Air pollution caused by gas emission of pollutants produced from a wide range of sources including coal, oil and gas burning power plants, diesel engines, paper mills, steel and chemical production plants must be reduced drastically and urgently, as mandated by recent worldwide nation legislation which recently are being reinforced increasingly by international agreements. Non-thermal plasma in which the mean energy of electrons is substantially higher than that of the gas offer advantages in reducing energy required to remove the pollutants. The electrical energy supplied into the discharge is used preferentially to create energetic electrons which are then used to produce radicals by dissociation and ionization of the carrier gas in which the pollutants are present. These radicals are used to decompose the pollutants. There are two technologically promising techniques for generating non-thermal plasmas in atmospheric gas pressure containing the pollutants, namely electron beam irradiation and electrical discharge techniques. Both techniques are undergoing intensive and continuous development worldwide. This is done to reduce the energy requirement for pollutant removal, and therefore the associated cost, as well as to obtain a better understanding of the physical and chemical processes involved in reducing the pollutants. In the present paper only electrical discharge techniques for NOx removal from flue gases and exhaust emissions are reviewed. This paper summarizes the chemical reactions responsible for the removal of the major polluting constituents of NO and NO₂ encountered in the flue gases.

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Numerical simulators for electromagnetic field analysis are useful in development of wireless communication devices, dosimetry of radio frequency electromagnetic fields exposure, etc. Most of numerical simulators consist of preprocessor, postprocessor, and calculation kernel. Modeling of simulation and grid generation are made in the preprocessor. Numerical results are visualized and analyzed in the postprocessor. Electromagnetic field analysis is performed in the calculation kernel. Outlines of two methods, which are finite difference time domain (FDTD) method and moment method, frequently used in calculation kernels are introduced. In this article, examples of package simulator, in which FDTD method and moment methods are used, are shown.

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Difference of contact voltages between the electrodes and the human body causes a measurement error in measuring DC biomedical signals. It was unable to measure DC signals using the capacitive electrode because lower cut-off characteristics are formed by the capacitance of the electrode. The authors reported a modulation type of capacitive electrode using variable capacitance modulation to measure DC biomedical signals in the previous paper. However, the AC current for exciting the modulation capacitances on the electrode must be fed into the body, when the electrode is used.
  We propose a new modulation type of capacitive electrode that does not need to apply the AC current to the body. The signal voltage is applied on the modulation capacitances of the electrode through the input coupling capacitance of the electrode. Since the modulation capacitances have a nonlinear relationship between the applied voltage and the electric charge, modulated output voltage due to the signal voltage is produced by the modulation capacitances. This paper describes behavior of the new modulation type of capacitive electrode, and some experiments on the electrode. As a result, it is suggested that the electrode can measure DC biomedical signals of more than 1mV.

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In this paper signal processing by aspectum was applied to actual waveforms for the first time. Aspectum is the quantity to estimate the instantaneous power on the theory of natural observation method, which was proposed by Iijima. It can quantitatively evaluate the instantaneous power of signals. To begin with, the characteristics of aspectum was clearly shown by applying it to known model signals. And the analysis result of observed electromagnetic field signals radiated by lightning discharge was shown as a sample applying aspectum to actual waveforms.

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In this paper, we describe the method to estimate the damaged area of nerve fiber by neural magnetic stimulation. We have shown that the threshold for the nerve excitation become lowest when the junction of the figure-of-eight coil is parallel to the nerve fiber. The properties of nerve excitation in neural magnetic stimulation with a figure-of-eight coil are calculated with simulation. The spatial distribution of properties of nerve excitation is analyzed. The middle point of two points which the value of threshold for nerve excitation is a minimum is estimated as the terminal point. The running direction of the nerve fiber is also estimated by an angle between the coil axis and the tangent line which consist of points of two figure-of-eight coils.

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The behavior of peripheral nerves is worth measuring not only to understand our nervous system, but also to diagnose various neural malfunctions. SQUID seems to provide a new noninvasive method to monitor the activity or condition of peripheral nerves by measuring magnetic fields. This method seems to have an advantage of depth positioning of current sources over measuring the skin potential. However, hitherto there are only a few reports that describe experimental researches on magnetic fields induced by peripheral nerves. As a model of the electric current sources that propagate along a peripheral nerve, a pair of current dipoles back to back is suggested, however, it seems there is no theoretical model that supports this hypothesis. Therefore, a study on a method to estimate two current dipoles from a distribution of magnetic field was carried out. The preceding experimental studies on measuring magnetic fields from peripheral nerves are concerned only to the normal component of the field, however measuring tangential component of the field is helpful to estimate the moments of dipoles and the path of a nerve. Therefore here, a procedure to estimate a pair of dipoles from a distribution of both normal and tangential component of a magnetic field is described.

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In 1977, Tagashira et al. reported that the center-of-mass drift velocity W_r of an electron swarm defined in Time-of-flight (TOF) takes larger value than the drift velocity W_v defined in Pulsed Townsend (PT) when ionization collisions take place. At the same time, they explained that the larger values of W_r is caused by the ionization generation of electrons at the front side of extending swarm due to higher mean energy. In this paper, a new definition of virtual drift velocity in configuration space W´_r defined in PT is proposed, and calculated data of drift velocities and related quantities such as ionization coefficients and ionization frequencies in Ar in a high E/N range are discussed comparing with Tagashira’s data.

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The effect of plasma elongation on the second-stable spherical tokamak (ST)was numerically studied using the experimentally measuredpressure and current profiles of ultra-high beta STs. The maximum beta of ST over 50% was obtained in the TS-3 ST/CT experimentby applying an external toroidal field to an FRC. It was found that the marginal beta for the ballooning instabilityincreased with the plasma elongation κ of ST. The elongated STs with κ > 2 have the magnetic shear (S) -- pressure gradient(α) profiles located in the second-stable regime for the ballooning mode andthe stability margin increased with κ. The close relation between the absolute minimum-B profile andthe second stability was documented. The effect of elongation on maximum beta was observed to saturatewhen κ exceeded 3, indicating that the optimized elongationfor high-beta STs are located around 2 < κ < 3.

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The electrohydrodynamical (EHD) liquid-jets induced by the mechanism in which is referred to as pure conduction pumping were investigated in isothermal weakly conducting liquids, HFC43-10 and HCFC123. The properties of liquid-jet (flow velocity, pumping pressure and flow pattern) were examined by using a grounded electrode with four different types against a pseudo-doughnut electrode under an applied dc voltage. These electrode systems gave rise to a powerful liquid-jet, but in working liquids used here, there was the effect of voltage polarity on the flow direction. In order to create a more effective liquid-jet with a high directivity, the special nozzle (which is referred to as conical nozzle in this paper) was used together with the electrode system. This nozzle can make a distinctive pattern (spiral structure) of jets emerging from the outlet of nozzle. In this paper, the spiral structure of liquid-jets has been analyzed using the basic equations of fluid mechanics.

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It is found from simulation study that electromagnetic wave absorbers made of composites of Ni-Zn ferrite and SiO₂ particles, which are mutually isolated each other in the continuous medium of Ni-Zn ferrite, show absorption in the frequency region both below and above 1GHz. The spray method is proposed to fabricate such composites in this study. The thin films of Ni-Zn ferrite can be coated on the surface of SiO₂ particles by the spray thin film deposition method. It is confirmed by XRD and the electromagnetic characteristics measurement. The measured complex permeability approached to the calculated result using the isolation model of SiO₂ particles in the Ni-Zn ferrite medium than using Lichtenecker’s logarithm mixed low.

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High efficiency white organic light emitting diodes (WOLED) have been expected for applications of lighting, illumination and back-light sources for LCD. Recently, since organic phosphors demonstrated very high electroluminescence (EL) quantum efficiency of ˜100%, high efficiency WOLED with the organic phosphors has been anticipated. In this study, we employed an emitter layer which is doped with blue and red phosphorescence molecules. In our optimized device structure, we obtained maximum EL quantum efficiency of 4%. However, the shapes of the EL spectrum were strongly dependent on current density. With analysis of exciton decay process under optical and electrical excitations, we conclude that triplet-triplet annihilation occurs in blue and red phosphors independently, resulted in a significant change of the EL spectrum. Thus, the coincidence of the lifetimes of the blue and red phosphors is indispensable to escape change of EL spectrum with current density.

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Since bulk high T_c superconductor (HTS) characteristics are not homogeneous in some specimens due to grain boundaries and cracks, magnetic characteristics should be assessed under the static and AC magnetic field. Thus static magnetic characteristics of the HTS have been evaluated by measurements of the magnetic flux density on the specimen surface using a hall element and numerical analyses using a finite element method. AC magnetic characteristics have been experimentally evaluated by measurements of the magnetic field using a hall element and pick up coils.
  In this research, AC magnetic characteristics of HTS are evaluated by numerical analyses using a three-dimensional finite element method. Critical current densities of the HTS under various external magnetic field strength are estimated by analysis and experiment results. Moreover, the heat generation of the superconductor is considered.

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Partial discharge and surface discharge may occur around stator end-winding of rotating machine owing to convergent field caused by geometric configuration. In order to suppress such field, the material having nonlinear voltage - current characteristics such as SiC is painted or taped on the end-winding. This paper describes potential distribution around the end-winding of rotating machine using EMTP (Electromagnetic Transients Program) assuming RC lumped constant circuit for overvoltage tests and in operation. The result showed that painting SiC reduces the electric field along the surface due to the nonlinear resistivity. The maximum electric fields are found to exist at the point where the potential difference between neighboring coils has a maximum. As a result, the maximum field occurs at the end of SiC layer for overvoltage tests, and in the region where potential becomes almost constant after potential grading by SiC layer in operation of rotating machine. Distance difference dependence at the end of SiC layer between neighboring coils for maximum field are also discussed. The maximum field increases with the distance so that the electric field may reach the critical field of air.

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A magnetic force control device using laminate composite of magnetostrictive and piezoelectric materials is proposed. This magnetic force control is based on the inverse magnetostrictive effect, whereby the variation of the magnetization in the magnetostrictive material changed with an applied voltage on the piezoelectric material is converted to that of a magnetic force via magnetic circuit. Due to the capacitive property of the piezoelectric material, the device requires little electric energy to maintain constant force. Furthermore, the device is easy to assemble compared with our proposing conventional device. In this paper, the static characteristics, voltage vs. magnetic force, energy conversion ratio and power consumption are investigated. The calculation of the magnetic force combining a FEM and equivalent magnetic circuit analysis is verified.

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The electrostatic powder coating using a tribochager has a serious problem; it is hard to electrify some kinds of powder paints sufficiently. To solve this problem, plasma treatment in atmospheric pressure was carried out. The plasma was generated by superimposing surface and barrier discharges (SSBD). As a result, the effect of SSBD was greater than the sum of effect of surface discharge (SD) and that of barrier discharge (BD). It is thought that the effect related not only with discharge power but also with the other factors. Dust collection effect of BD is possibility one of the factors.

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Pulsed electroacoustic (PEA) method has been widely used to observe space charge in dielectrics. The ordinary PEA unit sandwiches a specimen for applying the pulsed electric field. There have been long awaited demands to monitor space charge profiles under electron beam or radioactive rays irradiations, as well as to observe space charge behaviour during plasma processing. This paper proposes a new PEA system without a top electrode unit. The new system can measure internal space charge profiles without covering irradiation surface of specimens.

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