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Various types of numerical analysis methods for electromagnetic problems have been established and finite element methods and integral equation methods are practically used in the design of electrical machines. On the other hand, the technology of personal computer hardware is rapidly progressing and practical electromagnetic computation can be performed by a personal computer. Recently high end machines are equipped with multi-CPU and multi-core. This means that parallel computation can be done by the personal computer without special hardware. In this paper, parallelization of the ICCG method is investigated. The ICCG method is a suitable solver for finite element methods using edge elements but parallelization of the method is difficult because of dependent data structure. Effective parallelization principles are described using some simple examples and effectiveness of the parallelized ICCG method is shown.

Magnetic field analysis of nondestructive testing using remanent magnetism was performed by using two-dimensional finite element method. A leakage flux method using remanent magnetism is applied to magnetic material as nondestructive testing method. The remanent magnetism is approximated by equivalent magnetizing electric current. And we assumed that the remanent magnetization is in proportion to the magnetization in the magnetizing process. Formulation of the finite element method using magnetization is described. A simple model was used to confirm the applicability of the leakage flux method using remanent magnetism. It became clear that small lift-off of probe was required to detect small defects because magnetic field induced by the remanent magnetism decreased rapidly with distance from the defect.

アンケート調査におけるペーパーレス化と効率的なデータ入力, 自動的な集計処理と迅速な結果の公開を目的として, WWWを利用したアンケート処理システムを開発した. 本システムは, 第87回薬剤師国家試験問題評価のアンケート処理システムとして開発したものである. 本論文では, システムの開発に必要なWWWの基本的な仕組みとWWWを利用したシステム固有のデータ処理や基本的なセキュリティ対策などについて報告する., In this paper, a WWW based questionnaire processing system is proposed in order to develop the paperless procedure in questionnaire surveys, the efficient data input and its prompt publication of the results. More concretely, we propose the questionnaire processing system for the purpose of evaluating the 87th pharmacist national examination question in Japan. That is, in this study, after describing the basic mechanism of WWW for developing the system, we propose its specific data processing method using WWW and the basic security measures.

Three-dimensional electromagnetic field analysis of pulsed eddy current testing by a finite element method is presented. Transient electromagnetic field analysis is performed by the Fourier transform method based on three-dimensional edge-element finite element analysis. The eddy current density and magnetic flux density distributions at each time step are obtained by the inverse Fourier transform using the computation results of frequency domain. The method was applied to the TEAM Workshop problem 27. The computation results provided good agreement with the experimental results.