Constant monitoring of manufacturing processes has been essential in food industry because of global expansion of microbial infection. Micro-scale dielectrophoretic method is an attractive technique for direct operation and quantitative detection of bioparticles. The electrical system is capable of rapid and simple treatments corresponding to severe legal control for food safety. In this paper, newly developed techniques are reviewed for bacterial concentration, detection and sterilization using dielectrophoresis in a micro reactor. The perspective to an integrated micro device of those components is also discussed.

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The organic light-emitting diodes (OLEDs) have multi-layer structure consisting of organic fluorescent or phosphorescent dyes. Since OLEDs have such advantages as light-weight, surface emission, fast response and so on, they are a prospective component of future flat-display. In addition, white-emitting OLEDs have the potential of excellent lighting-source.

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The efficiency of dye-sensitized solar cells reached 11% which exceeded that of amorphous Si solar cells. The next target is 15 % efficiency. Focus is put on light harvesting and electron collecting performances to increase the efficiency. Tandem and hybrid cells have been reported to harvest light with wide range of wavelength. Electron collecting performances are improved by surface passivation of nano-titania particles. The research trends including our results are reported.

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Electrostatic discharge (ESD) is one of electromagnetic disturbance source. For an immunity test of ESD, IEC 61000-4-2 is standardized. In the standard, air discharge and contact discharge method is described to apply ESD to equipment under test. Air discharge, which is most commonly observed in field, is severer test than contact discharge. Air discharge is dependent on humidity, approaching speed to a grounded matter, structure of ESD generator, and so on. An ESD event during the time that a charged matter approaches a grounded matter has more significant effect on electronic equipment than an ESD event from a stationary charged matter with the same charging potential. This peculiar phenomenon is considered because rise time becomes faster and peak spark current becomes larger, but is not well understood due to the reasons such as difficulty of reproducibility. To promote the understanding of the spark discharge that occurs during the time that charged matter approaches grounded matter, the effect of changing the time of the charging voltage on the spark discharge from a stationary metal disk was measured. As a result of the experiment, the sparking voltage and peak spark current increased with a change in the time of the charging voltage, and the amplitude of the spark current spectra also increased with a change in the time of the charging voltage. The experimental results are considered from sparking resistance formula, and can be explained from the increase of sparking voltage qualitatively.

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More and more electronics are to be used under various adverse environments at high temperatures with high humidity. Spatial distributions of internal charge carriers mainly due to ionic impurities that appear in hot and humid environments are considered to affect the reliability of bulk insulation. Therefore, the authors examined space charge behavior inside paper/phenol-resin composites for printed circuit boards under dc voltages, focusing on the effect of water absorption temperature. Both the sample weight and thickness are increased monotonically by the immersion in water with an increase in water temperature from 24°C to 85°C, indicating that the water absorption by the sample is temperature dependent. In early periods of water absorption up to 10 hours, the electric field decreases near the two electrodes and increases in the other regions. Furthermore, heterocharge formation is observed near the cathode as the water absorption progresses, which becomes more significant at higher water temperatures. Ion chromatography analyses detected a lot of ions such as Na⁺, NH₄⁺ and Cl^- from the water, in which the sample had been immersed for 100 hours at various temperatures. It is highly possible that these ions are responsible for the heterocharge formation.

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This paper describes large-scale analysis for high frequency electromagnetic field by the finite element analysis of Maxwell equations including the displacement current. A stationary Helmholtz equation for the high frequency electromagnetic field analysis is solved taking an electric field and an electric scalar potential as unknown functions. Domain decomposition methods enable the acceleration of the solution to large-scale analysis problems. Hierarchical domain decomposition method (HDDM) is employed as a parallel solver based on the iterative domain decomposition method. A whole body cavity resonator: TEAM Workshop problem 29 is used as a numerical example to verify the accuracy of our analysis. Numerical examples demonstrate that the developed method can compute large-scale problems over 10 million unknowns.

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Plane gratings with small periodicity must be approximated by equivalent surface resistive sheet. In this paper, uniform approximation of equivalent surface resistance is considered for electromagnetic scattering problem of plane gratings by circularly polarized incidence. By investigating the difference between the equivalent surface resistance and the numerical values corresponding to surface resistance of plane gratings, the applicable condition of the uniform approximation is directly cleared.

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A new type pulsed ion beam source was developed by use of washer gun plasma source. It will provide low-cost and maintenance-free ion beam for the neutral beam injector (NBI), eliminating the conventional filament and water cooling systems. Its low-voltage and high-current properties are suitable for the present spherical tokamak experiment.

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