Science.gov

Sample records for 3d electromagnetic code

  1. EMPulse, a new 3-D simulation code for electromagnetic pulse studies

    NASA Astrophysics Data System (ADS)

    Cohen, Bruce; Eng, Chester; Farmer, William; Friedman, Alex; Grote, David; Kruger, Hans; Larson, David

    2016-10-01

    EMPulse is a comprehensive and modern 3-D simulation code for electro-magnetic pulse (EMP) formation and propagation studies, being developed at LLNL as part of a suite of codes to study E1 EMP originating from prompt gamma rays. EMPulse builds upon the open-source Warp particle-in-cell code framework developed by members of this team and collaborators at other institutions. The goal of this endeavor is a new tool enabling the detailed and self-consistent study of multi-dimensional effects in geometries that have typically been treated only approximately. Here we present an overview of the project, the models and methods that have been developed and incorporated into EMPulse, tests of these models, comparisons to simulations undertaken in CHAP-lite (derived from the legacy code CHAP due to C. Longmire and co-workers), and some approaches to increased computational efficiency being studied within our project. This work was performed under the auspices of the U.S. DOE by Lawrence Livermore National Security, LLC, Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  2. Parallel CARLOS-3D code development

    SciTech Connect

    Putnam, J.M.; Kotulski, J.D.

    1996-02-01

    CARLOS-3D is a three-dimensional scattering code which was developed under the sponsorship of the Electromagnetic Code Consortium, and is currently used by over 80 aerospace companies and government agencies. The code has been extensively validated and runs on both serial workstations and parallel super computers such as the Intel Paragon. CARLOS-3D is a three-dimensional surface integral equation scattering code based on a Galerkin method of moments formulation employing Rao- Wilton-Glisson roof-top basis for triangular faceted surfaces. Fully arbitrary 3D geometries composed of multiple conducting and homogeneous bulk dielectric materials can be modeled. This presentation describes some of the extensions to the CARLOS-3D code, and how the operator structure of the code facilitated these improvements. Body of revolution (BOR) and two-dimensional geometries were incorporated by simply including new input routines, and the appropriate Galerkin matrix operator routines. Some additional modifications were required in the combined field integral equation matrix generation routine due to the symmetric nature of the BOR and 2D operators. Quadrilateral patched surfaces with linear roof-top basis functions were also implemented in the same manner. Quadrilateral facets and triangular facets can be used in combination to more efficiently model geometries with both large smooth surfaces and surfaces with fine detail such as gaps and cracks. Since the parallel implementation in CARLOS-3D is at high level, these changes were independent of the computer platform being used. This approach minimizes code maintenance, while providing capabilities with little additional effort. Results are presented showing the performance and accuracy of the code for some large scattering problems. Comparisons between triangular faceted and quadrilateral faceted geometry representations will be shown for some complex scatterers.

  3. (abstract) 3D Electromagnetic Plasma Particle Simulations

    NASA Technical Reports Server (NTRS)

    Wang, J.; Liewer, P. C.; Lyster, P.; Decyk, V. K.

    1993-01-01

    A 3D electromagnetic plasma particle-in-cell code has been developed using the General Concurrent PIC algorithm. The GCPIC algorithm uses a domain decomposition to divide the computation among the processors. Particles must be exchanged between processors as they move. The efficiencies for 1-, 2-, and 3-dimensional partitions of the three dimensional domain are compared, and the algorithm is found to be very efficient even when a large fraction (e.g., 30%) of the particles must be exchanged at every time step. This PIC code has been used to perform simulations of a variety of space plasma physics problems. Results of three applications will be discussed: 1) plasma disturbances induced by moving conducting bodies in a magnetized plasma; 2) plasma plume interactions; and 3) solar wind termination shock.

  4. TACO3D. 3-D Finite Element Heat Transfer Code

    SciTech Connect

    Mason, W.E.

    1992-03-04

    TACO3D is a three-dimensional, finite-element program for heat transfer analysis. An extension of the two-dimensional TACO program, it can perform linear and nonlinear analyses and can be used to solve either transient or steady-state problems. The program accepts time-dependent or temperature-dependent material properties, and materials may be isotropic or orthotropic. A variety of time-dependent and temperature-dependent boundary conditions and loadings are available including temperature, flux, convection, and radiation boundary conditions and internal heat generation. Additional specialized features treat enclosure radiation, bulk nodes, and master/slave internal surface conditions (e.g., contact resistance). Data input via a free-field format is provided. A user subprogram feature allows for any type of functional representation of any independent variable. A profile (bandwidth) minimization option is available. The code is limited to implicit time integration for transient solutions. TACO3D has no general mesh generation capability. Rows of evenly-spaced nodes and rows of sequential elements may be generated, but the program relies on separate mesh generators for complex zoning. TACO3D does not have the ability to calculate view factors internally. Graphical representation of data in the form of time history and spatial plots is provided through links to the POSTACO and GRAPE postprocessor codes.

  5. 3-D Electromagnetic Instabilities in Current Sheet

    NASA Astrophysics Data System (ADS)

    Wang, Zhenyu; Lin, Yu; Wang, Xueyi; Chen, Liu; Tummel, Kurt

    2016-10-01

    3-D electromagnetic instabilities in a Harris current sheet with a finite guide magnetic field BG are systematically studied by employing the gyrokinetic electron and fully kinetic ion (GeFi) particle model with a realistic mass ratio mi /me . Our studies show that lower-hybrid drift instability (LHDI) with k√{ρiρe } 1 and drift kink instability (DKI) and drift sausage instability (DSI) with kρi 1 are excited in the current sheet. The most unstable DKI is away from k . B = 0 , and the most unstable DSI is at k . B = 0 , where k ≡ (kx ,ky) , with kx being along the anti-parallel field direction and ky is along the current direction. On the other hand, an instability with a compressional magnetic field perturbation located at the center of current sheet is also excited under a relatively large BG, and its maximum growth rate is at k × B = 0 . The presence and structure of these instabilities as a function of BG is presented. The GeFi simulation results are compared with those from the fully kinetic particle simulation.

  6. Beam Optics Analysis - An Advanced 3D Trajectory Code

    SciTech Connect

    Ives, R. Lawrence; Bui, Thuc; Vogler, William; Neilson, Jeff; Read, Mike; Shephard, Mark; Bauer, Andrew; Datta, Dibyendu; Beal, Mark

    2006-01-03

    Calabazas Creek Research, Inc. has completed initial development of an advanced, 3D program for modeling electron trajectories in electromagnetic fields. The code is being used to design complex guns and collectors. Beam Optics Analysis (BOA) is a fully relativistic, charged particle code using adaptive, finite element meshing. Geometrical input is imported from CAD programs generating ACIS-formatted files. Parametric data is inputted using an intuitive, graphical user interface (GUI), which also provides control of convergence, accuracy, and post processing. The program includes a magnetic field solver, and magnetic information can be imported from Maxwell 2D/3D and other programs. The program supports thermionic emission and injected beams. Secondary electron emission is also supported, including multiple generations. Work on field emission is in progress as well as implementation of computer optimization of both the geometry and operating parameters. The principle features of the program and its capabilities are presented.

  7. 3D Electromagnetic inversion using conjugate gradients

    SciTech Connect

    Newman, G.A.; Alumbaugh, D.L.

    1997-06-01

    In large scale 3D EM inverse problems it may not be possible to directly invert a full least-squares system matrix involving model sensitivity elements. Thus iterative methods must be employed. For the inverse problem, we favor either a linear or non-linear (NL) CG scheme, depending on the application. In a NL CG scheme, the gradient of the objective function is required at each relaxation step along with a univariate line search needed to determine the optimum model update. Solution examples based on both approaches will be presented.

  8. Electromagnetic particle simulation codes

    NASA Technical Reports Server (NTRS)

    Pritchett, P. L.

    1985-01-01

    Electromagnetic particle simulations solve the full set of Maxwell's equations. They thus include the effects of self-consistent electric and magnetic fields, magnetic induction, and electromagnetic radiation. The algorithms for an electromagnetic code which works directly with the electric and magnetic fields are described. The fields and current are separated into transverse and longitudinal components. The transverse E and B fields are integrated in time using a leapfrog scheme applied to the Fourier components. The particle pushing is performed via the relativistic Lorentz force equation for the particle momentum. As an example, simulation results are presented for the electron cyclotron maser instability which illustrate the importance of relativistic effects on the wave-particle resonance condition and on wave dispersion.

  9. RHOCUBE: 3D density distributions modeling code

    NASA Astrophysics Data System (ADS)

    Nikutta, Robert; Agliozzo, Claudia

    2016-11-01

    RHOCUBE models 3D density distributions on a discrete Cartesian grid and their integrated 2D maps. It can be used for a range of applications, including modeling the electron number density in LBV shells and computing the emission measure. The RHOCUBE Python package provides several 3D density distributions, including a powerlaw shell, truncated Gaussian shell, constant-density torus, dual cones, and spiralling helical tubes, and can accept additional distributions. RHOCUBE provides convenient methods for shifts and rotations in 3D, and if necessary, an arbitrary number of density distributions can be combined into the same model cube and the integration ∫ dz performed through the joint density field.

  10. PB3D: A new code for edge 3-D ideal linear peeling-ballooning stability

    NASA Astrophysics Data System (ADS)

    Weyens, T.; Sánchez, R.; Huijsmans, G.; Loarte, A.; García, L.

    2017-02-01

    A new numerical code PB3D (Peeling-Ballooning in 3-D) is presented. It implements and solves the intermediate-to-high-n ideal linear magnetohydrodynamic stability theory extended to full edge 3-D magnetic toroidal configurations in previous work [1]. The features that make PB3D unique are the assumptions on the perturbation structure through intermediate-to-high mode numbers n in general 3-D configurations, while allowing for displacement of the plasma edge. This makes PB3D capable of very efficient calculations of the full 3-D stability for the output of multiple equilibrium codes. As first verification, it is checked that results from the stability code MISHKA [2], which considers axisymmetric equilibrium configurations, are accurately reproduced, and these are then successfully extended to 3-D configurations, through comparison with COBRA [3], as well as using checks on physical consistency. The non-intuitive 3-D results presented serve as a tentative first proof of the capabilities of the code.

  11. MOM3D/EM-ANIMATE - MOM3D WITH ANIMATION CODE

    NASA Technical Reports Server (NTRS)

    Shaeffer, J. F.

    1994-01-01

    MOM3D (LAR-15074) is a FORTRAN method-of-moments electromagnetic analysis algorithm for open or closed 3-D perfectly conducting or resistive surfaces. Radar cross section with plane wave illumination is the prime analysis emphasis; however, provision is also included for local port excitation for computing antenna gain patterns and input impedances. The Electric Field Integral Equation form of Maxwell's equations is solved using local triangle couple basis and testing functions with a resultant system impedance matrix. The analysis emphasis is not only for routine RCS pattern predictions, but also for phenomenological diagnostics: bistatic imaging, currents, and near scattered/total electric fields. The images, currents, and near fields are output in form suitable for animation. MOM3D computes the full backscatter and bistatic radar cross section polarization scattering matrix (amplitude and phase), body currents and near scattered and total fields for plane wave illumination. MOM3D also incorporates a new bistatic k space imaging algorithm for computing down range and down/cross range diagnostic images using only one matrix inversion. MOM3D has been made memory and cpu time efficient by using symmetric matrices, symmetric geometry, and partitioned fixed and variable geometries suitable for design iteration studies. MOM3D may be run interactively or in batch mode on 486 IBM PCs and compatibles, UNIX workstations or larger computers. A 486 PC with 16 megabytes of memory has the potential to solve a 30 square wavelength (containing 3000 unknowns) symmetric configuration. Geometries are described using a triangular mesh input in the form of a list of spatial vertex points and a triangle join connection list. The EM-ANIMATE (LAR-15075) program is a specialized visualization program that displays and animates the near-field and surface-current solutions obtained from an electromagnetics program, in particular, that from MOM3D. The EM-ANIMATE program is windows based and

  12. Multitasking the code ARC3D. [for computational fluid dynamics

    NASA Technical Reports Server (NTRS)

    Barton, John T.; Hsiung, Christopher C.

    1986-01-01

    The CRAY multitasking system was developed in order to utilize all four processors and sharply reduce the wall clock run time. This paper describes the techniques used to modify the computational fluid dynamics code ARC3D for this run and analyzes the achieved speedup. The ARC3D code solves either the Euler or thin-layer N-S equations using an implicit approximate factorization scheme. Results indicate that multitask processing can be used to achieve wall clock speedup factors of over three times, depending on the nature of the program code being used. Multitasking appears to be particularly advantageous for large-memory problems running on multiple CPU computers.

  13. Interface requirements to couple thermal-hydraulic codes to 3D neutronic codes

    SciTech Connect

    Langenbuch, S.; Austregesilo, H.; Velkov, K.

    1997-07-01

    The present situation of thermalhydraulics codes and 3D neutronics codes is briefly described and general considerations for coupling of these codes are discussed. Two different basic approaches of coupling are identified and their relative advantages and disadvantages are discussed. The implementation of the coupling for 3D neutronics codes in the system ATHLET is presented. Meanwhile, this interface is used for coupling three different 3D neutronics codes.

  14. Image Appraisal for 2D and 3D Electromagnetic Inversion

    SciTech Connect

    Alumbaugh, D.L.; Newman, G.A.

    1999-01-28

    Linearized methods are presented for appraising image resolution and parameter accuracy in images generated with two and three dimensional non-linear electromagnetic inversion schemes. When direct matrix inversion is employed, the model resolution and posterior model covariance matrices can be directly calculated. A method to examine how the horizontal and vertical resolution varies spatially within the electromagnetic property image is developed by examining the columns of the model resolution matrix. Plotting the square root of the diagonal of the model covariance matrix yields an estimate of how errors in the inversion process such as data noise and incorrect a priori assumptions about the imaged model map into parameter error. This type of image is shown to be useful in analyzing spatial variations in the image sensitivity to the data. A method is analyzed for statistically estimating the model covariance matrix when the conjugate gradient method is employed rather than a direct inversion technique (for example in 3D inversion). A method for calculating individual columns of the model resolution matrix using the conjugate gradient method is also developed. Examples of the image analysis techniques are provided on 2D and 3D synthetic cross well EM data sets, as well as a field data set collected at the Lost Hills Oil Field in Central California.

  15. MOM3D method of moments code theory manual

    NASA Technical Reports Server (NTRS)

    Shaeffer, John F.

    1992-01-01

    MOM3D is a FORTRAN algorithm that solves Maxwell's equations as expressed via the electric field integral equation for the electromagnetic response of open or closed three dimensional surfaces modeled with triangle patches. Two joined triangles (couples) form the vector current unknowns for the surface. Boundary conditions are for perfectly conducting or resistive surfaces. The impedance matrix represents the fundamental electromagnetic interaction of the body with itself. A variety of electromagnetic analysis options are possible once the impedance matrix is computed including backscatter radar cross section (RCS), bistatic RCS, antenna pattern prediction for user specified body voltage excitation ports, RCS image projection showing RCS scattering center locations, surface currents excited on the body as induced by specified plane wave excitation, and near field computation for the electric field on or near the body.

  16. A 3D printed electromagnetic nonlinear vibration energy harvester

    NASA Astrophysics Data System (ADS)

    Constantinou, P.; Roy, S.

    2016-09-01

    A 3D printed electromagnetic vibration energy harvester is presented. The motion of the device is in-plane with the excitation vibrations, and this is enabled through the exploitation of a leaf isosceles trapezoidal flexural pivot topology. This topology is ideally suited for systems requiring restricted out-of-plane motion and benefits from being fabricated monolithically. This is achieved by 3D printing the topology with materials having a low flexural modulus. The presented system has a nonlinear softening spring response, as a result of designed magnetic force interactions. A discussion of fatigue performance is presented and it is suggested that whilst fabricating, the raster of the suspension element is printed perpendicular to the flexural direction and that the experienced stress is as low as possible during operation, to ensure longevity. A demonstrated power of ˜25 μW at 0.1 g is achieved and 2.9 mW is demonstrated at 1 g. The corresponding bandwidths reach up-to 4.5 Hz. The system’s corresponding power density of ˜0.48 mW cm-3 and normalised power integral density of 11.9 kg m-3 (at 1 g) are comparable to other in-plane systems found in the literature.

  17. 3D synthetic aperture for controlled-source electromagnetics

    NASA Astrophysics Data System (ADS)

    Knaak, Allison

    Locating hydrocarbon reservoirs has become more challenging with smaller, deeper or shallower targets in complicated environments. Controlled-source electromagnetics (CSEM), is a geophysical electromagnetic method used to detect and derisk hydrocarbon reservoirs in marine settings, but it is limited by the size of the target, low-spatial resolution, and depth of the reservoir. To reduce the impact of complicated settings and improve the detecting capabilities of CSEM, I apply synthetic aperture to CSEM responses, which virtually increases the length and width of the CSEM source by combining the responses from multiple individual sources. Applying a weight to each source steers or focuses the synthetic aperture source array in the inline and crossline directions. To evaluate the benefits of a 2D source distribution, I test steered synthetic aperture on 3D diffusive fields and view the changes with a new visualization technique. Then I apply 2D steered synthetic aperture to 3D noisy synthetic CSEM fields, which increases the detectability of the reservoir significantly. With more general weighting, I develop an optimization method to find the optimal weights for synthetic aperture arrays that adapts to the information in the CSEM data. The application of optimally weighted synthetic aperture to noisy, simulated electromagnetic fields reduces the presence of noise, increases detectability, and better defines the lateral extent of the target. I then modify the optimization method to include a term that minimizes the variance of random, independent noise. With the application of the modified optimization method, the weighted synthetic aperture responses amplifies the anomaly from the reservoir, lowers the noise floor, and reduces noise streaks in noisy CSEM responses from sources offset kilometers from the receivers. Even with changes to the location of the reservoir and perturbations to the physical properties, synthetic aperture is still able to highlight targets

  18. 3-D TECATE/BREW: Thermal, stress, and birefringent ray-tracing codes for solid-state laser design

    NASA Astrophysics Data System (ADS)

    Gelinas, R. J.; Doss, S. K.; Nelson, R. G.

    1994-07-01

    This report describes the physics, code formulations, and numerics that are used in the TECATE (totally Eulerian code for anisotropic thermo-elasticity) and BREW (birefringent ray-tracing of electromagnetic waves) codes for laser design. These codes resolve thermal, stress, and birefringent optical effects in 3-D stationary solid-state systems. This suite of three constituent codes is a package referred to as LASRPAK.

  19. RELAP5-3D code validation for RBMK phenomena

    SciTech Connect

    Fisher, J.E.

    1999-09-01

    The RELAP5-3D thermal-hydraulic code was assessed against Japanese Safety Experiment Loop (SEL) and Heat Transfer Loop (HTL) tests. These tests were chosen because the phenomena present are applicable to analyses of Russian RBMK reactor designs. The assessment cases included parallel channel flow fluctuation tests at reduced and normal water levels, a channel inlet pipe rupture test, and a high power, density wave oscillation test. The results showed that RELAP5-3D has the capability to adequately represent these RBMK-related phenomena.

  20. RELAP5-3D Code Validation for RBMK Phenomena

    SciTech Connect

    Fisher, James Ebberly

    1999-09-01

    The RELAP5-3D thermal-hydraulic code was assessed against Japanese Safety Experiment Loop (SEL) and Heat Transfer Loop (HTL) tests. These tests were chosen because the phenomena present are applicable to analyses of Russian RBMK reactor designs. The assessment cases included parallel channel flow fluctuation tests at reduced and normal water levels, a channel inlet pipe rupture test, and a high power, density wave oscillation test. The results showed that RELAP5-3D has the capability to adequately represent these RBMK-related phenomena.

  1. Development of 3D electromagnetic modeling tools for airborne vehicles

    NASA Technical Reports Server (NTRS)

    Volakis, John L.

    1992-01-01

    The main goal of this report is to advance the development of methodologies for scattering by airborne composite vehicles. Although the primary focus continues to be the development of a general purpose computer code for analyzing the entire structure as a single unit, a number of other tasks are also being pursued in parallel with this effort. One of these tasks discussed within is on new finite element formulations and mesh termination schemes. The goal here is to decrease computation time while retaining accuracy and geometric adaptability.The second task focuses on the application of wavelets to electromagnetics. Wavelet transformations are shown to be able to reduce a full matrix to a band matrix, thereby reducing the solutions memory requirements. Included within this document are two separate papers on finite element formulations and wavelets.

  2. VISRAD, 3-D Target Design and Radiation Simulation Code

    NASA Astrophysics Data System (ADS)

    Golovkin, Igor; Macfarlane, Joseph; Golovkina, Viktoriya

    2016-10-01

    The 3-D view factor code VISRAD is widely used in designing HEDP experiments at major laser and pulsed-power facilities, including NIF, OMEGA, OMEGA-EP, ORION, LMJ, Z, and PLX. It simulates target designs by generating a 3-D grid of surface elements, utilizing a variety of 3-D primitives and surface removal algorithms, and can be used to compute the radiation flux throughout the surface element grid by computing element-to-element view factors and solving power balance equations. Target set-up and beam pointing are facilitated by allowing users to specify positions and angular orientations using a variety of coordinates systems (e.g., that of any laser beam, target component, or diagnostic port). Analytic modeling for laser beam spatial profiles for OMEGA DPPs and NIF CPPs is used to compute laser intensity profiles throughout the grid of surface elements. We will discuss recent improvements to the software package and plans for future developments.

  3. CALTRANS: A parallel, deterministic, 3D neutronics code

    SciTech Connect

    Carson, L.; Ferguson, J.; Rogers, J.

    1994-04-01

    Our efforts to parallelize the deterministic solution of the neutron transport equation has culminated in a new neutronics code CALTRANS, which has full 3D capability. In this article, we describe the layout and algorithms of CALTRANS and present performance measurements of the code on a variety of platforms. Explicit implementation of the parallel algorithms of CALTRANS using both the function calls of the Parallel Virtual Machine software package (PVM 3.2) and the Meiko CS-2 tagged message passing library (based on the Intel NX/2 interface) are provided in appendices.

  4. Towards a 3D Space Radiation Transport Code

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.; Tripathl, R. K.; Cicomptta, F. A.; Heinbockel, J. H.; Tweed, J.

    2002-01-01

    High-speed computational procedures for space radiation shielding have relied on asymptotic expansions in terms of the off-axis scatter and replacement of the general geometry problem by a collection of flat plates. This type of solution was derived for application to human rated systems in which the radius of the shielded volume is large compared to the off-axis diffusion limiting leakage at lateral boundaries. Over the decades these computational codes are relatively complete and lateral diffusion effects are now being added. The analysis for developing a practical full 3D space shielding code is presented.

  5. Streamlining of the RELAP5-3D Code

    SciTech Connect

    Mesina, George L; Hykes, Joshua; Guillen, Donna Post

    2007-11-01

    RELAP5-3D is widely used by the nuclear community to simulate general thermal hydraulic systems and has proven to be so versatile that the spectrum of transient two-phase problems that can be analyzed has increased substantially over time. To accommodate the many new types of problems that are analyzed by RELAP5-3D, both the physics and numerical methods of the code have been continuously improved. In the area of computational methods and mathematical techniques, many upgrades and improvements have been made decrease code run time and increase solution accuracy. These include vectorization, parallelization, use of improved equation solvers for thermal hydraulics and neutron kinetics, and incorporation of improved library utilities. In the area of applied nuclear engineering, expanded capabilities include boron and level tracking models, radiation/conduction enclosure model, feedwater heater and compressor components, fluids and corresponding correlations for modeling Generation IV reactor designs, and coupling to computational fluid dynamics solvers. Ongoing and proposed future developments include improvements to the two-phase pump model, conversion to FORTRAN 90, and coupling to more computer programs. This paper summarizes the general improvements made to RELAP5-3D, with an emphasis on streamlining the code infrastructure for improved maintenance and development. With all these past, present and planned developments, it is necessary to modify the code infrastructure to incorporate modifications in a consistent and maintainable manner. Modifying a complex code such as RELAP5-3D to incorporate new models, upgrade numerics, and optimize existing code becomes more difficult as the code grows larger. The difficulty of this as well as the chance of introducing errors is significantly reduced when the code is structured. To streamline the code into a structured program, a commercial restructuring tool, FOR_STRUCT, was applied to the RELAP5-3D source files. The

  6. Preliminary investigations on 3D PIC simulation of DPHC structure using NEPTUNE3D code

    NASA Astrophysics Data System (ADS)

    Zhao, Hailong; Dong, Ye; Zhou, Haijing; Zou, Wenkang; Wang, Qiang

    2016-10-01

    Cubic region (34cm × 34cm × 18cm) including the double post-hole convolute (DPHC) structure was chosen to perform a series of fully 3D PIC simulations using NEPTUNE3D codes, massive data ( 200GB) could be acquired and solved in less than 5 hours. Cold-chamber tests were performed during which only cathode electron emission was considered without temperature rise or ion emission, current loss efficiency was estimated by comparisons between output magnetic field profiles with or without electron emission. PIC simulation results showed three stages of current transforming process with election emission in DPHC structure, the maximum ( 20%) current loss was 437kA at 15ns, while only 0.46% 0.48% was lost when driving current reached its peak. DPHC structure proved valuable functions during energy transform process in PTS facility, and NEPTUNE3D provided tools to explore this sophisticated physics. Project supported by the National Natural Science Foundation of China, Grant No. 11571293, 11505172.

  7. Axisymmetric Implementation for 3D-Based DSMC Codes

    NASA Technical Reports Server (NTRS)

    Stewart, Benedicte; Lumpkin, F. E.; LeBeau, G. J.

    2011-01-01

    The primary objective in developing NASA s DSMC Analysis Code (DAC) was to provide a high fidelity modeling tool for 3D rarefied flows such as vacuum plume impingement and hypersonic re-entry flows [1]. The initial implementation has been expanded over time to offer other capabilities including a novel axisymmetric implementation. Because of the inherently 3D nature of DAC, this axisymmetric implementation uses a 3D Cartesian domain and 3D surfaces. Molecules are moved in all three dimensions but their movements are limited by physical walls to a small wedge centered on the plane of symmetry (Figure 1). Unfortunately, far from the axis of symmetry, the cell size in the direction perpendicular to the plane of symmetry (the Z-direction) may become large compared to the flow mean free path. This frequently results in inaccuracies in these regions of the domain. A new axisymmetric implementation is presented which aims to solve this issue by using Bird s approach for the molecular movement while preserving the 3D nature of the DAC software [2]. First, the computational domain is similar to that previously used such that a wedge must still be used to define the inflow surface and solid walls within the domain. As before molecules are created inside the inflow wedge triangles but they are now rotated back to the symmetry plane. During the move step, molecules are moved in 3D but instead of interacting with the wedge walls, the molecules are rotated back to the plane of symmetry at the end of the move step. This new implementation was tested for multiple flows over axisymmetric shapes, including a sphere, a cone, a double cone and a hollow cylinder. Comparisons to previous DSMC solutions and experiments, when available, are made.

  8. 3D modelling of the electromagnetic response of geophysical targets using the FDTD method

    SciTech Connect

    Debroux, P.S.

    1996-05-01

    A publicly available and maintained electromagnetic finite-difference time domain (FDTD) code has been applied to the forward modelling of the response of 1D, 2D and 3D geophysical targets to a vertical magnetic dipole excitation. The FDTD method is used to analyze target responses in the 1 MHz to 100 MHz range, where either conduction or displacement currents may have the controlling role. The response of the geophysical target to the excitation is presented as changes in the magnetic field ellipticity. The results of the FDTD code compare favorably with previously published integral equation solutions of the response of 1D targets, and FDTD models calculated with different finite-difference cell sizes are compared to find the effect of model discretization on the solution. The discretization errors, calculated as absolute error in ellipticity, are presented for the different ground geometry models considered, and are, for the most part, below 10% of the integral equation solutions. Finally, the FDTD code is used to calculate the magnetic ellipticity response of a 2D survey and a 3D sounding of complicated geophysical targets. The response of these 2D and 3D targets are too complicated to be verified with integral equation solutions, but show the proper low- and high-frequency responses.

  9. MOM3D/EM-ANIMATE - MOM3D WITH ANIMATION CODE

    NASA Technical Reports Server (NTRS)

    Shaeffer, J. F.

    1994-01-01

    MOM3D (LAR-15074) is a FORTRAN method-of-moments electromagnetic analysis algorithm for open or closed 3-D perfectly conducting or resistive surfaces. Radar cross section with plane wave illumination is the prime analysis emphasis; however, provision is also included for local port excitation for computing antenna gain patterns and input impedances. The Electric Field Integral Equation form of Maxwell's equations is solved using local triangle couple basis and testing functions with a resultant system impedance matrix. The analysis emphasis is not only for routine RCS pattern predictions, but also for phenomenological diagnostics: bistatic imaging, currents, and near scattered/total electric fields. The images, currents, and near fields are output in form suitable for animation. MOM3D computes the full backscatter and bistatic radar cross section polarization scattering matrix (amplitude and phase), body currents and near scattered and total fields for plane wave illumination. MOM3D also incorporates a new bistatic k space imaging algorithm for computing down range and down/cross range diagnostic images using only one matrix inversion. MOM3D has been made memory and cpu time efficient by using symmetric matrices, symmetric geometry, and partitioned fixed and variable geometries suitable for design iteration studies. MOM3D may be run interactively or in batch mode on 486 IBM PCs and compatibles, UNIX workstations or larger computers. A 486 PC with 16 megabytes of memory has the potential to solve a 30 square wavelength (containing 3000 unknowns) symmetric configuration. Geometries are described using a triangular mesh input in the form of a list of spatial vertex points and a triangle join connection list. The EM-ANIMATE (LAR-15075) program is a specialized visualization program that displays and animates the near-field and surface-current solutions obtained from an electromagnetics program, in particular, that from MOM3D. The EM-ANIMATE program is windows based and

  10. FARGO3D: A NEW GPU-ORIENTED MHD CODE

    SciTech Connect

    Benitez-Llambay, Pablo; Masset, Frédéric S. E-mail: masset@icf.unam.mx

    2016-03-15

    We present the FARGO3D code, recently publicly released. It is a magnetohydrodynamics code developed with special emphasis on the physics of protoplanetary disks and planet–disk interactions, and parallelized with MPI. The hydrodynamics algorithms are based on finite-difference upwind, dimensionally split methods. The magnetohydrodynamics algorithms consist of the constrained transport method to preserve the divergence-free property of the magnetic field to machine accuracy, coupled to a method of characteristics for the evaluation of electromotive forces and Lorentz forces. Orbital advection is implemented, and an N-body solver is included to simulate planets or stars interacting with the gas. We present our implementation in detail and present a number of widely known tests for comparison purposes. One strength of FARGO3D is that it can run on either graphical processing units (GPUs) or central processing units (CPUs), achieving large speed-up with respect to CPU cores. We describe our implementation choices, which allow a user with no prior knowledge of GPU programming to develop new routines for CPUs, and have them translated automatically for GPUs.

  11. Depth estimation from multiple coded apertures for 3D interaction

    NASA Astrophysics Data System (ADS)

    Suh, Sungjoo; Choi, Changkyu; Park, Dusik

    2013-09-01

    In this paper, we propose a novel depth estimation method from multiple coded apertures for 3D interaction. A flat panel display is transformed into lens-less multi-view cameras which consist of multiple coded apertures. The sensor panel behind the display captures the scene in front of the display through the imaging pattern of the modified uniformly redundant arrays (MURA) on the display panel. To estimate the depth of an object in the scene, we first generate a stack of synthetically refocused images at various distances by using the shifting and averaging approach for the captured coded images. And then, an initial depth map is obtained by applying a focus operator to a stack of the refocused images for each pixel. Finally, the depth is refined by fitting a parametric focus model to the response curves near the initial depth estimates. To demonstrate the effectiveness of the proposed algorithm, we construct an imaging system to capture the scene in front of the display. The system consists of a display screen and an x-ray detector without a scintillator layer so as to act as a visible sensor panel. Experimental results confirm that the proposed method accurately determines the depth of an object including a human hand in front of the display by capturing multiple MURA coded images, generating refocused images at different depth levels, and refining the initial depth estimates.

  12. The CONV-3D code for DNS CFD calculation

    NASA Astrophysics Data System (ADS)

    Chudanov, Vladimir; ALCF ThermHydraX Team

    2014-03-01

    The CONV-3D code for DNS CFD calculation of thermal and hydrodynamics on Fast Reactor with use of supercomputers is developed. This code is highly effective in a scalability at the high performance computers such as ``Chebyshev'', ``Lomonosov'' (Moscow State University, Russia), Blue Gene/Q(ALCF MIRA, ANL). The scalability is reached up to 106 processors. The code was validated on a series of the well known tests in a wide range of Rayleigh (106-1016) and Reynolds (103-105. Such code was validated on the blind tests OECD/NEA of the turbulent intermixing in horizontal subchannels of the fuel assembly at normal pressure and temperature (Matis-H), of the flows in T-junction and the report IBRAE/ANL was published. The good coincidence of numerical predictions with experimental data was reached, that specifies applicability of the developed approach for a prediction of thermal and hydrodynamics in a boundary layer at small Prandtl that is characteristic of the liquid metal reactors. Project Name: ThermHydraX. Project Title: U.S.-Russia Collaboration on Cross-Verification and Validation in Thermal Hydraulics.

  13. RHALE: A 3-D MMALE code for unstructured grids

    SciTech Connect

    Peery, J.S.; Budge, K.G.; Wong, M.K.W.; Trucano, T.G.

    1993-08-01

    This paper describes RHALE, a multi-material arbitrary Lagrangian-Eulerian (MMALE) shock physics code. RHALE is the successor to CTH, Sandia`s 3-D Eulerian shock physics code, and will be capable of solving problems that CTH cannot adequately address. We discuss the Lagrangian solid mechanics capabilities of RHALE, which include arbitrary mesh connectivity, superior artificial viscosity, and improved material models. We discuss the MMALE algorithms that have been extended for arbitrary grids in both two- and three-dimensions. The MMALE addition to RHALE provides the accuracy of a Lagrangian code while allowing a calculation to proceed under very large material distortions. Coupling an arbitrary quadrilateral or hexahedral grid to the MMALE solution facilitates modeling of complex shapes with a greatly reduced number of computational cells. RHALE allows regions of a problem to be modeled with Lagrangian, Eulerian or ALE meshes. In addition, regions can switch from Lagrangian to ALE to Eulerian based on user input or mesh distortion. For ALE meshes, new node locations are determined with a variety of element based equipotential schemes. Element quantities are advected with donor, van Leer, or Super-B algorithms. Nodal quantities are advected with the second order SHALE or HIS algorithms. Material interfaces are determined with a modified Young`s high resolution interface tracker or the SLIC algorithm. RHALE has been used to model many problems of interest to the mechanics, hypervelocity impact, and shock physics communities. Results of a sampling of these problems are presented in this paper.

  14. Image sequence coding using 3D scene models

    NASA Astrophysics Data System (ADS)

    Girod, Bernd

    1994-09-01

    The implicit and explicit use of 3D models for image sequence coding is discussed. For implicit use, a 3D model can be incorporated into motion compensating prediction. A scheme that estimates the displacement vector field with a rigid body motion constraint by recovering epipolar lines from an unconstrained displacement estimate and then repeating block matching along the epipolar line is proposed. Experimental results show that an improved displacement vector field can be obtained with a rigid body motion constraint. As an example for explicit use, various results with a facial animation model for videotelephony are discussed. A 13 X 16 B-spline mask can be adapted automatically to individual faces and is used to generate facial expressions based on FACS. A depth-from-defocus range camera suitable for real-time facial motion tracking is described. Finally, the real-time facial animation system `Traugott' is presented that has been used to generate several hours of broadcast video. Experiments suggest that a videophone system based on facial animation might require a transmission bitrate of 1 kbit/s or below.

  15. Development of 3D electromagnetic modeling tools for airborne vehicles

    NASA Technical Reports Server (NTRS)

    Volakis, John L.

    1992-01-01

    The main goal of this project is to develop methodologies for scattering by airborne composite vehicles. Although our primary focus continues to be the development of a general purpose code for analyzing the entire structure as a single unit, a number of other tasks are also pursued in parallel with this effort. These tasks are important in testing the overall approach and in developing suitable models for materials coatings, junctions and, more generally, in assessing the effectiveness of the various parts comprising the final code. Here, we briefly discuss our progress on the five different tasks which were pursued during this period. Our progress on each of these tasks is described in the detailed reports (listed at the end of this report) and the memoranda included. The first task described below is, of course, the core of this project and deals with the development of the overall code. Undoubtedly, it is the outcome of the research which was funded by NASA-Ames and the Navy over the past three years. During this year we developed the first finite element code for scattering by structures of arbitrary shape and composition. The code employs a new absorbing boundary condition which allows termination of the finite element mesh only 0.3 lambda from the outer surface of the target. This leads to a remarkable reduction of the mesh size and is a unique feature of the code. Other unique features of this code include capabilities to model resistive sheets, impedance sheets and anisotropic materials. This last capability is the latest feature of the code and is still under development. The code has been extensively validated for a number of composite geometries and some examples are given. The validation of the code is still in progress for anisotropic and larger non-metallic geometries and cavities. The developed finite element code is based on a Galerkin's formulation and employs edge-based tetrahedral elements for discretizing the dielectric sections and the region

  16. Invariant superoscillatory electromagnetic fields in 3D-space

    NASA Astrophysics Data System (ADS)

    Makris, K. G.; Papazoglou, D. G.; Tzortzakis, S.

    2017-01-01

    We derive exact solutions of Maxwell’s equations based on superoscillatory superpositions of vectorial Bessel beams. These novel beams are diffraction-free and can support subwavelength features in their transverse electromagnetic fields, without the presence of any evanescent waves. These features can be propagated into the far field. Approximate solutions in closed form are also derived based on asymptotic expansions of Bessel functions for simple prescribed subwavelength patterns. The superoscillatory characteristics of both electric, magnetic field components (transverse and longitudinal), and the Poynting vector, as well as, the effect of nonparaxiality are systematically investigated.

  17. EM modeling for GPIR using 3D FDTD modeling codes

    SciTech Connect

    Nelson, S.D.

    1994-10-01

    An analysis of the one-, two-, and three-dimensional electrical characteristics of structural cement and concrete is presented. This work connects experimental efforts in characterizing cement and concrete in the frequency and time domains with the Finite Difference Time Domain (FDTD) modeling efforts of these substances. These efforts include Electromagnetic (EM) modeling of simple lossless homogeneous materials with aggregate and targets and the modeling dispersive and lossy materials with aggregate and complex target geometries for Ground Penetrating Imaging Radar (GPIR). Two- and three-dimensional FDTD codes (developed at LLNL) where used for the modeling efforts. Purpose of the experimental and modeling efforts is to gain knowledge about the electrical properties of concrete typically used in the construction industry for bridges and other load bearing structures. The goal is to optimize the performance of a high-sample-rate impulse radar and data acquisition system and to design an antenna system to match the characteristics of this material. Results show agreement to within 2 dB of the amplitudes of the experimental and modeled data while the frequency peaks correlate to within 10% the differences being due to the unknown exact nature of the aggregate placement.

  18. Modeling electromagnetic rail launchers at speed using 3D finite elements

    SciTech Connect

    Rodger, D.; Leonard, P.J.; Eastham, J.F. )

    1991-01-01

    In this paper a new finite element technique for modelling 3D transient eddy currents in moving conductors is described. This has been implemented in the MEGA software package for 2 and 3D electromagnetic field analysis. The application of the technique to railgun launchers is illustrated.

  19. Rapid Prototyping across the Spectrum: RF to Optical 3D Electromagnetic Structures

    DTIC Science & Technology

    2015-11-17

    fabricated using 3D printer . The fill factor decreases radially outwards and the voids are visible in the unit cells as you approach the periphery of the...with thin walls) [29]. Figure 6: Examples of lenses fabricated with AM (a) GRIN lens fabricated using 3D printer . The fill factor decreases...AFRL-RW-EG-TP-2015-002 Rapid Prototyping across the Spectrum: RF to Optical 3D Electromagnetic Structures Jeffery W. Allen Monica S. Allen Brett

  20. 3D neutronic codes coupled with thermal-hydraulic system codes for PWR, and BWR and VVER reactors

    SciTech Connect

    Langenbuch, S.; Velkov, K.; Lizorkin, M.

    1997-07-01

    This paper describes the objectives of code development for coupling 3D neutronics codes with thermal-hydraulic system codes. The present status of coupling ATHLET with three 3D neutronics codes for VVER- and LWR-reactors is presented. After describing the basic features of the 3D neutronic codes BIPR-8 from Kurchatov-Institute, DYN3D from Research Center Rossendorf and QUABOX/CUBBOX from GRS, first applications of coupled codes for different transient and accident scenarios are presented. The need of further investigations is discussed.

  1. A Magnetic Diagnostic Code for 3D Fusion Equilibria

    SciTech Connect

    Samuel A. Lazerson, S. Sakakibara and Y. Suzuki

    2013-03-12

    A synthetic magnetic diagnostics code for fusion equilibria is presented. This code calculates the response of various magnetic diagnostics to the equilibria produced by the VMEC and PIES codes. This allows for treatment of equilibria with both good nested flux surfaces and those with stochastic regions. DIAGNO v2.0 builds upon previous codes through the implementation of a virtual casing principle. The code is validated against a vacuum shot on the Large Helical Device (LHD) where the vertical field was ramped. As an exercise of the code, the diagnostic response for various equilibria are calculated on the LHD.

  2. Nonlinear 3D MHD verification study: SpeCyl and PIXIE3D codes for RFP and Tokamak plasmas

    NASA Astrophysics Data System (ADS)

    Bonfiglio, D.; Cappello, S.; Chacon, L.

    2010-11-01

    A strong emphasis is presently placed in the fusion community on reaching predictive capability of computational models. An essential requirement of such endeavor is the process of assessing the mathematical correctness of computational tools, termed verification [1]. We present here a successful nonlinear cross-benchmark verification study between the 3D nonlinear MHD codes SpeCyl [2] and PIXIE3D [3]. Excellent quantitative agreement is obtained in both 2D and 3D nonlinear visco-resistive dynamics for reversed-field pinch (RFP) and tokamak configurations [4]. RFP dynamics, in particular, lends itself as an ideal non trivial test-bed for 3D nonlinear verification. Perspectives for future application of the fully-implicit parallel code PIXIE3D to RFP physics, in particular to address open issues on RFP helical self-organization, will be provided. [4pt] [1] M. Greenwald, Phys. Plasmas 17, 058101 (2010) [0pt] [2] S. Cappello and D. Biskamp, Nucl. Fusion 36, 571 (1996) [0pt] [3] L. Chac'on, Phys. Plasmas 15, 056103 (2008) [0pt] [4] D. Bonfiglio, L. Chac'on and S. Cappello, Phys. Plasmas 17 (2010)

  3. Recent Improvements To The RELAP5-3D Code

    SciTech Connect

    Richard A. Riemke; Paul D. Bayless; S. Michael Modro

    2006-06-01

    The RELAP5-3D computer program has been recently improved. Changes were made as follows: (1) heat structures are allowed to be decoupled from hydrodynamic components, (2) built-in material properties for heat structures have been made consistent with those in MATPRO and the Nuclear Systems Materials Handbook (they are now documented in the RELAP5-3D manual, (3) Schrock's flow quality correlation is now used for a downward oriented junction from a horizontal volume for the stratification entrainment/pullthrough model.

  4. ICRF Antenna Characteristics and Comparison with 3-D Code Calculation in the LHD

    SciTech Connect

    Mutoh, T.; Kasahara, H.; Seki, T.; Saito, K.; Kumazawa, R.; Shimpo, F.; Nomura, G.

    2009-11-26

    The plasma coupling characteristics and local heat spots of an ion cyclotron range of frequencies (ICRF) antenna in the Large Helical Device (LHD) are compared with the results of 3-D computing simulator code calculation. We studied several dependences of antenna loading resistances with plasma experimentally and observed a clear relation between the maximum injection power and the loading resistance. Realistic three-dimensional configuration of the ICRF antenna was taken into account to simulate the coupling characteristics and the local heat absorption near the ICRF antenna, which has a helically twisted geometry in the LHD. The electromagnetic field distribution and the current distribution on the antenna strap were calculated. We compared the RF absorption distribution on the antenna structure with the temperature rise during steady state operation and found that the temperature rise was well explained by comparing with the model simulation.

  5. 3D LBFGS inversion of controlled source extremely low frequency electromagnetic data

    NASA Astrophysics Data System (ADS)

    Cao, Meng; Tan, Han-Dong; Wang, Kun-Peng

    2016-12-01

    The controlled source extremely low frequency (CSELF) electromagnetic method is characterized by extremely long and powerful sources and a huge measurement range. Its electromagnetic field can therefore be affected by the ionosphere and displacement current. Research on 3D forward modeling and inversion of CSELF electromagnetic data is currently in its infancy. This paper makes exploratory attempts to firstly calculate the 1D extremely low frequency electromagnetic field under ionosphere-air-earth coupling circumstances, and secondly analyze the propagation characteristics of the background electromagnetic field. The 3D staggered-grid finite difference scheme for solving for the secondary electric field is adopted and incorporated with the 1D modeling algorithm to complete 3D forward modeling. Considering that surveys can be carried out in the near field and transition zone for lower frequencies, the 3D Limited-memory Broyden-Fletcher-Goldfarb-Shanno (LBFGS) inversion of CSELF electromagnetic data is presented (in which the sources, or primary fields, are included), with the aim of directly inverting the impedance data, regardless of where it is acquired. Derivation of the objective functional gradient is the core component in the inversion. Synthetic tests indicate that the well-chosen approximation to the Hessian can significantly speed up the inversion. The model responses corresponding to the coexistence of conductive and resistive blocks show that the off-diagonal components of tensor impedance are much more sensitive to the resistivity variation than the diagonal components. In comparison with conventional scalar inversion, tensor inversion is superior in the recoveries of electric anomalies and background resistivity.

  6. Verification and Validation of the k-kL Turbulence Model in FUN3D and CFL3D Codes

    NASA Technical Reports Server (NTRS)

    Abdol-Hamid, Khaled S.; Carlson, Jan-Renee; Rumsey, Christopher L.

    2015-01-01

    The implementation of the k-kL turbulence model using multiple computational uid dy- namics (CFD) codes is reported herein. The k-kL model is a two-equation turbulence model based on Abdol-Hamid's closure and Menter's modi cation to Rotta's two-equation model. Rotta shows that a reliable transport equation can be formed from the turbulent length scale L, and the turbulent kinetic energy k. Rotta's equation is well suited for term-by-term mod- eling and displays useful features compared to other two-equation models. An important di erence is that this formulation leads to the inclusion of higher-order velocity derivatives in the source terms of the scale equations. This can enhance the ability of the Reynolds- averaged Navier-Stokes (RANS) solvers to simulate unsteady ows. The present report documents the formulation of the model as implemented in the CFD codes Fun3D and CFL3D. Methodology, veri cation and validation examples are shown. Attached and sepa- rated ow cases are documented and compared with experimental data. The results show generally very good comparisons with canonical and experimental data, as well as matching results code-to-code. The results from this formulation are similar or better than results using the SST turbulence model.

  7. Benchmark of Different Electromagnetic Codes for the High Frequency Calculation

    SciTech Connect

    Kai Tian, Haipeng Wang, Frank Marhauser, Guangfeng Cheng, Chuandong Zhou

    2009-05-01

    In this paper, we present benchmarking results for highclass 3D electromagnetic (EM) codes in designing RF cavities today. These codes include Omega3P [1], VORPAL [2], CST Microwave Studio [3], Ansoft HFSS [4], and ANSYS [5]. Two spherical cavities are selected as the benchmark models. We have compared not only the accuracy of resonant frequencies, but also that of surface EM fields, which are critical for superconducting RF cavities. By removing degenerated modes, we calculate all the resonant modes up to 10 GHz with similar mesh densities, so that the geometry approximation and field interpolation error related to the wavelength can be observed.

  8. 3D unstructured-mesh radiation transport codes

    SciTech Connect

    Morel, J.

    1997-12-31

    Three unstructured-mesh radiation transport codes are currently being developed at Los Alamos National Laboratory. The first code is ATTILA, which uses an unstructured tetrahedral mesh in conjunction with standard Sn (discrete-ordinates) angular discretization, standard multigroup energy discretization, and linear-discontinuous spatial differencing. ATTILA solves the standard first-order form of the transport equation using source iteration in conjunction with diffusion-synthetic acceleration of the within-group source iterations. DANTE is designed to run primarily on workstations. The second code is DANTE, which uses a hybrid finite-element mesh consisting of arbitrary combinations of hexahedra, wedges, pyramids, and tetrahedra. DANTE solves several second-order self-adjoint forms of the transport equation including the even-parity equation, the odd-parity equation, and a new equation called the self-adjoint angular flux equation. DANTE also offers three angular discretization options: $S{_}n$ (discrete-ordinates), $P{_}n$ (spherical harmonics), and $SP{_}n$ (simplified spherical harmonics). DANTE is designed to run primarily on massively parallel message-passing machines, such as the ASCI-Blue machines at LANL and LLNL. The third code is PERICLES, which uses the same hybrid finite-element mesh as DANTE, but solves the standard first-order form of the transport equation rather than a second-order self-adjoint form. DANTE uses a standard $S{_}n$ discretization in angle in conjunction with trilinear-discontinuous spatial differencing, and diffusion-synthetic acceleration of the within-group source iterations. PERICLES was initially designed to run on workstations, but a version for massively parallel message-passing machines will be built. The three codes will be described in detail and computational results will be presented.

  9. Numerical modelling of gravel unconstrained flow experiments with the DAN3D and RASH3D codes

    NASA Astrophysics Data System (ADS)

    Sauthier, Claire; Pirulli, Marina; Pisani, Gabriele; Scavia, Claudio; Labiouse, Vincent

    2015-12-01

    Landslide continuum dynamic models have improved considerably in the last years, but a consensus on the best method of calibrating the input resistance parameter values for predictive analyses has not yet emerged. In the present paper, numerical simulations of a series of laboratory experiments performed at the Laboratory for Rock Mechanics of the EPF Lausanne were undertaken with the RASH3D and DAN3D numerical codes. They aimed at analysing the possibility to use calibrated ranges of parameters (1) in a code different from that they were obtained from and (2) to simulate potential-events made of a material with the same characteristics as back-analysed past-events, but involving a different volume and propagation path. For this purpose, one of the four benchmark laboratory tests was used as past-event to calibrate the dynamic basal friction angle assuming a Coulomb-type behaviour of the sliding mass, and this back-analysed value was then used to simulate the three other experiments, assumed as potential-events. The computational findings show good correspondence with experimental results in terms of characteristics of the final deposits (i.e., runout, length and width). Furthermore, the obtained best fit values of the dynamic basal friction angle for the two codes turn out to be close to each other and within the range of values measured with pseudo-dynamic tilting tests.

  10. 1d, 2d, and 3d periodic structures: Electromagnetic characterization, design, and measurement

    NASA Astrophysics Data System (ADS)

    Brockett, Timothy John

    Periodic structures have many useful applications in electromagnetics including phased arrays, frequency selective surfaces, and absorbing interfaces. Their unique properties can be used to provide increased performance in antenna gain, electromagnetic propagation, and electromagnetic absorption. In antenna arrays, repeating elements create a larger eective aperture, increasing the gain of the antenna and the ability to scan the direction of the main beam. Three-dimensional periodic structures, such as an array of shaped pillars such as columns, cones, or prisms have the potential of improving electromagnetic absorption, improving performance in applications such as solar cell eciency and absorbing interfaces. Furthermore, research into periodic structures is a continuing endeavor where novel approaches and analysis in appropriate applications can be sought. This dissertation will address the analysis, diagnostics, and enhancement of 1D, 2D, and 3D periodic structures for antenna array applications and solar cell technology. In particular, a unique approach to array design will be introduced to prevent the appearance of undesirable grating lobes in large antenna arrays that employ subarrays. This approach, named the distortion diagnostic procedure, can apply directly to 1D and 2D periodic structures in the form of planar antenna arrays. Interesting corollaries included here are developments in millimeter-wave antenna measurements including spiral planar scanning, phaseless measurements, and addressing antennas that feature an internal source. Finally, analysis and enhancement of 3D periodic structures in nanostructure photovoltaic arrays and absorbing interfaces will be examined for their behavior and basic operation in regards to improved absorption of electromagnetic waves.

  11. ROAR: A 3-D tethered rocket simulation code

    SciTech Connect

    York, A.R. II; Ludwigsen, J.S.

    1992-04-01

    A high-velocity impact testing technique, utilizing a tethered rocket, is being developed at Sandia National Laboratories. The technique involves tethering a rocket assembly to a pivot location and flying it in a semicircular trajectory to deliver the rocket and payload to an impact target location. Integral to developing this testing technique is the parallel development of accurate simulation models. An operational computer code, called ROAR (Rocket-on-a-Rope), has been developed to simulate the three-dimensional transient dynamic behavior of the tether and motor/payload assembly. This report presents a discussion of the parameters modeled, the governing set of equations, the through-time integration scheme, and the input required to set up a model. Also included is a sample problem and a comparison with experimental results.

  12. Using the CAVE virtual-reality environment as an aid to 3-D electromagnetic field computation

    SciTech Connect

    Turner, L.R.; Levine, D.; Huang, M.; Papka, M; Kettunen, L.

    1995-08-01

    One of the major problems in three-dimensional (3-D) field computation is visualizing the resulting 3-D field distributions. A virtual-reality environment, such as the CAVE, (CAVE Automatic Virtual Environment) is helping to overcome this problem, thus making the results of computation more usable for designers and users of magnets and other electromagnetic devices. As a demonstration of the capabilities of the CAVE, the elliptical multipole wiggler (EMW), an insertion device being designed for the Advanced Photon Source (APS) now being commissioned at Argonne National Laboratory (ANL), wa made visible, along with its fields and beam orbits. Other uses of the CAVE in preprocessing and postprocessing computation for electromagnetic applications are also discussed.

  13. PEGASUS. 3D Direct Simulation Monte Carlo Code Which Solves for Geometrics

    SciTech Connect

    Bartel, T.J.

    1998-12-01

    Pegasus is a 3D Direct Simulation Monte Carlo Code which solves for geometries which can be represented by bodies of revolution. Included are all the surface chemistry enhancements in the 2D code Icarus as well as a real vacuum pump model. The code includes multiple species transport.

  14. 3D Direct Simulation Monte Carlo Code Which Solves for Geometrics

    SciTech Connect

    Bartel, Timothy J.

    1998-01-13

    Pegasus is a 3D Direct Simulation Monte Carlo Code which solves for geometries which can be represented by bodies of revolution. Included are all the surface chemistry enhancements in the 2D code Icarus as well as a real vacuum pump model. The code includes multiple species transport.

  15. Electromagnetic Response Inversion for a 3D Distribution of Conductivity/Dielect

    SciTech Connect

    Newman, Gregory

    2001-10-24

    NLCGCS inverts electromagnetic responses for a 3D distribution of electrical conductivity and dielectric permittivity within the earth for geophysical applications using single processor computers. The software comes bundled with a graphical user interface to aid in model construction and analysis and viewing of earth images. The solution employs both dipole and finite size source configurations for harmonic oscillatory sources. A new nonlinear preconditioner is included in the solution to speed up solution convergence.

  16. Joint source/channel coding for prioritized wireless transmission of multiple 3-D regions of interest in 3-D medical imaging data.

    PubMed

    Sanchez, V

    2013-02-01

    This paper presents a 3-D medical image coding method featuring two major improvements to previous work on 3-D region of interest (RoI) coding for telemedicine applications. Namely, 1) a data prioritization scheme that allows coding of multiple 3-D-RoIs; and 2) a joint/source channel coding scheme that allows prioritized transmission of multiple 3-D-RoIs over wireless channels. The method, which is based on the 3-D integer wavelet transform and embedded block coding with optimized truncation with 3-D context modeling, generates scalable and error-resilient bit streams with 3-D-RoI decoding capabilities. Coding of multiple 3-D-RoIs is attained by prioritizing the wavelet-transformed data according to a Gaussian mixed distribution, whereas error resiliency is attained by employing the error correction capabilities of rate-compatible punctured turbo codes. The robustness of the proposed method is evaluated for transmission of real 3-D medical images over Rayleigh-fading channels with a priori knowledge of the channel condition. Evaluation results show that the proposed coding method provides a superior performance compared to equal error protection and unequal error protection techniques.

  17. Finite-Difference Algorithm for Simulating 3D Electromagnetic Wavefields in Conductive Media

    NASA Astrophysics Data System (ADS)

    Aldridge, D. F.; Bartel, L. C.; Knox, H. A.

    2013-12-01

    Electromagnetic (EM) wavefields are routinely used in geophysical exploration for detection and characterization of subsurface geological formations of economic interest. Recorded EM signals depend strongly on the current conductivity of geologic media. Hence, they are particularly useful for inferring fluid content of saturated porous bodies. In order to enhance understanding of field-recorded data, we are developing a numerical algorithm for simulating three-dimensional (3D) EM wave propagation and diffusion in heterogeneous conductive materials. Maxwell's equations are combined with isotropic constitutive relations to obtain a set of six, coupled, first-order partial differential equations governing the electric and magnetic vectors. An advantage of this system is that it does not contain spatial derivatives of the three medium parameters electric permittivity, magnetic permeability, and current conductivity. Numerical solution methodology consists of explicit, time-domain finite-differencing on a 3D staggered rectangular grid. Temporal and spatial FD operators have order 2 and N, where N is user-selectable. We use an artificially-large electric permittivity to maximize the FD timestep, and thus reduce execution time. For the low frequencies typically used in geophysical exploration, accuracy is not unduly compromised. Grid boundary reflections are mitigated via convolutional perfectly matched layers (C-PMLs) imposed at the six grid flanks. A shared-memory-parallel code implementation via OpenMP directives enables rapid algorithm execution on a multi-thread computational platform. Good agreement is obtained in comparisons of numerically-generated data with reference solutions. EM wavefields are sourced via point current density and magnetic dipole vectors. Spatially-extended inductive sources (current carrying wire loops) are under development. We are particularly interested in accurate representation of high-conductivity sub-grid-scale features that are common

  18. Quantitative 3D electromagnetic field determination of 1D nanostructures from single projection

    SciTech Connect

    Phatak, Charudatta; Knoop, Ludvig de; Houdellier, Florent; Gatel, Christophe; Hytch, Martin J.; Masseboeuf, Aurelien

    2016-03-10

    One-dimensional (1D) nanostructures have been regarded as the most promising building blocks for nanoelectronics and nanocomposite material systems as well as for alternative energy applications. Although they result in confinement of a material, their properties and interactions with other nanostructures are still very much three-dimensional (3D) in nature. In this work, we present a novel method for quantitative determination of the 3D electromagnetic fields in and around 1D nanostructures using a single electron wave phase image, thereby eliminating the cumbersome acquisition of tomographic data. Using symmetry arguments, we have reconstructed the 3D magnetic field of a nickel nanowire as well as the 3D electric field around a carbon nanotube field emitter, from one single projection. The accuracy of quantitative values determined here is shown to be a better fit to the physics at play than the value obtained by conventional analysis. Furthermore the 3D reconstructions can then directly be visualized and used in the design of functional 3D architectures built using 1D nanostructures.

  19. Quantitative 3D electromagnetic field determination of 1D nanostructures from single projection

    DOE PAGES

    Phatak, Charudatta; Knoop, Ludvig de; Houdellier, Florent; ...

    2016-03-10

    One-dimensional (1D) nanostructures have been regarded as the most promising building blocks for nanoelectronics and nanocomposite material systems as well as for alternative energy applications. Although they result in confinement of a material, their properties and interactions with other nanostructures are still very much three-dimensional (3D) in nature. In this work, we present a novel method for quantitative determination of the 3D electromagnetic fields in and around 1D nanostructures using a single electron wave phase image, thereby eliminating the cumbersome acquisition of tomographic data. Using symmetry arguments, we have reconstructed the 3D magnetic field of a nickel nanowire as wellmore » as the 3D electric field around a carbon nanotube field emitter, from one single projection. The accuracy of quantitative values determined here is shown to be a better fit to the physics at play than the value obtained by conventional analysis. Furthermore the 3D reconstructions can then directly be visualized and used in the design of functional 3D architectures built using 1D nanostructures.« less

  20. Quantitative 3D electromagnetic field determination of 1D nanostructures from single projection

    SciTech Connect

    Phatak, C.; Knoop, L. de; Houdellier, F.; Gatel, C.; Hÿtch, M. J.; Masseboeuf, A.

    2016-05-01

    One-dimensional (1D) nanostructures have been regarded as the most promising building blocks for nanoelectronics and nanocomposite material systems as well as for alternative energy applications. Although they result in confinement of a material, their properties and interactions with other nanostructures are still very much three-dimensional (3D) in nature. In this work, we present a novel method for quantitative determination of the 3D electromagnetic fields in and around 1D nanostructures using a single electron wave phase image, thereby eliminating the cumbersome acquisition of tomographic data. Using symmetry arguments, we have reconstructed the 3D magnetic field of a nickel nanowire as well as the 3D electric field around a carbon nanotube field emitter, from one single projection. The accuracy of quantitative values determined here is shown to be a better fit to the physics at play than the value obtained by conventional analysis. Moreover the 3D reconstructions can then directly be visualized and used in the design of functional 3D architectures built using 1D nanostructures.

  1. Electromagnetic Gun Circuit Analysis Code (EGCAC)

    NASA Astrophysics Data System (ADS)

    Rolader, Glenn E.; Thornhill, Lindsey D.; Batteh, Jad H.; Scanlon, James J., III

    1993-01-01

    This paper describes a system engineering code that simulates the performance of a railgun/power supply system. The code, named EGCAC (Electromagnetic Gun Circuit Analysis Code), accounts for many performance degrading effects including viscous drag on the armature, viscous drag on the gas being pushed in front of the projectile, entrained gas that must be accelerated in front of the projectile, time-dependent rail resistance, armature resistance, system resistance, and ablation drag. EGCAC has been utilized to predict railgun performance up to a velocity of approximately 4 km/s for experiments at several laboratories. In this paper, the theory of EGCAC is described, and sample calculations are presented.

  2. 3-D field computation: The near-triumph of commerical codes

    SciTech Connect

    Turner, L.R.

    1995-07-01

    In recent years, more and more of those who design and analyze magnets and other devices are using commercial codes rather than developing their own. This paper considers the commercial codes and the features available with them. Other recent trends with 3-D field computation include parallel computation and visualization methods such as virtual reality systems.

  3. Lossy to lossless object-based coding of 3-D MRI data.

    PubMed

    Menegaz, Gloria; Thiran, Jean-Philippe

    2002-01-01

    We propose a fully three-dimensional (3-D) object-based coding system exploiting the diagnostic relevance of the different regions of the volumetric data for rate allocation. The data are first decorrelated via a 3-D discrete wavelet transform. The implementation via the lifting steps scheme allows to map integer-to-integer values, enabling lossless coding, and facilitates the definition of the object-based inverse transform. The coding process assigns disjoint segments of the bitstream to the different objects, which can be independently accessed and reconstructed at any up-to-lossless quality. Two fully 3-D coding strategies are considered: embedded zerotree coding (EZW-3D) and multidimensional layered zero coding (MLZC), both generalized for region of interest (ROI)-based processing. In order to avoid artifacts along region boundaries, some extra coefficients must be encoded for each object. This gives rise to an overheading of the bitstream with respect to the case where the volume is encoded as a whole. The amount of such extra information depends on both the filter length and the decomposition depth. The system is characterized on a set of head magnetic resonance images. Results show that MLZC and EZW-3D have competitive performances. In particular, the best MLZC mode outperforms the others state-of-the-art techniques on one of the datasets for which results are available in the literature.

  4. Seepage and Piping through Levees and Dikes using 2D and 3D Modeling Codes

    DTIC Science & Technology

    2016-06-01

    Modeling Codes Co as ta l a nd H yd ra ul ic s La bo ra to ry Hwai-Ping Cheng, Stephen M. England, and Clarissa M. Murray June 2016...Flood & Coastal Storm Damage Reduction Program ERDC/CHL TR-16-6 June 2016 Seepage and Piping through Levees and Dikes Using 2D and 3D Modeling Codes ...TYPE Final Report 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Seepage and Piping through Levees and Dikes using 2D and 3D Modeling Codes

  5. 3D video coding: an overview of present and upcoming standards

    NASA Astrophysics Data System (ADS)

    Merkle, Philipp; Müller, Karsten; Wiegand, Thomas

    2010-07-01

    An overview of existing and upcoming 3D video coding standards is given. Various different 3D video formats are available, each with individual pros and cons. The 3D video formats can be separated into two classes: video-only formats (such as stereo and multiview video) and depth-enhanced formats (such as video plus depth and multiview video plus depth). Since all these formats exist of at least two video sequences and possibly additional depth data, efficient compression is essential for the success of 3D video applications and technologies. For the video-only formats the H.264 family of coding standards already provides efficient and widely established compression algorithms: H.264/AVC simulcast, H.264/AVC stereo SEI message, and H.264/MVC. For the depth-enhanced formats standardized coding algorithms are currently being developed. New and specially adapted coding approaches are necessary, as the depth or disparity information included in these formats has significantly different characteristics than video and is not displayed directly, but used for rendering. Motivated by evolving market needs, MPEG has started an activity to develop a generic 3D video standard within the 3DVC ad-hoc group. Key features of the standard are efficient and flexible compression of depth-enhanced 3D video representations and decoupling of content creation and display requirements.

  6. Depth-based coding of MVD data for 3D video extension of H.264/AVC

    NASA Astrophysics Data System (ADS)

    Rusanovskyy, Dmytro; Hannuksela, Miska M.; Su, Wenyi

    2013-06-01

    This paper describes a novel approach of using depth information for advanced coding of associated video data in Multiview Video plus Depth (MVD)-based 3D video systems. As a possible implementation of this conception, we describe two coding tools that have been developed for H.264/AVC based 3D Video Codec as response to Moving Picture Experts Group (MPEG) Call for Proposals (CfP). These tools are Depth-based Motion Vector Prediction (DMVP) and Backward View Synthesis Prediction (BVSP). Simulation results conducted under JCT-3V/MPEG 3DV Common Test Conditions show, that proposed in this paper tools reduce bit rate of coded video data by 15% of average delta bit rate reduction, which results in 13% of bit rate savings on total for the MVD data over the state-of-the-art MVC+D coding. Moreover, presented in this paper conception of depth-based coding of video has been further developed by MPEG 3DV and JCT-3V and this work resulted in even higher compression efficiency, bringing about 20% of delta bit rate reduction on total for coded MVD data over the reference MVC+D coding. Considering significant gains, proposed in this paper coding approach can be beneficial for development of new 3D video coding standards. [Figure not available: see fulltext.

  7. Comparison of a 3-D GPU-Assisted Maxwell Code and Ray Tracing for Reflectometry on ITER

    NASA Astrophysics Data System (ADS)

    Gady, Sarah; Kubota, Shigeyuki; Johnson, Irena

    2015-11-01

    Electromagnetic wave propagation and scattering in magnetized plasmas are important diagnostics for high temperature plasmas. 1-D and 2-D full-wave codes are standard tools for measurements of the electron density profile and fluctuations; however, ray tracing results have shown that beam propagation in tokamak plasmas is inherently a 3-D problem. The GPU-Assisted Maxwell Code utilizes the FDTD (Finite-Difference Time-Domain) method for solving the Maxwell equations with the cold plasma approximation in a 3-D geometry. Parallel processing with GPGPU (General-Purpose computing on Graphics Processing Units) is used to accelerate the computation. Previously, we reported on initial comparisons of the code results to 1-D numerical and analytical solutions, where the size of the computational grid was limited by the on-board memory of the GPU. In the current study, this limitation is overcome by using domain decomposition and an additional GPU. As a practical application, this code is used to study the current design of the ITER Low Field Side Reflectometer (LSFR) for the Equatorial Port Plug 11 (EPP11). A detailed examination of Gaussian beam propagation in the ITER edge plasma will be presented, as well as comparisons with ray tracing. This work was made possible by funding from the Department of Energy for the Summer Undergraduate Laboratory Internship (SULI) program. This work is supported by the US DOE Contract No.DE-AC02-09CH11466 and DE-FG02-99-ER54527.

  8. Edge-based intramode selection for depth-map coding in 3D-HEVC.

    PubMed

    Park, Chun-Su

    2015-01-01

    The 3D video extension of High Efficiency Video Coding (3D-HEVC) is the state-of-the-art video coding standard for the compression of the multiview video plus depth format. In the 3D-HEVC design, new depth-modeling modes (DMMs) are utilized together with the existing intraprediction modes for depth intracoding. The DMMs can provide more accurate prediction signals and thereby achieve better compression efficiency. However, testing the DMMs in the intramode decision process causes a drastic increase in the computational complexity. In this paper, we propose a fast mode decision algorithm for depth intracoding. The proposed algorithm first performs a simple edge classification in the Hadamard transform domain. Then, based on the edge classification results, the proposed algorithm selectively omits unnecessary DMMs in the mode decision process. Experimental results demonstrate that the proposed algorithm speeds up the mode decision process by up to 37.65% with negligible loss of coding efficiency.

  9. Electromagnetic 2D/3D Particle-in-Cell simulations of the solar wind interaction with lunar crustal anomalies.

    NASA Astrophysics Data System (ADS)

    Deca, Jan; Lapenta, Giovanni; Lembège, Bertrand; Divin, Andrey; Markidis, Stefano; Amaya, Jorge

    2013-04-01

    We present the first 2D/3D fully kinetic Particle-in-Cell simulations of the solar wind interaction with lunar crustal magnetic anomalies. The simulations are performed using the implicit electromagnetic Particle-in-Cell code iPIC3D [Markidis, Lapenta & Rizwan-uddin, 2010]. Multiscale physics is resolved for all plasma components (heavy ions, protons and electrons) in the code, recently updated with a set of open boundary conditions designed for solar wind-body interactions. We use a dipole to model the crustal anomaly. The dipole center is located outside the computational domain and the boundary representing the lunar surface is modeled as a particle-absorbing plane. Photo-emission from the lunar surface is at this point not included, but will be in future work. We study the behaviour of the dipole model with variable surface magnetic field strength under changing solar wind conditions and confirm that lunar crustal magnetic fields may indeed be strong enough to stand off the solar wind and form a mini-magnetosphere, as suggested by MHD simulations [Harnett & Winglee, 2000, 2002, 2003] and spacecraft observations [Kurata et al., 2005; Halekas et al., 2008; Wieser et al., 2010]. 3D-PIC simulations reveal to be very helpful to analyze the diversion/braking of the particle flux and the characteristics of the resulting particles accumulation. The particle flux to the surface is significantly reduced at the magnetic anomaly, surrounded by a region of enhanced density due to the magnetic mirror effect. Finally we will present preliminary results on the interaction of the solar wind with weaker magnetic anomalies in which highly non-adiabatic interactions are expected.

  10. Effects of electromagnetic field frequencies on chondrocytes in 3D cell-printed composite constructs.

    PubMed

    Yi, Hee-Gyeong; Kang, Kyung Shin; Hong, Jung Min; Jang, Jinah; Park, Moon Nyeo; Jeong, Young Hun; Cho, Dong-Woo

    2016-07-01

    In cartilage tissue engineering, electromagnetic field (EMF) therapy has been reported to have a modest effect on promoting cartilage regeneration. However, these studies were conducted using different frequencies of EMF to stimulate chondrocytes. Thus, it is necessary to investigate the effect of EMF frequency on cartilage formation. In addition to the stimulation, a scaffold is required to satisfy the characteristics of cartilage such as its hydrated and dense extracellular matrix, and a mechanical resilience to applied loads. Therefore, we 3D-printed a composite construct composed of a polymeric framework and a chondrocyte-laden hydrogel. Here, we observed frequency-dependent positive and negative effects on chondrogenesis using a 3D cell-printed cartilage tissue. We found that a frequency of 45 Hz promoted gene expression and secretion of extracellular matrix molecules of chondrocytes. In contrast, a frequency of 7.5 Hz suppressed chondrogenic differentiation in vitro. Additionally, the EMF-treated composite constructs prior to implantation showed consistent results with those of in vitro, suggesting that in vitro pre-treatment with different EMF frequencies provides different capabilities for the enhancement of cartilage formation in vivo. This correlation between EMF frequency and 3D-printed chondrocytes suggests the necessity for optimization of EMF parameters when this physical stimulus is applied to engineered cartilage. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1797-1804, 2016.

  11. Multitasking the INS3D-LU code on the Cray Y-MP

    NASA Technical Reports Server (NTRS)

    Fatoohi, Rod; Yoon, Seokkwan

    1991-01-01

    This paper presents the results of multitasking the INS3D-LU code on eight processors. The code is a full Navier-Stokes solver for incompressible fluid in three dimensional generalized coordinates using a lower-upper symmetric-Gauss-Seidel implicit scheme. This code has been fully vectorized on oblique planes of sweep and parallelized using autotasking with some directives and minor modifications. The timing results for five grid sizes are presented and analyzed. The code has achieved a processing rate of over one Gflops.

  12. Impact of packet losses in scalable 3D holoscopic video coding

    NASA Astrophysics Data System (ADS)

    Conti, Caroline; Nunes, Paulo; Ducla Soares, Luís.

    2014-05-01

    Holoscopic imaging became a prospective glassless 3D technology to provide more natural 3D viewing experiences to the end user. Additionally, holoscopic systems also allow new post-production degrees of freedom, such as controlling the plane of focus or the viewing angle presented to the user. However, to successfully introduce this technology into the consumer market, a display scalable coding approach is essential to achieve backward compatibility with legacy 2D and 3D displays. Moreover, to effectively transmit 3D holoscopic content over error-prone networks, e.g., wireless networks or the Internet, error resilience techniques are required to mitigate the impact of data impairments in the user quality perception. Therefore, it is essential to deeply understand the impact of packet losses in terms of decoding video quality for the specific case of 3D holoscopic content, notably when a scalable approach is used. In this context, this paper studies the impact of packet losses when using a three-layer display scalable 3D holoscopic video coding architecture previously proposed, where each layer represents a different level of display scalability (i.e., L0 - 2D, L1 - stereo or multiview, and L2 - full 3D holoscopic). For this, a simple error concealment algorithm is used, which makes use of inter-layer redundancy between multiview and 3D holoscopic content and the inherent correlation of the 3D holoscopic content to estimate lost data. Furthermore, a study of the influence of 2D views generation parameters used in lower layers on the performance of the used error concealment algorithm is also presented.

  13. Transport analysis in toroidal helical plasmas using the integrated code: TASK3D

    NASA Astrophysics Data System (ADS)

    Wakasa, A.; Fukuyama, A.; Murakami, S.; Beidler, C. D.; Maassberg, H.; Yokoyama, M.; Sato, M.

    2009-11-01

    The integrated simulation code in helical plasmas, TASK3D, is being developed on the basis of an integrated modeling code for tokamak plasma, TASK. In helical systems, the neoclassical transport is one of the important issues in addition to the anomalous transport, because of strong temperature dependence of heat conductivity and an important role in determining the radial electric field. We have already constructed the neoclassical transport database in LHD, DGN/LHD. The mono-energetic diffusion coefficients are evaluated based on the Monte Carlo method by DCOM code and the mono-energetic diffusion coefficients database is constructed using a neural network technique. Also we apply GSRAKE code, which solves the ripple-averaged drift kinetic equation, to obtain transport coefficients in highly collisionless regime. We have newly incorporated the DGN/LHD module into TASK3D. We will present several results of transport simulation in typical LHD plasmas.

  14. A cut-&-paste strategy for the 3-D inversion of helicopter-borne electromagnetic data - II. Combining regional 1-D and local 3-D inversion

    NASA Astrophysics Data System (ADS)

    Ullmann, A.; Scheunert, M.; Afanasjew, M.; Börner, R.-U.; Siemon, B.; Spitzer, K.

    2016-07-01

    As a standard procedure, multi-frequency helicopter-borne electromagnetic (HEM) data are inverted to conductivity-depth models using 1-D inversion methods, which may, however, fail in areas of strong lateral conductivity contrasts (so-called induction anomalies). Such areas require more realistic multi-dimensional modelling. Since the full 3-D inversion of an entire HEM data set is still extremely time consuming, our idea is to combine fast 1-D and accurate but numerically expensive 3-D inversion of HEM data in such a way that the full 3-D inversion is only carried out for those parts of a HEM survey which are affected by induction anomalies. For all other parts, a 1-D inversion method is sufficient. We present a newly developed algorithm for identification, selection, and extraction of induction anomalies in HEM data sets and show how the 3-D inversion model of the anomalous area is re-integrated into the quasi-1-D background. Our proposed method is demonstrated to work properly on a synthetic and a field HEM data set from the Cuxhaven tunnel valley in Germany. We show that our 1-D/3-D approach yields better results compared to 1-D inversions in areas where 3-D effects occur.

  15. 3D Neutron Transport PWR Full-core Calculation with RMC code

    NASA Astrophysics Data System (ADS)

    Qiu, Yishu; She, Ding; Fan, Xiao; Wang, Kan; Li, Zeguang; Liang, Jingang; Leroyer, Hadrien

    2014-06-01

    Nowadays, there are more and more interests in the use of Monte Carlo codes to calculate the detailed power density distributions in full-core reactors. With the Inspur TS1000 HPC Server of Tsinghua University, several calculations have been done based on the EDF 3D Neutron Transport PWR Full-core benchmark through large-scale parallelism. To investigate and compare the results of the deterministic method and Monte Carlo method, EDF R&D and Department of Engineering Physics of Tsinghua University are having a collaboration to make code to code verification. So in this paper, two codes are used. One is the code COCAGNE developed by the EDF R&D, a deterministic core code, and the other is the Monte Carlo code RMC developed by Department of Engineering Physics in Tsinghua University. First, the full-core model is described and a 26-group calculation was performed by these two codes using the same 26-group cross-section library provided by EDF R&D. Then the parallel and tally performance of RMC is discussed. RMC employs a novel algorithm which can cut down most of the communications. It can be seen clearly that the speedup ratio almost linearly increases with the nodes. Furthermore the cell-mapping method applied by RMC consumes little time to tally even millions of cells. The results of the codes COCAGNE and RMC are compared in three ways. The results of these two codes agree well with each other. It can be concluded that both COCAGNE and RMC are able to provide 3D-transport solutions associated with detailed power density distributions calculation in PWR full-core reactors. Finally, to investigate how many histories are needed to obtain a given standard deviation for a full 3D solution, the non-symmetrized condensed 2-group fluxes of RMC are discussed.

  16. Turbomachinery Heat Transfer and Loss Modeling for 3D Navier-Stokes Codes

    NASA Technical Reports Server (NTRS)

    DeWitt, Kenneth; Ameri, Ali

    2005-01-01

    This report's contents focus on making use of NASA Glenn on-site computational facilities,to develop, validate, and apply models for use in advanced 3D Navier-Stokes Computational Fluid Dynamics (CFD) codes to enhance the capability to compute heat transfer and losses in turbomachiney.

  17. Users manual for the NASA Lewis three-dimensional ice accretion code (LEWICE 3D)

    NASA Technical Reports Server (NTRS)

    Bidwell, Colin S.; Potapczuk, Mark G.

    1993-01-01

    A description of the methodology, the algorithms, and the input and output data along with an example case for the NASA Lewis 3D ice accretion code (LEWICE3D) has been produced. The manual has been designed to help the user understand the capabilities, the methodologies, and the use of the code. The LEWICE3D code is a conglomeration of several codes for the purpose of calculating ice shapes on three-dimensional external surfaces. A three-dimensional external flow panel code is incorporated which has the capability of calculating flow about arbitrary 3D lifting and nonlifting bodies with external flow. A fourth order Runge-Kutta integration scheme is used to calculate arbitrary streamlines. An Adams type predictor-corrector trajectory integration scheme has been included to calculate arbitrary trajectories. Schemes for calculating tangent trajectories, collection efficiencies, and concentration factors for arbitrary regions of interest for single droplets or droplet distributions have been incorporated. A LEWICE 2D based heat transfer algorithm can be used to calculate ice accretions along surface streamlines. A geometry modification scheme is incorporated which calculates the new geometry based on the ice accretions generated at each section of interest. The three-dimensional ice accretion calculation is based on the LEWICE 2D calculation. Both codes calculate the flow, pressure distribution, and collection efficiency distribution along surface streamlines. For both codes the heat transfer calculation is divided into two regions, one above the stagnation point and one below the stagnation point, and solved for each region assuming a flat plate with pressure distribution. Water is assumed to follow the surface streamlines, hence starting at the stagnation zone any water that is not frozen out at a control volume is assumed to run back into the next control volume. After the amount of frozen water at each control volume has been calculated the geometry is modified by

  18. Implementation of a kappa-epsilon turbulence model to RPLUS3D code

    NASA Technical Reports Server (NTRS)

    Chitsomboon, Tawit

    1992-01-01

    The RPLUS3D code has been developed at the NASA Lewis Research Center to support the National Aerospace Plane (NASP) project. The code has the ability to solve three dimensional flowfields with finite rate combustion of hydrogen and air. The combustion process of the hydrogen-air system are simulated by an 18 reaction path, 8 species chemical kinetic mechanism. The code uses a Lower-Upper (LU) decomposition numerical algorithm as its basis, making it a very efficient and robust code. Except for the Jacobian matrix for the implicit chemistry source terms, there is no inversion of a matrix even though a fully implicit numerical algorithm is used. A k-epsilon turbulence model has recently been incorporated into the code. Initial validations have been conducted for a flow over a flat plate. Results of the validation studies are shown. Some difficulties in implementing the k-epsilon equations to the code are also discussed.

  19. GPU-advanced 3D electromagnetic simulations of superconductors in the Ginzburg–Landau formalism

    SciTech Connect

    Stošić, Darko; Stošić, Dušan; Ludermir, Teresa

    2016-10-01

    Ginzburg–Landau theory is one of the most powerful phenomenological theories in physics, with particular predictive value in superconductivity. The formalism solves coupled nonlinear differential equations for both the electronic and magnetic responsiveness of a given superconductor to external electromagnetic excitations. With order parameter varying on the short scale of the coherence length, and the magnetic field being long-range, the numerical handling of 3D simulations becomes extremely challenging and time-consuming for realistic samples. Here we show precisely how one can employ graphics-processing units (GPUs) for this type of calculations, and obtain physics answers of interest in a reasonable time-frame – with speedup of over 100× compared to best available CPU implementations of the theory on a 256{sup 3} grid.

  20. Research on 3D marine electromagnetic interferometry with synthetic sources for suppressing the airwave interference

    NASA Astrophysics Data System (ADS)

    Zhang, Jian-Guo; Wu, Xin; Qi, You-Zheng; Huang, Ling; Fang, Guang-You

    2013-12-01

    In order to suppress the airwave noise in marine controlled-source electromagnetic (CSEM) data, we propose a 3D deconvolution (3DD) interferometry method with a synthetic aperture source and obtain the relative anomaly coefficient (RAC) of the EM field reflection responses to show the degree for suppressing the airwave. We analyze the potential of the proposed method for suppressing the airwave, and compare the proposed method with traditional methods in their effectiveness. A method to select synthetic source length is derived and the effect of the water depth on RAC is examined via numerical simulations. The results suggest that 3DD interferometry method with a synthetic source can effectively suppress the airwave and enhance the potential of marine CSEM to hydrocarbon exploration.

  1. GPU-advanced 3D electromagnetic simulations of superconductors in the Ginzburg-Landau formalism

    NASA Astrophysics Data System (ADS)

    Stošić, Darko; Stošić, Dušan; Ludermir, Teresa; Stošić, Borko; Milošević, Milorad V.

    2016-10-01

    Ginzburg-Landau theory is one of the most powerful phenomenological theories in physics, with particular predictive value in superconductivity. The formalism solves coupled nonlinear differential equations for both the electronic and magnetic responsiveness of a given superconductor to external electromagnetic excitations. With order parameter varying on the short scale of the coherence length, and the magnetic field being long-range, the numerical handling of 3D simulations becomes extremely challenging and time-consuming for realistic samples. Here we show precisely how one can employ graphics-processing units (GPUs) for this type of calculations, and obtain physics answers of interest in a reasonable time-frame - with speedup of over 100× compared to best available CPU implementations of the theory on a 2563 grid.

  2. [A 3D FEM model for calculation of electromagnetic fields in transmagnetic stimulation].

    PubMed

    Seilwinder, J; Kammer, T; Andrä, W; Bellemann, M E

    2002-01-01

    We developed a realistic finite elements method (FEM) model of the brain for the calculation of electromagnetic fields in transcranial magnetic stimulation (TMS). A focal butterfly stimulation coil was X-rayed, parameterized, and modeled. The magnetic field components of the TMS coil were calculated and compared for validation to pointwise measurements of the magnetic fields with a Hall sensor. We found a mean deviation of 7.4% at an axial distance of 20 mm to the coil. A 3D brain model with the biological tissues of white and gray matter, bone, and cerebrospinal fluid was developed. At a current sweep of 1000 A in 120 microseconds, the maximum induced current density in gray matter was 177 mA/m2 and the strongest electric field gradient covered an area of 40 mm x 53 mm.

  3. Proceeding On : Parallelisation Of Critical Code Passages In PHOENIX/3D

    NASA Astrophysics Data System (ADS)

    Arkenberg, Mario; Wichert, Viktoria; Hauschildt, Peter H.

    2016-10-01

    Highly resolved state-of-the-art 3D atmosphere simulations will remain computationally extremely expensive for years to come. In addition to the need for more computing power, rethinking coding practices is necessary. We take a dual approach here, by introducing especially adapted, parallel numerical methods and correspondingly parallelising time critical code passages. In the following, we present our work on PHOENIX/3D.While parallelisation is generally worthwhile, it requires revision of time-consuming subroutines with respect to separability of localised data and variables in order to determine the optimal approach. Of course, the same applies to the code structure. The importance of this ongoing work can be showcased by recently derived benchmark results, which were generated utilis- ing MPI and OpenMP. Furthermore, the need for a careful and thorough choice of an adequate, machine dependent setup is discussed.

  4. RELAP5-3D Code Includes Athena Features and Models

    SciTech Connect

    Richard A. Riemke; Cliff B. Davis; Richard R. Schultz

    2006-07-01

    Version 2.3 of the RELAP5-3D computer program includes all features and models previously available only in the ATHENA version of the code. These include the addition of new working fluids (i.e., ammonia, blood, carbon dioxide, glycerol, helium, hydrogen, lead-bismuth, lithium, lithium-lead, nitrogen, potassium, sodium, and sodium-potassium) and a magnetohydrodynamic model that expands the capability of the code to model many more thermal-hydraulic systems. In addition to the new working fluids along with the standard working fluid water, one or more noncondensable gases (e.g., air, argon, carbon dioxide, carbon monoxide, helium, hydrogen, krypton, nitrogen, oxygen, sf6, xenon) can be specified as part of the vapor/gas phase of the working fluid. These noncondensable gases were in previous versions of RELAP5- 3D. Recently four molten salts have been added as working fluids to RELAP5-3D Version 2.4, which has had limited release. These molten salts will be in RELAP5-3D Version 2.5, which will have a general release like RELAP5-3D Version 2.3. Applications that use these new features and models are discussed in this paper.

  5. Electromagnetic induction sounding and 3D laser imaging in support of a Mars methane analogue mission

    NASA Astrophysics Data System (ADS)

    Boivin, A.; Lai, P.; Samson, C.; Cloutis, E.; Holladay, S.; Monteiro Santos, F. A.

    2013-07-01

    The Mars Methane Analogue Mission simulates a micro-rover mission whose purpose is to detect, analyze, and determine the source of methane emissions on the planet's surface. As part of this project, both an electromagnetic induction sounder (EMIS) and a high-resolution triangulation-based 3D laser scanner were tested at the Jeffrey open-pit asbestos mine to identify and characterize geological environments favourable to the occurrence of methane. The presence of serpentinite in the form of chrysotile (asbestos), magnesium carbonate, and iron oxyhydroxides make the mine a likely location for methane production. The EMIS clearly delineated the contacts between the two geological units found at the mine, peridotite and slate, which are separated by a shear zone. Both the peridotite and slate units have low and uniform apparent electrical conductivity and magnetic susceptibility, while the shear zone has much higher conductivity and susceptibility, with greater variability. The EMIS data were inverted and the resulting model captured lateral conductivity variations through the different bedrock geological units buried beneath a gravel road. The 3D point cloud data acquired by the laser scanner were fitted with triangular meshes where steeply dipping triangles were plotted in dark grey to accentuate discontinuities. The resulting images were further processed using Sobel edge detection to highlight networks of fractures which are potential pathways for methane seepage.

  6. Development of Unsteady Aerodynamic and Aeroelastic Reduced-Order Models Using the FUN3D Code

    NASA Technical Reports Server (NTRS)

    Silva, Walter A.; Vatsa, Veer N.; Biedron, Robert T.

    2009-01-01

    Recent significant improvements to the development of CFD-based unsteady aerodynamic reduced-order models (ROMs) are implemented into the FUN3D unstructured flow solver. These improvements include the simultaneous excitation of the structural modes of the CFD-based unsteady aerodynamic system via a single CFD solution, minimization of the error between the full CFD and the ROM unsteady aero- dynamic solution, and computation of a root locus plot of the aeroelastic ROM. Results are presented for a viscous version of the two-dimensional Benchmark Active Controls Technology (BACT) model and an inviscid version of the AGARD 445.6 aeroelastic wing using the FUN3D code.

  7. Status report on the 'Merging' of the Electron-Cloud Code POSINST with the 3-D Accelerator PIC CODE WARP

    SciTech Connect

    Vay, J.-L.; Furman, M.A.; Azevedo, A.W.; Cohen, R.H.; Friedman, A.; Grote, D.P.; Stoltz, P.H.

    2004-04-19

    We have integrated the electron-cloud code POSINST [1] with WARP [2]--a 3-D parallel Particle-In-Cell accelerator code developed for Heavy Ion Inertial Fusion--so that the two can interoperate. Both codes are run in the same process, communicate through a Python interpreter (already used in WARP), and share certain key arrays (so far, particle positions and velocities). Currently, POSINST provides primary and secondary sources of electrons, beam bunch kicks, a particle mover, and diagnostics. WARP provides the field solvers and diagnostics. Secondary emission routines are provided by the Tech-X package CMEE.

  8. Turbine Internal and Film Cooling Modeling For 3D Navier-Stokes Codes

    NASA Technical Reports Server (NTRS)

    DeWitt, Kenneth; Garg Vijay; Ameri, Ali

    2005-01-01

    The aim of this research project is to make use of NASA Glenn on-site computational facilities in order to develop, validate and apply aerodynamic, heat transfer, and turbine cooling models for use in advanced 3D Navier-Stokes Computational Fluid Dynamics (CFD) codes such as the Glenn-" code. Specific areas of effort include: Application of the Glenn-HT code to specific configurations made available under Turbine Based Combined Cycle (TBCC), and Ultra Efficient Engine Technology (UEET) projects. Validating the use of a multi-block code for the time accurate computation of the detailed flow and heat transfer of cooled turbine airfoils. The goal of the current research is to improve the predictive ability of the Glenn-HT code. This will enable one to design more efficient turbine components for both aviation and power generation. The models will be tested against specific configurations provided by NASA Glenn.

  9. Object-adaptive depth compensated inter prediction for depth video coding in 3D video system

    NASA Astrophysics Data System (ADS)

    Kang, Min-Koo; Lee, Jaejoon; Lim, Ilsoon; Ho, Yo-Sung

    2011-01-01

    Nowadays, the 3D video system using the MVD (multi-view video plus depth) data format is being actively studied. The system has many advantages with respect to virtual view synthesis such as an auto-stereoscopic functionality, but compression of huge input data remains a problem. Therefore, efficient 3D data compression is extremely important in the system, and problems of low temporal consistency and viewpoint correlation should be resolved for efficient depth video coding. In this paper, we propose an object-adaptive depth compensated inter prediction method to resolve the problems where object-adaptive mean-depth difference between a current block, to be coded, and a reference block are compensated during inter prediction. In addition, unique properties of depth video are exploited to reduce side information required for signaling decoder to conduct the same process. To evaluate the coding performance, we have implemented the proposed method into MVC (multiview video coding) reference software, JMVC 8.2. Experimental results have demonstrated that our proposed method is especially efficient for depth videos estimated by DERS (depth estimation reference software) discussed in the MPEG 3DV coding group. The coding gain was up to 11.69% bit-saving, and it was even increased when we evaluated it on synthesized views of virtual viewpoints.

  10. Assessing the performance of a parallel MATLAB-based 3D convection code

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, G. J.; Hasenclever, J.; Phipps Morgan, J.; Shi, C.

    2008-12-01

    We are currently building 2D and 3D MATLAB-based parallel finite element codes for mantle convection and melting. The codes use the MATLAB implementation of core MPI commands (eg. Send, Receive, Broadcast) for message passing between computational subdomains. We have found that code development and algorithm testing are much faster in MATLAB than in our previous work coding in C or FORTRAN, this code was built from scratch with only 12 man-months of effort. The one extra cost w.r.t. C coding on a Beowulf cluster is the cost of the parallel MATLAB license for a >4core cluster. Here we present some preliminary results on the efficiency of MPI messaging in MATLAB on a small 4 machine, 16core, 32Gb RAM Intel Q6600 processor-based cluster. Our code implements fully parallelized preconditioned conjugate gradients with a multigrid preconditioner. Our parallel viscous flow solver is currently 20% slower for a 1,000,000 DOF problem on a single core in 2D as the direct solve MILAMIN MATLAB viscous flow solver. We have tested both continuous and discontinuous pressure formulations. We test with various configurations of network hardware, CPU speeds, and memory using our own and MATLAB's built in cluster profiler. So far we have only explored relatively small (up to 1.6GB RAM) test problems. We find that with our current code and Intel memory controller bandwidth limitations we can only get ~2.3 times performance out of 4 cores than 1 core per machine. Even for these small problems the code runs faster with message passing between 4 machines with one core each than 1 machine with 4 cores and internal messaging (1.29x slower), or 1 core (2.15x slower). It surprised us that for 2D ~1GB-sized problems with only 3 multigrid levels, the direct- solve on the coarsest mesh consumes comparable time to the iterative solve on the finest mesh - a penalty that is greatly reduced either by using a 4th multigrid level or by using an iterative solve at the coarsest grid level. We plan to

  11. 3-D inversion of airborne electromagnetic data parallelized and accelerated by local mesh and adaptive soundings

    NASA Astrophysics Data System (ADS)

    Yang, Dikun; Oldenburg, Douglas W.; Haber, Eldad

    2014-03-01

    Airborne electromagnetic (AEM) methods are highly efficient tools for assessing the Earth's conductivity structures in a large area at low cost. However, the configuration of AEM measurements, which typically have widely distributed transmitter-receiver pairs, makes the rigorous modelling and interpretation extremely time-consuming in 3-D. Excessive overcomputing can occur when working on a large mesh covering the entire survey area and inverting all soundings in the data set. We propose two improvements. The first is to use a locally optimized mesh for each AEM sounding for the forward modelling and calculation of sensitivity. This dedicated local mesh is small with fine cells near the sounding location and coarse cells far away in accordance with EM diffusion and the geometric decay of the signals. Once the forward problem is solved on the local meshes, the sensitivity for the inversion on the global mesh is available through quick interpolation. Using local meshes for AEM forward modelling avoids unnecessary computing on fine cells on a global mesh that are far away from the sounding location. Since local meshes are highly independent, the forward modelling can be efficiently parallelized over an array of processors. The second improvement is random and dynamic down-sampling of the soundings. Each inversion iteration only uses a random subset of the soundings, and the subset is reselected for every iteration. The number of soundings in the random subset, determined by an adaptive algorithm, is tied to the degree of model regularization. This minimizes the overcomputing caused by working with redundant soundings. Our methods are compared against conventional methods and tested with a synthetic example. We also invert a field data set that was previously considered to be too large to be practically inverted in 3-D. These examples show that our methodology can dramatically reduce the processing time of 3-D inversion to a practical level without losing resolution

  12. Equation-of-State Test Suite for the DYNA3D Code

    SciTech Connect

    Benjamin, Russell D.

    2015-11-05

    This document describes the creation and implementation of a test suite for the Equationof- State models in the DYNA3D code. A customized input deck has been created for each model, as well as a script that extracts the relevant data from the high-speed edit file created by DYNA3D. Each equation-of-state model is broken apart and individual elements of the model are tested, as well as testing the entire model. The input deck for each model is described and the results of the tests are discussed. The intent of this work is to add this test suite to the validation suite presently used for DYNA3D.

  13. Peach Bottom 2 Turbine Trip Simulation Using TRAC-BF1/COS3D, a Best-Estimate Coupled 3-D Core and Thermal-Hydraulic Code System

    SciTech Connect

    Ui, Atsushi; Miyaji, Takamasa

    2004-10-15

    The best-estimate coupled three-dimensional (3-D) core and thermal-hydraulic code system TRAC-BF1/COS3D has been developed. COS3D, based on a modified one-group neutronic model, is a 3-D core simulator used for licensing analyses and core management of commercial boiling water reactor (BWR) plants in Japan. TRAC-BF1 is a plant simulator based on a two-fluid model. TRAC-BF1/COS3D is a coupled system of both codes, which are connected using a parallel computing tool. This code system was applied to the OECD/NRC BWR Turbine Trip Benchmark. Since the two-group cross-section tables are provided by the benchmark team, COS3D was modified to apply to this specification. Three best-estimate scenarios and four hypothetical scenarios were calculated using this code system. In the best-estimate scenario, the predicted core power with TRAC-BF1/COS3D is slightly underestimated compared with the measured data. The reason seems to be a slight difference in the core boundary conditions, that is, pressure changes and the core inlet flow distribution, because the peak in this analysis is sensitive to them. However, the results of this benchmark analysis show that TRAC-BF1/COS3D gives good precision for the prediction of the actual BWR transient behavior on the whole. Furthermore, the results with the modified one-group model and the two-group model were compared to verify the application of the modified one-group model to this benchmark. This comparison shows that the results of the modified one-group model are appropriate and sufficiently precise.

  14. FOI-PERFECT code: 3D relaxation MHD modeling and Applications

    NASA Astrophysics Data System (ADS)

    Wang, Gang-Hua; Duan, Shu-Chao; Comutational Physics Team Team

    2016-10-01

    One of the challenges in numerical simulations of electromagnetically driven high energy density (HED) systems is the existence of vacuum region. FOI-PERFECT code adopts a full relaxation magnetohydrodynamic (MHD) model. The electromagnetic part of the conventional model adopts the magnetic diffusion approximation. The vacuum region is approximated by artificially increasing the resistivity. On one hand the phase/group velocity is superluminal and hence non-physical in the vacuum region, on the other hand a diffusion equation with large diffusion coefficient can only be solved by implicit scheme which is difficult to be parallelized and converge. A better alternative is to solve the full electromagnetic equations. Maxwell's equations coupled with the constitutive equation, generalized Ohm's law, constitute a relaxation model. The dispersion relation is given to show its transition from electromagnetic propagation in vacuum to resistive MHD in plasma in a natural way. The phase and group velocities are finite for this system. A better time stepping is adopted to give a 3rd full order convergence in time domain without the stiff relaxation term restriction. Therefore it is convenient for explicit & parallel computations. Some numerical results of FOI-PERFECT code are also given. Project supported by the National Natural Science Foundation of China (Grant No. 11571293) And Foundation of China Academy of Engineering Physics (Grant No. 2015B0201023).

  15. Induced Polarization with Electromagnetic Coupling: 3D Spectral Imaging Theory EMSP Project No. 73836

    SciTech Connect

    Morgan, F. Dale

    2003-06-01

    considered invertible by our existing 2D/3D complex resistivity codes. The results of this exercise were inconclusive because the ground-truthing phase of the operation failed to detect ny concentration of NAPL above a requisite threshold of 40-50{micro}g/g. It is our understanding that this threshold level is based upon analytic chemical partition analysis, which is dependent upon the physicochemical properties of the soil, its pore-fluid, and organic constituents [Cohen and Mercer, 1993], and thus represents a necessary and sufficient condition to confirm the presence of NAPL. Therefore, since the round-truthing phase never found PCE concentrations in excess of {approx}3mg/g, there is no irrefutable evidence of NAPL; hence, the objective of the FY01 exercise could not be completed. Nonetheless, ERL's conversion results agree well with the ground truth considering the sparseness of the CRS boreholes, low concentrations of ''PCE'' (< 3{micro}g/g), and despite poor electrodes. Note that the displacement of the enter of the SIP phase anomaly from that of the ground truth data might be due to inaccuracies in the SIP conversion (which we are still working on improving) or sampling depth errors during the ground-truthing phase which could cumulatively amount to a meter or more. (3) As a continuation of the FY01 efforts, another et of surface and borehole SIP measurements were planned at another SRS site during FY02, which unlike he FY01 site,had been verified to have substantial DNAPL presence by SRS engineers. The plan to use phoenix Geophysics SIP equipment could not materialize because Phoenix discontinued its SIP line and planned to introduce a new line in the Spring/Summer of 2003, which will be too late for us. So our planned second fieldwork of FY02 defaults again to Zonge Engineering and Research Organization equipment. (4) developments on the modeling and inversion of the new complex resistivity code, that will incorporate conductive coupling, stalled to give way to the

  16. IM3D: A parallel Monte Carlo code for efficient simulations of primary radiation displacements and damage in 3D geometry

    PubMed Central

    Li, Yong Gang; Yang, Yang; Short, Michael P.; Ding, Ze Jun; Zeng, Zhi; Li, Ju

    2015-01-01

    SRIM-like codes have limitations in describing general 3D geometries, for modeling radiation displacements and damage in nanostructured materials. A universal, computationally efficient and massively parallel 3D Monte Carlo code, IM3D, has been developed with excellent parallel scaling performance. IM3D is based on fast indexing of scattering integrals and the SRIM stopping power database, and allows the user a choice of Constructive Solid Geometry (CSG) or Finite Element Triangle Mesh (FETM) method for constructing 3D shapes and microstructures. For 2D films and multilayers, IM3D perfectly reproduces SRIM results, and can be ∼102 times faster in serial execution and > 104 times faster using parallel computation. For 3D problems, it provides a fast approach for analyzing the spatial distributions of primary displacements and defect generation under ion irradiation. Herein we also provide a detailed discussion of our open-source collision cascade physics engine, revealing the true meaning and limitations of the “Quick Kinchin-Pease” and “Full Cascades” options. The issues of femtosecond to picosecond timescales in defining displacement versus damage, the limitation of the displacements per atom (DPA) unit in quantifying radiation damage (such as inadequacy in quantifying degree of chemical mixing), are discussed. PMID:26658477

  17. A hybrid kinetic hot ion PIC module for the M3D-C1 Code

    NASA Astrophysics Data System (ADS)

    Breslau, J. A.; Ferraro, N.; Jardin, S. C.; Kalyanaraman, K.

    2016-10-01

    Building on the success of the original M3D code with the addition of efficient high-order, high-continuity finite elements and a fully implicit time advance making use of cutting-edge numerical techniques, M3D-C1 has become a flagship code for realistic time-dependent 3D MHD and two-fluid calculations of the nonlinear evolution of macroinstabilities in tokamak plasmas. It is therefore highly desirable to introduce to M3D-C1 one of the most-used features of its predecessor: the option to use a drift-kinetic delta- f PIC model for a minority population of energetic ions (representing, e.g., beam ions or fusion alpha particles) coupled with the usual finite element advance of the bulk ion and electron fluids through its pressure tensor. We describe the implementation of a module for this purpose using high-order-of-accuracy numerical integration and carefully tuned to take advantage of state-of-the-art multicore processing elements. Verification results for a toroidal Alfvén eigenmode test problem will be presented, along with a demonstration of favorable parallel scaling to large numbers of supercomputer nodes.

  18. Progress on accelerated calculation of 3D MHD equilibrium with the PIES code

    NASA Astrophysics Data System (ADS)

    Raburn, Daniel; Reiman, Allan; Monticello, Donald

    2016-10-01

    Continuing progress has been made in accelerating the 3D MHD equilibrium code, PIES, using an external numerical wrapper. The PIES code (Princeton Iterative Equilibrium Solver) is capable of calculating 3D MHD equilibria with islands. The numerical wrapper has been demonstrated to greatly improve the rate of convergence in numerous cases corresponding to equilibria in the TFTR device where magnetic islands are present; the numerical wrapper makes use of a Jacobian-free Newton-Krylov solver along with adaptive preconditioning and a sophisticated subspace-restricted Levenberg backtracking algorithm. The wrapper has recently been improved by automation which combines the preexisting backtracking algorithm with insights gained from the stability of the Picard algorithm traditionally used with PIES. Improved progress logging and stopping criteria have also been incorporated in to the numerical wrapper.

  19. Voxel-coding method for quantification of vascular structure from 3D images

    NASA Astrophysics Data System (ADS)

    Soltanian-Zadeh, Hamid; Shahrokni, Ali; Zoroofi, Reza A.

    2001-05-01

    This paper presents an image processing method for information extraction from 3D images of vasculature. It automates the study of vascular structures by extracting quantitative information such as skeleton, length, diameter, and vessel-to- tissue ratio for different vessels as well as their branches. Furthermore, it generates 3D visualization of vessels based on desired anatomical characteristics such as vessel diameter or 3D connectivity. Steps of the proposed approach are as follows. (1) Preprocessing, in which intensity adjustment, optimal thresholding, and median filtering are done. (2) 3D thinning, in which medial axis and skeleton of the vessels are found. (3) Branch labeling, in which different branches are identified and each voxel is assigned to the corresponding branch. (4) Quantitation, in which length of each branch is estimated, based on the number of voxels assigned to it, and its diameter is calculated using the medial axis direction. (5) Visualization, in which vascular structure is shown in 3D, using color coding and surface rendering methods. We have tested and evaluated the proposed algorithms using simulated images of multi-branch vessels and real confocal microscopic images of the vessels in rat brains. Experimental results illustrate performance of the methods and usefulness of the results for medical image analysis applications.

  20. A tetrahedral mesh generation approach for 3D marine controlled-source electromagnetic modeling

    NASA Astrophysics Data System (ADS)

    Um, Evan Schankee; Kim, Seung-Sep; Fu, Haohuan

    2017-03-01

    3D finite-element (FE) mesh generation is a major hurdle for marine controlled-source electromagnetic (CSEM) modeling. In this paper, we present a FE discretization operator (FEDO) that automatically converts a 3D finite-difference (FD) model into reliable and efficient tetrahedral FE meshes for CSEM modeling. FEDO sets up wireframes of a background seabed model that precisely honors the seafloor topography. The wireframes are then partitioned into multiple regions. Outer regions of the wireframes are discretized with coarse tetrahedral elements whose maximum size is as large as a skin depth of the regions. We demonstrate that such coarse meshes can produce accurate FE solutions because numerical dispersion errors of tetrahedral meshes do not accumulate but oscillates. In contrast, central regions of the wireframes are discretized with fine tetrahedral elements to describe complex geology in detail. The conductivity distribution is mapped from FD to FE meshes in a volume-averaged sense. To avoid excessive mesh refinement around receivers, we introduce an effective receiver size. Major advantages of FEDO are summarized as follow. First, FEDO automatically generates reliable and economic tetrahedral FE meshes without adaptive meshing or interactive CAD workflows. Second, FEDO produces FE meshes that precisely honor the boundaries of the seafloor topography. Third, FEDO derives multiple sets of FE meshes from a given FD model. Each FE mesh is optimized for a different set of sources and receivers and is fed to a subgroup of processors on a parallel computer. This divide and conquer approach improves the parallel scalability of the FE solution. Both accuracy and effectiveness of FEDO are demonstrated with various CSEM examples.

  1. Advanced 3D electromagnetic and particle-in-cell modeling on structured/unstructured hybrid grids

    SciTech Connect

    Seidel, D.B.; Pasik, M.F.; Kiefer, M.L.; Riley, D.J.; Turner, C.D.

    1998-01-01

    New techniques have been recently developed that allow unstructured, free meshes to be embedded into standard 3-dimensional, rectilinear, finite-difference time-domain grids. The resulting hybrid-grid modeling capability allows the higher resolution and fidelity of modeling afforded by free meshes to be combined with the simplicity and efficiency of rectilinear techniques. Integration of these new methods into the full-featured, general-purpose QUICKSILVER electromagnetic, Particle-In-Cell (PIC) code provides new modeling capability for a wide variety of electromagnetic and plasma physics problems. To completely exploit the integration of this technology into QUICKSILVER for applications requiring the self-consistent treatment of charged particles, this project has extended existing PIC methods for operation on these hybrid unstructured/rectilinear meshes. Several technical issues had to be addressed in order to accomplish this goal, including the location of particles on the unstructured mesh, adequate conservation of charge, and the proper handling of particles in the transition region between structured and unstructured portions of the hybrid grid.

  2. A non-linear 3D printed electromagnetic vibration energy harvester

    NASA Astrophysics Data System (ADS)

    Constantinou, P.; Roy, S.

    2015-12-01

    This paper describes a novel electromagnetic energy harvester that exploits the low flexural modulus of ABS and comprises of a nonlinear mechanism to enhance the generated power and bandwidth. The device is printed using desktop additive manufacturing techniques (3D printing) that use thermoplastics. It has a ‘V’ spring topology and exhibits a softening spring non-linearity introduced through the magnetic arrangement, which introduces a monostable potential well. A model is presented and measurements correspond favourably. The produced prototype generates a peak power of approximately 2.5mW at a frame acceleration of 1g and has a power bandwidth of approximately 1.2→1.5Hz and 3.5→3.9Hz during up and down sweeps respectively. The device has a power density of 0.4mW/cm3 at a frame acceleration of 1g and a density of 0.04mW/cm3 from a generated power of 25μW at 0.1g.

  3. Algebraic multigrid preconditioning within parallel finite-element solvers for 3-D electromagnetic modelling problems in geophysics

    NASA Astrophysics Data System (ADS)

    Koldan, Jelena; Puzyrev, Vladimir; de la Puente, Josep; Houzeaux, Guillaume; Cela, José María

    2014-06-01

    We present an elaborate preconditioning scheme for Krylov subspace methods which has been developed to improve the performance and reduce the execution time of parallel node-based finite-element (FE) solvers for 3-D electromagnetic (EM) numerical modelling in exploration geophysics. This new preconditioner is based on algebraic multigrid (AMG) that uses different basic relaxation methods, such as Jacobi, symmetric successive over-relaxation (SSOR) and Gauss-Seidel, as smoothers and the wave front algorithm to create groups, which are used for a coarse-level generation. We have implemented and tested this new preconditioner within our parallel nodal FE solver for 3-D forward problems in EM induction geophysics. We have performed series of experiments for several models with different conductivity structures and characteristics to test the performance of our AMG preconditioning technique when combined with biconjugate gradient stabilized method. The results have shown that, the more challenging the problem is in terms of conductivity contrasts, ratio between the sizes of grid elements and/or frequency, the more benefit is obtained by using this preconditioner. Compared to other preconditioning schemes, such as diagonal, SSOR and truncated approximate inverse, the AMG preconditioner greatly improves the convergence of the iterative solver for all tested models. Also, when it comes to cases in which other preconditioners succeed to converge to a desired precision, AMG is able to considerably reduce the total execution time of the forward-problem code-up to an order of magnitude. Furthermore, the tests have confirmed that our AMG scheme ensures grid-independent rate of convergence, as well as improvement in convergence regardless of how big local mesh refinements are. In addition, AMG is designed to be a black-box preconditioner, which makes it easy to use and combine with different iterative methods. Finally, it has proved to be very practical and efficient in the

  4. User Guide for the R5EXEC Coupling Interface in the RELAP5-3D Code

    SciTech Connect

    Forsmann, J. Hope; Weaver, Walter L.

    2015-04-01

    This report describes the R5EXEC coupling interface in the RELAP5-3D computer code from the users perspective. The information in the report is intended for users who want to couple RELAP5-3D to other thermal-hydraulic, neutron kinetics, or control system simulation codes.

  5. The Transient 3-D Transport Coupled Code TORT-TD/ATTICA3D for High-Fidelity Pebble-Bed HTGR Analyses

    NASA Astrophysics Data System (ADS)

    Seubert, Armin; Sureda, Antonio; Lapins, Janis; Bader, Johannes; Laurien, Eckart

    2012-01-01

    This article describes the 3D discrete ordinates-based coupled code system TORT-TD/ATTICA3D that aims at steady state and transient analyses of pebble-bed high-temperature gas cooled reactors. In view of increasing computing power, the application of time-dependent neutron transport methods becomes feasible for best estimate evaluations of safety margins. The calculation capabilities of TORT-TD/ATTICA3D are presented along with the coupling approach, with focus on the time-dependent neutron transport features of TORT-TD. Results obtained for the OECD/NEA/NSC PBMR-400 benchmark demonstrate the transient capabilities of TORT-TD/ATTICA3D.

  6. Methods used in WARP3d, a three-dimensional PIC/accelerator code

    SciTech Connect

    Grote, D.P.; Friedman, A.; Haber, I.

    1997-02-28

    WARP-3d(1,2), a three-dimensional PIC/accelerator code, has been developed over several years and has played a major role in the design and analysis of space-charge dominated beam experiments being carried out by the heavy-ion fusion programs at LLNL and LBNL. Major features of the code will be reviewed, including: residence corrections which allow large timesteps to be taken, electrostatic field solution with subgrid scale resolution of internal conductor boundaries, and a beat beam algorithm. Emphasis will be placed on new features and capabilities of the code, which include: a port to parallel processing environments, space-charge limited injection, and the linking of runs covering different sections of an accelerator. Representative applications in which the new features and capabilities are used will be presented along with the important results.

  7. Spacecraft charging analysis with the implicit particle-in-cell code iPic3D

    SciTech Connect

    Deca, J.; Lapenta, G.; Marchand, R.; Markidis, S.

    2013-10-15

    We present the first results on the analysis of spacecraft charging with the implicit particle-in-cell code iPic3D, designed for running on massively parallel supercomputers. The numerical algorithm is presented, highlighting the implementation of the electrostatic solver and the immersed boundary algorithm; the latter which creates the possibility to handle complex spacecraft geometries. As a first step in the verification process, a comparison is made between the floating potential obtained with iPic3D and with Orbital Motion Limited theory for a spherical particle in a uniform stationary plasma. Second, the numerical model is verified for a CubeSat benchmark by comparing simulation results with those of PTetra for space environment conditions with increasing levels of complexity. In particular, we consider spacecraft charging from plasma particle collection, photoelectron and secondary electron emission. The influence of a background magnetic field on the floating potential profile near the spacecraft is also considered. Although the numerical approaches in iPic3D and PTetra are rather different, good agreement is found between the two models, raising the level of confidence in both codes to predict and evaluate the complex plasma environment around spacecraft.

  8. The future of 3D and video coding in mobile and the internet

    NASA Astrophysics Data System (ADS)

    Bivolarski, Lazar

    2013-09-01

    The current Internet success has already changed our social and economic world and is still continuing to revolutionize the information exchange. The exponential increase of amount and types of data that is currently exchanged on the Internet represents significant challenge for the design of future architectures and solutions. This paper reviews the current status and trends in the design of solutions and research activities in the future Internet from point of view of managing the growth of bandwidth requirements and complexity of the multimedia that is being created and shared. Outlines the challenges that are present before the video coding and approaches to the design of standardized media formats and protocols while considering the expected convergence of multimedia formats and exchange interfaces. The rapid growth of connected mobile devices adds to the current and the future challenges in combination with the expected, in near future, arrival of multitude of connected devices. The new Internet technologies connecting the Internet of Things with wireless visual sensor networks and 3D virtual worlds requires conceptually new approaches of media content handling from acquisition to presentation in the 3D Media Internet. Accounting for the entire transmission system properties and enabling adaptation in real-time to context and content throughout the media proceeding path will be paramount in enabling the new media architectures as well as the new applications and services. The common video coding formats will need to be conceptually redesigned to allow for the implementation of the necessary 3D Media Internet features.

  9. Representation and coding of large-scale 3D dynamic maps

    NASA Astrophysics Data System (ADS)

    Cohen, Robert A.; Tian, Dong; Krivokuća, Maja; Sugimoto, Kazuo; Vetro, Anthony; Wakimoto, Koji; Sekiguchi, Shunichi

    2016-09-01

    combined with depth and color measurements of the surrounding environment. Localization could be achieved with GPS, inertial measurement units (IMU), cameras, or combinations of these and other devices, while the depth measurements could be achieved with time-of-flight, radar or laser scanning systems. The resulting 3D maps, which are composed of 3D point clouds with various attributes, could be used for a variety of applications, including finding your way around indoor spaces, navigating vehicles around a city, space planning, topographical surveying or public surveying of infrastructure and roads, augmented reality, immersive online experiences, and much more. This paper discusses application requirements related to the representation and coding of large-scale 3D dynamic maps. In particular, we address requirements related to different types of acquisition environments, scalability in terms of progressive transmission and efficiently rendering different levels of details, as well as key attributes to be included in the representation. Additionally, an overview of recently developed coding techniques is presented, including an assessment of current performance. Finally, technical challenges and needs for future standardization are discussed.

  10. PRONTO3D users` instructions: A transient dynamic code for nonlinear structural analysis

    SciTech Connect

    Attaway, S.W.; Mello, F.J.; Heinstein, M.W.; Swegle, J.W.; Ratner, J.A.; Zadoks, R.I.

    1998-06-01

    This report provides an updated set of users` instructions for PRONTO3D. PRONTO3D is a three-dimensional, transient, solid dynamics code for analyzing large deformations of highly nonlinear materials subjected to extremely high strain rates. This Lagrangian finite element program uses an explicit time integration operator to integrate the equations of motion. Eight-node, uniform strain, hexahedral elements and four-node, quadrilateral, uniform strain shells are used in the finite element formulation. An adaptive time step control algorithm is used to improve stability and performance in plasticity problems. Hourglass distortions can be eliminated without disturbing the finite element solution using either the Flanagan-Belytschko hourglass control scheme or an assumed strain hourglass control scheme. All constitutive models in PRONTO3D are cast in an unrotated configuration defined using the rotation determined from the polar decomposition of the deformation gradient. A robust contact algorithm allows for the impact and interaction of deforming contact surfaces of quite general geometry. The Smooth Particle Hydrodynamics method has been embedded into PRONTO3D using the contact algorithm to couple it with the finite element method.

  11. Calculation of the virtual current in an electromagnetic flow meter with one bubble using 3D model.

    PubMed

    Zhang, Xiao-Zhang; Li, Yantao

    2004-04-01

    Based on the theory of electromagnetic induction flow measurement, the Laplace equation in a complicated three-dimensional (3D) domain is solved by an alternating method. Virtual current potentials are obtained for an electromagnetic flow meter with one spherical bubble inside. The solutions are used to investigate the effects of bubble size and bubble position on the virtual current. Comparisons are done among the cases of 2D and 3D models, and of point electrode and large electrode. The results show that the 2D model overestimates the effect, while large electrodes are least sensitive to the bubble. This paper offers fundamentals for the study of the behavior of an electromagnetic flow meter in multiphase flow. For application, the results provide a possible way to estimate errors of the flow meter caused by multiphase flow.

  12. FURN3D: A computer code for radiative heat transfer in pulverized coal furnaces

    SciTech Connect

    Ahluwalia, R.K.; Im, K.H.

    1992-08-01

    A computer code FURN3D has been developed for assessing the impact of burning different coals on heat absorption pattern in pulverized coal furnaces. The code is unique in its ability to conduct detailed spectral calculations of radiation transport in furnaces fully accounting for the size distributions of char, soot and ash particles, ash content, and ash composition. The code uses a hybrid technique of solving the three-dimensional radiation transport equation for absorbing, emitting and anisotropically scattering media. The technique achieves an optimal mix of computational speed and accuracy by combining the discrete ordinate method (S[sub 4]), modified differential approximation (MDA) and P, approximation in different range of optical thicknesses. The code uses spectroscopic data for estimating the absorption coefficients of participating gases C0[sub 2], H[sub 2]0 and CO. It invokes Mie theory for determining the extinction and scattering coefficients of combustion particulates. The optical constants of char, soot and ash are obtained from dispersion relations derived from reflectivity, transmissivity and extinction measurements. A control-volume formulation is adopted for determining the temperature field inside the furnace. A simple char burnout model is employed for estimating heat release and evolution of particle size distribution. The code is written in Fortran 77, has modular form, and is machine-independent. The computer memory required by the code depends upon the number of grid points specified and whether the transport calculations are performed on spectral or gray basis.

  13. FURN3D: A computer code for radiative heat transfer in pulverized coal furnaces

    SciTech Connect

    Ahluwalia, R.K.; Im, K.H.

    1992-08-01

    A computer code FURN3D has been developed for assessing the impact of burning different coals on heat absorption pattern in pulverized coal furnaces. The code is unique in its ability to conduct detailed spectral calculations of radiation transport in furnaces fully accounting for the size distributions of char, soot and ash particles, ash content, and ash composition. The code uses a hybrid technique of solving the three-dimensional radiation transport equation for absorbing, emitting and anisotropically scattering media. The technique achieves an optimal mix of computational speed and accuracy by combining the discrete ordinate method (S{sub 4}), modified differential approximation (MDA) and P, approximation in different range of optical thicknesses. The code uses spectroscopic data for estimating the absorption coefficients of participating gases C0{sub 2}, H{sub 2}0 and CO. It invokes Mie theory for determining the extinction and scattering coefficients of combustion particulates. The optical constants of char, soot and ash are obtained from dispersion relations derived from reflectivity, transmissivity and extinction measurements. A control-volume formulation is adopted for determining the temperature field inside the furnace. A simple char burnout model is employed for estimating heat release and evolution of particle size distribution. The code is written in Fortran 77, has modular form, and is machine-independent. The computer memory required by the code depends upon the number of grid points specified and whether the transport calculations are performed on spectral or gray basis.

  14. Fast, automatic, and accurate catheter reconstruction in HDR brachytherapy using an electromagnetic 3D tracking system

    SciTech Connect

    Poulin, Eric; Racine, Emmanuel; Beaulieu, Luc; Binnekamp, Dirk

    2015-03-15

    Purpose: In high dose rate brachytherapy (HDR-B), current catheter reconstruction protocols are relatively slow and error prone. The purpose of this technical note is to evaluate the accuracy and the robustness of an electromagnetic (EM) tracking system for automated and real-time catheter reconstruction. Methods: For this preclinical study, a total of ten catheters were inserted in gelatin phantoms with different trajectories. Catheters were reconstructed using a 18G biopsy needle, used as an EM stylet and equipped with a miniaturized sensor, and the second generation Aurora{sup ®} Planar Field Generator from Northern Digital Inc. The Aurora EM system provides position and orientation value with precisions of 0.7 mm and 0.2°, respectively. Phantoms were also scanned using a μCT (GE Healthcare) and Philips Big Bore clinical computed tomography (CT) system with a spatial resolution of 89 μm and 2 mm, respectively. Reconstructions using the EM stylet were compared to μCT and CT. To assess the robustness of the EM reconstruction, five catheters were reconstructed twice and compared. Results: Reconstruction time for one catheter was 10 s, leading to a total reconstruction time inferior to 3 min for a typical 17-catheter implant. When compared to the μCT, the mean EM tip identification error was 0.69 ± 0.29 mm while the CT error was 1.08 ± 0.67 mm. The mean 3D distance error was found to be 0.66 ± 0.33 mm and 1.08 ± 0.72 mm for the EM and CT, respectively. EM 3D catheter trajectories were found to be more accurate. A maximum difference of less than 0.6 mm was found between successive EM reconstructions. Conclusions: The EM reconstruction was found to be more accurate and precise than the conventional methods used for catheter reconstruction in HDR-B. This approach can be applied to any type of catheters and applicators.

  15. A goal-oriented adaptive finite-element approach for plane wave 3-D electromagnetic modelling

    NASA Astrophysics Data System (ADS)

    Ren, Zhengyong; Kalscheuer, Thomas; Greenhalgh, Stewart; Maurer, Hansruedi

    2013-08-01

    We have developed a novel goal-oriented adaptive mesh refinement approach for finite-element methods to model plane wave electromagnetic (EM) fields in 3-D earth models based on the electric field differential equation. To handle complicated models of arbitrary conductivity, magnetic permeability and dielectric permittivity involving curved boundaries and surface topography, we employ an unstructured grid approach. The electric field is approximated by linear curl-conforming shape functions which guarantee the divergence-free condition of the electric field within each tetrahedron and continuity of the tangential component of the electric field across the interior boundaries. Based on the non-zero residuals of the approximated electric field and the yet to be satisfied boundary conditions of continuity of both the normal component of the total current density and the tangential component of the magnetic field strength across the interior interfaces, three a-posterior error estimators are proposed as a means to drive the goal-oriented adaptive refinement procedure. The first a-posterior error estimator relies on a combination of the residual of the electric field, the discontinuity of the normal component of the total current density and the discontinuity of the tangential component of the magnetic field strength across the interior faces shared by tetrahedra. The second a-posterior error estimator is expressed in terms of the discontinuity of the normal component of the total current density (conduction plus displacement current). The discontinuity of the tangential component of the magnetic field forms the third a-posterior error estimator. Analytical solutions for magnetotelluric (MT) and radiomagnetotelluric (RMT) fields impinging on a homogeneous half-space model are used to test the performances of the newly developed goal-oriented algorithms using the above three a-posterior error estimators. A trapezoidal topographical model, using normally incident EM waves

  16. Depth map coding using residual segmentation for 3D video system

    NASA Astrophysics Data System (ADS)

    Lee, Cheon; Ho, Yo-Sung

    2013-06-01

    Advanced 3D video systems employ multi-view video-plus-depth data to support the free-viewpoint navigation and comfortable 3D viewing; thus efficient depth map coding becomes an important issue. Unlike the color image, the depth map has a property that depth values of the inner part of an object are monotonic, but those of object boundaries change abruptly. Therefore, residual data generated by prediction errors around object boundaries consume many bits in depth map coding. Representing them with segment data can be better than the use of the conventional transformation around the boundary regions. In this paper, we propose an efficient depth map coding method using a residual segmentation instead of using transformation. The proposed residual segmentation divides residual data into two regions with a segment map and two mean values. If the encoder selects the proposed method in terms of rates, two quantized mean values and an index of the segment map are transmitted. Simulation results show significant gains of up to 10 dB compared to the state-of-the-art coders, such as JPEG2000 and H.264/AVC. [Figure not available: see fulltext.

  17. Efficient computational methods for electromagnetic imaging with applications to 3D magnetotellurics

    NASA Astrophysics Data System (ADS)

    Kordy, Michal Adam

    The motivation for this work is the forward and inverse problem for magnetotellurics, a frequency domain electromagnetic remote-sensing geophysical method used in mineral, geothermal, and groundwater exploration. The dissertation consists of four papers. In the first paper, we prove the existence and uniqueness of a representation of any vector field in H(curl) by a vector lying in H(curl) and H(div). It allows us to represent electric or magnetic fields by another vector field, for which nodal finite element approximation may be used in the case of non-constant electromagnetic properties. With this approach, the system matrix does not become ill-posed for low-frequency. In the second paper, we consider hexahedral finite element approximation of an electric field for the magnetotelluric forward problem. The near-null space of the system matrix for low frequencies makes the numerical solution unstable in the air. We show that the proper solution may obtained by applying a correction on the null space of the curl. It is done by solving a Poisson equation using discrete Helmholtz decomposition. We parallelize the forward code on multicore workstation with large RAM. In the next paper, we use the forward code in the inversion. Regularization of the inversion is done by using the second norm of the logarithm of conductivity. The data space Gauss-Newton approach allows for significant savings in memory and computational time. We show the efficiency of the method by considering a number of synthetic inversions and we apply it to real data collected in Cascade Mountains. The last paper considers a cross-frequency interpolation of the forward response as well as the Jacobian. We consider Pade approximation through model order reduction and rational Krylov subspace. The interpolating frequencies are chosen adaptively in order to minimize the maximum error of interpolation. Two error indicator functions are compared. We prove a theorem of almost always lucky failure in the

  18. 3-D geometry calibration and markerless electromagnetic tracking with a mobile C-arm

    NASA Astrophysics Data System (ADS)

    Cheryauka, Arvi; Barrett, Johnny; Wang, Zhonghua; Litvin, Andrew; Hamadeh, Ali; Beaudet, Daniel

    2007-03-01

    The design of mobile X-ray C-arm equipment with image tomography and surgical guidance capabilities involves the retrieval of repeatable gantry positioning in three-dimensional space. Geometry misrepresentations can cause degradation of the reconstruction results with the appearance of blurred edges, image artifacts, and even false structures. It may also amplify surgical instrument tracking errors leading to improper implant placement. In our prior publications we have proposed a C-arm 3D positioner calibration method comprising separate intrinsic and extrinsic geometry calibration steps. Following this approach, in the present paper, we extend the intrinsic geometry calibration of C-gantry beyond angular positions in the orbital plane into angular positions on a unit sphere of isocentric rotation. Our method makes deployment of markerless interventional tool guidance with use of high-resolution fluoro images and electromagnetic tracking feasible at any angular position of the tube-detector assembly. Variations of the intrinsic parameters associated with C-arm motion are measured off-line as functions of orbital and lateral angles. The proposed calibration procedure provides better accuracy, and prevents unnecessary workflow steps for surgical navigation applications. With a slight modification, the Misalignment phantom, a tool for intrinsic geometry calibration, is also utilized to obtain an accurate 'image-to-sensor' mapping. We show simulation results, image quality and navigation accuracy estimates, and feasibility data acquired with the prototype system. The experimental results show the potential of high-resolution CT imaging (voxel size below 0.5 mm) and confident navigation in an interventional surgery setting with a mobile C-arm.

  19. 3-D localization of gamma ray sources with coded apertures for medical applications

    NASA Astrophysics Data System (ADS)

    Kaissas, I.; Papadimitropoulos, C.; Karafasoulis, K.; Potiriadis, C.; Lambropoulos, C. P.

    2015-09-01

    Several small gamma cameras for radioguided surgery using CdTe or CdZnTe have parallel or pinhole collimators. Coded aperture imaging is a well-known method for gamma ray source directional identification, applied in astrophysics mainly. The increase in efficiency due to the substitution of the collimators by the coded masks renders the method attractive for gamma probes used in radioguided surgery. We have constructed and operationally verified a setup consisting of two CdTe gamma cameras with Modified Uniform Redundant Array (MURA) coded aperture masks of rank 7 and 19 and a video camera. The 3-D position of point-like radioactive sources is estimated via triangulation using decoded images acquired by the gamma cameras. We have also developed code for both fast and detailed simulations and we have verified the agreement between experimental results and simulations. In this paper we present a simulation study for the spatial localization of two point sources using coded aperture masks with rank 7 and 19.

  20. Newly-Developed 3D GRMHD Code and its Application to Jet Formation

    NASA Technical Reports Server (NTRS)

    Mizuno, Y.; Nishikawa, K.-I.; Koide, S.; Hardee, P.; Fishman, G. J.

    2006-01-01

    We have developed a new three-dimensional general relativistic magnetohydrodynamic code by using a conservative, high-resolution shock-capturing scheme. The numerical fluxes are calculated using the HLL approximate Riemann solver scheme. The flux-interpolated constrained transport scheme is used to maintain a divergence-free magnetic field. We have performed various 1-dimensional test problems in both special and general relativity by using several reconstruction methods and found that the new 3D GRMHD code shows substantial improvements over our previous model. The . preliminary results show the jet formations from a geometrically thin accretion disk near a non-rotating and a rotating black hole. We will discuss the jet properties depended on the rotation of a black hole and the magnetic field strength.

  1. Implementation of the 3D edge plasma code EMC3-EIRENE on NSTX

    DOE PAGES

    Lore, J. D.; Canik, J. M.; Feng, Y.; ...

    2012-05-09

    The 3D edge transport code EMC3-EIRENE has been applied for the first time to the NSTX spherical tokamak. A new disconnected double null grid has been developed to allow the simulation of plasma where the radial separation of the inner and outer separatrix is less than characteristic widths (e.g. heat flux width) at the midplane. Modelling results are presented for both an axisymmetric case and a case where 3D magnetic field is applied in an n = 3 configuration. In the vacuum approximation, the perturbed field consists of a wide region of destroyed flux surfaces and helical lobes which aremore » a mixture of long and short connection length field lines formed by the separatrix manifolds. This structure is reflected in coupled 3D plasma fluid (EMC3) and kinetic neutral particle (EIRENE) simulations. The helical lobes extending inside of the unperturbed separatrix are filled in by hot plasma from the core. The intersection of the lobes with the divertor results in a striated flux footprint pattern on the target plates. As a result, profiles of divertor heat and particle fluxes are compared with experimental data, and possible sources of discrepancy are discussed.« less

  2. Recent Developments in the VISRAD 3-D Target Design and Radiation Simulation Code

    NASA Astrophysics Data System (ADS)

    Macfarlane, Joseph; Woodruff, P.; Golovkin, I.

    2011-10-01

    The 3-D view factor code VISRAD is widely used in designing HEDP experiments at major laser and pulsed-power facilities, including NIF, OMEGA, OMEGA-EP, ORION, Z, and PLX. It simulates target designs by generating a 3-D grid of surface elements, utilizing a variety of 3-D primitives and surface removal algorithms, and can be used to compute the radiation flux throughout the surface element grid by computing element-to-element view factors and solving power balance equations. Target set-up and beam pointing are facilitated by allowing users to specify positions and angular orientations using a variety of coordinates systems (e . g . , that of any laser beam, target component, or diagnostic port). Analytic modeling for laser beam spatial profiles for OMEGA DPPs and NIF CPPs is used to compute laser intensity profiles throughout the grid of surface elements. VISRAD includes a variety of user-friendly graphics for setting up targets and displaying results, can readily display views from any point in space, and can be used to generate image sequences for animations. We will discuss recent improvements to the software package and plans for future developments.

  3. Implementation of the 3D edge plasma code EMC3-EIRENE on NSTX

    SciTech Connect

    Lore, J. D.; Canik, J. M.; Feng, Y.; Ahn, J. -W.; Maingi, R.; Soukhanovskii, V.

    2012-05-09

    The 3D edge transport code EMC3-EIRENE has been applied for the first time to the NSTX spherical tokamak. A new disconnected double null grid has been developed to allow the simulation of plasma where the radial separation of the inner and outer separatrix is less than characteristic widths (e.g. heat flux width) at the midplane. Modelling results are presented for both an axisymmetric case and a case where 3D magnetic field is applied in an n = 3 configuration. In the vacuum approximation, the perturbed field consists of a wide region of destroyed flux surfaces and helical lobes which are a mixture of long and short connection length field lines formed by the separatrix manifolds. This structure is reflected in coupled 3D plasma fluid (EMC3) and kinetic neutral particle (EIRENE) simulations. The helical lobes extending inside of the unperturbed separatrix are filled in by hot plasma from the core. The intersection of the lobes with the divertor results in a striated flux footprint pattern on the target plates. As a result, profiles of divertor heat and particle fluxes are compared with experimental data, and possible sources of discrepancy are discussed.

  4. Embedded 3D shape measurement system based on a novel spatio-temporal coding method

    NASA Astrophysics Data System (ADS)

    Xu, Bin; Tian, Jindong; Tian, Yong; Li, Dong

    2016-11-01

    Structured light measurement has been wildly used since 1970s in industrial component detection, reverse engineering, 3D molding, robot navigation, medical and many other fields. In order to satisfy the demand for high speed, high precision and high resolution 3-D measurement for embedded system, a new patterns combining binary and gray coding principle in space are designed and projected onto the object surface orderly. Each pixel corresponds to the designed sequence of gray values in time - domain, which is treated as a feature vector. The unique gray vector is then dimensionally reduced to a scalar which could be used as characteristic information for binocular matching. In this method, the number of projected structured light patterns is reduced, and the time-consuming phase unwrapping in traditional phase shift methods is avoided. This algorithm is eventually implemented on DM3730 embedded system for 3-D measuring, which consists of an ARM and a DSP core and has a strong capability of digital signal processing. Experimental results demonstrated the feasibility of the proposed method.

  5. Using 3D Simulation of Elastic Wave Propagation in Laplace Domain for Electromagnetic-Seismic Inverse Modeling

    NASA Astrophysics Data System (ADS)

    Petrov, P.; Newman, G. A.

    2010-12-01

    -Fourier domain we had developed 3D code for full-wave field simulation in the elastic media which take into account nonlinearity introduced by free-surface effects. Our approach is based on the velocity-stress formulation. In the contrast to conventional formulation we defined the material properties such as density and Lame constants not at nodal points but within cells. This second order finite differences method formulated in the cell-based grid, generate numerical solutions compatible with analytical ones within the range errors determinate by dispersion analysis. Our simulator will be embedded in an inversion scheme for joint seismic- electromagnetic imaging. It also offers possibilities for preconditioning the seismic wave propagation problems in the frequency domain. References. Shin, C. & Cha, Y. (2009), Waveform inversion in the Laplace-Fourier domain, Geophys. J. Int. 177(3), 1067- 1079. Shin, C. & Cha, Y. H. (2008), Waveform inversion in the Laplace domain, Geophys. J. Int. 173(3), 922-931. Commer, M. & Newman, G. (2008), New advances in three-dimensional controlled-source electromagnetic inversion, Geophys. J. Int. 172(2), 513-535. Newman, G. A., Commer, M. & Carazzone, J. J. (2010), Imaging CSEM data in the presence of electrical anisotropy, Geophysics, in press.

  6. Radiation Coupling with the FUN3D Unstructured-Grid CFD Code

    NASA Technical Reports Server (NTRS)

    Wood, William A.

    2012-01-01

    The HARA radiation code is fully-coupled to the FUN3D unstructured-grid CFD code for the purpose of simulating high-energy hypersonic flows. The radiation energy source terms and surface heat transfer, under the tangent slab approximation, are included within the fluid dynamic ow solver. The Fire II flight test, at the Mach-31 1643-second trajectory point, is used as a demonstration case. Comparisons are made with an existing structured-grid capability, the LAURA/HARA coupling. The radiative surface heat transfer rates from the present approach match the benchmark values within 6%. Although radiation coupling is the focus of the present work, convective surface heat transfer rates are also reported, and are seen to vary depending upon the choice of mesh connectivity and FUN3D ux reconstruction algorithm. On a tetrahedral-element mesh the convective heating matches the benchmark at the stagnation point, but under-predicts by 15% on the Fire II shoulder. Conversely, on a mixed-element mesh the convective heating over-predicts at the stagnation point by 20%, but matches the benchmark away from the stagnation region.

  7. Development and preliminary verification of the 3D core neutronic code: COCO

    SciTech Connect

    Lu, H.; Mo, K.; Li, W.; Bai, N.; Li, J.

    2012-07-01

    As the recent blooming economic growth and following environmental concerns (China)) is proactively pushing forward nuclear power development and encouraging the tapping of clean energy. Under this situation, CGNPC, as one of the largest energy enterprises in China, is planning to develop its own nuclear related technology in order to support more and more nuclear plants either under construction or being operation. This paper introduces the recent progress in software development for CGNPC. The focus is placed on the physical models and preliminary verification results during the recent development of the 3D Core Neutronic Code: COCO. In the COCO code, the non-linear Green's function method is employed to calculate the neutron flux. In order to use the discontinuity factor, the Neumann (second kind) boundary condition is utilized in the Green's function nodal method. Additionally, the COCO code also includes the necessary physical models, e.g. single-channel thermal-hydraulic module, burnup module, pin power reconstruction module and cross-section interpolation module. The preliminary verification result shows that the COCO code is sufficient for reactor core design and analysis for pressurized water reactor (PWR). (authors)

  8. Induced Polarization with Electromagnetic Coupling: 3D Spectral Imaging Theory, EMSP Project No. 73836

    SciTech Connect

    Morgan, F. Dale; Sogade, John

    2004-12-14

    This project was designed as a broad foundational study of spectral induced polarization (SIP) for characterization of contaminated sites. It encompassed laboratory studies of the effects of chemistry on induced polarization, development of 3D forward modeling and inversion codes, and investigations of inductive and capacitive coupling problems. In the laboratory part of the project a physico-chemical model developed in this project was used to invert laboratory IP spectra for the grain size and the effective grain size distribution of the sedimentary rocks as well as the formation factor, porosity, specific surface area, and the apparent fractal dimension. Furthermore, it was established that the IP response changed with the solution chemistry, the concentration of a given solution chemistry, valence of the constituent ions, and ionic radius. In the field part of the project, a 3D complex forward and inverse model was developed. It was used to process data acquired at two frequencies (1/16 Hz and 1/ 4Hz) in a cross-borehole configuration at the A-14 outfall area of the Savannah River Site (SRS) during March 2003 and June 2004. The chosen SRS site was contaminated with Tetrachloroethylene (TCE) and Trichloroethylene (PCE) that were disposed in this area for several decades till the 1980s. The imaginary conductivity produced from the inverted 2003 data correlated very well with the log10 (PCE) concentration derived from point sampling at 1 ft spacing in five ground-truth boreholes drilled after the data acquisition. The equivalent result for the 2004 data revealed that there were significant contaminant movements during the period March 2003 and June 2004, probably related to ground-truth activities and nearby remediation activities. Therefore SIP was successfully used to develop conceptual models of volume distributions of PCE/TCE contamination. In addition, the project developed non-polarizing electrodes that can be deployed in boreholes for years. A total of 28

  9. New 3D parallel GILD electromagnetic modeling and nonlinear inversion using global magnetic integral and local differential equation

    SciTech Connect

    Xie, G.; Li, J.; Majer, E.; Zuo, D.

    1998-07-01

    This paper describes a new 3D parallel GILD electromagnetic (EM) modeling and nonlinear inversion algorithm. The algorithm consists of: (a) a new magnetic integral equation instead of the electric integral equation to solve the electromagnetic forward modeling and inverse problem; (b) a collocation finite element method for solving the magnetic integral and a Galerkin finite element method for the magnetic differential equations; (c) a nonlinear regularizing optimization method to make the inversion stable and of high resolution; and (d) a new parallel 3D modeling and inversion using a global integral and local differential domain decomposition technique (GILD). The new 3D nonlinear electromagnetic inversion has been tested with synthetic data and field data. The authors obtained very good imaging for the synthetic data and reasonable subsurface EM imaging for the field data. The parallel algorithm has high parallel efficiency over 90% and can be a parallel solver for elliptic, parabolic, and hyperbolic modeling and inversion. The parallel GILD algorithm can be extended to develop a high resolution and large scale seismic and hydrology modeling and inversion in the massively parallel computer.

  10. Code verification for unsteady 3-D fluid-solid interaction problems

    NASA Astrophysics Data System (ADS)

    Yu, Kintak Raymond; Étienne, Stéphane; Hay, Alexander; Pelletier, Dominique

    2015-12-01

    This paper describes a procedure to synthesize Manufactured Solutions for Code Verification of an important class of Fluid-Structure Interaction (FSI) problems whose behaviors can be modeled as rigid body vibrations in incompressible fluids. We refer this class of FSI problems as Fluid-Solid Interaction problems, which can be found in many practical engineering applications. The methodology can be utilized to develop Manufactured Solutions for both 2-D and 3-D cases. We demonstrate the procedure with our numerical code. We present details of the formulation and methodology. We also provide the reasonings behind our proposed approach. Results from grid and time step refinement studies confirm the verification of our solver and demonstrate the versatility of the simple synthesis procedure. In addition, the results also demonstrate that the modified decoupled approach to verify flow problems with high-order time-stepping schemes can be employed equally well to verify code for multi-physics problems (here, those of the Fluid-Solid Interaction) when the numerical discretization is based on the Method of Lines.

  11. Using self-similarity compensation for improving inter-layer prediction in scalable 3D holoscopic video coding

    NASA Astrophysics Data System (ADS)

    Conti, Caroline; Nunes, Paulo; Ducla Soares, Luís.

    2013-09-01

    Holoscopic imaging, also known as integral imaging, has been recently attracting the attention of the research community, as a promising glassless 3D technology due to its ability to create a more realistic depth illusion than the current stereoscopic or multiview solutions. However, in order to gradually introduce this technology into the consumer market and to efficiently deliver 3D holoscopic content to end-users, backward compatibility with legacy displays is essential. Consequently, to enable 3D holoscopic content to be delivered and presented on legacy displays, a display scalable 3D holoscopic coding approach is required. Hence, this paper presents a display scalable architecture for 3D holoscopic video coding with a three-layer approach, where each layer represents a different level of display scalability: Layer 0 - a single 2D view; Layer 1 - 3D stereo or multiview; and Layer 2 - the full 3D holoscopic content. In this context, a prediction method is proposed, which combines inter-layer prediction, aiming to exploit the existing redundancy between the multiview and the 3D holoscopic layers, with self-similarity compensated prediction (previously proposed by the authors for non-scalable 3D holoscopic video coding), aiming to exploit the spatial redundancy inherent to the 3D holoscopic enhancement layer. Experimental results show that the proposed combined prediction can improve significantly the rate-distortion performance of scalable 3D holoscopic video coding with respect to the authors' previously proposed solutions, where only inter-layer or only self-similarity prediction is used.

  12. Liner Optimization Studies Using the Ducted Fan Noise Prediction Code TBIEM3D

    NASA Technical Reports Server (NTRS)

    Dunn, M. H.; Farassat, F.

    1998-01-01

    In this paper we demonstrate the usefulness of the ducted fan noise prediction code TBIEM3D as a liner optimization design tool. Boundary conditions on the interior duct wall allow for hard walls or a locally reacting liner with axially segmented, circumferentially uniform impedance. Two liner optimization studies are considered in which farfield noise attenuation due to the presence of a liner is maximized by adjusting the liner impedance. In the first example, the dependence of optimal liner impedance on frequency and liner length is examined. Results show that both the optimal impedance and attenuation levels are significantly influenced by liner length and frequency. In the second example, TBIEM3D is used to compare radiated sound pressure levels between optimal and non-optimal liner cases at conditions designed to simulate take-off. It is shown that significant noise reduction is achieved for most of the sound field by selecting the optimal or near optimal liner impedance. Our results also indicate that there is relatively large region of the impedance plane over which optimal or near optimal liner behavior is attainable. This is an important conclusion for the designer since there are variations in liner characteristics due to manufacturing imprecisions.

  13. An Object-Oriented Approach to Writing Computational Electromagnetics Codes

    NASA Technical Reports Server (NTRS)

    Zimmerman, Martin; Mallasch, Paul G.

    1996-01-01

    Presently, most computer software development in the Computational Electromagnetics (CEM) community employs the structured programming paradigm, particularly using the Fortran language. Other segments of the software community began switching to an Object-Oriented Programming (OOP) paradigm in recent years to help ease design and development of highly complex codes. This paper examines design of a time-domain numerical analysis CEM code using the OOP paradigm, comparing OOP code and structured programming code in terms of software maintenance, portability, flexibility, and speed.

  14. Lossless data compression studies for NOAA hyperspectral environmental suite using 3D integer wavelet transforms with 3D embedded zerotree coding

    NASA Astrophysics Data System (ADS)

    Huang, Bormin; Huang, Hung-Lung; Chen, Hao; Ahuja, Alok; Baggett, Kevin; Schmit, Timothy J.; Heymann, Roger W.

    2003-09-01

    Hyperspectral sounder data is a particular class of data that requires high accuracy for useful retrieval of atmospheric temperature and moisture profiles, surface characteristics, cloud properties, and trace gas information. Therefore compression of these data sets is better to be lossless or near lossless. The next-generation NOAA/NESDIS GOES-R hyperspectral sounder, now referred to as the HES (Hyperspectral Environmental Suite), will have hyperspectral resolution (over one thousand channels with spectral widths on the order of 0.5 wavenumber) and high spatial resolution (less than 10 km). Given the large volume of three-dimensional hyperspectral sounder data that will be generated by the HES instrument, the use of robust data compression techniques will be beneficial to data transfer and archive. In this paper, we study lossless data compression for the HES using 3D integer wavelet transforms via the lifting schemes. The wavelet coefficients are then processed with the 3D embedded zerotree wavelet (EZW) algorithm followed by context-based arithmetic coding. We extend the 3D EZW scheme to take on any size of 3D satellite data, each of whose dimensions need not be divisible by 2N, where N is the levels of the wavelet decomposition being performed. The compression ratios of various kinds of wavelet transforms are presented along with a comparison with the JPEG2000 codec.

  15. Loop heating by D.C. electric current and electromagnetic wave emissions simulated by 3-D EM particle zone

    NASA Technical Reports Server (NTRS)

    Sakai, J. I.; Zhao, J.; Nishikawa, K.-I.

    1994-01-01

    We have shown that a current-carrying plasma loop can be heated by magnetic pinch driven by the pressure imbalance between inside and outside the loop, using a 3-dimensional electromagnetic (EM) particle code. Both electrons and ions in the loop can be heated in the direction perpendicular to the ambient magnetic field, therefore the perpendicular temperature can be increased about 10 times compared with the parallel temperature. This temperature anisotropy produced by the magnetic pinch heating can induce a plasma instability, by which high-frequency electromagnetic waves can be excited. The plasma current which is enhanced by the magnetic pinch can also excite a kinetic kink instability, which can heat ions perpendicular to the magnetic field. The heating mechanism of ions as well as the electromagnetic emission could be important for an understanding of the coronal loop heating and the electromagnetic wave emissions from active coronal regions.

  16. The 3D MHD code GOEMHD3 for astrophysical plasmas with large Reynolds numbers. Code description, verification, and computational performance

    NASA Astrophysics Data System (ADS)

    Skála, J.; Baruffa, F.; Büchner, J.; Rampp, M.

    2015-08-01

    Context. The numerical simulation of turbulence and flows in almost ideal astrophysical plasmas with large Reynolds numbers motivates the implementation of magnetohydrodynamical (MHD) computer codes with low resistivity. They need to be computationally efficient and scale well with large numbers of CPU cores, allow obtaining a high grid resolution over large simulation domains, and be easily and modularly extensible, for instance, to new initial and boundary conditions. Aims: Our aims are the implementation, optimization, and verification of a computationally efficient, highly scalable, and easily extensible low-dissipative MHD simulation code for the numerical investigation of the dynamics of astrophysical plasmas with large Reynolds numbers in three dimensions (3D). Methods: The new GOEMHD3 code discretizes the ideal part of the MHD equations using a fast and efficient leap-frog scheme that is second-order accurate in space and time and whose initial and boundary conditions can easily be modified. For the investigation of diffusive and dissipative processes the corresponding terms are discretized by a DuFort-Frankel scheme. To always fulfill the Courant-Friedrichs-Lewy stability criterion, the time step of the code is adapted dynamically. Numerically induced local oscillations are suppressed by explicit, externally controlled diffusion terms. Non-equidistant grids are implemented, which enhance the spatial resolution, where needed. GOEMHD3 is parallelized based on the hybrid MPI-OpenMP programing paradigm, adopting a standard two-dimensional domain-decomposition approach. Results: The ideal part of the equation solver is verified by performing numerical tests of the evolution of the well-understood Kelvin-Helmholtz instability and of Orszag-Tang vortices. The accuracy of solving the (resistive) induction equation is tested by simulating the decay of a cylindrical current column. Furthermore, we show that the computational performance of the code scales very

  17. Validation of Heat Transfer and Film Cooling Capabilities of the 3-D RANS Code TURBO

    NASA Technical Reports Server (NTRS)

    Shyam, Vikram; Ameri, Ali; Chen, Jen-Ping

    2010-01-01

    The capabilities of the 3-D unsteady RANS code TURBO have been extended to include heat transfer and film cooling applications. The results of simulations performed with the modified code are compared to experiment and to theory, where applicable. Wilcox s k-turbulence model has been implemented to close the RANS equations. Two simulations are conducted: (1) flow over a flat plate and (2) flow over an adiabatic flat plate cooled by one hole inclined at 35 to the free stream. For (1) agreement with theory is found to be excellent for heat transfer, represented by local Nusselt number, and quite good for momentum, as represented by the local skin friction coefficient. This report compares the local skin friction coefficients and Nusselt numbers on a flat plate obtained using Wilcox's k-model with the theory of Blasius. The study looks at laminar and turbulent flows over an adiabatic flat plate and over an isothermal flat plate for two different wall temperatures. It is shown that TURBO is able to accurately predict heat transfer on a flat plate. For (2) TURBO shows good qualitative agreement with film cooling experiments performed on a flat plate with one cooling hole. Quantitatively, film effectiveness is under predicted downstream of the hole.

  18. Quantum self-correction in the 3D cubic code model.

    PubMed

    Bravyi, Sergey; Haah, Jeongwan

    2013-11-15

    A big open question in the quantum information theory concerns the feasibility of a self-correcting quantum memory. A quantum state recorded in such memory can be stored reliably for a macroscopic time without need for active error correction, if the memory is in contact with a cold enough thermal bath. Here we report analytic and numerical evidence for self-correcting behavior in the quantum spin lattice model known as the 3D cubic code. We prove that its memory time is at least L(cβ), where L is the lattice size, β is the inverse temperature of the bath, and c>0 is a constant coefficient. However, this bound applies only if the lattice size L does not exceed a critical value which grows exponentially with β. In that sense, the model can be called a partially self-correcting memory. We also report a Monte Carlo simulation indicating that our analytic bounds on the memory time are tight up to constant coefficients. To model the readout step we introduce a new decoding algorithm, which can be implemented efficiently for any topological stabilizer code. A longer version of this work can be found in Bravyi and Haah, arXiv:1112.3252.

  19. 3D Airborne Electromagnetic Inversion: A case study from the Musgrave Region, South Australia

    NASA Astrophysics Data System (ADS)

    Cox, L. H.; Wilson, G. A.; Zhdanov, M. S.; Sunwall, D. A.

    2012-12-01

    Geophysicists know and accept that geology is inherently 3D, and is resultant from complex, overlapping processes related to genesis, metamorphism, deformation, alteration, weathering, and/or hydrogeology. Yet, the geophysics community has long relied on qualitative analysis, conductivity depth imaging (CDIs), 1D inversion, and/or plate modeling. There are many reasons for this deficiency, not the least of which has been the lack of capacity for historic 3D AEM inversion algorithms to invert entire surveys so as to practically affect exploration decisions. Our recent introduction of a moving sensitivity domain (footprint) methodology has been a paradigm shift in AEM interpretation. The basis of this method is that one needs only to calculate the responses and sensitivities for that part of the 3D earth model that is within the AEM system's sensitivity domain (footprint), and then superimpose all sensitivity domains into a single, sparse sensitivity matrix for the entire 3D earth model which is then updated in a regularized inversion scheme. This has made it practical to rigorously invert entire surveys with thousands of line kilometers of AEM data to mega-cell 3D models in hours using multi-processor workstations. Since 2010, over eighty individual projects have been completed for Aerodat, AEROTEM, DIGHEM, GEOTEM, HELITEM, HoisTEM, MEGATEM, RepTEM, RESOLVE, SkyTEM, SPECTREM, TEMPEST, and VTEM data from Australia, Brazil, Canada, Finland, Ghana, Peru, Tanzania, the US, and Zambia. Examples of 3D AEM inversion have been published for a variety of applications, including mineral exploration, oil sands exploration, salinity, permafrost, and bathymetry mapping. In this paper, we present a comparison of 3D inversions for SkyTEM, SPECTREM, TEMPET and VTEM data acquired over the same area in the Musgrave region of South Australia for exploration under cover.

  20. Structured Light Based 3d Scanning for Specular Surface by the Combination of Gray Code and Phase Shifting

    NASA Astrophysics Data System (ADS)

    Zhang, Yujia; Yilmaz, Alper

    2016-06-01

    Surface reconstruction using coded structured light is considered one of the most reliable techniques for high-quality 3D scanning. With a calibrated projector-camera stereo system, a light pattern is projected onto the scene and imaged by the camera. Correspondences between projected and recovered patterns are computed in the decoding process, which is used to generate 3D point cloud of the surface. However, the indirect illumination effects on the surface, such as subsurface scattering and interreflections, will raise the difficulties in reconstruction. In this paper, we apply maximum min-SW gray code to reduce the indirect illumination effects of the specular surface. We also analysis the errors when comparing the maximum min-SW gray code and the conventional gray code, which justifies that the maximum min-SW gray code has significant superiority to reduce the indirect illumination effects. To achieve sub-pixel accuracy, we project high frequency sinusoidal patterns onto the scene simultaneously. But for specular surface, the high frequency patterns are susceptible to decoding errors. Incorrect decoding of high frequency patterns will result in a loss of depth resolution. Our method to resolve this problem is combining the low frequency maximum min-SW gray code and the high frequency phase shifting code, which achieves dense 3D reconstruction for specular surface. Our contributions include: (i) A complete setup of the structured light based 3D scanning system; (ii) A novel combination technique of the maximum min-SW gray code and phase shifting code. First, phase shifting decoding with sub-pixel accuracy. Then, the maximum min-SW gray code is used to resolve the ambiguity resolution. According to the experimental results and data analysis, our structured light based 3D scanning system enables high quality dense reconstruction of scenes with a small number of images. Qualitative and quantitative comparisons are performed to extract the advantages of our new

  1. Mechanical and electromagnetic properties of 3D printed hot pressed nanocarbon/poly(lactic) acid thin films

    NASA Astrophysics Data System (ADS)

    Kotsilkova, R.; Ivanov, E.; Todorov, P.; Petrova, I.; Volynets, N.; Paddubskaya, A.; Kuzhir, P.; Uglov, V.; Biró, I.; Kertész, K.; Márk, G. I.; Biró, L. P.

    2017-02-01

    We constructed a new type of light-weight, nanocarbon based thin film material having good mechanical properties, thermal stability, and electromagnetic shielding efficiency. Our method, 3D printing combined with hot pressing, is a cheap and industrially upscalable process. First a sandwich structure was created by layer-to-layer deposition of alternating 100 μm thick nanocarbon containing plastic layers and 100 μm thick pristine plastic layers, repeated as building blocks. The 3D printed samples were hot pressed to obtain thin films of 10-30 μm thickness. We used a commercial nanocarbon 3D printing filament (Black Magic). TEM investigations revealed the nanocarbon filler to be a mixture of graphene sheets, short carbon nanotubes, fishbone nanotubes, graphitic nanoparticles, and carbon black. Small-angle X-ray scattering and X-ray diffraction studies showed some amorphization of the nanocarbon filler as a consequence of the hot pressing. The nanoindentation hardness, nanoscratch hardness, and Young's modulus increase gradually by increasing the number of layers in the films, due to an increase of the amount of nanocarbon filler. Microwave absorption also increases continuously with the number of nanocarbon layers, reaching 40% for 3 nanocarbon layers. We demonstrate that unlike most conventional composites loaded with nanocarbons having pronounced dielectric properties, when the real part of permittivity Re(ɛ) is much higher than its imaginary part Im(ɛ) at high frequencies, a combination of 3D printing and hot pressing allows the fabrication of composites with Re ɛ ≈ Im ɛ in a very broad frequency range (0.2-0.6 THz). Our new 3D printed—hot pressed thin films may compete with the CVD graphene sandwiches in electromagnetic shielding applications because of their easier processability and low cost.

  2. Boundary element solutions for broad-band 3-D geo-electromagnetic problems accelerated by an adaptive multilevel fast multipole method

    NASA Astrophysics Data System (ADS)

    Ren, Zhengyong; Kalscheuer, Thomas; Greenhalgh, Stewart; Maurer, Hansruedi

    2013-02-01

    We have developed a generalized and stable surface integral formula for 3-D uniform inducing field and plane wave electromagnetic induction problems, which works reliably over a wide frequency range. Vector surface electric currents and magnetic currents, scalar surface electric charges and magnetic charges are treated as the variables. This surface integral formula is successfully applied to compute the electromagnetic responses of 3-D topography to low frequency magnetotelluric and high frequency radio-magnetotelluric fields. The standard boundary element method which is used to solve this surface integral formula quickly exceeds the memory capacity of modern computers for problems involving hundreds of thousands of unknowns. To make the surface integral formulation applicable and capable of dealing with large-scale 3-D geo-electromagnetic problems, we have developed a matrix-free adaptive multilevel fast multipole boundary element solver. By means of the fast multipole approach, the time-complexity of solving the final system of linear equations is reduced to O(m log m) and the memory cost is reduced to O(m), where m is the number of unknowns. The analytical solutions for a half-space model were used to verify our numerical solutions over the frequency range 0.001-300 kHz. In addition, our numerical solution shows excellent agreement with a published numerical solution for an edge-based finite-element method on a trapezoidal hill model at a frequency of 2 Hz. Then, a high frequency simulation for a similar trapezoidal hill model was used to study the effects of displacement currents in the radio-magnetotelluric frequency range. Finally, the newly developed algorithm was applied to study the effect of moderate topography and to evaluate the applicability of a 2-D RMT inversion code that assumes a flat air-Earth interface, on RMT field data collected at Smørgrav, southern Norway. This paper constitutes the first part of a hybrid boundary element-finite element

  3. ORBXYZ: a 3D single-particle orbit code for following charged-particle trajectories in equilibrium magnetic fields

    SciTech Connect

    Anderson, D.V.; Cohen, R.H.; Ferguson, J.R.; Johnston, B.M.; Sharp, C.B.; Willmann, P.A.

    1981-06-30

    The single particle orbit code, TIBRO, has been modified extensively to improve the interpolation methods used and to allow use of vector potential fields in the simulation of charged particle orbits on a 3D domain. A 3D cubic B-spline algorithm is used to generate spline coefficients used in the interpolation. Smooth and accurate field representations are obtained. When vector potential fields are used, the 3D cubic spline interpolation formula analytically generates the magnetic field used to push the particles. This field has del.BETA = 0 to computer roundoff. When magnetic induction is used the interpolation allows del.BETA does not equal 0, which can lead to significant nonphysical results. Presently the code assumes quadrupole symmetry, but this is not an essential feature of the code and could be easily removed for other applications. Many details pertaining to this code are given on microfiche accompanying this report.

  4. Rare meshes FEM scheme for quasi-stationary electromagnetic fields determination 3D problems

    NASA Astrophysics Data System (ADS)

    Chekmarev, D. T.; Kalinin, A. V.; Sadovsky, V. V.; Tiukhtina, A. A.

    2016-11-01

    The initial-boundary value problem for the quasi-stationary magnetic approximation of the Maxwell equations in inhomogeneous media is studied. The considered problem is reduced to the variational problem of determining the vector magnetic potential. The special gauge for vector magnetic and scalar electrical potentials is used. The well-posedness of the problems is established under general conditions on the coefficients and the applicability of the projection methods for these problems is validated. For the numerical solution of this problem provides to use the effective rare mesh FEM scheme for 3D problems. This scheme is well- proven in 3D elasticity and plasticity problems solving.

  5. Accurate, full chip 3D electromagnetic field model for non-Manhattan mask corners

    NASA Astrophysics Data System (ADS)

    Lam, Michael; Clifford, Chris; Oliver, Michael; Fryer, David; Tejnil, Edita; Adam, Kostas

    2015-03-01

    The physical process of mask manufacturing produces absorber geometry with significantly less than 90 degree fidelity at corners. The non-Manhattan mask geometry is an essential contributor to the aerial image and resulting patterning performance through focus. Current state of the art models for corner rounding employ "chopping" a 90 degree mask corner, replacing the corner with a small 45 degree edge. In this paper, a methodology is presented to approximate the impact of 3D EMF effects introduced by corners with rounded edges. The approach is integrated into a full chip 3D mask simulation methodology based on the Domain Decomposition Method (DDM) with edge to edge crosstalk correction.

  6. Para: a computer simulation code for plasma driven electromagnetic launchers

    SciTech Connect

    Thio, Y.-C.

    1983-03-01

    A computer code for simulation of rail-type accelerators utilizing a plasma armature has been developed and is described in detail. Some time varying properties of the plasma are taken into account in this code thus allowing the development of a dynamical model of the behavior of a plasma in a rail-type electromagnetic launcher. The code is being successfully used to predict and analyse experiments on small calibre rail-gun launchers.

  7. TOMO3D: 3-D joint refraction and reflection traveltime tomography parallel code for active-source seismic data—synthetic test

    NASA Astrophysics Data System (ADS)

    Meléndez, A.; Korenaga, J.; Sallarès, V.; Miniussi, A.; Ranero, C. R.

    2015-10-01

    We present a new 3-D traveltime tomography code (TOMO3D) for the modelling of active-source seismic data that uses the arrival times of both refracted and reflected seismic phases to derive the velocity distribution and the geometry of reflecting boundaries in the subsurface. This code is based on its popular 2-D version TOMO2D from which it inherited the methods to solve the forward and inverse problems. The traveltime calculations are done using a hybrid ray-tracing technique combining the graph and bending methods. The LSQR algorithm is used to perform the iterative regularized inversion to improve the initial velocity and depth models. In order to cope with an increased computational demand due to the incorporation of the third dimension, the forward problem solver, which takes most of the run time (˜90 per cent in the test presented here), has been parallelized with a combination of multi-processing and message passing interface standards. This parallelization distributes the ray-tracing and traveltime calculations among available computational resources. The code's performance is illustrated with a realistic synthetic example, including a checkerboard anomaly and two reflectors, which simulates the geometry of a subduction zone. The code is designed to invert for a single reflector at a time. A data-driven layer-stripping strategy is proposed for cases involving multiple reflectors, and it is tested for the successive inversion of the two reflectors. Layers are bound by consecutive reflectors, and an initial velocity model for each inversion step incorporates the results from previous steps. This strategy poses simpler inversion problems at each step, allowing the recovery of strong velocity discontinuities that would otherwise be smoothened.

  8. Depth-based representations: Which coding format for 3D video broadcast applications?

    NASA Astrophysics Data System (ADS)

    Kerbiriou, Paul; Boisson, Guillaume; Sidibé, Korian; Huynh-Thu, Quan

    2011-03-01

    3D Video (3DV) delivery standardization is currently ongoing in MPEG. Now time is to choose 3DV data representation format. What is at stake is the final quality for end-users, i.e. synthesized views' visual quality. We focus on two major rival depth-based formats, namely Multiview Video plus Depth (MVD) and Layered Depth Video (LDV). MVD can be considered as the basic depth-based 3DV format, generated by disparity estimation from multiview sequences. LDV is more sophisticated, with the compaction of multiview data into color- and depth-occlusions layers. We compare final views quality using MVD2 and LDV (both containing two color channels plus two depth components) coded with MVC at various compression ratios. Depending on the format, the appropriate synthesis process is performed to generate final stereoscopic pairs. Comparisons are provided in terms of SSIM and PSNR with respect to original views and to synthesized references (obtained without compression). Eventually, LDV outperforms significantly MVD when using state-of-the-art reference synthesis algorithms. Occlusions management before encoding is advantageous in comparison with handling redundant signals at decoder side. Besides, we observe that depth quantization does not induce much loss on the final view quality until a significant degradation level. Improvements in disparity estimation and view synthesis algorithms are therefore still expected during the remaining standardization steps.

  9. LINFLUX-AE: A Turbomachinery Aeroelastic Code Based on a 3-D Linearized Euler Solver

    NASA Technical Reports Server (NTRS)

    Reddy, T. S. R.; Bakhle, M. A.; Trudell, J. J.; Mehmed, O.; Stefko, G. L.

    2004-01-01

    This report describes the development and validation of LINFLUX-AE, a turbomachinery aeroelastic code based on the linearized unsteady 3-D Euler solver, LINFLUX. A helical fan with flat plate geometry is selected as the test case for numerical validation. The steady solution required by LINFLUX is obtained from the nonlinear Euler/Navier Stokes solver TURBO-AE. The report briefly describes the salient features of LINFLUX and the details of the aeroelastic extension. The aeroelastic formulation is based on a modal approach. An eigenvalue formulation is used for flutter analysis. The unsteady aerodynamic forces required for flutter are obtained by running LINFLUX for each mode, interblade phase angle and frequency of interest. The unsteady aerodynamic forces for forced response analysis are obtained from LINFLUX for the prescribed excitation, interblade phase angle, and frequency. The forced response amplitude is calculated from the modal summation of the generalized displacements. The unsteady pressures, work done per cycle, eigenvalues and forced response amplitudes obtained from LINFLUX are compared with those obtained from LINSUB, TURBO-AE, ASTROP2, and ANSYS.

  10. Hyperspectral image compression: adapting SPIHT and EZW to anisotropic 3-D wavelet coding.

    PubMed

    Christophe, Emmanuel; Mailhes, Corinne; Duhamel, Pierre

    2008-12-01

    Hyperspectral images present some specific characteristics that should be used by an efficient compression system. In compression, wavelets have shown a good adaptability to a wide range of data, while being of reasonable complexity. Some wavelet-based compression algorithms have been successfully used for some hyperspectral space missions. This paper focuses on the optimization of a full wavelet compression system for hyperspectral images. Each step of the compression algorithm is studied and optimized. First, an algorithm to find the optimal 3-D wavelet decomposition in a rate-distortion sense is defined. Then, it is shown that a specific fixed decomposition has almost the same performance, while being more useful in terms of complexity issues. It is shown that this decomposition significantly improves the classical isotropic decomposition. One of the most useful properties of this fixed decomposition is that it allows the use of zero tree algorithms. Various tree structures, creating a relationship between coefficients, are compared. Two efficient compression methods based on zerotree coding (EZW and SPIHT) are adapted on this near-optimal decomposition with the best tree structure found. Performances are compared with the adaptation of JPEG 2000 for hyperspectral images on six different areas presenting different statistical properties.

  11. Implementation of wall boundary conditions for transpiration in F3D thin-layer Navier-Stokes code

    NASA Technical Reports Server (NTRS)

    Kandula, M.; Martin, F. W., Jr.

    1991-01-01

    Numerical boundary conditions for mass injection/suction at the wall are incorporated in the thin-layer Navier-Stokes code, F3D. The accuracy of the boundary conditions and the code is assessed by a detailed comparison of the predictions of velocity distributions and skin-friction coefficients with exact similarity solutions for laminar flow over a flat plate with variable blowing/suction, and measurements for turbulent flow past a flat plate with uniform blowing. In laminar flow, F3D predictions for friction coefficient compare well with exact similarity solution with and without suction, but produces large errors at moderate-to-large values of blowing. A slight Mach number dependence of skin-friction coefficient due to blowing in turbulent flow is computed by F3D code. Predicted surface pressures for turbulent flow past an airfoil with mass injection are in qualitative agreement with measurements for a flat plate.

  12. ORBXYZ: A 3D single-particle orbit code for following charged particle trajectories in equilibrium magnetic fields

    NASA Astrophysics Data System (ADS)

    Anderson, D. V.; Cohen, R. H.; Ferguson, J. R.; Johnston, B. M.; Sharp, C. B.; Willmann, P. A.

    1981-06-01

    The single particle orbit code, TIBRO, was modified extensively to improve the interpolation methods used and to allow use of vector potential fields in the simulation of charged particle orbits on a 3D domain. A 3D cubic B-spline algorithm is used to generate spline coefficients used in the interpolation. Smooth and accurate field representations are obtained. When vector potential fields are used, the 3D cubic spline interpolation formula analytically generates the magnetic field used to push the particles. This field has del.BETA = 0 to computer roundoff. When magnetic induction is used the interpolation allows del.BETA does not equal 0, which can lead to significant nonphysical results. Presently the code assumes quadrupole symmetry, but this is not an essential feature of the code and could be easily removed for other applications.

  13. An Integrated RELAP5-3D and Multiphase CFD Code System Utilizing a Semi Implicit Coupling Technique

    SciTech Connect

    D.L. Aumiller; E.T. Tomlinson; W.L. Weaver

    2001-06-21

    An integrated code system consisting of RELAP5-3D and a multiphase CFD program has been created through the use of a generic semi-implicit coupling algorithm. Unlike previous CFD coupling work, this coupling scheme is numerically stable provided the material Courant limit is not violated in RELAP5-3D or at the coupling locations. The basis for the coupling scheme and details regarding the unique features associated with the application of this technique to a four-field CFD program are presented. Finally, the results of a verification problem are presented. The coupled code system is shown to yield accurate and numerically stable results.

  14. Unequal-period combination approach of gray code and phase-shifting for 3-D visual measurement

    NASA Astrophysics Data System (ADS)

    Yu, Shuang; Zhang, Jing; Yu, Xiaoyang; Sun, Xiaoming; Wu, Haibin

    2016-09-01

    Combination of Gray code and phase-shifting is the most practical and advanced approach for the structured light 3-D measurement so far, which is able to measure objects with complex and discontinuous surface. However, for the traditional combination of the Gray code and phase-shifting, the captured Gray code images are not always sharp cut-off in the black-white conversion boundaries, which may lead to wrong decoding analog code orders. Moreover, during the actual measurement, there also exists local decoding error for the wrapped analog code obtained with the phase-shifting approach. Therefore, for the traditional approach, the wrong analog code orders and the local decoding errors will consequently introduce the errors which are equivalent to a fringe period when the analog code is unwrapped. In order to avoid one-fringe period errors, we propose an approach which combines Gray code with phase-shifting according to unequal period. With theoretical analysis, we build the measurement model of the proposed approach, determine the applicable condition and optimize the Gray code encoding period and phase-shifting fringe period. The experimental results verify that the proposed approach can offer a reliable unwrapped analog code, which can be used in 3-D shape measurement.

  15. Effect of Weaving Direction of Conductive Yarns on Electromagnetic Performance of 3D Integrated Microstrip Antenna

    NASA Astrophysics Data System (ADS)

    Xu, Fujun; Yao, Lan; Zhao, Da; Jiang, Muwen; Qiu, Yipping

    2013-10-01

    A three-dimensionally integrated microstrip antenna (3DIMA) is a microstrip antenna woven into the three-dimensional woven composite for load bearing while functioning as an antenna. In this study, the effect of weaving direction of conductive yarns on electromagnetic performance of 3DIMAs are investigated by designing, simulating and experimental testing of two microstrip antennas with different weaving directions of conductive yarns: one has the conductive yarns along the antenna feeding direction (3DIMA-Exp1) and the other has the conductive yarns perpendicular the antenna feeding direction (3DIMA-Exp2). The measured voltage standing wave ratio (VSWR) of 3DIMA-Exp1 was 1.4 at the resonant frequencies of 1.39 GHz; while that of 3DIMA-Exp2 was 1.2 at the resonant frequencies of 1.35 GHz. In addition, the measured radiation pattern of the 3DIMA-Exp1 has smaller back lobe and higher gain value than those of the 3DIMA-Exp2. This result indicates that the waving direction of conductive yarns may have a significant impact on electromagnetic performance of textile structural antennas.

  16. Electromagnetic and absorbing property of CIPs/resin composite using the 3D forming process

    NASA Astrophysics Data System (ADS)

    Xu, Yonggang; Liang, Zichang; Wang, Xiaobing; Yuan, Liming; Li, Xinghao

    2016-08-01

    The absorbing composite filled with the flaky carbonyl iron particles (CIPs) were prepared using a three-dimensional (3D) forming process, in which the forming powder was fabricated using a milling process. The surface morphology was characterized by the scanning electron microscopy, the static magnetic property was evaluated on a vibrating sample magnetometer, and X-ray diffraction (XRD) patterns were done to analyze the particle crystal grain structure. The complex permittivity and permeability were measured using a vector network analyzer in the frequency range of 4-18 GHz. With the variable thickness was set, the reflection loss (RL) was simulated to analyze the absorbing property of the composite. The results showed that the forming powder was uniformly dispersed in the absorber, and the saturation magnetization and the grain structure of the CIPs in the forming powder nearly did not change in the milling process. With the same volume content CIPs added, the average permittivity and the imaginary permeability of the samples added the powder was smaller than the directly mixing sample due to the aggregation effect. The RL results showed that the absorbing composites using the 3D forming process with thickness 6 or 8 mm had an better absorbing property (minimum RL -13.58 and -21.85 dB) in 4-18 GHz.

  17. Extension to 3-D of the low-frequency electromagnetic plasma simulation models, LDRD Final Report 95-ERD-036

    SciTech Connect

    Hewett, D.W.; DiPeso, G.; Gibbons, M; Lambert, M.; Tung, L.S.

    1997-02-03

    Low-frequency electromagnetic simulation models have a wide range of industrial applications. We have built several models, differentiated by slightly different physics approximations or computational solution methods, that have proven quite useful in a variety of applications. Our models been used to investigate beam plasma interactions in ICF targets, antenna plasma coupling in plasma processing, and magnetic implosion drive in Z-pinch pulsed power generators. The common feature of these models is that they retain inductive effects but implicitly ignore computationally intensive, fully electromagnetic effects. However, the preponderance of our work has been limited to only two dimensions. We have made significant progress modeling low-frequency electromagnetic physics with a new model in 2-D that is now capable of modeling antenna structures in 3-D. Although LLNL`s interest in plasma processing has diminished, we have certainly added to LLNL`s capabilities. Interestingly, we have already found another application, the magnetic behavior of read/write heads in the magnetic storage industry, that can make use of many of the computational methods described here, rewarding us again for maintaining a strong core competency in low-frequency EM plasmas.

  18. A new structure of 3D dual-tree discrete wavelet transforms and applications to video denoising and coding

    NASA Astrophysics Data System (ADS)

    Shi, Fei; Wang, Beibei; Selesnick, Ivan W.; Wang, Yao

    2006-01-01

    This paper introduces an anisotropic decomposition structure of a recently introduced 3-D dual-tree discrete wavelet transform (DDWT), and explores the applications for video denoising and coding. The 3-D DDWT is an attractive video representation because it isolates motion along different directions in separate subbands, and thus leads to sparse video decompositions. Our previous investigation shows that the 3-D DDWT, compared to the standard discrete wavelet transform (DWT), complies better with the statistical models based on sparse presumptions, and gives better visual and numerical results when used for statistical denoising algorithms. Our research on video compression also shows that even with 4:1 redundancy, the 3-D DDWT needs fewer coefficients to achieve the same coding quality (in PSNR) by applying the iterative projection-based noise shaping scheme proposed by Kingsbury. The proposed anisotropic DDWT extends the superiority of isotropic DDWT with more directional subbands without adding to the redundancy. Unlike the original 3-D DDWT which applies dyadic decomposition along all three directions and produces isotropic frequency spacing, it has a non-uniform tiling of the frequency space. By applying this structure, we can improve the denoising results, and the number of significant coefficients can be reduced further, which is beneficial for video coding.

  19. Development, Verification and Use of Gust Modeling in the NASA Computational Fluid Dynamics Code FUN3D

    NASA Technical Reports Server (NTRS)

    Bartels, Robert E.

    2012-01-01

    This paper presents the implementation of gust modeling capability in the CFD code FUN3D. The gust capability is verified by computing the response of an airfoil to a sharp edged gust. This result is compared with the theoretical result. The present simulations will be compared with other CFD gust simulations. This paper also serves as a users manual for FUN3D gust analyses using a variety of gust profiles. Finally, the development of an Auto-Regressive Moving-Average (ARMA) reduced order gust model using a gust with a Gaussian profile in the FUN3D code is presented. ARMA simulated results of a sequence of one-minus-cosine gusts is shown to compare well with the same gust profile computed with FUN3D. Proper Orthogonal Decomposition (POD) is combined with the ARMA modeling technique to predict the time varying pressure coefficient increment distribution due to a novel gust profile. The aeroelastic response of a pitch/plunge airfoil to a gust environment is computed with a reduced order model, and compared with a direct simulation of the system in the FUN3D code. The two results are found to agree very well.

  20. The 3-D reconstruction of medieval wetland reclamation through electromagnetic induction survey

    PubMed Central

    De Smedt, Philippe; Van Meirvenne, Marc; Herremans, Davy; De Reu, Jeroen; Saey, Timothy; Meerschman, Eef; Crombé, Philippe; De Clercq, Wim

    2013-01-01

    Studies of past human-landscape interactions rely upon the integration of archaeological, biological and geological information within their geographical context. However, detecting the often ephemeral traces of human activities at a landscape scale remains difficult with conventional archaeological field survey. Geophysical methods offer a solution by bridging the gap between point finds and the surrounding landscape, but these surveys often solely target archaeological features. Here we show how simultaneous mapping of multiple physical soil properties with a high resolution multi-receiver electromagnetic induction (EMI) survey permits a reconstruction of the three-dimensional layout and pedological setting of a medieval reclaimed landscape in Flanders (Belgium). Combined with limited and directed excavations, the results offer a unique insight into the way such marginal landscapes were reclaimed and occupied during the Middle Ages. This approach provides a robust foundation for unravelling complex historical landscapes and will enhance our understanding of past human-landscape interactions. PMID:23519060

  1. The 3-D reconstruction of medieval wetland reclamation through electromagnetic induction survey.

    PubMed

    De Smedt, Philippe; Van Meirvenne, Marc; Herremans, Davy; De Reu, Jeroen; Saey, Timothy; Meerschman, Eef; Crombé, Philippe; De Clercq, Wim

    2013-01-01

    Studies of past human-landscape interactions rely upon the integration of archaeological, biological and geological information within their geographical context. However, detecting the often ephemeral traces of human activities at a landscape scale remains difficult with conventional archaeological field survey. Geophysical methods offer a solution by bridging the gap between point finds and the surrounding landscape, but these surveys often solely target archaeological features. Here we show how simultaneous mapping of multiple physical soil properties with a high resolution multi-receiver electromagnetic induction (EMI) survey permits a reconstruction of the three-dimensional layout and pedological setting of a medieval reclaimed landscape in Flanders (Belgium). Combined with limited and directed excavations, the results offer a unique insight into the way such marginal landscapes were reclaimed and occupied during the Middle Ages. This approach provides a robust foundation for unravelling complex historical landscapes and will enhance our understanding of past human-landscape interactions.

  2. Accurate 2D/3D electromagnetic modeling for time-domain airborne EM systems

    NASA Astrophysics Data System (ADS)

    Yin, C.; Hodges, G.

    2012-12-01

    The existing industry software cannot deliver correct results for 3D time-domain airborne EM responses. In this paper, starting from the Fourier transform and convolution, we compare the stability of different modeling techniques and analyze the reason for instable calculations of the time-domain airborne EM responses. We find that the singularity of the impulse responses of EM systems at very early time that are used in the convolution is responsible for the instability of the modeling (Fig.1). Based on this finding, we put forward an algorithm that uses step response rather than impulse response of the airborne EM system for the convolution and create a stable algorithm that delivers precise results and maintains well the integral/derivative relationship between the magnetic field B and the magnetic induction dB/dt. A three-step transformation procedure for the modeling is proposed: 1) output the frequency-domain EM response data from the existing software; 2) transform into step-response by digital Fourier/Hankel transform; 3) convolve the step response with the transmitting current or its derivatives. The method has proved to be working very well (Fig. 2). The algorithm can be extended to the modeling of other time-domain ground and airborne EM system responses.Fig. 1: Comparison of impulse and step responses for an airborne EM system Fig. 2: Bz and dBz/dt calculated from step (middle panel) and impulse responses (lower panel) for the same 3D model as in Fig.1.

  3. Application of the Finite Orbit Width Version of the CQL3D Code to Transport of Fast Ions

    NASA Astrophysics Data System (ADS)

    Petrov, Yu. V.; Harvey, R. W.

    2016-10-01

    The CQL3D bounce-averaged Fokker-Planck (FP) code now includes the ``fully'' neoclassical version in which the diffusion and advection processes are averaged over actual drift orbits, rather than using a 1st-order expansion. Incorporation of Finite-Orbit-Width (FOW) effects results in neoclassical radial transport caused by collisions, RF wave heating and by toroidal electric field (radial pinch). We apply the CQL3D-full-FOW code to study the thermalization and radial transport of high-energy particles, such as alpha-particles produced by fusion in ITER or deuterons from NBI in NSTX, under effect of their interaction with auxiliary RF waves. A particular attention is given to visualization of transport in 3D space of velocity +major-radius coordinates. Supported by USDOE Grants FC02-01ER54649, FG02-04ER54744, and SC0006614.

  4. Acoustic Scattering by Three-Dimensional Stators and Rotors Using the SOURCE3D Code. Volume 2; Scattering Plots

    NASA Technical Reports Server (NTRS)

    Meyer, Harold D.

    1999-01-01

    This second volume of Acoustic Scattering by Three-Dimensional Stators and Rotors Using the SOURCE3D Code provides the scattering plots referenced by Volume 1. There are 648 plots. Half are for the 8750 rpm "high speed" operating condition and the other half are for the 7031 rpm "mid speed" operating condition.

  5. Upgrades and application of FIT3D NBI-plasma interaction code in view of LHD deuterium campaigns

    NASA Astrophysics Data System (ADS)

    Vincenzi, P.; Bolzonella, T.; Murakami, S.; Osakabe, M.; Seki, R.; Yokoyama, M.

    2016-12-01

    This work presents an upgrade of the FIT3D neutral beam-plasma interaction code, part of TASK3D, a transport suite of codes, and its application to LHD experiments in the framework of the preparation for the first deuterium experiments in the LHD. The neutral beam injector (NBI) system will be upgraded to D injection, and efforts have been recently made to extend LHD modelling capabilities to D operations. The implemented upgrades for FIT3D to enable D NBI modelling in D plasmas are presented, with a discussion and benchmark of the models used. In particular, the beam ionization module has been modified and a routine for neutron production estimation has been implemented. The upgraded code is then used to evaluate the NBI power deposition in experiments with different plasma compositions. In the recent LHD campaign, in fact, He experiments have been run to help the prediction of main effects which may be relevant in future LHD D plasmas. Identical H/He experiments showed similar electron density and temperature profiles, while a higher ion temperature with an He majority has been observed. From first applications of the upgraded FIT3D code it turns out that, although more NB power appears to be coupled with the He plasma, the NBI power deposition is unaffected, suggesting that heat deposition does not play a key role in the increased ion temperature with He plasma.

  6. Modeling and Analysis of a Lunar Space Reactor with the Computer Code RELAP5-3D/ATHENA

    SciTech Connect

    Carbajo, Juan J; Qualls, A L

    2008-01-01

    The transient analysis 3-dimensional (3-D) computer code RELAP5-3D/ATHENA has been employed to model and analyze a space reactor of 180 kW(thermal), 40 kW (net, electrical) with eight Stirling engines (SEs). Each SE will generate over 6 kWe; the excess power will be needed for the pumps and other power management devices. The reactor will be cooled by NaK (a eutectic mixture of sodium and potassium which is liquid at ambient temperature). This space reactor is intended to be deployed over the surface of the Moon or Mars. The reactor operating life will be 8 to 10 years. The RELAP5-3D/ATHENA code is being developed and maintained by Idaho National Laboratory. The code can employ a variety of coolants in addition to water, the original coolant employed with early versions of the code. The code can also use 3-D volumes and 3-D junctions, thus allowing for more realistic representation of complex geometries. A combination of 3-D and 1-D volumes is employed in this study. The space reactor model consists of a primary loop and two secondary loops connected by two heat exchangers (HXs). Each secondary loop provides heat to four SEs. The primary loop includes the nuclear reactor with the lower and upper plena, the core with 85 fuel pins, and two vertical heat exchangers (HX). The maximum coolant temperature of the primary loop is 900 K. The secondary loops also employ NaK as a coolant at a maximum temperature of 877 K. The SEs heads are at a temperature of 800 K and the cold sinks are at a temperature of ~400 K. Two radiators will be employed to remove heat from the SEs. The SE HXs surrounding the SE heads are of annular design and have been modeled using 3-D volumes. These 3-D models have been used to improve the HX design by optimizing the flows of coolant and maximizing the heat transferred to the SE heads. The transients analyzed include failure of one or more Stirling engines, trip of the reactor pump, and trips of the secondary loop pumps feeding the HXs of the

  7. Modelling of 3-D electromagnetic responses using the time-wavenumber method

    SciTech Connect

    Lee, S.

    1991-12-01

    The diffusion of electromagnetic fields in time and the three spatial dimensions can be modelled using a new numerical algorithm that is tailored for geophysical applications. The novel feature of the algorithm is that a large part of the computation is done in the wavenumber domain. Here, the spatial Fourier transforms of the vertical magnetic field and the vertical current density are used to define two scalar potentials. For either a vertical electric or a vertical magnetic dipole source at the subsurface these wavenumber potentials can be represented by a simple Gaussian distribution function. In the air, the fields satisfy the Laplace equation. The flow of this algorithm is as follows: the potentials are defined in the wavenumber domain as an initial condition depending on the source configuration, the vector current density J in space is obtained from the potentials using the inverse Fourier transform, the vector electric field E is obtained by multiplying J by resistivity, the updated potentials are then obtained from the forward Fourier transform of E. Using the updated potential as a subsequent initial condition these steps are repeated until the solution reaches the final time. Since spatial derivatives can be exactly evaluated in the wavenumber domain by simple multiplications, this algorithm requires far less memory than the conventional finite difference (FD) method. The conventional FD method needs finer discretization in space in order to minimize the numerical dispersion caused by numerical differentiation in space. The conductivity distribution for this algorithm is piece-wise continuous and bounded in the wavenumber domain.

  8. 3-D imaging of large scale buried structure by 1-D inversion of very early time electromagnetic (VETEM) data

    USGS Publications Warehouse

    Aydmer, A.A.; Chew, W.C.; Cui, T.J.; Wright, D.L.; Smith, D.V.; Abraham, J.D.

    2001-01-01

    A simple and efficient method for large scale three-dimensional (3-D) subsurface imaging of inhomogeneous background is presented. One-dimensional (1-D) multifrequency distorted Born iterative method (DBIM) is employed in the inversion. Simulation results utilizing synthetic scattering data are given. Calibration of the very early time electromagnetic (VETEM) experimental waveforms is detailed along with major problems encountered in practice and their solutions. This discussion is followed by the results of a large scale application of the method to the experimental data provided by the VETEM system of the U.S. Geological Survey. The method is shown to have a computational complexity that is promising for on-site inversion.

  9. Localization of metal targets by time reversal of electromagnetic waves . 3D-numerical and experimental study

    NASA Astrophysics Data System (ADS)

    Benhamouche, Mehdi; Bernard, Laurent; Serhir, Mohammed; Pichon, Lionel; Lesselier, Dominique

    2013-11-01

    This paper proposes a criterion for locating obstacles by time reversal (TR) of electromagnetic (EM) waves based on the analysis of the density of EM energy map in time domain. Contrarily to a monochromatic study of the TR, the wide-band approach requires to determine the instant of the wave focus. This enables us to locate the focal spots that are indicative of the positions. The criterion proposed is compared to the inverse of the minimum entropy criterion as used in the literature [X. Xu, E.L. Miller, C.M. Rappaport, IEEE Trans. Geosci. Remote Sens. 41, 1804 (2003)]. An application for the localization of 3D metal targets is proposed using finite integration technique (FIT) as computational tool at the modeling stage. An experimental validation is presented for canonical three-dimensional configurations with two kinds of metal objects. Contribution to the Topical Issue "Numelec 2012", Edited by Adel Razek.

  10. ADVANCED ELECTRIC AND MAGNETIC MATERIAL MODELS FOR FDTD ELECTROMAGNETIC CODES

    SciTech Connect

    Poole, B R; Nelson, S D; Langdon, S

    2005-05-05

    The modeling of dielectric and magnetic materials in the time domain is required for pulse power applications, pulsed induction accelerators, and advanced transmission lines. For example, most induction accelerator modules require the use of magnetic materials to provide adequate Volt-sec during the acceleration pulse. These models require hysteresis and saturation to simulate the saturation wavefront in a multipulse environment. In high voltage transmission line applications such as shock or soliton lines the dielectric is operating in a highly nonlinear regime, which require nonlinear models. Simple 1-D models are developed for fast parameterization of transmission line structures. In the case of nonlinear dielectrics, a simple analytic model describing the permittivity in terms of electric field is used in a 3-D finite difference time domain code (FDTD). In the case of magnetic materials, both rate independent and rate dependent Hodgdon magnetic material models have been implemented into 3-D FDTD codes and 1-D codes.

  11. Inversion of multi-frequency electromagnetic induction data for 3D characterization of hydraulic conductivity

    USGS Publications Warehouse

    Brosten, T.R.; Day-Lewis, F. D.; Schultz, G.M.; Curtis, G.P.; Lane, J.W.

    2011-01-01

    Electromagnetic induction (EMI) instruments provide rapid, noninvasive, and spatially dense data for characterization of soil and groundwater properties. Data from multi-frequency EMI tools can be inverted to provide quantitative electrical conductivity estimates as a function of depth. In this study, multi-frequency EMI data collected across an abandoned uranium mill site near Naturita, Colorado, USA, are inverted to produce vertical distribution of electrical conductivity (EC) across the site. The relation between measured apparent electrical conductivity (ECa) and hydraulic conductivity (K) is weak (correlation coefficient of 0.20), whereas the correlation between the depth dependent EC obtained from the inversions, and K is sufficiently strong to be used for hydrologic estimation (correlation coefficient of -0.62). Depth-specific EC values were correlated with co-located K measurements to develop a site-specific ln(EC)-ln(K) relation. This petrophysical relation was applied to produce a spatially detailed map of K across the study area. A synthetic example based on ECa values at the site was used to assess model resolution and correlation loss given variations in depth and/or measurement error. Results from synthetic modeling indicate that optimum correlation with K occurs at ~0.5m followed by a gradual correlation loss of 90% at 2.3m. These results are consistent with an analysis of depth of investigation (DOI) given the range of frequencies, transmitter-receiver separation, and measurement errors for the field data. DOIs were estimated at 2.0??0.5m depending on the soil conductivities. A 4-layer model, with varying thicknesses, was used to invert the ECa to maximize available information within the aquifer region for improved correlations with K. Results show improved correlation between K and the corresponding inverted EC at similar depths, underscoring the importance of inversion in using multi-frequency EMI data for hydrologic estimation. ?? 2011.

  12. 3D transient electromagnetic simulation using a modified correspondence principle for wave and diffusion fields

    NASA Astrophysics Data System (ADS)

    Hu, Y.; Ji, Y.; Egbert, G. D.

    2015-12-01

    The fictitious time domain method (FTD), based on the correspondence principle for wave and diffusion fields, has been developed and used over the past few years primarily for marine electromagnetic (EM) modeling. Here we present results of our efforts to apply the FTD approach to land and airborne TEM problems which can reduce the computer time several orders of magnitude and preserve high accuracy. In contrast to the marine case, where sources are in the conductive sea water, we must model the EM fields in the air; to allow for topography air layers must be explicitly included in the computational domain. Furthermore, because sources for most TEM applications generally must be modeled as finite loops, it is useful to solve directly for the impulse response appropriate to the problem geometry, instead of the point-source Green functions typically used for marine problems. Our approach can be summarized as follows: (1) The EM diffusion equation is transformed to a fictitious wave equation. (2) The FTD wave equation is solved with an explicit finite difference time-stepping scheme, with CPML (Convolutional PML) boundary conditions for the whole computational domain including the air and earth , with FTD domain source corresponding to the actual transmitter geometry. Resistivity of the air layers is kept as low as possible, to compromise between efficiency (longer fictitious time step) and accuracy. We have generally found a host/air resistivity contrast of 10-3 is sufficient. (3)A "Modified" Fourier Transform (MFT) allow us recover system's impulse response from the fictitious time domain to the diffusion (frequency) domain. (4) The result is multiplied by the Fourier transformation (FT) of the real source current avoiding time consuming convolutions in the time domain. (5) The inverse FT is employed to get the final full waveform and full time response of the system in the time domain. In general, this method can be used to efficiently solve most time-domain EM

  13. Validation of the BISON 3D Fuel Performance Code: Temperature Comparisons for Concentrically and Eccentrically Located Fuel Pellets

    SciTech Connect

    J. D. Hales; D. M. Perez; R. L. Williamson; S. R. Novascone; B. W. Spencer

    2013-03-01

    BISON is a modern finite-element based nuclear fuel performance code that has been under development at the Idaho National Laboratory (USA) since 2009. The code is applicable to both steady and transient fuel behaviour and is used to analyse either 2D axisymmetric or 3D geometries. BISON has been applied to a variety of fuel forms including LWR fuel rods, TRISO-coated fuel particles, and metallic fuel in both rod and plate geometries. Code validation is currently in progress, principally by comparison to instrumented LWR fuel rods. Halden IFA experiments constitute a large percentage of the current BISON validation base. The validation emphasis here is centreline temperatures at the beginning of fuel life, with comparisons made to seven rods from the IFA-431 and 432 assemblies. The principal focus is IFA-431 Rod 4, which included concentric and eccentrically located fuel pellets. This experiment provides an opportunity to explore 3D thermomechanical behaviour and assess the 3D simulation capabilities of BISON. Analysis results agree with experimental results showing lower fuel centreline temperatures for eccentric fuel with the peak temperature shifted from the centreline. The comparison confirms with modern 3D analysis tools that the measured temperature difference between concentric and eccentric pellets is not an artefact and provides a quantitative explanation for the difference.

  14. The Numerical Electromagnetics Code (NEC) - A Brief History

    SciTech Connect

    Burke, G J; Miller, E K; Poggio, A J

    2004-01-20

    The Numerical Electromagnetics Code, NEC as it is commonly known, continues to be one of the more widely used antenna modeling codes in existence. With several versions in use that reflect different levels of capability and availability, there are now 450 copies of NEC4 and 250 copies of NEC3 that have been distributed by Lawrence Livermore National Laboratory to a limited class of qualified recipients, and several hundred copies of NEC2 that had a recorded distribution by LLNL. These numbers do not account for numerous copies (perhaps 1000s) that were acquired through other means capitalizing on the open source code, the absence of distribution controls prior to NEC3 and the availability of versions on the Internet. In this paper we briefly review the history of the code that is concisely displayed in Figure 1. We will show how it capitalized on the research of prominent contributors in the early days of computational electromagnetics, how a combination of events led to the tri-service-supported code development program that ultimately led to NEC and how it evolved to the present day product. The authors apologize that space limitations do not allow us to provide a list of references or to acknowledge the numerous contributors to the code both of which can be found in the code documents.

  15. User's manual for three dimensional boundary layer (BL3-D) code

    NASA Technical Reports Server (NTRS)

    Anderson, O. L.; Caplin, B.

    1985-01-01

    An assessment has been made of the applicability of a 3-D boundary layer analysis to the calculation of heat transfer, total pressure losses, and streamline flow patterns on the surface of both stationary and rotating turbine passages. In support of this effort, an analysis has been developed to calculate a general nonorthogonal surface coordinate system for arbitrary 3-D surfaces and also to calculate the boundary layer edge conditions for compressible flow using the surface Euler equations and experimental data to calibrate the method, calculations are presented for the pressure endwall, and suction surfaces of a stationary cascade and for the pressure surface of a rotating turbine blade. The results strongly indicate that the 3-D boundary layer analysis can give good predictions of the flow field, loss, and heat transfer on the pressure, suction, and endwall surface of a gas turbine passage.

  16. User's manual for three dimensional boundary layer (BL3-D) code

    NASA Astrophysics Data System (ADS)

    Anderson, O. L.; Caplin, B.

    1985-08-01

    An assessment has been made of the applicability of a 3-D boundary layer analysis to the calculation of heat transfer, total pressure losses, and streamline flow patterns on the surface of both stationary and rotating turbine passages. In support of this effort, an analysis has been developed to calculate a general nonorthogonal surface coordinate system for arbitrary 3-D surfaces and also to calculate the boundary layer edge conditions for compressible flow using the surface Euler equations and experimental data to calibrate the method, calculations are presented for the pressure endwall, and suction surfaces of a stationary cascade and for the pressure surface of a rotating turbine blade. The results strongly indicate that the 3-D boundary layer analysis can give good predictions of the flow field, loss, and heat transfer on the pressure, suction, and endwall surface of a gas turbine passage.

  17. TART97 a coupled neutron-photon 3-D, combinatorial geometry Monte Carlo transport code

    SciTech Connect

    Cullen, D.E.

    1997-11-22

    TART97 is a coupled neutron-photon, 3 Dimensional, combinatorial geometry, time dependent Monte Carlo transport code. This code can on any modern computer. It is a complete system to assist you with input preparation, running Monte Carlo calculations, and analysis of output results. TART97 is also incredibly FAST; if you have used similar codes, you will be amazed at how fast this code is compared to other similar codes. Use of the entire system can save you a great deal of time and energy. TART97 is distributed on CD. This CD contains on- line documentation for all codes included in the system, the codes configured to run on a variety of computers, and many example problems that you can use to familiarize yourself with the system. TART97 completely supersedes all older versions of TART, and it is strongly recommended that users only use the most recent version of TART97 and its data riles.

  18. Massive parallelization of a 3D finite difference electromagnetic forward solution using domain decomposition methods on multiple CUDA enabled GPUs

    NASA Astrophysics Data System (ADS)

    Schultz, A.

    2010-12-01

    3D forward solvers lie at the core of inverse formulations used to image the variation of electrical conductivity within the Earth's interior. This property is associated with variations in temperature, composition, phase, presence of volatiles, and in specific settings, the presence of groundwater, geothermal resources, oil/gas or minerals. The high cost of 3D solutions has been a stumbling block to wider adoption of 3D methods. Parallel algorithms for modeling frequency domain 3D EM problems have not achieved wide scale adoption, with emphasis on fairly coarse grained parallelism using MPI and similar approaches. The communications bandwidth as well as the latency required to send and receive network communication packets is a limiting factor in implementing fine grained parallel strategies, inhibiting wide adoption of these algorithms. Leading Graphics Processor Unit (GPU) companies now produce GPUs with hundreds of GPU processor cores per die. The footprint, in silicon, of the GPU's restricted instruction set is much smaller than the general purpose instruction set required of a CPU. Consequently, the density of processor cores on a GPU can be much greater than on a CPU. GPUs also have local memory, registers and high speed communication with host CPUs, usually through PCIe type interconnects. The extremely low cost and high computational power of GPUs provides the EM geophysics community with an opportunity to achieve fine grained (i.e. massive) parallelization of codes on low cost hardware. The current generation of GPUs (e.g. NVidia Fermi) provides 3 billion transistors per chip die, with nearly 500 processor cores and up to 6 GB of fast (DDR5) GPU memory. This latest generation of GPU supports fast hardware double precision (64 bit) floating point operations of the type required for frequency domain EM forward solutions. Each Fermi GPU board can sustain nearly 1 TFLOP in double precision, and multiple boards can be installed in the host computer system. We

  19. The digital code driven autonomous synthesis of ibuprofen automated in a 3D-printer-based robot.

    PubMed

    Kitson, Philip J; Glatzel, Stefan; Cronin, Leroy

    2016-01-01

    An automated synthesis robot was constructed by modifying an open source 3D printing platform. The resulting automated system was used to 3D print reaction vessels (reactionware) of differing internal volumes using polypropylene feedstock via a fused deposition modeling 3D printing approach and subsequently make use of these fabricated vessels to synthesize the nonsteroidal anti-inflammatory drug ibuprofen via a consecutive one-pot three-step approach. The synthesis of ibuprofen could be achieved on different scales simply by adjusting the parameters in the robot control software. The software for controlling the synthesis robot was written in the python programming language and hard-coded for the synthesis of ibuprofen by the method described, opening possibilities for the sharing of validated synthetic 'programs' which can run on similar low cost, user-constructed robotic platforms towards an 'open-source' regime in the area of chemical synthesis.

  20. The digital code driven autonomous synthesis of ibuprofen automated in a 3D-printer-based robot

    PubMed Central

    Kitson, Philip J; Glatzel, Stefan

    2016-01-01

    An automated synthesis robot was constructed by modifying an open source 3D printing platform. The resulting automated system was used to 3D print reaction vessels (reactionware) of differing internal volumes using polypropylene feedstock via a fused deposition modeling 3D printing approach and subsequently make use of these fabricated vessels to synthesize the nonsteroidal anti-inflammatory drug ibuprofen via a consecutive one-pot three-step approach. The synthesis of ibuprofen could be achieved on different scales simply by adjusting the parameters in the robot control software. The software for controlling the synthesis robot was written in the python programming language and hard-coded for the synthesis of ibuprofen by the method described, opening possibilities for the sharing of validated synthetic ‘programs’ which can run on similar low cost, user-constructed robotic platforms towards an ‘open-source’ regime in the area of chemical synthesis. PMID:28144350

  1. Recent Hydrodynamics Improvements to the RELAP5-3D Code

    SciTech Connect

    Richard A. Riemke; Cliff B. Davis; Richard.R. Schultz

    2009-07-01

    The hydrodynamics section of the RELAP5-3D computer program has been recently improved. Changes were made as follows: (1) improved turbine model, (2) spray model for the pressurizer model, (3) feedwater heater model, (4) radiological transport model, (5) improved pump model, and (6) compressor model.

  2. Simulations of 3D LPI's relevant to IFE using the PIC code OSIRIS

    NASA Astrophysics Data System (ADS)

    Tsung, F. S.; Mori, W. B.; Winjum, B. J.

    2014-10-01

    We will study three dimensional effects of laser plasma instabilities, including backward raman scattering, the high frequency hybrid instability, and the two plasmon instability using OSIRIS in 3D Cartesian geometry and cylindrical 2D OSIRIS with azimuthal mode decompositions. With our new capabilities we hope to demonstrate that we are capable of studying single speckle physics relevant to IFE in an efficent manner.

  3. Preliminary Results from the Application of Automated Adjoint Code Generation to CFL3D

    NASA Technical Reports Server (NTRS)

    Carle, Alan; Fagan, Mike; Green, Lawrence L.

    1998-01-01

    This report describes preliminary results obtained using an automated adjoint code generator for Fortran to augment a widely-used computational fluid dynamics flow solver to compute derivatives. These preliminary results with this augmented code suggest that, even in its infancy, the automated adjoint code generator can accurately and efficiently deliver derivatives for use in transonic Euler-based aerodynamic shape optimization problems with hundreds to thousands of independent design variables.

  4. Assessment of 3D Codes for Predicting Liner Attenuation in Flow Ducts

    NASA Technical Reports Server (NTRS)

    Watson, W. R.; Nark, D. M.; Jones, M. G.

    2008-01-01

    This paper presents comparisons of seven propagation codes for predicting liner attenuation in ducts with flow. The selected codes span the spectrum of methods available (finite element, parabolic approximation, and pseudo-time domain) and are collectively representative of the state-of-art in the liner industry. These codes are included because they have two-dimensional and three-dimensional versions and can be exported to NASA's Columbia Supercomputer. The basic assumptions, governing differential equations, boundary conditions, and numerical methods underlying each code are briefly reviewed and an assessment is performed based on two predefined metrics. The two metrics used in the assessment are the accuracy of the predicted attenuation and the amount of wall clock time to predict the attenuation. The assessment is performed over a range of frequencies, mean flow rates, and grazing flow liner impedances commonly used in the liner industry. The primary conclusions of the study are (1) predicted attenuations are in good agreement for rigid wall ducts, (2) the majority of codes compare well to each other and to approximate results from mode theory for soft wall ducts, (3) most codes compare well to measured data on a statistical basis, (4) only the finite element codes with cubic Hermite polynomials capture extremely large attenuations, and (5) wall clock time increases by an order of magnitude or more are observed for a three-dimensional code relative to the corresponding two-dimensional version of the same code.

  5. iRegNet3D: three-dimensional integrated regulatory network for the genomic analysis of coding and non-coding disease mutations.

    PubMed

    Liang, Siqi; Tippens, Nathaniel D; Zhou, Yaoda; Mort, Matthew; Stenson, Peter D; Cooper, David N; Yu, Haiyuan

    2017-01-18

    The mechanistic details of most disease-causing mutations remain poorly explored within the context of regulatory networks. We present a high-resolution three-dimensional integrated regulatory network (iRegNet3D) in the form of a web tool, where we resolve the interfaces of all known transcription factor (TF)-TF, TF-DNA and chromatin-chromatin interactions for the analysis of both coding and non-coding disease-associated mutations to obtain mechanistic insights into their functional impact. Using iRegNet3D, we find that disease-associated mutations may perturb the regulatory network through diverse mechanisms including chromatin looping. iRegNet3D promises to be an indispensable tool in large-scale sequencing and disease association studies.

  6. 3D Simulation of Elastic Wave Propagation in Heterogeneous Anisotropic Media in Laplace Domain for Electromagnetic-Seismic Inverse Modeling

    NASA Astrophysics Data System (ADS)

    Petrov, P.; Newman, G. A.

    2011-12-01

    Recent developments in high resolution imaging technology of subsurface objects involves a combination of different geophysical measurements (gravity, EM and seismic). A joint image of the subsurface geophysical attributes (velocity, electrical conductivity and density) requires the consistent treatment of the different geophysical data due to their differing physical nature. For example, in conducting media, which is typical of the Earth's interior, EM energy propagation is defined by a diffusive mechanism and may be characterized by two specific length scales: wavelength and skin depth. However, the propagation of seismic signals is a multiwave process and is characterized by a set of wavelengths. Thus, to consistently treat seismic and electromagnetic data an additional length scale is needed for seismic data that does not directly depend on a wavelength and describes a diffusive process, similar to EM wave propagation in the subsurface. Works by Brown et al.(2005), Shin and Cha(2008), and Shin and Ha(2008) suggest that an artificial damping of seismic wave fields via Laplace-Fourier transformation can be an effective approach to obtain a seismic data that have similar spatial resolution to EM data. The key benefit of such transformation is that diffusive wave-field inversion works well for both data sets: seismic (Brown et al.,2005; Shin and Cha,2008) and electromagnetic (Commer and Newman,2008; Newman et al.,2010). With the recent interest in the Laplace-Fourier domain full waveform inversion, 3D fourth and second-order finite-difference schemes for modeling of seismic wave propagation have been developed (Petrov and Newman, 2010). Incorporation of attenuation and anisotropy into a velocity model is a necessary step for a more realistic description of subsurface media. Here we consider the extension of our method which includes attenuation and VTI anisotropy. Our approach is based on the integro-interpolation technique for velocity-stress formulation. Seven

  7. Implementation of a 3D halo neutral model in the TRANSP code and application to projected NSTX-U plasmas

    SciTech Connect

    Medley, S. S.; Liu, D.; Gorelenkova, M. V.; Heidbrink, W. W.; Stagner, L.

    2016-01-12

    A 3D halo neutral code developed at the Princeton Plasma Physics Laboratory and implemented for analysis using the TRANSP code is applied to projected National Spherical Torus eXperiment-Upgrade (NSTX-U plasmas). The legacy TRANSP code did not handle halo neutrals properly since they were distributed over the plasma volume rather than remaining in the vicinity of the neutral beam footprint as is actually the case. The 3D halo neutral code uses a 'beam-in-a-box' model that encompasses both injected beam neutrals and resulting halo neutrals. Upon deposition by charge exchange, a subset of the full, one-half and one-third beam energy components produce first generation halo neutrals that are tracked through successive generations until an ionization event occurs or the descendant halos exit the box. The 3D halo neutral model and neutral particle analyzer (NPA) simulator in the TRANSP code have been benchmarked with the Fast-Ion D-Alpha simulation (FIDAsim) code, which provides Monte Carlo simulations of beam neutral injection, attenuation, halo generation, halo spatial diffusion, and photoemission processes. When using the same atomic physics database, TRANSP and FIDAsim simulations achieve excellent agreement on the spatial profile and magnitude of beam and halo neutral densities and the NPA energy spectrum. The simulations show that the halo neutral density can be comparable to the beam neutral density. These halo neutrals can double the NPA flux, but they have minor effects on the NPA energy spectrum shape. The TRANSP and FIDAsim simulations also suggest that the magnitudes of beam and halo neutral densities are relatively sensitive to the choice of the atomic physics databases.

  8. Implementation of a 3D halo neutral model in the TRANSP code and application to projected NSTX-U plasmas

    NASA Astrophysics Data System (ADS)

    Medley, S. S.; Liu, D.; Gorelenkova, M. V.; Heidbrink, W. W.; Stagner, L.

    2016-02-01

    A 3D halo neutral code developed at the Princeton Plasma Physics Laboratory and implemented for analysis using the TRANSP code is applied to projected National Spherical Torus eXperiment-Upgrade (NSTX-U plasmas). The legacy TRANSP code did not handle halo neutrals properly since they were distributed over the plasma volume rather than remaining in the vicinity of the neutral beam footprint as is actually the case. The 3D halo neutral code uses a ‘beam-in-a-box’ model that encompasses both injected beam neutrals and resulting halo neutrals. Upon deposition by charge exchange, a subset of the full, one-half and one-third beam energy components produce first generation halo neutrals that are tracked through successive generations until an ionization event occurs or the descendant halos exit the box. The 3D halo neutral model and neutral particle analyzer (NPA) simulator in the TRANSP code have been benchmarked with the Fast-Ion D-Alpha simulation (FIDAsim) code, which provides Monte Carlo simulations of beam neutral injection, attenuation, halo generation, halo spatial diffusion, and photoemission processes. When using the same atomic physics database, TRANSP and FIDAsim simulations achieve excellent agreement on the spatial profile and magnitude of beam and halo neutral densities and the NPA energy spectrum. The simulations show that the halo neutral density can be comparable to the beam neutral density. These halo neutrals can double the NPA flux, but they have minor effects on the NPA energy spectrum shape. The TRANSP and FIDAsim simulations also suggest that the magnitudes of beam and halo neutral densities are relatively sensitive to the choice of the atomic physics databases.

  9. 3D Electromagnetic Particle-in-Cell simulations of the solar wind interaction with lunar magnetic anomalies

    NASA Astrophysics Data System (ADS)

    Deca, J.; Lapenta, G.; Divin, A. V.; Lembege, B.; Markidis, S.

    2013-12-01

    Unlike the Earth and Mercury, our Moon has no global magnetic field and is therefore not shielded from the impinging solar wind by a magnetosphere. However, lunar magnetic field measurements made by the Apollo missions provided direct evidence that the Moon has regions of small-scale crustal magnetic fields, ranging up to a few 100km in scale size with surface magnetic field strengths up to hundreds of nanoTeslas. More recently, the Lunar Prospector spacecraft has provided high-resolution observations allowing to construct magnetic field maps of the entire Moon, confirming the earlier results from Apollo, but also showing that the lunar plasma environment is much richer than earlier believed. Typically the small-scale magnetic fields are non-dipolar and rather tiny compared to the lunar radius and mainly clustered on the far side of the moon. Using iPic3D we present the first 3D fully kinetic and electromagnetic Particle-in-Cell simulations of the solar wind interaction with lunar magnetic anomalies. We study the behaviour of a dipole model with variable surface magnetic field strength under changing solar wind conditions and confirm that lunar crustal magnetic fields may indeed be strong enough to stand off the solar wind and form a mini-magnetosphere, as suggested by MHD and hybrid simulations and spacecraft observations. 3D-PIC simulations reveal to be very helpful to analyze the diversion/braking of the particle flux and the characteristics of the resulting particles accumulation. The particle flux to the surface is significantly reduced at the magnetic anomaly, surrounded by a region of enhanced density due to the magnetic mirror effect. Second, the ability of iPic3D to resolve all plasma components (heavy ions, protons and electrons) allows to discuss in detail the electron physics leading to the highly non-adiabatic interactions expected as well as the implications for solar wind shielding of the lunar surface, depending on the scale size (solar wind protons

  10. Analysis and Compensation for Lateral Chromatic Aberration in a Color Coding Structured Light 3D Measurement System

    PubMed Central

    Huang, Junhui; Xue, Qi; Wang, Zhao; Gao, Jianmin

    2016-01-01

    While color-coding methods have improved the measuring efficiency of a structured light three-dimensional (3D) measurement system, they decreased the measuring accuracy significantly due to lateral chromatic aberration (LCA). In this study, the LCA in a structured light measurement system is analyzed, and a method is proposed to compensate the error caused by the LCA. Firstly, based on the projective transformation, a 3D error map of LCA is constructed in the projector images by using a flat board and comparing the image coordinates of red, green and blue circles with the coordinates of white circles at preselected sample points within the measurement volume. The 3D map consists of the errors, which are the equivalent errors caused by LCA of the camera and projector. Then in measurements, error values of LCA are calculated and compensated to correct the projector image coordinates through the 3D error map and a tri-linear interpolation method. Eventually, 3D coordinates with higher accuracy are re-calculated according to the compensated image coordinates. The effectiveness of the proposed method is verified in the following experiments. PMID:27598174

  11. Analysis and Compensation for Lateral Chromatic Aberration in a Color Coding Structured Light 3D Measurement System.

    PubMed

    Huang, Junhui; Xue, Qi; Wang, Zhao; Gao, Jianmin

    2016-09-03

    While color-coding methods have improved the measuring efficiency of a structured light three-dimensional (3D) measurement system, they decreased the measuring accuracy significantly due to lateral chromatic aberration (LCA). In this study, the LCA in a structured light measurement system is analyzed, and a method is proposed to compensate the error caused by the LCA. Firstly, based on the projective transformation, a 3D error map of LCA is constructed in the projector images by using a flat board and comparing the image coordinates of red, green and blue circles with the coordinates of white circles at preselected sample points within the measurement volume. The 3D map consists of the errors, which are the equivalent errors caused by LCA of the camera and projector. Then in measurements, error values of LCA are calculated and compensated to correct the projector image coordinates through the 3D error map and a tri-linear interpolation method. Eventually, 3D coordinates with higher accuracy are re-calculated according to the compensated image coordinates. The effectiveness of the proposed method is verified in the following experiments.

  12. Full 3D visualization tool-kit for Monte Carlo and deterministic transport codes

    SciTech Connect

    Frambati, S.; Frignani, M.

    2012-07-01

    We propose a package of tools capable of translating the geometric inputs and outputs of many Monte Carlo and deterministic radiation transport codes into open source file formats. These tools are aimed at bridging the gap between trusted, widely-used radiation analysis codes and very powerful, more recent and commonly used visualization software, thus supporting the design process and helping with shielding optimization. Three main lines of development were followed: mesh-based analysis of Monte Carlo codes, mesh-based analysis of deterministic codes and Monte Carlo surface meshing. The developed kit is considered a powerful and cost-effective tool in the computer-aided design for radiation transport code users of the nuclear world, and in particular in the fields of core design and radiation analysis. (authors)

  13. Numerical Simulation of Two-grid Ion Optics Using a 3D Code

    NASA Technical Reports Server (NTRS)

    Anderson, John R.; Katz, Ira; Goebel, Dan

    2004-01-01

    A three-dimensional ion optics code has been developed under NASA's Project Prometheus to model two grid ion optics systems. The code computes the flow of positive ions from the discharge chamber through the ion optics and into the beam downstream of the thruster. The rate at which beam ions interact with background neutral gas to form charge exchange ions is also computed. Charge exchange ion trajectories are computed to determine where they strike the ion optics grid surfaces and to determine the extent of sputter erosion they cause. The code has been used to compute predictions of the erosion pattern and wear rate on the NSTAR ion optics system; the code predicts the shape of the eroded pattern but overestimates the initial wear rate by about 50%. An example of use of the code to estimate the NEXIS thruster accelerator grid life is also presented.

  14. Development of a 3-D upwind PNS code for chemically reacting hypersonic flowfields

    NASA Technical Reports Server (NTRS)

    Tannehill, J. C.; Wadawadigi, G.

    1992-01-01

    Two new parabolized Navier-Stokes (PNS) codes were developed to compute the three-dimensional, viscous, chemically reacting flow of air around hypersonic vehicles such as the National Aero-Space Plane (NASP). The first code (TONIC) solves the gas dynamic and species conservation equations in a fully coupled manner using an implicit, approximately-factored, central-difference algorithm. This code was upgraded to include shock fitting and the capability of computing the flow around complex body shapes. The revised TONIC code was validated by computing the chemically-reacting (M(sub infinity) = 25.3) flow around a 10 deg half-angle cone at various angles of attack and the Ames All-Body model at 0 deg angle of attack. The results of these calculations were in good agreement with the results from the UPS code. One of the major drawbacks of the TONIC code is that the central-differencing of fluxes across interior flowfield discontinuities tends to introduce errors into the solution in the form of local flow property oscillations. The second code (UPS), originally developed for a perfect gas, has been extended to permit either perfect gas, equilibrium air, or nonequilibrium air computations. The code solves the PNS equations using a finite-volume, upwind TVD method based on Roe's approximate Riemann solver that was modified to account for real gas effects. The dissipation term associated with this algorithm is sufficiently adaptive to flow conditions that, even when attempting to capture very strong shock waves, no additional smoothing is required. For nonequilibrium calculations, the code solves the fluid dynamic and species continuity equations in a loosely-coupled manner. This code was used to calculate the hypersonic, laminar flow of chemically reacting air over cones at various angles of attack. In addition, the flow around the McDonnel Douglas generic option blended-wing-body was computed and comparisons were made between the perfect gas, equilibrium air, and the

  15. Advances in Parallel Electromagnetic Codes for Accelerator Science and Development

    SciTech Connect

    Ko, Kwok; Candel, Arno; Ge, Lixin; Kabel, Andreas; Lee, Rich; Li, Zenghai; Ng, Cho; Rawat, Vineet; Schussman, Greg; Xiao, Liling; /SLAC

    2011-02-07

    Over a decade of concerted effort in code development for accelerator applications has resulted in a new set of electromagnetic codes which are based on higher-order finite elements for superior geometry fidelity and better solution accuracy. SLAC's ACE3P code suite is designed to harness the power of massively parallel computers to tackle large complex problems with the increased memory and solve them at greater speed. The US DOE supports the computational science R&D under the SciDAC project to improve the scalability of ACE3P, and provides the high performance computing resources needed for the applications. This paper summarizes the advances in the ACE3P set of codes, explains the capabilities of the modules, and presents results from selected applications covering a range of problems in accelerator science and development important to the Office of Science.

  16. A 3D-CFD code for accurate prediction of fluid flows and fluid forces in seals

    NASA Technical Reports Server (NTRS)

    Athavale, M. M.; Przekwas, A. J.; Hendricks, R. C.

    1994-01-01

    Current and future turbomachinery requires advanced seal configurations to control leakage, inhibit mixing of incompatible fluids and to control the rotodynamic response. In recognition of a deficiency in the existing predictive methodology for seals, a seven year effort was established in 1990 by NASA's Office of Aeronautics Exploration and Technology, under the Earth-to-Orbit Propulsion program, to develop validated Computational Fluid Dynamics (CFD) concepts, codes and analyses for seals. The effort will provide NASA and the U.S. Aerospace Industry with advanced CFD scientific codes and industrial codes for analyzing and designing turbomachinery seals. An advanced 3D CFD cylindrical seal code has been developed, incorporating state-of-the-art computational methodology for flow analysis in straight, tapered and stepped seals. Relevant computational features of the code include: stationary/rotating coordinates, cylindrical and general Body Fitted Coordinates (BFC) systems, high order differencing schemes, colocated variable arrangement, advanced turbulence models, incompressible/compressible flows, and moving grids. This paper presents the current status of code development, code demonstration for predicting rotordynamic coefficients, numerical parametric study of entrance loss coefficients for generic annular seals, and plans for code extensions to labyrinth, damping, and other seal configurations.

  17. Load-balancing techniques for a parallel electromagnetic particle-in-cell code

    SciTech Connect

    PLIMPTON,STEVEN J.; SEIDEL,DAVID B.; PASIK,MICHAEL F.; COATS,REBECCA S.

    2000-01-01

    QUICKSILVER is a 3-d electromagnetic particle-in-cell simulation code developed and used at Sandia to model relativistic charged particle transport. It models the time-response of electromagnetic fields and low-density-plasmas in a self-consistent manner: the fields push the plasma particles and the plasma current modifies the fields. Through an LDRD project a new parallel version of QUICKSILVER was created to enable large-scale plasma simulations to be run on massively-parallel distributed-memory supercomputers with thousands of processors, such as the Intel Tflops and DEC CPlant machines at Sandia. The new parallel code implements nearly all the features of the original serial QUICKSILVER and can be run on any platform which supports the message-passing interface (MPI) standard as well as on single-processor workstations. This report describes basic strategies useful for parallelizing and load-balancing particle-in-cell codes, outlines the parallel algorithms used in this implementation, and provides a summary of the modifications made to QUICKSILVER. It also highlights a series of benchmark simulations which have been run with the new code that illustrate its performance and parallel efficiency. These calculations have up to a billion grid cells and particles and were run on thousands of processors. This report also serves as a user manual for people wishing to run parallel QUICKSILVER.

  18. Development of a Top-View Numeric Coding Teaching-Learning Trajectory within an Elementary Grades 3-D Visualization Design Research Project

    ERIC Educational Resources Information Center

    Sack, Jacqueline J.

    2013-01-01

    This article explicates the development of top-view numeric coding of 3-D cube structures within a design research project focused on 3-D visualization skills for elementary grades children. It describes children's conceptual development of 3-D cube structures using concrete models, conventional 2-D pictures and abstract top-view numeric…

  19. Users manual for CAFE-3D : a computational fluid dynamics fire code.

    SciTech Connect

    Khalil, Imane; Lopez, Carlos; Suo-Anttila, Ahti Jorma

    2005-03-01

    The Container Analysis Fire Environment (CAFE) computer code has been developed to model all relevant fire physics for predicting the thermal response of massive objects engulfed in large fires. It provides realistic fire thermal boundary conditions for use in design of radioactive material packages and in risk-based transportation studies. The CAFE code can be coupled to commercial finite-element codes such as MSC PATRAN/THERMAL and ANSYS. This coupled system of codes can be used to determine the internal thermal response of finite element models of packages to a range of fire environments. This document is a user manual describing how to use the three-dimensional version of CAFE, as well as a description of CAFE input and output parameters. Since this is a user manual, only a brief theoretical description of the equations and physical models is included.

  20. SPACE CHARGE DYNAMICS SIMULATED IN 3 - D IN THE CODE ORBIT.

    SciTech Connect

    LUCCIO,A.U.; DIMPERIO,N.L.; BEEBE - WANG,J.

    2002-06-02

    Several improvements have been done on space charge calculations in the PIC code ORBIT, specialized for high intensity circular hadron accelerators. We present results of different Poisson solvers in the presence of conductive walls.

  1. Version 3.0 of code Java for 3D simulation of the CCA model

    NASA Astrophysics Data System (ADS)

    Zhang, Kebo; Zuo, Junsen; Dou, Yifeng; Li, Chao; Xiong, Hailing

    2016-10-01

    In this paper we provide a new version of program for replacing the previous version. The frequency of traversing the clusters-list was reduced, and some code blocks were optimized properly; in addition, we appended and revised the comments of the source code for some methods or attributes. The compared experimental results show that new version has better time efficiency than the previous version.

  2. Kinetic approach to the formation of 3D electromagnetic structures in flows of expanding plasma coronas. II. flow anisotropy parameters

    NASA Astrophysics Data System (ADS)

    Gubchenko, V. M.

    2015-12-01

    The formation of magnetic structures in moving hot solar coronal plasma and hot collisionless laser-produced plasma, as determined by nonlinear criteria for weak and strong magnetization on the basis of the friction parameter Γ B and Alfven number M A, is considered within the Vlasov and Maxwell equations in the second part of the work. The flow velocities are lower then the thermal electron velocity. The energy and pulse anisotropy parameters of a flow, which determine its electromagnetic properties in the Cherenkov resonance line, are calculated by shape of particle distribution function (PDF). The ratio of these parameters is the Q-factor G V ; it characterizes the electromagnetic properties of a plasma flow and is expressed via the ratio of diamagnetic and resistive current densities or via the ratio of irregular and diamagnetic plasma scales. A particle flow is similar to a conductive medium at G V ≪ 1 and a diamagnetic medium at G V ≫ 1. The following cases are considered. (1) A plasma flow is specified by an isotropic PDF and interacts with distributed magnetization. Expressions for anisotropy parameters are derived, 3D field structures in the tail wake are found, and a possibility of topological reconstruction into a compact state under variation in the parameter G V is shown. (2) A plasma flow is specified by an isotropic PDF; a steady-state diamagnetic current layer, characterized by an anisotropic PDF, is immersed inside it. The system is in the diamagnetic state G ≫ 1. The generalized anisotropy parameter is calculated and a possibility of the excitation of three types of diamagnetic structures with low resistive currents is shown. (3) The nonlinear dynamics of anisotropic quasi-current-free plasma ( G =-1), in which the diamagnetic and resistive current densities locally compensate each other in the phase space of particle velocities, is studied. This dynamics is implemented in the long wavelength limit in plasma with an anisotropic PDF.

  3. PORTA: A Massively Parallel Code for 3D Non-LTE Polarized Radiative Transfer

    NASA Astrophysics Data System (ADS)

    Štěpán, J.

    2014-10-01

    The interpretation of the Stokes profiles of the solar (stellar) spectral line radiation requires solving a non-LTE radiative transfer problem that can be very complex, especially when the main interest lies in modeling the linear polarization signals produced by scattering processes and their modification by the Hanle effect. One of the main difficulties is due to the fact that the plasma of a stellar atmosphere can be highly inhomogeneous and dynamic, which implies the need to solve the non-equilibrium problem of generation and transfer of polarized radiation in realistic three-dimensional stellar atmospheric models. Here we present PORTA, a computer program we have developed for solving, in three-dimensional (3D) models of stellar atmospheres, the problem of the generation and transfer of spectral line polarization taking into account anisotropic radiation pumping and the Hanle and Zeeman effects in multilevel atoms. The numerical method of solution is based on a highly convergent iterative algorithm, whose convergence rate is insensitive to the grid size, and on an accurate short-characteristics formal solver of the Stokes-vector transfer equation which uses monotonic Bezier interpolation. In addition to the iterative method and the 3D formal solver, another important feature of PORTA is a novel parallelization strategy suitable for taking advantage of massively parallel computers. Linear scaling of the solution with the number of processors allows to reduce the solution time by several orders of magnitude. We present useful benchmarks and a few illustrations of applications using a 3D model of the solar chromosphere resulting from MHD simulations. Finally, we present our conclusions with a view to future research. For more details see Štěpán & Trujillo Bueno (2013).

  4. Three-dimensional inelastic analysis for hot section components, BEST 3D code

    NASA Technical Reports Server (NTRS)

    Wilson, Raymond B.; Banerjee, Prasanta K.

    1987-01-01

    The goal is the development of an alternative stress analysis tool, distinct from the finite element method, applicable to the engineering analysis of gas turbine engine structures. The boundary element method was selected for this development effort on the basis of its already demonstrated applicability to a variety of geometries and problem types characteristic of gas turbine engine components. Major features of the BEST3D computer program are described, and some of the significant developments carried out as part of the Inelastic Methods Contract are outlined.

  5. Validation and Comparison of 2D and 3D Codes for Nearshore Motion of Long Waves Using Benchmark Problems

    NASA Astrophysics Data System (ADS)

    Velioǧlu, Deniz; Cevdet Yalçıner, Ahmet; Zaytsev, Andrey

    2016-04-01

    Tsunamis are huge waves with long wave periods and wave lengths that can cause great devastation and loss of life when they strike a coast. The interest in experimental and numerical modeling of tsunami propagation and inundation increased considerably after the 2011 Great East Japan earthquake. In this study, two numerical codes, FLOW 3D and NAMI DANCE, that analyze tsunami propagation and inundation patterns are considered. Flow 3D simulates linear and nonlinear propagating surface waves as well as long waves by solving three-dimensional Navier-Stokes (3D-NS) equations. NAMI DANCE uses finite difference computational method to solve 2D depth-averaged linear and nonlinear forms of shallow water equations (NSWE) in long wave problems, specifically tsunamis. In order to validate these two codes and analyze the differences between 3D-NS and 2D depth-averaged NSWE equations, two benchmark problems are applied. One benchmark problem investigates the runup of long waves over a complex 3D beach. The experimental setup is a 1:400 scale model of Monai Valley located on the west coast of Okushiri Island, Japan. Other benchmark problem is discussed in 2015 National Tsunami Hazard Mitigation Program (NTHMP) Annual meeting in Portland, USA. It is a field dataset, recording the Japan 2011 tsunami in Hilo Harbor, Hawaii. The computed water surface elevation and velocity data are compared with the measured data. The comparisons showed that both codes are in fairly good agreement with each other and benchmark data. The differences between 3D-NS and 2D depth-averaged NSWE equations are highlighted. All results are presented with discussions and comparisons. Acknowledgements: Partial support by Japan-Turkey Joint Research Project by JICA on earthquakes and tsunamis in Marmara Region (JICA SATREPS - MarDiM Project), 603839 ASTARTE Project of EU, UDAP-C-12-14 project of AFAD Turkey, 108Y227, 113M556 and 213M534 projects of TUBITAK Turkey, RAPSODI (CONCERT_Dis-021) of CONCERT

  6. Evaluation of method of moments codes: University of Houston junction and numerical electromagnetic code

    NASA Astrophysics Data System (ADS)

    Rockway, J. W.; Logan, J. C.; Deneris, C. A.

    1991-10-01

    The principal goal of the Electromagnetic Compatibility (EMC) Project is to minimize exterior electromagnetic interference (EMI) problems during the life-cycle of Navy surface ships. An important aspect of mitigating exterior EMI problems is the characterization of antenna performance. At the present time, for shipboard MF and HF (2 to 30 MHz) antennas, there exists two techniques for performing a topside antenna study: brass scale modeling and numerical modeling. Brass scale models have a few drawbacks: they are time-consuming to build, difficult to rapidly modify, troublesome to accurately measure near fields on scale models, and they are somewhat limited in their application. This report is an evaluation of the progress in development of two advanced computer programs for antenna modeling. One is the performance of the JUNCTION Code, under development at the University of Houston, and the other is the performance of the Numerical Electromagnetic Code - Version 4 (NEC4) being developed at the Lawrence Livermore National Laboratory.

  7. 3-D kinetics simulations of the NRU reactor using the DONJON code

    SciTech Connect

    Leung, T. C.; Atfield, M. D.; Koclas, J.

    2006-07-01

    The NRU reactor is highly heterogeneous, heavy-water cooled and moderated, with online refuelling capability. It is licensed to operate at a maximum power of 135 MW, with a peak thermal flux of approximately 4.0 x 10{sup 18} n.m{sup -2} . s{sup -1}. In support of the safe operation of NRU, three-dimensional kinetics calculations for reactor transients have been performed using the DONJON code. The code was initially designed to perform space-time kinetics calculations for the CANDU{sup R} power reactors. This paper describes how the DONJON code can be applied to perform neutronic simulations for the analysis of reactor transients in NRU, and presents calculation results for some transients. (authors)

  8. Numerical simulation of jet aerodynamics using the three-dimensional Navier-Stokes code PAB3D

    NASA Technical Reports Server (NTRS)

    Pao, S. Paul; Abdol-Hamid, Khaled S.

    1996-01-01

    This report presents a unified method for subsonic and supersonic jet analysis using the three-dimensional Navier-Stokes code PAB3D. The Navier-Stokes code was used to obtain solutions for axisymmetric jets with on-design operating conditions at Mach numbers ranging from 0.6 to 3.0, supersonic jets containing weak shocks and Mach disks, and supersonic jets with nonaxisymmetric nozzle exit geometries. This report discusses computational methods, code implementation, computed results, and comparisons with available experimental data. Very good agreement is shown between the numerical solutions and available experimental data over a wide range of operating conditions. The Navier-Stokes method using the standard Jones-Launder two-equation kappa-epsilon turbulence model can accurately predict jet flow, and such predictions are made without any modification to the published constants for the turbulence model.

  9. Application of ATHLET/DYN3D coupled codes system for fast liquid metal cooled reactor steady state simulation

    NASA Astrophysics Data System (ADS)

    Ivanov, V.; Samokhin, A.; Danicheva, I.; Khrennikov, N.; Bouscuet, J.; Velkov, K.; Pasichnyk, I.

    2017-01-01

    In this paper the approaches used for developing of the BN-800 reactor test model and for validation of coupled neutron-physic and thermohydraulic calculations are described. Coupled codes ATHLET 3.0 (code for thermohydraulic calculations of reactor transients) and DYN3D (3-dimensional code of neutron kinetics) are used for calculations. The main calculation results of reactor steady state condition are provided. 3-D model used for neutron calculations was developed for start reactor BN-800 load. The homogeneous approach is used for description of reactor assemblies. Along with main simplifications, the main reactor BN-800 core zones are described (LEZ, MEZ, HEZ, MOX, blankets). The 3D neutron physics calculations were provided with 28-group library, which is based on estimated nuclear data ENDF/B-7.0. Neutron SCALE code was used for preparation of group constants. Nodalization hydraulic model has boundary conditions by coolant mass-flow rate for core inlet part, by pressure and enthalpy for core outlet part, which can be chosen depending on reactor state. Core inlet and outlet temperatures were chosen according to reactor nominal state. The coolant mass flow rate profiling through the core is based on reactor power distribution. The test thermohydraulic calculations made with using of developed model showed acceptable results in coolant mass flow rate distribution through the reactor core and in axial temperature and pressure distribution. The developed model will be upgraded in future for different transient analysis in metal-cooled fast reactors of BN type including reactivity transients (control rods withdrawal, stop of the main circulation pump, etc.).

  10. Acoustic Scattering by Three-Dimensional Stators and Rotors Using the SOURCE3D Code. Volume 1; Analysis and Results

    NASA Technical Reports Server (NTRS)

    Meyer, Harold D.

    1999-01-01

    This report provides a study of rotor and stator scattering using the SOURCE3D Rotor Wake/Stator Interaction Code. SOURCE3D is a quasi-three-dimensional computer program that uses three-dimensional acoustics and two-dimensional cascade load response theory to calculate rotor and stator modal reflection and transmission (scattering) coefficients. SOURCE3D is at the core of the TFaNS (Theoretical Fan Noise Design/Prediction System), developed for NASA, which provides complete fully coupled (inlet, rotor, stator, exit) noise solutions for turbofan engines. The reason for studying scattering is that we must first understand the behavior of the individual scattering coefficients provided by SOURCE3D, before eventually understanding the more complicated predictions from TFaNS. To study scattering, we have derived a large number of scattering curves for vane and blade rows. The curves are plots of output wave power divided by input wave power (in dB units) versus vane/blade ratio. Some of these plots are shown in this report. All of the plots are provided in a separate volume. To assist in understanding the plots, formulas have been derived for special vane/blade ratios for which wavefronts are either parallel or normal to rotor or stator chords. From the plots, we have found that, for the most part, there was strong transmission and weak reflection over most of the vane/blade ratio range for the stator. For the rotor, there was little transmission loss.

  11. Full-physics 3D heterogeneous simulations of electromagnetic induction fields on level and deformed sea ice

    SciTech Connect

    Samluk, Jesse P.; Geiger, Cathleen A.; Weiss, Chester J.; Kolodzey, James

    2015-10-01

    In this article we explore simulated responses of electromagnetic (EM) signals relative to in situ field surveys and quantify the effects that different values of conductivity in sea ice have on the EM fields. We compute EM responses of ice types with a three-dimensional (3-D) finite-volume discretization of Maxwell's equations and present 2-D sliced visualizations of their associated EM fields at discrete frequencies. Several interesting observations result: First, since the simulator computes the fields everywhere, each gridcell acts as a receiver within the model volume, and captures the complete, coupled interactions between air, snow, sea ice and sea water as a function of their conductivity; second, visualizations demonstrate how 1-D approximations near deformed ice features are violated. But the most important new finding is that changes in conductivity affect EM field response by modifying the magnitude and spatial patterns (i.e. footprint size and shape) of current density and magnetic fields. These effects are demonstrated through a visual feature we define as 'null lines'. Null line shape is affected by changes in conductivity near material boundaries as well as transmitter location. Our results encourage the use of null lines as a planning tool for better ground-truth field measurements near deformed ice types.

  12. Full-physics 3D heterogeneous simulations of electromagnetic induction fields on level and deformed sea ice

    DOE PAGES

    Samluk, Jesse P.; Geiger, Cathleen A.; Weiss, Chester J.; ...

    2015-10-01

    In this article we explore simulated responses of electromagnetic (EM) signals relative to in situ field surveys and quantify the effects that different values of conductivity in sea ice have on the EM fields. We compute EM responses of ice types with a three-dimensional (3-D) finite-volume discretization of Maxwell's equations and present 2-D sliced visualizations of their associated EM fields at discrete frequencies. Several interesting observations result: First, since the simulator computes the fields everywhere, each gridcell acts as a receiver within the model volume, and captures the complete, coupled interactions between air, snow, sea ice and sea water asmore » a function of their conductivity; second, visualizations demonstrate how 1-D approximations near deformed ice features are violated. But the most important new finding is that changes in conductivity affect EM field response by modifying the magnitude and spatial patterns (i.e. footprint size and shape) of current density and magnetic fields. These effects are demonstrated through a visual feature we define as 'null lines'. Null line shape is affected by changes in conductivity near material boundaries as well as transmitter location. Our results encourage the use of null lines as a planning tool for better ground-truth field measurements near deformed ice types.« less

  13. A parallel 3-D discrete wavelet transform architecture using pipelined lifting scheme approach for video coding

    NASA Astrophysics Data System (ADS)

    Hegde, Ganapathi; Vaya, Pukhraj

    2013-10-01

    This article presents a parallel architecture for 3-D discrete wavelet transform (3-DDWT). The proposed design is based on the 1-D pipelined lifting scheme. The architecture is fully scalable beyond the present coherent Daubechies filter bank (9, 7). This 3-DDWT architecture has advantages such as no group of pictures restriction and reduced memory referencing. It offers low power consumption, low latency and high throughput. The computing technique is based on the concept that lifting scheme minimises the storage requirement. The application specific integrated circuit implementation of the proposed architecture is done by synthesising it using 65 nm Taiwan Semiconductor Manufacturing Company standard cell library. It offers a speed of 486 MHz with a power consumption of 2.56 mW. This architecture is suitable for real-time video compression even with large frame dimensions.

  14. Applications of the 3-D Deterministic Transport Code Attlla for Core Safety Analysis

    SciTech Connect

    D. S. Lucas

    2004-10-01

    An LDRD (Laboratory Directed Research and Development) project is ongoing at the Idaho National Engineering and Environmental Laboratory (INEEL) for applying the three-dimensional multi-group deterministic neutron transport code (Attila®) to criticality, flux and depletion calculations of the Advanced Test Reactor (ATR). This paper discusses the model development, capabilities of Attila, generation of the cross-section libraries, and comparisons to an ATR MCNP model and future.

  15. Drug-laden 3D biodegradable label using QR code for anti-counterfeiting of drugs.

    PubMed

    Fei, Jie; Liu, Ran

    2016-06-01

    Wiping out counterfeit drugs is a great task for public health care around the world. The boost of these drugs makes treatment to become potentially harmful or even lethal. In this paper, biodegradable drug-laden QR code label for anti-counterfeiting of drugs is proposed that can provide the non-fluorescence recognition and high capacity. It is fabricated by the laser cutting to achieve the roughness over different surface which causes the difference in the gray levels on the translucent material the QR code pattern, and the micro mold process to obtain the drug-laden biodegradable label. We screened biomaterials presenting the relevant conditions and further requirements of the package. The drug-laden microlabel is on the surface of the troches or the bottom of the capsule and can be read by a simple smartphone QR code reader application. Labeling the pill directly and decoding the information successfully means more convenient and simple operation with non-fluorescence and high capacity in contrast to the traditional methods.

  16. A treatment planning code for inverse planning and 3D optimization in hadrontherapy.

    PubMed

    Bourhaleb, F; Marchetto, F; Attili, A; Pittà, G; Cirio, R; Donetti, M; Giordanengo, S; Givehchi, N; Iliescu, S; Krengli, M; La Rosa, A; Massai, D; Pecka, A; Pardo, J; Peroni, C

    2008-09-01

    The therapeutic use of protons and ions, especially carbon ions, is a new technique and a challenge to conform the dose to the target due to the energy deposition characteristics of hadron beams. An appropriate treatment planning system (TPS) is strictly necessary to take full advantage. We developed a TPS software, ANCOD++, for the evaluation of the optimal conformal dose. ANCOD++ is an analytical code using the voxel-scan technique as an active method to deliver the dose to the patient, and provides treatment plans with both proton and carbon ion beams. The iterative algorithm, coded in C++ and running on Unix/Linux platform, allows the determination of the best fluences of the individual beams to obtain an optimal physical dose distribution, delivering a maximum dose to the target volume and a minimum dose to critical structures. The TPS is supported by Monte Carlo simulations with the package GEANT3 to provide the necessary physical lookup tables and verify the optimized treatment plans. Dose verifications done by means of full Monte Carlo simulations show an overall good agreement with the treatment planning calculations. We stress the fact that the purpose of this work is the verification of the physical dose and a next work will be dedicated to the radiobiological evaluation of the equivalent biological dose.

  17. Embedded morphological dilation coding for 2D and 3D images

    NASA Astrophysics Data System (ADS)

    Lazzaroni, Fabio; Signoroni, Alberto; Leonardi, Riccardo

    2002-01-01

    Current wavelet-based image coders obtain high performance thanks to the identification and the exploitation of the statistical properties of natural images in the transformed domain. Zerotree-based algorithms, as Embedded Zerotree Wavelets (EZW) and Set Partitioning In Hierarchical Trees (SPIHT), offer high Rate-Distortion (RD) coding performance and low computational complexity by exploiting statistical dependencies among insignificant coefficients on hierarchical subband structures. Another possible approach tries to predict the clusters of significant coefficients by means of some form of morphological dilation. An example of a morphology-based coder is the Significance-Linked Connected Component Analysis (SLCCA) that has shown performance which are comparable to the zerotree-based coders but is not embedded. A new embedded bit-plane coder is proposed here based on morphological dilation of significant coefficients and context based arithmetic coding. The algorithm is able to exploit both intra-band and inter-band statistical dependencies among wavelet significant coefficients. Moreover, the same approach is used both for two and three-dimensional wavelet-based image compression. Finally we the algorithms are tested on some 2D images and on a medical volume, by comparing the RD results to those obtained with the state-of-the-art wavelet-based coders.

  18. Code and Solution Verification of 3D Numerical Modeling of Flow in the Gust Erosion Chamber

    NASA Astrophysics Data System (ADS)

    Yuen, A.; Bombardelli, F. A.

    2014-12-01

    Erosion microcosms are devices commonly used to investigate the erosion and transport characteristics of sediments at the bed of rivers, lakes, or estuaries. In order to understand the results these devices provide, the bed shear stress and flow field need to be accurately described. In this research, the UMCES Gust Erosion Microcosm System (U-GEMS) is numerically modeled using Finite Volume Method. The primary aims are to simulate the bed shear stress distribution at the surface of the sediment core/bottom of the microcosm, and to validate the U-GEMS produces uniform bed shear stress at the bottom of the microcosm. The mathematical model equations are solved by on a Cartesian non-uniform grid. Multiple numerical runs were developed with different input conditions and configurations. Prior to developing the U-GEMS model, the General Moving Objects (GMO) model and different momentum algorithms in the code were verified. Code verification of these solvers was done via simulating the flow inside the top wall driven square cavity on different mesh sizes to obtain order of convergence. The GMO model was used to simulate the top wall in the top wall driven square cavity as well as the rotating disk in the U-GEMS. Components simulated with the GMO model were rigid bodies that could have any type of motion. In addition cross-verification was conducted as results were compared with numerical results by Ghia et al. (1982), and good agreement was found. Next, CFD results were validated by simulating the flow within the conventional microcosm system without suction and injection. Good agreement was found when the experimental results by Khalili et al. (2008) were compared. After the ability of the CFD solver was proved through the above code verification steps. The model was utilized to simulate the U-GEMS. The solution was verified via classic mesh convergence study on four consecutive mesh sizes, in addition to that Grid Convergence Index (GCI) was calculated and based on

  19. Validation of a Node-Centered Wall Function Model for the Unstructured Flow Code FUN3D

    NASA Technical Reports Server (NTRS)

    Carlson, Jan-Renee; Vasta, Veer N.; White, Jeffery

    2015-01-01

    In this paper, the implementation of two wall function models in the Reynolds averaged Navier-Stokes (RANS) computational uid dynamics (CFD) code FUN3D is described. FUN3D is a node centered method for solving the three-dimensional Navier-Stokes equations on unstructured computational grids. The first wall function model, based on the work of Knopp et al., is used in conjunction with the one-equation turbulence model of Spalart-Allmaras. The second wall function model, also based on the work of Knopp, is used in conjunction with the two-equation k-! turbulence model of Menter. The wall function models compute the wall momentum and energy flux, which are used to weakly enforce the wall velocity and pressure flux boundary conditions in the mean flow momentum and energy equations. These wall conditions are implemented in an implicit form where the contribution of the wall function model to the Jacobian are also included. The boundary conditions of the turbulence transport equations are enforced explicitly (strongly) on all solid boundaries. The use of the wall function models is demonstrated on four test cases: a at plate boundary layer, a subsonic di user, a 2D airfoil, and a 3D semi-span wing. Where possible, different near-wall viscous spacing tactics are examined. Iterative residual convergence was obtained in most cases. Solution results are compared with theoretical and experimental data for several variations of grid spacing. In general, very good comparisons with data were achieved.

  20. Predictions of bubbly flows in vertical pipes using two-fluid models in CFDS-FLOW3D code

    SciTech Connect

    Banas, A.O.; Carver, M.B.; Unrau, D.

    1995-09-01

    This paper reports the results of a preliminary study exploring the performance of two sets of two-fluid closure relationships applied to the simulation of turbulent air-water bubbly upflows through vertical pipes. Predictions obtained with the default CFDS-FLOW3D model for dispersed flows were compared with the predictions of a new model (based on the work of Lee), and with the experimental data of Liu. The new model, implemented in the CFDS-FLOW3D code, included additional source terms in the {open_quotes}standard{close_quotes} {kappa}-{epsilon} transport equations for the liquid phase, as well as modified model coefficients and wall functions. All simulations were carried out in a 2-D axisymmetric format, collapsing the general multifluid framework of CFDS-FLOW3D to the two-fluid (air-water) case. The newly implemented model consistently improved predictions of radial-velocity profiles of both phases, but failed to accurately reproduce the experimental phase-distribution data. This shortcoming was traced to the neglect of anisotropic effects in the modelling of liquid-phase turbulence. In this sense, the present investigation should be considered as the first step toward the ultimate goal of developing a theoretically sound and universal CFD-type two-fluid model for bubbly flows in channels.

  1. CFD Code Calibration and Inlet-Fairing Effects On a 3D Hypersonic Powered-Simulation Model

    NASA Technical Reports Server (NTRS)

    Huebner, Lawrence D.; Tatum, Kenneth E.

    1993-01-01

    A three-dimensional (3D) computational study has been performed addressing issues related to the wind tunnel testing of a hypersonic powered-simulation model. The study consisted of three objectives. The first objective was to calibrate a state-of-the-art computational fluid dynamics (CFD) code in its ability to predict hypersonic powered-simulation flows by comparing CFD solutions with experimental surface pressure data. Aftbody lower surface pressures were well predicted, but lower surface wing pressures were less accurately predicted. The second objective was to determine the 3D effects on the aftbody created by fairing over the inlet; this was accomplished by comparing the CFD solutions of two closed-inlet powered configurations with a flowing- inlet powered configuration. Although results at four freestream Mach numbers indicate that the exhaust plume tends to isolate the aftbody surface from most forebody flow- field differences, a smooth inlet fairing provides the least aftbody force and moment variation compared to a flowing inlet. The final objective was to predict and understand the 3D characteristics of exhaust plume development at selected points on a representative flight path. Results showed a dramatic effect of plume expansion onto the wings as the freestream Mach number and corresponding nozzle pressure ratio are increased.

  2. DISCO: A 3D Moving-mesh Magnetohydrodynamics Code Designed for the Study of Astrophysical Disks

    NASA Astrophysics Data System (ADS)

    Duffell, Paul C.

    2016-09-01

    This work presents the publicly available moving-mesh magnetohydrodynamics (MHD) code DISCO. DISCO is efficient and accurate at evolving orbital fluid motion in two and three dimensions, especially at high Mach numbers. DISCO employs a moving-mesh approach utilizing a dynamic cylindrical mesh that can shear azimuthally to follow the orbital motion of the gas. The moving mesh removes diffusive advection errors and allows for longer time-steps than a static grid. MHD is implemented in DISCO using an HLLD Riemann solver and a novel constrained transport (CT) scheme that is compatible with the mesh motion. DISCO is tested against a wide variety of problems, which are designed to test its stability, accuracy, and scalability. In addition, several MHD tests are performed which demonstrate the accuracy and stability of the new CT approach, including two tests of the magneto-rotational instability, one testing the linear growth rate and the other following the instability into the fully turbulent regime.

  3. Extension of a three-dimensional viscous wing flow analysis user's manual: VISTA 3-D code

    NASA Technical Reports Server (NTRS)

    Weinberg, Bernard C.; Chen, Shyi-Yaung; Thoren, Stephen J.; Shamroth, Stephen J.

    1990-01-01

    Three-dimensional unsteady viscous effects can significantly influence the performance of fixed and rotary wing aircraft. These effects are important in both flows about helicopter rotors in forward flight and flows about three-dimensional (swept and tapered) supercritical wings. A computational procedure for calculating such flow field was developed. The procedure is based upon an alternating direction technique employing the Linearized Block Implicit method for solving three-dimensional viscous flow problems. In order to demonstrate the viability of this method, two- and three-dimensional problems are computed. These include the flow over a two-dimensional NACA 0012 airfoil under steady and oscillating conditions, and the steady, skewed, three-dimensional flow on a flat plate. Although actual three-dimensional flows over wings were not obtained, the ground work was laid for considering such flows. In this report a description of the computer code is given.

  4. Development of Scientific Simulation 3D Full Wave ICRF Code for Stellarators and Heating/CD Scenarios Development

    SciTech Connect

    Vdovin V.L.

    2005-08-15

    In this report we describe theory and 3D full wave code description for the wave excitation, propagation and absorption in 3-dimensional (3D) stellarator equilibrium high beta plasma in ion cyclotron frequency range (ICRF). This theory forms a basis for a 3D code creation, urgently needed for the ICRF heating scenarios development for the operated LHD, constructed W7-X, NCSX and projected CSX3 stellarators, as well for re evaluation of ICRF scenarios in operated tokamaks and in the ITER . The theory solves the 3D Maxwell-Vlasov antenna-plasma-conducting shell boundary value problem in the non-orthogonal flux coordinates ({Psi}, {theta}, {var_phi}), {Psi} being magnetic flux function, {theta} and {var_phi} being the poloidal and toroidal angles, respectively. All basic physics, like wave refraction, reflection and diffraction are self consistently included, along with the fundamental ion and ion minority cyclotron resonances, two ion hybrid resonance, electron Landau and TTMP absorption. Antenna reactive impedance and loading resistance are also calculated and urgently needed for an antenna -generator matching. This is accomplished in a real confining magnetic field being varying in a plasma major radius direction, in toroidal and poloidal directions, through making use of the hot dense plasma wave induced currents with account to the finite Larmor radius effects. We expand the solution in Fourier series over the toroidal ({var_phi}) and poloidal ({theta}) angles and solve resulting ordinary differential equations in a radial like {Psi}-coordinate by finite difference method. The constructed discretization scheme is divergent-free one, thus retaining the basic properties of original equations. The Fourier expansion over the angle coordinates has given to us the possibility to correctly construct the ''parallel'' wave number k{sub //}, and thereby to correctly describe the ICRF waves absorption by a hot plasma. The toroidal harmonics are tightly coupled with each

  5. Self-Propagating Combustion Triggered Synthesis of 3D Lamellar Graphene/BaFe12O19 Composite and Its Electromagnetic Wave Absorption Properties

    PubMed Central

    Zhao, Tingkai; Ji, Xianglin; Jin, Wenbo; Yang, Wenbo; Peng, Xiarong; Duan, Shichang; Dang, Alei; Li, Hao; Li, Tiehu

    2017-01-01

    The synthesis of 3D lamellar graphene/BaFe12O19 composites was performed by oxidizing graphite and sequentially self-propagating combustion triggered process. The 3D lamellar graphene structures were formed due to the synergistic effect of the tremendous heat induced gasification as well as huge volume expansion. The 3D lamellar graphene/BaFe12O19 composites bearing 30 wt % graphene present the reflection loss peak at −27.23 dB as well as the frequency bandwidth at 2.28 GHz (< −10 dB). The 3D lamellar graphene structures could consume the incident waves through multiple reflection and scattering within the layered structures, prolonging the propagation path of electromagnetic waves in the absorbers. PMID:28336889

  6. New laser driver for physics modeling codes using unstructured 3d grids

    SciTech Connect

    Kaiser, T; Milovich, J L; Prasad, M K; Shestakov, A I

    1999-02-01

    We present a status report on the current state of development, testing and application of a new scheme for laser beam evolution and power deposition on three-dimensional unstructured grids. The scheme is being encapsulated in a C++ library for convenient porting to existing modeling codes. We have added a new ray propagator that is second order in time, allowing rays to refract within computational zones as well as at zone interfaces. In a globally constant free-electron density gradient on a randomized hexahedral mesh,the new integrator produces ray trajectories that agree with analytic results to within machine roundoff. A new method for computing the inverse-bremmstrahlung energy deposition rate that captures its highly non-uniform spatial dependence within a zone has also been added. This allows accurate trajectories without the necessity of sub-stepping in time. Other enhancements (not discussed) include multiple user-configurable beams, computation of the electron oscillation velocity in the laser electric field and energy-deposition accounting. Results of laser-driven simulations are presented in a companion paper.

  7. A Fast Parallel Simulation Code for Interaction between Proto-Planetary Disk and Embedded Proto-Planets: Implementation for 3D Code

    SciTech Connect

    Li, Shengtai; Li, Hui

    2012-06-14

    We develop a 3D simulation code for interaction between the proto-planetary disk and embedded proto-planets. The protoplanetary disk is treated as a three-dimensional (3D), self-gravitating gas whose motion is described by the locally isothermal Navier-Stokes equations in a spherical coordinate centered on the star. The differential equations for the disk are similar to those given in Kley et al. (2009) with a different gravitational potential that is defined in Nelson et al. (2000). The equations are solved by directional split Godunov method for the inviscid Euler equations plus operator-split method for the viscous source terms. We use a sub-cycling technique for the azimuthal sweep to alleviate the time step restriction. We also extend the FARGO scheme of Masset (2000) and modified in Li et al. (2001) to our 3D code to accelerate the transport in the azimuthal direction. Furthermore, we have implemented a reduced 2D (r, {theta}) and a fully 3D self-gravity solver on our uniform disk grid, which extends our 2D method (Li, Buoni, & Li 2008) to 3D. This solver uses a mode cut-off strategy and combines FFT in the azimuthal direction and direct summation in the radial and meridional direction. An initial axis-symmetric equilibrium disk is generated via iteration between the disk density profile and the 2D disk-self-gravity. We do not need any softening in the disk self-gravity calculation as we have used a shifted grid method (Li et al. 2008) to calculate the potential. The motion of the planet is limited on the mid-plane and the equations are the same as given in D'Angelo et al. (2005), which we adapted to the polar coordinates with a fourth-order Runge-Kutta solver. The disk gravitational force on the planet is assumed to evolve linearly with time between two hydrodynamics time steps. The Planetary potential acting on the disk is calculated accurately with a small softening given by a cubic-spline form (Kley et al. 2009). Since the torque is extremely sensitive to

  8. Multi-code benchmark of global gyrokinetic electromagnetic instabilities

    NASA Astrophysics Data System (ADS)

    Goerler, Tobias; Bottino, Alberto; Hornsby, William A.; Kleiber, Ralf; Tronko, Natalia; Grandgirard, Virginie; Norscini, Claudia; Sonnendruecker, Eric

    2015-11-01

    Considering the recent major extensions of global gyrokinetic codes towards a comprehensive and self-consistent treatment of electromagnetic (EM) effects, corresponding verification tests are obvious and necessary steps to be taken. While a number of (semi-)analytic test cases and benchmarks exist in the axisymmetric limit, microinstabilities and particularly EM turbulence are rarely addressed. In order to remedy this problem, a hierarchical linear gyrokinetic benchmark study is presented starting with electrostatic ion temperature gradient microinstabilities with adiabatic electron response and progressing finally to the characterization of fully EM instabilities as a function of β. The inter-code comparison involves contributions from Eulerian Vlasov, Lagrangian PIC, and Semi-Lagrange codes at least in one level of this verification exercise, thus confirming a high degree of reliability for the implementations that has rarely been achieved before in this context. Additionally, possible extensions of this benchmark into the physically more relevant nonlinear turbulence regime will be discussed, e.g., relaxation problems or gradient-driven setups. This work has been carried out within the framework of the EUROfusion Consortium.

  9. Modeling Warm Dense Matter Experiments using the 3D ALE-AMR Code and the Move Toward Exascale Computing

    SciTech Connect

    Koniges, A; Eder, E; Liu, W; Barnard, J; Friedman, A; Logan, G; Fisher, A; Masers, N; Bertozzi, A

    2011-11-04

    The Neutralized Drift Compression Experiment II (NDCX II) is an induction accelerator planned for initial commissioning in 2012. The final design calls for a 3 MeV, Li+ ion beam, delivered in a bunch with characteristic pulse duration of 1 ns, and transverse dimension of order 1 mm. The NDCX II will be used in studies of material in the warm dense matter (WDM) regime, and ion beam/hydrodynamic coupling experiments relevant to heavy ion based inertial fusion energy. We discuss recent efforts to adapt the 3D ALE-AMR code to model WDM experiments on NDCX II. The code, which combines Arbitrary Lagrangian Eulerian (ALE) hydrodynamics with Adaptive Mesh Refinement (AMR), has physics models that include ion deposition, radiation hydrodynamics, thermal diffusion, anisotropic material strength with material time history, and advanced models for fragmentation. Experiments at NDCX-II will explore the process of bubble and droplet formation (two-phase expansion) of superheated metal solids using ion beams. Experiments at higher temperatures will explore equation of state and heavy ion fusion beam-to-target energy coupling efficiency. Ion beams allow precise control of local beam energy deposition providing uniform volumetric heating on a timescale shorter than that of hydrodynamic expansion. The ALE-AMR code does not have any export control restrictions and is currently running at the National Energy Research Scientific Computing Center (NERSC) at LBNL and has been shown to scale well to thousands of CPUs. New surface tension models that are being implemented and applied to WDM experiments. Some of the approaches use a diffuse interface surface tension model that is based on the advective Cahn-Hilliard equations, which allows for droplet breakup in divergent velocity fields without the need for imposed perturbations. Other methods require seeding or other methods for droplet breakup. We also briefly discuss the effects of the move to exascale computing and related

  10. A study of the earth radiation budget using a 3D Monte-Carlo radiative transer code

    NASA Astrophysics Data System (ADS)

    Okata, M.; Nakajima, T.; Sato, Y.; Inoue, T.; Donovan, D. P.

    2013-12-01

    The purpose of this study is to evaluate the earth's radiation budget when data are available from satellite-borne active sensors, i.e. cloud profiling radar (CPR) and lidar, and a multi-spectral imager (MSI) in the project of the Earth Explorer/EarthCARE mission. For this purpose, we first developed forward and backward 3D Monte Carlo radiative transfer codes that can treat a broadband solar flux calculation including thermal infrared emission calculation by k-distribution parameters of Sekiguchi and Nakajima (2008). In order to construct the 3D cloud field, we tried the following three methods: 1) stochastic cloud generated by randomized optical thickness each layer distribution and regularly-distributed tilted clouds, 2) numerical simulations by a non-hydrostatic model with bin cloud microphysics model and 3) Minimum cloud Information Deviation Profiling Method (MIDPM) as explained later. As for the method-2 (numerical modeling method), we employed numerical simulation results of Californian summer stratus clouds simulated by a non-hydrostatic atmospheric model with a bin-type cloud microphysics model based on the JMA NHM model (Iguchi et al., 2008; Sato et al., 2009, 2012) with horizontal (vertical) grid spacing of 100m (20m) and 300m (20m) in a domain of 30km (x), 30km (y), 1.5km (z) and with a horizontally periodic lateral boundary condition. Two different cell systems were simulated depending on the cloud condensation nuclei (CCN) concentration. In the case of horizontal resolution of 100m, regionally averaged cloud optical thickness, , and standard deviation of COT, were 3.0 and 4.3 for pristine case and 8.5 and 7.4 for polluted case, respectively. In the MIDPM method, we first construct a library of pair of observed vertical profiles from active sensors and collocated imager products at the nadir footprint, i.e. spectral imager radiances, cloud optical thickness (COT), effective particle radius (RE) and cloud top temperature (Tc). We then select a

  11. Parameter analysis for a high-gain harmonic generation FEL using a recently developed 3D polychromatic code.

    SciTech Connect

    Biedron, S. G.; Freund, H. P.; Yu, L.-H.

    1999-09-10

    One possible design for a fourth-generation light source is the high-gain harmonic generation (HGHG) free-electron laser (FEL). Here, a coherent seed with a wavelength at a subharmonic of the desired output radiation interacts with the electron beam in an energy-modulating section. This energy modulation is then converted into spatial bunching while traversing a dispersive section (a three-dipole chicane). The final step is passage through a radiative section, an undulator tuned to the desired higher harmonic output wavelength. The coherent seed serves to remove noise and can be at a much lower subharmonic of the output radiation, thus eliminating the concerns found in self-amplified spontaneous emission (SASE) and seeded FELs, respectively. Recently, a 3D code that includes multiple frequencies, multiple undulatory (both in quantity and/or type), quadruple magnets, and dipole magnets was developed to easily simulate HGHG. Here, a brief review of the HGHG theory, the code development, the Accelerator Test Facility's (ATF) HGHG FEL experimental parameters, and the parameter analysis from simulations of this specific experiment will be discussed.

  12. 3D printed electromagnetic transmission and electronic structures fabricated on a single platform using advanced process integration techniques

    NASA Astrophysics Data System (ADS)

    Deffenbaugh, Paul Issac

    3D printing has garnered immense attention from many fields including in-office rapid prototyping of mechanical parts, outer-space satellite replication, garage functional firearm manufacture, and NASA rocket engine component fabrication. 3D printing allows increased design flexibility in the fabrication of electronics, microwave circuits and wireless antennas and has reached a level of maturity which allows functional parts to be printed. Much more work is necessary in order to perfect the processes of 3D printed electronics especially in the area of automation. Chapter 1 shows several finished prototypes of 3D printed electronics as well as newly developed techniques in fabrication. Little is known about the RF and microwave properties and applications of the standard materials which have been developed for 3D printing. Measurement of a wide variety of materials over a broad spectrum of frequencies up to 10 GHz using a variety of well-established measurement methods is performed throughout chapter 2. Several types of high frequency RF transmission lines are fabricated and valuable model-matched data is gathered and provided in chapter 3 for future designers' use. Of particular note is a fully 3D printed stripline which was automatically fabricated in one process on one machine. Some core advantages of 3D printing RF/microwave components include rapid manufacturing of complex, dimensionally sensitive circuits (such as antennas and filters which are often iteratively tuned) and the ability to create new devices that cannot be made using standard fabrication techniques. Chapter 4 describes an exemplary fully 3D printed curved inverted-F antenna.

  13. Time-dependent distribution functions and resulting synthetic NPA spectra in C-Mod calculated with the CQL3D-Hybrid-FOW, AORSA full-wave, and DC Lorentz codes

    NASA Astrophysics Data System (ADS)

    Harvey, R. W.; Petrov, Yu.; Jaeger, E. F.; Berry, L. A.; Bonoli, P. T.; Bader, A.

    2015-12-01

    A time-dependent simulation of C-Mod pulsed TCRF power is made obtaining minority hydrogen ion distributions with the CQL3D-Hybrid-FOW finite-orbit-width Fokker-Planck code. Cyclotron-resonant TCRF fields are calculated with the AORSA full wave code. The RF diffusion coefficients used in CQL3D are obtained with the DC Lorentz gyro-orbit code for perturbed particle trajectories in the combined equilibrium and TCRF electromagnetic fields. Prior results with a zero-banana-width simulation using the CQL3D/AORSA/DC time-cycles showed a pronounced enhancement of the H distribution in the perpendicular velocity direction compared to results obtained from Stix's quasilinear theory, and this substantially increased the rampup rate of the observed vertically-viewed neutral particle analyzer (NPA) flux, in general agreement with experiment. However, ramp down of the NPA flux after the pulse, remained long compared to the experiment. The present study compares the new FOW results, including relevant gyro-radius effects, to determine the importance of these new effects on the the NPA time-dependence.

  14. Runaway electron distributions obtained with the CQL3D Fokker-Planck code under tokamak disruption conditions

    SciTech Connect

    Harvey, R.W.; Chan, V.S.

    1996-12-31

    Runaway of electrons to high energy during plasma disruptions occurs due to large induced toroidal electric fields which tend to maintain the toroidal plasma current, in accord with Lenz law. This has been observed in many tokamaks. Within the closed flux surfaces, the bounce-averaged CQL3D Fokker-Planck code is well suited to obtain the resulting electron distributions, nonthermal contributions to electrical conductivity, and runaway rates. The time-dependent 2D in momentum-space (p{sub {parallel}} and p{sub {perpendicular}}) distributions axe calculated on a radial array of noncircular flux surfaces, including bounce-averaging of the Fokker-Planck equation to account for toroidal trapping effects. In the steady state, the resulting distributions represent a balance between applied toroidal electric field, relativistic Coulomb collisions, and synchrotron radiation. The code can be run in a mode where the electrons are sourced at low velocity and run off the high velocity edge of the computational mesh, giving runaway rates at steady state. At small minor radius, the results closely match previous results reported by Kulsrud et al. It is found that the runaway rate has a strong dependence on inverse aspect ratio e, decreasing by a factor {approx} 5 as e increases from 0.0 to 0.3. The code can also be run with a radial diffusion and pinching term, simulating radial transport with plasma pinching to maintain a given density profile. Results show a transport reduction of runaways in the plasma center, and an enhancement towards the edge due to the electrons from the plasma center. Avalanching of runaways due to a knock-on electron source is being included.

  15. Development and application of a ray-tracing code integrating with 3D equilibrium mapping in LHD ECH experiments

    NASA Astrophysics Data System (ADS)

    Tsujimura, T., Ii; Kubo, S.; Takahashi, H.; Makino, R.; Seki, R.; Yoshimura, Y.; Igami, H.; Shimozuma, T.; Ida, K.; Suzuki, C.; Emoto, M.; Yokoyama, M.; Kobayashi, T.; Moon, C.; Nagaoka, K.; Osakabe, M.; Kobayashi, S.; Ito, S.; Mizuno, Y.; Okada, K.; Ejiri, A.; Mutoh, T.

    2015-11-01

    The central electron temperature has successfully reached up to 7.5 keV in large helical device (LHD) plasmas with a central high-ion temperature of 5 keV and a central electron density of 1.3× {{10}19} m-3. This result was obtained by heating with a newly-installed 154 GHz gyrotron and also the optimisation of injection geometry in electron cyclotron heating (ECH). The optimisation was carried out by using the ray-tracing code ‘LHDGauss’, which was upgraded to include the rapid post-processing three-dimensional (3D) equilibrium mapping obtained from experiments. For ray-tracing calculations, LHDGauss can automatically read the relevant data registered in the LHD database after a discharge, such as ECH injection settings (e.g. Gaussian beam parameters, target positions, polarisation and ECH power) and Thomson scattering diagnostic data along with the 3D equilibrium mapping data. The equilibrium map of the electron density and temperature profiles are then extrapolated into the region outside the last closed flux surface. Mode purity, or the ratio between the ordinary mode and the extraordinary mode, is obtained by calculating the 1D full-wave equation along the direction of the rays from the antenna to the absorption target point. Using the virtual magnetic flux surfaces, the effects of the modelled density profiles and the magnetic shear at the peripheral region with a given polarisation are taken into account. Power deposition profiles calculated for each Thomson scattering measurement timing are registered in the LHD database. The adjustment of the injection settings for the desired deposition profile from the feedback provided on a shot-by-shot basis resulted in an effective experimental procedure.

  16. Influence of extremely low frequency, low energy electromagnetic fields and combined mechanical stimulation on chondrocytes in 3-D constructs for cartilage tissue engineering.

    PubMed

    Hilz, Florian M; Ahrens, Philipp; Grad, Sibylle; Stoddart, Martin J; Dahmani, Chiheb; Wilken, Frauke L; Sauerschnig, Martin; Niemeyer, Philipp; Zwingmann, Jörn; Burgkart, Rainer; von Eisenhart-Rothe, Rüdiger; Südkamp, Norbert P; Weyh, Thomas; Imhoff, Andreas B; Alini, Mauro; Salzmann, Gian M

    2014-02-01

    Articular cartilage, once damaged, has very low regenerative potential. Various experimental approaches have been conducted to enhance chondrogenesis and cartilage maturation. Among those, non-invasive electromagnetic fields have shown their beneficial influence for cartilage regeneration and are widely used for the treatment of non-unions, fractures, avascular necrosis and osteoarthritis. One very well accepted way to promote cartilage maturation is physical stimulation through bioreactors. The aim of this study was the investigation of combined mechanical and electromagnetic stress affecting cartilage cells in vitro. Primary articular chondrocytes from bovine fetlock joints were seeded into three-dimensional (3-D) polyurethane scaffolds and distributed into seven stimulated experimental groups. They either underwent mechanical or electromagnetic stimulation (sinusoidal electromagnetic field of 1 mT, 2 mT, or 3 mT; 60 Hz) or both within a joint-specific bioreactor and a coil system. The scaffold-cell constructs were analyzed for glycosaminoglycan (GAG) and DNA content, histology, and gene expression of collagen-1, collagen-2, aggrecan, cartilage oligomeric matrix protein (COMP), Sox9, proteoglycan-4 (PRG-4), and matrix metalloproteinases (MMP-3 and -13). There were statistically significant differences in GAG/DNA content between the stimulated versus the control group with highest levels in the combined stimulation group. Gene expression was significantly higher for combined stimulation groups versus static control for collagen 2/collagen 1 ratio and lower for MMP-13. Amongst other genes, a more chondrogenic phenotype was noticed in expression patterns for the stimulated groups. To conclude, there is an effect of electromagnetic and mechanical stimulation on chondrocytes seeded in a 3-D scaffold, resulting in improved extracellular matrix production.

  17. Development of a 3D Electromagnetic Model for Eddy Current Tubing Inspection: Application to Steam Generator Tubing

    SciTech Connect

    Pichenot, G.; Premel, D.; Sollier, T.; Maillot, V.

    2004-02-26

    In nuclear plants, the inspection of heat exchanger tubes is usually carried out by using eddy current nondestructive testing. A numerical model, based on a volume integral approach using the Green's dyadic formalism, has been developed, with support from the French Institute for Radiological Protection and Nuclear Safety, to predict the response of an eddy current bobbin coil to 3D flaws located in the tube's wall. With an aim of integrating this model into the NDE multi techniques platform CIVA, it has been validated with experimental data for 2D and 3D flaws.

  18. Application of the Finite Orbit Width Version of the CQL3D Code to NBI +RF Heating of NSTX Plasma

    NASA Astrophysics Data System (ADS)

    Petrov, Yu. V.; Harvey, R. W.

    2015-11-01

    The CQL3D bounce-averaged Fokker-Planck (FP) code has been upgraded to include Finite-Orbit-Width (FOW) effects. The calculations can be done either with a fast Hybrid-FOW option or with a slower but neoclassically complete full-FOW option. The banana regime neoclassical radial transport appears naturally in the full-FOW version by averaging the local collision coefficients along guiding center orbits, with a proper transformation matrix from local (R, Z) coordinates to the midplane computational coordinates, where the FP equation is solved. In a similar way, the local quasilinear rf diffusion terms give rise to additional radial transport of orbits. The full-FOW version is applied to simulation of ion heating in NSTX plasma. It is demonstrated that it can describe the physics of transport phenomena in plasma with auxiliary heating, in particular, the enhancement of the radial transport of ions by RF heating and the occurrence of the bootstrap current. Because of the bounce-averaging on the FPE, the results are obtained in a relatively short computational time. A typical full-FOW run time is 30 min using 140 MPI cores. Due to an implicit solver, calculations with a large time step (tested up to dt = 0.5 sec) remain stable. Supported by USDOE grants SC0006614, ER54744, and ER44649.

  19. Implementation of a 3D version of ponderomotive guiding center solver in particle-in-cell code OSIRIS

    NASA Astrophysics Data System (ADS)

    Helm, Anton; Vieira, Jorge; Silva, Luis; Fonseca, Ricardo

    2016-10-01

    Laser-driven accelerators gained an increased attention over the past decades. Typical modeling techniques for laser wakefield acceleration (LWFA) are based on particle-in-cell (PIC) simulations. PIC simulations, however, are very computationally expensive due to the disparity of the relevant scales ranging from the laser wavelength, in the micrometer range, to the acceleration length, currently beyond the ten centimeter range. To minimize the gap between these despair scales the ponderomotive guiding center (PGC) algorithm is a promising approach. By describing the evolution of the laser pulse envelope separately, only the scales larger than the plasma wavelength are required to be resolved in the PGC algorithm, leading to speedups in several orders of magnitude. Previous work was limited to two dimensions. Here we present the implementation of the 3D version of a PGC solver into the massively parallel, fully relativistic PIC code OSIRIS. We extended the solver to include periodic boundary conditions and parallelization in all spatial dimensions. We present benchmarks for distributed and shared memory parallelization. We also discuss the stability of the PGC solver.

  20. The calculation of static polarizabilities of 1-3D periodic compounds. the implementation in the crystal code.

    PubMed

    Ferrero, Mauro; Rérat, Michel; Orlando, Roberto; Dovesi, Roberto

    2008-07-15

    The Coupled Perturbed Hartree-Fock (CPHF) scheme has been implemented in the CRYSTAL06 program, that uses a gaussian type basis set, for systems periodic in 1D (polymers), 2D (slabs), 3D (crystals) and, as a limiting case, 0D (molecules), which enables comparison with molecular codes. CPHF is applied to the calculation of the polarizability alpha of LiF in different aggregation states: finite and infinite chains, slabs, and cubic crystal. Correctness of the computational scheme for the various dimensionalities and its numerical efficiency are confirmed by the correct trend of alpha: alpha for a finite linear chain containing N LiF units with large N tends to the value for the infinite chain, N parallel chains give the slab value when N is sufficiently large, and N superimposed slabs tend to the bulk value. CPHF results compare well with those obtained with a saw-tooth potential approach, previously implemented in CRYSTAL. High numerical accuracy can easily be achieved at relatively low cost, with the same kind of dependence on the computational parameters as for the SCF cycle. Overall, the cost of one component of the dielectric tensor is roughly the same as for the SCF cycle, and it is dominated by the calculation of two-electron four-center integrals.

  1. DYNA3D: A nonlinear, explicit, three-dimensional finite element code for solid and structural mechanics, User manual. Revision 1

    SciTech Connect

    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.

  2. Comparison of the Aerospace Systems Test Reactor loss-of-coolant test data with predictions of the 3D-AIRLOCA code

    SciTech Connect

    Warinner, D.K.

    1983-01-01

    This paper compares the predictions of the revised 3D-AIRLOCA computer code to those data available from the Aerospace Systems Test Reactor's (ASTR's) loss-of-coolant-accident (LOCA) tests run in 1964. The theoretical and experimental hot-spot temperature responses compare remarkably well. In the thirteen cases studied, the irradiation powers varied from 0.4 to 8.87 MW; the irradiation times were 300, 1540, 1800, and 10/sup 4/ s. The degrees of agreement between the data and predictions provide an experimental validation of the 3D-AIRLOCA code.

  3. Kinetic description of the 3D electromagnetic structures formation in flows of expanding plasma coronas. Part 1: General

    NASA Astrophysics Data System (ADS)

    Gubchenko, V. M.

    2015-12-01

    In part I of the work, the physical effects responsible for the formation of low-speed flows in plasma coronas, coupled with formation of coronas magnetosphere-like structures, are described qualitatively. Coronal domain structures form if we neglect scales of spatial plasma dispersion: high-speed flows are accumulated in magnetic tubes of the open domains, while magnetic structures and low-speed flows are concentrated within boundaries of domains. The inductive electromagnetic process occurring in flows of the hot collisionless plasma is shown to underlie the formation of magnetosphere-like structures. Depending on the form of the velocity distribution function of particles (PDF), a hot flow differently reveals its electromagnetic properties, which are expressed by the induction of resistive and diamagnetic scales of spatial dispersion. These determine the magnetic structure scales and structure reconstruction. The inductive electromagnetic process located in lines of the plasma nontransparency and absorption, in which the structures of excited fields are spatially aperiodic and skinned to the magnetic field sources. The toroidal and dipole magnetic sources of different configurations are considered for describing the corona structures during the solar maximum and solar minimum.

  4. TFaNS Tone Fan Noise Design/Prediction System. Volume 1; System Description, CUP3D Technical Documentation and Manual for Code Developers

    NASA Technical Reports Server (NTRS)

    Topol, David A.

    1999-01-01

    TFaNS is the Tone Fan Noise Design/Prediction System developed by Pratt & Whitney under contract to NASA Lewis (presently NASA Glenn). The purpose of this system is to predict tone noise emanating from a fan stage including the effects of reflection and transmission by the rotor and stator and by the duct inlet and nozzle. These effects have been added to an existing annular duct/isolated stator noise prediction capability. TFaNS consists of: The codes that compute the acoustic properties (reflection and transmission coefficients) of the various elements and write them to files. Cup3D: Fan Noise Coupling Code that reads these files, solves the coupling problem, and outputs the desired noise predictions. AWAKEN: CFD/Measured Wake Postprocessor which reformats CFD wake predictions and/or measured wake data so it can be used by the system. This volume of the report provides technical background for TFaNS including the organization of the system and CUP3D technical documentation. This document also provides information for code developers who must write Acoustic Property Files in the CUP3D format. This report is divided into three volumes: Volume I: System Description, CUP3D Technical Documentation, and Manual for Code Developers; Volume II: User's Manual, TFaNS Vers. 1.4; Volume III: Evaluation of System Codes.

  5. Electromagnetic coupling and array packing induce exchange of dominance on complex modes in 3D periodic arrays of spheres with large permittivity

    SciTech Connect

    Campione, Salvatore; Capolino, Filippo

    2016-01-25

    In this study, we investigate the effect on wave propagation of array packing and electromagnetic coupling between spheres in a three-dimensional (3D) lattice of microspheres with large permittivity that exhibit strong magnetic polarizability. We report on the complex wavenumber of Bloch waves in the lattice when each sphere is assumed to possess both electric and magnetic dipoles and full electromagnetic coupling is accounted for. While for small material-filling fractions we always determine one dominant mode with low attenuation constant, the same does not happen for large filling fractions, when electromagnetic coupling is included. In the latter case we peculiarly observe two dominant modes with low attenuation constant, dominant in different frequency ranges. The filling fraction threshold for which two dominant modes appear varies for different metamaterial constituents, as proven by considering spheres made by either titanium dioxide or lead telluride. As further confirmation of our findings, we retrieve the complex propagation constant of the dominant mode(s) via a field fitting procedure employing two sets of waves (direct and reflected) pertaining to two distinct modes, strengthening the presence of the two distinct dominant modes for increasing filling fractions. However, given that one mode only, with transverse polarization, at any given frequency, is dominant and able to propagate inside the lattice, we are able to accurately treat the metamaterial that is known to exhibit artificial magnetism as a homogeneous material with effective parameters, such as the refractive index. Results clearly show that the account of both electric and magnetic scattering processes in evaluating all electromagnetic intersphere couplings is essential for a proper description of the electromagnetic propagation in lattices.

  6. Electromagnetic coupling and array packing induce exchange of dominance on complex modes in 3D periodic arrays of spheres with large permittivity

    DOE PAGES

    Campione, Salvatore; Capolino, Filippo

    2016-01-25

    In this study, we investigate the effect on wave propagation of array packing and electromagnetic coupling between spheres in a three-dimensional (3D) lattice of microspheres with large permittivity that exhibit strong magnetic polarizability. We report on the complex wavenumber of Bloch waves in the lattice when each sphere is assumed to possess both electric and magnetic dipoles and full electromagnetic coupling is accounted for. While for small material-filling fractions we always determine one dominant mode with low attenuation constant, the same does not happen for large filling fractions, when electromagnetic coupling is included. In the latter case we peculiarly observemore » two dominant modes with low attenuation constant, dominant in different frequency ranges. The filling fraction threshold for which two dominant modes appear varies for different metamaterial constituents, as proven by considering spheres made by either titanium dioxide or lead telluride. As further confirmation of our findings, we retrieve the complex propagation constant of the dominant mode(s) via a field fitting procedure employing two sets of waves (direct and reflected) pertaining to two distinct modes, strengthening the presence of the two distinct dominant modes for increasing filling fractions. However, given that one mode only, with transverse polarization, at any given frequency, is dominant and able to propagate inside the lattice, we are able to accurately treat the metamaterial that is known to exhibit artificial magnetism as a homogeneous material with effective parameters, such as the refractive index. Results clearly show that the account of both electric and magnetic scattering processes in evaluating all electromagnetic intersphere couplings is essential for a proper description of the electromagnetic propagation in lattices.« less

  7. Test Problems for Reactive Flow HE Model in the ALE3D Code and Limited Sensitivity Study

    SciTech Connect

    Gerassimenko, M.

    2000-03-01

    We document quick running test problems for a reactive flow model of HE initiation incorporated into ALE3D. A quarter percent change in projectile velocity changes the outcome from detonation to HE burn that dies down. We study the sensitivity of calculated HE behavior to several parameters of practical interest where modeling HE initiation with ALE3D.

  8. A multiblock/multizone code (PAB 3D-v2) for the three-dimensional Navier-Stokes equations: Preliminary applications

    NASA Technical Reports Server (NTRS)

    Abdol-Hamid, Khaled S.

    1990-01-01

    The development and applications of multiblock/multizone and adaptive grid methodologies for solving the three-dimensional simplified Navier-Stokes equations are described. Adaptive grid and multiblock/multizone approaches are introduced and applied to external and internal flow problems. These new implementations increase the capabilities and flexibility of the PAB3D code in solving flow problems associated with complex geometry.

  9. Mechanical, Electromagnetic, and X-ray Shielding Characterization of a 3D Printable Tungsten-Polycarbonate Polymer Matrix Composite for Space-Based Applications

    NASA Astrophysics Data System (ADS)

    Shemelya, Corey M.; Rivera, Armando; Perez, Angel Torrado; Rocha, Carmen; Liang, Min; Yu, Xiaoju; Kief, Craig; Alexander, David; Stegeman, James; Xin, Hao; Wicker, Ryan B.; MacDonald, Eric; Roberson, David A.

    2015-08-01

    Material-extrusion three-dimensional (3D) printing has recently attracted much interest because of its process flexibility, rapid response to design alterations, and ability to create structures "on-the-go". For this reason, 3D printing has possible applications in rapid creation of space-based devices, for example cube satellites (CubeSat). This work focused on fabrication and characterization of tungsten-doped polycarbonate polymer matrix composites specifically designed for x-ray radiation-shielding applications. The polycarbonate-tungsten polymer composite obtained intentionally utilizes low loading levels to provide x-ray shielding while limiting effects on other properties of the material, for example weight, electromagnetic functionality, and mechanical strength. The fabrication process, from tungsten functionalization to filament extrusion and material characterization, is described, including printability, determination of x-ray attenuation, tensile strength, impact resistance, and gigahertz permittivity, and failure analysis. The proposed materials are uniquely advantageous when implemented in 3D printed structures, because even a small volume fraction of tungsten has been shown to substantially alter the properties of the resulting composite.

  10. New results on the resistivity structure of Merapi Volcano(Indonesia), derived from 3D restricted inversion of long-offsettransient electromagnetic data

    SciTech Connect

    Commer, Michael; Helwig, Stefan, L.; Hordt, Andreas; Scholl,Carsten; Tezkan, Bulent

    2006-06-14

    Three long-offset transient electromagnetic (LOTEM) surveyswerecarried out at the active volcano Merapi in Central Java (Indonesia)during the years 1998, 2000, and 2001. The measurements focused on thegeneral resistivity structure of the volcanic edifice at depths of 0.5-2km and the further investigation of a southside anomaly. The measurementswere insufficient for a full 3D inversion scheme, which could enable theimaging of finely discretized resistivity distributions. Therefore, astable, damped least-squares joint-inversion approach is used to optimize3D models with a limited number of parameters. The mode ls feature therealistic simulation of topography, a layered background structure, andadditional coarse 3D blocks representing conductivity anomalies.Twenty-eight LOTEM transients, comprising both horizontal and verticalcomponents of the magnetic induction time derivative, were analyzed. Inview of the few unknowns, we were able to achieve reasonable data fits.The inversion results indicate an upwelling conductor below the summit,suggesting hydrothermal activity in the central volcanic complex. Ashallow conductor due to a magma-filled chamber, at depths down to 1 kmbelow the summit, suggested by earlier seismic studies, is not indicatedby the inversion results. In conjunction with an anomalous-density model,derived from arecent gravity study, our inversion results provideinformation about the southern geological structure resulting from amajor sector collapse during the Middle Merapi period. The density modelallows to assess a porosity range andthus an estimated vertical salinityprofile to explain the high conductivities on a larger scale, extendingbeyond the foothills of Merapi.

  11. Numerical model of water flow and solute accumulation in vertisols using HYDRUS 2D/3D code

    NASA Astrophysics Data System (ADS)

    Weiss, Tomáš; Dahan, Ofer; Turkeltub, Tuvia

    2015-04-01

    boundary to the wall of the crack (so that the solute can accumulate due to evaporation on the crack block wall, and infiltrating fresh water can push the solute further down) - in order to do so, HYDRUS 2D/3D code had to be modified by its developers. Unconventionally, the main fitting parameters were: parameter a and n in the soil water retention curve and saturated hydraulic conductivity. The amount of infiltrated water (within a reasonable range), the infiltration function in the crack and the actual evaporation from the crack were also used as secondary fitting parameters. The model supports the previous findings that significant amount (~90%) of water from rain events must infiltrate through the crack. It was also noted that infiltration from the crack has to be increasing with depth and that the highest infiltration rate should be somewhere between 1-3m. This paper suggests a new way how to model vertisols in semi-arid regions. It also supports the previous findings about vertisols: especially, the utmost importance of soil cracks as preferential pathways for water and contaminants and soil cracks as deep evaporators.

  12. A finite-difference frequency-domain code for electromagnetic induction tomography

    SciTech Connect

    Sharpe, R M; Berryman, J G; Buettner, H M; Champagne, N J.,II; Grant, J B

    1998-12-17

    We are developing a new 3D code for application to electromagnetic induction tomography and applications to environmental imaging problems. We have used the finite-difference frequency- domain formulation of Beilenhoff et al. (1992) and the anisotropic PML (perfectly matched layer) approach (Berenger, 1994) to specify boundary conditions following Wu et al. (1997). PML deals with the fact that the computations must be done in a finite domain even though the real problem is effectively of infinite extent. The resulting formulas for the forward solver reduce to a problem of the form Ax = y, where A is a non-Hermitian matrix with real values off the diagonal and complex values along its diagonal. The matrix A may be either symmetric or nonsymmetric depending on details of the boundary conditions chosen (i.e., the particular PML used in the application). The basic equation must be solved for the vector x (which represents field quantities such as electric and magnetic fields) with the vector y determined by the boundary conditions and transmitter location. Of the many forward solvers that could be used for this system, relatively few have been thoroughly tested for the type of matrix encountered in our problem. Our studies of the stability characteristics of the Bi-CG algorithm raised questions about its reliability and uniform accuracy for this application. We have found the stability characteristics of Bi-CGSTAB [an alternative developed by van der Vorst (1992) for such problems] to be entirely adequate for our application, whereas the standard Bi-CG was quite inadequate. We have also done extensive validation of our code using semianalytical results as well as other codes. The new code is written in Fortran and is designed to be easily parallelized, but we have not yet tested this feature of the code. An adjoint method is being developed for solving the inverse problem for conductivity imaging (for mapping underground plumes), and this approach, when ready, will

  13. A new efficient 3D Discontinuous Galerkin Time Domain (DGTD) method for large and multiscale electromagnetic simulations

    NASA Astrophysics Data System (ADS)

    Tobón, Luis E.; Ren, Qiang; Liu, Qing Huo

    2015-02-01

    A new Discontinuous Galerkin Time Domain (DGTD) method for solving the 3D time dependent Maxwell's equations via the electric field intensity E and magnetic flux density B fields is proposed for the first time. It uses curl-conforming and divergence-conforming basis functions for E and B, respectively, with the same order of interpolation. In this way, higher accuracy is achieved at lower memory consumption than the conventional approach based on the field variables E and H. The centered flux and Riemann solver are both used to treat interfaces with non-conforming meshes, and both explicit Runge-Kutta method and implicit Crank-Nicholson method are implemented for time integration. Numerical examples for realistic cases will be presented to verify that the proposed method is a non-spurious and efficient DGTD scheme.

  14. NIKE3D: an implicit, finite-deformation, finite element code for analyzing the static and dynamic response of three-dimensional solids

    SciTech Connect

    Hallquist, J.O.

    1981-01-01

    A user's manual is provided for NIKE3D, a fully implicit three-dimensional finite element code for analyzing the large deformation static and dynamic response of inelastic solids. A contact-impact algorithm permits gaps and sliding along material interfaces. By a specialization of this algorithm, such interfaces can be rigidly tied to admit variable zoning without the need of transition regions. Spatial discretization is achieved by the use of 8-node constant pressure solid elements. Bandwidth minimization is optional. Post-processors for NIKE3D include GRAPE for plotting deformed shapes and stress contours and DYNAP for plotting time histories.

  15. TART 2000: A Coupled Neutron-Photon, 3-D, Combinatorial Geometry, Time Dependent, Monte Carlo Transport Code

    SciTech Connect

    Cullen, D.E

    2000-11-22

    TART2000 is a coupled neutron-photon, 3 Dimensional, combinatorial geometry, time dependent Monte Carlo radiation transport code. This code can run on any modern computer. It is a complete system to assist you with input Preparation, running Monte Carlo calculations, and analysis of output results. TART2000 is also incredibly FAST; if you have used similar codes, you will be amazed at how fast this code is compared to other similar codes. Use of the entire system can save you a great deal of time and energy. TART2000 is distributed on CD. This CD contains on-line documentation for all codes included in the system, the codes configured to run on a variety of computers, and many example problems that you can use to familiarize yourself with the system. TART2000 completely supersedes all older versions of TART, and it is strongly recommended that users only use the most recent version of TART2000 and its data files.

  16. TART98 a coupled neutron-photon 3-D, combinatorial geometry time dependent Monte Carlo Transport code

    SciTech Connect

    Cullen, D E

    1998-11-22

    TART98 is a coupled neutron-photon, 3 Dimensional, combinatorial geometry, time dependent Monte Carlo radiation transport code. This code can run on any modern computer. It is a complete system to assist you with input preparation, running Monte Carlo calculations, and analysis of output results. TART98 is also incredibly FAST; if you have used similar codes, you will be amazed at how fast this code is compared to other similar codes. Use of the entire system can save you a great deal of time and energy. TART98 is distributed on CD. This CD contains on-line documentation for all codes included in the system, the codes configured to run on a variety of computers, and many example problems that you can use to familiarize yourself with the system. TART98 completely supersedes all older versions of TART, and it is strongly recommended that users only use the most recent version of TART98 and its data files.

  17. Towards a fully kinetic 3D electromagnetic particle-in-cell model of streamer formation and dynamics in high-pressure electronegative gases

    NASA Astrophysics Data System (ADS)

    Rose, D. V.; Welch, D. R.; Clark, R. E.; Thoma, C.; Zimmerman, W. R.; Bruner, N.; Rambo, P. K.; Atherton, B. W.

    2011-09-01

    Streamer and leader formation in high pressure devices is dynamic process involving a broad range of physical phenomena. These include elastic and inelastic particle collisions in the gas, radiation generation, transport and absorption, and electrode interactions. Accurate modeling of these physical processes is essential for a number of applications, including high-current, laser-triggered gas switches. Towards this end, we present a new 3D implicit particle-in-cell simulation model of gas breakdown leading to streamer formation in electronegative gases. The model uses a Monte Carlo treatment for all particle interactions and includes discrete photon generation, transport, and absorption for ultra-violet and soft x-ray radiation. Central to the realization of this fully kinetic particle treatment is an algorithm that manages the total particle count by species while preserving the local momentum distribution functions and conserving charge [D. R. Welch, T. C. Genoni, R. E. Clark, and D. V. Rose, J. Comput. Phys. 227, 143 (2007)]. The simulation model is fully electromagnetic, making it capable of following, for example, the evolution of a gas switch from the point of laser-induced localized breakdown of the gas between electrodes through the successive stages of streamer propagation, initial electrode current connection, and high-current conduction channel evolution, where self-magnetic field effects are likely to be important. We describe the model details and underlying assumptions used and present sample results from 3D simulations of streamer formation and propagation in SF6.

  18. Combination of electromagnetic, geophysical methods and sedimentological studies for the development of 3D models in alluvial sediments affected by karst (Ebro Basin, NE Spain)

    NASA Astrophysics Data System (ADS)

    Pueyo Anchuela, Óscar; Luzón, Aránzazu; Gil Garbi, Héctor; Pérez, Antonio; Pocoví Juan, Andrés; Soriano, María Asunción

    2014-03-01

    An integrated analysis was carried out in a selected quarry of the oldest terrace of the Ebro River, where a wide gravel unit is characterized by large-scale cross bedding outcrops. This unit has been interpreted as a lake with marginal deltas. Previous sedimentological studies have pointed out that braided rivers have dominated in the area during the Early Pleistocene. The presence of a lake, which in stable conditions (without subsidence) could be hardly developed in a braided fluvial setting, supports that a topographic depression pre-existed. The delta gravels suggest a depth of at least 5 m for this depression. Established models from broadband multifrequency electromagnetic survey and ground penetrating radar (GPR) show that the analyzed area was affected by a long-term karstic subsidence, which generated a doline field in which topographic depressions were filled by marls and marginal gravels, and subsequently affected by minor collapses during different subsidence reactivation episodes. A 3D model of the evolution and meaning of the doline field and its interaction with sedimentation has been developed. This model can be applied in other areas where high-resolution geophysical 3D models are difficult to establish because of the limitations of the geophysical surveys due to the presence of interbedded mudstones, subsiding depressions filled by human activities or near surface water levels.

  19. A two-level space-time color-coding method for 3D measurements using structured light

    NASA Astrophysics Data System (ADS)

    Xue, Qi; Wang, Zhao; Huang, Junhui; Gao, Jianmin; Qi, Zhaoshuai

    2015-11-01

    Color-coding methods have significantly improved the measurement efficiency of structured light systems. However, some problems, such as color crosstalk and chromatic aberration, decrease the measurement accuracy of the system. A two-level space-time color-coding method is thus proposed in this paper. The method, which includes a space-code level and a time-code level, is shown to be reliable and efficient. The influence of chromatic aberration is completely mitigated when using this method. Additionally, a self-adaptive windowed Fourier transform is used to eliminate all color crosstalk components. Theoretical analyses and experiments have shown that the proposed coding method solves the problems of color crosstalk and chromatic aberration effectively. Additionally, the method guarantees high measurement accuracy which is very close to the measurement accuracy using monochromatic coded patterns.

  20. Neural coding of 3D features of objects for hand action in the parietal cortex of the monkey.

    PubMed Central

    Sakata, H; Taira, M; Kusunoki, M; Murata, A; Tanaka, Y; Tsutsui, K

    1998-01-01

    In our previous studies of hand manipulation task-related neurons, we found many neurons of the parietal association cortex which responded to the sight of three-dimensional (3D) objects. Most of the task-related neurons in the AIP area (the lateral bank of the anterior intraparietal sulcus) were visually responsive and half of them responded to objects for manipulation. Most of these neurons were selective for the 3D features of the objects. More recently, we have found binocular visual neurons in the lateral bank of the caudal intraparietal sulcus (c-IPS area) that preferentially respond to a luminous bar or place at a particular orientation in space. We studied the responses of axis-orientation selective (AOS) neurons and surface-orientation selective (SOS) neurons in this area with stimuli presented on a 3D computer graphics display. The AOS neurons showed a stronger response to elongated stimuli and showed tuning to the orientation of the longitudinal axis. Many of them preferred a tilted stimulus in depth and appeared to be sensitive to orientation disparity and/or width disparity. The SOS neurons showed a stronger response to a flat than to an elongated stimulus and showed tuning to the 3D orientation of the surface. Their responses increased with the width or length of the stimulus. A considerable number of SOS neurons responded to a square in a random dot stereogram and were tuned to orientation in depth, suggesting their sensitivity to the gradient of disparity. We also found several SOS neurons that responded to a square with tilted or slanted contours, suggesting their sensitivity to orientation disparity and/or width disparity. Area c-IPS is likely to send visual signals of the 3D features of an object to area AIP for the visual guidance of hand actions. PMID:9770229

  1. T-Matrix: Codes for Computing Electromagnetic Scattering by Nonspherical and Aggregated Particles

    NASA Astrophysics Data System (ADS)

    Waterman, Peter; Mishchenko, Michael I.; Travis, Larry D.; Mackowski, Daniel W.

    2015-11-01

    The T-Matrix package includes codes to compute electromagnetic scattering by homogeneous, rotationally symmetric nonspherical particles in fixed and random orientations, randomly oriented two-sphere clusters with touching or separated components, and multi-sphere clusters in fixed and random orientations. All codes are written in Fortran-77. LAPACK-based, extended-precision, Gauss-elimination- and NAG-based, and superposition codes are available, as are double-precision superposition, parallelized double-precision, double-precision Lorenz-Mie codes, and codes for the computation of the coefficients for the generalized Chebyshev shape.

  2. A new type of color-coded light structures for an adapted and rapid determination of point correspondences for 3D reconstruction

    NASA Astrophysics Data System (ADS)

    Caulier, Yannick; Bernhard, Luc; Spinnler, Klaus

    2011-05-01

    This paper proposes a new type of color coded light structures for the inspection of complex moving objects. The novelty of the methods relies on the generation of free-form color patterns permitting the projection of color structures adapted to the geometry of the surfaces to be characterized. The point correspondence determination algorithm consists of a stepwise procedure involving simple and computationally fast methods. The algorithm is therefore robust against varying recording conditions typically arising in real-time quality control environments and can be further integrated for industrial inspection purposes. The proposed approach is validated and compared on the basis of different experimentations concerning the 3D surface reconstruction by projecting adapted spatial color coded patterns. It is demonstrated that in case of certain inspection requirements, the method permits to code more reference points that similar color coded matrix methods.

  3. Application of the RNS3D Code to a Circular-Rectangular Transition Duct With and Without Inlet Swirl and Comparison with Experiments

    NASA Technical Reports Server (NTRS)

    Cavicchi, Richard H.

    1999-01-01

    Circular-rectangular transition ducts are used between engine exhausts and nozzles with rectangular cross sections that are designed for high performance aircraft. NASA Glenn Research Center has made experimental investigations of a series of circular-rectangular transition ducts to provide benchmark flow data for comparison with numerical calculations. These ducts are all designed with superellipse cross sections to facilitate grid generation. In response to this challenge, the three-dimensional RNS3D code has been applied to one of these transition ducts. This particular duct has a length-to-inlet diameter ratio of 1.5 and an exit-plane aspect ratio of 3.0. The inlet Mach number is 0.35. Two GRC experiments and the code were run for this duct without inlet swirl. One GRC experiment and the code were also run with inlet swirl. With no inlet swirl the code was successful in predicting pressures and secondary flow conditions, including a pair of counter-rotating vortices at both sidewalls of the exit plane. All these phenomena have been reported from the two GRC experiments. However, these vortices were suppressed in the one experiment when inlet swirl was used; whereas the RNS3D code still predicted them. The experiment was unable to provide data near the sidewalls, the very region where the vortices were predicted.

  4. SummitView 1.0: a code to automatically generate 3D solid models of surface micro-machining based MEMS designs.

    SciTech Connect

    McBride, Cory L. (Elemental Technologies, American Fort, UT); Yarberry, Victor R.; Schmidt, Rodney Cannon; Meyers, Ray J.

    2006-11-01

    This report describes the SummitView 1.0 computer code developed at Sandia National Laboratories. SummitView is designed to generate a 3D solid model, amenable to visualization and meshing, that represents the end state of a microsystem fabrication process such as the SUMMiT (Sandia Ultra-Planar Multilevel MEMS Technology) V process. Functionally, SummitView performs essentially the same computational task as an earlier code called the 3D Geometry modeler [1]. However, because SummitView is based on 2D instead of 3D data structures and operations, it has significant speed and robustness advantages. As input it requires a definition of both the process itself and the collection of individual 2D masks created by the designer and associated with each of the process steps. The definition of the process is contained in a special process definition file [2] and the 2D masks are contained in MEM format files [3]. The code is written in C++ and consists of a set of classes and routines. The classes represent the geometric data and the SUMMiT V process steps. Classes are provided for the following process steps: Planar Deposition, Planar Etch, Conformal Deposition, Dry Etch, Wet Etch and Release Etch. SummitView is built upon the 2D Boolean library GBL-2D [4], and thus contains all of that library's functionality.

  5. Solwnd: A 3D Compressible MHD Code for Solar Wind Studies. Version 1.0: Cartesian Coordinates

    NASA Technical Reports Server (NTRS)

    Deane, Anil E.

    1996-01-01

    Solwnd 1.0 is a three-dimensional compressible MHD code written in Fortran for studying the solar wind. Time-dependent boundary conditions are available. The computational algorithm is based on Flux Corrected Transport and the code is based on the existing code of Zalesak and Spicer. The flow considered is that of shear flow with incoming flow that perturbs this base flow. Several test cases corresponding to pressure balanced magnetic structures with velocity shear flow and various inflows including Alfven waves are presented. Version 1.0 of solwnd considers a rectangular Cartesian geometry. Future versions of solwnd will consider a spherical geometry. Some discussions of this issue is presented.

  6. Analysis of the beam halo in negative ion sources by using 3D3V PIC code.

    PubMed

    Miyamoto, K; Nishioka, S; Goto, I; Hatayama, A; Hanada, M; Kojima, A; Hiratsuka, J

    2016-02-01

    The physical mechanism of the formation of the negative ion beam halo and the heat loads of the multi-stage acceleration grids are investigated with the 3D PIC (particle in cell) simulation. The following physical mechanism of the beam halo formation is verified: The beam core and the halo consist of the negative ions extracted from the center and the periphery of the meniscus, respectively. This difference of negative ion extraction location results in a geometrical aberration. Furthermore, it is shown that the heat loads on the first acceleration grid and the second acceleration grid are quantitatively improved compared with those for the 2D PIC simulation result.

  7. Analysis of the beam halo in negative ion sources by using 3D3V PIC code

    SciTech Connect

    Miyamoto, K.; Nishioka, S.; Goto, I.; Hatayama, A.; Hanada, M.; Kojima, A.; Hiratsuka, J.

    2016-02-15

    The physical mechanism of the formation of the negative ion beam halo and the heat loads of the multi-stage acceleration grids are investigated with the 3D PIC (particle in cell) simulation. The following physical mechanism of the beam halo formation is verified: The beam core and the halo consist of the negative ions extracted from the center and the periphery of the meniscus, respectively. This difference of negative ion extraction location results in a geometrical aberration. Furthermore, it is shown that the heat loads on the first acceleration grid and the second acceleration grid are quantitatively improved compared with those for the 2D PIC simulation result.

  8. FACET: a radiation view factor computer code for axisymmetric, 2D planar, and 3D geometries with shadowing

    SciTech Connect

    Shapiro, A.B.

    1983-08-01

    The computer code FACET calculates the radiation geometric view factor (alternatively called shape factor, angle factor, or configuration factor) between surfaces for axisymmetric, two-dimensional planar and three-dimensional geometries with interposed third surface obstructions. FACET was developed to calculate view factors for input to finite-element heat-transfer analysis codes. The first section of this report is a brief review of previous radiation-view-factor computer codes. The second section presents the defining integral equation for the geometric view factor between two surfaces and the assumptions made in its derivation. Also in this section are the numerical algorithms used to integrate this equation for the various geometries. The third section presents the algorithms used to detect self-shadowing and third-surface shadowing between the two surfaces for which a view factor is being calculated. The fourth section provides a user's input guide followed by several example problems.

  9. Estimation of aortic valve leaflets from 3D CT images using local shape dictionaries and linear coding

    NASA Astrophysics Data System (ADS)

    Liang, Liang; Martin, Caitlin; Wang, Qian; Sun, Wei; Duncan, James

    2016-03-01

    Aortic valve (AV) disease is a significant cause of morbidity and mortality. The preferred treatment modality for severe AV disease is surgical resection and replacement of the native valve with either a mechanical or tissue prosthetic. In order to develop effective and long-lasting treatment methods, computational analyses, e.g., structural finite element (FE) and computational fluid dynamic simulations, are very effective for studying valve biomechanics. These computational analyses are based on mesh models of the aortic valve, which are usually constructed from 3D CT images though many hours of manual annotation, and therefore an automatic valve shape reconstruction method is desired. In this paper, we present a method for estimating the aortic valve shape from 3D cardiac CT images, which is represented by triangle meshes. We propose a pipeline for aortic valve shape estimation which includes novel algorithms for building local shape dictionaries and for building landmark detectors and curve detectors using local shape dictionaries. The method is evaluated on real patient image dataset using a leave-one-out approach and achieves an average accuracy of 0.69 mm. The work will facilitate automatic patient-specific computational modeling of the aortic valve.

  10. Development of a 3D FEL code for the simulation of a high-gain harmonic generation experiment.

    SciTech Connect

    Biedron, S. G.

    1999-02-26

    Over the last few years, there has been a growing interest in self-amplified spontaneous emission (SASE) free-electron lasers (FELs) as a means for achieving a fourth-generation light source. In order to correctly and easily simulate the many configurations that have been suggested, such as multi-segmented wigglers and the method of high-gain harmonic generation, we have developed a robust three-dimensional code. The specifics of the code, the comparison to the linear theory as well as future plans will be presented.

  11. Mariage des maillages: A new 3D general relativistic hydro code for simulation of gravitational waves from core-collapses.

    NASA Astrophysics Data System (ADS)

    Novak, Jerome; Dimmelmeier, Harrald; Font-Roda, Jose A.

    2004-12-01

    We present a new three-dimensional general relativistic hydrodynamics code which can be applied to study stellar core collapses and the resulting gravitational radiation. This code uses two different numerical techniques to solve partial differential equations arising in the model: high-resolution shock capturing (HRSC) schemes for the evolution of hydrodynamic quantities and spectral methods for the solution of Einstein equations. The equations are written and solved using spherical polar coordinates, best suited to stellar topology. Einstein equations are formulated within the 3+1 formalism and conformal flat condition (CFC) for the 3-metric and gravitational radiation is extracted using Newtonian quadrupole formulation.

  12. NIKE3D a nonlinear, implicit, three-dimensional finite element code for solid and structural mechanics user's manual update summary

    SciTech Connect

    Puso, M; Maker, B N; Ferencz, R M; Hallquist, J O

    2000-03-24

    This report provides the NIKE3D user's manual update summary for changes made from version 3.0.0 April 24, 1995 to version 3.3.6 March 24,2000. The updates are excerpted directly from the code printed output file (hence the Courier font and formatting), are presented in chronological order and delineated by NIKE3D version number. NIKE3D is a fully implicit three-dimensional finite element code for analyzing the finite strain static and dynamic response of inelastic solids, shells, and beams. Spatial discretization is achieved by the use of 8-node solid elements, 2-node truss and beam elements, and 4-node membrane and shell elements. Thirty constitutive models are available for representing a wide range of elastic, plastic, viscous, and thermally dependent material behavior. Contact-impact algorithms permit gaps, frictional sliding, and mesh discontinuities along material interfaces. Several nonlinear solution strategies are available, including Full-, Modified-, and Quasi-Newton methods. The resulting system of simultaneous linear equations is either solved iteratively by an element-by-element method, or directly by a direct factorization method.

  13. Recent advances to NEC (Numerical Electromagnetics Code): Applications and validation

    SciTech Connect

    Burke, G.J. )

    1989-03-03

    Capabilities of the antenna modeling code NEC are reviewed and results are presented to illustrate typical applications. Recent developments are discussed that will improve accuracy in modeling electrically small antennas, stepped-radius wires and junctions of tightly coupled wires, and also a new capability for modeling insulated wires in air or earth is described. These advances will be included in a future release of NEC, while for now the results serve to illustrate limitations of the present code. NEC results are compared with independent analytical and numerical solutions and measurements to validate the model for wires near ground and for insulated wires. 41 refs., 26 figs., 1 tab.

  14. WE-A-17A-10: Fast, Automatic and Accurate Catheter Reconstruction in HDR Brachytherapy Using An Electromagnetic 3D Tracking System

    SciTech Connect

    Poulin, E; Racine, E; Beaulieu, L; Binnekamp, D

    2014-06-15

    Purpose: In high dose rate brachytherapy (HDR-B), actual catheter reconstruction protocols are slow and errors prompt. The purpose of this study was to evaluate the accuracy and robustness of an electromagnetic (EM) tracking system for improved catheter reconstruction in HDR-B protocols. Methods: For this proof-of-principle, a total of 10 catheters were inserted in gelatin phantoms with different trajectories. Catheters were reconstructed using a Philips-design 18G biopsy needle (used as an EM stylet) and the second generation Aurora Planar Field Generator from Northern Digital Inc. The Aurora EM system exploits alternating current technology and generates 3D points at 40 Hz. Phantoms were also scanned using a μCT (GE Healthcare) and Philips Big Bore clinical CT system with a resolution of 0.089 mm and 2 mm, respectively. Reconstructions using the EM stylet were compared to μCT and CT. To assess the robustness of the EM reconstruction, 5 catheters were reconstructed twice and compared. Results: Reconstruction time for one catheter was 10 seconds or less. This would imply that for a typical clinical implant of 17 catheters, the total reconstruction time would be less than 3 minutes. When compared to the μCT, the mean EM tip identification error was 0.69 ± 0.29 mm while the CT error was 1.08 ± 0.67 mm. The mean 3D distance error was found to be 0.92 ± 0.37 mm and 1.74 ± 1.39 mm for the EM and CT, respectively. EM 3D catheter trajectories were found to be significantly more accurate (unpaired t-test, p < 0.05). A mean difference of less than 0.5 mm was found between successive EM reconstructions. Conclusion: The EM reconstruction was found to be faster, more accurate and more robust than the conventional methods used for catheter reconstruction in HDR-B. This approach can be applied to any type of catheters and applicators. We would like to disclose that the equipments, used in this study, is coming from a collaboration with Philips Medical.

  15. An open-source Matlab code package for improved rank-reduction 3D seismic data denoising and reconstruction

    NASA Astrophysics Data System (ADS)

    Chen, Yangkang; Huang, Weilin; Zhang, Dong; Chen, Wei

    2016-10-01

    Simultaneous seismic data denoising and reconstruction is a currently popular research subject in modern reflection seismology. Traditional rank-reduction based 3D seismic data denoising and reconstruction algorithm will cause strong residual noise in the reconstructed data and thus affect the following processing and interpretation tasks. In this paper, we propose an improved rank-reduction method by modifying the truncated singular value decomposition (TSVD) formula used in the traditional method. The proposed approach can help us obtain nearly perfect reconstruction performance even in the case of low signal-to-noise ratio (SNR). The proposed algorithm is tested via one synthetic and field data examples. Considering that seismic data interpolation and denoising source packages are seldom in the public domain, we also provide a program template for the rank-reduction based simultaneous denoising and reconstruction algorithm by providing an open-source Matlab package.

  16. Time-Dependent Distribution Functions in C-Mod Calculated with the CQL3D-Hybrid-FOW, AORSA Full-Wave, and DC Lorentz Codes

    NASA Astrophysics Data System (ADS)

    Harvey, R. W. (Bob); Petrov, Yu. V.; Jaeger, E. F.; Berry, L. A.; Bonoli, P. T.; Bader, A.

    2015-11-01

    A time-dependent simulation of C-Mod pulsed ICRF power is made calculating minority hydrogen ion distribution functions with the CQL3D-Hybrid-FOW finite-orbit-width Fokker-Planck code. ICRF fields are calculated with the AORSA full wave code, and RF diffusion coefficients are obtained from these fields using the DC Lorentz gyro-orbit code. Prior results with a zero-banana-width simulation using the CQL3D/AORSA/DC time-cycles showed a pronounced enhancement of the H distribution in the perpendicular velocity direction compared to results obtained from Stix's quasilinear theory, in general agreement with experiment. The present study compares the new FOW results, including relevant gyro-radius effects, to determine the importance of these effects on the the NPA synthetic diagnostic time-dependence. The new NPA results give increased agreement with experiment, particularly in the ramp-down time after the ICRF pulse. Funded, through subcontract with Massachusetts Institute of Technology, by USDOE sponsored SciDAC Center for Simulation of Wave-Plasma Interactions.

  17. Revisiting the TORT Solutions to the NEA Suite of Benchmarks for 3D Transport Methods and Codes Over a Range in Parameter Space

    SciTech Connect

    Bekar, Kursat B; Azmy, Yousry

    2009-01-01

    Improved TORT solutions to the 3D transport codes' suite of benchmarks exercise are presented in this study. Preliminary TORT solutions to this benchmark indicate that the majority of benchmark quantities for most benchmark cases are computed with good accuracy, and that accuracy improves with model refinement. However, TORT fails to compute accurate results for some benchmark cases with aspect ratios drastically different from 1, possibly due to ray effects. In this work, we employ the standard approach of splitting the solution to the transport equation into an uncollided flux and a fully collided flux via the code sequence GRTUNCL3D and TORT to mitigate ray effects. The results of this code sequence presented in this paper show that the accuracy of most benchmark cases improved substantially. Furthermore, the iterative convergence problems reported for the preliminary TORT solutions have been resolved by bringing the computational cells' aspect ratio closer to unity and, more importantly, by using 64-bit arithmetic precision in the calculation sequence. Results of this study are also reported.

  18. On the numerical simulation of the ablative Rayleigh-Taylor instability in laser-driven ICF targets using the FastRad3D code

    NASA Astrophysics Data System (ADS)

    Bates, Jason; Schmitt, Andrew; Zalesak, Steve

    2015-11-01

    The ablative Rayleigh-Taylor (RT) instability is a key factor in the performance of directly-drive inertial-confinement-fusion (ICF) targets. Although this subject has been studied for quite some time, the accurate simulation of the ablative RT instability has proven to be a challenging task for many radiation hydrodynamics codes, particularly when it comes to capturing the ablatively-stabilized region of the linear dispersion spectrum and modeling ab initio perturbations. In this poster, we present results from recent two-dimensional numerical simulations of the ablative RT instability that were performed using the Eulerian code FastRad3D at the U.S. Naval Research Laboratory. We consider both planar and spherical geometries, low and moderate-Z target materials, different laser wavelengths and where possible, compare our findings with experiment data, linearized theory and/or results from other radiation hydrodynamics codes. Overall, we find that FastRad3D is capable of simulating the ablative RT instability quite accurately, although some uncertainties/discrepancies persist. We discuss these issues, as well as some of the numerical challenges associated with modeling this class of problems. Work supported by U.S. DOE/NNSA.

  19. Initial Self-Consistent 3D Electron-Cloud Simulations of the LHC Beam with the Code WARP+POSINST

    SciTech Connect

    Vay, J; Furman, M A; Cohen, R H; Friedman, A; Grote, D P

    2005-10-11

    We present initial results for the self-consistent beam-cloud dynamics simulations for a sample LHC beam, using a newly developed set of modeling capability based on a merge [1] of the three-dimensional parallel Particle-In-Cell (PIC) accelerator code WARP [2] and the electron-cloud code POSINST [3]. Although the storage ring model we use as a test bed to contain the beam is much simpler and shorter than the LHC, its lattice elements are realistically modeled, as is the beam and the electron cloud dynamics. The simulated mechanisms for generation and absorption of the electrons at the walls are based on previously validated models available in POSINST [3, 4].

  20. TRAC code assessment using data from SCTF Core-III, a large-scale 2D/3D facility

    SciTech Connect

    Boyack, B.E.; Shire, P.R.; Harmony, S.C.; Rhee, G.

    1988-01-01

    Nine tests from the SCTF Core-III configuration have been analyzed using TRAC-PF1/MOD1. The objectives of these assessment activities were to obtain a better understanding of the phenomena occurring during the refill and reflood phases of a large-break loss-of-coolant accident, to determine the accuracy to which key parameters are calculated, and to identify deficiencies in key code correlations and models that provide closure for the differential equations defining thermal-hydraulic phenomena in pressurized water reactors. Overall, the agreement between calculated and measured values of peak cladding temperature is reasonable. In addition, TRAC adequately predicts many of the trends observed in both the integral effect and separate effect tests conducted in SCTF Core-III. The importance of assessment activities that consider potential contributors to discrepancies between the measured and calculated results arising from three sources are described as those related to (1) knowledge about the facility configuration and operation, (2) facility modeling for code input, and (3) deficiencies in code correlations and models. An example is provided. 8 refs., 7 figs., 2 tabs.

  1. P1 adaptation of TRIPOLI-4® code for the use of 3D realistic core multigroup cross section generation

    NASA Astrophysics Data System (ADS)

    Cai, Li; Pénéliau, Yannick; Diop, Cheikh M.; Malvagi, Fausto

    2014-06-01

    In this paper, we discuss some improvements we recently implemented in the Monte-Carlo code TRIPOLI-4® associated with the homogenization and collapsing of subassemblies cross sections. The improvement offered us another approach to get critical multigroup cross sections with Monte-Carlo method. The new calculation method in TRIPOLI-4® tries to ensure the neutronic balances, the multiplicative factors and the critical flux spectra for some realistic geometries. We make it by at first improving the treatment of the energy transfer probability, the neutron excess weight and the neutron fission spectrum. This step is necessary for infinite geometries. The second step which will be enlarged in this paper is aimed at better dealing with the multigroup anisotropy distribution law for finite geometries. Usually, Monte-Carlo homogenized multi-group cross sections are validated within a core calculation by a deterministic code. Here, the validation of multigroup constants will also be carried out by Monte-Carlo core calculation code. Different subassemblies are tested with the new collapsing method, especially for the fast neutron reactors subassemblies.

  2. Lifting scheme-based method for joint coding 3D stereo digital cinema with luminace correction and optimized prediction

    NASA Astrophysics Data System (ADS)

    Darazi, R.; Gouze, A.; Macq, B.

    2009-01-01

    Reproducing a natural and real scene as we see in the real world everyday is becoming more and more popular. Stereoscopic and multi-view techniques are used for this end. However due to the fact that more information are displayed requires supporting technologies such as digital compression to ensure the storage and transmission of the sequences. In this paper, a new scheme for stereo image coding is proposed. The original left and right images are jointly coded. The main idea is to optimally exploit the existing correlation between the two images. This is done by the design of an efficient transform that reduces the existing redundancy in the stereo image pair. This approach was inspired by Lifting Scheme (LS). The novelty in our work is that the prediction step is been replaced by an hybrid step that consists in disparity compensation followed by luminance correction and an optimized prediction step. The proposed scheme can be used for lossless and for lossy coding. Experimental results show improvement in terms of performance and complexity compared to recently proposed methods.

  3. Speech coding, reconstruction and recognition using acoustics and electromagnetic waves

    DOEpatents

    Holzrichter, John F.; Ng, Lawrence C.

    1998-01-01

    The use of EM radiation in conjunction with simultaneously recorded acoustic speech information enables a complete mathematical coding of acoustic speech. The methods include the forming of a feature vector for each pitch period of voiced speech and the forming of feature vectors for each time frame of unvoiced, as well as for combined voiced and unvoiced speech. The methods include how to deconvolve the speech excitation function from the acoustic speech output to describe the transfer function each time frame. The formation of feature vectors defining all acoustic speech units over well defined time frames can be used for purposes of speech coding, speech compression, speaker identification, language-of-speech identification, speech recognition, speech synthesis, speech translation, speech telephony, and speech teaching.

  4. Speech coding, reconstruction and recognition using acoustics and electromagnetic waves

    DOEpatents

    Holzrichter, J.F.; Ng, L.C.

    1998-03-17

    The use of EM radiation in conjunction with simultaneously recorded acoustic speech information enables a complete mathematical coding of acoustic speech. The methods include the forming of a feature vector for each pitch period of voiced speech and the forming of feature vectors for each time frame of unvoiced, as well as for combined voiced and unvoiced speech. The methods include how to deconvolve the speech excitation function from the acoustic speech output to describe the transfer function each time frame. The formation of feature vectors defining all acoustic speech units over well defined time frames can be used for purposes of speech coding, speech compression, speaker identification, language-of-speech identification, speech recognition, speech synthesis, speech translation, speech telephony, and speech teaching. 35 figs.

  5. Assessment of a 3-D boundary layer code to predict heat transfer and flow losses in a turbine

    NASA Technical Reports Server (NTRS)

    Vatsa, V. N.

    1983-01-01

    The prediction of the complete flow field in a turbine passage is an extremely difficult task due to the complex three dimensional pattern which contains separation and attachment lines, a saddle point and horseshoe vortex. Whereas, in principle such a problem can be solved using full Navier-Stokes equations, in reality methods based on a Navier-Stokes solution procedure encounter difficulty in accurately predicting surface quantities (e.g., heat transfer) due to grid limitations imposed by the speed and size of the existing computers. On the other hand the overall problem is strongly three dimensional and too complex to be analyzed by the current design methods based on inviscid and/or viscous strip theories. Thus there is a strong need for enhancing the current prediction techniques through inclusion of 3-D viscous effects. A potentially simple and cost effective way to achieve this is to use a prediction method based on three dimensional boundary layer (3-DBL) theory. The major objective of this program is to assess the applicability of such a 3-DBL approach for the prediction of heat loads, boundary layer growth, pressure losses and streamline skewing in critical areas of a turbine passage. A brief discussion of the physical problem addressed here along with the overall approach is presented.

  6. A fully-neoclassical finite-orbit-width version of the CQL3D Fokker-Planck code

    NASA Astrophysics Data System (ADS)

    Petrov, Yu V.; Harvey, R. W.

    2016-11-01

    The time-dependent bounce-averaged CQL3D flux-conservative finite-difference Fokker-Planck equation (FPE) solver has been upgraded to include finite-orbit-width (FOW) capabilities which are necessary for an accurate description of neoclassical transport, losses to the walls, and transfer of particles, momentum, and heat to the scrape-off layer. The FOW modifications are implemented in the formulation of the neutral beam source, collision operator, RF quasilinear diffusion operator, and in synthetic particle diagnostics. The collisional neoclassical radial transport appears naturally in the FOW version due to the orbit-averaging of local collision coefficients coupled with transformation coefficients from local (R, Z) coordinates along each guiding-center orbit to the corresponding midplane computational coordinates, where the FPE is solved. In a similar way, the local quasilinear RF diffusion terms give rise to additional radial transport of orbits. We note that the neoclassical results are obtained for ‘full’ orbits, not dependent on a common small orbit-width approximation. Results of validation tests for the FOW version are also presented.

  7. Microdosimetry of alpha particles for simple and 3D voxelised geometries using MCNPX and Geant4 Monte Carlo codes.

    PubMed

    Elbast, M; Saudo, A; Franck, D; Petitot, F; Desbrée, A

    2012-07-01

    Microdosimetry using Monte Carlo simulation is a suitable technique to describe the stochastic nature of energy deposition by alpha particle at cellular level. Because of its short range, the energy imparted by this particle to the targets is highly non-uniform. Thus, to achieve accurate dosimetric results, the modelling of the geometry should be as realistic as possible. The objectives of the present study were to validate the use of the MCNPX and Geant4 Monte Carlo codes for microdosimetric studies using simple and three-dimensional voxelised geometry and to study their limit of validity in this last case. To that aim, the specific energy (z) deposited in the cell nucleus, the single-hit density of specific energy f(1)(z) and the mean-specific energy were calculated. Results show a good agreement when compared with the literature using simple geometry. The maximum percentage difference found is <6 %. For voxelised phantom, the study of the voxel size highlighted that the shape of the curve f(1)(z) obtained with MCNPX for <1 µm voxel size presents a significant difference with the shape of non-voxelised geometry. When using Geant4, little differences are observed whatever the voxel size is. Below 1 µm, the use of Geant4 is required. However, the calculation time is 10 times higher with Geant4 than MCNPX code in the same conditions.

  8. Half-Cell RF Gun Simulations with the Electromagnetic Particle-in-Cell Code VORPAL

    SciTech Connect

    Paul, K.; Dimitrov, D. A.; Busby, R.; Bruhwiler, D. L.; Smithe, D.; Cary, J. R.; Kewisch, J.; Kayran, D.; Calaga, R.; Ben-Zvi, I.

    2009-01-22

    We have simulated Brookhaven National Laboratory's half-cell superconducting RF gun design for a proposed high-current ERL using the three-dimensional, electromagnetic particle-in-cell code VORPAL. VORPAL computes the fully self-consistent electromagnetic fields produced by the electron bunches, meaning that it accurately models space-charge effects as well as bunch-to-bunch beam loading effects and the effects of higher-order cavity modes, though these are beyond the scope of this paper. We compare results from VORPAL to the well-established space-charge code PARMELA, using RF fields produced by SUPERFISH, as a benchmarking exercise in which the two codes should agree well.

  9. Development and Test of 2.5-Dimensional Electromagnetic PIC Simulation Code

    NASA Astrophysics Data System (ADS)

    Lee, Sang-Yun; Lee, Ensang; Kim, Khan-Hyuk; Seon, Jongho; Lee, Dong-Hun; Ryu, Kwang-Sun

    2015-03-01

    We have developed a 2.5-dimensional electromagnetic particle simulation code using the particle-in-cell (PIC) method to investigate electromagnetic phenomena that occur in space plasmas. Our code is based on the leap-frog method and the centered difference method for integration and differentiation of the governing equations. We adopted the relativistic Buneman-Boris method to solve the Lorentz force equation and the Esirkepov method to calculate the current density while maintaining charge conservation. Using the developed code, we performed test simulations for electron two-stream instability and electron temperature anisotropy induced instability with the same initial parameters as used in previously reported studies. The test simulation results are almost identical with those of the previous papers.

  10. Comparison of the 3D VERB Code Simulations of the Dynamic Evolution of the Outer and Inner Radiation Belts With the Reanalysis Obtained from Observations on Multiple Spacecraft

    NASA Astrophysics Data System (ADS)

    Shprits, Y.; Subbotin, D.; Ni, B.; Daae, M.; Kondrashov, D. A.; Hartinger, M.; Kim, K.; Orlova, K.; Nagai, T.; Friedel, R. H.; Chen, Y.

    2010-12-01

    In this study we present simulations of the inner and outer radiation belts using the Versatile Electron Radiation Belt (VERB) accounting for radial, pitch-angle, energy, and mixed diffusion. Qusi-linear diffusion coefficients are computed using the Full Diffusion Code (FDC) due to day-side and night-side chorus waves, magneto-sonic waves, phasmaspheric hiss waves, EMIC and hiss waves in the regions of plumes, lightning generated whistlers and anthropogenic whistlers. Sensitivity simulations show that the knowledge of wave spectral properties and spacial distribution of waves is crucially important for reproducing long term observations. The 3D VERB code simulations are compared to 3D reanalysis of the radiation belt fluxes obtained by blending the predictive model with observations from LANL GEO, CRRES, Akebono, and GPS. We also discuss the initial results of coupled RCM-VERB simulations. Finally, we present a statistical analysis of radiation belt phase space density obtained from reanalysis to explore sudden drop outs of the radiation belt fluxes and location of peaks in phase space density. The application of the developed tools to future measurements on board RBSP is discussed.

  11. Geometric phase coded metasurface: from polarization dependent directive electromagnetic wave scattering to diffusion-like scattering

    PubMed Central

    Chen, Ke; Feng, Yijun; Yang, Zhongjie; Cui, Li; Zhao, Junming; Zhu, Bo; Jiang, Tian

    2016-01-01

    Ultrathin metasurface compromising various sub-wavelength meta-particles offers promising advantages in controlling electromagnetic wave by spatially manipulating the wavefront characteristics across the interface. The recently proposed digital coding metasurface could even simplify the design and optimization procedures due to the digitalization of the meta-particle geometry. However, current attempts to implement the digital metasurface still utilize several structural meta-particles to obtain certain electromagnetic responses, and requiring time-consuming optimization especially in multi-bits coding designs. In this regard, we present herein utilizing geometric phase based single structured meta-particle with various orientations to achieve either 1-bit or multi-bits digital metasurface. Particular electromagnetic wave scattering patterns dependent on the incident polarizations can be tailored by the encoded metasurfaces with regular sequences. On the contrast, polarization insensitive diffusion-like scattering can also been successfully achieved by digital metasurface encoded with randomly distributed coding sequences leading to substantial suppression of backward scattering in a broadband microwave frequency. The proposed digital metasurfaces provide simple designs and reveal new opportunities for controlling electromagnetic wave scattering with or without polarization dependence. PMID:27775064

  12. Geometric phase coded metasurface: from polarization dependent directive electromagnetic wave scattering to diffusion-like scattering

    NASA Astrophysics Data System (ADS)

    Chen, Ke; Feng, Yijun; Yang, Zhongjie; Cui, Li; Zhao, Junming; Zhu, Bo; Jiang, Tian

    2016-10-01

    Ultrathin metasurface compromising various sub-wavelength meta-particles offers promising advantages in controlling electromagnetic wave by spatially manipulating the wavefront characteristics across the interface. The recently proposed digital coding metasurface could even simplify the design and optimization procedures due to the digitalization of the meta-particle geometry. However, current attempts to implement the digital metasurface still utilize several structural meta-particles to obtain certain electromagnetic responses, and requiring time-consuming optimization especially in multi-bits coding designs. In this regard, we present herein utilizing geometric phase based single structured meta-particle with various orientations to achieve either 1-bit or multi-bits digital metasurface. Particular electromagnetic wave scattering patterns dependent on the incident polarizations can be tailored by the encoded metasurfaces with regular sequences. On the contrast, polarization insensitive diffusion-like scattering can also been successfully achieved by digital metasurface encoded with randomly distributed coding sequences leading to substantial suppression of backward scattering in a broadband microwave frequency. The proposed digital metasurfaces provide simple designs and reveal new opportunities for controlling electromagnetic wave scattering with or without polarization dependence.

  13. Scattering of electromagnetic waves from 3D multilayer random rough surfaces based on the second-order small perturbation method: energy conservation, reflectivity, and emissivity.

    PubMed

    Sanamzadeh, Mohammadreza; Tsang, Leung; Johnson, Joel T; Burkholder, Robert J; Tan, Shurun

    2017-03-01

    A theoretical investigation of energy conservation, reflectivity, and emissivity in the scattering of electromagnetic waves from 3D multilayer media with random rough interfaces using the second-order small perturbation method (SPM2) is presented. The approach is based on the extinction theorem and develops integral equations for surface fields in the spectral domain. Using the SPM2, we calculate the scattered and transmitted coherent fields and incoherent fields. Reflected and transmitted powers are then found in the form of 2D integrations over wavenumber in the spectral domain. In the integrand, there is a summation over the spectral densities of each of the rough interfaces with each weighted by a corresponding kernel function. We show in this paper that there exists a "strong" condition of energy conservation in that the kernel functions multiplying the spectral density of each interface obey energy conservation exactly. This means that energy is conserved independent of the roughness spectral densities of the rough surfaces. Results of this strong condition are illustrated numerically for up to 50 rough interfaces without requiring specification of surface roughness properties. Two examples are illustrated. One is a multilayer configuration having weak contrasts between adjacent layers, random layer thicknesses, and randomly generated permittivity profiles. The second example is a photonic crystal of periodically alternating permittivities of larger dielectric contrast. The methodology is applied to study the effect of roughness on the brightness temperatures of the Antarctic ice sheet, which is characterized by layers of ice with permittivity fluctuations in addition to random rough interfaces. The results show that the influence of roughness can significantly increase horizontally polarized thermal emission while leaving vertically polarized emissions relatively unaffected.

  14. Boundary conditions for arbitrarily shaped and tightly focused laser pulses in electromagnetic codes

    NASA Astrophysics Data System (ADS)

    Thiele, Illia; Skupin, Stefan; Nuter, Rachel

    2016-09-01

    Investigation of laser matter interaction with electromagnetic codes requires to implement sources for the electromagnetic fields. A way to do so is to prescribe the fields at the numerical box boundaries in order to achieve the desired fields inside the numerical box. Here we show that the often used paraxial approximation can lead to unexpected field profiles with strong impact on the laser matter interaction results. We propose an efficient numerical algorithm to compute the required laser boundary conditions consistent with the Maxwell's equations for arbitrarily shaped, tightly focused laser pulses.

  15. NASA low-speed centrifugal compressor for 3-D viscous code assessment and fundamental flow physics research

    NASA Technical Reports Server (NTRS)

    Hathaway, M. D.; Wood, J. R.; Wasserbauer, C. A.

    1991-01-01

    A low speed centrifugal compressor facility recently built by the NASA Lewis Research Center is described. The purpose of this facility is to obtain detailed flow field measurements for computational fluid dynamic code assessment and flow physics modeling in support of Army and NASA efforts to advance small gas turbine engine technology. The facility is heavily instrumented with pressure and temperature probes, both in the stationary and rotating frames of reference, and has provisions for flow visualization and laser velocimetry. The facility will accommodate rotational speeds to 2400 rpm and is rated at pressures to 1.25 atm. The initial compressor stage being tested is geometrically and dynamically representative of modern high-performance centrifugal compressor stages with the exception of Mach number levels. Preliminary experimental investigations of inlet and exit flow uniformly and measurement repeatability are presented. These results demonstrate the high quality of the data which may be expected from this facility. The significance of synergism between computational fluid dynamic analysis and experimentation throughout the development of the low speed centrifugal compressor facility is demonstrated.

  16. Development of 3D beam-beam simulation for the Tevatron

    SciTech Connect

    Stern, E.; Amundson, J.; Spentzouris, P.; Valishev, A.; Qiang, J.; Ryne, R.; /LBL, Berkeley

    2007-06-01

    We present status of development of a 3D Beam-Beam simulation code for simulating the Fermilab Tevatron collider. The essential features of the code are 3D particle-in-cell Poisson solver for calculating the Beam-Beam electromagnetic interactions with additional modules for linear optics, machine impedance and chromaticity, and multiple bunch tracking. The simulations match synchrobetatron oscillations measured at the VEPP-2M collider. The impedance calculations show beam instability development consistent with analytic expressions.

  17. Electromagnetic simulations of the ASDEX Upgrade ICRF Antenna with the TOPICA code

    SciTech Connect

    Krivska, A.; Milanesio, D.; Bobkov, V.; Braun, F.; Noterdaeme, J.-M.

    2009-11-26

    Accurate and efficient simulation tools are necessary to optimize the ICRF antenna design for a set of operational conditions. The TOPICA code was developed for performance prediction and for the analysis of ICRF antenna systems in the presence of plasma, given realistic antenna geometries. Fully 3D antenna geometries can be adopted in TOPICA, just as in available commercial codes. But while those commercial codes cannot operate with a plasma loading, the TOPICA code correctly accounts for realistic plasma loading conditions, by means of the coupling with 1D FELICE code. This paper presents the evaluation of the electric current distribution on the structure, of the parallel electric field in the region between the straps and the plasma and the computation of sheaths driving RF potentials. Results of TOPICA simulations will help to optimize and re-design the ICRF ASDEX Upgrade antenna in order to reduce tungsten (W) sputtering attributed to the rectified sheath effect during ICRF operation.

  18. Comparison of a 3-D multi-group SN particle transport code with Monte Carlo for intracavitary brachytherapy of the cervix uteri.

    PubMed

    Gifford, Kent A; Wareing, Todd A; Failla, Gregory; Horton, John L; Eifel, Patricia J; Mourtada, Firas

    2009-12-03

    A patient dose distribution was calculated by a 3D multi-group S N particle transport code for intracavitary brachytherapy of the cervix uteri and compared to previously published Monte Carlo results. A Cs-137 LDR intracavitary brachytherapy CT data set was chosen from our clinical database. MCNPX version 2.5.c, was used to calculate the dose distribution. A 3D multi-group S N particle transport code, Attila version 6.1.1 was used to simulate the same patient. Each patient applicator was built in SolidWorks, a mechanical design package, and then assembled with a coordinate transformation and rotation for the patient. The SolidWorks exported applicator geometry was imported into Attila for calculation. Dose matrices were overlaid on the patient CT data set. Dose volume histograms and point doses were compared. The MCNPX calculation required 14.8 hours, whereas the Attila calculation required 22.2 minutes on a 1.8 GHz AMD Opteron CPU. Agreement between Attila and MCNPX dose calculations at the ICRU 38 points was within +/- 3%. Calculated doses to the 2 cc and 5 cc volumes of highest dose differed by not more than +/- 1.1% between the two codes. Dose and DVH overlays agreed well qualitatively. Attila can calculate dose accurately and efficiently for this Cs-137 CT-based patient geometry. Our data showed that a three-group cross-section set is adequate for Cs-137 computations. Future work is aimed at implementing an optimized version of Attila for radiotherapy calculations.

  19. LLNL-Earth3D

    SciTech Connect

    2013-10-01

    Earth3D is a computer code designed to allow fast calculation of seismic rays and travel times through a 3D model of the Earth. LLNL is using this for earthquake location and global tomography efforts and such codes are of great interest to the Earth Science community.

  20. SPECT Imaging of 2-D and 3-D Distributed Sources with Near-Field Coded Aperture Collimation: Computer Simulation and Real Data Validation.

    PubMed

    Mu, Zhiping; Dobrucki, Lawrence W; Liu, Yi-Hwa

    The imaging of distributed sources with near-field coded aperture (CA) remains extremely challenging and is broadly considered unsuitable for single-photon emission computerized tomography (SPECT). This study proposes a novel CA SPECT reconstruction approach and evaluates the feasibilities of imaging and reconstructing distributed hot sources and cold lesions using near-field CA collimation and iterative image reconstruction. Computer simulations were designed to compare CA and pinhole collimations in two-dimensional radionuclide imaging. Digital phantoms were created and CA images of the phantoms were reconstructed using maximum likelihood expectation maximization (MLEM). Errors and the contrast-to-noise ratio (CNR) were calculated and image resolution was evaluated. An ex vivo rat heart with myocardial infarction was imaged using a micro-SPECT system equipped with a custom-made CA module and a commercial 5-pinhole collimator. Rat CA images were reconstructed via the three-dimensional (3-D) MLEM algorithm developed for CA SPECT with and without correction for a large projection angle, and 5-pinhole images were reconstructed using the commercial software provided by the SPECT system. Phantom images of CA were markedly improved in terms of image quality, quantitative root-mean-squared error, and CNR, as compared to pinhole images. CA and pinhole images yielded similar image resolution, while CA collimation resulted in fewer noise artifacts. CA and pinhole images of the rat heart were well reconstructed and the myocardial perfusion defects could be clearly discerned from 3-D CA and 5-pinhole SPECT images, whereas 5-pinhole SPECT images suffered from severe noise artifacts. Image contrast of CA SPECT was further improved after correction for the large projection angle used in the rat heart imaging. The computer simulations and small-animal imaging study presented herein indicate that the proposed 3-D CA SPECT imaging and reconstruction approaches worked reasonably

  1. Validation of 3D Code KATRIN For Fast Neutron Fluence Calculation of VVER-1000 Reactor Pressure Vessel by Ex-Vessel Measurements and Surveillance Specimens Results

    NASA Astrophysics Data System (ADS)

    Dzhalandinov, A.; Tsofin, V.; Kochkin, V.; Panferov, P.; Timofeev, A.; Reshetnikov, A.; Makhotin, D.; Erak, D.; Voloschenko, A.

    2016-02-01

    Usually the synthesis of two-dimensional and one-dimensional discrete ordinate calculations is used to evaluate neutron fluence on VVER-1000 reactor pressure vessel (RPV) for prognosis of radiation embrittlement. But there are some cases when this approach is not applicable. For example the latest projects of VVER-1000 have upgraded surveillance program. Containers with surveillance specimens are located on the inner surface of RPV with fast neutron flux maximum. Therefore, the synthesis approach is not suitable enough for calculation of local disturbance of neutron field in RPV inner surface behind the surveillance specimens because of their complicated and heterogeneous structure. In some cases the VVER-1000 core loading consists of fuel assemblies with different fuel height and the applicability of synthesis approach is also ambiguous for these fuel cycles. Also, the synthesis approach is not enough correct for the neutron fluence estimation at the RPV area above core top. Because of these reasons only the 3D neutron transport codes seem to be satisfactory for calculation of neutron fluence on the VVER-1000 RPV. The direct 3D calculations are also recommended by modern regulations.

  2. Validation of the RPLUS3D Code for Supersonic Inlet Applications Involving Three-Dimensional Shock Wave-Boundary Layer Interactions

    NASA Technical Reports Server (NTRS)

    Kapoor, Kamlesh; Anderson, Bernhard H.; Shaw, Robert J.

    1994-01-01

    A three-dimensional computational fluid dynamics code, RPLUS3D, which was developed for the reactive propulsive flows of ramjets and scramjets, was validated for glancing shock wave-boundary layer interactions. Both laminar and turbulent flows were studied. A supersonic flow over a wedge mounted on a flat plate was numerically simulated. For the laminar case, the static pressure distribution, velocity vectors, and particle traces on the flat plate were obtained. For turbulent flow, both the Baldwin-Lomax and Chien two-equation turbulent models were used. The static pressure distributions, pitot pressure, and yaw angle profiles were computed. In addition, the velocity vectors and particle traces on the flat plate were also obtained from the computed solution. Overall, the computed results for both laminar and turbulent cases compared very well with the experimentally obtained data.

  3. Frozen Rotor and Sliding Mesh Models Applied to the 3D Simulation of the Francis-99 Tokke Turbine with Code_Saturne

    NASA Astrophysics Data System (ADS)

    Tonello, N.; Eude, Y.; de Laage de Meux, B.; Ferrand, M.

    2017-01-01

    The steady-state operation of the Francis-99, Tokke turbine [1-3] has been simulated numerically at different loads using the open source, CAD and CFD software, SALOME [4] Code_Saturne [5]. The full 3D mesh of the Tokke turbine provided for the Second Francis-99 Workshop has been adapted and modified to work with the solver. Results are compared for the frozen-rotor and the unsteady, conservative sliding mesh approach over three operating points, showing that good agreement with the experimental data is obtained with both models without having to tune the CFD models for each operating point. Approaches to the simulation of transient operation are also presented with results of work in progress.

  4. Impact of event-specific chorus wave realization for modeling the October 8-9, 2012, event using the LANL DREAM3D diffusion code

    NASA Astrophysics Data System (ADS)

    Cunningham, G.; Tu, W.; Chen, Y.; Reeves, G. D.; Henderson, M. G.; Baker, D. N.; Blake, J. B.; Spence, H.

    2013-12-01

    During the interval October 8-9, 2012, the phase-space density (PSD) of high-energy electrons exhibited a dropout preceding an intense enhancement observed by the MagEIS and REPT instruments aboard the Van Allen Probes. The evolution of the PSD suggests heating by chorus waves, which were observed to have high intensities at the time of the enhancement [1]. Although intense chorus waves were also observed during the first Dst dip on October 8, no PSD enhancement was observed at this time. We demonstrate a quantitative reproduction of the entire event that makes use of three recent modifications to the LANL DREAM3D diffusion code: 1) incorporation of a time-dependent, low-energy, boundary condition from the MagEIS instrument, 2) use of a time-dependent estimate of the chorus wave intensity derived from observations of POES low-energy electron precipitation, and 3) use of an estimate of the last closed drift shell, beyond which electrons are assumed to have a lifetime that is proportional to their drift period around earth. The key features of the event are quantitatively reproduced by the simulation, including the dropout on October 8, and a rapid increase in PSD early on October 9, with a peak near L*=4.2. The DREAM3D code predicts the dropout on October 8 because this feature is dominated by magnetospheric compression and outward radial diffusion-the L* of the last closed drift-shell reaches a minimum value of 5.33 at 1026 UT on October 8. We find that a ';statistical' wave model based on historical CRRES measurements binned in AE* does not reproduce the enhancement because the peak wave amplitudes are only a few 10's of pT, whereas an ';event-specific' model reproduces both the magnitude and timing of the enhancement very well, a s shown in the Figure, because the peak wave amplitudes are 10x higher. [1] 'Electron Acceleration in the Heart of the Van Allen Radiation Belts', G. D. Reeves et al., Science 1237743, Published online 25 July 2013 [DOI:10.1126/science

  5. Use of the FLUKA Monte Carlo code for 3D patient-specific dosimetry on PET-CT and SPECT-CT images.

    PubMed

    Botta, F; Mairani, A; Hobbs, R F; Vergara Gil, A; Pacilio, M; Parodi, K; Cremonesi, M; Coca Pérez, M A; Di Dia, A; Ferrari, M; Guerriero, F; Battistoni, G; Pedroli, G; Paganelli, G; Torres Aroche, L A; Sgouros, G

    2013-11-21

    Patient-specific absorbed dose calculation for nuclear medicine therapy is a topic of increasing interest. 3D dosimetry at the voxel level is one of the major improvements for the development of more accurate calculation techniques, as compared to the standard dosimetry at the organ level. This study aims to use the FLUKA Monte Carlo code to perform patient-specific 3D dosimetry through direct Monte Carlo simulation on PET-CT and SPECT-CT images. To this aim, dedicated routines were developed in the FLUKA environment. Two sets of simulations were performed on model and phantom images. Firstly, the correct handling of PET and SPECT images was tested under the assumption of homogeneous water medium by comparing FLUKA results with those obtained with the voxel kernel convolution method and with other Monte Carlo-based tools developed to the same purpose (the EGS-based 3D-RD software and the MCNP5-based MCID). Afterwards, the correct integration of the PET/SPECT and CT information was tested, performing direct simulations on PET/CT images for both homogeneous (water) and non-homogeneous (water with air, lung and bone inserts) phantoms. Comparison was performed with the other Monte Carlo tools performing direct simulation as well. The absorbed dose maps were compared at the voxel level. In the case of homogeneous water, by simulating 10(8) primary particles a 2% average difference with respect to the kernel convolution method was achieved; such difference was lower than the statistical uncertainty affecting the FLUKA results. The agreement with the other tools was within 3–4%, partially ascribable to the differences among the simulation algorithms. Including the CT-based density map, the average difference was always within 4% irrespective of the medium (water, air, bone), except for a maximum 6% value when comparing FLUKA and 3D-RD in air. The results confirmed that the routines were properly developed, opening the way for the use of FLUKA for patient-specific, image

  6. Use of the FLUKA Monte Carlo code for 3D patient-specific dosimetry on PET-CT and SPECT-CT images*

    PubMed Central

    Botta, F; Mairani, A; Hobbs, R F; Vergara Gil, A; Pacilio, M; Parodi, K; Cremonesi, M; Coca Pérez, M A; Di Dia, A; Ferrari, M; Guerriero, F; Battistoni, G; Pedroli, G; Paganelli, G; Torres Aroche, L A; Sgouros, G

    2014-01-01

    Patient-specific absorbed dose calculation for nuclear medicine therapy is a topic of increasing interest. 3D dosimetry at the voxel level is one of the major improvements for the development of more accurate calculation techniques, as compared to the standard dosimetry at the organ level. This study aims to use the FLUKA Monte Carlo code to perform patient-specific 3D dosimetry through direct Monte Carlo simulation on PET-CT and SPECT-CT images. To this aim, dedicated routines were developed in the FLUKA environment. Two sets of simulations were performed on model and phantom images. Firstly, the correct handling of PET and SPECT images was tested under the assumption of homogeneous water medium by comparing FLUKA results with those obtained with the voxel kernel convolution method and with other Monte Carlo-based tools developed to the same purpose (the EGS-based 3D-RD software and the MCNP5-based MCID). Afterwards, the correct integration of the PET/SPECT and CT information was tested, performing direct simulations on PET/CT images for both homogeneous (water) and non-homogeneous (water with air, lung and bone inserts) phantoms. Comparison was performed with the other Monte Carlo tools performing direct simulation as well. The absorbed dose maps were compared at the voxel level. In the case of homogeneous water, by simulating 108 primary particles a 2% average difference with respect to the kernel convolution method was achieved; such difference was lower than the statistical uncertainty affecting the FLUKA results. The agreement with the other tools was within 3–4%, partially ascribable to the differences among the simulation algorithms. Including the CT-based density map, the average difference was always within 4% irrespective of the medium (water, air, bone), except for a maximum 6% value when comparing FLUKA and 3D-RD in air. The results confirmed that the routines were properly developed, opening the way for the use of FLUKA for patient-specific, image

  7. Use of the FLUKA Monte Carlo code for 3D patient-specific dosimetry on PET-CT and SPECT-CT images

    NASA Astrophysics Data System (ADS)

    Botta, F.; Mairani, A.; Hobbs, R. F.; Vergara Gil, A.; Pacilio, M.; Parodi, K.; Cremonesi, M.; Coca Pérez, M. A.; Di Dia, A.; Ferrari, M.; Guerriero, F.; Battistoni, G.; Pedroli, G.; Paganelli, G.; Torres Aroche, L. A.; Sgouros, G.

    2013-11-01

    Patient-specific absorbed dose calculation for nuclear medicine therapy is a topic of increasing interest. 3D dosimetry at the voxel level is one of the major improvements for the development of more accurate calculation techniques, as compared to the standard dosimetry at the organ level. This study aims to use the FLUKA Monte Carlo code to perform patient-specific 3D dosimetry through direct Monte Carlo simulation on PET-CT and SPECT-CT images. To this aim, dedicated routines were developed in the FLUKA environment. Two sets of simulations were performed on model and phantom images. Firstly, the correct handling of PET and SPECT images was tested under the assumption of homogeneous water medium by comparing FLUKA results with those obtained with the voxel kernel convolution method and with other Monte Carlo-based tools developed to the same purpose (the EGS-based 3D-RD software and the MCNP5-based MCID). Afterwards, the correct integration of the PET/SPECT and CT information was tested, performing direct simulations on PET/CT images for both homogeneous (water) and non-homogeneous (water with air, lung and bone inserts) phantoms. Comparison was performed with the other Monte Carlo tools performing direct simulation as well. The absorbed dose maps were compared at the voxel level. In the case of homogeneous water, by simulating 108 primary particles a 2% average difference with respect to the kernel convolution method was achieved; such difference was lower than the statistical uncertainty affecting the FLUKA results. The agreement with the other tools was within 3-4%, partially ascribable to the differences among the simulation algorithms. Including the CT-based density map, the average difference was always within 4% irrespective of the medium (water, air, bone), except for a maximum 6% value when comparing FLUKA and 3D-RD in air. The results confirmed that the routines were properly developed, opening the way for the use of FLUKA for patient-specific, image

  8. Development of the 3D Parallel Particle-In-Cell Code IMPACT to Simulate the Ion Beam Transport System of VENUS (Abstract)

    SciTech Connect

    Qiang, J.; Leitner, D.; Todd, D.S.; Ryne, R.D.

    2005-03-15

    The superconducting ECR ion source VENUS serves as the prototype injector ion source for the Rare Isotope Accelerator (RIA) driver linac. The RIA driver linac requires a great variety of high charge state ion beams with up to an order of magnitude higher intensity than currently achievable with conventional ECR ion sources. In order to design the beam line optics of the low energy beam line for the RIA front end for the wide parameter range required for the RIA driver accelerator, reliable simulations of the ion beam extraction from the ECR ion source through the ion mass analyzing system are essential. The RIA low energy beam transport line must be able to transport intense beams (up to 10 mA) of light and heavy ions at 30 keV.For this purpose, LBNL is developing the parallel 3D particle-in-cell code IMPACT to simulate the ion beam transport from the ECR extraction aperture through the analyzing section of the low energy transport system. IMPACT, a parallel, particle-in-cell code, is currently used to model the superconducting RF linac section of RIA and is being modified in order to simulate DC beams from the ECR ion source extraction. By using the high performance of parallel supercomputing we will be able to account consistently for the changing space charge in the extraction region and the analyzing section. A progress report and early results in the modeling of the VENUS source will be presented.

  9. Development of the 3D Parallel Particle-In-Cell Code IMPACT to Simulate the Ion Beam Transport System of VENUS (Abstract)

    NASA Astrophysics Data System (ADS)

    Qiang, J.; Leitner, D.; Todd, D. S.; Ryne, R. D.

    2005-03-01

    The superconducting ECR ion source VENUS serves as the prototype injector ion source for the Rare Isotope Accelerator (RIA) driver linac. The RIA driver linac requires a great variety of high charge state ion beams with up to an order of magnitude higher intensity than currently achievable with conventional ECR ion sources. In order to design the beam line optics of the low energy beam line for the RIA front end for the wide parameter range required for the RIA driver accelerator, reliable simulations of the ion beam extraction from the ECR ion source through the ion mass analyzing system are essential. The RIA low energy beam transport line must be able to transport intense beams (up to 10 mA) of light and heavy ions at 30 keV. For this purpose, LBNL is developing the parallel 3D particle-in-cell code IMPACT to simulate the ion beam transport from the ECR extraction aperture through the analyzing section of the low energy transport system. IMPACT, a parallel, particle-in-cell code, is currently used to model the superconducting RF linac section of RIA and is being modified in order to simulate DC beams from the ECR ion source extraction. By using the high performance of parallel supercomputing we will be able to account consistently for the changing space charge in the extraction region and the analyzing section. A progress report and early results in the modeling of the VENUS source will be presented.

  10. Implementation of agronomical and geochemical modules into a 3D groundwater code for assessing nitrate storage and transport through unconfined Chalk aquifer

    NASA Astrophysics Data System (ADS)

    Picot-Colbeaux, Géraldine; Devau, Nicolas; Thiéry, Dominique; Pettenati, Marie; Surdyk, Nicolas; Parmentier, Marc; Amraoui, Nadia; Crastes de Paulet, François; André, Laurent

    2016-04-01

    Chalk aquifer is the main water resource for domestic water supply in many parts in northern France. In same basin, groundwater is frequently affected by quality problems concerning nitrates. Often close to or above the drinking water standards, nitrate concentration in groundwater is mainly due to historical agriculture practices, combined with leakage and aquifer recharge through the vadose zone. The complexity of processes occurring into such an environment leads to take into account a lot of knowledge on agronomy, geochemistry and hydrogeology in order to understand, model and predict the spatiotemporal evolution of nitrate content and provide a decision support tool for the water producers and stakeholders. To succeed in this challenge, conceptual and numerical models representing accurately the Chalk aquifer specificity need to be developed. A multidisciplinary approach is developed to simulate storage and transport from the ground surface until groundwater. This involves a new agronomic module "NITRATE" (NItrogen TRansfer for Arable soil to groundwaTEr), a soil-crop model allowing to calculate nitrogen mass balance in arable soil, and the "PHREEQC" numerical code for geochemical calculations, both coupled with the 3D transient groundwater numerical code "MARTHE". Otherwise, new development achieved on MARTHE code allows the use of dual porosity and permeability calculations needed in the fissured Chalk aquifer context. This method concerning the integration of existing multi-disciplinary tools is a real challenge to reduce the number of parameters by selecting the relevant equations and simplifying the equations without altering the signal. The robustness and the validity of these numerical developments are tested step by step with several simulations constrained by climate forcing, land use and nitrogen inputs over several decades. In the first time, simulations are performed in a 1D vertical unsaturated soil column for representing experimental nitrates

  11. A user's manual for the Electromagnetic Surface Patch code: ESP version 3

    NASA Technical Reports Server (NTRS)

    Newman, E. H.; Dilsavor, R. L.

    1987-01-01

    This report serves as a user's manual for Version III of the Electromagnetic Surface Patch Code or ESP code. ESP is user-oriented, based on the method of moments (MM) for treating geometries consisting of an interconnection of thin wires and perfectly conducting polygonal plates. Wire/plate junctions must be about 0.1 lambda or more from any plate edge. Several plates may intersect along a common edge. Excitation may be by either a delta-gap voltage generator or by a plane wave. The thin wires may have finite conductivity and also may contain lumped loads. The code computes most of the usual quantities of interest such as current distribution, input impedance, radiation efficiency, mutual coupling, far zone gain patterns (both polarizations) and radar-cross-section (both/cross polarizations).

  12. Present capabilities and new developments in antenna modeling with the numerical electromagnetics code NEC

    SciTech Connect

    Burke, G.J.

    1988-04-08

    Computer modeling of antennas, since its start in the late 1960's, has become a powerful and widely used tool for antenna design. Computer codes have been developed based on the Method-of-Moments, Geometrical Theory of Diffraction, or integration of Maxwell's equations. Of such tools, the Numerical Electromagnetics Code-Method of Moments (NEC) has become one of the most widely used codes for modeling resonant sized antennas. There are several reasons for this including the systematic updating and extension of its capabilities, extensive user-oriented documentation and accessibility of its developers for user assistance. The result is that there are estimated to be several hundred users of various versions of NEC world wide. 23 refs., 10 figs.

  13. Evaluation of the scale dependent dynamic SGS model in the open source code caffa3d.MBRi in wall-bounded flows

    NASA Astrophysics Data System (ADS)

    Draper, Martin; Usera, Gabriel

    2015-04-01

    The Scale Dependent Dynamic Model (SDDM) has been widely validated in large-eddy simulations using pseudo-spectral codes [1][2][3]. The scale dependency, particularly the potential law, has been proved also in a priori studies [4][5]. To the authors' knowledge there have been only few attempts to use the SDDM in finite difference (FD) and finite volume (FV) codes [6][7], finding some improvements with the dynamic procedures (scale independent or scale dependent approach), but not showing the behavior of the scale-dependence parameter when using the SDDM. The aim of the present paper is to evaluate the SDDM in the open source code caffa3d.MBRi, an updated version of the code presented in [8]. caffa3d.MBRi is a FV code, second-order accurate, parallelized with MPI, in which the domain is divided in unstructured blocks of structured grids. To accomplish this, 2 cases are considered: flow between flat plates and flow over a rough surface with the presence of a model wind turbine, taking for this case the experimental data presented in [9]. In both cases the standard Smagorinsky Model (SM), the Scale Independent Dynamic Model (SIDM) and the SDDM are tested. As presented in [6][7] slight improvements are obtained with the SDDM. Nevertheless, the behavior of the scale-dependence parameter supports the generalization of the dynamic procedure proposed in the SDDM, particularly taking into account that no explicit filter is used (the implicit filter is unknown). [1] F. Porté-Agel, C. Meneveau, M.B. Parlange. "A scale-dependent dynamic model for large-eddy simulation: application to a neutral atmospheric boundary layer". Journal of Fluid Mechanics, 2000, 415, 261-284. [2] E. Bou-Zeid, C. Meneveau, M. Parlante. "A scale-dependent Lagrangian dynamic model for large eddy simulation of complex turbulent flows". Physics of Fluids, 2005, 17, 025105 (18p). [3] R. Stoll, F. Porté-Agel. "Dynamic subgrid-scale models for momentum and scalar fluxes in large-eddy simulations of

  14. Full electromagnetic Vlasov code simulation of the Kelvin-Helmholtz instability

    SciTech Connect

    Umeda, Takayuki; Miwa, Jun-ichiro; Matsumoto, Yosuke; Togano, Kentaro; Nakamura, Takuma K. M.; Shinohara, Iku; Fukazawa, Keiichiro

    2010-05-15

    Recent advancement in numerical techniques for Vlasov simulations and their application to cross-scale coupling in the plasma universe are discussed. Magnetohydrodynamic (MHD) simulations are now widely used for numerical modeling of global and macroscopic phenomena. In the framework of the MHD approximation, however, diffusion coefficients such as resistivity and adiabatic index are given from empirical models. Thus there are recent attempts to understand first-principle kinetic processes in macroscopic phenomena, such as magnetic reconnection and the Kelvin-Helmholtz (KH) instability via full kinetic particle-in-cell and Vlasov codes. In the present study, a benchmark test for a new four-dimensional full electromagnetic Vlasov code is performed. First, the computational speed of the Vlasov code is measured and a linear performance scaling is obtained on a massively parallel supercomputer with more than 12 000 cores. Second, a first-principle Vlasov simulation of the KH instability is performed in order to evaluate current status of numerical techniques for Vlasov simulations. The KH instability is usually adopted as a benchmark test problem for guiding-center Vlasov codes, in which a cyclotron motion of charged particles is neglected. There is not any full electromagnetic Vlasov simulation of the KH instability; this is because it is difficult to follow E-vectorxB-vector drift motion accurately without approximations. The present first-principle Vlasov simulation has successfully represented the formation of KH vortices and its secondary instability. These results suggest that Vlasov code simulations would be a powerful approach for studies of cross-scale coupling on future Peta-scale supercomputers.

  15. Interactive Graphics Utility for Army NEC (Numerical Electromagnetics Code) Automation (IGUANA). Computer Program Package.

    DTIC Science & Technology

    1985-09-01

    STANDARDS-1963-A 4 . 1 1 1 1 ’ 1 ’I l 1 4r AD-A160 652 Contractor Report 307 September 1985 INTERACTIVE GRAPHICS UTILITY FOR ARMY NEC AUTOMATION ( IGUANA ...20363-5100 62543N NO8CM41 88509 I1I TITLE (owkide Securft Ci,,zifteaninV 191, INTERACTIVE GRAPHICS UTILITY FOR ARMY NFC AUTOMATION ( IGUANA , Computer...GROUP Sue-GROUP Numerical Electromagnetics Code (NEC) Subdecks .1’* The Interactive Graphics Utility for Army NEC Automation ( IGUANA ) is a system

  16. On the Numerical Dispersion of Electromagnetic Particle-In-Cell Code : Finite Grid Instability

    SciTech Connect

    Meyers, Michael David; Huang, Chengkun; Zeng, Yong; Yi, Sunghwan; Albright, Brian James

    2014-07-15

    The Particle-In-Cell (PIC) method is widely used in relativistic particle beam and laser plasma modeling. However, the PIC method exhibits numerical instabilities that can render unphysical simulation results or even destroy the simulation. For electromagnetic relativistic beam and plasma modeling, the most relevant numerical instabilities are the finite grid instability and the numerical Cherenkov instability. We review the numerical dispersion relation of the electromagnetic PIC algorithm to analyze the origin of these instabilities. We rigorously derive the faithful 3D numerical dispersion of the PIC algorithm, and then specialize to the Yee FDTD scheme. In particular, we account for the manner in which the PIC algorithm updates and samples the fields and distribution function. Temporal and spatial phase factors from solving Maxwell's equations on the Yee grid with the leapfrog scheme are also explicitly accounted for. Numerical solutions to the electrostatic-like modes in the 1D dispersion relation for a cold drifting plasma are obtained for parameters of interest. In the succeeding analysis, we investigate how the finite grid instability arises from the interaction of the numerical 1D modes admitted in the system and their aliases. The most significant interaction is due critically to the correct representation of the operators in the dispersion relation. We obtain a simple analytic expression for the peak growth rate due to this interaction.

  17. DOD-SBIR Structured Multi-Resolution PIC Code for Electromagnetic Plasma Simulations, Final Report

    SciTech Connect

    Vay, J L; Grote, D P; Friedman, A

    2010-04-22

    A novel electromagnetic solver with mesh refinement capability was implemented in Warp. The solver allows for calculations in 2-1/2 and 3 dimensions, includes the standard Yee stencil, and the Cole-Karkkainen stencil for lower numerical dispersion along the principal axes. Warp implementation of the Cole-Karkkainen stencil includes an extension to perfectly matched layers (PML) for absorption of waves, and is preserving the conservation property of charge conserving current deposition schemes, like the Buneman-Villanesor and Esirkepov methods. Warp's mesh refinement framework (originally developed for electrostatic calculations) was augmented to allow for electromagnetic capability, following the methodology presented in [1] extended to an arbitrary number of refinement levels. Other developments include a generalized particle injection method, internal conductors using stair-cased approximation, and subcycling of particle pushing. The solver runs in parallel using MPI message passing, with a choice at runtime of 1D, 2D and 3D domain decomposition, and is shown to scale linearly on a test problem up-to 32,768 CPUs. The novel solver was tested on the modeling of filamentation instability, fast ignition, ion beam induced plasma wake, and laser plasma acceleration.

  18. Development of an Implicit, Charge and Energy Conserving 2D Electromagnetic PIC Code on Advanced Architectures

    NASA Astrophysics Data System (ADS)

    Payne, Joshua; Taitano, William; Knoll, Dana; Liebs, Chris; Murthy, Karthik; Feltman, Nicolas; Wang, Yijie; McCarthy, Colleen; Cieren, Emanuel

    2012-10-01

    In order to solve problems such as the ion coalescence and slow MHD shocks fully kinetically we developed a fully implicit 2D energy and charge conserving electromagnetic PIC code, PlasmaApp2D. PlasmaApp2D differs from previous implicit PIC implementations in that it will utilize advanced architectures such as GPUs and shared memory CPU systems, with problems too large to fit into cache. PlasmaApp2D will be a hybrid CPU-GPU code developed primarily to run on the DARWIN cluster at LANL utilizing four 12-core AMD Opteron CPUs and two NVIDIA Tesla GPUs per node. MPI will be used for cross-node communication, OpenMP will be used for on-node parallelism, and CUDA will be used for the GPUs. Development progress and initial results will be presented.

  19. Numerical simulations of the ablative Rayleigh-Taylor instability in planar inertial-confinement-fusion targets using the FastRad3D code

    NASA Astrophysics Data System (ADS)

    Bates, J. W.; Schmitt, A. J.; Karasik, M.; Zalesak, S. T.

    2016-12-01

    The ablative Rayleigh-Taylor (RT) instability is a central issue in the performance of laser-accelerated inertial-confinement-fusion targets. Historically, the accurate numerical simulation of this instability has been a challenging task for many radiation hydrodynamics codes, particularly when it comes to capturing the ablatively stabilized region of the linear dispersion spectrum and modeling ab initio perturbations. Here, we present recent results from two-dimensional numerical simulations of the ablative RT instability in planar laser-ablated foils that were performed using the Eulerian code FastRad3D. Our study considers polystyrene, (cryogenic) deuterium-tritium, and beryllium target materials, quarter- and third-micron laser light, and low and high laser intensities. An initial single-mode surface perturbation is modeled in our simulations as a small modulation to the target mass density and the ablative RT growth-rate is calculated from the time history of areal-mass variations once the target reaches a steady-state acceleration. By performing a sequence of such simulations with different perturbation wavelengths, we generate a discrete dispersion spectrum for each of our examples and find that in all cases the linear RT growth-rate γ is well described by an expression of the form γ = α [ k g / ( 1 + ɛ k L m ) ] 1 / 2 - β k V a , where k is the perturbation wavenumber, g is the acceleration of the target, Lm is the minimum density scale-length, Va is the ablation velocity, and ɛ is either one or zero. The dimensionless coefficients α and β in the above formula depend on the particular target and laser parameters and are determined from two-dimensional simulation results through the use of a nonlinear curve-fitting procedure. While our findings are generally consistent with those of Betti et al. (Phys. Plasmas 5, 1446 (1998)), the ablative RT growth-rates predicted in this investigation are somewhat smaller than the values previously reported for the

  20. Development of Numerical Codes for Modeling Electromagnetic Behavior at High Frequencies Near Large Objects

    NASA Technical Reports Server (NTRS)

    Joshi, R. P.; Deshpande, M. D. (Technical Monitor)

    2003-01-01

    A study into the problem of determining electromagnetic solutions at high frequencies for problems involving complex geometries, large sizes and multiple sources (e.g. antennas) has been initiated. Typical applications include the behavior of antennas (and radiators) installed on complex conducting structures (e.g. ships, aircrafts, etc..) with strong interactions between antennas, the radiation patterns, and electromagnetic signals is of great interest for electromagnetic compatibility control. This includes the overall performance evaluation and control of all on-board radiating systems, electromagnetic interference, and personnel radiation hazards. Electromagnetic computational capability exists at NASA LaRC, and many of the codes developed are based on the Moment Method (MM). However, the MM is computationally intensive, and this places a limit on the size of objects and structures that can be modeled. Here, two approaches are proposed: (i) a current-based hybrid scheme that combines the MM with Physical optics, and (ii) an Alternating Direction Implicit-Finite Difference Time Domain (ADI-FDTD) method. The essence of a hybrid technique is to split the overall scattering surface(s) into two regions: (a) a MM zone (MMZ) which can be used over any part of the given geometry, but is most essential over irregular and "non-smooth" geometries, and (b) a PO sub-region (POSR). Currents induced on the scattering and reflecting surfaces can then be computed in two ways depending on whether the region belonged to the MMZ or was part of the POSR. For the MMZ, the current calculations proceed in terms of basis functions with undetermined coefficients (as in the usual MM method), and the answer obtained by solving a system of linear equations. Over the POSR, conduction is obtained as a superposition of two contributions: (i) currents due to the incident magnetic field, and (ii) currents produced by the mutual induction from conduction within the MMZ. This effectively leads to

  1. [3D emulation of epicardium dynamic mapping].

    PubMed

    Lu, Jun; Yang, Cui-Wei; Fang, Zu-Xiang

    2005-03-01

    In order to realize epicardium dynamic mapping of the whole atria, 3-D graphics are drawn with OpenGL. Some source codes are introduced in the paper to explain how to produce, read, and manipulate 3-D model data.

  2. Spherical 3D isotropic wavelets

    NASA Astrophysics Data System (ADS)

    Lanusse, F.; Rassat, A.; Starck, J.-L.

    2012-04-01

    Context. Future cosmological surveys will provide 3D large scale structure maps with large sky coverage, for which a 3D spherical Fourier-Bessel (SFB) analysis in spherical coordinates is natural. Wavelets are particularly well-suited to the analysis and denoising of cosmological data, but a spherical 3D isotropic wavelet transform does not currently exist to analyse spherical 3D data. Aims: The aim of this paper is to present a new formalism for a spherical 3D isotropic wavelet, i.e. one based on the SFB decomposition of a 3D field and accompany the formalism with a public code to perform wavelet transforms. Methods: We describe a new 3D isotropic spherical wavelet decomposition based on the undecimated wavelet transform (UWT) described in Starck et al. (2006). We also present a new fast discrete spherical Fourier-Bessel transform (DSFBT) based on both a discrete Bessel transform and the HEALPIX angular pixelisation scheme. We test the 3D wavelet transform and as a toy-application, apply a denoising algorithm in wavelet space to the Virgo large box cosmological simulations and find we can successfully remove noise without much loss to the large scale structure. Results: We have described a new spherical 3D isotropic wavelet transform, ideally suited to analyse and denoise future 3D spherical cosmological surveys, which uses a novel DSFBT. We illustrate its potential use for denoising using a toy model. All the algorithms presented in this paper are available for download as a public code called MRS3D at http://jstarck.free.fr/mrs3d.html

  3. On the numerical dispersion of electromagnetic particle-in-cell code: Finite grid instability

    SciTech Connect

    Meyers, M.D.; Huang, C.-K.; Zeng, Y.; Yi, S.A.; Albright, B.J.

    2015-09-15

    The Particle-In-Cell (PIC) method is widely used in relativistic particle beam and laser plasma modeling. However, the PIC method exhibits numerical instabilities that can render unphysical simulation results or even destroy the simulation. For electromagnetic relativistic beam and plasma modeling, the most relevant numerical instabilities are the finite grid instability and the numerical Cherenkov instability. We review the numerical dispersion relation of the Electromagnetic PIC model. We rigorously derive the faithful 3-D numerical dispersion relation of the PIC model, for a simple, direct current deposition scheme, which does not conserve electric charge exactly. We then specialize to the Yee FDTD scheme. In particular, we clarify the presence of alias modes in an eigenmode analysis of the PIC model, which combines both discrete and continuous variables. The manner in which the PIC model updates and samples the fields and distribution function, together with the temporal and spatial phase factors from solving Maxwell's equations on the Yee grid with the leapfrog scheme, is explicitly accounted for. Numerical solutions to the electrostatic-like modes in the 1-D dispersion relation for a cold drifting plasma are obtained for parameters of interest. In the succeeding analysis, we investigate how the finite grid instability arises from the interaction of the numerical modes admitted in the system and their aliases. The most significant interaction is due critically to the correct representation of the operators in the dispersion relation. We obtain a simple analytic expression for the peak growth rate due to this interaction, which is then verified by simulation. We demonstrate that our analysis is readily extendable to charge conserving models.

  4. On the numerical dispersion of electromagnetic particle-in-cell code: Finite grid instability

    NASA Astrophysics Data System (ADS)

    Meyers, M. D.; Huang, C.-K.; Zeng, Y.; Yi, S. A.; Albright, B. J.

    2015-09-01

    The Particle-In-Cell (PIC) method is widely used in relativistic particle beam and laser plasma modeling. However, the PIC method exhibits numerical instabilities that can render unphysical simulation results or even destroy the simulation. For electromagnetic relativistic beam and plasma modeling, the most relevant numerical instabilities are the finite grid instability and the numerical Cherenkov instability. We review the numerical dispersion relation of the Electromagnetic PIC model. We rigorously derive the faithful 3-D numerical dispersion relation of the PIC model, for a simple, direct current deposition scheme, which does not conserve electric charge exactly. We then specialize to the Yee FDTD scheme. In particular, we clarify the presence of alias modes in an eigenmode analysis of the PIC model, which combines both discrete and continuous variables. The manner in which the PIC model updates and samples the fields and distribution function, together with the temporal and spatial phase factors from solving Maxwell's equations on the Yee grid with the leapfrog scheme, is explicitly accounted for. Numerical solutions to the electrostatic-like modes in the 1-D dispersion relation for a cold drifting plasma are obtained for parameters of interest. In the succeeding analysis, we investigate how the finite grid instability arises from the interaction of the numerical modes admitted in the system and their aliases. The most significant interaction is due critically to the correct representation of the operators in the dispersion relation. We obtain a simple analytic expression for the peak growth rate due to this interaction, which is then verified by simulation. We demonstrate that our analysis is readily extendable to charge conserving models.

  5. Evaluation of 3D radio-frequency electromagnetic fields for any matching and coupling conditions by the use of basis functions.

    PubMed

    Tiberi, Gianluigi; Fontana, Nunzia; Monorchio, Agostino; Stara, Riccardo; Retico, Alessandra; Tosetti, Michela

    2015-12-01

    A procedure for evaluating radio-frequency electromagnetic fields in anatomical human models for any matching and coupling conditions is introduced. The procedure resorts to the extraction of basis functions: such basis functions, which represent the fields produced by each individual port without any residual coupling, are derived through an algebraic procedure which uses the S parameter matrix and the fields calculated in one (only) full-wave simulation. The basis functions are then used as building-blocks for calculating the fields for any other S parameter matrix. The proposed approach can be used both for volume coil driven in quadrature and for parallel transmission configuration.

  6. Evaluation of 3D radio-frequency electromagnetic fields for any matching and coupling conditions by the use of basis functions

    NASA Astrophysics Data System (ADS)

    Tiberi, Gianluigi; Fontana, Nunzia; Monorchio, Agostino; Stara, Riccardo; Retico, Alessandra; Tosetti, Michela

    2015-12-01

    A procedure for evaluating radio-frequency electromagnetic fields in anatomical human models for any matching and coupling conditions is introduced. The procedure resorts to the extraction of basis functions: such basis functions, which represent the fields produced by each individual port without any residual coupling, are derived through an algebraic procedure which uses the S parameter matrix and the fields calculated in one (only) full-wave simulation. The basis functions are then used as building-blocks for calculating the fields for any other S parameter matrix. The proposed approach can be used both for volume coil driven in quadrature and for parallel transmission configuration.

  7. 3D numerical simulation for the transient electromagnetic field excited by the central loop based on the vector finite-element method

    NASA Astrophysics Data System (ADS)

    Li, J. H.; Zhu, Z. Q.; Liu, S. C.; Zeng, S. H.

    2011-12-01

    Based on the principle of abnormal field algorithms, Helmholtz equations for electromagnetic field have been deduced. We made the electric field Helmholtz equation the governing equation, and derived the corresponding system of vector finite element method equations using the Galerkin method. For solving the governing equation using the vector finite element method, we divided the computing domain into homogenous brick elements, and used Whitney-type vector basis functions. After obtaining the electric field's anomaly field in the Laplace domain using the vector finite element method, we used the Gaver-Stehfest algorithm to transform the electric field's anomaly field to the time domain, and obtained the impulse response of magnetic field's anomaly field through the Faraday law of electromagnetic induction. By comparing 1D analytic solutions of quasi-H-type geoelectric models, the accuracy of the vector finite element method is tested. For the low resistivity brick geoelectric model, the plot shape of electromotive force computed using the vector finite element method coincides with that of the integral equation method and finite difference in time domain solutions.

  8. MARE2DEM: a 2-D inversion code for controlled-source electromagnetic and magnetotelluric data

    NASA Astrophysics Data System (ADS)

    Key, Kerry

    2016-10-01

    This work presents MARE2DEM, a freely available code for 2-D anisotropic inversion of magnetotelluric (MT) data and frequency-domain controlled-source electromagnetic (CSEM) data from onshore and offshore surveys. MARE2DEM parametrizes the inverse model using a grid of arbitrarily shaped polygons, where unstructured triangular or quadrilateral grids are typically used due to their ease of construction. Unstructured grids provide significantly more geometric flexibility and parameter efficiency than the structured rectangular grids commonly used by most other inversion codes. Transmitter and receiver components located on topographic slopes can be tilted parallel to the boundary so that the simulated electromagnetic fields accurately reproduce the real survey geometry. The forward solution is implemented with a goal-oriented adaptive finite-element method that automatically generates and refines unstructured triangular element grids that conform to the inversion parameter grid, ensuring accurate responses as the model conductivity changes. This dual-grid approach is significantly more efficient than the conventional use of a single grid for both the forward and inverse meshes since the more detailed finite-element meshes required for accurate responses do not increase the memory requirements of the inverse problem. Forward solutions are computed in parallel with a highly efficient scaling by partitioning the data into smaller independent modeling tasks consisting of subsets of the input frequencies, transmitters and receivers. Non-linear inversion is carried out with a new Occam inversion approach that requires fewer forward calls. Dense matrix operations are optimized for memory and parallel scalability using the ScaLAPACK parallel library. Free parameters can be bounded using a new non-linear transformation that leaves the transformed parameters nearly the same as the original parameters within the bounds, thereby reducing non-linear smoothing effects. Data

  9. A study on H and O-H grid generation and associated flow codes for gas turbine 3D Navier Stokes analyses

    NASA Astrophysics Data System (ADS)

    Choi, D.; Knight, C. J.

    1991-06-01

    A method to generate H and O-H grid systems for 3D gas turbine geometries has been developed. It is a simple procedure which solves a set of elliptic equations starting from an initial grid system generated algebraically. This grid generation procedure is for 3D Navier-Stokes analysis based on the scalar or diagonalized form of approximate factorization. The grids generated by this procedure have been applied to 3D heat transfer calculations and compared with experimental results. Detailed comparisons are given for both H and O-H grid topologies, considering the Low Aspect Ratio Turbine (LART) and using a two-equation turbulence model with viscous sublayer resolution.

  10. 3D polarisation speckle as a demonstration of tensor version of the van Cittert-Zernike theorem for stochastic electromagnetic beams

    NASA Astrophysics Data System (ADS)

    Ma, Ning; Zhao, Juan; Hanson, Steen G.; Takeda, Mitsuo; Wang, Wei

    2016-10-01

    Laser speckle has received extensive studies of its basic properties and associated applications. In the majority of research on speckle phenomena, the random optical field has been treated as a scalar optical field, and the main interest has been concentrated on their statistical properties and applications of its intensity distribution. Recently, statistical properties of random electric vector fields referred to as Polarization Speckle have come to attract new interest because of their importance in a variety of areas with practical applications such as biomedical optics and optical metrology. Statistical phenomena of random electric vector fields have close relevance to the theories of speckles, polarization and coherence theory. In this paper, we investigate the correlation tensor for stochastic electromagnetic fields modulated by a depolarizer consisting of a rough-surfaced retardation plate. Under the assumption that the microstructure of the scattering surface on the depolarizer is as fine as to be unresolvable in our observation region, we have derived a relationship between the polarization matrix/coherency matrix for the modulated electric fields behind the rough-surfaced retardation plate and the coherence matrix under the free space geometry. This relation is regarded as entirely analogous to the van Cittert-Zernike theorem of classical coherence theory. Within the paraxial approximation as represented by the ABCD-matrix formalism, the three-dimensional structure of the generated polarization speckle is investigated based on the correlation tensor, indicating a typical carrot structure with a much longer axial dimension than the extent in its transverse dimension.

  11. Transport of 3D space charge dominated beams

    NASA Astrophysics Data System (ADS)

    Lü, Jian-Qin

    2013-10-01

    In this paper we present the theoretical analysis and the computer code design for the intense pulsed beam transport. Intense beam dynamics is a very important issue in low-energy high-current accelerators and beam transport systems. This problem affects beam transmission and beam qualities. Therefore, it attracts the attention of the accelerator physicists worldwide. The analysis and calculation for the intense beam dynamics are very complicated, because the state of particle motion is dominated not only by the applied electromagnetic fields, but also by the beam-induced electromagnetic fields (self-fields). Moreover, the self fields are related to the beam dimensions and particle distributions. So, it is very difficult to get the self-consistent solutions of particle motion analytically. For this reason, we combine the Lie algebraic method and the particle in cell (PIC) scheme together to simulate intense 3D beam transport. With the Lie algebraic method we analyze the particle nonlinear trajectories in the applied electromagnetic fields up to third order approximation, and with the PIC algorithm we calculate the space charge effects to the particle motion. Based on the theoretical analysis, we have developed a computer code, which calculates beam transport systems consisting of electrostatic lenses, electrostatic accelerating columns, solenoid lenses, magnetic and electric quadruples, magnetic sextupoles, octopuses and different kinds of electromagnetic analyzers. The optimization calculations and the graphic display for the calculated results are provided by the code.

  12. Computational electronics and electromagnetics

    SciTech Connect

    Shang, C. C.

    1997-02-01

    The Computational Electronics and Electromagnetics thrust area at Lawrence Livermore National Laboratory serves as the focal point for engineering R&D activities for developing computer-based design, analysis, and tools for theory. Key representative applications include design of particle accelerator cells and beamline components; engineering analysis and design of high-power components, photonics, and optoelectronics circuit design; EMI susceptibility analysis; and antenna synthesis. The FY-96 technology-base effort focused code development on (1) accelerator design codes; (2) 3-D massively parallel, object-oriented time-domain EM codes; (3) material models; (4) coupling and application of engineering tools for analysis and design of high-power components; (5) 3-D spectral-domain CEM tools; and (6) enhancement of laser drilling codes. Joint efforts with the Power Conversion Technologies thrust area include development of antenna systems for compact, high-performance radar, in addition to novel, compact Marx generators. 18 refs., 25 figs., 1 tab.

  13. 3D Computations and Experiments

    SciTech Connect

    Couch, R; Faux, D; Goto, D; Nikkel, D

    2004-04-05

    This project consists of two activities. Task A, Simulations and Measurements, combines all the material model development and associated numerical work with the materials-oriented experimental activities. The goal of this effort is to provide an improved understanding of dynamic material properties and to provide accurate numerical representations of those properties for use in analysis codes. Task B, ALE3D Development, involves general development activities in the ALE3D code with the focus of improving simulation capabilities for problems of mutual interest to DoD and DOE. Emphasis is on problems involving multi-phase flow, blast loading of structures and system safety/vulnerability studies.

  14. 3D field harmonics

    SciTech Connect

    Caspi, S.; Helm, M.; Laslett, L.J.

    1991-03-30

    We have developed an harmonic representation for the three dimensional field components within the windings of accelerator magnets. The form by which the field is presented is suitable for interfacing with other codes that make use of the 3D field components (particle tracking and stability). The field components can be calculated with high precision and reduced cup time at any location (r,{theta},z) inside the magnet bore. The same conductor geometry which is used to simulate line currents is also used in CAD with modifications more readily available. It is our hope that the format used here for magnetic fields can be used not only as a means of delivering fields but also as a way by which beam dynamics can suggest correction to the conductor geometry. 5 refs., 70 figs.

  15. Real-time catheter tracking for high-dose-rate prostate brachytherapy using an electromagnetic 3D-guidance device: A preliminary performance study

    SciTech Connect

    Zhou Jun; Sebastian, Evelyn; Mangona, Victor; Yan Di

    2013-02-15

    Purpose: In order to increase the accuracy and speed of catheter reconstruction in a high-dose-rate (HDR) prostate implant procedure, an automatic tracking system has been developed using an electromagnetic (EM) device (trakSTAR, Ascension Technology, VT). The performance of the system, including the accuracy and noise level with various tracking parameters and conditions, were investigated. Methods: A direct current (dc) EM transmitter (midrange model) and a sensor with diameter of 1.3 mm (Model 130) were used in the trakSTAR system for tracking catheter position during HDR prostate brachytherapy. Localization accuracy was assessed under both static and dynamic analyses conditions. For the static analysis, a calibration phantom was used to investigate error dependency on operating room (OR) table height (bottom vs midposition vs top), sensor position (distal tip of catheter vs connector end of catheter), direction [left-right (LR) vs anterior-posterior (AP) vs superior-inferior (SI)], sampling frequency (40 vs 80 vs 120 Hz), and interference from OR equipment (present vs absent). The mean and standard deviation of the localization offset in each direction and the corresponding error vectors were calculated. For dynamic analysis, the paths of five straight catheters were tracked to study the effects of directions, sampling frequency, and interference of EM field. Statistical analysis was conducted to compare the results in different configurations. Results: When interference was present in the static analysis, the error vectors were significantly higher at the top table position (3.3 {+-} 1.3 vs 1.8 {+-} 0.9 mm at bottom and 1.7 {+-} 1.0 mm at middle, p < 0.001), at catheter end position (3.1 {+-} 1.1 vs 1.4 {+-} 0.7 mm at the tip position, p < 0.001), and at 40 Hz sampling frequency (2.6 {+-} 1.1 vs 2.4 {+-} 1.5 mm at 80 Hz and 1.8 {+-} 1.1 at 160 Hz, p < 0.001). So did the mean offset errors in the LR direction (-1.7 {+-} 1.4 vs 0.4 {+-} 0.5 mm in AP and 0

  16. Evaluation of a thin-slot formalism for finite-difference time-domain electromagnetics codes

    SciTech Connect

    Turner, C.D.; Bacon, L.D.

    1987-03-01

    A thin-slot formalism for use with finite-difference time-domain (FDTD) electromagnetics codes has been evaluated in both two and three dimensions. This formalism allows narrow slots to be modeled in the wall of a scatterer without reducing the space grid size to the gap width. In two dimensions, the evaluation involves the calculation of the total fields near two infinitesimally thin coplanar strips separated by a gap. A method-of-moments (MoM) solution of the same problem is used as a benchmark for comparison. Results in two dimensions show that up to 10% error can be expected in total electric and magnetic fields both near (lambda/40) and far (1 lambda) from the slot. In three dimensions, the evaluation is similar. The finite-length slot is placed in a finite plate and an MoM surface patch solution is used for the benchmark. These results, although less extensive than those in two dimensions, show that slightly larger errors can be expected. Considering the approximations made near the slot in incorporating the formalism, the results are very promising. Possibilities also exist for applying this formalism to walls of arbitrary thickness and to other types of slots, such as overlapping joints. 11 refs., 25 figs., 6 tabs.

  17. Computational Electronics and Electromagnetics

    SciTech Connect

    DeFord, J.F.

    1993-03-01

    The Computational Electronics and Electromagnetics thrust area is a focal point for computer modeling activities in electronics and electromagnetics in the Electronics Engineering Department of Lawrence Livermore National Laboratory (LLNL). Traditionally, they have focused their efforts in technical areas of importance to existing and developing LLNL programs, and this continues to form the basis for much of their research. A relatively new and increasingly important emphasis for the thrust area is the formation of partnerships with industry and the application of their simulation technology and expertise to the solution of problems faced by industry. The activities of the thrust area fall into three broad categories: (1) the development of theoretical and computational models of electronic and electromagnetic phenomena, (2) the development of useful and robust software tools based on these models, and (3) the application of these tools to programmatic and industrial problems. In FY-92, they worked on projects in all of the areas outlined above. The object of their work on numerical electromagnetic algorithms continues to be the improvement of time-domain algorithms for electromagnetic simulation on unstructured conforming grids. The thrust area is also investigating various technologies for conforming-grid mesh generation to simplify the application of their advanced field solvers to design problems involving complicated geometries. They are developing a major code suite based on the three-dimensional (3-D), conforming-grid, time-domain code DSI3D. They continue to maintain and distribute the 3-D, finite-difference time-domain (FDTD) code TSAR, which is installed at several dozen university, government, and industry sites.

  18. An Assessment of Some Design Constraints on Heat Production of a 3D Conceptual EGS Model Using an Open-Source Geothermal Reservoir Simulation Code

    SciTech Connect

    Yidong Xia; Mitch Plummer; Robert Podgorney; Ahmad Ghassemi

    2016-02-01

    Performance of heat production process over a 30-year period is assessed in a conceptual EGS model with a geothermal gradient of 65K per km depth in the reservoir. Water is circulated through a pair of parallel wells connected by a set of single large wing fractures. The results indicate that the desirable output electric power rate and lifespan could be obtained under suitable material properties and system parameters. A sensitivity analysis on some design constraints and operation parameters indicates that 1) the fracture horizontal spacing has profound effect on the long-term performance of heat production, 2) the downward deviation angle for the parallel doublet wells may help overcome the difficulty of vertical drilling to reach a favorable production temperature, and 3) the thermal energy production rate and lifespan has close dependence on water mass flow rate. The results also indicate that the heat production can be improved when the horizontal fracture spacing, well deviation angle, and production flow rate are under reasonable conditions. To conduct the reservoir modeling and simulations, an open-source, finite element based, fully implicit, fully coupled hydrothermal code, namely FALCON, has been developed and used in this work. Compared with most other existing codes that are either closed-source or commercially available in this area, this new open-source code has demonstrated a code development strategy that aims to provide an unparalleled easiness for user-customization and multi-physics coupling. Test results have shown that the FALCON code is able to complete the long-term tests efficiently and accurately, thanks to the state-of-the-art nonlinear and linear solver algorithms implemented in the code.

  19. Europeana and 3D

    NASA Astrophysics Data System (ADS)

    Pletinckx, D.

    2011-09-01

    The current 3D hype creates a lot of interest in 3D. People go to 3D movies, but are we ready to use 3D in our homes, in our offices, in our communication? Are we ready to deliver real 3D to a general public and use interactive 3D in a meaningful way to enjoy, learn, communicate? The CARARE project is realising this for the moment in the domain of monuments and archaeology, so that real 3D of archaeological sites and European monuments will be available to the general public by 2012. There are several aspects to this endeavour. First of all is the technical aspect of flawlessly delivering 3D content over all platforms and operating systems, without installing software. We have currently a working solution in PDF, but HTML5 will probably be the future. Secondly, there is still little knowledge on how to create 3D learning objects, 3D tourist information or 3D scholarly communication. We are still in a prototype phase when it comes to integrate 3D objects in physical or virtual museums. Nevertheless, Europeana has a tremendous potential as a multi-facetted virtual museum. Finally, 3D has a large potential to act as a hub of information, linking to related 2D imagery, texts, video, sound. We describe how to create such rich, explorable 3D objects that can be used intuitively by the generic Europeana user and what metadata is needed to support the semantic linking.

  20. Comparison of the 3-D Deterministic Neutron Transport Code Attila® To Measure Data, MCNP And MCNPX For The Advanced Test Reactor

    SciTech Connect

    D. Scott Lucas; D. S. Lucas

    2005-09-01

    An LDRD (Laboratory Directed Research and Development) project is underway at the Idaho National Laboratory (INL) to apply the three-dimensional multi-group deterministic neutron transport code (Attila®) to criticality, flux and depletion calculations of the Advanced Test Reactor (ATR). This paper discusses the development of Attila models for ATR, capabilities of Attila, the generation and use of different cross-section libraries, and comparisons to ATR data, MCNP, MCNPX and future applications.

  1. Adapting hierarchical bidirectional inter prediction on a GPU-based platform for 2D and 3D H.264 video coding

    NASA Astrophysics Data System (ADS)

    Rodríguez-Sánchez, Rafael; Martínez, José Luis; Cock, Jan De; Fernández-Escribano, Gerardo; Pieters, Bart; Sánchez, José L.; Claver, José M.; de Walle, Rik Van

    2013-12-01

    The H.264/AVC video coding standard introduces some improved tools in order to increase compression efficiency. Moreover, the multi-view extension of H.264/AVC, called H.264/MVC, adopts many of them. Among the new features, variable block-size motion estimation is one which contributes to high coding efficiency. Furthermore, it defines a different prediction structure that includes hierarchical bidirectional pictures, outperforming traditional Group of Pictures patterns in both scenarios: single-view and multi-view. However, these video coding techniques have high computational complexity. Several techniques have been proposed in the literature over the last few years which are aimed at accelerating the inter prediction process, but there are no works focusing on bidirectional prediction or hierarchical prediction. In this article, with the emergence of many-core processors or accelerators, a step forward is taken towards an implementation of an H.264/AVC and H.264/MVC inter prediction algorithm on a graphics processing unit. The results show a negligible rate distortion drop with a time reduction of up to 98% for the complete H.264/AVC encoder.

  2. 3d-3d correspondence revisited

    DOE PAGES

    Chung, Hee -Joong; Dimofte, Tudor; Gukov, Sergei; ...

    2016-04-21

    In fivebrane compactifications on 3-manifolds, we point out the importance of all flat connections in the proper definition of the effective 3d N = 2 theory. The Lagrangians of some theories with the desired properties can be constructed with the help of homological knot invariants that categorify colored Jones polynomials. Higgsing the full 3d theories constructed this way recovers theories found previously by Dimofte-Gaiotto-Gukov. As a result, we also consider the cutting and gluing of 3-manifolds along smooth boundaries and the role played by all flat connections in this operation.

  3. 3-D Modeling of Magnetic Fields for the Lithium Tokamak eXperiment

    NASA Astrophysics Data System (ADS)

    Logan, N.; Berzak, L.; Kaita, R.; Majeski, R.; Menard, J.; Zakharov, L.

    2010-11-01

    The Lithium Tokamak eXperiment (LTX) is designed to investigate low-recycling operating regimes by surrounding 85% of the last closed flux surface with liquid lithium evaporated onto a copper and stainless steel shell conformal to the plasma. Fields generated by currents in this conducting shell have significant effects on magnetic configurations. To understand these effects, the commercially available code Aether [http://www.fieldp.com] is used to simulate time varying magnetic fields in a 3-D model of LTX. The model is built using LTX CAD files and divided into a regular mesh for computing the evolution of coupled electromagnetic vector quantities through time and space. Applicable boundary conditions and symmetries are analyzed. Comparisons with measured data, results from a 2-D code, and results from a 3-D code designed specifically for LTX demonstrate the possible benefits and limitations of using this commercial code.

  4. Validation of two 3-D numerical computation codes for the flows in an annular cascade of high turning angle turbine blades

    NASA Astrophysics Data System (ADS)

    Wensheng, Wang; Fengxian, Zhang; Yanji, Xu; Naixing, Chen

    This paper describes and validates two improved three-dimensional numerical methods employed for calculating the flows in an annular cascade of high turning angle turbine blades tested by the authors in the annular cascade wind tunnel of the Institute of Engineering Thermophysics. Comparisons between the predictions and measurements were made on the static pressure contours of blade pressure and suction surfaces, and the spanwise distributions of pitchwise area-averaged static pressure coefficient and flow angle in the downstream of the cascade. The agreement between the calculated results and experimental data shows good and validates the reliability and applicability of the computation codes.

  5. SHAPEMOL: a 3D code for calculating CO line emission in planetary and protoplanetary nebulae. Detailed model-fitting of the complex nebula NGC 6302

    NASA Astrophysics Data System (ADS)

    Santander-García, M.; Bujarrabal, V.; Koning, N.; Steffen, W.

    2015-01-01

    Context. Modern instrumentation in radioastronomy constitutes a valuable tool for studying the Universe: ALMA has reached unprecedented sensitivities and spatial resolution, while Herschel/HIFI has opened a new window (most of the sub-mm and far-infrared ranges are only accessible from space) for probing molecular warm gas (~50-1000 K). On the other hand, the software SHAPE has emerged in the past few years as a standard tool for determining the morphology and velocity field of different kinds of gaseous emission nebulae via spatio-kinematical modelling. Standard SHAPE implements radiative transfer solving, but it is only available for atomic species and not for molecules. Aims: Being aware of the growing importance of the development of tools for simplifying the analyses of molecular data from new-era observatories, we introduce the computer code shapemol, a complement to SHAPE, with which we intend to fill the so-far under-developed molecular niche. Methods: shapemol enables user-friendly, spatio-kinematic modelling with accurate non-LTE calculations of excitation and radiative transfer in CO lines. Currently, it allows radiative transfer solving in the 12CO and 13CO J = 1-0 to J = 17-16 lines, but its implementation permits easily extending the code to different transitions and other molecular species, either by the code developers or by the user. Used along SHAPE, shapemol allows easily generating synthetic maps to test against interferometric observations, as well as synthetic line profiles to match single-dish observations. Results: We give a full description of how shapemol works, and we discuss its limitations and the sources of uncertainty to be expected in the final synthetic profiles or maps. As an example of the power and versatility of shapemol, we build a model of the molecular envelope of the planetary nebula NGC 6302 and compare it with 12CO and 13CO J = 2-1 interferometric maps from SMA and high-J transitions from Herschel/HIFI. We find the

  6. RT3D tutorials for GMS users

    SciTech Connect

    Clement, T.P.; Jones, N.L.

    1998-02-01

    RT3D (Reactive Transport in 3-Dimensions) is a computer code that solves coupled partial differential equations that describe reactive-flow and transport of multiple mobile and/or immobile species in a three dimensional saturated porous media. RT3D was developed from the single-species transport code, MT3D (DoD-1.5, 1997 version). As with MT3D, RT3D also uses the USGS groundwater flow model MODFLOW for computing spatial and temporal variations in groundwater head distribution. This report presents a set of tutorial problems that are designed to illustrate how RT3D simulations can be performed within the Department of Defense Groundwater Modeling System (GMS). GMS serves as a pre- and post-processing interface for RT3D. GMS can be used to define all the input files needed by RT3D code, and later the code can be launched from within GMS and run as a separate application. Once the RT3D simulation is completed, the solution can be imported to GMS for graphical post-processing. RT3D v1.0 supports several reaction packages that can be used for simulating different types of reactive contaminants. Each of the tutorials, described below, provides training on a different RT3D reaction package. Each reaction package has different input requirements, and the tutorials are designed to describe these differences. Furthermore, the tutorials illustrate the various options available in GMS for graphical post-processing of RT3D results. Users are strongly encouraged to complete the tutorials before attempting to use RT3D and GMS on a routine basis.

  7. HST3D; a computer code for simulation of heat and solute transport in three-dimensional ground-water flow systems

    USGS Publications Warehouse

    Kipp, K.L.

    1987-01-01

    The Heat- and Soil-Transport Program (HST3D) simulates groundwater flow and associated heat and solute transport in three dimensions. The three governing equations are coupled through the interstitial pore velocity, the dependence of the fluid density on pressure, temperature, the solute-mass fraction , and the dependence of the fluid viscosity on temperature and solute-mass fraction. The solute transport equation is for only a single, solute species with possible linear equilibrium sorption and linear decay. Finite difference techniques are used to discretize the governing equations using a point-distributed grid. The flow-, heat- and solute-transport equations are solved , in turn, after a particle Gauss-reduction scheme is used to modify them. The modified equations are more tightly coupled and have better stability for the numerical solutions. The basic source-sink term represents wells. A complex well flow model may be used to simulate specified flow rate and pressure conditions at the land surface or within the aquifer, with or without pressure and flow rate constraints. Boundary condition types offered include specified value, specified flux, leakage, heat conduction, and approximate free surface, and two types of aquifer influence functions. All boundary conditions can be functions of time. Two techniques are available for solution of the finite difference matrix equations. One technique is a direct-elimination solver, using equations reordered by alternating diagonal planes. The other technique is an iterative solver, using two-line successive over-relaxation. A restart option is available for storing intermediate results and restarting the simulation at an intermediate time with modified boundary conditions. This feature also can be used as protection against computer system failure. Data input and output may be in metric (SI) units or inch-pound units. Output may include tables of dependent variables and parameters, zoned-contour maps, and plots of the

  8. Real-Time Motion Capture Toolbox (RTMocap): an open-source code for recording 3-D motion kinematics to study action-effect anticipations during motor and social interactions.

    PubMed

    Lewkowicz, Daniel; Delevoye-Turrell, Yvonne

    2016-03-01

    We present here a toolbox for the real-time motion capture of biological movements that runs in the cross-platform MATLAB environment (The MathWorks, Inc., Natick, MA). It provides instantaneous processing of the 3-D movement coordinates of up to 20 markers at a single instant. Available functions include (1) the setting of reference positions, areas, and trajectories of interest; (2) recording of the 3-D coordinates for each marker over the trial duration; and (3) the detection of events to use as triggers for external reinforcers (e.g., lights, sounds, or odors). Through fast online communication between the hardware controller and RTMocap, automatic trial selection is possible by means of either a preset or an adaptive criterion. Rapid preprocessing of signals is also provided, which includes artifact rejection, filtering, spline interpolation, and averaging. A key example is detailed, and three typical variations are developed (1) to provide a clear understanding of the importance of real-time control for 3-D motion in cognitive sciences and (2) to present users with simple lines of code that can be used as starting points for customizing experiments using the simple MATLAB syntax. RTMocap is freely available (http://sites.google.com/site/RTMocap/) under the GNU public license for noncommercial use and open-source development, together with sample data and extensive documentation.

  9. A fast mode decision algorithm for multiview auto-stereoscopic 3D video coding based on mode and disparity statistic analysis

    NASA Astrophysics Data System (ADS)

    Ding, Cong; Sang, Xinzhu; Zhao, Tianqi; Yan, Binbin; Leng, Junmin; Yuan, Jinhui; Zhang, Ying

    2012-11-01

    Multiview video coding (MVC) is essential for applications of the auto-stereoscopic three-dimensional displays. However, the computational complexity of MVC encoders is tremendously huge. Fast algorithms are very desirable for the practical applications of MVC. Based on joint early termination , the selection of inter-view prediction and the optimization of the process of Inter8×8 modes by comparison, a fast macroblock(MB) mode selection algorithm is presented. Comparing with the full mode decision in MVC, the experimental results show that the proposed algorithm can reduce up to 78.13% on average and maximum 90.21% encoding time with a little increase in bit rates and loss in PSNR.

  10. SNL3dFace

    SciTech Connect

    Russ, Trina; Koch, Mark; Koudelka, Melissa; Peters, Ralph; Little, Charles; Boehnen, Chris; Peters, Tanya

    2007-07-20

    This software distribution contains MATLAB and C++ code to enable identity verification using 3D images that may or may not contain a texture component. The code is organized to support system performance testing and system capability demonstration through the proper configuration of the available user interface. Using specific algorithm parameters the face recognition system has been demonstrated to achieve a 96.6% verification rate (Pd) at 0.001 false alarm rate. The system computes robust facial features of a 3D normalized face using Principal Component Analysis (PCA) and Fisher Linear Discriminant Analysis (FLDA). A 3D normalized face is obtained by alighning each face, represented by a set of XYZ coordinated, to a scaled reference face using the Iterative Closest Point (ICP) algorithm. The scaled reference face is then deformed to the input face using an iterative framework with parameters that control the deformed surface regulation an rate of deformation. A variety of options are available to control the information that is encoded by the PCA. Such options include the XYZ coordinates, the difference of each XYZ coordinates from the reference, the Z coordinate, the intensity/texture values, etc. In addition to PCA/FLDA feature projection this software supports feature matching to obtain similarity matrices for performance analysis. In addition, this software supports visualization of the STL, MRD, 2D normalized, and PCA synthetic representations in a 3D environment.

  11. 3D and Education

    NASA Astrophysics Data System (ADS)

    Meulien Ohlmann, Odile

    2013-02-01

    Today the industry offers a chain of 3D products. Learning to "read" and to "create in 3D" becomes an issue of education of primary importance. 25 years professional experience in France, the United States and Germany, Odile Meulien set up a personal method of initiation to 3D creation that entails the spatial/temporal experience of the holographic visual. She will present some different tools and techniques used for this learning, their advantages and disadvantages, programs and issues of educational policies, constraints and expectations related to the development of new techniques for 3D imaging. Although the creation of display holograms is very much reduced compared to the creation of the 90ies, the holographic concept is spreading in all scientific, social, and artistic activities of our present time. She will also raise many questions: What means 3D? Is it communication? Is it perception? How the seeing and none seeing is interferes? What else has to be taken in consideration to communicate in 3D? How to handle the non visible relations of moving objects with subjects? Does this transform our model of exchange with others? What kind of interaction this has with our everyday life? Then come more practical questions: How to learn creating 3D visualization, to learn 3D grammar, 3D language, 3D thinking? What for? At what level? In which matter? for whom?

  12. Static & Dynamic Response of 3D Solids

    SciTech Connect

    Lin, Jerry

    1996-07-15

    NIKE3D is a large deformations 3D finite element code used to obtain the resulting displacements and stresses from multi-body static and dynamic structural thermo-mechanics problems with sliding interfaces. Many nonlinear and temperature dependent constitutive models are available.

  13. Toroidal Electromagnetic Particle-in-Cell Code with Gyro-kinetic Electron and Fully-kinetic ion

    NASA Astrophysics Data System (ADS)

    Lin, Jingbo; Zhang, Wenlu; Liu, Pengfei; Li, Ding

    2016-10-01

    A kinetic simulation model has been developed using gyro-kinetic electron and fully-kinetic ion by removing fast gyro motion of electrons using the Lie-transform perturbation theory. A particle-in-cell kinetic code is developed based on this model in general magnetic flux coordinate systems, which is particularly suitable for simulations of toroidally confined plasma. Single particle motion and field solver are successfully verified respectively. Integrated electrostatic benchmark, for example the lower-hybrid wave (LHW) and ion Bernstein wave (IBW), shows a good agreement with theoretical results. Preliminary electromagnetic benchmark of fast wave at lower hybrid frequency range is also presented. This code can be a first-principal tool to investigate high frequency nonlinear phenomenon, such as parametric decay instability, during lower-hybrid current drive (LHCD) and ion cyclotron radio frequency heating (ICRF) with complex geometry effect included. Supported by National Special Research Program of China For ITER and National Natural Science Foundation of China.

  14. 3D Imaging.

    ERIC Educational Resources Information Center

    Hastings, S. K.

    2002-01-01

    Discusses 3 D imaging as it relates to digital representations in virtual library collections. Highlights include X-ray computed tomography (X-ray CT); the National Science Foundation (NSF) Digital Library Initiatives; output peripherals; image retrieval systems, including metadata; and applications of 3 D imaging for libraries and museums. (LRW)

  15. 3D Printed Terahertz Focusing Grating Couplers

    NASA Astrophysics Data System (ADS)

    Jahn, David; Weidenbach, Marcel; Lehr, Jannik; Becker, Leonard; Beltrán-Mejía, Felipe; Busch, Stefan F.; Balzer, Jan C.; Koch, Martin

    2017-02-01

    We have designed, constructed and characterized a grating that focuses electromagnetic radiation at specific frequencies out of a dielectric waveguide. A simple theoretical model predicts the focusing behaviour of these chirped gratings, along with numerical results that support our assumptions and improved the grating geometry. The leaky waveguide was 3D printed and characterized at 120 GHz demonstrating its potential for manipulating terahertz waves.

  16. Molecular evolution of VP3, VP1, 3C(pro) and 3D(pol) coding regions in coxsackievirus group A type 24 variant isolates from acute hemorrhagic conjunctivitis in 2011 in Okinawa, Japan.

    PubMed

    Nidaira, Minoru; Kuba, Yumani; Saitoh, Mika; Taira, Katsuya; Maeshiro, Noriyuki; Mahoe, Yoko; Kyan, Hisako; Takara, Taketoshi; Okano, Sho; Kudaka, Jun; Yoshida, Hiromu; Oishi, Kazunori; Kimura, Hirokazu

    2014-04-01

    A large acute hemorrhagic conjunctivitis (AHC) outbreak occurred in 2011 in Okinawa Prefecture in Japan. Ten strains of coxsackievirus group A type 24 variant (CA24v) were isolated from patients with AHC and full sequence analysis of the VP3, VP1, 3C(pro) and 3D(pol) coding regions performed. To assess time-scale evolution, phylogenetic analysis was performed using the Bayesian Markov chain Monte Carlo method. In addition, similarity plots were constructed and pairwise distance (p-distance) and positive pressure analyses performed. A phylogenetic tree based on the VP1 coding region showed that the present strains belong to genotype 4 (G4). In addition, the present strains could have divided in about 2010 from the same lineages detected in other countries such as China, India and Australia. The mean rates of molecular evolution of four coding regions were estimated at about 6.15 to 7.86 × 10(-3) substitutions/site/year. Similarity plot analyses suggested that nucleotide similarities between the present strains and a prototype strain (EH24/70 strain) were 0.77-0.94. The p-distance of the present strains was relatively short (<0.01). Only one positive selected site (L25H) was identified in the VP1 protein. These findings suggest that the present CA24v strains causing AHC are genetically related to other AHC strains with rapid evolution and emerged in around 2010.

  17. An Improved Version of TOPAZ 3D

    SciTech Connect

    Krasnykh, Anatoly

    2003-07-29

    An improved version of the TOPAZ 3D gun code is presented as a powerful tool for beam optics simulation. In contrast to the previous version of TOPAZ 3D, the geometry of the device under test is introduced into TOPAZ 3D directly from a CAD program, such as Solid Edge or AutoCAD. In order to have this new feature, an interface was developed, using the GiD software package as a meshing code. The article describes this method with two models to illustrate the results.

  18. Explicit 3-D Hydrodynamic FEM Program

    SciTech Connect

    2000-11-07

    DYNA3D is a nonlinear explicit finite element code for analyzing 3-D structures and solid continuum. The code is vectorized and available on several computer platforms. The element library includes continuum, shell, beam, truss and spring/damper elements to allow maximum flexibility in modeling physical problems. Many materials 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, single surface contact and automatic contact generation.

  19. 3-D transient analysis of pebble-bed HTGR by TORT-TD/ATTICA3D

    SciTech Connect

    Seubert, A.; Sureda, A.; Lapins, J.; Buck, M.; Bader, J.; Laurien, E.

    2012-07-01

    As most of the acceptance criteria are local core parameters, application of transient 3-D fine mesh neutron transport and thermal hydraulics coupled codes is mandatory for best estimate evaluations of safety margins. This also applies to high-temperature gas cooled reactors (HTGR). Application of 3-D fine-mesh transient transport codes using few energy groups coupled with 3-D thermal hydraulics codes becomes feasible in view of increasing computing power. This paper describes the discrete ordinates based coupled code system TORT-TD/ATTICA3D that has recently been extended by a fine-mesh diffusion solver. Based on transient analyses for the PBMR-400 design, the transport/diffusion capabilities are demonstrated and 3-D local flux and power redistribution effects during a partial control rod withdrawal are shown. (authors)

  20. Electromagnetic self-consistent field initialization and fluid advance techniques for hybrid-kinetic PWFA code Architect

    NASA Astrophysics Data System (ADS)

    Massimo, F.; Marocchino, A.; Rossi, A. R.

    2016-09-01

    The realization of Plasma Wakefield Acceleration experiments with high quality of the accelerated bunches requires an increasing number of numerical simulations to perform first-order assessments for the experimental design and online-analysis of the experimental results. Particle in Cell codes are the state-of-the-art tools to study the beam-plasma interaction mechanism, but due to their requirements in terms of number of cores and computational time makes them unsuitable for quick parametric scans. Considerable interest has been shown thus in methods which reduce the computational time needed for the simulation of plasma acceleration. Such methods include the use of hybrid kinetic-fluid models, which treat the relativistic bunches as in a PIC code and the background plasma electrons as a fluid. A technique to properly initialize the bunch electromagnetic fields in the time explicit hybrid kinetic-fluid code Architect is presented, as well the implementation of the Flux Corrected Transport scheme for the fluid equations integrated in the code.

  1. BEAMS3D Neutral Beam Injection Model

    SciTech Connect

    Lazerson, Samuel

    2014-04-14

    With the advent of applied 3D fi elds in Tokamaks and modern high performance stellarators, a need has arisen to address non-axisymmetric effects on neutral beam heating and fueling. We report on the development of a fully 3D neutral beam injection (NBI) model, BEAMS3D, which addresses this need by coupling 3D equilibria to a guiding center code capable of modeling neutral and charged particle trajectories across the separatrix and into the plasma core. Ionization, neutralization, charge-exchange, viscous velocity reduction, and pitch angle scattering are modeled with the ADAS atomic physics database [1]. Benchmark calculations are presented to validate the collisionless particle orbits, neutral beam injection model, frictional drag, and pitch angle scattering effects. A calculation of neutral beam heating in the NCSX device is performed, highlighting the capability of the code to handle 3D magnetic fields.

  2. CASTOR3D: linear stability studies for 2D and 3D tokamak equilibria

    NASA Astrophysics Data System (ADS)

    Strumberger, E.; Günter, S.

    2017-01-01

    The CASTOR3D code, which is currently under development, is able to perform linear stability studies for 2D and 3D, ideal and resistive tokamak equilibria in the presence of ideal and resistive wall structures and coils. For these computations ideal equilibria represented by concentric nested flux surfaces serve as input (e.g. computed with the NEMEC code). Solving an extended eigenvalue problem, the CASTOR3D code takes simultaneously plasma inertia and wall resistivity into account. The code is a hybrid of the CASTOR_3DW stability code and the STARWALL code. The former is an extended version of the CASTOR and CASTOR_FLOW code, respectively. The latter is a linear 3D code computing the growth rates of resistive wall modes in the presence of multiply-connected wall structures. The CASTOR_3DW code, and some parts of the STARWALL code have been reformulated in a general 3D flux coordinate representation that allows to choose between various types of flux coordinates. Furthermore, the implemented many-valued current potentials in the STARWALL part allow a correct treatment of the m  =  0, n  =  0 perturbation. In this paper, we outline the theoretical concept, and present some numerical results which illustrate the present status of the code and demonstrate its numerous application possibilities.

  3. Ex-vessel neutron dosimetry analysis for westinghouse 4-loop XL pressurized water reactor plant using the RadTrack{sup TM} Code System with the 3D parallel discrete ordinates code RAPTOR-M3G

    SciTech Connect

    Chen, J.; Alpan, F. A.; Fischer, G.A.; Fero, A.H.

    2011-07-01

    Traditional two-dimensional (2D)/one-dimensional (1D) SYNTHESIS methodology has been widely used to calculate fast neutron (>1.0 MeV) fluence exposure to reactor pressure vessel in the belt-line region. However, it is expected that this methodology cannot provide accurate fast neutron fluence calculation at elevations far above or below the active core region. A three-dimensional (3D) parallel discrete ordinates calculation for ex-vessel neutron dosimetry on a Westinghouse 4-Loop XL Pressurized Water Reactor has been done. It shows good agreement between the calculated results and measured results. Furthermore, the results show very different fast neutron flux values at some of the former plate locations and elevations above and below an active core than those calculated by a 2D/1D SYNTHESIS method. This indicates that for certain irregular reactor internal structures, where the fast neutron flux has a very strong local effect, it is required to use a 3D transport method to calculate accurate fast neutron exposure. (authors)

  4. Comparison of Computational Electromagnetic Codes for Prediction of Low-Frequency Radar Cross Section

    DTIC Science & Technology

    2006-03-01

    plate ............ 2-49 Figure 2-22: Surface -guided wave in a material........................................................... 2-50 Figure 2-23...Lossy Surfaces (CARLOS-3D), and Science Applications International Corporation (SAIC) Full- wave solver (SAF). Obtaining RCS data can be accomplished...is transverse to the z-coordinate direction, and is referred to as TEMZ. 2.10 Plane Wave Polarization Consider a plane wave upon a planar surface

  5. AE3D

    SciTech Connect

    Spong, Donald A

    2016-06-20

    AE3D solves for the shear Alfven eigenmodes and eigenfrequencies in a torodal magnetic fusion confinement device. The configuration can be either 2D (e.g. tokamak, reversed field pinch) or 3D (e.g. stellarator, helical reversed field pinch, tokamak with ripple). The equations solved are based on a reduced MHD model and sound wave coupling effects are not currently included.

  6. Use of generalized curvilinear coordinate systems in electromagnetic and hybrid codes

    SciTech Connect

    Swift, D.W.

    1995-07-01

    The author develops a code to simulate the dynamics in the magnetosphere system. The calculation involves a single level, structured, curvilinear 2D mesh. The mesh density is varied to support regions which demand higher resolution.

  7. 3-D Finite Element Code Postprocessor

    SciTech Connect

    1996-07-15

    TAURUS is an interactive post-processing application supporting visualization of finite element analysis results on unstructured grids. TAURUS provides the ability to display deformed geometries and contours or fringes of a large number of derived results on meshes consisting of beam, plate, shell, and solid type finite elements. Time history plotting is also available.

  8. Application of Advanced Concepts and Techniques in Electromagnetic Topology Based Simulations: CRIPTE and Related Codes

    DTIC Science & Technology

    2008-12-01

    simulation validation process. The experimental setup used to study the interaction of the electromagnetic field with an aperture is seen in Fig. IVA -1. The...distance of 3 meters from the metallic plate to satisfy the far field condition at low frequencies. Semi-anechoic Chamber Fig. IVA -1 Experiment setup...transfer function is then calculated from recored electric fields as follows. Hani") ’trans,all {co)-Eu (co) "/’ EM ( IVA -1) where H^a)) is the

  9. NUBEAM developments and 3d halo modeling

    NASA Astrophysics Data System (ADS)

    Gorelenkova, M. V.; Medley, S. S.; Kaye, S. M.

    2012-10-01

    Recent developments related to the 3D halo model in NUBEAM code are described. To have a reliable halo neutral source for diagnostic simulation, the TRANSP/NUBEAM code has been enhanced with full implementation of ADAS atomic physic ground state and excited state data for hydrogenic beams and mixed species plasma targets. The ADAS codes and database provide the density and temperature dependence of the atomic data, and the collective nature of the state excitation process. To be able to populate 3D halo output with sufficient statistical resolution, the capability to control the statistics of fast ion CX modeling and for thermal halo launch has been added to NUBEAM. The 3D halo neutral model is based on modification and extension of the ``beam in box'' aligned 3d Cartesian grid that includes the neutral beam itself, 3D fast neutral densities due to CX of partially slowed down fast ions in the beam halo region, 3D thermal neutral densities due to CX deposition and fast neutral recapture source. More details on the 3D halo simulation design will be presented.

  10. 3-D Seismic Interpretation

    NASA Astrophysics Data System (ADS)

    Moore, Gregory F.

    2009-05-01

    This volume is a brief introduction aimed at those who wish to gain a basic and relatively quick understanding of the interpretation of three-dimensional (3-D) seismic reflection data. The book is well written, clearly illustrated, and easy to follow. Enough elementary mathematics are presented for a basic understanding of seismic methods, but more complex mathematical derivations are avoided. References are listed for readers interested in more advanced explanations. After a brief introduction, the book logically begins with a succinct chapter on modern 3-D seismic data acquisition and processing. Standard 3-D acquisition methods are presented, and an appendix expands on more recent acquisition techniques, such as multiple-azimuth and wide-azimuth acquisition. Although this chapter covers the basics of standard time processing quite well, there is only a single sentence about prestack depth imaging, and anisotropic processing is not mentioned at all, even though both techniques are now becoming standard.

  11. Radiochromic 3D Detectors

    NASA Astrophysics Data System (ADS)

    Oldham, Mark

    2015-01-01

    Radiochromic materials exhibit a colour change when exposed to ionising radiation. Radiochromic film has been used for clinical dosimetry for many years and increasingly so recently, as films of higher sensitivities have become available. The two principle advantages of radiochromic dosimetry include greater tissue equivalence (radiologically) and the lack of requirement for development of the colour change. In a radiochromic material, the colour change arises direct from ionising interactions affecting dye molecules, without requiring any latent chemical, optical or thermal development, with important implications for increased accuracy and convenience. It is only relatively recently however, that 3D radiochromic dosimetry has become possible. In this article we review recent developments and the current state-of-the-art of 3D radiochromic dosimetry, and the potential for a more comprehensive solution for the verification of complex radiation therapy treatments, and 3D dose measurement in general.

  12. Bootstrapping 3D fermions

    DOE PAGES

    Iliesiu, Luca; Kos, Filip; Poland, David; ...

    2016-03-17

    We study the conformal bootstrap for a 4-point function of fermions <ψψψψ> in 3D. We first introduce an embedding formalism for 3D spinors and compute the conformal blocks appearing in fermion 4-point functions. Using these results, we find general bounds on the dimensions of operators appearing in the ψ × ψ OPE, and also on the central charge CT. We observe features in our bounds that coincide with scaling dimensions in the GrossNeveu models at large N. Finally, we also speculate that other features could coincide with a fermionic CFT containing no relevant scalar operators.

  13. Bootstrapping 3D fermions

    SciTech Connect

    Iliesiu, Luca; Kos, Filip; Poland, David; Pufu, Silviu S.; Simmons-Duffin, David; Yacoby, Ran

    2016-03-17

    We study the conformal bootstrap for a 4-point function of fermions <ψψψψ> in 3D. We first introduce an embedding formalism for 3D spinors and compute the conformal blocks appearing in fermion 4-point functions. Using these results, we find general bounds on the dimensions of operators appearing in the ψ × ψ OPE, and also on the central charge CT. We observe features in our bounds that coincide with scaling dimensions in the GrossNeveu models at large N. Finally, we also speculate that other features could coincide with a fermionic CFT containing no relevant scalar operators.

  14. 3D parallel inversion of time-domain airborne EM data

    NASA Astrophysics Data System (ADS)

    Liu, Yun-He; Yin, Chang-Chun; Ren, Xiu-Yan; Qiu, Chang-Kai

    2016-12-01

    To improve the inversion accuracy of time-domain airborne electromagnetic data, we propose a parallel 3D inversion algorithm for airborne EM data based on the direct Gauss-Newton optimization. Forward modeling is performed in the frequency domain based on the scattered secondary electrical field. Then, the inverse Fourier transform and convolution of the transmitting waveform are used to calculate the EM responses and the sensitivity matrix in the time domain for arbitrary transmitting waves. To optimize the computational time and memory requirements, we use the EM "footprint" concept to reduce the model size and obtain the sparse sensitivity matrix. To improve the 3D inversion, we use the OpenMP library and parallel computing. We test the proposed 3D parallel inversion code using two synthetic datasets and a field dataset. The time-domain airborne EM inversion results suggest that the proposed algorithm is effective, efficient, and practical.

  15. Accelerating a 3D finite-difference wave propagation code by a factor of 50 and a spectral-element code by a factor of 25 using a cluster of GPU graphics cards

    NASA Astrophysics Data System (ADS)

    Komatitsch, Dimitri; Michéa, David; Erlebacher, Gordon; Göddeke, Dominik

    2010-05-01

    We first accelerate a three-dimensional finite-difference in the time domain (FDTD) wave propagation code by a factor of about 50 using Graphics Processing Unit (GPU) computing on a cheap NVIDIA graphics card with the CUDA programming language. We implement the code in CUDA in the case of the fully heterogeneous elastic wave equation. We also implement Convolution Perfectly Matched Layers (CPMLs) on the graphics card to efficiently absorb outgoing waves on the fictitious edges of the grid. We show that the code that runs on the graphics card gives the expected results by comparing our results to those obtained by running the same simulation on a classical processor core. The methodology that we present can be used for Maxwell's equations as well because their form is similar to that of the seismic wave equation written in velocity vector and stress tensor. We then implement a high-order finite-element (spectral-element) application, which performs the numerical simulation of seismic wave propagation resulting for instance from earthquakes at the scale of a continent or from active seismic acquisition experiments in the oil industry, on a cluster of NVIDIA Tesla graphics cards using the CUDA programming language and non blocking message passing based on MPI. We compare it to the implementation in C language and MPI on a classical cluster of CPU nodes. We use mesh coloring to efficiently handle summation operations over degrees of freedom on an unstructured mesh, and we exchange information between nodes using non blocking MPI messages. Using non-blocking communications allows us to overlap the communications across the network and the data transfer between the GPU card and the CPU node on which it is installed with calculations on that GPU card. We perform a number of numerical tests to validate the single-precision CUDA and MPI implementation and assess its accuracy. We then analyze performance measurements and in average we obtain a speedup of 20x to 25x.

  16. NIKE3D96. Static & Dynamic Response of 3D Solids

    SciTech Connect

    Maker, B.; Hallquist, J.O.; Ferencz, R.M.

    1991-02-01

    NIKE3D is a large deformations 3D finite element code used to obtain the resulting displacements and stresses from multi-body static and dynamic structural thermo-mechanics problems with sliding interfaces. Many nonlinear and temperature dependent constitutive models are available.

  17. Wakefield Simulation of CLIC PETS Structure Using Parallel 3D Finite Element Time-Domain Solver T3P

    SciTech Connect

    Candel, A.; Kabel, A.; Lee, L.; Li, Z.; Ng, C.; Schussman, G.; Ko, K.; Syratchev, I.; /CERN

    2009-06-19

    In recent years, SLAC's Advanced Computations Department (ACD) has developed the parallel 3D Finite Element electromagnetic time-domain code T3P. Higher-order Finite Element methods on conformal unstructured meshes and massively parallel processing allow unprecedented simulation accuracy for wakefield computations and simulations of transient effects in realistic accelerator structures. Applications include simulation of wakefield damping in the Compact Linear Collider (CLIC) power extraction and transfer structure (PETS).

  18. Venus in 3D

    NASA Technical Reports Server (NTRS)

    Plaut, Jeffrey J.

    1993-01-01

    Stereographic images of the surface of Venus which enable geologists to reconstruct the details of the planet's evolution are discussed. The 120-meter resolution of these 3D images make it possible to construct digital topographic maps from which precise measurements can be made of the heights, depths, slopes, and volumes of geologic structures.

  19. 3D photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Carson, Jeffrey J. L.; Roumeliotis, Michael; Chaudhary, Govind; Stodilka, Robert Z.; Anastasio, Mark A.

    2010-06-01

    Our group has concentrated on development of a 3D photoacoustic imaging system for biomedical imaging research. The technology employs a sparse parallel detection scheme and specialized reconstruction software to obtain 3D optical images using a single laser pulse. With the technology we have been able to capture 3D movies of translating point targets and rotating line targets. The current limitation of our 3D photoacoustic imaging approach is its inability ability to reconstruct complex objects in the field of view. This is primarily due to the relatively small number of projections used to reconstruct objects. However, in many photoacoustic imaging situations, only a few objects may be present in the field of view and these objects may have very high contrast compared to background. That is, the objects have sparse properties. Therefore, our work had two objectives: (i) to utilize mathematical tools to evaluate 3D photoacoustic imaging performance, and (ii) to test image reconstruction algorithms that prefer sparseness in the reconstructed images. Our approach was to utilize singular value decomposition techniques to study the imaging operator of the system and evaluate the complexity of objects that could potentially be reconstructed. We also compared the performance of two image reconstruction algorithms (algebraic reconstruction and l1-norm techniques) at reconstructing objects of increasing sparseness. We observed that for a 15-element detection scheme, the number of measureable singular vectors representative of the imaging operator was consistent with the demonstrated ability to reconstruct point and line targets in the field of view. We also observed that the l1-norm reconstruction technique, which is known to prefer sparseness in reconstructed images, was superior to the algebraic reconstruction technique. Based on these findings, we concluded (i) that singular value decomposition of the imaging operator provides valuable insight into the capabilities of

  20. Model Development and Verification of the CRIPTE Code for Electromagnetic Coupling

    DTIC Science & Technology

    2005-10-01

    Fig. IIIC-2 (a) TLM equivalent for a shunt node and (b) Topological node representing the TLM mesh node. This shows the slow-wave property of the 2-D...inherent high-pass filtering properties . Incrementing the aperture size also results in the cutoff frequency to shift lower, allowing more penetration...approached. In addition, the delay of the wave from the EMT code reflects the property of the slow-wave 42 Model Development and Verification of the CRIPTE

  1. Restructuring of RELAP5-3D

    SciTech Connect

    George Mesina; Joshua Hykes

    2005-09-01

    The RELAP5-3D source code is unstructured with many interwoven logic flow paths. By restructuring the code, it becomes easier to read and understand, which reduces the time and money required for code development, debugging, and maintenance. A structured program is comprised of blocks of code with one entry and exit point and downward logic flow. IF tests and DO loops inherently create structured code, while GOTO statements are the main cause of unstructured code. FOR_STRUCT is a commercial software package that converts unstructured FORTRAN into structured programming; it was used to restructure individual subroutines. Primarily it transforms GOTO statements, ARITHMETIC IF statements, and COMPUTED GOTO statements into IF-ELSEIF-ELSE tests and DO loops. The complexity of RELAP5-3D complicated the task. First, FOR_STRUCT cannot completely restructure all the complex coding contained in RELAP5-3D. An iterative approach of multiple FOR_STRUCT applications gave some additional improvements. Second, FOR_STRUCT cannot restructure FORTRAN 90 coding, and RELAP5-3D is partially written in FORTRAN 90. Unix scripts for pre-processing subroutines into coding that FOR_STRUCT could handle and post-processing it back into FORTRAN 90 were written. Finally, FOR_STRUCT does not have the ability to restructure the RELAP5-3D code which contains pre-compiler directives. Variations of a file were processed with different pre-compiler options switched on or off, ensuring that every block of code was restructured. Then the variations were recombined to create a completely restructured source file. Unix scripts were written to perform these tasks, as well as to make some minor formatting improvements. In total, 447 files comprising some 180,000 lines of FORTRAN code were restructured. These showed significant reduction in the number of logic jumps contained as measured by reduction in the number of GOTO statements and line labels. The average number of GOTO statements per subroutine

  2. 3-D physical models of amitosis (cytokinesis).

    PubMed

    Cheng, Kang; Zou, Changhua

    2005-01-01

    Based on Newton's laws, extended Coulomb's law and published biological data, we develop our 3-D physical models of natural and normal amitosis (cytokinesis), for prokaryotes (bacterial cells) in M phase. We propose following hypotheses: Chromosome rings exclusion: No normally and naturally replicated chromosome rings (RCR) can occupy the same prokaryote, a bacterial cell. The RCR produce spontaneous and strong electromagnetic fields (EMF), that can be alternated environmentally, in protoplasm and cortex. The EMF is approximately a repulsive quasi-static electric (slowly variant and mostly electric) field (EF). The EF forces between the RCR are strong enough, and orderly accumulate contractile proteins that divide the procaryotes in the cell cortex of division plane or directly split the cell compartment envelope longitudinally. The radial component of the EF forces could also make furrows or cleavages of procaryotes. The EF distribution controls the protoplasm partition and completes the amitosis (cytokinesis). After the cytokinesis, the spontaneous and strong EF disappear because the net charge accumulation becomes weak, in the protoplasm. The exclusion is because the two sets of informative objects (RCR) have identical DNA codes information and they are electro magnetically identical, therefore they repulse from each other. We also compare divisions among eukaryotes, prokaryotes, mitochondria and chloroplasts and propose our hypothesis: The principles of our models are applied to divisions of mitochondria and chloroplasts of eucaryotes too because these division mechanisms are closer than others in a view of physics. Though we develop our model using 1 division plane (i.e., 1 cell is divided into 2 cells) as an example, the principle of our model is applied to the cases with multiple division planes (i.e., 1 cell is divided into multiple cells) too.

  3. Benchmarking the GENE and GYRO codes through the relative roles of electromagnetic and E  ×  B stabilization in JET high-performance discharges

    NASA Astrophysics Data System (ADS)

    Bravenec, R.; Citrin, J.; Candy, J.; Mantica, P.; Görler, T.; contributors, JET

    2016-12-01

    Nonlinear gyrokinetic simulations using the GENE code have previously predicted a significant nonlinear enhanced electromagnetic stabilization in certain JET discharges with high neutral-beam power and low core magnetic shear (Citrin et al 2013 Phys. Rev. Lett. 111 155001, 2015 Plasma Phys. Control. Fusion 57 014032). This dominates over the impact of E  ×  B flow shear in these discharges. Furthermore, fast ions were shown to be a major contributor to the electromagnetic stabilization. These conclusions were based on results from the GENE gyrokinetic turbulence code. In this work we verify these results using the GYRO code. Comparing results (linear frequencies, eigenfunctions, and nonlinear fluxes) from different gyrokinetic codes as a means of verification (benchmarking) is only convincing if the codes agree for more than one discharge. Otherwise, agreement may simply be fortuitous. Therefore, we analyze three discharges, all with a carbon wall: a simplified, two-species, circular geometry case based on an actual JET discharge; an L-mode discharge with a significant fast-ion pressure fraction; and a low-triangularity high-β hybrid discharge. All discharges were analyzed at normalized toroidal flux coordinate ρ  =  0.33 where significant ion temperature peaking is observed. The GYRO simulations support the conclusion that electromagnetic stabilization is strong, and dominates E  ×  B shear stabilization.

  4. Twin Peaks - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The two hills in the distance, approximately one to two kilometers away, have been dubbed the 'Twin Peaks' and are of great interest to Pathfinder scientists as objects of future study. 3D glasses are necessary to identify surface detail. The white areas on the left hill, called the 'Ski Run' by scientists, may have been formed by hydrologic processes.

    The IMP is a stereo imaging system with color capability provided by 24 selectable filters -- twelve filters per 'eye.

    Click below to see the left and right views individually. [figure removed for brevity, see original site] Left [figure removed for brevity, see original site] Right

  5. 3D and beyond

    NASA Astrophysics Data System (ADS)

    Fung, Y. C.

    1995-05-01

    This conference on physiology and function covers a wide range of subjects, including the vasculature and blood flow, the flow of gas, water, and blood in the lung, the neurological structure and function, the modeling, and the motion and mechanics of organs. Many technologies are discussed. I believe that the list would include a robotic photographer, to hold the optical equipment in a precisely controlled way to obtain the images for the user. Why are 3D images needed? They are to achieve certain objectives through measurements of some objects. For example, in order to improve performance in sports or beauty of a person, we measure the form, dimensions, appearance, and movements.

  6. 3D Audio System

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Ames Research Center research into virtual reality led to the development of the Convolvotron, a high speed digital audio processing system that delivers three-dimensional sound over headphones. It consists of a two-card set designed for use with a personal computer. The Convolvotron's primary application is presentation of 3D audio signals over headphones. Four independent sound sources are filtered with large time-varying filters that compensate for motion. The perceived location of the sound remains constant. Possible applications are in air traffic control towers or airplane cockpits, hearing and perception research and virtual reality development.

  7. Magmatic Systems in 3-D

    NASA Astrophysics Data System (ADS)

    Kent, G. M.; Harding, A. J.; Babcock, J. M.; Orcutt, J. A.; Bazin, S.; Singh, S.; Detrick, R. S.; Canales, J. P.; Carbotte, S. M.; Diebold, J.

    2002-12-01

    Multichannel seismic (MCS) images of crustal magma chambers are ideal targets for advanced visualization techniques. In the mid-ocean ridge environment, reflections originating at the melt-lens are well separated from other reflection boundaries, such as the seafloor, layer 2A and Moho, which enables the effective use of transparency filters. 3-D visualization of seismic reflectivity falls into two broad categories: volume and surface rendering. Volumetric-based visualization is an extremely powerful approach for the rapid exploration of very dense 3-D datasets. These 3-D datasets are divided into volume elements or voxels, which are individually color coded depending on the assigned datum value; the user can define an opacity filter to reject plotting certain voxels. This transparency allows the user to peer into the data volume, enabling an easy identification of patterns or relationships that might have geologic merit. Multiple image volumes can be co-registered to look at correlations between two different data types (e.g., amplitude variation with offsets studies), in a manner analogous to draping attributes onto a surface. In contrast, surface visualization of seismic reflectivity usually involves producing "fence" diagrams of 2-D seismic profiles that are complemented with seafloor topography, along with point class data, draped lines and vectors (e.g. fault scarps, earthquake locations and plate-motions). The overlying seafloor can be made partially transparent or see-through, enabling 3-D correlations between seafloor structure and seismic reflectivity. Exploration of 3-D datasets requires additional thought when constructing and manipulating these complex objects. As numbers of visual objects grow in a particular scene, there is a tendency to mask overlapping objects; this clutter can be managed through the effective use of total or partial transparency (i.e., alpha-channel). In this way, the co-variation between different datasets can be investigated

  8. 3D Surgical Simulation

    PubMed Central

    Cevidanes, Lucia; Tucker, Scott; Styner, Martin; Kim, Hyungmin; Chapuis, Jonas; Reyes, Mauricio; Proffit, William; Turvey, Timothy; Jaskolka, Michael

    2009-01-01

    This paper discusses the development of methods for computer-aided jaw surgery. Computer-aided jaw surgery allows us to incorporate the high level of precision necessary for transferring virtual plans into the operating room. We also present a complete computer-aided surgery (CAS) system developed in close collaboration with surgeons. Surgery planning and simulation include construction of 3D surface models from Cone-beam CT (CBCT), dynamic cephalometry, semi-automatic mirroring, interactive cutting of bone and bony segment repositioning. A virtual setup can be used to manufacture positioning splints for intra-operative guidance. The system provides further intra-operative assistance with the help of a computer display showing jaw positions and 3D positioning guides updated in real-time during the surgical procedure. The CAS system aids in dealing with complex cases with benefits for the patient, with surgical practice, and for orthodontic finishing. Advanced software tools for diagnosis and treatment planning allow preparation of detailed operative plans, osteotomy repositioning, bone reconstructions, surgical resident training and assessing the difficulties of the surgical procedures prior to the surgery. CAS has the potential to make the elaboration of the surgical plan a more flexible process, increase the level of detail and accuracy of the plan, yield higher operative precision and control, and enhance documentation of cases. Supported by NIDCR DE017727, and DE018962 PMID:20816308

  9. Martian terrain - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    An area of rocky terrain near the landing site of the Sagan Memorial Station can be seen in this image, taken in stereo by the Imager for Mars Pathfinder (IMP) on Sol 3. 3D glasses are necessary to identify surface detail. This image is part of a 3D 'monster' panorama of the area surrounding the landing site.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

    Click below to see the left and right views individually. [figure removed for brevity, see original site] Left [figure removed for brevity, see original site] Right

  10. Recent improvements to the ASTRA particle tracking code

    SciTech Connect

    Flottmann, Klaus; Lidia, Steven; Piot, Philippe

    2003-05-19

    The Astra simulation code has been successfully used in the design of linac and rf photoinjector systems utilizing beams with azimuthal symmetry. We present recently implemented changes to Astra that allow tracking of beams in beamlines without the assumption of any symmetry. The changes especially include a 3D mesh space charge algorithm and the possibility to import 3D electromagnetic fieldmaps from eigensolver programs.

  11. 3D Simulation: Microgravity Environments and Applications

    NASA Technical Reports Server (NTRS)

    Hunter, Steve L.; Dischinger, Charles; Estes, Samantha; Parker, Nelson C. (Technical Monitor)

    2001-01-01

    Most, if not all, 3-D and Virtual Reality (VR) software programs are designed for one-G gravity applications. Space environments simulations require gravity effects of one one-thousandth to one one-million of that of the Earth's surface (10(exp -3) - 10(exp -6) G), thus one must be able to generate simulations that replicate those microgravity effects upon simulated astronauts. Unfortunately, the software programs utilized by the National Aeronautical and Space Administration does not have the ability to readily neutralize the one-G gravity effect. This pre-programmed situation causes the engineer or analysis difficulty during micro-gravity simulations. Therefore, microgravity simulations require special techniques or additional code in order to apply the power of 3D graphic simulation to space related applications. This paper discusses the problem and possible solutions to allow microgravity 3-D/VR simulations to be completed successfully without program code modifications.

  12. Unidirectional transparent signal injection in finite-difference time-domain electromagnetic codes -application to reflectometry simulations

    SciTech Connect

    Silva, F. da; Hacquin, S.

    2005-03-01

    We present a novel numerical signal injection technique allowing unidirectional injection of a wave in a wave-guiding structure, applicable to 2D finite-difference time-domain electromagnetic codes, both Maxwell and wave-equation. It is particularly suited to continuous wave radar-like simulations. The scheme gives an unidirectional injection of a signal while being transparent to waves propagating in the opposite direction (directional coupling). The reflected or backscattered waves (returned) are separated from the probing waves allowing direct access to the information on amplitude and phase of the returned wave. It also facilitates the signal processing used to extract the phase derivative (or group delay) when simulating radar systems. Although general, the technique is particularly suited to swept frequency sources (frequency modulated) in the context of reflectometry, a fusion plasma diagnostic. The UTS applications presented here are restricted to fusion plasma reflectometry simulations for different physical situations. This method can, nevertheless, also be used in other dispersive media such as dielectrics, being useful, for example, in the simulation of plasma filled waveguides or directional couplers.

  13. Electromagnetic pulse (EMP) coupling codes for use with the vulnerability/lethality (VIL) taxonomy. Final report, June-October 1984

    SciTech Connect

    Mar, M.H.

    1995-07-01

    Based on the vulnerability Lethality (V/L) taxonomy developed by the Ballistic Vulnerability Lethality Division (BVLD) of the Survivability Lethality Analysis Directorate (SLAD), a nuclear electromagnetic pulse (EMP) coupling V/L analysis taxonomy has been developed. A nuclear EMP threat to a military system can be divided into two levels: (1) coupling to a system level through a cable, antenna, or aperture; and (2) the component level. This report will focus on the initial condition, which includes threat definition and target description, as well as the mapping process from the initial condition to damaged components state. EMP coupling analysis at a system level is used to accomplish this. This report introduces the nature of EMP threat, interaction between the threat and target, and how the output of EMP coupling analysis at a system level becomes the input to the component level analysis. Many different tools (EMP coupling codes) will be discussed for the mapping process, which correponds to the physics of phenomenology. This EMP coupling V/L taxonomy and the models identified in this report will provide the tools necessary to conduct basic V/L analysis of EMP coupling.

  14. 3-D Particle Simulation of Current Sheet Instabilities

    NASA Astrophysics Data System (ADS)

    Wang, Zhenyu; Lin, Yu; Wang, Xueyi; Tummel, Kurt; Chen, Liu

    2015-11-01

    The electrostatic (ES) and electromagnetic (EM) instabilities of a Harris current sheet are investigated using a 3-D linearized (δf) gyrokinetic (GK) electron and fully kinetic (FK) ion (GeFi) particle simulation code. The equilibrium magnetic field consists of an asymptotic anti-parallel Bx 0 and a guide field BG. The ES simulations show the excitation of lower-hybrid drift instability (LHDI) at the current sheet edge. The growth rate of the 3-D LHDI is scanned through the (kx ,ky) space. The most unstable modes are found to be at k∥ = 0 for smaller ky. As ky increases, the growth rate shows two peaks at k∥ ≠ 0 , consistent with analytical GK theory. The eigenmode structure and growth rate of LHDI obtained from the GeFi simulation agree well with those obtained from the FK PIC simulation. Decreasing BG, the asymptotic βe 0, or background density can destabilize the LHDI. In the EM simulation, tearing mode instability is dominant in the cases with ky kx , there exist two unstable modes: a kink-like (LHDI) mode at the current sheet edge and a sausage-like mode at the sheet center. The results are compared with the GK eigenmode theory and the FK simulation.

  15. Electromagnetic plasma simulation in realistic geometries

    SciTech Connect

    Brandon, S.; Ambrosiano, J.; Nielsen, D.

    1991-08-01

    Particle-in-Cell (PIC) calculations have become an indispensable tool to model the nonlinear collective behavior of charged particle species in electromagnetic fields. Traditional finite difference codes, such as CONDOR (2-D) and ARGUS (3-D), are used extensively to design experiments and develop new concepts. A wide variety of physical processes can be modeled simply and efficiently by these codes. However, experiments have become more complex. Geometrical shapes and length scales are becoming increasingly more difficult to model. Spatial resolution requirements for the electromagnetic calculation force large grids and small time steps. Many hours of CRAY YMP time may be required to complete 2-D calculation -- many more for 3-D calculations. In principle, the number of mesh points and particles need only to be increased until all relevant physical processes are resolved. In practice, the size of a calculation is limited by the computer budget. As a result, experimental design is being limited by the ability to calculate, not by the experimenters ingenuity or understanding of the physical processes involved. Several approaches to meet these computational demands are being pursued. Traditional PIC codes continue to be the major design tools. These codes are being actively maintained, optimized, and extended to handle large and more complex problems. Two new formulations are being explored to relax the geometrical constraints of the finite difference codes. A modified finite volume test code, TALUS, uses a data structure compatible with that of standard finite difference meshes. This allows a basic conformal boundary/variable grid capability to be retrofitted to CONDOR. We are also pursuing an unstructured grid finite element code, MadMax. The unstructured mesh approach provides maximum flexibility in the geometrical model while also allowing local mesh refinement. Both innovative approaches to electromagnetic PIC calculations are generalizable to 3-D.

  16. Simulation of TunneLadder traveling-wave tube cold-test characteristics: Implementation of the three-dimensional, electromagnetic circuit analysis code micro-SOS

    NASA Technical Reports Server (NTRS)

    Kory, Carol L.; Wilson, Jeffrey D.

    1993-01-01

    The three-dimensional, electromagnetic circuit analysis code, Micro-SOS, can be used to reduce expensive time-consuming experimental 'cold-testing' of traveling-wave tube (TWT) circuits. The frequency-phase dispersion characteristics and beam interaction impedance of a TunneLadder traveling-wave tube slow-wave structure were simulated using the code. When reasonable dimensional adjustments are made, computer results agree closely with experimental data. Modifications to the circuit geometry that would make the TunneLadder TWT easier to fabricate for higher frequency operation are explored.

  17. BEAMS3D Neutral Beam Injection Model

    NASA Astrophysics Data System (ADS)

    McMillan, Matthew; Lazerson, Samuel A.

    2014-09-01

    With the advent of applied 3D fields in Tokamaks and modern high performance stellarators, a need has arisen to address non-axisymmetric effects on neutral beam heating and fueling. We report on the development of a fully 3D neutral beam injection (NBI) model, BEAMS3D, which addresses this need by coupling 3D equilibria to a guiding center code capable of modeling neutral and charged particle trajectories across the separatrix and into the plasma core. Ionization, neutralization, charge-exchange, viscous slowing down, and pitch angle scattering are modeled with the ADAS atomic physics database. Elementary benchmark calculations are presented to verify the collisionless particle orbits, NBI model, frictional drag, and pitch angle scattering effects. A calculation of neutral beam heating in the NCSX device is performed, highlighting the capability of the code to handle 3D magnetic fields. Notice: this manuscript has been authored by Princeton University under Contract Number DE-AC02-09CH11466 with the US Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes.

  18. Intraoral 3D scanner

    NASA Astrophysics Data System (ADS)

    Kühmstedt, Peter; Bräuer-Burchardt, Christian; Munkelt, Christoph; Heinze, Matthias; Palme, Martin; Schmidt, Ingo; Hintersehr, Josef; Notni, Gunther

    2007-09-01

    Here a new set-up of a 3D-scanning system for CAD/CAM in dental industry is proposed. The system is designed for direct scanning of the dental preparations within the mouth. The measuring process is based on phase correlation technique in combination with fast fringe projection in a stereo arrangement. The novelty in the approach is characterized by the following features: A phase correlation between the phase values of the images of two cameras is used for the co-ordinate calculation. This works contrary to the usage of only phase values (phasogrammetry) or classical triangulation (phase values and camera image co-ordinate values) for the determination of the co-ordinates. The main advantage of the method is that the absolute value of the phase at each point does not directly determine the coordinate. Thus errors in the determination of the co-ordinates are prevented. Furthermore, using the epipolar geometry of the stereo-like arrangement the phase unwrapping problem of fringe analysis can be solved. The endoscope like measurement system contains one projection and two camera channels for illumination and observation of the object, respectively. The new system has a measurement field of nearly 25mm × 15mm. The user can measure two or three teeth at one time. So the system can by used for scanning of single tooth up to bridges preparations. In the paper the first realization of the intraoral scanner is described.

  19. 'Diamond' in 3-D

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This 3-D, microscopic imager mosaic of a target area on a rock called 'Diamond Jenness' was taken after NASA's Mars Exploration Rover Opportunity ground into the surface with its rock abrasion tool for a second time.

    Opportunity has bored nearly a dozen holes into the inner walls of 'Endurance Crater.' On sols 177 and 178 (July 23 and July 24, 2004), the rover worked double-duty on Diamond Jenness. Surface debris and the bumpy shape of the rock resulted in a shallow and irregular hole, only about 2 millimeters (0.08 inch) deep. The final depth was not enough to remove all the bumps and leave a neat hole with a smooth floor. This extremely shallow depression was then examined by the rover's alpha particle X-ray spectrometer.

    On Sol 178, Opportunity's 'robotic rodent' dined on Diamond Jenness once again, grinding almost an additional 5 millimeters (about 0.2 inch). The rover then applied its Moessbauer spectrometer to the deepened hole. This double dose of Diamond Jenness enabled the science team to examine the rock at varying layers. Results from those grindings are currently being analyzed.

    The image mosaic is about 6 centimeters (2.4 inches) across.

  20. Prominent rocks - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Many prominent rocks near the Sagan Memorial Station are featured in this image, taken in stereo by the Imager for Mars Pathfinder (IMP) on Sol 3. 3D glasses are necessary to identify surface detail. Wedge is at lower left; Shark, Half-Dome, and Pumpkin are at center. Flat Top, about four inches high, is at lower right. The horizon in the distance is one to two kilometers away.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

    Click below to see the left and right views individually. [figure removed for brevity, see original site] Left [figure removed for brevity, see original site] Right

  1. CFL3D User's Manual (Version 5.0)

    NASA Technical Reports Server (NTRS)

    Krist, Sherrie L.; Biedron, Robert T.; Rumsey, Christopher L.

    1998-01-01

    This document is the User's Manual for the CFL3D computer code, a thin-layer Reynolds-averaged Navier-Stokes flow solver for structured multiple-zone grids. Descriptions of the code's input parameters, non-dimensionalizations, file formats, boundary conditions, and equations are included. Sample 2-D and 3-D test cases are also described, and many helpful hints for using the code are provided.

  2. Delft3D turbine turbulence module

    SciTech Connect

    Chartrand, Chris; Jagers, Bert

    2016-04-18

    The DOE has funded Sandia National Labs (SNL) to develop an open-source modeling tool to guide the design and layout of marine hydrokinetic (MHK) arrays to maximize power production while minimizing environmental effects. This modeling framework simulates flows through and around a MHK arrays while quantifying environmental responses. As an augmented version of the Dutch company, Deltares’s, environmental hydrodynamics code, Delft3D, SNL-Delft3D includes a new module that simulates energy conversion (momentum withdrawal) by MHK devices with commensurate changes in the turbulent kinetic energy and its dissipation rate.

  3. Superplastic forming using NIKE3D

    SciTech Connect

    Puso, M.

    1996-12-04

    The superplastic forming process requires careful control of strain rates in order to avoid strain localizations. A load scheduler was developed and implemented into the nonlinear finite element code NIKE3D to provide strain rate control during forming simulation and process schedule output. Often the sheets being formed in SPF are very thin such that less expensive membrane elements can be used as opposed to shell elements. A large strain membrane element was implemented into NIKE3D to assist in SPF process modeling.

  4. Development and Testing of EFIT 3D Equilibrium Reconstruction Capability

    NASA Astrophysics Data System (ADS)

    Lao, L. L.; Ferraro, N. M.; Strait, E. J.; Turnbull, A. D.; King, J. D.

    2014-10-01

    Recent development and testing of EFIT capability to reconstruct tokamak 3D perturbed equilibrium are described. The 3D extension is based on an expansion of the MHD equations to account for the 3D effects. EFIT uses the cylindrical coordinate system and can include magnetic island and stochastic effects. Several linearization schemes are being explored to improve the EFIT 3D perturbed solutions. Algorithms are also being developed to allow EFIT to reconstruct 3D perturbed equilibria directly making use of plasma response to 3D perturbations from the MARS or M3D-C1 MHD codes. Other efforts include testing of the new EFIT 3D capability using simulated magnetic data based on response calculations from MARS and M3D-C1, and performing detailed benchmarking calculations against other 3D codes such as VMEC/V3FIT. Reconstruction examples using EFIT and the new DIII-D 3D magnetic measurements to reconstruct 3D perturbed experimental equilibria using well-diagnosed discharges from DIII-D error field, RWM, and RMP experiments will be presented. Work supported by the US DOE under DE-FC02-04ER54698 and DE-FG02-95ER54309.

  5. 3D unstructured mesh discontinuous finite element hydro

    SciTech Connect

    Prasad, M.K.; Kershaw, D.S.; Shaw, M.J.

    1995-07-01

    The authors present detailed features of the ICF3D hydrodynamics code used for inertial fusion simulations. This code is intended to be a state-of-the-art upgrade of the well-known fluid code, LASNEX. ICF3D employs discontinuous finite elements on a discrete unstructured mesh consisting of a variety of 3D polyhedra including tetrahedra, prisms, and hexahedra. The authors discussed details of how the ROE-averaged second-order convection was applied on the discrete elements, and how the C++ coding interface has helped to simplify implementing the many physics and numerics modules within the code package. The author emphasized the virtues of object-oriented design in large scale projects such as ICF3D.

  6. Recent EFIT Developments and 3D Extension

    NASA Astrophysics Data System (ADS)

    Lao, L. L.; Chu, M. S.; St. John, H. E.; Strait, E. J.; Montgomery, A. L.; Perkins, F. W.

    2006-10-01

    Recent developments of the equilibrium reconstruction code EFIT and its 3D extension to model toroidally asymmetric effects due to error and externally applied perturbation magnetic fields are presented. These include a new more complete uncertainty matrix for magnetic diagnostics based on detailed knowledge about their fabrication, installation, calibration, and operation. A new algorithm to efficiently compute high bootstrap-fraction equilibria that explicitly separates out the Pfirsch-Schluter and bootstrap contributions to the poloidal current stream function is also being developed. Other on-going and planned developments include a new computational structure based on Fortran 90/95 with a unified interface that can conveniently accommodate different tokamak devices and grid sizes, as well as a computational link that allows easy integration with transport and stability physics modules for integrated modeling. EFIT reconstruction capability is also being extended to 3D based on perturbation solutions to the 3D Grad-Shafranov equilibrium equation.

  7. 3D differential phase contrast microscopy

    NASA Astrophysics Data System (ADS)

    Chen, Michael; Tian, Lei; Waller, Laura

    2016-03-01

    We demonstrate three-dimensional (3D) optical phase and amplitude reconstruction based on coded source illumination using a programmable LED array. Multiple stacks of images along the optical axis are computed from recorded intensities captured by multiple images under off-axis illumination. Based on the first Born approximation, a linear differential phase contrast (DPC) model is built between 3D complex index of refraction and the intensity stacks. Therefore, 3D volume reconstruction can be achieved via a fast inversion method, without the intermediate 2D phase retrieval step. Our system employs spatially partially coherent illumination, so the transverse resolution achieves twice the NA of coherent systems, while axial resolution is also improved 2× as compared to holographic imaging.

  8. 3-D Mesh Generation Nonlinear Systems

    SciTech Connect

    Christon, M. A.; Dovey, D.; Stillman, D. W.; Hallquist, J. O.; Rainsberger, R. B

    1994-04-07

    INGRID is a general-purpose, three-dimensional mesh generator developed for use with finite element, nonlinear, structural dynamics codes. INGRID generates the large and complex input data files for DYNA3D, NIKE3D, FACET, and TOPAZ3D. One of the greatest advantages of INGRID is that virtually any shape can be described without resorting to wedge elements, tetrahedrons, triangular elements or highly distorted quadrilateral or hexahedral elements. Other capabilities available are in the areas of geometry and graphics. Exact surface equations and surface intersections considerably improve the ability to deal with accurate models, and a hidden line graphics algorithm is included which is efficient on the most complicated meshes. The primary new capability is associated with the boundary conditions, loads, and material properties required by nonlinear mechanics programs. Commands have been designed for each case to minimize user effort. This is particularly important since special processing is almost always required for each load or boundary condition.

  9. Scoops3D: software to analyze 3D slope stability throughout a digital landscape

    USGS Publications Warehouse

    Reid, Mark E.; Christian, Sarah B.; Brien, Dianne L.; Henderson, Scott T.

    2015-01-01

    install the compiled Scoops3D program, the GUI (Scoops3D-i), and associated documentation. Several Scoops3D examples, including all input and output files, are available as well. The source code is written in the Fortran 90 language and can be compiled to run on any computer operating system with an appropriate compiler.

  10. Planetary Torque in 3D Isentropic Disks

    NASA Astrophysics Data System (ADS)

    Fung, Jeffrey; Masset, Frédéric; Lega, Elena; Velasco, David

    2017-03-01

    Planetary migration is inherently a three-dimensional (3D) problem, because Earth-size planetary cores are deeply embedded in protoplanetary disks. Simulations of these 3D disks remain challenging due to the steep resolution requirements. Using two different hydrodynamics codes, FARGO3D and PEnGUIn, we simulate disk–planet interaction for a one to five Earth-mass planet embedded in an isentropic disk. We measure the torque on the planet and ensure that the measurements are converged both in resolution and between the two codes. We find that the torque is independent of the smoothing length of the planet’s potential (r s), and that it has a weak dependence on the adiabatic index of the gaseous disk (γ). The torque values correspond to an inward migration rate qualitatively similar to previous linear calculations. We perform additional simulations with explicit radiative transfer using FARGOCA, and again find agreement between 3D simulations and existing torque formulae. We also present the flow pattern around the planets that show active flow is present within the planet’s Hill sphere, and meridional vortices are shed downstream. The vertical flow speed near the planet is faster for a smaller r s or γ, up to supersonic speeds for the smallest r s and γ in our study.

  11. HPF Implementation of ARC3D

    NASA Technical Reports Server (NTRS)

    Frumkin, Michael; Yan, Jerry

    1999-01-01

    We present an HPF (High Performance Fortran) implementation of ARC3D code along with the profiling and performance data on SGI Origin 2000. Advantages and limitations of HPF as a parallel programming language for CFD applications are discussed. For achieving good performance results we used the data distributions optimized for implementation of implicit and explicit operators of the solver and boundary conditions. We compare the results with MPI and directive based implementations.

  12. 3D Vectorial Time Domain Computational Integrated Photonics

    SciTech Connect

    Kallman, J S; Bond, T C; Koning, J M; Stowell, M L

    2007-02-16

    The design of integrated photonic structures poses considerable challenges. 3D-Time-Domain design tools are fundamental in enabling technologies such as all-optical logic, photonic bandgap sensors, THz imaging, and fast radiation diagnostics. Such technologies are essential to LLNL and WFO sponsors for a broad range of applications: encryption for communications and surveillance sensors (NSA, NAI and IDIV/PAT); high density optical interconnects for high-performance computing (ASCI); high-bandwidth instrumentation for NIF diagnostics; micro-sensor development for weapon miniaturization within the Stockpile Stewardship and DNT programs; and applications within HSO for CBNP detection devices. While there exist a number of photonics simulation tools on the market, they primarily model devices of interest to the communications industry. We saw the need to extend our previous software to match the Laboratory's unique emerging needs. These include modeling novel material effects (such as those of radiation induced carrier concentrations on refractive index) and device configurations (RadTracker bulk optics with radiation induced details, Optical Logic edge emitting lasers with lateral optical inputs). In addition we foresaw significant advantages to expanding our own internal simulation codes: parallel supercomputing could be incorporated from the start, and the simulation source code would be accessible for modification and extension. This work addressed Engineering's Simulation Technology Focus Area, specifically photonics. Problems addressed from the Engineering roadmap of the time included modeling the Auston switch (an important THz source/receiver), modeling Vertical Cavity Surface Emitting Lasers (VCSELs, which had been envisioned as part of fast radiation sensors), and multi-scale modeling of optical systems (for a variety of applications). We proposed to develop novel techniques to numerically solve the 3D multi-scale propagation problem for both the microchip

  13. Numerical study of the 3-D effect on FEL performance and its application to the APS LEUTL FEL

    SciTech Connect

    Chae, Y.C.

    1998-09-01

    A Low-Energy Undulator Test Line (LEUTL) is under construction at the Advanced Photon Source (APS). In LEUTL periodic focusing is provided by external quadrupoles. This results in an elliptical beam with its betatron oscillation envelope varying along the undulators. The free-electron laser (FEL) interaction with such a beam will exhibit truly 3-D effects. Thus the investigation of 3-D effects is important in optimizing the FEL performance. The programs GINGER and TDA3D, coupled with theoretically known facts, have been used for this purpose. Both programs are fully 3-D in moving the particle, but model the interaction between particles and axially symmetric electromagnetic waves. Even though TDA3D can include a few azimuthal modes in the interaction, it is still not a fully 3-D FEL code. However, they show that these 2-D programs can still be used for an elliptical beam whose aspect ratio is within certain limits. The author presents numerical results of FEL performance for the circular beam, the elliptical beam, and finally for the beam in the realistic LEUTL lattice.

  14. 3D Equilibrium Reconstructions in DIII-D

    NASA Astrophysics Data System (ADS)

    Lao, L. L.; Ferraro, N. W.; Strait, E. J.; Turnbull, A. D.; King, J. D.; Hirshman, H. P.; Lazarus, E. A.; Sontag, A. C.; Hanson, J.; Trevisan, G.

    2013-10-01

    Accurate and efficient 3D equilibrium reconstruction is needed in tokamaks for study of 3D magnetic field effects on experimentally reconstructed equilibrium and for analysis of MHD stability experiments with externally imposed magnetic perturbations. A large number of new magnetic probes have been recently installed in DIII-D to improve 3D equilibrium measurements and to facilitate 3D reconstructions. The V3FIT code has been in use in DIII-D to support 3D reconstruction and the new magnetic diagnostic design. V3FIT is based on the 3D equilibrium code VMEC that assumes nested magnetic surfaces. V3FIT uses a pseudo-Newton least-square algorithm to search for the solution vector. In parallel, the EFIT equilibrium reconstruction code is being extended to allow for 3D effects using a perturbation approach based on an expansion of the MHD equations. EFIT uses the cylindrical coordinate system and can include the magnetic island and stochastic effects. Algorithms are being developed to allow EFIT to reconstruct 3D perturbed equilibria directly making use of plasma response to 3D perturbations from the GATO, MARS-F, or M3D-C1 MHD codes. DIII-D 3D reconstruction examples using EFIT and V3FIT and the new 3D magnetic data will be presented. Work supported in part by US DOE under DE-FC02-04ER54698, DE-FG02-95ER54309 and DE-AC05-06OR23100.

  15. Superplot3d: an open source GUI tool for 3d trajectory visualisation and elementary processing.

    PubMed

    Whitehorn, Luke J; Hawkes, Frances M; Dublon, Ian An

    2013-09-30

    When acquiring simple three-dimensional (3d) trajectory data it is common to accumulate large coordinate data sets. In order to examine integrity and consistency of object tracking, it is often necessary to rapidly visualise these data. Ordinarily, to achieve this the user must either execute 3d plotting functions in a numerical computing environment or manually inspect data in two dimensions, plotting each individual axis.Superplot3d is an open source MATLAB script which takes tab delineated Cartesian data points in the form x, y, z and time and generates an instant visualization of the object's trajectory in free-rotational three dimensions. Whole trajectories may be instantly presented, allowing for rapid inspection. Executable from the MATLAB command line (or deployable as a compiled standalone application) superplot3d also provides simple GUI controls to obtain rudimentary trajectory information, allow specific visualization of trajectory sections and perform elementary processing.Superplot3d thus provides a framework for non-programmers and programmers alike, to recreate recently acquired 3d object trajectories in rotatable 3d space. It is intended, via the use of a preference driven menu to be flexible and work with output from multiple tracking software systems. Source code and accompanying GUIDE .fig files are provided for deployment and further development.

  16. 3D Spectroscopy in Astronomy

    NASA Astrophysics Data System (ADS)

    Mediavilla, Evencio; Arribas, Santiago; Roth, Martin; Cepa-Nogué, Jordi; Sánchez, Francisco

    2011-09-01

    Preface; Acknowledgements; 1. Introductory review and technical approaches Martin M. Roth; 2. Observational procedures and data reduction James E. H. Turner; 3. 3D Spectroscopy instrumentation M. A. Bershady; 4. Analysis of 3D data Pierre Ferruit; 5. Science motivation for IFS and galactic studies F. Eisenhauer; 6. Extragalactic studies and future IFS science Luis Colina; 7. Tutorials: how to handle 3D spectroscopy data Sebastian F. Sánchez, Begona García-Lorenzo and Arlette Pécontal-Rousset.

  17. 3D Elevation Program—Virtual USA in 3D

    USGS Publications Warehouse

    Lukas, Vicki; Stoker, J.M.

    2016-04-14

    The U.S. Geological Survey (USGS) 3D Elevation Program (3DEP) uses a laser system called ‘lidar’ (light detection and ranging) to create a virtual reality map of the Nation that is very accurate. 3D maps have many uses with new uses being discovered all the time.  

  18. CFL3D: Its History and Some Recent Applications

    NASA Technical Reports Server (NTRS)

    Rumsey, C. L.; Biedron, R. T.; Thomas, J. L.

    1997-01-01

    The history of the Computational Fluids Laboratory -3D (CFL3D) Navier-Stokes computer code is discussed and a comprehensive reference list is given. Three recent advanced applications are presented (1) Wing with partial-spanflap, (2) F/A-18 with forebody control strake, and (3) Noise predictions for an advanced ducted propeller turbomachinery flow.

  19. Visualization of 3D Geological Data using COLLADA and KML

    NASA Astrophysics Data System (ADS)

    Choi, Yosoon; Um, Jeong-Gi; Park, Myong-Ho

    2013-04-01

    This study presents a method to visualize 3D geological data using COLLAborative Design Activity(COLLADA, an open standard XML schema for establishing interactive 3D applications) and Keyhole Markup Language(KML, the XML-based scripting language of Google Earth).We used COLLADA files to represent different 3D geological data such as borehole, fence section, surface-based 3D volume and 3D grid by triangle meshes(a set of triangles connected by their common edges or corners). The COLLADA files were imported into the 3D render window of Google Earth using KML codes. An application to the Grosmont formation in Alberta, Canada showed that the combination of COLLADA and KML enables Google Earth to visualize 3D geological structures and properties.

  20. MAP3D: a media processor approach for high-end 3D graphics

    NASA Astrophysics Data System (ADS)

    Darsa, Lucia; Stadnicki, Steven; Basoglu, Chris

    1999-12-01

    Equator Technologies, Inc. has used a software-first approach to produce several programmable and advanced VLIW processor architectures that have the flexibility to run both traditional systems tasks and an array of media-rich applications. For example, Equator's MAP1000A is the world's fastest single-chip programmable signal and image processor targeted for digital consumer and office automation markets. The Equator MAP3D is a proposal for the architecture of the next generation of the Equator MAP family. The MAP3D is designed to achieve high-end 3D performance and a variety of customizable special effects by combining special graphics features with high performance floating-point and media processor architecture. As a programmable media processor, it offers the advantages of a completely configurable 3D pipeline--allowing developers to experiment with different algorithms and to tailor their pipeline to achieve the highest performance for a particular application. With the support of Equator's advanced C compiler and toolkit, MAP3D programs can be written in a high-level language. This allows the compiler to successfully find and exploit any parallelism in a programmer's code, thus decreasing the time to market of a given applications. The ability to run an operating system makes it possible to run concurrent applications in the MAP3D chip, such as video decoding while executing the 3D pipelines, so that integration of applications is easily achieved--using real-time decoded imagery for texturing 3D objects, for instance. This novel architecture enables an affordable, integrated solution for high performance 3D graphics.

  1. 3D World Building System

    ScienceCinema

    None

    2016-07-12

    This video provides an overview of the Sandia National Laboratories developed 3-D World Model Building capability that provides users with an immersive, texture rich 3-D model of their environment in minutes using a laptop and color and depth camera.

  2. 3D Buckligami: Digital Matter

    NASA Astrophysics Data System (ADS)

    van Hecke, Martin; de Reus, Koen; Florijn, Bastiaan; Coulais, Corentin

    2014-03-01

    We present a class of elastic structures which exhibit collective buckling in 3D, and create these by a 3D printing/moulding technique. Our structures consist of cubic lattice of anisotropic unit cells, and we show that their mechanical properties are programmable via the orientation of these unit cells.

  3. 3D World Building System

    SciTech Connect

    2013-10-30

    This video provides an overview of the Sandia National Laboratories developed 3-D World Model Building capability that provides users with an immersive, texture rich 3-D model of their environment in minutes using a laptop and color and depth camera.

  4. Market study: 3-D eyetracker

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A market study of a proposed version of a 3-D eyetracker for initial use at NASA's Ames Research Center was made. The commercialization potential of a simplified, less expensive 3-D eyetracker was ascertained. Primary focus on present and potential users of eyetrackers, as well as present and potential manufacturers has provided an effective means of analyzing the prospects for commercialization.

  5. ICER-3D Hyperspectral Image Compression Software

    NASA Technical Reports Server (NTRS)

    Xie, Hua; Kiely, Aaron; Klimesh, matthew; Aranki, Nazeeh

    2010-01-01

    Software has been developed to implement the ICER-3D algorithm. ICER-3D effects progressive, three-dimensional (3D), wavelet-based compression of hyperspectral images. If a compressed data stream is truncated, the progressive nature of the algorithm enables reconstruction of hyperspectral data at fidelity commensurate with the given data volume. The ICER-3D software is capable of providing either lossless or lossy compression, and incorporates an error-containment scheme to limit the effects of data loss during transmission. The compression algorithm, which was derived from the ICER image compression algorithm, includes wavelet-transform, context-modeling, and entropy coding subalgorithms. The 3D wavelet decomposition structure used by ICER-3D exploits correlations in all three dimensions of sets of hyperspectral image data, while facilitating elimination of spectral ringing artifacts, using a technique summarized in "Improving 3D Wavelet-Based Compression of Spectral Images" (NPO-41381), NASA Tech Briefs, Vol. 33, No. 3 (March 2009), page 7a. Correlation is further exploited by a context-modeling subalgorithm, which exploits spectral dependencies in the wavelet-transformed hyperspectral data, using an algorithm that is summarized in "Context Modeler for Wavelet Compression of Hyperspectral Images" (NPO-43239), which follows this article. An important feature of ICER-3D is a scheme for limiting the adverse effects of loss of data during transmission. In this scheme, as in the similar scheme used by ICER, the spatial-frequency domain is partitioned into rectangular error-containment regions. In ICER-3D, the partitions extend through all the wavelength bands. The data in each partition are compressed independently of those in the other partitions, so that loss or corruption of data from any partition does not affect the other partitions. Furthermore, because compression is progressive within each partition, when data are lost, any data from that partition received

  6. Euro3D Science Conference

    NASA Astrophysics Data System (ADS)

    Walsh, J. R.

    2004-02-01

    The Euro3D RTN is an EU funded Research Training Network to foster the exploitation of 3D spectroscopy in Europe. 3D spectroscopy is a general term for spectroscopy of an area of the sky and derives its name from its two spatial + one spectral dimensions. There are an increasing number of instruments which use integral field devices to achieve spectroscopy of an area of the sky, either using lens arrays, optical fibres or image slicers, to pack spectra of multiple pixels on the sky (``spaxels'') onto a 2D detector. On account of the large volume of data and the special methods required to reduce and analyse 3D data, there are only a few centres of expertise and these are mostly involved with instrument developments. There is a perceived lack of expertise in 3D spectroscopy spread though the astronomical community and its use in the armoury of the observational astronomer is viewed as being highly specialised. For precisely this reason the Euro3D RTN was proposed to train young researchers in this area and develop user tools to widen the experience with this particular type of data in Europe. The Euro3D RTN is coordinated by Martin M. Roth (Astrophysikalisches Institut Potsdam) and has been running since July 2002. The first Euro3D science conference was held in Cambridge, UK from 22 to 23 May 2003. The main emphasis of the conference was, in keeping with the RTN, to expose the work of the young post-docs who are funded by the RTN. In addition the team members from the eleven European institutes involved in Euro3D also presented instrumental and observational developments. The conference was organized by Andy Bunker and held at the Institute of Astronomy. There were over thirty participants and 26 talks covered the whole range of application of 3D techniques. The science ranged from Galactic planetary nebulae and globular clusters to kinematics of nearby galaxies out to objects at high redshift. Several talks were devoted to reporting recent observations with newly

  7. 3D vision system assessment

    NASA Astrophysics Data System (ADS)

    Pezzaniti, J. Larry; Edmondson, Richard; Vaden, Justin; Hyatt, Bryan; Chenault, David B.; Kingston, David; Geulen, Vanilynmae; Newell, Scott; Pettijohn, Brad

    2009-02-01

    In this paper, we report on the development of a 3D vision system consisting of a flat panel stereoscopic display and auto-converging stereo camera and an assessment of the system's use for robotic driving, manipulation, and surveillance operations. The 3D vision system was integrated onto a Talon Robot and Operator Control Unit (OCU) such that direct comparisons of the performance of a number of test subjects using 2D and 3D vision systems were possible. A number of representative scenarios were developed to determine which tasks benefited most from the added depth perception and to understand when the 3D vision system hindered understanding of the scene. Two tests were conducted at Fort Leonard Wood, MO with noncommissioned officers ranked Staff Sergeant and Sergeant First Class. The scenarios; the test planning, approach and protocols; the data analysis; and the resulting performance assessment of the 3D vision system are reported.

  8. 3D printing in dentistry.

    PubMed

    Dawood, A; Marti Marti, B; Sauret-Jackson, V; Darwood, A

    2015-12-01

    3D printing has been hailed as a disruptive technology which will change manufacturing. Used in aerospace, defence, art and design, 3D printing is becoming a subject of great interest in surgery. The technology has a particular resonance with dentistry, and with advances in 3D imaging and modelling technologies such as cone beam computed tomography and intraoral scanning, and with the relatively long history of the use of CAD CAM technologies in dentistry, it will become of increasing importance. Uses of 3D printing include the production of drill guides for dental implants, the production of physical models for prosthodontics, orthodontics and surgery, the manufacture of dental, craniomaxillofacial and orthopaedic implants, and the fabrication of copings and frameworks for implant and dental restorations. This paper reviews the types of 3D printing technologies available and their various applications in dentistry and in maxillofacial surgery.

  9. PLOT3D user's manual

    NASA Technical Reports Server (NTRS)

    Walatka, Pamela P.; Buning, Pieter G.; Pierce, Larry; Elson, Patricia A.

    1990-01-01

    PLOT3D is a computer graphics program designed to visualize the grids and solutions of computational fluid dynamics. Seventy-four functions are available. Versions are available for many systems. PLOT3D can handle multiple grids with a million or more grid points, and can produce varieties of model renderings, such as wireframe or flat shaded. Output from PLOT3D can be used in animation programs. The first part of this manual is a tutorial that takes the reader, keystroke by keystroke, through a PLOT3D session. The second part of the manual contains reference chapters, including the helpfile, data file formats, advice on changing PLOT3D, and sample command files.

  10. 2-D and 3-D Visualization of the Freshwater/Saltwater Mixing Front, and Zones of Preferential Groundwater Flow in the Karst Biscayne Coastal Aquifer using Electromagnetic Induction Techniques, Miami, Southeastern Florida.

    NASA Astrophysics Data System (ADS)

    Stalker, J. C.; Glaccum, R.

    2005-05-01

    The Biscayne aquifer is unconfined, composed primarily of Karst limestone, and underlies all of Miami-Dade County and much of Biscayne Bay in southeastern Florida. It is the sole source of drinking water for the 3 million inhabitants of the city of Miami and Miami-Dade County, as well as portions of Broward and Monroe Counties. Saltwater intrusion is a prominent problem for all coastal aquifers including the Biscayne aquifer. Simple and quick detection of the three-dimensional saltwater/freshwater interface has been problematic without the use of extensive sounding surveys or multiple well sampling. We are developing a technique combining rapid EM-31 surface surveys with EM-31 vertical soundings to model the depth to the saltwater/freshwater front at two sites located within a half mile of Biscayne Bay. The EM-31 has a maximum signal penetration of about 25ft allowing for accurate near shore surveys. Depths to the saltwater have ranged from over 25 ft inland to less than 2-3 ft near the Bay and saltwater mangroves. Changes in conductivity along survey lines of equal elevation that are equidistant from the Bay may indicate zones of preferential flow due to conduit networks or the presence of backfill, both of which exacerbate saltwater intrusion. All surveys show a rapid change from fresh to brackish water as you move toward the Bay indicating a shallow and abrupt mixing zone. Using a simple depth-modeling program, a wire frame contour map of the mixing zone can be constructed. This technique has proven to be a quick, inexpensive method for first-order hydrogeological and spatial analysis of the saltwater/freshwater interface. In an allied study we are using down-hole electromagnetic induction techniques with an EM-39 tool on existing wells, analyzing fluctuations in conductivity within the saltwater zone to look for zones of high permeability in the aquifer. Conductivity fluctuates within the mixing zone from brackish values to values equivalent to Biscayne Bay

  11. 3D-spectral CDIs: a fast alternative to 3D inversion?

    NASA Astrophysics Data System (ADS)

    Macnae, James

    2015-09-01

    Virtually all airborne electromagnetic (AEM) data is interpreted using stitched 1D conductivity sections, derived from constrained inversion or fast but fairly accurate approximations. A small subset of this AEM data recently has been inverted using either block 3D models or thin plates, which processes have limitations in terms of cost and accuracy, and the results are in general strongly biased by the choice of starting models. Recent developments in spectral modelling have allowed fast 3D approximations of the EM response of both vortex induction and current gathering for simple geological target geometries. Fitting these spectral responses to AEM data should be sufficient to accurately locate current systems within the ground, and the behaviour of these local current systems can in theory approximately define a conductivity structure in 3D. This paper describes the results of initial testing of the algorithm in fitting vortex induction in a small target at the Forrestania test range, Western Australia, using results from a versatile time-domain electromagnetic (VTEM)-Max survey.

  12. Every Day a New 3D Printing Material

    ERIC Educational Resources Information Center

    Hughes, Bill; Mona, Lynn; Wilson, Greg; Seamans, Jeff; McAninch, Steve; Stout, Heath

    2017-01-01

    A handful of technological episodes: fire, wheel and axle, Industrial Revolution, Faraday's discovery of electromagnetic induction, the transistor, and the digital age, have historically altered humanity. We are now witnessing/participating in the next transformational technology: 3D printing. Although dating back nearly 30 years, the technology…

  13. PLOT3D/AMES, APOLLO UNIX VERSION USING GMR3D (WITHOUT TURB3D)

    NASA Technical Reports Server (NTRS)

    Buning, P.

    1994-01-01

    PLOT3D is an interactive graphics program designed to help scientists visualize computational fluid dynamics (CFD) grids and solutions. Today, supercomputers and CFD algorithms can provide scientists with simulations of such highly complex phenomena that obtaining an understanding of the simulations has become a major problem. Tools which help the scientist visualize the simulations can be of tremendous aid. PLOT3D/AMES offers more functions and features, and has been adapted for more types of computers than any other CFD graphics program. Version 3.6b+ is supported for five computers and graphic libraries. Using PLOT3D, CFD physicists can view their computational models from any angle, observing the physics of problems and the quality of solutions. As an aid in designing aircraft, for example, PLOT3D's interactive computer graphics can show vortices, temperature, reverse flow, pressure, and dozens of other characteristics of air flow during flight. As critical areas become obvious, they can easily be studied more closely using a finer grid. PLOT3D is part of a computational fluid dynamics software cycle. First, a program such as 3DGRAPE (ARC-12620) helps the scientist generate computational grids to model an object and its surrounding space. Once the grids have been designed and parameters such as the angle of attack, Mach number, and Reynolds number have been specified, a "flow-solver" program such as INS3D (ARC-11794 or COS-10019) solves the system of equations governing fluid flow, usually on a supercomputer. Grids sometimes have as many as two million points, and the "flow-solver" produces a solution file which contains density, x- y- and z-momentum, and stagnation energy for each grid point. With such a solution file and a grid file containing up to 50 grids as input, PLOT3D can calculate and graphically display any one of 74 functions, including shock waves, surface pressure, velocity vectors, and particle traces. PLOT3D's 74 functions are organized into

  14. PLOT3D/AMES, APOLLO UNIX VERSION USING GMR3D (WITH TURB3D)

    NASA Technical Reports Server (NTRS)

    Buning, P.

    1994-01-01

    PLOT3D is an interactive graphics program designed to help scientists visualize computational fluid dynamics (CFD) grids and solutions. Today, supercomputers and CFD algorithms can provide scientists with simulations of such highly complex phenomena that obtaining an understanding of the simulations has become a major problem. Tools which help the scientist visualize the simulations can be of tremendous aid. PLOT3D/AMES offers more functions and features, and has been adapted for more types of computers than any other CFD graphics program. Version 3.6b+ is supported for five computers and graphic libraries. Using PLOT3D, CFD physicists can view their computational models from any angle, observing the physics of problems and the quality of solutions. As an aid in designing aircraft, for example, PLOT3D's interactive computer graphics can show vortices, temperature, reverse flow, pressure, and dozens of other characteristics of air flow during flight. As critical areas become obvious, they can easily be studied more closely using a finer grid. PLOT3D is part of a computational fluid dynamics software cycle. First, a program such as 3DGRAPE (ARC-12620) helps the scientist generate computational grids to model an object and its surrounding space. Once the grids have been designed and parameters such as the angle of attack, Mach number, and Reynolds number have been specified, a "flow-solver" program such as INS3D (ARC-11794 or COS-10019) solves the system of equations governing fluid flow, usually on a supercomputer. Grids sometimes have as many as two million points, and the "flow-solver" produces a solution file which contains density, x- y- and z-momentum, and stagnation energy for each grid point. With such a solution file and a grid file containing up to 50 grids as input, PLOT3D can calculate and graphically display any one of 74 functions, including shock waves, surface pressure, velocity vectors, and particle traces. PLOT3D's 74 functions are organized into

  15. M3D project for simulation studies of plasmas

    SciTech Connect

    Park, W.; Belova, E.V.; Fu, G.Y.; Strauss, H.R.; Sugiyama, L.E.

    1998-12-31

    The M3D (Multi-level 3D) project carries out simulation studies of plasmas of various regimes using multi-levels of physics, geometry, and mesh schemes in one code package. This paper and papers by Strauss, Sugiyama, and Belova in this workshop describe the project, and present examples of current applications. The currently available physics models of the M3D project are MHD, two-fluids, gyrokinetic hot particle/MHD hybrid, and gyrokinetic particle ion/two-fluid hybrid models. The code can be run with both structured and unstructured meshes.

  16. GEN3D Ver. 1.37

    SciTech Connect

    2012-01-04

    GEN3D is a three-dimensional mesh generation program. The three-dimensional mesh is generated by mapping a two-dimensional mesh into threedimensions according to one of four types of transformations: translating, rotating, mapping onto a spherical surface, and mapping onto a cylindrical surface. The generated three-dimensional mesh can then be reoriented by offsetting, reflecting about an axis, and revolving about an axis. GEN3D can be used to mesh geometries that are axisymmetric or planar, but, due to three-dimensional loading or boundary conditions, require a three-dimensional finite element mesh and analysis. More importantly, it can be used to mesh complex three-dimensional geometries composed of several sections when the sections can be defined in terms of transformations of two dimensional geometries. The code GJOIN is then used to join the separate sections into a single body. GEN3D reads and writes twodimensional and threedimensional mesh databases in the GENESIS database format; therefore, it is compatible with the preprocessing, postprocessing, and analysis codes used by the Engineering Analysis Department at Sandia National Laboratories, Albuquerque, NM.

  17. A 3-d modular gripper design tool

    SciTech Connect

    Brown, R.G.; Brost, R.C.

    1997-02-01

    Modular fixturing kits are sets of components used for flexible, rapid construction of fixtures. A modular vise is a parallel-jaw vise, each jaw of which is a modular fixture plate with a regular grid of precisely positioned holes. To fixture a part, one places pins in some of the holes so that when the vise is closed, the part is reliably located and completely constrained. The modular vise concept can be adapted easily to the design of modular parallel-jaw grippers for robots. By attaching a grid-plate to each jaw of a parallel-jaw gripper, one gains the ability to easily construct high-quality grasps for a wide variety of parts from a standard set of hardware. Wallack and Canny developed an algorithm for planning planar grasp configurations for the modular vise. In this paper, the authors expand this work to produce a 3-d fixture/gripper design tool. They describe several analyses they have added to the planar algorithm, including a 3-d grasp quality metric based on force information, 3-d geometric loading analysis, and inter-gripper interference analysis. Finally, the authors describe two applications of their code. One of these is an internal application at Sandia, while the other shows a potential use of the code for designing part of an agile assembly line.

  18. Computational modeling of RNA 3D structures and interactions.

    PubMed

    Dawson, Wayne K; Bujnicki, Janusz M

    2016-04-01

    RNA molecules have key functions in cellular processes beyond being carriers of protein-coding information. These functions are often dependent on the ability to form complex three-dimensional (3D) structures. However, experimental determination of RNA 3D structures is difficult, which has prompted the development of computational methods for structure prediction from sequence. Recent progress in 3D structure modeling of RNA and emerging approaches for predicting RNA interactions with ions, ligands and proteins have been stimulated by successes in protein 3D structure modeling.

  19. The EISCAT_3D Science Case

    NASA Astrophysics Data System (ADS)

    Tjulin, A.; Mann, I.; McCrea, I.; Aikio, A. T.

    2013-05-01

    EISCAT_3D will be a world-leading international research infrastructure using the incoherent scatter technique to study the atmosphere in the Fenno-Scandinavian Arctic and to investigate how the Earth's atmosphere is coupled to space. The EISCAT_3D phased-array multistatic radar system will be operated by EISCAT Scientific Association and thus be an integral part of an organisation that has successfully been running incoherent scatter radars for more than thirty years. The baseline design of the radar system contains a core site with transmitting and receiving capabilities located close to the intersection of the Swedish, Norwegian and Finnish borders and five receiving sites located within 50 to 250 km from the core. The EISCAT_3D project is currently in its Preparatory Phase and can smoothly transit into implementation in 2014, provided sufficient funding. Construction can start 2016 and first operations in 2018. The EISCAT_3D Science Case is prepared as part of the Preparatory Phase. It is regularly updated with annual new releases, and it aims at being a common document for the whole future EISCAT_3D user community. The areas covered by the Science Case are atmospheric physics and global change; space and plasma physics; solar system research; space weather and service applications; and radar techniques, new methods for coding and analysis. Two of the aims for EISCAT_3D are to understand the ways natural variability in the upper atmosphere, imposed by the Sun-Earth system, can influence the middle and lower atmosphere, and to improve the predictivity of atmospheric models by providing higher resolution observations to replace the current parametrised input. Observations by EISCAT_3D will also be used to monitor the direct effects from the Sun on the ionosphere-atmosphere system and those caused by solar wind magnetosphere-ionosphere interaction. In addition, EISCAT_3D will be used for remote sensing the large-scale behaviour of the magnetosphere from its

  20. Unassisted 3D camera calibration

    NASA Astrophysics Data System (ADS)

    Atanassov, Kalin; Ramachandra, Vikas; Nash, James; Goma, Sergio R.

    2012-03-01

    With the rapid growth of 3D technology, 3D image capture has become a critical part of the 3D feature set on mobile phones. 3D image quality is affected by the scene geometry as well as on-the-device processing. An automatic 3D system usually assumes known camera poses accomplished by factory calibration using a special chart. In real life settings, pose parameters estimated by factory calibration can be negatively impacted by movements of the lens barrel due to shaking, focusing, or camera drop. If any of these factors displaces the optical axes of either or both cameras, vertical disparity might exceed the maximum tolerable margin and the 3D user may experience eye strain or headaches. To make 3D capture more practical, one needs to consider unassisted (on arbitrary scenes) calibration. In this paper, we propose an algorithm that relies on detection and matching of keypoints between left and right images. Frames containing erroneous matches, along with frames with insufficiently rich keypoint constellations, are detected and discarded. Roll, pitch yaw , and scale differences between left and right frames are then estimated. The algorithm performance is evaluated in terms of the remaining vertical disparity as compared to the maximum tolerable vertical disparity.

  1. 3D Scan Systems Integration

    DTIC Science & Technology

    2007-11-02

    AGENCY USE ONLY (Leave Blank) 2. REPORT DATE 5 Feb 98 4. TITLE AND SUBTITLE 3D Scan Systems Integration REPORT TYPE AND DATES COVERED...2-89) Prescribed by ANSI Std. Z39-1 298-102 [ EDO QUALITY W3PECTEDI DLA-ARN Final Report for US Defense Logistics Agency on DDFG-T2/P3: 3D...SCAN SYSTEMS INTEGRATION Contract Number SPO100-95-D-1014 Contractor Ohio University Delivery Order # 0001 Delivery Order Title 3D Scan Systems

  2. EFIT 3D Reconstruction and Recent Developments

    NASA Astrophysics Data System (ADS)

    Lao, L. L.; Chu, M. S.; St. John, H. E.; Strait, E. J.; Turnbull, A. D.; Ren, Q.; Jeon, Y. M.; Flannagan, D.

    2007-11-01

    Recent 3D extension of the EFIT equilibrium reconstruction code to model toroidally asymmetric effects due to error and externally applied perturbation magnetic fields and other developments are presented. The 3D extension is based on an expansion of the MHD equations. Other developments include a new computational structure based on Fortran 90/95 with a unified interface that can conveniently accommodate different tokamak devices and grid sizes, as well as a Python-based GUI. New computational links that allow easy integration with transport and stability physics modules to facilitate kinetic reconstruction and stability analysis are also being developed. A new more complete uncertainty matrix for magnetic diagnostics based on knowledge about their fabrication, installation, calibration, and operation has also been implemented into EFIT and tested. Reconstructions with the new magnetic uncertainty matrix yield results similar to those using the existing one but with more realistic fitting merit figures.

  3. Low Complexity Mode Decision for 3D-HEVC

    PubMed Central

    Li, Nana; Gan, Yong

    2014-01-01

    High efficiency video coding- (HEVC-) based 3D video coding (3D-HEVC) developed by joint collaborative team on 3D video coding (JCT-3V) for multiview video and depth map is an extension of HEVC standard. In the test model of 3D-HEVC, variable coding unit (CU) size decision and disparity estimation (DE) are introduced to achieve the highest coding efficiency with the cost of very high computational complexity. In this paper, a fast mode decision algorithm based on variable size CU and DE is proposed to reduce 3D-HEVC computational complexity. The basic idea of the method is to utilize the correlations between depth map and motion activity in prediction mode where variable size CU and DE are needed, and only in these regions variable size CU and DE are enabled. Experimental results show that the proposed algorithm can save about 43% average computational complexity of 3D-HEVC while maintaining almost the same rate-distortion (RD) performance. PMID:25254237

  4. 3D polymer scaffold arrays.

    PubMed

    Simon, Carl G; Yang, Yanyin; Dorsey, Shauna M; Ramalingam, Murugan; Chatterjee, Kaushik

    2011-01-01

    We have developed a combinatorial platform for fabricating tissue scaffold arrays that can be used for screening cell-material interactions. Traditional research involves preparing samples one at a time for characterization and testing. Combinatorial and high-throughput (CHT) methods lower the cost of research by reducing the amount of time and material required for experiments by combining many samples into miniaturized specimens. In order to help accelerate biomaterials research, many new CHT methods have been developed for screening cell-material interactions where materials are presented to cells as a 2D film or surface. However, biomaterials are frequently used to fabricate 3D scaffolds, cells exist in vivo in a 3D environment and cells cultured in a 3D environment in vitro typically behave more physiologically than those cultured on a 2D surface. Thus, we have developed a platform for fabricating tissue scaffold libraries where biomaterials can be presented to cells in a 3D format.

  5. Autofocus for 3D imaging

    NASA Astrophysics Data System (ADS)

    Lee-Elkin, Forest

    2008-04-01

    Three dimensional (3D) autofocus remains a significant challenge for the development of practical 3D multipass radar imaging. The current 2D radar autofocus methods are not readily extendable across sensor passes. We propose a general framework that allows a class of data adaptive solutions for 3D auto-focus across passes with minimal constraints on the scene contents. The key enabling assumption is that portions of the scene are sparse in elevation which reduces the number of free variables and results in a system that is simultaneously solved for scatterer heights and autofocus parameters. The proposed method extends 2-pass interferometric synthetic aperture radar (IFSAR) methods to an arbitrary number of passes allowing the consideration of scattering from multiple height locations. A specific case from the proposed autofocus framework is solved and demonstrates autofocus and coherent multipass 3D estimation across the 8 passes of the "Gotcha Volumetric SAR Data Set" X-Band radar data.

  6. Combinatorial 3D Mechanical Metamaterials

    NASA Astrophysics Data System (ADS)

    Coulais, Corentin; Teomy, Eial; de Reus, Koen; Shokef, Yair; van Hecke, Martin

    2015-03-01

    We present a class of elastic structures which exhibit 3D-folding motion. Our structures consist of cubic lattices of anisotropic unit cells that can be tiled in a complex combinatorial fashion. We design and 3d-print this complex ordered mechanism, in which we combine elastic hinges and defects to tailor the mechanics of the material. Finally, we use this large design space to encode smart functionalities such as surface patterning and multistability.

  7. 3-D magnetic field calculations for wiggglers using MAGNUS-3D

    SciTech Connect

    Pissanetzky, S.; Tompkins, P.

    1988-01-01

    The recent but steady trend toward increased magnetic and geometric complexity in the design of wigglers and undulators, of which tapered wigglers, hybrid structures, laced electromagnetic wigglers, magnetic cladding, twisters and magic structures are examples, has caused a need for reliable 3-D computer models and a better understanding of the behavior of magnetic systems in three dimensions. The capabilities of the MAGNUS-3D Group of Programs are ideally suited to solve this class of problems and provide insight into 3-D effects. MAGNUS-3D can solve any problem of Magnetostatics involving permanent magnets, linear or nonlinear ferromagnetic materials and electric conductors of any shape in space. The magnetic properties of permanent magnets are described by the complete nonlinear demagnetization curve as provided by the manufacturer, or, at the user's choice, by a simpler approximation involving the coercive force, the residual induction and the direction of magnetization. The ferromagnetic materials are described by a magnetization table and an accurate interpolation relation. An internal library with properties of common industrial steels is available. The conductors are independent of the mesh and are described in terms of conductor elements from an internal library.

  8. 3-D Force-balanced Magnetospheric Configurations

    SciTech Connect

    Sorin Zaharia; C.Z. Cheng; K. Maezawa

    2003-02-10

    The knowledge of plasma pressure is essential for many physics applications in the magnetosphere, such as computing magnetospheric currents and deriving magnetosphere-ionosphere coupling. A thorough knowledge of the 3-D pressure distribution has however eluded the community, as most in-situ pressure observations are either in the ionosphere or the equatorial region of the magnetosphere. With the assumption of pressure isotropy there have been attempts to obtain the pressure at different locations by either (a) mapping observed data (e.g., in the ionosphere) along the field lines of an empirical magnetospheric field model or (b) computing a pressure profile in the equatorial plane (in 2-D) or along the Sun-Earth axis (in 1-D) that is in force balance with the magnetic stresses of an empirical model. However, the pressure distributions obtained through these methods are not in force balance with the empirical magnetic field at all locations. In order to find a global 3-D plasma pressure distribution in force balance with the magnetospheric magnetic field, we have developed the MAG-3D code, that solves the 3-D force balance equation J x B = (upside-down delta) P computationally. Our calculation is performed in a flux coordinate system in which the magnetic field is expressed in terms of Euler potentials as B = (upside-down delta) psi x (upside-down delta) alpha. The pressure distribution, P = P(psi,alpha), is prescribed in the equatorial plane and is based on satellite measurements. In addition, computational boundary conditions for y surfaces are imposed using empirical field models. Our results provide 3-D distributions of magnetic field and plasma pressure as well as parallel and transverse currents for both quiet-time and disturbed magnetospheric conditions.

  9. Crashdynamics with DYNA3D: Capabilities and research directions

    NASA Technical Reports Server (NTRS)

    Whirley, Robert G.; Engelmann, Bruce E.

    1993-01-01

    The application of the explicit nonlinear finite element analysis code DYNA3D to crashworthiness problems is discussed. Emphasized in the first part of this work are the most important capabilities of an explicit code for crashworthiness analyses. The areas with significant research promise for the computational simulation of crash events are then addressed.

  10. Enhancements to the opera-3d suite

    NASA Astrophysics Data System (ADS)

    Riley, Christopher P.

    1997-02-01

    The OPERA-3D suite of programs has been enhanced to include 2 additional 3 dimensional finite element based solvers, with complimentary features in the pre- and postprocessing. SOPRANO computes electromagnetic fields at high frequency including displacement current effects. It has 2 modules—a deterministic solution at a user defined frequency and an eigenvalue solution for modal analysis. It is suitable for designing microwave structures and cavities found in particle accelerators. SCALA computes electrostatic fields in the presence of space charge from charged particle beams. The user may define the emission characteristics of electrodes or plasma surfaces and compute the resultant space charge limited beams, including the presence of magnetic fields. Typical applications in particle accelerators are electron guns and ion sources. Other enhancements to the suite include additional capabilities in TOSCA and ELEKTRA, the static and dynamic solvers.

  11. Sodium 3D COncentration MApping (COMA 3D) using 23Na and proton MRI

    NASA Astrophysics Data System (ADS)

    Truong, Milton L.; Harrington, Michael G.; Schepkin, Victor D.; Chekmenev, Eduard Y.

    2014-10-01

    Functional changes of sodium 3D MRI signals were converted into millimolar concentration changes using an open-source fully automated MATLAB toolbox. These concentration changes are visualized via 3D sodium concentration maps, and they are overlaid over conventional 3D proton images to provide high-resolution co-registration for easy correlation of functional changes to anatomical regions. Nearly 5000/h concentration maps were generated on a personal computer (ca. 2012) using 21.1 T 3D sodium MRI brain images of live rats with spatial resolution of 0.8 × 0.8 × 0.8 mm3 and imaging matrices of 60 × 60 × 60. The produced concentration maps allowed for non-invasive quantitative measurement of in vivo sodium concentration in the normal rat brain as a functional response to migraine-like conditions. The presented work can also be applied to sodium-associated changes in migraine, cancer, and other metabolic abnormalities that can be sensed by molecular imaging. The MATLAB toolbox allows for automated image analysis of the 3D images acquired on the Bruker platform and can be extended to other imaging platforms. The resulting images are presented in a form of series of 2D slices in all three dimensions in native MATLAB and PDF formats. The following is provided: (a) MATLAB source code for image processing, (b) the detailed processing procedures, (c) description of the code and all sub-routines, (d) example data sets of initial and processed data. The toolbox can be downloaded at: http://www.vuiis.vanderbilt.edu/~truongm/COMA3D/.

  12. Sodium 3D COncentration MApping (COMA 3D) Using 23Na and Proton MRI

    PubMed Central

    Truong, Milton L.; Harrington, Michael G.; Schepkin, Victor D.; Chekmenev, Eduard Y.

    2014-01-01

    Functional changes of sodium 3D MRI signals were converted into millimolar concentration changes using an open-source fully automated MATLAB toolbox. These concentration changes are visualized via 3D sodium concentration maps, and they are overlaid over conventional 3D proton images to provide high-resolution co-registration for easy correlation of functional changes to anatomical regions. Nearly 5000/hour concentration maps were generated on a personal computer (ca. 2012) using 21.1 T 3D sodium MRI brain images of live rats with spatial resolution of 0.8×0.8×0.8 mm3 and imaging matrices of 60×60×60. The produced concentration maps allowed for non-invasive quantitative measurement of in vivo sodium concentration in the normal rat brain as a functional response to migraine-like conditions. The presented work can also be applied to sodium-associated changes in migraine, cancer, and other metabolic abnormalities that can be sensed by molecular imaging. The MATLAB toolbox allows for automated image analysis of the 3D images acquired on the Bruker platform and can be extended to other imaging platforms. The resulting images are presented in a form of series of 2D slices in all three dimensions in native MATLAB and PDF formats. The following is provided: (a) MATLAB source code for image processing, (b) the detailed processing procedures, (c) description of the code and all sub-routines, (d) example data sets of initial and processed data. The toolbox can be downloaded at: http://www.vuiis.vanderbilt.edu/~truongm/COMA3D/ PMID:25261742

  13. Visualization of 3D Geological Models on Google Earth

    NASA Astrophysics Data System (ADS)

    Choi, Y.; Um, J.; Park, M.

    2013-05-01

    Google Earth combines satellite imagery, aerial photography, thematic maps and various data sets to make a three-dimensional (3D) interactive image of the world. Currently, Google Earth is a popular visualization tool in a variety of fields and plays an increasingly important role not only for private users in daily life, but also for scientists, practitioners, policymakers and stakeholders in research and application. In this study, a method to visualize 3D geological models on Google Earth is presented. COLLAborative Design Activity (COLLADA, an open standard XML schema for establishing interactive 3D applications) was used to represent different 3D geological models such as borehole, fence section, surface-based 3D volume and 3D grid by triangle meshes (a set of triangles connected by their common edges or corners). In addition, we designed Keyhole Markup Language (KML, the XML-based scripting language of Google Earth) codes to import the COLLADA files into the 3D render window of Google Earth. The method was applied to the Grosmont formation in Alberta, Canada. The application showed that the combination of COLLADA and KML enables Google Earth to effectively visualize 3D geological structures and properties.; Visualization of the (a) boreholes, (b) fence sections, (c) 3D volume model and (d) 3D grid model of Grossmont formation on Google Earth

  14. From 3D view to 3D print

    NASA Astrophysics Data System (ADS)

    Dima, M.; Farisato, G.; Bergomi, M.; Viotto, V.; Magrin, D.; Greggio, D.; Farinato, J.; Marafatto, L.; Ragazzoni, R.; Piazza, D.

    2014-08-01

    In the last few years 3D printing is getting more and more popular and used in many fields going from manufacturing to industrial design, architecture, medical support and aerospace. 3D printing is an evolution of bi-dimensional printing, which allows to obtain a solid object from a 3D model, realized with a 3D modelling software. The final product is obtained using an additive process, in which successive layers of material are laid down one over the other. A 3D printer allows to realize, in a simple way, very complex shapes, which would be quite difficult to be produced with dedicated conventional facilities. Thanks to the fact that the 3D printing is obtained superposing one layer to the others, it doesn't need any particular work flow and it is sufficient to simply draw the model and send it to print. Many different kinds of 3D printers exist based on the technology and material used for layer deposition. A common material used by the toner is ABS plastics, which is a light and rigid thermoplastic polymer, whose peculiar mechanical properties make it diffusely used in several fields, like pipes production and cars interiors manufacturing. I used this technology to create a 1:1 scale model of the telescope which is the hardware core of the space small mission CHEOPS (CHaracterising ExOPlanets Satellite) by ESA, which aims to characterize EXOplanets via transits observations. The telescope has a Ritchey-Chrétien configuration with a 30cm aperture and the launch is foreseen in 2017. In this paper, I present the different phases for the realization of such a model, focusing onto pros and cons of this kind of technology. For example, because of the finite printable volume (10×10×12 inches in the x, y and z directions respectively), it has been necessary to split the largest parts of the instrument in smaller components to be then reassembled and post-processed. A further issue is the resolution of the printed material, which is expressed in terms of layers

  15. YouDash3D: exploring stereoscopic 3D gaming for 3D movie theaters

    NASA Astrophysics Data System (ADS)

    Schild, Jonas; Seele, Sven; Masuch, Maic

    2012-03-01

    Along with the success of the digitally revived stereoscopic cinema, events beyond 3D movies become attractive for movie theater operators, i.e. interactive 3D games. In this paper, we present a case that explores possible challenges and solutions for interactive 3D games to be played by a movie theater audience. We analyze the setting and showcase current issues related to lighting and interaction. Our second focus is to provide gameplay mechanics that make special use of stereoscopy, especially depth-based game design. Based on these results, we present YouDash3D, a game prototype that explores public stereoscopic gameplay in a reduced kiosk setup. It features live 3D HD video stream of a professional stereo camera rig rendered in a real-time game scene. We use the effect to place the stereoscopic effigies of players into the digital game. The game showcases how stereoscopic vision can provide for a novel depth-based game mechanic. Projected trigger zones and distributed clusters of the audience video allow for easy adaptation to larger audiences and 3D movie theater gaming.

  16. Speaking Volumes About 3-D

    NASA Technical Reports Server (NTRS)

    2002-01-01

    In 1999, Genex submitted a proposal to Stennis Space Center for a volumetric 3-D display technique that would provide multiple users with a 360-degree perspective to simultaneously view and analyze 3-D data. The futuristic capabilities of the VolumeViewer(R) have offered tremendous benefits to commercial users in the fields of medicine and surgery, air traffic control, pilot training and education, computer-aided design/computer-aided manufacturing, and military/battlefield management. The technology has also helped NASA to better analyze and assess the various data collected by its satellite and spacecraft sensors. Genex capitalized on its success with Stennis by introducing two separate products to the commercial market that incorporate key elements of the 3-D display technology designed under an SBIR contract. The company Rainbow 3D(R) imaging camera is a novel, three-dimensional surface profile measurement system that can obtain a full-frame 3-D image in less than 1 second. The third product is the 360-degree OmniEye(R) video system. Ideal for intrusion detection, surveillance, and situation management, this unique camera system offers a continuous, panoramic view of a scene in real time.

  17. 3-D Printed High Power Microwave Magnetrons

    NASA Astrophysics Data System (ADS)

    Jordan, Nicholas; Greening, Geoffrey; Exelby, Steven; Gilgenbach, Ronald; Lau, Y. Y.; Hoff, Brad

    2015-11-01

    The size, weight, and power requirements of HPM systems are critical constraints on their viability, and can potentially be improved through the use of additive manufacturing techniques, which are rapidly increasing in capability and affordability. Recent experiments on the UM Recirculating Planar Magnetron (RPM), have explored the use of 3-D printed components in a HPM system. The system was driven by MELBA-C, a Marx-Abramyan system which delivers a -300 kV voltage pulse for 0.3-1.0 us, with a 0.15-0.3 T axial magnetic field applied by a pair of electromagnets. Anode blocks were printed from Water Shed XC 11122 photopolymer using a stereolithography process, and prepared with either a spray-coated or electroplated finish. Both manufacturing processes were compared against baseline data for a machined aluminum anode, noting any differences in power output, oscillation frequency, and mode stability. Evolution and durability of the 3-D printed structures were noted both visually and by tracking vacuum inventories via a residual gas analyzer. Research supported by AFOSR (grant #FA9550-15-1-0097) and AFRL.

  18. Macrophage podosomes go 3D.

    PubMed

    Van Goethem, Emeline; Guiet, Romain; Balor, Stéphanie; Charrière, Guillaume M; Poincloux, Renaud; Labrousse, Arnaud; Maridonneau-Parini, Isabelle; Le Cabec, Véronique

    2011-01-01

    Macrophage tissue infiltration is a critical step in the immune response against microorganisms and is also associated with disease progression in chronic inflammation and cancer. Macrophages are constitutively equipped with specialized structures called podosomes dedicated to extracellular matrix (ECM) degradation. We recently reported that these structures play a critical role in trans-matrix mesenchymal migration mode, a protease-dependent mechanism. Podosome molecular components and their ECM-degrading activity have been extensively studied in two dimensions (2D), but yet very little is known about their fate in three-dimensional (3D) environments. Therefore, localization of podosome markers and proteolytic activity were carefully examined in human macrophages performing mesenchymal migration. Using our gelled collagen I 3D matrix model to obligate human macrophages to perform mesenchymal migration, classical podosome markers including talin, paxillin, vinculin, gelsolin, cortactin were found to accumulate at the tip of F-actin-rich cell protrusions together with β1 integrin and CD44 but not β2 integrin. Macrophage proteolytic activity was observed at podosome-like protrusion sites using confocal fluorescence microscopy and electron microscopy. The formation of migration tunnels by macrophages inside the matrix was accomplished by degradation, engulfment and mechanic compaction of the matrix. In addition, videomicroscopy revealed that 3D F-actin-rich protrusions of migrating macrophages were as dynamic as their 2D counterparts. Overall, the specifications of 3D podosomes resembled those of 2D podosome rosettes rather than those of individual podosomes. This observation was further supported by the aspect of 3D podosomes in fibroblasts expressing Hck, a master regulator of podosome rosettes in macrophages. In conclusion, human macrophage podosomes go 3D and take the shape of spherical podosome rosettes when the cells perform mesenchymal migration. This work

  19. 3D Printed Bionic Nanodevices.

    PubMed

    Kong, Yong Lin; Gupta, Maneesh K; Johnson, Blake N; McAlpine, Michael C

    2016-06-01

    The ability to three-dimensionally interweave biological and functional materials could enable the creation of bionic devices possessing unique and compelling geometries, properties, and functionalities. Indeed, interfacing high performance active devices with biology could impact a variety of fields, including regenerative bioelectronic medicines, smart prosthetics, medical robotics, and human-machine interfaces. Biology, from the molecular scale of DNA and proteins, to the macroscopic scale of tissues and organs, is three-dimensional, often soft and stretchable, and temperature sensitive. This renders most biological platforms incompatible with the fabrication and materials processing methods that have been developed and optimized for functional electronics, which are typically planar, rigid and brittle. A number of strategies have been developed to overcome these dichotomies. One particularly novel approach is the use of extrusion-based multi-material 3D printing, which is an additive manufacturing technology that offers a freeform fabrication strategy. This approach addresses the dichotomies presented above by (1) using 3D printing and imaging for customized, hierarchical, and interwoven device architectures; (2) employing nanotechnology as an enabling route for introducing high performance materials, with the potential for exhibiting properties not found in the bulk; and (3) 3D printing a range of soft and nanoscale materials to enable the integration of a diverse palette of high quality functional nanomaterials with biology. Further, 3D printing is a multi-scale platform, allowing for the incorporation of functional nanoscale inks, the printing of microscale features, and ultimately the creation of macroscale devices. This blending of 3D printing, novel nanomaterial properties, and 'living' platforms may enable next-generation bionic systems. In this review, we highlight this synergistic integration of the unique properties of nanomaterials with the

  20. Petal, terrain & airbags - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Portions of the lander's deflated airbags and a petal are at the lower area of this image, taken in stereo by the Imager for Mars Pathfinder (IMP) on Sol 3. 3D glasses are necessary to identify surface detail. The metallic object at lower right is part of the lander's low-gain antenna. This image is part of a 3D 'monster

    Click below to see the left and right views individually. [figure removed for brevity, see original site] Left [figure removed for brevity, see original site] Right

  1. Defragged Binary I Ching Genetic Code Chromosomes Compared to Nirenberg's and Transformed into Rotating 2D Circles and Squares and into a 3D 100% Symmetrical Tetrahedron Coupled to a Functional One to Discern Start From Non-Start Methionines through a Stella Octangula.

    PubMed

    Castro-Chavez, Fernando

    2012-01-01

    BACKGROUND: Three binary representations of the genetic code according to the ancient I Ching of Fu-Xi will be presented, depending on their defragging capabilities by pairing based on three biochemical properties of the nucleic acids: H-bonds, Purine/Pyrimidine rings, and the Keto-enol/Amino-imino tautomerism, yielding the last pair a 32/32 single-strand self-annealed genetic code and I Ching tables. METHODS: Our working tool is the ancient binary I Ching's resulting genetic code chromosomes defragged by vertical and by horizontal pairing, reverse engineered into non-binaries of 2D rotating 4×4×4 circles and 8×8 squares and into one 3D 100% symmetrical 16×4 tetrahedron coupled to a functional tetrahedron with apical signaling and central hydrophobicity (codon formula: 4[1(1)+1(3)+1(4)+4(2)]; 5:5, 6:6 in man) forming a stella octangula, and compared to Nirenberg's 16×4 codon table (1965) pairing the first two nucleotides of the 64 codons in axis y. RESULTS: One horizontal and one vertical defragging had the start Met at the center. Two, both horizontal and vertical pairings produced two pairs of 2×8×4 genetic code chromosomes naturally arranged (M and I), rearranged by semi-introversion of central purines or pyrimidines (M' and I') and by clustering hydrophobic amino acids; their quasi-identity was disrupted by amino acids with odd codons (Met and Tyr pairing to Ile and TGA Stop); in all instances, the 64-grid 90° rotational ability was restored. CONCLUSIONS: We defragged three I Ching representations of the genetic code while emphasizing Nirenberg's historical finding. The synthetic genetic code chromosomes obtained reflect the protective strategy of enzymes with a similar function, having both humans and mammals a biased G-C dominance of three H-bonds in the third nucleotide of their most used codons per amino acid, as seen in one chromosome of the i, M and M' genetic codes, while a two H-bond A-T dominance was found in their complementary chromosome, as

  2. Defragged Binary I Ching Genetic Code Chromosomes Compared to Nirenberg’s and Transformed into Rotating 2D Circles and Squares and into a 3D 100% Symmetrical Tetrahedron Coupled to a Functional One to Discern Start From Non-Start Methionines through a Stella Octangula

    PubMed Central

    Castro-Chavez, Fernando

    2012-01-01

    Background Three binary representations of the genetic code according to the ancient I Ching of Fu-Xi will be presented, depending on their defragging capabilities by pairing based on three biochemical properties of the nucleic acids: H-bonds, Purine/Pyrimidine rings, and the Keto-enol/Amino-imino tautomerism, yielding the last pair a 32/32 single-strand self-annealed genetic code and I Ching tables. Methods Our working tool is the ancient binary I Ching's resulting genetic code chromosomes defragged by vertical and by horizontal pairing, reverse engineered into non-binaries of 2D rotating 4×4×4 circles and 8×8 squares and into one 3D 100% symmetrical 16×4 tetrahedron coupled to a functional tetrahedron with apical signaling and central hydrophobicity (codon formula: 4[1(1)+1(3)+1(4)+4(2)]; 5:5, 6:6 in man) forming a stella octangula, and compared to Nirenberg's 16×4 codon table (1965) pairing the first two nucleotides of the 64 codons in axis y. Results One horizontal and one vertical defragging had the start Met at the center. Two, both horizontal and vertical pairings produced two pairs of 2×8×4 genetic code chromosomes naturally arranged (M and I), rearranged by semi-introversion of central purines or pyrimidines (M' and I') and by clustering hydrophobic amino acids; their quasi-identity was disrupted by amino acids with odd codons (Met and Tyr pairing to Ile and TGA Stop); in all instances, the 64-grid 90° rotational ability was restored. Conclusions We defragged three I Ching representations of the genetic code while emphasizing Nirenberg's historical finding. The synthetic genetic code chromosomes obtained reflect the protective strategy of enzymes with a similar function, having both humans and mammals a biased G-C dominance of three H-bonds in the third nucleotide of their most used codons per amino acid, as seen in one chromosome of the i, M and M' genetic codes, while a two H-bond A-T dominance was found in their complementary chromosome, as seen

  3. RELAP5-3D Developer Guidelines and Programming Practices

    SciTech Connect

    Dr. George L Mesina

    2014-03-01

    Our ultimate goal is to create and maintain RELAP5-3D as the best software tool available to analyze nuclear power plants. This begins with writing excellent programming and requires thorough testing. This document covers development of RELAP5-3D software, the behavior of the RELAP5-3D program that must be maintained, and code testing. RELAP5-3D must perform in a manner consistent with previous code versions with backward compatibility for the sake of the users. Thus file operations, code termination, input and output must remain consistent in form and content while adding appropriate new files, input and output as new features are developed. As computer hardware, operating systems, and other software change, RELAP5-3D must adapt and maintain performance. The code must be thoroughly tested to ensure that it continues to perform robustly on the supported platforms. The coding must be written in a consistent manner that makes the program easy to read to reduce the time and cost of development, maintenance and error resolution. The programming guidelines presented her are intended to institutionalize a consistent way of writing FORTRAN code for the RELAP5-3D computer program that will minimize errors and rework. A common format and organization of program units creates a unifying look and feel to the code. This in turn increases readability and reduces time required for maintenance, development and debugging. It also aids new programmers in reading and understanding the program. Therefore, when undertaking development of the RELAP5-3D computer program, the programmer must write computer code that follows these guidelines. This set of programming guidelines creates a framework of good programming practices, such as initialization, structured programming, and vector-friendly coding. It sets out formatting rules for lines of code, such as indentation, capitalization, spacing, etc. It creates limits on program units, such as subprograms, functions, and modules. It

  4. 3D Hall MHD Reconnection Dynamics

    NASA Astrophysics Data System (ADS)

    Huba, J. D.; Rudakov, L.

    2002-05-01

    A 3D Hall MHD simulation code (VooDoo) has recently been developed at the Naval Research Laboratory. We present preliminary results of a fully 3D magnetic reconnection study using this code. The initial configuration of the plasma system is as follows. The ambient, reversed magnetic field is in the x-direction and is proportional to B0 tanh(y/Ly) where Ly is the scale length of the current sheet. Perturbation fields δ Bx and δ By are introduced to initiate the reconnection process. This initial configuration is similar to that used in the 2D GEM reconnection study. However, the perturbation fields are localized in the z-direction. We consider two cases: no guide field (Bz = 0) and a weak guide field (Bz = 0.1B0). We find that the reconnection process is not stationary in the z-direction but propagates in the B x ∇ n direction consistent with Hall drift physics. Hence, an asymmetric disruption of the current sheet ensues. The flow structure of the plasma in the vicinity of the X-point is complex. We find that the `neutral line' (i.e, along the z-direction) is not an ignorable coordinate and is not periodic in Hall MHD reconnection dynamics; two assumptions that are often made in reconnection studies. \\ Research supported by NASA and ONR

  5. Parallel 3D Finite Element Particle-in-Cell Simulations with Pic3P

    SciTech Connect

    Candel, A.; Kabel, A.; Lee, L.; Li, Z.; Ng, C.; Schussman, G.; Ko, K.; Ben-Zvi, I.; Kewisch, J.; /Brookhaven

    2009-06-19

    SLAC's Advanced Computations Department (ACD) has developed the parallel 3D Finite Element electromagnetic Particle-In-Cell code Pic3P. Designed for simulations of beam-cavity interactions dominated by space charge effects, Pic3P solves the complete set of Maxwell-Lorentz equations self-consistently and includes space-charge, retardation and boundary effects from first principles. Higher-order Finite Element methods with adaptive refinement on conformal unstructured meshes lead to highly efficient use of computational resources. Massively parallel processing with dynamic load balancing enables large-scale modeling of photoinjectors with unprecedented accuracy, aiding the design and operation of next-generation accelerator facilities. Applications include the LCLS RF gun and the BNL polarized SRF gun.

  6. Electromagnetic Surveys for 3-D Imaging of Subsurface Contaminants

    DTIC Science & Technology

    2000-11-01

    testing CVOC chlorinated volatile organic compounds DCA di- chloroacetic acid DCE 1,1 dichloroethane DNAPL Dense Non-Aqueous Phase Liquid DOD Department of...in groundwater samples. Processes in the shop included degreasing, caustic and acid etching, metal stripping and cleaning, and chrome, nickel, silver

  7. The World of 3-D.

    ERIC Educational Resources Information Center

    Mayshark, Robin K.

    1991-01-01

    Students explore three-dimensional properties by creating red and green wall decorations related to Christmas. Students examine why images seem to vibrate when red and green pieces are small and close together. Instructions to conduct the activity and construct 3-D glasses are given. (MDH)

  8. 3D Printing: Exploring Capabilities

    ERIC Educational Resources Information Center

    Samuels, Kyle; Flowers, Jim

    2015-01-01

    As 3D printers become more affordable, schools are using them in increasing numbers. They fit well with the emphasis on product design in technology and engineering education, allowing students to create high-fidelity physical models to see and test different iterations in their product designs. They may also help students to "think in three…

  9. Making Inexpensive 3-D Models

    ERIC Educational Resources Information Center

    Manos, Harry

    2016-01-01

    Visual aids are important to student learning, and they help make the teacher's job easier. Keeping with the "TPT" theme of "The Art, Craft, and Science of Physics Teaching," the purpose of this article is to show how teachers, lacking equipment and funds, can construct a durable 3-D model reference frame and a model gravity…

  10. 2-D Versus 3-D Magnetotelluric Data Interpretation

    NASA Astrophysics Data System (ADS)

    Ledo, Juanjo

    2005-09-01

    In recent years, the number of publications dealing with the mathematical and physical 3-D aspects of the magnetotelluric method has increased drastically. However, field experiments on a grid are often impractical and surveys are frequently restricted to single or widely separated profiles. So, in many cases we find ourselves with the following question: is the applicability of the 2-D hypothesis valid to extract geoelectric and geological information from real 3-D environments? The aim of this paper is to explore a few instructive but general situations to understand the basics of a 2-D interpretation of 3-D magnetotelluric data and to determine which data subset (TE-mode or TM-mode) is best for obtaining the electrical conductivity distribution of the subsurface using 2-D techniques. A review of the mathematical and physical fundamentals of the electromagnetic fields generated by a simple 3-D structure allows us to prioritise the choice of modes in a 2-D interpretation of responses influenced by 3-D structures. This analysis is corroborated by numerical results from synthetic models and by real data acquired by other authors. One important result of this analysis is that the mode most unaffected by 3-D effects depends on the position of the 3-D structure with respect to the regional 2-D strike direction. When the 3-D body is normal to the regional strike, the TE-mode is affected mainly by galvanic effects, while the TM-mode is affected by galvanic and inductive effects. In this case, a 2-D interpretation of the TM-mode is prone to error. When the 3-D body is parallel to the regional 2-D strike the TE-mode is affected by galvanic and inductive effects and the TM-mode is affected mainly by galvanic effects, making it more suitable for 2-D interpretation. In general, a wise 2-D interpretation of 3-D magnetotelluric data can be a guide to a reasonable geological interpretation.

  11. Inferential modeling of 3D chromatin structure.

    PubMed

    Wang, Siyu; Xu, Jinbo; Zeng, Jianyang

    2015-04-30

    For eukaryotic cells, the biological processes involving regulatory DNA elements play an important role in cell cycle. Understanding 3D spatial arrangements of chromosomes and revealing long-range chromatin interactions are critical to decipher these biological processes. In recent years, chromosome conformation capture (3C) related techniques have been developed to measure the interaction frequencies between long-range genome loci, which have provided a great opportunity to decode the 3D organization of the genome. In this paper, we develop a new Bayesian framework to derive the 3D architecture of a chromosome from 3C-based data. By modeling each chromosome as a polymer chain, we define the conformational energy based on our current knowledge on polymer physics and use it as prior information in the Bayesian framework. We also propose an expectation-maximization (EM) based algorithm to estimate the unknown parameters of the Bayesian model and infer an ensemble of chromatin structures based on interaction frequency data. We have validated our Bayesian inference approach through cross-validation and verified the computed chromatin conformations using the geometric constraints derived from fluorescence in situ hybridization (FISH) experiments. We have further confirmed the inferred chromatin structures using the known genetic interactions derived from other studies in the literature. Our test results have indicated that our Bayesian framework can compute an accurate ensemble of 3D chromatin conformations that best interpret the distance constraints derived from 3C-based data and also agree with other sources of geometric constraints derived from experimental evidence in the previous studies. The source code of our approach can be found in https://github.com/wangsy11/InfMod3DGen.

  12. RELAP5-3D Architectural Developments in 2004

    SciTech Connect

    Dr. George L. Mesina

    2004-08-01

    Currently, RELAP5 is undergoing a transformation that will replace much of its coding with equivalent structured Fortran 90 coding. Four efforts are underway to modernize the code architecture of RELAP5-3D. These are parallelization, vectorization, code restructuring, and conversion to Fortran 90. The first two improve code run speed via on computer platforms of certain architectures. These code modifications have little effect on normal code performance on non-vector and non-parallel computers because they are mostly done with compiler directives. The third and fourth efforts involve considerable rewriting of the source code. The third code improvement effort addresses code readability and maintainability. These are being greatly enhanced by application of a Fortran code-restructuring tool. The fourth effort is conversion to Fortran 90. The bulk of the coding is being rewritten in Fortran 90. This is a ground up reworking of the coding that begins with completely reorganizing the underlying database and continues with the source code. It will reach every part of RELAP5-3D. Each of these efforts is discussed in detail in a different section. Section 1 relates background information. Section 2 covers the parallelization effort. Section 3 covers the efforts to vectorize the code. Section 4 covers the code restructuring. Section 5 covers the Fortran 90 effort. Outline Background: longevity, maintenance & development, reliability, speed Parallelization: KAI to OpenMP, previous work & current, domain decomposition, done. Vectorization: Speed - Fed init, vectors in PCs, INL Cray SV1, R5 Phant, EXV, results. Code Restructuring: Reason to restructure, study of restruct, For Study: what it does, Fortran 90: Modernization -

  13. FUN3D and CFL3D Computations for the First High Lift Prediction Workshop

    NASA Technical Reports Server (NTRS)

    Park, Michael A.; Lee-Rausch, Elizabeth M.; Rumsey, Christopher L.

    2011-01-01

    Two Reynolds-averaged Navier-Stokes codes were used to compute flow over the NASA Trapezoidal Wing at high lift conditions for the 1st AIAA CFD High Lift Prediction Workshop, held in Chicago in June 2010. The unstructured-grid code FUN3D and the structured-grid code CFL3D were applied to several different grid systems. The effects of code, grid system, turbulence model, viscous term treatment, and brackets were studied. The SST model on this configuration predicted lower lift than the Spalart-Allmaras model at high angles of attack; the Spalart-Allmaras model agreed better with experiment. Neglecting viscous cross-derivative terms caused poorer prediction in the wing tip vortex region. Output-based grid adaptation was applied to the unstructured-grid solutions. The adapted grids better resolved wake structures and reduced flap flow separation, which was also observed in uniform grid refinement studies. Limitations of the adaptation method as well as areas for future improvement were identified.

  14. 3D Equilibrium Reconstruction in Stellarators and Tokamaks with STELLOPT

    NASA Astrophysics Data System (ADS)

    Lazerson, Samuel; Pablant, Novimir; Gates, David; Neilson, Hutch; Nazikian, Raffi; Suzuki, Yasuhiro; Watanabe, Kiyomasa; Ida, Katsumi; Sakakibara, Satoru

    2012-10-01

    The ability to model and predict the behavior of stellarators and tokamaks requires an ability to match simulation parameters with experimental measurements. This process, known as experimental reconstruction, has been used extensively with 2D axisymmetric codes for Tokamaks. These codes, such as EFIT, lack the ability to model the 3D nature of stellarators and the emerging 3D nature of Tokamaks. Phenomena such as, shielding of islands by neoclassical flows and the suppression of edge localized modes through application of 3D fields, highlight the need for such 3D tools. The stellarator optimizer code STELLOPT has been modified to match 3D VMEC equilibria to experimental measurements. This has allowed 3D experimental reconstructions to be preformed on W7-AS, LHD, and DIII-D devices. The free boundary VMEC equilibria are matched to Thomson profiles (ne and Te), charge exchange measurements (Ti), MSE (polarization angle), and magnetic diagnostics (B-probes, flux loops, Rogowski coils). Three dimensional reconstructed equilibria are presented alongside confidence metrics for the reconstruction process.

  15. USM3D Predictions of Supersonic Nozzle Flow

    NASA Technical Reports Server (NTRS)

    Carter, Melissa B.; Elmiligui, Alaa A.; Campbell, Richard L.; Nayani, Sudheer N.

    2014-01-01

    This study focused on the NASA Tetrahedral Unstructured Software System CFD code (USM3D) capability to predict supersonic plume flow. Previous studies, published in 2004 and 2009, investigated USM3D's results versus historical experimental data. This current study continued that comparison however focusing on the use of the volume souring to capture the shear layers and internal shock structure of the plume. This study was conducted using two benchmark axisymmetric supersonic jet experimental data sets. The study showed that with the use of volume sourcing, USM3D was able to capture and model a jet plume's shear layer and internal shock structure.

  16. Forensic 3D scene reconstruction

    NASA Astrophysics Data System (ADS)

    Little, Charles Q.; Small, Daniel E.; Peters, Ralph R.; Rigdon, J. B.

    2000-05-01

    Traditionally law enforcement agencies have relied on basic measurement and imaging tools, such as tape measures and cameras, in recording a crime scene. A disadvantage of these methods is that they are slow and cumbersome. The development of a portable system that can rapidly record a crime scene with current camera imaging, 3D geometric surface maps, and contribute quantitative measurements such as accurate relative positioning of crime scene objects, would be an asset to law enforcement agents in collecting and recording significant forensic data. The purpose of this project is to develop a fieldable prototype of a fast, accurate, 3D measurement and imaging system that would support law enforcement agents to quickly document and accurately record a crime scene.

  17. 3D Printed Robotic Hand

    NASA Technical Reports Server (NTRS)

    Pizarro, Yaritzmar Rosario; Schuler, Jason M.; Lippitt, Thomas C.

    2013-01-01

    Dexterous robotic hands are changing the way robots and humans interact and use common tools. Unfortunately, the complexity of the joints and actuations drive up the manufacturing cost. Some cutting edge and commercially available rapid prototyping machines now have the ability to print multiple materials and even combine these materials in the same job. A 3D model of a robotic hand was designed using Creo Parametric 2.0. Combining "hard" and "soft" materials, the model was printed on the Object Connex350 3D printer with the purpose of resembling as much as possible the human appearance and mobility of a real hand while needing no assembly. After printing the prototype, strings where installed as actuators to test mobility. Based on printing materials, the manufacturing cost of the hand was $167, significantly lower than other robotic hands without the actuators since they have more complex assembly processes.

  18. Comparing swimsuits in 3D.

    PubMed

    van Geer, Erik; Molenbroek, Johan; Schreven, Sander; deVoogd-Claessen, Lenneke; Toussaint, Huib

    2012-01-01

    In competitive swimming, suits have become more important. These suits influence friction, pressure and wave drag. Friction drag is related to the surface properties whereas both pressure and wave drag are greatly influenced by body shape. To find a relationship between the body shape and the drag, the anthropometry of several world class female swimmers wearing different suits was accurately defined using a 3D scanner and traditional measuring methods. The 3D scans delivered more detailed information about the body shape. On the same day the swimmers did performance tests in the water with the tested suits. Afterwards the result of the performance tests and the differences found in body shape was analyzed to determine the deformation caused by a swimsuit and its effect on the swimming performance. Although the amount of data is limited because of the few test subjects, there is an indication that the deformation of the body influences the swimming performance.

  19. Forensic 3D Scene Reconstruction

    SciTech Connect

    LITTLE,CHARLES Q.; PETERS,RALPH R.; RIGDON,J. BRIAN; SMALL,DANIEL E.

    1999-10-12

    Traditionally law enforcement agencies have relied on basic measurement and imaging tools, such as tape measures and cameras, in recording a crime scene. A disadvantage of these methods is that they are slow and cumbersome. The development of a portable system that can rapidly record a crime scene with current camera imaging, 3D geometric surface maps, and contribute quantitative measurements such as accurate relative positioning of crime scene objects, would be an asset to law enforcement agents in collecting and recording significant forensic data. The purpose of this project is to develop a feasible prototype of a fast, accurate, 3D measurement and imaging system that would support law enforcement agents to quickly document and accurately record a crime scene.

  20. 3D-graphite structure

    SciTech Connect

    Belenkov, E. A. Ali-Pasha, V. A.

    2011-01-15

    The structure of clusters of some new carbon 3D-graphite phases have been calculated using the molecular-mechanics methods. It is established that 3D-graphite polytypes {alpha}{sub 1,1}, {alpha}{sub 1,3}, {alpha}{sub 1,5}, {alpha}{sub 2,1}, {alpha}{sub 2,3}, {alpha}{sub 3,1}, {beta}{sub 1,2}, {beta}{sub 1,4}, {beta}{sub 1,6}, {beta}{sub 2,1}, and {beta}{sub 3,2} consist of sp{sup 2}-hybridized atoms, have hexagonal unit cells, and differ in regards to the structure of layers and order of their alternation. A possible way to experimentally synthesize new carbon phases is proposed: the polymerization and carbonization of hydrocarbon molecules.

  1. 3-D QSAutogrid/R: an alternative procedure to build 3-D QSAR models. Methodologies and applications.

    PubMed

    Ballante, Flavio; Ragno, Rino

    2012-06-25

    Since it first appeared in 1988 3-D QSAR has proved its potential in the field of drug design and activity prediction. Although thousands of citations now exist in 3-D QSAR, its development was rather slow with the majority of new 3-D QSAR applications just extensions of CoMFA. An alternative way to build 3-D QSAR models, based on an evolution of software, has been named 3-D QSAutogrid/R and has been developed to use only software freely available to academics. 3-D QSAutogrid/R covers all the main features of CoMFA and GRID/GOLPE with implementation by multiprobe/multiregion variable selection (MPGRS) that improves the simplification of interpretation of the 3-D QSAR map. The methodology is based on the integration of the molecular interaction fields as calculated by AutoGrid and the R statistical environment that can be easily coupled with many free graphical molecular interfaces such as UCSF-Chimera, AutoDock Tools, JMol, and others. The description of each R package is reported in detail, and, to assess its validity, 3-D QSAutogrid/R has been applied to three molecular data sets of which either CoMFA or GRID/GOLPE models were reported in order to compare the results. 3-D QSAutogrid/R has been used as the core engine to prepare more that 240 3-D QSAR models forming the very first 3-D QSAR server ( www.3d-qsar.com ) with its code freely available through R-Cran distribution.

  2. [Real time 3D echocardiography

    NASA Technical Reports Server (NTRS)

    Bauer, F.; Shiota, T.; Thomas, J. D.

    2001-01-01

    Three-dimensional representation of the heart is an old concern. Usually, 3D reconstruction of the cardiac mass is made by successive acquisition of 2D sections, the spatial localisation and orientation of which require complex guiding systems. More recently, the concept of volumetric acquisition has been introduced. A matricial emitter-receiver probe complex with parallel data processing provides instantaneous of a pyramidal 64 degrees x 64 degrees volume. The image is restituted in real time and is composed of 3 planes (planes B and C) which can be displaced in all spatial directions at any time during acquisition. The flexibility of this system of acquisition allows volume and mass measurement with greater accuracy and reproducibility, limiting inter-observer variability. Free navigation of the planes of investigation allows reconstruction for qualitative and quantitative analysis of valvular heart disease and other pathologies. Although real time 3D echocardiography is ready for clinical usage, some improvements are still necessary to improve its conviviality. Then real time 3D echocardiography could be the essential tool for understanding, diagnosis and management of patients.

  3. 3-D Ultrasound Guidance of Autonomous Robot for Location of Ferrous Shrapnel

    PubMed Central

    Rogers, Albert J.; Light, Edward D.

    2010-01-01

    Vibrations can be induced in ferromagnetic shrapnel by a variable electromagnet. Real time 3-D color Doppler ultrasound located the induced motion in a needle fragment and determined its 3-D position in the scanner coordinates. This information was used to guide a robot which moved a probe to touch the shrapnel fragment. PMID:19574140

  4. 3-D ultrasound guidance of autonomous robot for location of ferrous shrapnel.

    PubMed

    Rogers, Albert J; Light, Edward D; Smith, Stephen W

    2009-07-01

    Vibrations can be induced in ferromagnetic shrapnel by a variable electromagnet. Real time 3-D color Doppler ultrasound located the induced motion in a needle fragment and determined its 3-D position in the scanner coordinates. This information was used to guide a robot which moved a probe to touch the shrapnel fragment.

  5. GPU-Accelerated Denoising in 3D (GD3D)

    SciTech Connect

    2013-10-01

    The raw computational power GPU Accelerators enables fast denoising of 3D MR images using bilateral filtering, anisotropic diffusion, and non-local means. This software addresses two facets of this promising application: what tuning is necessary to achieve optimal performance on a modern GPU? And what parameters yield the best denoising results in practice? To answer the first question, the software performs an autotuning step to empirically determine optimal memory blocking on the GPU. To answer the second, it performs a sweep of algorithm parameters to determine the combination that best reduces the mean squared error relative to a noiseless reference image.

  6. Joint inversions of two VTEM surveys using quasi-3D TDEM and 3D magnetic inversion algorithms

    NASA Astrophysics Data System (ADS)

    Kaminski, Vlad; Di Massa, Domenico; Viezzoli, Andrea

    2016-05-01

    In the current paper, we present results of a joint quasi-three-dimensional (quasi-3D) inversion of two versatile time domain electromagnetic (VTEM) datasets, as well as a joint 3D inversion of associated aeromagnetic datasets, from two surveys flown six years apart from one another (2007 and 2013) over a volcanogenic massive sulphide gold (VMS-Au) prospect in northern Ontario, Canada. The time domain electromagnetic (TDEM) data were inverted jointly using the spatially constrained inversion (SCI) approach. In order to increase the coherency in the model space, a calibration parameter was added. This was followed by a joint inversion of the total magnetic intensity (TMI) data extracted from the two surveys. The results of the inversions have been studied and matched with the known geology, adding some new valuable information to the ongoing mineral exploration initiative.

  7. Reactor transient analyses with KIN3D/PARTISN

    SciTech Connect

    Gabrielli, F.; Rineiski, A.; Maschek, W.; Marchetti, M.

    2013-07-01

    Efforts are going on at the Karlsruhe Institute of Technology (KIT) to extend the kinetics capability of the PARTISN code in order to run in parallel two- and three-dimensional transient analyses with the quasistatic method, while taking into account delayed neutrons. In the original code version, time-dependent transport problems are solved by employing a semi-implicit direct kinetics option, the delayed neutrons being not taken into account. The PARTISN 5.97 code has been extended and then coupled with KIN3D, a time-dependent model embedded in the ERANOS code system. In the coupled code, PARTISN 5.97 is used as neutron transport solver to perform transient analyses while employing direct and quasi-static kinetics options of KIN3D. The coupled code can be also applied for first-order and exact perturbation theory calculations. In the paper, the PARTISN 5.97 extensions and coupling procedure are described and the performances of the KIN3D/PARTISN coupled code are investigated by analyzing transients induced by a source-jerk in a three-dimensional ADS model driven by an external source. (authors)

  8. Extremely accurate sequential verification of RELAP5-3D

    SciTech Connect

    Mesina, George L.; Aumiller, David L.; Buschman, Francis X.

    2015-11-19

    Large computer programs like RELAP5-3D solve complex systems of governing, closure and special process equations to model the underlying physics of nuclear power plants. Further, these programs incorporate many other features for physics, input, output, data management, user-interaction, and post-processing. For software quality assurance, the code must be verified and validated before being released to users. For RELAP5-3D, verification and validation are restricted to nuclear power plant applications. Verification means ensuring that the program is built right by checking that it meets its design specifications, comparing coding to algorithms and equations and comparing calculations against analytical solutions and method of manufactured solutions. Sequential verification performs these comparisons initially, but thereafter only compares code calculations between consecutive code versions to demonstrate that no unintended changes have been introduced. Recently, an automated, highly accurate sequential verification method has been developed for RELAP5-3D. The method also provides to test that no unintended consequences result from code development in the following code capabilities: repeating a timestep advancement, continuing a run from a restart file, multiple cases in a single code execution, and modes of coupled/uncoupled operation. In conclusion, mathematical analyses of the adequacy of the checks used in the comparisons are provided.

  9. Extremely accurate sequential verification of RELAP5-3D

    DOE PAGES

    Mesina, George L.; Aumiller, David L.; Buschman, Francis X.

    2015-11-19

    Large computer programs like RELAP5-3D solve complex systems of governing, closure and special process equations to model the underlying physics of nuclear power plants. Further, these programs incorporate many other features for physics, input, output, data management, user-interaction, and post-processing. For software quality assurance, the code must be verified and validated before being released to users. For RELAP5-3D, verification and validation are restricted to nuclear power plant applications. Verification means ensuring that the program is built right by checking that it meets its design specifications, comparing coding to algorithms and equations and comparing calculations against analytical solutions and method ofmore » manufactured solutions. Sequential verification performs these comparisons initially, but thereafter only compares code calculations between consecutive code versions to demonstrate that no unintended changes have been introduced. Recently, an automated, highly accurate sequential verification method has been developed for RELAP5-3D. The method also provides to test that no unintended consequences result from code development in the following code capabilities: repeating a timestep advancement, continuing a run from a restart file, multiple cases in a single code execution, and modes of coupled/uncoupled operation. In conclusion, mathematical analyses of the adequacy of the checks used in the comparisons are provided.« less

  10. Reaction induced fractures in 3D

    NASA Astrophysics Data System (ADS)

    Ulven, Ole Ivar; Malthe-Sørenssen, Anders

    2014-05-01

    The process of fracture formation due to volume changing processes has been studied numerically in a variety of different settings, e.g. fracture initiation in general volume increasing reactions by Ulven et al.[4], weathering of dolerites by Røyne et al.[2], and volume reduction during chemical decomposition prosesses by Malthe-Sørenssen et al.[1]. Common to many previous works is that the simulations were performed in a 2D setting, due to computational limitations. Fractures observed both in field studies and in experiments are in many cases three dimensional. It remains an open question in what cases the simplification to 2D systems is applicable, and when a full 3D simulation is necessary. In this study, we use a newly developed 3D code combining elements from the discrete element model (DEM) with elements from Peridynamics[3]. We study fracture formation in fully three dimensional simulations, and compare them with simulation results from 2D DEM, thus gaining insight in both qualitative and quantitative differences between results from 2D and 3D simulations. References [1] Malthe-Sørenssen, A., Jamtveit, B., and Meakin, P., 'Fracture Patterns Generated by Diffusion Controlled Volume Changing Reactions,' Phys. Rev. Lett. 96, 2006, pp. 245501-1 - 245501-4. [2] Røyne, A., Jamtveit, B., and Malthe-Sørenssen, A., 'Controls on rock weathering rates by reaction-induced hierarchial fracturing,' Earth Planet. Sci. Lett. 275, 2008, pp. 364 - 369. [3] Silling, S. A., 'Reformulation of elasticity theory for discontinuities and long-range forces,' J. Mech. Phys. Solids, 48, Issue 1, 2000, pp. 175 - 209 [4] Ulven, O. I., Storheim, H., Austrheim, H., and Malthe-Sørenssen, A., 'Fracture Initiation During Volume Increasing Reactions in Rocks and Applications for CO2 Sequestration', Earth Planet. Sci. Lett. 389C, 2014, pp. 132 - 142.

  11. Interactive 3D Mars Visualization

    NASA Technical Reports Server (NTRS)

    Powell, Mark W.

    2012-01-01

    The Interactive 3D Mars Visualization system provides high-performance, immersive visualization of satellite and surface vehicle imagery of Mars. The software can be used in mission operations to provide the most accurate position information for the Mars rovers to date. When integrated into the mission data pipeline, this system allows mission planners to view the location of the rover on Mars to 0.01-meter accuracy with respect to satellite imagery, with dynamic updates to incorporate the latest position information. Given this information so early in the planning process, rover drivers are able to plan more accurate drive activities for the rover than ever before, increasing the execution of science activities significantly. Scientifically, this 3D mapping information puts all of the science analyses to date into geologic context on a daily basis instead of weeks or months, as was the norm prior to this contribution. This allows the science planners to judge the efficacy of their previously executed science observations much more efficiently, and achieve greater science return as a result. The Interactive 3D Mars surface view is a Mars terrain browsing software interface that encompasses the entire region of exploration for a Mars surface exploration mission. The view is interactive, allowing the user to pan in any direction by clicking and dragging, or to zoom in or out by scrolling the mouse or touchpad. This set currently includes tools for selecting a point of interest, and a ruler tool for displaying the distance between and positions of two points of interest. The mapping information can be harvested and shared through ubiquitous online mapping tools like Google Mars, NASA WorldWind, and Worldwide Telescope.

  12. 3D Nanostructuring of Semiconductors

    NASA Astrophysics Data System (ADS)

    Blick, Robert

    2000-03-01

    Modern semiconductor technology allows to machine devices on the nanometer scale. I will discuss the current limits of the fabrication processes, which enable the definition of single electron transistors with dimensions down to 8 nm. In addition to the conventional 2D patterning and structuring of semiconductors, I will demonstrate how to apply 3D nanostructuring techniques to build freely suspended single-crystal beams with lateral dimension down to 20 nm. In transport measurements in the temperature range from 30 mK up to 100 K these nano-crystals are characterized regarding their electronic as well as their mechanical properties. Moreover, I will present possible applications of these devices.

  13. What Lies Ahead (3-D)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This 3-D cylindrical-perspective mosaic taken by the navigation camera on the Mars Exploration Rover Spirit on sol 82 shows the view south of the large crater dubbed 'Bonneville.' The rover will travel toward the Columbia Hills, seen here at the upper left. The rock dubbed 'Mazatzal' and the hole the rover drilled in to it can be seen at the lower left. The rover's position is referred to as 'Site 22, Position 32.' This image was geometrically corrected to make the horizon appear flat.

  14. Making Inexpensive 3-D Models

    NASA Astrophysics Data System (ADS)

    Manos, Harry

    2016-03-01

    Visual aids are important to student learning, and they help make the teacher's job easier. Keeping with the TPT theme of "The Art, Craft, and Science of Physics Teaching," the purpose of this article is to show how teachers, lacking equipment and funds, can construct a durable 3-D model reference frame and a model gravity well tailored to specific class lessons. Most of the supplies are readily available in the home or at school: rubbing alcohol, a rag, two colors of spray paint, art brushes, and masking tape. The cost of these supplies, if you don't have them, is less than 20.

  15. A Clean Adirondack (3-D)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is a 3-D anaglyph showing a microscopic image taken of an area measuring 3 centimeters (1.2 inches) across on the rock called Adirondack. The image was taken at Gusev Crater on the 33rd day of the Mars Exploration Rover Spirit's journey (Feb. 5, 2004), after the rover used its rock abrasion tool brush to clean the surface of the rock. Dust, which was pushed off to the side during cleaning, can still be seen to the left and in low areas of the rock.

  16. 3D Printed Shelby Cobra

    SciTech Connect

    Love, Lonnie

    2015-01-09

    ORNL's newly printed 3D Shelby Cobra was showcased at the 2015 NAIAS in Detroit. This "laboratory on wheels" uses the Shelby Cobra design, celebrating the 50th anniversary of this model and honoring the first vehicle to be voted a national monument. The Shelby was printed at the Department of Energy’s Manufacturing Demonstration Facility at ORNL using the BAAM (Big Area Additive Manufacturing) machine and is intended as a “plug-n-play” laboratory on wheels. The Shelby will allow research and development of integrated components to be tested and enhanced in real time, improving the use of sustainable, digital manufacturing solutions in the automotive industry.

  17. Backhoe 3D "gold standard" image

    NASA Astrophysics Data System (ADS)

    Gorham, LeRoy; Naidu, Kiranmai D.; Majumder, Uttam; Minardi, Michael A.

    2005-05-01

    ViSUAl-D (VIsual Sar Using ALl Dimensions), a 2004 DARPA/IXO seedling effort, is developing a capability for reliable high confidence ID from standoff ranges. Recent conflicts have demonstrated that the warfighter would greatly benefit from the ability to ID targets beyond visual and electro-optical ranges[1]. Forming optical-quality SAR images while exploiting full polarization, wide angles, and large bandwidth would be key evidence such a capability is achievable. Using data generated by the Xpatch EM scattering code, ViSUAl-D investigates all degrees of freedom available to the radar designer, including 6 GHz bandwidth, full polarization and angle sampling over 2π steradians (upper hemisphere), in order to produce a "literal" image or representation of the target. This effort includes the generation of a "Gold Standard" image that can be produced at X-band utilizing all available target data. This "Gold Standard" image of the backhoe will serve as a test bed for future more relevant military targets and their image development. The seedling team produced a public release data which was released at the 2004 SPIE conference, as well as a 3D "Gold Standard" backhoe image using a 3D image formation algorithm. This paper describes the full backhoe data set, the image formation algorithm, the visualization process and the resulting image.

  18. Positional Awareness Map 3D (PAM3D)

    NASA Technical Reports Server (NTRS)

    Hoffman, Monica; Allen, Earl L.; Yount, John W.; Norcross, April Louise

    2012-01-01

    The Western Aeronautical Test Range of the National Aeronautics and Space Administration s Dryden Flight Research Center needed to address the aging software and hardware of its current situational awareness display application, the Global Real-Time Interactive Map (GRIM). GRIM was initially developed in the late 1980s and executes on older PC architectures using a Linux operating system that is no longer supported. Additionally, the software is difficult to maintain due to its complexity and loss of developer knowledge. It was decided that a replacement application must be developed or acquired in the near future. The replacement must provide the functionality of the original system, the ability to monitor test flight vehicles in real-time, and add improvements such as high resolution imagery and true 3-dimensional capability. This paper will discuss the process of determining the best approach to replace GRIM, and the functionality and capabilities of the first release of the Positional Awareness Map 3D.

  19. 3D printed bionic ears.

    PubMed

    Mannoor, Manu S; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A; Soboyejo, Winston O; Verma, Naveen; Gracias, David H; McAlpine, Michael C

    2013-06-12

    The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing.

  20. 3D Printable Graphene Composite

    PubMed Central

    Wei, Xiaojun; Li, Dong; Jiang, Wei; Gu, Zheming; Wang, Xiaojuan; Zhang, Zengxing; Sun, Zhengzong

    2015-01-01

    In human being’s history, both the Iron Age and Silicon Age thrived after a matured massive processing technology was developed. Graphene is the most recent superior material which could potentially initialize another new material Age. However, while being exploited to its full extent, conventional processing methods fail to provide a link to today’s personalization tide. New technology should be ushered in. Three-dimensional (3D) printing fills the missing linkage between graphene materials and the digital mainstream. Their alliance could generate additional stream to push the graphene revolution into a new phase. Here we demonstrate for the first time, a graphene composite, with a graphene loading up to 5.6 wt%, can be 3D printable into computer-designed models. The composite’s linear thermal coefficient is below 75 ppm·°C−1 from room temperature to its glass transition temperature (Tg), which is crucial to build minute thermal stress during the printing process. PMID:26153673