• Transactions of the Korean hydrogen and new energy society
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• v.5 no.1
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• pp.1-8
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• 1994

Lattice structure, hydrogen absorption characteristics, discharge capacity and cycle life of $V_{22}Ti_{16}Zr_{16}Ni_{39}X_7$(X= Cr, Co, Fe, Mn, Al) alloys were investigated. The matrix phases of these alloys were the C14 Laves phase. Chromium-containing alloy had a vanadium-rich phase in addition to the Laves phase. The chromium, maganese, or aluminum-containing alloys had lower hydrogen equilibrium pressure and larger hydrogen absorption content than the cobalt or iron-containing alloys. The discharge capacities of these alloys were 270~330mAh/g. The discharge capacity according to the alloying element X decreased in the order of Mn>Cr>Co, Al)Fe. The charge/discharge cycle lives of the chromium, cobalt or iron-containing alloys were longer than those of maganese or aluminum-containing alloys due to the lower vanadium dissolution rate.

• Journal of Environmental Science International
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• v.20 no.8
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• pp.1049-1059
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• 2011

This paper examines the effects of the partial solar eclipse of 22 July 2009 across the Korean peninsular on surface temperature and ozone concentrations in over the Busan metropolitan region (BMR). The observed data in the BMR demonstrated that the solar eclipse phenomenon clearly affects the surface ozone concentration as well as the air temperature. The decrease in temperature ranging from 1.2 to $5.4^{\circ}C$ was observed at 11 meteorological sites during the eclipse as a consequence of the solar radiation decrease. A large temperature drop exceeding $4^{\circ}C$ was observed at most area (8 sites) of the BMR. Significant ozone drop (18~29 ppb) was also observed during the eclipse mainly due to the decreased efficiency of the photochemical ozone formation. The ozone concentration started to decrease at approximately 1 to 2 hours after the event and reached its minimum value for a half hour to 2 hours after maximum eclipse. The rate of ozone fall ranged between 0.18 and 0.49 ppb/min. The comparison between ozone measurements and the expected values derived from the fitted curve analysis showed that the maximum drop in ozone concentrations occurred at noon or 1 PM and was pronounced at industrial areas.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1528-1535
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• 2009

Characteristics of R-22 and R-134a two-phase vaporization in horizontal small tubes were investigated experimentally. In order to obtain the local heat transfer coefficients, the test was ran under heat flux range of 10 to $40\;kW/m^2$, mass flux range of 200 to $600\;kg/m^2s$, saturation temperature range of 5 to $10^{\circ}C$, and quality up to 1.0. The test section, which was made of stainless steel tube and heated uniformly by applying an electric current to the tube directly, have inner tube diameters of 0.5, 1.5 and 3.0 mm, and lengths of 0.33 and 2.0 m. The effects on heat transfer coefficient of mass flux, heat flux and inner tube diameter were presented. The experimental heat transfer coefficients were compared with the predictions using existing heat transfer coefficient correlations. A new boiling heat transfer coefficient correlation based on the superposition model, with considering the laminar flow, was developed.

• Review of KIISC
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• v.22 no.8
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• pp.7-14
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• 2012

이메일 스팸메일의 대부분은 악성코드에 감염된 좀비PC에 의해 발송된다. '11년 시만텍 보고서에 따르면 한국발 좀비PC에 의한 스팸메일 발송이 세계 1위를 차지했으며, '12년에도 상위수준을 유지하고 있다. 본 논문에서는 이메일의 패턴 분석을 통해 좀비PC 및 같은 공격명령을 받은 봇넷그룹을 자동으로 탐지하는 시스템을 개발하고, 이를 통해 산출된 다양한 데이터에 대한 분석결과를 제시한다. 좀비PC 및 봇넷그룹 탐지결과는 스팸메일 차단기술로 활용 가능할 뿐 아니라, 악성코드 유포동향 파악 등 다양한 목적의 분석에 활용 가능하다.

• Communications for Statistical Applications and Methods
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• v.21 no.1
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• pp.11-22
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• 2014

In this study, we propose a simultaneous test procedure based on the individual - values for each sub-null hypothesis with several well-known combining functions. We then compare the efficiency of our procedure with existing tests by obtaining empirical powers through a simulation study. Finally, we discuss some interesting features related to simultaneous test and point out a misconduct for the simulation study published in the previous work.

• The Korea Journal of Herbology
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• v.22 no.2
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• pp.79-82
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• 2007

A headache due to retention of phlegm has vomitting, dizziness, nausea, etc. A headache due to retention of phlegm mainly was occurred by insufficiency of the spleen and stomach. Banhabaekchulcheonmatang(半夏白朮天麻湯) has effects of strengthening the spleen and reducing phlegm and calming the endopathic Wind relieving fainting. I prescribed the Banhabaekchulcheonmatang(半夏白朮天麻湯) to a patient with headache due to retention of phlegm. After taking these medicines, the patient was cured.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.6 s.183
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• pp.22-28
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• 2006

• Review of KIISC
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• v.22 no.2
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• pp.7-14
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• 2012

사이버보안 위협의 양상이 점차 세계화되고 피해의 규모가 날로 심각해지고 있어, 한 지역이나 한 국가만의 노력으로는 사이버공간의 안전성을 보장하기에는 한계가 있다. 이러한 사이버 공간에서의 보안 문제 해결을 위한 국제적인 공조 대응 노력의 일환으로 사이버보안 정보공유 기술이 등장하였다, 본 고에서는 사이버보안 정보교환 기술의 개발 동향에 대해 간단히 소개하고, 국제표준화단체인 ITU-T SG17을 중심으로 사이버보안 정보 교환 기술에 대한 국제 표준화 동향을 살펴본다.

• The Optical Journal
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• s.121
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• pp.20-22
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• 2009

현재 미국, 유럽, 일본 등에서 III-V 화합물 반도체 태양전지 시스템에 대한 활발한 연구 및 상용화가 진행중이다. 국내에서는 그동안 III-V 화합물 반도체 분야의 투자가 매우 제한적으로만 있어 왔고 그 중에서도 특히 화합물 반도체 태양전지의 투자는 거의 없었다. 최근 들어 KIST, KANC, 아주대, 전북대, ETRI, KOPTI, KETI 등에서 III-V 화합물 반도체 태양전지 연구가 새로 시작되었다. KIST에서는 현재 월광모듈도 개발 중이다.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.678_679
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• 2009

본 연구에서는 ETC용 소형 BLDC 모터에서 소음, 진동의 원인인 Cogging 현상을 줄이기 위한 목적으로 Core 형상에 따른 Cogging 현상에 대한 연구를 진행하였으며, 이 중, 고정자 Core에 Arc-type 의 sub slot을 적용하여 정격 토크 대비 22.23%에서 4.71%로 코깅 토크를 낮추었다.