• Nuclear Engineering and Technology
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• v.19 no.3
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• pp.198-204
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• 1987

A plant simulation code, MCSIM (Micro-Computer SIMulator), has been developed to simulate plant transient accidents for pressurized water reactors. Reactor coolant system is modeled using decoupled energy and momentum equations, drift flux two-phase flow model and integral momentum equation. A two-fluid pressurizer model is used to simulate the pressurizer dynamics. Pot Boiler model is used for steam generator, steady-state decoupled energy and momentum equations for secondary side system, and point kinetics equations for nuclear power calculation. For test of the present version of MCSIM, complete loss of flow and RCCA withdrawal accidents are calculated with MCSIM. The results are compared with those in FSAR of KNU 5 & 6.

• Current Research on Agriculture and Life Sciences
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• v.9
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• pp.29-36
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• 1991

The study was carried out to investigate the viability and the offspring production rate of single blastomeres and biopsied 4-cell mouse embryos and, also to examine the efficiency of biopsy. The results obtained are summerised as follows: 1. The separated blastomeres from 4-cell embryos and intact 4-cell embryos which were cultured in Medium 2 were developed to trophoblastic vesicle and blastocyst embryo by 82.6% and 89.5%. respectively. 2. The biopsied embryos from 4-cell embryos and intact 4-cell embryos which were cultured in Medium 2 were developed to blastocyst embryo by 83.3% and 90.4%, respectively. 3. The biospied blastomeres and the separated blastomeres from 4-cell embryos which were cultured in Medium 2 were developed to trophoblastic vesicle by 80.8% and 83.3%, respectively. 4. The biopsied embryos from 4-cell embryos and intact 4-cell embryos were transferred to recipients, and the offspring rate was 36% and 48.6%, respectively.

• Microbiology and Biotechnology Letters
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• v.41 no.4
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• pp.383-390
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• 2013

Several yeasts were isolated from flowers found in Gyonggi-do Province and Jeju island in Korea. They were then identified by a comparison of their PCR-amplified D1/D2 regions of 26S rDNA, internal transcribed spacer 1 and 2 inclusive of 5.8S rDNA, using the BLAST database. A total of fifty four yeast strains were isolated from wild flowers in Gyonggi-do and the genus Pseudozyma was noted as being dominant. A total of thirty two strains were isolated from Songaksan and Seongsan-ilchulbong in Jeju island and Sporobolomyces ruberrimus was seen to be dominant. The anti-gout xanthine oxidase inhibitory activities of the culture broths and cell-free extracts from eighty six yeast strains were then determined. The cell-free extracts of Pseudozyma hubeiensis 228-S-1 exhibited the highest xanthine oxidase inhibitory activity of 19.6%. The XOD inhibitor was also maximally produced when Pseudozyma hubeiensis 228-S-1 was cultured at $30^{\circ}C$ for 36h in YEPD medium.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.37-37
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• 2003

본 연구실에서는 체세포복제 수정란 이식우의 분만전후 태아와 모체 및 태반과의 내분비적인 관계를 검토하기 위해 복제수정란 이식우의 분만 전후에 있어서, 혈중progesterone 과 TGF-$\beta$$_1$ 수준을 분석한 결과 정상우의 분만직전과 달리 혈중progesterone 및 TGF-$\beta$$_1$ 농도는 감소되지 않고 높은 수준을 그대로 유지되어 복제수정란이식우의 경우 정상적인 분만 signal이 나타나지 않는 것으로 나타났다. 본 연구는 체세포 복제소 수정란 이식우에 있어서 태반조직의 특성을 정상우의 동일한 시기의 태반과 비교 검토하였으며 분만시기에 있어서 태반의 역할을 검토하였다. 태반은 복제란 이식우 및 정상우 임신우를 술을 실시하여 태반을 채취하여 실험에 공시하였다. 정상우의 임신기간중 혈중 progesterone 농도는 임신초기와 중기에 다소 증가되어 유지되다가 임신말기에는 급격한 progesterone의 감소현상과 더불어 분만이 유기되는 것으로 나타났으나 복제우의 경우 분만예정일 직전까지 progesterone의 급격한 감소는 일어나지 않고 높은 농도로 유지되는 현상을 보였다. 이때 제왕절제 수술중 제대근방에 있는 태반궁부를 적출하여 중량을 측정한 결과 정상우의 궁부에 비해 유의적으로 무거웠으며, 이것은 태아의 중량과 정의 상관관계가 있음이 확인되었으며 태아 및 궁부의 중량이 무거울수록 분만 전후의 태아사망율이 높은 것으로 나타났다 이때의 궁부를 조직학적으로 검토한 결과, 복제우의 태반궁부는 정상우의 궁부에 비해 cytotrophoblast 및 syncytiotrophoblast가 적었으며 치밀하지 못한 형태를 확인할 수 있었다. 이때의 태반조직를 이용하여 세포질을 추출하여 단백질양상을 검토한 결과, 정상태반에 비해 복제태반은분자량 90kd, 65kd 및 18kd의 특이단백질이 존재하고 있음을 확인할 수 있었으며 이들 단백질을 HPLC system에 의해 분리한 결과 fraction 2와 3에서 특이한 단백질을 분리하였다. 이와 같이, 복제우의 태반에는 정상적인 임신과 분만을 비롯하여 복제송아지의 생존에 중요한 인자가 관여하고 있을 확인할 수 있었다.

• Analytical Science and Technology
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• v.12 no.1
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• pp.47-52
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• 1999

Antifungal substances were isolated and identified from garlic and taxus extracts to develop safe and broad fungicide. The inhibitory effect of seedborn disease of sesame, pepper, radish, chinese cabbage by formulation of antifungal substances was investigated. The antifungal substance isolated through column chromatography from garlic and taxus extracts was confirmed by GC-MS as allicin($C_6H_{10}OS_2$) and taxol($C_{47}H_{51}NO_{14}$) and the quantified content from each extracts by HPLC analysis was 0.62%, 0.29%, respectively. The formulation composed of garlic and taxus extracts controlled effectively the seedborn fungi tested in this study at 10X dilution, but at 100X dilution the inhibitory effect decreased. Phytotoxicity of these formulations did not recognized.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.953-957
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• 2002

Volatile compounds from shrimp whole body (SWB) and shrimp shell waste (SSW) were isolated, and identified by the combination of SDE (simultaneous steam distillation and solvent extraction), GC (gas chromatography, HP-5890 plus)and MSD (mass selective detecter) or olfactometry. The peak numbers isolated from SWB and SSW were 20 and 46, respectively. The amounts of the volatile compounds isolated from SSW were higher than those of SWB. SWB produced more low-boiling compounds below 7$0^{\circ}C$ and SSW did more high boiling compounds over 10$0^{\circ}C$. The volatile compounds identified from SSW were 9 pyrazines,5 acids,4 aldehydes, and 4 alcohols. These volatile compounds were evaluated by aroma extraction dilution analysis and gas chromatography olfactometry (GCO). Some compounds which were not detected by GC-FID and GC-MSD were found to be a strong shrimp flavor of log$_3$ FD 3 value by GCO. Strong shrimp odors were detected in low temperature while nutty aromatic odors and unpleasant oily smells were found in high temperature.

• Korean Journal of Veterinary Service
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• v.14 no.2
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• pp.143-147
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• 1991

Between June and August 1990, the tonsils of 86 healthy pigs were examined for the presence of staphylococci. All of the pigs examined harboured Staphylococci in the tonsils, the most predominant Staphylococcus species was Staphylococcus aureus(45.3%) followed by Staph hyicus subsp chromogenes (20.9%), Staph hyicus subsp hyicus (16.3%), Staph hominis(4.7%), Staph simulans(2.3%) and Staph xylosus(1.2%), Unidentifiable species were isolated from 3(3.5%) of the 86 tonsils examined. Thirty-nine strains of Staph aureus were subjected to the biotyping scheme of Hajek & Marsalek all the strains were classified as biotype B.

• Corrosion Science and Technology
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• v.13 no.6
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• pp.224-232
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• 2014

Effect of pretreatments on the graphene coated bipolar plate of proton exchange membrane fuel cell(PEMFC) was investigated in simulated environments for PEMFC by using electrochemical measurement techniques. Interfacial contact resistance(ICR) between the graphene coated bipolar plate and the gas diffusion layer(GDL) was measured. The value of ICR decreased with an increase in compaction stress($20N/cm^2{\sim}220N/cm^2$). ICR of graphene coated bipolar plate was higher than that of bare 316L stainless steel. However, Potentiodynamic measurement results showed that the corrosion resistance of graphene coated bipolar plate was higher than that of bare 316L stainless steel. $H_2SO_4$ acid pretreatment was the most effective among various pretreatments. The lowest ICR and the corrosion current density were obtained when using $H_2SO_4$ solution pretreatment.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.1242-1246
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• 2004

본 연구에서는 유속계와 봉부자를 동한 측정값의 불확실성를 검토한 후, 한강의 7개 지류의 실측 자료들의 불확실성을 ISO 규정을 통하여 추정하였다. Simulated Annealing 기법과 황금비 분할법을 이용한 비선형회귀식을 적용하여 기존의 수위-유량 곡선식자 비교해보았다. 불확실성 추정결과 유량 측정치들의 불확실성이 ISO 규정의 기준에 비해 높게 추정되었으며, 특히 무작위 오차와 계통 오차 중에 무작위 오차의 불착실성이 높게 나타났다. 또한, 기존 수위-유량곡선식과 Simulated Annealing 기법과 황금비 분할법을 이용한 방법을 비교해본 결과 황금비 분할법이 가장 좋은 결과를 얻었다. 이때 수위-유량곡선식의 영수위값을 황금비 분할법을 이용해 구한 후 비교해 본 결과는 기존의 선형회귀방법과 비선형방법에서 큰 차이를 보이지 않았다. 또한 곡선 분리시에는 하나의 수위-유량곡선일때보다 오차가 줄어드는 경향을 보였다.

• 한국공간정보시스템학회:학술대회논문집
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• 2000.06a
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• pp.23-34
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• 2000

최근 네트웍의 보급과 지리정보의 활용이 증가하면서 효과적인 지리정보의 교환과 접근에 대한 중요성이 강조되고 있다. 하지만 기존의 GIS 데이터는 지리적으로 분리된 여러 부서나 조직에서 생성되고 있으며, 공간 정보 유통을 위한 클리어링하우스 등이 서로 다른 DBMS 상에서 독자적인 스키마를 가지고 개발되어 있다. 이러한 이질적인 구조와 구현 환경으로 인해 일반 사용자들이 서로 다른 GIS 데이터베이스를 접근하여 검색하는데 많은 어려움이 따르고 있다. 본 연구에서는 OMG의 메타데이터 교환 표준인 XMI로 표현된 이질적인 GIS 데이터베이스의 메타데이터를 통하여 사용자에게 각 데이터베이스의 구현 환경과 스키마에 독립적인 공간 데이터를 검색 기능을 제공하는 검색시스템을 구현하였다.