The applicability of boundary element method has been shown by its applications to scalar potential problems. However, unified formulations for the boundary element method using vector variables and relations between unknown vector variables and the accuracy of the solutions have not been discussed. In this paper, the unified formulation, how to select unknowns and their influence to the accuracy of the solutions in magnetostatics and electrostatics were investigated, and the following results were obtained.
When electric field is assumed as unknown in electrostatic problems, or magnetic flux density or vector potential is assumed as unknown in magnetostatic problems, the formulation for the boundary element method using vector variables can be performed. In magnetostatic problems, the equations for the method using a vector potential were shown, and their suitability was verified. Furthermore, in the method using the vector potential as unknown, there is a tendency for computational error of magnetic flux density to larger than the method using magnetic flux density as unknown, and computational error for the numerical integration of magnetic flux density may become large near the boundary surfaces because of its strong singularity.

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In order to improve natures of polyethylene, they use to combine with halogen atoms or add halogenides to it. One of them is chlorinated polyethylene, which was reported to have better resistance against electrical tracking and discharge.
In this paper, surface chlorinated polyethylene films were made from a marketing low density polyethylene film by ultraviolet rays shinning in Cl₂ gas. Then, we studied detailed properties of the films and the oxidation weight increase grown by partial discharges.
The following results were obtained: The chlorination weight increase is larger than the value (about 12%wt) reported already. The chlorination and the cross linkage of polyethylene films grow at the same time. And then, the oxidation weight increase which comes from partial discharges, becomes smaller as the chlorination increases. And as the discharge time becomes longer, it increases because the sample surface is eroded by the discharge energy.
These results are known by measurments of dimension and weight, wearing tests, infrared absorption method, dynamic viscoelasticity tests, and so on.

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The authors have studied the electrical discharge in the left-hand side region of the pdmin. which gives the minimum breakdown voltage on Paschen's curve. To know the selfsustaining mechanism in this region, the light intensity distribution was measured. The light intensity from the higher excitation energy level was stronger than that of lower one in the whole discharge area. So, it is confirmed experimentally that higher energy electrons were generated under this discharge condition than in the ordinary glow discharge.
Next, the electron motion in this pd region was simulated by the Monte Carlo method. In the simulated energy distribution, there were two groups of electron swarms. One is beam like one and the other is low energy group. Especially, at the position closer to the anode, the existence ratio of lower energy electron was large. It is concluded that the reflected electrons at the anode are effective for the electron multiplication and the discharge sustaining.

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Aiming at the low temperature fabrication process for polycrystalline silicon films, we employed L-coupled plasma CVD method with and without mesh electrode.
Silane diluted with hydrogen, as a gas source, was introduced into a quartz tube and decomposed by rf power inductively applied. Polycrystalline silicon films were formed on the substrates such as glass and quartz.
The strong preferred orientations in the films were observed at the substrate temperature of above 550°C. Small amount of boron not only increased the crystal growth, but also was effective for reducing the growth temperature.
A pressure sensor using the polycrystalline silicon films doped with boron was fabricated and estimated in the application points of view.

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Neural mechanism of the retina may perform the principal role of luminosity transformation. In this paper, non-linearity of the Munsell value function was discussed on the physiological basis. Amplitude response function of the retinal neurons is approximated as a sigmoidal one V=V_max•X/(X+S). This function may more essentially express the visual process, because it could be shown that this function includes parts well fitting to the well known psychological response functions, Weber-Fechner and Steven's law.
Introducing an idea of neural adaptation to this function, the Munsell value function can be more precisely approximated. The conclusive equations were expressed as V=V_max•X/{X+S(X)} and S(X)=X₀{1+5.55•X/(X+1.8•X₀)}, where X₀ was background light intensity or refrectance, and X was test light one. This equation means that the adaptation level S(X) varied with two components, groval intensity (X₀) and local one (X).

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Self-Shielded axial gradient coils for eddy-current-free NMR imaging and spectroscopy have been designed using the target field approach proposed by Turner, Mansfield and Chapman. Optimal radius for the target field was determined to eliminate the additional resistors which may degrade the transient shielding performance. The magneic fields generated by the designed coils were calculated using Fourier-Bessel expansion, showing that the coils produce highly linear gradients and very small residual external fields.

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