• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.148-152
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• 2006

본 연구에서는 공단지역 내 토양층(지표면하 1 m 이내)에 존재하는 Cu, Pb 성분의 평균값보다 높은 지역과 중앙값보다 높은 지역을 확률적으로 추정하고자 하였다. 먼저, 연구지역의 Cu, Pb 성분의 농도 분포를 파악하기 위해 일반통계분석을 하였고, 공단지역 내 Cu, Pb 성분의 평균값과 중앙값을 제한값으로 하여 지시크리깅을 수행하여 평균값보다 높은 확률도와 중앙값보다 높은 확률도를 작성하였다 평균값과 중앙값에 의해 작성된 확률도를 비교하여, 지시크리깅의 제한값으로서의 적합성을 분석하였다.

• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.38-38
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• 2015

Throughout the world, clubroot disease is one of the most damaging diseases affecting Brassica oleracea. In order to perform QTL analysis of CR (clubroot resistance) loci in B. oleracea, we constructed a map, and analyzed CR-QTLs using the mean phenotypes of F3 progenies from the cross of a resistant double-haploid cabbage line (Anju) with a susceptible double-haploid broccoli line (GC). We identified one major QTL, pb-Bo(Anju)1 in C2 from Anju and four minor QTLs; pb-Bo(GC)1 in O5 from GC, pb-Bo(Anju)2, -3, -4 in C2, C3, and C7 from Anju, respectively. Additionally, we found that the accumulation of Pb-Bo(Anju)1 allele and the minor CR-QTLs is essential for resistance against various six isolates. Our finding markers closely linked to the CR-QTLs will help marker-assisted selection for CR. At present, we are undergoing toward map-based cloning for Pb-Bo(Anju)1 gene. The preliminary experiment delimited Pb-Bo(Anju)1 locus, encompassing among 450kB.

• Corrosion Science and Technology
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• v.17 no.3
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• pp.116-122
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• 2018

The secondary coolant of a nuclear power plant has small amounts of various impurities (S, Pb, and Cl, etc.) introduced during the initial construction, maintenance, and normal operation. While the concentration of impurities in the feed water is very low, the flow of the cooling water is restricted, so impurities can accumulate on the Top of Tubesheet (TTS). This environment is chemically very complicated and has a very wide range of pH from acidic to alkaline. In this study, the characteristics of the oxide and the mechanism of stress corrosion cracking (SCC) are investigated for Alloy 690 TT in alkaline solution containing Pb, Cl, and S. Reverse U-bend (RUB) specimens were used to evaluate the SCC resistance. The test solution comprises 3m NaCl + 500ppm Pb + 0.31m $Na_2SO_4$ + 0.45m NaOH. Experimental results show that Alloy 690 TT of the crevice environment containing Pb, S, and Cl has significant cracks, indicating that Alloy 690 is vulnerable to stress corrosion cracking under this environment.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.6
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• pp.727-738
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• 1999

Total 76 aerosol samples were collected at Sungsan in Cheju Inland by high volume air sample for 1 year, from May 1995 to April 1996, and were analyzed for major elements(Na, Mg, Ca, Al, Fe) and trace elements(Mn, Co, Ni, Zn, Cd, Pb, U) by ICP/AES and ICP/MS. This study aims to determine the concentrations of trace metals and their seasonal variations in the atmosphere of Cheju Island, where is the remote area from pollution sources and also is the midway of transport of Asian continental materials into the western North Pacific. The concentrations of Na and Mg contributed by sea-salt aerosols were similar to those in the western part of Cheju island(Kosan) and in the western coast of Korea(Mallipo). They showed the highest value in summer and the lowest in spring and winter. Crustal metals(Al, Fe, Ca, Mn, Co, U) were 2~3 times lower than those of Mallipo. These metals showed the lowest values in summer and the highest in spring. Pollution-derived metals (Zn, Cd and Pb) were 2~4 times lower than those in Malipo. Some elemental ratios in aerosols grouped by three wind directions(north-northwest, east, and south-southwest) such as Fe/Al and Pb/Zn are presented as useful tracers indicating source areas, and their differentiation may be explained by geology and fuel types of source areas.

• Journal of the Korean earth science society
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• v.44 no.1
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• pp.36-46
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• 2023

In this study, small bird tracks from the Cretaceous Sanbukdong Formation in Gunsan City, South Korea, were briefly described. Detrital zircon SHRIMP U-Pb dating was conducted of the tuffaceous sandstone from the formation to determine the depositional age of the vertebrate track-bearing strata. Small bird tracks are not well-preserved but divided into two types: two consecutive tracks and three isolated tracks. They are small, asymmetric, slender, functionally-tridactyl tracks, which lack a web between digits. The consecutive and isolated tracks were identified as Koreanaornis dodsoni? and Koreanaornis ichnosp., respectively. This study adds avian tracks to the Sanbukdong tetrapod track assemblage composed of theropods, ornithopods, and pterosaur tracks. According to the U-Pb dating, the estimated age of the Sanbukdong Formation is 112.5±5.8 Ma, regard as the Aptian Stage, representing the maximum depositional age for the Sanbukdong Formation. The Sanbukdong Formation can be correlated with the lower part of the Jinju Formation in the Gyeongsang Basin. Thus, small avian tracks may represent the oldest Korean occurrence of Koreanaornis.

• Proceedings of the Korean Ceranic Society Conference
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• 2000.10a
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• pp.146.2-146
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• 2000

• Proceedings of the Korean Ceranic Society Conference
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• 2000.10a
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• pp.70.1-70
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• 2000

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2011.05a
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• pp.121-122
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• 2011

원자력 발전소 등 산업체 설비의 부식을 모니터링하고 부식 생성여부와 지속적인 사용 가능성을 판단하며, 그 상황에서의 적절한 조치을 취하게 할 수 있는 전기화학적 노이즈 측정은 정밀제어기술의 발전과 함께 그 응용 가능성이 커짐에 따라 관심이 증대되고 있기에 이를 본 연구에 적용 하고자 한다.

• International Journal of Automotive Technology
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• v.7 no.3
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• pp.337-343
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• 2006

Numerical calculations are made in order to find a possible correlation between the J-integral and the crack mouth opening displacement(CMOD) in dynamic nonlinear fracture experiments of 3-point bend(3PB) specimens. Both elastic-plastic and elastic-viscoplastic materials are considered at different impact velocities. The J-integral may be estimated from the crack mouth opening displacement which can be measured directly from photographs taken during dynamic experiments.

• Proceedings of the KWS Conference
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• 2007.11a
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• pp.218-221
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• 2007

The surface mounting technology of 0402 electric chip part is necessary to fabricate a high density and multi-functional module, but there is a limitation of the technology, like as a bridge and self-alignement. This work estimated SMT processing factors of 0402 chip. To obtain optimum SMT process, we evaluated effects of stencil thickness, shape of hole on printability and mountability. Printability shows best results under the thickness of $80{mu}m$ with circle hole shape and 90% square hole shape. In case of chip mounting process, chip mis-alignment and bridge was occurred rarely in same conditions. In more thin stencil thickness, $50{mu}m$, strength of 1005 chip parts was poor, because of amount of printed solder was insufficient.