Artificial heart (AH) study has been started in 1957. After the accomplishments of various difficulties, the AH can become to use clinically as a postcardiotomy cardiac assist or bridge to heart transplantation. However, there remain many obstacles to realize an implantable total artificial heart. The history of AH was the self-making. Although self-making is important in all the experimental sciences, it is the most important factor to develop AH.
In this paper, the author would like to introduce the present status of AH and the importance of self-making.

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We examined the electrical conduction and dielectric properties as well as thermal analysis of polylactic acid (PLA) that is biodegradable plastics. From the results of thermal analyses, it was found that the glass transition temperature (T_g) of PLA was about 60°C and the melting point (T_m) was about 166°C. For the temperature dependence of current density (J), J of PLA became smaller than LDPE, PP and Polyester in the temperature from room temperature to 90°C. However, when sample became 90°C or the higher, J of PLA became larger than other plastics. On the other hand, as a result of measuring J of the same sample again, it became small. For the relative permittivity (ε_r') indicated intermediate values between that of polyester and those of LDPE and PP.

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Experiments on transformation of energy and beam current waveforms of an intense relativistic electron beams were carried out. An intense electron beam with energy of 500 keV, current of 3 kA and duration of 12 ns was injected into a drift tube. A coaxial cavity connected with the drift tube via a gap was utilized to transform the time evolution of electron energies of the beam. The scheme is the same as the autoacceleration except the cavity length. The former part of the beam with duration of the round trip time of the cavity lost the energy and following part of the beam with the same duration gained the energy. A cylindrical cavity with large radius was located behind the coaxial cavity to change the time evolution of current waveform of the beam. The injected beam current larger than the space charge limiting current at the cavity was decreased gradually to the limiting current by elongating the cavity length. Trapezoidal waveforms of injected electron energy and beam current were transformed to the time-increasing waveforms after the cavities.

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The authors have proposed the resin molded type of voltage-current sensor for the real time observation of the power facter. The sensor has been designed and implemented based on the FEM, however, the current waveform in the practical power distribution system includes harmonic components due to the inverter-fed power apparatuses in households and factories. Therefore, it is necessary to apply not conventional jω method but finite-difference approximation on the time derivative term in a transient electromagnetic field analysis using FEM. In the paper, we will show the result of electromagnetic field analysis of the sensor adopting the finite-difference approximation.

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We performed measurement of the radio frequency power and temperature of electrodes and plasma parameters of rf discharge. The purpose of this research is checking the accuracy of the measurement of energy consumed in plasmas. The heat energy in plasma was obtained by heat flux that was calculated from substrate temperature. The temperature was measured by the laser interferometer using the LiNbO₃ crystal. In the case of 2 cm and 3 cm and 4 cm electrode spacing, the heat energy toward electrodes was 7.7 W and 5.4 W and 4.0 W, respectively. The current and voltage measurement was made at the driven electrode. The input power was 8.2 W and 5.1 W and 7.7 W for the electrode spacing 2 cm and 3 cm and 4 cm, respectively. The heat energy calculating based on the electron density distribution measured was conducted by estimating the Bohm flux and ambipoler diffusion flux. It was found that the heat energy toward electrodes was 1.4 W and 1.8 W and 1.5 W for the electrode spacing 2 cm and 3 cm and, 4 cm, respectively, and the heat toward the wall was negligible.

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The Lattice Boltzmann Method (LBM) which is derivative of the lattice gas automata (LGA) has recently studied as a numerical scheme for simulating fluid flows governed by the Navier-Stokes equation. The LBM is a discrete numerical method based on the Boltzmann equation. The dynamics of the LBM is divided into a propagation step and a collision step. We have proposed a model for weakly ionized plasma by introducing diffusion as a velocity to LBM. In our LBM model, ionization, recombination at the wall and ambipolar diffusion are considered. This model uses 2D9V (2 dimensions, 9 velocities) model and BGK collision operator. We have simulated various shape of discharge tubes by this model. MATLAB is suitable for matrix calculation and has a command for shifting matrix which is important in LBM. By this work, it is shown that our model simulates weakly ionized plasma well.

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Since high-pressure mercury lamps have high luminance and emit large luminous flux, they are widely used for outdoor lighting. One of the problems of them is difficulty to re-ignition just after turn off because of high mercury vapor pressure during discharge. One solution is to make photo pre-ionization in the lamp to reduce starting voltage. In this study, ultraviolet laser beam from XeCl excimer laser is introduced to the lamp and the phenomena occurring between laser inlet to starting discharge have been investigated. From the calculation of the time required for ions and electrons to drift between electrodes, it is found that the streamer is formed and it makes an important role to start discharge. Moreover, multi-step discharge was observed and under this condition probability of starting discharge decreased.

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The effect of shearing on iron loss and domain structure of non-oriented electrical steel was studied. From the hardness distribution in the vicinity of sheared edge, the iron loss increase due to plastic strain introduced by sharing was estimated to be 1/3 of the actual loss deterioration. The remaining 2/3 was considered to occur in the region where the width was about twice the sheet thickness, where the domain pattern was influenced by the shearing. Cross-sectional domain patterns in the vicinity of sheared edge were found to be categorized into three types depending on the distance from the edge.

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We study an electron acceleration by using a focused TEM₁₀ + TEM₀₁ mode laser pulse with a plasma separator in vacuum. By using the TEM₁₀ + TEM₀₁ mode laser and the plasma separator, the electrons are accelerated strongly compared with that in the case of a TEM₀₀ mode laser, and the divergence of the electron bunch accelerated is suppressed in the transverse direction by the transverse ponderomotive force of the laser. In both the TEM₀₀ mode laser and the TEM₁₀ + TEM₀₁ mode laser, the electrons are decelerated by the laser at the deceleration phase of the laser pulse tail. In order to suppress the energy loss, we set an overdense plasma separator before the electrons are decelerated by the laser tail. Only the laser pulse is reflected by the plasma separator, and the high energy electrons pass through the plasma separator without the energy loss at the tail of laser pulse.

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The temperature dependence of electrical conduction current in additive-free poly-L-lactic acid was measured from 20 °C to 90 °C under application of dc 2.5 kV. Although the current obeys the Arrhenius formula, a hump appears in some conditions, depending on whether the temperature is being ascended or descended, and also on whether the sample was poled or short-circuited prior to the measurements. Even under short-circuit condition, a similar hump alone appears if the sample was poled by a dc voltage beforehand. From these results, it is assumed that orientational polarization or depolarization occurs around 74 °C by the glass transition, and that its resultant current and the conduction current overlap with each other. The fact that polar groups, mainly carbonyl groups, in the sample really changed their directions was confirmed by Fourier-transform infrared spectroscopy. The permittivity also increases around 74 °C. These facts indicate that the number of dipoles, which become possible to rotate toward the direction of electric field, is increased by the glass transition.

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We studied the effect of inverter surge voltage for high voltage electrical insulation by using steep fronted and high frequency high voltage pulse generator and model bar coils. In this experiment, we investigate the lifetime and partial discharge characteristics of insulation under surge voltage with various risetime, pulse width, magnitude and polarity. In these results we found little difference on insulation lifetime applying surge voltage with 1μs risetime , between 10μs and 100μs pulse width, compared with lifetime of conventional sine voltage under the same peak voltage and repetitive frequency. We also found the polarity effect of surge added in AC voltage for insulation lifetime is little, but the lifetime of insulation decreases with the magnitude of surge added in AC voltage even if under the same voltage peak applied. These results are discussed with partial discharge characteristics and it is found that it is necessary that the peak voltage of inverter is smaller than that of sine voltage, magnitude of surge is smaller than 1/4 of the peak to peak voltage and repetitive frequency is lower than 1kpps at least if we get the almost same lifetime of motor insulation supplied by sine voltage.

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The initial spherical tokamaks were found to disrupt in a certain low-q regime during their merging start-up. In that range, no plasma current was inductively generated by the flux cores due to large n=1 mode activity suggesting that this disruption was caused by Krusukal-Shafranov limit.

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This paper present some experimental results observed by pulse hole injection with thin film emitter. The transient current decrease exponentially to constant current and step functional increase at 12 μs occurs with single or several burst pulses, during pulse hole injection (20 μs duration). After 20 μs duration, the transient ionic peak current occurs. The breakdown phenomena concern with the burst pulse.

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Experimental results on characteristics of viscosity η of unimodal and bimodal alumina/epoxy mixtures are shown and discussed based on theoretical consideration. Spherical alumina particles with nominal diameters of 35μm and 80μm, both of which had narrow dispersion of diameter distribution, were used as fine and coarse particles, respectively. η of the unimodal mixture increases remarkably with a volume packing fraction of particle νp, and that Brinkman equation can be applied to estimate η from ν_p. On the other hand, η of the bimodal mixture depends not only on ν_p, but also on the ratio of coarse particles to fine ones. For larger ν_p, η of the bimodal mixture becomes smaller than that of the unimodal mixture. It is shown that an approximation procedure of η yields reasonable estimation for smaller ν_p, and underestimation for larger ν_p.

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