• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.542-545
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• 1990

Texture provides an important source of information about the local orientation of visible surfaces. In this study the 3D shape of a textured surface is recovered from its perspective projection image on the assumption that the texture is homogeneously distributed. To recover 3D structure, the distorting effects of the perspective projection must be distinguished from properties of the texture. In this study, paraperspective projection, approximation of perspective projection, has employed.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2006년도 춘계학술발표회 논문집
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• pp.369-373
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• 2006

본 연구는 3차원 도시 모델링을 위해 라이브러리 기반의 texture mapping 기법을 사용하여 건물 모델을 제작하였다. 이 기법은 건물의 종류 및 특성에 따라 라이브러리 형태로 구축되어있는 texture map을 선택, 출력하여 3차원 건물 프레임에 mapping하는 과정으로 이루어진다. 이 기법의 효과적인 적용을 위해 LiDAR 데이터를 이용하여 건물을 자동적으로 분류하였고, LiDAR 데이터와 수치지도를 이용하여 단위 모델 구현을 위한 건물의 3차원 프레임을 제작하였다. 또한 사실감 있는 건물 texture를 구현하기 위해 실제 건물의 지상사진을 이용하여 texture map 라이브러리를 구축하였다.

• 한국정보과학회논문지:시스템및이론
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• 제31권10호
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• pp.603-609
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• 2004

절차적(procedural) 텍스쳐는 다양한 해상도로 텍스쳐 공간을 표현할 수 있으며, 매우 적은 저장 공간을 사용하는 장점을 가지고 있다. 그러나 절차적 표현을 위한 암시적(implicit) 방법을 이해하기 어렵고 프로그래밍에 익숙하지 않은 일반 사용자가 다루기 힘들다. 본 논문에서는 사용자의 직관적인 디자인작업을 통해 절차적 패턴을 자동으로 생성하는 인터랙티브 시스템이 제안된다. 전체 디자인 과정은 다중레이어(layer)를 기반으로 하며 데이타, 연산 및 출력 노드 등으로 구성된 그래프 구조로 표현된다. 제안된 시스템은 일반 사용자에게 유연한 인터페이스를 제공하여 프로그래밍 작업 없이 절차적 텍스쳐 쉐이더를 자동으로 생성하도록 한다. 시뮬레이션 결과로부터 제안된 방법이 다양한 패턴을 효과적으로 제작할 수 있음을 확인하였다.

• 한국분말재료학회지
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• 제10권2호
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• pp.103-107
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• 2003

Aluminum-based $Al/Al_2O_3$ composites were fabricated by a powder-in sheath rolling method. A stainless steel tube with outer diameter of 12 mm and wall thickness of 1 mm was used as a sheath. A mixture of aluminum powder and $Al_2O_3$ particles of which volume content was varied from 5 to 20%, was filled in the tube by tap filling and then rolled by 75% reduction in thickness at ambient temperature. The rolled specimen was then sintered at 56$0^{\circ}C$ for 0.5 h. The mixture of Al powders and $Al_2O_3$ particles was successfully consolidated by the sheath rolling. The $Al/Al_2O_3$ composite fabricated by the sheath rolling showed a recrystallized structure, while unreinforced Al powder compact fabricated by the same procedure showed a deformed structure. The unreinforced Al powder compact was characterized by a deformation (rolling) texture of which main component is {112}<111>, while the $Al/Al_2O_3$ composite showed a mixed texture oi deformation and recrystallization. The sintering resulted in recrystallization in Al powder compact and grain growth in the composite.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 제5회 압연심포지엄 신 시장 개척을 위한 압연기술
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• pp.11-18
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• 2004

Asymmetric rolling, in which the circumferential velocities of the upper and lower rolls are different, can give rise to intense plastic shear strains and in turn shear deformation textures through the sheet thickness. The ideal shear deformation texture of fcc metals can be approximated by the <111> // ND and $\{001\}<110>$ orientations, among which the former improves the deep drawability. The ideal shear deformation texture for bcc metals can be approximated by the Goss $\{110\}<001>\;and\;\{112\}<111>$ orientations, among which the former improves the magnetic permeability along the <100> directions and is the prime orientation in grain oriented silicon steels. The intense shear strains can result in the grain refinement and hence improve mechanical properties. Steel sheets, especially ferritic stainless steel sheets, and aluminum alloy sheets may exhibit an undesirable surface roughening known as ridging or roping, when elongated along RD and TD, respectively. The ridging or roping is caused by differently oriented colonies, which are resulted from the <100> oriented columnar structure in ingots or billets, especially for ferritic stainless steels, that is not easily destroyed by the conventional rolling. The breakdown of columnar structure and the grain refinement can be achieved by asymmetric rolling, resulting in a decrease in the ridging problem.

• 한국식품과학회지
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• 제27권1호
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• pp.105-111
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• 1995

밥의 식미가 다른 일반계와 통일계 쌀을 대상으로 아밀로펙틴과 그 베타-한계덱스트린의 분자구조적 특성을 조사하고 밥의 텍스쳐와의 관련성을 검토하였다. 쌀 전분의 아밀로펙틴 분자구조는, 아밀로펙틴과 베타-한계 덱스트린의 사슬분포로 보아, $\overline{DP}$ 12.4의 A 사슬, $\overline{DP}$ 20.6의 짧은 B 사슬, $\overline{DP}$ 26.3의 중간 B 사슬, $\overline{DP}$ 45의 긴 B 사슬과 $\overline{DP}$ 55 이상의 초장쇄로 이루어진 polymodal이었다. 아밀로펙틴의 초장쇄는 긴 직쇄를 가진 사슬로서 아밀로펙틴의 평균 사슬길이, 고유점도, 베타-아밀라아제 분해한도와 정의 상관을 보이나 요오드 복합체의 최대흡수파장과는 부의 상관을 보였다. 아밀로펙틴과 베타-한계 덱스트린의 분자구조적 성질은 일반계와 통일계 쌀 시료간 차이를 보였다. 아밀로펙틴의 A 사슬에 대한 B 사슬의 비율은 일반계가 통일계 보다 약간 높았으나 초장쇄의 분포 비율은 일반계가 통일계 보다 더 낮았다. 아밀로펙틴의 분자구조와 밥의 텍스쳐와의 관계에서, 고유점도, 베타-아밀라아제 분해한도와 사슬길이 그러고 초장쇄는 밥의 경도와 정의 상관을, 부착성과는 부의 상관을 보였다. 따라서 밥의 식감은 아밀로펙틴의 긴 사슬이 적고 짧은 사슬이 많이 분포할 수록, 밥의 경도가 낮고 부착성이 높았다. 이러한 결과는 아밀로펙틴의 분자구조가 밥의 텍스쳐와 밀접한 관계가 없음을 나타내고 있다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.744-746
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• 2003

A 3D modeling of urban area can be composed the terrain modeling that can express specific and shape of the terrain and the object modeling such as buildings, trees and facilities which are found in urban areas. Especially in a 3D modeling of building, it is very important to make a unit model by simplifying 3D structure and to take a texture mapping, which can help visualize surface information. In this study, the texture mapping technique, based on library for 3D urban modeling, was used for building modeling. This technique applies the texture map in the form of library which is constructed as building types, and then take mapping to the 3D building frame. For effectively apply, this technique, we classified buildings automatically using LiDAR data and made 3D frame using LiDAR and digital map. To express the realistic building texture, we made the texture library using real building photograph.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.323-323
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• 2010

Saw damage of crystalline silicon wafer is unavoidable factor. Usually, alkali treatment for removing the damage has been carried out as the saw damage removal (SDR) process for priming the alkali texture. It usually takes lots of time and energy to remove the sawed damages for solar grade crystalline silicon wafers We implemented two different mixed acidic solution treatments to obtain the improved surface structure of silicon wafer without much sacrifice of the silicon wafer thickness. At the first step, the silicon wafer was dipped into the mixed acidic solution of $HF:HNO_3$=1:2 ration for polished surface and at the second step, it was dipped into the diluted mixed acidic solution of $HF:HNO_3:H_2O$=7:3:10 ratio for porous structure. This double treatment to the silicon wafer brought lower reflectance (25% to 6%) and longer carrier lifetime ($0.15\;{\mu}s$ to $0.39\;{\mu}s$) comparing to the bare poly-crystalline silicon wafer. With optimizing the concentration ratio and the dilution ratio, we can not only effectively substitute the time consuming process of SDR to some extent but also skip plasma enhanced chemical vapor deposition (PECVD) process. Moreover, to conduct alkali texture for pyramidal structure on silicon wafer surface, we can use only nitric acid rich solution of the mixed acidic solution treatment instead of implementing SDR.

• 열처리공학회지
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• 제34권3호
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• pp.122-129
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• 2021

This study focuses on the microstructural development of 99% magnesium alloy sheet manufactured using twin roll casting (TRC) process. Herein, a plate with a thickness of 5 mm was manufactured using the TRC process, homogenization heat treatment was performed at 400℃ for 2-32 h, and finally, the change in microstructure was evaluated via optical microscopy and textural analysis. The results suggest that the plate manufactured using the TRC process was not destroyed and was successfully rolled into a plate. Microscopic observation suggested that the dendritic cast structure was arranged along the rolling direction. And the central layer of the rolled plate, where was present in a liquid state at the beginning of rolling, solidified later during the TRC process to form central segregation. The initial cast structure and inhomogeneous structure of the plate were recrystallized by homogenization heat treatment for only 2 h, and it was confirmed that the segregated part of the central layer became homogeneous and recrystallization occurred. Grain growth occurred as the heat treatment time increased, and secondary recrystallization occurred, wherein only some grains were grown. The textural analysis, which was conducted via X-ray diffraction, confirmed that the relatively weak basal plane texture developed using the TRC process was formed into a random texture after heat treatment.

• 한국CDE학회논문집
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• 제4권1호
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• pp.1-11
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• 1999

surface texture denotes set of tiny repetitive geometric features on an object surface. 3D Printing can readily create a surface of controlled macro-textures of high geometric complexity. Designing surface textures for 3D Printing, however, is difficult due to complex macro-structure of the tiny texture geometry since it needs to be compatible with the non-traditioal manufacturing method. In this paper we propose a visual simulation technique involving development of a virtual model-an intermediate geometric model-of the surface texture design prior to fabricating the physical model. Careful examination of the virtual model before the actual fabrication can help minimize unwanted design iterations. The proposed technique demonstrated visualization capability by comparing the virtual model with the physical model for several test cases.