• 대한원격탐사학회지
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• 제38권4호
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• pp.343-353
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• 2022

An attempt to derive the surface temperature from the Korea Multi-purpose Satellite (KOMPSAT)-3A mid-wave infrared (MWIR) data acquired over the southern California on Nov. 14, 2015 has been made using the MODerate resolution atmospheric TRANsmission (MODTRAN) radiative transfer model. Since after the successful launch on March 25, 2015, the KOMPSAT-3A spacecraft and its two payload instruments - the high-resolution multispectral optical sensor and the scanner infrared imaging system (SIIS) - continue to operate properly. SIIS uses the MWIR spectral band of 3.3-5.2 ㎛ for data acquisition. As input data for the realistic simulation of the KOMPSAT-3A SIIS imaging conditions in the MODTRAN model, we used the National Centers for Environmental Prediction (NCEP) atmospheric profiles, the KOMPSAT-3Asensor response function, the solar and line-of-sight geometry, and the University of Wisconsin emissivity database. The land cover type of the study area includes water,sand, and agricultural (vegetated) land located in the southern California. Results of surface temperature showed the reasonable geographical pattern over water, sand, and agricultural land. It is however worthwhile to note that the surface temperature pattern does not resemble the top-of-atmosphere (TOA) radiance counterpart. This is because MWIR TOA radiances consist of both shortwave (0.2-5 ㎛) and longwave (5-50 ㎛) components and the surface temperature depends solely upon the surface emitted radiance of longwave components. We found in our case that the shortwave surface reflection primarily causes the difference of geographical pattern between surface temperature and TOA radiance. Validation of the surface temperature for this study is practically difficult to perform due to the lack of ground truth data. We therefore made simple comparisons with two datasets over Salton Sea: National Aeronautics and Space Administration (NASA) Jet Propulsion Laboratory (JPL) field data and Salton Sea data. The current estimate differs with these datasets by 2.2 K and 1.4 K, respectively, though it seems not possible to quantify factors causing such differences.

• Journal of Microbiology and Biotechnology
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• 제22권9호
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• pp.1288-1295
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• 2012

Exposure to bioaerosols causes various adverse health effects including infectious and respiratory diseases, and hypersensitivity. Controlling exposure to bioaerosols is important for disease control and prevention. In this study, we evaluated the efficacies of various functional filters coated with antimicrobial chemicals in deactivating representative microorganisms on filters or as bioaerosols. Tested functional filters were coated with different chemicals that included (i) Ginkgo and sumac, (ii) Ag-apatite and guanidine phosphate, (iii) $SiO_2$, ZnO, and $Al_2O_3$, and (iv) zeolite. To evaluate the filters, we used a model ventilation system (1) to evaluate the removal efficiency of bacteria (Escherichia coli and Legionella pneumophila), bacterial spores (Bacillus subtilis spore), and viruses (MS2 bacteriophage) on various functional filters, and (2) to characterize the removal efficiency of these bioaerosols. All experiments were performed at a constant temperature of $25^{\circ}C$ and humidity of 50%. Most bacteria (excluding B. subtilis) rapidly decreased on the functional filter. Therefore, we confirmed that functional filters have antimicrobial effects. Additionally, we evaluated the removal efficiency of various bioaerosols by these filters. We used a six-jet collision nebulizer to generate microbial aerosols and introduced it into the environmental chamber. We then measured the removal efficiency of functional filters with and without a medium-efficiency filter. Most bioaerosol concentrations did not significantly decrease by the functional filter only but decreased by a combination of functional and medium-efficiency filter. In conclusion, functional filters could facilitate biological removal of various bioaerosols, but physical removal of these by functional was minimal. Proper use of chemical-coated filter materials could reduce exposure to these agents.

• 대한조선학회논문집
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• 제36권4호
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• pp.21-27
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• 1999

본 논문에서는 교란 포텐셜을 기저로 하는 패널방법을 사용하여 물제트를 분사하는 플랩을 가진 타의 성능해석을 수행하였다. 받음각이 큰 경우, 성능해석의 주요 인자가 되는 후류면의 위치를 구하기 위하여 후류면의 roll-up을 포함시킨 Pyo[1]의 방법을 사용하여 계산하였고, 경계면은 쌍곡면 패널로 이산화하였다. 플랩타의 본체와 플랩 사이의 간극유동을 점성유동인 Couette유동으로 가정하여 계산하였고, 간극 사이에서 분사되는 물제트는 유량변화를 소스로, 모멘텀변화를 떨어져 나가는 보오텍스로 가정하여, 간극의 입구와 출구 패널 위에서 경계조건으로 포함시켜 계산하였다. 본 방법의 수치적 검증을 위해 실험값이 존재하는 경우에 대해 실험값과 프로그램의 수치결과를 비교하였다. 비교 결과, 실험값은 계산값과 좋은 일치를 보임을 확인하였다.

• 한국화재소방학회논문지
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• 제31권4호
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• pp.20-25
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• 2017

본 연구에서는 화염 내에 생성된 그을음 입자가 방사하는 복사 강도 분포를 측정하고, 이를 바탕으로 Jet A1 액적확산 화염의 온도 분포를 예측하였다. 이를 위해서 700 nm와 900 nm 각각의 파장에 대해서 화염 내 그을음 입자가 방사하는 복사 강도를 CCD 카메라로 측정하였고 Abel 변환을 통해 얻어진 국소 복사 강도 분포를 이색법(Two Color Method)에 적용하여 최종 화염의 온도 분포를 계산하였다. 그 결과 이색법에 의한 측정은 그을음의 복사 강도와 투영된 시각선의 간격에 따라서 약 2% 정도 이내의 deconvolution 오차가 발생할 수 있으며, 본 연구 결과에서 제시한 측정 방법을 통해 2000 K 기준 약 18 K 오차 범위 이내에서 화염온도 예측이 가능함을 확인하였다.

• 암석학회지
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• 제1권2호
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• pp.91-103
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• 1992

Eruptive mechanisms and processes at Udo tuff cone can be inferred from indicative characters of products, bedforms and lithofacies, and ring faults. In terms of bedforms and lithofa-cies in particular, massive lapilli tuff beds and chaotic lapilli tuff beds are derived from subaerial falls of aggregated tephra of wet tephra finger jets, occurring dominantly at the lower sequences of proximal part at the tuff cone. Crudely stratified lapilli tuff are derived from subaerial falls of slightly aggregated tephra of less wet tephra finger jets, whereas reversely graded lapilli tuff beds are from slightly disaggregated subaerial falls of continuous uprush. Both beds frequently occur in the middle sequences at proximal and near medial part of the tuff cone. Block and lapilli tephra lenses, ash-coated lapilli tephra beds(lenses) and thin-bedded tuff beds are derived from extremely disaggregated subaerial falls of dry tephra in the continuous uprush, frequently occurring at the upper sequences of medial part at the tuff cone. Udo tuff cone is a basaltic volcano emergent through the sea water surface while water could flood across or into the vent area. Emergence of the tuff cone was from the type-Surtseyan eruption characterized by earlier tephra finger jets and later continuous uprush columns of tephra with copious volumes of steam. Explosions began when boiling of wter produced a bubble column reducing the hydrostatic pres-sure, allowing exsolution of gases from the magma. This expansion of magma into a vesiculating froth fragmented the magma and permitted mixing of magma and water so that a more vigorous generation of steam could proceed. Tephra finger jetting explosions continued to build the crater rims, then remove water from the vent that their deposits flowed like slsurries until the continuous uprush explosion ensued. Continuous uprush explosions were associated with most rapid accumula-tion of tephra. The increasing volume rate led to partial removal of water from the vent area by the newly tephra ring so that more vigorous activity could be attended by a reducing water supply. This might restrain surplus of cold water entering the vent and thus enhance the vigour of the eruption by allowing optimal heat exchange. Eventually the crater became so deep and unsuported that piecemeal sliding, or massive subsidence on indipping ring faults, filled and closed the vent, and the cycle of explosions and collapse began anew.

• Nuclear Engineering and Technology
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• 제55권1호
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• pp.169-179
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• 2023

Filtered containment system is a passive safety system that controls the over-pressurization of containment in case of a design-based accidents by venting high pressure gaseous mixture, consisting of air, steam and radioactive particulate and gases like iodine, via a scrubbing system. An indigenous lab scale facility was developed for research on iodine removal by venturi scrubber by simulating the accidental scenario. A mixture of 0.2 % sodium thiosulphate and 0.5 % sodium hydroxide, was used in scrubbing column. A modified mathematical model was presented for iodine removal in venturi scrubber. Improvement in model was made by addition of important parameters like jet penetration length, bubble rise velocity and gas holdup which were not considered previously. Experiments were performed by varying hydrodynamic parameters like liquid level height and gas flow rates to see their effect on removal efficiency of iodine. Gas holdup was also measured for various liquid level heights and gas flowrates. Removal efficiency increased with increase in liquid level height and gas flowrate up to an optimum point beyond that efficiency was decreased. Experimental results of removal efficiency were compared with the predicted results, and they were found to be in good agreement. Maximum removal efficiency of 99.8% was obtained.

• 한국수정란이식학회지
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• 제31권4호
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• pp.335-347
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• 2016

Multiple interferon tau (IFNT) genes exist in bovine. An antiluteolytic substance secreted by the bovine conceptus and primarily responsible for maternal recognition of pregnancy is bovine trophoblast protein 1 (bIFNT1), a new type I interferon tau (IFNT) genes. The objectives of this research were to investigate whether multiple, distinct gene encode bIFNT1 and other type I bIFNT gene in the bovine genome and to examine expression of bIFNT1 and other bIFNTc1 mRNAs during conceptus development. These transcrips could be regulated through caudal-related homeobox-2 (CDX2) and ETS2 and/or AP1 (JUN) expression, a transcription factor implicated in the control of cell differentiation in the trophectoderm. The presence of mRNAs encoded by bIFNT1 and type I bIFNTc1 genes were examined quantitatively via reverse transcription-polymerase chain reaction (RT-PCR) analysis of total cellular RNA (tcRNA) extracted from on day 17, 20 and 22 bovine conceptuses. The expression level of bIFNT1 was higher on day 17 transcripts were gradually weakly detectable on day 20 and 22. However, the other bIFNTc1 gene examined transcripts was highly expressed on day 20 and transcripts were weakly detectable on day 17 and 22 bovine conceptuses. Furthermore, human choriocarcinoma JEG3 was co-transfected with an -1kb-bIFNT1/c1-Luc constructs and several transcription factor expression plasmids. Compared to each -1kb-bIFNT1/c1-Luc increased when this constructs were co-transfected with, ETS2, AP1(JUN), CREBBP and/or CDX2. Also, bIFNTc1 gene was had very effect on activity by alone ETS2, and AP1 (JUN) expression factors in choriocarcinoma JEG3 cell. However, bIFNT1 gene expression of the upstream region was not identified. We demonstrated that the activities of bIFN genes are regulated by differential, tissue-specific and developmental competence during pregnancy.

• 한국수정란이식학회지
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• 제28권3호
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• pp.215-222
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• 2013

Bovine coat color is decided by the melanocortin receptor 1 (MC1R) genotype mutation and melanogenesis. Specially, in the various cattle breeds, dominant black coat color is expressed by dominant genotype of $E^D$, red or brown is expressed in the frame shift mutation of recessive homozygous e by base pair deletion and wild type of $E^+$ is expressed in various coat colors. However, not very well known about the effected of MC1R genotype mutation on the coat color through family lines in KBC. Therefore, this study were to investigate effect of MC1R genotype mutation on the coat color, and to suggest mating breed system in accordance with of MC1R genotype for increased on brindle coat color appearance. Parents (sire 2 heads and dam 3 heads) and offspring (total : 54 heads) from crossbreeding in KBC family line with the MC1R genotype and phenotype records were selected as experimental animals. The relationship between melanocortin 1 receptor (MC1R) genotypes expression verified by PCR-RFLP, and brindle coat color appearance to the family line of the cross mating breed from MC1R genotype pattern was determined. As a result, 4MC1R genetic variations, $E^+/E^+$ (sire 1), $E^+/e$ (sire 2 and dam 3), $E^+/e$ with 4 bands of 174, 207 and 328 bp (dam 1) and $E^+/e$ with 3 bands of 174, 207, 328 and 535 bp (dam 2) from parents (sire and dam) of KBC. However, 3 genetic variations, e/e (24%), $E^+/E^+$ (22%) and $E^+/e$ (56%) were identified in offspring. Also, brindle coat color expressrated was the e/e with the 0%, $E^+/E^+$ with 67% and $E^+/e$ with 77% from MC1R genotype in offspring on the cross mating of KBC. Furthermore, when the sire had $E^+/e$ genotype and the dam had $E^+/E^+$ with the 3 bands or $E^+/e$ genotype, and both had whole body-brindle coat color, 62% of the offspring had whole body-brindle coat color. Therefore, the seresults, the mating system from MC1R genotype patterns of the sires ($E^+/e$) and dams ($E^+/E^+$ with the 3 bands or $E^+/e$) with brindle coat color may have the highest whole body-brindle coat color expression in their offspring.

• 한국수정란이식학회지
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• 제31권3호
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• pp.185-190
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• 2016

During the ovary preservation in low temperature, the cumulus oocyte complexes(COCs) lose their developmental competences after in vitro fertilization. We used phosphate-buffered saline (PBS) as a basic solutions of at various temperatures (25, 15 or $5^{\circ}C$) and supplemented them with 1mM glucose and 0.5mM glutamine as a source of carbohydrate metabolites. After recovery of COCs and in vitro fertilization, a significantly higher number of oocytes developed into blastocysts. The developmental competence of embryos that were originated from ovaries preserved at $15^{\circ}C$ was increased compared to those of 25 or $5^{\circ}C$. The maturation rate of oocytes was not differed between 24 and 36 h at $15^{\circ}C$ but showed lower than control group (71% versus 78%). In vitro-fertilized oocytes from ovaries stored at $25^{\circ}C$ for 24 h or at $5^{\circ}C$ for 24 h had a significantly decreased developmental potentials, but at $15^{\circ}C$ did not (27% versus 29% of blastocysts to develop into day 8). With these results, bovine ovaries can be preserved at $15^{\circ}C$ for 36 h without decreasing developmental capacity of in vitro-fertilized oocyte at least to the blastocyst stage. This information provides valuable information of preserving ovaries for embryo transfer or in vitro embryo production.

• 한국항해항만학회지
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• 제28권3호
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• pp.259-268
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• 2004

지난 몇 년 동안, 해안지역에서 산업의 발달과 인구증가로 인해서 육지에서 방출되는 오폐수의 정화 처리 방법이 중요한 문제점으로 지적되고 있다. 처리방법으로는, 1차 처리 또는 2차 처리된 것을 수중 방류관을 통해 해안이나 심해 또는, 그 중간지점에서 방출되는데, 오폐수가 방출되면 주변의 해수를 연행하여 플룸, 제트 또는 부양성 제트의 형태로 해수면까지 상승하면서 많이 희석된다. 본 연구는 해양환경관리 및 오폐수 처리에 관한 의사결정과정에서 중요한 해양방류관 설계를 다룬다. Cormix 모델에 조위의 변화와 계절변화에 의한 몇가지 요소를 고려하여 방류수의 궤적과 희석을 다룬다. 본 연구는 방류수의 효과석인 관리를 위한 기본 데이터와 일반배치에 매우 유용하게 활용될 것이다.