• 제목/요약/키워드: Relative stability

검색결과 913건 처리시간 0.026초

무시멘트형 대퇴스템에서 원위부 압박 정도에 따른 생체역학적 특성 (Biomechanical characteristics of the distal filling effects in cementless femoral stem)

  • 박상석;박재원;채수원
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집A
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    • pp.387-392
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    • 2000
  • In cementless total hip replacement(THR), an initial stability of the femoral component is important to long term fixation of femoral stem. The initial stability has close relationship with the relative displacement of prosthesis and spongy bone at the proximal of femur. After implantation of the prosthesis. the surrounding bone is partially shielded from load carrying and starts to resort. Stress shielding is the cause of the loss of proximal bone. Assessing stress distribution of femur is important to predict stress shielding. The initial stability and the stress shielding were investigated for two loading conditions approximating a single leg stance and a stair climbing. Three types of stems were studied by the finite element method to analyze the biomechanical effects of distal filling of cementless femoral stems, Three types of stems employed are a distal filling stem, a distal flexible stem, and a distal tapered stem.

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색상대비 물방울무늬의 크기와 면적비 변화에 따른 원피스 드레스 착용자의 이미지 연구 (A Study of the Changes in Dress Wearers' Images in Relationto the Changes in the Size and Area Ratio of Polka Dots Relative to Coloration)

  • 김선미;정수진
    • 복식
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    • 제58권6호
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    • pp.54-68
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    • 2008
  • The purpose of this study is to investigate the effect of dot pattern size(0.8, 1.8, 2.5, 5, 8), color combination(BG/R, Y/B), area-ratio on image formation. Sets of stimulus and response scales(7 point semantic) were used as experimental materials. The stimuli were 20 color pictures manipulated with the combination of dot pattern size, color combination, and area-ratio using computer simulation. The subjects were 240 female undergraduates living in Gyeongnam-do. Image factor of the stimulus was composed of 5 different components, visibility, attractiveness, cuteness, stability and high class image. In the cuteness, color combination, dot pattern size showed independent effect. In the stability, area-ratio, dot pattern size showed independent effect. Interaction effects of color and area-ratio combination was significant on cuteness. For visibility image 8cm yellow dot/blue background, for attractiveness image BG/R coloration, for cuteness image Y/B coloration and for stability image 0.8cm yellow dot/blue background were effective. According to the variation of dot pattern size, color combination and area-ratio, it was investigated that the images for a dress wearer were expressed diversely, were shown differently in image dimensions, and could be produced to different images.

전력계통의 미소신호안정도 상정사고 해석 (Contingency Analysis for Small Signal Stability of Power Systems)

  • 심관식;김용구;문채주
    • 조명전기설비학회논문지
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    • 제17권3호
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    • pp.127-137
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    • 2003
  • 논문에서는 대규모 계통의 미소신호안전도 평가 및 해석을 위해 고유치 감도/perturbation 이론에 근거한 상정사고 지표를 제안하였으며 이를 실제 계통에 적용한 결과를 기술하였다. 선로정수와 제어기점수에 대한 미소신호 안정도 상정사고 지표를 제시하였고 이로부터 심각한 저주파진동 문제를 발생할 수 있는 파라메타들을 선택하였다. 또한 각 발전기의 발전량 증감에 대한 고유치 변화로부터 미소신호안정도 상정사고를 일으킬 수 있는 발전기들을 선택하였다. 이 논문에서는 모든 결과들을 2000년 KEPCO 실계통의 시간영역해석과 비교 검증하여 제안한 미소신호안정도 상정사고 해석법이 정확함을 확인하였다.

Numerical Study of Unsaturated Infinite Slope Stability regarding Suction Stress under Rainfall-induced Infiltration Conditions

  • Song, Young-Suk;Hwang, Woong-Ki
    • 지질공학
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    • 제24권1호
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    • pp.1-8
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    • 2014
  • Numerical stability analysis of an unsaturated infinite slope under rainfall-induced infiltration conditions was performed using generalized effective stress to unify both saturated and unsaturated conditions The soil-water characteristic curve (SWCC) of sand with a relative density of 75% was initially measured for both drying and wetting processes. The hydraulic conductivity function (HCF) and suction stress characteristic curve (SSCC) were subsequently estimated. Under the rainfall-induced infiltration conditions, transient seepage analysis of an unsaturated infinite slope was performed using the finite element analysis program, SEEP/W. Based on these results, the stability of an unsaturated infinite slope under rainfall-induced infiltration conditions was examined in relation to suction stress. According to the results, the negative pore-water pressure and water content within the slope soil changed over time due to the infiltration. In addition, the variation of the negative pore-water pressure and water content led to a variation in suction stress and a subsequent change in the slope's factor of safety during the rainfall period.

Effects of Food Polysaccharides and Seaweed Calcium on the Physicochemical Properties of Prickly Pear Extract Fermented by Lactobacillus rhamnosus LS

  • Son, Min-Jeong;Kwon, Oh-Sik;Lee, Sam-Pin
    • Preventive Nutrition and Food Science
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    • 제9권3호
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    • pp.206-212
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    • 2004
  • Prickly pear extract (PPE) was fermented by Lactobacillus rhamnosus LS at 3$0^{\circ}C$ for 2 days. To improve the physicochemical properties of fermented PPE, it was fortified with food polysaccharides (0.2 %) or seaweed calcium before lactic acid fermentation. The viable cell counts, flow behavior, titratable acidity and color stability of fermented PPE were evaluated during 4 weeks of cold storage. Addition of xanthan gum or glucomannan increased the apparent viscosity and acid production, viable cell counts and red color of PPE were also well maintained during the cold storage. However, fermenting PPE with gellan gum resulted in a decrease in relative absorbance, indicating lower color stability. In particular, PPE fortified with carrageenan or alginic acid showed reduced acid production and lower viable cell counts. Addition of seaweed calcium at a 0.1 % level had positive effects on color stability, and helped maintain viable cell counts of 4.1 ${\times}$ 10$^{9}$ CFU/mL. This study demonstrated that xanthan gum could be used as a good thickening agent and stabilizer for retaining viable cell counts and red color during the cold storage in PPE fermented by lactic acid bacteria.

Wind Tunnel Test를 통한 Wind Moment의 적용 사례 (Application of Wind Heeling Moment with Wind Tunnel Test)

  • 김진호;이상열;박세일;김양수
    • 대한조선학회 특별논문집
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    • 대한조선학회 2015년도 특별논문집
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    • pp.74-78
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    • 2015
  • When floating platform or drilling unit is located at operating station during its design life, it has to have the sufficient stability considering external environment. To evaluate whether offshore structure is complied with the required design criteria for intact stability, the factors which decrease the righting moment have to be considered. Wind heeling moment is one of main factors because the direction is opposite to the righting moment. According to 2009 MODU CODE (Code for the construction and equipment of Mobile Offshore Drilling Units, 2009), wind heeling moment derived from wind tunnel test on scale model of offshore structure enables to apply as alternative given formula and method in 2009 MODU CODE. However, there is no the specific method for applying data derived from wind tunnel test. Based on the following reasons, this paper presents that the calculation method of wind heeling moment utilizing non-dimensional coefficient relative to wind loads (wind forces and moments) and the comparison with each method applying an example.

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수지해석에 의한 터널의 파괴거동에 미지는 영향분석 (A Study on Effects of Failure Behaviour of Tunnel Using A Numerical Analysis)

  • 김영민
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1999년도 봄 학술발표회 논문집
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    • pp.309-314
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    • 1999
  • In this paper, an application of finite element procedure fur tunnel failure analysis has been studied. The numerical model is applied to the simulation of a series of plane strain laboratory tests on the small scale model of a shallow tunnel. By comparing experimental and numerical results some conclusions are drawn on the effectiveness of the numerical approach. The findings from these numerical experiments show relative differences in the pattern of failure behaviour for shallow tunnels.

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Proton Transfer in Biomolecules Facilitated by Water: Quantum Chemical Investigations

  • Lee, Sung-Yul
    • Bulletin of the Korean Chemical Society
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    • 제32권4호
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    • pp.1117-1124
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    • 2011
  • We present a brief review for theoretical/computational studies of proton transfer processes of some simple biomolecules promoted by microsolvating water molecules. Focus is given on the relative stability of the canonical vs. zwitterionic forms of amino acids, tautomeric forms of the DNA base adenine, and the biologically active vs. inactive forms of nicotine. The biochemical implications of these findings are also discussed.

선박 카고 탱크의 드래프트 보정된 레벨, 볼륨 측정 (Draft Corrected Level & Volume Measurement for Ship's Cargo Tank)

  • 정성진;최우진;지석준
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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    • pp.1077-1082
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    • 2005
  • It's important that the measurement of ship's draft, cargo tank level & volume is relative to ship's stability and fee. In this paper, the corrected level and volume technique is introduced.

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경(硬)갚셀제(劑)의 흡습(吸濕)에 관(關)한 연구(硏究) (Studies on Water Vapor Absorption through Hard Gelatin Capsules)

  • 박종훈
    • Journal of Pharmaceutical Investigation
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    • 제3권3호
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    • pp.16-19
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    • 1973
  • Stability is impaired in capsules in which there is a transfer of water vapor from capsule to the contents of the capsules. The water vapor transfer between AEA-coated capsules and corn starch, magnesium trisilicate in the closed container was examined. Experimental eguilibrium relative humidity after water vapor transfer and estimated values calculated from a formula of these substances were in close agreement with each other.

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