• Proceedings of the Korea Information Processing Society Conference
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• 2015.10a
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• pp.883-886
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• 2015

최근 헬쓰케어 장비나 웨어러블 컴퓨터 등에 대한 연구가 활발하게 진행되고 있으며, 유비쿼터스 헬스케어 환경은 이러한 다양한 센서와 휴대용 의료 장치들에 의해 구성된다. PAN은 인간 주변의 디바이스들을 무선으로 연결하여 하나의 네트워크를 구성하는 핵심 기술로서, 차세대 무선 네트워크로 주목을 받고 있다. 본 논문에서는 안전한 u-헬스케어 서비스를 위한 PAN 환경을 정의하고, 발생 가능한 보안 요구사항을 도출한다. 그리고 이를 기반으로 개인 건강 정보를 보호하기 위한 보안프레임워크를 정의한다. 마지막으로 PAN의 이종(異種) 네트워크 환경을 고려한 새로운 보안 프로토콜을 제안한다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.5
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• pp.21-27
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• 2008

Ubiquitous environments make it possible to connect people and objects together seamlessly using networking technology. To realize ubiquitous environments many kinds of devices should follow the exact protocol. To observe protocol and prepare the increasing network traffic are very difficult in the aspects of maintenance, so the new efficient technology is required. Wimedia technology is a prominent ubiquitous technology which can make connection with many devices. This paper propose a energy efficient method for Wimedia bridge implementation which is a part of scale-free uPAN systems. The proposed method can reduce network expenses which is generated by protocol requirements by adding efficient packet encapsulation and bridging technology. It can be proved to be more time and energy efficient by simulations.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.183-183
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• 2017

Pan evaporation (Epan) is an important indicator of water and energy balance. Despite global warming, decreasing annual Epan has been reported across different continents over last decades, which is claimed as pan evaporation paradox. However, such trend is not necessarily found in seasonal data because the level of contributions on Epan vary among meteorological components. This study investigates long-term trend in seasonal pan evaporation from 1908 to 2016 across South Korea. Meteorological variables including air temperature (Tair), wind speed (U), vapor pressure deficit (VPD), and solar radiation (Rs) are selected to quantify the effects of individual contributing factor to Epan. We found overall decreasing trend in Epan, which agrees with earlier studies. However, mixed tendencies between seasons due to variation of dominant factor contributing Epan were found. We also evaluated the reference evapotranspiration based on Penman-Monteith method and compared this with Epan to better understand the physics behind the evaporation paradox.

• Proceedings of the Microbiological Society of Korea Conference
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• 1999.04a
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• pp.56.2-56.2
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• 1999

• TTA Journal
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• s.103
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• pp.191-194
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• 2006

• Proceedings of the Korean Fiber Society Conference
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• 1991.06a
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• pp.16-16
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• 1991

• 전기의세계
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• v.55 no.3
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• pp.20-24
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• 2006

• Rubber Technology
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• v.2 no.1
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• pp.17-25
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• 2001

• Textile Coloration and Finishing
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• v.15 no.3
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• pp.127-131
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• 2003

Acrylonitrile(AN) was solution-polymerized in dimethyl sulfoxide(DMSO) and tertiary butyl alcohol(TBA) at 30, 40, $50^\circ{C}$ using a low temperature initiator, 2,2'-azobis(2,4-dimethylvaleronitrile) (ADMVN). The low temperature polymerization using ADMVN, DMSO, and TBA is to be successful in obtaining high molecular weight polyacrylonitrile(PAN) with less branches by solution polymerization. Throug a polymerization of AN in DMSO at $30^\circ{C}$, PAN having viscosity-average molecular weight$(M_v)$ of 931,000 was obtained. And then, during AN solution polymerization in DMSO and TBA using a cosolvent system the in-situ formation of microfibrillar structure has been discovered at the cosolvent composition of 24/1$(V_{DMSO}/V_{TBA})$. The simultaneous process of gelation and phase separation of long chain molecules may explain the in-situ formation of PAN fibers during polymerization.

• Proceedings of the KSMRM Conference
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• 2007.10a
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• pp.26-26
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• 2007