The phenomena in the electromagnetic field intrinsically spread over the infinite space. The purpose of this paper is to provide a useful method for numerical calculation of the electromagnetic field with open boundary.
The finite element method (FEM) and the boundary element method (BEM), which have entirely different features from each other, are useful for numerical analysis. This paper describes the hybrid finite element and boundary element method for the three-dimensional eddy current problems with open boundary. In the hybrid method, we adopt the magnetic field intensity H and the magnetic scalar Potential ψ as the physical quantities.
The conductive region is analyzed by the FEM adopting H and ψ, on the other hand, the free space having a supply current in it by a novel BE formlation using ψ. Even in a region with a snpply current, we can define the scalar potential ψ by regarding a closed current as a magnetized shell, which makes it possible to calculate ψ analytically. In this paper we adopt the scalar potential as much as possible in the hybrid method for decreasing the number of unkown variables.
Several practical applications of the proposed method to the three-dimensional eddy current problems are presented.

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We have measured the dependence of the probe characteristics in an Ar plasma on a-Si: H film thickness. The plasma is produced in a chamber of double tubed coaxial line type microwave plasma chemical vapor deposition system. It has been cleared that the ordinary probe characteristics are obtained when the film thickness is less than 40nm. It has also been cleared that a 300nm thick film of a-Si: H deposited on the probe surface can be removed by ion bombardment for 20s in the Ar plasma (electron temperature: Te_??_42, 000K, electron density: ne_??_3.7×10¹⁰cm^-3) when the bias voltage of -200V is applied to the probe. Using this probe measurement technique, we have measured the spatial distribution of plasma parameters Te, ne in the Ar plasma and the Ar-SiH₄ plasma and discussed the difference between these two plasmas.

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A low-inductance, multichannel railgap has been used to switch a low-inductance capacitor bank driving, for example, a dense plasma focus. To generate multichannel arcs, a fast rising trigger voltage, greater than 5kV/ns, is necessary (Neil's condition).
In order to obtain a high-voltage and short rise time pulse, a sharpener is indispensable. A self-breakdown gap is generally used for this, but it is not reliable. We therefore investigated the charactaristics of a ferrite sharpener, which is much more reliable. We achieved the following results.
(1) We obtained detailed data on relation of output rise time to source voltage, bias current, and line length. (2) We found that the ferrite sharpener is superior to the sharpener gap in reliability of operation. (3) At a source voltage of 14kV, the rise time of the ferrite sharpener attained the speed of 5kV/ns.

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In order to know the effect of crystallinity on electrical conductivity of α Cu-Phthalocyanine (CuPc), the thin films were formed on the glass substrate cleaned with ethyl alcohol in the ultrasonic washer, by means of the vacuum evaporation method. The crystallinity of the thin film was modified by the variation of the substrate temperature. The substrate temperature was changed over a range from -160 to 40°C by heating it with a electric heater and cooling it with the liquid nitrogen. As a results, α CuPc thin films were obtained in the range of the degree of crystallinity from 15 to 60%. The crystallinity of CuPc decreased with decreasing the substrate temperature. Electrical conduction was measured at room temperature in a vacuum vessel by applying the dc voltage. The electrical resistivity in the parallel direction to the substrate, decreased gradually and that in the vertical direction to the substrate, increased gradually with decreasing the degree of crystallinity. It would be surmised that these results is due to a variation of the mobility of, π-electron as a charge carrier in α CuPc.

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Luminescence phenomenon from high- Tc oxide superconductors (HTSC's) is peculiar to this materials, not to metal-superconductors. Because of the sensitivity to crystalline defects (stoichiometory, impurities, an oxygen vacancies), luminescence measurement is expected to be effective for characterization method for HTSC's. In this study, cathodeluminescence (CL) is proposed, the relations of superconductivity with CL have been investigated as a function of the amount of impurities (raw materials, intermediate products) and oxygen contents in Y-Ba-Cu-O (YBCO) system HTSC's. Characteristic CL have been successfully observed in the YBCO samples controlled the amount of impurites. As the amount of impurities increased, the luminous areas increased and critical temperature Tc fell down. Electron probe micro analizer clarified that CL in visible region was attributed to the impurity phases in YBCO samples. Moreover, the luminescence spectra in the luminous areas were idetified with the spectra which were obtained from the impurities itself. From thses results, cathodeluminescence is the very useful method to obtain the informations about the impurities in HTSC's.

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Flux control characteristic is one of the important basic characteristics of the Ferrite Orthogonal Core (FOC) when it is used as a measuring-control element. Up to this date, some analysis on flux control characteristic of FOC were reported. However, the circuit conditions of the control side of FOC were not sufficiently considered. Hence, these analysis are not satisfactory used for designing FOC as a measuring-control element. In this paper, a new analysis method for flux control characteristic of FOC is reported. A new method can be widely applied to control circuit of FOC under constrained or free magnetization condition.

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In order to take full advantage of combined effects of metal and plastic materials, we have developed a composite tape combining lead foil which lacks mechanical strength with plastic film which imparts strength. This composite tape is designed to serve the purpose of a water-impervious layer in an XLPE cable. Evaluation of its properties such as corrosion resistance, fatigue, expansion and shrinkage was made. The results of tests indicate that the combination of lead foil with plastic film is more effective in several ways than either alone. As one of its applications, the lead laminate tape was used as water impervious layer in an XLPE cable. This composite materials may be used not only in XLPE cable applications but also in many other various fields of industry.

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The surface discharge on dielectric surfaces of a spacecraft caused by spacecraft charging is simulated by using a high vacuum chamber equipped with an electron beam gun. Fluoroethylenepropylene (FEP) and polyethyleneterephthalate (PET) films frequently employed as thermal control materials are irradiated by an electron beam until surface discharges occur, then the spectrum and waveform of emitted light of discharge, together with the current waveform of the discharge and the mass spectrum of the gas in the vacuum chamber are measured.
In the range of 300 through 700nm of the wavelength, light emission from CN radicals, C₂ radicals, CH radicals and hydrogen atoms are detected. From this result, it is suggested that water molecules in the residual gas and molecules in the structure of the specimen contribute the light emission. The spectroscopic observation of the light emission suggests that the discharge energy is concentrated on PET more than that on FEP.

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