We investigated the discharge phenomena of Teflon FEP (fluorinated ethylene-propylene) films used as thermal control material of spacecraft by electron beam irradiation simulating hot plasma in space. FEP films of two kinds of thickness, 25μm and 127μm, were tested. The obtained experimental results were as follows.
(1) In 127μm thick FFP film, surface discharge triggered by high electric field at the triple junction of the edge of the metal frame occurred.
(2) In 25μm thick FEP film, punchthrough discharge accompanied with surface discharge occurred.
(3) Discharge frequency increased with the nearly 1/2 power of the electron-beam current density under the constant irradiation energy. On the other hand, it increased linearly with the irradiation energy under the constant beam current density. However, the threshold electron energy to cause the discharge existed.
These results were explained by comparison between the surface electric field and the bulk electric field in FEP film obtained analytically by using a two-dimensional charging model.

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Serious failure of the latest high-tec equipment occurs easily due to electrostatic discharge (ESD), which is known to be often caused by electriflcation phenomena of human-body walking on the floor. On the one hand, it has widely been accepted that the ESD is difficult to happen in the high humidity environment, on the other hand this mechanism is not well understood. In order to study the electrical factors that govern the walking electrification in the high humidity environment, we measured electrical parameters (capacitance: C_s, resistance: R_s) of the commercially available shoes having synthetic rubber soles that determine the potential of the human body walking on a metal plate. As a result, we found that an equation of "C^ε _sR_s= constant" holds regardless of the humidity and the power number ξ for the rubber sole shoes falls in the renge from 3 to 5, which can theoretically be explained from moisture absorption properties of the dielectric material.

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The torque, to some extent, is an important performance index of electric motors. In many permanent magnet DC motors, the armature core is slotted with the winding embedded into the slots. What kind of force occurs on the armature teeth (or slot) and hence forms the torque is an interesting problem. In the past some relevant researches were reported, which concluded that all torque came from the force generated in the flanks of the armature teeth, and the force on the teeth surface facing the field magnet contributed nothing to the output torque. The objective of this paper is to investigate the overall electromagnetic force distribution in the armature teeth of a permanent magnet DC motor. An U-shaped core is employed as an analytical model which covers only one tooth pitch of the slotted armature, and the derivation of the force on the surfaces of the U-shaped core is obtained by means of the Maxwell stress method. Experimental results show that both tangential force on the teeth surface facing the field magnet and normal force in the flanks of the teeth contribute to the motion of a rotor. The analytical method and force expressions are verified by the experimental results.

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This paper describes to analyze on total offset pressure from which caused to eddy current and thermal expansion in a spinning rotor. Although, these offset pressure damp to spinning to caused from vertical magnetic field and from self thermal expansion, mainly estimated to totally amount of eddy current's effect which was decided by distribution of all part of the magnetic flux density of a spinning rotor. Then, it was calculated to distribution of magnetic flux density in a rotor by a finite element method which used to an application software. lt was result in constant amount and pararell to vertical magnetic field. Then, eddy current of the rotor will estimated to zero that caused to same amount and to collect from all directions with symmetrically. lt is important that to keep the high accuracy within zero-total offset pressure as constructed from symmetrical spinning condition and to protect incline the vertical spinning axis.

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When semicrystalline polymers such as polyethylene and polypropylene crystallize, they form spherulites and transcrystals. The spherulites grow from nuclei in the bulk and the transcrystals grow from the interface of two different materials during the crystallization of polymers. Spherulites and transcrystals are formed in polymers used as insulation materials; however, the deterioration mechanism of the electrical properties of these materials has not been established.
To study the relationship between the superstructure of semicrystalline polymers and their dielectric breakdown strength, we observed the structures of spherulites and transcrystals using a polarizing microscope, and at the same time compared the dielectric breakdown strengths.
The results indicate that the dielectric breakdown of transcrystals occurs at a higher field strength thanthat of spherulites for ac as well as dc voltages.

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Contactless and real-time measurement of a voltage wave form and a current one in general three phase power distribution systems is indispensable for the maintenance, the control and the stable voltage regulation and has been surveyed and tested. We have investigated the cause of a problem on the phase shifting, which influences on the precise estimation of the reactive power in low power load condition, between the actual voltage wave form and the measured one using the static induction type of the voltage sensor, which this voltage sensor comprises a pair of electrodes to measure the voltage wave form by the electrostatic induction. This paper presents the electric field analysis of the static induction type of the voltage sensors with cylindrical electrodes using 2-D FEM taking account of the unknown equipotentials and the complex permittivity.

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In this research, a diffuse glow discharge generated by a double discharge is used to improve the efficiency of the ozone generation. In this method, corona discharge occures in space between the cathode and the trigger electrode covered with Pyrex glass tube which is set in groove on the cathode. Much initial electrons are generated around the cathode.
In present research, experiments were done using air (O₁/N₂ mixture) at atmospheric pressure and the discharge repetition frequency was 1[Hz] for all experiments. The maximum ozone concentration generated by that experiment was about 150[ppm]. The average ozone yield was about 400[gO₃/kWh] that is much higher than the typical yield, about 100 [gO₃/kWh]. The efficiency of energy transfer from stored energy in capacitor C₁ to the main discharge was about 40-50[%] at large stored energy.

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The author has considered an ozone generation method using electrical discharge by means of separating the ozone generation process into an oxygen atom formation process and an ozone formation process. In the oxygen atom formation process, a nonequilibrium electric discharge dissociates oxygen molecules into oxygen atoms efficiently under a low gas pressure (less than a few tens [Tory]), and a high gas temperature (more than 700[k]). The oxygen atoms have a considerable long life time under such a low gas pressure and a high gas temperature. In the ozone formation process, the oxygen atoms are mixed with air, the 2nd material gas, to be efficiently converted into ozone molecules by three-body collisions under a high gas pressure (more than 760[Torr]) and a low gas temperature (less than 350[k]). The concept of a novel ozone generator with 0/03 different space generation system is constructed with combining the oxygen formation process and the ozone formation process without loss of oxygen atoms during transportation. According to the simulation result, it can generate the 03 of 0.498[mol%] with the efficiency of 280[g/kwh] by 1 stage reaction system and the 03 of 2.93[mol%] with the efficiency of 172[g/kwh] by 4 stage one. In comparison with the silent discharge ozone generator, 0/03 same-space-generation system, the 0/03 different-space-generation system has the following advantages; (1) Reduction of energy loss by ion current, (2) Removal of ozone destruction by electrons in the discharge space, (3) Reduction of oxygen material gas by replacing the large part of the oxygen material gas into air.

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We have developed an inner coating system by using transported coaxial ECR plasmas. The ECR plasmas generated inside a coaxial tube were transported along the tube axis by controlling applied magnetic field. The ECR plasma was generated nearby the resonance points aspressure was decreased. It was found that the control of plasma position was possible at pressures below 1 mTorr. Increases of the electron density and the deposition rate were achieved by generating mirror magnetic field.

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With instruments, equipment, and systems becoming highly integrated and provided with intelligent functions, serious and wide-spread cases of noise interference are increasing. Isolating technologies, which enable smooth operation of enfire systems by separating and isolating the electric circuit at key points and transmitting signals and power through different forms of energy, are thus becoming indispensable as countermeasures.
In a power circuit, the noise cutout transformer is the element that serves the role of isolation.
However, utilization of this element has been lagging due to there being several difficult problems in terms of magnetic coupling. Development and improvement of this element are thus urgently needed.
The function of a noise cutout transformer is to discriminate between the fundamental wave component in the coupling magnetic flux and the high frequency components corresponding to noise so that the mutual inductance between the primary and secondary coils is effected only by the former component. To achieve this purpose, it is considered essential for the coils to be separated from each other, instead of arranging them close together as in a conventional transformerso that the high frequency magnetic flux, which is generated by the primary coil and passes through the air gap and insulation, will not interlink with the secondary coil.
In this paper, the structures that can be considered for application to an actual transformer and the effects that such structures can provide shall he determined and classified through theory and experiment.
The anticipated effects shall then be examined comparatively to contribute to future development and improvement.

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Ferrite loaded radio-frequency (rf) cavity with resonant frequency of several MHz is commonly used for proton synchrotron. Resonant frequency of the cavity is shifted upward during the beam acceleration by increasing the bias current. Because the bias current is swept sinusoidally at high repetition rate, rf characteristics of ferrites deteriorate considerably due to the disappearance of induced magnetic anisotropy by Co²⁺ and Co³⁺ ions.
This paper presents test results of rf characteristics for three ferrites with large diameter over 500mm using a ferrite test bench. The rf frequency and ac bias current vary from 2MHz to 3.3MHz and from OA to 1000A at maximum frequency of 75Hz, respectively. As the frequency of ac bias current becomes high, deterioration of rf characteristics and increase in ac bias current were observed. Consequently, it was verified that the ac bias test with full rf power using the test bench is inevitable for designing actual rf cavity.

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By exposing low-density polyethylene to an atmosphere of fuming sulfric acid, sulfonated low-density polyethylenes (SPE) were prepared and the degree of surface sulfonation for treated film was determined as the weight-increase per unit area. Polypyrrole (PPy) films on the surface of SPE were grew using molecular selfassembly process and the properties of PPy/SPE composite films have been investigated. Then, the functional applications of PPy/SPE composite films have also been proposed and especially the movement properties of actuators using PPy/SPE composite films were mentioned.

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Attenuated total reflection (ATR) properties have been investigated for tilt angles of liquid crystal molecules, SCB, in the liquid crystal cell with the polyimide (PI) LB alignment films on the aluminum electrodes. The ATR curves strongly depended upon the voltages applied to the cell. The resonant excitations of the surface plasmon wave modes and the guided wave ones were observed in the ATR measurements. The tilt angles of the liquid crystal molecules were calculated on the LB films and in the middle layer region of the cell by fitting the theoretical ATR curves to the experimental ones. It is thought that the ATR measurement is very useful for evaluating the aligning properties of liquid crystal molecules in liquid crystal cells.

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