• Title/Summary/Keyword: 90s

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Studies on the Sorption Characteristics of $^{90}Sr$ onto Granite and Tuff

  • Cho, Young-Hwan;Park, Chung-Kyun;Hahn, Pil-Soo
    • Nuclear Engineering and Technology
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    • v.29 no.5
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    • pp.393-398
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    • 1997
  • Batch sorption experiments were carried out to investigate the sorption characteristics of $^{90}$ Sr onto domestic granite(HG) and tuff(TF) samples. The effect of three independent variables ([Sr], Vo1/Wt], [pH]) on the sorption was investigated. (Sr) played as the most significant variable for the $^{90}$ S $r^{2+}$ sorption onto HG, whereas [pH] had the greatest effect among three variables onto TF. Tuff shooed much greater sorption than granite, which ues accounted for their differences in mineralogical properties. The selectivity of $^{90}$ Sr was much lower than that of $^{l37}$Cs.s.s.

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A Performance Analysis of a Spark Ignition Engine Using Gasoline, Methanol and M90 by the Thermodynamic Second Law (가솔린, 메탄올, M90 연료를 사용한 전기점화기관에서의 열역학 제 2법칙적 성능해석)

  • Kim, S.S.
    • Journal of Power System Engineering
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    • v.13 no.6
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    • pp.22-28
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    • 2009
  • 열역학 제 2법칙의 관점의 열역학적 가용에너지인 엑서지 해석법을 적용하여 가솔린, 메탄올, M90 연료를 사용한 전기점화 기관의 성능해석을 수행하였다. 열역학적 사이클 해석을 위하여 사이클을 구성하는 각 과정은 열역학적 모델로 단순화하였고, 크랭크 각도에 따른 실린더의 압력과 작동유체를 구성하는 연료, 공기 및 연소생성물의 열역학적 물성 값들을 이용하여 각 과정에서의 엑서지와 손실 일을 계산하였다. 실험데이터는 단기통 전기점화기관을 가솔린, 메탄올과 M90(메탄을 90%+부탄 10%의 혼합연료)을 연료로 WOT(Wide Open Throttle), MBT(Minimum advanced spark timing for Best Torque), 2500rpm 조건으로 운전하여 측정하였다. 계산에 이용한 자료는 실험으로 측정한 크랭크 각도에 따른 연소실의 압력, 흡입공기와 연료유량, 흡입공기 온도, 냉각수 온도와 배출가스 온도 등이다. 이를 이용하여 각 과정에서의 엑서지와 손실 일을 계산하였으며 각 과정에서의 손실 일은 연소과정에서 가장 크며 팽창과정, 배출과정, 압축과정 및 흡입과정 순으로 크게 나타났다.

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A Study on the Stress Wave Propagation of Composite Laminate Subjected to Low-Velocity Impact (저속 충격을 받는 적층 복합재의 응력파 전파에 관한 연구)

  • 안국찬;김문생;김규남
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.13 no.1
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    • pp.9-19
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    • 1989
  • The impact stress and wave propagation of graphite/epoxy and glass/epoxy laminates subjected to the transverse low-velocity impact of steel balls are investigated theoretically. A plate finite element model based on Whitney and Pagano's theory for the analysis of heterogeneous and anisotropic plates taking into account of the transverse shear deformation is used for the theoretical investigation. This model is in conjuction with static contact laws. The basic element is a four-node quadrilateral with the five degrees-of-freedom per node. The reduced integration technique is used for shear locking associated with low-order function in application to thin plates. These two materials are composed of [0.deg./45.deg./0.deg./-45.deg./0.deg.]$_{2S}$ and [90.deg./45.deg./90.deg./-45.deg./90.deg.]$_{2S}$ stacking sequences and have clamped-clamped boundary conditions. Finally, the present results are compared with an existing solution and wave propagation theory and then impact stress and wave propagation phenomena are investigated.gated.

Study on the Characteristics of Noise/Vibration in the Upright Laying Hen House (직립식 산란계사 내의 소음 진동 발생 현황 조사연구)

  • Lee S.J.;Chang D.I.;Chang H.H.
    • Journal of Animal Environmental Science
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    • v.12 no.1
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    • pp.21-28
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    • 2006
  • This study was carried out to measure and analyze the characteristics of noise and vibration, and to analyze their effects on the productivity of layers, mechanical troubles, and abnormal wear-out failure of facilities and equipment of the layer house. The measurements of noise and vibration were taken at 13 layer farms nationwide for the operations of feed supplier system, feed distribution system, automatic egg collection system, ventilation system, blot conveyer for layer feces, and fur the case of with and without their operation by a sound level meter and a vibration measuring system in the layer house equipped with upright multi-tier cages. Measurement results showed that normal times were noise(N) 82 dB and vibration(V) 0.2072 cm/s, feed supplier system were 90 dB(N) and 2.8560 cm/s(V), feed distribution system were 90 dB(N) and 2.0222 cm/s(V), automatic egg collection system were 87 dB(N) and 0.1865 cm/s(V), ventilation system 88 dB(N) and 2.5364 cm/s(V), belt conveyer fur layer feces were 88 dB(N) and 0.2387 cm/s(V), and then maximum values of noise and vibration were 90 dB and 2.8560 cm/s, respectively, when feeding systems(feed supplying system and feed distribution system) were operated. Based on these results, an experiment is being conducted to find out the effect of noise and vibration on the productivity of layers in the layer house equipped with upright multi-tier cages.

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study on the Transfeal Phenomenon of Anti-fashion into Mother-fashion -In the Case of Hippie Look- (저항패션이 모패션으로 전이된 현상에 관한 연구 -히피풍을 중심으로-)

  • 박명희
    • Journal of the Korean Society of Costume
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    • v.28
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    • pp.239-253
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    • 1996
  • The purpose of this dissertation is to exam-ine the hippie look which is one of the most popular fashion trends in the early 90s, in re-lation to the hippie style in 60s and cultural restoration. in order to investigate the re-lationship this dissertation studies the trans-feral phenomenon of anti-fashion into mother fashion in the basis of social and clutural theories. hippie culture is the anti-culture which appeared in America in the late 60s, it tried to create a new culture by subverting the ruling class culture with their combative life style and peculiar appearance which are distinguished from mother culture. First of all to examine the inner symbolic meaning and outer shape of the hippie style I divided the characteristics of the hippies into ideology social value and attitude on sex. in the aspect of ideology the hippie show strong subjectivity while mother culture shows ob-jectivity. in social value the hippie has the resisting chaacteristics while mother culture has the conformative characteristics. In the aspect of sex the hippie tries to break the fixed idea of mother culture. Hippie culture as anti-culture is symbolically expressed in hippie style fashion which is dif-ferent from mother fashion in shape. There-fore the inner meaning and the outer shape of the hippie style shows strong characteristics of anti-fashion. Hippie style as anti-fashion has an effect on high fashion in the late 60s and the early 70s and on hippie look which is restored in 90s. however hippie-look in 90s is a mother-fashion in which all symbolic mean-ings of the hippie style are weakened and the only outer shape of hippie style is presented and suggested. It doesn't show any cultural backgrounds ideology social value and new attitude on sex of the hippies. The transferal phenomenon of anti-fashion into mother-fashion is summarized as follows. First in the process of tranference to highfashion in 60s and 70s and hippie-look in 90s the resistance of the hippie style is weakened and only suggested through the outer look. Second the hippie style which reappeared in the high fashion and mother fashion in 90s are layered look military uniform mode flower print grunge look romantic look peasant look ethnic look gypsy style handicraft ornaments working suit style handicraft ornaments working suit style and the use of the see-through cloth. Third the fact that the popular and high fashion were influenced by anti fashion in 60s proves filter-up theory in fashion adaption theory. As I examined before the ideology of the hippies are faded in high fashion in 60s-70s and hippie-look in 90s. The symbolic meaning of the hippie style is also weakened and only presented as a fashion trend.

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The p90rsk-mediated signaling of ethanol-induced cell proliferation in HepG2 cell line

  • Kim, Han Sang;Kim, Su-Jin;Bae, Jinhyung;Wang, Yiyi;Park, Sun Young;Min, Young Sil;Je, Hyun Dong;Sohn, Uy Dong
    • The Korean Journal of Physiology and Pharmacology
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    • v.20 no.6
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    • pp.595-603
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    • 2016
  • Ribosomal S6 kinase is a family of serine/threonine protein kinases involved in the regulation of cell viability. There are two subfamilies of ribosomal s6 kinase, (p90rsk, p70rsk). Especially, p90rsk is known to be an important downstream kinase of p44/42 MAPK. We investigated the role of p90rsk on ethanol-induced cell proliferation of HepG2 cells. HepG2 cells were treated with 10~50 mM of ethanol with or without ERK and p90rsk inhibitors. Cell viability was measured by MTT assay. The expression of pERK1, NHE1 was measured by Western blots. The phosphorylation of p90rsk was measured by ELISA kits. The expression of Bcl-2 was measured by qRT-PCR. When the cells were treated with 10~30 mM of ethanol for 24 hour, it showed significant increase in cell viability versus control group. Besides, 10~30 mM of ethanol induced increased expression of pERK1, p-p90rsk, NHE1 and Bcl-2. Moreover treatment of p90rsk inhibitor attenuated the ethanol-induced increase in cell viability and NHE1 and Bcl-2 expression. In summary, these results suggest that p90rsk, a downstream kinase of ERK, plays a stimulatory role on ethanol-induced hepatocellular carcinoma progression by activating anti-apoptotic factor Bcl-2 and NHE1 known to regulate cell survival.

Thickness Effect on the Compressive Strength of T800/924C Carbon Fibre-Epoxy Laminates (탄소/에폭시 복합재판의 압축강도 두께효과에 대한 연구)

  • Kong C.;Lee J.;Soutis C.
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2004.04a
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    • pp.173-177
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    • 2004
  • In this study, the effect of laminate thickness on the compressive behaviour of composite materials was investigated through systematic experimental work using the stacking sequences, [04]ns, [45/0/-45/90]ns and [45n/0n/-45n/90n]s (n = 2 to 8). The stacking sequence effects on failure strength of multidirectional laminates were examined. For this purpose, two different scaling techniques were used; (1) ply-level technique [45n/0n/-45n/90n]s and (2) sub laminate level technique [45/0/-45/90]ns. An apparent thickness effect existed in the lay-up with blocked plies, i.e. unidirectional specimens $([0_4]ns)$ and ply-level scaled multidirectional specimens ([45n/0n/-45n/90n]s). From the investigation of the stacking sequence effect, the strength values obtained from the sub laminate level scaled specimens were slightly higher than those obtained from the ply level scaled specimens. The measured failure strengths were compared with the predicted values

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