• 제목/요약/키워드: Dry pressing

검색결과 61건 처리시간 0.02초

Job Hazard Analyses for Musculoskeletal Disorder Risk Factors in Pressing Operations of Dry-cleaning Establishments

  • Park, Jung-Keun
    • Safety and Health at Work
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    • 제7권4호
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    • pp.389-393
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    • 2016
  • Job hazard analyses were conducted to assess exposure to musculoskeletal disorder (MSD) risk factors in seven workers of three dry-cleaning establishments. In accordance with the Washington State Ergonomics Rule, the analyses were performed in two separate steps: (1) observation and checklist approaches were made to identify a "caution zone job" in the seven workers' pressing operations across the three shops; and (2) detailed posture and motion analyses were undertaken to determine a "MSD hazard" in one worker's operation using a video technique. One "caution zone job" was identified and it was the pressing operation job in which five physical risk factors were found in the pressing operations. The detailed analyses confirmed that one "MSD hazard", i.e., awkward posture in shoulders, was prevalent in the pressing operations of the three dry-cleaning facilities. It would be desirable to reduce MSD risk factors including awkward shoulder posture in the dry-cleaning industry.

건식초지기술의 가능성 평가를 위한 건식초지기 개발 (Development of Dry Forming Mold for the Feasibility Study of Dry Forming of Paper)

  • 김종민;윤혜정;이학래
    • 펄프종이기술
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    • 제39권2호
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    • pp.1-8
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    • 2007
  • To examine the feasibility of dry forming technology for papermaking, a dry forming mold (DFM) was developed and evaluated. Main fanning section of DFM was a cylindrical tube, and at the top of the mold a stirring equipment was placed to disperse dry fibers. These fibers were screened using a hole type screen plate placed just under the stirring equipment and dropped freely on the fanning wire located 0.9 m below of the screen plate to form a dry fiber pad. The vertical and horizontal velocity of air flow in the forming cylinder were evaluated and analyzed to find the most effective method of air flow control in the cylinder. Humidification and pressing conditions to obtain a decent dry fanned papers were examined. Results showed dry fanned papers can be prepared with this dry forming mold. And this mold can be used to examine the effect of the papermaking process factors including pressing pressure, drying temperature, humidification on sheet quality of dry formed papers.

원주형 건식초지기를 이용한 건식초지 가능성 평가 (Feasibility Study of Dry Forming with Dry Forming Mould)

  • 김종민;이학래
    • 펄프종이기술
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    • 제41권1호
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    • pp.9-16
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    • 2009
  • Cylindrical dry forming mould was developed to carry out a feasibility study of dry forming of papers. The effect of disintegration, forming, humidification and pressing on dry formed papers was examined. Dry disintegrated fibers showed the similar fiber length distribution to wet disintegrated fibers, but they showed distorsion and damaged appearance on the surface. Process parameters required to form a uniform fiber pad was investigated. A proper screening and air dispersion method was selected that gives proper formation. Humidification and pressing conditions were examined to get a good dry formed papers in dry forming. Results showed that dry forming method can be used to make a sheets with reasonable formation and properties.

요소수지접착제(尿素樹脂接着劑)를 사용(使用)한 곰솔 집성재(集成材)의 제조조건(製造條件)이 접착성질(接着性質)에 미치는 영향(影響) (Influence of Adhesion Condition on the Laminated Wood of Pinus thunbergii glued with Urea-formaldhyde Resin)

  • 정인오;소원택;임기표
    • Journal of the Korean Wood Science and Technology
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    • 제12권2호
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    • pp.35-43
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    • 1984
  • This study was carried out to investigate the block shear strength of the 2ply laminated wood composed of Pinus thunbergii with ureaformaldehyde resin as adhesives according to pressure (6, 9, 12, 15kg/$cm^2$), pressing time(5, 10, 20, 30 hrs.), amount of spread(54, 108, 217, 324g/$cm^2$), hardener(10, 20, 30, 40% of 10% $NH_4CL$ on resin) and extender(0, 5, 10, 15% wheat flour on resin), and the bending strength and bending young's modulus of laminated beam according to the number of ply. The results were summarized as follows; 1. According to pressing pressure with amount of spread 217g/$cm^2$ both dry and wet shear strength of laminated wood showed the highest in 15kg/$cm^2$, and hot-cold soaking treatment showed the highest in 9kg/$cm^2$, while all shear strength of dry, wet and hot-cold soaked laminated wood have been reduced with the increasing of pressing time. 2. According to amount of spread, adhesion strength with the dry, wet and hot-cold soaking treatments revealed the highest in 217g/$cm^2$ and have been reduced under or over 217g/$cm^2$ of spread. 3. According to addition of hardener and extender, all shear strength of laminated block with the dry, wet and hot-cold soaking treatments have been reduced in increasing of addition amount of hardener and extender. The bending strength of beam according to the number of ply showed the highest in 2ply laminated wood and horizontal loading beam to glue line had the higher in strength than the vertical loading.

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Cordierite계 적외선 방사체의 열적 특성에 미치는 MnO$_2$의 영향 (Effects of MnO$_2$additives on the thermal properties of infrared radiator of Cordierite system)

  • 송창열;강이국;최두선;신용덕
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1994년도 춘계학술대회 논문집
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    • pp.133-137
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    • 1994
  • Infrared radiator of Cordierite system were manufactured using Cordierite(2Mgo$.$2Al$_2$O$_3$$.$5SiO$_2$) and Clay 30wt% as main materials and addition of MnO$_2$ from 0. 1 to 2 5wt% of Dry pressing and slip casting The effects of MnO$_2$ additives on the thermal properties of infrared radiator of Cordierite system. The more the thermal expansion could be lowered the more the amount (wt%) of additives MnO$_2$is increased in the below 4.5$\mu\textrm{m}$. The high efficiency Infrared radiator of Cordierite system using dry pressing method when the amount of additives MnO$_2$is 2.0 wt%

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관수방법별 압착정도에 따른 콩나물의 생장과 형태 변화 (Growth and Shape of Soybean Sprouts as Affected by Culture Method and Their Pressing)

  • 전승호;이창우;김홍영;전병삼;강진호
    • 한국자원식물학회지
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    • 제20권2호
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    • pp.145-149
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    • 2007
  • 콩나물의 형태는 상품성에 커다란 영향을 미친다. 본 연구는 상면살수 방식과 하면담수 방식에서 압착이 콩나물의 생장과 형태에 미치는 영향을 조사하고자 상면살수 방식에서는 상하로 재배통을 포개어 이를 매일 교환하거나, 계속 압착하는 방법과 하면담수 방식에서는 4일부터 압착을 가하거나 계속 압착하는 방법으로 처리를 가하여 시험을 수행하였던 바 그 결과를 요약하면 다음과 같다. 1. 개체당 형성된 세근수는 상면살수 및 하면담수 방식 모두 압착 강도가 강할수록 적었다. 2. 상면살수 방식에서 하배축은 계속 압착시 가장 짧았던 반면, 뿌리는 압착하지 않거나 계속 압착시 가장 길었다. 하면담수 방식에서는 하배축 길이에서만 무압착에서 가장 길고 계속 압착시 가장 짧았다. 3. 관수방식에 관계없이 자엽 바로 아래의 hook 직경은 압착 처리간 차이가 없었던 반면, 하배축 중간부분의 직경은 압착강도가 강할수록 굵어지는 경향을 보였다. 4. 생산수율과 관련된 개체당 전체생체중은 상면살수 방식에서는 무압착시 가장 적었으며, 압착 강도가 강할수록 증가하여 계속 압착시 가장 많았다. 그러나 하면담수 방식에서 전체생체 중은 압착처리간 차이가 없었다.

Development and Analysis of Dry Forming System for Innovation of Papermaking Technology

  • Kim, Jong-Min;Lee, Hak-Lae;Youn, Hye-Jung;Hwang, Min-Gu
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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    • pp.181-190
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    • 2006
  • This study was conducted to develop dry forming technology and evaluate the properties of dry formed paper made from Hw-BKP. A dry forming mold (DFM) was developed to observe the phenomena of dry forming and evaluate the properties of formed papers. To upgrade the DFM a dry forming system (DFS) was developed. This DFS was designed to improve the formation of dry formed papers and enhance the productivity of dry forming. Dry forming gave papers with greater bulk and opacity than wet forming. Tensile strength of dry formed paper was greater than that of conventional wet formed handsheet when they were made from the same dry disintegrated fibers. But tensile strength of conventional wet formed handsheet made from beaten fiber was much greater than that of dry formed paper made from dry disintegrated fibers. When solvent dried beaten fibers were used in dry forming, the tensile strength of dry formed papers reached 73.5% of the wet formed handsheets made from beaten fiber. It showed that dry forming has a significant potential in improving strength properties when proper preparation of fibers and appropriate humidification, pressing, and drying processes are employed.

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성형미세구조가 질화알루미늄의 소결 및 물성에 미치는 영향 (Effect of Green Microstructure on the Sintering and Properties of Aluminum Nitride)

  • 이해원;전형우;송휴섭
    • 한국세라믹학회지
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    • 제32권2호
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    • pp.209-216
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    • 1995
  • In order to investigate the effect o green microstructure on the sintering behavior and properties of AlN ceramics, samples were prepared by slip casting and dry pressing. The slip cast samples had high green density, fine pore size and narrow pore size distribution. They showed much higher sinterability and more homogeneous sintered microstructure compared to the dry pressed samples. Both increased thermal conductivity and flexural strength for samples prepared by slip casting could be attributed to the improved microstructural homogeneity with isolated second phase(s).

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