• Corrosion Science and Technology
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• 제5권5호
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• pp.160-167
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• 2006

S-Acetyl Isothiourea Acetate (S-AITA) was synthesized in the laboratory and this influence on the inhibition of corrosion of mild steel in 1.11 N hydrochloric and 1.12 N sulphuric acids was investigated by weight loss and potentiostatic polarization techniques at 303K, 353K and 403K. These results were confirmed by the impedance technique. The inhibition efficiency increased with increase in concentration of inhibitor and decreased with rise in temperature from 303K to 403K. The maximum inhibition efficiency of S-AITA was found to be 99.95% (0.5% of S-AITA) at 303K in sulphuric acid. The adsorption of this compound on the mild steel surface from the acids has been found to obey Temkin's adsorption isotherm. The potentiostatic polarization results revealed that S-AITA was a mixed type inhibitor. Some thermodynamic parameters i.e., activation energy (Ea), free energy of adsorption (${\Delta}G_{ads}$), enthalpy of adsorption (${\Delta}H$) and entropy of adsorption (${\Delta}S$) were also calculated from weight loss data.

• 천문학논총
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• 제25권4호
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• pp.167-176
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• 2010

In the region of the intermediate open cluster M35 (NGC 2168), the time-series of V CCD images was taken for 12 nights from December 18, 2007 to September 25, 2010. From this observation, we detected 22 variable stars including 15 new ones. They are 6 $\delta$ Scuti, a Cepheid, an RR Lyrae, 9 eclipsing binaries and 5 semi-long periodic and/or slow irregular type variable stars. For the V photometry of the $\delta$2 Scuti stars, the multi-frequency analysis was performed using the Discrete Fourier Transform and the linear least-square fitting.

• Kyungpook Mathematical Journal
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• 제45권4호
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• pp.481-489
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• 2005

We first show that any complete MV-algebra whose Boolean subalgebra of idempotent elements is atomic, called a complete MV-algebra with atomic center, is isomorphic to a product of unit interval MV-algebra 1's and finite linearly ordered MV-algebras of A(m)-type $(m{\in}{\mathbb{Z}}^+)$. Secondly, for a semi-simple MV-algebra A, we introduce a completion ${\delta}(A)$ of A which is a complete, MV-algebra with atomic center. Under their intrinsic topologies $(see\;{\S}3)$ A is densely embedded into ${\delta}(A)$. Moreover, ${\delta}(A)$ has the extension universal property so that complete MV-algebras with atomic centers are epireflective in semi-simple MV-algebras

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2005년도 한국우주과학회보 제14권1호
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• pp.33-33
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• 2005

• Journal of the Korean Data and Information Science Society
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• 제28권3호
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• pp.493-504
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• 2017

통계청 인구총조사의 출생아 수 자료는 우리가 쉽게 접할 수 있는 가산 자료이며 국가경쟁력 제고를 위한 정부의 출산정책 결정 및 그 기대효과 분석의 기반이 되는 자료이다. 출생아 수 자료 분석에 있어서 포아송 모형 등 가산 모형이 우월하다는 선행 연구결과에 의하여 가산 모형을 통한 자료 분석방법이 활용되고 있다. 이 때 가산 모형에서 가장 많이 사용하는 포아송 모형은 균등상포라는 제한적인 가정을 토대로 하기 때문에 출생아 수 자료 분석에 이 포아송 모형을 그대로 적용한다면 정보의 손실과 편향추정을 피할 수 없게 된다. 이러한 한계를 극복하기 위해 Ghosh 와 Kim (2007)은 영 과잉과 부족으로 인한 과대산포와 과소산포를 동시에 설명할 수 있는 영 변환 모형 (zero-altered model)을 제안하였다. 본 논문에서는 Ghosh 와 Kim (2007)의 영 변환 모형을 적용하여 실제 출생아수분포에서 영 변환 모형의 산포형태모수 ${\delta}$를 도출하고 그 역할에 대하여 분석한다. 그리고 관측분포에서의 산포형태모수 ${\delta}$와 이론적분포와의 차이를 비교하기 위한 적합도 검정통계량과의 유사성을 확인한다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.144.1-144
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• 2003

Attenuated viruses can protect their hosts against challenge to their related viruses. Increasing evidence shows that mutations of the tobamoviral 126/183 kDa protein play a major role in the viral attenuation and contribute to the cross protection mechanism. In this study, four mutants of Pepper mild mottle virus (PMMoV) have been constructed by mutagenesis; two mutants, pTPpoly348 and pTPpoly762, were substituted in the middle of replicase gene, and the others, pTPL3D:: $\Delta$6207 and pTPL3D:: $\Delta$6219, were deletion mutants made by deleting some parts of pseudoknot structures of the 3' noncoding region (NCR) of the virus. Progeny viruses generated from the four mutants were infectious on N. benthamiana plants with symptomless or mild mosaic symptom. Replication efficiency and viral product accumulations of four mutants were assessed by Northern and Western blot analyses on BY-2 protoplast cells. Accumulation of CP for the pTPL3D:: $\Delta$6207 and pTPL3D:: $\Delta$6219 were lower than that of other mutants and wild type virus. These data suggest that the 3'-NCR mutations contribute to the viral gene expression in host tissues, while mutants of replicase gene rather govern the symptom expression.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2014년도 추계학술대회 및 정기총회
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• pp.43-43
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• 2014

The rice blast disease caused by of Magnaporthe oryzae is one of the most destructive diseases of rice. By the microarray analysis, we profiled expression changes of genes during conidiation and found out many putative genes that are up-regulated. Among those, we first selected MGG_06399 encoding a dual-specificity tyrosine-regulated protein kinase (DYRK), homologous to YAK1 in yeast. To investigate functional roles of MoYAK1, We made ${\Delta}Moyak1$ mutants by homology dependent gene replacement. The deletion mutant showed a remarkable reduction in conidiation and produced abnormally shaped conidia smaller than those of wild type. The conidia form ${\Delta}Moyak1$ were able to develop a germ tube, but failed to form apppressoria on a hydrophobic coverslip. The ${\Delta}Moyak1$ formed appressria on a hydrophobic cover slip when exogenous cAMP was induced, but the appressoria shape was abnormal. The ${\Delta}Moyak1$ also formed appressoria abberent in shape on onion epidermis and rice sheaths and failed to penetrate the surface of the plants. These data indicate that MoYAK1 is associated with cAMP/PKA pathway and important for conidiation, appressorial formation and pathogenic development in Magnaporthe oryzae. Detailed characterization of MoYAK1 will be presented.

• Journal of Microbiology and Biotechnology
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• 제9권5호
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• pp.679-682
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• 1999

When the human parathyroid hormone (hPTH) is expressed as a secretory product in S. cerevisiae, most of the secreted hPTH is internally cleaved by endoproteolytic processing. To investigate whether the yeast endoproteases such as Kex2p, Yap3p, and Mkc7p are involved in the endoproteolytic processing of hPTH in S. cerevisiae, hPTH was expressed in S. cerevisiae mutants deficient in one or two of the following well-known endoproteases such as Kex2p, Mkc7p, and Yap3p. Among these mutants, the yap3-disrupted(yap3$\Delta$) and yap3/mkc7-disrupted (yap3Δmkc7$\Delta$) yeasts showed a significant reduction in the extent of hPTH proteolysis. In contrast, the mkc7-disrupted (mkc7$\Delta$) yeast did not reduce the proteolysis of hPTH as compared to the wild type. This suggests that Mkc7p is not involved in the endoproteolytic processing of hPTH. It was also found that the kex2-disrupted (kex2$\Delta$) mutant was not able to secrete a detectable amount of hPTH.

• 전력전자학회논문지
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• 제4권3호
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• pp.231-239
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• 1999

변압기로써 결합된 직렬공진 부하를 가진 전압원-인버터(Voltage-Source Inverter)가 공진주파수로 작동되는 경우에 출력 전류를 제어하는 기법으로서, 개선된 전류조절형 델타변조(Current-Regulated Delta Modulator; CRDM)방식을 제안한다. 일반적인 CRDM은, 전류편차가 상당한 크기로 나타난다는 문제가 있으며, 특히 유도가열장치와 같이 부하가 변압기를 통하여 연결되는 경우에는 변압기의 자속포화 문제가 발생하므로 실제 사용에 한계가 있다. 이러한 문제를 해결하기 위하여, 자속포화 현상을 분석하고 이를 방지하기 위한 간단한 방법을 제안하며, 전류편차를 제거하기 위한 적분형 CRDM을 적용한다. 그리고 슬라이딩 모드 제어의 개념을 이용하여, 안정된 동작을 보장하는 적분기 이득의 상한치를 회로특성치로부터 구하는 방법을 제안하고, 제안된 기법의 효용성을 시뮬레이션과 실험으로써 확인한다.

• 약학회지
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• 제21권3호
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• pp.167-171
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• 1977

A new assay method for delta-l-dehydrogenated-3-ketoco-rticosteroid in the presence of proteinous material or whole-cell-enzyme and 3-ketocorticosteroid has been developed. This method makes use of the linear relationship between the ratio of absorbances at 265 nm and at 242 nm and the fractional concentration of delta-1-3-ketosteroid. Theoretical values were calculated based on the absorbances of proteinous material at fixed concentrations of the 3-ketosteroid and delta-1-dehydrogenated-3-ketosteroid. The values obtained experimentally showed good agreement with the values obtained experimentally showed good agreement with the values theoretically predicted. The new assay method developed for the steroid mixtiure containing proteinous material is of some practical importance. The use of such assay method enables one to determine the enzyme activity and the rate of enzyme reaction or conversion rather quickly, easily and accurately. By the use of this assay method, the reaction kinetics of whole-cell-enzyme has also been studied. It was found that it followed the simple Michaelis-Menten type enzyme kinetics. Also the reversibility of this reaction with actively metabolizing cell was examined. It was found that delta-l-dehydrogenated-3-ketosteroid could not be hydrogenated reversibly to 3-ketosteroid by this enzyme system.