• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.289-292
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• 1995

In this experiment the specimen is selected for epoxy resin used in the molding compound materials for the power semiconductors. The specimen was divided into the two parts. one is a specimen without irradiation, the other is irradiated with electron beam, of which dose is 1[Mrad], 2[Mrad], 4[Mrad], 8[Mrad] and 24[Mrad], respectively. From the analysis for the physical properties of the specimen, the carbonyl group which is asffact the electrical properties is decreased according to increase the dose of the electron beam. In the measurement of dielectric characteristics among the electrical properties, the frequency dependance of the dielectric characteristics is confirmed that its ${\beta}$-peak is represented by one peak due to attribute to the main chain below 50[$^{\circ}C$], and two peak above the temperature 100[$^{\circ}C$].

• Journal of Aquaculture
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• v.15 no.2
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• pp.119-121
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• 2002

A study on the acute toxicity in the Nile tilapia, Oreochromis niloticus fry showed that the 24hr-$LC_{50}$ was 18.6% for NaCl,152 ppm for formaline and 2.1 ppm for $KMnO_4$. The fry responded to narrow range of concentration of all the tested chemicals and their toxic effects were dose-dependent.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1126-1128
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• 1995

In order to investigate the electrical properties for transformer oils due to electron bean irradition, the dielectric properties was made researches by dose of irradition To measure the dielectric loss of irradiated specimen, coaxial cylindrical liquid electrode was used, geometric capacitance was confirmed to 16[pF]. Experiments for measuring the dielectric loss were performed at $20{\sim}120[^{\circ}C]$ in temperature range, $30{\sim}1.5{\times}10^5$[Hz] in frequency range and $300{\sim}1500$[mV] in voltage range and then, the result of experiment for the movement of carrier and the physical constants to contribute dielectric properties of specimen due to electron beam irradiation introduced.