Newly introduced are electronic phonons which are reduced to vibrations of an electron network formed in the oxide superconductor materials by a strong on-site Coulomb repulsion between the outer-most electrons located on Cu and O sites in the CuO₂ plane. The repulsive inter-Coulomb interaction between the 1st neighbor sites as well as between the nearest neighbor sites is taken into account based on the estimation of the effective range of the screened Coulomb interaction. Wannier function treatment for the localized electrons and cannonical transformation of the displacement of the electron network lead to the electronic phonons whose cut-off frequencies are more than 10³ times higher than those of the conventional lattice phonons. The critical temperature estimated based on the strong-coupled phonon mechanism which is changed to a two dimensional form is obtained at around 350K in good accordance with experiment.

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We have been developing fiber-reinforced superconductors (FRS) for high-field and large-scale magnets. Tungsten fibers have been selected as the reinforcement fiber for FRS so far because tungsten has the highest elastic modulus of approximately 400GPa which can minimize the strain from electromagnetic force. The preparation process of FRS consists of sputtering deposition and heat treatment because it may be difficult to apply drawing methods to materials of high-elastic modulus such as tungsten. Tantalum has high elastic modulus of 178GPa and its thermal expansion coefficient that is closer to that of Nb₃ Sn than tungsten's, which means prestain in Nb₃Sn in FRS is reduced by adopting tantalum fibers. Tantalum has been used as barriers between bronze and copper in conventional Nb₃Sn superconductors which are usually prepared with drawing process despite of the tatalum's high elastic modulus. That implies drawing process may be applied to prepare FRS with tantalum reinforcement fibers. In this paper, FRS using tantalum fibers prepared with supttering process are described with making comparison with FRS of tungsten to clarify the basic properties of FRS using tantalum fibers. Depth profiles in Nb₃Sn layer in FRS were measured to examime reaction between superconducting layers and reinforcement fibers. Superconducting properties including strain and stress characteristics were shown. Those data will contribute to design of FRS using tantalum reimforcement fibers with adopts the drawing processes.

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There is no standard method for evaluating shielding effect of magnetically shielded room (MSR) for alternating magnetic noises at the frequency of less than several hundred Hz. Usually, the magnetic noise is intentionally applied by using a single exciting coil or a pair of coils set up outside the MSR, and then a reduction of magnetic noise due to the MSR is evaluated. In this paper, in order to establish the standard evaluation method, size and configuration of the noise generation coil is investigated by the finite element analysis and by experiments using a model MSR. In these studies, 3-D magnetic fields and eddy currents are taken into account. The MSR is a brick type and has a door as the same as the actual MSR to take account of complicated eddy current distribution due to the door. First, in order to find conditions for applying the uniform magnetic noise, the effect of the size of a pair of exciting coils on the shielding effect is discussed by setting up the coils just close to the MSR, and the effect of the distance between the coil and MSR is also discussed by using a pair of coils of small size. Second, the effect of the non-uniform noise is discussed by using the small coils which simulate near noise sources such as an electric wire, measuring equipment and so on. The following results are obtained: (1) The shielding effect for the uniform magnetic noise can be evaluated by using a pair of exciting coils larger than the size of a MSR set close to the MSR, and a pair of small coils yield the excessive shielding effect compared with the case using large coils, (2) In the case when a pair of small coils are set up sufficiently far from the MSR, the shielding effect is nearly the same as that for the uniform magnetic noise especially at several ten Hz, (3) The frequency dependence of the shielding effect for non-uniform magnetic noise is different from that for the uniform noise. Especially when a single small coil is set in front of the door for applying the noise in the vertical direction at the center point of the MSR, the shielding effect does not change at the frequency of less than about 20Hz and then diminishes gradually because of eddy currents. This tendency is different from that for a pair of large coils for the uniform noise. Therefore, it is required to evaluate the shielding effect for both uniform and non-uniform magnetic noises.

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Vanadyl phthalocyanine (VOPc) thin films were prepared with molecular beam epitaxy (MBE) technique an KBr (100) and muscovite substrates. Their morphologies are discussed with their scanning electron microscopy (SEM) images and UV/VIS spectra. The VOPc thin film on a muscovite substrate forms phase I at substrate temperature (Ts): 100°C and forms phase II (triclinic structure) at Ts: 200°C and Ts: 300°C.
The VOPc thin film deposited for 60 minutes at Ts: 80°C on a KBr (100) substrate composes of unidirectionally-oriented single crystals. The UV/VIS spectrum shows the absorption peaks at about 680 and 780nm. This indicates that the VOPc thin film has a bulk monoclinic phase. The crystals prepared at Ts: 150°C are lager than those at Ts: 100°C and have an absorption peak at 780nm and a shoulder at 810nm. This means that the VOPc thin film on a KBr (100) surface is a composite film of monoclinic and epitaxial growth crystals. At Ts: 200°C, the average size of crystals is about 1×1×0.1μn. The crystal has an absorption peak at 810nm. The film is dominated by eptaxially-grown crystals. The VOPc film prepared with MBE method is dominated by epitaxially-grown crystals with increasing Ts. This means that molecules on KBr surface can migrate with increasing Ts to form epitaxially-grown crystals.

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In order to examine the detailed distribution of electric fields induced by ELF magnetic fields in the biological structures, an approximate solution for the simple eccentric double-layered sphere is proposed and a numerical calculation method based on the conventional impedance method is employed. Results obtained by the approximate solution are compared with the numerical results, and the reasonable agreement between them is obtained, confirming that the proposed approximate solution is applicable to such models. It is found that the distribution of the induced electric fields in the 3-dimensional model reflects the inhomogeneity of the electrical properties in the model. It is concluded that the significant amount of the field components both in a radial direction and in the ambient field direction cause the distributions of the induced electric field on a certain crosssection of 3-dimensional model to be different from those obtained for the geometrically equivalent model of 2-dimensional eccentric cylinders

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The bushing of transformer is one of the parts of the transformer system, but is vital as well as transformer itself because it forms a part of the main circuit. Deterioration and abnormal condition of the bushing possibly cause its destruction, shortage of the main circuit to the earth, and fire of the systems so the diagnosis of the bushings is very important. At the present, the Inspection by eyes from the outside of the bushing is mainly carried out. The inspection of the inside conditions of the bushing by the dissolved gas analysis of the inside oil is done only as sampling for not all but selected bushings because it is difficult due to the sealed construction of the bushings. Therefore a simple diagnostic method for the bushings has been expected for a long time. In east Europe, RVM (Return Voltage Measurement) method based on scanning the polarization spectra was applied to the oil-paper insulation systems inside the transformer as a diagnostic method.
In this paper we investigate theoretically the principle of the RVM method which is applied to the bushing with the same oil-paper insulation systems as the transformer by using the equivalent circuit, and a possibility of this novel diagnostic method for the condenser type bushings is demonstrated by the model experiment.

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In a design of electric devices, it is important to know the relation of the magnetic properties between the raw materials and the core. This paper describes the magnetic properties of tape wound ring core considering the influence of magnetization conditions and dimension ratio under ac excitation. In the analysis, magnetization characteristics are approximated by a Fourier series, and it is assumed that the eddy current factor is proportional to the rate of change of the flux. From the result of numerical analysis, the influences of oprating flux density, frequency, wave forms of input voltage on the relation between dimension ratio and ac magnetic properties are shown. The results of the analysis were confirmed by the experiments.

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PE film with additive was prepared by the solution-grown method. The thickness of the film ranged from 5μm to 20μm. Three kinds of additives were used: p-aminoazobenzene (ab), p-nitrobenzene-azoresorcinol (nbl) and p-nitrobenzeneanaphthol (nb2). Concentration of additive to PE was in the range from 0.005wt% to 0.5wt%.
DC breakdown strength (Eb) depends on the kind of additives in the temperature range from-20 to 30°C. Eb increases in tlle following order: (PE)<(PE+ab)<(PE+nb1)<(PE+nb2)>. Eb for the film added with nb2 (PE+nb2) is 1.5 times higher than that fbr the film without additives (PE) at-20°C. Since Eb decreases with the increase in the thickness and Eb depends on cathode material, it was considered that the breakdown of the film resulted from generation of the electron avalanche. The conduction current through the film in high strength region of electric field also depends on the kind of additives. The current decreases in the following order: (PE)>(PE+ab)>(PE+nb1)>(PE+nb2). The additives may act as electron traps and may absorb the kinetic energy of electron at the collision. It was estimated from the results that the trap level for nbl and nb2, which have electron-acceptor group, is deeper than that for ab, which has electron-donor group. The absorption of the energy due to excitation for nb1 and nb2 was also estimated to be more significant than that for ab.
The order for the decrease in the conductive current corresponds with the order for the increase in Eb. It was considered that the generation of electron avalanche is controlled when the smaller conductive current is achieved by the additive. The smaller current will ensure the higher Eb.

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Acid rain is one of the more serious environmental contaminations. Some research results have shown the influence of acid rain on the tracking resistance of outdoor polymer insulating materials. The degradation effects of acid rain on the outdoor composite insulators of silicone rubber and Ethylene Vinyl Acetate (EVA) are investigated by the accelerating aging of artificial acid rain in this paper. Based on the investigation of acid rain, the artificial acid rain is chosen to agree well with the actual ingredients of precipitation. Furthermore, the influence of hydrophobicity degradation on the surface discharge current of insulators is studied. The relations among the hydrophobicity degradation, micro chemical structure and physical morphology of material surface layer are discussed. Test results show that the insulators suffer a large attack and degradation from acid rain. The surface becomes rough, hydrophobicity decreases and surface discharge currentincreases. The erosion of acid rain on the insulating materials in power system is larger than that on the outdoor materialsfor the other purposes. Silicone rubber shows a larger resistance against acid rain than EVA.

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A ferrite loaded radio-frequency (rf) cavity with resonant frequency of several MHz is commonly used for proton synchrotrons. It became clear from our study that Ni-Zn-Co ferrites were preferable to Ni-Zn ferrites for the rf cavity because they had low rf loss due to their induced magnetic anisotropy by Co ions. Therefore, we tried to improve existing Ni-Zn-Co ferrite by controlling CoO content.
This paper presents test results of rf characteristics for the improved ferrite with large diameter of 500mm, using a ferrite test bench. Compared with the ferrite "4M2" supplied by Philips, our improved ferrite has superior rf characteristics both for dc bias field and ac bias field. Especially, the high loss effect, which is troublesome in dc bias operation, is considerably suppressed. If we can increase its mechanical strength without deterioration of rf characteristics, this ferrite will be applied to actual rf cavities.

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An impedance measuring method (IML) based on the least squares method is consists of a pair of current-to-voltage converter (CVC) composed with an operational amplifier, a personal computer equipped with a pair of analog-to-digital converter, an ac voltage source. Two impedances ZP and ZQ are connected with the ac voltage source in parallel. Each current flowing through ZP and ZQ is converted to a voltage with the CVC. An amplitude and a phase of the voltage are estimated by the least squares method. Then, a ratio of Zr to ZQ is calculated.
Resistance ratios of 1:1 and 3:1 composed with some combinations of metal film resistors of which nominal values are 1, 3, 100 and 300 [kΩ] are measured by this method in frequency range of 100[Hz]to 20[kHz]. It is estimated that the uncertainties of the average values of 10 measurements are less than 0.005[%] in magnitude and 0.05 [mrad] in phase angle.

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A plasma horizontal position feedback control system (PHPFCS) and a digital current dirve (DCD) for control vertical magnetic field are made on an experimental base and the horizontal position of a plasma in a small tokamak (HAMANA-T) is controlled by PID operations from the initial phase of plasma generation. DCD consists of constant-current discharge units for plural condensers and drives a digital current analogous as a whole to the control signal of PHPFCS in the range of ± A. The maximum value of the digital current increases in proportion to the number of units. This PHPFCS elongates plasma duraton from 1.3 ms to 2.1 ms, makes smooth the wave form of plasma current and reduces plasma loop voltage from 25 V to 20 V. Furthermore, PHPFCS reduces the range of variation in plasma horizontal displacement from 3.5cm to within 0.5cm and makes it possible to set accurately the horizontal position from the initial phase in inner region of a vacuum chamber.

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The purpose of this paper is to explain the constant power characteristic of the constant power type operating circuit of the high pressure mercury arc lamp on the basis of the waveform analysis, and to investigate the behavior of the higher harmonics to elucidate their generation in the nonlinear load. Rated voltage of sinusoidal waveform is applied to the input terminal of the operating circuit. As thee input voltage is varied after steady state, the waveforms are analyzed. The experiments and their analysis are conducted in the following way. And the differences from other operating circuit are indicated.
(1) The waveform of the voltage and current with distorted form for each element of the operating circuit is analyzed, and the impedance for each harmonic component is calculated. (2) From the results of the waveform analysis mentioned above (1), vector diagrams of the voltage and current for each harmonic component of the operating circuit are elaborated. (3) From the results of the waveform analysis mentioned above (1), equivalent circuits for each harmonic component of the operating circuit are elaborated. (4) The consumption power for the operating circuit are calculated to make sure it is constant, and its reason is explained.

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The applied voltage used for ac-PDPs is a rectangular wave whose rise time (less than 100 ns) is very fast, while the applied voltage used for an ozone generator is a low frequency sinusoidal wave. We take note of this point and study the effect of the rise time of the applied voltage. Changing the rise time, we can see the relationship between PDP discharge and low frequency silent discharge experimentally.
According to the PDP discharge model, we made a theoretical equation to calculate the discharge power input of ac PDPs for the first time. We generalize the equation to the PDP discharge with the applied voltage of slow rise time. Then we can make clear the relationship between PDP discharge and low frequency silent discharge theoretically.

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We have studied luminous layers phenomena in Ne by experiments and a Monte Carlo simulation (MCS) method. In our previous paper, we mentioned that the calculated spatial distributions of excitation using MCS are in agreement with the observed spatial emission distributions of visible light. Therefore, it was found that the luminous layers were able to explain by means of the collisional excitation of electrons.
This paper describes the curved phenomenon of luminous layers. We performed the precise MCS not only in Ne but also in He, Ar, Kr and Xe under the same gas pressure and gap length condition. The discharge space was divided into 240 sections in the field direction where the length was 1.2cm and 6 sections in the radial direction where the radius of electrode was 0.6cm. Our research paid attention to the spatial distribution of excitation which produces the luminous layers. It was found that these layers are curved like the observed luminous layers. We also investigated the relationship between the spatial distribution of excitation and the collision rates which includes elastic collision νm and excitations νe. We found that the position of drifting electrons are far from the center of the axis, spatial distribution of νm and νe along the electric field direction shifts to the anode. This shows that the net electron energy loss by collision with atoms becomes smaller as the electron lies near the center of the electrodes.
We concluded that, if the position of the electron shifts perpendicularly to the direction of the electric field, the elartrnn will suffer the enemy loss as the result of the increase of elastic collision.

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armature rail gunsystem, a current concentration on the rail/armature interface due to a velocity skin effec must be reduced to get the higher velocity. 2-D numerical caluculation shows that the shape of solid armature is important on reducing the current concentration, by which a characteristic length of the magnetic gradient on the rail/armature interface is extended.The optimum shape depends on values of the armature velocity and the permeability and resistivity of rail material.

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We investigated the surge phenomena between crossing conductors at right angles in experiment for miniature line model and in simulation by numerical electro magnetic field analysis. The induced voltage is influenced by the steepness of the applied voltage. Because of the insufficient simulation of applied voltage, the difference of the peak voltage between the measurement and the simulation is about 20%. However, the equivalent mutual static capacitance between conductors is independent on the steepness, and has the difference of less than 8% to the measurement. The conventional approximation of the capacitance between infinite conductors showed the large difference in the capacitance as the approximation of the function of the radius, height and the length of the conductors. To set up the fine approximation of the capacitance, we simulated the electro magnetic field in various arrangements of the conductors. From the results, we find the equation of capacitance, which is computable by an electronic calculator. In addition to the numerical electromagnetic field analysis, we performed the circuit analysis by EMTP using the capacitance calculated from the approximation, and the simulation showed the peak of the induced voltage within an error of several percentages to the measurement.

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Discharge characteristics of nitrogen gas and synthetic air at 293K and 93K under the condition of a constant gas density are investigated in a rod-to-plane electrode, applying positive lightning impulse voltage. The electrode whose tip radius is 0.04-5.0mm and whose gap length is 20mm is placed in a cryostat in which nitrogen gas or synthetic air is filled at 0.1MP under a room temperature condition. Discharge propagation is observed with a high speed framing camera. The charge quantity of corona streamers Q is measured as a function of their inception voltage V. The streamers starting from the rod can reach the plane electrode before the final breakdown of the gap occurs. In a case of the breakdown, one of the streamers remains to be faintly luminescent holding a small current after it ceases to propagate and then its emission and current restart to increase suddenly up to a breakdown level. Direct breakdown occurs only in nitrogen. The relation between Q and V changes with the gas temperature. The Q-V curve shifts to the direction of higher voltage at a cryogenic temperarure. The charge quantity of the streamers propagating at a cryogenic temperature is smaller than that of the streamers at a room temperature.

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For the infinitely extended magnetic bi-wedges placed in a uniform axial magnetic field, the surface magnetic charge densities are numerically calculated by the surface magnetic charge simulation method. From the results the surface magnetic charge density distributions and the local demagnetizing factors are obtained and illustrated for various cases of different top tingles of wedges and relative permeabilities. Especially, those characteristics around the apex of wedges are shown in detail and are discussed.

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