• Journal of Environmental Science International
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• v.19 no.9
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• pp.1153-1159
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• 2010

Identification of probability distribution for water quality constituents from specific land use is important to achieve successful implementation of TMDL program. In this 3-year study, distribution of discharge and BOD(Biological Oxygen Demand) concentration from paddy rice fields were monitored. Four probability distributions, normal, log-normal, Gamma and Weibull were fitted and the goodness-of-fit was assessed using probability plots and Kolmogorov-Smirnov test. $EMC_s$ of BOD in runoff from paddy field ranged 0.37 to $7.99\;mgL^{-1}$, and all four probability distributions were acceptable. But the normal distribution would be preferred for BOD from paddy fields considering nature of straight forward application.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.435-439
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• 2011

최근 홍수로 제체누수 및 지반누수에 의해 제방이 피해를 입는 사례가 증가하였다. 특히 2000년대부터 Piping 현상으로 제방이 붕괴되는 일들이 다수 발생하고 있어 기존 제방의 안정성 검토와 신설 제방 설계의 필요성이 제기되고 있다. 우리나라의 제방 침투해석은 2차원 비정상 침투해석을 하고 있으나 이 경우 외력 조건으로 외수위에 대한 하천의 홍수파형이 필요하다. 본 연구에서는 설계 홍수파형 유도를 위하여 금호강 상류지점인 금호 수위관측소에서 설계 홍수위 및 시간별 홍수위 등을 조사하여 과거 홍수사상의 시간별 수위곡선을 분석하였다. 수위곡선은 Huff의 4분위법에 따라 무차원화 시키기 위하여 각 홍수위의 누가지속시간과 누가 홍수위를 구하고 Weibull분포의 도시위치 공식을 적용하여 10~90％ 무차원 누가곡선을 도시하였다. 일반적으로 통계 해석상 중앙값을 나타내는 50％ 무차원 누가곡선을 사용하기 때문에 본 연구에서도 50％ 무차원 누가곡선을 사용하여 무차원 설계 홍수파형을 유도하였다. 새로이 유도한 무차원 설계 홍수파형을 외력 조건으로 하고, 금호강 유역의 인근 제방을 모형으로 하여 SEEP/W 프로그램으로 2차원 침투해석을 실시함으로써 그동안 외수위를 계획 제방고까지 인위적으로 연장시켜 사용하는 문제점을 해결하고 우리나라의 실정에 맞는 설계 홍수파형을 유도하여 하천제방 설계 및 기존 제방의 안정성 검토에 활용될 수 있는 연구를 수행하고자 한다.

• Water for future
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• v.25 no.4
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• pp.51-59
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• 1992

Recently the pysically based precipitation model was developed by Geogakakos and Bras(1984) for the storm event. This is a modified version of the model. In a different way from the model, in this paper, it is emphasized that the hyderometeor size distribution(HSD)is subject to rainfall intensity and effects on the productivity of precipitation. The to HSD functions are applied to the equation of the outflow after mass through the cloud top and base, products of rainfall rate at the ground level, storage of cloud layer. As an input we put the meterological data observed at Chonju in Korea in our models and adjust the parameters included in it. The result show that in the model there is significant deviation between the hourly calculated rainfall rate and the observed data, while it is very small in the our model based on the two HSD.

• Journal of Chest Surgery
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• v.36 no.11
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• pp.834-838
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• 2003

Background: Deairing from the heart after open heart surgery(cardiopulmonary bypass) is a very important procedure. Artificial arteriovenous fistula was used to remove air, and the efficiency was evaluated by transesophageal echocardiography. Material and Method: Just before termination of cardiopulmonary bypass, a standard pressure transducer line is connected between the stopcocks of the connections in the arterial and venous circuits, creating a small controlled arteriovenous fistula between the arterial and venous cannulas. The degree of intracardiac air and air removal time were evaluated either by transesophageal echocardiography or direct vision of pressure transducer line. Result: By simple procedure, cardiopulmonary time was shortened and air clearing can be confirmed using echocardiography in a few minutes. Conclusion: Creation of arteriovenous fistula using small connecting line between aortic and venous cannula is a very simple and effective method of deairing and preventing of air embolism after open heart surgery.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.5
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• pp.15-41
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• 2017

The purpose of this study is to present the basic data for conservation of forest ecosystem by surveying and analysing the flora distributed in Nakdong-Jeongmaek Mountains, Korea. The numbers of flora were 901 taxa including 116 families, 433 genera, 790 species, 4 subspecies, 90 varieties, 15 forms and 2 hybrids. The threatened species was Pedicularis ishidoyana. The rare plants were 33 taxa including Pseudostellaria sylvatica, Cimicifuga heracleifolia var. bifida, Isopyrum mandshuricum, Paeonia japonica, Syringa patula var. kamibayshii, Lilium distichum, Iris odaesanensis and so forth. The Korean endemic plants were 35 taxa including Salix koriyanagi, Thalictrum actaefolium var. brevistylum, Corydalis maculata, Lespedeza maritima, Cirsium setidens, Carex okamotoi and so forth. The specific plants by floristic region were 155 taxa including 55 taxa of grade I, 41 taxa of grade II, 36 taxa of grade III, 18 taxa of grade IV and 5 taxa of grade V. The naturalized plants were 62 taxa including Rumex obtusifolius, Amaranthus lividus, Medicago sativa, Geranium carolinianum, Malva sylvestris var. mauritiana, Foeniculum vulgare, Sonchus oleraceus, Tradescantia reflexa and so forth. The invasive alien plants were 5 taxa including Rumex acetocella, Solanum carolinense, Ambrosia artemisiifolia, Aster pilosus and Lactuca scariola.

• Advances in pediatric surgery
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• v.8 no.1
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• pp.23-27
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• 2002

Infantile hypertrophic pyloric stenosis (IHPS) a common childhood disorders characterized by nonbilious projectile vomiting, an olive shaped mass in the right upper quadrant of the abdomen and visible gastric peristaltic wave in the upper abdomen. Its etiology and pathogenesis are not clear but abnormal nerve distribution of the pylorus has been $postulated^{2-6}$. We performed immunocytochemical staning to the pyloric muscle from 10 IHPS and 3 controls patients, utilizing specific monoclonal antibody to NCAM(neural cell adhesion molecule). In IHPS patients, the number of NCAM protein immunoreactive nerve fibers were less than that in normal subjects. Auerbach myenteric plexuse was well developed and interbundle nerve plexuse was present but nerve fibers supplying individual muscle cells in smooth muscle bundles were poorly developed. These results indicate reduction of innervation in smooth muscles in IHPS patients that possibly contributes to the pathogenesis of IHPS.

• Korean Journal of Optics and Photonics
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• v.20 no.4
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• pp.236-240
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• 2009

LED modules, based on MCPCB with a hard barrier oxide layer and an improved thermal dissipation property, are presented. Reflecting cups were also formed on the surface of the MCPCB such that optical coupling between neighboring chips was minimized for improving the photon absorption loss. LED chips were directly attached on the MCPCB by using the COB (Chip On Board) scheme. The LED modules showed significantly enhanced light outputs, compared to the LED modules based on conventional MCPCBs.

• Journal of the Mineralogical Society of Korea
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• v.7 no.2
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• pp.97-110
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• 1994

고사리광산의 도석에는 다량의 석영과 함께 녹니석/스멕타이트 혼합층광물, 운도/스멕타이트 혼합층광물, 카오리나이트와 같은 점토광물이 산출한다. 이들 점토광물에 대해 주로 X-선회전분석과 화학분석 등을 이용하여 광물학적 특성을 검토하였다. 이 광산의 도석은 녹니석/스멕타이트 혼합층광물을 다량 함유하는 것이 특징으로 나타났다. 이 녹니석/스멕타이트 혼합층광물은 Li을 함유하는 돈바싸이트로 된 녹니석층과 바이델라이트에 가까운 스apr타이트층으로 구성된 혼합층구조를 이룬다. 이 곳에 산출하는 운모/스멕타이트 혼합층광물은 모두 약 15% 이하의 팽윤층을 포함하는 것으로 되어 있다.이 광산의 도석은 백악기의 유문암 및 유문암질 응회암이 열수변질작용을 받아 형성된 것으로 나타났다. 점토광물조합의 분포상태에 의해 대략적인 변질분대가 나누어진다. 중심부인 강변질대에서는 다량의 녹니석/스텍타이트 혼합층광물이 나타나며 카오리나이트가 수받되기도 한다. 그 외곽지역의 약변질대에서는 점토광물로서 운모/스멕타이트 혼합층광물이 주로 나타난다. 카오리나이트는 주로 열극이나 그 주위에 국부적으로 산출되는 경향이 있다. 이와 같은 변질광물의 산출상태로 볼 때 변질작용의 진행에 따라 운모/스멕타이트 혼합층광물이 먼저 형성된 후 이것의 일부가 녹니석/스맥타이트 혼합층광물 및 카오리나이트로 변화된 것으로 생각된다. 도 카오리나이트는 열수의 공급이 많은 열극부에서 녹니석/스멕타이트 혼합층 광물과 거의 동시기에 침전된 것으로 생각된다. 이 광산에서 산출하는 일부 운모/스멕타이트 혼합층광물은 후기의 변질작용에 의해 형성된 것도 포함된다.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.05
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• pp.113-116
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• 1995

Steady and physiological flows of a Newtonian fluid and blood in the bifurcated arterial vessel are numerically simulated. Distributions of velocity, pressure and wall shear stress in the bifurcated arterial vessel are calculated to investigate the differences between steady and physiological flows. For the given Reynolds number physiological flow characteristics of a Newtonian fluid and blood in the bifurcated arterial vessel are quite different from those of steady flows. No flow separation or flow reversal in the bifurcated region in the downstream after stenosis appears during the acceleration phase. Also, no recirculation region is seen for steady flows. However, during the deceleration phase the flow began to exhibit flow reversal, which is eventually extended to the entire wall region.

• Journal of Environmental Science International
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• v.12 no.10
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• pp.1121-1129
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• 2003

We report the distributions of Sb and As in the surface sediment of the Yellow Sea and the coastal areas of Korea. The mean concentrations of Sb and As range from 0.68 ppm to 1.01 ppm and from 7.4 ppm to 15.8 ppm, respectively, and show relatively the high concentrations at the coast of Weolseong in the East Sea for Sb and at the coast of Gadeok Island in the South Sea far As. This may be due to the anthropogenic input of these elements via river and atmosphere from industry complex and agriculture regions around the study areas. Because of the difference of clay to silt proportion, the correlation between silt plus clay contents and Sb, As in the coastal surface sediment of Korea is not shown, the concentrations of Sb and As vary widely for the sample in which the silt plus clay contents are the same. Therefore, we suggest that the distribution patterns of Sb and As in surface sediment of the Yellow Sea and the coastal areas of Korea are mainly controlled by the anthropogenic inputs and the sediment characteristics. On the other hand, the Sb concentrations are lower than those of the lowest effect level which is the standard of judgment for contamination, while the As concentrations are higher than those of the lowest effect level. This implies that the surface sediments of the Yellow Sea and the coastal areas of Korea are considerably contaminated for As.