In this paper, we propose an electric circuit e-learning system using LMS in Moodle. The proposed system allows lecturer to make problems without any programming skill by using graphical tools and numerical value inputs. In addition, the proposed system has a function of learning management by Moodle. Thus, lecturer can use the function of Moodle in learning management.

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The WHO (World Health Organization) recommended the necessity of electromagnetic (EM) dosimetry evaluation for pregnant women with fetus and children as one of the most primary research subjects in 2006, which has promoted the studies on whole-body-average specific absorption rates (WBA-SARs) in various kinds of numerical pregnant woman and child models with respect to safety limits of WBA-SARs. For the present safety limits, however, they are being determined in view of the behavior destruction of health adult animals for radio-frequency EM exposure and EM absorption characteristics at resonant frequencies, which are not based on experiments for pregnant and young animals. In this paper, we calculated the voxel SARs and WBA-SARs in anatomical detailed models developed for a pregnant woman and a 3-years child at their resonant frequencies. The histograms and cumulative relative distributions of voxel SARs were also derived to determine the statistical outlier in voxel SARs for pregnant woman and 3-years child models. As a result, we found that the mean voxel SARs agree with the WBA-SARs, and that the medians of voxel SARs in the pregnant woman and 3-years child models are 47% and 55% of their means, respectively, while their peak voxel SARs are 70 times larger than both of the means. This suggests a possibility that the FDTD calculated WBA-SARs could be overestimated due to the existence of statistical outliers. It was also found that although the total number ratio of voxel SARs for the outliers is 0.36% for the pregnant woman model and 0.34% for the 3-years child model, WBA-SARs except for these outliers are less than those in the pregnant woman and 3-years child models by 6.8% and 5.7%, respectively.

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Previously, we presented the results of experiment on the decolorization of the humate solution, which is one of the persistent substances utilizing the pulsed discharge in bubbles. In this paper, we describe experimental results and discussions on the decolorization of humate solution by ozone bubbling and ultraviolet (UV) irradiation.
A silent discharge type ozone generator and low pressure mercury lamps are provided in this study. Ozone concentration is varied with applied voltage across the both electrodes in the ozone generator which has a concentric cylinder electrode. Two kinds of low pressure mercury lamps of which the shortest wave length of light emission are limited at 180nm, and 200nm are prepared as UV source. The absorbance, pH and total carbon concentration in the humate solution are measured by a spectrophotometer, a pH meter and a total organic carbon analyzer. From the results, the temporal variations of absorbance and total carbon concentration in humate solution are observed after the ozone bubbling and ultraviolet irradiation. It is clarified that the variation of absorbance in humate solution by ozone bubbling is effective and UV in shorter than 200nm wavelength is remarkable to decolorize the humate solution.

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Two-dimensional magnetostriction of electrical steel sheet (Non-oriented and Grain-oriented) under high magnetic flux conditions was measured by a new method for evaluating magnetostriction phenomena in arbitrary direction. We made clear the various parameters of two-dimensional magnetostriction depending on the maximum magnetic flux density and inclination angle in detail. The validity of measurement results was reported by using the magnetostriction theory.

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A highly sensitive room temperature hydrogen sensor based on Fe-doped and undoped SnO₂ films were fabricated by the photochemical deposition. For deposition of doped and undoped SnO₂ films, a small amount of an aqueous solution was dropped on a glass substrate and irradiated by UV light. Pd was doped to the surface of the SnO₂ thin films by a photochemical technique, and then the samples were annealed. Response of a portable-type hydrogen detector consisting of the sample and a pocket tester was investigated. The Fe-doped sample showed higher sensitivity compared with the undoped sample.

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In this study, long term degradation test of MEA (membrane electrode assembly) which have different amount of catalysts in anode and cathode were performed using a CV method. As the result, it was clearly understood the degradation of MEA can be controlled by changing the amount of catalysts in anode and cathode respectively.

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