• 펄프종이기술
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• 제46권6호
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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.

• 생명과학회지
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• 제13권4호
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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.

• 한국식품영양학회지
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• 제16권2호
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• pp.138-145
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• 2003

난백, bpp, gelatin 및 gluten을 농도별로 첨가하였을 때 페루산과 포클랜드산 오징어 모두에서 각각 4%, 5%, 3% 및 4% 첨가구가 가장 높은 jelly강도를 나타내었고, 그 이상의 첨가에서는 큰 변화가 없었다. 이때의 물성 특성 값들을 보면 절곡시험 값은 모두 B를 나타내어 두겹으로 접어 1/2정도만 균열이 생겼으며, 페루산 오징어 연제품의 경우 수분함량은 72.06~73.78%, 보수력은 88.53~91.11%사이였고, 포클랜드산 오징어 연제품의 경우 수분함량은 71.91~72.89%, 보수력은 90.21~93.25%사이였다. 그리고 가장 높은 jelly강도 값을 나타낸 경우는 bpp를 5% 첨가하였을 때이며 이때 페루산과 포클랜드산 오징어 연제품에서 각각 872$\pm$29g.cm와 982$\pm$26g.cm를 나타내었다. Gluten 4% 첨가의 경우 jelly강도의 증가폭에 비하여 탄력성과 깨짐성의 힘이 크게 나타났으며 보수력도 크게 증가되는데 반해 경도의 변화는 크지 않았으며, 이때의 절곡시험 값은 B, 수분함량은 페루산이 73.74%, 포클랜드 산이 72.89%로 나타났다. 이상의 결과에서 오징어를 이용한 연제품제조시 적절한 단백질류 첨가는 제품의 품질 향상에 효과가 있는 것으로 나타났다.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2002년도 춘계학술발표대회 논문집
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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.

• 소성∙가공
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• 제17권6호
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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.

• 펄프종이기술
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• 제45권5호
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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.

• 펄프종이기술
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• 제44권1호
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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.

• 한국철도학회논문집
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• 제17권2호
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• pp.87-93
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• 2014

국내에서 운행중인 프랑스 알스톰에서 도입된 고속철도차량인 KTX의 승강문 접이식 발판이 유럽 표준 규격인 EN14752를 따르고 있으나 접이식 스텝 동작 시 발판 형성 폭이 200mm가 되어 국내 20세에서 60세의 발평균 사이즈인 253mm에 미치지 못하고 있다. 신체구조 상 신체 하중은 발 뒤축에 대부분 걸리므로 현재의 발판은 승하차 시 전도나 미끄러짐이 발생 할 수 있는 위험이 존재하고 있으며, 실제 발생을 하고 있다. 이에 기존 차량 조건 내에서 발판의 폭을 확대하여 스텝 개념설계(안)의 구조해석을 수행하고 이의 안전성을 검토하였다.

• 펄프종이기술
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• 제42권3호
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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.

• 한국산학기술학회논문지
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• 제19권7호
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• pp.481-492
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• 2018

본 강판 콘크리트 합성보는 강판, 콘크리트 및 전단 연결재로 구성되어 2개의 이질 재료를 결합한다. 일반적으로 강판은 기존의 합성보에 용접하여 조립된다. 이 연구에서, SPC 보는 스터드가 없는 강판과 콘크리트로 구성된다. 절곡한 강판은 용접 대신 고강도 볼트로 조립된다. 현장 건설의 작업성을 향상시키기 위해 슬래브와 접합부에 모자 모양의 Cap이 부착되어있다. Cap을 전단연결재로 사용하여 SPC 보의 휨성능을 분석하기 위해 변위 제어 모드에서 단조 하중 2점가력 실험을 수행 하였다. 전단 연결재 유형, 돌출 길이, 강판의 두께의 변수를 갖는 5개의 시험편을 제작하여 시험 하였다. KBC 2009에서 제시하는 전단강도비와 휨강도비의 관계를 분석하였다. 시험 결과로 전단 강도비를 40% 이상으로 나타냈다. 전단 연결재와 Cap을 부착하였음에도 완전합성보로 가정한 휨강도의 70% 이상의 휨강도를 발휘하였다. 또한 Cap이 스터드 보다는 작은 전단강도를 보였으나, Cap이 전단연결재 역할을 하였다. 강판두께를 변수로 한 경우, 완전합성보 대비 약 70%의 휨강도를 발휘하였으며, 유사한 변형성능을 나타내었다. 불완전합성거동함에 따라 국부좌굴이 발생하였으나, 상대적으로 두꺼운 강판의 경우 5% 높은 강도에서 국부좌굴이 발생하였다. 또한 좌굴폭이 15% 감소하였다.