• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.05a
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• pp.75-75
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• 2003

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.75-75
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• 2003

Silica has been known to be a factor in acute cell injury and chronic pulmonary fibrosis. In Rat2 fibroblasts, silica induced the activation of NFkB, which plays a crucial role in regulating the expression of many genes involved in the subsequent inflammatory response. In addition, we observed that TAK1 and NIK were involved in silica-mediated NF-kB activation in Rat2 cells. (omitted)

• 한국약용작물학회:학술대회논문집
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• 2012.05a
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• pp.231-232
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• 2012

• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1906-1908
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• 2013

• Journal of the Korean Society of Costume
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• v.8
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• pp.15-27
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• 1984

A costume study is a part of the cultural history and also has the greatest relation to life's senses as a concrete culture. Korean costume that consists a double structure with Chinese one through Chosun Dynasty five hundred years, has recently changed up to the Western Form. In this respect Korean Costume has a important meaning in relation to Western costume. Traditional costume, generally speaking, has tendency to keep up by the common people than the higher classes. Then there were four classes. They are aristocratic classes common people, those who are engaged in the form, industry, trade and low classes. Merchant of them partially took charge of the cultural exchange about contacting with tradition and new one. Because it's easy to flow in one's character the new civilization. So there is an important significance to research of the merchant's costume in Gae Hwa Gi changing age of civilization in politics, economic, and social system. The records appeared about the merchant's costume in the age of civilization through literature study and natural photo at that time.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.2
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• pp.217-224
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• 2009

This paper presents a new AC/DC converter scheme for HVDC system to achieve a high power factor operation. The new AC/DC converter consists of two 12-pulse bridge converters in series: the primary and auxiliary converters. Ignition angles of the main and auxiliary converters are controlled independently to maintain the nominal DC voltage and control auxiliary voltage. The resulted DC voltage obtained by superimposing the above two phase modulated voltages can be controlled very rapidly over a wide range, and a high power factor operation is achieved. Performance improvements in power factor and harmonic distortion are validated by theoretic derivations and experiments with prototype HVDC system. With the proposed converters, investment for reactive power compensation and filter in HVDC system can be saved significantly.

• Journal of Korean Society on Water Environment
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• v.24 no.5
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• pp.592-597
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• 2008

Current water quality standard (WQS) in Korea is based on the protection of human health, not considering the protection of aquatic organisms. Most of chemicals can be toxic to ecological biota as well as human. Health of aquatic biota is closely related to the human health via food chain, therefore ecological risk based-WQS needs to be developed to protect the aquatic ecosystem. In this study, we selected the 31 chemicals in the Project entitled 'Development of integrated methodology for evaluation of water environment'. The methodology for calculating water quality criteria was derived from the Australian and New Zealand processes for deriving guideline trigger value for aquatic ecosystem. The available ecotoxicity data were collected from US EPA's ECOTOXicology Database (ECOTOX), TOX-2000 Database, European Chemicals Bureau (ECB)'s International Uniform Chemical Information Database (IUCLID) and Environmental Protection Agency (US EPA)'s report 'Ambient Water Quality Criteria (AWQC)'. The aquatic toxicity data for the Korean species were selected for risk assessment to reflect the Korean water environment. The monitoring values were calculated from the water quality monitoring data four main Korean rivers. We suggested the order of priorities of chemicals based on ecological risk assessment. We expect that these results can be useful information for establishing the WQS for the protection of aquatic ecosystem.

• Korean journal of applied entomology
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• v.16 no.1 s.30
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• pp.1-6
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• 1977

The 'Kresek' disease in Korea caused by Xanthomonas oryzae was first found from eight counties in Jeon-nam and Kyungnam province in 1976. The study has been carried mainly on the grouping of pathogens and reproduction of the symptoms on Milyang #23, the variety had shown severe damages at the fields, by using the isolates from Hwa-sun and Kwang-san counties where the first epidemics took place. 1. The 'Kresek' disease was found mainly on Milyang #23, a new variety, at Hwa-sun, Mu-an, Kang-jin. Yung-am, Gog-sung counties in Jeon-nam province and Jin-yang county in Kyung-nam province. 2. The groups of 'Kresek' causing pathogens were the same of those producing bacterial leaf blight symptoms such as group I , II, IN and V of Xanthomonas oryzae. 3. Seventeen out of 21 isolates from Hwa-sun county where the first and severe damage found belonged to group IV, 2 to group II and 2 to group V All of 5 isolates from Kwang-san county belonged to the group IN. 4. The 'Kresek' type symptom could reproduced within 5 days after inoculation to seedlings by using root tut, spray and needle inoculation methods. j. The most of effective method for the inoculation was root cut, and then were spray and needle method. respectively. The higher concentration of inoculum produced the higher disease incidence.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.39 no.5
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• pp.43-50
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• 2002

To improve the current waveform of diode rectifiers, we propose a new operating principle for the voltage -doubler diode rectifiers. In the conventional voltage-doubler rectifier circuit, relatively large capacitors are used to boost the output voltage, while the proposed circuit uses smaller ones and a small reactor not to boost the output voltage but improve the input current waveform. A high input power factor of 97[%] and an efficiency of 98[%] are also obtained. The harmonic guide lines of proposed rectifier is no interfered with inverter switching, resulting in a simple, reliable and low-cost ac-to dc converters in comparison with the boost-type current-improving circuits.It compared conventional pulse-widthmodulated(PWM)inverter with half pulse-widthmodulated (HPWM) inverter. Proposed HPWM inverter eliminated dead-time by lowering switchingloss and holding over-shooting.

• Journal of the Korean Data and Information Science Society
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• v.19 no.3
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• pp.723-734
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• 2008

The main reason for deinterlacing is frame-rate conversion. The other reason for deinterlacing is of course improve clarity and reduce flicker. Using a deinterlacer can help clarity and stability of the image. Many deinterlacing algorithms are available in image processing literatures such as ELA and E-ELA. This paper propose a new statistical deinterlacing algorithm based on statistical tests such as the Bartlett test, the Levene test and the Kruskal-Wallis test. The results obtained from the proposed algorithms are found to be comparable to those from many well-known deinterlacers. However, the results in the proposed deinterlacers are found to be more efficient than other deinterlacers.