• Journal of Korea Water Resources Association
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• v.40 no.9
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• pp.709-722
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• 2007

The floods of Korea happens periodically during summer. The cause of heavy rain that provokes floods can be classified into typhoon and localized downpour. The typhoon happens in the tropical region. It causes one of the worst damage to Korea by extreme rainfall and strong wind. Usually, it is known that the flood damage by the typhoon is larger than that by the localized downpour. Therefore, this study classified rainfall events into typhoon events and localized downpour events based on the cause. Through statistical analyses of the rainfall data, this study investigated special quality of the rainfall during the time of typhoon. In analysis results, probability Precipitation calculated by the typhoon events were exposed bigger than that calculated by all rainfall events.

• Journal of Mushroom
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• v.13 no.2
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• pp.125-128
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• 2015

We found about cultivation light environment conditions of Neolentinus lepideus. For the high quality of N. lepideus, lights-out was useful. In the lights-out, the diameter of pileus of N. lepideus was smaller, and the length and the thickness of stipes were longer and larger than in that of lighting. At the LED effect, the orange and red LEDs prolonged the cultivation period in N. lepideus. The yields of N. lepideus under the white, blue and green LEDs were higher, and the number of available stipes of N. lepideus under the white and blue LEDs was higher than that of other LEDs. The diameter of pileus of N. lepideus under the white, blue and green LEDs was higher, and the length and the thickness of stipes under the orange and red LEDs was higher than those of other LEDs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.4
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• pp.1460-1465
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• 2012

The semi-automatic gas metal arc welding equipment was developed and the weldability of zinc coated steel pipes was evaluated in terms of strength, porosity and welding parameters including shielding gas composition. The good bead appearance and the reduction of porosity in the welds could be possibly obtained by adding $O_2$ to Ar. The strength and joint efficiency of welds made by the semi-automatic welding equipment was about 1.8 times higher compared with welds manually made. The integrity of welds was confirmed by the water pressure test as well, Finally, it is expected that the weld productivity will be enhanced even unskilled welders can produce quality welds by operating the semi-automatic welding equipment.

• Journal of Korea Water Resources Association
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• v.43 no.5
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• pp.471-482
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• 2010

Rainfall events in the hydrologic circulation are closely related with various meteorological factors. Therefore, in this research, correlation relationship was analyzed between sea surface temperature of typical meteorological factor and monthly rainfall on Korean peninsula. The cluster analysis was performed monthly average rainfall data, longitude and latitude observed by rainfall observatory in Korea. Results from cluster analysis using monthly rainfall data in South Korea were divided into 4 regions. The principal components of monthly rainfall data were extracted from rainfall stations separated cluster regions. A correlation analysis was performed with extracted principal components and sea surface temperatures. At the results of correlation analysis, positive correlation coefficients were larger than negative correlation coefficients. In addition, The 3 month of principal components on monthly rainfall predicted by locally weighted polynomial regression using observed data of sea surface temperature where biggest correlation coefficients have. The result of forecasting through the locally weighted polynomial regression was revealed differences in accuracy. But, this methods in the research can be analyzed for forecasting about monthly rainfall data. Therefore, continuous research need through hydrological meteorological factors like a sea surface temperature about forecasting of the rainfall events.

• 한국지구물리탐사학회:학술대회논문집
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• 2006.06a
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• pp.187-192
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• 2006

The Korean peninsula has been considered as seismically intermediate region, since seismic activities have not been severe for long time and the active tectonic boundary is also located far away. However, the activities of earthquakes have been increased significantly for last decade. Since currently important structures and facilities are increasing rapidly in the Korean Peninsula, the importance of seismic design are increasing exponentially too. This study used observed ground motion of Fukuoka event including 11 afterschocks and then estimated seismic parameters representing seismic source, propagation effect, considering site amplification. The results were comparable to those of other studies in the same region. The results could be used as basic important parameters for seismic design of the important structures and facilities in Korean peninsula.

• Journal of Mushroom
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• v.15 no.1
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• pp.57-60
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• 2017

In this study, we attempted to find alternative materials to rice bran (Japonica in Korea) such as rice bran pellet (Indica in Pakistan), corn distillers dried grains with solubles, sesame oil meal, and kapok meal for bottle cultivation of Pleurotus eryngii. Among all treatments, the total carbon content of the mixed substrate was the highest in T1 and the total nitrogen content was the highest in T4. The C/N ratio of T2 was comparable to that of the control and was higher than that of other treatments. The diameter of the pileus was the largest in T1 and T2, and the length of the stipe was the largest in T1 and T2. The yield and bio-efficiency of the fruit body were higher in T2 than in the other treatments, and were similar to that of the control plot. Therefore, the findings of our study suggest that rice bran pellet (Indica in Pakistan) could be a suitable alternative to rice bran (Japonica in Korea) for the cultivation of P. eryngii.

• Journal of Korea Water Resources Association
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• v.42 no.9
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• pp.681-690
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• 2009

In this research, design precipitation was calculated by reflecting the climatic indices and its uncertainty assessment was evaluated. Climatic indices used the sea surface temperature and moisture index which observed globally. The correlation coefficients were calculated between the annual maximum precipitation and the climatic indices. and then climatic indices which have the larger correlation coefficient were selected. Therefore, the regression relationship was established by a locally weighted polynomial regression. Next, climatic indices were generated by montecarlo simulation using kernel function. Finally, the design rainfall was calculated by the locally weighted polynomial regression using generated climatic indices. At the result, the comparison of design rainfall between the reflection of the climatic indices and the frequency analysis did not indicate a significant difference. Also, this result can be used as basic data for calculation of probability precipitation to reflect climate change.

• KSBB Journal
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• v.25 no.1
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• pp.79-84
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• 2010

In the present study, we isolated a new bacterial strain producing invertase (EC 3.2.1.26) and determined optimized culture condition in flask culture. The strain was identified as Bacilus flexus determined by the 16S rDNA sequencing method. The invertase was produced only in the sucrose medium as the sole carbon source. Potassium nitrate was an adequate nitrogen source for enzyme production, whereas meat peptone showed the highest bacterial growth. Enzyme production was increased about 2-fold when $MgSO_4\cdot7H_2O$ was supplemented to the growth media. The optimum temperature was found to be $30^{\circ}C$ for both enzyme production and bacterial growth. Invertase exhibited pH optima in the range 5.0-6.0 and have a temperature optimum at $40^{\circ}C$, similarly to other invertases found from different microbial sources. Several mineral ions (K and Fe) stimulated the invertase activity, whereas some bioelements (Ag, Mg, and Mn) inhibited enzyme activity. Under the optimized culture condition, the maximum enzyme production (over 250 units/mL) was achieved at 20 h. To the best of our knowledge, this is the first time to report on invertase production by Bacilus flexus.

• Restorative Dentistry and Endodontics
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• v.11 no.1
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• pp.63-75
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• 1985

This study was designed to identify lymphocytes and to compare the lymphocyte distribution in endoodontically treated periapical lesions with that in endodontically untreated periapical lesions by way of immunohistochemical staining. Twenty-one human dental periapical lesions were obtained, frozened, serially sectioned to $4-5{\mu}$, and stained using the three-stage indirect immunoperoxidase technique and monoclonal antibodies for detecting the presence of B,T lymphocyte and T suppressor cell. Following results were obtained; 1. All of the examined periapical lesions had positive staining for B,T lymphocyte and T suppressor cell. 2. The concentration of T lymphocytes in 18 lesions diagnosed as periapical cyst and granuloma in both groups was greater than that of B lymphocytes and 2 periapical lesions identified as abscess in treated lesions had more positive B lymphocytes than positive T lymphocytes. 3. The average numbers of T,B lymphocytes and T suppressor cells in Endodontically treated lesions were lower than those of untreated lesions, but no statistically significant difference was noted. 4. When the distribution ratios of T lymphocytes to B lymphocytes and T suppressor cells to T lymphocytes were compared in Endodontically treated lesions by the histological aspects of the lesions and at the intervals of the duration after Endodontic treatment, a statistically significant change was not found. 5. The mean values of T lymphocytes, B lymphocytes and T suppressor cells in Endodontically treated lesions were markedly decreased in the specimens obtained at 3 month after Endodontic treatment, but no statistically significant difference was found.

• Restorative Dentistry and Endodontics
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• v.27 no.5
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• pp.530-534
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• 2002

최근 치근단 와동 형성 시 초음파 또는 음파 기구를 이용하는 것이 보편화되어 있고 여러 측면에서 평가되어져 왔다. 본 연구의 목적은 혐기성 세균을 이용한 미세 누출 모델을 이용하여 초음파와 음파 기구를 사용, 치근단 와동 형성을 하였을 때 두 기구의 사용이 충전된 치근단 와동의 미세 누출에 미치는 영향을 비교 평가하는 것이다. 48개의 단근치의 근관을 crown-down방법을 이용 Profile로 .06 black까지 근관 성형을 시행하고 수직 가압법을 사용하여 gutta-percha와 AH26 sealer를 이용하여 근관 충전을 시행하였다. 각 충전된 시편의 치근단 3mm를 절제하였다. 각 시편은 이미로 4군으로 나누었으며 1군에서는 치근단 와동을 초음파 기구로 형성하였고 2군에서는 음파 기구로 형성하였다. 3군은 음성대조군으로 4군은 양성대조군으로 분류하였다. 형성된 치근단 와동은 공기 분사침을 이용하여 건조 후 super EBA 시멘트로 충전하였으며 Anaerobic chamber에서 Fusobacterium nucleatum (VPI 10197)을 사용한 혐기성 세균 미세누출 모델을 이용하여 30일간 미세 누출을 관찰한 결과, 초음파 기구를 사용한 군에서는 80%에서 음파 기구를 사용한 군에서는 75%에서 미세누출이 나타났으나 통계적으로 유의성 있는 차이는 보이지 않았다.