The Dielectrophoresis (DEP) is electrokinetic motion of dielectrically polarized materials in non-uniform electric fields. DEP has been successfully applied to manipulation of nanomaterials including carbon nanotubes, metallic nanoparticles and semiconducting nanowires. Under positive DEP force, which attracts nanomaterials toward the higher field region, nanomaterials are trapped in the electrode gap and automatically establish good electrical connections between them and the external measuring circuit. This feature allows us a fast, simple and low-cost fabrication of nanomaterial-based sensors based on a bottom-up basis. This paper firstly presents a theoretical background of DEP phenomena and then reviews recent works of the present author, which were aimed to develop nanomaterial-based sensors, such as a carbon nanotube gas sensor and a ZnO nanowire photosensor, using DEP fabrication technique.

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Recent progress of agricultural and food processing applications of pulsed power is described in this paper. Repetitively operated compact pulsed power generators with a moderate peak power have been developed for the agricultural and the food processing applications. These applications are mainly based on biological effects and can be categorized as decontamination of air and liquid, germination promotion, inhabitation of saprophytes growth, extraction of juice from fruits and vegetables, and fertilization of liquid medium, etc. Types of pulsed power that have biological effects are caused with gas discharges, water discharges, and electromagnetic fields. The discharges yield free radicals, UV radiation, intense electric field, and shock waves. Biologically based applications of pulsed power are performed by selecting the type that gives the target objects the adequate result from among these agents or byproducts. For instance, intense electric fields form pores on the cell membrane, which is called electroporation, or influence the nuclei.

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In this paper, we study on the maximum read range of 2.45GHz passive RFID tag when metallic plate existed behind it. From a theoretical analysis, computer simulation and experiment result, they reveal that if the RFID tag and metallic plate are separated by several mm, it is able to achieve the same read range as free-space environment. Additionally, we also include comparative study of dipole antenna model and μ-chip antenna model. Simulation result shows that the use of dipole antenna model can bring the same performance with shorter analytical time compare to μ-chip antenna model. Finally, experimental study was conducted to confirm the validity of previous analysis.

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The relationship between a three dimensional electric potential distribution and electron trap depth in polymeric material was discussed. A semi-empirical method of molecular orbital is applied to calculate the distribution of electric potential distribution in simple molecule models for the polymers after determining the configurations of orbital electron and proton. Furthermore the electron trap depth was calculated from difference between an electron affinity and conduction level for each polymers. As the model of polar polymers, Polycarbonate (PC), Polyethyleneterephthalate (PET), Polyethylenenaphthalate (PEN) and Polyimide (PI) are chosen. The relationships were also investigated on the simulated models of Polyethylene (PE), Polytetrafluoro-ethylene (PTFE), Polypropylene (PP) and Polystyrene (PS) as typical non-polar polymers. In the case of polar polymers, it is found that the electron traps were basically consisted of carbonyl group and benzene ring, and the trap depth equals to electron affinity which is always positive polarity. In the case of non-polar polymers, the conduction level equals to the electron affinity of PE and the trap depth equals to the difference between the conduction level and each electron affinity of polymer.

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Space Charge behavior in polyimide film under dc stress with visible light irradiation was studied using an improved measurement system of pulsed electro-acoustic (PEA) method. The PEA method has been widely used to observe a space charge distribution in various solid dielectric materials. We applied the method to investigate the interaction of visible light irradiation on space charge formation in dielectric materials under dc stress. It is well known that the conduction property in dielectric materials is sometimes affected by the light irradiation. The space charge formation is also said that it affects to the conduction current property in dielectrics. However the relationship between the space charge and the light irradiation haven't been clear yet. To observe the effect of the light irradiation on the space charge distribution in polyimide film, we measured the time dependent space charge distribution under dc stress with the irradiation of visible light from four kinds of LED light sources. From the results, it is found that the space charge is formed by the irradiation of light under dc stress, while it is not formed without the irradiation. Furthermore, it is also found that the charge distribution is strongly affected by the energy of the irradiated light.

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The forthcoming IEC 60060-1 mandatorily requires a curve fitting technique and FFT in determining impulse voltage waveform parameters. The digital recorder befitting to the technique is a multi-purpose type which is characterised by high sampling rate at the cost of vertical resolution. As a multi-purpose recorder, the linearity tests defined by IEC 61083-1 cannot be carried out by its manufacturer. It is users who have a responsibility of digital recorder's linearity. This is a clear contrast to the cases with a conventional exclusive recorder, whose linearity tests have indirectly been performed by the manufacturer. Authors completed a series of software packages which confirm if a given digital recorder fulfils linearity tests defined by IEC 61083-1. Four (two TDS5052, one TDS5052B and one TDS3052) multi-purpose digital recorders have been tested using the developed packages and it is confirmed that TDS3052, which has been used in the international comparative test, failed to satisfy the requirements in IEC 61083-1. The software developed by the initiative of Special Committee for Standardisation of High-Voltage Measurements is proposed to be distributed and used as Japan's standard.

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Dependence of initial oxygen concentration on ozone yield using streamer discharge reactor driven by an inductive energy storage system pulsed power generator is described in this paper. Fast recovery type diodes were employed as semiconductor opening switch to interrupt a circuit current within 100 ns. This rapid current change produced high-voltage short pulse between a secondary energy storage inductor. The repetitive high-voltage short pulse was applied to a 1 mm diameter center wire electrode placed in a cylindrical pulse corona reactor. The streamer discharge successfully occurred between the center wire electrode and an outer cylinder ground electrode of 2 cm inner diameter. The ozone was produced with the streamer discharge and increased with increasing pulse repetition rate. The ozone yield changed in proportion to initial oxygen concentration contained in the injected gas mixture at 800 ns forward pumping time of the current. However, the decrease of the ozone yield by decreasing oxygen concentration in the gas mixture at 180 ns forward pumping time of the current was lower than the decrease at 800 ns forward pumping time of the current. This dependence of the initial oxygen concentration on ozone yield at 180 ns forward pumping time is similar to that of dielectric barrier discharge reactor.

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Electrostatic precipitators are used in decontaminating polluted gases in expressway tunnels in order to improve both driver safety and the environment around tunnels. A conventional electrostatic precipitator has high collection efficiency. However, ESPs have the problem of re-entrainment. This problem occurs in the case of capturing carbon or other particles of low electrical resistance by an electrostatics precipitator. Unfortunately, carbon is the major component of DEPs. In this work, we discussed the method preventing particle re-entrainment, and devised applying trapezoid wave voltage to the collecting electrodes. DC voltage is applied to pre-charger. The collection efficiency of large particles decreases due to particle re-entrainment with DC high voltage applied to collecting section. However, when trapezoid wave voltage applied to the collecting section, the collection efficiency of large particles improves with increasing the frequency, or decreasing the changing ratio of trapezoid wave voltage.

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The virtual reality (VR) is one in the intelligence information communications technologies. As the application to the education field of VR, we construct a support system for the penmanship using the haptic display. We evaluated the first impression.

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