• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.599-602
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• 2008

본 논문에서는 증명프로토콜(EAP)을 분석하는 것에 중점을 두고 있다. 무선네트워크 환경에서 안전하게 통신하기 위해 사용되는 EAP 방법을 검토하여 그 방법들의 이점과 취약점을 분석하며, 새로운 프로토콜을 제안한다. 제안된 프로토콜은 무선 네트워크인 802.11에 맞추어 설계하였다. 그리고 802.11 환경이 아닌 다른 무선 네트워크 환경인 RFID와 WiMAX 환경에서 EAP가 가져야 하는 특징을 제시하며 3G네트워크 환경에서 가져야 할 새로운 특징을 제안한다.

• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.3 s.22
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• pp.69-76
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• 2006

An hydraulic and hydrologic analysis procedure was proposed to reduce the inundation damage of highway in urban stream, that could contribute the EAP and Traffic control planning of Dongbu highway in the Jungrang stream basin which is one of the representative urban area in Korea. We performed the HEC-HMS runoff analysis, and the UNET unsteady flow modeling to decide the inundation reaches and their characteristics. The high inundation risk areas were of Emoon railway bridge and the Wollueng bridge, which are inundated in the case of 10 year and 20 year frequency flood respectively. We also analyze the inundation characteristics under the various conditions of the accumulation rainfall and the duration. Flood elevation at the Wolgye-1 bridge exceed over Risk Flood Water Level(EL.17.84 m) when the accumulation rainfall is over 250 mm and shorter duration than 7 hr. When neglecting backwater effect from the Han river, inundation risk are highly at the reach C2(Wolgye-1 br. ${\sim}$Jungrang br., left bank), C1(Wolgye-1 br. ${\sim}$Jungrang br., right bank), D(Jungrang br. ${\sim}$Gunja br.) in order, but when consider the effect, the inundation risk are higher than the others at the reach D2(Jungrang br. ${\sim}$Gunja br., left bank) and E(Gunja br. ${\sim}$Yongbi br.), which are located downstream near confluence.

• Magazine of the Korean Society of Agricultural Engineers
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• v.53 no.4
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• pp.2-13
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• 2011

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.660-666
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• 2001

The Ionic Polymer Metal Composite (IPMC) is one of the electroactive polymer (EAP) have potential application as micro actuators. In this study, IPMC is used as actuator to control of the direction for the endscopic microcapsule. Because it bends in water and wet conditions by applying a low voltage $(1\sim3\;V)$ to its surfaces. The basic characteristics and the static modeling of IPMC are discussed. Also the dynamic modeling is performed using the Lagrange' equation. Computer simulation results show that the performed modeling guarantee similarity of actual system.

• Korean Journal of Microbiology
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• v.34 no.3
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• pp.101-107
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• 1998

Biological treatment of Arabian light crude oil-contaminated pebble was investigated in laboratory microcosms after supplementation with inorganic nutrients and oil-degrading microorganisms. Glass columns ($10cm{\times}20cm$) were used as microcosms and each microcosm was filled with pebbles of diameter less than 40 mm. After initial oil contamination of 2.4% (w/v), Inipol EAP-22 or slow release fertilizer (SRF) was added as inorganic nutrients and microorganisms were sprayed over pebbles. When $C_{17}$/pristane and $C_{18}$/phytane ratios were used as a marker for oil biodegradation, both ratios for microcosm supplemented with SRF and microorganisms were the lowest (below detectable range) after 92 days. Elimination of oil by abiotic processes, however, were minimal with decrease of $C_{17}$/pristane and $C_{18}$/phytane ratios from 3.55 and 2.41 to 3.06 and 1.50, respectively. The numbers of heterotrophic and oil-degrading microorganisms, and biological activity (dehydrogenase activity) corresponded to the course of biodegradation activities in all microcosms. During the whole experimental period, there was no significant nutrient deficiency only in the microcosm with SRF and microorganisms. It seemed that a continuous supply of inorganic nutrients using SRF was the most important factor for the successful performance of biological treatment in oil-contaminated pebbles.

• Journal of Convergence for Information Technology
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• v.7 no.1
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• pp.1-9
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• 2017

This study is to verify the mediating effect of depression between job stress and job satisfaction among workers in small and medium sized enterprises. The survey was conducted to workers in small and medium sized enterprises, and 117 cases were finally applied. As results, job stress has significantly negative effect on job satisfaction and positive effect on depression. Depression also has partial mediating effect on between job stress and job satisfaction. We finally suggest that customized management system should be provided for the workers in small and medium-sized enterprises, and occupational welfare system, including employee assistance program (EAP), must be launched for these workers.