• 한국해양학회지
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• v.29 no.4
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• pp.338-356
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• 1994

Sediment samples from the continental shelf of the South Sea of Korea are analysed to determine the concentration of Al, Fe, Mn, cu, Ni, Zn, Co, Cr and Pb. among these samples, fine-grained sediments were also analysed by a sequential extraction technique to know geochemical forms of the metals in this environments. The total concentration of Al, Fe, Cr, Ni, Cu and Zn in bulk sediments decreased gradually with the increase of distance from the coastal zone. This distribution patterns are well coincide with grain size distribution. However, the patterns of Mn, co and Pb do not follow such and overall distribution. The concentration of Pb, particularly, did not show any features in areal distribution, which may be result from different pathways to the sediments, compared to the other metals. the speculation data show that a considerable amount of Cd, Mn and Co are bounded in the carbonate fraction, accounting for 42.8%, 40.3% and 30.6%, respectively. Cu, Zn, Mn and Fe are largely associated to oxide fraction with proportions of 34.4%, 23.1%, 15.5% and 13.7%, respectively. However, the metals in residual fraction account for more than 50% of the total metal concentration, except for Mn. These observations emphasize that residual fraction in the dominant component controlling the elemental concentration.quartz and glauconite grains.Accordingly,these sediments are interpreted as an extension part of transgressive sand deposit that are widely distributed on the continental shalf floor of southern Yellow Sea.

• Korean Journal of Microbiology
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• v.46 no.4
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• pp.313-318
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• 2010

Deinococcus radiodurans RecA protein, when bound to DNA, exhibits a DNA-dependent ATPase. In the absence of DNA, the rate of RecA protein-promoted ATP hydrolysis drops 1,000-fold under the physiological concentrations of salt. This DNA-independent activity can be stimulated to levels approximating those observed with DNA by adding high concentrations (approximately 1.6 M) of a wide variety of salts. This effect was characterized by varying salt concentration and comparing the effects of different ion types. The higher concentrations of salt stimulated the ATP hydrolysis by RecA protein in the absence of DNA. At 1.6 M chloride, the observed stimulation showed the following cation trend $K^+{\geq}Na^+$ > $NH_4^+$ and the following anion sequence was observed: $glutamate^- \; > \; C1^- \;> \; acetate^-\; > \;PO_4^-$ at 1.6 M $K^+$. The catalytic properties of the salt-stimulated ATP hydrolysis reaction was optimal between pH 7.0 and 8.0, which was similar to the double stran nded DNA-dependent ATPase activities of Deinococcus radiodurans RecA protein. In the absence of DNA the active species for ATP hydrolysis by RecA protein was shown to be an aggregate of three RecA protein molecules.

• Cement Symposium
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• s.37
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• pp.59-67
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• 2010

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2007.05a
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• pp.324-325
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• 2007

• The Korean Publising Journal, Monthly
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• s.205
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• pp.4-4
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• 1997

최근 학계 동향을 토대로 새해에 주문하고 싶은 것은 생태학적 관점에서의 접근이 역사시대쪽으로 확산되었으면 하는 점이다. 또 지역사회의 존재형태에 대한 밀도 높은 연구, 식민지 근대화 문제의 심층적 연구, 해방 이후 현대사에 대한 반성 등이 책으로 결실을 맺기 바란다.

• Proceedings of the KSEEG Conference
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• 2001.04a
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• pp.12-15
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• 2001

• KOREAN POULTRY JOURNAL
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• v.24 no.6 s.272
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• pp.131-135
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• 1992

칼슘과 인은 동물체내에 존재하는 광물질로 칼슘이 대략 $1.6{\~}2.0{\%}$, 인이$0.9{\~}1.1{\%}$ 함유되어 있다. 칼슘과 인은 주로 뼈에 많이 함유되어 있는데 주로 $Ca_3(PO_4)_2$의 형태로 존재한다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.1
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• pp.25-32
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• 1999

In order to examine the degree of heavy metal pollutions around Samcheonpo and Youngkwang power plants, marine sediment samples were analyzed to determine heavy metal contents. Some of these sediment samples were also analyzed by using of a sequential extraction technique to know geochemical forms of the metals. The results showed that the spatial distribution of heavy metals coincided very well with those of mean grain size, carbonates and organic matters. The chemical speciation data using sequential extraction analysis also showed that a considerable amount of heavy metals except for Mn were bounded in the residual fraction, which mode of occurrence of heavy metals was generally interpreted as being the result of the lithogenic origin.

• Transactions of the Korean Society of Mechanical Engineers
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• v.7 no.4
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• pp.483-488
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• 1983

비교적 저온의 순수물 속에 있는 수직얼음 원기둥 주위에서 일어나는 자연대류 현상을 수치계산 방법을 사용하여 이론적인 해를 추구하였으며 기존 실험결과와 비교하였다. 유동의 형태는 주위 유체의 온도에 따라서 상향유동, 하향유동, 이 양자가 동시에 존재하는 유동의 형태로 구분되었으 며 해를 구할 수 있는 영역내에서는 상향유동과 하향유동이 동시에 존재하는 구역에서 열전달율 이 최소가 됨을 알 수가 있었다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.8 no.3
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• pp.274-287
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• 1984

밀폐용기 내의 자연대류에 의한 흐름현상에 고유하며 아직까지 해결되지 않고 있는 중요한 문제 는 그 내부흐름의 형태를 주어진 물리적인 조건으로부터 미리 예측할 수 없다는 것이다. 이는 이 문제의 해석적인 해결에 가장 큰 난점이 되고 있다. 본 논문에서는 multiple scales method를 이 용한 해석적인 모델을 개발하여 종횡비가 낮은 직각형 밀폐용기 내에서 운동력이 코어에 존재하 는 경우 그 내부 흐름형태를 scaling analysis를 통해 정성적으로 예측, 기존의 결과와 비교 검토 하였다.