• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.134-137
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• 2008

The effects of residual stress and surface defects on the mechanical properties of the high carbon steel filament used for the automotive tire have been experimentally investigated. The samples were fabricated with annealing temperature. The residual stress was measured by focused ion beam and strain mapping software which has advantages, such as data with high accuracy and fast data acquisition time. Mechanical properties, such as tensile strength and fatigue resistance, were gradually increased up to $200^{\circ}C$ and then slightly decreased. From the measurement of residual stress and level of surface defect, it was revealed that the critical factor was varied with different temperature region. That is, the fatigue resistance increased due to decreasing the residual stress and decreased due to increasing the size and distribution of surface defect.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 추계학술대회 논문집
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• pp.213-216
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• 2009

In this study, three cold-rolled TRIP steels containing different Al content (0.04wt%, 1.0 wt.% and 2.00wt%) were fabricated to understand the complex effects of Al in TRIP steel. The influences of Al on microstructural evolution of cold-rolled TRIP steels have been analyzed by using advanced analysis techniques, such as transmission electron microscope (TEM) and three dimensional atom probe tomography (3D-APT). TEM results revealed that second phases such as bainte and retained austenite decrease with increase of Al content. In addition, 3D-APT was used to characterize atomic-scale distribution of alloying elements at the constituent phases. Through these analysis techniques, the advanced characteristics of constituent microstructure in TRIP steels were identified depending on Al contents in TRIP steels.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2008년도 제38차 학술발표대회
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• pp.150-152
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• 2008

사회가 발달하여 감성사회로 접어들면서, 섬유산업도 새로운 감성소재를 개발하기 위한 연구를 추구하고 있다. 이러한 분야의 연구수단으로 생체모방(Biomimetics)을 활용하는 연구개발이 활발히 진행되고 있는데, 이중 미래지향적인 차세대 섬유로 Morphotex(R)를 이용한 Morpho 직물이 있다. 감성소재분야에서 '구조발색섬유'라고 불리어지는 독특한 색미를 가진 섬유소재인 Morphotex$^{(R)}$는 남미의 MORPHO 나비 날개의 구조적 발색원리를 모방하여 만든 광발색섬유로 염료와 안료를 사용하지 않는 친환경섬유이면서 고기능성과 쾌적성을 겸비한 소재로 요즘 많은 각광을 받고 있다. 본 연구에서는 구조발색 소재를 이용하여 제직한 감성의류소재 직물의 감량조건에 따른 감성특성을 비교.분석해보았다. 먼저 구조발색 소재로 제직 된 직물의 감량공정특성에 따른 구조발색 소재 직물의 인장 인열 특성을 분석하였으며 또한 KES-FB system으로 구조발색 소재 직물의 역학특성을 측정하고 측정한 역학특성으로부터 감성태를 평가해 보았다.

• 소성∙가공
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• 제17권7호
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• pp.491-495
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• 2008

Incremental forming path to manufacture a thick concave steel plate using the line array roll set is designed. To find the optimum forming path, the forming processes are simulated by the finite element method. A general-purpose commercial software, MSC MARC is used. A modeling with 8-node hexahedral elastic-plastic solid is performed to predict accurate springback and the analysis process was composed of 18 passes. The proposed forming paths are verified through experiments carried out in the prototype line array roll set. It is found that the process can be successfully applied to the fabrication of the dual curvature ship hull plate.

• 복식문화연구
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• 제15권5호
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• pp.852-862
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• 2007

This study was to investigate the physical properties and the external characteristics of denim fabrics(100% cotton non-spun denim, 98% cotton/2% polyurethane spun denim) such as tensile strength, thickness and weight, flex stiffness, surface color and shrinkage. The results of the study were as follows. After examining the change of external characteristics of before and after washing finishing for denim fabrics, denim with bio washing had increased pliability compared to denim without washing finishing but the pliability of the denim did not increase according to the intensity or frequency of washing. The luminance change according to washing finishing was high in the order of bio stone bleach washing, bio stone washing, bio washing and denim without washing finishing and the surface color became brighter in accordance with the increase of intensity and frequency of washing finishing.

• 구강회복응용과학지
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• 제33권4호
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• pp.307-313
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• 2017

본 증례에서는 상악 완전 무치악 환자에서 CAD/CAM으로 가공 지르코니아 바와 PEKK 슬리브를 제작하여, 바 어태치먼트를 활용한 임플란트 지지형 피개의치로 수복하였다. 2년간의 정기적인 경과 관찰 결과 심미적, 기능적으로 만족할 만한 결과를 얻었기에 이를 보고하는 바이다.

• 한국기계가공학회지
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• 제3권2호
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• pp.3-9
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• 2004

The main objectives of this paper are to determine optimum cutting conditions using experimental design method to manufacture pedicle screws. Generally, titanium alloys are known as difficult-to cut materials. In the machining of titanium alloy, high cutting temperature and strong chemical affinity between the tool and the work material are generated because of Its low thermal conductivity and chemical reactivity. Such phenomenon cause increase of tool wear and deterioration of surface quality. Thus, in this paper, required experimental investigations are performed to evaluate the machinability of titanium materials With tungsten carbide tools Required simulation and experiments are performed, and the results are investigated.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 춘계학술대회 논문집
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• pp.239-244
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• 2002

This study shows how the change of helix angle for different helix angle end mill affects machining accuracy. It was verified that cutting forces are remarkably low when endmill has helix angle of different helix angle $25^{\circ}\;, \; 31^{\circ}\; , \; 37^{\circ}$and AE signals have less relationship with the chance of helix angle Moreover, as the number of rotations are increased, the AE signals are increased with the proportion to the number but cutting forces are inversely proportional to the rotation.

• 한국공작기계학회논문집
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• 제15권1호
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• pp.82-87
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• 2006

The cutting tests of aluminum alloy with heat treatmented various hardnesses after rheo-fonning were carried out using CNC milling machine. The surface roughness(Ra, Rmax) of cut surface and cutting forces are measured at various cutting conditions such as low spindle speed, feed speed and hardness. In the CNC end-milling, the surface roughness increases as feed speed increases and decreases as spindle speed increases. However, the bulit-up edge has occurred on in case of low hardness and low feed speed. In experimental conditions, as the hardness of aluminum alloy increases, the surface roughness(Ra, Rmax) decreases

• 한국염색가공학회지
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• 제6권4호
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• pp.92-99
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• 1994

혈액이 이물질과 접촉하면 응고하는 성질은 생명유지를 위해서는 단단히 중요한 일이나, 인공재료를 이용하여 질병을 치료하고자 할 때는 이러한 혈전형성은 장애요인으로 작용한다. 1960년대부터 최근까지 항혈전성을 가진 재료에 대한 연구가 활발히 전개되고 있는데 그 동향도 조금씩 변모하여가고 있고, 접근해가는 방식이 여러가지로 세분화되고 있다. 여러 논문과 총설, 혹은 서적을 참고로 하면 재료의 분류를 항혈전을 일으키는 메카니즘을 몇가지로 나누고 여기에 포함되는 것들을 열거하는 방식을 채택하고 있다. 한편, 의료에 직접적으로 관여하는 재료는 대부분이 섬유고분자재료가 차지하고 있으며 이분야의 관계자들의 의료에의 공헌도는 아주 높으며 의료 관계자로부터의 기대 또한 크다. 특히 혈액과 접촉하여 혈책적합성을 나타내는 재료또한 대부분이 섬유고분자재료가 차지하고 있기 때문에 섬유고분자재료의 입장에서 이들을 분류하고 각각의 항혈전성 메카니즘과 응용방식의 이해가 우선되어야 할 것이며, 이를 바탕으로 해야 좀더 진보된 형태의 항혈전성 섬유고분자재료의 발달이 가능하리라 본다. 따라서, 이 논문에서는 항혈전성을 나타내는 각각의 섬유고분자들을 그 중심으로 하여 항혈전성 재료를 소개하고자 한다.