This paper proposes a language, named Circuit Description Language (CDL), to describe the information of a circuit for computer-aided analysis and design. The syntax of CDL provides strong modularity which enables to build a circuit using previously defined other circuits (building-block construction of a circuit). This feature allows to build a library of standard power-system models. In this paper, example circuits are described using CDL in order to show the power of modularity.

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Small solid particles are usually used as tracers for the measurement of flow velocity of a fluid. In the case of high temperature thermal plasma, sometimes it is difficult to use solid tracers due to the loss by vaporization caused by strong heat transfer from the plasma. If the gaseous tracers could be used, it would compensate for the difficulty in using conventional solid particle tracers. To investigate the feasibility of gaseous tracers, hydrogen was used as a gaseous tracer for flow velocity measurement of wall stabilized argon arc plasma. Propagation of H α line emission along the arc axis was observed by high-speed photography using a CCD camera with band-pass filters. The propagation velocity was 30-100m/s which was influenced by flow rate of argon. The Peclet number was calculated for the experimental condition. The result shows that the effect of the diffusion on the mass transport is smaller than that of the flow. This means the propagating velocity of the H α line emission closely corresponds to the flow velocity of the argon arc plasma with the added hydrogen. The measured velocity and the estimated average flow velocity of argon arc plasma were in good agreement. The principle of the gaseous tracer was confirmed, however further work will be needed for practical use.

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A needle-plane electrode configuration containing insulating barriers with a narrow gap which is just below and along the needle on the plane has been consisted. Characteristics of the discharge which is a series of a gas gap discharge and a creeping one developed in the narrow gap of the barrier filled with SF₆ have been studied. In the case of gap width shorter than about 100μm, the flashover voltage increased with decreasing gap width by the suppression of the creeping corona extension. On the contrary, in the range of gap width longer than about 200μm, the flashover voltage increased with increasing gap width due to the increase of corona path. And it was found that the creeping corona path gradually decreased with increasing gap width.

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Temporal evolutions of electrons have been investigated on extinction process in radio frequency (RF) afterglow plasmas using various gases. The electron density was found to increase just after the RF power was switched off, and then decayed. This density growth depended on the gas pressure and gas mixture ratio, especially amount of Ar gas. The growth mechanism has been studied by considering collisions between the metastable atoms to account fully for the results.

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This paper proposes a new absolute displacement sensor which is long scale high resolution. This sensor consists of the transmission line where it is driven by a VCO as a scale and the probe as a measurement object. It is used that the position of 1/2λ from the terminal point becomes the node of standing wave at the transmission line where the terminal is short-circuited, and it obtains the displacement of the probe from the terminal point by controlling the frequency of the VCO so that the position of the probe may always become the node of standing wave.
In order to obtain high resolution in this sensor, it is necessary to detect the node precisely. This paper shows the way to detect the node by frequency modulating the VCO and synchronous detecting the signal picked out with the probe by using the modulation signal.
We experimentally confirmed that the proposed sensor has the resolution of 40μm in the displacement from 3.51m to 3.89m, and showed that the absolute displacement sensor which is long scale and high resolution is feasible.

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For the cuspate bi-cones placed in an axially uniform magnetic field, the surface magnetic charge densities are numerically calculated using the surface magnetic charge simulation method and are illustrated. From the numerical results, the demagnetizing fields and the demagnetizing factors (fluxmetric (ballistic), magnetometric, and partial demagnetizing factors) are obtained and illustrated for various cases of different relative permeability. Singular lines of demagnetizing force are obtained and illustrated to represent visually the regions in which the demagnetizing factors have minus values as the actual problems.

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Analyzed in this paper is the induced current density in the homogeneous prolate spheroid model of a biological object exposed to concurrent 60-Hz vertical electric field (1kV/m), and horizontal and vertical magnetic fields (1-5μT) with different phase angle. The analysis has been carried out separately considering the presence of electric and magnetic fields. The current density induced by electric field is calculated using finite element method (FEM). Whereas the current density induced by magnetic fields is calculated with exact solution for prolate spheroid model. Total induced current density is the vector sum of the current density components induced by electric and magnetic fields. It is found that the density of total current is determined by vertical electric field and horizontal magnetic field. The horizontal magnetic field has an important effect on the total induced current density distribution. The distribution of the density of total current varies with the phase difference between vertical electric and horizontal magnetic fields. As the model gets close to the ground, however, the contribution of the horizontal magnetic field to the total induced current density is liable to decrease.

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The fundamental and 3rd harmonic waves of loss current through a non-penetrated water treed polyethylene have been numerically calculated based on a model where current density j through channels interconnecting micro-voids is assumed to depend on electric field E as j =(σ0/h)•sinh(h•E), where h is a parameter which characterizes the electric field dependence of j. The numerical results obtained by this model give a good agreement with the observed changes in the magnitudes of fundamental and 3rd harmonic waves, I1 and I3, and their phase angles θ1 and θ3, respectively, for the application of a constant voltage. It has been concluded that the length of interconnected channels in the water treed region grows with time duration. It is also concluded that conductivity of interconnected channels shows a little increase with their growth.

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Magnetic chromatography (MC), a new application of superconducting magnet technology, is promising for analyzing ultra-fine particles with diameters of several tens nanometers, which are too large for conventional liquid chromatography techniques. Magnetic chromatography systems use ferromagnetic wires in a strong magnetic field to create high magnetic field gradients. The fluid velocity is low near the wires, so that particles with high magnetic susceptibility are drawn to the wires, and are separated from the particles of low susceptibility. Because MC columns can be easily cleaned by switching off the applied magnetic field, MC systems generate no secondary waste, which is a common problem with conventional chromatographic systems. In this report, we describe a numerical model of MC systems we developed, and show the effect of the width of particle size distributions on both the steady-state spatial particle distribution and on the MC separation efficiency. Our simulation results show that as the size distribution widens, the steady-state particle concentration increases near the ferromagnetic wires used to generate the high-intensity magnetic force, and decreases the separation efficiency at low flow velocities.

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Space Charge was measured in Cross-linked Polyethylene using pulse-electroacoustic method under a high dc electric field up to the time of dielectric breakdown. Local electric field in the bulk was calculated by integrating space charge profile. Dielectric breakdown did not occurred when the local electric field reached the maximum value but a little while after, suggesting that dielectric breakdown strength deteriorated after the local electric field reached the maximum value. The deterioration of the breakdown strength was caused by increase of mobile carriers that were generated in the insulation and were injected from cathode, where the local electric field was enough high.

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Many complex patterns in nature such as surface discharge and lightning are known as fractal objects. It is well known that the electrical trees in polymeric insulating materials are also fractal objects. However, it is difficult to analyze the real electrical trees in a 3-dimensional space. With the development of a computer system, the stochastic models for electrical trees have been presented and the fractal analysis of their simulation trees has been performed.
In this paper, we carried out the 3-dimensional simulation utilizing the stochastic model under a Laplace field, taking into account the growth probability, local field, critical threshold field and voltage drop along tree channels Using this numerical simulation model, we obtained the various shapes of simulation trees, such as branch-type, bush-type and densely bush-type trees, and estimated the fractal dimensions of their simulation trees.
The results show that the obtained simulation tree patterns have a fractal character and the parameters in an adopted stochastic model influence the fractal character of simulation trees.

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Regarding the possibility of biological effects caused by exposure to ELF (extremely low frequency) magnetic fields, magnetically induced current inside the human body has been a focus of research. To clarify the induced current characteristics inside the human body, we developed estimation tools. One was a numerical calculation code and the other was a human model. The numerical calculation code was based on a surface charge method. The human model was composed of several organs and other parts of the human body, whose shapes were spheroids or cylinders. Organs taken into account were the brain, heart, lungs, liver and intestines. The validity of the calculation code was shown by comparing it with an analytical solution using a homogeneous spheroid model. The discrepancy was within 6.5%. The applicability of the code to the human body were shown. In addition, by applying the calculation code to the human model, effects of the organ conductivity difference to the induced current distribution were estimated. As a result, the value of organ conductivity very much affected the induced current distribution inside the human body.

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We have already realized a transparent wave absorber at X-band and 60GHz. The necessity of transparent wave absorber at 1GHz band for pocket telephone is increasing. In this paper, it is proposed that the transparent wave absorber for the 1GHz band is integrated into two plates which have a glass plate and a resistive-film. Actually it is manufactured and measured the absorption characteristics expirically. Consequently, we confirmed that the realization of the transparent wave absorber.

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The uncertainty in the position operator of the Dirac electron is closely investigated based upon the method of Huang's expectation value. It is found that the obtained results are consistent with that of the previous paper.

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We selected UV lasers, which have the advantage of getting a long plasma channel in air and high repetition rate of laser operation. Consequently, the 50% breakdown voltage in oxygen and dry air except in nitrogen decreases with the burst of frequency with a KrF (248nm) laser beam. This phenomenon seems to be due to the photodetachment of negative ions of oxygen (O₂-andO-).

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