• Title/Summary/Keyword: Confined

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Variations in Ductility of Shear Wall with Length of Boundary Confinement (단부 횡보강영역에 따른 전단벽 연성도의 변화)

  • 강수민;오재은;박홍근
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.05a
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    • pp.853-858
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    • 2001
  • Experimental studies were peformed to investigate variations in ductility of shear wall with length of boundary confinement. Eight specimens containg different lengths of confinment zone, which model compressive zone in plastic regions of shear walls, were tested against eccentric vetical load. Stress-strain model for confined concrete was used to predict strength and ductility of the specimens, which was compared to the test results. The results obtained show that failure of the compressive zone occurs in a brittle manner when the stress of unconfined zone softened after the ultimate strength were reached. To enhance the ductility of shear walls with concentrated confinement zone such as barbell-type walls, the ultimate strength of the confinement zone needs to be increased, and for shear walls with distributed confinement zone the length of the confinement zone needs to be extended.

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The Experimental Study on Deflation of Air for Top-Down Joint area (역타기둥 이음부의 공기포 배출을 위한 실험적 연구)

  • 임형일;이동하;백민수;박병근;이영도;정상진
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.05a
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    • pp.763-768
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    • 2001
  • The purpose of this study is to research a specific material characteristics of top down concrete at column joint and to reduce column joint opening. Based on the established top down study, the experiment to apply an real construction case is performed. When the concrete placed into joint of top down column, raised air bubble is left as opening. This study is examined the incomplete packing reason in the top down column and found to air deflation method. The result of study is below (1) As the method to minimize column opening caused from confined air, it is required that an air exhaust port installation in joint column. (2) From air exhaust port installation, most of air bubble in column part is exhausted. As the concrete placing height is going up, air bubble size is going smaller.

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A Study on the Architectural Change of Traditional Farmhouse in Pocheon Province (포천군 근대 농가의 건축적 변화 연구)

  • 곽동엽
    • Journal of the Korean housing association
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    • v.13 no.2
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    • pp.31-38
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    • 2002
  • The purpose of this study is to investigate the architectural change of the modern Korean farm-houses. Regional boundary of this study is confined to Pocheon-Gun, and the object is mainly forty-two farm-houses as long as sixty years since it was built. An analysis is made on the change of spaces, facilities and finished materials of farm-houses. The results of this study, An-Chae have changed for the more comfortable living conditions through the spatial changes as like the fittest facilities with spatial extension and integration. And in Arae-Chae, unlike An-Chae, the old and unused space often have transformed to the other function and the its facilities remained still unimproved.

The Monitoring Comparative Results of Floodplain Ecosystems in Regulated and Natural Part of the Danube River (Geisling-Passau)

  • Kouzmina, Janna;Treshkin, Sergey;Henrichfreise, Alfons
    • The Korean Journal of Ecology
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    • v.27 no.4
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    • pp.211-216
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    • 2004
  • The complex ecological researches were made in the broad-leaved forest zone of Central Europe in nature reserves and national parks located on the banks of the river (hydrology, vegetation, soils, unconfined ground waters). The natural conditions of terrestrial ecosystems and natural sites were compared along the course of the rivers. The significant negative influence of low-dammed (low-confined hydrotechnic) construction and small reservoirs on vegetation and soils of floodplain was revealed. On the basis of analysis of mean annual water level and flow trends on the multi-years series (60-100 years) of the hydrometric stations on the rivers under consideration the significant influence of natural long-term variability of watering on vegetation dynamics in the floodplains was revealed.

Detection of viability Change of Escherichia coli O157:H7 using Surface Plasmon Resonance

  • Park, Gwang-Won;Lee, U-Chang;Lee, Won-Hong;Choe, Jeong-U
    • 한국생물공학회:학술대회논문집
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    • 2003.04a
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    • pp.635-638
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    • 2003
  • For the acute assessment on biological toxicity of wastewater, surface plasmon resonance(SPR) based cell viability detection was performed using gold surface-confined cell as a result of adhesion-modifying chemicals. Escherichia coli O157:H7 (E. coli O157:H7) was investigated after exposure to EDTA. Cells were immobilized on gold coated slide glass for SPR analysis by the method of cross-linking carboxyl group on the bacterial surface with amine group of poly-L-lysine that had been coupled to the gold surface modified by a self-assembled monolayer of 11-mercaptounde canoic acid (11-(MUA)). Reflective intensity of each flow step was changed with respect to confect of ethylenediaminetetraacetic acid (EDTA) disodium salt and phosphate-buffered saline (PBS) solution. The proposed detection technique can be used for biological toxicity test.

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Flying Characteristics of Running Tape above Rotating Head (I) (회전헤드에 대한 주행테이프의 부상특성 ( I ))

  • 민옥기;김수경
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.2
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    • pp.523-536
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    • 1991
  • This dissertation analyzes the running mechanism of flexible and thin tape above rotating head through the numerical simulation and the experiment. The scope of analysis is confined to the phenomena of two dimensional elasto hydrodynamic lubrication between the protruded bump on a rotating cylinder and the running tape. This model is based on the elastic deformation equation of plate and shell and Reynolds equation. Finite difference method is employed as a numerical technique to calculate (1) the distribution of pressure between the running tape and rotating bump and (2) the vertical deformation of elastic thin tape over he rotating bump under hydrodynamic pressure. In numerical analyses, the effects of bump size on flying characteristics of the tape were evaluated and examined considering the influence of tension and stiffness of tape.

Transmission Electron Microscopy Study of Stacking Fault Pyramids Formed in Multiple Oxygen Implanted Silicon-on-Insulator Material

  • Park, Ju-Cheol;Lee, June-Dong;Krause, Steve J.
    • Applied Microscopy
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    • v.42 no.3
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    • pp.151-157
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    • 2012
  • The microstructure of various shapes of stacking fault pyramids (SFPs) formed in multiple implant/anneal Separation by Implanted Oxygen (SIMOX) material were investigated by plan-view and cross-sectional transmission electron microscopy. In the multiple implant/anneal SIMOX, the defects in the top silicon layer are confined at the interface of the buried oxide layer at a density of ${\sim}10^6\;cm^{-2}$. The dominant defects are perfect and imperfect SFPs. The perfect SFPs were formed by the expansion and interaction of four dissociated dislocations on the {111} pyramidal planes. The imperfect SFPs show various shapes of SFPs, including I-, L-, and Y-shapes. The shape of imperfect SFPs may depend on the number of dissociated dislocations bounded to the top of the pyramid and the interaction of Shockley partial dislocations at each edge of {111} pyramidal planes.

A Study on the optimum covariance matrix to smart antenna (스마트 안테나에서 최적 공분산 행렬 연구)

  • Lee, Kwan Hyoung;Song, Woo Young;Joo, Jong Hyuk
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.5 no.1
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    • pp.83-88
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    • 2009
  • This paper consider the problem of direction of arrival(DOA) estimation in the presence of multipath propagation. The sensor elements are assumed to be linear and uniformly spaced. Numerous authors have advocated the use of a beamforming preprocessor to facilitate application of high resolution direction finding algorithms The benefits cited include reduced computation, improved performance in environments that include spatially colored noise, and enhanced resolution. Performance benefits typically have been demonstrated via specific example. The purpose of this paper is to provide an analysis of a beamspace version of the MUSIC algorithm applicable to two closely spaced emitters in diverse scenarios. Specifically, the analysis is applicable to uncorrelated far field emitters of any relative power level, confined to a known plane, and observed by an arbitrary array of directional antenna. In this paper, we researched about optimize beam forming to smart antenna system. The covariance matrix obtained using fourth order cumulant function. Simulations illustrate the performance of the techniques.

Monochlorination of Methane over Pt/NaY-zeolite Catalysts with High Platinum Dispersion (고분산도의 백금이 담지된 Pt/NaY 제올라이트 촉매상에서 메탄의 단일염소화 반응)

  • Lee, Dong-Keun
    • Applied Chemistry for Engineering
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    • v.2 no.3
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    • pp.238-245
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    • 1991
  • Chlorination of methane was carried out over the Pt/NaY zeolite catalysts having different dispersion and location. On the finely dispersed platinum particles inside the zeolite methylchloride was the sole product, while on the large platinum ones outside surface of the zeolite all four chloromethanes were produced. Besides the role of highly dispersed platinum particles, the confined volume of the supercages in the support seems to have played another role on the exclusive production of methylchloride by restricting the further chlorination.

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A Study on Survey for Technology Forecasting using Delphi in Animal Science and Veterinary Medicine (축산 . 수의분야의 델파이 기술예측조사에 관한 연구)

  • Cho, K.T.;Paik, I.K.;Cho, Y.W.;Lee, J.I.
    • Journal of Animal Science and Technology
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    • v.46 no.3
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    • pp.479-494
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    • 2004
  • The study was designed to forecast and derive future core technologies using Delphi method for Korean livestock industry. The technologies will make livestock industJy a core and strategic industry that has high value-added sector in 21 century. Questions were given to specialists of each technology in order to survey importance, realization time. level of R&D in Korea and foremost countries, leading group of R&D, effective policy, etc. for each technology. The target of the survey for Delphi is confined to specialists in the area of Animal Science and Veterinary Medicine. 90 core technologies were derived and 62 specialists answered the questionnaire.