• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2005년도 하계학술대회
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• pp.74-84
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• 2005

In this paper, a new coexistence mechanism between IEEE 802.15.4 and IEEE 802.11, ACROS (Active Channel Reservation for coexistence), is proposed. The key idea of ACROS is to reserve the channel for IEEE 802.15.4 transmission. During the reservation, IEEE 802.11 transmissions cannot be occurred. Request-to-send/clear-to-send mechanism of IEEE 802.11 is used to reserve channel. The proposed ACROS mechanism is implemented into PC based prototype. By the experiments, the $e{\pm}ciency$ of ACROS is proved.

• 한국대기환경학회지
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• 제24권5호
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• pp.574-583
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• 2008

The results of HAPs emission data using TRI (Toxic Release Inventory), SODAM (Source Data Management system) were investigated and the emissions of 7 heavy metals from their sources and emission processes were also analyzed. Questionnaire for source data analysis as well as the stack sampling were carried out for 17 factories among 6 selected industrial types. The annual amount of emissions was estimated based on the measured concentration and flow rates. All sources were operated with high efficiency control devices and the concentration levels of all heavy metals were shown to be below 0.1 to of regulation standard. The highest emission source of heavy metals was steel manufacturing industry with the annual emission of 342.9 kg/yr and followed by hazardous waste incinerator, paint manufacturing, nonferrous metal manufacturing, rolling & press goods manufacturing and storage battery manufacturing. In the case of Hg, the emissions were quite significant from electric acros of steel manufacturing industry, although the concentration level was below the emission standard, showing the necessity of specific care for its management.