• Journal of Advanced Marine Engineering and Technology
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• v.38 no.6
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• pp.730-736
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• 2014

Test standards for electrical and electronic equipment required for ship operations is applying the IEC-60533 standard. However, although a test procedure and a specified regulation are clearly defined in the deck and bridge zone and general power distribution zone, they are not regulated in the special power distribution zone with ship propulsion system. For these reasons, the costs for additional research and development have been invested. In this paper, we was measured power noise in a special power distribution zone in ship and we were compared and analyzed values measured. The actual experiments are performed on the ship of Korea Maritime and Ocean University. As a result, the acquired data on Hanbada shows that loop antenna with low frequency band(160kHz) and ultra log antenna with high frequency band(1.97GHz)occur about 6-8dB differences and about 8.7 difference respectively. Also, the acquired data on Hannara shows that each loop antenna of 1MHz, 11MHz, and 25MHz occurs about 7dB difference about 4-5dB differences respectively. so standard of Special distribution zone must be specified by comparative analysis of data obtained by the experiment more.

• Journal of Environmental Impact Assessment
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• v.27 no.2
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• pp.152-169
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• 2018

The purpose of this study was to analyze the effect of adjacentroads on the concentration of negative air ions in urban neighborhood park. The measured factors were negative air ion concentration, positive airion concentration, airtemperature,relative humidity, wind speed, green formation volume factor (GVZ) and distance from highway and general road. The mean negative air ion concentration was $206ea/cm^3$ and the positive air ion concentration was $416ea/cm^3$ in the influence zone of roads. On the other hand, the mean negative air ion was $339ea/cm^3$ and the positive air ion was $229ea/cm^3$ in the unaffected zone of roads, which are inner areas of the park. The difference of the negative air ion concentration according to the influence of the road was statistically significant. The negative air ion concentration model was presented by integrating the correlation analysis with the influence factors, and the explanatory power of the model was increased by adding the influence factor of the road.