• Journal of the Korean Chemical Society
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• v.6 no.1
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• pp.14-18
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• 1962

Solution to the diffusion layer for the first order reaction at a droping mercury electrode (D.M.E.) is presented. Equations are derived for polarographic currents for the reactions at the D.M.E. A factor which is applicable to the D.M.E. is derived, when we use the equations of the polarographic currents for the reactions at a plane electrode(P.E.), and the rate constants of the backward reactions are negligibly small. Polarographic currents from a combination of diffusions and reactions are obtained at the D.M.E. with special approximation. Rate constant for the reaction of ferrous ion with hydrogen-peroxide is determined at the D.M.E.,using the data of Kolthoff and Perry. The agreement of the equation with the data of Kolthoff and Perry for the kinetic current of ferric ion in the presence of hydrogen-peroxide is good. Ratios of diffusion layer at the D.M.E. to the diffusion layer at the P.E. are discussed and show that, when the rate constants of the backward reactions for the first order reactions are larger than 1/0.05 sec-1. and drop-time about 3 sec., these ratioes are about one.

• The Journal of Society for e-Business Studies
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• v.14 no.3
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• pp.39-57
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• 2009

As electronic commerce becomes more common and the data volume of e-catalog increases, a systematic approach to data quality management is being required. Upon the necessity, we propose a process-based framework for e-catalog data quality management. This is the methodology for data management and improvement activities continuously performed to satisfy the expectation of industry to e-catalog systems. In the framework, contents for quality management consist of data, quality management items, and quality management processes. These are again subdivided according to organization levels, i.e, user, data administrator, and chief information officer.

• Korean Journal of Plant Taxonomy
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• v.37 no.2
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• pp.203-215
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• 2007

Uchiyama, Tomijiro visited the Korean peninsula including Busan, Incheon, Nampo, Pyongyang, Seoul, Mt. Geumgang of Gangwon-do, and Jeju-do twice for his plant collections in 1900 and 1902, respectively. During his plant explorations, Uchiyama collected numerous specimens which were investigated and studied by T. Nakai (Flora Koreana I and II and other publications) and H. $L{\acute{e}}veill{\acute{e}}$ later. Unfortunately all collection sites were simply described by Nakai in Romanized characters, so that it is difficult to pinpoint those sites using the current or the old Korean map. From this study, many locality names were reviewed based on his own plant specimens at TI and literatures, and those were listed as the order of his collection dates. Based on specimens deposited at TI, only ca. 200 specimens were confirmed, although 1,674 specimens were listed by Nakai. Among his collections, 2/3 of his collections were conducted in 1902 and among them 41 specimens were cited as type collections by Nakai.

• Journal of the Korean Ceramic Society
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• v.41 no.10 s.269
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• pp.723-727
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• 2004

Three kinds of $Si_3N_4$ powders (M-11, SN-ESP, and SN-E10) were gas-pressure sintered at $1700-1900^{\circ}C$ for 2 h under 18 atm $N_2$. Their densification behavior was investigated and compared as well as the mechanical properties and microstructure of the resulting ceramics. SN-ESP and SN-E10 started to reach nearly full densification at $1750^{\circ}C$ and showed almost no decomposition up to $1900^{\circ}C$. In contrast, M-11 was not fully densified until $1800^{\circ}C$ and showed about $3\%$ weigh loss at $1900^{\circ}C$ indicating poor thermal stability. SN-ESP and SN-E10 showed much higher strength both at room temperature and $1200^{\circ}C$ than M-11 when fully densified. Compared with SN-ESP, SN-E10 was not only a little better in strength (both at room temperature and $1200^{\circ}C$) and fracture toughness but also much higher in the Weibull modulus due to more interlocked microstructure by well elongated grains.

• Corrosion Science and Technology
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• v.17 no.6
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• pp.292-300
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• 2018

The modeling of 3D finite elements based on CAD data has been used to detect sites of corrosion defects in buried pipes. The results generated sophisticated profiles of electrolytic potential and vectors of current distributions on the earth surface. To identify the location of defects in buried pipes, the current distribution on the earth surface was projected to a plane of incidence that was identical to the pipe locations. The locations of minimum electrolytic potential value were found. The results show adequate match between the locations of real and expected defects based on modeling. In addition, the defect size can be calculated by integrating the current density curve. The results show that the defect sizes were $0.74m^2$ and $0.69m^2$, respectively. This technology may represent a breakthrough in the detection of indirect damage in various cases involving multiple defects in size and shape, complex/cross pipe systems, multiple anodes and stray current.

• The Journal of Korean Medicine
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• v.24 no.3
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• pp.65-71
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• 2003

목적 : 정천탕(定喘湯, JCT)이 IgE/mast cell로 유포되는 천식(喘息)등의 알러지성 질환에 대한 효과를 실험적으로 검증하고자 하였다. 방법 : IgE의 혈중농도와(in vivo) 분비 량을 측정하였으며(in vitro), 알러지 관련 유전자의 발현을 RT-PCR로 검색하였고, JCT의 수용성 복합 추출물이 compound 48/80로 유발되는 mast cell line(IC-2)의 histamine의 방출에 미치는 직접적인 영향을 측정하였다(in vitro). 결과 : 정천탕은 ovalbumin으로 유발시킨 마우스의 혈중 IgE량과 IL-4와 CD-40로 유도시킨 spleen B 임파구의 IgE 생성량도 현저하게 감소시켰다. 또한 INF-r의 발현은 증가시킨 반면, IL-4와 IL-6의 발현과 mast cell의 histamine 방출은 억제하는 것으로 나타났다. 결론 : 정천탕의 항알러지 효과를 실험적으로 확인 할 수 있었으며 임상적으로는 천식등 알러지성 질환에 사용 할 수 있을 것으로 사료된다.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1987.10a
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• pp.255-257
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• 1987

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.219.3-220
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• 2000

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.177.1-177
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• 2003

No Abstract, See Full Text

• IMMUNE NETWORK
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• v.23 no.1
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• pp.1.1-1.3
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• 2023