Implementation of prime decomposition of polynomial ideals over small finite fields

AbstractAn algorithm for the prime decomposition of polynomial ideals over small finite fields is proposed and implemented on the basis of previous work of the second author. To achieve better performance, several improvements are added to the existing algorithm, with strategies for computational flow proposed, based on experimental results. The practicality of the algorithm is examined by testing the implementation experimentally, which also reveals information about the quality of the implementation

Implementation of prime decomposition of polynomial ideals over small finite fields

AbstractAn algorithm for the prime decomposition of polynomial ideals over small finite fields is proposed and implemented on the basis of previous work of the second author. To achieve better performance, several improvements are added to the existing algorithm, with strategies for computational flow proposed, based on experimental results. The practicality of the algorithm is examined by testing the implementation experimentally, which also reveals information about the quality of the implementation

Statistical induction of a thermal transport model based on the transport analyses database

A new approach for inducing a thermal transport model, of ion heat diffusivity as an example, for magnetically confined high-temperature plasmas has been further pursued after its initial proposal by Yokoyama (2014 Plasma Fusion Res. 9 1302137). It has been based on a statistical approach utilizing the accumulated experimental transport analyses database. Two approaches are described in this paper: (1) placing a priority on reproducing the ion heat diffusivity with higher accuracy for better reproduction of ion temperature profiles, and (2) attempting to acquire a physics interpretation through variable selections and the dependence of the ion heat diffusivity on them. Such progress will foster the study of a practical transport model for real-time control and the provision for guidance to the parameter dependence to be pursued by large-scale cutting-edge simulations

最適化されたヘリカル軸ステラレータの研究

本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものである京都大学0048新制・課程博士博士(工学)甲第6546号工博第1556号新制||工||1045(附属図書館)UT51-96-T492京都大学大学院工学研究科原子核工学専攻(主査)教授 若谷 誠宏, 教授 木村 逸郎, 教授 東 邦夫学位規則第4条第1項該当Doctor of EngineeringKyoto UniversityDFA

Electron Temperature Measurement by Thomson Scattering in Tokamak NOVA II

The Thomson scattering method was applied to determine the temperature and density profiles of plasma electrons in the NOVA II tokamak. To minimize the intensity of stray light, use was made of a viewing damp, which was an array of blue-glass knife edges. The radial profile of electron density has been found to be approximately parabolic, while the temperature profile appeared more peaky and can be represented by the square of the parabolic expression. The electron energy confinement time determined by this method is in good agreement with that predicted by the Alcator scaling law

Torsional Response Induced by Lateral Displacement and Inertial Force

Eccentric distribution of stiffness, damping, and mass of a structure, and spatially non-uniform ground motion input to a long or large base mat of a structure are well-known causes of torsional response. We have discovered that the torque generated by horizontal displacement and perpendicular inertial force, which we call the Q-Δ effect, can be a cause of torsional response. We formulated the equation of motion of a single finite-size mass-linear elastic shear and torsion spring model and clarified the resonance condition of the torsional response to sinusoidal ground acceleration. Time-history response analysis verified that the torsional response forms beat and the maximum torsional response of the simulation result agrees with that theoretically predicted. Further time-history response analysis conducted of white noise ground acceleration showed that even one-directional white noise ground acceleration can induce torsional response in a linear elastic system without any structural eccentricity

Progress of statistical modelling of thermal transport of fusion plasmas

Progress of statistical modelling of thermal transport of fusion plasmas based on (2–4 a) a transport analysis database is described. Statistically induced ion and electron thermal diffusivities are checked with an actual discharge which had not been included in the database. Usefulness of this statistical approach is explained in terms of (1) extracting important parameters through the application of information criterion, and (2) making possible for discussing exponents of regression expression and then implying the thermal transport property. The statistical approach reported in this paper could provide a new insight for thermal transport modelling for fusion plasmas, complementing conventional global scalings on the energy confinement time