• Title/Summary/Keyword: folding strength

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Effects on Mechanical Strength Improvement of Liner Paper using Recycled Fibres from Waste Cotton Clothes (폐 면직물 재활용 섬유를 이용한 라이너지의 강도개선 효과)

  • Hong, Seok-Jun;Park, Jung-Yoon;Kim, Hyoung-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.46 no.6
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    • pp.94-102
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    • 2014
  • The physical and chemical properties of recycled fibers from mixed waste paper are more and more deteriorated because of unknown history of recycling times. In order to improve the mechanical properties of liner paper, the recycled fibers from wasted cotton clothes were used in papermaking process, and their applicabilities were evaluated in several points of fiber modification. Thus, two kinds of fiberizing methods from waste cotton clothes were considered by using rotary sandpaper and grinder mill. Finally, the rotary sandpaper method was relatively desirable in preserving longer fiber length and fibrillated fiber surface. The recycled cotton fibers by swelling treatment with NaOH and bleaching with reductive chemicals were mixed with OCC fibers, and the handsheets were prepared to basis weight of $80g/m^2$ and evaluated the mechanical properties of paper. The fibrous properties showed outstanding results in freeness and WRV improvements by alkali treatment and high brightness by reductive bleaching treatment. The physical and mechanical properties of sheet by mixing OCC fibers and recycled cotton fibers were also highly improved in tensile, burst strength and specially folding resistance.

Effects of Heating Condition and Additives on Rheology of Squid Meat Paste Products (오징어 연제품의 물성에 미치는 가열조건과 첨가제의 영향)

  • 배태진;김해섭;최옥수
    • Journal of Life Science
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    • v.13 no.4
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    • pp.481-491
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    • 2003
  • A squid meat has not been utilized for gel products because of its lower gel forming ability. The objectives of this study were as followed; 1) the optimum heating condition on squid meat paste products and 2) the optimum added level for jelly strength of squid meat paste products. Optimum heating conditions of squid meat kamaboko were as followed; setting (pre-heating) at 15$^{\circ}C$ or 55$^{\circ}C$ for 2 hours and heating at 90$^{\circ}C$ for 60 minutes. Effect for jelly strength of starch additives wheat starch, potato starch and com starch were examined. The jelly strength of heat induced gels differed from the levels of additives. In case of adding starch, potato starch was resulted in the superior jelly strength than the other starchs, wheat starch and corn starch, at any levels. Optimum concentration was 10%(w/w) at every additives. Folding test value was B at added 10% and this value was mean good product. Data of jumbo and flying squid meat paste products added potato starch, corn starch and wheat starch of 10% were shown below, jelly strengths were 858${\pm}$34∼1020${\pm}$37gㆍcm and 966${\pm}$33∼l148${\pm}$45gㆍcm and moisture contents were 72.43∼73.04% and 71.61∼72.78%, respectively. To adding edible agar and sea tangle, showed the highest jelly strength (edible agar>sea tangle, flying squid>jumbo squid) at added 0.5%(w/w) concentration.

Effect of Added Proteins on Rheology of Squid Meat Paste Products (오징어 연제품의 물성에 미치는 단백질류의 영향)

  • 배태진;김해섭;최옥수
    • The Korean Journal of Food And Nutrition
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    • v.16 no.2
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    • pp.138-145
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    • 2003
  • The effects of adding egg white, bovine plasma protein(bpp), gelatin and gluten on the rheological properties of squid meat paste product(squid meat kamaboko) were examined by the measurements of jelly strength, texture, moisture content, water holding capacity(WHC) and folding test. The optimum added levels for jelly strength of squid meat kamaboko were 4% of egg white, 5% of bovine plasma protein, 3% of gelatin and 4% for gluten. However, it is no increase that at added additives of over this concentrations were. Bovine plasma protein gave the highest jelly strength among the all additives at every concentration. Folding tests value of the optimum added levels were all B value. In this case moisture content and water holding capacity were 72.06∼73.78% and 88.53∼91.11% in jumbo squid, also flying squid were 71.91∼72.89% and 90.21∼93.25%, respectively. The additives were increased the jelly strength, hardness and water holding capacity(WHC), and these effects were eliminated by adjusting the water-content to the value of the control sample without additives.

Development of Ultralight Composite Wheelchair Frame (초경량 복합재 의자차 차체 개발)

  • 강지호;김수현;김천곤
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2002.05a
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    • pp.215-218
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    • 2002
  • In this paper, we applied composite material of high specific stiffness and strength to the fabrication of a folding wheelchair frame for the replacement of conventional metal wheelchair frames. A one-body composite frame was designed and the finite element analysis was performed on this design. Some specimens of joint parts were manufactured and strength test was done. With the results of analysis and test, some modification was done and a prototype was produced.

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The Die Design of STS304 Bezel Frame for The Strength Reinforcement in Hemming Process (강도보강용 STS304 베젤 프레임 헤밍 공정의 금형 설계)

  • Kim, G.H.;Lee, S.H.;Kim, B.M.
    • Transactions of Materials Processing
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    • v.17 no.6
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    • pp.436-442
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    • 2008
  • As the structure of a mobile phone becomes thin to catch up with a slim product trend, the structural strength and resistance to shock of TFT-LCD module are getting to be reduced. Hence, TFT-LCD module is the strength reinforced by bezel frame. The bezel frame was produced by the multi hemming processes with several folding parts. The determination of the optimal number of hemming part and structure of bezel frame are very important process parameter to obtain the strength of that. The effect of process parameters on strength of bezel frame was investigated by FEA. Based on the result of FEA, the experiment was performed using manufactured hemming die, the result of the experiment was compared with FEA and verified. Also, three point bending tests were performed to check the strength of bezel frame.

Effect of Soxhlet Extraction Condition on Dewaxing Efficiency of the Beeswax-Treated Paper (속실렛 추출법에 의한 밀랍지의 탈랍처리 효과분석)

  • Choi, Kyoung-Hwa;Jang, Hye-Mi
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.45 no.5
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    • pp.64-70
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    • 2013
  • In this study, the effect of soxhlet extraction on dewaxing of the aged beeswax-treated paper was examined. To do this, soxhlet extraction of the aged beeswax-treated paper performed with different reflux conditions and then measured the dewaxing efficiency and change in the various properties such as tensile strength, folding endurance, color and brightness. Also, an artificial aging test was executed in order to investigate the effect of soxhlet extraction on the preservability of the dewaxed paper. As the result of FT-IR analysis, a peak area of CH and COOH group, which are main band of beeswax, was decreased or removed after soxhlet extraction. The decreasing rate of each peaks were increased depending on reflux time. After dewaxing, the physical property such as MIT type folding endurance and tensile strength was decreased. And $L^*$ value and brightness were increased while $a^*$ and $b^*$ value were decreased due to the remove of color compounds in beeswax. The more color deviation (${\Delta}E$) is expected with higher reflux times. As the result of artificial aging, preservability of two dewaxed papers except of DP_SE(C) sample was higher than that of untreated paper i.e. beeswax-treated paper.

Strength Improvement of Linerboard by impregnation with PVAm (PVAm 함침에 의한 라이너지 강도 향상)

  • Kim, Hyuk-Jung;Won, Jong-Myoung;Cho, Byoung-Uk
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.44 no.1
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    • pp.58-64
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    • 2012
  • As a first step to apply PVAm (polyvinylamine) on packaging paper by surface treatment, three types of linerboards were impregnated with PVAm solution. The effect of PVAm pick-up on strength properties of linerboard was investigated. The pick-up of PVAm was controlled by varying concentration of PVAm solution. It was found that dry tensile strength, tensile energy absorption, burst strength and compressive strength of linerboard were increased by applying PVAm. In addition, wet tensile strength was significantly improved with increasing PVAm pick-up. However, folding endurance was found to be decreased with increasing PVAm pick-up.

Analytical Study to Check Safety of Folding-type Staircase in High Speed Rolling Stock (접이식 고속열차 승강문 스텝의 안전성 확인을 위한 해석적 연구)

  • Lee, Weon-Dae;Park, Sang-Kyu;Lee, Kyung-Kyu;Lee, Jeong-Hun
    • Journal of the Korean Society for Railway
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    • v.17 no.2
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    • pp.87-93
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    • 2014
  • The KTX, running in Korea but imported from Alstom Co. in France, has folding type staircases complying with European standard EN 4752. However, when operating, the step size is only 200mm, while the Korean standard step size is 253mm, a standard reflecting the average value of persons aged 20~60. From the aspect of kinesiology, the current step size can cause falls or slips during embarking and disembarking of passengers because body load is mostly focused on the heel and the current step is much more narrow than the standard size. Thus, we have performed an analytical study to check the safety of folding type staircases on the KTX after re-design.

Effects of relative humidity on the physical properties of PVA impregnated paper (상대습도의 변화가 PVA 함침처리지의 물성에 미치는 영향)

  • Kim, Tae-Young;Joung, Yang-Jin;Kim, Du-Ki;Heo, Yong-Dae;Sung, Yong-Joo
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.42 no.3
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    • pp.37-42
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    • 2010
  • The properties of paper are very susceptible to moisture content originated from relative humidity. This propensity of PVA impregnated paper was investigated in this study. Especially the hardening effect of borax treatment after PVA impregnation on the response of paper sample to the relative humidity was evaluated. When the moisture content was increased with the relative humidity, tensile stretch and tear resistance were increased while tensile strength and stiffness were decreased. A great increase in folding endurance of PVA impregnated paper sample was found at the higher relative humidity. The borax treatment could reduce the response of PVA impregated paper to the relative humidity.

Analysis about Flexural Strength of Steel Plate-Concrete Composite Beam using Folded Steel Plate (Cap) as Shear Connector (절곡 강판(Cap)을 전단연결재로 사용한 강판-콘크리트 합성보의 휨강도 분석)

  • Cho, Tae-Gu;Choi, Byong-Jeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.7
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    • pp.481-492
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    • 2018
  • The steel-plate concrete composite beam is composed of a steel plate, concrete and shear connector to combine two inhomogeneous materials. In general, the steel plate is assembled by welding an existing composite beam. In this study, the SPC beam was composed of folding steel plates and concrete, without a headed stud. The folding steel plate was assembled by a high strength bolt instead of welding. To improve the workability in a field construction, a hat-shaped cap was attached to the junction with a slab. Monotonic load testing under two points was conducted under displacement control mode to analyze the flexural strength of the SPC beam using a cap as the shear connector. Five specimens with shear connector types, protrusion length, and different thickness of steel plates were constructed and tested. The experimental results were analyzed through the relationship between the shear strength ratio and flexural strength in KBC 2009. The test results showed a shear strength ratio of more than 40 %. In the case of using a cap-like specimen as the shear connector, the flexural strength was 70% of the value calculated as a fully composite beam. In addition, the cap showed a smaller shear strength than the stud, but the cap served as a shear connection. When the thickness of the steel plate was taken as a variable, the steel plate exhibited a bending strength of approximately 70% compared to a fully formed steel plate, and exhibited similar deformation performance. Local buckling occurred due to incomplete composite behavior, but local buckling occurred at a 5% higher strength for a relatively thick steel plate. The buckling width also decreased by 15%.