• Journal of Environmental Health Sciences
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• v.18 no.2
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• pp.117-124
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• 1992

Pretreatment with low concentration of Bleomycin and Cadmium rendered Chinese Hamster Ovary Cells more resistant to the induction of chromosome aberration by subsequent high concentration of same agent, however Mitomycin C did not function in that way. The cells pre-exposed to low dose of Cadmitim did not show cross-resistance to challenge dose of Mitomycin C for the induction of chromosome aberration, but cells pre-exposed to Bleomycin showed cross resistance. And the cells pre-exposed to low dose of Mitomycin C showed cross resistance to challenge of Bleomycin, but Cadmium did not.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.203-204
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• 2002

최근 양어사료는 어류양식의 발달과 함께 단순히 어류의 성장을 촉진시키기 위한 것으로부터 벗어나 영양원소 확충공급에 의한 사료효율 향상으로 사료비를 절감하고 양식어류의 품질을 좋게 하는 한편, 환경오염을 줄이고 면역성을 가져 질병에 대항할 수 있는 우수한 사료의 개발을 절실히 요구하고 있다. 현재 우리나라에서는 양어가들 나름대로 사료에 각종 첨가제를 첨가하여 사료의 질을 향상시키고 내병성을 추구하고 있으며, 학ㆍ연구계 역시 이러한 데에 초점을 맞추어 많은 연구를 하고 있다. (중략)

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.900-902
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• 1997

Stabilization of Power systems is investigated using a proportional-integral power system stabilizer(PI PSS). Time division PI PSS is examined in this paper. Two approaches are presented for determining the optimal stabilizer gains of the proposed PI PSS. Simulation results show that the proposed PI PSS yields better system dynamic performance and stability than the sub-optimal stabilizer in the sense of having greater damping in response to a step disturbance.

• Proceedings of the SAREK Conference
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• 2007.06a
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• pp.188-188
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• 2007

• Journal of Environmental Health Sciences
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• v.22 no.4
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• pp.77-81
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• 1996

The present experiment was carried out to examine the mechanism of cytotoxicity of Chromium in CHO cells. Chromium induced chromosomal aberrations in a dose-dependent manner. The most frequent type of aberration was chromatid deletions and chromosome type exchanges were also observed. Ultrafiltrates of culture media from CHO cells treated with Chromium induced sister chromatid exchanges(SCE) in CHO cells and Chromium induced lipid peroxidation. It was suggested that indirect effect through formation of clastogenic factor(CF) as well as direct effect on DNA might contribute to the cytotoxicity of Chromium.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.2
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• pp.130-136
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• 2000

Generally, the build-up printed circuit board manufactured by the sequential process with etching, plating, drilling etc. requires many types of equipments and lead time. Etching process is suitable for mass production, however, it is not adequate for manufacturing prototype in the developing stage. In this study, we introduce a screen printing technology to prototyping a build-up printed circuit board. As for the material, photo/thermal curable resin and conductive paste are used for the formation of dielectric and conductor. The build-up structure is made by subsequent processes such as the formation of liquid resin thin layer, the solidification by UV/IR light, and via filling with conductive paste. By use of photo curable resin, productivity is greatly enhanced compared with thermal curable resin. Finally, the basic concept and the possibility of build-up printed circuit board prototyping are proposed in comparison with to the conventional process.

• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.135-141
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• 2001

Endocrine disruptors have been implicated in carcinogenesis in animal studies, but carcinogenetic effects on human remain controversial. In order to examine the genotoxicity of two common endocrine disruptors, Bisphenol A and Diethylstilbestrol, cytogenetic endpoints including chromosome aberration (CA), sister chromatid exchange (SCE), micronuclei (MN) analyses and DNA damage by single cell gel electrophoresis (SCGE) were assessed. The effects of Bisphenol A and Diethylstilbestrol on the frequencies of CA and MN were increased in a dose-dependent manner and that of Bispheol A was more significant by Kendall'$\tau$test. Bisphenol A and Diethylstilbestrol also increased the frequency of SCE. Bisphenol A and Diethylstilbestrol induced DNA damage in a dose-dependent manner and the DNA damage induced by Diethylstilbestrol in human blood lymphocytes was more significant.

• Electronics and Telecommunications Trends
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• v.19 no.6 s.90
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• pp.83-92
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• 2004

정보통신 기술은 음성, 데이터, 영상, 멀티미디어 등 모든 형태의 정보를 디지털화가 가능하도록 발전하였고, 이를 기반으로 다양한 멀티미디어 서비스가 각종의 네트워크 및 단말기를 통하여 사용자에게 제공되고 있다. 그러나 현재에는 네트워크 및 단말기 특성에 맞추어 개별적인 콘텐츠를 각각 구축하여 제공하고 있기 때문에 시스템 구축 및 관리상에 부하가 많은 실정이다. 특히 컴퓨터, 통신, 방송 등 모든 정보통신 분야가 하나의 네트워크에 연결되는 광대역통합망 기반의 네트워크 사회로 빠르게 진화되는 상황에서 단일 콘텐츠로 네트워크 및 단말기 특성에 제역을 받지 않고 다양한 멀티미디어 서비스(multi-use)를 제공할 수 있는 멀티미디어 트랜스코딩 기술은 매우 중요하다. 본 고에서는 누구나 언제 어디서나 원하는 멀티미디어 서비스를 네트워크 및 단말기에 제약을 받지 않고 끊김없이 편리하게 이용할 수 있도록하기 위한 멀티미디어 트랜스코딩 기술 동향에 관하여 기술하고자 한다.

• Environmental Mutagens and Carcinogens
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• v.16 no.2
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• pp.117-123
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• 1996

This study was carried out to examine the mechanism of Arsenic cytotoxicity through several in vitro test systems. Dose-dependent decrease of cell survival by Arsenic was observed by colony forming assay. Arsenic was weak mutagenic in inducing HGPRT point mutation in CHO cells. The frequency of chromosomal aberrations increased in a dose-dependent manner and the most frequent type of chromosomal aberrations induced by Arsenic were chromatid type deletions. U!trafiltrates of culture media from CHO cells treated with Arsenic induced sister chromatid exchanges(SCE) in CHO cells and Arsenic was able to induce lipid peroxidation in CHO cells. The results suggested that the ultrafiltrates of media from CHO cells treated with Arsenic contain clastogenic factor(CF) and Iipid peroxidation might be involved in the formation of CF.

• Environmental Mutagens and Carcinogens
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• v.16 no.2
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• pp.88-96
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• 1996

Fluorescence in situ hybridization (FISH) with the DNA probe for human chromosome 4 was used to analyse in vitro radiation induced chromosome rearrangement in peripheral lymphocyte. Translocations, dicentrics, acentrics and color junctions involving the painted chromosome were scored according to the Protocol for Aberration Identification and Nomenclature Terminology (PAINT) system. The frequency of chromosome rearrangements including reciprocal translocation, dicentric, acentric fragment and color junction increased with radiation dose. The frequency of dicentric chromosome reduced by the fixation time following irradiation, whereas that of translocation was relatively persistent. The applicability of FISH for scoring stable translocation for biological dosimetry was demonstrated.