• The Journal of the Petrological Society of Korea
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• v.23 no.4
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• pp.351-366
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• 2014

We assumed the situation where an eruption column had been formed by the explosive Plinian eruption from Mt. Baekdu and that the collapse of eruption column had caused pyroclastic density currents to occur. Based on this assumption, we simulated by using a Titan2D model. To find out about the range of the impacts of pyroclastic density currents by volcanic eruption scenarios, we studied the distance for the range of the impacts by VEIs. To compare the results by each volcanic eruption scenario, we set the location of the vent on the 8-direction flank of the outer rim and on the center of the caldera, the internal friction angle of the pyroclastic density currents as $35^{\circ}$, the bed friction angle as $16^{\circ}$. We set the pile height of column collapse and the vent diameter with various VEIs. We properly assumed the height of the column collapse, the diameter of the vent, the initial rates of the column collapse and the simulation period, based on the VEIs, gravity and the volume of the collapsed volcanic ash. According to the comparative analysis of the simulation results based on the increase of the eruption, the higher VEI by the increase of eruption products, the farther the pyroclastic density currents disperse. To the northwest from the vent on the northeast slope of the outer rim of the caldera, the impact range was 3.3 km, 4.6 km, 13.2 km, 24.0 km, 50.2 km, 83.4 km or more from VEI=2 to VEI=7, respectively. Once the database has been fully constructed, it can be used as a very important material in terms of disaster prevention and emergency management, which aim to minimize human and material damages in the vicinity of Mt. Baekdu when its eruption causes the pyroclastic density currents to occur.

• The Journal of Engineering Geology
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• v.28 no.4
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• pp.619-630
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• 2018

The purpose of this study is to investigate the existence of faults and intrusive rocks in the volcanic rock mass of Ulleung-do using magnetic anomalies. The magnetic survey data show that basaltic (mafic) rocks have high magnetic anomalies and that trachytic (felsic) rocks have low magnetic anomalies, implying that the anomaly distributions can be used to distinguish between different volcanic rock types that may be covered by regolith (such as alluvial and colluvial deposits) and other sedimentary layers. Our results show that basaltic rocks are not present within the Nari caldera. However, outside the caldera, the occurrence of high magnetic anomaly values of >$1,000{\gamma}$ is presumed to reflect the existence of basaltic craters or volcanic vents that formed prior to the eruption of the trachytic rocks. In particular, the area with anomaly values of >$1,000{\gamma}$ in the vicinity of Namyang-ri, southwest of Ulleung-do, is interpreted as having a high probability of hosting a crater and vent originating from mafic volcanism.

• Industry Promotion Research
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• v.9 no.2
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• pp.37-44
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• 2024

This study selected the worst-case scenario for fireball and vapor cloud explosion (VCE) of a styrene monomer storage tank installed in a petrochemical production plant and performed damage prediction and accident impact analysis. The range of influence of radiant heat and overpressure due to fireball and vapor VCE during the abnormal polymerization reaction of styrene monomer, the main component of the mixed residue oil storage tank, was quantitatively analyzed by applying the e-CA accident damage prediction program. The damage impact areas of radiant heat and explosion overpressure are analyzed to have a maximum radius of 1,150m and 626m, respectively. People within 1,150m of radiant heat of 4kW/m2 may have their skin swell when exposed to it for 20 seconds. In buildings within 626m, where an explosion overpressure of 21kPa is applied, steel structures may be damaged and separated from the foundation, and people may suffer physical injuries. In the event of a fire, explosion or leak, determine the risk standards such as the degree of risk and acceptability to workers in the work place, nearby residents, or surrounding facilities due to radiant heat or overpressure, identify the hazards and risks of the materials handled, and establish an emergency response system. It is expected that it will be helpful in establishing measures to minimize damage to workplaces through improvement and investment activities.

• Proceedings of the KOR-KST Conference
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• 1995.05a
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• pp.77-82
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• 1995

본문수선대장강구적력사변천화지리조건진행료개술,지출료장강구재중국경제발전 화대외무역여교왕중적중요지위.통과대장강구이십일세기개발목표적론술,제출료건설 월강통도,확대장강구월강능력적필요성.위료주호건설장강구월강통도적전기준비공 작,대월강통도진행료규화구상,대건설월강통도수요인기관주적약간문제작료굉관론 술: 1. 규화월강통도적기본원칙; 2. 선택월강방식적주요의거, 3. 수건월강통도적 건설방침

• Journal of the Speleological Society of Korea
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• v.34 no.35
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• pp.67-77
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• 1993

제주도는 한반도의 남서 해안에 따로 떨어겨 있는 화산섬으로 동경 126$^{\circ}$09'44"~120$^{\circ}$57'00", 북위 33$^{\circ}$11'28"~33$^{\circ}$33'45"에 위치하며 N70E 장축을 가지는 동서 약 73km, 남북 약 32km의 타원형을 이루며 중앙에 한라산 1,950m를 중심으로 단추형의 화산섬을 이룬다. 장축인 동서방향은 매우 완만한 사면 3~5$^{\circ}$를 이루고 단축인 남북방향은 약간 급한 경사 5~7$^{\circ}$를 갖는 Aspite형 화산이다. 이것은 화산 분출이 전반기에는 강력한 분출이었으나 추기에 백록담을 화구로 한 중심 분출에 기인된 것이다.(중략)

• Spatial Information Research
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• v.17 no.1
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• pp.103-115
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• 2009

Recently, the seabed facility is gradually being increased based on the development of harbor and the coastal area. However, the comparison between the survey data with the chart still shows the significant differences leading to various disasters over sea accident. Therefore, in this study, the investigation on the seabed facility were performed in 5 areas through an accuracy analysis using an up-to-date surveying equipment(MBES, SSS and SBP). Based on the study more systematic management on the seabed facility, more accurate method on the surveying, and some considerations on the related policies are suggested. Through the study, we obtained more accurate measurement on depth and seabed piping forms in Jakdo and Pyong-tack, on sunken ship in a Mok-po, on seabed crater in Je-ju. In addition, it was possible to present the method for the construction of information infra and a connection with the seabed facility. The criteria on the equipment's specification, surveying method and procedures are set by the experiments and the investigation and surveying accuracy on the seabed facilities are also suggested.

• KOMUNHWA
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• no.57
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• pp.157-194
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• 2001

Taeshil means the facility where tae is buried through appropriate rituals and procedures when a descendant of royal family is born. Tae has been taken care of very carefully from old times being considered as lifeline and origin of the owner. Especially,

• Journal of Wetlands Research
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• v.4 no.1
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• pp.1-19
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• 2002

This study was carried out to provide basic data for biodiversity about phytoplankton at crater of Cheju parasite volcano from March to November 2000. In the study area, we identified 6 class 12 order 23 family 44 genus 87 species 13 variety 2 forma, Which were totally 102 taxa. Those were composed of 40 taxa(39.2%) of Chlorophyceae, 34 taxa(33.3%) of Bacillariophyceae, 14 taxa(l3.7%) of Canophyceae, 9 taxa(8.8%) of Euglenophyceae, 3 taxa(3.0%) of Dinophyceae, 2 taxa(2.0%) of Chrysophyceae, respectably. Monthly appearance of phytoplankton were 74 taxa on March, 46 taxa on May, 21 taxa on August, 22 taxa on November. Biodiversity of phytoplankton by station was 54 taxa in Moolchat, 22 taxa in Moolyoungari, 26 taxa in Mooljangauri, 12 taxa in Dongsuack, 6 taxa in Asungseang, 27 taxa in Samiaorum, respectably.

• Journal of the Korean Institute of Gas
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• v.15 no.2
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• pp.57-62
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• 2011

DME(Dimethyl Ehther) is considered as an attractive fuel in terms of clean, environmentally friendly form of energy, multi-source and multi-purpose. As the physical properties of DME are almost similar to LPG, DME can be mixed with LPG and DME-LPG mixture fuels seem to be employed without major remodeling of the existing LPG supply infrastructure. However, little attention has been given to the effect of different DME-LPG mixture fuels on consequence analysis to adjacent facilities, buildings and etc. In this work, the consequence analysis by different DME-LPG mixture fuels has been done. The results were discussed in terms of release rate, jet fire, vapor cloud explosions, BLEVEs and etc. It was found that the consequences estimated from fire and explosion scenarios assumed were almost similar for both LPG and DME 20 %.

• Journal of The Geomorphological Association of Korea
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• v.18 no.4
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• pp.79-96
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• 2011

Volcanic landforms are classified into the volcanic edifice produced through constructive processes of eruption and the crater generated by destructive processes of eruption. Both landforms are distributed around Korean Peninsula including attaching islands. However, only a few regions such as Mt. Baekdu, Jeju Island, Ulleung Island, and Chugaryeong, which are closely related with the volcanic eruption occurred during the Quaternary, could be considered as a volcanic landform. It results in categorizing the volcanic landform as an unusual topography in Korea. The study of Korean researchers on the volcanic landform were regularized in 1970s on Jeju Island, in 1980s on Ulleung Island, and in 1990s on Mt. Baekdu, respectively. Oreums and lava tubes in Jeju Island have been also examined since 1980s. Compared with other fields of geomorphology, researches as well as researchers on the volcanic landform are very few in Korea. Geomorphologists are expected to perform an active research in that the volcanic landform of Korea have diverse values.