• Title/Summary/Keyword: stabilizing layer

검색결과 78건 처리시간 0.023초

대절토사면에 보강된 억지말뚝의 활동억지효과에 관한 연구 (Reinforcement Effect of Stabilizing Piles in Large-scale Cut Slops)

  • 홍원표;한중근;송영석;신도순
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2003년도 사면안정학술발표회
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    • pp.65-81
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    • 2003
  • During the last few decades in Korea, the development of hillside or mountain areas has rapidly increased for infrastructure construction such as railroads, highways and housing. Many landslides have occurred during these constructions. Also, the amount and scale of damage caused by landslides have increased every year. In the case of Far East Asia including Korea, the damage of landslides is consequently reported during the wet season. In this paper, the effect of stabilizing piles on slope stability is checked and the behavior of slope soil and piles are observed throughout the year by field measurements in the large-scale cut slopes. In particular a large-scale cut slope situated on the construction site for the express highway in Donghae, Korea. First of all, The behavior of the slope soil was measured by inclinometers during slope modification. Landslides occurred in this area due to the soil cutting for slope modification. The horizontal deformations of slope soil gradually increased and rapidly decreased at depth of sliding surface indicating that the depth of sliding surface below the ground surface can be predicted. On the basis of being able to predict the depth of the sliding surface, stabilizing piles were designed and constructed in this slope. To ensure the stability of the reinforced slope using stabilizing piles, an instrumentation system was installed. The maximum deflection of piles is measured at the pile head and it is noted that the piles deform like deflection on a cantilever beam. The maximum bending stress of piles is measured at the soil layer. The pile above the soil layer is subjected to lateral earth pressure due to driving force of the slope, while pile below soil layer is subjected to subgrade reaction against pile deflection. As a result of research, the effect and applicability of stabilizing piles in large-scale cut slopes could be confirmed sufficiently.

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스테인레스 안정화 층을 갖는 YBCO Coated Conductor의 전류 제한 특성에 관한 연구 (Study on current limiting characteristics of YBCO coated conductor with stainless steel stabilizer layer)

  • 두호익;김민주;두승규;김용진;이동혁;한병성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 하계학술대회 논문집
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    • pp.365-366
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    • 2009
  • This study researched into the manufacture of current-limit module of using YBCO coated conductor. Regarding over-current of exceeding the critical current, the quench characteristics were researched according to the stabilizing layer through tendency in resistance, which is generated in conductor, by applying over-current to YBCO coated conductors, which have stabilizing layer. YBCO coated conductors, which were used in experiment, include one kind such as the conductor, which used stainless as the stabilizing layer. The critical current is 70 A. And, the critical temperature is with 90 K. First of all, the quench generation was researched under over-current of exceeding the critical current by using this YBCO coated conductors. The tendency of a rise in the detected voltage according to the applied current was measured. And, the tendency of a rise in resistance through voltage-current curve was measured. As a result, the point of time in thermal quench of conductor, which has stainless as the stabilizing layer, could be confirmed to be fast.

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안정화 층을 갖는 YBCO Coated Conductor와 BSCCO 선재의 결합이 과전류 통전 특성에 미치는 영향 (Effect of Transport Current Properties on Connecting of YBCO Coated Conductor having Stabilizer Layer and BSCCO Tape)

  • 두호익;김민주;박충렬;두승규;김용진;한병성
    • 한국전기전자재료학회논문지
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    • 제21권10호
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    • pp.950-953
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    • 2008
  • YBCO coated conductor called the second-generation superconducting tapes have resistance increase significantly more than BSCCO tapes in terms of the speed or amount when quench occurs, they may have different ranges of application. Such characteristics are thought to get different properties by selection of stabilizing materials in manufacturing superconducting tapes. It is important in selecting superconducting tapes which will be applied to power devices in the future. In this study, one kind of BSCCO tapes and two kinds of YBCO CC with different stabilizing materials and one kind of YBCO CC with non stabilizing materials were used to compare and examine transport characteristics in flux-flow state and quench state with each tape joint of HTS tapes.

대규모 절개사면에 설치된 억지말뚝의 거동 (The Behavior of Stabilizing Piles installed in a Large-Scale Cut Slope)

  • 송영석;홍원표
    • 지질공학
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    • 제19권2호
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    • pp.191-203
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    • 2009
  • 본 연구에서는 대규모 절개사면에서 억지말뚝의 효과를 확인하고, 사면과 억지말뚝의 거동을 조사하였다. 먼저, 사면의 절토공사시 경사계를 이용하여 사면지반의 거동을 조사하였다. 계측결과 사면지반의 수평변위는 점차적으로 증가하고, 사면활동면의 발생위치에서 급격히 감소하는 것으로 나타났다. 이를 통하여 사면활동깊이의 예측이 가능하였다. 사면활동면의 예측을 통하여 억지말뚝의 설계와 시공이 수행되었다. 그리고 억지말뚝으로 보강된 절개사면에 대하여 각종 계측시스템을 적용하여 억지말뚝의 거동을 조사하였다. 계측결과 억지말뚝의 수평변위는 켄틸레버보의 변형형상과 유사하게 발생되었으며, 말뚝두부의 철근콘크리트보의 설치로 인하여 두부의 수평변위 억제효과를 확인할 수 있다. 억지말뚝의 최대휨응력이 발생되는 깊이는 대상지반의 상부토사층이 존재하는 깊이와 유사한 것으로 나타났다. 또한, 쏘일네일링 시공을 위한 억지말뚝 전면부 사면굴착시 억지말뚝의 수평변위가 증가함을 알 수 있다. 본 연구를 통하여 대규모 절개사면에 대하여 억지말뚝의 적용성 및 효과를 확인할 수 있다.

중금속 오염토양 안정화층 시공을 위한 원위치 교반방식과 혼합포설방식의 효과비교 (Comparison the Effect of In-situ Mixing Method and Mixed Laying Method for Construction of Stabilizing Layer on Heavy Metal Contaminated Soil)

  • 이상무;김진환;윤여준;김윤수;박남서
    • 터널과지하공간
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    • 제25권6호
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    • pp.505-514
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    • 2015
  • 본 연구에서는 기존 오염토양 안정화처리 시공방법의 문제점에 대한 해결을 위하여 개발한 혼합포설방식 안정화장비의 현장 적용성 및 시공성을 현장실증시험 및 실내시험을 통하여 검증하였다. 현장 실증시험을 통하여 안정화장비의 현장 적용성을 확인하였으며, 현장 교반토의 석회석 분포 및 CaO 함량 분석 등의 실내시험을 통하여 기존 오염토양 안정화처리 시공방법에 비해 개발된 안정화장비 시공방법의 안정화제 교반성이 더 우수한 것을 확인하였다.

슈퍼캐패시터를 이용한 자동차 전압 안정화 모듈 (Vehicle Voltage Stabilizing Module Using Supercapacitors)

  • 박석희;정규원
    • 한국생산제조학회지
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    • 제24권1호
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    • pp.124-129
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    • 2015
  • The performance of a passenger vehicle has been greatly improved recently owing to the intensive use of electronic controllers. Many components of a vehicle, including the engine, are controlled by electronic systems installed in the vehicle. Therefore, the electrical power required for such electronics has increased significantly. However, the electrical power generated by the vehicle's alternator, operated by the engine, is limited, and when the vehicle is started, a large instantaneous current is required. The voltage of the vehicle electrical system fluctuates to a very low level, then, it is gradually recovered. This case is very severe and can even cause damage to electronic systems. In this study, a voltage-stabilizing module comprising electric double layer supercapacitors, which could alleviate the voltage variation, was developed and tested.

Numerical study of the effect of periodic jet excitation on cylinder aerodynamic instability

  • Hiejima, S.;Nomura, T.
    • Wind and Structures
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    • 제5권2_3_4호
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    • pp.141-150
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    • 2002
  • Numerical simulations based on the ALE finite element method are carried out to examine the aerodynamics of an oscillating circular cylinder when the separated shear flows around the cylinder are stimulated by periodic jet excitation with a shear layer instability frequency. The excitation is applied to the flows from two points on the cylinder surface. The numerical results showed that the excitation with a shear layer instability frequency can reduce the negative damping and thereby stabilize the aerodynamics of the oscillating cylinder. The change of the lift phase seems important in stabilizing the cylinder aerodynamics. The change of lift phase is caused by the merger of the vortices induced by the periodic excitation with a shear layer instability frequency, and the vortex merging comes from the high growth rate, the rapid increase of wave number and decrease of phase velocity for the periodic excitation in the separated shear flows.

Performance evaluation of differently structured RCE-DR GdBCO coated conductor tapes under uniaxial tension at 77 K

  • Diaz, Mark Angelo E.;Shin, Hyung-Seop;Jung, Ho-Sang;Lee, Jaehun
    • 한국초전도ㆍ저온공학회논문지
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    • 제24권1호
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    • pp.13-17
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    • 2022
  • The mechanical properties of REBCO coated conductor (CC) tapes under uniaxial tension are mainly determined by the thick layer Components like the substrate and the stabilizer. Depending on the applications of the CC tapes, it is also needed to externally reinforce thin metallic foils to one side or both sides of the CC tapes. This study investigated the effect of additional stabilizer layers or lamination on the electrical resistivity and electromechanical properties in RCE-DR processed GdBCO CC tapes with different structures. The strain/stress tolerance of Ic in differently processed 12 mm-wide REBCO CC tapes under uniaxial tension at 77 K and self-field could be determined by the loading-unloading scheme. As a result, Sn-Cu stabilized CC tape showed a significant decrease in mechanical properties due to its soft but thick stabilizing layer. However, similar electromechanical properties have been observed on both Sn-Cu and Sn-stabilized CC tapes, the Ic degradation behavior was independent of whether the CC tape has an external reinforcement or different stabilizing layers.

A Fusion Tag to Fold on: The S-Layer Protein SgsE Confers Improved Folding Kinetics to Translationally Fused Enhanced Green Fluorescent Protein

  • Ristl, Robin;Kainz, Birgit;Stadlmayr, Gerhard;Schuster, Heinrich;Pum, Dietmar;Messner, Paul;Obinger, Christian;Schaffer, Christina
    • Journal of Microbiology and Biotechnology
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    • 제22권9호
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    • pp.1271-1278
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    • 2012
  • Genetic fusion of two proteins frequently induces beneficial effects to the proteins, such as increased solubility, besides the combination of two protein functions. Here, we study the effects of the bacterial surface layer protein SgsE from Geobacillus stearothermophilus NRS 2004/3a on the folding of a C-terminally fused enhanced green fluorescent protein (EGFP) moiety. Although GFPs are generally unable to adopt a functional confirmation in the bacterial periplasm of Escherichia coli cells, we observed periplasmic fluorescence from a chimera of a 150-amino-acid N-terminal truncation of SgsE and EGFP. Based on this finding, unfolding and refolding kinetics of different S-layer-EGFP chimeras, a maltose binding protein-EGFP chimera, and sole EGFP were monitored using green fluorescence as indicator for the folded protein state. Calculated apparent rate constants for unfolding and refolding indicated different folding pathways for EGFP depending on the fusion partner used, and a clearly stabilizing effect was observed for the SgsE_C fusion moiety. Thermal stability, as determined by differential scanning calorimetry, and unfolding equilibria were found to be independent of the fused partner. We conclude that the stabilizing effect SgsE_C exerts on EGFP is due to a reduction of degrees of freedom for folding of EGFP in the fused state.