• 제목/요약/키워드: Surface Stability

검색결과 3,597건 처리시간 0.033초

SEISMIC STABILITY OF SATURATED REINFORCED SOIL WALLS

  • Kuwano, Jiro;Izawa, Jun
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 추계 학술발표회 3차
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    • pp.66-71
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    • 2010
  • This paper studies the effect of saturation of backfill on the seismic stability of reinforced soil walls (RSWs) using centrifuge shaking table tests. For comparison, degradation of static stability and seismic stability of a RSW under unsaturated condition was also investigated. Test results showed that the RSW under saturated condition had enough static stability. However, seismic stability of saturated RSW significantly decreased as compared with that under unsaturated condition. The saturated model RSW did not collapse, though it showed large deformation. It maintained sufficient stability after shakings although a clear slip surface appeared in the backfill. Finally, it is discussed how to evaluate residual stability of RSWs damaged by earthquakes with test results and the simple evaluation method proposed by authors.

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크기가 제한된 입력을 갖는 가변구조제어 시스템을 위한 개선된 안정 영역 추정값 (An Improved Estimate of the Asymptotic Stability Region for the Uncertain Variable Structure Systems with Bounded Control)

  • 최한호
    • 제어로봇시스템학회논문지
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    • 제11권6호
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    • pp.492-495
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    • 2005
  • This paper deals with the problem of estimating the asymptotic stability region(ASR) of uncertain variable structure systems with bounded control. Using linear matrix inequalities(LMIs) we estimate the ASR and we show the exponential stability of the closed-loop control system in the estimated ASR. We show that our estimate is always better than the estimate of [3].

NFL-FOO에 기준한 SMC의 안정도 증명 : Part 5 (Stability Proof of NFL-FOO-based SMC : Part 5)

  • 이상성;박종근;이주장
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 C
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    • pp.985-987
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    • 1998
  • This paper presents a stability proof for the nonlinear feedback linearization-full order observer-based sliding mode controller (NFL-FOO-based SMC). The closed-loop stability is proved by a Lyapunov function candidate using an addition form of the sliding surface vector and the estimation error.

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NFL-ROO/SMC의 안정도 증명 : Part 2 (Stability Proof of NFL-ROO/SMC : Part 2)

  • 이상성;박종근;이주장
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 C
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    • pp.976-978
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    • 1998
  • This paper presents the stability proof of a nonlinear feedback linearization-reduced order observer/sliding mode controller (NFL-ROO/SMC). The closed-loop stability is proved by a Lyapunov function candidate using an addition form of the sliding surface vector and the estimation error.

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NFL-O/SMMFC의 안정도 증명 : Part 3 (Stability Proof of NFL-O/SMMFC : Part 3)

  • 이상성;박종근;이주장
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 C
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    • pp.979-981
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    • 1998
  • This paper presents a stability proof for the nonlinear feedback linearization-observer/sliding mode model following controller (NFL-O/SMMFC). The separation principle is derived, and the closed-loop stability is proved by a Lyapunov function candidate using an addition form of the sliding surface vector and the estimation error.

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NFL-ROO에 기준한 SMC의 안정도 증명 : Part 6 (Stability Proof of NFL-ROO-based SMC : Part 6)

  • 이상성;박종근;이주장
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 C
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    • pp.988-990
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    • 1998
  • This paper presents the stability proof of a nonlinear feedback linearization-reduced order observer-based sliding mode controller (NFL-ROO-based SMC). The closed-loop stability is proved by a Lyapunov function candidate using an addition form of the sliding surface vector and the estimation error.

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NFL-O에 기준한 SMMFC의 안정도 증명 : Part 7 (Stability Proof of NFL-O-based SMMFC : Part 7)

  • 이상성;박종근;이주장
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 C
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    • pp.991-993
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    • 1998
  • This paper presents a stability proof for the nonlinear feedback linearization-observer-based sliding mode model following controller (NFL-O-based SMMFC). The closed-loop stability is proved by a Lyapunov function candidate using an addition form of the sliding surface vector and the estimation error.

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온도(溫度)가 가토(家兎) 폐포표면(肺胞表面) 활성물질(活性物質)의 활성도(活性度)에 미치는 영향(影響) (Effects of Temperature on the Activity of Pulmonary Surfactant of the Rabbit)

  • 권굉보
    • The Korean Journal of Physiology
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    • 제7권2호
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    • pp.1-8
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    • 1973
  • 온도(溫度)에 대(對)한 폐포표면활성물질(肺胞表面活性物質)의 활성도(活性度)의 태도(態度)를 구명(究明)코져 가토(家兎)의 좌측(左側) 폐장(肺臟)을 적출(摘出)하여 생리적(生理的) 식염수(食鹽水)로 폐포세척액(肺胞洗滌液)을 작성(作成)하여 4 C에 1, 5, 10, 15, 30 및 40일간(日間) 방치(放置)한 군(群)과 20 C에 1, 2, 3, 4, 5 및 7일간(日間) 방치(放置)한 군(群) 및 정상가토(正常家兎)를 4 C에 4, 8, 12 및 24 시간(時間) 노출(露出)한 후(後) 좌측(左側) 폐장(肺臟)을 적출(摘出)하고 폐포세척액(肺胞洗滌液)을 작성(作成)한 군(群)에서 그 표면장력(表面張力)을 측정(測定)하여 정상가토(正常家兎)의 그것과 비교(比較) 결과(結果)는 다음과 같다. 1) 정상가토(正常家兎)의 폐포세척액(肺胞洗滌液)의 최대(最大) 및 최소표면장력(最小表面張力)및 stability index는 각각(各各) $52.5{\pm}2.3,\;4.9{\pm}2.3$ dynes/cm 및 1.65였다. 2) 4 C에 1, 5, 10, 15, 30 및 40일간(日間) 방치(放置)한 폐포세척액(肺胞洗滌液)의 최대(最大) 및 최소표면장력(最小表面張力) 및 stability index는 각각(各各) 정상군(正常群)의 그것과 비교(比較)하여 큰 변화(變化)가 없었으며 40일군(日群)에서는 약간(若干) 증가(增加)하는 경향(傾向)을 보였으나 의의(意義)있는 변화(變化)는 아니었다. 3) 20 C에 1, 2, 3, 4, 5 및 7일간(日間) 방치(放置)한 폐포세척액(肺胞洗滌液)의 최대표면장력(最大表面張力)은 뚜렷한 변화(變化)를 보이지 않았으나 제 7 일(第 7 日)에 약간(若干) 증가(增加)하였으며 최소표면장력(最小表面張力)은 제 2 일(第 2 日)부터 증가(增加)하는 경향(傾向)을 나타내어서 제(第) 5 및 제 7 일(第 7 日)에는 현저(顯著)히 증가(增加)하였으며 그 stability index는 현저(顯著)히 감소(減少)하여 제(第) 5 및 제 7 일(第 7 日)에는 각각(各各) 0.71 및 0.53이었다. 4) 4 C에 4, 8, 12 및 24시간(時間) 노출(露出)한 가토(家兎)에서 얻은 폐포세척액(肺胞洗滌液)의 최대(最大) 및 최소표면장력(最小表面張力) 및 stability index는 각각(各各) 정상군(正常群)의 그것과 비교(比較)하여 큰 변화(變化)를 나타내지 않았으나 제(第)12시간(時間)에서 최소표면장력(最小表面張力)이 약간(若干) 증가(增加)하는 경향(傾向)을 보였으며 제(第)24시간(時間)에는 다시 정상군(正常群)의 그것과 비슷한 경향(傾向)을 나타내었다.

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Strategies in Protein Immobilization on a Gold Surface

  • Park, Jeho;Kim, Moonil
    • Applied Science and Convergence Technology
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    • 제24권1호
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    • pp.1-8
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    • 2015
  • Protein immobilization on a gold surface plays an important role in the usefulness of biosensors that utilize gold-coated surfaces such as surface plasmon resonance (SPR), quartz crystal microbalance (QCM), etc. For developing high performance biosensors, it is necessarily required that immobilized proteins must remain biologically active. Loss of protein activity and maintenance of its stability on transducer surfaces is directly associated with the choice of immobilization methods, affecting protein-protein interactions. During the past decade, a variety of strategies have been extensively developed for the effective immobilization of proteins in terms of the orientation, density, and stability of immobilized proteins on analytical devices operating on different principles. In this review, recent advances and novel strategies in protein immobilization technologies developed for biosensors are briefly discussed, thereby providing an useful information for the selection of appropriate immobilization approach.

Interfacial and Thermal Characteristics of Natural Fiber Composites Reinforced with Henequen Surface-Treated with EBI

  • ;한성옥;조동환
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2004년도 추계학술발표대회 논문집
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    • pp.88-91
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    • 2004
  • In this study, a number of natural fiber henequen reinforced polymer matrix composites were successfully fabricated by means of a compression molding technique using chopped henequen fibers surface-treated with different electron beam irradiation (EBI) dosages, thermoplastic poly(butylene succinate), thermosetting unsaturated polyester and phenolic resins. Their interfacial and thermal characteristics were studied in terms of interfacial shear strength, fracture surface, dynamic mechanical properties, dimensional stability, and thermal stability using single fiber microbonding test, SEM, DMA, TMA, and TGA. The results show that their interfacial and thermal properties significantly depend on the intensity of EBl treatment on the natural fiber surface.

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