Miniaturized magnetic pulse compression circuit having function of automatic control has been developed. In the circuit, discrete semiconductors were connected in series-parallel, mutually for increasing the switching capacity. The pulse width of output voltage decreased by optimizing the primary windings and line length. The developed power supply was operated at an output voltage of 31.2kV, an energy efficiency of 86.9%. The automatic control of output voltage could be realized by feedback control using PIC (Peripheral Interface Controller). The output voltage was changed following the voltage setting value and the time to reach a target voltage was shorten by increasing the operation frequency.

We discuss the death process of human cervical cancer cells HeLa S3 induced by two types of non-thermal intense electrical pulses of different durations and amplitudes, 120 ns-long, 12.5 kV/cm and 5 ns-long, 250 kV/cm. WST-8 assay was used to evaluate the cell viability. Expression of three proteins associated with the stress response, Caspase 3, ASK1 and BAX, were analyzed by using the antibody assay and flowcytometry. Apoptosis activity was evaluated by means of the TUNEL assay and flowcytometry. Also, Ca²⁺ dependences of the death process and the protein expression were explored by using the metal ion chelating agent, EDTA. Our experiments demonstrated that 5 ns and 120 ns pulses give quite different biological stresses leading to the different death process and the protein expressions. The cell death induced by 120 ns pulses are dependent on the presence of Ca²⁺ and accompanied by expression of proteins associated with apoptosis and stress response. Conversely, the protein expression induced by 5 ns pulses was independent of the presence of Ca²⁺, whereas the death was Ca²⁺ dependent.

In this study, we have demonstrated effects of atmospheric pressure plasma generated by superimposed voltage waveform pulsed-power supply on treatment of Escherichia coli (E.coli). The growth rate of E.coli is evaluated with a measurement of optical density. The results show that the growth rate of E.coli with the irradiation of atmospheric pressure plasma without superimposed voltage waveform decreases. On the other hand, the growth rate of E.coli with the irradiation of atmospheric pressure plasma with superimposed voltage waveform is similar to the control condition. These results suggest that the irradiation of atmospheric pressure plasma with superimposed voltage waveform affects the growth rate of E.coli.

In these days, the electric power is essential for our life. The electronic technology makes rapid progress and the electrical instruments get our life to be convenient. However, some of them have the circuits generating the harmonic. For that reason, the wave of electric current in electric power distribution system can be distorted, and it gives a lot of instruments damages. Therefore, measuring the quality of electric power is needed for supplying the stabilized electricity. In this study, the authors have developed a system for analyzing the power factor and the direction of harmonics with FA computer. When the users measure the states of electric power, they can use it through Web browser. In this system, FA computer measures the voltage and current, performs AD conversion, and sends data to a remote Web browser. The Web browser calculates the power factor and the direction of harmonics, and displays the result of analysis.

Magnetorheological elastomers (MREs) are composed of silicone elastomers and iron powder so that they can possess ferromagnetic and viscoelastic properties. The shape and the stiffness of the MREs change depending on the magnetic field. Therefore, it is expected to be used for an artificial muscle or damping material. However, it is difficult to device design because ferromagnetic and viscoelastic properties greatly change depending on ratio of the iron powder and strength of magnetic field. This paper presents a numerical method for MREs analysis by coupling a particle method with a finite element method (FEM), in which the nonlinearity of MREs as Young's modulus, Poison's ratio is taken into account. The numerical algorithm is described and calculated results are shown.

Gas-insulated switchgear (GIS) has been widely applied since 1968 in Japan due to the compactness and high reliability, and has the brilliant history during this half century. This paper looks back of the GIS history from a view point of transition of the technological development and practical application. The GIS history is roughly divided into four stages: 1) early stage of GIS development and practical application (1963-1976), 2) expansion of GIS application (1977-1990), 3) advancement of GIS (1991-2000), and 4) maturity of GIS (2000-present). The research and development (R&D) for GIS started from 1963 followed by the practical application of 84 kV GIS (1968) up to the first 550 kV GIS (1973) during only a decade. In this paper, the early stage is focused on as the first report of GIS history in Japan. First, the aim and significance of studying GIS history is mentioned, and secondly, the details from the R&D to the application of GIS up to 550 kV class are described. Finally, the authors try to discuss the differences of the R&D and practical application between domestic and overseas in terms of the following two items: the way of R&D and application (comparing the collaborative work system by manufacturers and users), and the basic GIS design (an example of the rated gas pressure).

Nowadays as the development of cell phone and satellite communications, liquid crystal materials have attracted considerable attention for realizing these electrically controllable microwave and milliwave components. As usual, nematic liquid crystal is mainly used for microstrip line (MSL) phase shifter, but when driving voltage is removed the response time is very long. In this study, we discuss about using polymer stabilized nematic liquid crystals with UV polymerization for improving the response time in MSL phase shifter in which phase shift is about two times larger than that in CPW phase shifter.

Confronting divergent magnetic fields (CDMFs) applied to an inductively coupled plasma have a function to confine electrons within the source region. We discussed judgement criteria for electron escape from the source region to the diffusion region across the separatrix of the CDMFs. Passage of electron gyration center across the separatrix and collisional events in the diffusion region were newly introduced as effective criteria.

Leader length of a gap in a parallel gap configuration at the flashover of one of the gaps is theoretically analyzed. The analysis is based on the leader development characteristics and statistical characteristics of time to flashover. Calculated results agree very well with experimental results previously reported.