• Title/Summary/Keyword: deformability

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Effect of Lateral Reinforcement Details to Seismic Performance of RC Piers having Partial Lap-spliced Longitudinal Bars (중실사각단면 교각의 횡철근 상세에 따른 내진성능)

  • An, Jun-Hyuk;Sun, Chang-Ho;Jeong, Hyeok-Chang;Kim, Ick-Hyun;Lee, Jong-Seok
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.11a
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    • pp.53-56
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    • 2006
  • Due to the bond failure of lap-spliced longitudinal bars very brittle failure is conducted in existing RC columns. This failure can be, however, prevented by providing partial lap spliced longitudinal bars. But the deformability of columns having various lateral confinements is not confirmed yet. In this study scale models with different confinements were tested to investigate characteristics of seismic behaviors. It was confirmed that deformability was increased dramatically with increase of lateral reinforcements.

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The Changes of Erythrocyte Feature and Ca Concentration in Rat Fed the Diet Containing Different Common Oils in Korea : Sesame Oil, Perilla Oil, Rice Bran Oil and Mixed Oil (급원이 다른 식이 지방이 흰쥐의 적혈구 성상 및 Ca 함량에 미치는 영향 -참깨유, 들깨유, 미강유 중심으로-)

  • 김숙희
    • Journal of Nutrition and Health
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    • v.26 no.5
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    • pp.524-531
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    • 1993
  • In this experiment, we investigated the changes of erythrocyte feature and Ca concentration in rat fed the diet containing different common oils in Korea for different feeding periods(4 weeks or 12 weeks), using Korea sesame oil, perilla oil, rice bran oil and mixed oil. W-3/w-6 ratio of each group was 0.001, 1.44, 0.03 and 0.112, respectively. P/S ratio of each group was 9.64, 10.49, 5.58 and 1.68, respectively. Perilla oil(w-3 rich) increased w-3/w-6 ratio of erythrocyte membrane, decreased the amount of trapped Ca and inhibited the decrease of cell volume. These results indicate that in maybe increase erythroyte fluidity and deformability, and affect erythrocyte function. In conclusion, w-3 rich perilla oil affects erythrocyte feature.

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Mechanical characteristics of hollow shear connectors under direct shear force

  • Uenaka, Kojiro;Higashiyama, Hiroshi
    • Steel and Composite Structures
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    • v.18 no.2
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    • pp.467-480
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    • 2015
  • The steel-concrete composite decks have high fatigue durability and deformability in comparison with ordinary RC slabs. Withal, the steel-concrete composite deck is mostly heavier than the RC slabs. We have proposed herein a new type of steel-concrete composite deck which is lighter than the typical steel-concrete composite decks. This can be achieved by arranging hollow sectional members as shear connectors, namely, half-pipe or channel shear connectors. The present study aims to experimentally investigate mechanical characteristics of the half-pipe shear connectors under the direct shear force. The shear bond capacity and deformability of the half-pipe shear connectors are strongly affected by the thickness-to-diameter ratio. Additionally, the shear strengths of the hollow shear connectors (i.e. the half-pipe and the channel shear connectors) are compared. Furthermore, shear capacities of the hollow shear connectors equivalent to headed stud connectors are also discussed.

Effect of Microstructural Factors on the Strength and Deformability of Ferrite-Pearlite Steels with Different Mn and V Contents (Mn 및 V 함량이 다른 페라이트-펄라이트 조직강의 강도와 변형능에 미치는 미세조직 인자의 영향)

  • Hong, Tae-Woon;Lee, Sang-In;Shim, Jae-Hyeok;Lee, Junho;Lee, Myoung-Gyu;Hwang, Byoungchul
    • Korean Journal of Materials Research
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    • v.28 no.10
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    • pp.570-577
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    • 2018
  • This study examines the effect of microstructural factors on the strength and deformability of ferrite-pearlite steels. Six kinds of ferrite-pearlite steel specimens are fabricated with the addition of different amounst of Mn and V and with varying the isothermal transformation temperature. The Mn steel specimen with a highest Mn content has the highest pearlite volume fraction because Mn addition inhibits the formation of ferrite. The V steel specimen with a highest V content has the finest ferrite grain size and lowest pearlite volume fraction because a large amount of ferrite forms in fine austenite grain boundaries that are generated by the pinning effect of many VC precipitates. On the other hand, the room-temperature tensile test results show that the V steel specimen has a longer yield point elongation than other specimens due to the highest ferrite volume fraction. The V specimen has the highest yield strength because of a larger amount of VC precipitates and grain refinement strengthening, while the Mn specimen has the highest tensile strength because the highest pearlite volume fraction largely enhances work hardening. Furthermore, the tensile strength increases with a higher transformation temperature because increasing the precipitate fraction with a higher transformation temperature improves work hardening. The results reveal that an increasing transformation temperature decreases the yield ratio. Meanwhile, the yield ratio decreases with an increasing ferrite grain size because ferrite grain size refinement largely increases the yield strength. However, the uniform elongation shows no significant changes of the microstructural factors.

The Effects of Boyanghwanotang on the Thrombosis Related Factors (보양환오탕(補陽還五湯)이 혈전생성관여인자(血栓生成關與因子)에 미치는 영향(影響))

  • Park, Jong-Hyung;Han, Yang-Hi;Jun, Chan-Yong;Kim, Dong-U;Park, Se-Gi;Lee, Chung-Jung-Hye;Go, Seung-Hi;Go, Jae-Chul;Choi, You-Kyung;Park, Sun-Young
    • The Journal of Internal Korean Medicine
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    • v.21 no.5
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    • pp.829-837
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    • 2000
  • Purpose : To investigate the inhibitory effect of BHE on platelet aggregation and erythrocyte deformability, we performed following experiments. Methods : Concentrated Boyanghwanotang (BHE) was fed to rats for 10days. High dose group was treated with $500{\beta}{\partial}/kg$ and low dose group with $500{\beta}{\partial}/kg$. Results : BHE enhanced the blood filtration rate, reduced the platelet aggregability, inhibited granule release from collagen-stimulated platelet, the prostaglandin syn-thesis in platelet and enhanced erythrocyte deformability. Conclusion : BHE should inhibit thrombos formation due to platlete hyperaggregabili-ty and reduction of erythrocyte deformabi-lity.

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Effect of Fatty Acid on the Membrane Fluidity of Liposomes (지방산 첨가가 리포좀 유동성에 미치는 영향에 관한 연구)

  • Lee, JinSun;Chi, Gyeong-Yup;Lim, JongChoo
    • Applied Chemistry for Engineering
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    • v.28 no.2
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    • pp.177-185
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    • 2017
  • In the present work, the interaction of fatty acid with vesicle membrane of phospholipids was investigated using 3 different kinds of fatty acids such as stearic acid (SA), oleic acid (OA) and linoleic acid (LA). Basically, the same trend has been found in 3 fatty acid systems. The addition of fatty acid produced a close packing of liposome due to the penetration of fatty acid molecules into liposome vesicles, which resulted in a decrease in size and an increase in zeta potential of liposome. However, excessive addition of fatty acid produced a transition from liposomes to aggregates of lipid particles having polymorphic structure. The membrane fluidity, characterized by measuring membrane deformability and fluorescence anisotropy ratio of liposomes, was in good agreement with measurement results of transmission electron microscopy (TEM) and particle size. The minimum size and closest packing of liposome with SA, OA and LA were found when the molar ratios of fatty acid to lecithin were 0.70, 0.50, and 0.25 respectively.

A Study for Shear Deterioration of Reinforced Concrete Beam-Column Joints Failing in Shear after Flexural Yielding of Adjacent Beams (보의 휨항복 후 접합부가 파괴하는 철근콘크리트 보-기둥 접합부의 전단내력 감소에 대한 해석적 연구)

  • Park, Jong-Wook;Yun, Seok-Gwang;Kim, Byoung-Il;Lee, Jung-Yoon
    • Journal of the Korea Concrete Institute
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    • v.24 no.4
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    • pp.399-406
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    • 2012
  • Beam-column joints are generally recognized as the critical regions in the moment resisting reinforced concrete (RC) frames subjected to both lateral and vertical loads. As a result of severe lateral load such as seismic loading, the joint region is subjected to horizontal and vertical shear forces whose magnitudes are many times higher than in column and adjacent beam. Consequently, much larger bond and shear stresses are required to sustain these magnified forces. The critical deterioration of potential shear strength in the joint area should not occur until ductile capacity of adjacent beams reach the design demand. In this study, a method was provided to predict the deformability of reinforced concrete beam-column joints failing in shear after the plastic hinges developed at both ends of the adjacent beams. In order to verify the deformability estimated by the proposed method, an experimental study consisting of three joint specimens with varying tensile reinforcement ratios was carried out. The result between the observed and predicted behavior of the joints showed reasonably good agreement.