A self-consistent modelling and simulation technique of rf non-equilibrium plasmas using a Monte Carlo method is presented. In the model, the kinetics of electrons and ions is calculated by a Monte Carlo method which enables us to incorporate the non-equilibrium effect of electron energy distribution against the electric field. This effect may be important under the condition that the product of the gas pressure and the gap length is small and/or the electric field changes rapidly, as commonly seen with rf non-equilibrium plasmas. The electric field in plasma is self-consistently determined by solving Poisson's equation. The technique is applied torf plasmas in Ar gas and the results suggest that the present model can adequately simulate rf plasmas.

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In order to attain lower voltage operation of the glow-discharge devices such as a plasma display panel, the author intended to utilize the alkaline metals as the cathode material and made experimental and theoretical investigations of mainly normal cathode fall voltage V_n. First, in the experimental tubes of simple structure Cs, Rb, K, Na, and Li were introduced by vapor phase deposition and the cold-cathode voltage-current characteristics were measured for various noble gases leading to obtain the values of V_n. As a result it was revealed that V_n in these cathodes were lower by about half than that in the conventionaly used Ni cathode. Second, in order to get a guide to search cathode materials, Hagstrum's theory of ionic secondary electron emission coefficient γ_i in the metal was arranged and applied to various combinations of work function, Fermi energy of cathode materials, and ionization energy of the discharge gases resulting in the derivation of comparatively simple expressions and calculations of the γ_i. Moreover, by combining these results with the Ward's theory of cathode fall, theoretical values of V_n was obtained and compared with the above mentioned experimental values.

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Effect of discharge inception voltage on electromagnetic noise spectra in VHF and UHF region from spark discharge at hemisphere-plane electrodes in atmosphere is studied. The discharge inception voltages are changed by several means, such as increasing gap length from 2mm to 6mm, or UV-ray irradiation, or increasing stress concentration at the electrode tip, or spreading dust such as cotton cloths, acylic resin particles, copper particles, or alminum particles on the plane electrode.
When the discharge inception voltage is increased, macroscopic slope of noise spectra from 100MHz to 1 GHz decreases generally, that is, high frequency components of noise increase with thevoltages.
These phenomena can be explaned by theoretical analysis based onToepler's Law of spakdischarge and Hertz's dipole EM radiation law. As the exceptional cases, low dicharge inception voltages by metal particles or by positive stress concentration at the electrode tip do not contribute much to suppression of high frequency components of the noise.

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It is well known that space charge accumulates in dielectrics under DC voltage application, and should be considered to develop polymer insulated DC cables. This paper shows the space charge distribution in a practical XLPE insulated cable observed by the pulsed electroacoustic method at room temperature, and the distribution changes with the period of DC voltage application. Hetero-charge ditribution was obtained immediately after the voltage application, so that the subsequent behavior of the space charge is influenced by the additional electric field generated by the accumulated hetero charge. Electron injection conpensates the hetero positive charge near the negative electrode, resulting in the modelation of the electric field intensity at the interface between the insulation and the conductor. Based on the experimental results, space charge conformation model is proposed, and the relationship between the space charge accumulation phenomena and the DC breakdown characteristics is considered.

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It has been indicated that an estimate S of the standard deviation S obtained by the up-and-down method has some bias and the method for determining the confidence interval of S through the Fisher's amount of information is inaccurate. This paper shows that the bias of S can be corrected by using the bias corrected bootstrap method and that an accurate confidence interval of S can be obtained. For easy understanding, a detail explanation of the method for determining the confidence interval is shown in this paper by a concrete example of the up-and-down method. This is an introduction for the practitioners. This method was proved correct by the Monte Carlo simulation.
The up-and-down method is still popular as a testing method for determining the impulsebreakdown voltage. This method is particularly effective when the estimate of the standard deviation S of the breakdown voltage is larger than the up-and-down voltage distance d (i. e, when d/S is small).

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Langmuir-Blodgett (LB) heterofilms consisting of the polar and nonpolar LB films are prepared and resistivity of the heterofilms is investigated. Sample structure is Al/polar LB film/nonpolar LB film/Au (polar/nonpolar) or Al/nonpolar LB film/polar LB film/Au (nonpolar/polar). Arachidic acid LB film (Y type) is used as the nonpolar LB film, and 2-pentadecy 1-7, 7', 8, 8' -tetracyano-quinodimethane, protoporphirin dimethyl ester, mesoporphyrin dimethyl ester and polyamic acid alkylamine salts LB films (Z type) are utilized as the polar LB film. According to the experimental results, the LB heterofilm of nonpolar/polar has the electrical conductivity higher than the metal conductivity. On the other hand, the heterofilm of polar/nonpolar is insulator. It is expected that such conducting and insulating properties of LB heterofilm would be applied to the molecular electronics which is a new technology in the future.

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The treeing resistance of low density polyethylene is drastically improved in oxygen free condition such as in vacuum or at 77 K.
In oxygen free condition, the deteriorated region is formed in high field region before tree initiation. The chemical analysis of the deteriorated region by FT-IR and Raman spectroscopy showed that it has excess carbonyl groups (C=O) and double bonds (C=C) than normal polyethylene, and that the amorphous part increases in it.
In the deteriorated region, a number of voids and cracks were observed by scanning electron microscope (SEM). Their size is less than 0.5μm diameter. The observation by transmission electron microscope (TEM) revealed that the lamella of polyethylene tends to disappear in the deteriorated region. These results suggest that chains of polyethylene are scissored in the deteriorated region during high electric field application.

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This paper describes the influences of a surfactant on XLPE insulation. Several kinds of additives are mixed into the insulation in order to improve the dielectric breakdown strength of XLPE cables. It has been verified that the "Interfacial Diffusion Method", which modifies the interfacial region between the insulation and the semiconducting layer by a surfactant, is effective. The effects of the surfactant on the morphology in the XLPE insulation were studied with two kinds of specimens.
In the first kind of specimens, a mill was used to disperse the surfactant throughout the insulation material. A. C. dielectric breakdown tests were carried out on disk specimens. Their average breakdown strengths were improved but the breakdown strengths were not increased at the low probabilities of the hazard function. In the other specimens, the surfactant was milled into the semiconducting layer, and later allowed to enter the insulation by diffusion during the hightemperature crosslinking process. It was found that the average breakdown strengths were improved further and also the breakdown strengths were found to increase significantly at the lowprobabilities of the hazard function.
The two kinds of specimens were followed by material analysis using analytical methods, such as TEM, FT-IR, etc. Results from the milled specimen indicated that the improvement in property was probably due to the increase in density of the amorphous portion, the increase in the lamella thickness, and the increase in the spherulite radius brought about with the additive content. Therefore the insulation near the interface where a concentration gradient was established by diffusion from the semiconducting layer is considered to have similar morphological changes caused by the additive. In addition, the diffusion specimen was observed to have an absence of introduced microdefects which existed in the milled specimen.

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