• Title/Summary/Keyword: Baekdusan

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Growth Characteristics of Microorganism on Lapilli-Cement mixed Bioblocks (화산력-시멘트 혼합 바이오 블록의 미생물 생장 특성)

  • Park, Sung-Yong;Park, Duck-Hwan;Kim, Hyun-Sun;Kim, Jung-Myeon;Lim, Hyun-Taek;Bae, Su-Bin;Kim, Yong-Seong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.57 no.1
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    • pp.111-118
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    • 2015
  • This research aims to utilize lapilli from the Mt. Baekdusan as environmently-friendly construction material. First of all, the neutralizing method for fabricating lapilli-cement-mixed bioblock was examined. And then, by use of the neuralized bioblock with microorganism for water purification, the growth inhibition effect against the pathogenic coliform bacillus was evaluated. The result regarding growth inhibition effect on pathogenic coliform bacillus indicates that the pretreatment condition, which is a concurrent procession with aqueous solution of 10% di-ammonium Phosphate after water curing, led to pH degraded below 10 which was the target value. Therefore it was concluded that the method was effective on bio-block neutralization. The microorganisms purifying water and di-ammonium phosphate were detected through the examination for microorganism existence on the bioblock, therefore it was concluded that the bioblock composed of lapilli and cement is able to be utilized in various structures as an environment friendly construction material.

Selecting Hazardous Volcanoes that May Cause a Widespread Volcanic Ash Disaster to the Korean Peninsula (한반도에 광역화산재 재해를 발생할 수 있는 위험화산의 선정)

  • Yun, Sung-Hyo;Choi, Eun-Kyeong;Chang, Cheolwoo
    • Journal of the Korean earth science society
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    • v.37 no.6
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    • pp.346-358
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    • 2016
  • This study built the volcano Data Base(DB) of 289 active volcanoes around the Korean Peninsula, Japan, China (include Taiwan), and Russia Kamchatka area. Twenty nine more hazardous volcanoes including Baekdusan, Ulleungdo and 27 Japanese volcanoes that can cause a widespread ash-fall on the Korean peninsula by potentially explosive eruption were selected. This selection was based on the presence of volcanic activity, whether or not containing dangerous explosive eruption rock types, distance from Seoul, and volcanoes having Plinian eruption history with volcanic explosivity index (VEI) 4 or more. The results of this study are utilized for screening high-risk volcanoes that may affect the volcanic disaster caused by a widespread fallout ash. By predicting the extent of spread of ash caused by these hazardous volcanic activities and by analyzing the impact on the Korean peninsula, we suggest that it should be used for helping to predict volcanic ash damages and conduct hazards mitigation research as well.

The Study on the Origins of Geography on the Map of Korea in the Kangxi Atlas (『황여전람도』 「조선도」의 모본(母本) 지도 형태 연구 -규장각한국학연구원 소장 『관동·관서지도』를 중심으로-)

  • Kim, Kihyuk
    • Journal of the Korean association of regional geographers
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    • v.21 no.1
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    • pp.153-175
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    • 2015
  • This study is to analyse Korean map inserted in the "Gwandong Gwanseo-jido(關東 關西地圖)" which is reserved in the Gyujanggak Archives as the mother edition of Korean Map("朝鮮圖") in Kangxi Atlas made in Qing dynasty. Map in Gyujanggak is very similar to the Korean map in the Kangxi atlas in terms of shape of southern part of Korean peninsula, boundary of provinces. Especially over 80% of place names on two maps are coincident and over 90% of islands names are identical. It is revealed that map in the Gyujanggak Archive is the most similar map to the Kangxi Atlas in Korea. This map was produced in 1729~1736 which is late compared to the Kangxi Atlas. This difference of production period shows that mother editon of map in Gyujanggak is the base map of Korean Map in Kangxi atlas. The similarity and differences between those maps show the process of edition of geography in the produce the Kangxi atlas. And map in Gyujanggak shows that production of new type of Korean whole map was began in the late $17^{th}$ century.

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Detailed Morphology and Texture of Microlites in Obsidian observed through Electron Microscopy (전자현미경을 이용한 흑요석 내 미세결정의 형태와 조직 관찰)

  • Jwa, Yong-Joo;Hwang, Ga-hyun
    • Journal of the Korean earth science society
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    • v.39 no.6
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    • pp.568-574
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    • 2018
  • Microlite is crystallized under the supercooled condition of volcanic magma. This study reports the morphology and texture of microlites included in the obsidians from the Baekdusan (Mt. Baekdu), Kyushu (Japan), Hokkaido (Japan) and Lipari Island (Italy) by using a scanning electron microscope (SEM). Morphology and texture observed from the back scattered electron (BSE) image could give more detailed information on the microlite crystallization which cannot be acquired from the conventional optical microscope. Ten types of microlites are newly described according to the 14 morphological types of microlites by Clark (1961): Lath, Crenulite, Bacillite, Margarite, Belonites, Trichites, Arculites, Furculite, Scopulites, Scopulitic growth. Detailed description of the ten microlites can be used to interpret the crystallization and paragenetic relations of crystals during the cooling of acidic volcanic magma.

Comparative Analysis of Cataloging Record Related to Korea in the National Libraries of the Main Developing Countries - Focused on 12 Europe and South America Countries - (주요 개발도상국의 국가도서관에 있어 한국관련 목록레코드 비교 분석 - 유럽 및 남미지역 12개국을 중심으로 -)

  • Kim, Jeong-Hyen
    • Journal of Korean Library and Information Science Society
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    • v.47 no.2
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    • pp.1-25
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    • 2016
  • This study was conducted to analyze the characteristics of records related to Korea shown in the cataloging records of national libraries of the main 12 developing countries in Europe and South America. The results are as follows. To begin with, Korea-related records in most national libraries are very poor and under 0.01% of the library. Second, Korean materials usually write Korean in Roman characters except for National Library of Armenia, but there are not marked with the original Korean language and unfeasible Hangeul search. Third, on investigation of the subject distribution in sub criteria of Korea-related records, subject related to history, politics, and economy is largely shown in the highest rate. Fifth, among the Korea-related subject heading, Taekwondo is marked with distinction from Karate in most libraries except for National Library of Argentina. Dokdo is marked with the geographical name of 'Korea' in 8 national libraries and East Sea (Donghae) already is marked with 'Sea of Japan' in 7 national libraries. Amnokgang, Dumangang, and Baekdusan-related records did not search at all in most national libraries.

A Comparative Analysis of Subject Headings Related to Korea in the CCT and NDLSH (『중국분류주제사표(中国分类主题词表)』와 『국립국회도서관건명표목표(国立国会図書館件名標目表)』에 나타난 한국 관련 주제명표목에 대한 비교 분석)

  • Moon, Ji-Hyun
    • Journal of Korean Library and Information Science Society
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    • v.43 no.3
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    • pp.121-141
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    • 2012
  • This study compares and analyzes the numbers and characteristics of Korea-related subjects included in the 2008 Japanese edition of the National Diet Library Subject Headings (NDLSH) and the $2^{nd}$ edition of the Chinese Classified Thesaurus(CCT). The analysis results show that 258 subjects, approximately twice as many as 137 subjects in CCT, were found in NDLSH. There are more pure subjects that exclude the references in CCT than in NDLSH. On the other hand, much more subjects are found in NDLSH in the event that personal names, corporate headings, and subjects combined with detailed headings are included. Meanwhile, more subjects are relatively engaged in the fields of politics, diplomacy, and military in CCT because CCT is characterized by socialism and by being a pro-North Korea. Moreover, the considerable numbers of subjects reflecting North Korea's viewpoint are included in CCT. NDLSH changed only recently the names of both South and North Korea into the "Republic of Korea" and the "Democratic People's Republic of Korea", respectively. On the other hand, CCT more frequently uses "Joseon" than "Korea", and the distinction between the names is unclear. CCT thoroughly supports the stance of the developed country, directly involved in the disputable subjects between two countries such as "Dokdo", "the East Sea", "Dumangang", and "Baekdusan". Both heading lists consider "Balhae" as part of Chinese history in CCT, which has ignored the position of Korea.

Distribution of Pyroclastic Density Currents Determined by Numerical Model at Mt. Baekdu Volcano (백두산 화산에서 수치모형 분석에 의한 화쇄류의 영향 범위)

  • Yun, Sung-Hyo;Chang, Cheolwoo;Kim, Sunkyeong
    • 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.

Geochemical Composition of Volcanic Ash from Historical Eruptions of Mt. Baekdu, Korea (역사시대에 분화한 백두산 화산재의 화학 성분)

  • Yun, Sung-Hyo;Koh, Jeon Seon;Chang, Cheolwoo
    • The Journal of the Petrological Society of Korea
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    • v.27 no.1
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    • pp.37-47
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    • 2018
  • Volcanic ash samples of historical eruptions from Mt. Baekdu were analyzed for major oxides, trace and rare earth elements by a variety of analytical techniques. The results indicate that the ashes consist of approximately 58.8~71.1 wt.% $SiO_2$, 9.6~16.8 wt.% $Al_2O_3$, 4.5~6.9 wt.% $Fe_2O_{3t}$, 0.1~1.7 wt.% MgO, 0.3~1.6 wt.% CaO, 5.2~6.3 wt.% $Na_2O$, 4.3~5.9 wt.% $K_2O$ and less than 1.2 wt.% $TiO_2$. Thirty two trace metals including Ba, Cu, Cr. Co, Ni, Sr, V, Zn, and Zr were analyzed. The ashes can be divided two groups: group A(1 ka Millennium pumice, 1668 and $190{\underline{3}}$ pumice) and group B(1702 pumice) according to the relative enrichment of HREEs. The abundances of heavy metals such as Cu, Co, Mn, and Zn were relatively low. As compared to the Sakurajima volcanic ash, Baekdusan volcanic ash has low concentrations of Y, Nb, Pb, U, Sc, V, Ni and Cu and high concentrations of Zr, Ba, Hf, Cr, Co, Zn and rare-earth (except Eu).

Reflecting on the History and Future of Republic of Korea Navy (대한민국 해군창설 : 회고와 당부)

  • Hahm, Myung-Soo
    • Strategy21
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    • s.37
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    • pp.5-31
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    • 2015
  • The Republic of Korean Navy (ROKN) started from scratch. However, ROKN demonstrated its Blue Navy capabilities successfully to the entire world by conducting "Operation Early Dawn" at the Aden Bay, Yemen in Jan 2011. On the event of the 70th anniversary of the ROKN, I would like to retrospect past gleaning from voyages and challenges we had in the past. At the very inception of the ROKN, Korean government as well as senior military leaders recognized that it had no time to spare to clean up military those were insinuated deeply by communist agents. It was the top priority of the government. The Mongumpo Operation which was not well known, conducted by ROKN was one of the clean-up drive. The Korean War sometimes called as "a fire from land put-off at the sea". The world famous "Incheon Landing" which reversed war situation from the Nakdong Perimeter also done by Sea Power. ROKN conducted various maritime operations including not only Incheon Landing, but amphibious operation at Hungnam, mine sweeping, sea convoy, Wonsan Withdrawal. On the same day of the Korean War started, 25th June 1950, unless the victory of the ROKNS Baekdusan (PC 701) at the Korean Strait, the waning lamp light of Korea could not be rekindled by the participation of the U.N. The ROKN rescued the 17th regiment of Korean Army from the isolation at the Ongjin Peninsular and transported gold and silver bars stored at the Bank of Korea to the Navy supply deposit in Jinhae safely. ROKN special intelligence unit conducted critical HUMINT which led Incheon Landing success. One of important mission ROKN conducted successfully was not only transporting war fighting materials but also U.S. provided grains to starving Koreans. ROKN participated Vietnam campaign from 1960s and conducted numerous maritime transportation operations supplying materials to Vietnam military forces along the long coastal lines. Experienced Naval Officers and enlisted men who discharged and acquired as merchant marine certificate supported most of the U.S. sea lift operations throughout the Vietnam campaign. ROK-US Combined Forces which had been honed and improved its war fighting capabilities through the Korean War and out of Vietnam jungle playing key deterrent against threat from north Korea. However, those threat level will be completely different when north Korea finish its nuclear weapon ambition. In order to stand firm against north Korean nuclear threat, I would like to expect strong political leadership supporting nuclear submarine for ROKN.

A Comparative Analysis of Cataloging Records Related to Korea in the National Libraries of the Major Developing Countries: Focused on 10 Asian and African Countries (주요 개발도상국의 국가도서관에 있어 한국관련 목록레코드 비교 분석 - 아시아 및 아프리카지역 10개국을 중심으로 -)

  • Kim, Jeong-Hyen
    • Journal of the Korean Society for Library and Information Science
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    • v.52 no.1
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    • pp.65-86
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    • 2018
  • This study was conducted to analyze the characteristics of records related to Korea shown in the cataloging records of national libraries of the main 10 developing countries in Asia and Africa. The results are as follows. To begin with, Korea-related records in most national libraries are very poor and under 0.1% of the library. Except for National Library of Viet Nam, the figure is under 3,000 volumes and generally 2 times less than Japan related records. Second, except for National Library of Iran and Viet Nam most national libraries romanize Korean materials, there are not marked with the original Korean language and unfeasible Hangeul search. Third, on investigation of the subject distribution in sub criteria of Korea-related records, subject related to history and economy is largely shown in the highest rate. Fifth, among the Korea-related subject heading, Taekwondo is marked with distinction from Karate in most libraries except for 7 national libraries. Dokdo is marked with the geographical name of 'Korea' in 7 national libraries and East Sea (Donghae) already is marked with 'Japan, Sea of' in 7 national libraries. Amnokgang, Dumangang, and Baekdusan-related records did not search at all in most national libraries.