• Title/Summary/Keyword: %elongation

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Longitudinal Elongation of Slender Reinforced Concrete Beams Subjected to Cyclic Loading (주기하중을 받는 세장한 철근콘크리트 보의 길이방향 인장변형)

  • Eom, Tae-Sung;Park, Hong-Gun;Kang, Su-Min
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.11a
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    • pp.169-172
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    • 2008
  • Longitudinal elongation develops in reinforced concrete beams that exhibit flexural yielding during cyclic loading. The longitudinal elongation can decrease the shear strength and deformation capacity of the beams. In the present study, nonlinear truss model analysis was performed to study the elongation mechanism of reinforced concrete beams. The results showed that residual tensile plastic strain of the longitudinal reinforcing bar in the plastic hinge is the primary factor causing the member elongation, and that the shear-force transfer mechanism of diagonal concrete struts has a substantial effect on the magnitude of the elongation. Based on the analysis results, a simplified method for evaluating member elongation was developed. The proposed method was applied to test specimens with various design parameters and loading conditions..

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Reological Studies on Cocoon Filament II. Changes of strength and elongation at breaking related to the stretching speed and swelling degree (견사의 탄성적성질에 관한 연구 II. 인장속도 및 팽윤에 따른 파괴강신도의 변화)

  • 남중희
    • Journal of Sericultural and Entomological Science
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    • v.14 no.2
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    • pp.105-112
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    • 1972
  • The effects of the stretching speed and the swelling degree of cocoon filaments on load-elongation curve were tested by tensilon with special attachments. The values of breaking strength, elongation at break and initial tensile strength obtained from load elongation curves are summarized as follows; 1. The breaking strength of the swollen cocoon filament appeared to increase at the high stretching speed, while elongation at break decreased. 2. Load-elongation curve became crinkled at the low speed of stretching. It suggests that both slip and break of the macrofibrils may occur in swelling of cocoon bave. 3. Breaking strength appeared to considerably decrease and elongation at break not to increase in swelling test at 9$0^{\circ}C$ for 60 min. 4. The initial tensile strength was influenced by the stretching speed and swelling degree of cocoon filaments.

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Characterization of Elongation Behavior According to Sewing Conditions for Elastic Bands on Woven Fabrics (비신축성 직물의 고무 밴드 봉제 조건에 따른 신장 특성 분석)

  • Eom, Ran-i;Lee, Yejin
    • Journal of the Korean Society of Clothing and Textiles
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    • v.45 no.4
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    • pp.648-660
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    • 2021
  • This study analyzes how sewing conditions for elastic bands on woven fabrics affect elongation. The directions of the elastic bands were vertical, horizontal, vertical and horizontal crossing, and horizontal and vertical crossing. Intervals between the elastic bands were 3.0 cm and 6.0 cm. The woven fabric was tailored for the elastic band sewing using warp, weft, and bias. Consequently, it was possible to visually confirm elongation differences according to the sewing condition of the elastic bands. A detailed examination demonstrated that the horizontal or vertical placement of elastic bands tailored in a crosswise direction produces high vertical elongation and low horizontal contraction. However, elastic bands sewed in crossing directions, regardless of warp and weft directions, resulted in both high vertical elongation and high horizontal contraction. In all cases, the more elastic bands were used, the higher the horizontal elongation. In conclusion, appropriate placements of elastic bands on woven fabric increases motion convenience.

SHORT-ROOT Controls Cell Elongation in the Etiolated Arabidopsis Hypocotyl

  • Dhar, Souvik;Kim, Jinkwon;Yoon, Eun Kyung;Jang, Sejeong;Ko, Kangseok;Lim, Jun
    • Molecules and Cells
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    • v.45 no.4
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    • pp.243-256
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    • 2022
  • Transcriptional regulation, a core component of gene regulatory networks, plays a key role in controlling individual organism's growth and development. To understand how plants modulate cellular processes for growth and development, the identification and characterization of gene regulatory networks are of importance. The SHORT-ROOT (SHR) transcription factor is known for its role in cell divisions in Arabidopsis (Arabidopsis thaliana). However, whether SHR is involved in hypocotyl cell elongation remains unknown. Here, we reveal that SHR controls hypocotyl cell elongation via the transcriptional regulation of XTH18, XTH22, and XTH24, which encode cell wall remodeling enzymes called xyloglucan endotransglucosylase/hydrolases (XTHs). Interestingly, SHR activates transcription of the XTH genes, independently of its partner SCARECROW (SCR), which is different from the known mode of action. In addition, overexpression of the XTH genes can promote cell elongation in the etiolated hypocotyl. Moreover, confinement of SHR protein in the stele still induces cell elongation, despite the aberrant organization in the hypocotyl ground tissue. Therefore, it is likely that SHR-mediated growth is uncoupled from SHR-mediated radial patterning in the etiolated hypocotyl. Our findings also suggest that intertissue communication between stele and endodermis plays a role in coordinating hypocotyl cell elongation of the Arabidopsis seedling. Taken together, our study identifies SHR as a new crucial regulator that is necessary for cell elongation in the etiolated hypocotyl.

Longitudinal Elongation of Slender Reinforced Concrete Beams Subjected to Cyclic Loading (주기하중을 받는 세장한 철근콘크리트 보의 길이방향 인장변형)

  • Eom, Tae-Sung;Park, Hong-Gun
    • Journal of the Korea Concrete Institute
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    • v.20 no.6
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    • pp.785-796
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    • 2008
  • Longitudinal elongation develops in reinforced concrete beams that exhibit flexural yielding during cyclic loading. The longitudinal elongation can decrease the shear strength and deformation capacity of the beams. In the present study, nonlinear truss model analysis was performed to study the elongation mechanism of reinforced concrete beams. The results showed that residual tensile plastic strain of the longitudinal reinforcing bar in the plastic hinge is the primary factor causing the member elongation, and that the shear-force transfer mechanism of diagonal concrete struts has a substantial effect on the magnitude of the elongation. Based on the analysis results, a simplified method for evaluating member elongation was developed. The proposed method was applied to test specimens with various design parameters and loading conditions.

Forming Characteristics of Laser Welded Tailored Blanks I : Tensile Deformation Characteristics. (레이저 용접 테일러드 블랭크의 기본 성형특성 I : 인장변형 특성)

  • Park, Gi-Cheol;Han, Su-Sik;Kim, Gwang-Seon;Gwon, O-Jun
    • Transactions of Materials Processing
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    • v.7 no.1
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    • pp.23-35
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    • 1998
  • In order to analyze the tensile deformation characteristics of laser welded tailored blanks. laser welded blanks of different thikness and strength combinations were prepared and tensile tests were done. The tensile elongation along the direction perpendicular to weld line of laser welded blanks was reduced as increasing the deformation restraining force (strength X thicknes) ratio between two welded sheets and fracture occurred at weaker side of base sheets if void ration of welded sheets and fracture occurred at weaker side of base sheets if void ratio of weld section was less than 45% The tensile elongation along weld line reached above 90% of the elongation of base material if welding was done perfectly. Total elongation along the direction perpendicular to weld line was able to be predicted by force equilibrium and power law behavior of base sheets and it was related with the deformation of stronger sheet and formability of weaker side.

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Vascular Transition and Hypocotyl Elongation in Soybean(Glycin max) Seedlings (대두(Glycine max) 유식물에서 하배축의 신장과 유관속전이)

  • 강경덕
    • Journal of Plant Biology
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    • v.34 no.4
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    • pp.274-281
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    • 1991
  • The relationship between elongation of hypocotyl and its vascular transition was studied with seedling of Glycine max. the hypocotyl elongation proceeded acropetally from the base of hypocotyl toward the cotyledonary node. The vascular transition did not occur in the basal region of the hypocotyl, which did not nearly elongate, with exarch radial vascular bundles. However, the vascular transition was almost completed at the middle part of the hypocoty, more or less elongated, with endarch collateral vascular bundles. Such bundles also appeared in the uppermost region of the hypocotyl, in which the elongation was the most striking. These results suggested that the vascular transition was related to the hypocotyl elongation and that the transition of primary vascular system in Glycine max seedling was established by rather rapid process. Our observations of the serial sections from root to hypocotyl revealed that the vascular system through the root-hypocotyl-cotyledon was a unit, to which one of the epicotyl that did not participate in transition was superimposed.

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Study on the Synthesis of Wool-blending Fiber Bundle and New Signs of the Curve

  • Ren Yonghua;Yu Jianyong
    • Fibers and Polymers
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    • v.6 no.4
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    • pp.339-342
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    • 2005
  • In this paper, a hand-operating method (tiled test method) of the wool-blending sample is made out, and make use of the method, the test of wool-blending bundle in different blending ratio is accomplished. According to the test data, the synthesis method of the stretch curve is worked out and the synthesis software for the typical stretch curve of wool-blending bundle is designed. Through laboratory hand-operating method, the blending fasciculus applying to fiber bundle test can be obtained in a short time. Calculation for sampling is accomplished in the article. We bring up 9 new signs to describe the characteristics of the curve behind peak for the first time: elongation behind peak (HE), elongation percentage behind peak (HEP), relative elongation rate behind peak (RHE), total break work $(W_a)$, break work behind peak (HW), break work coefficient behind peak (HWC), elongation percentage of half-load behind peak (HEL), load percentage of half-elongation behind peak (HLE), break efficiency behind peak (HEC).

Effect of Elongation on Electrical and Structral Properties of Polyethylene (Polyethylene의 전기적,구조적 성질에 미치는 연신효)

  • 박대희;김동욱;임기성;임기조;이동영;한민구
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.43 no.4
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    • pp.601-606
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    • 1994
  • This paper describes the effect of elongation on electrical properties and molecular structrue of high density polyethylene. Thin polyethylene films films obtained dy roll elongation after extruded at 220$^{\circ}C$ and elongated to draw rations of 16. Crystallinity of polyethylene films was measured by X-Ray diffraction and electrical properties were estimated by conductivity and TSC(Thermal Simulated Current). It was foung that the crystallinity increases and the electrical conductivity decreases as the elongation increases. The elongation dependence of electrical conductivity may be explained by the trap density. Thus, the control of polymer structure and crystallinity makes its properties better and can be applicated in order to get more active properties.

The Properties of Electrical Conduction and Photoconduction in polyphenylene Sulfide(PPS) by Uniaxal Elongation (일축연신에 따른 Polyphenylene Sulfide(PPS)의 전기전도 및 광전도 특성)

  • Lee, Un-Yong;Jang, Dong-Uk;Shin, Tae-Su;Lim, kee-Joe;Ryu, Boo-Hyun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.10
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    • pp.763-767
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    • 1998
  • In this paper, it is investigated how the morphology and electrical properties in Polyphenylene Sulfide(PPS) changed by uniaxial elongation. XRD(X-ray diffraction) pattern shows that interplanar distance and crystallinities are decreased by increasing elongation ratio. electrical conduction mechanism of PPS is explained as Schottky emission mechanism. the electrical current is decreased by increasing elongation ratio. The conductivity is changed considerably above the glass transition temperature around 82(>$^{\circ}C$). The band gap of PPS is evaluated as 3.7~4(eV)

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