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Miyato, Naoaki; Kishimoto, Yasuaki; Li, J.
Physics of Plasmas, 11(12), p.5557 - 5564, 2004/12
Times Cited Count：116 Percentile：94.97(Physics, Fluids & Plasmas)Global characteristics of the coupled system of zonal flows and electromagnetic ion temperature gradient driven turbulence in tokamak plasmas are investigated using a global electromagnetic Landau fluid code. Zonal flow behavior changes with the safety factor 
. In a low region stationary zonal flows are excited and suppress the turbulence effectively. Coupling between zonal flows and poloidally asymmetric pressure perturbations due to a geodesic curvature makes the zonal flows oscillatory in a high region. Energy transfer from the oscillatory zonal flows to the turbulence via the poloidally asymmetric pressure perturbations is identified. Therefore in the high region where the zonal flows are oscillatory, the zonal flows cannot quench the turbulence and turbulent transport is not suppressed completely. As for the zonal flow behavior, it is favorable for confinement improvement to make the low region where the stationary zonal flows are dominant in tokamak plasmas.
Sasa, Narimasa
Nihon Oyo Suri Gakkai Rombunshi, 14(2), p.91 - 98, 2004/06
Splitting scheme is applied to solve numerically the time dependent Ginzburg-Landau and Maxwell equations which describe superconducting state in materials. First and second order splitting schemes are constructed with spacial difference method by using the link variables. We perform various numerical experiments and compare numerical stability by changing order of the schemes.
Sasa, Narimasa; Machida, Masahiko; Yamada, Susumu; Arakawa, Chuichi
Keisan Kogaku Koenkai Rombunshu, 8(2), p.757 - 758, 2003/05
no abstracts in English
Sasa, Narimasa; Machida, Masahiko; Yamada, Susumu; Arakawa, Chuichi
Keisan Kogaku Koenkai Rombunshu, 7(1), p.171 - 172, 2002/05
Algebraic Multi Grid(AMG) is applied to solve the Ginzburg-Landau equations for Superconductors. The method effectively solves large scale linear algebraic equations. AMG is also applicable for systems with complex boundary condition in contrast with usual Geometrical Multi Grid.
Fujita, Ayumi
Physical Review B, 64(6), p.064504_1 - 064504_6, 2001/08
Times Cited Count：0 Percentile：0(Materials Science, Multidisciplinary)We study parametric level statistics of the discretized excitation spectra inside a moving vortex core in layered superconductors with impurities. The universal conductivity is evaluated numerically for the various values of rescaled vortex velocities 
from the clean case to the dirty limit case. The random matrix theoretical prediction is verified numerically in the large regime. On the contrary in the low velocity regime, we observe 
which is consistent with the theoretical result for the super-clean case, where the energy dissipation is due to the Landau-Zener transition which takes place at the points called ``avoided crossing''.
Iwase, Akihiro; Ishikawa, Norito; Iwata, Tadao*; Chimi, Yasuhiro; Nihira, Takeshi*
Physical Review B, 60(15), p.10811 - 10819, 1999/00
Times Cited Count：4 Percentile：28.64(Materials Science, Multidisciplinary)no abstracts in English
*; Kunugi, Tomoaki; Koga, J. K.
Computer Physics Communications, 108(2-3), p.159 - 179, 1998/00
Times Cited Count：14 Percentile：62.89(Computer Science, Interdisciplinary Applications)no abstracts in English
JAERI-M 5349, 72 Pages, 1973/07
no abstracts in English
Progress of Theoretical Physics, 50(4), p.1156 - 1181, 1973/04
Times Cited Count：37no abstracts in English
