• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.381.1-381.1
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• 2016

분석 방법의 간편함과 용이함의 장점은 물론, 시료 전처리 과정이 적어 시료물질의 임의 파괴나 훼손을 방지한다는 이유에서 최근 10년 간 많은 연구가 이루어지고 있는 대기압 질량분석 기술은 기압차이가 없는 대기압 분위기에서 질량분석이 이루어지기 때문에 시료를 질량분석기 입구 바로 앞에 스테이지를 설치하고서 시료를 이온화하는 경우가 대부분이다. 이 때문에 균질하지 않은 시료의 관심 영역을 모니터링하면서 질량분석을 하기에는 어려움이 있으며, 공간 정보를 추가한 질량분석 이미징에 한계가 있었다. 이에 본 연구팀은 질량분석기 입구에 챔버와 보조 펌프를 장착하여 강제로 기체 흐름 일으켜 시료로부터 발생한 이온을 질량분석기 입구로 유도하여, 원거리에서 시료를 이온화해도 질량분석기 입구까지 이온을 성공적으로 전달시키는 방법을 제안한다. 이를 이용하면 분석하고자 하는 시료를 현미경 스테이지 위에 위치시켜 분석하고자하는 부분을 현미경으로 확인하면서 질량분석을 할 수 있으며, 나아가 대기압 질량 분석 이미징 기술을 구현할 수 있다. 대기압 탈착/이온화원은시료에 열적 손상이 없는 조건으로 시편의 이온화 및 탈착 과정이 이루어지게 하기 위해 저온 대기압 헬륨 플라즈마 젯과 펨토초 레이저를 결합하여 대기압 이온화원을 제작하였다. 이온 전달관은 1/4" (6.35 mm) 외경의 60 cm 길이의 스테인리스 스틸관을 사용하여 질량분석기에서 약 60 cm 떨어진 현미경 위의 시료의 질량분석이 가능하게 했다. 보조 펌프의 계기압과 저온 대기압 헬륨 플라즈마 젯의 헬륨 기체의 유속을 변화시키면서 시료인 PDMS (polydimethylsiloxane) 의 질량 스펙트럼 (m/z 270.314) 세기를 관찰하여 최적의 이온 전달 조건을 찾았다. 추가로 현미경 스테이지에 정밀 2-D 자동 스캐닝 스테이지를 장착하여 질량분석 정보에 공간 정보를 더할 수 있는 질량분석 이미징 기술 방법을 개발하여 생체 시편의 질량분석 이미징을 얻었다.

• Economic and Environmental Geology
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• v.29 no.3
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• pp.381-393
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• 1996

Cretaceous volcanics and volcaniclastic sediments are abundantly distributed in the Haenam area located at the tip of the southwestern part of the Yongdong-Kwangju depression zone. The Cretaceous strata correlated with the Yuchon Group of the Kyongsang Supergroup are divided into three formations: Hwawon Formation, Uhangri Formation and Haenam Formation in ascending order. The stratovolcanic Hwawon Formation is mainly composed of andesite and andesitic pyroclastics. The Uhangri Formation is the lacustrine sedimentary deposit. The Haenam Formation is composed of Hwangsan tuff, Haenam tuff, Yongdang tuff, Seoho tuff, and also Acidic lava, both being formed by a cogenetic acidic volcanism. The topographic circular structure of the Cretaceous strata was controlled by the doming of Jurassic Sani granite. Cretaceous volcanism in the study area is characterized by the two stages of intermediate volcanic activity in Cenomanian to Albian, and acidic volcanic activity in Campanian to Coniacian.

• Fire Science and Engineering
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• v.21 no.4
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• pp.44-51
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• 2007

Most of the Korea temples of cultural property are wooden buildings and easy combusted. They are often located in mountain area far away from the city. It is very difficult to approach the fight area. The putting out is very difficult in the initial fire time. And for protecting the cultural property in the long-term continuous fire source there are some restrictions in water source and suppression system. In this paper the initial putting out fire due to the forest fire and the protection of cultural property in the long-term continuous fire source were researched. The improved project about fire control facilities of the Korea cultural property was proposed. In the proposed project the facilities using Water mist which can reduce more loss than existing facilities using water are applied. In view of the topographic position the method of eliminating the energy of combustibles and wall for cutting off the heat in the fire control facilities are also mentioned.

• Fire Science and Engineering
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• v.20 no.4 s.64
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• pp.58-64
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• 2006

Smoke extraction in tunnel fire is investigated experimently with thermal model. The object is a immersed tunnel, of which the partial extraction system exists between the tubes. The model tunnel is measured 12 m long, 0.5 m wide and 0.35 m high. The fire is simulated to pool fire and the size corresponds to full scale fire of 5 MW based on Froude modeling. The performance of partial extraction system is determined under two ventilations, natural and longitudinal ones. The results show that compared with longitudinal ventilation, the smoke extraction efficiency of natural ventilation is increased about 30% because of smoke stratification in tunnel. Also the efficiency is identical to the iso-thermal model. The results will be help for activation of the ventilation system in emergency such as in the event of tunnel fires.

• Journal of the Korean Institute of Gas
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• v.25 no.6
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• pp.7-13
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• 2021

Various research has been done on fires and explosions at gas stations at home and abroad. However, only studies of off-site damage in the event of fire at the gas station were conducted, and research on fire at the auxiliary facilities in the gas station was insufficient. The gas station is a place where anyone can easily access dangerous goods. As the risk of fire increases due to the recent increase of auxiliary facilities such as convenience stores and car repair shops in gas stations, it is important to detect the effects of fire on the main oil refinery in case of fire and to verify the validity of existing regulations. In this thesis, we conducted a study to find out the effect of radiation heat on the separation between fixed and fixed oil reactors in the event of fire at an auxiliary facility. Simulation was modelled using FDS 5.5.3 Version, and the size of the fire source was configured with 13 fire assessment devices and the heat emission rate per unit area was entered. Simulation shows that the separation distance of 2 m does not secure the safety of the gas pump in the event of fire at the auxiliary facilities, and radiation heat does not damage at the separation distance of at least 4 m. Accordingly, facilities that can block radiant heat in the event of fire at auxiliary facilities, and measures to limit the use of auxiliary facilities or to re-impose the separation between buildings and fixtures will be needed.

• Tunnel and Underground Space
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• v.14 no.4
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• pp.269-274
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• 2004

In this study reduced-scale experiments were conducted to determine the backlayering distance in tunnel fires. The 1/20 scale experiments were carried out under the Froude scaling using ethanol square pool fire ranging from 8 to 1km in each side with total heat release rate from 2.47 to 12.30 ㎾. It has been found that ventilation velocity increases with aspect ratio(tunnel height/tunnel width). At L$\_$B/$\^$*/ ＜5 the ventilation velocity increases proportional to the backlayering distance from 0.25 power of the heat release rate. However at L$\_$B/$\^$*/ $\geq$5 the ventilation velocity varies as the 0.3 power of the heat release rate.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2000.09a
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• pp.30-36
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• 2000

목포해역에는 1981년과 1991년 및 1994년에 영산강하구언과 영암방조제 및 금호방조제가 각각 완공된 바 있으며, 이들 하구언과 방조제의 위치를 전반적인 목포해역의 형상과 수심도와 함께 Fig. 1에 도시하였다. Fig. 1에서 화원반도와 압해도 사이의 2개 섬으로 분리된 3개 수로를 남쪽부터 순차적으로 목포구, 중구, 북구라 하는데, 목포구의 단면이 월등히 커서 내측 수역과의 해수교환은 주로 목포구를 통해 이루어지며, 목포해역에서 목포구의 특별한 기능은 본문에서 여러 번 기술되고 있다. (중략)

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.298-301
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• 2011

본 연구에서는 지하 방호공간에서 화재가 발생한 경우 워터커튼 시스템에 의한 연기의 차단효과와 화재제어 특성을 분석하였다. 이를 위해서 분사각도 $180^{\circ}$, 오리피스 직경 8.2 mm의 노즐과 지하방호 공간용 실화재 실험 장치를 제작하였으며, 화재강도 1.5 MW 기준 A급 1단위 화재 실험으로부터 온도분포와 가시도를 측정하여 연기의 차단효과를 확인하였다. 화재제어 특성을 분석하기 위해서 NIST(National Institute of Standards and Technology)의 해석프로그램인 FDS(Fire Dynamic Simulator)를 사용하여 동일한 실험조건에서 온도분포를 비교하였으며 노즐의 설치개수 변화에 대한 화재해석 및 실험결과로부터 워터커튼 시스템은 노즐의 설치위치와 개수, 화원으로부터의 거리, 제연 등의 설비 조건과 분사 노즐의 특성, 공급 유량 등이 중요한 상관관계를 갖고 있음을 확인하였다.

• Journal of Navigation and Port Research
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• v.42 no.4
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• pp.283-290
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• 2018

Due to the environmental factors of the sea, ship accidents always contain an inclination angle. The change in the ship affects not only the evacuation speed of passengers but also the fire growth in the ship. For this reason, when analyzing the fire, it is necessary to analyze the risks by considering conditions of inclination. In this study, the temperature that affects the fire was calculated by alteration of ship's heel and trim angle and analyzed using FLUENT. Based on fire occurrence position, evacuation should be done within 37 seconds under the condition of $-10^{\circ}$ heeling angle and 36 seconds under the condition of $-10^{\circ}$ trim angle. However, it was predicted that the evacuation will not be affected under the conditions of $+10^{\circ}$ heel angle and $+10^{\circ}$ trim angle. For these reasons, it is confirmed that when the ship is on fire, evacuation measures should be considered based on the heel and trim conditions as per the location of the fire.

• Fire Science and Engineering
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• v.29 no.3
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• pp.1-5
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• 2015

The productivity and demand of porous material has been increasing by development of industry and increasing income. In particular, the fire caused by using wood flour risks wood processing industry and stock farm. The heat transfer of wood flour is carried into the depth direction by effect of oxidizer around flame, flame sometimes is progressed as smoldering. In the case of progressing as combustion fire, identifying the location of fire is difficult, and it leads to failing fire aid fire fighting. Therefore potential cause is acted as raising additional damage. This paper conducts experiments of downward deep seated fire of natural convection conditions. The samples is New Zealand wood flour that is demanded much in the domestic and oversea market. In this experiment, temperature of deep seated side is measure by changing wood flour density in holder The densities used in experiment are 3%, 5%, 10%, 15%. As a result, the tendency of temperature inside decreases as wood flour density increases. But, in the case of density which is above $0.2140g/cm^3$, the phenomenon, decreasing temperature, is not shown. The result of measurement show that average flame spread speed of wood flour is 0.249 mm/min.