• 한국염색가공학회지
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• 제1권1호
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• pp.35-46
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• 1989

Experiments described in which cotton fabrics at different stages of chemical processing were abraded to different extents on a Stoll Abrasion Tester with three different abradants, namely, a worsted fabric, flax fabric and silicon carbide paper. The four different plain-weave cotton fabrics selected were 1) desized, 2) scoured and bleached, 3) mercerized, 4) resin-treated. The surface abrasive damages of treated fabrics were observed by SAM, and load-elongation percent retentions of abraded samples were measured by Instrong Tester. The result were as follows: 1. The maximum percent retention of load-elongation with three different abradants was exhibited by the scoured and bleached fabrics and the minimum by the resin finished fabric. 2. The electron micrographs of four different cotton fabrics abraded by flax, worsted fabric abradants for 900 rubs showed a large number of criss-crossing stray fibers in fabric structure. It may be the molecular adhesion for frictional resistance to be explained. 3. The electron micrographs of four different cotton fabrics abraded by silicone carbide abradants showed the form of busing or mashing fibers in fabric structure. The above might be on the basis of the ploughing theory.

• 수산해양기술연구
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• 제48권3호
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• pp.277-283
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• 2012

The characteristics of abrasive wear on sliding speed of glass fiber reinforcement (GF/PUR) composites were investigated at ambient temperature by pin-on-disc friction test. The cumulative wear volume, friction coefficient and surface roughness of these materials on sliding speed were determined experimentally. The major failure mechanisms were lapping layers, deformation of resin, ploughing, delamination, and cracking by scanning electric microscopy (SEM) photograph of the tested surface. As increasing the sliding speed the GF/PUR composites indicated higher friction coefficient. The surface roughness of the GF/PUR composites was increased as the sliding speed was higher in wear test.

• 수산해양기술연구
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• 제49권4호
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• pp.492-499
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• 2013

The characteristics of abrasive wear of the rubber matrix composites filled with nano sized silica particles were investigated at ambient temperature by pin-on-disc friction test. The range of volume fraction of silica particles tested are between 11% to 25%. The cumulative wear volume and friction coefficient of these materials on particle volume fraction were determined experimentally. The major failure mechanisms were lapping layers, deformation of matrix, ploughing, deboding of particles and microcracking by scanning electric microscopy photograph of the tested surface. The cumulative wear volume showed a tendency to increase nonlinear with increase of sliding distance. As increasing the silica particles of these composites indicated higher friction coefficient.

• Journal of Welding and Joining
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• 제19권5호
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• pp.540-547
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• 2001

This study has evaluated the wear behavior of PTA (Plasma Transferred Arc) Inconel 625 and Stellite 6 overlays on Nimonic 80A substrate. Nimonic 80A alloy was also included for comparison. In order to evaluate the wear performance, three-body abrasive wear test and pin-on-disk dry sliding wear test were performed. Microstructural development during the solidification of deposits is also discussed. Wear test results show that the wear rate of Stellite 6 deposit is lower than that of Inconel 625 deposit and Nimonic 80A. The sliding wear resistance of overlay deposits follows a similar trend to the abrasive wear resistance, but for Nimonic 80A. The main wear mechanisms were abrasive wear for Inconel 625 deposit, adhesive wear and delamination for Stellite 6 deposit in pin-on-disk dry sliding wear test and ploughing in three-body abrasive wear test. Cross sectional examinations of the worn surface of pin specimens after pin-on-disk dry sliding wear test implies that the plastic deformation near worn surface has occurred during the wear testing.

• 수산해양기술연구
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• 제46권4호
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• pp.495-502
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• 2010

The effect of load and sliding speed on abrasive wear characteristics of glass fiber/polyurethane (GF/PUR) composites were investigated at ambient temperature by pin-on-disc friction test. The friction coefficient, cumulative wear volume and surface roughness of these materials against SiC abrasive paper were determined experimentally. Experimental results showed that the surface roughness of the GF/PUR composites was increased as applied load was higher in wear test. The cumulative wear volume tended to increase nonlinearly with increase of sliding distance and depended on applied load and sliding speed for these composites. It could be verified by scanning electric microscopy (SEM) photograph of surface tested that major failure mechanisms were lapping layers, ploughing, delamination, deformation of resin and cracking.

• 한국표면공학회지
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• 제37권3호
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• pp.137-145
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• 2004

This study surveys the microscopic wear of CVD TiN coatings in repeated sliding, using the SEM Tribosystem as in-situ system. According to the research, the depth of wear groove and the specific wear amount are changed by the transition of the microscopic wear mode. This investigation leads to the fact that the change of wear characteristics produces the transition of the wear mode. In this survey, four modes are observed for CVD TiN coatings with the thickness of 1.6$\mu\textrm{m}$: ploughing, powder formation, flake formation and coating delimitation. The microscopic wear properties is quantitatively evaluated in terms with the microscopic wear mode and the specific wear amount. These relationships prove that the observation of wear modes with a SEM Tribosystem is useful to evaluate wear properties.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.663-664
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• 2006

Sintered Ti(C,N)-based cermets were treated with hot isostatic pressing (HIP) at different nitrogen pressures. The tribological properties of the treated cermets have been evaluated. The results show that a hard near-surface area rich in TiN formed after HIP treatment. The cermets treated at higher pressure had a relatively lower friction coefficient and specific wear rate. In all cases the microhardness of treated cermets is higher than that without HIP natridation. The wear mechanisms of cermets were hard particle flaking-off and ploughing. It was also found that the HIP natridation is well-suited for improving the tribological properties of cermets.

• Tribology and Lubricants
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• 제20권3호
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• pp.125-131
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• 2004

Nano-wear behavior of amorphous carbon films was studied by Atomic Force Microscopy. The a-C films are deposited on Si(100) substrate by DC magnetron sputtering method. The influences of different surface roughness on the nano-wear are investigated. Nano-wear tests were carried out using a very sharp diamond coated tip. Its spring constant was 1.6 N/m and radius of curvature was 110 nm. Normal force used in the wear tests ranged 0 to 400 nN. It was found that surface depression occurred during scratching because of plastic deformation and abrasive wear (cutting St ploughing). Wear depth increased linearly with normal force. Changing the surface roughness variables according to the bias pulse control, the less surface roughness decreased the wear depth. The thickness did not affect the wear resistance.

• 한국제4기학회지
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• 제14권1호
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• pp.33-48
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• 2000

한반도에서 구석기시대부터 고려시대까지의 자연식생 간섭사를 시공간적 관점에서 복원하였다. 자연식생 간섭은 신석기시대에 본격화되었으며, 간섭은 초기에 저지와 해안에서 이루어졌으나, 후기에는 내륙으로 확산되었다. 청동기시대에는 밭의 개간이 활발해지고, 특정 수종에 대한 선택적 이용에 따른 간섭이 있었다. 철기시대에는 밭농사를 위한 개간이 한반도 전역에서 이루어져 자연식생의 파괴가 계속되었다. 삼국시대에는 별채, 목재 가공, 철제 농기구 사용, 가축에 의한 땅 갈기 등이 도입되면서 경작지 확대를 위한 자연식생의 간섭이 계속되었다. 고려시대에는 개간이 장려되면서 다락밭이 조성되고, 땔감, 조선, 광업, 목판 인쇄, 개간 등으로 자연식생의 간섭이 심각해졌다. 자연식생 간섭을 가져온 주된 요인은 농경 및 벌채와 관련된 인간의 활동이었고, 그 외 일상생활과 산업에서도 산림 식생의 간섭은 발생했다. 신석기시대 전기의 괭이농사, 후기의 보습농사, 청동기시대의 가축에 의한 보습농사, 철기시대의 농기구를 이용한 농사와 삼림 벌채 등으로 농경에 의한 자연식생의 간섭이 지속적으로 이루어졌다. 고구려의 밭농사, 백제의 논농사와 밭농사, 신라의 밭농사, 통일신라 때 밭의 확대 개간, 고려 때 개간 장려에 따라 다락밭이 확산되면서 전국에서 산림 훼손 피해가 심하였다 벌채는 신석기시대 초기부터 본격화되어 후기에는 섬이나 내륙으로 확산되었다. 밭의 수요가 증가하면서 벌채는 계속되었고, 청동기시대와 철기시대에는 목공구가 발달하면서 자연식생의 제거가 쉬워졌다. 고구려의 밭농사, 백제의 앞선 목재 가공 기술, 신라와 가야의 광물 생산, 목재 가공, 개간에 따라 식생 파괴가 심했다. 고려 때에는 연료와 개간으로 나무가 벌채되었고, 대신 산에 소나무 등을 심으면서 마을 주변에서 소나무 숲 경관이 자연스레 형성되었다. 자연식생 간섭을 가져온 기타 활동으로는 구석기 전기의 석기와 불, 신석기시대의 정착생활과 관련된 활동, 청동기시대의 제련, 철기시대 철제 생활용구 제작, 고조선의 온돌난방, 삼국시대의 아궁이·굴뚝을 갖춘 온돌방, 신라의 많은 숯 사용, 고려의 선박 건조, 전란, 목판 인쇄, 연료, 경제작물 재배, 전면적인 온돌난방 보급 등이 있다.

• 한국기후변화학회지
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• 제3권2호
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• pp.129-142
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• 2012

본 연구는 벼 생산에 필요한 농자재의 제조와 벼 재배과정 그리고 농자재의 폐기과정에서 발생되는 탄소성적을 산정하고, 주요한 온실가스인 메탄의 발생 저감을 위한 재배기술을 비교평가하기 위해 수행되었다. 벼 생산 단계에서 탄소 발생량은 투입된 농자재의 물량을 기준으로 농자재와 에너지의 제조단계에서 탄소발생량, 농작물 생육 단계에서는 시비질소 유래 아산화질소 발생량과 에너지 소비에 탄소 발생량, 농법에 따른 메탄발생량 그리고 농자재의 폐기에 따른 탄소발생량의 합으로 산정할 수 있다. 벼 1 kg 생산 단계에서 발생되는 이산화탄소는 1.40 kg이었으며, 발생된 온실가스 배출비율은 벼 생육 단계에서 메탄 유래 탄소발생량이 71.1%로 가장 많았고, 다음으로 시용된 질소에 의한 아산화질소 유래 탄소발생량이 11.8%였으며, 복합비료 제조단계에서 발생된 탄소발생량이 7.6%에 달하였다. 벼 재배기술 별 메탄 발생량을 비교한 결과, 중만생종 대비 조생종 품종재배로 44.4%, 늘 물대기 대비 중간 물떼기로 43.8%, 암거배수처리로 38.7%, 이앙재배 대비 직파재배로 32.0%, 경운 대비 무경운 재배로 20.9%의 감축 효과가 있는 것으로 나타났다. 향후 전과정 지구온난화 평가방법을 이용하여 온실가스 감축 실적의 측정-보고-검증 체계 구축이 필요하며, 이는 탄소배출권 거래제나 저탄소농산물 인증제의 과학적 근거를 제시하는 데 기여할 것이다.