection of 15 ml contrast. Imaging of the 3DRA could directly be reconstructed and visualized.Materials and MethodsPatients undergoing 3DRA of the foot were prospectively registered. DSA and 3DRA images were scored separately for arterial patency and presence of collaterals. Treatment strategies were proposed based on DSA with and without the availability of 3DRA. Results. Eleven patients underwent 3DRA of the foot. One 3DRA was not included because the acquisition was focused on the heel instead of the entire foot. Diagnostic quality of 3DRA was good in all ten patients. 3DRA compared with DSA showed additional patent arteries in six patients, patent plantar arch in three patients, and collaterals between the pedal arteries in five patients. Additional information from 3DRA resulted in a change of treatment strategy in six patients. Conclusion, 3DRA of the foot contains valuable additional real-time information to better guide peripheral vascular interventions in patients with CLI and nonhealing tissue lesions.
Fu, Yong; Ji, Zhong; Ding, Wenzheng; Ye, Fanghao; Lou, Cunguang
2014-11-01
Purpose: Previous studies demonstrated that thermoacoustic imaging (TAI) has great potential for breast tumor detection. However, large field of view (FOV) imaging remains a long-standing challenge for three-dimensional (3D) breast tumor localization. Here, the authors propose a practical TAI system for noninvasive 3D localization of breast tumors with large FOV through the use of ultrashort microwave pulse (USMP). Methods: A USMP generator was employed for TAI. The energy density required for quality imaging and the corresponding microwave-to-acoustic conversion efficiency were compared with that of conventional TAI. The microwave energy distribution, imaging depth, resolution, and 3D imaging capabilities were then investigated. Finally, a breast phantom embedded with a laboratory-grown tumor was imaged to evaluate the FOV performance of the USMP TAI system, under a simulated clinical situation. Results: A radiation energy density equivalent to just 1.6%–2.2% of that for conventional submicrosecond microwave TAI was sufficient to obtain a thermoacoustic signal with the required signal-to-noise ratio. This result clearly demonstrated a significantly higher microwave-to-acoustic conversion efficiency of USMP TAI compared to that of conventional TAI. The USMP TAI system achieved 61 mm imaging depth and 12 × 12 cm{sup 2} microwave radiation area. The volumetric image of a copper target measured at depth of 4–6 cm matched well with the actual shape and the resolution reaches 230 ?m. The TAI of the breast phantom was precisely localized to an accuracy of 0.1 cm over an 8 × 8 cm{sup 2} FOV. Conclusions: The experimental results demonstrated that the USMP TAI system offered significant potential for noninvasive clinical detection and 3D localization of deep breast tumors, with low microwave radiation dose and high spatial resolution over a sufficiently large FOV.
Chitcholtan, Kenny; Asselin, Eric; Parent, Sophie; Sykes, Peter H.; Evans, John J.
2013-01-01
Three-dimensional (3D) in vitro models have an invaluable role in understanding the behaviour of tumour cells in a well defined microenvironment. This is because some aspects of tumour characteristics cannot be fully recapitulated in a cell monolayer (2D). In the present study, we compared growth patterns, expression of signalling molecules, and metabolism-associated proteins of endometrial cancer cell lines in 3D and 2D cell cultures. Cancer cells formed spherical structures in 3D reconstituted basement membrane (3D rBM), and the morphological appearance was cell line dependent. Cell differentiation was observed after 8 days in the 3D rBM. There was reduced proliferation, detected by less expression of PCNA in 3D rBM than in 2D cell monolayers. The addition of exogenous epidermal growth factor (EGF) to cancer cells induced phosphorylation of EGFR and Akt in both cell culture conditions. The uptake of glucose was selectively altered in the 3D rBM, but there was a lack of association with Glut-1 expression. The secretion of vascular endothelial growth factor (VEGF) and prostaglandin E{sub 2} (PGE{sub 2}) was selectively altered in 3D rBM, and it was cell line dependent. Our data demonstrated that 3D rBM as an in vitro model can influence proliferation and metabolism of endometrial cancer cell behaviour compared to 2D cell monolayer. Changes are specific to individual cell types. The use of 3D rBM is, therefore, important in the in vitro study of targeted anticancer therapies.
Liu, Chang; Deng, Na; Lee, Jeongwoo; Wang, Haimin; Wiegelmann, Thomas; Jiang, Chaowei; Dennis, Brian R.; Su, Yang; Donea, Alina
2014-11-10
We carry out a comprehensive investigation comparing the three-dimensional magnetic field restructuring, flare energy release, and the helioseismic response of two homologous flares, the 2011 September 6 X2.1 (FL1) and September 7 X1.8 (FL2) flares in NOAA AR 11283. In our analysis, (1) a twisted flux rope (FR) collapses onto the surface at a speed of 1.5 km s{sup â€“1} after a partial eruption in FL1. The FR then gradually grows to reach a higher altitude and collapses again at 3 km s{sup â€“1} after a fuller eruption in FL2. Also, FL2 shows a larger decrease of the flux-weighted centroid separation of opposite magnetic polarities and a greater change of the horizontal field on the surface. These imply a more violent coronal implosion with corresponding more intense surface signatures in FL2. (2) The FR is inclined northward and together with the ambient fields, it undergoes a southward turning after both events. This agrees with the asymmetric decay of the penumbra observed in the peripheral regions. (3) The amounts of free magnetic energy and nonthermal electron energy released during FL1 are comparable to those of FL2 within the uncertainties of the measurements. (4) No sunquake was detected in FL1; in contrast, FL2 produced two seismic emission sources S1 and S2 both lying in the penumbral regions. Interestingly, S1 and S2 are connected by magnetic loops, and the stronger source S2 has a weaker vertical magnetic field. We discuss these results in relation to the implosion process in the low corona and the sunquake generation.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Christov, Ivan C.; Lueptow, Richard M.; Ottino, Julio M.; Sturman, Rob
2014-05-22
We study three-dimensional (3D) chaotic dynamics through an analysis of transport in a granular flow in a half-full spherical tumbler rotated sequentially about two orthogonal axes (a bi-axial â€śblinkingâ€ť tumbler). The flow is essentially quasi-two-dimensional in any vertical slice of the sphere during rotation about a single axis, and we provide an explicit exact solution to the model in this case. Hence, the cross-sectional flow can be represented by a twist map, allowing us to express the 3D flow as a linked twist map (LTM). We prove that if the rates of rotation about each axis are equal, then (inmoreÂ Â» the absence of stochasticity) particle trajectories are restricted to two-dimensional (2D) surfaces consisting of a portion of a hemispherical shell closed by a â€ścap''; if the rotation rates are unequal, then particles can leave the surface they start on and traverse a volume of the tumbler. The period-one structures of the governing LTM are examined in detail: analytical expressions are provided for the location of period-one curves, their extent into the bulk of the granular material, and their dependence on the protocol parameters (rates and durations of rotations). Exploiting the restriction of trajectories to 2D surfaces in the case of equal rotation rates about the axes, a method is proposed for identifying and constructing 3D Kolmogorov--Arnold--Moser (KAM) tubes around the normally elliptic period-one curves. The invariant manifold structure arising from the normally hyperbolic period-one curves is also examined. When the motion is restricted to 2D surfaces, the structure of manifolds of the hyperbolic points in the bulk differs from that corresponding to hyperbolic points in the flowing layer. Each is reminiscent of a template provided by a non-integrable perturbation to a Hamiltonian system, though the governing LTM is not. This highlights the novel 3D chaotic behaviors observed in this model dynamical system.Â«Â less
Lanekoff, Ingela T.; Burnum-Johnson, Kristin E.; Thomas, Mathew; Cha, Jeeyeon; Dey, Sudhansu K.; yang, Pengxiang; Prieto, Mari; Laskin, Julia
2015-03-01
Abstract Three-dimensional (3D) imaging of tissue sections is a new frontier in mass spectrometry imaging (MSI). Here we report on fast 3D imaging of lipids and metabolites associated with mouse uterine decidual cells and embryo at the implantation site on day 6 of pregnancy. 2D imaging of 16-20 serial tissue sections deposited on the same glass slide was performed using nanospray desorption electrospray ionization (nano-DESI) – an ambient ionization technique that enables sensitive localized analysis of analytes on surfaces without special sample pre-treatment. In this proof-of-principle study, nano-DESI was coupled to a high-resolution Q-Exactive instrument operated at high repetition rate of >5 Hz with moderate mass resolution of 35,000 (m/?m at m/z 200), which enabled acquisition of the entire 3D image with a spatial resolution of ~150 ?m in less than 4.5 hours. The results demonstrate localization of acetylcholine in the primary decidual zone (PDZ) of the implantation site throughout the depth of the tissue examined, indicating an important role of this signaling molecule in decidualization. Choline and phosphocholine – metabolites associated with cell growth – are enhanced in the PDZ and abundant in other cellular regions of the implantation site. Very different 3D distributions were obtained for fatty acids (FA), oleic acid and linoleic acid (FA 18:1 and FA 18:2), differing only by one double bond. Localization of FA 18:2 in the PDZ indicates its important role in decidualization while FA 18:1 is distributed more evenly throughout the tissue. In contrast, several lysophosphatidylcholines (LPC) observed in this study show donut-like distributions with localization around the PDZ. Complementary distributions with minimal overlap were observed for LPC 18:0 and FA 18:2 while the 3D image of the potential precursor phosphatidylcholine (PC 36:2) showed a significant overlap with both LPC 18:0 and FA 18:2.
Christov, Ivan C.; Lueptow, Richard M.; Ottino, Julio M.; Sturman, Rob
2014-05-22
We study three-dimensional (3D) chaotic dynamics through an analysis of transport in a granular flow in a half-full spherical tumbler rotated sequentially about two orthogonal axes (a bi-axial “blinking” tumbler). The flow is essentially quasi-two-dimensional in any vertical slice of the sphere during rotation about a single axis, and we provide an explicit exact solution to the model in this case. Hence, the cross-sectional flow can be represented by a twist map, allowing us to express the 3D flow as a linked twist map (LTM). We prove that if the rates of rotation about each axis are equal, then (in the absence of stochasticity) particle trajectories are restricted to two-dimensional (2D) surfaces consisting of a portion of a hemispherical shell closed by a “cap''; if the rotation rates are unequal, then particles can leave the surface they start on and traverse a volume of the tumbler. The period-one structures of the governing LTM are examined in detail: analytical expressions are provided for the location of period-one curves, their extent into the bulk of the granular material, and their dependence on the protocol parameters (rates and durations of rotations). Exploiting the restriction of trajectories to 2D surfaces in the case of equal rotation rates about the axes, a method is proposed for identifying and constructing 3D Kolmogorov--Arnold--Moser (KAM) tubes around the normally elliptic period-one curves. The invariant manifold structure arising from the normally hyperbolic period-one curves is also examined. When the motion is restricted to 2D surfaces, the structure of manifolds of the hyperbolic points in the bulk differs from that corresponding to hyperbolic points in the flowing layer. Each is reminiscent of a template provided by a non-integrable perturbation to a Hamiltonian system, though the governing LTM is not. This highlights the novel 3D chaotic behaviors observed in this model dynamical system.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Finn, John M.
2015-03-01
Properties of integration schemes for solenoidal fields in three dimensions are studied, with a focus on integrating magnetic field lines in a plasma using adaptive time stepping. It is shown that implicit midpoint (IM) and a scheme we call three-dimensional leapfrog (LF) can do a good job (in the sense of preserving KAM tori) of integrating fields that are reversible, or (for LF) have a 'special divergence-free' property. We review the notion of a self-adjoint scheme, showing that such schemes are at least second order accurate and can always be formed by composing an arbitrary scheme with its adjoint. WemoreÂ Â» also review the concept of reversibility, showing that a reversible but not exactly volume-preserving scheme can lead to a fractal invariant measure in a chaotic region, although this property may not often be observable. We also show numerical results indicating that the IM and LF schemes can fail to preserve KAM tori when the reversibility property (and the SDF property for LF) of the field is broken. We discuss extensions to measure preserving flows, the integration of magnetic field lines in a plasma and the integration of rays for several plasma waves. The main new result of this paper relates to non-uniform time stepping for volume-preserving flows. We investigate two potential schemes, both based on the general method of Ref. [11], in which the flow is integrated in split time steps, each Hamiltonian in two dimensions. The first scheme is an extension of the method of extended phase space, a well-proven method of symplectic integration with non-uniform time steps. This method is found not to work, and an explanation is given. The second method investigated is a method based on transformation to canonical variables for the two split-step Hamiltonian systems. This method, which is related to the method of non-canonical generating functions of Ref. [35], appears to work very well.Â«Â less
Hirotani, Kouichi
2015-01-10
We investigate the particle accelerator that arises in a rotating neutron-star magnetosphere. Simultaneously solving the Poisson equation for the electro-static potential, the Boltzmann equations for relativistic electrons and positrons, and the radiative transfer equation, we demonstrate that the electric field is substantially screened along the magnetic field lines by pairs that are created and separated within the accelerator. As a result, the magnetic-field-aligned electric field is localized in higher altitudes near the light cylinder and efficiently accelerates the positrons created in the lower altitudes outward but does not accelerate the electrons inward. The resulting photon flux becomes predominantly outward, leading to typical double-peak light curves, which are commonly observed from many high-energy pulsars.
Temme, N.M.
1987-11-01
The analytical approach of Temme (1983 and 1985), based on uniform asymptotic expansions, is extended to an additional class of incomplete Laplace integrals. The terminology is introduced; the construction of the formal series is explained; representations for the remainders are derived; the asymptotic nature of the expansions is explored; and error bounds are determined. Numerical results are presented for the case of the incomplete beta function. 14 references.
Jouffret, Laurent; Shao Zhenmian
2010-10-15
Seven new uranyl vanadates with mono-protonated amine or tetramethylammonium used as structure directing cations, (C{sub 2}NH{sub 8}){sub 2{l_brace}}[(UO{sub 2})(H{sub 2}O)][(UO{sub 2})(VO{sub 4})]{sub 4{r_brace}}.H{sub 2}O (DMetU5V4) (C{sub 2}NH{sub 8}){l_brace}[(UO{sub 2})(H{sub 2}O){sub 2}][(UO{sub 2})(VO{sub 4})]{sub 3{r_brace}}.H{sub 2}O (DMetU4V3), (C{sub 5}NH{sub 6}){sub 2{l_brace}}[(UO{sub 2})(H{sub 2}O)][(UO{sub 2})(VO{sub 4})]{sub 4{r_brace}}.H{sub 2}O (PyrU5V4), (C{sub 3}NH{sub 10}){l_brace}[(UO{sub 2})(H{sub 2}O){sub 2}][(UO{sub 2})(VO{sub 4})]{sub 3{r_brace}}.H{sub 2}O (isoPrU4V3), (N(CH{sub 3}){sub 4}){l_brace}[(UO{sub 2})(H{sub 2}O){sub 2}][(UO{sub 2})(VO{sub 4})]{sub 3{r_brace}}.H{sub 2}O (TMetU4V3), (C{sub 6}NH{sub 14}){l_brace}[(UO{sub 2})(H{sub 2}O){sub 2}][(UO{sub 2})(VO{sub 4})]{sub 3{r_brace}}.H{sub 2}O (CHexU4V3), and (C{sub 4}NH{sub 12}){l_brace}[(UO{sub 2})(H{sub 2}O)][(UO{sub 2})(VO{sub 4})]{sub 3{r_brace}} (TButU4V3) were prepared from mild-hydrothermal reactions using dimethylamine, pyridine, isopropylamine, tetramethylammonium hydroxide, cyclohexylamine and tertiobutylamine, respectively, with uranyl nitrate and vanadium oxide in acidic medium. The structures were solved using single-crystal X-ray diffraction data. The compounds exhibit three-dimensional uranyl-vanadate inorganic frameworks built from uranophane-type uranyl-vanadate layers pillared by uranyl polyhedra with cavities in between occupied by protonated organic moieties. In the uranyl-vanadate layers the orientations of the vanadate tetrahedra give new geometrical isomers leading to unprecedented pillared systems and new inorganic frameworks with U/V=4/3. Crystallographic data: (DMetU5V4) orthorhombic, Cmc2{sub 1} space group, a=15.6276(4), b=14.1341(4), c=13.6040(4) A; (DMetU4V3) monoclinic, P2{sub 1}/n space group, a=10.2312(4), b=13.5661(7), c=17.5291(7) A, {beta}=96.966(2); (PyrU5V4), triclinic, P1 space group, a=9.6981(3), b=9.9966(2), c=10.5523(2) A, {alpha}=117.194(1), {beta}=113.551(1), {gamma}=92.216(1){sup o}; (isoPrU4V3) monoclinic, P2{sub 1}/n space group, a=10.3507(1), b=13.6500(2), c=17.3035(2) A, {beta}=97.551(1){sup o}; (TMetU4V3) orthorhombic, Pbca space group, a=17.1819(2), b=13.6931(1), c=21.4826(2) A; (CHexU4V3), triclinic P-1 space group, a=9.8273(6), b=11.0294(7), c=12.7506(8) A, {alpha}=98.461(3), {beta}=96.437(3), {gamma}=105.955(3){sup o}; (TButU4V3), monoclinic, P2{sub 1}/m space group, a=9.8048(4), b=17.4567(8), c=15.4820(6) A, {beta}=106.103(2). - Graphical abstract: The various type of PBP pillars P2, P3, P4, and P4' in the three-dimensional inorganic frameworks based on the uranophane-type sheet in monoamine templated uranyl-vanadates.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Gao, Xujiao; Mamaluy, Denis; Mickel, Patrick R.; Marinella, Matthew
2015-09-08
In this paper, we present a fully-coupled electrical and thermal transport model for oxide memristors that solves simultaneously the time-dependent continuity equations for all relevant carriers, together with the time-dependent heat equation including Joule heating sources. The model captures all the important processes that drive memristive switching and is applicable to simulate switching behavior in a wide range of oxide memristors. The model is applied to simulate the ON switching in a 3D filamentary TaOx memristor. Simulation results show that, for uniform vacancy density in the OFF state, vacancies fill in the conduction filament till saturation, and then fill outmoreÂ Â» a gap formed in the Ta electrode during ON switching; furthermore, ON-switching time strongly depends on applied voltage and the ON-to-OFF current ratio is sensitive to the filament vacancy density in the OFF state.Â«Â less
Gao, Xujiao; Mamaluy, Denis; Mickel, Patrick R.; Marinella, Matthew
2015-09-08
In this paper, we present a fully-coupled electrical and thermal transport model for oxide memristors that solves simultaneously the time-dependent continuity equations for all relevant carriers, together with the time-dependent heat equation including Joule heating sources. The model captures all the important processes that drive memristive switching and is applicable to simulate switching behavior in a wide range of oxide memristors. The model is applied to simulate the ON switching in a 3D filamentary TaOx memristor. Simulation results show that, for uniform vacancy density in the OFF state, vacancies fill in the conduction filament till saturation, and then fill out a gap formed in the Ta electrode during ON switching; furthermore, ON-switching time strongly depends on applied voltage and the ON-to-OFF current ratio is sensitive to the filament vacancy density in the OFF state.
Bryan, W. A.; Newell, W. R.; Sanderson, J. H.; Langley, A. J. [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Department of Physics, University of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada); Central Laser Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX (United Kingdom)
2006-11-15
The two- and three-body Coulomb explosion of carbonyl sulfide (OCS) by 790 nm, 50 fs laser pulses focused to {approx_equal}10{sup 16} W cm{sup -2} has been investigated by the three-dimensional covariance mapping technique. In a triatomic molecule, a single charge state, in this case the trication, has been observed to dissociate into two distinct energy channels. With the aid of a three-dimensional visualization technique to reveal the ionization hierarchy, evidence is presented for the existence of two sets of ionization pathways resulting from these two initial states. While one group of ions can be modeled using a classical enhanced ionization model, the second group, consisting of mainly asymmetric channels, cannot. The results provide clear evidence that an enhanced ionization approach must also be accompanied by an appreciation of the effects of excited ionic states and multielectronic processes.
Ohsuka, Shinji; Ohba, Akira; Onoda, Shinobu; Nakamoto, Katsuhiro; Nakano, Tomoyasu; Miyoshi, Motosuke; Soda, Keita; Hamakubo, Takao
2014-09-15
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 KÎ± 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-ÎĽm scale three-dimensional fine structures were resolved.
Vu, Cung; Nihei, Kurt T.; Schmitt, Denis P.; Skelt, Christopher; Johnson, Paul A.; Guyer, Robert; TenCate, James A.; Le Bas, Pierre-Yves
2013-01-01
In some aspects of the disclosure, a method for creating three-dimensional images of non-linear properties and the compressional to shear velocity ratio in a region remote from a borehole using a conveyed logging tool is disclosed. In some aspects, the method includes arranging a first source in the borehole and generating a steered beam of elastic energy at a first frequency; arranging a second source in the borehole and generating a steerable beam of elastic energy at a second frequency, such that the steerable beam at the first frequency and the steerable beam at the second frequency intercept at a location away from the borehole; receiving at the borehole by a sensor a third elastic wave, created by a three wave mixing process, with a frequency equal to a difference between the first and second frequencies and a direction of propagation towards the borehole; determining a location of a three wave mixing region based on the arrangement of the first and second sources and on properties of the third wave signal; and creating three-dimensional images of the non-linear properties using data recorded by repeating the generating, receiving and determining at a plurality of azimuths, inclinations and longitudinal locations within the borehole. The method is additionally used to generate three dimensional images of the ratio of compressional to shear acoustic velocity of the same volume surrounding the borehole.
Farzad Rahnema
2009-11-12
This project has resulted in a highly efficient method that has been shown to provide accurate solutions to a variety of 2D and 3D reactor problems. The goal of this project was to develop (1) an accurate and efficient three-dimensional whole-core neutronics method with the following features: based sollely on transport theory, does not require the use of cross-section homogenization, contains a highly accurate and self-consistent global flux reconstruction procedure, and is applicable to large, heterogeneous reactor models, and to (2) create new numerical benchmark problems for code cross-comparison.
A high-order vertex-based central ENO finite-volume scheme for three-dimensional compressible flows
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Charest, Marc R.J.; Canfield, Thomas R.; Morgan, Nathaniel R.; Waltz, Jacob; Wohlbier, John G.
2015-03-11
High-order discretization methods offer the potential to reduce the computational cost associated with modeling compressible flows. However, it is difficult to obtain accurate high-order discretizations of conservation laws that do not produce spurious oscillations near discontinuities, especially on multi-dimensional unstructured meshes. A novel, high-order, central essentially non-oscillatory (CENO) finite-volume method that does not have these difficulties is proposed for tetrahedral meshes. The proposed unstructured method is vertex-based, which differs from existing cell-based CENO formulations, and uses a hybrid reconstruction procedure that switches between two different solution representations. It applies a high-order k-exact reconstruction in smooth regions and a limited linearmoreÂ Â» reconstruction when discontinuities are encountered. Both reconstructions use a single, central stencil for all variables, making the application of CENO to arbitrary unstructured meshes relatively straightforward. The new approach was applied to the conservation equations governing compressible flows and assessed in terms of accuracy and computational cost. For all problems considered, which included various function reconstructions and idealized flows, CENO demonstrated excellent reliability and robustness. Up to fifth-order accuracy was achieved in smooth regions and essentially non-oscillatory solutions were obtained near discontinuities. The high-order schemes were also more computationally efficient for high-accuracy solutions, i.e., they took less wall time than the lower-order schemes to achieve a desired level of error. In one particular case, it took a factor of 24 less wall-time to obtain a given level of error with the fourth-order CENO scheme than to obtain the same error with the second-order scheme.Â«Â less
Gascoyne, Andrew
2015-03-15
Using a full orbit test particle approach, we analyse the motion of a single proton in the vicinity of magnetic null point configurations which are solutions to the kinematic, steady state, resistive magnetohydrodynamics equations. We consider two magnetic configurations, namely, the sheared and torsional spine reconnection regimes [E. R. Priest and D. I. Pontin, Phys. Plasmas 16, 122101 (2009); P. Wyper and R. Jain, Phys. Plasmas 17, 092902 (2010)]; each produce an associated electric field and thus the possibility of accelerating charged particles to high energy levels, i.e.,â€‰>â€‰MeV, as observed in solar flares [R. P. Lin, Space Sci. Rev. 124, 233 (2006)]. The particle's energy gain is strongly dependent on the location of injection and is characterised by the angle of approach Î˛, with optimum angle of approach Î˛{sub opt} as the value of Î˛ which produces the maximum energy gain. We examine the topological features of each regime and analyse the effect on the energy gain of the proton. We also calculate the complete Lyapunov spectrum for the considered dynamical systems in order to correctly quantify the chaotic nature of the particle orbits. We find that the sheared model is a good candidate for the acceleration of particles, and for increased shear, we expect a larger population to be accelerated to higher energy levels. In the strong electric field regime (E{sub 0}=1500â€‰V/m), the torsional model produces chaotic particle orbits quantified by the calculation of multiple positive Lyapunov exponents in the spectrum, whereas the sheared model produces chaotic orbits only in the neighbourhood of the null point.
A high-order vertex-based central ENO finite-volume scheme for three-dimensional compressible flows
Charest, Marc R.J.; Canfield, Thomas R.; Morgan, Nathaniel R.; Waltz, Jacob; Wohlbier, John G.
2015-03-11
High-order discretization methods offer the potential to reduce the computational cost associated with modeling compressible flows. However, it is difficult to obtain accurate high-order discretizations of conservation laws that do not produce spurious oscillations near discontinuities, especially on multi-dimensional unstructured meshes. A novel, high-order, central essentially non-oscillatory (CENO) finite-volume method that does not have these difficulties is proposed for tetrahedral meshes. The proposed unstructured method is vertex-based, which differs from existing cell-based CENO formulations, and uses a hybrid reconstruction procedure that switches between two different solution representations. It applies a high-order k-exact reconstruction in smooth regions and a limited linear reconstruction when discontinuities are encountered. Both reconstructions use a single, central stencil for all variables, making the application of CENO to arbitrary unstructured meshes relatively straightforward. The new approach was applied to the conservation equations governing compressible flows and assessed in terms of accuracy and computational cost. For all problems considered, which included various function reconstructions and idealized flows, CENO demonstrated excellent reliability and robustness. Up to fifth-order accuracy was achieved in smooth regions and essentially non-oscillatory solutions were obtained near discontinuities. The high-order schemes were also more computationally efficient for high-accuracy solutions, i.e., they took less wall time than the lower-order schemes to achieve a desired level of error. In one particular case, it took a factor of 24 less wall-time to obtain a given level of error with the fourth-order CENO scheme than to obtain the same error with the second-order scheme.
Lohmann, R.C.
1992-01-01
Three-dimensional geologic outcrop studies which quantitatively describe the geologic architecture of deposits of a specific depositional environment are a necessary requirement for characterization of the permeability structure of an aquifer. The objective of this study is to address this need for quantitative, three-dimensional outcrop studies. For this study, a 10,000 m{sup 2} by 25 m high outcrop of Pliocene-Pleistocene Sierra Ladrones Formation located near Belen, New Mexico was mapped in detail, and the geologic architecture was quantified using geostatistical variogram analysis. In general, the information contained in this study should be useful for hydrologists working on the characterization of aquifers from similar depositional environments such as this one. However, for the permeability correlation study to be truly useful, the within-element correlation structure needs to be superimposed on the elements themselves instead of using mean log (k) values, as was done for this study. Such information is derived from outcrop permeability sampling such as the work of Davis (1990) and Goggin et al. (1988).
The fundamental solution of the unidirectional pulse propagation equation
Babushkin, I.; BergĂ©, L.
2014-03-15
The fundamental solution of a variant of the three-dimensional wave equation known as â€śunidirectional pulse propagation equationâ€ť (UPPE) and its paraxial approximation is obtained. It is shown that the fundamental solution can be presented as a projection of a fundamental solution of the wave equation to some functional subspace. We discuss the degree of equivalence of the UPPE and the wave equation in this respect. In particular, we show that the UPPE, in contrast to the common belief, describes wave propagation in both longitudinal and temporal directions, and, thereby, its fundamental solution possesses a non-causal character.
Canonical equations of ideal magnetic hydrodynamics
Gorskii, V.B.
1987-07-01
Ideal magnetohydrodynamics is used to consider a general class of adiabatic flow in magnetic liquids. Two invariants of the canonical equations of motion--Hamiltonian and Lagrangian--are determined in terms of the canonical variables by using the approximate variational formulations. The resulting model describes adiabatic three-dimensional flow of a nonviscous compressible liquid with ideal electric conductivity and zero heat conductivity. A Clebsch transformation is used to arrive at a form of the Lagrange-Cauchy integral for a vortex flow.
Gao Haiyong; Gao Puxian; Shimpi, Paresh; Guo Yanbing; Cai Wenjie; Lin Huijan; Staruch, M.; Jain, Menka
2011-03-21
Three-dimensional (3D) cubic perovskite (La,Sr)MnO{sub 3} (LSMO) nanofilms have been deposited on ZnO nanorod arrays with controlled dimensionality and crystallinity by radio frequency (rf) magnetron sputtering and post thermal annealing. Compared to the two-dimensional (2D) LSMO nanofilm on flat Si, the structure and magnetic properties of 3D LSMO nanofilms on ZnO nanorod arrays have a strong anisotropic morphology and thickness dependence. Ferromagnetic property has been observed in both 2D and 3D LSMO nanofilms while a ferromagnetic-superparamagnetic transition was revaled in 3D LSMO nanofilms on ZnO nanorod array with decreasing nanofilm thickness, due to a large surface dispersion effect. The LSMO/ZnO nanofilm/nanorod structures could open up new avenues for intriguing magnetic properties studies and applications of nanoscale perovskites.
R. Y. Chen; Gu, G. D.; Chen, Z. G.; Song, X. -Y.; Schneeloch, J. A.; Wang, F.; Wang, N. L.
2015-10-22
We present a magnetoinfrared spectroscopy study on a newly identified three-dimensional (3D) Dirac semimetal ZrTe_{5}. We observe clear transitions between Landau levels and their further splitting under a magnetic field. Both the sequence of transitions and their field dependence follow quantitatively the relation expected for 3D massless Dirac fermions. The measurement also reveals an exceptionally low magnetic field needed to drive the compound into its quantum limit, demonstrating that ZrTe_{5} is an extremely clean system and ideal platform for studying 3D Dirac fermions. The splitting of the Landau levels provides direct, bulk spectroscopic evidence that a relatively weak magnetic field can produce a sizable Zeeman effect on the 3D Dirac fermions, which lifts the spin degeneracy of Landau levels. As a result, our analysis indicates that the compound evolves from a Dirac semimetal into a topological line-node semimetal under the current magnetic field configuration.
p-doping-free InGaN/GaN light-emitting diode driven by three-dimensional hole gas
Zhang, Zi-Hui; Tiam Tan, Swee; Kyaw, Zabu; Liu, Wei; Ji, Yun; Ju, Zhengang; Zhang, Xueliang [LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore) [LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); Wei Sun, Xiao, E-mail: EXWSUN@ntu.edu.sg [LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); Department of Electronics and Electrical Engineering, South University of Science and Technology of China, Shenzhen, Guangdong 518055 (China); Volkan Demir, Hilmi, E-mail: VOLKAN@stanfordalumni.org [LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore (Singapore); Department of Electrical and Electronics, UNAM-Institute of Material Science and Nanotechnology, Bilkent University, Ankara TR-06800 (Turkey); Department of Physics, UNAM-Institute of Material Science and Nanotechnology, Bilkent University, Ankara TR-06800 (Turkey)
2013-12-23
Here, GaN/Al{sub x}Ga{sub 1-x}N heterostructures with a graded AlN composition, completely lacking external p-doping, are designed and grown using metal-organic-chemical-vapour deposition (MOCVD) system to realize three-dimensional hole gas (3DHG). The existence of the 3DHG is confirmed by capacitance-voltage measurements. Based on this design, a p-doping-free InGaN/GaN light-emitting diode (LED) driven by the 3DHG is proposed and grown using MOCVD. The electroluminescence, which is attributed to the radiative recombination of injected electrons and holes in InGaN/GaN quantum wells, is observed from the fabricated p-doping-free devices. These results suggest that the 3DHG can be an alternative hole source for InGaN/GaN LEDs besides common Mg dopants.
Zhang, Xing; Ibrahim, Yehia M.; Chen, Tsung-Chi; Kyle, Jennifer E.; Norheim, Randolph V.; Monroe, Matthew E.; Smith, Richard D.; Baker, Erin Shammel
2015-06-30
We report the first evaluation of a platform coupling a high speed field asymmetric ion mobility spectrometry microchip (µFAIMS) with drift tube ion mobility and mass spectrometry (IMS-MS). The µFAIMS/IMS-MS platform was used to analyze biological samples and simultaneously acquire multidimensional information of detected features from the measured FAIMS compensation fields and IMS drift times, while also obtaining accurate ion masses. These separations thereby increase the overall separation power, resulting increased information content, and provide more complete characterization of more complex samples. The separation conditions were optimized for sensitivity and resolving power by the selection of gas compositions and pressures in the FAIMS and IMS separation stages. The resulting performance provided three dimensional separations, benefitting both broad complex mixture studies and targeted analyses by e.g. improving isomeric separations and allowing detection of species obscured by “chemical noise” and other interfering peaks.
Zhang, Yijun; Cheng, Yang-Tse; Grummon, David S.
2007-03-01
Indentation-induced shape memory and superelastic effects are recently discovered thermo-mechanical behaviors that may find important applications in many areas of science and engineering. Theoretical understanding of these phenomena is challenging because both martensitic phase transformation and slip plasticity exist under complex contact loading conditions. In this paper, we develop a three-dimensional constitutive model of shape memory alloys with plasticity. Spherical indentation-induced superelasticity in a NiTi shape memory alloy was simulated and compared to experimental results on load-displacement curves and recovery ratios. We show that shallow indents have complete recovery upon unloading, where the size of the phase transformation region is about two times the contact radius. Deep indents have only partial recovery when plastic deformation becomes more prevalent in the indent-affected zone.
Hobbs, Robert F.; McNutt, Todd; Baechler, Sebastien; He Bin; Esaias, Caroline E.; Frey, Eric C.; Loeb, David M.; Wahl, Richard L.; Shokek, Ori; Sgouros, George
2011-07-15
Purpose: Effective cancer treatment generally requires combination therapy. The combination of external beam therapy (XRT) with radiopharmaceutical therapy (RPT) requires accurate three-dimensional dose calculations to avoid toxicity and evaluate efficacy. We have developed and tested a treatment planning method, using the patient-specific three-dimensional dosimetry package 3D-RD, for sequentially combined RPT/XRT therapy designed to limit toxicity to organs at risk. Methods and Materials: The biologic effective dose (BED) was used to translate voxelized RPT absorbed dose (D{sub RPT}) values into a normalized total dose (or equivalent 2-Gy-fraction XRT absorbed dose), NTD{sub RPT} map. The BED was calculated numerically using an algorithmic approach, which enabled a more accurate calculation of BED and NTD{sub RPT}. A treatment plan from the combined Samarium-153 and external beam was designed that would deliver a tumoricidal dose while delivering no more than 50 Gy of NTD{sub sum} to the spinal cord of a patient with a paraspinal tumor. Results: The average voxel NTD{sub RPT} to tumor from RPT was 22.6 Gy (range, 1-85 Gy); the maximum spinal cord voxel NTD{sub RPT} from RPT was 6.8 Gy. The combined therapy NTD{sub sum} to tumor was 71.5 Gy (range, 40-135 Gy) for a maximum voxel spinal cord NTD{sub sum} equal to the maximum tolerated dose of 50 Gy. Conclusions: A method that enables real-time treatment planning of combined RPT-XRT has been developed. By implementing a more generalized conversion between the dose values from the two modalities and an activity-based treatment of partial volume effects, the reliability of combination therapy treatment planning has been expanded.
Three-Dimensional Graphene Architectures
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Dimensional Graphene Architectures - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management
Three Dimensional Anodes and Architectures
Broader source: Energy.gov [DOE]
2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting
Timofeev, V. I.; Smirnova, E. A.; Chupova, L. A.; Esipov, R. S.; Kuranova, I. P.
2010-11-15
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).
Ehgartner, Brian L.; Sobolik, Steven Ronald; Bean, James E.
2010-07-01
The U.S. Strategic Petroleum Reserve stores crude oil in 62 solution-mined caverns in salt domes located in Texas and Louisiana. Historically, three-dimensional geomechanical simulations of the behavior of the caverns have been performed using a power law creep model. Using this method, and calibrating the creep coefficient to field data such as cavern closure and surface subsidence, has produced varying degrees of agreement with observed phenomena. However, as new salt dome locations are considered for oil storage facilities, pre-construction geomechanical analyses are required that need site-specific parameters developed from laboratory data obtained from core samples. The multi-mechanism deformation (M-D) model is a rigorous mathematical description of both transient and steady-state creep phenomena. Recent enhancements to the numerical integration algorithm within the model have created a more numerically stable implementation of the M-D model. This report presents computational analyses to compare the results of predictions of the geomechanical behavior at the West Hackberry SPR site using both models. The recently-published results using the power law creep model produced excellent agreement with an extensive set of field data. The M-D model results show similar agreement using parameters developed directly from laboratory data. It is also used to predict the behavior for the construction and operation of oil storage caverns at a new site, to identify potential problems before a final cavern layout is designed.
Hazari, Debdoot; Jana, Swapan Kumar; Fleck, Michel; Zangrando, Ennio; Dalai, Sudipta
2014-11-15
Two lead(II) compounds [Pb{sub 3}(idiac){sub 3}(phen){sub 2}(H{sub 2}O)]Â·2(H{sub 2}O) (1) and [Pb(ndc)]{sub n} (2), where H{sub 2}idiac=iminodiacetic acid, phen=1,10-phenanthroline and H{sub 2}ndc=naphthalene-2,6-dicarboxylic acid, have been synthesized and structurally characterized. Single crystal X-ray diffraction analysis showed that compound 1 is a discrete trinuclear complex (of two-fold symmetry) which evolves to a supramolecular 3D network via Ď€â€“Ď€ interactions, while in compound 2 the naphthalene dicarboxylate anion act as a linker to form a three dimensional architecture, where the anion adopts a bis-(bidentate bridging) coordination mode connecting four Pb(II) centers. The photoluminescence property of the two complexes has been studied. - graphical abstract: Two new topologically different 1D coordination polymers formed by Pb{sub 4} clusters have been synthesized and characterized by x-ray analysis. The luminescence and thermal properties have been studied. - Highlights: â€˘ 1 is a trinuclear complex of Pb(II) growing to 3D network via weak interactions. â€˘ In 1, layers of (4,4) rhomboidal topology are identified. â€˘ In 2, the ndc anion adopts interesting bis-(bidentate bridging) coordination. â€˘ In 2, network is reinforced by Câ€“Hâ€¦Ď€-ring interactions between the ndc rings.
Whirley, R.G.; Engelmann, B.E.
1993-11-01
This report is the User Manual for the 1993 version of DYNA3D, and also serves as a User Guide. DYNA3D is a nonlinear, explicit, finite element code for analyzing the transient dynamic response of three-dimensional solids and structures. The code is fully vectorized and is available on several computer platforms. DYNA3D includes solid, shell, beam, and truss elements to allow maximum flexibility in modeling physical problems. Many material models are available to represent a wide range of material behavior, including elasticity, plasticity, composites, thermal effects, and rate dependence. In addition, DYNA3D has a sophisticated contact interface capability, including frictional sliding and single surface contact. Rigid materials provide added modeling flexibility. A material model driver with interactive graphics display is incorporated into DYNA3D to permit accurate modeling of complex material response based on experimental data. Along with the DYNA3D Example Problem Manual, this document provides the information necessary to apply DYNA3D to solve a wide range of engineering analysis problems.
Jiang, Zhihang; Ma, Yongjun; Zhou, Yong; Hu, Shanglian; Han, Chaojiang; Pei, Chonghua
2013-10-15
Graphical abstract: - Highlights: • The Si/SiC composites were synthesized by one-step magnesiothermic reduction. • The mesoporous composites have a high specific surface area (655.7 m{sup 2} g{sup ?1}). • The composites exhibited a strong photoluminescence and better biocompatibility. • The mechanisms of formation and photoluminescence of sample were discussed. - Abstract: By converting modified silica aerogels to the corresponding silicon/silicon carbide (Si/SiC) without losing its nanostructure, three-dimensional mesoporous (3DM) Si/SiC composites are successfully synthesized via one-step magnesothermic reduction at relative low temperature (650 °C). The phase composition and microstructure of the resulting samples are measured by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), Raman spectra, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). N{sub 2}-sorption isotherms results show that the products have high Brunauer–Emmett–Teller (BET) specific surface areas (up to 656 m{sup 2} g{sup ?1}) and narrow pore-size distributions (1.5–30 nm). The composites exhibit a strong photoluminescence (PL) in blue-green light region (peak centered at 533 nm). We have set out work on the biocompatibility and enhancing PL of samples. As a result of excellent performances of the composites, it can be expected to have significant application in optoelectronics, biosensors, biological tracer and so on.
Boss, Alan P.; Keiser, Sandra A.
2014-06-10
A key test of the supernova triggering and injection hypothesis for the origin of the solar system's short-lived radioisotopes is to reproduce the inferred initial abundances of these isotopes. We present here the most detailed models to date of the shock wave triggering and injection process, where shock waves with varied properties strike fully three-dimensional, rotating, dense cloud cores. The models are calculated with the FLASH adaptive mesh hydrodynamics code. Three different outcomes can result: triggered collapse leading to fragmentation into a multiple protostar system; triggered collapse leading to a single protostar embedded in a protostellar disk; or failure to undergo dynamic collapse. Shock wave material is injected into the collapsing clouds through Rayleigh-Taylor fingers, resulting in initially inhomogeneous distributions in the protostars and protostellar disks. Cloud rotation about an axis aligned with the shock propagation direction does not increase the injection efficiency appreciably, as the shock parameters were chosen to be optimal for injection even in the absence of rotation. For a shock wave from a core-collapse supernova, the dilution factors for supernova material are in the range of ?10{sup –4} to ?3 × 10{sup –4}, in agreement with recent laboratory estimates of the required amount of dilution for {sup 60}Fe and {sup 26}Al. We conclude that a type II supernova remains as a promising candidate for synthesizing the solar system's short-lived radioisotopes shortly before their injection into the presolar cloud core by the supernova's remnant shock wave.
Rohatgi, U.S.; Cheng, H.S.; Khan, H.J.; Mallen, A.N.; Neymotin, L.Y.
1998-03-01
This document describes the major modifications and improvements made to the modeling of the RAMONA-3B/MOD0 code since 1981, when the code description and assessment report was completed. The new version of the code is RAMONA-4B. RAMONA-4B is a systems transient code for application to different versions of Boiling Water Reactors (BWR) such as the current BWR, the Advanced Boiling Water Reactor (ABWR), and the Simplified Boiling Water Reactor (SBWR). This code uses a three-dimensional neutron kinetics model coupled with a multichannel, non-equilibrium, drift-flux, two-phase flow formulation of the thermal hydraulics of the reactor vessel. The code is designed to analyze a wide spectrum of BWR core and system transients and instability issues. Chapter 1 is an overview of the code`s capabilities and limitations; Chapter 2 discusses the neutron kinetics modeling and the implementation of reactivity edits. Chapter 3 is an overview of the heat conduction calculations. Chapter 4 presents modifications to the thermal-hydraulics model of the vessel, recirculation loop, steam separators, boron transport, and SBWR specific components. Chapter 5 describes modeling of the plant control and safety systems. Chapter 6 presents and modeling of Balance of Plant (BOP). Chapter 7 describes the mechanistic containment model in the code. The content of this report is complementary to the RAMONA-3B code description and assessment document. 53 refs., 81 figs., 13 tabs.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Malek, Gary A.; Aytug, Tolga; Liu, Qingfeng; Wu, Judy
2015-04-02
Transparent nanostructured glass coatings, fabricated on glass substrates, with a unique three-dimensional (3D) architecture were utilized as the foundation for the design of plasmonic 3D transparent conductors. Transformation of the non-conducting 3D structure to a conducting 3D network was accomplished through atomic layer deposition of aluminum-doped zinc oxide (AZO). After AZO growth, gold nanoparticles (AuNPs) were deposited by electronbeam evaporation to enhance light trapping and decrease the overall sheet resistance. Field emission scanning electron microscopy and atomic force microcopy images revealed the highly porous, nanostructured morphology of the AZO coated glass surface along with the in-plane dimensions of the depositedmoreÂ Â» AuNPs. Sheet resistance measurements conducted on the coated samples verified that the electrical properties of the 3D network are comparable to that of the untextured two-dimensional AZO coated glass substrates. In addition, transmittance measurements of the glass samples coated with various AZO thicknesses showed preservation of the highly transparent nature of each sample, while the AuNPs demonstrated enhanced light scattering as well as light-trapping capability.Â«Â less
Ideal solar cell equation in the presence of photon recycling
Lan, Dongchen Green, Martin A.
2014-11-07
Previous derivations of the ideal solar cell equation based on Shockley's p-n junction diode theory implicitly assume negligible effects of photon recycling. This paper derives the equation in the presence of photon recycling that modifies the values of dark saturation and light-generated currents, using an approach applicable to arbitrary three-dimensional geometries with arbitrary doping profile and variable band gap. The work also corrects an error in previous work and proves the validity of the reciprocity theorem for charge collection in such a more general case with the previously neglected junction depletion region included.
Pevtsov, A. B. Grudinkin, S. A.; Poddubny, A. N.; Kaplan, S. F.; Kurdyukov, D. A.; Golubev, V. G.
2010-12-15
The parameters of three-dimensional photonic crystals based on opal-VO{sub 2} composite films in the 1.3-1.6 {mu}m spectral range important for practical applications (Telecom standard) are numerically calculated. For opal pores, the range of filling factors is established (0.25-0.6) wherein the composite exhibits the properties of a three-dimensional insulator photonic crystal. On the basis of the opal-VO{sub 2} composites, three-dimensional photonic film crystals are synthesized with specified parameters that provide a maximum shift of the photonic band gap in the vicinity of the wavelength {approx}1.5 {mu}m ({approx}170 meV) at the semiconductor-metal transition in VO{sub 2}.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Liu, Yong; Xing, Qingfeng; Straszheim, Warren E.; Marshman, Jeff; Pedersen, Pal; McLaughlin, Richard; Lograsso, Thomas A.
2016-02-11
Here, we report how the superconducting phase forms in pseudo-single-crystal KxFe2-ySe2. In situ scanning electron microscopy (SEM) observation reveals that, as an order-disorder transition occurs, on cooling, most of the high-temperature iron-vacancy-disordered phase gradually changes into the iron-vacancy-ordered phase whereas a small quantity of the high-temperature phase retains its structure and aggregates to the stripes with more iron concentration but less potassium concentration compared to the iron-vacancy-ordered phase. The stripes that are generally recognized as the superconducting phase are actually formed as a remnant of the high-temperature phase with a compositional change after an â€śimperfectâ€ť order-disorder transition. It should bemoreÂ Â» emphasized that the phase separation in pseudo-single-crystal KxFe2-ySe2 is caused by the iron-vacancy order-disorder transition. The shrinkage of the high-temperature phase and the expansion of the newly created iron-vacancy-ordered phase during the phase separation rule out the mechanism of spinodal decomposition proposed in an early report [Wang et al, Phys. Rev. B 91, 064513 (2015)]. Since the formation of the superconducting phase relies on the occurrence of the iron-vacancy order-disorder transition, it is impossible to synthesize a pure superconducting phase by a conventional solid state reaction or melt growth. By focused ion beam-scanning electron microscopy, we further demonstrate that the superconducting phase forms a contiguous three-dimensional architecture composed of parallelepipeds that have a coherent orientation relationship with the iron-vacancy-ordered phase.Â«Â less
Jiang, J.; Yuan, B.; Jin, M.; Wang, M.; Long, P.; Hu, L.
2012-07-01
Three-dimensional neutronics optimization calculations were performed to analyse the parameters of Tritium Breeding Ratio (TBR) and maximum average Power Density (PDmax) in a helium-cooled multi-functional experimental fusion-fission hybrid reactor named FDS (Fusion-Driven hybrid System)-MFX (Multi-Functional experimental) blanket. Three-stage tests will be carried out successively, in which the tritium breeding blanket, uranium-fueled blanket and spent-fuel-fueled blanket will be utilized respectively. In this contribution, the most significant and main goal of the FDS-MFX blanket is to achieve the PDmax of about 100 MW/m3 with self-sustaining tritium (TBR {>=} 1.05) based on the second-stage test with uranium-fueled blanket to check and validate the demonstrator reactor blanket relevant technologies based on the viable fusion and fission technologies. Four different enriched uranium materials were taken into account to evaluate PDmax in subcritical blanket: (i) natural uranium, (ii) 3.2% enriched uranium, (iii) 19.75% enriched uranium, and (iv) 64.4% enriched uranium carbide. These calculations and analyses were performed using a home-developed code VisualBUS and Hybrid Evaluated Nuclear Data Library (HENDL). The results showed that the performance of the blanket loaded with 64.4% enriched uranium was the most attractive and it could be promising to effectively obtain tritium self-sufficiency (TBR-1.05) and a high maximum average power density ({approx}100 MW/m{sup 3}) when the blanket was loaded with the mass of {sup 235}U about 1 ton. (authors)
Nam, Jin-Min; Onodera, Yasuhito; Bissell, Mina J; Park, Catherine C
2010-04-07
Tactics to selectively enhance cancer radioresponse are of great interest. Cancer cells actively elaborate and remodel their extracellular matrix (ECM) to aid in survival and progression. Previous work has shown that {beta}1-integrin inhibitory antibodies can enhance the growth-inhibitory and apoptotic responses of human breast cancer cell lines to ionizing radiation, either when cells are cultured in three-dimensional laminin-rich ECM (3D lrECM) or grown as xenografts in mice. Here, we show that a specific {alpha} heterodimer of {beta}1-integrin preferentially mediates a prosurvival signal in human breast cancer cells that can be specifically targeted for therapy. 3D lrECM culture conditions were used to compare {alpha}-integrin heterodimer expression in malignant and nonmalignant cell lines. Under these conditions, we found that expression of {alpha}5{beta}1-integrin was upregulated in malignant cells compared with nonmalignant breast cells. Similarly, we found that normal and oncofetal splice variants of fibronectin, the primary ECM ligand of {alpha}5{beta}1-integrin, were also strikingly upregulated in malignant cell lines compared with nonmalignant acini. Cell treatment with a peptide that disrupts the interactions of {alpha}5{beta}1-integrin with fibronectin promoted apoptosis in malignant cells and further heightened the apoptotic effects of radiation. In support of these results, an analysis of gene expression array data from breast cancer patients revealed an association of high levels of {alpha}5-integrin expression with decreased survival. Our findings offer preclinical validation of fibronectin and {alpha}5{beta}1-integrin as targets for breast cancer therapy.
Onishi, Yasuo; Kurikami, Hiroshi; Yokuda, Satoru T.
2014-03-28
After the accident at the Fukushima Daiichi Nuclear Power Plant in March 2011, the Japan Atomic Energy Agency and the Pacific Northwest National Laboratory initiated a collaborative project on environmental restoration. In October 2013, the collaborative team started a task of three-dimensional modeling of sediment and cesium transport in the Fukushima environment using the FLESCOT (Flow, Energy, Salinity, Sediment Contaminant Transport) code. As the first trial, we applied it to the Ogi Dam Reservoir that is one of the reservoirs in the Japan Atomic Energy Agencyâ€™s (JAEAâ€™s) investigation project. Three simulation cases under the following different temperature conditions were studied: â€˘ incoming rivers and the Ogi Dam Reservoir have the same water temperature â€˘ incoming rivers have lower water temperature than that of the reservoir â€˘ incoming rivers have higher water temperature than that of the reservoir. The preliminary simulations suggest that seasonal temperature changes influence the sediment and cesium transport. The preliminary results showed the following: â€˘ Suspended sand, and cesium adsorbed by sand, coming into the reservoirs from upstream rivers is deposited near the reservoir entrance. â€˘ Suspended silt, and cesium adsorbed by silt, is deposited farther in the reservoir. â€˘ Suspended clay, and cesium adsorbed by clay, travels the farthest into the reservoir. With sufficient time, the dissolved cesium reaches the downstream end of the reservoir. This preliminary modeling also suggests the possibility of a suitable dam operation to control the cesium migration farther downstream from the dam. JAEA has been sampling in the Ogi Dam Reservoir, but these data were not yet available for the current model calibration and validation for this reservoir. Nonetheless these preliminary FLESCOT modeling results were qualitatively valid and confirmed the applicability of the FLESCOT code to the Ogi Dam Reservoir, and in general to other reservoirs in the Fukushima environment. The issues to be addressed in future are the following: â€˘ Validate the simulation results by comparison with the investigation data. â€˘ Confirm the applicability of the FLESCOT code to Fukushima coastal areas. â€˘ Increase computation speed by parallelizing the FLESCOT code.
Kostadinova, Radina; Boess, Franziska; Suter, Laura; Weiser, Thomas; Singer, Thomas; Roth, Adrian
2013-04-01
Drug-induced liver injury (DILI) is the major cause for liver failure and post-marketing drug withdrawals. Due to species-specific differences in hepatocellular function, animal experiments to assess potential liabilities of drug candidates can predict hepatotoxicity in humans only to a certain extent. In addition to animal experimentation, primary hepatocytes from rat or human are widely used for pre-clinical safety assessment. However, as many toxic responses in vivo are mediated by a complex interplay among different cell types and often require chronic drug exposures, the predictive performance of hepatocytes is very limited. Here, we established and characterized human and rat in vitro three-dimensional (3D) liver co-culture systems containing primary parenchymal and non-parenchymal hepatic cells. Our data demonstrate that cells cultured on a 3D scaffold have a preserved composition of hepatocytes, stellate, Kupffer and endothelial cells and maintain liver function for up to 3 months, as measured by the production of albumin, fibrinogen, transferrin and urea. Additionally, 3D liver co-cultures maintain cytochrome P450 inducibility, form bile canaliculi-like structures and respond to inflammatory stimuli. Upon incubation with selected hepatotoxicants including drugs which have been shown to induce idiosyncratic toxicity, we demonstrated that this model better detected in vivo drug-induced toxicity, including species-specific drug effects, when compared to monolayer hepatocyte cultures. In conclusion, our results underline the importance of more complex and long lasting in vitro cell culture models that contain all liver cell types and allow repeated drug-treatments for detection of in vivo-relevant adverse drug effects. - Highlights: ? 3D liver co-cultures maintain liver specific functions for up to three months. ? Activities of Cytochrome P450s remain drug- inducible accross three months. ? 3D liver co-cultures recapitulate drug-induced liver toxicity observed in vivo. ? 3D liver co-cultures can detect species-specific drug toxicity observed in vivo. ? This in vitro model may improve assessment of human relevance of preclinical findings.
Tsien, Christina Moughan, Jennifer; Michalski, Jeff M.; Gilbert, Mark R.; Purdy, James; Simpson, Joseph; Kresel, John J.; Curran, Walter J.; Diaz, Aidnag; Mehta, Minesh P.
2009-03-01
Purpose: To evaluate in a Phase I trial the feasibility and toxicity of dose-escalated three-dimensional conformal radiotherapy (3D-CRT) concurrent with chemotherapy in patients with primary supratentorial glioblastoma (GBM). Methods and Materials: A total of 209 patients were enrolled. All received 46 Gy in 2-Gy fractions to the first planning target volume (PTV{sub 1}), defined as the gross tumor volume (GTV) plus 1.8 cm. A subsequent boost was given to PTV{sub 2}, defined as GTV plus 0.3 cm. Patients were stratified into two groups (Group 1: PTV{sub 2} <75 cm{sup 3}; Group 2: PTV{sub 2} {>=}75 cm{sup 3}). Four RT dose levels were evaluated: 66, 72, 78, and 84 Gy. Carmustine 80 mg/m{sup 2} was given during RT, then every 8 weeks for 6 cycles. Pretreatment characteristics were well balanced. Results: Acute and late Grade 3/4 RT-related toxicities were no more frequent at higher RT dose or with larger tumors. There were no dose-limiting toxicities (acute Grade {>=}3 irreversible central nervous system toxicities) observed on any dose level in either group. On the basis of the absence of dose-limiting toxicities, dose was escalated to 84 Gy in both groups. Late RT necrosis was noted at 66 Gy (1 patient), 72 Gy (2 patients), 78 Gy (2 patients), and 84 Gy (3 patients) in Group 1. In Group 2, late RT necrosis was noted at 78 Gy (1 patient) and 84 Gy (2 patients). Median time to RT necrosis was 8.8 months (range, 5.1-12.5 months). Median survival in Group 1 was 11.6-19.3 months. Median survival in Group 2 was 8.2-13.9 months. Conclusions: Our study shows the feasibility of delivering higher than standard (60 Gy) RT dose with concurrent chemotherapy for primary GBM, with an acceptable risk of late central nervous system toxicity.
Kim, Keun Su; Park, Jin Myung; Choi, Sooseok; Kim, Jongin; Hong, Sang Hee
2008-02-15
A comparative study between two- and three-dimensional (2D and 3D) modeling is carried out on arc discharge phenomena inside a thermal plasma torch with hollow electrodes, in order to evaluate the effects of arc root configuration characterized by either 2D annular or 3D highly localized attachment on the electrode surface. For this purpose, a more precise 3D transient model has been developed by taking account of 3D arc current distribution and arc root rotation. The 3D simulation results apparently reveal that the 3D arc root attachment brings about the inherent 3D and turbulence nature of plasma fields inside the torch. It is also found that the constricted arc column near the vortex chamber plays an important role in heating and acceleration of injected arc gases by concentrating arc currents on the axis of the hollow electrodes. The inherent 3D nature of arc discharge is well preserved inside the cathode region, while these 3D features slowly diminish behind the vortex chamber where the turbulent flow begins to be developed in the anode region. Based on the present simulation results, it is noted that the mixing effects of the strong turbulent flow on the heat and mass transfer are mainly responsible for the gradual relaxation of the 3D structures of plasma fields into the 2D axisymmetric ones that eventually appear in the anode region near the torch exit. From a detailed comparison of the 3D results with the 2D ones, the arc root configuration seems to have a significant effect on the heat transfer to the electrode surfaces interacting with the turbulent plasma flow. That is, in the 2D simulation based on an axisymmetric stationary model, the turbulence phenomena are fairly underestimated and the amount of heat transferred to the cold anode wall is calculated to be smaller than that obtained in the 3D simulation. For the validation of the numerical simulations, calculated plasma temperatures and axial velocities are compared with experimentally measured ones, and the 3D simulation turns out to be more accurate than the 2D simulation as a result of a relatively precise description of the turbulent phenomena inside the torch using a more realistic model of arc root attachment. Finally, it is suggested that the 3D transient formulation is indeed required for describing the real arc discharge phenomena inside the torch, while the 2D stationary approach is sometimes useful for getting practical information about the time-averaged plasma characteristics outside the torch because of its simplicity and rapidness in computation.
Takiwaki, Tomoya; Kotake, Kei; Suwa, Yudai
2012-04-20
We present numerical results on three-dimensional (3D) hydrodynamic core-collapse simulations of an 11.2 M{sub Sun} star. By comparing one-dimensional (1D) and two-dimensional (2D) results with those of 3D, we study how the increasing spacial multi-dimensionality affects the postbounce supernova dynamics. The calculations were performed with an energy-dependent treatment of the neutrino transport that is solved by the isotropic diffusion source approximation scheme. In agreement with previous study, our 1D model does not produce explosions for the 11.2 M{sub Sun} star, while the neutrino-driven revival of the stalled bounce shock is obtained in both the 2D and 3D models. The standing accretion-shock instability (SASI) is observed in the 3D models, in which the dominant mode of the SASI is bipolar (l = 2) with its saturation amplitudes being slightly smaller than 2D. By performing a tracer-particle analysis, we show that the maximum residency time of material in the gain region becomes longer in 3D than in 2D due to non-axisymmetric flow motions, which is one of advantageous aspects of 3D models to obtain neutrino-driven explosions. Our results show that convective matter motions below the gain radius become much more violent in 3D than in 2D, making the neutrino luminosity larger for 3D. Nevertheless, the emitted neutrino energies are made smaller due to the enhanced cooling. Our results indicate whether these advantages for driving 3D explosions could or could not overwhelm the disadvantages is sensitive to the employed numerical resolutions. An encouraging finding is that the shock expansion tends to become more energetic for models with finer resolutions. To draw a robust conclusion, 3D simulations with much higher numerical resolutions and with more advanced treatment of neutrino transport and of gravity are needed, which could be practicable by utilizing forthcoming Petaflops-class supercomputers.
A stochastic multi-symplectic scheme for stochastic Maxwell equations with additive noise
Hong, Jialin; Zhang, Liying
2014-07-01
In this paper we investigate a stochastic multi-symplectic method for stochastic Maxwell equations with additive noise. Based on the stochastic version of variational principle, we find a way to obtain the stochastic multi-symplectic structure of three-dimensional (3-D) stochastic Maxwell equations with additive noise. We propose a stochastic multi-symplectic scheme and show that it preserves the stochastic multi-symplectic conservation law and the local and global stochastic energy dissipative properties, which the equations themselves possess. Numerical experiments are performed to verify the numerical behaviors of the stochastic multi-symplectic scheme.
The one-dimensional Gross-Pitaevskii equation and its some excitation states
Prayitno, T. B.
2015-04-16
We have derived some excitation states of the one-dimensional Gross-Pitaevskii equation coupled by the gravitational potential. The methods that we have used here are taken by pursuing the recent work of Kivshar et. al. by considering the equation as a macroscopic quantum oscillator. To obtain the states, we have made the appropriate transformation to reduce the three-dimensional Gross-Pitaevskii equation into the one-dimensional Gross-Pitaevskii equation and applying the time-independent perturbation theory in the general solution of the one-dimensional Gross-Pitaevskii equation as a linear superposition of the normalized eigenfunctions of the SchrĂ¶dinger equation for the harmonic oscillator potential. Moreover, we also impose the condition by assuming that some terms in the equation should be so small in order to preserve the use of the perturbation method.
Sadybekov, Makhmud A.; Torebek, Berikbol T.; Turmetov, Batirkhan Kh.
2014-08-20
The paper is devoted to the investigation of questions about constructing the explicit form of the Green’s function of the Robin problem. For constructing this function we use the representation of the fundamental solution of the Laplace equation in the form of a series. An integral representation of the Green function is obtained and for some values of the parameters, the problem is presented in elementary functions.
Validity of ELTB Equation for Suitable Description of BEC
Kim, Dooyoung; Kim, Jinguanghao; Yoon, Jin-Hee
2005-10-17
The Bose-Einstein condensation (BEC) has been found for various alkali-metal gases such as 7Li, 87Rb, Na, and H. For the description of atoms in this condensate state, the Gross-Pitaevskii (GP) equation has been widely used. However, the GP equation contains the nonlinear term, which makes this equation hard to solve. Therefore, physical quantities are usually obtained numerically, and sometimes it is difficult to extract a physical meaning from the calculated results. The nuclear theory group at Purdue University in the U.S. developed a new simple equation, the equivalent linear two-body (ELTB) equation, using the hyper-radius coordinates and tested it for one-dimensional BEC system. Their results are consistent with the numerical values from the GP equation within 4.5%.We test the validity of the ELTB equation for three-dimensional BEC system by calculating the energies per particle and the wave functions for 87Rb gas and for 7Li gas. We use the quantum-mechanical variational method for the BEC energy. Our result for 87Rb gas agrees with a numerical calculation based on the GP equation, with a relative error of 12% over a wide range of N from 100 to 10,000. The relative distances between particles for 7Li gas are consistent within a relative error of 17% for N {<=} 1300. The relatively simple form of the ELTB equation, compared with the GP equation, enables us to treat the N-body system easily and efficiently. We conclude that the ELTB equation is a powerful equation for describing BEC system because it is easy to treat.
Chai Fang; Li Dongliu; Wu Hongbo; Zhang Chunli; Wang Xiaohong
2009-07-15
A three-dimensional ordered polyoxometalate periodic film was synthesized using dodecatungstophosphoric acid (H{sub 3}PW{sub 12}O{sub 40}) and Cs{sub 2}CO{sub 3} as precursors and colloidal crystals as templates by an inverse opal method. The samples were characterized by elemental analysis, XRD, IR spectra, UV-Vis diffuse reflectance spectra (DR-UV-Vis) and SEM techniques. This arrayed film constructed by pure cesium salt of dodecatungstophosphoric acid Cs{sub 2.5}H{sub 0.5}PW{sub 12}O{sub 40} nanoparticles shows well-defined lamellar array with inverse opal structure, which exhibits a well-defined photonic band gap. - Graphical abstract: A three-dimensional ordered Cs{sub 2.5}H{sub 0.5}PW{sub 12}O{sub 40} periodic film was synthesized by an inverse opal method using H{sub 3}PW{sub 12}O{sub 40} and Cs{sub 2}CO{sub 3} as precursors via nanocasting route and colloidal crystal as template (all scale bars are 1 {mu}m).
Plasmoid Instabilities Mediated Three-Dimensional Magnetohydrodynamic...
Office of Scientific and Technical Information (OSTI)
Exchanges Between Fluid and Kinetic Scales ; 2015-05-04 - 2015-05-06 ; Los Alamos, New Mexico, United States Research Org: Los Alamos National Laboratory (LANL) Sponsoring Org:...
Three-Dimensional Constrained Variational Analysis:
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
The analysisreanalysis data have larger biases at regional scale of a few hundred kilometers, and all analysesreanalyses tend to underestimate the subgrid- scale upward...
Three dimensional, multi-chip module
Bernhardt, A.F.; Petersen, R.W.
1993-08-31
A plurality of multi-chip modules are stacked and bonded around the perimeter by sold-bump bonds to adjacent modules on, for instance, three sides of the perimeter. The fourth side can be used for coolant distribution, for more interconnect structures, or other features, depending on particular design considerations of the chip set. The multi-chip modules comprise a circuit board, having a planarized interconnect structure formed on a first major surface, and integrated circuit chips bonded to the planarized interconnect surface. Around the periphery of each circuit board, long, narrow dummy chips'' are bonded to the finished circuit board to form a perimeter wall. The wall is higher than any of the chips on the circuit board, so that the flat back surface of the board above will only touch the perimeter wall. Module-to-module interconnect is laser-patterned on the sides of the boards and over the perimeter wall in the same way and at the same time that chip to board interconnect may be laser-patterned.
Three dimensional, multi-chip module
Bernhardt, Anthony F.; Petersen, Robert W.
1993-01-01
A plurality of multi-chip modules are stacked and bonded around the perimeter by sold-bump bonds to adjacent modules on, for instance, three sides of the perimeter. The fourth side can be used for coolant distribution, for more interconnect structures, or other features, depending on particular design considerations of the chip set. The multi-chip modules comprise a circuit board, having a planarized interconnect structure formed on a first major surface, and integrated circuit chips bonded to the planarized interconnect surface. Around the periphery of each circuit board, long, narrow "dummy chips" are bonded to the finished circuit board to form a perimeter wall. The wall is higher than any of the chips on the circuit board, so that the flat back surface of the board above will only touch the perimeter wall. Module-to-module interconnect is laser-patterned o the sides of the boards and over the perimeter wall in the same way and at the same time that chip to board interconnect may be laser-patterned.
Latin square three dimensional gage master
Jones, Lynn L.
1982-01-01
A gage master for coordinate measuring machines has an nxn array of objects distributed in the Z coordinate utilizing the concept of a Latin square experimental design. Using analysis of variance techniques, the invention may be used to identify sources of error in machine geometry and quantify machine accuracy.
Three dimensional microelectrode system for dielectrophoresis
Dehlinger, Dietrich A.; Rose, Klint A.; Shusteff, Maxim; Bailey, Christopher G.; Mariella, Jr., Raymond P.
2013-09-03
A dielectrophoresis apparatus for separating particles from a sample, including an apparatus body; a dielectrophoresis channel in the apparatus body, the dielectrophoresis channel having a central axis, a bottom, a top, a first side, and a second side; a first mesa projecting into the dielectrophoresis channel from the bottom and extending from the first side across the dielectrophoresis channel to the second side, the first mesa extending at an angle to the central axis of the dielectrophoresis channel; a first electrode extending along the first mesa; a second mesa projecting into the dielectrophoresis channel from the bottom and extending from the first side across the dielectrophoresis channel to the second side, the second mesa extending at an angle to the central axis of the dielectrophoresis channel; a space between at least one of the first electrode and the second side or the second electrode and the second side; and a gap between the first electrode and the second electrode.
Three dimensional characterization and archiving system
Clark, R.; Gallman, P.; Gaudreault, J.; Mosehauer, R.; Slotwinski, A.; Jarvis, G.; Griffiths, P.
1996-12-31
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.
Plasmoid Instabilities Mediated Three-Dimensional Magnetohydrodynamic...
Office of Scientific and Technical Information (OSTI)
National Technical Information Service, Springfield, VA at www.ntis.gov. Authors: Huang, Yi-min 1 ; Guo, Fan 2 + Show Author Affiliations Princeton University Los Alamos...
Three-dimensional scanning confocal laser microscope
Anderson, R. Rox; Webb, Robert H.; Rajadhyaksha, Milind
1999-01-01
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.
Hierarchical Three-Dimensional Microbattery Electrodes Combining...
Office of Scientific and Technical Information (OSTI)
Country of Publication: United States Language: English Subject: bio-inspired, energy storage (including batteries and capacitors), defects, charge transport, synthesis (novel ...
Three dimensional microelectrode system for dielectrophoresis (Patent) |
Office of Scientific and Technical Information (OSTI)
SciTech Connect apparatus for separating particles from a sample, including an apparatus body; a dielectrophoresis channel in the apparatus body, the dielectrophoresis channel having a central axis, a bottom, a top, a first side, and a second side; a first mesa projecting into the dielectrophoresis channel from the bottom and extending from the first side across the dielectrophoresis channel to the second side, the first mesa extending at an angle to the central axis of the dielectrophoresis
Three dimensional microelectrode system for dielectrophoresis (Patent) |
Office of Scientific and Technical Information (OSTI)
SciTech Connect method for separating particles from a sample, including a dielectrophoresis channel, the dielectrophoresis channel having a central axis, a bottom, a top, a first side, and a second side; a first mesa projecting into the dielectrophoresis channel from the bottom and extending from the first side across the dielectrophoresis channel to the second side, the first mesa extending at an angle to the central axis of the dielectrophoresis channel; a second mesa projecting into the
Three dimensional microelectrode system for dielectrophoresis...
Office of Scientific and Technical Information (OSTI)
a space between at least one of the first electrode and the second side or the second electrode and the second side; and a gap between the first electrode and the second electrode. ...
Three dimensional microelectrode system for dielectrophoresis...
Office of Scientific and Technical Information (OSTI)
electrode and the second side; and a gap between the first electrode and the second electrode, and pumping a recovery fluid through said gap between said first electrode and into ...
Three dimensional microelectrode system for dielectrophoresis
Dehlinger, Dietrich A; Rose, Klint A; Shusteff, Maxim; Bailey, Christopher G; Mariella, Jr., Raymond P
2014-12-02
A dielectrophoresis method for separating particles from a sample, including a dielectrophoresis channel, the dielectrophoresis channel having a central axis, a bottom, a top, a first side, and a second side; a first mesa projecting into the dielectrophoresis channel from the bottom and extending from the first side across the dielectrophoresis channel to the second side, the first mesa extending at an angle to the central axis of the dielectrophoresis channel; a second mesa projecting into the dielectrophoresis channel from the bottom and extending from the first side across the dielectrophoresis channel to the second side, the second mesa parallel to said first mesa; a space between at least one of the first electrode and the second side or the second electrode and the second side; and a gap between the first electrode and the second electrode, and pumping a recovery fluid through said gap between said first electrode and into said space between at least one of said first mesa and said second side or said second mesa and said second side.
Validation of a zero-equation turbulence model for complex indoor airflow simulation
Srebric, J.; Chen, Q.; Glicksman, L.R.
1999-07-01
The design of an indoor environment requires a tool that can quickly predict the three-dimensional distributions of air velocity, temperature, and contaminant concentrations in the room on a desktop computer. This investigation has tested a zero-equation turbulence model for the prediction of the indoor environment in an office with displacement ventilation, with a heater and infiltration and with forced convection and a partition wall. The computed air velocity and temperature distributions agree well with the measured data. The computing time for each case is less than seven minutes on a PC Pentium II, 350 MHz.
Kim, Min-Joo; Park, So-Hyun; Son, Seok-Hyun; Cheon, Keum-Seong; Choi, Byung-Ock; Suh, Tae-Suk
2013-10-01
The partial-breast irradiation (PBI) technique, an alternative to whole-breast irradiation, is a beam delivery method that uses a limited range of treatment volume. The present study was designed to determine the optimal PBI treatment modalities for 8 different tumor locations. Treatment planning was performed on computed tomography (CT) data sets of 6 patients who had received lumpectomy treatments. Tumor locations were classified into 8 subsections according to breast quadrant and depth. Three-dimensional conformal radiation therapy (3D-CRT), electron beam therapy (ET), and helical tomotherapy (H-TOMO) were utilized to evaluate the dosimetric effect for each tumor location. Conformation number (CN), radical dose homogeneity index (rDHI), and dose delivered to healthy tissue were estimated. The Kruskal-Wallis, Mann-Whitney U, and Bonferroni tests were used for statistical analysis. The ET approach showed good sparing effects and acceptable target coverage for the lower inner quadrantâ€”superficial (LIQ-S) and lower inner quadrantâ€”deep (LIQ-D) locations. The H-TOMO method was the least effective technique as no evaluation index achieved superiority for all tumor locations except CN. The ET method is advisable for treating LIQ-S and LIQ-D tumors, as opposed to 3D-CRT or H-TOMO, because of acceptable target coverage and much lower dose applied to surrounding tissue.
Three-dimensional charge density wave order in YBa_{2}Cu_{3}O_{6.67} at high magnetic fields
Gerber, S.; Jang, H.; Nojiri, H.; Matsuzawa, S.; Yasumura, H.; Bonn, D. A.; Liang, R.; Hardy, W. N.; Islam, Z.; Mehta, A.; Song, S.; Sikorski, M.; Stefanescu, D.; Feng, Y.; Kivelson, S. A.; Devereaux, T. P.; Shen, Z. -. X.; Kao, C. -C.; Lee, W. -S.; Zhu, D.; Lee, J. -S.
2015-11-20
In this study, charge density wave (CDW) correlations have recently been shown to universally exist in cuprate superconductors. However, their nature at high fields inferred from nuclear magnetic resonance is distinct from that measured by x-ray scattering at zero and low fields. Here we combine a pulsed magnet with an x-ray free electron laser to characterize the CDW in YBa_{2}Cu_{3}O_{6.67} via x-ray scattering in fields up to 28 Tesla. While the zero-field CDW order, which develops below T ~ 150 K, is essentially two-dimensional, at lower temperature and beyond 15 Tesla, another three-dimensionally ordered CDW emerges. The field-induced CDW onsets around the zero-field superconducting transition temperature, yet the incommensurate in-plane ordering vector is field-independent. This implies that the two forms of CDW and high-temperature superconductivity are intimately linked.
Jiang Chaowei; Feng Xueshang; Wu, S. T.; Hu Qiang E-mail: fengx@spaceweather.ac.cn E-mail: qh0001@uah.edu
2012-11-10
We apply a data-driven magnetohydrodynamics (MHD) model to investigate the three-dimensional (3D) magnetic field of NOAA active region (AR) 11117 around the time of a C-class confined flare that occurred on 2010 October 25. The MHD model, based on the spacetime conservation-element and solution-element scheme, is designed to focus on the magnetic field evolution and to consider a simplified solar atomsphere with finite plasma {beta}. Magnetic vector-field data derived from the observations at the photosphere is inputted directly to constrain the model. Assuming that the dynamic evolution of the coronal magnetic field can be approximated by successive equilibria, we solve a time sequence of MHD equilibria based on a set of vector magnetograms for AR 11117 taken by the Helioseismic and Magnetic Imager on board the Solar Dynamic Observatory around the time of the flare. The model qualitatively reproduces the basic structures of the 3D magnetic field, as supported by the visual similarity between the field lines and the coronal loops observed by the Atmospheric Imaging Assembly, which shows that the coronal field can indeed be well characterized by the MHD equilibrium in most cases. The magnetic configuration changes very little during the studied time interval of 2 hr. A topological analysis reveals that the small flare is correlated with a bald patch (BP, where the magnetic field is tangent to the photosphere), suggesting that the energy release of the flare can be understood by magnetic reconnection associated with the BP separatrices. The total magnetic flux and energy keep increasing slightly in spite of the flare, while the computed magnetic free energy drops during the flare by {approx}10{sup 30} erg, which seems to be adequate in providing the energy budget of a minor C-class confined flare.
SIMULTANEOUS DIFFERENTIAL EQUATION COMPUTER
Collier, D.M.; Meeks, L.A.; Palmer, J.P.
1960-05-10
A description is given for an electronic simulator for a system of simultaneous differential equations, including nonlinear equations. As a specific example, a homogeneous nuclear reactor system including a reactor fluid, heat exchanger, and a steam boiler may be simulated, with the nonlinearity resulting from a consideration of temperature effects taken into account. The simulator includes three operational amplifiers, a multiplier, appropriate potential sources, and interconnecting R-C networks.
Relativistic Guiding Center Equations
White, R. B.; Gobbin, M.
2014-10-01
In toroidal fusion devices it is relatively easy that electrons achieve relativistic velocities, so to simulate runaway electrons and other high energy phenomena a nonrelativistic guiding center formalism is not sufficient. Relativistic guiding center equations including flute mode time dependent field perturbations are derived. The same variables as used in a previous nonrelativistic guiding center code are adopted, so that a straightforward modifications of those equations can produce a relativistic version.
Vortices at the magnetic equator generated by hybrid Alfvén resonant waves
Hiraki, Yasutaka
2015-01-15
We performed three-dimensional magnetohydrodynamic simulations of shear Alfvén waves in a full field line system with magnetosphere-ionosphere coupling and plasma non-uniformities. Feedback instability of the Alfvén resonant modes showed various nonlinear features under the field line cavities: (i) a secondary flow shear instability occurs at the magnetic equator, (ii) trapping of the ionospheric Alfvén resonant modes facilitates deformation of field-aligned current structures, and (iii) hybrid Alfvén resonant modes grow to cause vortices and magnetic oscillations around the magnetic equator. Essential features in the initial brightening of auroral arc at substorm onsets could be explained by the dynamics of Alfvén resonant modes, which are the nature of the field line system responding to a background rapid change.
Parallel Multigrid Equation Solver
Energy Science and Technology Software Center (OSTI)
2001-09-07
Prometheus is a fully parallel multigrid equation solver for matrices that arise in unstructured grid finite element applications. It includes a geometric and an algebraic multigrid method and has solved problems of up to 76 mullion degrees of feedom, problems in linear elasticity on the ASCI blue pacific and ASCI red machines.
Flavored quantum Boltzmann equations
Cirigliano, Vincenzo; Lee, Christopher; Ramsey-Musolf, Michael J.; Tulin, Sean [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545 (United States); Center for Theoretical Physics, University of California, and Theoretical Physics Group, Lawrence Berkeley National Laboratory, Berkeley, California, 94720 (United States); Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin, 53706 (United States) and Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, California, 91125 (United States); Theory Group, TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, V6T 2A3 (Canada)
2010-05-15
We derive from first principles, using nonequilibrium field theory, the quantum Boltzmann equations that describe the dynamics of flavor oscillations, collisions, and a time-dependent mass matrix in the early universe. Working to leading nontrivial order in ratios of relevant time scales, we study in detail a toy model for weak-scale baryogenesis: two scalar species that mix through a slowly varying time-dependent and CP-violating mass matrix, and interact with a thermal bath. This model clearly illustrates how the CP asymmetry arises through coherent flavor oscillations in a nontrivial background. We solve the Boltzmann equations numerically for the density matrices, investigating the impact of collisions in various regimes.
Nazari-Golshan, A.; Nourazar, S. S.; Department of Mechanical Engineering, Amirkabir University of Technology, Tehran
2013-10-15
The time fractional modified Korteweg-de Vries (TFMKdV) equation is solved to study the nonlinear propagation of small but finite amplitude dust ion-acoustic (DIA) solitary waves in un-magnetized dusty plasma with trapped electrons. The plasma is composed of a cold ion fluid, stationary dust grains, and hot electrons obeying a trapped electron distribution. The TFMKdV equation is derived by using the semi-inverse and Agrawal's methods and then solved by the Laplace Adomian decomposition method. Our results show that the amplitude of the DIA solitary waves increases with the increase of time fractional order ?, the wave velocity v{sub 0}, and the population of the background free electrons ?. However, it is vice-versa for the deviation from isothermality parameter b, which is in agreement with the result obtained previously.
A node-centered local refinement algorithm for poisson's equation in complex geometries
McCorquodale, Peter; Colella, Phillip; Grote, David P.; Vay, Jean-Luc
2004-05-04
This paper presents a method for solving Poisson's equation with Dirichlet boundary conditions on an irregular bounded three-dimensional region. The method uses a nodal-point discretization and adaptive mesh refinement (AMR) on Cartesian grids, and the AMR multigrid solver of Almgren. The discrete Laplacian operator at internal boundaries comes from either linear or quadratic (Shortley-Weller) extrapolation, and the two methods are compared. It is shown that either way, solution error is second order in the mesh spacing. Error in the gradient of the solution is first order with linear extrapolation, but second order with Shortley-Weller. Examples are given with comparison with the exact solution. The method is also applied to a heavy-ion fusion accelerator problem, showing the advantage of adaptivity.
Menikoff, Ralph
2015-12-15
The JWL equation of state (EOS) is frequently used for the products (and sometimes reactants) of a high explosive (HE). Here we review and systematically derive important properties. The JWL EOS is of the Mie-Grueneisen form with a constant Grueneisen coefficient and a constants specific heat. It is thermodynamically consistent to specify the temperature at a reference state. However, increasing the reference state temperature restricts the EOS domain in the (V, e)-plane of phase space. The restrictions are due to the conditions that P ? 0, T ? 0, and the isothermal bulk modulus is positive. Typically, this limits the low temperature regime in expansion. The domain restrictions can result in the P-T equilibrium EOS of a partly burned HE failing to have a solution in some cases. For application to HE, the heat of detonation is discussed. Example JWL parameters for an HE, both products and reactions, are used to illustrate the restrictions on the domain of the EOS.
Generalizing the cosmic energy equation
Shtanov, Yuri; Sahni, Varun
2010-11-15
We generalize the cosmic energy equation to the case when massive particles interact via a modified gravitational potential of the form {phi}(a,r), which is allowed to explicitly depend upon the cosmological time through the expansion factor a(t). Using the nonrelativistic approximation for particle dynamics, we derive the equation for the cosmological expansion which has the form of the Friedmann equation with a renormalized gravitational constant. The generalized Layzer-Irvine cosmic energy equation and the associated cosmic virial theorem are applied to some recently proposed modifications of the Newtonian gravitational interaction between dark-matter particles. We also draw attention to the possibility that the cosmic energy equation may be used to probe the expansion history of the universe thereby throwing light on the nature of dark matter and dark energy.
Park, H.; Geiser, U.; Halder, G. J.; Schlueter, J. A.; Materials Science Division
2008-01-01
The title compound, [Zn{sub 4}(C{sub 2}H{sub 2}N{sub 3}){sub 3}(NCS){sub 3}S]{sub n}, is a three-dimensional coordination polymer consisting of tetrahedral SZn{sub 4} clusters bridged by triazole ligands. In the tetrahedral unit, three Zn atoms are connected to six bridging triazolate ligands, whereas the fourth Zn atom (site symmetry 3m) is bonded to three terminal thiocyanate anions that protrude into the void space created by the Zn-triazolate network. The network prototype is simple cubic, but a strong distortion along a body diagonal and the imposition of a polar direction by the arrangement of the molecular constituents lead to the trigonal space group R3m. This study demonstrates the use of the 3-mercapto-1,2,4-triazole ligand as an effective source for sulfide ions in the synthesis of sulfide-based coordination polymers.
Friedmann equations from entropic force
Cai Ronggen; Cao Liming; Ohta, Nobuyoshi
2010-03-15
In this paper, by use of the holographic principle together with the equipartition law of energy and the Unruh temperature, we derive the Friedmann equations of a Friedmann-Robertson-Walker universe.
Entropic corrections to Einstein equations
Hendi, S. H. [Physics Department, College of Sciences, Yasouj University, Yasouj 75914 (Iran, Islamic Republic of); Research Institute for Astronomy and Astrophysics of Maragha (RIAAM), Maragha (Iran, Islamic Republic of); Sheykhi, A. [Research Institute for Astronomy and Astrophysics of Maragha (RIAAM), Maragha (Iran, Islamic Republic of); Department of Physics, Shahid Bahonar University, P.O. Box 76175-132, Kerman (Iran, Islamic Republic of)
2011-04-15
Considering the general quantum corrections to the area law of black hole entropy and adopting the viewpoint that gravity interprets as an entropic force, we derive the modified forms of Modified Newtonian dynamics (MOND) theory of gravitation and Einstein field equations. As two special cases we study the logarithmic and power-law corrections to entropy and find the explicit form of the obtained modified equations.
Three-dimensional Modeling of Fracture Clusters in Geothermal Reservoirs
Broader source: Energy.gov [DOE]
Project objective: to develop a 3-D numerical model for simulating mode I; II; and III (tensile; shear; and tearing propagation of multiple fractures using the virtual multi-dimensional internal bond (VMIB); to predict geothermal reservoir stimulation.
Breakdown of three-dimensional Dirac semimetal state in pressurized...
Office of Scientific and Technical Information (OSTI)
Yanchun more ; Li, Xiaodong ; Liu, Jing ; Dai, Xi ; Fang, Zhong ; Cava, Robert J. ; Sun, Liling ; Zhao, Zhongxian less Publication Date: 2015-04-27 OSTI Identifier: 1178773 ...
Three dimensional simulation for Big Hill Strategic Petroleum Reserve (SPR).
Ehgartner, Brian L.; Park, Byoung Yoon; Sobolik, Steven Ronald; Lee, Moo Yul
2005-07-01
3-D finite element analyses were performed to evaluate the structural integrity of caverns located at the Strategic Petroleum Reserve's Big Hill site. State-of-art analyses simulated the current site configuration and considered additional caverns. The addition of 5 caverns to account for a full site and a full dome containing 31 caverns were modeled. Operations including both normal and cavern workover pressures and cavern enlargement due to leaching were modeled to account for as many as 5 future oil drawdowns. Under the modeled conditions, caverns were placed very close to the edge of the salt dome. The web of salt separating the caverns and the web of salt between the caverns and edge of the salt dome were reduced due to leaching. The impacts on cavern stability, underground creep closure, surface subsidence and infrastructure, and well integrity were quantified. The analyses included recently derived damage criterion obtained from testing of Big Hill salt cores. The results show that from a structural view point, many additional caverns can be safely added to Big Hill.
Three-Dimensional Composite Nanostructures for Lean NOx Emission Control
Broader source: Energy.gov [DOE]
2011 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation
Defect propagation in one-, two-, and three-dimensional compounds...
Office of Scientific and Technical Information (OSTI)
derived through the linear law dJdR. Authors: Furrer, A. ... OSTI Identifier: 1163590 GrantContract Number: ... Email address: Content: Close Send Cite: MLA Format Close ...
Radiation hardness of three-dimensional polycrystalline diamond...
Office of Scientific and Technical Information (OSTI)
of columnar electrodes perpendicular to the surface of a solidstate radiation sensor. ... ; European Laboratory for Non-Linear Spectroscopy, Via Nello Carrara 1, 50019 Sesto ...
Superconducting properties in tantalum decorated three-dimensional...
Office of Scientific and Technical Information (OSTI)
Laboratories, P.O. Box 5800, MS 1086, Albuquerque, New Mexico 87185 (United States) (Spain) (United States) Laboratorio de Bajas Temperaturas, Universidad de Salamanca, E-37008...
Three-dimensional Dendritic Needle Network model with application...
Office of Scientific and Technical Information (OSTI)
... Close Cite: Bibtex Format Close 0 pages in this document matching the terms "" Search For Terms: Enter terms in the toolbar above to search the full text of this document for ...
Novel Power Electronics Three-Dimensional Heat Exchanger: Preprint
Bennion, K.; Cousineau, J.; Lustbader, J.; Narumanchi, S.
2014-08-01
Electric drive systems for vehicle propulsion enable technologies critical to meeting challenges for energy, environmental, and economic security. Enabling cost-effective electric drive systems requires reductions in inverter power semiconductor area. As critical components of the electric drive system are made smaller, heat removal becomes an increasing challenge. In this paper, we demonstrate an integrated approach to the design of thermal management systems for power semiconductors that matches the passive thermal resistance of the packaging with the active convective cooling performance of the heat exchanger. The heat exchanger concept builds on existing semiconductor thermal management improvements described in literature and patents, which include improved bonded interface materials, direct cooling of the semiconductor packages, and double-sided cooling. The key difference in the described concept is the achievement of high heat transfer performance with less aggressive cooling techniques by optimizing the passive and active heat transfer paths. An extruded aluminum design was selected because of its lower tooling cost, higher performance, and scalability in comparison to cast aluminum. Results demonstrated a heat flux improvement of a factor of two, and a package heat density improvement over 30%, which achieved the thermal performance targets.
Three-Dimensional Composite Nanostructures for Lean NOx Emission Control
Broader source: Energy.gov [DOE]
2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting
Three-Dimensional Composite Nanostructures for Lean NOx Emission Control
Broader source: Energy.gov [DOE]
2010 DOE Vehicle Technologies and Hydrogen Programs Annual Merit Review and Peer Evaluation Meeting, June 7-11, 2010 -- Washington D.C.
Highly Ordered Tailored Three-Dimensional Hierarchical Porous...
Office of Scientific and Technical Information (OSTI)
Authors: Polsky, Ronen ; Brozik, Susan Marie ; Washburn, Cody M. ; Wheeler, David Roger ; Burckel, David Bruce ; sattayasamtsathit, sirilak ; OMahony, Aoife ; Gao, Wei ; Minteer, ...
Three dimensional seismic imaging of the Rye Patch geothermal...
Patch geothermal reservoir Authors M.A. Feighner, R. Gritto, T.M. Daley, H. Keers and E.L. Majer Published Lawrence Berkeley National Laboratory, 1999 Report Number LBNL-44119...
Three-dimensional, position-sensitive radiation detection
He, Zhong; Zhang, Feng
2010-04-06
Disclosed herein is a method of determining a characteristic of radiation detected by a radiation detector via a multiple-pixel event having a plurality of radiation interactions. The method includes determining a cathode-to-anode signal ratio for a selected interaction of the plurality of radiation interactions based on electron drift time data for the selected interaction, and determining the radiation characteristic for the multiple-pixel event based on both the cathode-to-anode signal ratio and the electron drift time data. In some embodiments, the method further includes determining a correction factor for the radiation characteristic based on an interaction depth of the plurality of radiation interactions, a lateral distance between the selected interaction and a further interaction of the plurality of radiation interactions, and the lateral positioning of the plurality of radiation interactions.
Three-Dimensional CFD FLYGT Mixer Model and Results
Lee, S. Y.
2002-04-16
The main objectives of the present work are to examine detailed flow performance of the Tank 19 FLYGT mixer improved by the previous work, to conduct sensitivity analysis for a wide range of possible boundary conditions, and to investigate transient flow behavior and loading of the FLYGT mixer. For the present study, a flow simulation method is developed to calculate the flow around a marine-type propeller configuration of the FLYGT mixer.
Detailed High-Resolution Three-Dimensional Simulations of OMEGA...
Office of Scientific and Technical Information (OSTI)
Melissa 1 ; Fowler, Malcolm M. 1 ; Gore, Robert Allen 1 ; Hayes-Sterbenz, Anna Catherine 1 ; Jungman, Gerard 1 ; Klein, Andreas 1 ; Rundberg, Robert S. 1 ; ...
Three-Dimensional Inversion of Magnetotelluric Data on a PC,...
Inversion of Magnetotelluric Data on a PC, Methodology and Applications to the Coso Geothermal Field Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference...
Three dimensional stress vector sensor array and method therefor...
Office of Scientific and Technical Information (OSTI)
A sensor array is configured based upon capacitive sensor techniques to measure stresses ... The device consists of single capacitive elements applied in a one or two dimensional ...
Three-dimensional Modeling of Fracture Clusters in Geeothermal...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
2010 Geothermal Technology Program Peer Review Report Analysis of Geothermal Reservoir Stimulation using Geomechanics-Based Stochastic Analysis of Injection-Induced Seismicity
Latin-square three-dimensional gage master
Jones, L.
1981-05-12
A gage master for coordinate measuring machines has an nxn array of objects distributed in the Z coordinate utilizing the concept of a Latin square experimental design. Using analysis of variance techniques, the invention may be used to identify sources of error in machine geometry and quantify machine accuracy.
Three-Dimensional Anatomy of a Geothermal Field Coso Southeast...
on nearly all analyses. The anomalies coincide with high levels of seismicity and with stress anomalies as determined from earthquake focal mechanism analysis and seismic...
Three-dimensional anatomy of a geothermal field, Coso, Southeast...
on nearly all analyses. The anomalies coincide with high levels of seismicity and with stress anomalies as determined from earthquake focal mechanism analysis and seismic...
Ultratough CVD single crystal diamond and three dimensional growth thereof
Hemley, Russell J.; Mao, Ho-kwang; Yan, Chih-shiue
2009-09-29
The invention relates to a single-crystal diamond grown by microwave plasma chemical vapor deposition that has a toughness of at least about 30 MPa m.sup.1/2. The invention also relates to a method of producing a single-crystal diamond with a toughness of at least about 30 MPa m.sup.1/2. The invention further relates to a process for producing a single crystal CVD diamond in three dimensions on a single crystal diamond substrate.
Three-dimensional magnetotelluric characterization of the Coso...
array profiling has been acquired over the east flank of the Coso geothermal system, CA, USA. Due to production related electromagnetic (EM) noise the permanent observatory at...
The three dimensional X-ray diffraction technique
Jensen, D. Juul; Poulsen, H.F.
2012-10-15
This introductory tutorial describes the so called 3 dimensional X-ray diffraction (3DXRD) technique, which allows bulk non-destructive structural characterizations of crystalline materials. The motivations and history behind the development of this technique are described and its potentials are sketched. Examples of the use of the technique are given and future trends and developments are suggested. The primary aim of the paper is to give 3DXRD novices an easy introduction to the technique and to describe a way from a dream to reality and new results.
Three Dimensional Simulation of the Baneberry Nuclear Event ...
Office of Scientific and Technical Information (OSTI)
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. ...
Three dimensional stress vector sensor array and method therefor...
Office of Scientific and Technical Information (OSTI)
array and method therefor You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and ...
Three-Dimensional Composite Nanostructures for Lean NOx Emission Control
Gao, Pu-Xian
2013-07-31
This final report to the Department of Energy (DOE) and National Energy Technology Laboratory (NETL) for DE-EE0000210 covers the period from October 1, 2009 to July 31, 2013. Under this project, DOE awarded UConn about $1,248,242 to conduct the research and development on a new class of 3D composite nanostructure based catalysts for lean NOx emission control. Much of the material presented here has already been submitted to DOE/NETL in quarterly technical reports. In this project, through a scalable solution process, we have successfully fabricated a new class of catalytic reactors, i.e., the composite nanostructure array (nano-array) based catalytic converters. These nanocatalysts, distinct from traditional powder washcoat based catalytic converters, directly integrate monolithic substrates together with nanostructures with well-defined size and shape during the scalable hydrothermal process. The new monolithic nanocatalysts are demonstrated to be able to save raw materials including Pt-group metals and support metal oxides by an order of magnitude, while perform well at various oxidation (e.g., CO oxidation and NO oxidation) and reduction reactions (H{sub 2} reduction of NOx) involved in the lean NOx emissions. The size, shape and arrangement of the composite nanostructures within the monolithic substrates are found to be the key in enabling the drastically reduced materials usage while maintaining the good catalytic reactivity in the enabled devices. The further understanding of the reaction kinetics associated with the unique mass transport and surface chemistry behind is needed for further optimizing the design and fabrication of good nanostructure array based catalytic converters. On the other hand, the high temperature stability, hydrothermal aging stability, as well as S-poisoning resistance have been investigated in this project on the nanocatalysts, which revealed promising results toward good chemical and mechanical robustness, as well as S-poisoning resistance. Further investigation is needed for unraveling the understanding, design and selection principles of this new class of nanostructure based monolithic catalysts.
Three-Dimensional Composite Nanostructures for Lean NOx Emission...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Emission Control Catalysts Vehicle Technologies Office Merit Review 2015: Metal Oxide Nano-Array Catalysts for Low Temperature Diesel Oxidation Ultra-efficient, Robust and ...
Three-dimensional crack growth assessment by microtopographic examination
Lloyd, W.R.; Piascik, R.S.
1995-12-31
The initial stage of the stable tearing process in two 2.3 mm sheet 2024-T3 aluminum alloy M(T) specimens are analyzed using fracture surface microtopography reconstruction techniques. The local crack tip opening angles (CTOA) in the interior of the specimens are determined relative to both crack extension and through-thickness position. The microtopographic analysis of cracks grown in the L-T and T-L orientations reveal that interior CTOA is comparable to those measured on the surface using standard optical analysis methods. Similar to surface CTOA results, interior (mid-thickness) CTOA exhibit a transient behavior; CTOA transitions from high angles, at near crack initiation, to a lower steady-state value of 5 deg. and 4.2 deg. for L-T and T-L, respectively, at crack lengths greater than 1.5mm. Fracture surface topographic projection maps are used to study the evolution of crack front tunneling during the initial stage of the fracture process. Stable tearing initiates at mid-thickness followed by a crack front tunneling process to a depth of approximately 2mm. A brief discussion of the basis of the fracture process reconstruction method is provided and comments on the general utility of microtopographic fracture surface examination for general assessment of elastic-plastic and fully-plastic fracture processes are made.
Three-dimensional tokamak equilibria in the presence of resonant...
Office of Scientific and Technical Information (OSTI)
Close Cite: Bibtex Format Close 0 pages in this document matching the terms "" Search For Terms: Enter terms in the toolbar above to search the full text of this document for ...
Three-Dimensional Crystallization of Vortex Strings in Frustrated...
Office of Scientific and Technical Information (OSTI)
GrantContract Number: AC52-06NA25396 Type: Publisher's Accepted Manuscript Journal Name: Physical Review Letters Additional Journal Information: Journal Volume: 115; Journal ...
Three-dimensional Numerical Analysis on Blade Response of Vertical...
Office of Scientific and Technical Information (OSTI)
Tidal power as a large-scale renewable source of energy has been receiving significant attention recently because of its advantages over the wind and other renewal energy sources. ...
Three-dimensional architecture for solid state radiation detectors
Parker, Sherwood
1999-01-01
A radiation-damage resistant radiation detector is formed on a substrate formed of a material doped with a first conductivity type dopant. The detector includes at least one first electrode formed of first conductivity type dopant, and at least one second electrode that is spaced-apart from the first electrode and formed of a second conductivity type dopant. Each first and second electrode penetrates into the substrate from a substrate surface, and one or more electrodes may penetrate entirely through the substrate, that is traversing from one surface to the other surface. Particulate and/or electromagnetic radiation penetrating at least a surface of the substrate releases electrons and holes in substrate regions. Because the electrodes may be formed entirely through the substrate thickness, the released charges will be a relatively small distance from at least a portion of such an electrode, e.g., a distance less than the substrate thickness. The electrons and/or holes traverse the small distance and are collected by said electrodes, thus promoting rapid detection of the radiation. By providing one or more electrodes with a dopant profile radially graded in a direction parallel to a substrate surface, an electric field results that promotes rapid collection of released electrons and said holes. Monolithic combinations of such detectors may be fabricated including CMOS electronics to process radiation signals.
Three-dimensional architecture for solid state radiation detectors
Parker, S.
1999-03-30
A radiation-damage resistant radiation detector is formed on a substrate formed of a material doped with a first conductivity type dopant. The detector includes at least one first electrode formed of first conductivity type dopant, and at least one second electrode that is spaced-apart from the first electrode and formed of a second conductivity type dopant. Each first and second electrode penetrates into the substrate from a substrate surface, and one or more electrodes may penetrate entirely through the substrate, that is traversing from one surface to the other surface. Particulate and/or electromagnetic radiation penetrating at least a surface of the substrate releases electrons and holes in substrate regions. Because the electrodes may be formed entirely through the substrate thickness, the released charges will be a relatively small distance from at least a portion of such an electrode, e.g., a distance less than the substrate thickness. The electrons and/or holes traverse the small distance and are collected by said electrodes, thus promoting rapid detection of the radiation. By providing one or more electrodes with a dopant profile radially graded in a direction parallel to a substrate surface, an electric field results that promotes rapid collection of released electrons and said holes. Monolithic combinations of such detectors may be fabricated including CMOS electronics to process radiation signals. 45 figs.
Detailed High-Resolution Three-Dimensional Simulations of OMEGA...
Office of Scientific and Technical Information (OSTI)
Resource Relation: Conference: Nuclear Explosives Design Physics Conference ; 2015-10-19 - 2015-10-23 ; Los Alamos, New Mexico, United States Research Org: Los Alamos National ...
Device fabrication: Three-dimensional printed electronics (Journal...
Office of Scientific and Technical Information (OSTI)
of Publication: United States Language: English Subject: solar (photovoltaic), solid state lighting, phonons, thermal conductivity, electrodes - solar, materials and chemistry...
Three dimensional stress vector sensor array and method therefor
Pfeifer, Kent Bryant; Rudnick, Thomas Jeffery
2005-07-05
A sensor array is configured based upon capacitive sensor techniques to measure stresses at various positions in a sheet simultaneously and allow a stress map to be obtained in near real-time. The device consists of single capacitive elements applied in a one or two dimensional array to measure the distribution of stresses across a mat surface in real-time as a function of position for manufacturing and test applications. In-plane and normal stresses in rolling bodies such as tires may thus be monitored.
Three-Dimensional Seismic Imaging Of The Rye Patch Geothermal...
first arrival travel times, normal moveout correction, 3-D stack, deconvolution, time migration, and depth conversion. The final data set represents a 3-D cube of the subsurface...
Three-dimensional tokamak equilibria in the presence of resonant...
Office of Scientific and Technical Information (OSTI)
magnitude existing in present day devices, and contemplated for future devices, can produce a set of magnetic islands occupying a significant fraction of the plasma cross-section. ...
Methods and devices for fabricating three-dimensional nanoscale structures
Rogers, John A.; Jeon, Seokwoo; Park, Jangung
2010-04-27
The present invention provides methods and devices for fabricating 3D structures and patterns of 3D structures on substrate surfaces, including symmetrical and asymmetrical patterns of 3D structures. Methods of the present invention provide a means of fabricating 3D structures having accurately selected physical dimensions, including lateral and vertical dimensions ranging from 10s of nanometers to 1000s of nanometers. In one aspect, methods are provided using a mask element comprising a conformable, elastomeric phase mask capable of establishing conformal contact with a radiation sensitive material undergoing photoprocessing. In another aspect, the temporal and/or spatial coherence of electromagnetic radiation using for photoprocessing is selected to fabricate complex structures having nanoscale features that do not extend entirely through the thickness of the structure fabricated.
Quest for the quantum limit in three dimensional metals
Brooks, J.S.; Qualls, J.S.; Engel, L.W. [Florida State Univ., Tallahassee, FL (United States)] [and others
1996-11-01
The purpose of this work is to exploit ultra-high, flux compression type magnetic fields to achieve magnetic energies which are on the same or greater scale of the electronic structure in metallic systems. Under such conditions a metal. may become an insulator, may acquire a completely new electronic structure, or may develop novel configurations of electronic order. In this paper we consider experiments on quasi-two dimensional molecular conductors in both non-destructive pulsed fields to 60 T and in destructive flux compression fields to 700 T at low temperatures. New results on the molecular conductors {alpha}-(BEDT-TTF) {sub 2}NH{sub 4}Hg(SCN){sub 4} and (TMTSF){sub 2}ClO{sub 4} are discussed in experiments up to 60 T at low temperatures, and preliminary results on {alpha}-(BEDT-TTF){sub 2}NH{sub 4}Hg(SON){sub 4} in the 700 T MC1 series flux compression generators are presented. We argue that true direct dc electrical transport measurements in these materials at low temperatures up to 700 T appear to be within reach.
Ordinary Differential Equation System Solver
Energy Science and Technology Software Center (OSTI)
1992-03-05
LSODE is a package of subroutines for the numerical solution of the initial value problem for systems of first order ordinary differential equations. The package is suitable for either stiff or nonstiff systems. For stiff systems the Jacobian matrix may be treated in either full or banded form. LSODE can also be used when the Jacobian can be approximated by a band matrix.
Li, Zhihui; Ma, Qiang; Wu, Junlin; Jiang, Xinyu; Zhang, Hanxin
2014-12-09
Based on the Gas-Kinetic Unified Algorithm (GKUA) directly solving the Boltzmann model equation, the effect of rotational non-equilibrium is investigated recurring to the kinetic Rykov model with relaxation property of rotational degrees of freedom. The spin movement of diatomic molecule is described by moment of inertia, and the conservation of total angle momentum is taken as a new Boltzmann collision invariant. The molecular velocity distribution function is integrated by the weight factor on the internal energy, and the closed system of two kinetic controlling equations is obtained with inelastic and elastic collisions. The optimization selection technique of discrete velocity ordinate points and numerical quadrature rules for macroscopic flow variables with dynamic updating evolvement are developed to simulate hypersonic flows, and the gas-kinetic numerical scheme is constructed to capture the time evolution of the discretized velocity distribution functions. The gas-kinetic boundary conditions in thermodynamic non-equilibrium and numerical procedures are studied and implemented by directly acting on the velocity distribution function, and then the unified algorithm of Boltzmann model equation involving non-equilibrium effect is presented for the whole range of flow regimes. The hypersonic flows involving non-equilibrium effect are numerically simulated including the inner flows of shock wave structures in nitrogen with different Mach numbers of 1.5-Ma-25, the planar ramp flow with the whole range of Knudsen numbers of 0.0009-Kn-10 and the three-dimensional re-entering flows around tine double-cone body.
Equation of State Project Overview
Crockett, Scott
2015-09-11
A general overview of the Equation of State (EOS) Project will be presented. The goal is to provide the audience with an introduction of what our more advanced methods entail (DFT, QMD, etc.. ) and how these models are being utilized to better constrain the thermodynamic models. These models substantially reduce our regions of interpolation between the various thermodynamic limits. I will also present a variety example of recent EOS work.
Equation of state and contact of a strongly interacting Bose gas in the normal state
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Liu, Xia -Ji; Mulkerin, Brendan; He, Lianyi; Hu, Hui
2015-04-27
Here, we theoretically investigate the equation of state and Tan's contact of a nondegenerate three-dimensional Bose gas near a broad Feshbach resonance, within the framework of large-N expansion. Our results agree with the path-integral Monte Carlo simulations in the weak-coupling limit and recover the second-order virial expansion predictions at strong interactions and high temperatures. At resonance, we find that the chemical potential and energy are significantly enhanced by the strong repulsion, while the entropy does not change significantly. With increasing temperature, the two-body contact initially increases and then decreases like Tâ€“1 at large temperature, and therefore exhibits a peak structuremoreÂ Â» at about 4Tc0, where Tc0 is the Bose-Einstein condensation temperature of an ideal, noninteracting Bose gas. These results may be experimentally examined with a nondegenerate unitary Bose gas, where the three-body recombination rate is substantially reduced. In particular, the nonmonotonic temperature dependence of the two-body contact could be inferred from the momentum distribution measurement.Â«Â less
Nguyen, Dang Van; Li, Jing-Rebecca; Grebenkov, Denis; Le Bihan, Denis
2014-04-15
The complex transverse water proton magnetization subject to diffusion-encoding magnetic field gradient pulses in a heterogeneous medium can be modeled by the multiple compartment Blochâ€“Torrey partial differential equation (PDE). In addition, steady-state Laplace PDEs can be formulated to produce the homogenized diffusion tensor that describes the diffusion characteristics of the medium in the long time limit. In spatial domains that model biological tissues at the cellular level, these two types of PDEs have to be completed with permeability conditions on the cellular interfaces. To solve these PDEs, we implemented a finite elements method that allows jumps in the solution at the cell interfaces by using double nodes. Using a transformation of the Blochâ€“Torrey PDE we reduced oscillations in the searched-for solution and simplified the implementation of the boundary conditions. The spatial discretization was then coupled to the adaptive explicit Rungeâ€“Kuttaâ€“Chebyshev time-stepping method. Our proposed method is second order accurate in space and second order accurate in time. We implemented this method on the FEniCS C++ platform and show time and spatial convergence results. Finally, this method is applied to study some relevant questions in diffusion MRI.
Germanium multiphase equation of state
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Crockett, Scott D.; Lorenzi-Venneri, Giulia De; Kress, Joel D.; Rudin, Sven P.
2014-05-07
A new SESAME multiphase germanium equation of state (EOS) has been developed using the best available experimental data and density functional theory (DFT) calculations. The equilibrium EOS includes the Ge I (diamond), the Ge II (Î˛-Sn) and the liquid phases. The foundation of the EOS is based on density functional theory calculations which are used to determine the cold curve and the Debye temperature. Results are compared to Hugoniot data through the solid-solid and solid-liquid transitions. We propose some experiments to better understand the dynamics of this element
Universal equation for Efimov states
Braaten, Eric; Hammer, H.-W.; Kusunoki, M.
2003-02-01
Efimov states are a sequence of shallow three-body bound states that arise when the two-body scattering length is large. Efimov showed that the binding energies of these states can be calculated in terms of the scattering length and a three-body parameter by solving a transcendental equation involving a universal function of one variable. We calculate this universal function using effective field theory and use it to describe the three-body system of {sup 4}He atoms. We also extend Efimov's theory to include the effects of deep two-body bound states, which give widths to the Efimov states.
The equation of state of nuclear matter
Gandolfi, Stefano; Carlson, Joseph Allen
2015-06-30
A brief status report of research on equation of state (EOS) of nuclear matter is provided, along with two graphs.
Product equation of state for polysulfone
Ticknor, Christopher
2015-09-30
Here we review the new polysulfone product equation of state (EOS) made with magpie, a chemical equilibrium code.
Hadizadeh, M. R.; Tomio, Lauro; Bayegan, S.
2011-05-15
A recently developed three-dimensional approach (without partial-wave decomposition) is considered to investigate solutions of Faddeev-Yakubovsky integral equations in momentum space for three- and four-body bound states, with the inclusion of three-body forces. In the calculations of the binding energies, spin-dependent nucleon-nucleon (NN) potential models [soft-core potential S3, Malfliet-Tjon (MT) I-III, Yamaguchi-type potentials (YS), and P{sub 5.5}-model of Gibson-Lehman (P{sub 55}GL)] are considered along with the scalar two-meson exchange three-body potential. The presently reported results agree well with the ones obtained by other techniques, demonstrating the advantage of an approach in which the formalism is much more simplified and easy to manage for direct computation.
Equation determines pressure drop in coiled tubing
Yang, Y.S.
1995-12-04
A single equation can determine the pressure drop in wells with laminar, transitional, and turbulent incompressible fluid flow in coiled tubing or other steel tubulars. The single equation is useful, especially in computer-aided design and operations. The equation is derived and illustrated by an example.
Boundary conditions for the subdiffusion equation
Shkilev, V. P.
2013-04-15
The boundary conditions for the subdiffusion equations are formulated using the continuous-time random walk model, as well as several versions of the random walk model on an irregular lattice. It is shown that the boundary conditions for the same equation in different models have different forms, and this difference considerably affects the solutions of this equation.
Double distributions and evolution equations
A.V. Radyushkin
1998-05-01
Applications of perturbative QCD to deeply virtual Compton scattering and hard exclusive meson electroproduction processes require a generalization of usual parton distributions for the case when long-distance information is accumulated in nonforward matrix elements < p{prime} {vert_bar}O(0,z){vert_bar}p > of quark and gluon light-cone operators. In their previous papers the authors used two types of nonperturbative functions parameterizing such matrix elements: double distributions F(x,y;t) and nonforward distribution functions F{sub {zeta}}(X;t). Here they discuss in more detail the double distributions (DD's) and evolution equations which they satisfy. They propose simple models for F(x,y;t=0) DD's with correct spectral and symmetry properties which also satisfy the reduction relations connecting them to the usual parton densities f(x). In this way, they obtain self-consistent models for the {zeta}-dependence of nonforward distributions. They show that, for small {zeta}, one can easily obtain nonforward distributions (in the X > {zeta} region) from the parton densities: F{sub {zeta}} (X;t=0) {approx} f(X{minus}{zeta}/2).
Scalable Equation of State Capability
Epperly, T W; Fritsch, F N; Norquist, P D; Sanford, L A
2007-12-03
The purpose of this techbase project was to investigate the use of parallel array data types to reduce the memory footprint of the Livermore Equation Of State (LEOS) library. Addressing the memory scalability of LEOS is necessary to run large scientific simulations on IBM BG/L and future architectures with low memory per processing core. We considered using normal MPI, one-sided MPI, and Global Arrays to manage the distributed array and ended up choosing Global Arrays because it was the only communication library that provided the level of asynchronous access required. To reduce the runtime overhead using a parallel array data structure, a least recently used (LRU) caching algorithm was used to provide a local cache of commonly used parts of the parallel array. The approach was initially implemented in a isolated copy of LEOS and was later integrated into the main trunk of the LEOS Subversion repository. The approach was tested using a simple test. Testing indicated that the approach was feasible, and the simple LRU caching had a 86% hit rate.
Darboux transformation for the NLS equation
Aktosun, Tuncay; Mee, Cornelis van der
2010-03-08
We analyze a certain class of integral equations associated with Marchenko equations and Gel'fand-Levitan equations. Such integral equations arise through a Fourier transformation on various ordinary differential equations involving a spectral parameter. When the integral operator is perturbed by a finite-rank perturbation, we explicitly evaluate the change in the solution in terms of the unperturbed quantities and the finite-rank perturbation. We show that this result provides a fundamental approach to derive Darboux transformations for various systems of ordinary differential operators. We illustrate our theory by providing the explicit Darboux transformation for the Zakharov-Shabat system and show how the potential and wave function change when a simple discrete eigenvalue is added to the spectrum, and thus we also provide a one-parameter family of Darboux transformations for the nonlinear Schroedinger equation.
The Boltzmann equation in the difference formulation
Szoke, Abraham; Brooks III, Eugene D.
2015-05-06
First we recall the assumptions that are needed for the validity of the Boltzmann equation and for the validity of the compressible Euler equations. We then present the difference formulation of these equations and make a connection with the time-honored Chapman - Enskog expansion. We discuss the hydrodynamic limit and calculate the thermal conductivity of a monatomic gas, using a simplified approximation for the collision term. Our formulation is more consistent and simpler than the traditional derivation.
Microsoft PowerPoint - neely2004session3
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
* Map physical space to logical rectangular coordinates * Solve inverse Laplace equation Equipotential Relaxation Equipotential Relaxation x y Logical space Physical...
The generalized Schrödinger–Langevin equation
Bargueńo, Pedro; Miret-Artés, Salvador
2014-07-15
In this work, for a Brownian particle interacting with a heat bath, we derive a generalization of the so-called Schrödinger–Langevin or Kostin equation. This generalization is based on a nonlinear interaction model providing a state-dependent dissipation process exhibiting multiplicative noise. Two straightforward applications to the measurement process are then analyzed, continuous and weak measurements in terms of the quantum Bohmian trajectory formalism. Finally, it is also shown that the generalized uncertainty principle, which appears in some approaches to quantum gravity, can be expressed in terms of this generalized equation. -- Highlights: •We generalize the Kostin equation for arbitrary system–bath coupling. •This generalization is developed both in the Schrödinger and Bohmian formalisms. •We write the generalized Kostin equation for two measurement problems. •We reformulate the generalized uncertainty principle in terms of this equation.
Fokker-Planck equation in mirror research
Post, R.F.
1983-08-11
Open confinement systems based on the magnetic mirror principle depend on the maintenance of particle distributions that may deviate substantially from Maxwellian distributions. Mirror research has therefore from the beginning relied on theoretical predictions of non-equilibrium rate processes obtained from solutions to the Fokker-Planck equation. The F-P equation plays three roles: Design of experiments, creation of classical standards against which to compare experiment, and predictions concerning mirror based fusion power systems. Analytical and computational approaches to solving the F-P equation for mirror systems will be reviewed, together with results and examples that apply to specific mirror systems, such as the tandem mirror.
Explicit Expressions for 3D Boundary Integrals in Potential Theory
Nintcheu Fata, Sylvain
2009-01-01
On employing isoparametric, piecewise linear shape functions over a flat triangular domain, exact expressions are derived for all surface potentials involved in the numerical solution of three-dimensional singular and hyper-singular boundary integral equations of potential theory. These formulae, which are valid for an arbitrary source point in space, are represented as analytic expressions over the edges of the integration triangle. They can be used to solve integral equations defined on polygonal boundaries via the collocation method or may be utilized as analytic expressions for the inner integrals in the Galerkin technique. Also, the constant element approximation can be directly obtained with no extra effort. Sample problems solved by the collocation boundary element method for the Laplace equation are included to validate the proposed formulae.
Equator Appliance: ENERGY STAR Referral (EZ 3720)
Broader source: Energy.gov [DOE]
DOE referred Equator Appliance clothes washer EZ 3720 to EPA, brand manager of the ENERGY STAR program, for appropriate action after DOE testing revealed that the model does not meet ENERGY STAR requirements.
Coherency Does Not Equate to Stability
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
for Coherency Does Not Equate to Stability LLNL BES Programs Highlight Coherency Does Not Equate to Stability As-grown nanotwin (NT) copper (A) SEM image. (B) An edge-on inverse pole figure orientation mapping (IPFOM) image, the coherent and incoherent twin boundaries are labeled as CTB and ITB (inside circles), respectively. (C) A high-resolution IPFOM image of CTBs. Some ITB segments are marked with white arrows. (D) An IPFOM image of along columnar grain boundary showing numerous ITB segments
Pierantozzi, T.; Vazquez, L.
2005-11-01
Through fractional calculus and following the method used by Dirac to obtain his well-known equation from the Klein-Gordon equation, we analyze a possible interpolation between the Dirac and the diffusion equations in one space dimension. We study the transition between the hyperbolic and parabolic behaviors by means of the generalization of the D'Alembert formula for the classical wave equation and the invariance under space and time inversions of the interpolating fractional evolution equations Dirac like. Such invariance depends on the values of the fractional index and is related to the nonlocal property of the time fractional differential operator. For this system of fractional evolution equations, we also find an associated conserved quantity analogous to the Hamiltonian for the classical Dirac case.
Equation of State from Lattice QCD Calculations (Conference)...
Office of Scientific and Technical Information (OSTI)
Conference: Equation of State from Lattice QCD Calculations Citation Details In-Document Search Title: Equation of State from Lattice QCD Calculations You are accessing a...
An Acoustic Wave Equation for Tilted Transversely Isotropic Media...
Office of Scientific and Technical Information (OSTI)
An Acoustic Wave Equation for Tilted Transversely Isotropic Media Citation Details In-Document Search Title: An Acoustic Wave Equation for Tilted Transversely Isotropic Media ...
Solving the power flow equations: a monotone operator approach...
Office of Scientific and Technical Information (OSTI)
Technical Report: Solving the power flow equations: a monotone operator approach Citation Details In-Document Search Title: Solving the power flow equations: a monotone operator ...
Equation of State Measurements by Radiography Provide Evidence...
Office of Scientific and Technical Information (OSTI)
Equation of State Measurements by Radiography Provide Evidence for a Liquid-Liquid Phase Transition in Cerium Citation Details In-Document Search Title: Equation of State ...
Nonparametric reconstruction of the dark energy equation of state...
Office of Scientific and Technical Information (OSTI)
energy equation of state from diverse data sets Citation Details In-Document Search Title: Nonparametric reconstruction of the dark energy equation of state from diverse data ...
Solves the Multigroup Neutron Diffusion Equation
Energy Science and Technology Software Center (OSTI)
1995-06-23
GNOMER is a program which solves the multigroup neutron diffusion equation in 1D, 2D and 3D cartesian geometry. The program is designed to calculate the global core power distributions (with thermohydraulic feedbacks), as well as power distribution and homogenized cross sections over a fuel assembly.
Kansa, E.; Shumlak, U.; Tsynkov, S.
2013-02-01
Confining dense plasma in a field reversed configuration (FRC) is considered a promising approach to fusion. Numerical simulation of this process requires setting artificial boundary conditions (ABCs) for the magnetic field because whereas the plasma itself occupies a bounded region (within the FRC coils), the field extends from this region all the way to infinity. If the plasma is modeled using single fluid magnetohydrodynamics (MHD), then the exterior magnetic field can be considered quasi-static. This field has a scalar potential governed by the Laplace equation. The quasi-static ABC for the magnetic field is obtained using the method of difference potentials, in the form of a discrete Calderon boundary equation with projection on the artificial boundary shaped as a parallelepiped. The Calderon projection itself is computed by convolution with the discrete fundamental solution on the three-dimensional Cartesian grid.
Changing the Equation in STEM Education
Broader source: Energy.gov [DOE]
Editor's Note: This is a cross post of an announcement that the White House featured on its blog last week.Â Check out the video below for Secretary Chu's thoughts on how an education in math and science helps students understand the world and deal with the pressing issues of our time. Today, President Obama announced the launch of Change the Equation, a CEO-led effort to dramatically improve education in science, technology, engineering, and math (STEM), as part of his â€śEducate to Innovateâ€ť campaign. Change the Equation is a non-profit organization dedicated to mobilizing the business community to improve the quality of STEM education in the United States.
The quasicontinuum Fokker-Plank equation
Alexander, Francis J
2008-01-01
We present a regularized Fokker-Planck equation with more accurate short-time and high-frequency behavior for continuous-time, discrete-state systems. The regularization preserves crucial aspects of state-space discreteness lost in the standard Kramers-Moyal expansion. We apply the method to a simple example of biochemical reaction kinetics and to a two-dimensional symmetric random walk, and suggest its application to more complex systerns.