• 제목/요약/키워드: Fiber Type

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보강섬유의 종류에 따른 섬유보강 콘크리트의 휨특성 (Flexural Behavior of Fiber-Reinforced Concrete by Fiber Types)

  • 강영태;김규용;이보경;이상규;김경태;남정수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 추계 학술논문 발표대회
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    • pp.15-16
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    • 2017
  • In this study, the flexural behavior of fiber-reinforced concrete by fiber type were evaluated. As a result, the flexural strength of the hooked steel fiber-reinforced concrete(HSFRC) was lower than that of the amorphous metallic fiber reinforced concrete(AFRC), however it was shown strain-softening behavior by the pull-out of fiber. The flexural strength and the equivalent flexural strength of polyamide fiber-reinforced concrete(PAFRC) were lower than other specimens, but the equivalent flexural strength ratio was similar to that of AFRC. The flexural behavior of the fiber-reinforced concrete was associated with the bonding and pull-out properties of the fiber and matrix depending on the fiber type.

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구성형태(構成形態)에 따른 파티클과 파이버로 제조(製造)한 패널의 물리적 및 기계적 성질 (Physical and Mechanical Properties of Panels Fabricated with Particle and Fiber by Composition Types)

  • 윤형운;이필우
    • Journal of the Korean Wood Science and Technology
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    • 제20권2호
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    • pp.9-22
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    • 1992
  • The aim of this research was to investigate physical and mechanical properties of various composition panels, each fabricated with a ratio of fiber to particle of 2 to 10. Type A consisted of fiber-faces and particle-core in layered-mat system. Type B consisted of fiberboard-faces on particleboard-core. Type C consisted of fibers and particles in mixed-mat system. The results obtained from tests of bending strength, internal bond, screw holding strength and stability were as follows: 1. The bending strength and internal bonding of both the Type A panel and the Type B panel were higher than those of the Type C panel and three-layered particle board. 2. The mechanical properties of the Type C panel showed the lowest values of all composition methods. It seems that the different compression ratios of the particle and fiber interrupted the densification of the fibers when hot pressed. 3. The dimensional stability of layered-mat system panels consising of fiber-faces and particle-core was better the than control particleboard. 4. In composition methods of particle and fiber, layered-composition method was more resonable than mixed-composition. The Type B panel had the highest mechanical properties of all the composition types. 5. The Type A panel was considered the ideal composition method because of its resistance to delamination between the particle-layer and the fiber-layer and because of its lower adhesive content and more effective manufa cturing process.

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나노입자 첨가를 통한 우레탄수지의 캐비테이션 저항 향상 (Addition of nano particle to increase the cavitation resistance of urethane)

  • 이익수;김낙주;박대원
    • 한국응용과학기술학회지
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    • 제31권4호
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    • pp.679-687
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    • 2014
  • 본 연구에서는 캐비테이션에 의한 부식에 강한 도료를 개발하기 위하여 고탄성의 우레탄 수지에 내마모 성능을 향상시키기 위한 첨가제로서 Multi wall과 Single wall type의 Carbon nano tube(CNT)와 Spherical과 Fiber type의 Graphite 나노 입자를 첨가하여 물성과 캐비테이션에 대한 저항성, 작업성 등을 비교 평가하였다. 나노 입자로서 Graphite에서는 캐비테이션 저항성($t_{50}$)이 Spherical type($t_{50}$ 182min)보다는 Fiber type($t_{50}$ 292min)이 높은 캐비테이션 저항성을 갖는 것으로 관찰되었다. 또한 CNT에서는 Single wall type의 캐비테이션 저항성($t_{50}$ 286min)이 Multi wall보다는 더 높은 것으로 관찰되었다. 나노 입자중에서 가격 및 캐비테이션 저항성을 감안하면 가장 최적의 나노 입자는 Fiber type의 Graphite로 관찰되었다. 도료의 작업성 평가에서 수동 작업에 의해 제작된 표면은 매끈한 표면을 가지고 있으나 Spray 작업에 의해 제작된 표면은 표면이 균일하지 않으며 Spray시 발생된 Dust가 표면에 고착된 형태로 관찰되었다.

Organic Solvent Absorption characteristics of Split-type micro fiber fabrics

  • Lee, Kwang-Ju;Kim, Seong-Hun
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
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    • pp.95-95
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    • 2003
  • In this study, the influences of organic solvent viscosity on absorption properties of split-type micro fiber fabrics is examined with real time absorption measurement device built by our research group recently. And the absorption behavior of these fabrics is analyzed by material, fineness, construction, weight, thickness, and density of fabrics.

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주기적인 보행이 성장하는 어린뒷다리부유쥐의 Type II 근육에 미치는 효과 (Effect of Periodic Walking on the Type II Muscle of Growing Suspended Rats)

  • 최명애
    • 대한간호학회지
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    • 제26권2호
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    • pp.271-280
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    • 1996
  • The purpose of this study was to determine the effect of periodic walking during hindlimb suspension on the mass, relative weight, fiber type distribution and cross-sectional area of Type I and II fibers in the developing Type II plantaris muscle. To examine the effectiveness of periodic walking on mass and fiber size, the hindlimbs of young female Wistar rats were suspended (HS group) and half of these rats walked on a treadmill for 45 min/day(15 min every 4 hours) at 5 meters/min at a 15 degree grade(HS-W group) After seven days of hindlimb suspension, the plantaris muscle wet weight was 28.40% significantly smaller(P<0.005) and relative plantaris muscle weight was 26.97% smaller compared with those of control rats(P<0.05). The plantaris muscle wet weight and the relative plantaris muscle weight increased by 46.60% and 49.23% respectively with periodic walking, moreover. the plantaris muscle wet weight and the relative plantaris muscle weight of the HS-W rats recovered to the level of the control rats. No change was observed in fiber type percentage of the developing plantaris muscle following one week of hindlimb suspension or periodic walking during hindlimb suspension. Type I and II fiber cross-sectional areas of the developing plantaris muscle were 42.51% and 43. 68% lower in the HS group than in the control group(p<0.0001), Type I and II fiber cross-sectional areas of the developing plantaris were 30.82% and 45.97% greater in the HS-W group than in the HS group(p<0.0001), whereas Type I and II fiber cross-sectional area of HS-W group were less than those of the control group(P<0.0001) The results suggest that periodic walking can attenuate developing plantaris muscle atrophy induced by hindlimb suspension.

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Relationships of Muscle Fiber Characteristics to Dietary Energy Density, Slaughter Weight, and Muscle Quality Traits in Finishing Pigs

  • Jeong, Jin-Yeon;Kim, Gap-Don;Ha, Duck-Min;Park, Man-Jong;Park, Byung-Chul;Joo, Seon-Tea;Lee, C.-Young
    • Journal of Animal Science and Technology
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    • 제54권3호
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    • pp.175-183
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    • 2012
  • The present study was conducted to investigate the relationships of muscle fiber characteristics to dietary energy density [3.0(Low-E) vs. 3.2 (Med-E) Mcal DE/kg)] and slaughter weight [SW; 110, 125, and 138 kg] in finishing pigs (gilt vs. barrow) using a $2{\times}3{\times}2$ factorial treatment design. Forty-one longissimus dorsi muscle (LM) samples were analyzed histochemically, with growth performance and physicochemical data for the 41 animals and their LM out of 192 animals and 72 LM used in a previous study retrospectively included. The ADG was less (P<0.01) in the Low-E than in the Med-E group (0.93 vs. 0.73 kg) whereas lightness ($L^*$) and redness ($a^*$) of LM were greater in the Low-E group SW did not influence these variables. The diameter and perimeter of the type I (slow-oxidative), type IIA (fast oxido-glycolytic) and type IIB (fast glycolytic) fibers increased with increasing SW whereas densities of the fibers decreased. However, the number and area percentages of the fiber types were not influenced by SW or dietary energy density. The percentage and per-$mm^2$ density of type IIB fibers were negatively correlated with SW (r = -0.33 and -0.57, with P<0.05 and <0.01, respectively), whereas type I fiber number percentage was positively correlated with SW (r = 0.31; P<0.05). Marbling score was negatively correlated (P<0.05) with type I (r = -0.36) and type IIB (r = -0.39) fiber densities. The $a^*$ was correlated (P<0.01) with both type I and type IIB fiber number percentages in the opposite way (r = 0.42 and -0.47, respectively). However, $L^*$ (lightness), drip loss and $pH_{24h}$ were not correlated with the fiber number percentage or density of any fiber type. Collectively, results indicate that muscle fibers grow by hypertrophy during the late finishing period, but that fiber characteristics other than the size are not significantly influenced by dietary energy density or SW.

Performance Comparison Between Harmonically Mode-Locked Ring and Figure-of-Eight Type Fiber Lasers

  • Kim Kyong Hon;Lee Hak Kyu;Min-Yong Jeon;El-Hang Lee;Cheol Soon Song;Ki Un NamKoong
    • 한국광학회지
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    • 제7권4호
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    • pp.386-389
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    • 1996
  • We report on comparative results obtained from harmonically mode-locked laser operations of ring-type and figure-of-eight(F8) type erbium-doped fiber lasers by using a directional-coupler type electro-optic modulator as an active mode-locker. The mode-locked and transform-limited pulses of 10.6 ps width were obtained at harmonics of the fundamental cavity frequency with the F8 type laser while mode-locked laser pulses greater than 15 ps were achieved with the ring type laser.

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고지섬유의 효율적 이용을 위한 Multifractor의 활용분석 (II) - Hole screen을 사용하는 경우 - (Use of Multifractor in the Paper Mills for Recycled Fibers (II) - Hole screen cases -)

  • 서영범;윤혜정;이영준;주용훈
    • 펄프종이기술
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    • 제42권1호
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    • pp.20-25
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    • 2010
  • Fractionation effects of the slot-type and the hole-type screens of mutifractors were studied using a pilot multifractor. We used a slot screen of 0.15 mm, and two hole screens of 1.0 and 2.0 mm, respectively, in the study. We found hole-type screens were more effective for fractionation of fiber furnishes according to their fiber lengths. Slot-type screen was more effective to remove the shives from the accepted fiber furnishes. There existed a high regression coefficient between the fiber length differences and the freeness differences of the accepted and the rejected fiber furnishes.

저융점 복합사에 의해 열융착된 폴리에스테르 직물의 염색 - 헤드타이를 중심으로 - (Dyeing of Thermal Bonded Polyester Fabric by using Low-melting-point Bicomponent Filament Yarn - Head tie -)

  • 지명교;이신희
    • 한국의류산업학회지
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    • 제11권4호
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    • pp.661-666
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    • 2009
  • The purpose of this study is to analyze the dyeability of polyester(PET) fabric by thermal bonding with low melting component of bicomponent fiber and to describe the change of physical properties of thermal bonded PET fabrics. The PET fabrics were prepared with regular PET fiber as warp and bicomponent fiber as weft. The bicomponent fiber of sheath-core type was composed with a regular PET core and low melting PET sheath. The thermal bonding of PET fabric was carried out in pin tenter($195^{\circ}C$) for 60 seconds. In this study, we investigated the dye ability and fastness of the dyed PET fabric. Dye ability of E-type dyestuff is higher than S-type dyestuff. In the case of E- type dyestuff, the saturated dyeing time was 10minutes at $130^{\circ}C$. The washing fastness and light fastness were excellent as 4-5grade.

강섬유 형상별 초고성능 콘크리트 기초 물성 평가 (Evaluation of Fundamental UHPC Properties according to shape of steel fiber)

  • 류금성;고경택;강수태;박정준;강현진;김성욱
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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    • pp.533-534
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    • 2009
  • 연구에서는 초고성능 콘크리트의 섬유 형상에 따라 휨거동특성에 미치는 효과를 평가하였다. 그결과 섬유 형상에 따라 휨강도에 큰 영향을 미치는 것으로 나타났다. 또한 초기균열강도에는 큰 영향을 미치지 않고 물결타입의 강섬유 사용으로 최대 휨강도가 높게 나타났다.

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