We designed new magnetic position sensor that consisted soft magnetic material, permanent magnet, and magnetic sensor. Our simulation showed that the sensor was sensitive to a particular manufacturing tolerance. We redesigned sensor structure to improve linearity of output and to scale back the influence of manufacturing tolerance. Therefore, our simulation showed that the sensor had high-linearity output and high-robustness for manufacturing tolerance.

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Radiated electric field from a solar cell module set on the ground plane has been studied experimentally and theoretically in order to clarify the antenna effect of the solar cell module. In experimental examination, the radiated electric field characteristics of the thin-film Si solar cell module were measured by using the semi-anechoic chamber including the ground plane. In theoretical examination, the solar cell was assumed as a conducting wire, which has limited electric conductivity. And the radiated electric field of a solar cell was analyzed by using the method of moment. In both examinations, the maximum value of electric field strength for every frequency was measured or calculated when the solar cell module was rotated by 360 degree. Consequently the calculation value agreed with the measurement one within 3dB at the whole frequency region from 30MHz to 300MHz. As the results, we confirmed the availability and the validity of the calculation method by assuming the solar cell module as the conducting wire in the semi-anechoic chamber with the ground plane.

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We numerically analyze the spectra from the ensembles of tabular Au nanostructures at the water silicon interface which exhibit enhanced absorption effects in the infrared range. In the experiment, the water absorption signal rapidly grows and evolves into an asymmetric shape as the Au nanostructure grows and becomes connected. We used the numerical simulation based on RCWA (Rigorous coupled wave analysis) method to simulate this feature. In the simulated reflection spectrum of the O-H stretching mode at 3400cm^-1 (3μm), Fano shape appears as in the case of the experiment and we could reproduce this feature near the percolation threshold of the Au particle film.

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The paper deals with the problem of estimating the influence of truncation error in case of asynchronous sampling of the ac signal in the presence of subharmonics and interharmonics. The analysis makes use of the most general model of the voltage and current signal, i.e. the most complex spectral content that can be expected to appear in practice. In this paper, different processing methods are compared end equations derived for worst-case errors. A simulations and experimental check of the suggested procedure have been done as well. On the base of the derived relation it is possible to select, the best processing method and select the necessary number of samples in case of such a complex signal. The paper investigates the errors related to the proposed processing method, and provides estimation of truncation affect.

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TiO₂ deposition-methods are versatile and are expected to be more simple and easy, however, in recent years the industrial photocatalytic products have been developed enormously. In this work, photocatalytic TiO₂ micro-particles are deposited using the atmospheric pressure plasma jet device. Here, deposition-method is carried out in two steps, at first, the hydrolysis reaction time has been able to control which will resolve the TTIP coagulating trouble during the transportation, by acidifying the solution with AA (Acetic acid) and DEA (Diethanolamine). An experiment was performed to measure the hydrolysis reaction time of TTIP (Titanium tetraisopropoxide) solution by He-Ne laser. Secondly, the deposition of TiO₂ micro-particles was carried out using the atmospheric pressure plasma jet with the controlled TTIP solution in reaction time. Based on SEM and water contact angle measurement, it is found that the smaller the mixing ratios of TTIP and DEA the smaller the TiO₂ particle size. Also, the smaller the TiO₂ particles the smaller the contact angle under the UV irradiation which suffices the photocatalytic behavior.

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We research parallel microhollow cathode sustained (MCS) discharge plasma that is generated by parallel operations of the Microhollow cathode discharge (MHCD) plasma to produce a large volume atmospheric pressure plasma. We propose the cylindrical parallel MCS discharge plasma expecting electron supply by MHCD plasma and electron trapping effects of logarithm potential. Several MHCD electrodes are placed on cylindrical surface of 19 mm in radius and a thin wire is placed at a cylinder center axis. MHCD electrodes are supplied repetitive pulse voltage and the central wire anode is supplied DC voltage. So far, 8 parallel MCS discharge plasmas could be generated at 50 kPa. In this paper, the relationship between axial distance of MHCD electrodes and number of parallel discharge electrodes, and the condition to increase power supplied to MCS discharge were studied. Axial distance of MHCD electrodes were arranged to 6 mm and 16 parallel cylindrical MCS discharge in atmospheric pressure was generated. Power supplied to MCS discharge could be increased without decreasing number of parallel discharge electrodes by reducing current limiting resistor and shortening MHCD pulse width.

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An electron beam is widely used for various purposes in industry. We have developed a pulsed secondary electron emission gun (SEEG) which uses pulsed discharge and high voltage technology. The device has some inherent advantages, such as compactness in size and generation of a uniform and wide electron beam. The SEEG consists of a wire ion plasma source, a cathode plate in a vacuum chamber and an electron beam irradiation part. In this paper, we improved the SEEG for stable operation. Previously an abnormal electrical discharge in the vacuum chamber disturbed prolonged electron beam irradiation. Therefore, based on the simulation result of an electrical potential distribution, we installed a plate of reducing electric stress in the vacuum chamber. Then the stable operation of the SEEG became possible. In addition, we have conducted experiment on decomposition of toluene using the SEEG in N₂ and Air. The decomposition rate in N₂ was higher than that in air. The addition of O₂ and increase of humidity in N₂ decreased the decomposition rate. Reaction products such as benzene and xylene were identified in N₂ by means of GC-MS. On the other hand, benzaldehyde and formic acid were identified in Air. It is conceivable that the difference of byproducts is caused by the presence or absence of OH radical.

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Three-dimensional (3-D) localized magnetic reconnection was studied experimentally using torus plasma merging device TS-4. The direct measurements of 3-D structures of current sheet revealed two unsteady and fast reconnection mechanisms: 3-D deformation of current sheet and mass ejection. When strong compression force I_Acc∼60kA was applied to two plasma toroids with low guide field B_t/B_¦¦∼1, toroidal modes n=1-3 of current sheet were observed to grow only during their reconnection and to disappear after the reconnection. This 3-D deformation promoted mass ejection from the current sheet, increasing the reconnection rate as well as reconnection (toroidal) electric field and outflow. On the other hand, the reconnection rate was maintained low under the high guide field B_t/B_¦¦∼7 and weak compression I_Acc∼0kA. These phenomena suggest that local compression of current sheet triggers its strong dissipation as well as plasma mass ejection, which are responsible for the onset of 3-D localized reconnection.

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The novel cost effective 2-D ion temperature measurement system was developed by use of tomographic reconstruction of 35 line-integrated spectrums on five toroidal plane. Those 5×7 signals were measured by a polychromator with 35 optical fibers and ICCD camera and were transformed into local line-spectrum on the r-z plane by means of the Abel inversion at each wavelength. The 2-D(r-z) profile of ion temperature on r-z plane was finally calculated from the Gaussian fitting for the local spectrums.

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