• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 춘계학술대회논문집
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• pp.105-108
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• 2003

Sheets of aluminum alloy 1100 were asymmetrically cold rolled in a rolling mill with different roll speeds. In order to promote the shear deformation during asymmetrical rolling, cold rolling without lubrication was performed. The evolution of texture components during asymmetrical rolling was investigated by the calculation of the orientation distribution function (ODF) using the monoclinic sample symmetry. The strain state during asymmetrical rolling was tackled by means of FEM calculations. Asymmetrical rolling gave rise to the development of pronounced strain gradients throughout the thickness layers which resulted in the formation of strong texture gradients in the aluminum sheet.

• 소성∙가공
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• 제12권3호
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• pp.244-250
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• 2003

Sheets of aluminum alloy 1100 were asymmetrically cold rolled in a rolling mill with different roll speeds. In order to promote the shear deformation during asymmetrical rolling, cold rolling without lubrication was performed with a roll speed ratio of 1.5/l.0. The evolution of texture components during asymmetrical rolling was investigated by the calculation of the orientation distribution function (ODF) using the monoclinic sample symmetry. The strain state during asymmetrical rolling was tackled by means of FEM calculations. Asymmetrical rolling gave rise to the development of pronounced strain gradients throughout the thickness layers which resulted in the formation of strong texture gradients in the aluminum sheet.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 제3회 압연심포지엄 논문집 압연기술의 미래개척 (Exploitation of Future Rolling Technologies)
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• pp.349-355
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• 1999

The texture inhomogeniety during rolling is one of the greatest problems. Especially, shear texture develops more easily during ferritic rolling of steel sheets at high temperatures due to friction between rolls and the material. In this study, the influence of front and back tensions on the texture development during ferritic rolling has been studied. The rolling textures were simulated using the full constrains Taylor-Bishiop-Hill model with the strain history obtained from finite element analysis. The calculated textures showed that the back tension rolling could reduce the shear component more effectively than front tension or rolling without tension. However, the experimental results showed that the lension effect was very small compared to our prediction. It might be attributed to initial texture and difference in frictions between simulation and experiments.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 추계학술대회 논문집
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• pp.309-312
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• 2001

FEM simulating system of the cross-rolling texture formation offers a systematic and efficient way of exploring the relationship between the process variables and the state of plastic anisotropy of sheet product. Cross-rolled sheets possess higher average plastic strain ratios and lower planer anisotropy than those of the straight-rolled sheets. The employed model is a finite-element polycrystal model which each element used in FEM is assumed to be a crystal having different orientation by Takahashi. Texture development, deformation textures due to cross-rolling are predicted for face-centered cubic sheet metal. Crystal orientations are assigned on the basis of the pole figures obtained by X-ray diffraction. Development of anisotropy during cross rolling of an fcc sheet material is predicted theoretically with respected to flow stress and R-value in tensile test.

• 한국작물학회지
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• 제61권1호
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• pp.1-8
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• 2016

본 연구는 국내 주요 벼 품종들 중 일부 품종들에 대하여 현미와 발아현미에 대한 아밀로펙틴 중합도와 식감관련 특성에 대해 비교 분석하였다. 아밀로펙틴은 단쇄비율이 높고 장쇄비율이 낮은 품종이 밥맛이 우수한 특성을 나태는 것으로 알려져 있는데 본 연구결과 발아현미가 일반현미에 비해 유의적으로 높아지는 결과를 나타냈다. 특히 하이아미와 진보가 다른 품종들에 비하여 유의적으로 단쇄비율이 높고 장쇄비율이 낮은 것으로 나타났다. 식감측정결과 진보의 경우 현미의 경도(hardness)와 탄력성(toughness)이 각각 84.6과 51.8에서 발아과정을 통해서 50.2와 30.2로 감소하였으며 찰기(stickiness)와 부착성(adhesiveness)은 발아현미밥의 60.6와 42.9에 비하여 현미밥에서 27.8과 30.8로 나타나 발아현미밥에서 찰기와 부착성이 각각 2.18, 1.39배 높은 값을 나타내었다. 또한 식감과 아밀로펙틴 중합도 특성과의 관계를 알아보기 위하여 경도, 탄력성, 찰기, 부착성과 아밀로펙틴 중합도 특성과의 상관관계를 분석하였는데, 발아현미에서 단쇄비율이 많을수록 경도와 탄력성이 감소되고 장쇄 비율이 높을수록 경도와 탄력성, 부착성이 증가하는 경향이 나타났다. 따라서 본 연구에서는 주요 벼 품종들의 현미에 대하여 발아 전과 후의 아밀로펙틴 중합도와 식감관련 특성을 종합적으로 비교 분석한 결과 발아과정에서 현미의 조직변화가 나타나고 발아 후 식감이 부드러워지고 찰기가 증대되어 밥맛이 향상된 것을 입증할 수 있었다. 또한 식감과 아밀로펙틴 중합도 특성과의 관계는 발아현미에서 뚜렷한 경향을 나타냈으며, 본 연구가 아밀로펙틴의 길이와 식감의 상관관계를 밝히기 위한 기초자료가 될 수 있을 것으로 사료된다.

• 열처리공학회지
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• 제32권6호
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• pp.256-262
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• 2019

The microstructural features and texture development by both hot rolling and hot forging in ${\gamma}-TiAl$ alloy were investigated. In addition, additional heat treatment after hot forging was conducted to recognize change of the microstructure and texture evolution. The obtained microstructural features through dynamic recrystallization after hot deformed ${\gamma}-TiAl$ were quite different because two kinds of formation process were occurred depending on deformation condition. However, analyzed texture tends to be random orientation due to intermediate annealing up to ${\alpha}+{\beta}$ region during the hot deformation process. After additional heat treatment, microstructure transformed into fully lamellar microstructure and randomly oriented texture was also observed due to the same reason as before. Tensile test at room temperature demonstrated that anisotropy of mechanical properties were not appeared and transgranular fracture was occurred between interface of ${\alpha}_2/{\gamma}$. As a result, it could be suggested that microstructural features influenced much more than texture development on mechanical properties at room temperature.

• 패션비즈니스
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• 제13권6호
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• pp.89-98
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• 2009

Computer development and new printing technology allow us to express a new type of digital textile designs those were not possible in the past. In this study, watercolor overlaying effect of various colors was tried using airbrush tool in Photoshop program. Photoshop program is a powerful graphic tool and can be used in textile design area to generate various types of designs. Woven texture was also applied to the design to give yarn dyed effects or rich appearance. Photoshop program was also used to develop woven texture without the help of the professional textile CAD. Photoshop channels enables the designers to apply various textures to the image. Plain weave and houndstooth were applied in this study. Colorways of the developed designs having watercolor effect and woven texture by applying Photoshop color adjustment function. Quick and simultaneous changes of colors were possible using this method. The developed textile designs were printed by transfer DTP. Successful textile design prints were expressed and showed watercolor overlaying effect and woven texture. The printed textiles show a little brighter color, and therefore, sample printing is recommendable in case of color sensitive production.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.222-225
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• 2006

The effect of lubrication on the development of textures and Microstructure was studied by different lubricating condition during hot rolling of AA1050 aluminum alloy. Hot rolling without lubrication led to the evolution of the pronounced through-thickness texture gradients, whereas hot rolling with lubrication gave rise to the formation of uniform rolling texture in the whole thickness layer. The variation of texture and microstructure according to hot rolling condition are investigated by X-ray diffractometer (XRD) and Electron Back-Scattered Diffraction (EBSD). The experimental results were discussed base on the finite element method (FEM) simulation. FEM calculation reveals that a larger friction between roll and sheet causes the deviated strain state from a plane strain leading to the formation of shear textures in the thickness layers close to the surface.

• 한국세라믹학회지
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• 제43권3호
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• pp.152-155
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• 2006

Silicon carbide ceramics seeded with 10-30 wt% SiC whiskers are fabricated by hot pressing and annealing. A quantitative texture analysis including calculation of the Orientation Distribution Function (ODF) is used for obtaining the degrees of preferred orientation of the fabricated samples. The microstructure and crystallographic texture are discussed with respect to the effect of ${\beta}-SiC$ whisker seeds on the resulting fracture toughness values. The SEM microstructures and the texture data reveal a correlation between texture and fracture toughness anisotropy.

• Applied Microscopy
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• 제32권3호
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• pp.185-193
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• 2002

Texture electron diffraction pattern을 이용한 결정구조 해석 이론은 러시아어로 씌여졌거나, 영문판 저서의 일부에 간단히 소개 되어있어 이해에 어려움이 있다. 이들의 이론은 벡터의 이론과 관련된 여러 관계식을 이용해서 설명될 수 있으며, 이로서 몇 개의 식에 포함된 오류를 수정하였다.