WorldWideScience

Sample records for fast forward-field calculation

  1. Development of Fast running DNBR Calculation Code

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Hyuk; Seo, K. W.; Kim, S. J.; Hwang, D. H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-10-15

    SMART core adopted a core protection(SCOPS) and a supervising system(SCOMS) to satisfy the SAFDL for AOO and normal operation. Generally, the criteria is limited to the DNBR limit so that the DNBR calculation module is required in the protection and the supervising system of core. There are CPU time limit and calculation robustness as some requirements of the DNBR calculation module in SCOPS and SCOMS caused by hardware limitations. The non-iterative few channel methods are needed to satisfy the requirements. Non-iterative numerical method is similar to the CETOP algorithm originated from ref. 1. The method is known as the non-iterative prediction and correction method. An optimum number of channels for core lumping model is selected as 4- channel which is same channel number of CETOP model. A compensation model of lumped channel is needed to ensure that the 4-channel thermal hydraulic field is nearly equivalent to that field of 1/8-core model that is calculated by MATRA-S. The code called FAST that is fast running DNBR calculation is developed to satisfy the requirements of CPU time and calculation robustness. Present paper is described of characteristics and calculation results of developed FAST code

  2. Fast Electron Beam Simulation and Dose Calculation

    CERN Document Server

    Trindade, A; Peralta, L; Lopes, M C; Alves, C; Chaves, A

    2003-01-01

    A flexible multiple source model capable of fast reconstruction of clinical electron beams is presented in this paper. A source model considers multiple virtual sources emulating the effect of accelerator head components. A reference configuration (10 MeV and 10x10 cm2 field size) for a Siemens KD2 linear accelerator was simulated in full detail using GEANT3 Monte Carlo code. Our model allows the reconstruction of other beam energies and field sizes as well as other beam configurations for similar accelerators using only the reference beam data. Electron dose calculations were performed with the reconstructed beams in a water phantom and compared with experimental data. An agreement of 1-2% / 1-2 mm was obtained, equivalent to the accuracy of full Monte Carlo accelerator simulation. The source model reduces accelerator simulation CPU time by a factor of 7500 relative to full Monte Carlo approaches. The developed model was then interfaced with DPM, a fast radiation transport Monte Carlo code for dose calculati...

  3. Improvement of Neutronics Calculation Methods for Fast Reactors

    OpenAIRE

    Takeda, Toshikazu

    2011-01-01

    To accurately estimate neutronics properties of fast reactors, particularly Japan Sodium-cooled Fast Reactor of1,500 MW electric, calculational methods are being improved in Japan.This paper describes the planning and the ongoing development of the neutronics calculation methods in the fieldof 1) assembly calculations including the calculations of effective cross sections, 2) core calculations and 3) uncertaintyevaluation and uncertainty reduction.

  4. Fast variation method for elastic strip calculation.

    Science.gov (United States)

    Biryukov, Sergey V

    2002-05-01

    A new, fast, variation method (FVM) for determining an elastic strip response to stresses arbitrarily distributed on the flat side of the strip is proposed. The remaining surface of the strip may have an arbitrary form, and it is free of stresses. The FVM, as well as the well-known finite element method (FEM), starts with the variational principle. However, it does not use the meshing of the strip. A comparison of FVM results with the exact analytical solution in the special case of shear stresses and a rectangular strip demonstrates an excellent agreement.

  5. Fastlim: a fast LHC limit calculator.

    Science.gov (United States)

    Papucci, Michele; Sakurai, Kazuki; Weiler, Andreas; Zeune, Lisa

    Fastlim is a tool to calculate conservative limits on extensions of the Standard Model from direct LHC searches without performing any Monte Carlo event generation. The program reconstructs the visible cross sections (cross sections after event selection cuts) from pre-calculated efficiency tables and cross section tables for simplified event topologies. As a proof of concept of the approach, we have implemented searches relevant for supersymmetric models with R-parity conservation. Fastlim takes the spectrum and coupling information of a given model point and provides, for each signal region of the implemented analyses, the visible cross sections normalised to the corresponding upper limit, reported by the experiments, as well as the [Formula: see text] value. To demonstrate the utility of the program we study the sensitivity of the recent ATLAS missing energy searches to the parameter space of natural SUSY models. The program structure allows the straightforward inclusion of external efficiency tables and can be generalised to R-parity violating scenarios and non-SUSY models. This paper serves as a self-contained user guide and indicates the conventions and approximations used.

  6. Fastlim. A fast LHC limit calculator

    Energy Technology Data Exchange (ETDEWEB)

    Papucci, Michele [Michigan Univ., Ann Arbor, MI (United States). Michigan Center for Theoretical Physics; Sakurai, Kazuki [King' s College London (United Kingdom). Physics Dept.; Weiler, Andreas [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Zeune, Lisa [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2014-02-15

    Fastlim is a tool to calculate conservative limits on extensions of the Standard Model from direct LHC searches without performing any Monte Carlo event generation. The program reconstructs the visible cross sections from pre-calculated efficiency tables and cross section tables for simplified event topologies. As a proof of concept of the approach, we have implemented searches relevant for supersymmetric models with R-parity conservation. Fastlim takes the spectrum and coupling information of a given model point and provides, for each signal region of the implemented analyses, the visible cross sections normalised to the corresponding upper limit, reported by the experiments, as well as the exclusion p-value. To demonstrate the utility of the program we study the sensitivity of the recent ATLAS missing energy searches to the parameter space of natural SUSY models. The program structure allows the straight-forward inclusion of external efficiency tables and can be generalised to R-parity violating scenarios and non-SUSY models. This paper serves as a self-contained user guide, and indicates the conventions and approximations used.

  7. Fastlim: a fast LHC limit calculator

    Energy Technology Data Exchange (ETDEWEB)

    Papucci, Michele [University of Michigan, Michigan Center for Theoretical Physics, Ann Arbor, MI (United States); Sakurai, Kazuki [King' s College London, Physics Department, London (United Kingdom); Weiler, Andreas [CERN TH-PH Division, Meyrin (Switzerland); Zeune, Lisa [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany)

    2014-11-15

    Fastlim is a tool to calculate conservative limits on extensions of the Standard Model from direct LHC searches without performing any Monte Carlo event generation. The program reconstructs the visible cross sections (cross sections after event selection cuts) from pre-calculated efficiency tables and cross section tables for simplified event topologies. As a proof of concept of the approach, we have implemented searches relevant for supersymmetric models with R-parity conservation. Fastlim takes the spectrum and coupling information of a given model point and provides, for each signal region of the implemented analyses, the visible cross sections normalised to the corresponding upper limit, reported by the experiments, as well as the CL{sub s} value. To demonstrate the utility of the program we study the sensitivity of the recent ATLAS missing energy searches to the parameter space of natural SUSY models. The program structure allows the straightforward inclusion of external efficiency tables and can be generalised to R-parity violating scenarios and non-SUSY models. This paper serves as a self-contained user guide and indicates the conventions and approximations used. (orig.)

  8. Fast calculation of the best focus position

    Science.gov (United States)

    Bezzubik, Vitalii; Belashenkov, Nikolai; Vdovin, Gleb

    2015-03-01

    New computational technique based on linear-scale differential analysis (LSDA) of digital image is proposed to find the best focus position in digital microscopy by means of defocus estimation in two near-focal positions only. The method is based on the calculation of local gradients of the image on different scales using its convolution with a number of differential filters of linearly varying sizes, consequent removal of noisy pixels out of consideration, and selection of pixels at the edges of objects. It is shown that the mean values of the selected gradients decrease while the scale increases thus the rate of change of these mean values of gradients unambiguously determines the magnitude of digital image defocus as a function of scale. Using this method the value and sign of defocus can be found if the result of LSDA of captured images is compared with pre-defined look-up table. The robustness of the proposed method to spatial noise is achieved by ignoring pixels that are corrupted by spatial noise within the areas of the image outside the edges of objects. Most computational operations of the method are based on integer arithmetic that simplifies its practical implementation and significantly improves the performance. The latter aspect is particularly important for practical use in real-time imaging systems.

  9. A fast multipole transformation for global climate calculations

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, J.A.; Wang, Z.; Drake, J.B.; Lyon, B.F.; Chen, W.T.

    1996-01-01

    A fast multipole transformation is adapted to the evaluation of summations that occur in global climate calculations when transforming between spatial and spherical harmonic representations. For each summation, the timing of the fast multipole transformation scales linearly with the number of latitude gridpoints, but the timing for direct evaluations scales quadratically. In spite of a larger computational overhead, this scaling advantage renders the fast multipole method faster than direct evaluation for transformations involving greater than approximately 300 to 500 gridpoints. Convergence of the fast multipole transformation is accurate to machine precision. As the resolution in global climate calculations continues to increase, an increasingly large fraction of the computational work involves the transformation between spatial and spherical harmonic representations. The fast multipole transformation offers a significant reduction in computational time for these high-resolution cases.

  10. Fast dose calculation in magnetic fields with GPUMCD

    Energy Technology Data Exchange (ETDEWEB)

    Hissoiny, S; Ozell, B [Ecole Polytechnique de Montreal, Departement de genie informatique et genie logiciel, 2500 Chemin de Polytechnique, Montreal, Quebec H3T 1J4 (Canada); Raaijmakers, A J E; Raaymakers, B W [Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht (Netherlands); Despres, P, E-mail: sami.hissoiny@polymtl.ca [Departement de physique, Universite Laval, Quebec (Canada)

    2011-08-21

    A new hybrid imaging-treatment modality, the MRI-Linac, involves the irradiation of the patient in the presence of a strong magnetic field. This field acts on the charged particles, responsible for depositing dose, through the Lorentz force. These conditions require a dose calculation engine capable of taking into consideration the effect of the magnetic field on the dose distribution during the planning stage. Also in the case of a change in anatomy at the time of treatment, a fast online replanning tool is desirable. It is improbable that analytical solutions such as pencil beam calculations can be efficiently adapted for dose calculations within a magnetic field. Monte Carlo simulations have therefore been used for the computations but the calculation speed is generally too slow to allow online replanning. In this work, GPUMCD, a fast graphics processing unit (GPU)-based Monte Carlo dose calculation platform, was benchmarked with a new feature that allows dose calculations within a magnetic field. As a proof of concept, this new feature is validated against experimental measurements. GPUMCD was found to accurately reproduce experimental dose distributions according to a 2%-2 mm gamma analysis in two cases with large magnetic field-induced dose effects: a depth-dose phantom with an air cavity and a lateral-dose phantom surrounded by air. Furthermore, execution times of less than 15 s were achieved for one beam in a prostate case phantom for a 2% statistical uncertainty while less than 20 s were required for a seven-beam plan. These results indicate that GPUMCD is an interesting candidate, being fast and accurate, for dose calculations for the hybrid MRI-Linac modality.

  11. [CUDA-based fast dose calculation in radiotherapy].

    Science.gov (United States)

    Wang, Xianliang; Liu, Cao; Hou, Qing

    2011-10-01

    Dose calculation plays a key role in treatment planning of radiotherapy. Algorithms for dose calculation require high accuracy and computational efficiency. Finite size pencil beam (FSPB) algorithm is a method commonly adopted in the treatment planning system for radiotherapy. However, improvement on its computational efficiency is still desirable for such purpose as real time treatment planning. In this paper, we present an implementation of the FSPB, by which the most time-consuming parts in the algorithm are parallelized and ported on graphic processing unit (GPU). Compared with the FSPB completely running on central processing unit (CPU), the GPU-implemented FSPB can speed up the dose calculation for 25-35 times on a low price GPU (Geforce GT320) and for 55-100 times on a Tesla C1060, indicating that the GPU-implemented FSPB can provide fast enough dose calculations for real-time treatment planning.

  12. Fast spectral source integration in black hole perturbation calculations

    CERN Document Server

    Hopper, Seth; Osburn, Thomas; Evans, Charles R

    2015-01-01

    This paper presents a new technique for achieving spectral accuracy and fast computational performance in a class of black hole perturbation and gravitational self-force calculations involving extreme mass ratios and generic orbits. Called \\emph{spectral source integration} (SSI), this method should see widespread future use in problems that entail (i) point-particle description of the small compact object, (ii) frequency domain decomposition, and (iii) use of the background eccentric geodesic motion. Frequency domain approaches are widely used in both perturbation theory flux-balance calculations and in local gravitational self-force calculations. Recent self-force calculations in Lorenz gauge, using the frequency domain and method of extended homogeneous solutions, have been able to accurately reach eccentricities as high as $e \\simeq 0.7$. We show here SSI successfully applied to Lorenz gauge. In a double precision Lorenz gauge code, SSI enhances the accuracy of results and makes a factor of three improvem...

  13. Parameter analysis calculation on characteristics of portable FAST reactor

    Energy Technology Data Exchange (ETDEWEB)

    Otsubo, Akira; Kowata, Yasuki [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1998-06-01

    In this report, we performed a parameter survey analysis by using the analysis program code STEDFAST (Space, TErrestrial and Deep sea FAST reactor-gas turbine system). Concerning the deep sea fast reactor-gas turbine system, calculations with many variable parameters were performed on the base case of a NaK cooled reactor of 40 kWe. We aimed at total equipment weight and surface area necessary to remove heat from the system as important values of the characteristics of the system. Electric generation power and the material of a pressure hull were specially influential for the weight. The electric generation power, reactor outlet/inlet temperatures, a natural convection heat transfer coefficient of sea water were specially influential for the area. Concerning the space reactor-gas turbine system, the calculations with the variable parameters of compressor inlet temperature, reactor outlet/inlet temperatures and turbine inlet pressure were performed on the base case of a Na cooled reactor of 40 kWe. The first and the second variable parameters were influential for the total equipment weight of the important characteristic of the system. Concerning the terrestrial fast reactor-gas turbine system, the calculations with the variable parameters of heat transferred pipe number in a heat exchanger to produce hot water of 100degC for cogeneration, compressor stage number and the kind of primary coolant material were performed on the base case of a Pb cooled reactor of 100 MWt. In the comparison of calculational results for Pb and Na of primary coolant material, the primary coolant weight flow rate was naturally large for the former case compared with for the latter case because density is very different between them. (J.P.N.)

  14. Fast calculation method of complex space targets' optical cross section.

    Science.gov (United States)

    Han, Yi; Sun, Huayan; Li, Yingchun; Guo, Huichao

    2013-06-10

    This paper utilizes the optical cross section (OCS) to characterize the optical scattering characteristics of a space target under the conditions of Sun lighting. We derive the mathematical expression of OCS according to the radiometric theory, and put forward a fast visualization calculation method of complex space targets' OCS based on an OpenGL and 3D model. Through the OCS simulation of Lambert bodies (cylinder and sphere), the computational accuracy and speed of the algorithm were verified. By using this method, the relative error for OCS will not exceed 0.1%, and it only takes 0.05 s to complete a complex calculation. Additionally, we calculated the OCS of three actual satellites with bidirectional reflectance distribution function model parameters in visible bands, and results indicate that it is easy to distinguish the three targets by comparing their OCS curves. This work is helpful for the identification and classification of unresolved space target based on photometric characteristics.

  15. FastSP: linear time calculation of alignment accuracy.

    Science.gov (United States)

    Mirarab, Siavash; Warnow, Tandy

    2011-12-01

    Multiple sequence alignment is a basic part of much biological research, including phylogeny estimation and protein structure and function prediction. Different alignments on the same set of unaligned sequences are often compared, sometimes in order to assess the accuracy of alignment methods or to infer a consensus alignment from a set of estimated alignments. Three of the standard techniques for comparing alignments, Developer, Modeler and Total Column (TC) scores can be derived through calculations of the set of homologies that the alignments share. However, the brute-force technique for calculating this set is quadratic in the input size. The remaining standard technique, Cline Shift Score, inherently requires quadratic time. In this article, we prove that each of these scores can be computed in linear time, and we present FastSP, a linear-time algorithm for calculating these scores. Even on the largest alignments we explored (one with 50 000 sequences), FastSP completed <2 min and used at most 2 GB of the main memory. The best alternative is qscore, a method whose empirical running time is approximately the same as FastSP when given sufficient memory (at least 8 GB), but whose asymptotic running time has never been theoretically established. In addition, for comparisons of large alignments under lower memory conditions (at most 4 GB of main memory), qscore uses substantial memory (up to 10 GB for the datasets we studied), took more time and failed to analyze the largest datasets. The open-source software and executables are available online at http://www.cs.utexas.edu/~phylo/software/fastsp/. tandy@cs.utexas.edu.

  16. Fast Stiffness Matrix Calculation for Nonlinear Finite Element Method

    Directory of Open Access Journals (Sweden)

    Emir Gülümser

    2014-01-01

    Full Text Available We propose a fast stiffness matrix calculation technique for nonlinear finite element method (FEM. Nonlinear stiffness matrices are constructed using Green-Lagrange strains, which are derived from infinitesimal strains by adding the nonlinear terms discarded from small deformations. We implemented a linear and a nonlinear finite element method with the same material properties to examine the differences between them. We verified our nonlinear formulation with different applications and achieved considerable speedups in solving the system of equations using our nonlinear FEM compared to a state-of-the-art nonlinear FEM.

  17. Fast calculation of HELAS amplitudes using graphics processing unit (GPU)

    CERN Document Server

    Hagiwara, K; Okamura, N; Rainwater, D L; Stelzer, T

    2009-01-01

    We use the graphics processing unit (GPU) for fast calculations of helicity amplitudes of physics processes. As our first attempt, we compute $u\\overline{u}\\to n\\gamma$ ($n=2$ to 8) processes in $pp$ collisions at $\\sqrt{s} = 14$TeV by transferring the MadGraph generated HELAS amplitudes (FORTRAN) into newly developed HEGET ({\\bf H}ELAS {\\bf E}valuation with {\\bf G}PU {\\bf E}nhanced {\\bf T}echnology) codes written in CUDA, a C-platform developed by NVIDIA for general purpose computing on the GPU. Compared with the usual CPU programs, we obtain 40-150 times better performance on the GPU.

  18. Effects of Fast Simple Numerical Calculation Training on Neural Systems.

    Science.gov (United States)

    Takeuchi, Hikaru; Nagase, Tomomi; Taki, Yasuyuki; Sassa, Yuko; Hashizume, Hiroshi; Nouchi, Rui; Kawashima, Ryuta

    2016-01-01

    Cognitive training, including fast simple numerical calculation (FSNC), has been shown to improve performance on untrained processing speed and executive function tasks in the elderly. However, the effects of FSNC training on cognitive functions in the young and on neural mechanisms remain unknown. We investigated the effects of 1-week intensive FSNC training on cognitive function, regional gray matter volume (rGMV), and regional cerebral blood flow at rest (resting rCBF) in healthy young adults. FSNC training was associated with improvements in performance on simple processing speed, speeded executive functioning, and simple and complex arithmetic tasks. FSNC training was associated with a reduction in rGMV and an increase in resting rCBF in the frontopolar areas and a weak but widespread increase in resting rCBF in an anatomical cluster in the posterior region. These results provide direct evidence that FSNC training alone can improve performance on processing speed and executive function tasks as well as plasticity of brain structures and perfusion. Our results also indicate that changes in neural systems in the frontopolar areas may underlie these cognitive improvements.

  19. Generating bit reversed numbers for calculating fast fourier transform

    Digital Repository Service at National Institute of Oceanography (India)

    Suresh, T.

    (6) x (7)). Calculation of FFT becomes a difficult task for computation with input data in natural order and without reordering. Thus an efficient method of reordering is required for FFT calculation. We review a few methods of generating bit... with each successive stage. Other algorithms that depend on the efficient use of swapping data from an array are given in Buneman (1986) Evans (1987) and Walker (1990). Swapping of data is the most widely used method for reordering in FFT calculation. A...

  20. QSL Squasher: A Fast Quasi-separatrix Layer Map Calculator

    Science.gov (United States)

    Tassev, Svetlin; Savcheva, Antonia

    2017-05-01

    Quasi-Separatrix Layers (QSLs) are a useful proxy for the locations where current sheets can develop in the solar corona, and give valuable information about the connectivity in complicated magnetic field configurations. However, calculating QSL maps, even for two-dimensional slices through three-dimensional models of coronal magnetic fields, is a non-trivial task, as it usually involves tracing out millions of magnetic field lines with immense precision. Thus, extending QSL calculations to three dimensions has rarely been done until now. In order to address this challenge, we present QSL Squasher—a public, open-source code, which is optimized for calculating QSL maps in both two and three dimensions on graphics processing units. The code achieves large processing speeds for three reasons, each of which results in an order-of-magnitude speed-up. (1) The code is parallelized using OpenCL. (2) The precision requirements for the QSL calculation are drastically reduced by using perturbation theory. (3) A new boundary detection criterion between quasi-connectivity domains is used, which quickly identifies possible QSL locations that need to be finely sampled by the code. That boundary detection criterion relies on finding the locations of abrupt field-line length changes, which we do by introducing a new Field-line Length Edge (FLEDGE) map. We find FLEDGE maps useful on their own as a quick-and-dirty substitute for QSL maps. QSL Squasher allows construction of high-resolution 3D FLEDGE maps in a matter of minutes, which is two orders of magnitude faster than calculating the corresponding 3D QSL maps. We include a sample of calculations done using QSL Squasher to demonstrate its capabilities as a QSL calculator, as well as to compare QSL and FLEDGE maps.

  1. Fast and Rigorous Assignment Algorithm Multiple Preference and Calculation

    Directory of Open Access Journals (Sweden)

    Ümit Çiftçi

    2010-03-01

    Full Text Available The goal of paper is to develop an algorithm that evaluates students then places them depending on their desired choices according to dependant preferences. The developed algorithm is also used to implement software. The success and accuracy of the software as well as the algorithm are tested by applying it to ability test at Beykent University. This ability test is repeated several times in order to fill all available places at Fine Art Faculty departments in every academic year. It has been shown that this algorithm is very fast and rigorous after application of 2008-2009 and 2009-20010 academic years.Key Words: Assignment algorithm, student placement, ability test

  2. QSL Squasher: A Fast Quasi-Separatrix Layer Map Calculator

    CERN Document Server

    Tassev, Svetlin

    2016-01-01

    Quasi-Separatrix Layers (QSLs) are a useful proxy for the locations where current sheets can develop in the solar corona, and give valuable information about the connectivity in complicated magnetic field configurations. However, calculating QSL maps even for 2-dimensional slices through 3-dimensional models of coronal magnetic fields is a non-trivial task as it usually involves tracing out millions of magnetic field lines with immense precision. Thus, extending QSL calculations to three dimensions has rarely been done until now. In order to address this challenge, we present QSL Squasher -- a public, open-source code, which is optimized for calculating QSL maps in both two and three dimensions on GPUs. The code achieves large processing speeds for three reasons, each of which results in an order-of-magnitude speed-up. 1) The code is parallelized using OpenCL. 2) The precision requirements for the QSL calculation are drastically reduced by using perturbation theory. 3) A new boundary detection criterion betwe...

  3. Calculation of dosimetry parameters for fast neutron radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Wells, A.H.

    1978-05-01

    A computer simulation of the interactions of 50 MeV d/sup +/ on Be and 42 MeV p/sup +/ on Be neutron spectra with ICRU muscle tissue and Shonka A-150 tissue equivalent plastic was performed to allow computation of the charged particle spectra that result. Nuclear data were obtained from the Evaluated Nuclear Data File (ENDF) whenever possible and from the Intranuclear Cascade and Evaporation models otherwise. The dosimetry parameters calculated are: the kerma ratio, K/sub A-150//K/sub tissue/; the energy required to form an ion pair, W; and the stopping power ratio, S/sub g//sup W/.

  4. Improved method of generating bit reversed numbers for calculating fast fourier transform

    Digital Repository Service at National Institute of Oceanography (India)

    Suresh, T.

    Fast Fourier Transform (FFT) is an important tool required for signal processing in defence applications. This paper reports an improved method for generating bit reversed numbers needed in calculating FFT using radix-2. The refined algorithm takes...

  5. Fast calculation of digitally reconstructed radiographs using light fields

    Science.gov (United States)

    Russakoff, Daniel B.; Rohlfing, Torsten; Rueckert, Daniel; Shahidi, Ramin; Kim, Daniel; Maurer, Calvin R., Jr.

    2003-05-01

    Calculating digitally reconstructed radiographs (DRRs)is an important step in intensity-based fluoroscopy-to-CT image registration methods. Unfortunately, the standard techniques to generate DRRs involve ray casting and run in time O(n3),where we assume that n is approximately the size (in voxels) of one side of the DRR as well as one side of the CT volume. Because of this, generation of DRRs is typically the rate-limiting step in the execution time of intensity-based fluoroscopy-to-CT registration algorithms. We address this issue by extending light field rendering techniques from the computer graphics community to generate DRRs instead of conventional rendered images. Using light fields allows most of the computation to be performed in a preprocessing step;after this precomputation step, very accurate DRRs can be generated in time O(n2). Using a light field generated from 1,024 DRRs of resolution 256×256, we can create new DRRs that appear visually identical to ones generated by conventional ray casting. Importantly, the DRRs generated using the light field are computed over 300 times faster than DRRs generated using conventional ray casting(50 vs.17,000 ms on a PC with a 2 GHz Intel Pentium 4 processor).

  6. System of Modelling and Calculation Analysis of Neutron- Physical Experiments at Fast Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Moiseyev, A.V. [SSC RF - IPPE, 1 Bondarenko Square, Obninsk, Kaluga Region 249033 (Russian Federation)

    2008-07-01

    There is an actual task on storage, processing and analysis of the unique experimental data received on power fast reactors for their subsequent use in projects of fast reactors of new (4.) generation. For modeling and carrying out analysis of experiments the integrated computing system MODEXSYS has been developed. In this system the mechanism for consecutive calculation of a fast reactor states with the detailed description of its components is created. The system includes the database describing fast reactor states, results of neutron-physical characteristics measurements at fast reactor, calculation and benchmark models of experiments and calculation results. In system convenient search means and the special graphics shell are provided. It has Interfaces for processing of calculation results and their analysis. MODEXSYS system has been applied for analysis of three types of experiments at fast reactor: k{sub eff}, control rod worth and energy release distribution. The most important results of this analysis are described. Application of MODEXSYS system will raise accuracy and reliability of forecasting of fast reactors neutron-physical characteristics; for BN-600 reactor recommended level of accuracy is resulted. (authors)

  7. Fast calculation method of computer-generated cylindrical hologram using wave-front recording surface.

    Science.gov (United States)

    Zhao, Yu; Piao, Mei-lan; Li, Gang; Kim, Nam

    2015-07-01

    Fast calculation method for a computer-generated cylindrical hologram (CGCH) is proposed. The method consists of two steps: the first step is a calculation of a virtual wave-front recording surface (WRS), which is located between the 3D object and CGCH. In the second step, in order to obtain a CGCH, we execute the diffraction calculation based on the fast Fourier transform (FFT) from the WRS to the CGCH, which are in the same concentric arrangement. The computational complexity is dramatically reduced in comparison with direct integration method. The simulation results confirm that our proposed method is able to improve the computational speed of CGCH.

  8. Simple and fast cosine approximation method for computer-generated hologram calculation.

    Science.gov (United States)

    Nishitsuji, Takashi; Shimobaba, Tomoyoshi; Kakue, Takashi; Arai, Daisuke; Ito, Tomoyoshi

    2015-12-14

    The cosine function is a heavy computational operation in computer-generated hologram (CGH) calculation; therefore, it is implemented by substitution methods such as a look-up table. However, the computational load and required memory space of such methods are still large. In this study, we propose a simple and fast cosine function approximation method for CGH calculation. As a result, we succeeded in creating CGH with sufficient quality and made the calculation time 1.6 times as fast at maximum compared to using the look-up table of the cosine function on CPU implementation.

  9. FAST-PT: a novel algorithm to calculate convolution integrals in cosmological perturbation theory

    Science.gov (United States)

    McEwen, Joseph E.; Fang, Xiao; Hirata, Christopher M.; Blazek, Jonathan A.

    2016-09-01

    We present a novel algorithm, FAST-PT, for performing convolution or mode-coupling integrals that appear in nonlinear cosmological perturbation theory. The algorithm uses several properties of gravitational structure formation—the locality of the dark matter equations and the scale invariance of the problem—as well as Fast Fourier Transforms to describe the input power spectrum as a superposition of power laws. This yields extremely fast performance, enabling mode-coupling integral computations fast enough to embed in Monte Carlo Markov Chain parameter estimation. We describe the algorithm and demonstrate its application to calculating nonlinear corrections to the matter power spectrum, including one-loop standard perturbation theory and the renormalization group approach. We also describe our public code (in Python) to implement this algorithm. The code, along with a user manual and example implementations, is available at https://github.com/JoeMcEwen/FAST-PT.

  10. Non-uniform sampled scalar diffraction calculation using non-uniform fast Fourier transform

    CERN Document Server

    Shimobaba, Tomoyoshi; Oikawa, Minoru; Okada, Naohisa; Endo, Yutaka; Hirayama, Ryuji; Ito, Tomoyoshi

    2013-01-01

    Scalar diffraction calculations such as the angular spectrum method (ASM) and Fresnel diffraction, are widely used in the research fields of optics, X-rays, electron beams, and ultrasonics. It is possible to accelerate the calculation using fast Fourier transform (FFT); unfortunately, acceleration of the calculation of non-uniform sampled planes is limited due to the property of the FFT that imposes uniform sampling. In addition, it gives rise to wasteful sampling data if we calculate a plane having locally low and high spatial frequencies. In this paper, we developed non-uniform sampled ASM and Fresnel diffraction to improve the problem using the non-uniform FFT.

  11. Fast and accurate calculation of dilute quantum gas using Uehling-Uhlenbeck model equation

    Science.gov (United States)

    Yano, Ryosuke

    2017-02-01

    The Uehling-Uhlenbeck (U-U) model equation is studied for the fast and accurate calculation of a dilute quantum gas. In particular, the direct simulation Monte Carlo (DSMC) method is used to solve the U-U model equation. DSMC analysis based on the U-U model equation is expected to enable the thermalization to be accurately obtained using a small number of sample particles and the dilute quantum gas dynamics to be calculated in a practical time. Finally, the applicability of DSMC analysis based on the U-U model equation to the fast and accurate calculation of a dilute quantum gas is confirmed by calculating the viscosity coefficient of a Bose gas on the basis of the Green-Kubo expression and the shock layer of a dilute Bose gas around a cylinder.

  12. Calculated power distribution of a thermionic, beryllium oxide reflected, fast-spectrum reactor

    Science.gov (United States)

    Mayo, W.; Lantz, E.

    1973-01-01

    A procedure is developed and used to calculate the detailed power distribution in the fuel elements next to a beryllium oxide reflector of a fast-spectrum, thermionic reactor. The results of the calculations show that, although the average power density in these outer fuel elements is not far from the core average, the power density at the very edge of the fuel closest to the beryllium oxide is about 1.8 times the core avearge.

  13. Monte Carlo Calculations for Neutron and Gamma Radiation Fields on a Fast Neutron Irradiation Device

    Science.gov (United States)

    Vieira, A.; Ramalho, A.; Gonçalves, I. C.; Fernandes, A.; Barradas, N.; Marques, J. G.; Prata, J.; Chaussy, Ch.

    We used the Monte Carlo program MCNP to calculate the neutron and gamma fluxes on a fast neutron irradiation facility being installed on the Portuguese Research Reactor (RPI). The purpose of this facility is to provide a fast neutron beam for irradiation of electronic circuits. The gamma dose should be minimized. This is achieved by placing a lead shield preceded by a thin layer of boral. A fast neutron flux of the order of 109 n/cm2s is expected at the exit of the tube, while the gamma radiation is kept below 20 Gy/h. We will present results of the neutron and gamma doses for several locations along the tube and different thickness of the lead shield. We found that the neutron beam is very collimated at the end of the tube with a dominant component on the fast region.

  14. FAST-PT: a novel algorithm to calculate convolution integrals in cosmological perturbation theory

    CERN Document Server

    McEwen, Joseph E; Hirata, Christopher M; Blazek, Jonathan A

    2016-01-01

    We present a novel algorithm, FAST-PT, for performing convolution or mode-coupling integrals that appear in nonlinear cosmological perturbation theory. The algorithm uses several properties of gravitational structure formation -- the locality of the dark matter equations and the scale invariance of the problem -- as well as Fast Fourier Transforms to describe the input power spectrum as a superposition of power laws. This yields extremely fast performance, enabling mode-coupling integral computations fast enough to embed in Monte Carlo Markov Chain parameter estimation. We describe the algorithm and demonstrate its application to calculating nonlinear corrections to the matter power spectrum, including one-loop standard perturbation theory and the renormalization group approach. We also describe our public code (in Python) to implement this algorithm, including the applications described here.

  15. Neutronic calculation of fast reactors by the EUCLID/V1 integrated code

    Science.gov (United States)

    Koltashev, D. A.; Stakhanova, A. A.

    2017-01-01

    This article considers neutronic calculation of a fast-neutron lead-cooled reactor BREST-OD-300 by the EUCLID/V1 integrated code. The main goal of development and application of integrated codes is a nuclear power plant safety justification. EUCLID/V1 is integrated code designed for coupled neutronics, thermomechanical and thermohydraulic fast reactor calculations under normal and abnormal operating conditions. EUCLID/V1 code is being developed in the Nuclear Safety Institute of the Russian Academy of Sciences. The integrated code has a modular structure and consists of three main modules: thermohydraulic module HYDRA-IBRAE/LM/V1, thermomechanical module BERKUT and neutronic module DN3D. In addition, the integrated code includes databases with fuel, coolant and structural materials properties. Neutronic module DN3D provides full-scale simulation of neutronic processes in fast reactors. Heat sources distribution, control rods movement, reactivity level changes and other processes can be simulated. Neutron transport equation in multigroup diffusion approximation is solved. This paper contains some calculations implemented as a part of EUCLID/V1 code validation. A fast-neutron lead-cooled reactor BREST-OD-300 transient simulation (fuel assembly floating, decompression of passive feedback system channel) and cross-validation with MCU-FR code results are presented in this paper. The calculations demonstrate EUCLID/V1 code application for BREST-OD-300 simulating and safety justification.

  16. A fast high-order method to calculate wakefield forces in an electron beam

    CERN Document Server

    Qiang, Ji; Ryne, Robert D

    2012-01-01

    In this paper we report on a high-order fast method to numerically calculate wakefield forces in an electron beam given a wake function model. This method is based on a Newton-Cotes quadrature rule for integral approximation and an FFT method for discrete summation that results in an $O(Nlog(N))$ computational cost, where $N$ is the number of grid points. Using the Simpson quadrature rule with an accuracy of $O(h^4)$, where $h$ is the grid size, we present numerical calculation of the wakefields from a resonator wake function model and from a one-dimensional coherent synchrotron radiation (CSR) wake model. Besides the fast speed and high numerical accuracy, the calculation using the direct line density instead of the first derivative of the line density avoids numerical filtering of the electron density function for computing the CSR wakefield force.

  17. Fast calculation of two-electron-repulsion integrals: a numerical approach

    CERN Document Server

    Lopes, Pedro E M

    2016-01-01

    An alternative methodology to evaluate two-electron-repulsion integrals based on numerical approximation is proposed. Computational chemistry has branched into two major fields with methodologies based on quantum mechanics and classical force fields. However, there are significant shadowy areas not covered by any of the available methods. Many relevant systems are often too big for traditional quantum chemical methods while being chemically too complex for classical force fields. Examples include systems in nanomedicine, studies of metalloproteins, etc. There is an urgent need to develop fast quantum chemical methods able to study large and complex systems. This work is a proof-of-concept on the numerical techniques required to develop accurate and computationally efficient algorithms for the fast calculation of electron-repulsion integrals, one of the most significant bottlenecks in the extension of quantum chemistry to large systems. All concepts and calculations were developed for the three-center integral...

  18. SIML: a fast SIMD algorithm for calculating LINGO chemical similarities on GPUs and CPUs.

    Science.gov (United States)

    Haque, Imran S; Pande, Vijay S; Walters, W Patrick

    2010-04-26

    LINGOs are a holographic measure of chemical similarity based on text comparison of SMILES strings. We present a new algorithm for calculating LINGO similarities amenable to parallelization on SIMD architectures (such as GPUs and vector units of modern CPUs). We show that it is nearly 3x as fast as existing algorithms on a CPU, and over 80x faster than existing methods when run on a GPU.

  19. A Fast and Scalable Algorithm for Calculating the Achievable Capacity of a Wireless Mesh Network

    Science.gov (United States)

    2016-05-09

    Garg and J. Koenemann, “Faster and simpler algorithms for multi- commodity flow and other fractional packing problems,” SIAM Journal on Computing, vol...A Fast and Scalable Algorithm for Calculating the Achievable Capacity of a Wireless Mesh Network Greg Kuperman, Jun Sun, Nathaniel M. Jones, and... algorithm to rapidly determine the maximum concurrent flow for an arbitrary number of unicast and multicast connections subject to arbitrary binary

  20. Fast Near-Field Calculation for Volume Integral Equations for Layered Media

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.; Meincke, Peter; Breinbjerg, Olav

    2005-01-01

    An efficient technique based on the Fast Fourier Transform (FFT) for calculating near-field scattering by dielectric objects in layered media is presented. A higher or-der method of moments technique is employed to solve the volume integral equation for the unknown induced volume current density....... Afterwards, the scattered electric field can be easily computed at a regular rectangular grid on any horizontal plane us-ing a 2-dimensional FFT. This approach provides significant speedup in the near-field calculation in comparison to a straightforward numerical evaluation of the ra-diation integral since...

  1. Fast calculation of spherical computer generated hologram using spherical wave spectrum method.

    Science.gov (United States)

    Jackin, Boaz Jessie; Yatagai, Toyohiko

    2013-01-14

    A fast calculation method for computer generation of spherical holograms in proposed. This method is based on wave propagation defined in spectral domain and in spherical coordinates. The spherical wave spectrum and transfer function were derived from boundary value solutions to the scalar wave equation. It is a spectral propagation formula analogous to angular spectrum formula in cartesian coordinates. A numerical method to evaluate the derived formula is suggested, which uses only N(logN)2 operations for calculations on N sampling points. Simulation results are presented to verify the correctness of the proposed method. A spherical hologram for a spherical object was generated and reconstructed successfully using the proposed method.

  2. Calculation of the ionization differential effective cross sections in fast ion-atom collisions

    CERN Document Server

    Kaminskij, A K

    2002-01-01

    The method of the calculations of the ionization effective cross sections d sigma/d OMEGA differential in the incident ion scattering angle is described in fast collisions of light ions and atoms. The calculated values of angular distributions of the ions Al, Mg (for the different values of charge and energy of ions) after their collisions with the Ne, Mg atoms being ionized are reported. The dependence of such angular distributions on the incident ion charge and energy and the initial state of ejected electron is investigated

  3. Test case specifications for coupled neutronics-thermal hydraulics calculation of Gas-cooled Fast Reactor

    Science.gov (United States)

    Osuský, F.; Bahdanovich, R.; Farkas, G.; Haščík, J.; Tikhomirov, G. V.

    2017-01-01

    The paper is focused on development of the coupled neutronics-thermal hydraulics model for the Gas-cooled Fast Reactor. It is necessary to carefully investigate coupled calculations of new concepts to avoid recriticality scenarios, as it is not possible to ensure sub-critical state for a fast reactor core under core disruptive accident conditions. Above mentioned calculations are also very suitable for development of new passive or inherent safety systems that can mitigate the occurrence of the recriticality scenarios. In the paper, the most promising fuel material compositions together with a geometry model are described for the Gas-cooled fast reactor. Seven fuel pin and fuel assembly geometry is proposed as a test case for coupled calculation with three different enrichments of fissile material in the form of Pu-UC. The reflective boundary condition is used in radial directions of the test case and vacuum boundary condition is used in axial directions. During these condition, the nuclear system is in super-critical state and to achieve a stable state (which is numerical representation of operational conditions) it is necessary to decrease the reactivity of the system. The iteration scheme is proposed, where SCALE code system is used for collapsing of a macroscopic cross-section into few group representation as input for coupled code NESTLE.

  4. Transient coupled calculations of the Molten Salt Fast Reactor using the Transient Fission Matrix approach

    Energy Technology Data Exchange (ETDEWEB)

    Laureau, A., E-mail: laureau.axel@gmail.com; Heuer, D.; Merle-Lucotte, E.; Rubiolo, P.R.; Allibert, M.; Aufiero, M.

    2017-05-15

    Highlights: • Neutronic ‘Transient Fission Matrix’ approach coupled to the CFD OpenFOAM code. • Fission Matrix interpolation model for fast spectrum homogeneous reactors. • Application for coupled calculations of the Molten Salt Fast Reactor. • Load following, over-cooling and reactivity insertion transient studies. • Validation of the reactor intrinsic stability for normal and accidental transients. - Abstract: In this paper we present transient studies of the Molten Salt Fast Reactor (MSFR). This generation IV reactor is characterized by a liquid fuel circulating in the core cavity, requiring specific simulation tools. An innovative neutronic approach called “Transient Fission Matrix” is used to perform spatial kinetic calculations with a reduced computational cost through a pre-calculation of the Monte Carlo spatial and temporal response of the system. Coupled to this neutronic approach, the Computational Fluid Dynamics code OpenFOAM is used to model the complex flow pattern in the core. An accurate interpolation model developed to take into account the thermal hydraulics feedback on the neutronics including reactivity and neutron flux variation is presented. Finally different transient studies of the reactor in normal and accidental operating conditions are detailed such as reactivity insertion and load following capacities. The results of these studies illustrate the excellent behavior of the MSFR during such transients.

  5. Theoretical study and calculation of the response of a fast neutron dosemeter based on track detection

    Energy Technology Data Exchange (ETDEWEB)

    Decossas, J.L.; Vareille, J.C.; Moliton, J.P.; Teyssier, J.L. (Limoges Univ., 87 (France). Lab. d' Electronique des Polymeres sous Faisceaux Ioniques)

    1983-01-01

    A fast neutron dosemeter is generally composed of a radiator in which n-p elastic scattering occurs and a detector which registers protons. A theoretical study, and the calculation (FORTRAN program) of the response of such a dosemeter is presented involving two steps: 1) The proton flux emerging from a thick radiator on which monoenergetic neutrons are normally incident is studied. This is characterised by its energy spectrum depending on the neutron energy and on the radiator thickness. 2) Proton detection being achieved with a solid state nuclear track detector whose performance is known, the number of registered tracks are calculated. The dosemeter sensitivity (tracks cm/sup -2/. Sv/sup -1/) is deduced. Then, the calculations show that it is possible to optimise the radiator thickness to obtain the smallest variation in sensitivity with neutron energy. The theoretical results are in good agreement with the experimental ones found in the literature.

  6. Method of Images for the Fast Calculation of Temperature Distributions in Packaged VLSI Chips

    CERN Document Server

    Hériz, Virginia Martín; Kemper, T; Kang, S -M; Shakouri, A

    2008-01-01

    Thermal aware routing and placement algorithms are important in industry. Currently, there are reasonably fast Green's function based algorithms that calculate the temperature distribution in a chip made from a stack of different materials. However, the layers are all assumed to have the same size, thus neglecting the important fact that the thermal mounts which are placed underneath the chip can be significantly larger than the chip itself. In an earlier publication, we showed that the image blurring technique can be used to calculate quickly temperature distribution in realistic packages. For this method to be effective, temperature distribution for several point heat sources at the center and at the corner and edges of the chip should be calculated using finite element analysis (FEA) or measured. In addition, more accurate results require correction by a weighting function that will need several FEA simulations. In this paper, we introduce the method of images that take the symmetry of the thermal boundary...

  7. GPU-based ultra fast dose calculation using a finite pencil beam model

    CERN Document Server

    Gu, Xuejun; Men, Chunhua; Pan, Hubert; Majumdar, Amitava; Jiang, Steve B

    2009-01-01

    Online adaptive radiation therapy (ART) is an attractive concept that promises the ability to deliver an optimal treatment in response to the inter-fraction variability in patient anatomy. However, it has yet to be realized due to technical limitations. Fast dose deposit coefficient calculation is a critical component of the online planning process that is required for plan optimization of intensity modulated radiation therapy (IMRT). Computer graphics processing units (GPUs) are well-suited to provide the requisite fast performance for the data-parallel nature of dose calculation. In this work, we develop a dose calculation engine based on a finite-size pencil beam (FSPB) algorithm and a GPU parallel computing framework. The developed framework can accommodate any FSPB model. We test our implementation on a case of a water phantom and a case of a prostate cancer patient with varying beamlet and voxel sizes. All testing scenarios achieved speedup ranging from 200~400 times when using a NVIDIA Tesla C1060 card...

  8. Fast calculation of computer-generated hologram using run-length encoding based recurrence relation.

    Science.gov (United States)

    Nishitsuji, Takashi; Shimobaba, Tomoyoshi; Kakue, Takashi; Ito, Tomoyoshi

    2015-04-20

    Computer-Generated Holograms (CGHs) can be generated by superimposing zoneplates. A zoneplate is a grating that can concentrate an incident light into a point. Since a zoneplate has a circular symmetry, we reported an algorithm that rapidly generates a zoneplate by drawing concentric circles using computer graphic techniques. However, random memory access was required in the algorithm and resulted in degradation of the computational efficiency. In this study, we propose a fast CGH generation algorithm without random memory access using run-length encoding (RLE) based recurrence relation. As a result, we succeeded in improving the calculation time by 88%, compared with that of the previous work.

  9. Highly Parallel Demagnetization Field Calculation Using the Fast Multipole Method on Tetrahedral Meshes with Continuous Sources

    CERN Document Server

    Palmesi, Pietro; Bruckner, Florian; Abert, Claas; Suess, Dieter

    2016-01-01

    The long-range magnetic field is the most time-consuming part in micromagnetic simulations. Improvements both on a numerical and computational basis can relief problems related to this bottleneck. This work presents an efficient implementation of the Fast Multipole Method [FMM] for the magnetic scalar potential as used in micromagnetics. We assume linearly magnetized tetrahedral sources, treat the near field directly and use analytical integration on the multipole expansion in the far field. This approach tackles important issues like the vectorial and continuous nature of the magnetic field. By using FMM the calculations scale linearly in time and memory.

  10. Extension and evaluation of the multilevel summation method for fast long-range electrostatics calculations.

    Science.gov (United States)

    Moore, Stan G; Crozier, Paul S

    2014-06-21

    Several extensions and improvements have been made to the multilevel summation method (MSM) of computing long-range electrostatic interactions. These include pressure calculation, an improved error estimator, faster direct part calculation, extension to non-orthogonal (triclinic) systems, and parallelization using the domain decomposition method. MSM also allows fully non-periodic long-range electrostatics calculations which are not possible using traditional Ewald-based methods. In spite of these significant improvements to the MSM algorithm, the particle-particle particle-mesh (PPPM) method was still found to be faster for the periodic systems we tested on a single processor. However, the fast Fourier transforms (FFTs) that PPPM relies on represent a major scaling bottleneck for the method when running on many cores (because the many-to-many communication pattern of the FFT becomes expensive) and MSM scales better than PPPM when using a large core count for two test problems on Sandia's Redsky machine. This FFT bottleneck can be reduced by running PPPM on only a subset of the total processors. MSM is most competitive for relatively low accuracy calculations. On Sandia's Chama machine, however, PPPM is found to scale better than MSM for all core counts that we tested. These results suggest that PPPM is usually more efficient than MSM for typical problems running on current high performance computers. However, further improvements to MSM algorithm could increase its competitiveness for calculation of long-range electrostatic interactions.

  11. Fast and accurate calculations for cumulative first-passage time distributions in Wiener diffusion models

    DEFF Research Database (Denmark)

    Blurton, Steven Paul; Kesselmeier, M.; Gondan, Matthias

    2012-01-01

    related work on the density of first-passage times [Navarro, D.J., Fuss, I.G. (2009). Fast and accurate calculations for first-passage times in Wiener diffusion models. Journal of Mathematical Psychology, 53, 222-230]. Two representations exist for the distribution, both including infinite series. We......We propose an improved method for calculating the cumulative first-passage time distribution in Wiener diffusion models with two absorbing barriers. This distribution function is frequently used to describe responses and error probabilities in choice reaction time tasks. The present work extends...... derive upper bounds for the approximation error resulting from finite truncation of the series, and we determine the number of iterations required to limit the error below a pre-specified tolerance. For a given set of parameters, the representation can then be chosen which requires the least...

  12. Impact of nuclear data on sodium-cooled fast reactor calculations

    Science.gov (United States)

    Aures, Alexander; Bostelmann, Friederike; Zwermann, Winfried; Velkov, Kiril

    2016-03-01

    Neutron transport and depletion calculations are performed in combination with various nuclear data libraries in order to assess the impact of nuclear data on safety-relevant parameters of sodium-cooled fast reactors. These calculations are supplemented by systematic uncertainty analyses with respect to nuclear data. Analysed quantities are the multiplication factor and nuclide densities as a function of burn-up and the Doppler and Na-void reactivity coefficients at begin of cycle. While ENDF/B-VII.0 / -VII.1 yield rather consistent results, larger discrepancies are observed between the JEFF libraries. While the newest evaluation, JEFF-3.2, agrees with the ENDF/B-VII libraries, the JEFF-3.1.2 library yields significant larger multiplication factors.

  13. Impact of nuclear data on sodium-cooled fast reactor calculations

    Directory of Open Access Journals (Sweden)

    Aures Alexander

    2016-01-01

    Full Text Available Neutron transport and depletion calculations are performed in combination with various nuclear data libraries in order to assess the impact of nuclear data on safety-relevant parameters of sodium-cooled fast reactors. These calculations are supplemented by systematic uncertainty analyses with respect to nuclear data. Analysed quantities are the multiplication factor and nuclide densities as a function of burn-up and the Doppler and Na-void reactivity coefficients at begin of cycle. While ENDF/B-VII.0 / -VII.1 yield rather consistent results, larger discrepancies are observed between the JEFF libraries. While the newest evaluation, JEFF-3.2, agrees with the ENDF/B-VII libraries, the JEFF-3.1.2 library yields significant larger multiplication factors.

  14. GPU-based fast Monte Carlo dose calculation for proton therapy.

    Science.gov (United States)

    Jia, Xun; Schümann, Jan; Paganetti, Harald; Jiang, Steve B

    2012-12-07

    Accurate radiation dose calculation is essential for successful proton radiotherapy. Monte Carlo (MC) simulation is considered to be the most accurate method. However, the long computation time limits it from routine clinical applications. Recently, graphics processing units (GPUs) have been widely used to accelerate computationally intensive tasks in radiotherapy. We have developed a fast MC dose calculation package, gPMC, for proton dose calculation on a GPU. In gPMC, proton transport is modeled by the class II condensed history simulation scheme with a continuous slowing down approximation. Ionization, elastic and inelastic proton nucleus interactions are considered. Energy straggling and multiple scattering are modeled. Secondary electrons are not transported and their energies are locally deposited. After an inelastic nuclear interaction event, a variety of products are generated using an empirical model. Among them, charged nuclear fragments are terminated with energy locally deposited. Secondary protons are stored in a stack and transported after finishing transport of the primary protons, while secondary neutral particles are neglected. gPMC is implemented on the GPU under the CUDA platform. We have validated gPMC using the TOPAS/Geant4 MC code as the gold standard. For various cases including homogeneous and inhomogeneous phantoms as well as a patient case, good agreements between gPMC and TOPAS/Geant4 are observed. The gamma passing rate for the 2%/2 mm criterion is over 98.7% in the region with dose greater than 10% maximum dose in all cases, excluding low-density air regions. With gPMC it takes only 6-22 s to simulate 10 million source protons to achieve ∼1% relative statistical uncertainty, depending on the phantoms and energy. This is an extremely high efficiency compared to the computational time of tens of CPU hours for TOPAS/Geant4. Our fast GPU-based code can thus facilitate the routine use of MC dose calculation in proton therapy.

  15. Ablation experiment and threshold calculation of titanium alloy irradiated by ultra-fast pulse laser

    Directory of Open Access Journals (Sweden)

    Buxiang Zheng

    2014-02-01

    Full Text Available The interaction between an ultra-fast pulse laser and a material's surface has become a research hotspot in recent years. Micromachining of titanium alloy with an ultra-fast pulse laser is a very important research direction, and it has very important theoretical significance and application value in investigating the ablation threshold of titanium alloy irradiated by ultra-fast pulse lasers. Irradiated by a picosecond pulse laser with wavelengths of 1064 nm and 532 nm, the surface morphology and feature sizes, including ablation crater width (i.e. diameter, ablation depth, ablation area, ablation volume, single pulse ablation rate, and so forth, of the titanium alloy were studied, and their ablation distributions were obtained. The experimental results show that titanium alloy irradiated by a picosecond pulse infrared laser with a 1064 nm wavelength has better ablation morphology than that of the green picosecond pulse laser with a 532 nm wavelength. The feature sizes are approximately linearly dependent on the laser pulse energy density at low energy density and the monotonic increase in laser pulse energy density. With the increase in energy density, the ablation feature sizes are increased. The rate of increase in the feature sizes slows down gradually once the energy density reaches a certain value, and gradually saturated trends occur at a relatively high energy density. Based on the linear relation between the laser pulse energy density and the crater area of the titanium alloy surface, and the Gaussian distribution of the laser intensity on the cross section, the ablation threshold of titanium alloy irradiated by an ultra-fast pulse laser was calculated to be about 0.109 J/cm2.

  16. Calculation of fusion gain in fast ignition with magnetic target by relativistic electrons and protons

    Directory of Open Access Journals (Sweden)

    A Parvazian

    2010-12-01

    Full Text Available Fast ignition is a new method for inertial confinement fusion (ICF in which the compression and ignition steps are separated. In the first stage, fuel is compressed by laser or ion beams. In the second phase, relativistic electrons are generated by pettawat laser in the fuel. Also, in the second phase 5-35 MeV protons can be generated in the fuel. Electrons or protons can penetrate in to the ultra-dense fuel and deposit their energy in the fuel . More recently, cylindrical rather than spherical fuel chambers with magnetic control in the plasma domain have been also considered. This is called magnetized target fusion (MTF. Magnetic field has effects on relativistic electrons energy deposition rate in fuel. In this work, fast ignition method in cylindrical fuel chambers is investigated and transportation of the relativistic electrons and protons is calculated using MCNPX and FLUKA codes with 0. 25 and 0. 5 tesla magnetic field in single and dual hot spot. Furthermore, the transfer rate of relativistic electrons and high energy protons to the fuel and fusion gain are calculated. The results show that the presence of external magnetic field guarantees higher fusion gain, and relativistic electrons are much more appropriate objects for ignition. MTF in dual hot spot can be considered as an appropriate substitution for the current ICF techniques.

  17. Fast Monte Carlo Simulation for Patient-specific CT/CBCT Imaging Dose Calculation

    CERN Document Server

    Jia, Xun; Gu, Xuejun; Jiang, Steve B

    2011-01-01

    Recently, X-ray imaging dose from computed tomography (CT) or cone beam CT (CBCT) scans has become a serious concern. Patient-specific imaging dose calculation has been proposed for the purpose of dose management. While Monte Carlo (MC) dose calculation can be quite accurate for this purpose, it suffers from low computational efficiency. In response to this problem, we have successfully developed a MC dose calculation package, gCTD, on GPU architecture under the NVIDIA CUDA platform for fast and accurate estimation of the x-ray imaging dose received by a patient during a CT or CBCT scan. Techniques have been developed particularly for the GPU architecture to achieve high computational efficiency. Dose calculations using CBCT scanning geometry in a homogeneous water phantom and a heterogeneous Zubal head phantom have shown good agreement between gCTD and EGSnrc, indicating the accuracy of our code. In terms of improved efficiency, it is found that gCTD attains a speed-up of ~400 times in the homogeneous water ...

  18. A fast calculating two-stream-like multiple scattering algorithm that captures azimuthal and elevation variations

    Science.gov (United States)

    Fiorino, Steven T.; Elmore, Brannon; Schmidt, Jaclyn; Matchefts, Elizabeth; Burley, Jarred L.

    2016-05-01

    Properly accounting for multiple scattering effects can have important implications for remote sensing and possibly directed energy applications. For example, increasing path radiance can affect signal noise. This study describes the implementation of a fast-calculating two-stream-like multiple scattering algorithm that captures azimuthal and elevation variations into the Laser Environmental Effects Definition and Reference (LEEDR) atmospheric characterization and radiative transfer code. The multiple scattering algorithm fully solves for molecular, aerosol, cloud, and precipitation single-scatter layer effects with a Mie algorithm at every calculation point/layer rather than an interpolated value from a pre-calculated look-up-table. This top-down cumulative diffusivity method first considers the incident solar radiance contribution to a given layer accounting for solid angle and elevation, and it then measures the contribution of diffused energy from previous layers based on the transmission of the current level to produce a cumulative radiance that is reflected from a surface and measured at the aperture at the observer. Then a unique set of asymmetry and backscattering phase function parameter calculations are made which account for the radiance loss due to the molecular and aerosol constituent reflectivity within a level and allows for a more accurate characterization of diffuse layers that contribute to multiple scattered radiances in inhomogeneous atmospheres. The code logic is valid for spectral bands between 200 nm and radio wavelengths, and the accuracy is demonstrated by comparing the results from LEEDR to observed sky radiance data.

  19. A Fast Time-Delay Calculation Method in Through-Wall-Radar Detection Scenario

    Directory of Open Access Journals (Sweden)

    Zhang Qi

    2016-01-01

    Full Text Available In TWR (Through Wall Radar signal processing procedure, time delay estimation is one of the key steps in target localization and high resolution imaging. In time domain imaging procedure such as back projection imaging algorithm, round trip propagation time delay at the path of “transmitter-target-receiver” needs to be calculated for each pixel in imaging region. In typical TWR scenario, transmitter and receiver are at one side and targets at the other side of a wall. Based on two-dimensional searching algorithm or solving two variables equation of four times, traditional time delay calculation algorithms are complex and time consuming, and cannot be used to real-time imaging procedure. In this paper, a new fast time-delay (FTD algorithm is presented. Because of that incident angle at one side equals to refracting angle at the other side, an equation of lateral distance through the wall can be established. By solving this equation, the lateral distance can be obtained and total propagation time delay can be calculated subsequently. Through processing simulation data, the result shows that new algorithm can be applied effectively to real-time time-delay calculation in TWR signal processing.

  20. Development of a PYTHON-based emittance calculator at Fermilab Accelerator Science and Technology (FAST) facility

    Science.gov (United States)

    Green, A. T.

    Beam emittance is an important characteristic describing charged particle beams. In linear accelerators (linac), it is critical to characterize the beam phase space parameters and, in particular, to precisely measure transverse beam emittance. The quadrupole scan (quad-scan) is a well-established technique used to characterize transverse beam parameters in four-dimensional phase space, including beam emittance. A computational algorithm with PYTHON scripts has been developed to estimate beam parameters, in particular beam emittance, using the quad-scan technique in the electron linac at the Fermilab Accelerator Science and Technology (FAST) facility. This script has been implemented in conjunction with an automated quad-scan tool (also written in PYTHON) and has decreased the time it takes to perform a single quad-scan from an hour to a few minutes. From the experimental data, the emittance calculator quickly delivers several results including: geometrical and normalized transverse emittance, Courant-Snyder parameters, and plots of the beam size versus quadrupole field strength, among others. This paper will discuss the details of the techniques used, the results from several quad-scans preformed at FAST during the electron injector commissioning, and the PYTHON code used to obtain the results.

  1. A Mechanistic Source Term Calculation for a Metal Fuel Sodium Fast Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Grabaskas, David; Bucknor, Matthew; Jerden, James

    2017-06-26

    A mechanistic source term (MST) calculation attempts to realistically assess the transport and release of radionuclides from a reactor system to the environment during a specific accident sequence. The U.S. Nuclear Regulatory Commission (NRC) has repeatedly stated its expectation that advanced reactor vendors will utilize an MST during the U.S. reactor licensing process. As part of a project to examine possible impediments to sodium fast reactor (SFR) licensing in the U.S., an analysis was conducted regarding the current capabilities to perform an MST for a metal fuel SFR. The purpose of the project was to identify and prioritize any gaps in current computational tools, and the associated database, for the accurate assessment of an MST. The results of the study demonstrate that an SFR MST is possible with current tools and data, but several gaps exist that may lead to possibly unacceptable levels of uncertainty, depending on the goals of the MST analysis.

  2. Calculation of Computational Complexity for Radix-2 (p) Fast Fourier Transform Algorithms for Medical Signals.

    Science.gov (United States)

    Amirfattahi, Rassoul

    2013-10-01

    Owing to its simplicity radix-2 is a popular algorithm to implement fast fourier transform. Radix-2(p) algorithms have the same order of computational complexity as higher radices algorithms, but still retain the simplicity of radix-2. By defining a new concept, twiddle factor template, in this paper, we propose a method for exact calculation of multiplicative complexity for radix-2(p) algorithms. The methodology is described for radix-2, radix-2 (2) and radix-2 (3) algorithms. Results show that radix-2 (2) and radix-2 (3) have significantly less computational complexity compared with radix-2. Another interesting result is that while the number of complex multiplications in radix-2 (3) algorithm is slightly more than radix-2 (2), the number of real multiplications for radix-2 (3) is less than radix-2 (2). This is because of the twiddle factors in the form of which need less number of real multiplications and are more frequent in radix-2 (3) algorithm.

  3. Fast Calculation of Abort Return Trajectories for Manned Missions to the Moon

    Science.gov (United States)

    Senent, Juan S.

    2010-01-01

    In order to support the anytime abort requirements of a manned mission to the Moon, the vehicle abort capabilities for the translunar and circumlunar phases of the mission must be studied. Depending on the location of the abort maneuver, the maximum return time to Earth and the available propellant, two different kinds of return trajectories can be calculated: direct and fly-by. This paper presents a new method to compute these return trajectories in a deterministic and fast way without using numerical optimizers. Since no simplifications of the gravity model are required, the resulting trajectories are very accurate and can be used for both mission design and operations. This technique has been extensively used to evaluate the abort capabilities of the Orion/Altair vehicles in the Constellation program for the translunar phase of the mission.

  4. Fast calculation method of computer generated hologram animation for viewpoint parallel shift and rotation using Fourier transform optical system.

    Science.gov (United States)

    Watanabe, Ryosuke; Yamaguchi, Kazuhiro; Sakamoto, Yuji

    2016-01-20

    Computer generated hologram (CGH) animations can be made by switching many CGHs on an electronic display. Some fast calculation methods for CGH animations have been proposed, but one for viewpoint movement has not been proposed. Therefore, we designed a fast calculation method of CGH animations for viewpoint parallel shifts and rotation. A Fourier transform optical system was adopted to expand the viewing angle. The results of experiments were that the calculation time of our method was over 6 times faster than that of the conventional method. Furthermore, the degradation in CGH animation quality was found to be sufficiently small.

  5. Metadyn View: Fast web-based viewer of free energy surfaces calculated by metadynamics

    Science.gov (United States)

    Hošek, Petr; Spiwok, Vojtěch

    2016-01-01

    Metadynamics is a highly successful enhanced sampling technique for simulation of molecular processes and prediction of their free energy surfaces. An in-depth analysis of data obtained by this method is as important as the simulation itself. Although there are several tools to compute free energy surfaces from metadynamics data, they usually lack user friendliness and a build-in visualization part. Here we introduce Metadyn View as a fast and user friendly viewer of bias potential/free energy surfaces calculated by metadynamics in Plumed package. It is based on modern web technologies including HTML5, JavaScript and Cascade Style Sheets (CSS). It can be used by visiting the web site and uploading a HILLS file. It calculates the bias potential/free energy surface on the client-side, so it can run online or offline without necessity to install additional web engines. Moreover, it includes tools for measurement of free energies and free energy differences and data/image export.

  6. SMARTIES: User-friendly codes for fast and accurate calculations of light scattering by spheroids

    Science.gov (United States)

    Somerville, W. R. C.; Auguié, B.; Le Ru, E. C.

    2016-05-01

    We provide a detailed user guide for SMARTIES, a suite of MATLAB codes for the calculation of the optical properties of oblate and prolate spheroidal particles, with comparable capabilities and ease-of-use as Mie theory for spheres. SMARTIES is a MATLAB implementation of an improved T-matrix algorithm for the theoretical modelling of electromagnetic scattering by particles of spheroidal shape. The theory behind the improvements in numerical accuracy and convergence is briefly summarized, with reference to the original publications. Instructions of use, and a detailed description of the code structure, its range of applicability, as well as guidelines for further developments by advanced users are discussed in separate sections of this user guide. The code may be useful to researchers seeking a fast, accurate and reliable tool to simulate the near-field and far-field optical properties of elongated particles, but will also appeal to other developers of light-scattering software seeking a reliable benchmark for non-spherical particles with a challenging aspect ratio and/or refractive index contrast.

  7. Preliminary safety calculations to improve the design of Molten Salt Fast Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Brovchenko, M.; Heuer, D.; Merle-Lucotte, E.; Allibert, M.; Capellan, N.; Ghetta, V.; Laureau, A. [LPSC, CNRS/IN2P3, Grenoble INP, 53,rue des Martyrs, 38026 Grenoble Cedex (France)

    2012-07-01

    Molten salt reactors are liquid fuel reactors so that they are flexible in operation but very different in the safety approach from solid fuel reactors. This study bears on the specific concept named Molten Salt Fast Reactor (MSFR). Since this new nuclear technology is in development, safety is an essential point to be considered all along the R and D studies. This paper presents the first step of the safety approach: the systematic description of the MSFR, limited here to the main systems surrounding the core. This systematic description is the basis on which we will be able to devise accidental scenarios. Thanks to the negative reactivity feedback coefficient, most accidental scenarios lead to reactor shut down. Because of the decay heat generated in the fuel salt, it must be cooled. After the description of the tools developed to calculate the residual heat, the different contributions are discussed in this study. The decay heat of fission products in the MSFR is evaluated to be low (3% of nominal power), mainly due to the reprocessing that transfers the fission products to the gas reprocessing unit. As a result, the contribution of the actinides is significant (0.5% of nominal power). The unprotected loss of heat sink transients are studied in this paper. It appears that slow transients are favorable (> 1 min) to minimize the temperature increase of the fuel salt. This work will be the basis of further safety studies as well as an essential parameter for the design of the draining system. (authors)

  8. Accurate calculation and Matlab based fast realization of merit function's Hesse matrix for the design of multilayer optical coating

    Science.gov (United States)

    Wu, Su-Yong; Long, Xing-Wu; Yang, Kai-Yong

    2009-09-01

    To improve the current status of home multilayer optical coating design with low speed and poor efficiency when a large layer number occurs, the accurate calculation and fast realization of merit function’s gradient and Hesse matrix is pointed out. Based on the matrix method to calculate the spectral properties of multilayer optical coating, an analytic model is established theoretically. And the corresponding accurate and fast computation is successfully achieved by programming with Matlab. Theoretical and simulated results indicate that this model is mathematically strict and accurate, and its maximal precision can reach floating-point operations in the computer, with short time and fast speed. Thus it is very suitable to improve the optimal search speed and efficiency of local optimization methods based on the derivatives of merit function. It has outstanding performance in multilayer optical coating design with a large layer number.

  9. Fast calculation of computer-generated-hologram on AMD HD5000 series GPU and OpenCL

    CERN Document Server

    Shimobaba, Tomoyoshi; Masuda, Nobuyuki; Ichihashi, Yasuyuki; Takada, Naoki

    2010-01-01

    In this paper, we report fast calculation of a computer-generated-hologram using a new architecture of the HD5000 series GPU (RV870) made by AMD and its new software development environment, OpenCL. Using a RV870 GPU and OpenCL, we can calculate 1,920 * 1,024 resolution of a CGH from a 3D object consisting of 1,024 points in 30 milli-seconds. The calculation speed realizes a speed approximately two times faster than that of a GPU made by NVIDIA.

  10. Fast calculation of computer-generated-hologram on AMD HD5000 series GPU and OpenCL.

    Science.gov (United States)

    Shimobaba, Tomoyoshi; Ito, Tomoyoshi; Masuda, Nobuyuki; Ichihashi, Yasuyuki; Takada, Naoki

    2010-05-10

    In this paper, we report fast calculation of a computer-generated-hologram using a new architecture of the HD5000 series GPU (RV870) made by AMD and its new software development environment, OpenCL. Using a RV870 GPU and OpenCL, we can calculate 1,920 x 1,024 resolution of a CGH from a 3D object consisting of 1,024 points in 30 milli-seconds. The calculation speed realizes a speed approximately two times faster than that of a GPU made by NVIDIA. (c) 2010 Optical Society of America.

  11. Fast calculation method for computer-generated cylindrical holograms based on the three-dimensional Fourier spectrum.

    Science.gov (United States)

    Sando, Yusuke; Barada, Daisuke; Jackin, Boaz Jessie; Yatagai, Toyohiko

    2013-12-01

    The relation between a three-dimensional (3D) object and its diffracted wavefront in the 3D Fourier space is discussed at first and then a rigorous diffraction formula onto cylindrical surfaces is derived. The azimuthal direction and the spatial frequency direction corresponding to height can be expressed with a one-dimensional (1D) convolution integral and a 1D inverse Fourier transform in the 3D Fourier space, respectively, and fast Fourier transforms are available for fast calculation. A numerical simulation of a diffracted wavefront on cylindrical surfaces is presented. An alternative optical experiment equivalent of the optical reconstruction from cylindrical holograms is also demonstrated.

  12. FAST

    DEFF Research Database (Denmark)

    Zuidmeer-Jongejan, Laurian; Fernandez-Rivas, Montserrat; Poulsen, Lars K.

    2012-01-01

    ABSTRACT: The FAST project (Food Allergy Specific Immunotherapy) aims at the development of safe and effective treatment of food allergies, targeting prevalent, persistent and severe allergy to fish and peach. Classical allergen-specific immunotherapy (SIT), using subcutaneous injections with aqu......ABSTRACT: The FAST project (Food Allergy Specific Immunotherapy) aims at the development of safe and effective treatment of food allergies, targeting prevalent, persistent and severe allergy to fish and peach. Classical allergen-specific immunotherapy (SIT), using subcutaneous injections...... with aqueous food extracts may be effective but has proven to be accompanied by too many anaphylactic side-effects. FAST aims to develop a safe alternative by replacing food extracts with hypoallergenic recombinant major allergens as the active ingredients of SIT. Both severe fish and peach allergy are caused...... in depth serological and cellular immune analyses will be performed, allowing identification of novel biomarkers for monitoring treatment efficacy. FAST aims at improving the quality of life of food allergic patients by providing a safe and effective treatment that will significantly lower their threshold...

  13. The fast neutron fluence and the activation detector activity calculations using the effective source method and the adjoint function

    Energy Technology Data Exchange (ETDEWEB)

    Hep, J.; Konecna, A.; Krysl, V.; Smutny, V. [Calculation Dept., Skoda JS plc, Orlik 266, 31606 Plzen (Czech Republic)

    2011-07-01

    This paper describes the application of effective source in forward calculations and the adjoint method to the solution of fast neutron fluence and activation detector activities in the reactor pressure vessel (RPV) and RPV cavity of a VVER-440 reactor. Its objective is the demonstration of both methods on a practical task. The effective source method applies the Boltzmann transport operator to time integrated source data in order to obtain neutron fluence and detector activities. By weighting the source data by time dependent decay of the detector activity, the result of the calculation is the detector activity. Alternatively, if the weighting is uniform with respect to time, the result is the fluence. The approach works because of the inherent linearity of radiation transport in non-multiplying time-invariant media. Integrated in this way, the source data are referred to as the effective source. The effective source in the forward calculations method thereby enables the analyst to replace numerous intensive transport calculations with a single transport calculation in which the time dependence and magnitude of the source are correctly represented. In this work, the effective source method has been expanded slightly in the following way: neutron source data were performed with few group method calculation using the active core calculation code MOBY-DICK. The follow-up neutron transport calculation was performed using the neutron transport code TORT to perform multigroup calculations. For comparison, an alternative method of calculation has been used based upon adjoint functions of the Boltzmann transport equation. Calculation of the three-dimensional (3-D) adjoint function for each required computational outcome has been obtained using the deterministic code TORT and the cross section library BGL440. Adjoint functions appropriate to the required fast neutron flux density and neutron reaction rates have been calculated for several significant points within the RPV

  14. Time-dependent calculations of transfer ionization by fast proton-helium collision in one-dimensional kinematics

    OpenAIRE

    Serov, Vladislav V.; Kheifets, A. S.

    2014-01-01

    We analyze a transfer ionization (TI) reaction in the fast proton-helium collision $\\rm H^+ + He \\to H^0 + He^{2+} + e^-$ by solving a time-dependent Schr\\"odinger equation (TDSE) under the classical projectile motion approximation in one-dimensional kinematics. In addition, we construct various time independent analogues of our model using lowest order perturbation theory in the form of the Born series. By comparing various aspects of the TDSE and the Born series calculations, we conclude th...

  15. Fast calculations of the gradient and the Hessian in the time-domain global electromagnetic induction inverse problem

    Science.gov (United States)

    Maksimov, M. A.; Velímský, J.

    2017-07-01

    The deterministic approach to the inverse problem of the time-domain electromagnetic induction in a spherical Earth requires the calculation of the first derivative of a misfit function in every step of the minimization process. In addition, an a-posteriori error analysis can benefit from the knowledge of the Hessian, the matrix of the second derivatives. We present the derivation of the formulas for the fast calculation of the misfit gradient, the Hessian, and the Hessian-vector product, based on the solution of an adjoint problem. We validate our results on a synthetic model against a slow finite-difference scheme.

  16. Fast calculation of the maximum power point of photovoltaic generators under partial shading

    OpenAIRE

    Carlos Andres Ramos-Paja; Luz Adriana Trejos-Grisales; Javier Herrera-Murcia

    2016-01-01

    This paper presents a method to calculate the energy production of photovoltaic generators considering partial shading or mismatched conditions. The proposed method is based on the complete one-diode model including the bypass diode in its exponential form, where the current and voltage values of the modules composing the photovoltaic panel array are calculated without using the Lambert-W function. In addition, the method introduces a procedure to calculate the vicinity of the maximum power p...

  17. A method to fast determine the coupling coefficients in CI calculation

    Institute of Scientific and Technical Information of China (English)

    甘正汀; 苏克和; 王育邠; 文振翼

    1999-01-01

    A new algorithm for evaluating the coupling coefficients and the addresses of molecular integrals in configuration interaction (CI) calculations is presented, which leads to an improved CI calculation program CGUGA. The validity and efficiency of the new code are compared with other programs, such as MELD and GAUSSIAN-94.

  18. Fast, accurate and stable scattering calculation method with application to finite sized photonic crystal waveguides

    DEFF Research Database (Denmark)

    Kristensen, Philip Trøst; Lodahl, Peter; Mørk, Jesper

    2009-01-01

    We present a multipole solution to the Lippmann-Schwinger equation for electromagnetic scattering in inhomogeneous geometries. The method is illustrated by calculating the Green’s function for a finite sized two-dimensional photonic crystal waveguide.......We present a multipole solution to the Lippmann-Schwinger equation for electromagnetic scattering in inhomogeneous geometries. The method is illustrated by calculating the Green’s function for a finite sized two-dimensional photonic crystal waveguide....

  19. A fast, simple, and naturally machine-precision algorithm for calculating both symmetric and asymmetric MT2, for any physical inputs

    CERN Document Server

    Lester, Chrisopher G

    2014-01-01

    This document describes a stransverse-mass calculation algorithm that has better numerical stability, and therefore accuracy, than the fastest existing implementations. The new algorithm naturally permits computation of MT2 to machine-precision for any valid set of inputs. In addition to being more accurate than existing fast calculators, the new implementation is arguably simpler to understand, comprises fewer lines of active code, and provides the first fast machine-precision asymmetric-MT2 calculator known to the authors.

  20. Fast Atomic Charge Calculation for Implementation into a Polarizable Force Field and Application to an Ion Channel Protein

    Directory of Open Access Journals (Sweden)

    Raiker Witter

    2015-01-01

    Full Text Available Polarization of atoms plays a substantial role in molecular interactions. Class I and II force fields mostly calculate with fixed atomic charges which can cause inadequate descriptions for highly charged molecules, for example, ion channels or metalloproteins. Changes in charge distributions can be included into molecular mechanics calculations by various methods. Here, we present a very fast computational quantum mechanical method, the Bond Polarization Theory (BPT. Atomic charges are obtained via a charge calculation method that depend on the 3D structure of the system in a similar way as atomic charges of ab initio calculations. Different methods of population analysis and charge calculation methods and their dependence on the basis set were investigated. A refined parameterization yielded excellent correlation of R=0.9967. The method was implemented in the force field COSMOS-NMR and applied to the histidine-tryptophan-complex of the transmembrane domain of the M2 protein channel of influenza A virus. Our calculations show that moderate changes of side chain torsion angle χ1 and small variations of χ2 of Trp-41 are necessary to switch from the inactivated into the activated state; and a rough two-side jump model of His-37 is supported for proton gating in accordance with a flipping mechanism.

  1. Fast calculations of the spectral diffuse-to-global ratios for approximating spectral irradiance at the street canyon level

    Science.gov (United States)

    Carrasco-Hernandez, Roberto; Smedley, Andrew R. D.; Webb, Ann R.

    2016-05-01

    Two radiative transfer models are presented that simplify calculations of street canyon spectral irradiances with minimum data input requirements, allowing better assessment of urban exposures than can be provided by standard unobstructed radiation measurements alone. Fast calculations improve the computational performance of radiation models, when numerous repetitions are required in time and location. The core of the models is the calculation of the spectral diffuse-to-global ratios (DGR) from an unobstructed global spectral measurement. The models are based on, and have been tested against, outcomes of the SMARTS2 algorithm (i.e. Simple Model of the Atmospheric Radiative Transfer of Sunshine). The modelled DGRs can then be used to partition global spectral irradiance values into their direct and diffuse components for different solar zenith angles. Finally, the effects of canyon obstructions can be evaluated independently on the direct and diffuse components, which are then recombined to give the total canyon irradiance. The first model allows ozone and aerosol inputs, while the second provides a further simplification, restricted to average ozone and aerosol contents but specifically designed for faster calculations. To assess the effect of obstructions and validate the calculations, a set of experiments with simulated obstructions (simulated canyons) were performed. The greatest source of uncertainty in the simplified calculations is in the treatment of diffuse radiation. The measurement-model agreement is therefore dependent on the region of the sky obscured and ranges from <5 % at all wavelengths to 20-40 % (wavelength dependent) when diffuse sky only is visible from the canyon.

  2. Monte Carlo fast dose calculator for proton radiotherapy: application to a voxelized geometry representing a patient with prostate cancer.

    Science.gov (United States)

    Yepes, Pablo; Randeniya, Sharmalee; Taddei, Phillip J; Newhauser, Wayne D

    2009-01-07

    The Monte Carlo method is used to provide accurate dose estimates in proton radiation therapy research. While it is more accurate than commonly used analytical dose calculations, it is computationally intense. The aim of this work was to characterize for a clinical setup the fast dose calculator (FDC), a Monte Carlo track-repeating algorithm based on GEANT4. FDC was developed to increase computation speed without diminishing dosimetric accuracy. The algorithm used a database of proton trajectories in water to calculate the dose of protons in heterogeneous media. The extrapolation from water to 41 materials was achieved by scaling the proton range and the scattering angles. The scaling parameters were obtained by comparing GEANT4 dose distributions with those calculated with FDC for homogeneous phantoms. The FDC algorithm was tested by comparing dose distributions in a voxelized prostate cancer patient as calculated with well-known Monte Carlo codes (GEANT4 and MCNPX). The track-repeating approach reduced the CPU time required for a complete dose calculation in a voxelized patient anatomy by more than two orders of magnitude, while on average reproducing the results from the Monte Carlo predictions within 2% in terms of dose and within 1 mm in terms of distance.

  3. A fast and flexible library-based thick-mask near-field calculation method

    Science.gov (United States)

    Ma, Xu; Gao, Jie; Chen, Xuanbo; Dong, Lisong; Li, Yanqiu

    2015-03-01

    Aerial image calculation is the basis of the current lithography simulation. As the critical dimension (CD) of the integrated circuits continuously shrinks, the thick mask near-field calculation has increasing influence on the accuracy and efficiency of the entire aerial image calculation process. This paper develops a flexible librarybased approach to significantly improve the efficiency of the thick mask near-field calculation compared to the rigorous modeling method, while leading to much higher accuracy than the Kirchhoff approximation method. Specifically, a set of typical features on the fullchip are selected to serve as the training data, whose near-fields are pre-calculated and saved in the library. Given an arbitrary test mask, we first decompose it into convex corners, concave corners and edges, afterwards match each patch to the training layouts based on nonparametric kernel regression. Subsequently, we use the matched near-fields in the library to replace the mask patches, and rapidly synthesize the near-field for the entire test mask. Finally, a data-fitting method is proposed to improve the accuracy of the synthesized near-field based on least square estimate (LSE). We use a pair of two-dimensional mask patterns to test our method. Simulations show that the proposed method can significantly speed up the current FDTD method, and effectively improve the accuracy of the Kirchhoff approximation method.

  4. Measured and calculated fast neutron spectra in a depleted uranium and lithium hydride shielded reactor

    Science.gov (United States)

    Lahti, G. P.; Mueller, R. A.

    1973-01-01

    Measurements of MeV neutron were made at the surface of a lithium hydride and depleted uranium shielded reactor. Four shield configurations were considered: these were assembled progressively with cylindrical shells of 5-centimeter-thick depleted uranium, 13-centimeter-thick lithium hydride, 5-centimeter-thick depleted uranium, 13-centimeter-thick lithium hydride, 5-centimeter-thick depleted uranium, and 3-centimeter-thick depleted uranium. Measurements were made with a NE-218 scintillation spectrometer; proton pulse height distributions were differentiated to obtain neutron spectra. Calculations were made using the two-dimensional discrete ordinates code DOT and ENDF/B (version 3) cross sections. Good agreement between measured and calculated spectral shape was observed. Absolute measured and calculated fluxes were within 50 percent of one another; observed discrepancies in absolute flux may be due to cross section errors.

  5. Fast pencil beam dose calculation for proton therapy using a double-Gaussian beam model

    Directory of Open Access Journals (Sweden)

    Joakim eda Silva

    2015-12-01

    Full Text Available The highly conformal dose distributions produced by scanned proton pencil beams are more sensitive to motion and anatomical changes than those produced by conventional radiotherapy. The ability to calculate the dose in real time as it is being delivered would enable, for example, online dose monitoring, and is therefore highly desirable. We have previously described an implementation of a pencil beam algorithm running on graphics processing units (GPUs intended specifically for online dose calculation. Here we present an extension to the dose calculation engine employing a double-Gaussian beam model to better account for the low-dose halo. To the best of our knowledge, it is the first such pencil beam algorithm for proton therapy running on a GPU. We employ two different parametrizations for the halo dose, one describing the distribution of secondary particles from nuclear interactions found in the literature and one relying on directly fitting the model to Monte Carlo simulations of pencil beams in water. Despite the large width of the halo contribution, we show how in either case the second Gaussian can be included whilst prolonging the calculation of the investigated plans by no more than 16%, or the calculation of the most time-consuming energy layers by about 25%. Further, the calculation time is relatively unaffected by the parametrization used, which suggests that these results should hold also for different systems. Finally, since the implementation is based on an algorithm employed by a commercial treatment planning system, it is expected that with adequate tuning, it should be able to reproduce the halo dose from a general beam line with sufficient accuracy.

  6. A localized basis that allows fast and accurate second order Moller-Plesset calculations

    Energy Technology Data Exchange (ETDEWEB)

    Subotnik, Joseph E.; Head-Gordon, Martin

    2004-10-27

    We present a method for computing a basis of localized orthonormal orbitals (both occupied and virtual), in whose representation the Fock matrix is extremely diagonal-dominant. The existence of these orbitals is shown empirically to be sufficient for achieving highly accurate MP@ energies, calculated according to Kapuy's method. This method (which we abbreviate KMP2), which involves a different partitioning of the n-electron Hamiltonian, scales at most quadratically with potential for linearity in the number of electrons. As such, we believe the KMP2 algorithm presented here could be the basis of a viable approach to local correlation calculations.

  7. Fast calculate the parameters of surface acoustic wave coupling-of-modes model

    Institute of Scientific and Technical Information of China (English)

    LIU Jiansheng; HE Shitang

    2007-01-01

    Accurate solutions of acoustic waves in piezoelectric substrate and metal film as layered structure were obtained. Phase velocity, electromechanical coupling coefficient and static capacitance were calculated based upon the solutions. Chen and Haus' theory was used to analyze surface acoustic waves in shorten gratings with single finger every period and a reflection coefficient expression of one strip was presented. Parameters of aluminum on X112°Y LiTaO3 and gold on ST-quartz were calculated. The results agreed well with those from Ken-ya Hashimoto's theory. The reflection coefficient of gold on ST-quartz was measured to verify the theoretical result.

  8. Fast and Accurate Calculation of Protein Depth by Euclidean Distance Transform

    Science.gov (United States)

    Xu, Dong; Li, Hua; Zhang, Yang

    2014-01-01

    The depth of each atom/residue in a protein structure is a key attribution that has been widely used in protein structure modeling and function annotation. However, the accurate calculation of depth is time consuming. Here, we propose to use the Euclidean distance transform (EDT) to calculate the depth, which conveniently converts the protein structure to a 3D gray-scale image with each pixel labeling the minimum distance of the pixel to the surface of the molecule (i.e. the depth). We tested the proposed EDT method on a set of 261 non-redundant protein structures. The data show that the EDT method is 2.6 times faster than the widely used method by Chakravarty and Varadarajan. The depth value by EDT method is also highly accurate, which is almost identical to the depth calculated by exhaustive search (Pearson’s correlation coefficient≈1). We believe the EDT-based depth calculation program can be used as an efficient tool to assist the studies of protein fold recognition and structure-based function annotation. PMID:25035865

  9. Fast algorithms for calculating laser wavefront phase compensation given noisy measurements of phase gradient

    Science.gov (United States)

    Gavel, Don

    1989-09-01

    Laser light propagating through atmosphere will become distorted as a result of the changing index of refraction along the light path. Wavefront distortions can be actively compensated using adaptive optic systems, which sense the wavefront aberations and compensate by changing the shape of a reflecting surface. Corrections must be done rapidly in order to keep up with the variations in the atmosphere. Numerically, the calculation of the correcting surface is a least-squares fit problem. However, since a typical adaptive optic system has a large number of actuators and sensors, the ordinary solution methods, such as Gaussian elimination, are infeasible for real time application. Instead, advantage must be taken of the structure and sparseness of the equations in order to speed up the calculation. The algorithm proposed requires only O(nq) calculation steps and uses only O(n) memory storage, where n is the total number of actuators and q is the influence width of a single actuator. The derivation of the proposed algorithm, proofs of convergence, and results of several test runs are presented. The algorithm was incorporated into Y division's ORACLE simulation code where it is used to calculate the phase conjugate surfaces necessary to precompensate a high powered laser beam for atmospheric propagation.

  10. Calculation of Resistivity of the Insulating Layer in Tunnelling-Magnetoresistive Head by Fast Green Function Method

    Institute of Scientific and Technical Information of China (English)

    WEI Dan; PIAO Kun; QIN Jian; DONG Zhong

    2005-01-01

    @@ We calculate the resistivity of the insulating layer in a tunnelling-magnetoresistive (TMR) magnetic head byusing the Landauer-Büttiker formula with a fast Green function method, where a recursive process with a faster simulation speed and higher accuracy is carried out to substitute the inversion of Green's matrix. A tight-binding model with an energy barrier △ E is utilized to simulate the magnetoresistive tunnelling junction in the TMR head. The resistivity of the insulating layer is 2.6 × 105μΩcm with two oxygen-ion layers and △E = 2.5 eV, which agrees with the experimental data.

  11. An unadjusted 25 group neutron cross section set for fast reactor core calculations from JENDL-2 library

    Energy Technology Data Exchange (ETDEWEB)

    Devan, K.; Gopalakrishnan, V.; Lee, S.M. [Nuclear Data Section Indira Ganhi Centre for Atomic Research, Tamilnadu (India)

    1994-12-31

    We have created a 25 group neutron cross section set (IGCJENDL) for nuclides of interest to LMFBRs from the Japanese Evaluated Nuclear Data Library - Version 2 (JENDL-2) in the format of French adjusted Cadarache Version 2 set (1969). The integral validation of IGCJENDL set was done by analyzing nine fast critical assemblies proposed by Cross Section Evaluation Working Group (CSEWG). The calculated integral parameters agreed reasonably well with the reported measured values. It is found that this set predicts the integral parameters, k-eff in particular, close to that predicted by adjusted CARNAVAL IV (French) or BNAB-78 (Russian) sets, for a 1200 MWe theoretical benchmark, representing a large power reactor.

  12. GPU-based fast Monte Carlo simulation for radiotherapy dose calculation

    CERN Document Server

    Jia, Xun; Graves, Yan Jiang; Folkerts, Michael; Jiang, Steve B

    2011-01-01

    Monte Carlo (MC) simulation is commonly considered to be the most accurate dose calculation method in radiotherapy. However, its efficiency still requires improvement for many routine clinical applications. In this paper, we present our recent progress towards the development a GPU-based MC dose calculation package, gDPM v2.0. It utilizes the parallel computation ability of a GPU to achieve high efficiency, while maintaining the same particle transport physics as in the original DPM code and hence the same level of simulation accuracy. In GPU computing, divergence of execution paths between threads can considerably reduce the efficiency. Since photons and electrons undergo different physics and hence attain different execution paths, we use a simulation scheme where photon transport and electron transport are separated to partially relieve the thread divergence issue. High performance random number generator and hardware linear interpolation are also utilized. We have also developed various components to hand...

  13. Dose calculation algorithm of fast fine-heterogeneity correction for heavy charged particle radiotherapy.

    Science.gov (United States)

    Kanematsu, Nobuyuki

    2011-04-01

    This work addresses computing techniques for dose calculations in treatment planning with proton and ion beams, based on an efficient kernel-convolution method referred to as grid-dose spreading (GDS) and accurate heterogeneity-correction method referred to as Gaussian beam splitting. The original GDS algorithm suffered from distortion of dose distribution for beams tilted with respect to the dose-grid axes. Use of intermediate grids normal to the beam field has solved the beam-tilting distortion. Interplay of arrangement between beams and grids was found as another intrinsic source of artifact. Inclusion of rectangular-kernel convolution in beam transport, to share the beam contribution among the nearest grids in a regulatory manner, has solved the interplay problem. This algorithmic framework was applied to a tilted proton pencil beam and a broad carbon-ion beam. In these cases, while the elementary pencil beams individually split into several tens, the calculation time increased only by several times with the GDS algorithm. The GDS and beam-splitting methods will complementarily enable accurate and efficient dose calculations for radiotherapy with protons and ions. Copyright © 2010 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  14. Regulatory Technology Development Plan - Sodium Fast Reactor. Mechanistic Source Term - Trial Calculation. Work Plan

    Energy Technology Data Exchange (ETDEWEB)

    Grabaskas, David [Argonne National Lab. (ANL), Argonne, IL (United States); Bucknor, Matthew [Argonne National Lab. (ANL), Argonne, IL (United States); Jerden, James [Argonne National Lab. (ANL), Argonne, IL (United States); Brunett, Acacia J. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-02-01

    The overall objective of the SFR Regulatory Technology Development Plan (RTDP) effort is to identify and address potential impediments to the SFR regulatory licensing process. In FY14, an analysis by Argonne identified the development of an SFR-specific MST methodology as an existing licensing gap with high regulatory importance and a potentially long lead-time to closure. This work was followed by an initial examination of the current state-of-knowledge regarding SFR source term development (ANLART-3), which reported several potential gaps. Among these were the potential inadequacies of current computational tools to properly model and assess the transport and retention of radionuclides during a metal fuel pool-type SFR core damage incident. The objective of the current work is to determine the adequacy of existing computational tools, and the associated knowledge database, for the calculation of an SFR MST. To accomplish this task, a trial MST calculation will be performed using available computational tools to establish their limitations with regard to relevant radionuclide release/retention/transport phenomena. The application of existing modeling tools will provide a definitive test to assess their suitability for an SFR MST calculation, while also identifying potential gaps in the current knowledge base and providing insight into open issues regarding regulatory criteria/requirements. The findings of this analysis will assist in determining future research and development needs.

  15. Fast calculation of the maximum power point of photovoltaic generators under partial shading

    Directory of Open Access Journals (Sweden)

    Carlos Andres Ramos-Paja

    2016-09-01

    Full Text Available This paper presents a method to calculate the energy production of photovoltaic generators considering partial shading or mismatched conditions. The proposed method is based on the complete one-diode model including the bypass diode in its exponential form, where the current and voltage values of the modules composing the photovoltaic panel array are calculated without using the Lambert-W function. In addition, the method introduces a procedure to calculate the vicinity of the maximum power points, which enables the reduction of the operations required to obtain the global maximum. The proposed method provides short simulation times and high accuracy. On the other hand, since the method does not require complex mathematical functions, it can be implemented straightforwardly on known software packages and development languages such as C and C++. Those characteristics make this method a useful tool to evaluate the economic viability and return-of-investment time of photovoltaic installations. Simulation results and comparisons with a classical procedure confirm the good performance of the proposed method in terms of execution time and accuracy.

  16. On the relation between correlation dimension, approximate entropy and sample entropy parameters, and a fast algorithm for their calculation

    Science.gov (United States)

    Zurek, Sebastian; Guzik, Przemyslaw; Pawlak, Sebastian; Kosmider, Marcin; Piskorski, Jaroslaw

    2012-12-01

    We explore the relation between correlation dimension, approximate entropy and sample entropy parameters, which are commonly used in nonlinear systems analysis. Using theoretical considerations we identify the points which are shared by all these complexity algorithms and show explicitly that the above parameters are intimately connected and mutually interdependent. A new geometrical interpretation of sample entropy and correlation dimension is provided and the consequences for the interpretation of sample entropy, its relative consistency and some of the algorithms for parameter selection for this quantity are discussed. To get an exact algorithmic relation between the three parameters we construct a very fast algorithm for simultaneous calculations of the above, which uses the full time series as the source of templates, rather than the usual 10%. This algorithm can be used in medical applications of complexity theory, as it can calculate all three parameters for a realistic recording of 104 points within minutes with the use of an average notebook computer.

  17. The use of the neutronic calculation code CORNER for evaluating the protection of fast neutron reactor and CNFC equipment

    Science.gov (United States)

    Shekhanova, M. E.

    2017-01-01

    In this paper we propose a method of using neutronic calculation code CORNER to the analysis of experiments on the protection of fast neutron reactor and CNFC equipment. An example of Winfrith Graphite Benchmark experiment calculation using this approach is presented. This task can be considered as one step in the general theme of the safety analysis of FR with liquid metal coolant, their fuel cycles and related equipment. CORNER implement a solution of the kinetic equation with a source in the three-dimensional hexagonal geometry based on Sn-method. The purpose of this paper is a demonstration of the application of CORNER’s possibilities for the analysis of the actual reactor problems.

  18. AFMPB: An adaptive fast multipole Poisson-Boltzmann solver for calculating electrostatics in biomolecular systems

    Science.gov (United States)

    Lu, Benzhuo; Cheng, Xiaolin; Huang, Jingfang; McCammon, J. Andrew

    2013-11-01

    A Fortran program package is introduced for rapid evaluation of the electrostatic potentials and forces in biomolecular systems modeled by the linearized Poisson-Boltzmann equation. The numerical solver utilizes a well-conditioned boundary integral equation (BIE) formulation, a node-patch discretization scheme, a Krylov subspace iterative solver package with reverse communication protocols, and an adaptive new version of the fast multipole method in which the exponential expansions are used to diagonalize the multipole-to-local translations. The program and its full description, as well as several closely related libraries and utility tools are available at http://lsec.cc.ac.cn/~lubz/afmpb.html and a mirror site at http://mccammon.ucsd.edu/. This paper is a brief summary of the program: the algorithms, the implementation and the usage. Restrictions: Only three or six significant digits options are provided in this version. Unusual features: Most of the codes are in Fortran77 style. Memory allocation functions from Fortran90 and above are used in a few subroutines. Additional comments: The current version of the codes is designed and written for single core/processor desktop machines. Check http://lsec.cc.ac.cn/lubz/afmpb.html for updates and changes. Running time: The running time varies with the number of discretized elements (N) in the system and their distributions. In most cases, it scales linearly as a function of N.

  19. GPU-based fast Monte Carlo simulation for radiotherapy dose calculation.

    Science.gov (United States)

    Jia, Xun; Gu, Xuejun; Graves, Yan Jiang; Folkerts, Michael; Jiang, Steve B

    2011-11-21

    Monte Carlo (MC) simulation is commonly considered to be the most accurate dose calculation method in radiotherapy. However, its efficiency still requires improvement for many routine clinical applications. In this paper, we present our recent progress toward the development of a graphics processing unit (GPU)-based MC dose calculation package, gDPM v2.0. It utilizes the parallel computation ability of a GPU to achieve high efficiency, while maintaining the same particle transport physics as in the original dose planning method (DPM) code and hence the same level of simulation accuracy. In GPU computing, divergence of execution paths between threads can considerably reduce the efficiency. Since photons and electrons undergo different physics and hence attain different execution paths, we use a simulation scheme where photon transport and electron transport are separated to partially relieve the thread divergence issue. A high-performance random number generator and a hardware linear interpolation are also utilized. We have also developed various components to handle the fluence map and linac geometry, so that gDPM can be used to compute dose distributions for realistic IMRT or VMAT treatment plans. Our gDPM package is tested for its accuracy and efficiency in both phantoms and realistic patient cases. In all cases, the average relative uncertainties are less than 1%. A statistical t-test is performed and the dose difference between the CPU and the GPU results is not found to be statistically significant in over 96% of the high dose region and over 97% of the entire region. Speed-up factors of 69.1 ∼ 87.2 have been observed using an NVIDIA Tesla C2050 GPU card against a 2.27 GHz Intel Xeon CPU processor. For realistic IMRT and VMAT plans, MC dose calculation can be completed with less than 1% standard deviation in 36.1 ∼ 39.6 s using gDPM.

  20. Improved Accuracy of the Inherent Shrinkage Method for Fast and More Reliable Welding Distortion Calculations

    Science.gov (United States)

    Mendizabal, A.; González-Díaz, J. B.; San Sebastián, M.; Echeverría, A.

    2016-07-01

    This paper describes the implementation of a simple strategy adopted for the inherent shrinkage method (ISM) to predict welding-induced distortion. This strategy not only makes it possible for the ISM to reach accuracy levels similar to the detailed transient analysis method (considered the most reliable technique for calculating welding distortion) but also significantly reduces the time required for these types of calculations. This strategy is based on the sequential activation of welding blocks to account for welding direction and transient movement of the heat source. As a result, a significant improvement in distortion prediction is achieved. This is demonstrated by experimentally measuring and numerically analyzing distortions in two case studies: a vane segment subassembly of an aero-engine, represented with 3D-solid elements, and a car body component, represented with 3D-shell elements. The proposed strategy proves to be a good alternative for quickly estimating the correct behaviors of large welded components and may have important practical applications in the manufacturing industry.

  1. Fast CPU-based Monte Carlo simulation for radiotherapy dose calculation.

    Science.gov (United States)

    Ziegenhein, Peter; Pirner, Sven; Ph Kamerling, Cornelis; Oelfke, Uwe

    2015-08-07

    Monte-Carlo (MC) simulations are considered to be the most accurate method for calculating dose distributions in radiotherapy. Its clinical application, however, still is limited by the long runtimes conventional implementations of MC algorithms require to deliver sufficiently accurate results on high resolution imaging data. In order to overcome this obstacle we developed the software-package PhiMC, which is capable of computing precise dose distributions in a sub-minute time-frame by leveraging the potential of modern many- and multi-core CPU-based computers. PhiMC is based on the well verified dose planning method (DPM). We could demonstrate that PhiMC delivers dose distributions which are in excellent agreement to DPM. The multi-core implementation of PhiMC scales well between different computer architectures and achieves a speed-up of up to 37[Formula: see text] compared to the original DPM code executed on a modern system. Furthermore, we could show that our CPU-based implementation on a modern workstation is between 1.25[Formula: see text] and 1.95[Formula: see text] faster than a well-known GPU implementation of the same simulation method on a NVIDIA Tesla C2050. Since CPUs work on several hundreds of GB RAM the typical GPU memory limitation does not apply for our implementation and high resolution clinical plans can be calculated.

  2. Fast LiH destruction in reaction with H: quantum calculations and astrophysical consequences

    CERN Document Server

    Bovino, S; Gianturco, F A; 10.1088/0004-637X/699/1/383

    2009-01-01

    We present a quantum-mechanical study of the exothermic 7LiH reaction with H. Accurate reactive probabilities and rate coefficients are obtained by solving the Schrodinger equation for the motion of the three nuclei on a single Born-Oppenheimer potential energy surface (PES) and using a coupled-channel hyperspherical coordinate method. Our new rates indeed confirm earlier, qualitative predictions and some previous theoretical calculations, as discussed in the main text. In the astrophysical domain we find that the depletion process largely dominates for redshift (z) between 400 and 100, a range significant for early Universe models. This new result from first-principle calculations leads us to definitively surmise that LiH should be already destroyed when the survival processes become important. Because of this very rapid depletion reaction, the fractional abundance of LiH is found to be drastically reduced, so that it should be very difficult to manage to observe it as an imprinted species in the cosmic back...

  3. Validation of fast Monte Carlo dose calculation in small animal radiotherapy with EBT3 radiochromic films

    Science.gov (United States)

    Noblet, C.; Chiavassa, S.; Smekens, F.; Sarrut, D.; Passal, V.; Suhard, J.; Lisbona, A.; Paris, F.; Delpon, G.

    2016-05-01

    In preclinical studies, the absorbed dose calculation accuracy in small animals is fundamental to reliably investigate and understand observed biological effects. This work investigated the use of the split exponential track length estimator (seTLE), a new kerma based Monte Carlo dose calculation method for preclinical radiotherapy using a small animal precision micro irradiator, the X-RAD 225Cx. Monte Carlo modelling of the irradiator with GATE/GEANT4 was extensively evaluated by comparing measurements and simulations for half-value layer, percent depth dose, off-axis profiles and output factors in water and water-equivalent material for seven circular fields, from 20 mm down to 1 mm in diameter. Simulated and measured dose distributions in cylinders of water obtained for a 360° arc were also compared using dose, distance-to-agreement and gamma-index maps. Simulations and measurements agreed within 3% for all static beam configurations, with uncertainties estimated to 1% for the simulation and 3% for the measurements. Distance-to-agreement accuracy was better to 0.14 mm. For the arc irradiations, gamma-index maps of 2D dose distributions showed that the success rate was higher than 98%, except for the 0.1 cm collimator (92%). Using the seTLE method, MC simulations compute 3D dose distributions within minutes for realistic beam configurations with a clinically acceptable accuracy for beam diameter as small as 1 mm.

  4. Regulatory Technology Development Plan - Sodium Fast Reactor: Mechanistic Source Term – Trial Calculation

    Energy Technology Data Exchange (ETDEWEB)

    Grabaskas, David [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Bucknor, Matthew [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Jerden, James [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Brunett, Acacia J. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Denman, Matthew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Nuclear Engineering Division; Clark, Andrew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Nuclear Engineering Division; Denning, Richard S. [Consultant, Columbus, OH (United States)

    2016-10-01

    The potential release of radioactive material during a plant incident, referred to as the source term, is a vital design metric and will be a major focus of advanced reactor licensing. The U.S. Nuclear Regulatory Commission has stated an expectation for advanced reactor vendors to present a mechanistic assessment of the potential source term in their license applications. The mechanistic source term presents an opportunity for vendors to realistically assess the radiological consequences of an incident and may allow reduced emergency planning zones and smaller plant sites. However, the development of a mechanistic source term for advanced reactors is not without challenges, as there are often numerous phenomena impacting the transportation and retention of radionuclides. This project sought to evaluate U.S. capabilities regarding the mechanistic assessment of radionuclide release from core damage incidents at metal fueled, pool-type sodium fast reactors (SFRs). The purpose of the analysis was to identify, and prioritize, any gaps regarding computational tools or data necessary for the modeling of radionuclide transport and retention phenomena. To accomplish this task, a parallel-path analysis approach was utilized, as shown below. One path, led by Argonne and Sandia National Laboratories, sought to perform a mechanistic source term assessment using available codes, data, and models, with the goal to identify gaps in the current knowledge base. The second path, performed by an independent contractor, performed sensitivity analyses to determine the importance of particular radionuclides and transport phenomena in regards to offsite consequences. The results of the two pathways were combined to prioritize gaps in current capabilities.

  5. Measurement and calculations of long-lived radionuclide activity forming in the fast neutron field in some ITER construction steels

    Energy Technology Data Exchange (ETDEWEB)

    Pohorecki, W., E-mail: poho@agh.edu.pl [AGH University of Science and Technology, Faculty of Energy and Fuels, Al. Mickiewicza 30, 30-059 Krakow (Poland); Jodłowski, P. [AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Al. Mickiewicza 30, 30-059 Krakow (Poland); Pytel, K.; Prokopowicz, R. [National Centre for Nuclear Research, ul. Sołtana 7, 05-400 Otwock-Świerk (Poland)

    2014-10-15

    Highlights: • Measurement and calculations of long-lived gamma-emitting radionuclide activity forming in the fission reactor fast neutron field were done, in some ITER construction steels. • The neutron flux density was measured by means of activation foil method and unfolding technique. • Activity calculations were done by means of FISPACT-II code using the activation libraries EAF-2010 and TALYS-2011. • The activity measurements were done by means of gamma-ray spectrometry. - Abstract: Measurement and calculations of long-lived gamma-emitting radionuclide activity forming in the fission reactor fast neutron field were done, for some ITER construction steels. The activation was conducted in fast neutron irradiation channel of the MARIA research fission reactor (Poland). The dimensions of steel samples were 10 mm × 10 mm × 1 mm and mass was approximately 0.8 g. The neutron flux density was measured by means of activation foil method and unfolding technique; fraction of neutrons above 1 keV was 95%. The activation lasted 242 h and cooling took 100 days; the mean neutron flux density was 2.9E12 n/(cm{sup 2} s) (neutrons above 500 keV are 53% of total) whereas total fluency 2.53E18 cm{sup −2}. The activity measurements were done by means of gamma-ray spectrometry. Activity calculations were done by means of FISPACT-II code using the activation libraries EAF-2010 and TENDL-2011 and experimentally determined neutron flux. Measured activity of long-lived gamma emitting radionuclides was, in average, about 6.3 MBq/g 100 days after activation; the dominant radionuclides were {sup 58}Co and {sup 54}Mn (about 81% and 14% of total activity respectively). The C/E ratio differs for particular radionuclides and is in the range 0.86–0.92 for {sup 51}Cr, 0.93–1.21 for {sup 54}Mn, 0.77–0.98 for {sup 57}Co, 0.91–1.21 for {sup 58}Co, 1.17–1.27 for {sup 59}Fe, and 1.75–2.44 for {sup 60}Co.

  6. Polarizable Simulations with Second order Interaction Model – force field and software for fast polarizable calculations: Parameters for small model systems and free energy calculations

    Science.gov (United States)

    Kaminski, George A.; Ponomarev, Sergei Y.; Liu, Aibing B.

    2009-01-01

    We are presenting POSSIM (POlarizable Simulations with Second order Interaction Model) – a software package and a set of parameters designed for molecular simulations. The key feature of POSSIM is that the electrostatic polarization is taken into account using a previously introduced fast formalism. This permits cutting computational cost of using the explicit polarization by about an order of magnitude. In this article, parameters for water, methane, ethane, propane, butane, methanol and NMA are introduced. These molecules are viewed as model systems for protein simulations. We have achieved our goal of ca. 0.5 kcal/mol accuracy for gas-phase dimerization energies and no more than 2% deviations in liquid state heats of vaporization and densities. Moreover, free energies of hydration of the polarizable methane, ethane and methanol have been calculated using the statistical perturbation theory. These calculations are a model for calculating protein pKa shifts and ligand binding affinities. The free energies of hydration were found to be 2.12 kcal/mol, 1.80 kcal/mol and −4.95 kcal/mol for methane, ethane and methanol, respectively. The experimentally determined literature values are 1.91 kcal/mol, 1.83 kcal/mol and −5.11 kcal/mol. The POSSIM average error in these absolute free energies of hydration is only about 0.13 kcal/mol. Using the statistical perturbation theory with polarizable force fields is not widespread, and we believe that this work opens road to further development of the POSSIM force field and its applications for obtaining accurate energies in protein-related computer modeling. PMID:20209038

  7. QuickPol: Fast effective beam matrices calculation for CMB polarization

    CERN Document Server

    Hivon, Eric; Ponthieu, Nicolas

    2016-01-01

    Current and planned observations of the Cosmic Microwave Background (CMB) polarization anisotropies, with their ever increasing number of detectors, have reached a potential accuracy that requires a very demanding control of systematic effects. While some of these systematics can be reduced in the design of the instruments, others will be have to be modeled and hopefully accounted for or corrected a posteriori. We propose QuickPol, a quick and accurate calculation of the full effective beam transfer function and of temperature to polarization leakage at the power spectra level, as induced by beam imperfections and mismatches between detector optical and electronic responses. All the observation details such as exact scanning strategy, imperfect polarization measurements and flagged samples are accounted for. Our results are validated on Planck-HFI simulations. We show how the pipeline can be used to propagate instrumental uncertainties up to the final science products, and could be applied to experiments with...

  8. Fast 3D dosimetric verifications based on an electronic portal imaging device using a GPU calculation engine.

    Science.gov (United States)

    Zhu, Jinhan; Chen, Lixin; Chen, Along; Luo, Guangwen; Deng, Xiaowu; Liu, Xiaowei

    2015-04-11

    To use a graphic processing unit (GPU) calculation engine to implement a fast 3D pre-treatment dosimetric verification procedure based on an electronic portal imaging device (EPID). The GPU algorithm includes the deconvolution and convolution method for the fluence-map calculations, the collapsed-cone convolution/superposition (CCCS) algorithm for the 3D dose calculations and the 3D gamma evaluation calculations. The results of the GPU-based CCCS algorithm were compared to those of Monte Carlo simulations. The planned and EPID-based reconstructed dose distributions in overridden-to-water phantoms and the original patients were compared for 6 MV and 10 MV photon beams in intensity-modulated radiation therapy (IMRT) treatment plans based on dose differences and gamma analysis. The total single-field dose computation time was less than 8 s, and the gamma evaluation for a 0.1-cm grid resolution was completed in approximately 1 s. The results of the GPU-based CCCS algorithm exhibited good agreement with those of the Monte Carlo simulations. The gamma analysis indicated good agreement between the planned and reconstructed dose distributions for the treatment plans. For the target volume, the differences in the mean dose were less than 1.8%, and the differences in the maximum dose were less than 2.5%. For the critical organs, minor differences were observed between the reconstructed and planned doses. The GPU calculation engine was used to boost the speed of 3D dose and gamma evaluation calculations, thus offering the possibility of true real-time 3D dosimetric verification.

  9. Fast and Accurate Radiative Transfer Calculations Using Principal Component Analysis for (Exo-)Planetary Retrieval Models

    Science.gov (United States)

    Kopparla, P.; Natraj, V.; Shia, R. L.; Spurr, R. J. D.; Crisp, D.; Yung, Y. L.

    2015-12-01

    Radiative transfer (RT) computations form the engine of atmospheric retrieval codes. However, full treatment of RT processes is computationally expensive, prompting usage of two-stream approximations in current exoplanetary atmospheric retrieval codes [Line et al., 2013]. Natraj et al. [2005, 2010] and Spurr and Natraj [2013] demonstrated the ability of a technique using principal component analysis (PCA) to speed up RT computations. In the PCA method for RT performance enhancement, empirical orthogonal functions are developed for binned sets of inherent optical properties that possess some redundancy; costly multiple-scattering RT calculations are only done for those few optical states corresponding to the most important principal components, and correction factors are applied to approximate radiation fields. Kopparla et al. [2015, in preparation] extended the PCA method to a broadband spectral region from the ultraviolet to the shortwave infrared (0.3-3 micron), accounting for major gas absorptions in this region. Here, we apply the PCA method to a some typical (exo-)planetary retrieval problems. Comparisons between the new model, called Universal Principal Component Analysis Radiative Transfer (UPCART) model, two-stream models and line-by-line RT models are performed, for spectral radiances, spectral fluxes and broadband fluxes. Each of these are calculated at the top of the atmosphere for several scenarios with varying aerosol types, extinction and scattering optical depth profiles, and stellar and viewing geometries. We demonstrate that very accurate radiance and flux estimates can be obtained, with better than 1% accuracy in all spectral regions and better than 0.1% in most cases, as compared to a numerically exact line-by-line RT model. The accuracy is enhanced when the results are convolved to typical instrument resolutions. The operational speed and accuracy of UPCART can be further improved by optimizing binning schemes and parallelizing the codes, work

  10. A computer code to calculate the fast induced signals by electron swarms in gases

    Energy Technology Data Exchange (ETDEWEB)

    Tobias, Carmen C.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Mangiarotti, Alessio [Universidade de Coimbra (Portugal). Dept. de Fisica. Lab. de Instrumentacao e Fisica Experimental de Particulas

    2010-07-01

    Full text: The study of electron transport parameters (i.e. drift velocity, diffusion coefficients and first Townsend coefficient) in gases is very important in several areas of applied nuclear science. For example, they are a relevant input to the design of particle detector employing micro-structures (MSGC's, micromegas, GEM's) and RPC's (resistive plate chambers). Moreover, if the data are accurate and complete enough, they can be used to derive a set of electron impact cross-sections with their energy dependence, that are a key ingredient in micro-dosimetry calculations. Despite the fundamental need of such data and the long age of the field, the gases of possible interest are so many and the effort of obtaining good quality data so time demanding, that an important contribution can still be made. As an example, electrons drift velocity at moderate field strengths (up to 50 Td) in pure Isobutane (a tissue equivalent gas) has been measured only recently by the IPEN-LIP collaboration using a dedicated setup. The transport parameters are derived from the recorded electric pulse induced by a swarm started with a pulsed laser shining on the cathode. To aid the data analysis, a special code has been developed to calculate the induced pulse by solving the electrons continuity equation including growth, drift and diffusion. A realistic profile of the initial laser beam is taken into account as well as the boundary conditions at the cathode and anode. The approach is either semi-analytic, based on the expression derived by P. H. Purdie and J. Fletcher, or fully numerical, using a finite difference scheme improved over the one introduced by J. de Urquijo et al. The agreement between the two will be demonstrated under typical conditions for the mentioned experimental setup. A brief discussion on the stability of the finite difference scheme will be given. The new finite difference scheme allows a detailed investigation of the importance of back diffusion to

  11. Evaluation of PENFAST - A fast Monte Carlo code for dose calculations in photon and electron radiotherapy treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Habib, B.; Poumarede, B.; Tola, F.; Barthe, J. [CEA, LIST, Dept Technol Capteur et Signal, F-91191 Gif Sur Yvette, (France)

    2010-07-01

    The aim of the present study is to demonstrate the potential of accelerated dose calculations, using the fast Monte Carlo (MC) code referred to as PENFAST, rather than the conventional MC code PENELOPE, without losing accuracy in the computed dose. For this purpose, experimental measurements of dose distributions in homogeneous and inhomogeneous phantoms were compared with simulated results using both PENELOPE and PENFAST. The simulations and experiments were performed using a Saturne 43 linac operated at 12 MV (photons), and at 18 MeV (electrons). Pre-calculated phase space files (PSFs) were used as input data to both the PENELOPE and PENFAST dose simulations. Since depth-dose and dose profile comparisons between simulations and measurements in water were found to be in good agreement (within {+-} 1% to 1 mm), the PSF calculation is considered to have been validated. In addition, measured dose distributions were compared to simulated results in a set of clinically relevant, inhomogeneous phantoms, consisting of lung and bone heterogeneities in a water tank. In general, the PENFAST results agree to within a 1% to 1 mm difference with those produced by PENELOPE, and to within a 2% to 2 mm difference with measured values. Our study thus provides a pre-clinical validation of the PENFAST code. It also demonstrates that PENFAST provides accurate results for both photon and electron beams, equivalent to those obtained with PENELOPE. CPU time comparisons between both MC codes show that PENFAST is generally about 9-21 times faster than PENELOPE. (authors)

  12. A Hybrid Algorithm of Fast Invariant Imbedding and Doubling-Adding Methods for Efficient Multiple Scattering Calculations

    CERN Document Server

    Kawabata, Kiyoshi

    2016-01-01

    An efficient hybrid numerical method for multiple scattering calculations is proposed. We use the well established doubling--adding method to find the reflection function of the lowermost homogeneous slab comprising the atmosphere of our interest. This reflection function provides the initial value for the fast invariant imbedding method of Sato et al., (1977), with which layers are added until the final reflection function of the entire atmosphere is obtained. The execution speed of this hybrid method is no slower than one half of that of the doubling-adding method, probably the fastest algorithm available, even in the most unsuitable cases for the fast invariant imbedding method. The efficiency of the proposed method increases rapidly with the number of atmospheric slabs and the optical thickness of each slab. For some cases, its execution speed is approximately four times faster than the doubling--adding method. This work has been published in NAIS Journal (ISSN 1882-9392) Vol. 7, 5-16 (2012).

  13. Time-dependent calculations of transfer ionization by fast proton-helium collision in one-dimensional kinematics

    Science.gov (United States)

    Serov, Vladislav V.; Kheifets, A. S.

    2014-12-01

    We analyze a transfer ionization (TI) reaction in the fast proton-helium collision H++He →H0+He2 ++ e- by solving a time-dependent Schrödinger equation (TDSE) under the classical projectile motion approximation in one-dimensional kinematics. In addition, we construct various time-independent analogs of our model using lowest-order perturbation theory in the form of the Born series. By comparing various aspects of the TDSE and the Born series calculations, we conclude that the recent discrepancies of experimental and theoretical data may be attributed to deficiency of the Born models used by other authors. We demonstrate that the correct Born series for TI should include the momentum-space overlap between the double-ionization amplitude and the wave function of the transferred electron.

  14. Time-dependent calculations of transfer ionization by fast proton-helium collision in one-dimensional kinematics

    CERN Document Server

    Serov, Vladislav V

    2014-01-01

    We analyze a transfer ionization (TI) reaction in the fast proton-helium collision $\\rm H^+ + He \\to H^0 + He^{2+} + e^-$ by solving a time-dependent Schr\\"odinger equation (TDSE) under the classical projectile motion approximation in one-dimensional kinematics. In addition, we construct various time independent analogues of our model using lowest order perturbation theory in the form of the Born series. By comparing various aspects of the TDSE and the Born series calculations, we conclude that the recent discrepancies of experimental and theoretical data may be attributed to deficiency of the Born models used by other authors. We demonstrate that the correct Born series for TI should include the momentum space overlap between the double ionization amplitude and the wave function of the transferred electron.

  15. Fast patient-specific Monte Carlo brachytherapy dose calculations via the correlated sampling variance reduction technique

    Energy Technology Data Exchange (ETDEWEB)

    Sampson, Andrew; Le Yi; Williamson, Jeffrey F. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States)

    2012-02-15

    Purpose: To demonstrate potential of correlated sampling Monte Carlo (CMC) simulation to improve the calculation efficiency for permanent seed brachytherapy (PSB) implants without loss of accuracy. Methods: CMC was implemented within an in-house MC code family (PTRAN) and used to compute 3D dose distributions for two patient cases: a clinical PSB postimplant prostate CT imaging study and a simulated post lumpectomy breast PSB implant planned on a screening dedicated breast cone-beam CT patient exam. CMC tallies the dose difference, {Delta}D, between highly correlated histories in homogeneous and heterogeneous geometries. The heterogeneous geometry histories were derived from photon collisions sampled in a geometrically identical but purely homogeneous medium geometry, by altering their particle weights to correct for bias. The prostate case consisted of 78 Model-6711 {sup 125}I seeds. The breast case consisted of 87 Model-200 {sup 103}Pd seeds embedded around a simulated lumpectomy cavity. Systematic and random errors in CMC were unfolded using low-uncertainty uncorrelated MC (UMC) as the benchmark. CMC efficiency gains, relative to UMC, were computed for all voxels, and the mean was classified in regions that received minimum doses greater than 20%, 50%, and 90% of D{sub 90}, as well as for various anatomical regions. Results: Systematic errors in CMC relative to UMC were less than 0.6% for 99% of the voxels and 0.04% for 100% of the voxels for the prostate and breast cases, respectively. For a 1 x 1 x 1 mm{sup 3} dose grid, efficiency gains were realized in all structures with 38.1- and 59.8-fold average gains within the prostate and breast clinical target volumes (CTVs), respectively. Greater than 99% of the voxels within the prostate and breast CTVs experienced an efficiency gain. Additionally, it was shown that efficiency losses were confined to low dose regions while the largest gains were located where little difference exists between the homogeneous and

  16. An improved fast multipole method for electrostatic potential calculations in a class of coarse-grained molecular simulations

    Energy Technology Data Exchange (ETDEWEB)

    Poursina, Mohammad [Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ 85721 (United States); Anderson, Kurt S. [Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute (RPI), Troy, NY 12180 (United States)

    2014-08-01

    This paper presents a novel algorithm to approximate the long-range electrostatic potential field in the Cartesian coordinates applicable to 3D coarse-grained simulations of biopolymers. In such models, coarse-grained clusters are formed via treating groups of atoms as rigid and/or flexible bodies connected together via kinematic joints. Therefore, multibody dynamic techniques are used to form and solve the equations of motion of such coarse-grained systems. In this article, the approximations for the potential fields due to the interaction between a highly negatively/positively charged pseudo-atom and charged particles, as well as the interaction between clusters of charged particles, are presented. These approximations are expressed in terms of physical and geometrical properties of the bodies such as the entire charge, the location of the center of charge, and the pseudo-inertia tensor about the center of charge of the clusters. Further, a novel substructuring scheme is introduced to implement the presented far-field potential evaluations in a binary tree framework as opposed to the existing quadtree and octree strategies of implementing fast multipole method. Using the presented Lagrangian grids, the electrostatic potential is recursively calculated via sweeping two passes: assembly and disassembly. In the assembly pass, adjacent charged bodies are combined together to form new clusters. Then, the potential field of each cluster due to its interaction with faraway resulting clusters is recursively calculated in the disassembly pass. The method is highly compatible with multibody dynamic schemes to model coarse-grained biopolymers. Since the proposed method takes advantage of constant physical and geometrical properties of rigid clusters, improvement in the overall computational cost is observed comparing to the tradition application of fast multipole method.

  17. Genetically elevated non-fasting triglycerides and calculated remnant cholesterol as causal risk factors for myocardial infarction.

    Science.gov (United States)

    Jørgensen, Anders Berg; Frikke-Schmidt, Ruth; West, Anders Sode; Grande, Peer; Nordestgaard, Børge G; Tybjærg-Hansen, Anne

    2013-06-01

    Elevated non-fasting triglycerides mark elevated levels of remnant cholesterol. Using a Mendelian randomization approach, we tested whether genetically increased remnant cholesterol in hypertriglyceridaemia due to genetic variation in the apolipoprotein A5 gene (APOA5) associates with an increased risk of myocardial infarction (MI). We resequenced the core promoter and coding regions of APOA5 in individuals with the lowest 1% (n = 95) and highest 2% (n = 190) triglyceride levels in the Copenhagen City Heart Study (CCHS, n = 10 391). Genetic variants which differed in frequency between the two extreme triglyceride groups (c.-1131T > C, S19W, and c.*31C > T; P-value: 0.06 to triglyceride levels, were genotyped in the Copenhagen General Population Study (CGPS), the CCHS, and the Copenhagen Ischemic Heart Disease Study (CIHDS), comprising a total of 5705 MI cases and 54 408 controls. Genotype combinations of these common variants associated with increases in non-fasting triglycerides and calculated remnant cholesterol of, respectively, up to 68% (1.10 mmol/L) and 56% (0.40 mmol/L) (P triglycerides was 1.57 (1.32-2.68) compared with a causal genetic odds ratio of 1.94 (1.40-1.85) (P for comparison = 0.28). For calculated remnant cholesterol, the corresponding values were 1.67(1.38-2.02) observational and 2.23(1.48-3.35) causal (P for comparison = 0.21). These data are consistent with a causal association between elevated levels of remnant cholesterol in hypertriglyceridaemia and an increased risk of MI. Limitations include that remnants were not measured directly, and that APOA5 genetic variants may influence other lipoprotein parameters.

  18. Travel time calculation in regular 3D grid in local and regional scale using fast marching method

    Science.gov (United States)

    Polkowski, M.

    2015-12-01

    Local and regional 3D seismic velocity models of crust and sediments are very important for numerous technics like mantle and core tomography, localization of local and regional events and others. Most of those techniques require calculation of wave travel time through the 3D model. This can be achieved using multiple approaches from simple ray tracing to advanced full waveform calculation. In this study simple and efficient implementation of fast marching method is presented. This method provides more information than ray tracing and is much less complicated than methods like full waveform being the perfect compromise. Presented code is written in C++, well commented and is easy to modify for different types of studies. Additionally performance is widely discussed including possibilities of multithreading and massive parallelism like GPU. Source code will be published in 2016 as it is part of the PhD thesis. National Science Centre Poland provided financial support for this work via NCN grant DEC-2011/02/A/ST10/00284.

  19. Fast and scalable prediction of local energy at grain boundaries: machine-learning based modeling of first-principles calculations

    Science.gov (United States)

    Tamura, Tomoyuki; Karasuyama, Masayuki; Kobayashi, Ryo; Arakawa, Ryuichi; Shiihara, Yoshinori; Takeuchi, Ichiro

    2017-10-01

    We propose a new scheme based on machine learning for the efficient screening in grain-boundary (GB) engineering. A set of results obtained from first-principles calculations based on density functional theory (DFT) for a small number of GB systems is used as a training data set. In our scheme, by partitioning the total energy into atomic energies using a local-energy analysis scheme, we can increase the training data set significantly. We use atomic radial distribution functions and additional structural features as atom descriptors to predict atomic energies and GB energies simultaneously using the least absolute shrinkage and selection operator, which is a recent standard regression technique in statistical machine learning. In the test study with fcc-Al [110] symmetric tilt GBs, we could achieve enough predictive accuracy to understand energy changes at and near GBs at a glance, even if we collected training data from only 10 GB systems. The present scheme can emulate time-consuming DFT calculations for large GB systems with negligible computational costs, and thus enable the fast screening of possible alternative GB systems.

  20. RegPT: Direct and fast calculation of regularized cosmological power spectrum at two-loop order

    CERN Document Server

    Taruya, Atsushi; Nishimichi, Takahiro; Codis, Sandrine

    2012-01-01

    We present a specific prescription for the calculation of cosmological power spectra, exploited here at two-loop order in perturbation theory (PT), based on the multi-point propagator expansion. In this approach power spectra are constructed from the regularized expressions of the propagators that reproduce both the resummed behavior in the high-k limit and the standard PT results at low-k. With the help of N-body simulations, we show that such a construction gives robust and accurate predictions for both the density power spectrum and the correlation function at percent-level in the weakly non-linear regime. We then present an algorithm that allows accelerated evaluations of all the required diagrams by reducing the computational tasks to one-dimensional integrals. This is achieved by means of pre-computed kernel sets defined for appropriately chosen fiducial models. The computational time for two-loop results is then reduced from a few minutes, with the direct method, to a few seconds with the fast one. The...

  1. Evaluation of observable phase space by fast ion loss detector by calculating particle orbits in consideration of plasma facing components and three dimensional magnetic field

    Science.gov (United States)

    Shinohara, Kouji; Kim, Junghee; Kim, Jun Young; Rhee, Tongnyeol

    2016-11-01

    The orbits of lost ions can be calculated from the information obtained by a fast ion loss detector (FILD). The orbits suggest a source of the lost fast ions in a phase space. However, it is not obvious whether an observable set of orbits, or phase space, of a FILD appropriately covers the region of interest to be investigated since the observable phase space can be affected by plasma facing components (PFCs) and a magnetic configuration. A tool has been developed to evaluate the observable phase space of FILD diagnostic by calculating particle orbits by taking the PFCs and 3D magnetic field into account.

  2. Forward Field Autotransfusion Device

    Science.gov (United States)

    1985-05-10

    thoracostomy tube 13 connected to a collapsible bulb, or suction pump. Within the pump, and 14 connected to the thoracostomy tube, is a one-way flutter... thoracostomy tube, an open end of which (not 15 shown in the drawing) is inserted through an incision 11 in chest 12 in 16 order to penetrate the

  3. A (fast) 'precipiton' method to calculate river hydrodynamics with applications to landscape evolution models as well as flood prediction

    Science.gov (United States)

    Davy, P.

    2013-12-01

    Particle-based methods have been popular to develop models of landscape evolution able to reproduce complex features such as dynamical braided patterns. Such a high-resolution high-frequency geomorphical structures are beyond the scope of simple landscape evolution model, whose hydrodynamics description is much too rudimentary, and hardly modeled with sophisticated CFD models because of computational time. Solving hydrodynamics remains however a major issue for the particle-based models, which may cast doubt on the relevance of the modeled dynamics. The 'precipiton' method consists in routing elementary water volumes (i.e. precipitons) on top of topography with erosive and deposition actions. The basic method assumes that precipitons move down the steepest descent slope of topography, which is a very crude approximation of the river hydrodynamics. Here we present an original way to calculate both river depth and velocity, from a method that remains intimately embedded into the precipiton framework. The method consists in solving water depth from a differential equation where the water depth is increased by a constant (small) quantity at each precipiton passage, and decreased by a mass balance 1st-order differential equation, where the flux is related to water depth from a Manning-type flow resistance equation. The precipiton are then routed on top of the water surface so calculated, towards lowest zones. The method is applicable even if the precipitons are routed one by one, i.e. independently of each others. It is not subject to the classical drying-wetting issue. The method has been applied to a large number of geomorphic cases including lake filling, circular channels, flow over topographic bumps, flow over vegetation patches and river banks, dam gate, or real cases with high resolution LIDAR topography. In all cases, the method is very fast to find a solution for water depths, which fits the shallow water solution without inertia. For real topographies, the

  4. Calculations to compare different ways of modelling the plate geometry cells of the Zebra fast critical assembly, MZA

    Energy Technology Data Exchange (ETDEWEB)

    Rowlands, John, E-mail: rowlandsjl@aol.com

    2009-03-15

    The core region cells of the Zebra fast critical assembly MZA comprise 14 plates in a square steel tube, with 12 cells being stacked axially to form the core section of the assembly. The cells can be modelled in different levels of detail, ranging from a three-dimensional representation in which the core (The word core is used to describe both the region of a plate containing the main material, such as plutonium, UO{sub 2} or sodium, and the region of the assembly containing fissile material cells.) and canning regions of the plates and the void gaps between the edges of the plates and the steel tube, and between tubes, are represented. Simplified models include a three-dimensional representation in which the void regions are combined with the tube material. A further simplified three-dimensional model, called the MURAL model, represents the core regions of the plates but homogenises the canning, tube material and void regions. Two types of one-dimensional slab geometry model are found in the literature, one in which the materials are homogenised within each of the three axial slab regions of a canned plate (plate core and upper and lower canning regions) and a further simplified version in which the plate is modelled as a single region, the compositions being averaged over the whole thickness of the plate, comprising the plate core material, the canning and the tube material. MONK Monte Carlo calculations have been made for each of these models, and also for the fully homogenised cells, and the k-effective values, core sodium void reactivities and reaction rate ratios are compared.

  5. Quantum molecular mechanics-a noniterative procedure for the fast ab Initio calculation of closed shell systems.

    Science.gov (United States)

    Moura, Gustavo L C; Simas, Alfredo M

    2012-04-05

    In this article, we advance the foundations of a strategy to develop a molecular mechanics method based not on classical mechanics and force fields but entirely on quantum mechanics and localized electron-pair orbitals, which we call quantum molecular mechanics (QMM). Accordingly, we introduce a new manner of calculating Hartree-Fock ab initio wavefunctions of closed shell systems based on variationally preoptimized nonorthogonal electron pair orbitals constructed by linear combinations of basis functions centered on the atoms. QMM is noniterative and requires only one extremely fast inversion of a single sparse matrix to arrive to the one-particle density matrix, to the electron density, and consequently, to the ab initio electrostatic potential around the molecular system, or cluster of molecules. Although QMM neglects the smaller polarization effects due to intermolecular interactions, it fully takes into consideration polarization effects due to the much stronger intramolecular geometry distortions. For the case of methane, we show that QMM was able to reproduce satisfactorily the energetics and polarization effects of all distortions of the molecule along the nine normal modes of vibration, well beyond the harmonic region. We present the first practical applications of the QMM method by examining, in detail, the cases of clusters of helium atoms, hydrogen molecules, methane molecules, as well as one molecule of HeH(+) surrounded by several methane molecules. We finally advance and discuss the potentialities of an exact formula to compute the QMM total energy, in which only two center integrals are involved, provided that the fully optimized electron-pair orbitals are known.

  6. SU-E-T-423: Fast Photon Convolution Calculation with a 3D-Ideal Kernel On the GPU

    Energy Technology Data Exchange (ETDEWEB)

    Moriya, S; Sato, M [Komazawa University, Setagaya, Tokyo (Japan); Tachibana, H [National Cancer Center Hospital East, Kashiwa, Chiba (Japan)

    2015-06-15

    Purpose: The calculation time is a trade-off for improving the accuracy of convolution dose calculation with fine calculation spacing of the KERMA kernel. We investigated to accelerate the convolution calculation using an ideal kernel on the Graphic Processing Units (GPU). Methods: The calculation was performed on the AMD graphics hardware of Dual FirePro D700 and our algorithm was implemented using the Aparapi that convert Java bytecode to OpenCL. The process of dose calculation was separated with the TERMA and KERMA steps. The dose deposited at the coordinate (x, y, z) was determined in the process. In the dose calculation running on the central processing unit (CPU) of Intel Xeon E5, the calculation loops were performed for all calculation points. On the GPU computation, all of the calculation processes for the points were sent to the GPU and the multi-thread computation was done. In this study, the dose calculation was performed in a water equivalent homogeneous phantom with 150{sup 3} voxels (2 mm calculation grid) and the calculation speed on the GPU to that on the CPU and the accuracy of PDD were compared. Results: The calculation time for the GPU and the CPU were 3.3 sec and 4.4 hour, respectively. The calculation speed for the GPU was 4800 times faster than that for the CPU. The PDD curve for the GPU was perfectly matched to that for the CPU. Conclusion: The convolution calculation with the ideal kernel on the GPU was clinically acceptable for time and may be more accurate in an inhomogeneous region. Intensity modulated arc therapy needs dose calculations for different gantry angles at many control points. Thus, it would be more practical that the kernel uses a coarse spacing technique if the calculation is faster while keeping the similar accuracy to a current treatment planning system.

  7. pySeismicFMM: Python based travel time calculation in regular 2D and 3D grids in Cartesian and geographic coordinates using Fast Marching Method

    Science.gov (United States)

    Polkowski, Marcin

    2016-04-01

    Seismic wave travel time calculation is the most common numerical operation in seismology. The most efficient is travel time calculation in 1D velocity model - for given source, receiver depths and angular distance time is calculated within fraction of a second. Unfortunately, in most cases 1D is not enough to encounter differentiating local and regional structures. Whenever possible travel time through 3D velocity model has to be calculated. It can be achieved using ray calculation or time propagation in space. While single ray path calculation is quick it is complicated to find the ray path that connects source with the receiver. Time propagation in space using Fast Marching Method seems more efficient in most cases, especially when there are multiple receivers. In this presentation a Python module pySeismicFMM is presented - simple and very efficient tool for calculating travel time from sources to receivers. Calculation requires regular 2D or 3D velocity grid either in Cartesian or geographic coordinates. On desktop class computer calculation speed is 200k grid cells per second. Calculation has to be performed once for every source location and provides travel time to all receivers. pySeismicFMM is free and open source. Development of this tool is a part of authors PhD thesis. National Science Centre Poland provided financial support for this work via NCN grant DEC-2011/02/A/ST10/00284.

  8. FAST-PT II: an algorithm to calculate convolution integrals of general tensor quantities in cosmological perturbation theory

    Science.gov (United States)

    Fang, Xiao; Blazek, Jonathan A.; McEwen, Joseph E.; Hirata, Christopher M.

    2017-02-01

    Cosmological perturbation theory is a powerful tool to predict the statistics of large-scale structure in the weakly non-linear regime, but even at 1-loop order it results in computationally expensive mode-coupling integrals. Here we present a fast algorithm for computing 1-loop power spectra of quantities that depend on the observer's orientation, thereby generalizing the FAST-PT framework (McEwen et al., 2016) that was originally developed for scalars such as the matter density. This algorithm works for an arbitrary input power spectrum and substantially reduces the time required for numerical evaluation. We apply the algorithm to four examples: intrinsic alignments of galaxies in the tidal torque model; the Ostriker-Vishniac effect; the secondary CMB polarization due to baryon flows; and the 1-loop matter power spectrum in redshift space. Code implementing this algorithm and these applications is publicly available at https://github.com/JoeMcEwen/FAST-PT.

  9. FAST-PT II: an algorithm to calculate convolution integrals of general tensor quantities in cosmological perturbation theory

    CERN Document Server

    Fang, Xiao; McEwen, Joseph E; Hirata, Christopher M

    2016-01-01

    Cosmological perturbation theory is a powerful tool to predict the statistics of large-scale structure in the weakly non-linear regime, but even at 1-loop order it results in computationally expensive mode-coupling integrals. Here we present a fast algorithm for computing 1-loop power spectra of quantities that depend on the observer's orientation, thereby generalizing the FAST-PT framework (McEwen et al., 2016) that was originally developed for scalars such as the matter density. This algorithm works for an arbitrary input power spectrum and substantially reduces the time required for numerical evaluation. We apply the algorithm to four examples: intrinsic alignments of galaxies in the tidal torque model; the Ostriker-Vishniac effect; the secondary CMB polarization due to baryon flows; and the 1-loop matter power spectrum in redshift space. Code implementing this algorithm and these applications is publicly available at https://github.com/JoeMcEwen/FAST-PT.

  10. Genetically elevated non-fasting triglycerides and calculated remnant cholesterol as causal risk factors for myocardial infarction

    DEFF Research Database (Denmark)

    Jørgensen, Anders Berg; Frikke-Schmidt, Ruth; West, Anders Sode

    2012-01-01

    AimsElevated non-fasting triglycerides mark elevated levels of remnant cholesterol. Using a Mendelian randomization approach, we tested whether genetically increased remnant cholesterol in hypertriglyceridaemia due to genetic variation in the apolipoprotein A5 gene (APOA5) associates with an incr...

  11. Effects of Fission Yield Data in the Calculation of Antineutrino Spectra for 235U (n ,fission) at Thermal and Fast Neutron Energies

    Science.gov (United States)

    Sonzogni, A. A.; McCutchan, E. A.; Johnson, T. D.; Dimitriou, P.

    2016-04-01

    Fission yields form an integral part of the prediction of antineutrino spectra generated by nuclear reactors, but little attention has been paid to the quality and reliability of the data used in current calculations. Following a critical review of the thermal and fast ENDF/B-VII.1 235U 235 fission yields, deficiencies are identified and improved yields are obtained, based on corrections of erroneous yields, consistency between decay and fission yield data, and updated isomeric ratios. These corrected yields are used to calculate antineutrino spectra using the summation method. An anomalous value for the thermal fission yield of 86Ge generates an excess of antineutrinos at 5-7 MeV, a feature which is no longer present when the corrected yields are used. Thermal spectra calculated with two distinct fission yield libraries (corrected ENDF/B and JEFF) differ by up to 6% in the 0-7 MeV energy window, allowing for a basic estimate of the uncertainty involved in the fission yield component of summation calculations. Finally, the fast neutron antineutrino spectrum is calculated, which at the moment can only be obtained with the summation method and may be relevant for short baseline reactor experiments using highly enriched uranium fuel.

  12. Effects of Fission Yield Data in the Calculation of Antineutrino Spectra for ^{235}U(n,fission) at Thermal and Fast Neutron Energies.

    Science.gov (United States)

    Sonzogni, A A; McCutchan, E A; Johnson, T D; Dimitriou, P

    2016-04-01

    Fission yields form an integral part of the prediction of antineutrino spectra generated by nuclear reactors, but little attention has been paid to the quality and reliability of the data used in current calculations. Following a critical review of the thermal and fast ENDF/B-VII.1 ^{235}U fission yields, deficiencies are identified and improved yields are obtained, based on corrections of erroneous yields, consistency between decay and fission yield data, and updated isomeric ratios. These corrected yields are used to calculate antineutrino spectra using the summation method. An anomalous value for the thermal fission yield of ^{86}Ge generates an excess of antineutrinos at 5-7 MeV, a feature which is no longer present when the corrected yields are used. Thermal spectra calculated with two distinct fission yield libraries (corrected ENDF/B and JEFF) differ by up to 6% in the 0-7 MeV energy window, allowing for a basic estimate of the uncertainty involved in the fission yield component of summation calculations. Finally, the fast neutron antineutrino spectrum is calculated, which at the moment can only be obtained with the summation method and may be relevant for short baseline reactor experiments using highly enriched uranium fuel.

  13. An open source MATLAB program for fast numerical Feynman integral calculations for open quantum system dynamics on GPUs

    CERN Document Server

    Dattani, Nikesh S

    2012-01-01

    This MATLAB program calculates the dynamics of the reduced density matrix of an open quantum system modeled by the Feynman-Vernon model. The user gives the program a vector describing the coordinate of an open quantum system, a hamiltonian matrix describing its energy, and a spectral distribution function and temperature describing the environment's influence on it, in addition to the open quantum system's intial density matrix and a grid of times. With this, the program returns the reduced density matrix of the open quantum system at all (or some) moments specified by that grid of times. This overall calculation can be divided into two stages: the setup of the Feynman integral, and the actual calculation of the Feynman integral for time-propagation of the density matrix. When this program calculates this propagation on a multi-core CPU, it is this propagation that is usually the rate limiting step of the calculation, but when it is calculated on a GPU, the propagation is calculated so quickly that the setup ...

  14. Fast and precise algorithms for calculating offset correction in single photon counting ASICs built in deep sub-micron technologies

    Science.gov (United States)

    Maj, P.

    2014-07-01

    An important trend in the design of readout electronics working in the single photon counting mode for hybrid pixel detectors is to minimize the single pixel area without sacrificing its functionality. This is the reason why many digital and analog blocks are made with the smallest, or next to smallest, transistors possible. This causes a problem with matching among the whole pixel matrix which is acceptable by designers and, of course, it should be corrected with the use of dedicated circuitry, which, by the same rule of minimizing devices, suffers from the mismatch. Therefore, the output of such a correction circuit, controlled by an ultra-small area DAC, is not only a non-linear function, but it is also often non-monotonic. As long as it can be used for proper correction of the DC operation points inside each pixel, it is acceptable, but the time required for correction plays an important role for both chip verification and the design of a big, multi-chip system. Therefore, we present two algorithms: a precise one and a fast one. The first algorithm is based on the noise hits profiles obtained during so called threshold scan procedures. The fast correction procedure is based on the trim DACs scan and it takes less than a minute in a SPC detector systems consisting of several thousands of pixels.

  15. A Fast Method to Calculate the Spatial Impulse Response for 1-D Linear Ultrasonic Phased Array Transducers.

    Science.gov (United States)

    Zou, Cheng; Sun, Zhenguo; Cai, Dong; Muhammad, Salman; Zhang, Wenzeng; Chen, Qiang

    2016-11-08

    A method is developed to accurately determine the spatial impulse response at the specifically discretized observation points in the radiated field of 1-D linear ultrasonic phased array transducers with great efficiency. In contrast, the previously adopted solutions only optimize the calculation procedure for a single rectangular transducer and required approximation considerations or nonlinear calculation. In this research, an algorithm that follows an alternative approach to expedite the calculation of the spatial impulse response of a rectangular linear array is presented. The key assumption for this algorithm is that the transducer apertures are identical and linearly distributed on an infinite rigid plane baffled with the same pitch. Two points in the observation field, which have the same position relative to two transducer apertures, share the same spatial impulse response that contributed from corresponding transducer, respectively. The observation field is discretized specifically to meet the relationship of equality. The analytical expressions of the proposed algorithm, based on the specific selection of the observation points, are derived to remove redundant calculations. In order to measure the proposed methodology, the simulation results obtained from the proposed method and the classical summation method are compared. The outcomes demonstrate that the proposed strategy can speed up the calculation procedure since it accelerates the speed-up ratio which relies upon the number of discrete points and the number of the array transducers. This development will be valuable in the development of advanced and faster linear ultrasonic phased array systems.

  16. A Fast Method to Calculate the Spatial Impulse Response for 1-D Linear Ultrasonic Phased Array Transducers

    Directory of Open Access Journals (Sweden)

    Cheng Zou

    2016-11-01

    Full Text Available A method is developed to accurately determine the spatial impulse response at the specifically discretized observation points in the radiated field of 1-D linear ultrasonic phased array transducers with great efficiency. In contrast, the previously adopted solutions only optimize the calculation procedure for a single rectangular transducer and required approximation considerations or nonlinear calculation. In this research, an algorithm that follows an alternative approach to expedite the calculation of the spatial impulse response of a rectangular linear array is presented. The key assumption for this algorithm is that the transducer apertures are identical and linearly distributed on an infinite rigid plane baffled with the same pitch. Two points in the observation field, which have the same position relative to two transducer apertures, share the same spatial impulse response that contributed from corresponding transducer, respectively. The observation field is discretized specifically to meet the relationship of equality. The analytical expressions of the proposed algorithm, based on the specific selection of the observation points, are derived to remove redundant calculations. In order to measure the proposed methodology, the simulation results obtained from the proposed method and the classical summation method are compared. The outcomes demonstrate that the proposed strategy can speed up the calculation procedure since it accelerates the speed-up ratio which relies upon the number of discrete points and the number of the array transducers. This development will be valuable in the development of advanced and faster linear ultrasonic phased array systems.

  17. Fast and accurate approximate quasiparticle band structure calculations of ZnO, CdO, and MgO polymorphs

    Science.gov (United States)

    Ataide, C. A.; Pelá, R. R.; Marques, M.; Teles, L. K.; Furthmüller, J.; Bechstedt, F.

    2017-01-01

    We investigate ZnO, CdO, and MgO oxides crystallizing in rocksalt, wurtzite, and zincblende structures. Whereas in MgO calculations, the conventional LDA-1/2 method is employed through a self-energy potential (VS), the shallow d bands in ZnO and CdO are treated through an increased amplitude (A ) of VS to modulate the self-energy of the d states to place them in the quasiparticle position. The LDA+A -1/2 scheme is applied to calculate band structures and electronic density of states of ZnO and CdO. We compare the results with those of more sophisticated quasiparticle calculations and experiments. We demonstrate that this new LDA+A -1/2 method reaches accuracy comparable to state-of-the-art methods, opening a door to study more complex systems containing shallow core electrons to the prize of LDA studies.

  18. Calculating qP-wave traveltimes in 2-D TTI media by high-order fast sweeping methods with a numerical quartic equation solver

    Science.gov (United States)

    Han, Song; Zhang, Wei; Zhang, Jie

    2017-09-01

    A fast sweeping method (FSM) determines the first arrival traveltimes of seismic waves by sweeping the velocity model in different directions meanwhile applying a local solver. It is an efficient way to numerically solve Hamilton-Jacobi equations for traveltime calculations. In this study, we develop an improved FSM to calculate the first arrival traveltimes of quasi-P (qP) waves in 2-D tilted transversely isotropic (TTI) media. A local solver utilizes the coupled slowness surface of qP and quasi-SV (qSV) waves to form a quartic equation, and solve it numerically to obtain possible traveltimes of qP-wave. The proposed quartic solver utilizes Fermat's principle to limit the range of the possible solution, then uses the bisection procedure to efficiently determine the real roots. With causality enforced during sweepings, our FSM converges fast in a few iterations, and the exact number depending on the complexity of the velocity model. To improve the accuracy, we employ high-order finite difference schemes and derive the second-order formulae. There is no weak anisotropy assumption, and no approximation is made to the complex slowness surface of qP-wave. In comparison to the traveltimes calculated by a horizontal slowness shooting method, the validity and accuracy of our FSM is demonstrated.

  19. FeynDyn: A MATLAB program for fast numerical Feynman integral calculations for open quantum system dynamics on GPUs

    Science.gov (United States)

    Dattani, Nikesh S.

    2013-12-01

    This MATLAB program calculates the dynamics of the reduced density matrix of an open quantum system modeled either by the Feynman-Vernon model or the Caldeira-Leggett model. The user gives the program a Hamiltonian matrix that describes the open quantum system as if it were in isolation, a matrix of the same size that describes how that system couples to its environment, and a spectral distribution function and temperature describing the environment’s influence on it, in addition to the open quantum system’s initial density matrix and a grid of times. With this, the program returns the reduced density matrix of the open quantum system at all moments specified by that grid of times (or just the last moment specified by the grid of times if the user makes this choice). This overall calculation can be divided into two stages: the setup of the Feynman integral, and the actual calculation of the Feynman integral for time propagation of the density matrix. When this program calculates this propagation on a multi-core CPU, it is this propagation that is usually the rate-limiting step of the calculation, but when it is calculated on a GPU, the propagation is calculated so quickly that the setup of the Feynman integral can actually become the rate-limiting step. The overhead of transferring information from the CPU to the GPU and back seems to have a negligible effect on the overall runtime of the program. When the required information cannot fit on the GPU, the user can choose to run the entire program on a CPU. Catalogue identifier: AEPX_v1_0. Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEPX_v1_0.html. Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland. Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html. No. of lines in distributed program, including test data, etc.: 703. No. of bytes in distributed program, including test data, etc.: 11026. Distribution format: tar.gz. Programming

  20. Calculation Of Change-Changing Cross Sections Of IONS Or Atoms Colliding With Fast IONS Using The Classical Trajectory Method

    Energy Technology Data Exchange (ETDEWEB)

    Kaganovich, I. D., Shnidman, Ariel, Mebane, Harrison, Davidson, R.C.

    2008-10-10

    Evaluation of ion-atom charge-changing cross sections is needed for many accelerator applications. A classical trajectory Monte Carlo (CTMC) simulation has been used to calculate ionization and charge exchange cross sections. For benchmarking purposes, an extensive study has been performed for the simple case of hydrogen and helium targets in collisions with various ions. Despite the fact that the simulation only accounts for classical mechanics, the calculations are comparable to experimental results for projectile velocities in the region corresponding to the vicinity of the maximum cross section. Shortcomings of the CTMC method for multielectron target atoms are discussed.

  1. Fast calculation of computer-generated-hologram on AMD HD5000 series GPU and OpenCL

    National Research Council Canada - National Science Library

    Shimobaba, Tomoyoshi; Ito, Tomoyoshi; Masuda, Nobuyuki; Ichihashi, Yasuyuki; Takada, Naoki

    2010-01-01

    ...) made by AMD and its new software development environment, OpenCL. Using a RV870 GPU and OpenCL, we can calculate 1,920 x 1,024 resolution of a CGH from a 3D object consisting of 1,024 points in 30 milli-seconds...

  2. Determining hydrogen-bond interactions in spider silk with 1H-13C HETCOR fast MAS solid-state NMR and DFT proton chemical shift calculations.

    Science.gov (United States)

    Holland, Gregory P; Mou, Qiushi; Yarger, Jeffery L

    2013-07-28

    Two-dimensional (2D) (1)H-(13)C heteronuclear correlation (HETCOR) solid-state NMR spectra collected with fast magic angle spinning (MAS) are used in conjunction with density functional theory (DFT) proton chemical shift calculations to determine the hydrogen-bonding strength for ordered β-sheet and disordered 310-helical structures in spider dragline silk. The hydrogen-bond strength is determined to be identical for both structures in spider silk with a 1.83-1.84 Å NH···OC hydrogen-bond distance.

  3. The Molecule Calculator: A web-server for fast quantum mechanics-based estimation of molecular properties

    CERN Document Server

    Jensen, Jan H

    2013-01-01

    A new web-server called The Molecule Calculator (MolCalc) is presented. The entry page is a molecular editor (JSmol) for interactive molecule building. The resulting structure can then be used to estimate molecular properties such as heats of formation and other thermodynamic properties, vibrational frequencies and vibrational modes, and molecular orbitals and orbital energies. These properties are computed using the GAMESS program at either the RHF/STO-3G (orbitals and orbital energies) or PM3 level of theory (all other properties) in a matter of seconds or minutes depending on the size of the molecule. The results, though approximate, can help students develop a "chemical intuition" about how molecular structure affects molecular properties, without performing the underlying calculations by hand, a near impossible task for all but the simplest chemical systems.

  4. Calculations of the thermal and fast neutron fluxes in the Syrian miniature neutron source reactor using the MCNP-4C code.

    Science.gov (United States)

    Khattab, K; Sulieman, I

    2009-04-01

    The MCNP-4C code, based on the probabilistic approach, was used to model the 3D configuration of the core of the Syrian miniature neutron source reactor (MNSR). The continuous energy neutron cross sections from the ENDF/B-VI library were used to calculate the thermal and fast neutron fluxes in the inner and outer irradiation sites of MNSR. The thermal fluxes in the MNSR inner irradiation sites were also measured experimentally by the multiple foil activation method ((197)Au (n, gamma) (198)Au and (59)Co (n, gamma) (60)Co). The foils were irradiated simultaneously in each of the five MNSR inner irradiation sites to measure the thermal neutron flux and the epithermal index in each site. The calculated and measured results agree well.

  5. Robust computational method for fast calculations of multicharged ions lineshapes affected by a low-frequency electrostatic plasma turbulence

    Science.gov (United States)

    Dalimier, E.; Oks, E.

    2017-01-01

    Transport phenomena in plasmas, such as, e.g., resistivity, can be affected by electrostatic turbulence that frequently occurs in various kinds of laboratory and astrophysical plasmas. Transport phenomena are affected most significantly by a low-frequency electrostatic turbulence—such as, e.g., ion acoustic waves, also known as ionic sound—causing anomalous resistivity. In this case, for computing profiles of spectral lines, emitted by plasma ions, by any appropriate code for diagnostic purposes, it is necessary to calculate the distribution of the total quasistatic field. For a practically important situation, where the average turbulent field is much greater than the characteristic ion microfield, we develop a robust computational method valid for any appropriate distribution of the ion microfield at a charged point. We show that the correction to the Rayleigh distribution of the turbulent field is controlled by the behavior of the ion microfield distribution at large fields—in distinction to the opposite (and therefore, erroneous) result in the literature. We also obtain a universal analytical expression for the correction to the Rayleigh distribution based on the asymptotic of the ion microfield distribution at large fields at a charged point. By comparison with various known distributions of the ion microfield, we show that our asymptotic formula has a sufficiently high accuracy. Also exact computations are used to verify the high accuracy of the method. This robust approximate, but accurate method yields faster computational results than the exact calculations and therefore should be important for practical situations requiring simultaneous computations of a large number of spectral lineshapes (e.g., for calculating opacities)—especially for laser-produced plasmas.

  6. Calculation and Analysis of B/T (Burning and/or Transmutation Rate of Minor Actinides and Plutonium Performed by Fast B/T Reactor

    Directory of Open Access Journals (Sweden)

    Marsodi

    2006-01-01

    Full Text Available Calculation and analysis of B/T (Burning and/or Transmutation rate of MA (minor actinides and Pu (Plutonium has been performed in fast B/T reactor. The study was based on the assumption that the spectrum shift of neutron flux to higher side of neutron energy had a potential significance for designing the fast B/T reactor and a remarkable effect for increasing the B/T rate of MA and/or Pu. The spectrum shifts of neutron have been performed by change MOX to metallic fuel. Blending fraction of MA and or Pu in B/T fuel and the volume ratio of fuel to coolant in the reactor core were also considered. Here, the performance of fast B/T reactor was evaluated theoretically based on the calculation results of the neutronics and burn-up analysis. In this study, the B/T rate of MA and/or Pu increased by increasing the blending fraction of MA and or Pu and by changing the F/C ratio. According to the results, the total B/T rate, i.e. [B/T rate]MA + [B/T rate]Pu, could be kept nearly constant under the critical condition, if the sum of the MA and Pu inventory in the core is nearly constant. The effect of loading structure was examined for inner or outer loading of concentric geometry and for homogeneous loading. Homogeneous loading of B/T fuel was the good structure for obtaining the higher B/T rate, rather than inner or outer loading

  7. A Fast Parallel Algorithm for Selected Inversion of Structured Sparse Matrices with Application to 2D Electronic Structure Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Lin; Yang, Chao; Lu, Jiangfeng; Ying, Lexing; E, Weinan

    2009-09-25

    We present an efficient parallel algorithm and its implementation for computing the diagonal of $H^-1$ where $H$ is a 2D Kohn-Sham Hamiltonian discretized on a rectangular domain using a standard second order finite difference scheme. This type of calculation can be used to obtain an accurate approximation to the diagonal of a Fermi-Dirac function of $H$ through a recently developed pole-expansion technique \\cite{LinLuYingE2009}. The diagonal elements are needed in electronic structure calculations for quantum mechanical systems \\citeHohenbergKohn1964, KohnSham 1965,DreizlerGross1990. We show how elimination tree is used to organize the parallel computation and how synchronization overhead is reduced by passing data level by level along this tree using the technique of local buffers and relative indices. We analyze the performance of our implementation by examining its load balance and communication overhead. We show that our implementation exhibits an excellent weak scaling on a large-scale high performance distributed parallel machine. When compared with standard approach for evaluating the diagonal a Fermi-Dirac function of a Kohn-Sham Hamiltonian associated a 2D electron quantum dot, the new pole-expansion technique that uses our algorithm to compute the diagonal of $(H-z_i I)^-1$ for a small number of poles $z_i$ is much faster, especially when the quantum dot contains many electrons.

  8. Measurement and calculation of fast neutron and gamma spectra in well defined cores in LR-0 reactor.

    Science.gov (United States)

    Košťál, Michal; Matěj, Zdeněk; Cvachovec, František; Rypar, Vojtěch; Losa, Evžen; Rejchrt, Jiří; Mravec, Filip; Veškrna, Martin

    2017-02-01

    A well-defined neutron spectrum is essential for many types of experimental topics and is also important for both calibration and testing of spectrometric and dosimetric detectors. Provided it is well described, such a spectrum can also be employed as a reference neutron field that is suitable for validating selected cross sections. The present paper aims to compare calculations and measurements of such a well-defined spectra in geometrically similar cores of the LR-0 reactor with fuel containing slightly different enrichments (2%, 3.3% and 3.6%). The common feature to all cores is a centrally located dry channel which can be used for the insertion of studied materials. The calculation of neutron and gamma spectra was realized with the MCNP6 code using ENDF/B-VII.0, JEFF-3.1, JENDL-3.3, ROSFOND-2010 and CENDL-3.1 nuclear data libraries. Only minor differences in neutron and gamma spectra were found in the comparison of the presented reactor cores with different fuel enrichments. One exception is the gamma spectrum in the higher energy region (above 8MeV), where more pronounced variations could be observed.

  9. Analysis of Heart Rate Variability During Breath-Holding Using Fast and Continuous Calculation Method of Frequency and Power

    Science.gov (United States)

    Yoshida, Yutaka; Yokoyama, Kiyoko; Ishii, Naohiro

    Many reports show that dominant frequency of high frequency component(HF:0.15∼0.4Hz) of heart rate time series is synchronized with the respiratory frequency. In this paper, we proposed the method for estimating the condition of respiration continuously using dominant frequency and power of HF (HFP) of heart rate time series. Dominant frequency and HFP is calculated from the interval of the neighboring two extreme points and the subtraction of the neighboring two extremals.In the experimental results, high frequency components did not disappear completely during breath-holding. This fact is different from the previous study. Subjects were classified into two groups. In one group, dominant frequency of the HF is significant increased during breath-holding compared with normal breathing. In the other group, this phenomenon was not observed. On the other hand, HFP of total subjects significantly decreased during breath-holding compared with normal breathing. Correct rate during breath-holding and error rate during rest and recovery are calculated using HFP. In the results, average and S. D. of correct rate during breath-holding were 65.0±26.3%. Correct rate of 18 subjects was 80.0±14.1% and correct rate of other 8 subjects was 31.5±11.9%. Our method is expected to apply to the development of the respiratory monitor which can measure respiratory condition with non-restricted in continuously.

  10. Optimal representation of the bath response function & fast calculation of influence functional coefficients in open quantum systems with BATHFIT 1

    CERN Document Server

    Dattani, Nikesh S; Pollock, Felix A

    2012-01-01

    Today's most popular techniques for accurately calculating the dynamics of the reduced density operator in an open quantum system, either require, or gain great computational benefits, from representing the bath response function a(t) in the form a(t)={\\Sigma}_k^K p_k e^{O_k t} . For some of these techniques, the number of terms in the series K plays the lead role in the computational cost of the calculation, and is therefore often a limiting factor in simulating open quantum system dynamics. We present an open source MATLAB program called BATHFIT 1, whose input is any spectral distribution functions J(w) or bath response function, and whose output attempts to be the set of parameters {p_k,w_k}_k=1^K such that for a given value of K, the series {\\Sigma}_k^k p_k e^{O_k t} is as close as possible to a(t). This should allow the user to represent a(t) as accurately as possible with as few parameters as possible. The program executes non-linear least squares fitting, and for a very wide variety of spectral distrib...

  11. Unsaturated-zone fast-path flow calculations for Yucca Mountain groundwater travel time analyses (GWTT-94)

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, B.W.; Altman, S.J. [Sandia National Labs., Albuquerque, NM (United States); Robey, T.H. [Spectra Research Institute, Albuquerque, NM (United States)] [and others

    1995-08-01

    Evaluation of groundwater travel time (GWTT) is required as part of the investigation of the suitability of Yucca Mountain as a potential high-level nuclear-waste repository site. The Nuclear Regulatory Commission`s GWTT regulation is considered to be a measure of the intrinsic ability of the site to contain radionuclide releases from the repository. The work reported here is the first step in a program to provide an estimate of GWTT at the Yucca Mountain site in support of the DOE`s Technical Site Suitability and as a component of a license application. Preliminary estimation of the GWTT distribution in the unsaturated zone was accomplished using a numerical model of the physical processes of groundwater flow in the fractured, porous medium of the bedrock. Based on prior investigations of groundwater flow at the site, fractures are thought to provide the fastest paths for groundwater flow; conditions that lead to flow in fractures were investigated and simulated. Uncertainty in the geologic interpretation of Yucca Mountain was incorporated through the use of geostatistical simulations, while variability of hydrogeologic parameters within each unit was accounted for by the random sampling of parameter probability density functions. The composite-porosity formulation of groundwater flow was employed to simulate flow in both the matrix and fracture domains. In this conceptualization, the occurrence of locally saturated conditions within the unsaturated zone is responsible for the initiation of fast-path flow through fractures. The results of the GWTT-94 study show that heterogeneity in the hydraulic properties of the model domain is an important factor in simulating local regions of high groundwater saturation. Capillary-pressure conditions at the surface boundary influence the extent of the local saturation simulated.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Dzhalandinov A.

    2016-01-01

    Full Text Available 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.

  14. Fast finite element calculation of effective conductivity of random continuum microstructures: The recursive Poincaré-Steklov operator method

    Science.gov (United States)

    Hardin, Thomas J.; Schuh, Christopher A.

    2017-08-01

    The effective conductivity of a block of composite can be extracted from the Dirichlet-to-Neumann Poincaré-Steklov operator (PSO) for that block. In this paper, a domain decomposition method for computing the PSO over a finite element mesh is discussed. A new numerical strategy is introduced to accelerate the computation of this operator, using the Schur complement to calculate the PSO for the smallest subdomains, then recursively merging subdomain PSOs up to the full domain. At each step of the algorithm, information extraneous to the PSO is discarded. The effective conductivity values computed by this method are identical to those obtained from a basic Finite Element Method, an order of magnitude faster and with much less computer memory consumed. As proof of concept, effective conductivity measurements are presented for a percolating random fractal-like microstructure across a range of phase fractions.

  15. Doubly-differential cross section calculations for $K$-shell vacancy production in lithium by fast O$^{8+}$ ion impact

    CERN Document Server

    Śpiewanowski, M D; Horbatsch, M; Kirchner, T

    2016-01-01

    Inner-shell vacancy production for the O$^{8+}$-Li collision system at 1.5 MeV/amu is studied theoretically. The theory combines single-electron amplitudes for each electron in the system to extract multielectron information about the collision process. Doubly-differential cross sections obtained in this way are then compared with the recent experimental data by LaForge et al. [J. Phys. B 46, 031001 (2013)] yielding good resemblance, especially for low outgoing electron energy. A careful analysis of the processes that contribute to inner-shell vacancy production shows that the improvement of the results as compared to single-active-electron calculations can be attributed to the leading role of two-electron excitation-ionization processes.

  16. Efficient dielectric matrix calculations using the Lanczos algorithm for fast many-body G0W0 implementations

    Science.gov (United States)

    Laflamme Janssen, Jonathan; Rousseau, Bruno; Côté, Michel

    2015-03-01

    We present a G0W0 implementation that assesses the two major bottlenecks of traditional plane-waves implementations, the summations over conduction states and the inversion of the dielectric matrix, without introducing new approximations in the formalism. The first bottleneck is circumvented by converting the summations into Sternheimer equations. Then, the novel avenue of expressing the dielectric matrix in a Lanczos basis is developed, which reduces the matrix size by orders of magnitude while being computationally efficient. We also develop a model dielectric operator that allows us to further reduce the size of the dielectric matrix without accuracy loss. Furthermore, we develop a scheme that reduces the numerical cost of the contour deformation technique to the level of the lightest plasmon pole model. Finally, the use of the simplified quasiminimal residual scheme in replacement of the conjugate gradients algorithm allows a direct evaluation of the G0W0 corrections at the desired real frequencies, without need for analytical continuation. The performance of the resulting G0W0 implementation is demonstrated by comparison with a traditional plane-waves implementation, which reveals a 500-fold speedup for the silane molecule. Finally, the accuracy of our G0W0 implementation is demonstrated by comparison with other G0W0 calculations and experimental results.

  17. Improved algorithms for the calculation of resolved resonance cross sections with applications to the structural Doppler effect in fast reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, R N; Toppel, B J; Henryson, H II

    1980-10-01

    Motivated by a need for an economical yet rigorous tool which can address the computation of the structural material Doppler effect, an extremely efficient improved RABANL capability has been developed utilizing the fact that the Doppler broadened line shape functions become essentially identical to the natural line shape functions or Lorentzian limits beyond about 100 Doppler widths from the resonance energy, or when the natural width exceeds about 200 Doppler widths. The computational efficiency has been further enhanced by preprocessing or screening a significant number of selected resonances during library preparation into composition and temperature independent smooth background cross sections. The resonances which are suitable for such pre-processing are those which are either very broad or those which are very weak. The former contribute very little to the Doppler effect and their self-shielding effect can readily be averaged into slowly varying background cross section data, while the latter contribute very little to either the Doppler or to self-shielding effects. To illustrate the accuracy and efficiency of the improved RABANL algorithms and resonance screening techniques, calculations have been performed for two systems, the first with a composition typical of the STF converter region and the second typical of an LMFBR core composition. Excellent agreement has been found for RABANL compared to the reference Monte Carlo solution obtained using the code VIM, and improved results have also been obtained for the narrow resonance approximation in the ultra-fine-group option of MC/sup 2/-2.

  18. A simple and fast physics-based analytical method to calculate therapeutic and stray doses from external beam, megavoltage x-ray therapy.

    Science.gov (United States)

    Jagetic, Lydia J; Newhauser, Wayne D

    2015-06-21

    State-of-the-art radiotherapy treatment planning systems provide reliable estimates of the therapeutic radiation but are known to underestimate or neglect the stray radiation exposures. Most commonly, stray radiation exposures are reconstructed using empirical formulas or lookup tables. The purpose of this study was to develop the basic physics of a model capable of calculating the total absorbed dose both inside and outside of the therapeutic radiation beam for external beam photon therapy. The model was developed using measurements of total absorbed dose in a water-box phantom from a 6 MV medical linear accelerator to calculate dose profiles in both the in-plane and cross-plane direction for a variety of square field sizes and depths in water. The water-box phantom facilitated development of the basic physical aspects of the model. RMS discrepancies between measured and calculated total absorbed dose values in water were less than 9.3% for all fields studied. Computation times for 10 million dose points within a homogeneous phantom were approximately 4 min. These results suggest that the basic physics of the model are sufficiently simple, fast, and accurate to serve as a foundation for a variety of clinical and research applications, some of which may require that the model be extended or simplified based on the needs of the user. A potentially important advantage of a physics-based approach is that the model is more readily adaptable to a wide variety of treatment units and treatment techniques than with empirical models.

  19. The features of neutronic calculations for fast reactors with hybrid cores on the basis of BFS-62-3A critical assembly experiments

    Energy Technology Data Exchange (ETDEWEB)

    Mitenkova, E. F.; Novikov, N. V. [Nuclear Safety Inst. of Russian Academy of Sciences, B. Tulskaya 52, Moscow, 115119 (Russian Federation); Blokhin, A. I. [State Scientific Center of Russian Federation, Inst. of Physics and Power Engineering Named after A.I. Leypunsky, Bondarenko Square 1, Obninsk, Kaluga Region, 249030 (Russian Federation)

    2012-07-01

    The different (U-Pu) fuel compositions are considered for next generation of sodium fast breeder reactors. The considerable discrepancies in axial and radial neutron spectra for hybrid reactor systems compared to the cores with UO{sub 2} fuel cause increasing uncertainty of generating the group nuclear constants in those reactor systems. The calculation results of BFS-62-3A critical assembly which is considered as full-scale model of BN-600 hybrid core with steel reflector specify quite different spectra in local areas. For those systems the MCNP 5 calculations demonstrate significant sensitivity of effective multiplication factor K{sub eff} and spectral indices to nuclear data libraries. For {sup 235}U, {sup 238}U, {sup 239}Pu the results of calculated radial fission rate distributions against the reconstructed ones are analyzed. Comparative analysis of spectral indices, neutron spectra and radial fission rate distributions are performed using the different versions of ENDF/B, JENDL-3.3, JENDL-4, JEFF-3.1.1 libraries and BROND-3 for Fe, Cr isotopes. For analyzing the fission rate sensitivity to the plutonium presence in the fuel {sup 239}Pu is substituted for {sup 235}U (enrichment 90%) in the FA areas containing the plutonium. For {sup 235}U, {sup 238}U, {sup 239}Pu radial fission rate distributions the explanation of pick values discrepancies is based on the group fission constants analyses and possible underestimation of some features at the experimental data recovery method (Westcott factors, temperature dependence). (authors)

  20. Probing intermolecular interactions in a diethylcarbamazine citrate salt by fast MAS (1)H solid-state NMR spectroscopy and GIPAW calculations.

    Science.gov (United States)

    Venâncio, Tiago; Oliveira, Lyege Magalhaes; Ellena, Javier; Boechat, Nubia; Brown, Steven P

    2017-03-02

    Fast magic-angle spinning (MAS) NMR is used to probe intermolecular interactions in a diethylcarbamazine salt, that is widely used as a treatment against adult worms of Wuchereria bancrofti which cause a common disease in tropical countries named filariasis. Specifically, a dihydrogen citrate salt that has improved thermal stability and solubility as compared to the free form is studied. One-dimensional (1)H, (13)C and (15)N and two-dimensional (1)H-(13)C and (14)N-(1)H heteronuclear correlation NMR experiments under moderate and fast MAS together with GIPAW (CASTEP) calculations enable the assignment of the (1)H, (13)C and (14)N/(15)N resonances. A two-dimensional (1)H-(1)H double-quantum (DQ) -single-quantum (SQ) MAS spectrum recorded with BaBa recoupling at 60kHz MAS identifies specific proton-proton proximities associated with citrate-citrate and citrate-diethylcarbamazine intermolecular interactions. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. A Fast Numerical Method for the Calculation of the Equilibrium Isotopic Composition of a Transmutation System in an Advanced Fuel Cycle

    Directory of Open Access Journals (Sweden)

    F. Álvarez-Velarde

    2012-01-01

    Full Text Available A fast numerical method for the calculation in a zero-dimensional approach of the equilibrium isotopic composition of an iteratively used transmutation system in an advanced fuel cycle, based on the Banach fixed point theorem, is described in this paper. The method divides the fuel cycle in successive stages: fuel fabrication, storage, irradiation inside the transmutation system, cooling, reprocessing, and incorporation of the external material into the new fresh fuel. The change of the fuel isotopic composition, represented by an isotope vector, is described in a matrix formulation. The resulting matrix equations are solved using direct methods with arbitrary precision arithmetic. The method has been successfully applied to a double-strata fuel cycle with light water reactors and accelerator-driven subcritical systems. After comparison to the results of the EVOLCODE 2.0 burn-up code, the observed differences are about a few percents in the mass estimations of the main actinides.

  2. Measurement and calculation of the fast-neutron and photon spectra from the core boundary to the biological shielding in the WWER-1000 reactor model.

    Science.gov (United States)

    Osmera, B; Cvachovec, F; Kyncl, J; Smutný, V

    2005-01-01

    The fast-neutron and photon space-energy distributions have been measured in an axially (1.25 m active height) and azimuthally (60 degree symmetry sector) shortened model of the WWER-1000 reactor assembled in the LR-0 experimental reactor. The space-energy distributions have been calculated with the stochastic code MCNP and the deterministic three-dimensional code TORT. Selected results are presented and discussed in the paper. This work has been done in the frame of the EU 5th FW project REDOS REDOS, Reactor Dosimetry: Accurate determination and benchmarking of radiation field parameters, relevant for reactor pressure vessel monitoring. EURATOM Programme, Call 2000/C 294/04). All geometry and material composition data of the model as well as the available experimental data were carefully checked and revised.

  3. Recoil proton, alpha particle, and heavy ion impacts on microdosimetry and RBE of fast neutrons: analysis of kerma spectra calculated by Monte Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Pignol, J.-P. [Toronto-Sunnybrook Regional Cancer Centre, Radiotherapy Dept., Toronto, Ontario (Canada); Slabbert, J. [National Accelerator Centre, Faure (South Africa)

    2001-02-01

    Fast neutrons (FN) have a higher radio-biological effectiveness (RBE) compared with photons, however the mechanism of this increase remains a controversial issue. RBE variations are seen among various FN facilities and at the same facility when different tissue depths or thicknesses of hardening filters are used. These variations lead to uncertainties in dose reporting as well as in the comparisons of clinical results. Besides radiobiology and microdosimetry, another powerful method for the characterization of FN beams is the calculation of total proton and heavy ion kerma spectra. FLUKA and MCNP Monte Carlo code were used to simulate these kerma spectra following a set of microdosimetry measurements performed at the National Accelerator Centre. The calculated spectra confirmed major classical statements: RBE increase is linked to both slow energy protons and alpha particles yielded by (n,{alpha}) reactions on carbon and oxygen nuclei. The slow energy protons are produced by neutrons having an energy between 10 keV and 10 MeV, while the alpha particles are produced by neutrons having an energy between 10 keV and 15 MeV. Looking at the heavy ion kerma from <15 MeV and the proton kerma from neutrons <10 MeV, it is possible to anticipate y* and RBE trends. (author)

  4. Recoil proton, alpha particle, and heavy ion impacts on microdosimetry and RBE of fast neutrons: analysis of kerma spectra calculated by Monte Carlo simulation.

    Science.gov (United States)

    Pignol, J P; Slabbert, J

    2001-02-01

    Fast neutrons (FN) have a higher radio-biological effectiveness (RBE) compared with photons, however the mechanism of this increase remains a controversial issue. RBE variations are seen among various FN facilities and at the same facility when different tissue depths or thicknesses of hardening filters are used. These variations lead to uncertainties in dose reporting as well as in the comparisons of clinical results. Besides radiobiology and microdosimetry, another powerful method for the characterization of FN beams is the calculation of total proton and heavy ion kerma spectra. FLUKA and MCNP Monte Carlo code were used to simulate these kerma spectra following a set of microdosimetry measurements performed at the National Accelerator Centre. The calculated spectra confirmed major classical statements: RBE increase is linked to both slow energy protons and alpha particles yielded by (n,alpha) reactions on carbon and oxygen nuclei. The slow energy protons are produced by neutrons having an energy between 10 keV and 10 MeV, while the alpha particles are produced by neutrons having an energy between 10 keV and 15 MeV. Looking at the heavy ion kerma from neutrons <10 MeV, it is possible to anticipate y* and RBE trends.

  5. Improved performances of the fast reactor calculational system ERANOS-ERALIB1 due to improved a priori nuclear data and consideration of additional specific integral data

    Energy Technology Data Exchange (ETDEWEB)

    Fort, E. E-mail: eric.fort@cea.fr; Rimpault, G.; Bosq, J-C.; Camous, B.; Zammit, V.; Dupont, E.; Jacqmin, R.; Smith, P.; Biron, D. E-mail: didier.biron@edf.fr; Verrier, D. E-mail: dverrier@framatome.fr

    2003-12-01

    A single consistent scheme of calculational methods and nuclear data called ERANOS-ERALIB1 was produced in 1996 to calculate fast reactor neutronic parameters. It represents a significant improvement on previous schemes such as CARNAVAL-IV, PROPANE and VASCO, each of which were required in order to calculate one specific application. The nuclear data library ERALIB1 has been obtained by a consistent statistical adjustment based on 355 integral data from 71 different systems. The performance of ERALIB1 is excellent, as demonstrated during its validation for which all the k{sub eff} SUPER-PHENIX data were reproduced to within 70 pcm. The only restriction on this satisfactory performance is related to the rather poor prediction of the sodium void reactivity effect. This was due to very bad nuclear data for {sup 23}Na, and the unsatisfactory methods used to calculate the sensitivity coefficients for the sodium void reactivity variation {delta}{rho}{sub Na}. To improve the performance relative to this point and to enlarge the domain of validation several actions have been undertaken: - a revision of the formalism and algorithms used to calculate the derivatives of {delta}{rho}{sub Na} to the sodium cross section data,; - a significant enlargement of the integral data base related to this aspect of the sodium void effect. Compared to the initial data base established in support of ERALIB1, several additional (18) sodium void configurations corresponding to voids of different volumes at different core locations have been studied. In order to broaden the range of application of the improved library, which will be called ERALIB1.A, significant effort has been devoted to additional configurations which have firstly been evaluated, and then if judged suitable, included in the adjustment process. They are related to two specifically targeted experimental programmes: - a study of neutron deep penetration. Several configurations of the JANUS experimental programme (shielding

  6. Comparison between analyzed and calculated nutrient content of fast foods using two consecutive versions of the Danish food composition databank: FOODCOMP and FRIDA

    DEFF Research Database (Denmark)

    Biltoft-Jensen, Anja Pia; Knuthsen, Pia; Saxholt, Erling

    2017-01-01

    -to-eat fast foods were collected from fast food outlets, separated into their components and weighed. Typical components were bread, French fries, vegetables, meat and dressings. The fast foods were analyzed, and energy, protein, saturated fat, iron, thiamin, potassium and sodium contents were compared...

  7. 选择性计算的快速非局部均值图像去噪%Fast Nonlocal Means Image Denoising Algorithm Using Selective Calculation

    Institute of Scientific and Technical Information of China (English)

    罗学刚; 吕俊瑞; 王华军; 杨强

    2015-01-01

    A fast nonlocal means (NLM) image denoising method with selective calculation is proposed to solve the problem that the computational cost of similarity weights is high. By using L2 Norm successive elimination, a large number of pixels of low similarity van be rejected through a small amount of additive operations on integral image, and the massive calculation on measuring similarity can be effectively reduced. According to spatial coherence in the image domain, an approach for adaptive search area based on patch geodesic distance is proposed. Experimental results demonstrate that the proposed method, compared with the state-of-the-art algorithms, can not only accelerate the nonlocal means algorithm, but also elevate the image quality.%针对非局部均值(NLM)图像去噪算法度量像素间的相似性计算强度高的问题,提出了一种选择性计算的快速NLM去噪方法。在图像块像素灰度值向量空间距离计算时,利用L2范数逐次消元法,只需在图像积分图上通过少量加法运算即可剔除大量相似性低的像素点,有效地减少计算强度。根据图像空间相关性强的特点,提出了基于patch测地线距离的动态调整搜索区域的方法。实验结果表明,与其他经典算法相比,该方法获得了较好的加速,也提升了NLM算法的去噪性能。

  8. A fast parallel code for calculating energies and oscillator strengths of many-electron atoms at neutron star magnetic field strengths in adiabatic approximation

    Science.gov (United States)

    Engel, D.; Klews, M.; Wunner, G.

    2009-02-01

    We have developed a new method for the fast computation of wavelengths and oscillator strengths for medium-Z atoms and ions, up to iron, at neutron star magnetic field strengths. The method is a parallelized Hartree-Fock approach in adiabatic approximation based on finite-element and B-spline techniques. It turns out that typically 15-20 finite elements are sufficient to calculate energies to within a relative accuracy of 10-5 in 4 or 5 iteration steps using B-splines of 6th order, with parallelization speed-ups of 20 on a 26-processor machine. Results have been obtained for the energies of the ground states and excited levels and for the transition strengths of astrophysically relevant atoms and ions in the range Z=2…26 in different ionization stages. Catalogue identifier: AECC_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AECC_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 3845 No. of bytes in distributed program, including test data, etc.: 27 989 Distribution format: tar.gz Programming language: MPI/Fortran 95 and Python Computer: Cluster of 1-26 HP Compaq dc5750 Operating system: Fedora 7 Has the code been vectorised or parallelized?: Yes RAM: 1 GByte Classification: 2.1 External routines: MPI/GFortran, LAPACK, PyLab/Matplotlib Nature of problem: Calculations of synthetic spectra [1] of strongly magnetized neutron stars are bedevilled by the lack of data for atoms in intense magnetic fields. While the behaviour of hydrogen and helium has been investigated in detail (see, e.g., [2]), complete and reliable data for heavier elements, in particular iron, are still missing. Since neutron stars are formed by the collapse of the iron cores of massive stars, it may be assumed that their atmospheres contain an iron plasma. Our objective is to fill the gap

  9. FAST: FAST Analysis of Sequences Toolbox.

    Science.gov (United States)

    Lawrence, Travis J; Kauffman, Kyle T; Amrine, Katherine C H; Carper, Dana L; Lee, Raymond S; Becich, Peter J; Canales, Claudia J; Ardell, David H

    2015-01-01

    FAST (FAST Analysis of Sequences Toolbox) provides simple, powerful open source command-line tools to filter, transform, annotate and analyze biological sequence data. Modeled after the GNU (GNU's Not Unix) Textutils such as grep, cut, and tr, FAST tools such as fasgrep, fascut, and fastr make it easy to rapidly prototype expressive bioinformatic workflows in a compact and generic command vocabulary. Compact combinatorial encoding of data workflows with FAST commands can simplify the documentation and reproducibility of bioinformatic protocols, supporting better transparency in biological data science. Interface self-consistency and conformity with conventions of GNU, Matlab, Perl, BioPerl, R, and GenBank help make FAST easy and rewarding to learn. FAST automates numerical, taxonomic, and text-based sorting, selection and transformation of sequence records and alignment sites based on content, index ranges, descriptive tags, annotated features, and in-line calculated analytics, including composition and codon usage. Automated content- and feature-based extraction of sites and support for molecular population genetic statistics make FAST useful for molecular evolutionary analysis. FAST is portable, easy to install and secure thanks to the relative maturity of its Perl and BioPerl foundations, with stable releases posted to CPAN. Development as well as a publicly accessible Cookbook and Wiki are available on the FAST GitHub repository at https://github.com/tlawrence3/FAST. The default data exchange format in FAST is Multi-FastA (specifically, a restriction of BioPerl FastA format). Sanger and Illumina 1.8+ FastQ formatted files are also supported. FAST makes it easier for non-programmer biologists to interactively investigate and control biological data at the speed of thought.

  10. FAST: FAST Analysis of Sequences Toolbox

    Directory of Open Access Journals (Sweden)

    Travis J. Lawrence

    2015-05-01

    Full Text Available FAST (FAST Analysis of Sequences Toolbox provides simple, powerful open source command-line tools to filter, transform, annotate and analyze biological sequence data. Modeled after the GNU (GNU’s Not Unix Textutils such as grep, cut, and tr, FAST tools such as fasgrep, fascut, and fastr make it easy to rapidly prototype expressive bioinformatic workflows in a compact and generic command vocabulary. Compact combinatorial encoding of data workflows with FAST commands can simplify the documentation and reproducibility of bioinformatic protocols, supporting better transparency in biological data science. Interface self-consistency and conformity with conventions of GNU, Matlab, Perl, BioPerl, R and GenBank help make FAST easy and rewarding to learn. FAST automates numerical, taxonomic, and text-based sorting, selection and transformation of sequence records and alignment sites based on content, index ranges, descriptive tags, annotated features, and in-line calculated analytics, including composition and codon usage. Automated content- and feature-based extraction of sites and support for molecular population genetic statistics makes FAST useful for molecular evolutionary analysis. FAST is portable, easy to install and secure thanks to the relative maturity of its Perl and BioPerl foundations, with stable releases posted to CPAN. Development as well as a publicly accessible Cookbook and Wiki are available on the FAST GitHub repository at https://github.com/tlawrence3/FAST. The default data exchange format in FAST is Multi-FastA (specifically, a restriction of BioPerl FastA format. Sanger and Illumina 1.8+ FastQ formatted files are also supported. FAST makes it easier for non-programmer biologists to interactively investigate and control biological data at the speed of thought.

  11. Whole-Core Monte Carlo Calculation Based on Fission and Surface Source Iteration Method Applied to a Fast Reactor Core Configuration

    Energy Technology Data Exchange (ETDEWEB)

    Jo, YuGwon; Cho, Nam Zin [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2015-05-15

    In this paper, the FSS iteration method is applied to the fast reactor where the neutron mean-free-path is around 10 times longer than that in the thermal reactor. The FSS iteration method with domain-based parallelism is tested on a two-dimensional continuous-energy fast reactor test problem. The multiplication factor and the pinwise fission-rate distributions of the FSS iteration method show good agreements with those of the conventional power method. A local domain is chosen as a cluster of 19 assemblies, taking into account the longer neutron mean-free-path. In the future, another type of local domain can be defined to take into account reflector assemblies and shield assemblies with appropriate boundary conditions. In the test problem, the multiplication factor and the pinwise fission-rate distributions of the FSS iteration method show good agreements with those of the conventional power method. Although the domain decomposition is easily achieved by the FSS iteration method, load-imbalance of local problems causes idle times in the processors. Applying the source splitting scheme and assigning different numbers of processors to local problems will reduce this problem.

  12. FAST User Guide

    Science.gov (United States)

    Walatka, Pamela P.; Clucas, Jean; McCabe, R. Kevin; Plessel, Todd; Potter, R.; Cooper, D. M. (Technical Monitor)

    1994-01-01

    The Flow Analysis Software Toolkit, FAST, is a software environment for visualizing data. FAST is a collection of separate programs (modules) that run simultaneously and allow the user to examine the results of numerical and experimental simulations. The user can load data files, perform calculations on the data, visualize the results of these calculations, construct scenes of 3D graphical objects, and plot, animate and record the scenes. Computational Fluid Dynamics (CFD) visualization is the primary intended use of FAST, but FAST can also assist in the analysis of other types of data. FAST combines the capabilities of such programs as PLOT3D, RIP, SURF, and GAS into one environment with modules that share data. Sharing data between modules eliminates the drudgery of transferring data between programs. All the modules in the FAST environment have a consistent, highly interactive graphical user interface. Most commands are entered by pointing and'clicking. The modular construction of FAST makes it flexible and extensible. The environment can be custom configured and new modules can be developed and added as needed. The following modules have been developed for FAST: VIEWER, FILE IO, CALCULATOR, SURFER, TOPOLOGY, PLOTTER, TITLER, TRACER, ARCGRAPH, GQ, SURFERU, SHOTET, and ISOLEVU. A utility is also included to make the inclusion of user defined modules in the FAST environment easy. The VIEWER module is the central control for the FAST environment. From VIEWER, the user can-change object attributes, interactively position objects in three-dimensional space, define and save scenes, create animations, spawn new FAST modules, add additional view windows, and save and execute command scripts. The FAST User Guide uses text and FAST MAPS (graphical representations of the entire user interface) to guide the user through the use of FAST. Chapters include: Maps, Overview, Tips, Getting Started Tutorial, a separate chapter for each module, file formats, and system

  13. Tight-Binding Approximations to Time-Dependent Density Functional Theory - a fast approach for the calculation of electronically excited states

    CERN Document Server

    Rüger, Robert; Heine, Thomas; Visscher, Lucas

    2016-01-01

    We propose a new method of calculating electronically excited states that combines a density functional theory (DFT) based ground state calculation with a linear response treatment that employs approximations used in the time-dependent density functional based tight binding (TD-DFTB) approach. The new method termed TD-DFT+TB does not rely on the DFTB parametrization and is therefore applicable to systems involving all combinations of elements. We show that the new method yields UV/Vis absorption spectra that are in excellent agreement with computationally much more expensive time-dependent density functional theory (TD-DFT) calculations. Errors in vertical excitation energies are reduced by a factor of two compared to TD-DFTB.

  14. Fast Calculation Model and Theoretical Analysis of Rotor Unbalanced Magnetic Pull for Inter-Turn Short Circuit of Field Windings of Non-Salient Pole Generators

    Directory of Open Access Journals (Sweden)

    Guangtao Zhang

    2017-05-01

    Full Text Available Inter-turn short circuit of field windings (ISCFW may cause the field current of a generator to increase, output reactive power to decrease, and unit vibration to intensify, seriously affecting its safe and stable operation. Full integration of mechanical and electrical characteristics can improve the sensitivity of online monitoring, and detect the early embryonic period fault of small turns. This paper studies the calculations and variations of unbalanced magnetic pull (UMP, of which the excitation source of rotor vibration is the basis and key to online fault monitoring. In grid load operation, ISCFW are first calculated with the multi-loop method, so as to obtain the numerical solutions of the stator and the rotor currents during the fault. Next, the air-gap magnetic field of the ISCFW is analyzed according to the actual composition modes of the motor loops in the fault, so as to obtain the analytic expressions of the air-gap magnetic motive force (MMF and magnetic density. The UMP of the rotor is obtained by solving the integral of the Maxwell stress. The correctness of the electric quantity calculation is verified by the ISCFW experiment, conducted in a one pair-pole non-salient pole model machine. On this basis, comparing the simulation analysis with the calculation results of the model in this paper not only verifies the accuracy of the electromagnetic force calculation, but also proves that the latter has the advantages of a short time consumption and high efficiency. Finally, the influencing factors and variation law of UMP are analyzed by means of an analytic model. This develops a base for the online monitoring of ISCFW with the integration of mechanical and electrical information.

  15. Using simple molecular orbital calculations to predict disease: fast DFT methods applied to enzymes implicated in PKU, Parkinson's disease and Obsessive Compulsive Disorder

    Science.gov (United States)

    Hofto, Laura; Hofto, Meghan; Cross, Jessica; Cafiero, Mauricio

    2007-09-01

    Many diseases can be traced to point mutations in the DNA coding for specific enzymes. These point mutations result in the change of one amino acid residue in the enzyme. We have developed a model using simple molecular orbital calculations which can be used to quantitatively determine the change in interaction between the enzyme's active site and necessary ligands upon mutation. We have applied this model to three hydroxylase proteins: phenylalanine hydroxylase, tyrosine hydroxylase, and tryptophan hydroxylase, and we have obtained excellent correlation between our results and observed disease symptoms. Furthermore, we are able to use this agreement as a baseline to screen other mutations which may also cause onset of disease symptoms. Our focus is on systems where the binding is due largely to dispersion, which is much more difficult to model inexpensively than pure electrostatic interactions. Our calculations are run in parallel on a sixteen processor cluster of 64-bit Athlon processors.

  16. 脉冲磁场激励下圆柱导体内瞬态涡流场的快速计算%Fast Calculation of Transient Eddy Current Field in Cylindrical Conductor Excited by Pulsed Magnetic Field

    Institute of Scientific and Technical Information of China (English)

    辛伟

    2013-01-01

    The theoretical model of transient eddy current field is built in cylindrical conductor excited by pulsed magnetic field. Theoretical calculation and experimental measurement of cylindrical conductor in pulsed magnetic field are carried out. The theoretical results are compared with the experimental results in a good agreement, indicate that the fast calculation method of transient eddy current field in cylindrical conductor is effective.%建立了脉冲磁场激励下圆柱导体内瞬态涡流场的理论模型.实现了瞬态涡流场的快速计算.通过实例表明上述圆柱导体内瞬态涡流场的快速计算方法有效.

  17. Procedure of calculation of the spatial distribution of temperatures and heat fluxes in the steam generator of a nuclear power installation with an RBEC fast-neutron reactor

    Science.gov (United States)

    Frolov, A. A.; Sedov, A. A.

    2016-08-01

    A method for combined 3D/1D-modeling of thermohydraulics of a once-through steam generator (SG) based on the joint analysis of three-dimensional thermo- and hydrodynamics of a single-phase heating coolant in the intertube space and one-dimensional thermohydraulics of steam-generating channels (tubes) with the use of well-known friction and heat-transfer correlations under various boiling conditions is discussed. This method allows one to determine the spatial distribution of temperatures and heat fluxes of heat-exchange surfaces of SGs with a single-phase heating coolant in the intertube space and with steam generation within tubes. The method was applied in the analytical investigation of typical operation of a once-through SG of a nuclear power installation with an RBEC fast-neutron heavy-metal reactor that is being designed by Kurchatov Institute in collaboration with OKB GIDROPRESS and Leipunsky Institute of Physics and Power Engineering. Flow pattern and temperature fields were obtained for the heavy-metal heating coolant in the intertube space. Nonuniformities of heating of the steam-water coolant in different heat-exchange tubes and nonuniformities in the distribution of heat fluxes at SG heat-exchange surfaces were revealed.

  18. CNDOL: A fast and reliable method for the calculation of electronic properties of very large systems. Applications to retinal binding pocket in rhodopsin and gas phase porphine.

    Science.gov (United States)

    Montero-Cabrera, Luis Alberto; Röhrig, Ute; Padrón-Garcia, Juan A; Crespo-Otero, Rachel; Montero-Alejo, Ana L; Garcia de la Vega, José M; Chergui, Majed; Rothlisberger, Ursula

    2007-10-14

    Very large molecular systems can be calculated with the so called CNDOL approximate Hamiltonians that have been developed by avoiding oversimplifications and only using a priori parameters and formulas from the simpler NDO methods. A new diagonal monoelectronic term named CNDOL/21 shows great consistency and easier SCF convergence when used together with an appropriate function for charge repulsion energies that is derived from traditional formulas. It is possible to obtain a priori molecular orbitals and electron excitation properties after the configuration interaction of single excited determinants with reliability, maintaining interpretative possibilities even being a simplified Hamiltonian. Tests with some unequivocal gas phase maxima of simple molecules (benzene, furfural, acetaldehyde, hexyl alcohol, methyl amine, 2,5 dimethyl 2,4 hexadiene, and ethyl sulfide) ratify the general quality of this approach in comparison with other methods. The calculation of large systems as porphine in gas phase and a model of the complete retinal binding pocket in rhodopsin with 622 basis functions on 280 atoms at the quantum mechanical level show reliability leading to a resulting first allowed transition in 483 nm, very similar to the known experimental value of 500 nm of "dark state." In this very important case, our model gives a central role in this excitation to a charge transfer from the neighboring Glu(-) counterion to the retinaldehyde polyene chain. Tests with gas phase maxima of some important molecules corroborate the reliability of CNDOL/2 Hamiltonians.

  19. Constrains on Crustal Accretion Obtained from Cooling Rate Calculations with a Thermo-Mechanical Model of Fast-Spreading Mid-Ocean Ridges

    Science.gov (United States)

    Garrido, C. J.; Machetel, P.

    2012-12-01

    We have used a thermo-mechanical model designed to find steady-state solutions of motion and temperature with variable viscosity, heat diffusion, heat advection, hydrothermal cooling and latent heat release. Cases analogous to the "gabbro glacier" (G accretion structure), "sheeted sills" (S structure) and "mixed shallow and MTZ lenses" (M structure) were computed with and without sheeted dyke level modeling. The results show that thermal patterns near the ridge mainly depend on hydrothermal cooling. Several hydrothermal cooling cracking temperature have been used in order to illustrate the present scientific debate on the penetration depth and efficiency of hydrothermal flows. Second, higher cooling rates are obtained for the G structures. Third, whereas the subsolidus cooling rates, SCR, decrease monotonically with depth, the igneous cooling rates, ICR, display local minima at the merging levels of the upper and lower lenses. It appears that ICR reveal the near-ridge thermal and mechanical structures, whereas the lower value of the initial-to-closure temperature ranges used for SCR cause shifts farther from the ridge that reduces the ability of SCR to discriminate the ridge thermo-mechanical configuration. It also indicates that the common assumption that ICR and SCR should be similar is probably over-simplified. Finally, the cooling rates obtained bears the clear signature of the three intrusion hypothesis. The results show that numerical modeling of the lower crust's thermo-mechanical properties may provide new insights to discriminate among hypotheses related to G, M and S structures for fast-spreading ridges.; Thermal history obtained for the Gabro Glacier (top panels), Mixed shallow and MTZ zone (middle panels) and Sheeted Sills hypothesis (bottom panels)for the magma intrusion at ridge. Columns corresponds to various hydrothermal cooling and viscosity hypothesis.

  20. 利用CUDA快速计算三角网格模型简化误差%Fast Calculating Simplification Error of Triangular Mesh Using CUDA

    Institute of Scientific and Technical Information of China (English)

    张衡; 唐杰; 武港山

    2011-01-01

    Propose a method to evaluate the overall simplification error of triangular meshes. It considers the contribution of all sample points to the error, which is more precise than the former methods that only consider the maximum error. Achieve a highly paralleled algorithrn to calculate the simplification error of triangular meshes by using CUDA. Uniform gird is adopted to manage triangles of each mesh to accelerate the space search speed. Proper data structure is designed to solve the problems such as CUDA does not support pointer, dynamically memory allocating and to avoid synchronization as much as possible. Finally, experimental results show the efficiency and effectiveness of this algorithm, which verify the advantages of GPU on high performance calculation compared to CPU.%提出从整体上考虑三角网格模TJ的简化误差的方法.该方法综合考虑了三角网格模型上所有采样点对误差的贡献,较以往方法只考虑最大误差更加准确.利用CUDA实现了高度并行化的网格模型简化误差计算算法.算法采用平均单元格来组织三角片,以便快速空间查询.同时设计了相应的数据结构,克服了CUDA没有指针、不能动态申请资源、尽量避免同步操作等问题.最后通过实验证明了本算法在速度和数据量上的优越性,并且阐述了GPU相对于CPU在高性能计算上的优点.

  1. Calculation for the fast axis beam quality of the laser diode stack%半导体激光器堆栈快轴光束质量计算的研究

    Institute of Scientific and Technical Information of China (English)

    李峙; 尧舜; 高祥宇; 潘飞; 贾冠男; 王智勇

    2015-01-01

    Based on the Gaussian beam propagation theory, and combined with the structure of the laser diode stack, the fast axis beam model of the laser diode stacks was established. And considered with the divergence angle and directional factor of each diode laser array, the calculation for the fast axis beam quality of the diode laser stacks was amended which was finally verified by the experiment. The result shows that compared with the experimental measurements, the calculation error of this model is only 2.14%. Compared with the ones before amending, which are 24.16% and 18.36%, the new calculation method is improved a lot in accuracy and can reflect the fast axis beam quality of diode laser stacks more exactitudly.%以高斯光束传输理论为基础,结合半导体激光器堆栈结构,建立了半导体激光器堆栈快轴方向光束传输理论模型,并引入单个半导体激光器阵列的发散角和指向性因子,对半导体激光器堆栈快轴方向光束质量计算方法进行了修正,最后通过实验对计算结果进行验证。结果显示,相对于实验测量值,该理论模型计算值的误差仅为2.14%,与修正前的计算误差24.16%和18.36%相比,在精度上有了很大程度的提高,因此,该方法可行,能更精确的反应堆栈快轴的光束质量。

  2. 适用于拓扑调整的短路电流快速计算方法%A method of fast short-circuit current calculation for topology adjustment

    Institute of Scientific and Technical Information of China (English)

    冯树海; 於益军; 王礼文; 石飞; 汤必强

    2014-01-01

    传统的适用于电网运行方式调整的短路电流计算方法耗时太长,无法满足电网快速分析决策的需求。在此背景下,提出了适用于电网拓扑调整的短路电流快速计算方法。该算法基于节点阻抗矩阵,采用补偿法分析发电机停运、线路开断和线路出串运行导致的阻抗矩阵变化,并在此基础上给出了适用于电网拓扑调整的短路电流快速计算流程。针对不同节点规模的实际系统的仿真算例表明,所提出的方法计算速度快,计算结果准确可靠,能够满足大电网方式调整优化对短路电流计算的要求。该方法可以为电网短路电流限制策略分析提供技术支撑。%The traditional method of the short-circuit current calculation, which is used for the operation mode arrangement, costs too much time. It cannot meet the demand of fast analysis and decision-making. Therefore, a fast algorithm of short-circuit current calculation that is applicable to the grid topology adjustment is put forward. Based on the node impedance matrix and compensation method, it can analyze the changes of impedance matrix caused by the generator outage, line outage and line out series, and based on which the calculation procedure is given. The performance of the proposed method is demonstrated by tests on several real power systems. The simulation results show that the proposed method is fast and accurate, and it can meet the demand of the operation mode arrangement of large-scale power systems. Furthermore, this method is able to provide the technical support for the measure analysis of the short-circuit current limitation.

  3. Ultra-fast calculations using diamond

    NARCIS (Netherlands)

    Van Dijk, T.

    2011-01-01

    TU Delft researchers have managed to use a piece of diamond to hold four quantum bits that can be spun, flipped and entangled with each other. This is an important step towards a working quantum computer

  4. A Fast Fractional Difference Algorithm

    DEFF Research Database (Denmark)

    Jensen, Andreas Noack; Nielsen, Morten Ørregaard

    We provide a fast algorithm for calculating the fractional difference of a time series. In standard implementations, the calculation speed (number of arithmetic operations) is of order T 2, where T is the length of the time series. Our algorithm allows calculation speed of order T logT . For mode......We provide a fast algorithm for calculating the fractional difference of a time series. In standard implementations, the calculation speed (number of arithmetic operations) is of order T 2, where T is the length of the time series. Our algorithm allows calculation speed of order T log...

  5. Forward Field Computation with OpenMEEG

    Directory of Open Access Journals (Sweden)

    Alexandre Gramfort

    2011-01-01

    must be computed. We present OpenMEEG, which solves the electromagnetic forward problem in the quasistatic regime, for head models with piecewise constant conductivity. The core of OpenMEEG consists of the symmetric Boundary Element Method, which is based on an extended Green Representation theorem. OpenMEEG is able to provide lead fields for four different electromagnetic forward problems: Electroencephalography (EEG, Magnetoencephalography (MEG, Electrical Impedance Tomography (EIT, and intracranial electric potentials (IPs. OpenMEEG is open source and multiplatform. It can be used from Python and Matlab in conjunction with toolboxes that solve the inverse problem; its integration within FieldTrip is operational since release 2.0.

  6. Forward Field Computation with OpenMEEG

    OpenAIRE

    2011-01-01

    To recover the sources giving rise to electro- and magnetoencephalography in individual measurements, realistic physiological modeling is required, and accurate numerical solutions must be computed. We present OpenMEEG, which solves the electromagnetic forward problem in the quasistatic regime, for head models with piecewise constant conductivity. The core of OpenMEEG consists of the symmetric Boundary Element Method, which is based on an extended Green Representation theorem. OpenMEEG is abl...

  7. Forward field computation with OpenMEEG.

    Science.gov (United States)

    Gramfort, Alexandre; Papadopoulo, Théodore; Olivi, Emmanuel; Clerc, Maureen

    2011-01-01

    To recover the sources giving rise to electro- and magnetoencephalography in individual measurements, realistic physiological modeling is required, and accurate numerical solutions must be computed. We present OpenMEEG, which solves the electromagnetic forward problem in the quasistatic regime, for head models with piecewise constant conductivity. The core of OpenMEEG consists of the symmetric Boundary Element Method, which is based on an extended Green Representation theorem. OpenMEEG is able to provide lead fields for four different electromagnetic forward problems: Electroencephalography (EEG), Magnetoencephalography (MEG), Electrical Impedance Tomography (EIT), and intracranial electric potentials (IPs). OpenMEEG is open source and multiplatform. It can be used from Python and Matlab in conjunction with toolboxes that solve the inverse problem; its integration within FieldTrip is operational since release 2.0.

  8. 中国实验快堆全堆芯流量分配计算与试验%Calculation and Test of Core Flow Rate Distribution of China Experimental Fast Reactor

    Institute of Scientific and Technical Information of China (English)

    刘一哲; 薛秀丽; 许义军; 冯预恒; 侯志峰

    2012-01-01

    Based on the core and primary circuit design of China Experimental Fast Reactor(CEFR), a multiple-channel thermal-hydraulic analysis code DAEMON was developed to calculate the core flow rate distribution and unsymmetric coefficient in different conditions. In the commissioning stage, a series of full-scale tests for reactor core were performed in CEFR with a permanent-magnet sodium flow meter. The numerical results of code DAEMON showed a good agreement with test data. The core hydraulic design was also validated with a view to the requirements of design criteria, commissioning and operation specifications.%针对中国实验快堆(CEFR)堆芯和一回路的设计特点,开发水力特性计算程序DAEMON,完成不同工况下的全堆芯流量分配计算,给出流量分配不均匀性等参数.在反应堆调试阶段,进行全堆芯流量分配试验.结果表明,程序计算值与试验值符合较好.在此基础上,验证了CEFR堆芯的流体力学设计,并为反应堆调试和运行提供了基础数据.

  9. Fast Calculation of Protein Molecular Field and Its Application on Protein Recog-nition Research%分子场快速计算及在蛋白质识别研究中的应用

    Institute of Scientific and Technical Information of China (English)

    张繁; 王章野; 吴韬; 彭群生

    2013-01-01

      蛋白质识别关键区域的研究对揭示生命现象的本质规律,提高药物设计效率,降低新药物开发的成本和周期有重大的应用价值。但由于蛋白质大分子结构的高度复杂性,一般的计算机系统难以对蛋白质识别过程中结构与功能的连续性变化实现快速动态分析。设计并实现了一种基于GPU/CPU异构的集群系统,根据生物计算的特点对异构集群进行数据结构和算法设计,建立起基于GPU的Kd-tree构造和访问的高效算法,以提高系统并行计算的性能。在此基础上对蛋白质分子场的动态时变序列进行快速计算,对结果进行分类,能快速高效地确定出蛋白质的相互作用关键区域。该方法得到了相应的生化实验结果验证,为揭示蛋白质作用机制提供了一种高效直观的新方法。%It has been found that key area research during protein recognition process is typically important for proclaiming biological phenomena essence, improving drug design efficiency and decreasing cost and shortening industrial cycle of new drug design. For high complexity of protein macromolecule structure, common computer systems are not capable for continuously tracking coherence change of structure and function during protein recognition. This paper sets up a heterogeneous cluster based on GPU/CPU as a uniform biological computing environment, proposes particular data structures and algorithms to deal with large biological data, and reconfigures Kd-tree based on GPU and data access modes to improve parallel calculation performance. Thus it becomes feasible to calculate time-varying protein molecular filed fast enough to do further analysis on key area for protein recognition. The corresponding biochemistry experiment results show that the method can be used as a new effective and intuitive tool for protein interaction research.

  10. Methods of Fast Exponentiation

    Directory of Open Access Journals (Sweden)

    Mohammed A. Maitah

    2010-01-01

    Full Text Available Problem statement: Modular exponentiation constitutes the basis of many well-known and widely used public key cryptosystems. Approach: A fast portable modular exponentiation algorithm considerably enhanced the speed and applicability of these systems, also an efficient implementation of this algorithm was the key to high performance of such system. Results: In this study, two main approaches for solving this problem were proposed. The proposed approaches involved calculations without usage of extra operational memory for saving constants and calculations with usage of preliminary calculated constants. Conclusion/Recommendations: The estimation of complexity of the speedup and effectiveness of proposed approaches for the data were presented.

  11. The fast code

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, L.N.; Wilson, R.E. [Oregon State Univ., Dept. of Mechanical Engineering, Corvallis, OR (United States)

    1996-09-01

    The FAST Code which is capable of determining structural loads on a flexible, teetering, horizontal axis wind turbine is described and comparisons of calculated loads with test data are given at two wind speeds for the ESI-80. The FAST Code models a two-bladed HAWT with degrees of freedom for blade bending, teeter, drive train flexibility, yaw, and windwise and crosswind tower motion. The code allows blade dimensions, stiffnesses, and weights to differ and models tower shadow, wind shear, and turbulence. Additionally, dynamic stall is included as are delta-3 and an underslung rotor. Load comparisons are made with ESI-80 test data in the form of power spectral density, rainflow counting, occurrence histograms, and azimuth averaged bin plots. It is concluded that agreement between the FAST Code and test results is good. (au)

  12. Declination Calculator

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Declination is calculated using the current International Geomagnetic Reference Field (IGRF) model. Declination is calculated using the current World Magnetic Model...

  13. INVAP's Nuclear Calculation System

    Directory of Open Access Journals (Sweden)

    Ignacio Mochi

    2011-01-01

    Full Text Available Since its origins in 1976, INVAP has been on continuous development of the calculation system used for design and optimization of nuclear reactors. The calculation codes have been polished and enhanced with new capabilities as they were needed or useful for the new challenges that the market imposed. The actual state of the code packages enables INVAP to design nuclear installations with complex geometries using a set of easy-to-use input files that minimize user errors due to confusion or misinterpretation. A set of intuitive graphic postprocessors have also been developed providing a fast and complete visualization tool for the parameters obtained in the calculations. The capabilities and general characteristics of this deterministic software package are presented throughout the paper including several examples of its recent application.

  14. Usefulness of non-fasting lipid parameters in children.

    Science.gov (United States)

    Kubo, Toshihide; Takahashi, Kyohei; Furujo, Mahoko; Hyodo, Yuki; Tsuchiya, Hiroki; Hattori, Mariko; Fujinaga, Shoko; Urayama, Kenji

    2017-01-01

    This study assessed whether non-fasting lipid markers could be substituted for fasting markers in screening for dyslipidemia, whether direct measurement of non-fasting low-density lipoprotein cholesterol [LDL-C (D)] could be substituted for the calculation of fasting LDL-C [LDL-C (F)], and the utility of measuring non-high-density lipoprotein cholesterol (non-HDL-C). In 33 children, the lipid profile was measured in the non-fasting and fasting states within 24 h. Correlations were examined between non-fasting LDL-C (D) or non-HDL-C levels and fasting LDL-C (F) levels. Non-fasting triglyceride (TG), total cholesterol (TC), HDL-C, LDL-C (D), and non-HDL-C levels were all significantly higher than the fasting levels, but the mean difference was within 10% (except for TG). Non-fasting LDL-C (D) and non-HDL-C levels were strongly correlated with the fasting LDL-C (F) levels. In conclusion, except for TG, non-fasting lipid parameters are useful when screening children for dyslipidemia. Direct measurement of non-fasting LDL-C and calculation of non-fasting non-HDL-C could replace the calculation of fasting LDL-C because of convenience.

  15. Proceedings of the NEACRP/IAEA Specialists meeting on the international comparison calculation of a large sodium-cooled fast breeder reactor at Argonne National Laboratory on February 7-9, 1978

    Energy Technology Data Exchange (ETDEWEB)

    LeSage, L.G.; McKnight, R.D.; Wade, D.C.; Freese, K.E.; Collins, P.J.

    1980-08-01

    The results of an international comparison calculation of a large (1250 MWe) LMFBR benchmark model are presented and discussed. Eight reactor configurations were calculated. Parameters included with the comparison were: eigenvalue, k/sub infinity/, neutron balance data, breeding reaction rate ratios, reactivity worths, central control rod worth, regional sodium void reactivity, core Doppler and effective delayed neutron fraction. Ten countries participated in the comparison, and sixteen solutions were contributed. The discussion focuses on the variation in parameter values, the degree of consistency among the various parameters and solutions, and the identification of unexpected results. The results are displayed and discussed both by individual participants and by groupings of participants (e.g., results from adjusted data sets versus non-adjusted data sets).

  16. Research on Fast Calculation Method of Waste Heat Recovery Unit of Kiln%水泥窑筒体余热回收装置快速计算方法研究

    Institute of Scientific and Technical Information of China (English)

    赵艳玲; 耿亮

    2014-01-01

    The quantity of heat transfer on waste heat recovery unit of kiln has been analyzed with the finite differ-ence method,and Microsoft Excellwas used as the computational tools.Through verification of an engineering case, the calculation tables have reliable precision and high efficiency.%利用有限差分法对窑筒体余热回收装置换热量进行分析,提出了通过 Excel 计算表格进行余热回收装置工况分析的方法。通过工程实例验证,编制的计算表格具有精度可靠、效率高的优点。

  17. Fast breeder reactors an engineering introduction

    CERN Document Server

    Judd, A M

    1981-01-01

    Fast Breeder Reactors: An Engineering Introduction is an introductory text to fast breeder reactors and covers topics ranging from reactor physics and design to engineering and safety considerations. Reactor fuels, coolant circuits, steam plants, and control systems are also discussed. This book is comprised of five chapters and opens with a brief summary of the history of fast reactors, with emphasis on international and the prospect of making accessible enormous reserves of energy. The next chapter deals with the physics of fast reactors and considers calculation methods, flux distribution,

  18. 基于快速蒙特卡罗的散射介质光学参量干涉测量方法研究%Reverse Calculation of Optical Parameters of Scattering Medium Based on Fast Monte Carlo Simulation

    Institute of Scientific and Technical Information of China (English)

    张梅; 林林; 高应俊; 罗云瀚

    2012-01-01

    A method of coherent measuring optical parameters of scattering medium is presented based on Monte Carlo simulation. The condensed scaling method is introduced to accelerating process of calculation. A tri-layer structure BP-artificial neural network is developed for reverse calculation of scattering and absorption coefficients of medium. Fat emulsion and stain mixture of IntralipidTM and India ink are taken as scattering and absorbing sample for coherent measurement by fiber Michelson interferometer. Results of experiments show the linear relation between scattering or absorption coefficients and concentration of IntralipidTM or India ink. The method is helpful to nondestructive testing components of turbid material.%提出了一种散射介质光学参量的干涉测量方法.在蒙特卡罗数值模拟的基础上引入聚焦高斯光源模型和基于比例缩放的压缩算法,实现了对光子后向散射分布和干涉特性的快速模拟.利用计算数据训练了前向人工神经网络进行了介质光学参量的反向求解.实验中以脂肪乳注射剂和生物染色剂印度墨水组成的悬混液为样本,通过光学干涉系统测量得到了后向散射光依赖于深度的干涉光强分布,并对其中散射和吸收系数进行了反向计算.所得结果能够正确反映散射和吸收系数与散射和吸收物质浓度之间的线性关系,验证了该方法的可行性.

  19. Equilibrium calculations of firework mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, M.L. [Sandia National Labs., Albuquerque, NM (United States); Tanaka, Katsumi; Iida, Mitsuaki; Matsunaga, Takehiro [National Inst. of Materials and Chemical Research, Tsukuba, Ibaraki (Japan)

    1994-12-31

    Thermochemical equilibrium calculations have been used to calculate detonation conditions for typical firework components including three report charges, two display charges, and black powder which is used as a fuse or launch charge. Calculations were performed with a modified version of the TIGER code which allows calculations with 900 gaseous and 600 condensed product species at high pressure. The detonation calculations presented in this paper are thought to be the first report on the theoretical study of firework detonation. Measured velocities for two report charges are available and compare favorably to predicted detonation velocities. However, the measured velocities may not be true detonation velocities. Fast deflagration rather than an ideal detonation occurs when reactants contain significant amounts of slow reacting constituents such as aluminum or titanium. Despite such uncertainties in reacting pyrotechnics, the detonation calculations do show the complex nature of condensed phase formation at elevated pressures and give an upper bound for measured velocities.

  20. Calculator calculus

    CERN Document Server

    McCarty, George

    1982-01-01

    How THIS BOOK DIFFERS This book is about the calculus. What distinguishes it, however, from other books is that it uses the pocket calculator to illustrate the theory. A computation that requires hours of labor when done by hand with tables is quite inappropriate as an example or exercise in a beginning calculus course. But that same computation can become a delicate illustration of the theory when the student does it in seconds on his calculator. t Furthermore, the student's own personal involvement and easy accomplishment give hi~ reassurance and en­ couragement. The machine is like a microscope, and its magnification is a hundred millionfold. We shall be interested in limits, and no stage of numerical approximation proves anything about the limit. However, the derivative of fex) = 67.SgX, for instance, acquires real meaning when a student first appreciates its values as numbers, as limits of 10 100 1000 t A quick example is 1.1 , 1.01 , 1.001 , •••• Another example is t = 0.1, 0.01, in the functio...

  1. Development of a computer program of fast calculation for the pre design of advanced nuclear fuel 10 x 10 for BWR type reactors; Desarrollo de un program de computo de calculo rapido para el prediseno de celdas de combustible nuclear avanzado 10 x 10 para reactores de agua en ebullicion

    Energy Technology Data Exchange (ETDEWEB)

    Perusquia, R.; Montes, J.L.; Ortiz, J.J. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: mrpc@nuclear.inin.mx

    2005-07-01

    In the National Institute of Nuclear Research (ININ) a methodology is developed to optimize the design of cells 10x10 of assemble fuels for reactors of water in boil or BWR. It was proposed a lineal calculation formula based on a coefficients matrix (of the change reason of the relative power due to changes in the enrichment of U-235) for estimate the relative powers by pin of a cell. With this it was developed the computer program of fast calculation named PreDiCeldas. The one which by means of a simple search algorithm allows to minimize the relative power peak maximum of cell or LPPF. This is achieved varying the distribution of U-235 inside the cell, maintaining in turn fixed its average enrichment. The accuracy in the estimation of the relative powers for pin is of the order from 1.9% when comparing it with results of the 'best estimate' HELIOS code. With the PreDiCeldas it was possible, at one minimum time of calculation, to re-design a reference cell diminishing the LPPF, to the beginning of the life, of 1.44 to a value of 1.31. With the cell design with low LPPF is sought to even design cycles but extensive that those reached at the moment in the BWR of the Laguna Verde Central. (Author)

  2. Current status of fast reactor physics

    Energy Technology Data Exchange (ETDEWEB)

    Hummel, H.H.

    1979-01-01

    The subject of calculation of reactivity coefficients for fast reactors is developed, starting with a discussion of the status of relevant nuclear data and proceeding to the subjects of group cross section generation and of methods of obtaining reactivity coefficients from group cross sections. Reactivity coefficients measured in critical experiments are compared with calculated values. Dependence of reactivity coefficients on reactor design is discussed. Finally, results of the recent international comparison of calculated reactivity coefficients are presented.

  3. HCUP Fast Stats

    Data.gov (United States)

    U.S. Department of Health & Human Services — HCUP Fast Stats provides easy access to the latest HCUP-based statistics for health information topics. HCUP Fast Stats uses visual statistical displays in...

  4. Fast food (image)

    Science.gov (United States)

    Fast foods are quick, reasonably priced, and readily available alternatives to home cooking. While convenient and economical for a busy lifestyle, fast foods are typically high in calories, fat, saturated ...

  5. Fast food tips (image)

    Science.gov (United States)

    ... challenge to eat healthy when going to a fast food place. In general, avoiding items that are deep ... challenge to eat healthy when going to a fast food place. In general, avoiding items that are deep ...

  6. Is fast food addictive?

    Science.gov (United States)

    Garber, Andrea K; Lustig, Robert H

    2011-09-01

    Studies of food addiction have focused on highly palatable foods. While fast food falls squarely into that category, it has several other attributes that may increase its salience. This review examines whether the nutrients present in fast food, the characteristics of fast food consumers or the presentation and packaging of fast food may encourage substance dependence, as defined by the American Psychiatric Association. The majority of fast food meals are accompanied by a soda, which increases the sugar content 10-fold. Sugar addiction, including tolerance and withdrawal, has been demonstrated in rodents but not humans. Caffeine is a "model" substance of dependence; coffee drinks are driving the recent increase in fast food sales. Limited evidence suggests that the high fat and salt content of fast food may increase addictive potential. Fast food restaurants cluster in poorer neighborhoods and obese adults eat more fast food than those who are normal weight. Obesity is characterized by resistance to insulin, leptin and other hormonal signals that would normally control appetite and limit reward. Neuroimaging studies in obese subjects provide evidence of altered reward and tolerance. Once obese, many individuals meet criteria for psychological dependence. Stress and dieting may sensitize an individual to reward. Finally, fast food advertisements, restaurants and menus all provide environmental cues that may trigger addictive overeating. While the concept of fast food addiction remains to be proven, these findings support the role of fast food as a potentially addictive substance that is most likely to create dependence in vulnerable populations.

  7. Fast Calculation of the Weak Lensing Aperture Mass Statistic

    CERN Document Server

    Leonard, Adrienne; Starck, Jean-Luc

    2012-01-01

    The aperture mass statistic is a common tool used in weak lensing studies. By convolving lensing maps with a filter function of a specific scale, chosen to be larger than the scale on which the noise is dominant, the lensing signal may be boosted with respect to the noise. This allows for detection of structures at increased fidelity. Furthermore, higher-order statistics of the aperture mass (such as its skewness or kurtosis), or counting of the peaks seen in the resulting aperture mass maps, provide a convenient and effective method to constrain the cosmological parameters. In this paper, we more fully explore the formalism underlying the aperture mass statistic. We demonstrate that the aperture mass statistic is formally identical to a wavelet transform at a specific scale. Further, we show that the filter functions most frequently used in aperture mass studies are not ideal, being non-local in both real and Fourier space. In contrast, the wavelet formalism offers a number of wavelet functions that are loca...

  8. Calculation of minimum miscibility pressure using fast slimtube simulation

    DEFF Research Database (Denmark)

    Yan, Wei; Michelsen, Michael Locht; Stenby, Erling Halfdan

    2012-01-01

    and determines the MMP from the recovery-pressure curve, just as in the experiment. The global approach, which is based on the method of characteristics analysis of 1D gas injection, finds the MMP by locating the pressure where a key tie-line becomes critical. Although the global approach is faster, the slimtube...

  9. Fast heat transfer calculations in supercritical fluids versus hydrodynamic approach

    CERN Document Server

    Nikolayev, Vadim; Garrabos, Y; Beysens, D

    2016-01-01

    This study investigates the heat transfer in a simple pure fluid whose temperature is slightly above its critical temperature. We propose a efficient numerical method to predict the heat transfer in such fluids when the gravity can be neglected. The method, based on a simplified thermodynamic approach, is compared with direct numerical simulations of the Navier-Stokes and energy equations performed for CO2 and SF6. A realistic equation of state is used to describe both fluids. The proposed method agrees with the full hydrodynamic solution and provides a huge gain in computation time. The connection between the purely thermodynamic and hydrodynamic descriptions is also discussed.

  10. Enhanced Model for Fast Ignition

    Energy Technology Data Exchange (ETDEWEB)

    Mason, Rodney J. [Research Applications Corporation, Los Alamos, NM (United States)

    2010-10-12

    Laser Fusion is a prime candidate for alternate energy production, capable of serving a major portion of the nation's energy needs, once fusion fuel can be readily ignited. Fast Ignition may well speed achievement of this goal, by reducing net demands on laser pulse energy and timing precision. However, Fast Ignition has presented a major challenge to modeling. This project has enhanced the computer code ePLAS for the simulation of the many specialized phenomena, which arise with Fast Ignition. The improved code has helped researchers to understand better the consequences of laser absorption, energy transport, and laser target hydrodynamics. ePLAS uses efficient implicit methods to acquire solutions for the electromagnetic fields that govern the accelerations of electrons and ions in targets. In many cases, the code implements fluid modeling for these components. These combined features, "implicitness and fluid modeling," can greatly facilitate calculations, permitting the rapid scoping and evaluation of experiments. ePLAS can be used on PCs, Macs and Linux machines, providing researchers and students with rapid results. This project has improved the treatment of electromagnetics, hydrodynamics, and atomic physics in the code. It has simplified output graphics, and provided new input that avoids the need for source code access by users. The improved code can now aid university, business and national laboratory users in pursuit of an early path to success with Fast Ignition.

  11. Ramadan, fasting and pregnancy

    DEFF Research Database (Denmark)

    Ahmed, Urfan Zahoor; Lykke, Jacob Alexander

    2014-01-01

    In Islam, the month of Ramadan is a period of fasting lasting 29 or 30 days. Epidemiological studies among Muslims in Denmark have not been conducted, but studies show, that fasting among pregnant Muslim women is common. Fasting does not increase the risk of growth restriction or preterm delivery......, but there are reports of decreased foetal movements. Furthermore, the fasting may have long-term health consequences for the offspring, especially when they reach their middle age. According to Islam and the interpretation, pregnant and breast-feeding women are allowed to postpone the fasting of the month of Ramadan...

  12. Integrative Physiology of Fasting.

    Science.gov (United States)

    Secor, Stephen M; Carey, Hannah V

    2016-03-15

    Extended bouts of fasting are ingrained in the ecology of many organisms, characterizing aspects of reproduction, development, hibernation, estivation, migration, and infrequent feeding habits. The challenge of long fasting episodes is the need to maintain physiological homeostasis while relying solely on endogenous resources. To meet that challenge, animals utilize an integrated repertoire of behavioral, physiological, and biochemical responses that reduce metabolic rates, maintain tissue structure and function, and thus enhance survival. We have synthesized in this review the integrative physiological, morphological, and biochemical responses, and their stages, that characterize natural fasting bouts. Underlying the capacity to survive extended fasts are behaviors and mechanisms that reduce metabolic expenditure and shift the dependency to lipid utilization. Hormonal regulation and immune capacity are altered by fasting; hormones that trigger digestion, elevate metabolism, and support immune performance become depressed, whereas hormones that enhance the utilization of endogenous substrates are elevated. The negative energy budget that accompanies fasting leads to the loss of body mass as fat stores are depleted and tissues undergo atrophy (i.e., loss of mass). Absolute rates of body mass loss scale allometrically among vertebrates. Tissues and organs vary in the degree of atrophy and downregulation of function, depending on the degree to which they are used during the fast. Fasting affects the population dynamics and activities of the gut microbiota, an interplay that impacts the host's fasting biology. Fasting-induced gene expression programs underlie the broad spectrum of integrated physiological mechanisms responsible for an animal's ability to survive long episodes of natural fasting.

  13. 行星差动轮系功率分流和传动比的内在规律及速算法%Inherent Laws and Fast Calculation Method of Power Dividing and Transmission Ratio of Planetary Differential Gear Train

    Institute of Scientific and Technical Information of China (English)

    冯仲

    2012-01-01

    以履带式行走机构的三级行星差动轮系为例,用解析法分别推导该机构功率分流、传动比通式,并揭示差动行星机构功率分流与传动比的内在规律及速算法,通过进一步说明,提出差动行星机构的串、并联关系,将差动行星轮系简化成一般行星轮系.%Taking the three planetary differential gear train of crawler walking mechanism as an example, the mechanism power dividing and transmission ratio formula are derived by analytical method,the inherent laws and fast calculation method of planetary differential gear train power dividing and transmission ratio are revealed. By further explanation , the serial connection and parallel connection of planetary differential gear train is proposed, planetary differential gear train to general planetary gear train is simplified.

  14. Fast growth in control

    NARCIS (Netherlands)

    Z. Rico (Zulay)

    2009-01-01

    textabstractThe focus of this paper is on the influence of the fast growth of organizations on the design process of management control systems. What are the management accounting and control problems that a fast growth organization encounters that can be ascribed to this growth. What are the circum

  15. Fast protein folding kinetics

    Science.gov (United States)

    Gelman, Hannah; Gruebele, Martin

    2014-01-01

    Fast folding proteins have been a major focus of computational and experimental study because they are accessible to both techniques: they are small and fast enough to be reasonably simulated with current computational power, but have dynamics slow enough to be observed with specially developed experimental techniques. This coupled study of fast folding proteins has provided insight into the mechanisms which allow some proteins to find their native conformation well less than 1 ms and has uncovered examples of theoretically predicted phenomena such as downhill folding. The study of fast folders also informs our understanding of even “slow” folding processes: fast folders are small, relatively simple protein domains and the principles that govern their folding also govern the folding of more complex systems. This review summarizes the major theoretical and experimental techniques used to study fast folding proteins and provides an overview of the major findings of fast folding research. Finally, we examine the themes that have emerged from studying fast folders and briefly summarize their application to protein folding in general as well as some work that is left to do. PMID:24641816

  16. Ramadan, faste og graviditet

    DEFF Research Database (Denmark)

    Ahmed, Urfan Zahoor; Lykke, Jacob Alexander

    2014-01-01

    , but there are reports of decreased foetal movements. Furthermore, the fasting may have long-term health consequences for the offspring, especially when they reach their middle age. According to Islam and the interpretation, pregnant and breast-feeding women are allowed to postpone the fasting of the month of Ramadan...

  17. Fast protein folding kinetics.

    Science.gov (United States)

    Gelman, Hannah; Gruebele, Martin

    2014-05-01

    Fast-folding proteins have been a major focus of computational and experimental study because they are accessible to both techniques: they are small and fast enough to be reasonably simulated with current computational power, but have dynamics slow enough to be observed with specially developed experimental techniques. This coupled study of fast-folding proteins has provided insight into the mechanisms, which allow some proteins to find their native conformation well fast folders also informs our understanding of even 'slow' folding processes: fast folders are small; relatively simple protein domains and the principles that govern their folding also govern the folding of more complex systems. This review summarizes the major theoretical and experimental techniques used to study fast-folding proteins and provides an overview of the major findings of fast-folding research. Finally, we examine the themes that have emerged from studying fast folders and briefly summarize their application to protein folding in general, as well as some work that is left to do.

  18. Fast ejendom III

    DEFF Research Database (Denmark)

    Munk-Hansen, Carsten

    Bogen er det tredje bind af tre planlagte bind om fast ejendom: I Overdragelsen, II Bolighandlen og III Ejerbeføjelsen. Fremstillingens giver et grundigt overblik over centrale områder af en omfattende regulering af fast ejendom, med angivelse af litteratur, hvor læseren kan søge yderligere...... oplysning. En ejer af fast ejendom er på særdeles mange områder begrænset i sin råden sammenlignet med ejeren af et formuegode i almindelighed. Fremstillingen tager udgangspunkt i ejerens perspektiv (fremfor samfundets eller myndighedernes). Både den privatretlige og offentligretlige regulering behandles......, eksempelvis ejendomsdannelsen, servitutter, naboretten, hævd, zoneinddelingen, den fysiske planlægning, beskyttelse af natur, beskyttelse af kultur, forurening fra fast ejendom, erstatning for forurening, jordforurening, ekspropriation, byggeri og adgang til fast ejendom....

  19. Islamic Fasting and Diabetes

    Directory of Open Access Journals (Sweden)

    Fereidoun Azizi

    2013-07-01

    Full Text Available The aim of this article is to review health-related aspects of Ramadan fasting in normal individuals and diabetics. During fasting days of Ramadan, glucose homeostasis is maintained by meal taken bepore dawn and by liver glycogen stores. Changes in serum lipids are variable and defend on the quality and quantity of food consumption and changes in weight. Compliant, well controlled type 2 diabetics may observe Ramadan fasting; but fasting is not recommended for type 1, non complaint, poorly controlled and pregnant diabetics. Although Ramadan fasting is safe for all healthy individuals and well controlled diabetics, those with uncontrolled diabetics and diabetics with complications should consult physicians and follow scientific recommendations.

  20. Fast Spectrum Reactors

    CERN Document Server

    Todd, Donald; Tsvetkov, Pavel

    2012-01-01

    Fast Spectrum Reactors presents a detailed overview of world-wide technology contributing to the development of fast spectrum reactors. With a unique focus on the capabilities of fast spectrum reactors to address nuclear waste transmutation issues, in addition to the well-known capabilities of breeding new fuel, this volume describes how fast spectrum reactors contribute to the wide application of nuclear power systems to serve the global nuclear renaissance while minimizing nuclear proliferation concerns. Readers will find an introduction to the sustainable development of nuclear energy and the role of fast reactors, in addition to an economic analysis of nuclear reactors. A section devoted to neutronics offers the current trends in nuclear design, such as performance parameters and the optimization of advanced power systems. The latest findings on fuel management, partitioning and transmutation include the physics, efficiency and strategies of transmutation, homogeneous and heterogeneous recycling, in addit...

  1. Fast neutron flux calculation benchmark analysis of PWR pressure vessel based on 3D MC-SN coupled method%基于三维MC-SN耦合方法的PWR压力容器快中子注量计算基准分析

    Institute of Scientific and Technical Information of China (English)

    韩静茹; 陈义学; 石生春; 袁龙军; 陆道纲

    2012-01-01

    The Monte Carlo (MC)-discrete ordinates (SN) coupled method is an efficient approach to solve shielding calculations of nuclear device with complex geometries and deep penetration. The 3D MC-SN coupled method has been used for PWR shielding calculation for the first time. According to characteristics of NUREG/CR-6115 PWR model, the thermal shield is specified as the common surface to link the Monte Carlo complex geometrical model and the deep penetration SN model. 3D Monte Carlo code is employed to accurately simulate the structure from core to thermal shield. The neutron tracks crossing the thermal shield inner surface are recorded by MC code. The SN boundary source is generated by the interface program and used by the 3D SN code to treat the calculation from thermal shield to pressure vessel. The calculation results include the circular distributions of fast neutron flux at pressure vessel inner wall, pressure vessel T/4 and lower weld locations. The calculation results are performed with comparison to MCNP and DORT solutions of benchmark report and satisfactory agreements are obtained. The validity of the method and the correctness of the programs are proved.%蒙特卡罗(MC)-离散纵标(SN)耦合方法是解决同时具有复杂几何和深穿透特点的核装置屏蔽问题的有效方法.本文首次将三维MC-SN耦合方法应用于压水堆屏蔽计算.针对NUREG/CR-6115压水堆基准模型,选取热屏蔽内表面为公共交界面,将其分为几何复杂的MC模拟区和具有深穿透特点的SN模拟区.三维MC程序用于精确描述堆芯到热屏蔽精细模型,并记录穿过热屏蔽内表面的中子径迹信息.接口程序将中子径迹转换为SN计算所需的边界源,提供给三维SN程序进行热屏蔽到压力容器的计算.计算结果包括压力容器内表面、1/4壁厚处及焊缝处快中子注量(E>1.0 MeV)圆周方向分布.三维耦合方法计算结果与基准报告提供的MCNP、DORT结果符合良好,验证了

  2. Modern Feynman Diagrammatic One-Loop Calculations

    CERN Document Server

    Reiter, Thomas; Greiner, Nicolas; Guffanti, Alberto; Guillet, Jean-Philippe; Heinrich, Gudrun; Karg, Stefan; Kauer, Nikolas; Kleinschmidt, Tobias; Koch-Janusz, Maciej; Luisoni, Gionata; Mastrolia, Pierpaolo; Ossola, Giovanni; Pilon, Eric; Rodgers, Mark; Tramontano, Francesco; Wigmore, Ioan

    2010-01-01

    In this talk we present techniques for calculating one-loop amplitudes for multi-leg processes using Feynman diagrammatic methods in a semi-algebraic context. Our approach combines the advantages of the different methods allowing for a fast evaluation of the amplitude while monitoring the numerical stability of the calculation. In phase space regions close to singular kinematics we use a method avoiding spurious Gram determinants in the calculation. As an application of our approach we report on the status of the calculation of the amplitude for the process $pp\\to b\\bar{b}b\\bar{b}+X$.

  3. FAST Construction Progress

    Science.gov (United States)

    Nan, R. D.; Zhang, H. Y.; Zhang, Y.; Yang, L.; Cai, W. J.; Liu, N.; Xie, J. T.; Zhang, S. X.

    2016-11-01

    The Five-hundred-meter Aperture Spherical radio Telescope (FAST) is a Chinese mega-science project to build the largest single dish radio telescope in the world. A unique karst depression in Guizhou province has been selected as the site to build an active reflector radio telescope with a diameter of 500 m and three outstanding aspects, which enables FAST to have a large sky coverage and the ability of observing astronomical targets with a high precision. Chinese Academy of Sciences and Guizhou province are in charge of FAST construction. The first light of the telescope was expected on September 25, 2016.

  4. Fast Breeder Reactor studies

    Energy Technology Data Exchange (ETDEWEB)

    Till, C.E.; Chang, Y.I.; Kittel, J.H.; Fauske, H.K.; Lineberry, M.J.; Stevenson, M.G.; Amundson, P.I.; Dance, K.D.

    1980-07-01

    This report is a compilation of Fast Breeder Reactor (FBR) resource documents prepared to provide the technical basis for the US contribution to the International Nuclear Fuel Cycle Evaluation. The eight separate parts deal with the alternative fast breeder reactor fuel cycles in terms of energy demand, resource base, technical potential and current status, safety, proliferation resistance, deployment, and nuclear safeguards. An Annex compares the cost of decommissioning light-water and fast breeder reactors. Separate abstracts are included for each of the parts.

  5. Gas cooled fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1972-06-01

    Although most of the development work on fast breeder reactors has been devoted to the use of liquid metal cooling, interest has been expressed for a number of years in alternative breeder concepts using other coolants. One of a number of concepts in which interest has been retained is the Gas-Cooled Fast Reactor (GCFR). As presently envisioned, it would operate on the uranium-plutonium mixed oxide fuel cycle, similar to that used in the Liquid Metal Fast Breeder Reactor (LMFBR), and would use helium gas as the coolant.

  6. Realistic level density calculation for heavy nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Cerf, N. [Institut de Physique Nucleaire, Orsay (France); Pichon, B. [Observatoire de Paris, Meudon (France); Rayet, M.; Arnould, M. [Institut d`Astronomie et d`Astrophysique, Bruxelles (Belgium)

    1994-12-31

    A microscopic calculation of the level density is performed, based on a combinatorial evaluation using a realistic single-particle level scheme. This calculation relies on a fast Monte Carlo algorithm, allowing to consider heavy nuclei (i.e., large shell model spaces) which could not be treated previously in combinatorial approaches. An exhaustive comparison of the predicted neutron s-wave resonance spacings with experimental data for a wide range of nuclei is presented.

  7. FAST joins Breakthrough programme

    Science.gov (United States)

    Banks, Michael

    2016-11-01

    The 180m Five-hundred-meter Aperture Spherical radio Telescope (FAST) - the world's largest single-aperture radio receiver - has become part of the Breakthrough Listen programme, which launched in July 2015 to look for intelligent life beyond Earth.

  8. CMS Fast Facts

    Data.gov (United States)

    U.S. Department of Health & Human Services — CMS has developed a new quick reference statistical summary on annual CMS program and financial data. CMS Fast Facts includes summary information on total program...

  9. FAST Maser Surveys

    Indian Academy of Sciences (India)

    J. S. Zhang

    2014-09-01

    FAST, the Five-hundred meter Aperture Spherical radio Telescope, will become the largest operating single-dish telescope in the coming years. It has many advantages: much better sensitivity for its largest collecting area; large sky coverage due to its innovative design of the active primary surface; extremely radio quiet from its unique location, etc. In this work, I will highlight the future capabilities of FAST to discover and observe both galactic and extragalactic masers.

  10. Fasting and Urinary Stones

    Directory of Open Access Journals (Sweden)

    Ali Shamsa

    2013-11-01

    Full Text Available Introduction: Fasting is considered as one of the most important practices of Islam, and according to Prophet Mohammad, fasting is obligatory upon Muslims. The aim of this study is to evaluate the effects of fasting on urinary stones. Materials and Methods: Very few studies have been carried out on urinary stones and the effect of Ramadan fasting. The sources of the present study are Medline and articles presented by local and Muslim researchers. Meanwhile, since we are acquainted with three well-known researchers in the field of urology, we contacted them via email and asked for their professional opinions. Results: The results of studies about the relationship of urinary stones and their incidence in Ramadan are not alike, and are even sometimes contradictory. Some believe that increased incidence of urinary stones in Ramadan is related not to fasting, but to the rise of weather temperature in hot months, and an increase in humidity. Conclusion: Numerous biological and behavioral changes occur in people who fast in Ramadan and some researchers believe that urinary stone increases during this month.

  11. Fasting and urinary stones

    Directory of Open Access Journals (Sweden)

    Ali Shamsa

    2013-12-01

    Full Text Available Introduction: Fasting is considered as one of the most important practices of Islam, and according to Prophet Mohammad, fasting is obligatory upon Muslims. The aim of this study is to evaluate the effects of fasting on urinary stones. Materials and Methods:Very few studies have been carried out on urinary stones and the effect of Ramadan fasting. The sources of the present study are Medline and articles presented by local and Muslim researchers. Meanwhile, since we are acquainted with three well-known researchers in the field  of urology, we contacted them via email and asked for their professional opinions. Results:The results of studies about the relationship of urinary stones and their incidence in Ramadan are not alike, and are even sometimes contradictory. Some believe that increased incidence of urinary stones in Ramadan is related not to fasting, but to the rise of weather temperature in hot months, and an increase in humidity. Conclusion: Numerous biological and behavioral changes occur in people who fast in Ramadan and some researchers believe that urinary stone increases during this month.

  12. CALCULATION OF TRANSFORMATION DRIVING FORCE FOR THE PRECIPITATION OF NANO-SCALED CEMENTITES IN THE HYPOEUTECTOID STEELS THROUGH ULTRA FAST COOLING%超快速冷却条件下亚共析钢中纳米级渗碳体析出的相变驱动力计算

    Institute of Scientific and Technical Information of China (English)

    王斌; 刘振宇; 周晓光; 王国栋

    2013-01-01

    根据KRC和LFG模型提出的Fe-C合金的奥氏体相变机制,系统地计算了过冷奥氏体的相变驱动力,从热力学的角度分析了过冷奥氏体分解生成纳米级渗碳体颗粒的可能性,并且在热轧后超快速冷却的条件下,发现热轧亚共析钢的组织中存在大量纳米级渗碳体弥散分布的区域,渗碳体的尺寸在十到几十纳米,实现了在无微合金元素添加的条件下渗碳体的纳米级析出.此外,在过冷奥氏体组织中先共析铁素体附近存在大量的富C区,根据平衡浓度计算,局部C的摩尔分数可达到0.04-0.08,这部分高浓度的奥氏体分解析出纳米级渗碳体的倾向性更大.%In order to meet both the development requirements for reduction in cost and strengthening, recently, the research of precipitation of cementites, as the most economical and common precipitates in steels, has drawn wide attention in the field of precipitation strengthening again, because if cementites could be effectively refined to the scale of a few nanometers, it could also generate very strong precipitation strengthening effects to replace the strengthening role of the precipitates of micro-alloying elements. However, the cementites in hypoeutectoid steels usually form lamellar pearlite structure in near-equilibrium conditions, unable to form the precipitation of nanoscale particles, and they tend to be coarsened significantly at high temperatures after hot rolling. Therefore, the non-equilibrium precipitation of cementites only could be realized by increasing cooling rate after hot rolling, and the thermodynamic feasibility for the formation of nanoscale cementite precipitates during cooling has to be determined. In this work, according to the austenitic transformation mechanism of KRC and LFG models in Fe-C alloys, the transformation driving force of undercooled austen-ite was calculated systematically in a thermodynamic view, and the effect of ultra fast cooling (UFC) after hot

  13. Pressure vessel calculations for VVER-440 reactors.

    Science.gov (United States)

    Hordósy, G; Hegyi, Gy; Keresztúri, A; Maráczy, Cs; Temesvári, E; Vértes, P; Zsolnay, E

    2005-01-01

    For the determination of the fast neutron load of the reactor pressure vessel a mixed calculational procedure was developed. The procedure was applied to the Unit II of Paks NPP, Hungary. The neutron source on the outer surfaces of the reactor was determined by a core design code, and the neutron transport calculations outside the core were performed by the Monte Carlo code MCNP. The reaction rate in the activation detectors at surveillance positions and at the cavity were calculated and compared with measurements. In most cases, fairly good agreement was found.

  14. Magnetic Field Calculator

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Magnetic Field Calculator will calculate the total magnetic field, including components (declination, inclination, horizontal intensity, northerly intensity,...

  15. A fast friend

    Institute of Scientific and Technical Information of China (English)

    高怡

    2010-01-01

    我们都知道fast food的意思是“快餐”。那fast friend能解释为“快速或速成的朋友”吗?也许你会说:“什么是速成朋友呀?It doesn’t make sense.”没错,交朋友怎么会有速成的呢?原来;fast还有一个意思是“忠实的、牢固的”,所以a fast friend的真正意思是“可靠、忠实的朋友”。

  16. Fast Distributed Gradient Methods

    CERN Document Server

    Jakovetic, Dusan; Moura, Jose M F

    2011-01-01

    The paper proposes new fast distributed optimization gradient methods and proves convergence to the exact solution at rate O(\\log k/k), much faster than existing distributed optimization (sub)gradient methods with convergence O(1/\\sqrt{k}), while incurring practically no additional communication nor computation cost overhead per iteration. We achieve this for convex (with at least one strongly convex,) coercive, three times differentiable and with Lipschitz continuous first derivative (private) cost functions. Our work recovers for distributed optimization similar convergence rate gains obtained by centralized Nesterov gradient and fast iterative shrinkage-thresholding algorithm (FISTA) methods over ordinary centralized gradient methods. We also present a constant step size distributed fast gradient algorithm for composite non-differentiable costs. A simulation illustrates the effectiveness of our distributed methods.

  17. Fast ejendom II

    DEFF Research Database (Denmark)

    Munk-Hansen, Carsten

    Fremstillingen påviser, at lov om forbrugerbeskyttelse ved erhvervelse af fast ejendom mv. lider af en række svagheder og at ankenævnspraksis bevæger sig væk fra retspraksis på en række områder.......Fremstillingen påviser, at lov om forbrugerbeskyttelse ved erhvervelse af fast ejendom mv. lider af en række svagheder og at ankenævnspraksis bevæger sig væk fra retspraksis på en række områder....

  18. Moms og fast ejendom

    DEFF Research Database (Denmark)

    Edlund, Hans Henrik

    1999-01-01

    I artiklen gives et overblik over, hvorledes fast ejendom behandles momsmæssigt. Derfor findes en kort skitsering af reglerne for moms på byggearbejder, afgrænsningen mellem momspligtig og momsfri udlejning, muligheden for frivillig registrering af udlejning samt opgørelse af reguleringsforpligte......I artiklen gives et overblik over, hvorledes fast ejendom behandles momsmæssigt. Derfor findes en kort skitsering af reglerne for moms på byggearbejder, afgrænsningen mellem momspligtig og momsfri udlejning, muligheden for frivillig registrering af udlejning samt opgørelse af...

  19. Fast Josephson vortex

    Energy Technology Data Exchange (ETDEWEB)

    Malishevskii, A.S.; Silin, V.P.; Uryupin, S.A

    2002-12-30

    For the magnetically coupled waveguide and long Josephson junction we gave the analytic description of two separate velocity domains where the free motion of traveling vortex (2{pi}-kink) exists. The role of the mutual influence of waveguide and long Josephson junction is discussed. It is shown the possibility of the fast vortex motion with the velocity much larger than Swihart velocity of Josephson junction and close to the speed of light in the waveguide. The excitation of motion of such fast Josephson vortex is described.

  20. ATLAS fast physics monitoring

    Indian Academy of Sciences (India)

    Karsten Köneke; on behalf of the ATLAS Collaboration

    2012-11-01

    The ATLAS experiment at the Large Hadron Collider is recording data from proton–proton collisions at a centre-of-mass energy of 7 TeV since the spring of 2010. The integrated luminosity has grown nearly exponentially since then and continues to rise fast. The ATLAS Collaboration has set up a framework to automatically process the rapidly growing dataset and produce performance and physics plots for the most interesting analyses. The system is designed to give fast feedback. The histograms are produced within hours of data reconstruction (2–3 days after data taking). Hints of potentially interesting physics signals obtained this way are followed up by physics groups.

  1. Fast foods perception among adolescents by gender and weight status.

    Science.gov (United States)

    Allehdan, Sabika S; Tayyem, Reema F; Bawadi, Hiba A; Al-Awwad, Narmeen J; Al-Mannai, Mariam; Musaiger, Abdulrahman O

    2017-03-01

    Fast food restaurants have become widespread in both developed and developing countries due to nutritional and economic transitions. The frequency of fast food intake is relatively high among adolescents; however, fast food consumption is positively associated with total energy intake and obesity in adolescents. This study aimed to examine the perception of Jordanian adolescents towards fast foods relative to gender and obesity. A cross-sectional survey was conducted on 400 boys and 395 girls, aged 15-18 years. The adolescents completed a validated questionnaire to measure the perception of adolescents towards fast foods during the year 2013-2014. Weight and height were measured. Numbers who were non-overweight, overweight, and obese were calculated for each age and sex using the International Obesity Task Force (IOTF) standard. The majority of participants perceived foods which are eaten as sandwiches as fast foods. A significant difference between boy and girl adolescents was reported regarding perception of French fries ( p fast foods. Girls were significantly more enthusiastic than boys to consider cuscusi plate ( p foods ( p foods ( p foods ( p foods ( p fast foods. The difference between obese and non-obese regarding the perception of fast foods was only significant among boy participants. Western or non-Arab foods, food prepared fast and eaten fast in self-service outlets, and food rich in calories were significantly perceived as fast food by Jordanian adolescents ( p perception of foods as fast foods or non-fast foods was significantly different between both genders as well as in obese and non-obese male Jordanian adolescents.

  2. When fast atom diffraction turns 3D

    Energy Technology Data Exchange (ETDEWEB)

    Zugarramurdi, Asier; Borisov, Andrei G., E-mail: andrei.borissov@u-psud.fr

    2013-12-15

    Fast atom diffraction at surfaces (FAD) in grazing incidence geometry is characterized by the slow motion in the direction perpendicular to the surface and fast motion parallel to the surface plane along a low index direction. It is established experimentally that for the typical surfaces the FAD reveals the 2D diffraction patterns associated with exchange of the reciprocal lattice vector perpendicular to the direction of fast motion. The reciprocal lattice vector exchange along the direction of fast motion is negligible. The usual approximation made in the description of the experimental data is then to assume that the effective potential leading to the diffraction results from the averaging of the 3D surface potential along the atomic strings forming the axial channel. In this work we use full quantum wave packet propagation calculations to study theoretically the possibility to observe the 3D diffraction in FAD experiments. We show that for the surfaces with large unit cell, such as can be the case for reconstructed or vicinal surfaces, the 3D diffraction can be observed. The reciprocal lattice vector exchange along the direction of fast motion leads to several Laue circles in the diffraction pattern.

  3. Handel med fast ejendom

    DEFF Research Database (Denmark)

    Edlund, Hans Henrik

    Bogen tilstræber at give et overblik over nogle af de vigtigste generelle problemområder på markedet for ejendomshandel, der jo bliver mere og mere kompliceret. Værket er opdelt i følgende hovedafsnit: Ejendomsbegrebet. Indgåelse af aftale om salg af fast ejendom. Begrænsninger i adgangen til...

  4. Not so fast

    DEFF Research Database (Denmark)

    Marras, Stefano; Noda, Takuji; Steffensen, John Fleng

    2015-01-01

    , it is an open question whether such supposedly very fast swimmers do use high-speed bursts when feeding on evasive prey, in addition to using their bill for slashing prey. Here, we measured the swimming behavior of sailfish by using high-frequency accelerometry and high-speed video observations during predator...

  5. Fast Passenger Tracks Network

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    China’s fast passenger tracks network consists of four parts:express rail- way with speeds between 300km/h and 350 kin/h,passenger rail lines with speeds between 200 km/h and 250 km/h,intercity high-speed railways that run

  6. Integral Fast Reactor concept

    Energy Technology Data Exchange (ETDEWEB)

    Till, C.E.; Chang, Y.I.

    1986-01-01

    The Integral Fast Reactor (IFR) is an innovative LMR concept, being developed at Argonne National Laboratory, that fully exploits the inherent properties of liquid metal cooling and metallic fuel to achieve breakthroughs in economics and inherent safety. This paper describes key features and potential advantages of the IFR concept, technology development status, fuel cycle economics potential, and future development path.

  7. Fast Air Temperature Sensors

    DEFF Research Database (Denmark)

    Hendricks, Elbert

    1998-01-01

    The note documents briefly work done on a newly developed sensor for making fast temperature measurements on the air flow in the intake ports of an SI engine and in the EGR input line. The work reviewed has been carried out in close cooperation with Civ. Ing. Michael Føns, the author (IAU...

  8. Parallel Fast Legendre Transform

    NARCIS (Netherlands)

    Alves de Inda, M.; Bisseling, R.H.; Maslen, D.K.

    2001-01-01

    We discuss a parallel implementation of a fast algorithm for the discrete polynomial Legendre transform We give an introduction to the DriscollHealy algorithm using polynomial arithmetic and present experimental results on the eciency and accuracy of our implementation The algorithms were implemente

  9. Foinaven fast track flowlines

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, L.H.; Mair, J.

    1996-12-31

    The decision by British Petroleum to develop offshore fields west of the Shetlands in water depths exceeding 500 meters within three and a half years of discovery posed a unique submarine pipeline installation challenge. This paper summarizes the salient features of a fast track program to install a diverless subsea pipeline system using rigid reeled pipe technology in an offshore frontier area.

  10. Fast food tips

    Science.gov (United States)

    ... Order smaller servings when you can. Split some fast-food items to reduce calories and fat. Ask for a "doggy bag." You can also leave the extra food on your plate. Your food choices can teach your children how to eat healthy, too. Choosing a variety ...

  11. Fast Fourier Orthogonalization

    NARCIS (Netherlands)

    Ducas, L.; Prest, T.; Abramov, S.A.; Zima, E.V.; Gao, X-S.

    2016-01-01

    The classical fast Fourier transform (FFT) allows to compute in quasi-linear time the product of two polynomials, in the {\\em circular convolution ring} R[x]/(x^d−1) --- a task that naively requires quadratic time. Equivalently, it allows to accelerate matrix-vector products when the matrix is *circ

  12. Tachycardia | Fast Heart Rate

    Science.gov (United States)

    ... SA) node --- the heart's natural pacemaker - sends out electrical signals faster than usual. The heart rate is fast, but the heart beats properly. Causes of sinus tachycardia A rapid heartbeat may be your body's response to common conditions such as: Fever Anxiety ...

  13. A FAST CONVERGENT METHOD OF ITERATED REGULARIZATION

    Institute of Scientific and Technical Information of China (English)

    Huang Xiaowei; Wu Chuansheng; Wu Di

    2009-01-01

    This article presents a fast convergent method of iterated regularization based on the idea of Landweber iterated regularization, and a method for a-posteriori choice by the Morozov discrepancy principle and the optimum asymptotic convergence order of the regularized solution is obtained. Numerical test shows that the method of iterated regu-larization can quicken the convergence speed and reduce the calculation burden efficiently.

  14. Parametric X-rays at FAST

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Tanaji [Fermilab

    2016-06-01

    We discuss the generation of parametric X-rays (PXR) in the photoinjector at the new FAST facility at Fermilab. Detailed calculations of the intensity spectrum, energy and angular widths and spectral brilliance with a diamond crystal are presented. We also report on expected results with PXR generated while the beam is channeling. The low emittance electron beam makes this facility a promising source for creating brilliant X-rays.

  15. A fast algorithm for finding point sources in the Fermi data stream: FermiFAST

    Science.gov (United States)

    Asvathaman, Asha; Omand, Conor; Barton, Alistair; Heyl, Jeremy S.

    2017-04-01

    We present a new and efficient algorithm for finding point sources in the photon event data stream from the Fermi Gamma-Ray Space Telescope, FermiFAST. The key advantage of FermiFAST is that it constructs a catalogue of potential sources very fast by arranging the photon data in a hierarchical data structure. Using this structure, FermiFAST rapidly finds the photons that could have originated from a potential gamma-ray source. It calculates a likelihood ratio for the contribution of the potential source using the angular distribution of the photons within the region of interest. It can find within a few minutes the most significant half of the Fermi Third Point Source catalogue (3FGL) with nearly 80 per cent purity from the 4 yr of data used to construct the catalogue. If a higher purity sample is desirable, one can achieve a sample that includes the most significant third of the Fermi 3FGL with only 5 per cent of the sources unassociated with Fermi sources. Outside the Galactic plane, all but eight of the 580 FermiFAST detections are associated with 3FGL sources. And of these eight, six yield significant detections of greater than 5σ when a further binned likelihood analysis is performed. This software allows for rapid exploration of the Fermi data, simulation of the source detection to calculate the selection function of various sources and the errors in the obtained parameters of the sources detected.

  16. Beyond Fast Mapping

    OpenAIRE

    Carey, Susan

    2010-01-01

    Since the seminal 1957 studies of word learning by Roger Brown, most experimental studies of lexical acquisition have concerned fast mapping: the process through which a new lexical entry is established, and through which representations of the linguistic context of a newly heard word interact with representations of its nonlinguistic context to fix an initial partial meaning. Here I focus on the subsequent extended process through which the adult meaning is approximated. Two factors lead to ...

  17. Fast Radio Bursts

    Indian Academy of Sciences (India)

    Akshaya Rane; Duncan Lorimer

    2017-09-01

    We summarize our current state of knowledge of fast radio bursts (FRBs) which were first discovered a decade ago. Following an introduction to radio transients in general, including pulsars and rotating radio transients, we discuss the discovery of FRBs. We then discuss FRB follow-up observations in the context of repeat bursts before moving on to review propagation effects on FRB signals, FRB progenitor models and an outlook on FRBs as potential cosmological tools.

  18. PHENIX Fast TOF

    Energy Technology Data Exchange (ETDEWEB)

    Soha, Aria [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Chiu, Mickey [Brookhaven National Lab. (BNL), Upton, NY (United States); Mannel, Eric [Brookhaven National Lab. (BNL), Upton, NY (United States); Stoll, Sean [Brookhaven National Lab. (BNL), Upton, NY (United States); Lynch, Don [Brookhaven National Lab. (BNL), Upton, NY (United States); Boose, Steve [Brookhaven National Lab. (BNL), Upton, NY (United States); Northacker, Dave [Brookhaven National Lab. (BNL), Upton, NY (United States); Alfred, Marcus [Howard Univ., Washington, DC (United States); Lindesay, James [Howard Univ., Washington, DC (United States); Chujo, Tatsuya [Univ. of Tsukuba (Japan); Inaba, Motoi [Univ. of Tsukuba (Japan); Nonaka, Toshihiro [Univ. of Tsukuba (Japan); Sato, Wataru [Univ. of Tsukuba (Japan); Sakatani, Ikumi [Univ. of Tsukuba (Japan); Hirano, Masahiro [Univ. of Tsukuba (Japan); Choi, Ihnjea [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2014-01-15

    This is a technical scope of work (TSW) between the Fermi National Accelerator Laboratory (Fermilab) and the experimenters of PHENIX Fast TOF group who have committed to participate in beam tests to be carried out during the FY2014 Fermilab Test Beam Facility program. The goals for this test beam experiment are to verify the timing performance of the two types of time-of-flight detector prototypes.

  19. Fast Air Temperature Sensors

    DEFF Research Database (Denmark)

    Hendricks, Elbert

    1998-01-01

    The note documents briefly work done on a newly developed sensor for making fast temperature measurements on the air flow in the intake ports of an SI engine and in the EGR input line. The work reviewed has been carried out in close cooperation with Civ. Ing. Michael Føns, the author (IAU......) and Spencer C. Sorenson (ET). The theory which decribes in detail the overall dynamic chracteristics of the sensor was developed at IAU, DTU....

  20. FAST - FREEDOM ASSEMBLY SEQUENCING TOOL PROTOTYPE

    Science.gov (United States)

    Borden, C. S.

    1994-01-01

    FAST is a project management tool designed to optimize the assembly sequence of Space Station Freedom. An appropriate assembly sequence coordinates engineering, design, utilization, transportation availability, and operations requirements. Since complex designs tend to change frequently, FAST assesses the system level effects of detailed changes and produces output metrics that identify preferred assembly sequences. FAST incorporates Space Shuttle integration, Space Station hardware, on-orbit operations, and programmatic drivers as either precedence relations or numerical data. Hardware sequencing information can either be input directly and evaluated via the "specified" mode of operation or evaluated from the input precedence relations in the "flexible" mode. In the specified mode, FAST takes as its input a list of the cargo elements assigned to each flight. The program determines positions for the cargo elements that maximize the center of gravity (c.g.) margin. These positions are restricted by the geometry of the cargo elements and the location of attachment fittings both in the orbiter and on the cargo elements. FAST calculates every permutation of cargo element location according to its height, trunnion fitting locations, and required intercargo element spacing. Each cargo element is tested in both its normal and reversed orientation (rotated 180 degrees). The best solution is that which maximizes the c.g. margin for each flight. In the flexible mode, FAST begins with the first flight and determines all feasible combinations of cargo elements according to mass, volume, EVA, and precedence relation constraints. The program generates an assembly sequence that meets mass, volume, position, EVA, and precedence constraints while minimizing the total number of Shuttle flights required. Issues associated with ground operations, spacecraft performance, logistics requirements and user requirements will be addressed in future versions of the model. FAST is written in C

  1. ADT fast losses MD

    CERN Document Server

    Priebe, A; Dehning, B; Redaelli, S; Salvachua Ferrando, BM; Sapinski, M; Solfaroli Camillocci, M; Valuch, D

    2013-01-01

    The fast beam losses in the order of 1 ms are expected to be a potential major luminosity limitation for higher beam energies after the LHC long shutdown (LS1). Therefore a Quench Test is planned in the winter 2013 to estimate the quench limit in this timescale and revise the current models. This experiment was devoted to determination the LHC Transverse Damper (ADT) as a system for fast losses induction. A non-standard operation of the ADT was used to develop the beam oscillation instead of suppressing them. The sign flip method had allowed us to create the fast losses within several LHC turns at 450 GeV during the previous test (26th March 2012). Thus, the ADT could be potentially used for the studies of the UFO ("Unidentied Falling Object") impact on the cold magnets. Verification of the system capability and investigations of the disturbed beam properties were the main objectives of this MD. During the experiment, the pilot bunches of proton beam were excited independently in the horizontal and vertical ...

  2. Fast Light Optical Gyroscopes

    Science.gov (United States)

    Smith, David D.

    2015-01-01

    Next-generation space missions are currently constrained by existing spacecraft navigation systems which are not fully autonomous. These systems suffer from accumulated dead-reckoning errors and must therefore rely on periodic corrections provided by supplementary technologies that depend on line-of-sight signals from Earth, satellites, or other celestial bodies for absolute attitude and position determination, which can be spoofed, incorrectly identified, occluded, obscured, attenuated, or insufficiently available. These dead-reckoning errors originate in the ring laser gyros themselves, which constitute inertial measurement units. Increasing the time for standalone spacecraft navigation therefore requires fundamental improvements in gyroscope technologies. One promising solution to enhance gyro sensitivity is to place an anomalous dispersion or fast light material inside the gyro cavity. The fast light essentially provides a positive feedback to the gyro response, resulting in a larger measured beat frequency for a given rotation rate as shown in figure 1. Game Changing Development has been investing in this idea through the Fast Light Optical Gyros (FLOG) project, a collaborative effort which began in FY 2013 between NASA Marshall Space Flight Center (MSFC), the U.S. Army Aviation and Missile Research, Development, and Engineering Center (AMRDEC), and Northwestern University. MSFC and AMRDEC are working on the development of a passive FLOG (PFLOG), while Northwestern is developing an active FLOG (AFLOG). The project has demonstrated new benchmarks in the state of the art for scale factor sensitivity enhancement. Recent results show cavity scale factor enhancements of approx.100 for passive cavities.

  3. Flexible Mental Calculation.

    Science.gov (United States)

    Threlfall, John

    2002-01-01

    Suggests that strategy choice is a misleading characterization of efficient mental calculation and that teaching mental calculation methods as a whole is not conducive to flexibility. Proposes an alternative in which calculation is thought of as an interaction between noticing and knowledge. Presents an associated teaching approach to promote…

  4. Geochemical Calculations Using Spreadsheets.

    Science.gov (United States)

    Dutch, Steven Ian

    1991-01-01

    Spreadsheets are well suited to many geochemical calculations, especially those that are highly repetitive. Some of the kinds of problems that can be conveniently solved with spreadsheets include elemental abundance calculations, equilibrium abundances in nuclear decay chains, and isochron calculations. (Author/PR)

  5. Autistic Savant Calendar Calculators.

    Science.gov (United States)

    Patti, Paul J.

    This study identified 10 savants with developmental disabilities and an exceptional ability to calculate calendar dates. These "calendar calculators" were asked to demonstrate their abilities, and their strategies were analyzed. The study found that the ability to calculate dates into the past or future varied widely among these…

  6. A fast digital image correlation method for deformation measurement

    Science.gov (United States)

    Pan, Bing; Li, Kai

    2011-07-01

    Fast and high-accuracy deformation analysis using digital image correlation (DIC) has been increasingly important and highly demanded in recent years. In literature, the DIC method using the Newton-Rapshon (NR) algorithm has been considered as a gold standard for accurate sub-pixel displacement tracking, as it is insensitive to the relative deformation and rotation of the target subset and thus provides highest sub-pixel registration accuracy and widest applicability. A significant drawback of conventional NR-algorithm-based DIC method, however, is its extremely huge computational expense. In this paper, a fast DIC method is proposed deformation measurement by effectively eliminating the repeating redundant calculations involved in the conventional NR-algorithm-based DIC method. Specifically, a reliability-guided displacement scanning strategy is employed to avoid time-consuming integer-pixel displacement searching for each calculation point, and a pre-computed global interpolation coefficient look-up table is utilized to entirely eliminate repetitive interpolation calculation at sub-pixel locations. With these two approaches, the proposed fast DIC method substantially increases the calculation efficiency of the traditional NR-algorithm-based DIC method. The performance of proposed fast DIC method is carefully tested on real experimental images using various calculation parameters. Results reveal that the computational speed of the present fast DIC is about 120-200 times faster than that of the traditional method, without any loss of its measurement accuracy

  7. Metabolic Effects of Intermittent Fasting.

    Science.gov (United States)

    Patterson, Ruth E; Sears, Dorothy D

    2017-08-21

    The objective of this review is to provide an overview of intermittent fasting regimens, summarize the evidence on the health benefits of intermittent fasting, and discuss physiological mechanisms by which intermittent fasting might lead to improved health outcomes. A MEDLINE search was performed using PubMed and the terms "intermittent fasting," "fasting," "time-restricted feeding," and "food timing." Modified fasting regimens appear to promote weight loss and may improve metabolic health. Several lines of evidence also support the hypothesis that eating patterns that reduce or eliminate nighttime eating and prolong nightly fasting intervals may result in sustained improvements in human health. Intermittent fasting regimens are hypothesized to influence metabolic regulation via effects on (a) circadian biology, (b) the gut microbiome, and (c) modifiable lifestyle behaviors, such as sleep. If proven to be efficacious, these eating regimens offer promising nonpharmacological approaches to improving health at the population level, with multiple public health benefits.

  8. How Do Calculators Calculate Trigonometric Functions?

    Science.gov (United States)

    Underwood, Jeremy M.; Edwards, Bruce H.

    How does your calculator quickly produce values of trigonometric functions? You might be surprised to learn that it does not use series or polynomial approximations, but rather the so-called CORDIC method. This paper will focus on the geometry of the CORDIC method, as originally developed by Volder in 1959. This algorithm is a wonderful…

  9. Neighborhood fast food availability and fast food consumption.

    Science.gov (United States)

    Oexle, Nathalie; Barnes, Timothy L; Blake, Christine E; Bell, Bethany A; Liese, Angela D

    2015-09-01

    Recent nutritional and public health research has focused on how the availability of various types of food in a person's immediate area or neighborhood influences his or her food choices and eating habits. It has been theorized that people living in areas with a wealth of unhealthy fast-food options may show higher levels of fast-food consumption, a factor that often coincides with being overweight or obese. However, measuring food availability in a particular area is difficult to achieve consistently: there may be differences in the strict physical locations of food options as compared to how individuals perceive their personal food availability, and various studies may use either one or both of these measures. The aim of this study was to evaluate the association between weekly fast-food consumption and both a person's perceived availability of fast-food and an objective measure of fast-food presence - Geographic Information Systems (GIS) - within that person's neighborhood. A randomly selected population-based sample of eight counties in South Carolina was used to conduct a cross-sectional telephone survey assessing self-report fast-food consumption and perceived availability of fast food. GIS was used to determine the actual number of fast-food outlets within each participant's neighborhood. Using multinomial logistic regression analyses, we found that neither perceived availability nor GIS-based presence of fast-food was significantly associated with weekly fast-food consumption. Our findings indicate that availability might not be the dominant factor influencing fast-food consumption. We recommend using subjective availability measures and considering individual characteristics that could influence both perceived availability of fast food and its impact on fast-food consumption. If replicated, our findings suggest that interventions aimed at reducing fast-food consumption by limiting neighborhood fast-food availability might not be completely effective.

  10. Serum Lipid Profile: Fasting or Non-fasting?

    OpenAIRE

    Nigam, P. K.

    2010-01-01

    Serum lipid profile has now become almost a routine test. It is usually done in fasting state due to certain limitations in non-fasting serum sample. In the recent past efforts have been made to simplify blood sampling by replacing fasting lipid profile with non-fasting lipid profile. However, fasting specimen is preferred if cardiovascular risk assessment is based on total cholesterol, LDL cholesterol or non-HDL cholesterol. A lot has yet to be done in this area. Till then we have to believe...

  11. Serum Lipid Profile: Fasting or Non-fasting?

    OpenAIRE

    Nigam, P. K.

    2010-01-01

    Serum lipid profile has now become almost a routine test. It is usually done in fasting state due to certain limitations in non-fasting serum sample. In the recent past efforts have been made to simplify blood sampling by replacing fasting lipid profile with non-fasting lipid profile. However, fasting specimen is preferred if cardiovascular risk assessment is based on total cholesterol, LDL cholesterol or non-HDL cholesterol. A lot has yet to be done in this area. Till then we have to believe...

  12. Role of fast ignitor in fast-shock ignition concept

    Directory of Open Access Journals (Sweden)

    S. A. Ghasemi

    2014-03-01

    Full Text Available This paper deals with the role of fast ignitor in fast-shock ignition (FSI concept. The semi-analytical model indicates that the FSI target gain is a function of fast ignitor laser wavelength. If the energy of fast ignitor driver is and the laser wavelength is less than 0.53 micron, then with a fuel mass about 2 mg the FSI has a considerable advantage over pure shock ignition and the figure of merit is better than 1.2. When the wavelength of fast ignitor becomes shorter, the approaches , and for wavelengths shorter than 0.25 micron no additional is advantage is obtained.

  13. Hispanics in Fast Food Jobs.

    Science.gov (United States)

    Charner, Ivan; Fraser, Bryna Shore

    A study examined the employment of Hispanics in the fast-food industry. Data were obtained from a national survey of employees at 279 fast-food restaurants from seven companies in which 194 (4.2 percent) of the 4,660 respondents reported being Hispanic. Compared with the total sample, Hispanic fast-food employees were slightly less likely to be…

  14. Measurement of fast neutrons and secondary gamma rays in graphite

    Energy Technology Data Exchange (ETDEWEB)

    Makarious, A.S.; El-Asyd Abdo, A.; Kansouh, W.A. [Atomic Energy Authority, Cairo (Egypt). Nuclear Research Centre; Bashter, I.I. [Zagazig Univ. (Egypt). Faculty of Science

    1996-05-01

    The spatial fluxes and energy distributions of fast neutrons, total gamma rays and secondary gamma rays transmitted through different thicknesses of graphite have been measured. The graphite samples were arranged in front of one of the horizontal channels of the ET-RR-1 reactor. Gamma ray measurements were carried out for bare, cadmium filtered and boron carbide filtered reactor beams. A fast neutron and gamma ray spectrometer with a stilbene crystal was used to measure the spectrum of fast neutrons and gamma rays. Pulse shape discrimination using the zero cross over technique was used to distinguish the proton pulses from the electron pulses. The total fast neutrons macroscopic cross section and the linear attenuation coefficient for gamma rays were derived both for the whole energy range and at different energies. The obtained values were used to calculate the relaxation lengths for fast neutrons and gamma rays. (Author).

  15. Methods for Melting Temperature Calculation

    Science.gov (United States)

    Hong, Qi-Jun

    Melting temperature calculation has important applications in the theoretical study of phase diagrams and computational materials screenings. In this thesis, we present two new methods, i.e., the improved Widom's particle insertion method and the small-cell coexistence method, which we developed in order to capture melting temperatures both accurately and quickly. We propose a scheme that drastically improves the efficiency of Widom's particle insertion method by efficiently sampling cavities while calculating the integrals providing the chemical potentials of a physical system. This idea enables us to calculate chemical potentials of liquids directly from first-principles without the help of any reference system, which is necessary in the commonly used thermodynamic integration method. As an example, we apply our scheme, combined with the density functional formalism, to the calculation of the chemical potential of liquid copper. The calculated chemical potential is further used to locate the melting temperature. The calculated results closely agree with experiments. We propose the small-cell coexistence method based on the statistical analysis of small-size coexistence MD simulations. It eliminates the risk of a metastable superheated solid in the fast-heating method, while also significantly reducing the computer cost relative to the traditional large-scale coexistence method. Using empirical potentials, we validate the method and systematically study the finite-size effect on the calculated melting points. The method converges to the exact result in the limit of a large system size. An accuracy within 100 K in melting temperature is usually achieved when the simulation contains more than 100 atoms. DFT examples of Tantalum, high-pressure Sodium, and ionic material NaCl are shown to demonstrate the accuracy and flexibility of the method in its practical applications. The method serves as a promising approach for large-scale automated material screening in which

  16. Fast ion collective Thomson scattering diagnostic for ITER: Design elements

    DEFF Research Database (Denmark)

    Tsakadze, Erekle; Bindslev, Henrik; Korsholm, Søren Bang

    2008-01-01

    The proposed fast ion collective Thomson scattering (CTS) diagnostic system for ITER provides the unique capability of measuring the temporally and spatially resolved velocity distribution of the confined fast ions and fusion alpha particles in a burning ITER plasma. The present paper describes t...... in the studies, and new HFS receiver mock-up measurements are presented as well as neutron flux calculations of the influence of the increased slot height....

  17. Core calculations of JMTR

    Energy Technology Data Exchange (ETDEWEB)

    Nagao, Yoshiharu [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    1998-03-01

    In material testing reactors like the JMTR (Japan Material Testing Reactor) of 50 MW in Japan Atomic Energy Research Institute, the neutron flux and neutron energy spectra of irradiated samples show complex distributions. It is necessary to assess the neutron flux and neutron energy spectra of an irradiation field by carrying out the nuclear calculation of the core for every operation cycle. In order to advance core calculation, in the JMTR, the application of MCNP to the assessment of core reactivity and neutron flux and spectra has been investigated. In this study, in order to reduce the time for calculation and variance, the comparison of the results of the calculations by the use of K code and fixed source and the use of Weight Window were investigated. As to the calculation method, the modeling of the total JMTR core, the conditions for calculation and the adopted variance reduction technique are explained. The results of calculation are shown. Significant difference was not observed in the results of neutron flux calculations according to the difference of the modeling of fuel region in the calculations by K code and fixed source. The method of assessing the results of neutron flux calculation is described. (K.I.)

  18. Accuracy of helium accumulation fluence monitor for fast reactor dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Chikara; Aoyama, Takafumi [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1998-03-01

    A helium (He) accumulation fluence monitor (HAFM) has been developed for fast reactor dosimetry. In order to evaluate the measurement accuracy of neutron fluence by the HAFM method, the HAFMs of enriched boron (B) and beryllium (Be) were irradiated in the Fast Neutron Source Reactor `YAYOI`. The number of He atoms produced in the HAFMs were measured and compared with the calculated values. As a result of this study, it was confirmed that the neutron fluence could be measured within 5 % by the HAFM method, and that met the required accuracy for fast reactor dosimetry. (author)

  19. FAST NEUTRONIC REACTOR

    Science.gov (United States)

    Snell, A.H.

    1957-12-01

    This patent relates to a reactor and process for carrying out a controlled fast neutron chain reaction. A cubical reactive mass, weighing at least 920 metric tons, of uranium metal containing predominantly U/sup 238/ and having a U/sup 235/ content of at least 7.63% is assembled and the maximum neutron reproduction ratio is limited to not substantially over 1.01 by insertion and removal of a varying amount of boron, the reactive mass being substantially freed of moderator.

  20. Fasting and sport: an introduction.

    Science.gov (United States)

    Maughan, R J

    2010-06-01

    Most humans observe an overnight fast on a daily basis, and the human body copes well with short duration fasting. Periodic fasting is widely practised for cultural, religious or health reasons. Fasting may take many different forms. Prolonged restriction of food and fluid is harmful to health and performance, and it is often automatically assumed that intermittent fasting will lead to decrements in exercise performance. Athletes who choose to fast during training or competitions may therefore be at a disadvantage. The available evidence does not entirely support this view, but there is little or no information on the effects on elite athletes competing in challenging environments. Prolonged periods of training in the fasted state may not allow optimum adaptation of muscles and other tissues. Further research on a wide range of athletes with special nutrition needs is urgently required. In events where performance might be affected, other strategies to eliminate or minimise any effects must be sought.

  1. Calculating correct compilers

    DEFF Research Database (Denmark)

    Bahr, Patrick; Hutton, Graham

    2015-01-01

    In this article, we present a new approach to the problem of calculating compilers. In particular, we develop a simple but general technique that allows us to derive correct compilers from high-level semantics by systematic calculation, with all details of the implementation of the compilers...... falling naturally out of the calculation process. Our approach is based upon the use of standard equational reasoning techniques, and has been applied to calculate compilers for a wide range of language features and their combination, including arithmetic expressions, exceptions, state, various forms...

  2. Radar Signature Calculation Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: The calculation, analysis, and visualization of the spatially extended radar signatures of complex objects such as ships in a sea multipath environment and...

  3. Electrical installation calculations basic

    CERN Document Server

    Kitcher, Christopher

    2013-01-01

    All the essential calculations required for basic electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practice. A step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3Fo

  4. Electrical installation calculations advanced

    CERN Document Server

    Kitcher, Christopher

    2013-01-01

    All the essential calculations required for advanced electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practiceA step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3For apprentices and electrical installatio

  5. Electronics Environmental Benefits Calculator

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Electronics Environmental Benefits Calculator (EEBC) was developed to assist organizations in estimating the environmental benefits of greening their purchase,...

  6. Fast Fourier transform telescope

    Science.gov (United States)

    Tegmark, Max; Zaldarriaga, Matias

    2009-04-01

    We propose an all-digital telescope for 21 cm tomography, which combines key advantages of both single dishes and interferometers. The electric field is digitized by antennas on a rectangular grid, after which a series of fast Fourier transforms recovers simultaneous multifrequency images of up to half the sky. Thanks to Moore’s law, the bandwidth up to which this is feasible has now reached about 1 GHz, and will likely continue doubling every couple of years. The main advantages over a single dish telescope are cost and orders of magnitude larger field-of-view, translating into dramatically better sensitivity for large-area surveys. The key advantages over traditional interferometers are cost (the correlator computational cost for an N-element array scales as Nlog⁡2N rather than N2) and a compact synthesized beam. We argue that 21 cm tomography could be an ideal first application of a very large fast Fourier transform telescope, which would provide both massive sensitivity improvements per dollar and mitigate the off-beam point source foreground problem with its clean beam. Another potentially interesting application is cosmic microwave background polarization.

  7. Fast SCR Thyratron Driver

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, M.N.; /SLAC

    2007-06-18

    As part of an improvement project on the linear accelerator at SLAC, it was necessary to replace the original thyratron trigger generator, which consisted of two chassis, two vacuum tubes, and a small thyratron. All solid-state, fast rise, and high voltage thyratron drivers, therefore, have been developed and built for the 244 klystron modulators. The rack mounted, single chassis driver employs a unique way to control and generate pulses through the use of an asymmetric SCR, a PFN, a fast pulse transformer, and a saturable reactor. The resulting output pulse is 2 kV peak into 50 {Omega} load with pulse duration of 1.5 {mu}s FWHM at 180 Hz. The pulse risetime is less than 40 ns with less than 1 ns jitter. Various techniques are used to protect the SCR from being damaged by high voltage and current transients due to thyratron breakdowns. The end-of-line clipper (EOLC) detection circuit is also integrated into this chassis to interrupt the modulator triggering in the event a high percentage of line reflections occurred.

  8. Fast ions and momentum transport in JET tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Salmi, A.

    2012-07-01

    Fast ions are an inseparable part of fusion plasmas. They can be generated using electromagnetic waves or injected into plasmas as neutrals to heat the bulk plasma and to drive toroidal rotation and current. In future power plants fusion born fast ions deliver the main heating into the plasma. Understanding and controlling the fast ions is of crucial importance for the operation of a power plant. Furthermore, fast ions provide ways to probe the properties of the thermal plasma and get insight of its confinement properties. In this thesis, numerical code packages are used and developed to simulate JET experiments for a range of physics issues related to fast ions. Namely, the clamping fast ion distribution at high energies with RF heating, fast ion ripple torque generation and the toroidal momentum transport properties using NBI modulation technique are investigated. Through a comparison of numerical simulations and the JET experimental data it is shown that the finite Larmor radius effects in ion cyclotron resonance heating are important and that they can prevent fast ion tail formation beyond certain energy. The identified mechanism could be used for tailoring the fast ion distribution in future experiments. Secondly, ASCOT simulations of NBI ions in a ripple field showed that most of the reduction of the toroidal rotation that has been observed in the JET enhanced ripple experiments could be attributed to fast ion ripple torque. Finally, fast ion torque calculations together with momentum transport analysis have led to the conclusion that momentum transport in not purely diffusive but that a convective component, which increases monotonically in radius, exists in a wide range of JET plasmas. Using parameter scans, the convective transport has been shown to be insensitive to collisionality and q-profile but to increase strongly against density gradient. (orig.)

  9. Calculators and Polynomial Evaluation.

    Science.gov (United States)

    Weaver, J. F.

    The intent of this paper is to suggest and illustrate how electronic hand-held calculators, especially non-programmable ones with limited data-storage capacity, can be used to advantage by students in one particular aspect of work with polynomial functions. The basic mathematical background upon which calculator application is built is summarized.…

  10. Fast Food Jobs. National Study of Fast Food Employment.

    Science.gov (United States)

    Charner, Ivan; Fraser, Bryna Shore

    A study examined employment in the fast-food industry. The national survey collected data from employees at 279 fast-food restaurants from seven companies. Female employees outnumbered males by two to one. The ages of those fast-food employees in the survey sample ranged from 14 to 71, with fully 70 percent being in the 16- to 20-year-old age…

  11. Islamic fasting and multiple sclerosis

    Science.gov (United States)

    2014-01-01

    Background Month-long daytime Ramadan fasting pose s major challenges to multiple sclerosis (MS) patients in Muslim countries. Physicians should have practical knowledge on the implications of fasting on MS. We present a summary of database searches (Cochrane Database of Systematic Reviews, PubMed) and a mini-symposium on Ramadan fasting and MS. In this symposium, we aimed to review the effect of fasting on MS and suggest practical guidelines on management. Discussion In general, fasting is possible for most stable patients. Appropriate amendment of drug regimens, careful monitoring of symptoms, as well as providing patients with available evidence on fasting and MS are important parts of management. Evidence from experimental studies suggests that calorie restriction before disease induction reduces inflammation and subsequent demyelination and attenuates disease severity. Fasting does not appear to have unfavorable effects on disease course in patients with mild disability (Expanded Disability Status Scale (EDSS) score ≤3). Most experts believed that during fasting (especially in summer), some MS symptoms (fatigue, fatigue perception, dizziness, spasticity, cognitive problems, weakness, vision, balance, gait) might worsen but return to normal levels during feasting. There was a general consensus that fasting is not safe for patients: on high doses of anti-convulsants, anti-spastics, and corticosteroids; with coagulopathy or active disease; during attacks; with EDSS score ≥7. Summary These data suggest that MS patients should have tailored care. Fasting in MS patients is a challenge that is directly associated with the spiritual belief of the patient. PMID:24655543

  12. Ramadan fasting, pregnancy and lactation

    Directory of Open Access Journals (Sweden)

    Mohsen Khoshniat Nikoo

    2014-04-01

    Full Text Available Background: Fasting and malnutrition during pregnancy is associated with deleterious consequences such as hypoglycemia, ketonemia, impaired fetal IQ, low birth weight and even abortion. Comparison of pregnancy length and year duration shows that about 75% of pregnancies coincided with Ramadan. Also, fasting during Ramadan is not equivalent to hunger and malnutrition, however, knowledge of the effects of Ramadan fasting on pregnancy outcome is important. In this review, the results of all studies related to the possible effects of Ramadan fasting in pregnancy and lactation have been collected. Material and Methods: Keywords such as "Ramadan", "Ramadan Fasting", "Islamic Fasting", "Fasting in Ramadan "and Fasting with words Pregnancy, Birth Weight, Lactation, Preterm, Milk Composition, Breast Milk were searched in PubMed Database, SID (Scientific Information Database, and some regional journals and 40 related articles (descriptive cross - sectional, cohort, clinical trial and review articles from 1968 to 2010 were studied. Results: Based on available information, if the maternal nutrition during Ramadan is good, the normal process of pregnancy will be maintained and Ramadan fasting would not have deleterious effects on fetal physical and mental growth. Conclusion: Considering nutritional tips, nursing mothers could also fast during Ramadan.

  13. Beyond Fast Mapping.

    Science.gov (United States)

    Carey, Susan

    2010-07-08

    Since the seminal 1957 studies of word learning by Roger Brown, most experimental studies of lexical acquisition have concerned fast mapping: the process through which a new lexical entry is established, and through which representations of the linguistic context of a newly heard word interact with representations of its nonlinguistic context to fix an initial partial meaning. Here I focus on the subsequent extended process through which the adult meaning is approximated. Two factors lead to an extended learning process; the size of the hypothesis space and the need, sometimes, for the creation of new semantic primitives. Sometimes lexical learning requires conceptual change. I sketch a learning mechanism through which this can be achieved. A case study of learning the meanings of verbal numerals illustrates the argument.

  14. Materials analysis fast ions

    CERN Document Server

    Denker, A; Rauschenberg, J; Röhrich, J; Strub, E

    2006-01-01

    Materials analysis with ion beams exploits the interaction of ions with the electrons and nuclei in the sample. Among the vast variety of possible analytical techniques available with ion beams we will restrain to ion beam analysis with ion beams in the energy range from one to several MeV per mass unit. It is possible to use either the back-scattered projectiles (RBS – Rutherford Back Scattering) or the recoiled atoms itself (ERDA – Elastic Recoil Detection Analysis) from the elastic scattering processes. These techniques allow the simultaneous and absolute determination of stoichiometry and depth profiles of the detected elements. The interaction of the ions with the electrons in the sample produces holes in the inner electronic shells of the sample atoms, which recombine and emit X-rays characteristic for the element in question. Particle Induced X-ray Emission (PIXE) has shown to be a fast technique for the analysis of elements with an atomic number above 11.

  15. Fast reactor programme in India

    Indian Academy of Sciences (India)

    P Chellapandi; P R Vasudeva Rao; Prabhat Kumar

    2015-09-01

    Role of fast breeder reactor (FBR) in the Indian context has been discussed with appropriate justification. The FBR programme since 1985 till 2030 is highlighted focussing on the current status and future direction of fast breeder test reactor (FBTR), prototype fast breeder reactor (PFBR) and FBR-1 and 2. Design and technological challenges of PFBR and design and safety targets with means to achieve the same are the major highlights of this paper.

  16. Numerical inductance calculations based on first principles.

    Science.gov (United States)

    Shatz, Lisa F; Christensen, Craig W

    2014-01-01

    A method of calculating inductances based on first principles is presented, which has the advantage over the more popular simulators in that fundamental formulas are explicitly used so that a deeper understanding of the inductance calculation is obtained with no need for explicit discretization of the inductor. It also has the advantage over the traditional method of formulas or table lookups in that it can be used for a wider range of configurations. It relies on the use of fast computers with a sophisticated mathematical computing language such as Mathematica to perform the required integration numerically so that the researcher can focus on the physics of the inductance calculation and not on the numerical integration.

  17. Interval arithmetic in calculations

    Science.gov (United States)

    Bairbekova, Gaziza; Mazakov, Talgat; Djomartova, Sholpan; Nugmanova, Salima

    2016-10-01

    Interval arithmetic is the mathematical structure, which for real intervals defines operations analogous to ordinary arithmetic ones. This field of mathematics is also called interval analysis or interval calculations. The given math model is convenient for investigating various applied objects: the quantities, the approximate values of which are known; the quantities obtained during calculations, the values of which are not exact because of rounding errors; random quantities. As a whole, the idea of interval calculations is the use of intervals as basic data objects. In this paper, we considered the definition of interval mathematics, investigated its properties, proved a theorem, and showed the efficiency of the new interval arithmetic. Besides, we briefly reviewed the works devoted to interval analysis and observed basic tendencies of development of integral analysis and interval calculations.

  18. Unit Cost Compendium Calculations

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Unit Cost Compendium (UCC) Calculations raw data set was designed to provide for greater accuracy and consistency in the use of unit costs across the USEPA...

  19. EFFECTIVE DISCHARGE CALCULATION GUIDE

    Institute of Scientific and Technical Information of China (English)

    D.S.BIEDENHARN; C.R.THORNE; P.J.SOAR; R.D.HEY; C.C.WATSON

    2001-01-01

    This paper presents a procedure for calculating the effective discharge for rivers with alluvial channels.An alluvial river adjusts the bankfull shape and dimensions of its channel to the wide range of flows that mobilize the boundary sediments. It has been shown that time-averaged river morphology is adjusted to the flow that, over a prolonged period, transports most sediment. This is termed the effective discharge.The effective discharge may be calculated provided that the necessary data are available or can be synthesized. The procedure for effective discharge calculation presented here is designed to have general applicability, have the capability to be applied consistently, and represent the effects of physical processes responsible for determining the channel, dimensions. An example of the calculations necessary and applications of the effective discharge concept are presented.

  20. Calculativeness and trust

    DEFF Research Database (Denmark)

    Frederiksen, Morten

    2014-01-01

    Williamson’s characterisation of calculativeness as inimical to trust contradicts most sociological trust research. However, a similar argument is found within trust phenomenology. This paper re-investigates Williamson’s argument from the perspective of Løgstrup’s phenomenological theory of trust....... Contrary to Williamson, however, Løgstrup’s contention is that trust, not calculativeness, is the default attitude and only when suspicion is awoken does trust falter. The paper argues that while Williamson’s distinction between calculativeness and trust is supported by phenomenology, the analysis needs...... to take actual subjective experience into consideration. It points out that, first, Løgstrup places trust alongside calculativeness as a different mode of engaging in social interaction, rather conceiving of trust as a state or the outcome of a decision-making process. Secondly, the analysis must take...

  1. Magnetic Field Grid Calculator

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Magnetic Field Properties Calculator will computes the estimated values of Earth's magnetic field(declination, inclination, vertical component, northerly...

  2. Scientific calculating peripheral

    Energy Technology Data Exchange (ETDEWEB)

    Ethridge, C.D.; Nickell, J.D. Jr.; Hanna, W.H.

    1979-09-01

    A scientific calculating peripheral for small intelligent data acquisition and instrumentation systems and for distributed-task processing systems is established with a number-oriented microprocessor controlled by a single component universal peripheral interface microcontroller. A MOS/LSI number-oriented microprocessor provides the scientific calculating capability with Reverse Polish Notation data format. Master processor task definition storage, input data sequencing, computation processing, result reporting, and interface protocol is managed by a single component universal peripheral interface microcontroller.

  3. Current interruption transients calculation

    CERN Document Server

    Peelo, David F

    2014-01-01

    Provides an original, detailed and practical description of current interruption transients, origins, and the circuits involved, and how they can be calculated Current Interruption Transients Calculationis a comprehensive resource for the understanding, calculation and analysis of the transient recovery voltages (TRVs) and related re-ignition or re-striking transients associated with fault current interruption and the switching of inductive and capacitive load currents in circuits. This book provides an original, detailed and practical description of current interruption transients, origins,

  4. Shielding calculations for SSC

    Energy Technology Data Exchange (ETDEWEB)

    Van Ginneken, A.

    1990-03-01

    Monte Carlo calculations of hadron and muon shielding for SSC are reviewed with emphasis on their application to radiation safety and environmental protection. Models and algorithms for simulation of hadronic and electromagnetic showers, and for production and transport of muons in the TeV regime are briefly discussed. Capabilities and limitations of these calculations are described and illustrated with a few examples. 12 refs., 3 figs.

  5. Geometric unsharpness calculations

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, D.J. [International Training and Education Group (INTEG), Oakville, Ontario (Canada)

    2008-07-15

    The majority of radiographers' geometric unsharpness calculations are normally performed with a mathematical formula. However, a majority of codes and standards refer to the use of a nomograph for this calculation. Upon first review, the use of a nomograph appears more complicated but with a few minutes of study and practice it can be just as effective. A review of this article should provide enlightenment. (author)

  6. Source and replica calculations

    Energy Technology Data Exchange (ETDEWEB)

    Whalen, P.P.

    1994-02-01

    The starting point of the Hiroshima-Nagasaki Dose Reevaluation Program is the energy and directional distributions of the prompt neutron and gamma-ray radiation emitted from the exploding bombs. A brief introduction to the neutron source calculations is presented. The development of our current understanding of the source problem is outlined. It is recommended that adjoint calculations be used to modify source spectra to resolve the neutron discrepancy problem.

  7. INVAP's Nuclear Calculation System

    OpenAIRE

    Ignacio Mochi

    2011-01-01

    Since its origins in 1976, INVAP has been on continuous development of the calculation system used for design and optimization of nuclear reactors. The calculation codes have been polished and enhanced with new capabilities as they were needed or useful for the new challenges that the market imposed. The actual state of the code packages enables INVAP to design nuclear installations with complex geometries using a set of easy-to-use input files that minimize user errors due to confusion or mi...

  8. Chinese Experimental Fast Reactor

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    1.1 The Dynamic Parameters of CEFR Zhao Shaozhi Li Zehua Yi Xiaoyi Zhang Yushan The dynamic parameters of CEFR are calculated with the 2DB and PERT-V-E2 code, and the library of 6-group cross section with 1DX code. The parameters cover the reactivity worth for each assembly in the core and reflector, doppler coefficient for dry and wet core, geometry coefficient, isothermal temperature coefficient and power coefficient, etc.

  9. Fast word reading in pure alexia: "fast, yet serial".

    Science.gov (United States)

    Bormann, Tobias; Wolfer, Sascha; Hachmann, Wibke; Neubauer, Claudia; Konieczny, Lars

    2015-01-01

    Pure alexia is a severe impairment of word reading in which individuals process letters serially with a pronounced length effect. Yet, there is considerable variation in the performance of alexic readers with generally very slow, but also occasionally fast responses, an observation addressed rarely in previous reports. It has been suggested that "fast" responses in pure alexia reflect residual parallel letter processing or that they may even be subserved by an independent reading system. Four experiments assessed fast and slow reading in a participant (DN) with pure alexia. Two behavioral experiments investigated frequency, neighborhood, and length effects in forced fast reading. Two further experiments measured eye movements when DN was forced to read quickly, or could respond faster because words were easier to process. Taken together, there was little support for the proposal that "qualitatively different" mechanisms or reading strategies underlie both types of responses in DN. Instead, fast responses are argued to be generated by the same serial-reading strategy.

  10. Fast Theoretical Simulation for Design of Helical Flux Compression Generators

    Institute of Scientific and Technical Information of China (English)

    YANG Xian-Jun; DONG Zhi-Wei

    2006-01-01

    A theoretical scheme is derived to achieve the numerical simulation of helical flux compression generator (HFCG) design, by which not only any physical approximation is not made, but also numerical simulation can be fast obtained. In particular, an analytic formula to calculate the inductance is deduced, which is extremely close to the experimental results. The physical process of relevant interesting physical quantity, such as inductance, enlarging current, and magnetic flux density, can be calculated to compare with the experimentally quantitative results.

  11. Responder fast steering mirror

    Science.gov (United States)

    Bullard, Andrew; Shawki, Islam

    2013-10-01

    Raytheon Space and Airborne Systems (SAS) has designed, built and tested a 3.3-inch diameter fast steering mirror (FSM) for space application. This 2-axis FSM operates over a large angle (over 10 degree range), has a very high servo bandwidth (over 3.3 Khz closed loop bandwidth), has nanoradian-class noise, and is designed to support microradian class line of sight accuracy. The FSM maintains excellent performance over large temperature ranges (which includes wave front error) and has very high reliability with the help of fully redundant angle sensors and actuator circuits. The FSM is capable of achieving all its design requirements while also being reaction-compensated. The reaction compensation is achieved passively and does not need a separate control loop. The FSM has undergone various environmental testing which include exported forces and torques and thermal vacuum testing that support the FSM design claims. This paper presents the mechanical design and test results of the mechanism which satisfies the rigorous vacuum and space application requirements.

  12. Fast dual tomography

    Science.gov (United States)

    Carrion, Philip M.

    1990-09-01

    This paper can be considered as a continuation of the work by Carrion and Carneiro (1989), where a generalized approach to linearized inversion of geophysical data was developed. Their method allows one to incorporate virtually any constraints in the inversion and reformulate the problem in the dual space of Langrangian multipliers (see also Carrion, 1989a). The constrained tomography makes traveltime inversion robust: it automatically rejects “bad data” which correspond to solutions beyond the chosen constraints and allows one to start inversion with an arbitrary chosen initial model.In this paper, I will derive basic formulas for constrained tomographic imaging that can be used in such areas of geophysics as global mapping of the earth interior, exploration geophysics, etc. The method is fast: an example that will be shown in the paper took only 6 min. of VAX CPU time. Had the conventional least-squares matrix inversion been used it would have taken more than 10 hours of the CPU time to solve the same problem.

  13. Fast dual tomography

    Energy Technology Data Exchange (ETDEWEB)

    Carrion, P.M. (PPPG/UFBA - Campus Universitario da Federacao, Salvador-Bahia (Brazil))

    1990-09-01

    This paper can be considered as a continuation of the work by Carrion and Carneiro (1989), where a generalized approach to linearized inversion of geophysical data was developed. Their method allows one to incorporate virtually any constraints in the inversion and reformulate the problem in the dual space of Langrangian multipliers (see also Carrion, 1989a). The constrained tomography makes traveltime inversion robust: it automatically rejects bad data which correspond to solutions beyond the chosen constraints and allows one to start inversion with an arbitrary chosen initial model. In this paper, the author derives basic formulas for constrained tomographic imaging that can be used in such areas of geophysics as global mapping of the earth interior, exploration geophysics, etc. The method is fast: an example that will be shown in the paper took only 6 min. of VAX CPU time. Had the conventional least-squares matrix inversion been used it would have taken more than 10 hours of the CPU time to solve the same problem.

  14. The ATLAS Fast Tracker

    CERN Document Server

    Volpi, Guido; The ATLAS collaboration

    2015-01-01

    The use of tracking information at the trigger level in the LHC Run II period is crucial for the trigger an data acquisition (TDAQ) system. The tracking precision is in fact important to identify specific decay products of the Higgs boson or new phenomena, a well as to distinguish the contributions coming from many contemporary collisions that occur at every bunch crossing. However, the track reconstruction is among the most demanding tasks performed by the TDAQ computing farm; in fact, full reconstruction at full Level-1 trigger accept rate (100 KHz) is not possible. In order to overcome this limitation, the ATLAS experiment is planning the installation of a specific processor: the Fast Tracker (FTK), which is aimed at achieving this goal. The FTK is a pipeline of high performance electronic, based on custom and commercial devices, which is expected to reconstruct, with high resolution, the trajectories of charged tracks with a transverse momentum above 1 GeV, using the ATLAS inner tracker information. Patte...

  15. Fast Flooding over Manhattan

    CERN Document Server

    Clementi, Andrea; Silvestri, Riccardo

    2010-01-01

    We consider a Mobile Ad-hoc NETwork (MANET) formed by n agents that move at speed V according to the Manhattan Random-Way Point model over a square region of side length L. The resulting stationary (agent) spatial probability distribution is far to be uniform: the average density over the "central zone" is asymptotically higher than that over the "suburb". Agents exchange data iff they are at distance at most R within each other. We study the flooding time of this MANET: the number of time steps required to broadcast a message from one source agent to all agents of the network in the stationary phase. We prove the first asymptotical upper bound on the flooding time. This bound holds with high probability, it is a decreasing function of R and V, and it is tight for a wide and relevant range of the network parameters (i.e. L, R and V). A consequence of our result is that flooding over the sparse and highly-disconnected suburb can be as fast as flooding over the dense and connected central zone. Rather surprisin...

  16. Fast Aerial Video Stitching

    Directory of Open Access Journals (Sweden)

    Jing Li

    2014-10-01

    Full Text Available The highly efficient and robust stitching of aerial video captured by unmanned aerial vehicles (UAVs is a challenging problem in the field of robot vision. Existing commercial image stitching systems have seen success with offline stitching tasks, but they cannot guarantee high-speed performance when dealing with online aerial video sequences.In this paper, we present a novel system which has an unique ability to stitch high-frame rate aerial video at a speed of 150 frames per second (FPS. In addition, rather than using a high-speed vision platform such as FPGA or CUDA, our system is running on a normal personal computer. To achieve this, after the careful comparison of the existing invariant features, we choose the FAST corner and binary descriptor for efficient feature extraction and representation, and present a spatial and temporal coherent filter to fuse the UAV motion information into the feature matching. The proposed filter can remove the majority of feature correspondence outliers and significantly increase the speed of robust feature matching by up to 20 times. To achieve a balance between robustness and efficiency, a dynamic key frame-based stitching framework is used to reduce the accumulation errors.Extensive experiments on challenging UAV datasets demonstrate that our approach can break through the speed limitation and generate an accurate stitching image for aerial video stitching tasks.

  17. Fast feedback in classroom practice

    NARCIS (Netherlands)

    Emmett, K.M.; Klaassen, K.; Eijkelhof, H.

    2009-01-01

    In this article we describe one application of the fast feedback method (see Berg 2003 Aust. Sci. Teach. J. 28–34) in secondary mechanics education. Two teachers tried out a particular sequence twice, in consecutive years, once with and once without the use of fast feedback. We found the method to b

  18. Fasting and nonfasting lipid levels

    DEFF Research Database (Denmark)

    Langsted, Anne; Freiberg, Jacob J; Nordestgaard, Børge G

    2008-01-01

    Lipid profiles are usually measured after fasting. We tested the hypotheses that these levels change only minimally in response to normal food intake and that nonfasting levels predict cardiovascular events.......Lipid profiles are usually measured after fasting. We tested the hypotheses that these levels change only minimally in response to normal food intake and that nonfasting levels predict cardiovascular events....

  19. Fasting and nonfasting lipid levels

    DEFF Research Database (Denmark)

    Langsted, Anne; Freiberg, Jacob J; Nordestgaard, Børge G

    2008-01-01

    Lipid profiles are usually measured after fasting. We tested the hypotheses that these levels change only minimally in response to normal food intake and that nonfasting levels predict cardiovascular events.......Lipid profiles are usually measured after fasting. We tested the hypotheses that these levels change only minimally in response to normal food intake and that nonfasting levels predict cardiovascular events....

  20. Glycemic management during Jain fasts

    OpenAIRE

    Sandeep Julka; Alok Sachan; Sarita Bajaj; Rakesh Sahay; Rajeev Chawla; Navneet Agrawal; Banshi Saboo; Unnikrishnan, A. G.; Baruah, Manash P.; Girish Parmar; Sanjay Kalra

    2017-01-01

    This review describes the various fasts observed by adherents of the Jain religion. It attempts to classify them according to their suitability for people with diabetes and suggests appropriate regime and dose modification for those observing these fasts. The review is an endeavor to encourage rational and evidence-based management in this field of diabetology.

  1. Oil Analysis by Fast DSC

    NARCIS (Netherlands)

    Wetten, I.A.; Herwaarden, A.W.; Splinter, R.; Ruth, van S.M.

    2014-01-01

    Thermal analysis of Olive and Sunflower Oil is done by Fast DSC to evaluate its potential to replace DSC for adulteration detection. DSC measurements take hours, Fast DSC minutes. Peak temperatures of the crystallisation peak in cooling for different Olive and Sunflower Oils are both comparable to D

  2. Oil Analysis by Fast DSC

    NARCIS (Netherlands)

    Wetten, I.A.; Herwaarden, A.W.; Splinter, R.; Ruth, van S.M.

    2014-01-01

    Thermal analysis of Olive and Sunflower Oil is done by Fast DSC to evaluate its potential to replace DSC for adulteration detection. DSC measurements take hours, Fast DSC minutes. Peak temperatures of the crystallisation peak in cooling for different Olive and Sunflower Oils are both comparable to

  3. Fast Feedback in Classroom Practice

    Science.gov (United States)

    Emmett, Katrina; Klaassen, Kees; Eijkelhof, Harrie

    2009-01-01

    In this article we describe one application of the fast feedback method (see Berg 2003 "Aust. Sci. Teach. J." 28-34) in secondary mechanics education. Two teachers tried out a particular sequence twice, in consecutive years, once with and once without the use of fast feedback. We found the method to be successful, and the data that we obtained…

  4. Calculations in apheresis.

    Science.gov (United States)

    Neyrinck, Marleen M; Vrielink, Hans

    2015-02-01

    It's important to work smoothly with your apheresis equipment when you are an apheresis nurse. Attention should be paid to your donor/patient and the product you're collecting. It gives additional value to your work when you are able to calculate the efficiency of your procedures. You must be capable to obtain an optimal product without putting your donor/patient at risk. Not only the total blood volume (TBV) of the donor/patient plays an important role, but also specific blood values influence the apheresis procedure. Therefore, not all donors/patients should be addressed in the same way. Calculation of TBV, extracorporeal volume, and total plasma volume is needed. Many issues determine your procedure time. By knowing the collection efficiency (CE) of your apheresis machine, you can calculate the number of blood volumes to be processed to obtain specific results. You can calculate whether you need one procedure to obtain specific results or more. It's not always needed to process 3× the TBV. In this way, it can be avoided that the donor/patient is needless long connected to the apheresis device. By calculating the CE of each device, you can also compare the various devices for quality control reasons, but also nurses/operators.

  5. Direct calculation of current drive efficiency in FISIC code

    Energy Technology Data Exchange (ETDEWEB)

    Wright, J.C.; Phillips, C.K. [Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543-0451 (United States); Bonoli, P.T. [Plasma Fusion Center, MIT Cambridge, Massachusetts 02139 (United States)

    1996-02-01

    Two-dimensional RF modeling codes use a parameterization (1) of current drive efficiencies to calculate fast wave driven currents. This parameterization assumes a uniform quasi-linear diffusion coefficient and requires {ital a} {ital priori} knowledge of the wave polarizations. These difficulties may be avoided by a direct calculation of the quasilinear diffusion coefficient from the Kennel-Englemann form with the field polarizations calculated by the full wave code, FISIC (2). Current profiles are calculated using the adjoint formulation (3). Comparisons between the two formulations are presented. {copyright} {ital 1996 American Institute of Physics.}

  6. Direct calculation of current drive efficiency in FISIC code

    Science.gov (United States)

    Wright, J. C.; Phillips, C. K.; Bonoli, P. T.

    1996-02-01

    Two-dimensional RF modeling codes use a parameterization (1) of current drive efficiencies to calculate fast wave driven currents. This parameterization assumes a uniform quasi-linear diffusion coefficient and requires a priori knowledge of the wave polarizations. These difficulties may be avoided by a direct calculation of the quasilinear diffusion coefficient from the Kennel-Englemann form with the field polarizations calculated by the full wave code, FISIC (2). Current profiles are calculated using the adjoint formulation (3). Comparisons between the two formulations are presented.

  7. OFTIFEL PERSONALIZED NUTRITIONAL CALCULATOR

    Directory of Open Access Journals (Sweden)

    Malte BETHKE

    2016-11-01

    Full Text Available A food calculator for elderly people was elaborated by Centiv GmbH, an active partner in the European FP7 OPTIFEL Project, based on the functional requirement specifications and the existing recommendations for daily allowances across Europe, data which were synthetized and used to give aims in amounts per portion. The OPTIFEL Personalised Nutritional Calculator is the only available online tool which allows to determine on a personalised level the required nutrients for elderly people (65+. It has been developed mainly to support nursing homes providing best possible (personalised nutrient enriched food to their patients. The European FP7 OPTIFEL project “Optimised Food Products for Elderly Populations” aims to develop innovative products based on vegetables and fruits for elderly populations to increase length of independence. The OPTIFEL Personalised Nutritional Calculator is recommended to be used by nursing homes.

  8. Calculating Quenching Weights

    CERN Document Server

    Salgado, C A; Salgado, Carlos A.; Wiedemann, Urs Achim

    2003-01-01

    We calculate the probability (``quenching weight'') that a hard parton radiates an additional energy fraction due to scattering in spatially extended QCD matter. This study is based on an exact treatment of finite in-medium path length, it includes the case of a dynamically expanding medium, and it extends to the angular dependence of the medium-induced gluon radiation pattern. All calculations are done in the multiple soft scattering approximation (Baier-Dokshitzer-Mueller-Peign\\'e-Schiff--Zakharov ``BDMPS-Z''-formalism) and in the single hard scattering approximation (N=1 opacity approximation). By comparison, we establish a simple relation between transport coefficient, Debye screening mass and opacity, for which both approximations lead to comparable results. Together with this paper, a CPU-inexpensive numerical subroutine for calculating quenching weights is provided electronically. To illustrate its applications, we discuss the suppression of hadronic transverse momentum spectra in nucleus-nucleus colli...

  9. Fast computation of Fresnel holograms employing difference

    Science.gov (United States)

    Yoshikawa, Hiroshi; Iwase, Susumu; Oneda, Tadashi

    2000-03-01

    For practical holographic video system, it is important to generated holographic fringe as fast as possible. We have proposed an approximation method that can calculate the Fresnel hologram fast. To compute the hologram, an object is assumed as a collection of self-illuminated points and the fringes from each object point are superposed. To determine the fringe, a distance between object point and sampling point on the hologram is used to obtain phase of the light. Since sampled hologram usually has small pixel intervals, the difference of the distance values between adjacent pixels is also small and its n-th order difference becomes a constant. Therefore, the distance value at certain pixel can be obtained from the neighbor pixel with simple additions. We have investigated approximation errors and computational speed of the method. The numerical results show that the proposed method is quite effective. The distance error can be reduced less that one wavelength with practical parameters and the computational speed becomes 16 times faster than conventional method. With the proposed method, a hologram, which has horizontal parallax only, 1.3 mega- pixels and 1,000 object points, can be calculated less than on second with a personal computer.

  10. Spin Resonance Strength Calculations

    Science.gov (United States)

    Courant, E. D.

    2009-08-01

    In calculating the strengths of depolarizing resonances it may be convenient to reformulate the equations of spin motion in a coordinate system based on the actual trajectory of the particle, as introduced by Kondratenko, rather than the conventional one based on a reference orbit. It is shown that resonance strengths calculated by the conventional and the revised formalisms are identical. Resonances induced by radiofrequency dipoles or solenoids are also treated; with rf dipoles it is essential to consider not only the direct effect of the dipole but also the contribution from oscillations induced by it.

  11. Spin resonance strength calculations

    Energy Technology Data Exchange (ETDEWEB)

    Courant,E.D.

    2008-10-06

    In calculating the strengths of depolarizing resonances it may be convenient to reformulate the equations of spin motion in a coordinate system based on the actual trajectory of the particle, as introduced by Kondratenko, rather than the conventional one based on a reference orbit. It is shown that resonance strengths calculated by the conventional and the revised formalisms are identical. Resonances induced by radiofrequency dipoles or solenoids are also treated; with rf dipoles it is essential to consider not only the direct effect of the dipole but also the contribution from oscillations induced by it.

  12. Parallel solutions of correlation dimension calculation

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The calculation of correlation dimension is a key problem of the fractals. The standard algorithm requires O(N2) computations. The previous improvement methods endeavor to sequentially reduce redundant computation on condition that there are many different dimensional phase spaces, whose application area and performance improvement degree are limited. This paper presents two fast parallel algorithms: O(N2/p + logp) time p processors PRAM algorithm and O(N2/p) time p processors LARPBS algorithm. Analysis and results of numeric computation indicate that the speedup of parallel algorithms relative to sequence algorithms is efficient. Compared with the PRAM algorithm, The LARPBS algorithm is practical, optimally scalable and cost optimal.

  13. Calculation of Ion Equilibrium Temperature in Ultracold Neutral Plasmas

    Institute of Scientific and Technical Information of China (English)

    李金星; 曹明涛; 韩亮; 齐越蓉; 张首刚; 高宏; 李福利; T.C.Killian

    2011-01-01

    We provide a fast iteration method to calculate the ion equilibrium temperature in an ultracold neutral plasma (UNP). The temperature as functions of electron initial temperature and ion density is obtained and compared with the recent UNP experimental data. The theoretical predictions agree with the experimental results very well. The calculated ion equilibrium temperature by this method can be applied to study the UNP expansion process more effectively.%We provide a fast iteration method to calculate the ion equilibrium temperature in an ultracold neutral plasma (UNP).The temperature as functions of electron initial temperature and ion density is obtained and compared with the recent UNP experimental data.The theoretical predictions agree with the experimental results very well.The calculated ion equilibrium temperature by this method can be applied to study the UNP expansion process more effectively.

  14. Fast Neutron Fluence Calculation Benchmark Analysis Based on 3D MC-SN Bidirectional Coupling Method%基于蒙特卡罗-离散纵标双向耦合方法的快中子注量基准分析

    Institute of Scientific and Technical Information of China (English)

    袁龙军; 陈义学; 韩静茹

    2014-01-01

    蒙特卡罗(MC)-离散纵标(SN )双向耦合方法是解决大型复杂核装置屏蔽问题的有效方法。本文针对三维MC-SN 双向耦合方法在大型压水堆核电站屏蔽计算中的应用,进行了基准验证分析。基于美国核管会(NRC)发布的NUREG/CR-6115压水堆基准模型,采用自主开发的三维MC-SN 双向耦合屏蔽计算分析方法,利用MCNP4C精确计算堆芯到热屏蔽精细模型以及位于压力容器内部计算区域的精确模型,三维SN 程序TORT用于进行热屏蔽到第2下降区外表面间的计算。通过自主研发的接口程序实现MC粒子概率分布与SN 角通量密度间的相互转换,实现MC和SN 双向耦合计算。三维MC-SN双向耦合方法计算结果与基准报告提供的MCNP、DORT结果符合良好,初步验证了该方法解决大型复杂核装置屏蔽问题的可行性。%The Monte Carlo (MC)-discrete ordinates (SN ) bidirectional coupling method is an efficient approach to solve shielding calculation of the large complex nuclear facility .The test calculation was taken by the application of the MC-SN bidirectional coupling method on the shielding calculation of the large PWR nuclear facility .Based on the characteristics of NUREG/CR-6115 PWR benchmark model issued by the NRC ,3D Monte Carlo code was employed to accurately simulate the structure from the core to the thermal shield and the dedicated model of the calculation parts locating in the pressure vessel ,while the TORT was used for the calculation from the thermal shield to the second down-comer region .The transform between particle probability distribution of MC and angular flux density of SN was realized by the interface program to achieve the coupling calculation . The calculation results were compared with MCNP and DORT solutions of benchmark report and satisfactory agreements were obtained . The preliminary validity of feasibility by using the method to solve shielding problem of a

  15. Dynamics Calculation of Spoke

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Compared with ellipse cavity, the spoke cavity has many advantages, especially for the low and medium beam energy. It will be used in the superconductor accelerator popular in the future. Based on the spoke cavity, we design and calculate an accelerator

  16. Haida Numbers and Calculation.

    Science.gov (United States)

    Cogo, Robert

    Experienced traders in furs, blankets, and other goods, the Haidas of the 1700's had a well-developed decimal system for counting and calculating. Their units of linear measure included the foot, yard, and fathom, or six feet. This booklet lists the numbers from 1 to 20 in English and Haida; explains the Haida use of ten, hundred, and thousand…

  17. Curvature calculations with GEOCALC

    Energy Technology Data Exchange (ETDEWEB)

    Moussiaux, A.; Tombal, P.

    1987-04-01

    A new method for calculating the curvature tensor has been recently proposed by D. Hestenes. This method is a particular application of geometric calculus, which has been implemented in an algebraic programming language on the form of a package called GEOCALC. They show how to apply this package to the Schwarzchild case and they discuss the different results.

  18. Daylight calculations in practice

    DEFF Research Database (Denmark)

    Iversen, Anne; Roy, Nicolas; Hvass, Mette;

    programs can give different results. This can be due to restrictions in the program itself and/or be due to the skills of the persons setting up the models. This is crucial as daylight calculations are used to document that the demands and recommendations to daylight levels outlined by building authorities...

  19. Fast food: unfriendly and unhealthy.

    Science.gov (United States)

    Stender, S; Dyerberg, J; Astrup, A

    2007-06-01

    Although nutrition experts might be able to navigate the menus of fast-food restaurant chains, and based on the nutritional information, compose apparently 'healthy' meals, there are still many reasons why frequent fast-food consumption at most chains is unhealthy and contributes to weight gain, obesity, type 2 diabetes and coronary artery disease. Fast food generally has a high-energy density, which, together with large portion sizes, induces over consumption of calories. In addition, we have found it to be a myth that the typical fast-food meal is the same worldwide. Chemical analyses of 74 samples of fast-food menus consisting of French fries and fried chicken (nuggets/hot wings) bought in McDonalds and KFC outlets in 35 countries in 2005-2006 showed that the total fat content of the same menu varies from 41 to 65 g at McDonalds and from 42 to 74 g at KFC. In addition, fast food from major chains in most countries still contains unacceptably high levels of industrially produced trans-fatty acids (IP-TFA). IP-TFA have powerful biological effects and may contribute to increased weight gain, abdominal obesity, type 2 diabetes and coronary artery disease. The food quality and portion size need to be improved before it is safe to eat frequently at most fast-food chains.

  20. FastID: Extremely Fast Forensic DNA Comparisons

    Science.gov (United States)

    2017-05-19

    FastID: Extremely Fast Forensic DNA Comparisons Darrell O. Ricke, PhD Bioengineering Systems & Technologies Massachusetts Institute of...Technology Lincoln Laboratory Lexington, MA USA Darrell.Ricke@ll.mit.edu Abstract—Rapid analysis of DNA forensic samples can have a critical impact on...time sensitive investigations. Analysis of forensic DNA samples by massively parallel sequencing is creating the next gold standard for DNA

  1. fast,rapid,quick和speedy

    Institute of Scientific and Technical Information of China (English)

    张德兴

    2003-01-01

    fast,rapid,quick和speedy这组词都有“快的”意思,但将它们放在一起略作议论,仍有必要,并不乏词趣。 fast和rapid虽然有时可以互换使用,彼此仍有差异,fast在作形容词的时候,强调物体进行相对运动。如a fast horse,a fast train.除形容词外,fast可做副词。如:

  2. Molecular imaging with fast beams

    Energy Technology Data Exchange (ETDEWEB)

    Heber, O. [Weizmann Inst. of Science, Rehovoth (Israel). Dept. of Particle Physics; Zajfman, D. [Weizmann Inst. of Science, Rehovoth (Israel). Dept. of Particle Physics; Kella, D. [Weizmann Inst. of Science, Rehovoth (Israel). Dept. of Particle Physics; Vager, Z. [Weizmann Inst. of Science, Rehovoth (Israel). Dept. of Particle Physics; Watson, R.L. [Cyclotron Institute, Texas A and M University, College Station, Texas 77843 (United States); Horvat, V. [Cyclotron Institute, Texas A and M University, College Station, Texas 77843 (United States)

    1995-05-01

    Three dimensional imaging of the molecular dissociation process in fast collisions is presented with two different setups. One setup is for a fast molecular beam from an accelerator colliding with a gas target. The second setup is for a molecular target system and the collision process is with highly ionized fast beam. The advantages of each system are discussed. The three dimensional imaging of the molecular fragments is done with special detectors that combine the CCD image with time of flight data. An example of the molecular beam measurement is given for an 11 MeV B{sub 2} beam. (orig.).

  3. Boosted Fast Flux Loop Alternative Cooling Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Glen R. Longhurst; Donna Post Guillen; James R. Parry; Douglas L. Porter; Bruce W. Wallace

    2007-08-01

    The Gas Test Loop (GTL) Project was instituted to develop the means for conducting fast neutron irradiation tests in a domestic radiation facility. It made use of booster fuel to achieve the high neutron flux, a hafnium thermal neutron absorber to attain the high fast-to-thermal flux ratio, a mixed gas temperature control system for maintaining experiment temperatures, and a compressed gas cooling system to remove heat from the experiment capsules and the hafnium thermal neutron absorber. This GTL system was determined to provide a fast (E > 0.1 MeV) flux greater than 1.0E+15 n/cm2-s with a fast-to-thermal flux ratio in the vicinity of 40. However, the estimated system acquisition cost from earlier studies was deemed to be high. That cost was strongly influenced by the compressed gas cooling system for experiment heat removal. Designers were challenged to find a less expensive way to achieve the required cooling. This report documents the results of the investigation leading to an alternatively cooled configuration, referred to now as the Boosted Fast Flux Loop (BFFL). This configuration relies on a composite material comprised of hafnium aluminide (Al3Hf) in an aluminum matrix to transfer heat from the experiment to pressurized water cooling channels while at the same time providing absorption of thermal neutrons. Investigations into the performance this configuration might achieve showed that it should perform at least as well as its gas-cooled predecessor. Physics calculations indicated that the fast neutron flux averaged over the central 40 cm (16 inches) relative to ATR core mid-plane in irradiation spaces would be about 1.04E+15 n/cm2-s. The fast-to-thermal flux ratio would be in excess of 40. Further, the particular configuration of cooling channels was relatively unimportant compared with the total amount of water in the apparatus in determining performance. Thermal analyses conducted on a candidate configuration showed the design of the water coolant and

  4. Focusing on fast food restaurants alone underestimates the relationship between neighborhood deprivation and exposure to fast food in a large rural area

    Science.gov (United States)

    2011-01-01

    Background Individuals and families are relying more on food prepared outside the home as a source for at-home and away-from-home consumption. Restricting the estimation of fast-food access to fast-food restaurants alone may underestimate potential spatial access to fast food. Methods The study used data from the 2006 Brazos Valley Food Environment Project (BVFEP) and the 2000 U.S. Census Summary File 3 for six rural counties in the Texas Brazos Valley region. BVFEP ground-truthed data included identification and geocoding of all fast-food restaurants, convenience stores, supermarkets, and grocery stores in study area and on-site assessment of the availability and variety of fast-food lunch/dinner entrées and side dishes. Network distance was calculated from the population-weighted centroid of each census block group to all retail locations that marketed fast food (n = 205 fast-food opportunities). Results Spatial access to fast-food opportunities (FFO) was significantly better than to traditional fast-food restaurants (FFR). The median distance to the nearest FFO was 2.7 miles, compared with 4.5 miles to the nearest FFR. Residents of high deprivation neighborhoods had better spatial access to a variety of healthier fast-food entrée and side dish options than residents of low deprivation neighborhoods. Conclusions Our analyses revealed that identifying fast-food restaurants as the sole source of fast-food entrées and side dishes underestimated neighborhood exposure to fast food, in terms of both neighborhood proximity and coverage. Potential interventions must consider all retail opportunities for fast food, and not just traditional FFR. PMID:21266055

  5. Focusing on fast food restaurants alone underestimates the relationship between neighborhood deprivation and exposure to fast food in a large rural area

    Directory of Open Access Journals (Sweden)

    Dean Wesley R

    2011-01-01

    Full Text Available Abstract Background Individuals and families are relying more on food prepared outside the home as a source for at-home and away-from-home consumption. Restricting the estimation of fast-food access to fast-food restaurants alone may underestimate potential spatial access to fast food. Methods The study used data from the 2006 Brazos Valley Food Environment Project (BVFEP and the 2000 U.S. Census Summary File 3 for six rural counties in the Texas Brazos Valley region. BVFEP ground-truthed data included identification and geocoding of all fast-food restaurants, convenience stores, supermarkets, and grocery stores in study area and on-site assessment of the availability and variety of fast-food lunch/dinner entrées and side dishes. Network distance was calculated from the population-weighted centroid of each census block group to all retail locations that marketed fast food (n = 205 fast-food opportunities. Results Spatial access to fast-food opportunities (FFO was significantly better than to traditional fast-food restaurants (FFR. The median distance to the nearest FFO was 2.7 miles, compared with 4.5 miles to the nearest FFR. Residents of high deprivation neighborhoods had better spatial access to a variety of healthier fast-food entrée and side dish options than residents of low deprivation neighborhoods. Conclusions Our analyses revealed that identifying fast-food restaurants as the sole source of fast-food entrées and side dishes underestimated neighborhood exposure to fast food, in terms of both neighborhood proximity and coverage. Potential interventions must consider all retail opportunities for fast food, and not just traditional FFR.

  6. Harmonic calculation software for industrial applications with ASDs

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Asiminoaei, Lucian; Hansen, Steffan

    2007-01-01

    This article describes the evaluation of new harmonic calculation software. By using a combination of a prestored database and new interpolation techniques the software can provide the harmonic data on real applications of a very fast speed. The harmonic results obtained with this software have a...

  7. Fast electron bremsstrahlung in axisymmetric magnetic configuration

    Science.gov (United States)

    Peysson, Y.; Decker, J.

    2008-09-01

    The nonthermal bremsstrahlung is calculated in a plasma with arbitrary axisymmetric magnetic configuration, taking into account the relativistic angular anisotropy of the radiation cross section at high photon energies, the helical winding of the field lines on the magnetic flux surfaces, and the poloidal variation of the electron distribution function including particle trapping effects. The fast electron dynamics during current drive in tokamaks and reverse field pinches can be investigated in detail by coupling this calculation to a bounce-averaged relativistic Fokker-Planck solver, which calculates the electron distribution function. The asymmetry between high- and low-field side hard x-ray emission intensity that has been measured on the Tore-Supra tokamak [Equipe TORE SUPRA, in Proceedings of the 15th Conference on Plasma Physics and Controlled Nuclear Fusion Research, Seville (International Atomic Energy Agency, Vienna, 1995) Vol. 1, IAEA-CN-60/A1-5 (Institute of Physics, Bristol, U.K., 1995), p. 105] is explained for the first time by the role of trapped electrons. A much stronger poloidal asymmetry is predicted for the line-integrated fast electron bremsstrahlung in the poloidal plane of the Madison Symmetric Torus [R. N. Dexter et al., Fusion Tech. 19, 131 (1991)], since the helical winding of the magnetic field lines is much larger for a reverse field pinch configuration. In this case, the hard x-ray emission is no longer a flux surface quantity, which prevents local reconstructions using a standard Abel inversion, whatever the geometrical arrangement of the lines of sight.

  8. Radioprotection calculations for MEGAPIE.

    Science.gov (United States)

    Zanini, L

    2005-01-01

    The MEGAwatt PIlot Experiment (MEGAPIE) liquid lead-bismuth spallation neutron source will commence operation in 2006 at the SINQ facility of the Paul Scherrer Institut. Such an innovative system presents radioprotection concerns peculiar to a liquid spallation target. Several radioprotection issues have been addressed and studied by means of the Monte Carlo transport code, FLUKA. The dose rates in the room above the target, where personnel access may be needed at times, from the activated lead-bismuth and from the volatile species produced were calculated. Results indicate that the dose rate level is of the order of 40 mSv h(-1) 2 h after shutdown, but it can be reduced below the mSv h(-1) level with slight modifications to the shielding. Neutron spectra and dose rates from neutron transport, of interest for possible damage to radiation sensitive components, have also been calculated.

  9. Fast discriminative latent Dirichlet allocation

    Data.gov (United States)

    National Aeronautics and Space Administration — This is the code for fast discriminative latent Dirichlet allocation, which is an algorithm for topic modeling and text classification. The related paper is at...

  10. FastStats: Sinus Conditions

    Science.gov (United States)

    ... please visit this page: About CDC.gov . FastStats Homepage Diseases and Conditions Anemia or Iron Deficiency Arthritis ... Statistics Tables for U.S. Adults: National Health Interview Survey, 2014, Table A-2 [PDF - 219 KB] Physician ...

  11. Fast Picometer Mirror Mount Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation is a 6DOF controllable mirror mount with high dynamic range and fast tip/tilt capability for space based applications. It will enable the...

  12. Fast generation of dendritic cells

    DEFF Research Database (Denmark)

    Kvistborg, P; Bøgh, Marie; Claesson, M H

    2009-01-01

    we have developed fast DC protocol by comparing two different fast DC protocols with SDDC. DC were evaluated by FACS analysis, and the optimal profile was considered: CD14(low), CD80(high), CD83(high), CD86(high), CCR7(high), HLA class I and II(high). FACS profiles were used as the selection criteria...... together with yield and morphology. Two fast DC protocols fulfilled these criteria and were selected for functional analysis. Our results demonstrate that DC generated within 5days or 48h are comparable with SDDC both phenotypically and functionally. However, we found that 48h DC were more susceptible than...... SDDC to the IL-10 inducing stimulus of TLR ligands (R848 and LPS). Thus to determine the clinical relevance of fast DC protocols in cancer settings, small phase I trials should be conducted monitoring regulatory T cells carefully....

  13. Still on the Fast Track

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    North China’s Inner Mongolia Autonomous Region’s development is progressing comparatively fast,though there is still a long way to go until it catches up with advances being made in other parts of China, officials said.

  14. vysmaw: Fast visibility stream muncher

    Science.gov (United States)

    Pokorny, Martin; Law, Casey J.

    2017-10-01

    The vysmaw client library facilitates the development of code for processes to tap into the fast visibility stream on the National Radio Astronomy Observatory's Very Large Array correlator back-end InfiniBand network.

  15. Allegheny County Fast Food Establishments

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The Allegheny County Health Department has generated this list of fast food restaurants by exporting all chain restaurants without an alcohol permit from the...

  16. PIC: Protein Interactions Calculator.

    Science.gov (United States)

    Tina, K G; Bhadra, R; Srinivasan, N

    2007-07-01

    Interactions within a protein structure and interactions between proteins in an assembly are essential considerations in understanding molecular basis of stability and functions of proteins and their complexes. There are several weak and strong interactions that render stability to a protein structure or an assembly. Protein Interactions Calculator (PIC) is a server which, given the coordinate set of 3D structure of a protein or an assembly, computes various interactions such as disulphide bonds, interactions between hydrophobic residues, ionic interactions, hydrogen bonds, aromatic-aromatic interactions, aromatic-sulphur interactions and cation-pi interactions within a protein or between proteins in a complex. Interactions are calculated on the basis of standard, published criteria. The identified interactions between residues can be visualized using a RasMol and Jmol interface. The advantage with PIC server is the easy availability of inter-residue interaction calculations in a single site. It also determines the accessible surface area and residue-depth, which is the distance of a residue from the surface of the protein. User can also recognize specific kind of interactions, such as apolar-apolar residue interactions or ionic interactions, that are formed between buried or exposed residues or near the surface or deep inside.

  17. Self-consistent study on the damping rates of fast moving particles in QGP

    Institute of Scientific and Technical Information of China (English)

    侯德富; 李家荣

    1996-01-01

    A self-consistent calculation method about the damping rates of fast moving particles in QCP is proposed within the real time finite temperature QCD formalism.And the infrared divergence in the naive calculation is overcome without adding by hand a magnetic screening mass as the infrared cutoff.For weak coupling QCD toe damping rates of the fast moving gluon and quark are obtained and their relaxation times in RICH and LHC scales are estimated.

  18. Fast Calorimeter Simulation in ATLAS

    CERN Document Server

    Schaarschmidt, Jana; The ATLAS collaboration

    2017-01-01

    Producing the very large samples of simulated events required by many physics and performance studies with the ATLAS detector using the full GEANT4 detector simulation is highly CPU intensive. Fast simulation tools are a useful way of reducing CPU requirements when detailed detector simulations are not needed. During the LHC Run-1, a fast calorimeter simulation (FastCaloSim) was successfully used in ATLAS. FastCaloSim provides a simulation of the particle energy response at the calorimeter read-out cell level, taking into account the detailed particle shower shapes and the correlations between the energy depositions in the various calorimeter layers. It is interfaced to the standard ATLAS digitization and reconstruction software, and it can be tuned to data more easily than GEANT4. It is 500 times faster than full simulation in the calorimeter system. Now an improved version of FastCaloSim is in development, incorporating the experience with the version used during Run-1. The new FastCaloSim makes use of mach...

  19. Upgrading ATLAS Fast Calorimeter Simulation

    CERN Document Server

    Heath, Matthew Peter; The ATLAS collaboration

    2017-01-01

    Producing the very large samples of simulated events required by many physics and performance studies with the ATLAS detector using the full GEANT4 detector simulation is highly CPU intensive. Fast simulation tools are a useful way of reducing CPU requirements when detailed detector simulations are not needed. During the LHC Run-1, a fast calorimeter simulation (FastCaloSim) was successfully used in ATLAS. FastCaloSim provides a simulation of the particle energy response at the calorimeter read-out cell level, taking into account the detailed particle shower shapes and the correlations between the energy depositions in the various calorimeter layers. It is interfaced to the standard ATLAS digitization and reconstruction software, and it can be tuned to data more easily than Geant4. Now an improved version of FastCaloSim is in development, incorporating the experience with the version used during Run-1. The new FastCaloSim aims to overcome some limitations of the first version by improving the description of s...

  20. Quantifying Cricket Fast Bowling Skill.

    Science.gov (United States)

    Feros, Simon A; Young, Warren B; O'Brien, Brendan J

    2017-09-27

    To evaluate the current evidence regarding the quantification of cricket fast bowling skill. Studies that assessed fast bowling skill (bowling speed and accuracy) were identified from searches in SPORTDiscus (EBSCO) in June 2017. The reference lists of identified papers were also examined for relevant investigations. Sixteen papers matched the inclusion criteria, and discrepancies in assessment procedures were evident. Differences in: test environment, pitch and cricket ball characteristics, the warm-up prior to test, test familiarisation procedures, permitted run-up lengths, bowling spell length, delivery sequence, test instructions, collection of bowling speed data, collection and reportage of bowling accuracy data were apparent throughout the literature. The reliability and sensitivity of fast bowling skill measures has rarely been reported across the literature. Only one study has attempted to assess the construct validity of their skill measures. There are several discrepancies in how fast bowling skill has been assessed and subsequently quantified in the literature to date. This is a problem, as comparisons between studies are often difficult. Therefore, a strong rationale exists for the creation of match-specific standardised fast bowling assessments that offer greater ecological validity while maintaining acceptable reliability and sensitivity of the skill measures. If prospective research can act on the proposed recommendations from this review, then coaches will be able to make more informed decisions surrounding player selection, talent identification, return to skill following injury, and the efficacy of short- and long-term training interventions for fast bowlers.

  1. Factors affecting calculation of L

    Science.gov (United States)

    Ciotola, Mark P.

    2001-08-01

    A detectable extraterrestrial civilization can be modeled as a series of successive regimes over time each of which is detectable for a certain proportion of its lifecycle. This methodology can be utilized to produce an estimate for L. Potential components of L include quantity of fossil fuel reserves, solar energy potential, quantity of regimes over time, lifecycle patterns of regimes, proportion of lifecycle regime is actually detectable, and downtime between regimes. Relationships between these components provide a means of calculating the lifetime of communicative species in a detectable state, L. An example of how these factors interact is provided, utilizing values that are reasonable given known astronomical data for components such as solar energy potential while existing knowledge about the terrestrial case is used as a baseline for other components including fossil fuel reserves, quantity of regimes over time, and lifecycle patterns of regimes, proportion of lifecycle regime is actually detectable, and gaps of time between regimes due to recovery from catastrophic war or resource exhaustion. A range of values is calculated for L when parameters are established for each component so as to determine the lowest and highest values of L. roadmap for SETI research at the SETI Institute for the next few decades. Three different approaches were identified. 1) Continue the radio search: build an affordable array incorporating consumer market technologies, expand the search frequency, and increase the target list to 100,000 stars. This array will also serve as a technology demonstration and enable the international radio astronomy community to realize an array that is a hundred times larger and capable (among other things) of searching a million stars. 2) Begin searches for very fast optical pulses from a million stars. 3) As Moore's Law delivers increased computational capacity, build an omni-directional sky survey array capable of detecting strong, transient

  2. Theory of Fast Electron Transport for Fast Ignition

    CERN Document Server

    Robinson, A P L; Davies, J R; Gremillet, L; Honrubia, J J; Johzaki, T; Kingham, R J; Sherlock, M; Solodov, A A

    2013-01-01

    Fast Ignition Inertial Confinement Fusion is a variant of inertial fusion in which DT fuel is first compressed to high density and then ignited by a relativistic electron beam generated by a fast (< 20 ps) ultra-intense laser pulse, which is usually brought in to the dense plasma via the inclusion of a re-entrant cone. The transport of this beam from the cone apex into the dense fuel is a critical part of this scheme, as it can strongly influence the overall energetics. Here we review progress in the theory and numerical simulation of fast electron transport in the context of Fast Ignition. Important aspects of the basic plasma physics, descriptions of the numerical methods used, a review of ignition-scale simulations, and a survey of schemes for controlling the propagation of fast electrons are included. Considerable progress has taken place in this area, but the development of a robust, high-gain FI `point design' is still an ongoing challenge.

  3. Zero Temperature Hope Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Rozsnyai, B F

    2002-07-26

    The primary purpose of the HOPE code is to calculate opacities over a wide temperature and density range. It can also produce equation of state (EOS) data. Since the experimental data at the high temperature region are scarce, comparisons of predictions with the ample zero temperature data provide a valuable physics check of the code. In this report we show a selected few examples across the periodic table. Below we give a brief general information about the physics of the HOPE code. The HOPE code is an ''average atom'' (AA) Dirac-Slater self-consistent code. The AA label in the case of finite temperature means that the one-electron levels are populated according to the Fermi statistics, at zero temperature it means that the ''aufbau'' principle works, i.e. no a priory electronic configuration is set, although it can be done. As such, it is a one-particle model (any Hartree-Fock model is a one particle model). The code is an ''ion-sphere'' model, meaning that the atom under investigation is neutral within the ion-sphere radius. Furthermore, the boundary conditions for the bound states are also set at the ion-sphere radius, which distinguishes the code from the INFERNO, OPAL and STA codes. Once the self-consistent AA state is obtained, the code proceeds to generate many-electron configurations and proceeds to calculate photoabsorption in the ''detailed configuration accounting'' (DCA) scheme. However, this last feature is meaningless at zero temperature. There is one important feature in the HOPE code which should be noted; any self-consistent model is self-consistent in the space of the occupied orbitals. The unoccupied orbitals, where electrons are lifted via photoexcitation, are unphysical. The rigorous way to deal with that problem is to carry out complete self-consistent calculations both in the initial and final states connecting photoexcitations, an enormous computational task

  4. Linewidth calculations and simulations

    CERN Document Server

    Strandberg, Ingrid

    2016-01-01

    We are currently developing a new technique to further enhance the sensitivity of collinear laser spectroscopy in order to study the most exotic nuclides available at radioactive ion beam facilities, such as ISOLDE at CERN. The overall goal is to evaluate the feasibility of the new method. This report will focus on the determination of the expected linewidth (hence resolution) of this approach. Different effects which could lead to a broadening of the linewidth, e.g. the ions' energy spread and their trajectories inside the trap, are studied with theoretical calculations as well as simulations.

  5. Acute calculous cholecystitis

    OpenAIRE

    Angarita, Fernando A.; University Health Network; Acuña, Sergio A.; Mount Sinai Hospital; Jimenez, Carolina; University of Toronto; Garay, Javier; Pontificia Universidad Javeriana; Gömez, David; University of Toronto; Domínguez, Luis Carlos; Pontificia Universidad Javeriana

    2010-01-01

    Acute calculous cholecystitis is the most important cause of cholecystectomies worldwide. We review the physiopathology of the inflammatory process in this organ secondary to biliary tract obstruction, as well as its clinical manifestations, workup, and the treatment it requires. La colecistitis calculosa aguda es la causa más importante de colecistectomías en el mundo. En esta revisión de tema se resume la fisiopatología del proceso inflamatorio de la vesículabiliar secundaria a la obstru...

  6. Calculations in furnace technology

    CERN Document Server

    Davies, Clive; Hopkins, DW; Owen, WS

    2013-01-01

    Calculations in Furnace Technology presents the theoretical and practical aspects of furnace technology. This book provides information pertinent to the development, application, and efficiency of furnace technology. Organized into eight chapters, this book begins with an overview of the exothermic reactions that occur when carbon, hydrogen, and sulfur are burned to release the energy available in the fuel. This text then evaluates the efficiencies to measure the quantity of fuel used, of flue gases leaving the plant, of air entering, and the heat lost to the surroundings. Other chapters consi

  7. Anomalous Flattening of the Fast-Ion Profile during Alfvén-Eigenmode Activity

    Science.gov (United States)

    Heidbrink, W. W.; Gorelenkov, N. N.; Luo, Y.; van Zeeland, M. A.; White, R. B.; Austin, M. E.; Burrell, K. H.; Kramer, G. J.; Makowski, M. A.; McKee, G. R.; Nazikian, R.

    2007-12-01

    Neutral-beam injection into plasmas with negative central shear produces a rich spectrum of toroidicity-induced and reversed-shear Alfvén eigenmodes in the DIII-D tokamak. The first application of fast-ion Dα (FIDA) spectroscopy to Alfvén-eigenmode physics shows that the central fast-ion profile is anomalously flat in the inner half of the discharge. Neutron and equilibrium measurements corroborate the FIDA data. The current density driven by fast ions is also strongly modified. Calculations based on the measured mode amplitudes do not explain the observed fast-ion transport.

  8. Application of Fast Dynamic Allan Variance for the Characterization of FOGs-Based Measurement While Drilling

    Science.gov (United States)

    Wang, Lu; Zhang, Chunxi; Gao, Shuang; Wang, Tao; Lin, Tie; Li, Xianmu

    2016-01-01

    The stability of a fiber optic gyroscope (FOG) in measurement while drilling (MWD) could vary with time because of changing temperature, high vibration, and sudden power failure. The dynamic Allan variance (DAVAR) is a sliding version of the Allan variance. It is a practical tool that could represent the non-stationary behavior of the gyroscope signal. Since the normal DAVAR takes too long to deal with long time series, a fast DAVAR algorithm has been developed to accelerate the computation speed. However, both the normal DAVAR algorithm and the fast algorithm become invalid for discontinuous time series. What is worse, the FOG-based MWD underground often keeps working for several days; the gyro data collected aboveground is not only very time-consuming, but also sometimes discontinuous in the timeline. In this article, on the basis of the fast algorithm for DAVAR, we make a further advance in the fast algorithm (improved fast DAVAR) to extend the fast DAVAR to discontinuous time series. The improved fast DAVAR and the normal DAVAR are used to responsively characterize two sets of simulation data. The simulation results show that when the length of the time series is short, the improved fast DAVAR saves 78.93% of calculation time. When the length of the time series is long (6×105 samples), the improved fast DAVAR reduces calculation time by 97.09%. Another set of simulation data with missing data is characterized by the improved fast DAVAR. Its simulation results prove that the improved fast DAVAR could successfully deal with discontinuous data. In the end, a vibration experiment with FOGs-based MWD has been implemented to validate the good performance of the improved fast DAVAR. The results of the experience testify that the improved fast DAVAR not only shortens computation time, but could also analyze discontinuous time series. PMID:27941600

  9. Application of Fast Dynamic Allan Variance for the Characterization of FOGs-Based Measurement While Drilling

    Directory of Open Access Journals (Sweden)

    Lu Wang

    2016-12-01

    Full Text Available The stability of a fiber optic gyroscope (FOG in measurement while drilling (MWD could vary with time because of changing temperature, high vibration, and sudden power failure. The dynamic Allan variance (DAVAR is a sliding version of the Allan variance. It is a practical tool that could represent the non-stationary behavior of the gyroscope signal. Since the normal DAVAR takes too long to deal with long time series, a fast DAVAR algorithm has been developed to accelerate the computation speed. However, both the normal DAVAR algorithm and the fast algorithm become invalid for discontinuous time series. What is worse, the FOG-based MWD underground often keeps working for several days; the gyro data collected aboveground is not only very time-consuming, but also sometimes discontinuous in the timeline. In this article, on the basis of the fast algorithm for DAVAR, we make a further advance in the fast algorithm (improved fast DAVAR to extend the fast DAVAR to discontinuous time series. The improved fast DAVAR and the normal DAVAR are used to responsively characterize two sets of simulation data. The simulation results show that when the length of the time series is short, the improved fast DAVAR saves 78.93% of calculation time. When the length of the time series is long ( 6 × 10 5 samples, the improved fast DAVAR reduces calculation time by 97.09%. Another set of simulation data with missing data is characterized by the improved fast DAVAR. Its simulation results prove that the improved fast DAVAR could successfully deal with discontinuous data. In the end, a vibration experiment with FOGs-based MWD has been implemented to validate the good performance of the improved fast DAVAR. The results of the experience testify that the improved fast DAVAR not only shortens computation time, but could also analyze discontinuous time series.

  10. OECD Maximum Residue Limit Calculator

    Science.gov (United States)

    With the goal of harmonizing the calculation of maximum residue limits (MRLs) across the Organisation for Economic Cooperation and Development, the OECD has developed an MRL Calculator. View the calculator.

  11. Calculating Speed of Sound

    Science.gov (United States)

    Bhatnagar, Shalabh

    2017-01-01

    Sound is an emerging source of renewable energy but it has some limitations. The main limitation is, the amount of energy that can be extracted from sound is very less and that is because of the velocity of the sound. The velocity of sound changes as per medium. If we could increase the velocity of the sound in a medium we would be probably able to extract more amount of energy from sound and will be able to transfer it at a higher rate. To increase the velocity of sound we should know the speed of sound. If we go by the theory of classic mechanics speed is the distance travelled by a particle divided by time whereas velocity is the displacement of particle divided by time. The speed of sound in dry air at 20 °C (68 °F) is considered to be 343.2 meters per second and it won't be wrong in saying that 342.2 meters is the velocity of sound not the speed as it's the displacement of the sound not the total distance sound wave covered. Sound travels in the form of mechanical wave, so while calculating the speed of sound the whole path of wave should be considered not just the distance traveled by sound. In this paper I would like to focus on calculating the actual speed of sound wave which can help us to extract more energy and make sound travel with faster velocity.

  12. Multilayer optical calculations

    CERN Document Server

    Byrnes, Steven J

    2016-01-01

    When light hits a multilayer planar stack, it is reflected, refracted, and absorbed in a way that can be derived from the Fresnel equations. The analysis is treated in many textbooks, and implemented in many software programs, but certain aspects of it are difficult to find explicitly and consistently worked out in the literature. Here, we derive the formulas underlying the transfer-matrix method of calculating the optical properties of these stacks, including oblique-angle incidence, absorption-vs-position profiles, and ellipsometry parameters. We discuss and explain some strange consequences of the formulas in the situation where the incident and/or final (semi-infinite) medium are absorptive, such as calculating $T>1$ in the absence of gain. We also discuss some implementation details like complex-plane branch cuts. Finally, we derive modified formulas for including one or more "incoherent" layers, i.e. very thick layers in which interference can be neglected. This document was written in conjunction with ...

  13. A Comparison of Fast Marching, Fast Sweeping and Fast Iterative Methods for the Solution of the Eikonal Equation

    Directory of Open Access Journals (Sweden)

    A. Capozzoli

    2014-11-01

    Full Text Available We compare the computational performance of the Fast Marching Method, the Fast Sweeping Method and the Fast Iterative Method to determine a numerical solution to the eikonal equation. We point out how the Fast Iterative Method outperforms the other two thanks to its parallel processing capabilities.

  14. Preoperative fasting time in children.

    LENUS (Irish Health Repository)

    Adeel, S

    2012-02-01

    The aim of preoperative fasting is to prevent regurgitation and pulmonary aspiration while limiting potential problems of thirst, dehydration and hypoglycaemia. The American Society of Anaesthesiologists (ASA) has suggested guidelines for preoperative fasting for children undergoing elective surgery. We did a postal survey to determine the current practice regarding these guidelines amongst all specialist registrars in anaesthesia in Ireland. A questionnaire was sent to all specialist registrars in anaesthesia (90 in total), 60 (67%) were returned and analysed. The question asked was how long children should be kept fasting before elective surgery. The results of our survey suggest that most of the respondents are following the ASA guidelines for clear fluids and solids however there were differing opinion regarding the duration of fasting for formula milk and breast milk. In conclusion, we would recommend greater awareness and collaboration between anaesthetists, nurses and surgeons to ensure that fasting instructions are consistent with the ASA guidelines and that patient and their parents understand these directives as well.

  15. The LHC Fast Beam Current change Monitor

    CERN Document Server

    Belohrad, D; Jensen, L; Krupa, M; Topaloudis, A

    2013-01-01

    The modularity of the Large Hadron Collider’s (LHC) machine protection system (MPS) allows for the integration of several beam diagnostic instruments. These instruments have not necessarily been designed to have protection functionality, but MPS can still use them to increase the redundancy and reliability of the machine. The LHC fast beam current change monitor (FBCCM) is an example. It is based on analogue signals from fast beam current transformers (FBCT) used nominally to measure the LHC bunch intensities. The FBCCM calculates the magnitude of the beam signal provided by the FBCT, looks for a change over specific time intervals, and triggers a beam dump interlock if losses exceed an energy-dependent threshold. The first prototype of the FBCCM was installed in the LHC during the 2012-2013 run. The aim of this article is to present the FBCCM system and the results obtained, analyse its current performance and provide an outlook for the final system which is expected to be operational after the long LHC sh...

  16. Fast Dump of the ATLAS Toroids

    CERN Document Server

    Dudarev, A; Volpini, Giovanni; Dudarev, Alexey; Kate, Herman Ten

    2010-01-01

    The toroidal magnet system of the ATLAS Detector at CERN consists of a Barrel Toroid (BT) and two End Cap Toroids (ECT-A and ECT-C). Each toroid is built up from eight racetrack coils wound with an aluminum stabilized NbTi conductor and indirectly cooled by forced flow liquid helium. The three toroids operate in series at 20.5 kA with a total stored energy of 1.5 GJ. In order to verify the reliability and effectiveness of the quench protection system, series of fast dump tests have been performed first of the single toroids and finally of the entire toroidal magnet system. In this paper a model to simulate the fast dump of the ATLAS toroids in single mode operation and in full system configuration is presented. The model is validated through comparison with measured data extracted from the ramp-and-quench runs. The calculated energy dissipation in the various coils is in very good agreement (within 1-2\\%) with the enthalpy changes estimated from the temperature measurements of the different parts of the cold ...

  17. MPACT Fast Neutron Multiplicity System Prototype Development

    Energy Technology Data Exchange (ETDEWEB)

    D.L. Chichester; S.A. Pozzi; J.L. Dolan; M.T. Kinlaw; S.J. Thompson; A.C. Kaplan; M. Flaska; A. Enqvist; J.T. Johnson; S.M. Watson

    2013-09-01

    This document serves as both an FY2103 End-of-Year and End-of-Project report on efforts that resulted in the design of a prototype fast neutron multiplicity counter leveraged upon the findings of previous project efforts. The prototype design includes 32 liquid scintillator detectors with cubic volumes 7.62 cm in dimension configured into 4 stacked rings of 8 detectors. Detector signal collection for the system is handled with a pair of Struck Innovative Systeme 16-channel digitizers controlled by in-house developed software with built-in multiplicity analysis algorithms. Initial testing and familiarization of the currently obtained prototype components is underway, however full prototype construction is required for further optimization. Monte Carlo models of the prototype system were performed to estimate die-away and efficiency values. Analysis of these models resulted in the development of a software package capable of determining the effects of nearest-neighbor rejection methods for elimination of detector cross talk. A parameter study was performed using previously developed analytical methods for the estimation of assay mass variance for use as a figure-of-merit for system performance. A software package was developed to automate these calculations and ensure accuracy. The results of the parameter study show that the prototype fast neutron multiplicity counter design is very nearly optimized under the restraints of the parameter space.

  18. Fast Vertical Mining Using Boolean Algebra

    Directory of Open Access Journals (Sweden)

    Hosny M. Ibrahim

    2015-01-01

    Full Text Available The vertical association rules mining algorithm is an efficient mining method, which makes use of support sets of frequent itemsets to calculate the support of candidate itemsets. It overcomes the disadvantage of scanning database many times like Apriori algorithm. In vertical mining, frequent itemsets can be represented as a set of bit vectors in memory, which enables for fast computation. The sizes of bit vectors for itemsets are the main space expense of the algorithm that restricts its expansibility. Therefore, in this paper, a proposed algorithm that compresses the bit vectors of frequent itemsets will be presented. The new bit vector schema presented here depends on Boolean algebra rules to compute the intersection of two compressed bit vectors without making any costly decompression operation. The experimental results show that the proposed algorithm, Vertical Boolean Mining (VBM algorithm is better than both Apriori algorithm and the classical vertical association rule mining algorithm in the mining time and the memory usage.

  19. Secondary ionization and heating by fast electrons

    CERN Document Server

    Furlanetto, Steven

    2009-01-01

    We examine the fate of fast electrons (with energies E>10 eV) in a thermal gas of primordial composition. To follow their interactions with the background gas, we construct a Monte Carlo model that includes: (1) electron-electron scattering (which transforms the electron kinetic energy into heat), (2) collisional ionization of hydrogen and helium (which produces secondary electrons that themselves scatter through the medium), and (3) collisional excitation (which produces secondary photons, whose fates we also follow approximately). For the last process, we explicitly include all transitions to upper levels n<=4, together with a well-motivated extrapolation to higher levels. In all cases, we use recent calculated cross-sections at E<1 keV and the Bethe approximation to extrapolate to higher energies. We compute the fractions of energy deposited as heat, ionization (tracking HI and the helium species separately), and excitation (tracking HI Lyman-alpha separately) under a broad range of conditions approp...

  20. Fast simulation of the NICER instrument

    Science.gov (United States)

    Doty, John P.; Wampler-Doty, Matthew P.; Prigozhin, Gregory Y.; Okajima, Takashi; Arzoumanian, Zaven; Gendreau, Keith

    2016-07-01

    The NICER1 mission uses a complicated physical system to collect information from objects that are, by x-ray timing science standards, rather faint. To get the most out of the data we will need a rigorous understanding of all instrumental effects. We are in the process of constructing a very fast, high fidelity simulator that will help us to assess instrument performance, support simulation-based data reduction, and improve our estimates of measurement error. We will combine and extend existing optics, detector, and electronics simulations. We will employ the Compute Unified Device Architecture (CUDA2) to parallelize these calculations. The price of suitable CUDA-compatible multi-giga op cores is about $0.20/core, so this approach will be very cost-effective.

  1. Fast Computation of Cross-Ambiguity Function

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A novel method based on zoom fast Fourier transform(FFT) is proposed for minimizing the burden processing of cross-ambiguity functions without affecting performance. The low-pass anti-aliasing filter in zoom FFT is realized by using the multistage filtering technique and the weighting processing is employed in the first stage filter to get rid of the redundancy of the computation. In practical systems, the input data is divided into overlapped data frames to avoid loss of detection ability which results in the rapid increase of computational complexity. A segment technique is also proposed in which CAF calculation of overlapped data frames is viewed as slide window FFT to decrease the computational complexity. The experimental results show that compared to the conventional methods, the proposed method can lower computational complexity and is consistent with the real time implementation in existing high-speed digital processors.

  2. Fast beampattern evaluation by polynomial rooting

    Science.gov (United States)

    Häcker, P.; Uhlich, S.; Yang, B.

    2011-07-01

    Current automotive radar systems measure the distance, the relative velocity and the direction of objects in their environment. This information enables the car to support the driver. The direction estimation capabilities of a sensor array depend on its beampattern. To find the array configuration leading to the best angle estimation by a global optimization algorithm, a huge amount of beampatterns have to be calculated to detect their maxima. In this paper, a novel algorithm is proposed to find all maxima of an array's beampattern fast and reliably, leading to accelerated array optimizations. The algorithm works for arrays having the sensors on a uniformly spaced grid. We use a general version of the gcd (greatest common divisor) function in order to write the problem as a polynomial. We differentiate and root the polynomial to get the extrema of the beampattern. In addition, we show a method to reduce the computational burden even more by decreasing the order of the polynomial.

  3. Fast DSP Using FPGAs and DSOs for Machine Diagnostics

    CERN Document Server

    Naylor, G A

    2003-01-01

    Digital signal processing using digital signal processors is now a mature field for machine diagnostics, giving significant benefits, in particular when used to analyze BPM signals for tune measurement and fast feedback systems. We discuss here digital signal processing using Field Programmable Gate arrays (FPGAs) with large gate counts and intelligent oscilloscopes. These offer great potential for the analysis of very fast signals to maximize the information extracted from high bandwidth sensors. FPGAs allow data to be filtered numerically and treated at the speed of data collection of A/D converters in the 100 MHz range. Parallel, fast and continuous treatment of BPM and FCT signals is possible. Examples are given of injection efficiency, turn by turn injection efficiency, turn by turn beam position, amplitude and phase calculation with averaging over each turn or many turns. Modern oscilloscopes include much computational power. In-built DSPs can perform correlations on the traces allowing the applicat...

  4. Molecular Dynamics Calculations

    Science.gov (United States)

    1996-01-01

    The development of thermodynamics and statistical mechanics is very important in the history of physics, and it underlines the difficulty in dealing with systems involving many bodies, even if those bodies are identical. Macroscopic systems of atoms typically contain so many particles that it would be virtually impossible to follow the behavior of all of the particles involved. Therefore, the behavior of a complete system can only be described or predicted in statistical ways. Under a grant to the NASA Lewis Research Center, scientists at the Case Western Reserve University have been examining the use of modern computing techniques that may be able to investigate and find the behavior of complete systems that have a large number of particles by tracking each particle individually. This is the study of molecular dynamics. In contrast to Monte Carlo techniques, which incorporate uncertainty from the outset, molecular dynamics calculations are fully deterministic. Although it is still impossible to track, even on high-speed computers, each particle in a system of a trillion trillion particles, it has been found that such systems can be well simulated by calculating the trajectories of a few thousand particles. Modern computers and efficient computing strategies have been used to calculate the behavior of a few physical systems and are now being employed to study important problems such as supersonic flows in the laboratory and in space. In particular, an animated video (available in mpeg format--4.4 MB) was produced by Dr. M.J. Woo, now a National Research Council fellow at Lewis, and the G-VIS laboratory at Lewis. This video shows the behavior of supersonic shocks produced by pistons in enclosed cylinders by following exactly the behavior of thousands of particles. The major assumptions made were that the particles involved were hard spheres and that all collisions with the walls and with other particles were fully elastic. The animated video was voted one of two

  5. Impact cratering calculations

    Science.gov (United States)

    Ahrens, Thomas J.; Okeefe, J. D.; Smither, C.; Takata, T.

    1991-01-01

    In the course of carrying out finite difference calculations, it was discovered that for large craters, a previously unrecognized type of crater (diameter) growth occurred which was called lip wave propagation. This type of growth is illustrated for an impact of a 1000 km (2a) silicate bolide at 12 km/sec (U) onto a silicate half-space at earth gravity (1 g). The von Misses crustal strength is 2.4 kbar. The motion at the crater lip associated with this wave type phenomena is up, outward, and then down, similar to the particle motion of a surface wave. It is shown that the crater diameter has grown d/a of approximately 25 to d/a of approximately 4 via lip propagation from Ut/a = 5.56 to 17.0 during the time when rebound occurs. A new code is being used to study partitioning of energy and momentum and cratering efficiency with self gravity for finite-sized objects rather than the previously discussed planetary half-space problems. These are important and fundamental subjects which can be addressed with smoothed particle hydrodynamic (SPH) codes. The SPH method was used to model various problems in astrophysics and planetary physics. The initial work demonstrates that the energy budget for normal and oblique impacts are distinctly different than earlier calculations for silicate projectile impact on a silicate half space. Motivated by the first striking radar images of Venus obtained by Magellan, the effect of the atmosphere on impact cratering was studied. In order the further quantify the processes of meteor break-up and trajectory scattering upon break-up, the reentry physics of meteors striking Venus' atmosphere versus that of the Earth were studied.

  6. HI intensity mapping with FAST

    CERN Document Server

    Bigot-Sazy, Marie-Anne; Battye, Richard A; Browne, Ian W A; Chen, Tianyue; Dickinson, Clive; Harper, Stuart; Maffei, Bruno; Olivari, Lucas C; Wilkinson, Peter N

    2015-01-01

    We discuss the detectability of large-scale HI intensity fluctuations using the FAST telescope. We present forecasts for the accuracy of measuring the Baryonic Acoustic Oscillations and constraining the properties of dark energy. The FAST $19$-beam L-band receivers ($1.05$--$1.45$ GHz) can provide constraints on the matter power spectrum and dark energy equation of state parameters ($w_{0},w_{a}$) that are comparable to the BINGO and CHIME experiments. For one year of integration time we find that the optimal survey area is $6000\\,{\\rm deg}^2$. However, observing with larger frequency coverage at higher redshift ($0.95$--$1.35$ GHz) improves the projected errorbars on the HI power spectrum by more than $2~\\sigma$ confidence level. The combined constraints from FAST, CHIME, BINGO and Planck CMB observations can provide reliable, stringent constraints on the dark energy equation of state.

  7. Fast neutron dosimetry. Progress report, July 1, 1979-June 30, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Attix, F.H.

    1980-01-01

    Progress is reported in: the development and testing of new gas mixtures more suitable for fast neutron dosimetry using the common A150-type Tissue-equivalent plastic ion chambers; comparison of photon doses determined with a graphite-walled proportional counter and with paired dosimeters irradiated by 14.8-MeV neutrons; a detector for the direct measurement of LET distributions from irradiation with fast neutrons; LET distributions from fast neutron irradiation of TE-plastic and graphite measured in a cylindrically symmetric geometry; progress in development of a tandem fast neutron and /sup 60/Co gamma ray source irradiation facility; an approach to the correlation of cellular response with lineal energy; calculated and measured HTO atmospheric dispersion rates within meters of a release site; application of cavity theory to fast neutrons; and fast neutron dosimetry by thermally stimulated currents in Al/sub 2/O/sub 3/. (GHT)

  8. Printtimalliston suunnitteluprosessi fast fashion -yritykselle

    OpenAIRE

    Heikkilä, Inna

    2016-01-01

    Opinnäytetyöni käsittelee suunnitteluprosessia fast fashion -yrityksessä. Oman prosessini kautta selvitän, millaisia vaikutuksia fast fashion -ilmiöllä on tekstiilisuunnittelijan työhön ja, mitä suunnittelijalta vaaditaan nopeatempoisessa suunnitteluprosessissa. Opinnäytetyön toimeksiantajana toimii Seppälä. Toiminnallinen osuus koostuu viiden t-paitaprintin suunnittelusta Seppälä Womanin elokuun 2016 mallistoon Seppälän suunnittelijoiden Katja Tuhkasaaren ja Elina Savolaisen ohjauksessa. Teo...

  9. Fast Setting Cement - Literature Survey

    Science.gov (United States)

    1973-01-01

    materials does produce early set times and high strengths . It is re- ported, also, that the addition of 1.5 percent Ca"l 2 to clinkers contain- Ing more than...produce high strength concrete. They include addition of iron asggregate, physical treatment of clinker , ’ addition of highly reactive SiO2 or Ca0, and...Fast-Fix. The Western Co. has developed materials designated as Fast-Fix with rapid setting and high strength properties. Published data show i .1

  10. Fast Food Problems and Responsibilities

    Institute of Scientific and Technical Information of China (English)

    Zhang; Jing

    2015-01-01

    <正>People are living in a world that acquires almost everyone to chase efficiency and speed.The real inner quality of daily life is not approximately taken into people’s consideration.Fast food is one of the common model reactions of this rapid developing society.Recently,it’s getting popular that people would rather have fast food to save time for other extra work.Problems and public concern are following that kind of life condition and someone or something should be put blame on for this.

  11. A GPU implementation of a track-repeating algorithm for proton radiotherapy dose calculations

    CERN Document Server

    Yepes, Pablo P; Taddei, Phillip J

    2010-01-01

    An essential component in proton radiotherapy is the algorithm to calculate the radiation dose to be delivered to the patient. The most common dose algorithms are fast but they are approximate analytical approaches. However their level of accuracy is not always satisfactory, especially for heterogeneous anatomic areas, like the thorax. Monte Carlo techniques provide superior accuracy, however, they often require large computation resources, which render them impractical for routine clinical use. Track-repeating algorithms, for example the Fast Dose Calculator, have shown promise for achieving the accuracy of Monte Carlo simulations for proton radiotherapy dose calculations in a fraction of the computation time. We report on the implementation of the Fast Dose Calculator for proton radiotherapy on a card equipped with graphics processor units (GPU) rather than a central processing unit architecture. This implementation reproduces the full Monte Carlo and CPU-based track-repeating dose calculations within 2%, w...

  12. Fast evaluation of theoretical uncertainties with Sherpa and MCgrid

    CERN Document Server

    Bothmann, Enrico; Schumann, Steffen

    2015-01-01

    The determination of theoretical error estimates and PDF/$\\alpha_S$-fits require fast evaluations of differential cross sections for varied QCD input parameters. These include PDFs, the strong coupling constant $\\alpha_S$ and the renormalisation and factorisation scales. Beyond leading order QCD, a full dedicated calculation for each set of parameters is often too time-consuming, certainly when performing PDF-fits. We report on two methods to overcome this issue for any QCD NLO calculation: The novel event-reweighting feature in Sherpa and the automated generation of interpolation grids using the recently introduced MCgrid interface. For MCgrid we present the newly added support for fastNLO tables and highlight some future developments.

  13. MBPT calculations with ABINIT

    Science.gov (United States)

    Giantomassi, Matteo; Huhs, Georg; Waroquiers, David; Gonze, Xavier

    2014-03-01

    Many-Body Perturbation Theory (MBPT) defines a rigorous framework for the description of excited-state properties based on the Green's function formalism. Within MBPT, one can calculate charged excitations using e.g. Hedin's GW approximation for the electron self-energy. In the same framework, neutral excitations are also well described through the solution of the Bethe-Salpeter equation (BSE). In this talk, we report on the recent developments concerning the parallelization of the MBPT algorithms available in the ABINIT code (www.abinit.org). In particular, we discuss how to improve the parallel efficiency thanks to a hybrid version that employs MPI for the coarse-grained parallelization and OpenMP (a de facto standard for parallel programming on shared memory architectures) for the fine-grained parallelization of the most CPU-intensive parts. Benchmark results obtained with the new implementation are discussed. Finally, we present results for the GW corrections of amorphous SiO2 in the presence of defects and the BSE absorption spectrum. This work has been supported by the Prace project (PaRtnership for Advanced Computing in Europe, http://www.prace-ri.eu).

  14. Fast dynamics perturbation analysis for prediction of protein functional sites

    Directory of Open Access Journals (Sweden)

    Cohn Judith D

    2008-01-01

    Full Text Available Abstract Background We present a fast version of the dynamics perturbation analysis (DPA algorithm to predict functional sites in protein structures. The original DPA algorithm finds regions in proteins where interactions cause a large change in the protein conformational distribution, as measured using the relative entropy Dx. Such regions are associated with functional sites. Results The Fast DPA algorithm, which accelerates DPA calculations, is motivated by an empirical observation that Dx in a normal-modes model is highly correlated with an entropic term that only depends on the eigenvalues of the normal modes. The eigenvalues are accurately estimated using first-order perturbation theory, resulting in a N-fold reduction in the overall computational requirements of the algorithm, where N is the number of residues in the protein. The performance of the original and Fast DPA algorithms was compared using protein structures from a standard small-molecule docking test set. For nominal implementations of each algorithm, top-ranked Fast DPA predictions overlapped the true binding site 94% of the time, compared to 87% of the time for original DPA. In addition, per-protein recall statistics (fraction of binding-site residues that are among predicted residues were slightly better for Fast DPA. On the other hand, per-protein precision statistics (fraction of predicted residues that are among binding-site residues were slightly better using original DPA. Overall, the performance of Fast DPA in predicting ligand-binding-site residues was comparable to that of the original DPA algorithm. Conclusion Compared to the original DPA algorithm, the decreased run time with comparable performance makes Fast DPA well-suited for implementation on a web server and for high-throughput analysis.

  15. Fast data processing with Spark

    CERN Document Server

    Sankar, Krishna

    2015-01-01

    Fast Data Processing with Spark - Second Edition is for software developers who want to learn how to write distributed programs with Spark. It will help developers who have had problems that were too big to be dealt with on a single computer. No previous experience with distributed programming is necessary. This book assumes knowledge of either Java, Scala, or Python.

  16. Fast electromagnetic field strength probes

    NARCIS (Netherlands)

    Leferink, Frank; Serra, Ramiro

    2013-01-01

    Diode detectors and thermocouple detectors are conventionally used to measure electromagnetic field strength. Both detectors have some disadvantages for applications where a fast response and a high dynamic range is required. The diode detector is limited in dynamic range. The dynamic range is impor

  17. Micro mixer with fast diffusion

    NARCIS (Netherlands)

    Miyake, Ryo; Miyake, R.; Lammerink, Theodorus S.J.; Elwenspoek, Michael Curt; Fluitman, J.H.J.

    1993-01-01

    A new concept for micro-mixing of liquid is introduced and feasibility is demonstrated. The mixer allows fast mixing of small amounts of two liquids and it is application to micro-liquid handling systems [1]. The mixer has a channel for the liquid, an inlet port for the reagent, and a 2.2 mm × 2 mm

  18. Fast, Massively Parallel Data Processors

    Science.gov (United States)

    Heaton, Robert A.; Blevins, Donald W.; Davis, ED

    1994-01-01

    Proposed fast, massively parallel data processor contains 8x16 array of processing elements with efficient interconnection scheme and options for flexible local control. Processing elements communicate with each other on "X" interconnection grid with external memory via high-capacity input/output bus. This approach to conditional operation nearly doubles speed of various arithmetic operations.

  19. Fast Timing for Collider Detectors

    CERN Document Server

    CERN. Geneva

    2017-01-01

    Advancements in fast timing particle detectors have opened up new possibilities to design collider detectors that fully reconstruct and separate event vertices and individual particles in the time domain. The applications of these techniques are considered for the physics at HL-LHC.

  20. Physical characterization of the Skua fast burst assembly

    Energy Technology Data Exchange (ETDEWEB)

    Paternoster, R.; Bounds, J.; Sanchez, R.; Miko, D.

    1994-08-01

    In this paper we discuss the system design and ongoing efforts to characterize the machine physics and operating properties of the Skua fast burst assembly. The machine is currently operating up to prompt critical while we await approval for super-prompt burst operations. Efforts have centered on characterizing neutron kinetic properties, comparing calculated and measured temperature coefficients and power distributions, improving the burst reproducibility, examining the site-wide dose characteristics, and fitting the machine with cooling and filtration systems.

  1. A robust and fast generic voltage sag detection technique

    DEFF Research Database (Denmark)

    L. Dantas, Joacillo; Lima, Francisco Kleber A.; Branco, Carlos Gustavo C.;

    2015-01-01

    In this paper, a fast and robust voltage sag detection algorithm, named VPS2D, is introduced. Using the DSOGI, the algorithm creates a virtual positive sequence voltage and monitories the fundamental voltage component of each phase. After calculating the aggregate value in the o:;3-reference frame......, the algorithm can rapidly identify the starting and the ending of symmetric and asymmetric voltage sags, even if there are harmonics on the grid. Simulation and experimental results are given to validate the proposed algorithm....

  2. Fast algorithm for exploring and compressing of large hyperspectral images

    DEFF Research Database (Denmark)

    Kucheryavskiy, Sergey

    2011-01-01

    A new method for calculation of latent variable space for exploratory analysis and dimension reduction of large hyperspectral images is proposed. The method is based on significant downsampling of image pixels with preservation of pixels’ structure in feature (variable) space. To achieve this, in...... can be used first of all for fast compression of large data arrays with principal component analysis or similar projection techniques....

  3. Orbit correction algorithm for SSRF fast orbit feedback system

    Institute of Scientific and Technical Information of China (English)

    LIU Ming; YIN Chongxian; LIU Dekang

    2009-01-01

    A fast orbit feedback system is designed at SSRF to suppress beam orbit disturbance within sub-micron in the bandwidth up to 100 Hz.The SVD (Singular value decomposition) algorithm is applied to calculate the inverse response matrix in global orbit correction.The number of singular eigenvalues will influence orbit noise suppression and corrector strengths.The method to choose singular eigenvalue rejection threshold is studied in this paper,and the simulation and experiment results are also presented.

  4. The rating reliability calculator

    Directory of Open Access Journals (Sweden)

    Solomon David J

    2004-04-01

    Full Text Available Abstract Background Rating scales form an important means of gathering evaluation data. Since important decisions are often based on these evaluations, determining the reliability of rating data can be critical. Most commonly used methods of estimating reliability require a complete set of ratings i.e. every subject being rated must be rated by each judge. Over fifty years ago Ebel described an algorithm for estimating the reliability of ratings based on incomplete data. While his article has been widely cited over the years, software based on the algorithm is not readily available. This paper describes an easy-to-use Web-based utility for estimating the reliability of ratings based on incomplete data using Ebel's algorithm. Methods The program is available public use on our server and the source code is freely available under GNU General Public License. The utility is written in PHP, a common open source imbedded scripting language. The rating data can be entered in a convenient format on the user's personal computer that the program will upload to the server for calculating the reliability and other statistics describing the ratings. Results When the program is run it displays the reliability, number of subject rated, harmonic mean number of judges rating each subject, the mean and standard deviation of the averaged ratings per subject. The program also displays the mean, standard deviation and number of ratings for each subject rated. Additionally the program will estimate the reliability of an average of a number of ratings for each subject via the Spearman-Brown prophecy formula. Conclusion This simple web-based program provides a convenient means of estimating the reliability of rating data without the need to conduct special studies in order to provide complete rating data. I would welcome other researchers revising and enhancing the program.

  5. A new fast algorithm for multitarget tracking in dense clutter

    Institute of Scientific and Technical Information of China (English)

    Weihua QIN; Fei HU; Chaoyin QIN

    2005-01-01

    A fast joint probabilistic data association (FJPDA) algorithm is proposed in this paper. Cluster probability matrix is approximately calculated by a new method, whose elements βli(K) can be taken as evaluation functions. According to values of βti(K), N events with larger joint probabilities can be searched out as the events with guiding joint probabilities, thus, the number of searching nodes will be greatly reduced. As a result, this method effectively reduces the calculation load and makes it possible to be realized on real-time. Theoretical analysis and Monte Carlo simulation results show that this method is efficient.

  6. Scalable fast multipole accelerated vortex methods

    KAUST Repository

    Hu, Qi

    2014-05-01

    The fast multipole method (FMM) is often used to accelerate the calculation of particle interactions in particle-based methods to simulate incompressible flows. To evaluate the most time-consuming kernels - the Biot-Savart equation and stretching term of the vorticity equation, we mathematically reformulated it so that only two Laplace scalar potentials are used instead of six. This automatically ensuring divergence-free far-field computation. Based on this formulation, we developed a new FMM-based vortex method on heterogeneous architectures, which distributed the work between multicore CPUs and GPUs to best utilize the hardware resources and achieve excellent scalability. The algorithm uses new data structures which can dynamically manage inter-node communication and load balance efficiently, with only a small parallel construction overhead. This algorithm can scale to large-sized clusters showing both strong and weak scalability. Careful error and timing trade-off analysis are also performed for the cutoff functions induced by the vortex particle method. Our implementation can perform one time step of the velocity+stretching calculation for one billion particles on 32 nodes in 55.9 seconds, which yields 49.12 Tflop/s.

  7. Fast Chemistry Mechanisms for Climate Applications

    Science.gov (United States)

    Cameron-Smith, P. J.; Connell, P. S.; Bergmann, D. J.; Chuang, C. C.; Prather, M. J.; Lamarque, J.; Hess, P.; Vitt, F.

    2008-12-01

    When atmospheric chemistry is included in long climate and Earth system simulations, the completeness of the chemical mechanism must be balanced with the computational cost, and the scientific interests of the atmospheric chemist must be tempered by the chemical needs of other components of the climate model (e.g, greenhouse gas concentrations for radiative heating, and deposition rates for biosphere interactions). We have implemented two chemical mechanisms for use in long climate simulations. One uses 28 species to calculate ozone, OH, methane, N2O, and sulfate throughout troposphere and stratosphere. The other uses just 15 species to calculate ozone, OH, and sulfate, with the OH providing the means to back-out the lifetime of methane and other species of interest. We have compared the sensitivity of both mechanisms to emission perturbations against the response of a state-of-the-art full chemistry mechanism that uses 90 species. Both fast mechanisms compare well. Prepared by LLNL under Contract DE-AC52-07NA27344.

  8. fast_protein_cluster: parallel and optimized clustering of large-scale protein modeling data.

    Science.gov (United States)

    Hung, Ling-Hong; Samudrala, Ram

    2014-06-15

    fast_protein_cluster is a fast, parallel and memory efficient package used to cluster 60 000 sets of protein models (with up to 550 000 models per set) generated by the Nutritious Rice for the World project. fast_protein_cluster is an optimized and extensible toolkit that supports Root Mean Square Deviation after optimal superposition (RMSD) and Template Modeling score (TM-score) as metrics. RMSD calculations using a laptop CPU are 60× faster than qcprot and 3× faster than current graphics processing unit (GPU) implementations. New GPU code further increases the speed of RMSD and TM-score calculations. fast_protein_cluster provides novel k-means and hierarchical clustering methods that are up to 250× and 2000× faster, respectively, than Clusco, and identify significantly more accurate models than Spicker and Clusco. fast_protein_cluster is written in C++ using OpenMP for multi-threading support. Custom streaming Single Instruction Multiple Data (SIMD) extensions and advanced vector extension intrinsics code accelerate CPU calculations, and OpenCL kernels support AMD and Nvidia GPUs. fast_protein_cluster is available under the M.I.T. license. (http://software.compbio.washington.edu/fast_protein_cluster) © The Author 2014. Published by Oxford University Press.

  9. The Fast-Casual Conundrum: Fast-Casual Restaurant Entrées Are Higher in Calories than Fast Food.

    Science.gov (United States)

    Schoffman, Danielle E; Davidson, Charis R; Hales, Sarah B; Crimarco, Anthony E; Dahl, Alicia A; Turner-McGrievy, Gabrielle M

    2016-10-01

    Frequently eating fast food has been associated with consuming a diet high in calories, and there is a public perception that fast-casual restaurants (eg, Chipotle) are healthier than traditional fast food (eg, McDonald's). However, research has not examined whether fast-food entrées and fast-casual entrées differ in calorie content. The purpose of this study was to determine whether the caloric content of entrées at fast-food restaurants differed from that found at fast-casual restaurants. This study was a cross-sectional analysis of secondary data. Calorie information from 2014 for lunch and dinner entrées for fast-food and fast-casual restaurants was downloaded from the MenuStat database. Mean calories per entrée between fast-food restaurants and fast-casual restaurants and the proportion of restaurant entrées that fell into different calorie ranges were assessed. A t test was conducted to test the hypothesis that there was no difference between the average calories per entrée at fast-food and fast-casual restaurants. To examine the difference in distribution of entrées in different calorie ranges between fast-food and fast-casual restaurants, χ(2) tests were used. There were 34 fast-food and 28 fast-casual restaurants included in the analysis (n=3,193 entrées). Fast-casual entrées had significantly more calories per entrée (760±301 kcal) than fast-food entrées (561±268; Pfast-casual entrées compared with fast-food entrées exceeded the median of 640 kcal per entrée (Pfast-casual entrées contained more calories than fast-food entrées in the study sample, future studies should compare actual purchasing patterns from these restaurants to determine whether the energy content or nutrient density of full meals (ie, entrées with sides and drinks) differs between fast-casual restaurants and fast-food restaurants. Calorie-conscious consumers should consider the calorie content of entrée items before purchase, regardless of restaurant type. Copyright

  10. New Arsenic Cross Section Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Kawano, Toshihiko [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-04

    This report presents calculations for the new arsenic cross section. Cross sections for 73,74,75 As above the resonance range were calculated with a newly developed Hauser-Feshbach code, CoH3.

  11. Cosmological Calculations on the GPU

    CERN Document Server

    Bard, Deborah; Allen, Mark T; Yepremyan, Hasmik; Kratochvil, Jan M

    2012-01-01

    Cosmological measurements require the calculation of nontrivial quantities over large datasets. The next generation of survey telescopes (such as DES, PanSTARRS, and LSST) will yield measurements of billions of galaxies. The scale of these datasets, and the nature of the calculations involved, make cosmological calculations ideal models for implementation on graphics processing units (GPUs). We consider two cosmological calculations, the two-point angular correlation function and the aperture mass statistic, and aim to improve the calculation time by constructing code for calculating them on the GPU. Using CUDA, we implement the two algorithms on the GPU and compare the calculation speeds to comparable code run on the CPU. We obtain a code speed-up of between 10 - 180x faster, compared to performing the same calculation on the CPU. The code has been made publicly available.

  12. The effect of fast-food availability on fast-food consumption and obesity among rural residents: an analysis by race/ethnicity.

    Science.gov (United States)

    Dunn, Richard A; Sharkey, Joseph R; Horel, Scott

    2012-01-01

    Rural areas of the United States tend to have higher obesity rates than urban areas, particularly in regions with high proportions of non-white residents. This paper analyzes the effect of fast-food availability on the level of fast-food consumption and obesity risk among both white and non-white residents of central Texas. Potential endogeneity of fast-food availability is addressed through instrumental variables regression using distance to the nearest major highway as an instrument. We find that non-whites tend to exhibit higher obesity rates, greater access to fast-food establishments and higher consumption of fast-food meals compared to their white counterparts. In addition, we found that whites and non-whites respond differently to the availability of fast-food in rural environments. Greater availability is not associated with either greater consumption of fast-food meals or a higher obesity risk among the sample of whites. In contrast, greater availability of fast-food is positively associated with both the number of meals consumed for non-white rural residents and their obesity. While our results are robust to specification, the effect of availability on weight outcomes is notably weaker when indirectly calculated from the implied relationship between consumption and caloric intake. This highlights the importance of directly examining the proposed mechanism through which an environmental factor influences weight outcomes.

  13. [Preoperative fasting guidelines: an update].

    Science.gov (United States)

    López Muñoz, A C; Busto Aguirreurreta, N; Tomás Braulio, J

    2015-03-01

    Anesthesiology societies have issued various guidelines on preoperative fasting since 1990, not only to decrease the incidence of lung aspiration and anesthetic morbidity, but also to increase patient comfort prior to anesthesia. Some of these societies have been updating their guidelines, as such that, since 2010, we now have 2 evidence-based preoperative fasting guidelines available. In this article, an attempt is made to review these updated guidelines, as well as the current instructions for more controversial patients such as infants, the obese, and a particular type of ophthalmic surgery. Copyright © 2014 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. A Repeating Fast Radio Burst

    CERN Document Server

    Spitler, L G; Hessels, J W T; Bogdanov, S; Brazier, A; Camilo, F; Chatterjee, S; Cordes, J M; Crawford, F; Deneva, J; Ferdman, R D; Freire, P C C; Kaspi, V M; Lazarus, P; Lynch, R; Madsen, E C; McLaughlin, M A; Patel, C; Ransom, S M; Seymour, A; Stairs, I H; Stappers, B W; van Leeuwen, J; Zhu, W W

    2016-01-01

    Fast Radio Bursts are millisecond-duration astronomical radio pulses of unknown physical origin that appear to come from extragalactic distances. Previous follow-up observations have failed to find additional bursts at the same dispersion measures (i.e. integrated column density of free electrons between source and telescope) and sky position as the original detections. The apparent non-repeating nature of the fast radio bursts has led several authors to hypothesise that they originate in cataclysmic astrophysical events. Here we report the detection of ten additional bursts from the direction of FRB121102, using the 305-m Arecibo telescope. These new bursts have dispersion measures and sky positions consistent with the original burst. This unambiguously identifies FRB121102 as repeating and demonstrates that its source survives the energetic events that cause the bursts. Additionally, the bursts from FRB121102 show a wide range of spectral shapes that appear to be predominantly intrinsic to the source and wh...

  15. Spherical Demons: Fast Surface Registration

    Science.gov (United States)

    Yeo, B.T. Thomas; Sabuncu, Mert; Vercauteren, Tom; Ayache, Nicholas; Fischl, Bruce; Golland, Polina

    2009-01-01

    We present the fast Spherical Demons algorithm for registering two spherical images. By exploiting spherical vector spline interpolation theory, we show that a large class of regularizers for the modified demons objective function can be efficiently implemented on the sphere using convolution. Based on the one parameter subgroups of diffeomorphisms, the resulting registration is diffeomorphic and fast – registration of two cortical mesh models with more than 100k nodes takes less than 5 minutes, comparable to the fastest surface registration algorithms. Moreover, the accuracy of our method compares favorably to the popular FreeSurfer registration algorithm. We validate the technique in two different settings: (1) parcellation in a set of in-vivo cortical surfaces and (2) Brodmann area localization in ex-vivo cortical surfaces. PMID:18979813

  16. ATLAS FTK: The Fast Tracker

    CERN Document Server

    T, Iizawa; The ATLAS collaboration

    2014-01-01

    The Fast TracKer (FTK) will perform global track reconstruction after each Level-1 trigger accept to enable the software-based High Level Trigger to have early access to tracking information. FTK is a dedicated processor based on a mixture of advanced technologies. Modern, powerful Field Programmable Gate Arrays (FPGAs) form an important part of the system architecture, and the large level of computing power required for pattern recognition is provided by incorporating standard-cell ASICs named Associative Memory (AM). FTK provides global track reconstruction in the full inner silicon detector in approximately 100 microseconds with resolution comparable to the offline algorithms. It allows a fast and precise detection of the primary and secondary vertex information. The track and vertex information is then used by the High Level Trigger algorithms, allowing highly improved trigger performance for the important signatures such as b-jets. In this paper, the architecture and the hardware development status of FT...

  17. Ultra-fast silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Sadrozinski, H. F.-W., E-mail: hartmut@scipp.ucsc.edu [Santa Cruz Institute for Particle Physics, UC Santa Cruz, Santa Cruz, CA 95064 (United States); Ely, S.; Fadeyev, V.; Galloway, Z.; Ngo, J.; Parker, C.; Petersen, B.; Seiden, A.; Zatserklyaniy, A. [Santa Cruz Institute for Particle Physics, UC Santa Cruz, Santa Cruz, CA 95064 (United States); Cartiglia, N.; Marchetto, F. [INFN Torino, Torino (Italy); Bruzzi, M.; Mori, R.; Scaringella, M.; Vinattieri, A. [University of Florence, Department of Physics and Astronomy, Sesto Fiorentino, Firenze (Italy)

    2013-12-01

    We propose to develop a fast, thin silicon sensor with gain capable to concurrently measure with high precision the space (∼10 μm) and time (∼10 ps) coordinates of a particle. This will open up new application of silicon detector systems in many fields. Our analysis of detector properties indicates that it is possible to improve the timing characteristics of silicon-based tracking sensors, which already have sufficient position resolution, to achieve four-dimensional high-precision measurements. The basic sensor characteristics and the expected performance are listed, the wide field of applications are mentioned and the required R and D topics are discussed. -- Highlights: •We are proposing thin pixel silicon sensors with 10's of picoseconds time resolution. •Fast charge collection is coupled with internal charge multiplication. •The truly 4-D sensors will revolutionize imaging and particle counting in many applications.

  18. Fast Moreau envelope computation I

    Science.gov (United States)

    Lucet, Yves

    2006-11-01

    The present article summarizes the state of the art algorithms to compute the discrete Moreau envelope, and presents a new linear-time algorithm, named NEP for NonExpansive Proximal mapping. Numerical comparisons between the NEP and two existing algorithms: The Linear-time Legendre Transform (LLT) and the Parabolic Envelope (PE) algorithms are performed. Worst-case time complexity, convergence results, and examples are included. The fast Moreau envelope algorithms first factor the Moreau envelope as several one-dimensional transforms and then reduce the brute force quadratic worst-case time complexity to linear time by using either the equivalence with Fast Legendre Transform algorithms, the computation of a lower envelope of parabolas, or, in the convex case, the non expansiveness of the proximal mapping.

  19. A fast meteor detection algorithm

    Science.gov (United States)

    Gural, P.

    2016-01-01

    A low latency meteor detection algorithm for use with fast steering mirrors had been previously developed to track and telescopically follow meteors in real-time (Gural, 2007). It has been rewritten as a generic clustering and tracking software module for meteor detection that meets both the demanding throughput requirements of a Raspberry Pi while also maintaining a high probability of detection. The software interface is generalized to work with various forms of front-end video pre-processing approaches and provides a rich product set of parameterized line detection metrics. Discussion will include the Maximum Temporal Pixel (MTP) compression technique as a fast thresholding option for feeding the detection module, the detection algorithm trade for maximum processing throughput, details on the clustering and tracking methodology, processing products, performance metrics, and a general interface description.

  20. Comparison of Calculation Models for Bucket Foundation in Sand

    DEFF Research Database (Denmark)

    Vaitkunaite, Evelina; Molina, Salvador Devant; Ibsen, Lars Bo

    The possibility of fast and rather precise preliminary offshore foundation design is desirable. The ultimate limit state of bucket foundation is investigated using three different geotechnical calculation tools: [Ibsen 2001] an analytical method, LimitState:GEO and Plaxis 3D. The study has focused...... on resultant bearing capacity of variously embedded foundation in sand. The 2D models, [Ibsen 2001] and LimitState:GEO can be used for the preliminary design because they are fast and result in a rather similar bearing capacity calculation compared with the finite element models of Plaxis 3D. The 2D models...... and their results are compared to the finite element model in Plaxis 3D in this article....

  1. A generalized approach for the calculation and automation of potentiometric titrations Part 2. Redox Titrations

    NARCIS (Netherlands)

    Stur, J.; Bos, M.; van der Linden, W.E.

    1984-01-01

    The very fast calculation procedure described earlier is applied to calculate the titration curves of complicated redox systems. The theory is extended slightly to cover inhomogeneous redox systems. Titrations of iodine or 2,6-dichloroindophenol with ascorbic acid are described. It is shown that cor

  2. Le logiciel FastCart

    OpenAIRE

    1986-01-01

    FastCart est un logiciel destiné à l'enseignement de la géographie. Il permet aux élèves de créer leurs propres documents d'études: histogrammes, cartes en hachures, cartes de classification de l'espace. Sa rapidité d'exécution et sa facilité d'utilisation en font un outil adapté aux exigences des enseignants.

  3. The FastGas detector

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, J.E.; Dalgliesh, R.M. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Duxbury, D.M., E-mail: dom.duxbury@stfc.ac.u [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Holt, S.A.; McPhail, D.J. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0QX (United Kingdom); Marsh, A.S. [Diamond Light Source LTD, Harwell Science and Innovation Campus, Diamond House, Chilton, Didcot, Oxfordshire, OX11 0DE (United Kingdom); Rhodes, N.J.; Schooneveld, E.M.; Spill, E.J.; Stephenson, R. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0QX (United Kingdom)

    2010-04-21

    The development and testing of the FastGas neutron detector is described. Based on a Gas Microstrip Chamber the aim of the project was to produce a high counting rate detector capable of replacing the existing {sup 3}He tubes for specular reflectometry, currently in use on the ISIS reflectometer instruments. The detector system is described together with results of neutron beam tests carried out at the ISIS spallation neutron source.

  4. Instrumentation of the fast detector

    CERN Document Server

    Barczyk, A.; Malgeri, L.; Casella, C.; Pohl, M.; Deiters, K.; Dick, P.; Berdugo, J.; Casaus, J.; Mana, C.; Marin, J.; Martinez, G.; Sanchez, E.; Willmott, C.

    2008-01-01

    The Fiber Active Scintillator Target (FAST) is an imaging particle detector intended for high precision muon lifetime measurement. This measurement will lead to a determination of the Fermi coupling constant (GF) with an uncertainty of 1 ppm, one order of magnitude better than the current world average. This contribution presents a description of the detector instrumentation and the first results, which have validated the design of the system.

  5. Programmable fast data acquisition system

    Science.gov (United States)

    Montebugnoli, S.; Bianchi, G.; Zoni, L.

    The goal of this work is to investigate the possibility to install on modern radiotelescopes a fast and programmable backend instead of several backends, each dedicated to a single acquisition task. Such an approach could lower the costs and make available a more compact and flexible back end. Exploiting the state-of-the-art of the FPGAs (Field Programmable Gate Arrays) and innovative architectures, a programmable system might be conceived.

  6. Fast regularized image interpolation method

    Institute of Scientific and Technical Information of China (English)

    Hongchen Liu; Yong Feng; Linjing Li

    2007-01-01

    The regularized image interpolation method is widely used based on the vector interpolation model in which down-sampling matrix has very large dimension and needs large storage consumption and higher computation complexity. In this paper, a fast algorithm for image interpolation based on the tensor product of matrices is presented, which transforms the vector interpolation model to matrix form. The proposed algorithm can extremely reduce the storage requirement and time consumption. The simulation results verify their validity.

  7. Verification of New Floating Capabilities in FAST v8: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, F.; Robertson, A.; Jonkman, J.; Hayman, G.

    2015-01-01

    In the latest release of NREL's wind turbine aero-hydro-servo-elastic simulation software, FAST v8, several new capabilities and major changes were introduced. FAST has been significantly altered to improve the simulator's modularity and to include new functionalities in the form of modules in the FAST v8 framework. This paper is focused on the improvements made for the modeling of floating offshore wind systems. The most significant change was to the hydrodynamic load calculation algorithms, which are embedded in the HydroDyn module. HydroDyn is now capable of applying strip-theory (via an extension of Morison's equation) at the member level for user-defined geometries. Users may now use a strip-theory-only approach for applying the hydrodynamic loads, as well as the previous potential-flow (radiation/diffraction) approach and a hybrid combination of both methods (radiation/diffraction and the drag component of Morison's equation). Second-order hydrodynamic implementations in both the wave kinematics used by the strip-theory solution and the wave-excitation loads in the potential-flow solution were also added to HydroDyn. The new floating capabilities were verified through a direct code-to-code comparison. We conducted a series of simulations of the International Energy Agency Wind Task 30 Offshore Code Comparison Collaboration Continuation (OC4) floating semisubmersible model and compared the wind turbine response predicted by FAST v8, the corresponding FAST v7 results, and results from other participants in the OC4 project. We found good agreement between FAST v7 and FAST v8 when using the linear radiation/diffraction modeling approach. The strip-theory-based approach inherently differs from the radiation/diffraction approach used in FAST v7 and we identified and characterized the differences. Enabling the second-order effects significantly improved the agreement between FAST v8 and the other OC4 participants.

  8. ATLAS Fast Physics Monitoring: TADA

    CERN Document Server

    Elsing, Markus; The ATLAS collaboration; Sabato, Gabriele; Kamioka, Shusei; Nairz, Armin Michael; Moyse, Edward; Gumpert, Christian

    2016-01-01

    The ATLAS Experiment at the LHC is recording data from proton-proton collisions with 13 TeV center-of-mass energy since spring 2015. The collaboration is using a fast physics monitoring framework (TADA) to automatically perform a broad range of fast searches for early signs of new physics and to monitor the data quality across the year with the full analysis level calibrations applied to the rapidly growing data. TADA is designed to provide fast feedback directly after the collected data has been fully calibrated and processed at the Tier-0. The system can monitor a large range of physics channels, offline data quality and physics performance quantities nearly final analysis level object calibrations. TADA output is available on a website accessible by the whole collaboration that gets updated twice a day with the data from newly processed runs. Hints of potentially interesting physics signals or performance issues identified in this way are reported to be followed up by physics or combined performance groups...

  9. ATLAS Fast Physics Monitoring: TADA

    CERN Document Server

    Sabato, Gabriele; The ATLAS collaboration

    2017-01-01

    The ATLAS experiment at the LHC is recording data from proton-proton collisions with 13 TeV center-of-mass energy since spring 2015. The collaboration is using a fast physics monitoring framework (TADA) to automatically perform a broad range of fast searches for early signs of new physics and to monitor the data quality across the year with the full analysis level calibrations applied to the rapidly growing data.TADA is designed to provide fast feedback directly after the collected data has been fully calibrated and processed at the Tier-0, the CERN Data Center. The system can monitor a large range of physics channels, offline data quality and physics performance quantities nearly final analysis level object calibrations. TADA output is available on a website accessible by the whole collaboration that gets updated twice a day with the data from newly processed runs. Hints of potentially interesting physics signals or performance issues identified in this way are reported to be followed up by physics or combin...

  10. Heterogeneous Transmutation Sodium Fast Reactor

    Energy Technology Data Exchange (ETDEWEB)

    S. E. Bays

    2007-09-01

    The threshold-fission (fertile) nature of Am-241 is used to destroy this minor actinide by capitalizing upon neutron capture instead of fission within a sodium fast reactor. This neutron-capture and its subsequent decay chain leads to the breeding of even neutron number plutonium isotopes. A slightly moderated target design is proposed for breeding plutonium in an axial blanket located above the active “fast reactor” driver fuel region. A parametric study on the core height and fuel pin diameter-to-pitch ratio is used to explore the reactor and fuel cycle aspects of this design. This study resulted in both non-flattened and flattened core geometries. Both of these designs demonstrated a high capacity for removing americium from the fuel cycle. A reactivity coefficient analysis revealed that this heterogeneous design will have comparable safety aspects to a homogeneous reactor of comparable size. A mass balance analysis revealed that the heterogeneous design may reduce the number of fast reactors needed to close the current once-through light water reactor fuel cycle.

  11. Fleet Assistance and Support Team (FAST) Lab

    Data.gov (United States)

    Federal Laboratory Consortium — The FAST team was established by PMA-264 for introduction of multistatic ASW systems into the Fleet.FAST provides Air ASW mission planning, tactics/tactical sensor...

  12. The Fast Simulation Chain for ATLAS

    CERN Document Server

    Basalaev, Artem; The ATLAS collaboration

    2017-01-01

    In order to generate the huge number of Monte Carlo events that will be required by the ATLAS experiment over the next several runs, a very fast simulation is critical. Fast detector simulation alone, however, is insufficient: with very high numbers of simultaneous proton-proton collisions expected in Run 3 and beyond, the digitization (detector response emulation) and event reconstruction time quickly become comparable to the time required for detector simulation. The ATLAS Fast Chain simulation has been developed to solve this problem. Modules are implemented for fast simulation, fast digitization, and fast track reconstruction. The application is sufficiently fast - several orders of magnitude faster than the standard simulation - that the simultaneous proton-proton collisions can be generated during the simulation job, so Pythia8 also runs concurrently with the rest of the algorithms. The Fast Chain has been built to be extremely modular and flexible, so that each sample can be custom-tailored to match th...

  13. Fleet Assistance and Support Team (FAST) Lab

    Data.gov (United States)

    Federal Laboratory Consortium — The FAST team was established by PMA-264 for introduction of multistatic ASW systems into the Fleet.FAST provides Air ASW mission planning, tactics/tactical sensor...

  14. The Fast Simulation Chain for ATLAS

    CERN Document Server

    Basalaev, Artem; The ATLAS collaboration

    2016-01-01

    In order to generate the huge number of Monte Carlo events that will be required by the ATLAS experiment over the next several runs, a very fast simulation is critical. Fast detector simulation alone, however, is insufficient: with very high numbers of simultaneous proton-proton collisions expected in Run 3 and beyond, the digitization (detector response emulation) and event reconstruction time quickly become comparable to the time required for detector simulation. The ATLAS Fast Chain simulation has been developed to solve this problem. Modules are implemented for fast simulation, fast digitization, and fast track reconstruction. The application is sufficiently fast -- several orders of magnitude faster than the standard simulation -- that the simultaneous proton-proton collisions can be generated during the simulation job, so Pythia8 also runs concurrently with the rest of the algorithms. The Fast Chain has been built to be extremely modular and flexible, so that each sample can be custom-tailored to match ...

  15. Fasting serum glucose and glycosylated hemoglobin level in obesity.

    Science.gov (United States)

    Das, R K; Nessa, A; Hossain, M A; Siddiqui, N I; Hussain, M A

    2014-04-01

    Obesity is a condition in which the body fat stores are increased to an extent which impairs health and leads to serious health consequences. The amount of body fat is difficult to measure directly, and is usually determined from an indirect measure - the body mass index (BMI). Increased BMI in obese persons is directly associated with an increase in metabolic disease, such as type 2 diabetes mellitus. This Analytical cross sectional study was undertaken to assess the relation between obesity and glycemic control of body by measuring fasting serum glucose and glycosylated hemoglobin. This study was carried out in the Department of Physiology, Mymensingh Medical College, Mymensingh from 1st July 2011 to 30th June 2012 on 120 equally divided male and female persons within the age range of 25 to 55 years. Age more than 55 years and less than 25 years and diagnosed case of Hypothyroidism, Cushing's syndrome, polycystic ovary, Antipsychotic drug user and regular steroid users were excluded. Non probability purposive type of sampling technique was used for selecting the study subjects. Measurement of body mass index was done as per procedure. Fasting serum glucose was estimated by glucose oxidase method and Glycosylated hemoglobin by Boronate Affinity method. Statistical analysis was done by SPSS (version 17.0). Data were expressed as Mean±SE and statistical significance of difference among the groups were calculated by unpaired student's 't' test and Pearson's correlation coefficient tests were done as applicable. The Mean±SE of fasting serum glucose was significant at 1% level (P value glycosylated hemoglobin level between control and study groups. But there was positive correlation within each group. Fasting serum glucose also showed a bit stronger positive correlation with BMI. Both obese male and female persons showed higher levels of fasting serum glucose and glycosylated hemoglobin. The observed positive correlation between BMI with fasting serum glucose and

  16. The digital backend of FAST

    Science.gov (United States)

    Yu, Xinying; Zhang, Xia; Duan, Ran; li, di; Hao, Jie

    2015-08-01

    The receiver system is an important part of FAST (Five-hundred-meter Aperture Spherical Radio Telescope) and plays a key role in determining the performance of the telescope.This research covers three major aspects: establishment of system synchronization and timestamps, field-programmable gate array (FPGA)-based data transmission and analysis, and the rear receiver monitoring system. We intend to combine the use of GPS and a frequency standard instrument with network access to Unix timestamps to form actual timestamps. The data are stored with timestamps that contain integer and fractional seconds to be precise and headers, which are primarily intended to distinguish the data from each other.The data analysis procedures includes converting the timestamp information to real-time information, and merging the 8 channels’ data conversion results into frequency and energy data using corresponding conversion formulae. We must develop tailored monitoring software for the FAST receiver to customize the data format and perform data transmission. Signals on the front-end and back-end of the receiver can be monitored and controlled by adjusting the parameters on the software to increase the flexibility of the receiver.Most operations are performed on FPGA board, which can be shown from the figure, including the analog-to-digital conversion (ADC), fast Fourier transform (FFT), and pulse per second (1PPS) and Unix timestamp access operations.When analog data arrive, we initialize two ADCs at a sampling rate of 3Gsps, following by 8-channel FFT parallel processing.In collaboration with the Institute of Automation, we have developed a custom FPGA board which we call "FDB"("FAST Digital Backend"). The board is integrated with two Virtex-6 and one Virtex-5 high-speed Xilinx chips. The main function of the two Virtex-6 devices is to run the FFT and PFB programs, whereas the main function of Virtex-5 is configuration of the board.This research is indispensable for realizing the

  17. Active noise control with fast array recursive least squares filters using a parallel implementation for numerical stability

    NARCIS (Netherlands)

    Berkhoff, A.P.; Ophem, S. van

    2015-01-01

    Noise reduction in feedforward active noise control systems with a rapidly changing primary path requires rapid convergence and fast tracking. This can be accomplished with a fast-array Kalman method which uses an efficient rotation matrix technique to calculate the filter parameters. However, finit

  18. Active noise control with fast array recursive least squares filters using a parallel implementation for numerical stability

    NARCIS (Netherlands)

    Berkhoff, Arthur P.; van Ophem, S.; Glorieux, C.

    2015-01-01

    Significant noise reduction in feedforward active noise control systems with a rapidly changing primary path requires rapid convergence and fast tracking performance. This can be accomplished with a fast-array Kalman method which uses an efficient rotation matrix technique to calculate the filter

  19. Active noise control with fast array recursive least squares filters using a parallel implementation for numerical stability

    NARCIS (Netherlands)

    Berkhoff, A.P.; Ophem, S. van

    2015-01-01

    Noise reduction in feedforward active noise control systems with a rapidly changing primary path requires rapid convergence and fast tracking. This can be accomplished with a fast-array Kalman method which uses an efficient rotation matrix technique to calculate the filter parameters. However,

  20. Fast Food Paradox: Freedom and Cultural Imperialism

    OpenAIRE

    Lelia Voinea

    2012-01-01

    Fast food is often regarded as a form of cultural imperialism. Fast-food products, originating in the U.S.A., are considered by the critics of this phenomenon as responsible for eroding the interest in local food traditions and affecting their continuity. Based on the results of some researches realized at international and national level, the paper highlights the main issues underlying young people preference for fast-food. The consumption of fast food is associated with the idea of independ...

  1. Fast calculation of DNMR spectra on CUDA-enabled graphics card.

    Science.gov (United States)

    Szalay, Zsófia; Rohonczy, János

    2011-05-01

    During the past few years, general-purpose graphics processing units (GPGPUs) have become rather popular in the high performance computing community. In this study, we present an implementation of the simulation of dynamic nuclear magnetic resonance (DNMR) spectra. The algorithm is based on the kinetic Monte Carlo method and therefore can benefit from the multithreaded architecture of the GPGPU. By careful optimization of the algorithm a 30-100-fold speed increase could be achieved.

  2. Gamma-rays and fast neutron responses calculations for personal electronic dosimetry purpose

    Science.gov (United States)

    Jung, M.; Teissier, C.; Siffert, P.

    2001-02-01

    Real-time dosimeters with small size N-type silicon diodes are proposed here for low-dose rate controls. Numerical simulations are used to predict the responses of various associated filters, neutron converters and sensors. The monitor is foreseen to work as a counter with acceptance cut-offs set on each individual pulse height. Discussions are undertaken against the minimal outline necessary to reach convenient measurement accuracies in unknown gamma-neutron fields.

  3. A Fast Stble Marching Scheme for Calculating Mixed Convection in a Vertical Rotating Annulus

    Institute of Scientific and Technical Information of China (English)

    Chao-MinZhang; Zeng-YuanGuo

    1993-01-01

    An iterative simultanous solution method is developed to efficiently solve the Newton-Raphson linear equation set for velocity in three dimensions,pressure and temperature,The proposed method is demonstrated for several cases of the thermal drive in a vertical rotating annulus,and is shown to be insensitive to dimensionless time step,requiring significantly less computational effort to converge to the desired accuracy than SIMPLEC,even for low Prandtl number fluid flows.

  4. Fast method of calculating a photorealistic hologram based on orthographic ray-wavefront conversion.

    Science.gov (United States)

    Igarashi, Shunsuke; Nakamura, Tomoya; Yamaguchi, Masahiro

    2016-04-01

    A computer-generated hologram based on ray-wavefront conversion can reconstruct photorealistic three-dimensional (3D) images containing deep virtual objects and complicated physical phenomena; however, the required computational cost has been a problem that needs to be solved. In this Letter, we introduce the concept of an orthographic projection in the ray-wavefront conversion technique for reducing the computational cost without degrading the image quality. In the proposed method, plane waves with angular spectra of the object are obtained via orthographic ray sampling and Fourier transformation, and only the plane waves incident on the hologram plane are numerically propagated. We verified this accelerated computational method theoretically and experimentally, and demonstrated optical reconstruction of a deep 3D image in which the effects of occlusions, transmission, refraction, and reflection were faithfully reproduced.

  5. Fast calculation of magnetic field distribution in magnetic gear for high torque application

    DEFF Research Database (Denmark)

    Zhang, Xiaoxu; Liu, Xiao; Song, Zhanfeng

    2016-01-01

    For applications demanding high torque and high reliability transmission, coaxial magnetic gear (CMG) may be a promising substitute of the mechanical gearbox. However, with the increasing of unit capacity, CMG tends to have a big size with large pole number, which would lead to heavy computation...

  6. Stationary Liquid Fuel Fast Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Won Sik [Purdue Univ., West Lafayette, IN (United States); Grandy, Andrew [Argonne National Lab. (ANL), Argonne, IL (United States); Boroski, Andrew [Argonne National Lab. (ANL), Argonne, IL (United States); Krajtl, Lubomir [Argonne National Lab. (ANL), Argonne, IL (United States); Johnson, Terry [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-30

    For effective burning of hazardous transuranic (TRU) elements of used nuclear fuel, a transformational advanced reactor concept named SLFFR (Stationary Liquid Fuel Fast Reactor) was proposed based on stationary molten metallic fuel. The fuel enters the reactor vessel in a solid form, and then it is heated to molten temperature in a small melting heater. The fuel is contained within a closed, thick container with penetrating coolant channels, and thus it is not mixed with coolant nor flow through the primary heat transfer circuit. The makeup fuel is semi- continuously added to the system, and thus a very small excess reactivity is required. Gaseous fission products are also removed continuously, and a fraction of the fuel is periodically drawn off from the fuel container to a processing facility where non-gaseous mixed fission products and other impurities are removed and then the cleaned fuel is recycled into the fuel container. A reference core design and a preliminary plant system design of a 1000 MWt TRU- burning SLFFR concept were developed using TRU-Ce-Co fuel, Ta-10W fuel container, and sodium coolant. Conservative design approaches were adopted to stay within the current material performance database. Detailed neutronics and thermal-fluidic analyses were performed to develop a reference core design. Region-dependent 33-group cross sections were generated based on the ENDF/B-VII.0 data using the MC2-3 code. Core and fuel cycle analyses were performed in theta-r-z geometries using the DIF3D and REBUS-3 codes. Reactivity coefficients and kinetics parameters were calculated using the VARI3D perturbation theory code. Thermo-fluidic analyses were performed using the ANSYS FLUENT computational fluid dynamics (CFD) code. Figure 0.1 shows a schematic radial layout of the reference 1000 MWt SLFFR core, and Table 0.1 summarizes the main design parameters of SLFFR-1000 loop plant. The fuel container is a 2.5 cm thick cylinder with an inner radius of 87.5 cm. The fuel

  7. Fast neutron imaging device and method

    Science.gov (United States)

    Popov, Vladimir; Degtiarenko, Pavel; Musatov, Igor V.

    2014-02-11

    A fast neutron imaging apparatus and method of constructing fast neutron radiography images, the apparatus including a neutron source and a detector that provides event-by-event acquisition of position and energy deposition, and optionally timing and pulse shape for each individual neutron event detected by the detector. The method for constructing fast neutron radiography images utilizes the apparatus of the invention.

  8. Fast Foods, Organic Foods, Fad Diets

    Science.gov (United States)

    There is no standard definition of fast food. Generally, fast food is eaten without cutlery, and fast-food restaurants have no wait staff. Failure to have a standardized definition makes it difficult to compare studies. Foods available outside the home tend to be high in energy and fat compared w...

  9. Investigation of fast ion pressure effects in ASDEX Upgrade by spectral MSE measurements

    Science.gov (United States)

    Reimer, René; Dinklage, Andreas; Wolf, Robert; Dunne, Mike; Geiger, Benedikt; Hobirk, Jörg; Reich, Matthias; ASDEX Upgrade Team; McCarthy, Patrick J.

    2017-04-01

    High precision measurements of fast ion effects on the magnetic equilibrium in the ASDEX Upgrade tokamak have been conducted in a high-power (10 MW) neutral-beam injection discharge. An improved analysis of the spectral motional Stark effect data based on forward-modeling, including the Zeeman effect, fine-structure and non-statistical sub-level distribution, revealed changes in the order of 1% in |B| . The results were found to be consistent with results from the equilibrium solver CLISTE. The measurements allowed us to derive the fast ion pressure fraction to be Δ {{p}\\text{FI}}/{{p}\\text{mhd}}≈ 10 % and variations of the fast ion pressure are consistent with calculations of the transport code TRANSP. The results advance the understanding of fast ion confinement and magneto-hydrodynamic stability in the presence of fast ions.

  10. Fast dose optimization for rotating shield brachytherapy.

    Science.gov (United States)

    Cho, Myung; Wu, Xiaodong; Dadkhah, Hossein; Yi, Jirong; Flynn, Ryan T; Kim, Yusung; Xu, Weiyu

    2017-07-26

    To provide a fast computational method, based on the proximal graph solver (POGS) - a convex optimization solver using the alternating direction method of multipliers (ADMM), for calculating an optimal treatment plan in rotating shield brachytherapy (RSBT). RSBT treatment planning has more degrees of freedom than conventional high-dose-rate brachytherapy due to the addition of emission direction, and this necessitates a fast optimization technique to enable clinical usage. The multi-helix RSBT (H-RSBT) delivery technique(1) was investigated for five representative cervical cancer patients. Treatment plans were generated for all patients using the POGS method and the commercially available solver IBM ILOG CPLEX(2) . The rectum, bladder, sigmoid colon, high-risk clinical target volume (HRCTV), and HR-CTV boundary were the structures included in our optimization, which applied an asymmetric dose-volume optimization with smoothness control. Dose calculation resolution was 1X1X3 mm(3) for all cases. The H-RSBT applicator had 6 helices, with 33:3 mm of translation along the applicator per helical rotation and 1:7 mm spacing between dwell positions, yielding 17.5° emission angle spacing per 5 mm along the applicator. For each patient, HR-CTV D90, HR-CTV D100, rectum D2cc, sigmoid D2cc, and bladder D2cc matched within 1% for CPLEX and POGS methods. Also, similar EQD2 values between CPLEX and POGS methods were obtained. POGS was around 18 times faster than CPLEX. Over all patients, total optimization times were 32.1-65.4 seconds for CPLEX and 2.1-3.9 seconds for POGS. POGS reduced treatment plan optimization time approximately 18 times for RSBT with similar HR-CTV D90, organ at risk (OAR) D2cc values, and EQD2 values compared to CPLEX, which is significant progress toward clinical translation of RSBT. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  11. Accuracy of Non-Fasting Lipid Profile for the Assessment of Lipoprotein Coronary Risk.

    Science.gov (United States)

    Fatima, Safia; Ijaz, Aamir; Sharif, Tariq Bin; Khan, Dilshad Ahmad; Siddique, Amer

    2016-12-01

    To determine the diagnostic accuracy of non-fasting lipid profile in the diagnosis of hyperlipidemia, taking fasting lipid profile as gold standard, in adult population. Cross-sectional validation study. Department of Chemical Pathology and Endocrinology, Armed Forces Institute of Pathology, Rawalpindi, from July to December 2014. One hundred seventy-five adult patients coming for fasting lipid profile were included; their non-fasting samples were taken on the next day. Patients on anti-cholesterol treatment and indoor patients were excluded. Total cholesterol (TC), high density lipoprotein-cholestrol (HDL-C), and triglycerides were measured by direct enzymatic colorimetric method by Modular p-800®. Low density lipoprotein-cholesterol (LDL-C) was calculated by Friedewald's formula, but when triglyceride was greater than 4.5 mmol/l, then LDL-C was measured directly by homogenous enzymatic colorimetric method. Non-HDL-C was calculated by simple equation, i.e. TC-HDL-C. Non-fasting lipid profile had 93% specificity , 51% sensitivity, 94% positive predictive value and 49% negative predictive value; and 65% accuracy with 7.28 positive likelihood ratio and 0.52 negative likelihood ratio. Non-fasting TC and non-HDL-C were significantly higher than fasting TC and non-HDL-C by mean difference of 0.2 mmol/l each with p=0.001 and p=0.004, respectively. Fasting and non fasting HDL-C are comparable to each other with mean difference of 0.01 mmol/l (p=0.745). Receiver operating curve (ROC) of non-fasting non-HDL-C showed 0.804 (95%CI (0.738-0.870), (p=0.000) area under the curve (AUC) indicating that it was a significant test for ruling out hyperlipidemia. Bland-Altmann plot showed a significant difference between non-fasting, non-HDL-C and fasting LDL-C and non-fasting, non-HDL-C -0.087540 with bias -0.00109; therefore, these cannot be alternative to each other. Diagnostic accuracy of non-fasting lipid profile was found significantly higher than fasting lipid profile (p=0

  12. Fast Algorithm of Numerical Solutions for Strong Nonlinear Partial Differential Equations

    Directory of Open Access Journals (Sweden)

    Tongjing Liu

    2014-07-01

    Full Text Available Because of a high mobility ratio in the chemical and gas flooding for oil reservoirs, the problems of numerical dispersion and low calculation efficiency also exist in the common methods, such as IMPES and adaptive implicit methods. Therefore, the original calculation process, “one-step calculation for pressure and multistep calculation for saturation,” was improved by introducing a velocity item and using the fractional flow in a direction to calculate the saturation. Based on these developments, a new algorithm of numerical solution for “one-step calculation for pressure, one-step calculation for velocity, and multi-step calculation for fractional flow and saturation” was obtained, and the convergence condition for the calculation of saturation was also proposed. The simulation result of a typical theoretical model shows that the nonconvergence occurred for about 6,000 times in the conventional algorithm of IMPES, and a high fluctuation was observed in the calculation steps. However, the calculation step of the fast algorithm was stabilized for 0.5 d, indicating that the fast algorithm can avoid the nonconvergence caused by the saturation that was directly calculated by pressure. This has an important reference value in the numerical simulations of chemical and gas flooding for oil reservoirs.

  13. EOSPEC: a complementary toolbox for MODTRAN calculations

    Science.gov (United States)

    Dion, Denis

    2016-09-01

    For more than a decade, Defence Research and Development Canada (DRDC) has been developing a Library of computer models for the calculations of atmospheric effects on EO-IR sensor performances. The Library, called EOSPEC-LIB (EO-IR Sensor PErformance Computation LIBrary) has been designed as a complement to MODTRAN, the radiative transfer code developed by the Air Force Research Laboratory and Spectral Science Inc. in the USA. The Library comprises modules for the definition of the atmospheric conditions, including aerosols, and provides modules for the calculation of turbulence and fine refraction effects. SMART (Suite for Multi-resolution Atmospheric Radiative Transfer), a key component of EOSPEC, allows one to perform fast computations of transmittances and radiances using MODTRAN through a wide-band correlated-k computational approach. In its most recent version, EOSPEC includes a MODTRAN toolbox whose functions help generate in a format compatible to MODTRAN 5 and 6 atmospheric and aerosol profiles, user-defined refracted optical paths and inputs for configuring the MODTRAN sea radiance (BRDF) model. The paper gives an overall description of the EOSPEC features and capacities. EOSPEC provides augmented capabilities for computations in the lower atmosphere, and for computations in maritime environments.

  14. LIKEDM: Likelihood calculator of dark matter detection

    Science.gov (United States)

    Huang, Xiaoyuan; Tsai, Yue-Lin Sming; Yuan, Qiang

    2017-04-01

    With the large progress in searches for dark matter (DM) particles with indirect and direct methods, we develop a numerical tool that enables fast calculations of the likelihoods of specified DM particle models given a number of observational data, such as charged cosmic rays from space-borne experiments (e.g., PAMELA, AMS-02), γ-rays from the Fermi space telescope, and underground direct detection experiments. The purpose of this tool - LIKEDM, likelihood calculator for dark matter detection - is to bridge the gap between a particle model of DM and the observational data. The intermediate steps between these two, including the astrophysical backgrounds, the propagation of charged particles, the analysis of Fermi γ-ray data, as well as the DM velocity distribution and the nuclear form factor, have been dealt with in the code. We release the first version (v1.0) focusing on the constraints from indirect detection of DM with charged cosmic and gamma rays. Direct detection will be implemented in the next version. This manual describes the framework, usage, and related physics of the code.

  15. Development of fast neutron pinhole camera using nuclear emulsion for neutron emission profile measurement in KSTAR

    Science.gov (United States)

    Izumi, Y.; Tomita, H.; Nakayama, Y.; Hayashi, S.; Morishima, K.; Isobe, M.; Cheon, M. S.; Ogawa, K.; Nishitani, T.; Naka, T.; Nakano, T.; Nakamura, M.; Iguchi, T.

    2016-11-01

    We have developed a compact fast neutron camera based on a stack of nuclear emulsion plates and a pinhole collimator. The camera was installed at J-port of Korea superconducting tokamak advanced research at National Fusion Research Institute, Republic of Korea. Fast neutron images agreed better with calculated ones based on Monte Carlo neutron simulation using the uniform distribution of Deuterium-Deuterium (DD) neutron source in a torus of 40 cm radius.

  16. Fast ion behavior during neutral beam injection in ATF

    Energy Technology Data Exchange (ETDEWEB)

    Wade, M.R.; Thomas, C.E.; Colchin, R.J.; Rome, J.A.; England, A.C.; Fowler, R.H. [Oak Ridge National Lab., TN (United States); Aceto, S.C. [Rensselaer Polytechnic Inst., Troy, NY (United States)

    1993-09-01

    In stellarators, single-particle confinement properties can be more complex than in their tokamak counterparts. Fast-ion behavior in tokamaks has been well characterized through an abundance of measurements on various devices and in general has been shown to be consistent with classical slowing-down theory, although anomalous ion behavior has been observed during intense beam injection in ISX-B, during fishbone instabilities in PDX, and in experiments on TFR. In contrast, fast ion behavior in stellarators is not as wel established experimentally with the primary experiments to date focusing o near-perpendicular or perpendicular neutral beam injection (NBI) on the Wendelstein 7-A stellarator (91 and Heliotron-E. This paper addresses fast-ion confinement properties in a large-aspect-ratio, moderate-shear stellarator, the Advanced Toroidal Facility, during tangential NBI. The primary data used in this study are the experimentally measured energy spectra of charge-exchange neutrals escaping from the plasma, using a two-dimensional scanning neutral particle analyzer. This diagnostic method is well established, having been used on several devices since the early 1970`s. Various aspects of fast-ion behavior are investigated by comparing these data with computed theoretical spectra based on energeticion distributions derived from the fastion Fokker-Planck equation. Ion orbits are studied by computer orbit following, by the computation of J* surfaces, and by Monte Carlo calculations.

  17. A new fast direct solver for the boundary element method

    Science.gov (United States)

    Huang, S.; Liu, Y. J.

    2017-04-01

    A new fast direct linear equation solver for the boundary element method (BEM) is presented in this paper. The idea of the new fast direct solver stems from the concept of the hierarchical off-diagonal low-rank matrix. The hierarchical off-diagonal low-rank matrix can be decomposed into the multiplication of several diagonal block matrices. The inverse of the hierarchical off-diagonal low-rank matrix can be calculated efficiently with the Sherman-Morrison-Woodbury formula. In this paper, a more general and efficient approach to approximate the coefficient matrix of the BEM with the hierarchical off-diagonal low-rank matrix is proposed. Compared to the current fast direct solver based on the hierarchical off-diagonal low-rank matrix, the proposed method is suitable for solving general 3-D boundary element models. Several numerical examples of 3-D potential problems with the total number of unknowns up to above 200,000 are presented. The results show that the new fast direct solver can be applied to solve large 3-D BEM models accurately and with better efficiency compared with the conventional BEM.

  18. An alternative observable to estimate keff in fast ADS

    CERN Document Server

    Chersola, Davide; Ripani, Marco; Saracco, Paolo

    2016-01-01

    In this paper we examine an alternative method for determining the neutron multiplication factor keff in fast subcritical reactors, based on the observable obtained by calculating the ratio between the ``fast`` component of the neutron flux (in this case by fast we mean neutrons with kinetic energy above 0.5 MeV) and the whole flux at all energies. The assumption behind the present study was that the above mentioned observable would be only sensitive to keff, provided a peripheral fuel rod is considered (i.e. far from the neutron source in subcritical systems) and keff is sufficiently high. Indeed, our results show that, for keff> 0.7, the ratio calculated for LFR or GFR models turns out to show a quite similar trend well approximated by a straight line, while a different slope is observed for a sodium reactor. In our opinion, the results obtained show that such observable, after appropriate calibrations on the real systems under consideration, may be used for determining keff in all operational conditions, i...

  19. Point Scattered Function (PScF) for fast neutron radiography

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Mohamed H. [Nuclear and Radiation Engineering Department, Alexandria University, Alexandria 21544 (Egypt)], E-mail: mhmheg@yahoo.com

    2009-08-01

    Fast neutron radiography opened up a new range of possibilities to image extremely dense objects. The removal of the scattering effect is one of the most challenging problems in neutron imaging. Neutron scattering in fast neutron radiography did not receive much attention compared with X-ray and thermal neutron radiography. The purpose of this work is to investigate the behavior of the Point Scattered Function (PScF) as applied in fast neutron radiography. The PScF was calculated using MCNP as a spatial distribution of scattered neutrons over the detector surface for one emitting source element. Armament and explosives materials, namely, Rifle steel, brass, aluminum and trinitrotoluene (TNT) were simulated. Effect of various sample thickness and sample-to-detector distance were considered. Simulated sample geometries included a slab with varying thickness, a sphere with varying radii, and a cylinder with varying base radii. Different neutron sources, namely, Cf-252, DT as well as DD neutron sources were considered. Neutron beams with zero degree divergence angle; and beams with varying angles related to the normal to the source plane were simulated. Curve fitting of the obtained PScF, in the form of Gaussian function, were given to be used in future work using image restoration codes. Analytical representation of the height as well as the Full Width at Half Maximum (FWHM) of the obtained Gaussian functions eliminates the need to calculate the PScF for sample parameters that were not investigated in this study.

  20. A novel fast full inversion based breast ultrasound elastography technique.

    Science.gov (United States)

    Karimi, Hirad; Fenster, Aaron; Samani, Abbas

    2013-04-07

    Cancer detection and classification have been the focus of many imaging and therapeutic research studies. Elastography is a non-invasive technique to visualize suspicious soft tissue areas where tissue stiffness is used as image contrast mechanism. In this study, a breast ultrasound elastography system including software and hardware is proposed. Unlike current elastography systems that image the tissue strain and present it as an approximation to relative tissue stiffness, this system is capable of imaging the breast absolute Young's modulus in fast fashion. To improve the quality of elastography images, a novel system consisting of two load cells has been attached to the ultrasound probe. The load cells measure the breast surface forces to be used for calculating the tissue stress distribution throughout the breast. To facilitate fast imaging, this stress calculation is conducted by an accelerated finite element method. Acquired tissue displacements and surface force data are used as input to the proposed Young's modulus reconstruction technique. Numerical and tissue mimicking phantom studies were conducted for validating the proposed system. These studies indicated that fast imaging of breast tissue absolute Young's modulus using the proposed ultrasound elastography system is feasible. The tissue mimicking phantom study indicated that the system is capable of providing reliable absolute Young's modulus values for both normal tissue and tumour as the maximum Young's modulus reconstruction error was less than 6%. This demonstrates that the proposed system has a good potential to be used for clinical breast cancer assessment.

  1. A novel fast full inversion based breast ultrasound elastography technique

    Science.gov (United States)

    Karimi, Hirad; Fenster, Aaron; Samani, Abbas

    2013-04-01

    Cancer detection and classification have been the focus of many imaging and therapeutic research studies. Elastography is a non-invasive technique to visualize suspicious soft tissue areas where tissue stiffness is used as image contrast mechanism. In this study, a breast ultrasound elastography system including software and hardware is proposed. Unlike current elastography systems that image the tissue strain and present it as an approximation to relative tissue stiffness, this system is capable of imaging the breast absolute Young’s modulus in fast fashion. To improve the quality of elastography images, a novel system consisting of two load cells has been attached to the ultrasound probe. The load cells measure the breast surface forces to be used for calculating the tissue stress distribution throughout the breast. To facilitate fast imaging, this stress calculation is conducted by an accelerated finite element method. Acquired tissue displacements and surface force data are used as input to the proposed Young’s modulus reconstruction technique. Numerical and tissue mimicking phantom studies were conducted for validating the proposed system. These studies indicated that fast imaging of breast tissue absolute Young’s modulus using the proposed ultrasound elastography system is feasible. The tissue mimicking phantom study indicated that the system is capable of providing reliable absolute Young’s modulus values for both normal tissue and tumour as the maximum Young’s modulus reconstruction error was less than 6%. This demonstrates that the proposed system has a good potential to be used for clinical breast cancer assessment.

  2. Comparison of Fast-Food and Non-Fast-Food Children's Menu Items

    Science.gov (United States)

    Serrano, Elena L.; Jedda, Virginia B.

    2009-01-01

    Objective: Compare the macronutrient content of children's meals sold by fast-food restaurants (FFR) and non-fast-food restaurants (NFF). Design: All restaurants within the designated city limits were surveyed. Non-fast-food children's meals were purchased, weighed, and analyzed using nutrition software. All fast-food children's meals were…

  3. Global nuclear-structure calculations

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, P.; Nix, J.R.

    1990-04-20

    The revival of interest in nuclear ground-state octupole deformations that occurred in the 1980's was stimulated by observations in 1980 of particularly large deviations between calculated and experimental masses in the Ra region, in a global calculation of nuclear ground-state masses. By minimizing the total potential energy with respect to octupole shape degrees of freedom in addition to {epsilon}{sub 2} and {epsilon}{sub 4} used originally, a vastly improved agreement between calculated and experimental masses was obtained. To study the global behavior and interrelationships between other nuclear properties, we calculate nuclear ground-state masses, spins, pairing gaps and {Beta}-decay and half-lives and compare the results to experimental qualities. The calculations are based on the macroscopic-microscopic approach, with the microscopic contributions calculated in a folded-Yukawa single-particle potential.

  4. A computer code for beam optics calculation--third order approximation

    Institute of Scientific and Technical Information of China (English)

    L(U) Jianqin; LI Jinhai

    2006-01-01

    To calculate the beam transport in the ion optical systems accurately, a beam dynamics computer program of third order approximation is developed. Many conventional optical elements are incorporated in the program. Particle distributions of uniform type or Gaussian type in the ( x, y, z ) 3D ellipses can be selected by the users. The optimization procedures are provided to make the calculations reasonable and fast. The calculated results can be graphically displayed on the computer monitor.

  5. Isochoric implosions for fast ignition

    Energy Technology Data Exchange (ETDEWEB)

    Clark, D S; Tabak, M

    2006-06-05

    Fast Ignition (FI) exploits the ignition of a dense, uniform fuel assembly by an external energy source to achieve high gain. In conventional ICF implosions, however, the fuel assembles as a dense shell surrounding a low density, high-pressure hotspot. Such configurations are far from optimal for FI. Here, it is shown that a self-similar spherical implosion of the type originally studied by Guderley [Luftfahrtforschung 19, 302 (1942).] may be employed to implode a dense, quasi-uniform fuel assembly with minimal energy wastage in forming a hotspot. A scheme for realizing these specialized implosions in a practical ICF target is also described.

  6. Fast, efficient lossless data compression

    Science.gov (United States)

    Ross, Douglas

    1991-01-01

    This paper presents lossless data compression and decompression algorithms which can be easily implemented in software. The algorithms can be partitioned into their fundamental parts which can be implemented at various stages within a data acquisition system. This allows for efficient integration of these functions into systems at the stage where they are most applicable. The algorithms were coded in Forth to run on a Silicon Composers Single Board Computer (SBC) using the Harris RTX2000 Forth processor. The algorithms require very few system resources and operate very fast. The performance of the algorithms with the RTX enables real time data compression and decompression to be implemented for a wide range of applications.

  7. ATLAS FTK Fast Track Trigger

    CERN Document Server

    Iizawa, T; The ATLAS collaboration

    2014-01-01

    The Fast TracKer (FTK) will perform global track reconstruction after each Level-1 trigger accept signal to enable the software-based higher level trigger to have early access to tracking information. FTK is a dedicated processor based on a mixture of advanced technologies. Modern, powerful Field Programmable Gate Arrays (FPGAs) form an important part of the system architecture, and the large level of computing power required for pattern recognition is provided by incorporating standard-cell ASICs named Associative Memory (AM). Motivation and the architecture of the FTK system will be presented, and the status of hardware and simulation will be following.

  8. Fast-acting valve actuator

    Science.gov (United States)

    Cho, Nakwon

    1980-01-01

    A fast-acting valve actuator utilizes a spring driven pneumatically loaded piston to drive a valve gate. Rapid exhaust of pressurized gas from the pneumatically loaded side of the piston facilitates an extremely rapid piston stroke. A flexible selector diaphragm opens and closes an exhaust port in response to pressure differentials created by energizing and de-energizing a solenoid which controls the pneumatic input to the actuator as well as selectively providing a venting action to one side of the selector diaphragm.

  9. Fast global sequence alignment technique

    KAUST Repository

    Bonny, Mohamed Talal

    2011-11-01

    Bioinformatics database is growing exponentially in size. Processing these large amount of data may take hours of time even if super computers are used. One of the most important processing tool in Bioinformatics is sequence alignment. We introduce fast alignment algorithm, called \\'Alignment By Scanning\\' (ABS), to provide an approximate alignment of two DNA sequences. We compare our algorithm with the wellknown sequence alignment algorithms, the \\'GAP\\' (which is heuristic) and the \\'Needleman-Wunsch\\' (which is optimal). The proposed algorithm achieves up to 51% enhancement in alignment score when it is compared with the GAP Algorithm. The evaluations are conducted using different lengths of DNA sequences. © 2011 IEEE.

  10. CALCULATION OF LASER CUTTING COSTS

    Directory of Open Access Journals (Sweden)

    Bogdan Nedic

    2016-09-01

    Full Text Available The paper presents description methods of metal cutting and calculation of treatment costs based on model that is developed on Faculty of mechanical engineering in Kragujevac. Based on systematization and analysis of large number of calculation models of cutting with unconventional methods, mathematical model is derived, which is used for creating a software for calculation costs of metal cutting. Software solution enables resolving the problem of calculating the cost of laser cutting, comparison' of costs made by other unconventional methods and provides documentation that consists of reports on estimated costs.

  11. Stability properties and fast ion confinement of hybrid tokamak plasma configurations

    Science.gov (United States)

    Graves, J. P.; Brunetti, D.; Pfefferle, D.; Faustin, J. M. P.; Cooper, W. A.; Kleiner, A.; Lanthaler, S.; Patten, H. W.; Raghunathan, M.

    2015-11-01

    In hybrid scenarios with flat q just above unity, extremely fast growing tearing modes are born from toroidal sidebands of the near resonant ideal internal kink mode. New scalings of the growth rate with the magnetic Reynolds number arise from two fluid effects and sheared toroidal flow. Non-linear saturated 1/1 dominant modes obtained from initial value stability calculation agree with the amplitude of the 1/1 component of a 3D VMEC equilibrium calculation. Viable and realistic equilibrium representation of such internal kink modes allow fast ion studies to be accurately established. Calculations of MAST neutral beam ion distributions using the VENUS-LEVIS code show very good agreement of observed impaired core fast ion confinement when long lived modes occur. The 3D ICRH code SCENIC also enables the establishment of minority RF distributions in hybrid plasmas susceptible to saturated near resonant internal kink modes.

  12. Concept and canons of fasting in Ayurveda

    Directory of Open Access Journals (Sweden)

    H Shripathi Adiga

    2013-03-01

    Full Text Available Ayurveda, manoeuvres mankind to head a healthy life in order to pursue four-fold bliss. With a view to combat physical and mental annoyances, classics have explicated two-fold therapeutic modalities; langhana/depletion and brihmana/nourishing. Upavasa /fasting is one among ten depletion therapies explained. It is envisioned at all three levels of Ayurvedic therapies- rational/objectively planned, psychological, and spiritual. Fasting is reckoned to be refraining from all forms of food intake for a given period, under supervision of a qualified physician. Acharya Charaka advocates fasting in diseases of milder intensity, in those due to aama (metabolic toxin, after purificatory procedures. Fasting person should avoid beautifying oneself, day sleep, sexual acts, and feasting prior and ulterior to fasting. Fasting is contraindicated in very young, elderly, emaciated, pregnant lady, and shortly after strenuous exercise. The principle avers that fasting kindles metabolic/digestive fire which, in absence of food, brings about paachana of vitiated doshas, thereby riposting health. Sound fasting ensues proper elimination of excretory wastes, clear belch, sweat, and taste for food. Benefits of fasting include lucidity of sense organs, lightness of body and mind, control of diseases, and enthusiasm. Yoga Shastra describes fasting with respect to three levels of food: physical, impressions, and associations and a means to unite three bodies: astral, physical, and causal. Ayurveda thus advocates fasting depending upon the dosha, agni, vaya, kala, and bala of the individual, as a preventive as well as therapeutic modality.

  13. Energy-dense fast food products cost less: an observational study of the energy density and energy cost of Australian fast foods.

    Science.gov (United States)

    Wellard, Lyndal; Havill, Michelle; Hughes, Clare; Watson, Wendy L; Chapman, Kathy

    2015-12-01

    To examine the association between energy cost and energy density of fast food products. Twenty Sydney outlets of the five largest fast food chains were surveyed four times. Price and kilojoule data were collected for all limited-time-only menu items (n=54) and a sample of standard items (n=67). Energy cost ($/kilojoule) and energy density (kilojoules/gram) of menu items were calculated. There was a significant inverse relationship between menu item energy density and energy cost (ppricing of larger serve sizes, or change defaults in meals to healthier options. More research is required to determine the most effective strategy to reduce the negative impact of fast food on the population's diet. Current pricing in the fast food environment may encourage unhealthier purchases. © 2015 Public Health Association of Australia.

  14. Body composition changes associated with fasted versus non-fasted aerobic exercise

    OpenAIRE

    Schoenfeld, Brad Jon; Aragon, Alan Albert; Wilborn, Colin D; Krieger, James W.; Sonmez, Gul T

    2014-01-01

    It has been hypothesized that performing aerobic exercise after an overnight fast accelerates the loss of body fat. The purpose of this study was to investigate changes in fat mass and fat-free mass following four weeks of volume-equated fasted versus fed aerobic exercise in young women adhering to a hypocaloric diet. Twenty healthy young female volunteers were randomly assigned to 1 of 2 experimental groups: a fasted training (FASTED) group that performed exercise after an overnight fast (n ...

  15. GRIFFIN's Fast-Timing Array

    Science.gov (United States)

    Olaizola, Bruno; Griffin Collaboration

    2016-09-01

    The Gamma-Ray Infrastructure For Fundamental Investigations of Nuclei (GRIFFIN) is the new β-decay spectrometer facility at TRIUMF-ISAC. Consists of an array of 16 large-volume HPGe clover detectors with an unparalleled efficiency of 19% at 1.33 MeV. Its strongest advantage is the versatility of the ancillary detectors that can be coupled to the main array to tag on β particles, neutrons or precisely measure conversion electron spectra. An ancillary array of 8 LaBr3(Ce) detectors for γ-rays and a fast plastic scintillator for β-particles has been optimized for fast-timing experiments with GRIFFIN. The 51 mm x 51 mm cylindrical LaBr3(Ce) crystals are coupled to Hamamatsu R2083 photomultipliers. Timing resolutions as good as FWHM 200 ps and time-walks below +/- 30 ps have been obtained for individual crystals using analog electronics. There is also an ongoing project to develop an active BGO shield for the LaBr3(Ce) crystals. The LaBr3(Ce) array commissioning experiment to measure the 145,146Cs decay to 145,146Ba will test its capabilities over a wide range of lifetimes. Preliminary results on the lifetimes of some of the low-laying states will be presented.

  16. RCD+: Fast loop modeling server.

    Science.gov (United States)

    López-Blanco, José Ramón; Canosa-Valls, Alejandro Jesús; Li, Yaohang; Chacón, Pablo

    2016-07-08

    Modeling loops is a critical and challenging step in protein modeling and prediction. We have developed a quick online service (http://rcd.chaconlab.org) for ab initio loop modeling combining a coarse-grained conformational search with a full-atom refinement. Our original Random Coordinate Descent (RCD) loop closure algorithm has been greatly improved to enrich the sampling distribution towards near-native conformations. These improvements include a new workflow optimization, MPI-parallelization and fast backbone angle sampling based on neighbor-dependent Ramachandran probability distributions. The server starts by efficiently searching the vast conformational space from only the loop sequence information and the environment atomic coordinates. The generated closed loop models are subsequently ranked using a fast distance-orientation dependent energy filter. Top ranked loops are refined with the Rosetta energy function to obtain accurate all-atom predictions that can be interactively inspected in an user-friendly web interface. Using standard benchmarks, the average root mean squared deviation (RMSD) is 0.8 and 1.4 Å for 8 and 12 residues loops, respectively, in the challenging modeling scenario in where the side chains of the loop environment are fully remodeled. These results are not only very competitive compared to those obtained with public state of the art methods, but also they are obtained ∼10-fold faster. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  17. ATLAS FTK: Fast Track Trigger

    CERN Document Server

    Volpi, Guido; The ATLAS collaboration

    2015-01-01

    An overview of the ATLAS Fast Tracker processor is presented, reporting the design of the system, its expected performance, and the integration status. The next LHC runs, with a significant increase in instantaneous luminosity, will provide a big challenge to the trigger and data acquisition systems of all the experiments. An intensive use of the tracking information at the trigger level will be important to keep high efficiency in interesting events, despite the increase in multiple p-p collisions per bunch crossing (pile-up). In order to increase the use of tracks within the High Level Trigger (HLT), the ATLAS experiment planned the installation of an hardware processor dedicated to tracking: the Fast TracKer (FTK) processor. The FTK is designed to perform full scan track reconstruction at every Level-1 accept. To achieve this goal, the FTK uses a fully parallel architecture, with algorithms designed to exploit the computing power of custom VLSI chips, the Associative Memory, as well as modern FPGAs. The FT...

  18. Universality in fast quantum quenches

    CERN Document Server

    Das, Sumit R; Myers, Robert C

    2014-01-01

    We expand on the investigation of the universal scaling properties in the early time behaviour of fast but smooth quantum quenches in a general $d$-dimensional conformal field theory deformed by a relevant operator of dimension $\\Delta$ with a time-dependent coupling. The quench consists of changing the coupling from an initial constant value $\\lambda_1$ by an amount of the order of $\\delta \\lambda$ to some other final value $\\lambda_2$, over a time scale $\\delta t$. In the fast quench limit where $\\delta t$ is smaller than all other length scales in the problem, $ \\delta t \\ll \\lambda_1^{1/(\\Delta-d)}, \\lambda_2^{1/(\\Delta-d)}, \\delta \\lambda^{1/(\\Delta-d)}$, the energy (density) injected into the system scales as $\\delta{\\cal E} \\sim (\\delta \\lambda)^2 (\\delta t)^{d-2\\Delta}$. Similarly, the change in the expectation value of the quenched operator at times earlier than the endpoint of the quench scales as $\\langle {\\cal O}_\\Delta\\rangle \\sim \\delta \\lambda\\, (\\delta t)^{d-2\\Delta}$, with further logarithmic...

  19. Calculation technique for special tank capacity based on setting-out

    Science.gov (United States)

    Fan, Bai-xing; Li, Zong-chun; Li, Guang-yun; Sun, Qing-wen

    2008-12-01

    Special tanks are important for energy source storage and transport. Based on the research of current calculation techniques for special tank capacity, a new principle and technique for special tank capacity calculations is discussed, which converts the capacity calculation into setting out and sets up a tank coordinate system. It completes all the work with a surveying robot online control mode. The new technology can calculate the tank capacity fast and precise and avoids the disadvantage of traditional measurement technology. Furthermore, special a software system is compiled, which can measure, calculate, adjust and create report tables automatically. Finally, the measurement accuracy and efficiency of the measured data are analyzed.

  20. Does neighborhood fast-food outlet exposure amplify inequalities in diet and obesity? A cross-sectional study.

    Science.gov (United States)

    Burgoine, Thomas; Forouhi, Nita G; Griffin, Simon J; Brage, Søren; Wareham, Nicholas J; Monsivais, Pablo

    2016-06-01

    Greater exposures to fast-food outlets and lower levels of education are independently associated with less healthy diets and obesity. Little is known about the interplay between these environmental and individual factors. The purpose of this study was to test whether observed differences in fast-food consumption and obesity by fast-food outlet exposure are moderated by educational attainment. In a population-based cohort of 5958 adults aged 29-62 y in Cambridgeshire, United Kingdom, we used educational attainment-stratified regression models to estimate the food-frequency questionnaire-derived consumption of energy-dense "fast foods" (g/d) typically sold in fast-food restaurants and measured body mass index (BMI; in kg/m(2)) across geographic information system-derived home and work fast-food exposure quartiles. We used logistic regression to estimate the odds of obesity (BMI ≥30) and calculated relative excess risk due to interaction (RERI) on an additive scale. Participant data were collected during 2005-2013 and analyzed in 2015. Greater fast-food consumption, BMI, and odds of obesity were associated with greater fast-food outlet exposure and a lower educational level. Fast-food consumption and BMI were significantly different across education groups at all levels of fast-food outlet exposure (P < 0.05). High fast-food outlet exposure amplified differences in fast-food consumption across levels of education. The relation between fast-food outlet exposure and obesity was only significant among those who were least educated (OR: 2.05; 95% CI: 1.08, 3.87; RERI = 0.88), which suggested a positive additive interaction between education and fast-food outlet exposure. These findings suggest that efforts to improve diets and health through neighborhood-level fast-food outlet regulation might be effective across socioeconomic groups and may serve to reduce observed socioeconomic inequalities in diet and obesity.

  1. Fast box-counting algorithm on GPU.

    Science.gov (United States)

    Jiménez, J; Ruiz de Miras, J

    2012-12-01

    The box-counting algorithm is one of the most widely used methods for calculating the fractal dimension (FD). The FD has many image analysis applications in the biomedical field, where it has been used extensively to characterize a wide range of medical signals. However, computing the FD for large images, especially in 3D, is a time consuming process. In this paper we present a fast parallel version of the box-counting algorithm, which has been coded in CUDA for execution on the Graphic Processing Unit (GPU). The optimized GPU implementation achieved an average speedup of 28 times (28×) compared to a mono-threaded CPU implementation, and an average speedup of 7 times (7×) compared to a multi-threaded CPU implementation. The performance of our improved box-counting algorithm has been tested with 3D models with different complexity, features and sizes. The validity and accuracy of the algorithm has been confirmed using models with well-known FD values. As a case study, a 3D FD analysis of several brain tissues has been performed using our GPU box-counting algorithm.

  2. Production of selected cosmogenic radionuclides by muons; 1, Fast muons

    CERN Document Server

    Heisinger, B; Jull, A J T; Kubik, P W; Ivy-Ochs, S; Neumaier, S; Knie, K; Lazarev, V A; Nolte, E

    2002-01-01

    To investigate muon-induced nuclear reactions leading to the production of radionuclides, targets made of C/sub 9/H/sub 12/, SiO /sub 2/, Al/sub 2/O/sub 3/, Al, S, CaCO/sub 3/, Fe, Ni, Cu, Gd, Yb and Tl were irradiated with 100 and 190 GeV muons in the NA54 experimental setup at CERN. The radionuclide concentrations were measured with accelerator mass spectrometry and gamma -spectroscopy. Results are presented for the corresponding partial formation cross- sections. Several of the long-lived and short-lived radionuclides studied are also produced by fast cosmic ray muons in the atmosphere and at depths underground. Because of their importance to Earth sciences investigations, calculations of the depth dependence of production rates by fast cosmic ray muons have been made. (48 refs).

  3. Fast and Robust Stereo Vision Algorithm for Obstacle Detection

    Institute of Scientific and Technical Information of China (English)

    Yi-peng Zhou

    2008-01-01

    Binocular computer vision is based on bionics, after the calibration through the camera head by double-exposure image synchronization, access to the calculation of two-dimensional image pixels of the three-dimensional depth information. In this paper, a fast and robust stereo vision algorithm is described to perform in-vehicle obstacles detection and characterization. The stereo algorithm which provides a suitable representation of the geometric content of the road scene is described, and an in-vehicle embedded system is presented. We present the way in which the algorithm is used, and then report experiments on real situations which show that our solution is accurate, reliable and efficient. In particular, both processes are fast, generic,robust to noise and bad conditions, and work even with partial occlusion.

  4. Fast electron scattering as a tool to study target structure

    CERN Document Server

    Amusia, M Ya

    2006-01-01

    We concentrate on several relatively new aspects of the study of fast electron scattering by atoms and atom-like objects, namely endohedral atoms and fullerenes. We show that the corresponding cross sections, being expressed via so-called Generalized Oscillator Strengths (GOS), give information on the electronic structure of the target and on the role of electron correlations in it. We consider what sort of information became available when analyzing the dependence of GOS upon their multipolarity, transferred momentum and energy. We demonstrate the role of nondipole corrections in the small-angle fast-electron inelastic scattering. There dipole contribution dominates while non-dipole corrections can be considerably and controllably enhanced as compared to the case of low and medium energy photoionization. We show also that analyses of GOS for discrete level excitations permit to clarify their multipolarity. The results of calculations of Compton excitation and ionization cross-sections for noble gas atoms are...

  5. Fast Prediction Method for Steady-State Heat Convection

    KAUST Repository

    Wáng, Yì

    2012-03-14

    A reduced model by proper orthogonal decomposition (POD) and Galerkin projection methods for steady-state heat convection is established on a nonuniform grid. It was verified by thousands of examples that the results are in good agreement with the results obtained from the finite volume method. This model can also predict the cases where model parameters far exceed the sample scope. Moreover, the calculation time needed by the model is much shorter than that needed for the finite volume method. Thus, the nonuniform POD-Galerkin projection method exhibits high accuracy, good suitability, and fast computation. It has universal significance for accurate and fast prediction. Also, the methodology can be applied to more complex modeling in chemical engineering and technology, such as reaction and turbulence. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Model instruments of effective segmentation of the fast food market

    Directory of Open Access Journals (Sweden)

    Mityaeva Tetyana L.

    2013-03-01

    Full Text Available The article presents results of optimisation step-type calculations of economic effectiveness of promotion of fast food with consideration of key parameters of assessment of efficiency of the marketing strategy of segmentation. The article justifies development of a mathematical model on the bases of 3D-presentations and three-dimensional system of management variables. The modern applied mathematical packages allow formation not only of one-dimensional and two-dimensional arrays and analyse links of variables, but also of three-dimensional, besides, the more links and parameters are taken into account, the more adequate and adaptive are results of modelling and, as a result, more informative and strategically valuable. The article shows modelling possibilities that allow taking into account strategies and reactions on formation of the marketing strategy under conditions of entering the fast food market segments.

  7. Fast Digital Trigger Systems For Experiments In High- Energy Physics

    CERN Document Server

    Marciniewski, P J

    2001-01-01

    The data acquisition in high energy physics experiments is typically started by a pulse from a fast coincidence- based trigger system. It is essential that such a system can identify an event in a shortest possible time and with as good selectivity as possible. In order to meet these requirements, several new techniques and developments in the domain of signal discrimination and rapid hittopology analysis are presented. Two digital rise-time compensation methods were developed to improve the time resolution of the comparatively slow signals from inorganic scintillators. Both methods utilize double threshold analog comparators and digital processing logic. A unique adaptive threshold discrimination method was developed to reject after-pulses. The method was found to give the best timing, the smallest dead time and a complete rejection of noise pulses without missing physically significant pulses. Algorithms for fast multiplicity calculations of clusters of hits in two- dimensional matrices, in strings and in p...

  8. Fast image retargeting based on strip dividing and resizing

    Institute of Scientific and Technical Information of China (English)

    Shungang Hua; Honglei Wei; Tieming Su

    2014-01-01

    Based on image strip dividing, an effective and fast image retargeting algorithm is proposed for resizing images. First, we construct the image energy map using gradient magnitude of the pixels and calculate the accumulated energy of each column, dividing the image into several strips by integrating similar energy columns. The reduced amount of dimension is decided in inverse proportion to the average energy for each strip. Then we retar-get the image combining scaling with cropping in terms of each strip’s reduced ratio. Experiment results show that the proposed algorithm is capable of implementing fast image retargeting and preserving both the local structures and the global visual effect of the image.

  9. Solution space reduction in the peripheral nerve source localization problem using forward field similarities

    Science.gov (United States)

    Zariffa, José; Popovic, Milos R.

    2008-06-01

    Improving our ability to localize bioelectric sources within a peripheral nerve would help us to monitor the control signals flowing to and from any limb or organ. This technology would provide a useful neuroscience tool, and could perhaps be incorporated into a neuroprosthesis interface. We propose to use measurements from a multi-contact nerve cuff to solve an inverse problem of bioelectric source localization within the peripheral nerve. Before the inverse problem can be addressed, the forward problem is solved using finite element modeling. A fine mesh improves the accuracy of the forward problem solution, but increases the number of variables to be solved for in the inverse problem. To alleviate this problem, variables corresponding to mesh elements that are not distinguishable by the measurement setup are grouped together, thus reducing the dimension of the inverse problem without impacting on the forward problem accuracy. A quantitative criterion for element distinguishability is derived using the columns of the leadfield matrix and information about the uncertainty in the measurements. Our results indicate that the number of variables in the inverse problem can be reduced by more than half using the proposed method, without having a detrimental impact on the quality of the localization.

  10. CORTIM Project: Medical Regulation Concept Designed for Forward Field Casualty Management Based on an Information System

    Science.gov (United States)

    2010-04-01

    CORTIM, and the quality of casualty handling by the SAMU (the French Mobile Emergency Medical Service) for the RMT concept. We consider that...of crisis situations in the case of CORTIM, and the quality of casualty handling by the SAMU (the French Mobile Emergency Medical Service) for the... SAMU for the RMT concept. We consider that operational casualty management can be enhanced in at least three areas. The first concerns improvements in

  11. Calculation of Spectra of Solids:

    DEFF Research Database (Denmark)

    Lindgård, Per-Anker

    1975-01-01

    The Gilat-Raubenheimer method simplified to tetrahedron division is used to calculate the real and imaginary part of the dynamical response function for electrons. A frequency expansion for the real part is discussed. The Lindhard function is calculated as a test for numerical accuracy. The condu...

  12. Calculator. Owning a Small Business.

    Science.gov (United States)

    Parma City School District, OH.

    Seven activities are presented in this student workbook designed for an exploration of small business ownership and the use of the calculator in this career. Included are simulated situations in which students must use a calculator to compute property taxes; estimate payroll taxes and franchise taxes; compute pricing, approximate salaries,…

  13. Calculating charged defects using CRYSTAL

    Science.gov (United States)

    Bailey, Christine L.; Liborio, Leandro; Mallia, Giuseppe; Tomić, Stanko; Harrison, Nicholas M.

    2010-07-01

    The methodology for the calculation of charged defects using the CRYSTAL program is discussed. Two example calculations are used to illustrate the methodology: He+ ions in a vacuum and two intrinsic charged defects, Cu vacancies and Ga substitution for Cu, in the chalcopyrite CuGaS2.

  14. Economic calculation in socialist countries

    NARCIS (Netherlands)

    Ellman, M.; Durlauf, S.N.; Blume, L.E.

    2008-01-01

    In the 1930s, when the classical socialist system emerged, economic decisions were based not on detailed and precise economic methods of calculation but on rough and ready political methods. An important method of economic calculation - particularly in the post-Stalin period - was that of

  15. Neural network model for the efficient calculation of Green's functions in layered media

    CERN Document Server

    Soliman, E A; El-Gamal, M A; 10.1002/mmce.10066

    2003-01-01

    In this paper, neural networks are employed for fast and efficient calculation of Green's functions in a layered medium. Radial basis function networks (RBFNs) are effectively trained to estimate the coefficients and the exponents that represent a Green's function in the discrete complex image method (DCIM). Results show very good agreement with the DCIM, and the trained RBFNs are very fast compared with the corresponding DCIM. (23 refs).

  16. An Efficient Way of Calculating Rotated Template Set Operators for Parallel Image Processing

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper presents a novel method of calculating the rotated template set operators. Having defined a rotated ring model, the author proposes an efficient way of executing the rotated template set operators, which uses the rotated ring model and a fast cyclic convolution algorithm from the Number Theoretic Transform. The author showns that a class of rotated templates can be modelled as rotated rings and computed efficiently by the fast algorithm with much fewer multiplies than the normal approach in the worse cases.

  17. Closure and Sealing Design Calculation

    Energy Technology Data Exchange (ETDEWEB)

    T. Lahnalampi; J. Case

    2005-08-26

    The purpose of the ''Closure and Sealing Design Calculation'' is to illustrate closure and sealing methods for sealing shafts, ramps, and identify boreholes that require sealing in order to limit the potential of water infiltration. In addition, this calculation will provide a description of the magma that can reduce the consequences of an igneous event intersecting the repository. This calculation will also include a listing of the project requirements related to closure and sealing. The scope of this calculation is to: summarize applicable project requirements and codes relating to backfilling nonemplacement openings, removal of uncommitted materials from the subsurface, installation of drip shields, and erecting monuments; compile an inventory of boreholes that are found in the area of the subsurface repository; describe the magma bulkhead feature and location; and include figures for the proposed shaft and ramp seals. The objective of this calculation is to: categorize the boreholes for sealing by depth and proximity to the subsurface repository; develop drawing figures which show the location and geometry for the magma bulkhead; include the shaft seal figures and a proposed construction sequence; and include the ramp seal figure and a proposed construction sequence. The intent of this closure and sealing calculation is to support the License Application by providing a description of the closure and sealing methods for the Safety Analysis Report. The closure and sealing calculation will also provide input for Post Closure Activities by describing the location of the magma bulkhead. This calculation is limited to describing the final configuration of the sealing and backfill systems for the underground area. The methods and procedures used to place the backfill and remove uncommitted materials (such as concrete) from the repository and detailed design of the magma bulkhead will be the subject of separate analyses or calculations. Post

  18. Calibration techniques for fast-ion D{sub {alpha}} diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Heidbrink, W. W.; Bortolon, A.; Muscatello, C. M.; Ruskov, E. [University of California, Irvine, California 92697 (United States); Grierson, B. A.; Podesta, M. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2012-10-15

    Fast-ion D{sub {alpha}} measurements are an application of visible charge-exchange recombination (CER) spectroscopy that provide information about the energetic ion population. Like other CER diagnostics, the standard intensity calibration is obtained with an integrating sphere during a vacuum vessel opening. An alternative approach is to create plasmas where the fast-ion population is known, then calculate the expected signals with a synthetic diagnostic code. The two methods sometimes agree well but are discrepant in other cases. Different background subtraction techniques and simultaneous measurements of visible bremsstrahlung and of beam emission provide useful checks on the calibrations and calculations.

  19. Parallel AFMPB solver with automatic surface meshing for calculation of molecular solvation free energy

    Science.gov (United States)

    Zhang, Bo; Peng, Bo; Huang, Jingfang; Pitsianis, Nikos P.; Sun, Xiaobai; Lu, Benzhuo

    2015-05-01

    We present PAFMPB, an updated and parallel version of the AFMPB software package for fast calculation of molecular solvation-free energy. The new version has the following new features: (1) The adaptive fast multipole method and the boundary element methods are parallelized; (2) A tool is embedded for automatic molecular VDW/SAS surface mesh generation, leaving the requirement for a mesh file at input optional; (3) The package provides fast calculation of the total solvation-free energy, including the PB electrostatic and nonpolar interaction contributions. PAFMPB is implemented in C and Fortran programming languages, with the Cilk Plus extension to harness the computing power of both multicore and vector processing. Computational experiments demonstrate the successful application of PAFMPB to the calculation of the PB potential on a dengue virus system with more than one million atoms and a mesh with approximately 20 million triangles.

  20. Fast Steerable Principal Component Analysis.

    Science.gov (United States)

    Zhao, Zhizhen; Shkolnisky, Yoel; Singer, Amit

    2016-03-01

    Cryo-electron microscopy nowadays often requires the analysis of hundreds of thousands of 2-D images as large as a few hundred pixels in each direction. Here, we introduce an algorithm that efficiently and accurately performs principal component analysis (PCA) for a large set of 2-D images, and, for each image, the set of its uniform rotations in the plane and their reflections. For a dataset consisting of n images of size L × L pixels, the computational complexity of our algorithm is O(nL(3) + L(4)), while existing algorithms take O(nL(4)). The new algorithm computes the expansion coefficients of the images in a Fourier-Bessel basis efficiently using the nonuniform fast Fourier transform. We compare the accuracy and efficiency of the new algorithm with traditional PCA and existing algorithms for steerable PCA.