• Journal of the Korean Magnetic Resonance Society
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• v.19 no.3
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• pp.106-111
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• 2015

Helicobacter pylori (H. pylori) survives in acidic and fluctuating pH conditions of the stomach. The pH effect on H. pylori proteins is important for the advanced understanding of its evolution and viability, although this bacterium has the molecular machinery that neutralizes the acidic condition. HP1492 is known as a conserved NifU-like protein from H. pylori. NifU is a nitrogen fixation protein that mediates the transfer of iron-sulfur (Fe-S) cluster to iron-sulfur proteins like ferredoxin. Commonly, the monomeric reduced state of NifU can be converted to the dimeric oxidized state by intermolecular disulfide bond formation. Because it remains unclear that HP1492 actually behaves as known NifU protein, we first found that this protein can adopt both oxidized and reduced forms using size exclusion chromatography. Circular dichroism experiment showed that HP1492 is relatively well-structured at pH 6.5, compared to other pH conditions. On the basis of the backbone resonance assignment of HP1492, we further characterized the residues that are sensitive to pH using NMR spectroscopy. These residues showing large chemical shift changes could be mapped onto the secondary structure of the protein. Our results could provide the foundation for structural and biophysical studies on a wide spectrum of NifU proteins.

• Journal of the Korean Mathematical Society
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• v.20 no.2
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• pp.141-161
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• 1983

• Korean Journal of Remote Sensing
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• v.36 no.5_3
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• pp.1095-1107
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• 2020

Flood monitoring using satellite data has been constrained by obtaining satellite images for flood peak and accurately extracting flooded areas from satellite data. Deep learning is a promising method for satellite image classification, yet the potential of deep learning-based flooded area extraction using SAR data remained uncertain, which has advantages in obtaining data, comparing to optical satellite data. This research explores the performance of SegNet and U-Net on image segmentation by extracting flooded areas in the Khorat basin, Mekong river basin, and Cagayan river basin in Thailand, Laos, and the Philippines from Sentinel-1 A/B satellite data. Results show that Global Accuracy, Mean IoU, and Mean BF Score of SegNet are 0.9847, 0.6016, and 0.6467 respectively, whereas those of U-Net are 0.9937, 0.7022, 0.7125. Visual interpretation shows that the classification accuracy of U-Net is higher than SegNet, but overall processing time of SegNet is around three times faster than that of U-Net. It is anticipated that the results of this research could be used when developing deep learning-based flood monitoring models and presenting fully automated flooded area extraction models.

• The Bulletin of The Korean Astronomical Society
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• v.33 no.1
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• pp.73.1-73.1
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• 2008

• Proceedings of the KAIS Fall Conference
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• 2010.05a
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• pp.235-237
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• 2010

u-City의 핵심 요소인 통합관리센터는 u-City 내의 모든 서비스를 처리하도록 설계되었으며, 도시를 통제하는 중요한 기능을 수행해야 하므로 인증 및 보안을 처리하기 위한 기술이 요구되며 이러한 기술은 통합관리센터에 필수적으로 구현되어야 한다. 본 논문에서는 u-City 인증을 위한 통합관리센터를 나타내고, 이에 대한 응용사례를 보여준다.

• American Studies
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• v.42 no.1
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• pp.57-97
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• 2019

This study seeks to reveal why the U.S. House Democrats showed different levels of support in the voting of the U.S.-Morocco FTA, U.S.-Bahrain FTA, and U.S.-Oman FTA. Existing studies focusing on the constituency or members' ideology do not properly account for the variance of these three FTA voting results. All of these FTAs, however, were promoted as a part of the president's foreign policies. If so, FTA support in Congress could depend on representatives' evaluation of the presidential foreign policy. Based on this, the study analyzes how representatives' evaluation of President Bush's foreign policy changed according to the period of the three FTA votes. The vote on the FTAs has been influenced by their evaluation of the presidential foreign and national security policies.

• The Bulletin of The Korean Astronomical Society
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• v.18
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• pp.7.2-8
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• 1993

• The Korean Journal of Nuclear Medicine
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• v.6 no.2
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• pp.41-47
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• 1972

The radioimmunoassay of human thyrotropin was performed in various thyroid states, utilizing the anti-h-T.S.H. antibody and purified human thyrotropin supplied from National Institute of Arthritis and Metabolic Diseases, Bethesda, Ma., U.S.A., and human thyrotropin standard-A obtained from National Institute for Biologic Standards, Mill Hill, London, England. $^{131}I$ labelled h-TSH was prepared after the Chloramine-T method of Greenwood et al. This double antibody system had a assay sensitivity of about $1.0{\mu}U/ml$ of plasma HTS-A and could detect the plasma h-TSH level in the euthyroid patients. Plasma h-TSH level of the normal 26 Korean was $1.1{\pm}0.83{\mu}U/ml$, and that of the 8 hypothyroidisms were 8.3 to $67.5{\mu}U/ml$. In hyperthyroidisms, no cases showed the plasma h-TSH levels over $1.0{\mu}U/ml$. Between the hypothyroidism and euthyroidsm, no overlap is noticed on plasma h-TSH levels. A case of transient hypothyroid state identified by determination of plasma h-TSH level is presented. These results revealed that the radioimmunoassay of h-TSH in plasma could be a sensitive method to diagnose the hypothyroidsm, if not caused by a pituitary disease.

• Clinical and Experimental Reproductive Medicine
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• v.40 no.2
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• pp.95-99
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• 2013

Objective: To evaluate the correlation between serum levels of anti-M$\ddot{u}$llerian hormone (AMH) and ovarian response to mild stimulation in normoovulatory women and anovulatory women with polycystic ovary syndrome (PCOS). Methods: Seventy-four cycles of mild stimulation (clomiphene citrate+gonadotropin followed by timed intercourse or intrauterine insemination) performed in normoovulatory women (57 cycles) and anovulatory women with PCOS (17 cycles). Ovarian sensitivity was defined by the number of mature follicles (${\geq}14mm$) on triggering day per 100 IU of gonadotropin. A correlation between ovarian sensitivity and the baseline serum AMH level (absolute or multiples of the median [MoM] value for each corresponding age) was calculated. Correlation between ovarian response and serum AMH level was evaluated. Results: Ovarian sensitivity to mild stimulation was positively correlated with absolute serum AMH (r=0.535, p<0.001) or AMH-MoM value (r=0.390, p=0.003) in normoovulatory women, but this correlation was not observed in anovulatory women with PCOS (r=0.105, p>0.05, r=-0.265, p>0.05, respectively). Conclusion: Ovarian response to mild stimulation is possibly predicted by the serum AMH level in normoovulatory women, but not in anovulatory women with PCOS.

• The Korean Journal of Zoology
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• v.34 no.2
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• pp.253-256
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• 1991

Urothoe convexa, a new spedes of gammaddean amphipods from Korea, is described and illustrated. The present new species is similar in morphology to U. carda from Bay of Nhat- rang, Vietnam. But, the palm of gnathopod 2 of the present species is more convex than that of U. carda.