• The Korean Publising Journal, Monthly
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• s.376
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• pp.84-85
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• 2007

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.10a
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• pp.16-16
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• 2017

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.155-156
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• 2002

관성임팩터(inertial impactor)는 입자의 관성을 이용하여 기류로부터 입자를 분리하는 장치이며 입자를 입경별로 포집하는데에 높은 효율을 가지며 작동하기에 간편하므로 널리 사용되고 있다. 하지만, 임팩터는 입자의 되튀김(bouncing), 재유입(reentrainment), 그리고 과적(overload)과 같은 입자와 충돌판의 상호작용에 의한 문제점이 있다. 일반적으로 이런 문제점을 해결하기 위해서는 충돌판의 표면에 그리스(grease) 또는 오일(oil)을 코팅하여 사용하는 방법이 있다. (중략)

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.408-411
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• 2015

Trilayer graphene에 비활성기체 중 하나인 Ne 원자가 어떤 영향을 미치는지에 대해 density functional theory calculation을 이용해서 연구하였다. ABA stacked trilayer graphene의 $4{\times}4$ super cell에서 top surface에 adsorption되는 경우와 trilayer 내부에 intercalation 되는 경우에 대하여 energy를 계산하여 Ne 원자들의 안정한 위치를 찾았다. Adsorption의 경우 hollow site가 가장 안정하였고 intercalation의 경우에도 top layer의 hollow site의 아래가 가장 안정하였다. 또한 Ne 원자 2개가 adsorption되는 경우의 adsorption energy를 통하여 Ne 원자들 사이의 상호작용을 예측하였다.

• Proceedings of the Ginseng society Conference
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• 1998.05a
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• pp.38-38
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• 1998

• Journal of the Korean institute of surface engineering
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• v.24 no.1
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• pp.16-16
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• 1991

Generally brittle eta phase produced during TiC deposition has a effect on the TRS (transverse rupture strength ; thoughness). Therefore it is necessary to reduce eta(η), phase for the improvement of tool life. At this experiment some properties (TRS, bonding strength, tool life, eta phase)have been investigated by inserting TiN or TiCN underlayer between TiC layer and substrate. The results obtained were as follows; 1. by inserting underlayer eta phase were decreased and TRS was increased, but the bonding strength was decreased. 2. the diffusion of W, Co from the substrate was hindered by the underlayer. 3. TiC layer with TiCN underlayer had the finsest grain size. 4. by inserting underlayer (TiCN or TiN) the tool life was improved and especially notch and crater wear resistance was greatly improved.

• Journal of the Korean earth science society
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• v.34 no.1
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• pp.13-27
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• 2013

Quantitative precipitation estimation (QPE) is one of the most important elements in meteorological and hydrological applications. In this study, we adjusted the QPE from an S-band weather radar based on co-kriging method using the geostatistical structure function of error distribution of radar rainrate. In order to estimate the accurate quantitative precipitation, the error of radar rainrate which is a primary variable of co-kriging was determined by the difference of rain rates from rain gauge and radar. Also, the gauge rainfield, a secondary variable of co-kriging is derived from the ordinary kriging based on raingauge network. The error distribution of radar rain rate was produced by co-kriging with the derived theoretical variogram determined by experimental variogram. The error of radar rain rate was then applied to the radar estimated precipitation field. Locally heavy rainfall case during 6-7 July 2009 is chosen to verify this study. Correlation between adjusted one-hour radar rainfall accumulation and rain gauge rainfall accumulation improved from 0.55 to 0.84 when compared to prior adjustment of radar error with the adjustment of root mean square error from 7.45 to 3.93 mm.

• Journal of the Korean earth science society
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• v.35 no.2
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• pp.115-130
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• 2014

The growing possibility of the disaster due to severe weather calls for disaster prevention and water management measures in South Korea. In order to prevent a localized heavy rain from occurring, the rainfall must be observed and predicted quantitatively. In this study, we developed an adjustment algorithm to estimate the radar precipitation applying to the local gauge correction (LGC) method which uses geostatistical effective radius of errors of the radar precipitation. The effective radius was determined from the errors of radar rainfall using geostatistical method, and we adjusted radar precipitation for four heavy rainfall events based on the LGC method. Errors were decreased by about 40% and 60% in adjusted hourly rainfall accumulation and adjusted total rainfall accumulation for four heavy rainfall events, respectively. To estimate radar precipitation for localized heavy rain events in summer, therefore, we believe that it was appropriate for this study to use an adjustment algorithm, developed herein.

• Korean Journal of Microbiology
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• v.53 no.3
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• pp.208-215
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• 2017

A cyclomaltodextrinase (SPCD) gene was cloned from Streptococcus pyogenes ATCC 700294. Its open reading frame consists of 567 amino acids (66.8 kDa), which shows less than 37% of amino acid sequence identity with the other CDase-family enzymes. The homo-dimeric SPCD with C-terminal six-histidines was expressed and purified from Escherichia coli. It showed the highest activity at pH 7.5 and $45^{\circ}C$, respectively. SPCD has the broad substrate specificities against ${\beta}$-cyclodextrin, starch, and maltotriose to produce mainly maltose, whereas it hydrolyzes pullulan to panose. It can also catalyze the hydrolysis of acarbose to glucose and acarviosine-glucose. Interestingly, it showed much higher activity on ${\beta}$-cyclodextrin and acarbose than that on starch, pullulan, or maltotriose, which makes SPCD distinguished from common CDase-family enzymes. Although SPCD has significantly high acarbose-hydrolyzing activity, it showed negligible transglycosylation activity.

• Journal of the Korean earth science society
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• v.38 no.7
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• pp.496-510
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• 2017

This study presents a new nationwide quantitative precipitation estimation (QPE) based on the hybrid surface rainfall (HSR) technique using the weather radar network of Korea Meteorological Administration (KMA). This new nationwide HSR is characterized by the synthesis of reflectivity at the hybrid surface that is not affected by ground clutter, beam blockage, non-meteorological echoes, and bright band. The nationwide HSR is classified into static (STATIC) and dynamic HSR (DYNAMIC) mosaic depending on employing a quality control process, which is based on the fuzzy logic approach for single-polarization radar and the spatial texture technique for dual-polarization radar. The STATIC and DYNAMIC were evaluated by comparing with official and operational radar rainfall mosaic (MOSAIC) of KMA for 10 rainfall events from May to October 2014. The correlation coefficients within the block region of STATIC, DYNAMIC and MOSAIC are 0.52, 0.78, and 0.69, respectively, and their mean relative errors are 34.08, 30.08, and 40.71%.