• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.413-416
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• 2006

Two clad composites of five ply sheets comprising STS430/AA3003/AA3003/AA3003/STS430 and STS430/AA3003/STS430/AA3003/STS430 were produced by roll cladding at $350^{\circ}C$. In order to clarify the deformation behavior and strain states in the composites during roll cladding, the variation of individual sheet thickness and the evolution of through thickness textures and microstructures of the composites were investigated. The thickness reduction of each sheet depended on the location of the sheet and on the strength of each sheet in the composites. In order to elucidate the evolution of textures and microstructures in AA3003 sheets, the strain states in AA3003 sheets during roll cladding were calculated by FEM. The formation of shear textures and fine grains in AA3003 sheet was discussed in terms of the strain states in each sheet layer. Finally, the strain states extracted from the FEM were verified by texture simulations

• 한국의류학회지
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• 제32권5호
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• pp.800-807
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• 2008

The purpose of this study is to compare the subjective texture of actual objects and their picture images on the Internet to find out a method to present visual images in order to supply information similar real objects. For this study, seven knit fabrics and four presentation methods of visual images including twice magnifications and two dimensions of 2D and 3D. The results of this study were as follows: There are significant differences among subjective textures evaluated by touching seven fabrics actually and we can verify the effects of fiber contents and loop length of knit on textures. We can find out differences of texture depending on presentation methods. In case of 2D evaluation of knits fabrics, visual images of real size present a little exact information on roughness and heaviness whereas those of twice magnification do roughness, wetness, softness and luster. And 3D images give us more exact information of textures on softness, heaviness and warmness, but rather twice enlarged 3D image can't supply an information of heaviness texture.

• Fibers and Polymers
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• 제7권2호
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• pp.203-212
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• 2006

The purpose of this study was to examine the effects of the structural properties of plain knit fabrics on the subjective perception of textures, sensibilities, and preference among consumers. This study, then, aimed to provide useful information with respect to planning and designing knitted fabrics by predicting the subjective characteristics analyzed according to their structural properties. For this purpose, we employed statistical analysis tools, such as factor and regression analysis and an adaptive-network-based fuzzy inference system(ANFIS), thereby combining the merits of fuzzy and neural networks and presupposing a non-linear relationship. Through factor analysis, we also categorized the subjective textures into 'roughness', 'softness', 'bulkiness' and 'stretch-ability' with R2=70.32%: and categorized the sensibilities into 'Stable/Neat', 'Natural/Comfortable' and 'Feminine/Elegant' with R2=68.12%. We analyzed subjective textures, sensibilities, and preference with ANFIS, assuming non-linear relationships; consequently, we were able to generate three or four fuzzy rules using wool/rayon fiber content and loop length as input data. The textures of roughness and softness exhibited a linear relationship, but other subjective characteristics demonstrated a non-linear input-output relationship. Compared with linear regression analysis, the ANFIS exhibited had higher predictive power with respect to predicting subjective characteristics.

• 자원환경지질
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• 제14권1호
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• pp.27-33
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• 1981

Blake Plateau 상(上)의 망간단괴(團塊)는 주(主)로 미정질(微晶質) 내지(乃至) 은미정질(隱微晶質) 토도로카이트와 소량(少量)의 석영(石英), 점토(粘土), 탄산염광물(炭酸鹽鑛物) 및 필 립사이트로 구성(構成)되어 있다. 망간단괴(團塊)는 그 단면(斷面)에서 동심엔층상(同心円層狀), 내핵(內核), 부정합(不整合), 열극충전(裂隙充塡) 등(等)의 육안적(肉眼的) 구조(構造)를 가지고 있고 현미경하(顯微鏡下)에서는 교질상(膠質狀), 비편상(碑片狀) 및 다이아제네시스 구조(構造)가 관찰(觀察)된다. 어떤 기원(起源)의 단괴(團塊)의 조직(組織)에 대(對)하여도 적용(適用)될 수 있는 새로운 교질상(膠質狀) 조직분류(組織分類) 방안(方案)을 발견(發見)하여 체계화(體系化)하였다. 즉(卽) 호상조직(縞狀組織), 혹모양조직(組織) 및 구상조직(球狀組織)의 교질상물질(膠質狀物質)의 3가지 기본(基本) 조직단위(組織單位)가 존재(存在)한다는 것이 밝혀졌으며, 이의 체계적(體系的)인 세분(細分)으로 모든 망간단괴(團塊)의 조직(組織)의 체계적(體系的)인 기술(記述)과 연구(硏究)가 가능(可能)하게 되었다. 3가지 기본(基本) 조직단위(組織單位)의 존재(存在)는 망간 단괴성장(團塊成長)에 있어서 적어도 3가지 주성장방식(主成長方式)이 존재(存在)한다는 것을 지시(指示)해준다.

• 한국재료학회지
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• 제23권2호
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• pp.116-122
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• 2013

For fabricating silicon solar cells with high conversion efficiency, texturing is one of the most effective techniques to increase short circuit current by enhancing light trapping. In this study, four different types of textures, large V-groove, large U-groove, small V-groove, and small U-groove, were prepared by a wet etching process. Silicon substrates with V-grooves were fabricated by an anisotropic etching process using a KOH solution mixed with isopropyl alcohol (IPA), and the size of the V-grooves was controlled by varying the concentration of IPA. The isotropic etching process following anisotropic etching resulted in U-grooves and the isotropic etching time was determined to obtain U-grooves with an opening angle of approximately $60^{\circ}$. The results indicated that U-grooves had a larger diffuse reflectance than V-grooves and the reflectances of small grooves was slightly higher than those of large grooves depending on the size of the grooves. Then amorphous Si:H thin film solar cells were fabricated on textured substrates to investigate the light trapping effect of textures with different shapes and sizes. Among the textures fabricated in this work, the solar cells on the substrate with small U-grooves had the largest short circuit current, 19.20 mA/$cm^2$. External quantum efficiency data also demonstrated that the small, U-shape textures are more effective for light trapping than large, V-shape textures.

• 한국지구과학회지
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• 제29권3호
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• pp.305-314
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• 2008

이 연구는 7차 고등학교 지구과학 II 교과서의 내용 중 화성암의 조직 개념에 대한 본문 진술을 분석하고 문제점을 지적하고 그 개선 방안을 모색하였다. 과학 교과서의 개념 진술이 정확하지 않아 학습자들에게 오개념을 유발하거나 재강화할 가능성이 있는 여러 진술문이 발견되었다. 화산암에 대하여 세립질, 유리질 또는 반상 조직을 기술하고 있으며, 심성암에 대하여 완정질, 입상, 조립질 및 등립질 조직 등 다양한 조직을 제시하고 있다. 이들은 화성암 조직 분류체계 기준의 혼란에 관련된 것들이었다. 화성암의 조직에 대한 정확한 개념을 전달하기 위한 화성암 분류 기준의 개선방안들을 제시하였다. 화성암을 구성광물의 입도, 상대적인 크기와 결정도에 따라 화산암에는 비현정질 또는 반상 조직을, 심성암에는 현정질 또는 완정질, 등립상 조직을 사용하여야 한다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.1173-1176
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• 2005

Depending on the characteristics of each 3D-DCT block, images can be classified into three types: images with motion and textures, images with high textures and little motion, images with little textures and little motion. In this paper, we propose an adaptive watermarking method using these characteristics of each 3D-DCT block. and the human visual system. The proposed method classifies patterns of 3D-DCT blocks based on the motion and texture information, and classifies the image type according to the ratio of these patterns. The watermark is inserted proportional to the 3D-DCT coefficients by using pattern adaptive JND, which. makes the proposed watermarking robust by inserting watermarks in as many blocks as possible. Experimental results show that the proposed method achieves better performance in terms of invisibility and robustness than the previous method.

• 소성∙가공
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• 제7권5호
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• pp.459-464
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• 1998

Effect of the several initial textures such as random texture, rolling texture and cube texture, on the plane strain stretching was studied by interpretation of the finite element method. The calculation of yield locus indicated that the sheet oriented in the cube texture exhibits easy yielding on uniaxial stress state whereas the sheet having either a random or the rolling texture exhibits easy yielding on shear deformation. Upon stretching tests, the thickness strain at the center region contacting the punch was identical regardless of the initial textures while the dependence of the thickness strain on the initial texture was found in the other regions. In general punch loads required or the sheet with an initial cube texture was as expected from calculated yield locus, lower than those for the others.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 추계학술대회논문집
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• pp.138-139
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• 2003

Sandwich sheet samples comprising AA1050/AA1050/AA1050, AA3003/AA1050/AA3003, AA3003 AA3003 AA3003. AA1050/AA3003/AA1050, SUS430/AA3003/SUS430, AA3003/SUS430/AA3003 and SUS430/SUS430/SUS430 were cold rolled in order to clarify the evolution of strain states md textures in the sandwich samples. To investigate the effect of stacking sequences of the samples on strain and texture, the relative contribution of each layer to the total reduction was measured and textures of the mid-layer sheet of sandwich samples were determined.

• 소성∙가공
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• 제15권7호
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• pp.479-484
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• 2006

The evolution of strain states and textures during rolling with various conditions was investigated by finite element method (FEM) simulations and measurements of rolling textures. Symmetrical rolling with a high friction gives rise to a strong variation of shear strains in rolled sample leading to the formation of texture gradients throughout the thickness layers. A small variation of shear strains during rolling with a well lubrication condition leads to the formation of a fairly homogeneous rolling texture throughout the sheet thickness. During asymmetrical rolling, a proper control of rolling parameters provides the evolution of a fairly homogeneous shear texture throughout the whole sheet thickness.