• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.2
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• pp.69-79
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• 2009

Major and trace elements were analyzed in three core sediments to investigate geochemical characteristics of East Sea sediments and provenance changes during late Quaternary in Ulleung Basin. Comparing with Yellow and South Sea sediments, contents of major elements were generally similar while contents of trace elements were significantly different. Furthermore, within this basin, there were some variabilities in trace element compositions. In the western slope sediments (WS), Mo was enriched over 6 times as much as other sites. On the other hand, Zr, Nb, Hf and Ta were enriched in basin sediments (Basin), and Ca and Cs were enriched in southern slope sediments (SS). After excluding elements derived from biogenic, authigenic and diagenetic origins, the lithogenic elements (K, Ti, Cs, Zr, Nb, Hf and Ta) could be classified into three groups from the comparison of element/Al ratios among cores. The first group consisted of elements (K and Ti) that showed the nearly similar element/Al ratios among three cores. The second group contained Cs which showed significant difference between two slope sediments. The third group elements (Zr, Nb, Hf and Ta) showed highly enriched in basin relative to both slope areas. The depth profiles of metal/Al ratios in basin sediments provided the following interpretation for the compositions of sediment and their variation. From 10,000 yr B.P. to 7,000 yr B.P. two lithogenic components (volcanic ashes and western slope sediments) were mixed and deposited in the basin. After 7,000 yr B.P., however, southern slope sediments were mixed with volcanic ashes and deposited in basin area. This event of source change is nearly close to inflow period of the Tsushima Warm Current to Ulleung Basin. Thus, it might be suggested that element geochemistry in Ulleung basin sediment indicate the change of current system in the study area.

• Economic and Environmental Geology
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• v.46 no.3
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• pp.267-278
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• 2013

The East African Rift System(EARS) is known to be hosted epithermal Au-Ag deposits, and the best-known example is Main Ethiopian Rift Valley(MER) related to Quaternary bimodal volcanism. Large horst-graben system during rifting provides open space for emplacement of bimodal magmas and flow channel of geothermal fluids. In recent, large hydrothermally altered zones(Shala, Langano, and Allalobeda) and hot spring related to deeply circulating geothermal water have been increasing their importance due to new discoveries in MER and Danakil depression. The hot springs in Shala and Allalobeda occur as boiling pool and geyser on the surface, whereas some areas didn't observe them due to decreasing ground water table. The host rocks are altered to quartz, kaolinite, illite, smectite, and chlorite due to interaction with rising geothermal water. The hot springs in MER are neutral to slightly alkaline pH(7.88~8.83) and mostly classified into $HCO_3{^-}$ type geothermal water. They are strongly depleted in Au, and Ag, but show a higher Se concentration of up to 26.7 ppm. In contrast, siliceous altered rocks around hot springs are strongly enriched in Pb(up to 33 ppm, Shala), Zn(up to 313 ppm, Shala), Cu(up to 53.1 ppm, Demaegona), and Mn(up to 0.18 wt%t, Shala). In conclusion, anomalous Se in hot spring water, Pb, Zn, Cu, and Mn in siliceous altered rocks, and new discoveries in MER have been increasing potential for epithermal gold mineralization.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.923-927
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• 2006

국내의 수자원장기종합계획(건교부, 2001년)에 의하면 농업용수는 우리나라 수자원의 48%를 차지하고 있으며 하천유지용수를 제외한 이용량으로 보면 62%에 해당하는 최대 용수이용 부문이다. 그러므로, 농업용수의 효율적인 계획과 관리는 우리나라 수자원의 효율적인 이용에 있어서 매우 중요하다. 우리나라의 농촌은 1970년 이후 급격한 도시화, 산업화로 농업인구의 격감과 노동력의 부족에 따른 농업용 기계가 보급되게 됨에 따라, 과거의 주로 인력에 의한 벼농사의 영농방식에 변화가 생기게 되었다. 그러한 영농전반의 변화들은 직파재배, 집단육묘, 비닐하우스를 이용한 못자리, 어린모 이앙법 등 다양한 방식으로 벼재배 방식에서도 나타나고 있다. 이러한 영농상황의 변화는 농업용수공급 현황에도 영향을 미쳐 물이용 형태가 과거와 많은 차이를 보임을 알 수 있다. 이러한 차이는 최근의 연구결과에서도 나타나고 있는데 2002년 농어촌연구원 '용수수급의 안정성 제고 연구 및 종합시험지구 운영'에 의하면 3개 저수지지구의 계획공급량과 용수공급량 비율이 $0.7{\sim}1.3$이며, 영농초기 $4{\sim}5$월에 특히 차이가 큼을 알 수 있었다. 2001년 한국건설 기술연구원의 '물관리 효율성 제고기술 연구보고서'에 의하면 $4{\sim}5$월에 큰 차이를 보이는 등 농어촌연구원과 비슷한 결과를 나타내었다. 본 연구는 중부지방인 경기 남부지역을 대상으로 영농방식에 대한 조사를 하고 농업용수 공급량을 측정하여 현행 농업용수량 산정기준에 의한 농업용수량과 비교함으로써 변화된 영농환경을 고려한 적정한 관개 용수량 산정방법을 제시하는 것을 목적으로 하고 있다.악할 수 없었던 수체내의 많은 특징을 파악 할 수 있었다.. 중랑천 유역의 소배수구역을 대상으로 연중 발생하는 큰 호우사상에 대해 임의의 강우관측소를 결측지점으로 가정하고 주변의 강우관측소로부터 각각의 방법을 이용해 가중치들을 산정하여 결측지점의 강우량 값을 보정하고자 하였다. 또한 각각의 방법을 이용하여 얻어진 결과에 대해 실측값과 보정값의 오차정도를 평균절대오차법(Mean Absolute Error)과 제곱평균제곱근오차법(Root Mean Squared Error)에 의해 산정하여 보정 방법간의 효율성을 검토하고자 하였다.9년, 그리고 2010년${\sim}$2019년까지 총 4구간으로 나누어 결과를 도출하였으며 예상한 바와 같이 후반기 20년 동안에 세 가지 지표가 취약해 지는 것을 확인할 수 있었고, 특히 2000년부터 2009년까지 10년 동안에는 더욱 취약해짐을 확인할 수 있었다.를 보임에 따라 그 정책적 효과는 때로 역기능적인 결과로 초래하였다. 그럼에도 불구하고 이 연구결과를 통하여 최소한 주식시장(株式市場)에서 위탁증거금제도는 그 제도적 의의가 여전히 있다는 사실이 확인되었다. 또한 우리나라 주식시장에서 통상 과열투기 행위가 빈번히 일어나 주식시장을 교란시킴으로써 건전한 투자풍토조성에 저해된다는 저간의 우려가 매우 커왔으나 표본 기간동안에 대하여 실증분석을 한 결과 주식시장 전체적으로 볼 때 주가변동율(株價變動率), 특히 초과주가변동율(超過株價變動率)에 미치는 영향이 그다지 심각한 정도는 아니었으며 오히려 우리나라의 주식시장은 미국시장에 비해 주가가 비교적 안정적인 수준을 유지해 왔다고 볼 수 있다.36.4%)와 외식을 선호(29.1%)${\lrcorner

• Journal of Plant Biotechnology
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• v.44 no.3
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• pp.296-302
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• 2017

Rice (Oryza sativa) cultivars show an impairment of growth and development in response to abiotic stresses such as drought, salinity, heat and cold at the early seedling stage. The tolerance to heat stress in plants has been genetically modulated by the overexpression of heat shock transcription factor genes or proteins. In addition to a high temperature-tolerance that has also been altered by elevating levels of osmolytes, increasing levels of cell detoxification enzymes and through altering membrane fluidity. To examine the heat tolerance in transgenic rice plants, three OsOPT10 overexpressing lines were characterized through a physiological analysis, which examined factors such as the electrolyte leakage (EL), soluble sugar and proline contents. We further functionally characterized the OsOPT10 gene and found that heat induced the expression of OsOPT10 and P5CS gene related proline biosynthesis. It has been suggested that the expression of OsOPT10 led to elevated heat tolerance in transgenic lines.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.532-536
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• 2007

급속한 도시화 및 지구온난화로 인한 집중호우로 홍수피해가 해마다 증가하고 있다. 홍수피해를 최소화하기 위하여 4대강 중심의 홍수예경보시스템이 구축되는 등 다양한 제도적 장치가 마련되고 있으나 중소하천이 분포되어 있는 도시유역에서의 홍수예측기능은 부족한 실정이다. 본 연구에서는 중소 도시하천에 적용 가능한 실시간 도시홍수예측서비스 시스템(Realtime Urban Flood Forecasting Service, U-FFS)을 개발하였다. 경기도 성남에 위치한 탄천을 대상유역으로 선정하고 실시간 강우 및 수위관측소를 설치하여 수문데이타를 수집하였으며 이를 바탕으로 수위예측모형을 구축하였다. 모형구축에는 이미 국내외 학계에서 그 정확도가 입증된 바 있는 Data-driven 모델의 일종인 ANFIS(Adaptive Neuro-Fuzzy Inference System)를 이용하였다. 개발된 수위예측모형은 지정된 시간에 자동으로 작동 가능한 실행파일로 프로그래밍되어 최종적으로 홍수예측 웹서비스와 연동된다. U-FFS는 집중호우 발생 시 최종 유출구의 30분, 1시간, 2시간 후의 수위 예측값을 웹 상을 통해 제공함으로써 언제 어디서나 홍수예측 정보를 누구나 손쉽게 획득할 수 있는 장점이 있다. 시범운영 결과, 30분 및 1시간 후의 수위 예측은 정확도가 매우 뛰어났으며 2시간 후의 수위 예측의 정확성은 다소 떨어지는 것으로 확인되었으나 전반적인 홍수예측 판단에는 무리가 없을 것으로 예상된다. 본 시스템의 홍수예측모형은 생성 및 수정이 간편하여 그 활용성이 매우 높을 것으로 기대된다. 특히 안전함을 지향하는 각종 U-City나 홍수피해가 빈번한 도시유역에 적용하면 기존 시스템과 차별화된 실시간 홍수예측 서비스가 가능해져 홍수피해를 최소화할 수 있을 것이다. 취수구 직경 D의 3.3배를 벗어나지 않는다는 결과를 도출할 수 있었다.링 목적으로 사용될 수 있다. 본 연구에서 개발한 영상수위계는 한강홍수통제소 관할의 전류, 청담대교 등 4개소 낙동강 홍수통제소 2개소, 지자체 등에 적용되었으며, 적용 결과 비교적 안정적이면서 정확하게 수위를 측정하는 것으로 나타났다. 한편 기존 CCD 카메라 이외에 CCTV를 이용한 영상수위계를 개발하여 영상의 화질 개선뿐 아니라 하천화상 감시 기능을 강화하였다.소류의 섭취율은 높았다. 집단간의 상관도를 보면 교육별로 김치, 장아찌, 콩이 각각 p>0.5 수준에서 유의한 차가 없었고, 나머지는 유의한 차가 있었다. 연령별로는 멸치가 유의한 차가 없었고(p>0.5), 수입별로는 콩이 유의한 차가 없었다(p>0.5). 4. 영양지식(營養知識) 검토 가정생활(家庭生活)에 필요(必要)한 일반적(一般的)인 영양지식(營養知識)은 대체적으로 낮은 편이었다. 어린이 영양, 편식의 해로움, 비만증의 해로움, 임신부 그리고 수유부 영양에 대하여는 일반적으로 알고 있다고 하였으며, 그다음으로 이유기 영양, 어린이 발육에 필요한 식품, 식품과 영양소와의 관계, 우유의 성분, 노인영양에 대하여 잘 알고 있는 비율이 낮았으며, 인체의 영양소, 식단작성여부, 간식의 이론, 식품감별법에 대하여는 가장 낮은 비율을 나타냈다. 각 영양지식은 교육정도가 높을수록 영양지식이 높았고, 교육별 집단간의 유의한 차가 나타났다. (0.001

• The Journal of the Petrological Society of Korea
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• v.16 no.2 s.48
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• pp.59-72
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• 2007

Kilauea volcano located in the southern part of Hawaii island chains has been formed by continuous and sporadic eruption activities from 16 century to September of 1982. Kilauea volcano was investigated from collecting the samples of basalt to identify the geochemical characteristics of the lavas. Olivine, clinopyroxene, plagioclase, and opaque minerals with glass groundmass are observed. Clinopyroxene formed glomerophopyritic texture with plagioclase and zoning texture was observed in some of plagioclase phenocrysts. Major elements such as $K_2O$, $P_2O_5$, $TiO_2$ increased with respect to MgO. $Al_2O_3$ and CaO show the kink on Marker diagram due to the crystal fractionation of plagioclase and clinopyroxene with plagioclase respectively. Olivine has a wide range of Fo% ranging from 60 to 90, and MnO and FeO in the olivine are decreased with increasing Fo% oppositely increased $SiO_2$, MgO, and NiO. Ni in the whole rock is controlled not only by the mode of olivine but also by the Ni abondance in the olivine.

• Journal of Korean Elementary Science Education
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• v.24 no.4
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• pp.337-344
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• 2005

The purpose of this study is to analyze field trip activities in the elementary school science textbook developed under the 7th national curriculum. The results indicated there was an average of 4.25 field trip activities each semester presented in the textbook from the 3rd to 6th grade, mostly related to earth science and biology. The places for field trips were limited to in-school environment and natural sites in communities, and mostly purported to gain understanding of rudimentary concepts. Field trip activities were intended to facilitate science knowledge and understanding in order to integrate with the textbook content rather than offering students simple one-time activities. Most activities in the textbook guided students step by step. The starting or follow-up activities in the fields trips and reminder for cautions were not clearly presented. In order for the field trips to integrate with the content of the curriculum in the text book, they have to be presented in the textbook systematically. It is also imperative to find out various fold trip places related to the content in the curriculum, develop efficient activities dealing with science at the appropriate level for students and increasing interests in science and its teaming.

• Journal of Conservation Science
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• v.36 no.6
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• pp.494-504
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• 2020

Ten historic sites (denoted as A- J in this study) of a tomb were found during the construction of the east-west expressway in District 2 of Hyangnam, Hwaseong, which is implemented by the Gyeonggi-do headquarters of the Korea Land & Housing Corporation. Thetombswere first detected at siteH, and further investigations revealed various tombs from the Three Kingdoms period; artifacts such as gilt-bronze shoes and caps were excavated from wooden coffins in the tombs. The pottery examined in this study was the only pottery artifact excavated from the site. Its raw clay was soft and loose, reddish brown, and had quartz and feldspar particles of < 1 mm, which appeared to have been added as reinforcing agents. The firing temperature of the pottery was estimated to be under 800-870 ℃ as the mica remains and tridimite, which is the phase transition mineral of quartz, was not produced; a slight endothermic peak was also detected because of the hydration of sericite at 800 ℃. The condition of the artifact was severely weakened because of various factors, such as soil pressure from the stratum formed over the site and repeated freezing and thawing. The artifact could not be collected alone, and thus, surrounding soil that had attached to the artifact was also collected; the artifact was transported to the laboratory and conservation treatment was conducted in a safe and systematic manner.

• Korean Journal of Environment and Ecology
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• v.37 no.6
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• pp.499-507
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• 2023

This study conducted an empirical analysis on a land purchase requisition policy in Bukhansan National Park to draw the efficacy, limitations and implications of this policy. A logistic regression analysis was conducted to identify factors that affected the landowners' decision on applying for land purchase requisition using the government's records on acquisition of private lands in the park since 2006 when this policy began to be implemented. Results illustrate that the probability that a landowner applied for purchase requisition increased if the land was classified as forest, if a large proportion of the land was designated as the nature conservation district, if it was located farther from park boundary, and if it had higher appraised value per square meter. These results indicate that as the landowners had less chance to utilize their lands, they more likely apply for purchase requisition. These results also imply that the government can achieve a high conservation performance level if private lands are acquire by the land acquisition requisition policy. The logistic regression model also predict that 401m² of the private lands in Bukhansan National Park will likely be purchase-requested in future. Despites its usefulness in mitigating landowners' complaints in national parks, the land purchase requisition policy has not been widely utilized. Based on these empirical results, this study provides policy implications to facilitate the ulitization of this policy.

• The Korean Journal of Air & Space Law and Policy
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• v.35 no.3
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• pp.127-150
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• 2020

A Basic Plan for the Promotion of Space Development (hereinafter referred to as "basic plan"), which prescribes mid- and long-term policy objectives and basic direction-setting on space development every five years, is one of the matters to be deliberated by the National Space Committee. Confirmed February 2018 by the Committee, the 3rd Basic Plan has a unique matter, compared to the 2nd Basic Plan. It is to construct "Korean Positioning System(KPS)". Almost every country in the world including Korea has been relying on GPS. On the occasion of the shooting down of a Korean Air flight 007 by Soviet Russia, GPS Standard Positioning Service has been open to the world. Due to technical errors of GPS or conflict of interests between countries in international relations, however, the above Service can be interrupted at any time. Such cessation might bring extensive damage to the social, economic and security domains of every country. This is why some countries has been constructing an independent global or regional satellite navigation system: EU(Galileo), Russia(Glonass), India(NaVic), Japan(QZSS), and China(Beidou). So does South Korea. Once KPS is built, it is expected to make use of the system in various areas such as transportation, aviation, disaster, construction, defense, ocean, distribution, telecommunication, etc. For this, a pan-governmental governance is needed to be established. And this governance must be based on the law. Korea is richly experienced in developing and operating individually satellite itself, but it has little experience in the simultaneous development and operation of the satellites, ground, and users systems, such as KPS. Therefore we need to review overseas cases, in order to minimize trial and error. U.S. GPS is a classic example.