• 한국생산제조학회지
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• 제4권3호
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• pp.48-57
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• 1995

The feasibility of generating controller surface topographies in single-point conventional turning operations is investigated. First, a mathematical model of the surface generation process was developed. Second, in order to control the texture of the machined surface, a micro-positioning stage and the associated command generation software were designed and built. Experimental examples have shown that surface texture can be precisely controlled and is in good agrement with the theoretical predictions.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1995년도 춘계학술대회 논문집
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• pp.24-33
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• 1995

The feasibility of generating controlled surface topographies in single-point conventional turning operations is investigated. First a mathematical model of the surface generation process was developed. Second in order to control the texture of the machined surface a micro-positioning stage and the associated command generation software were designed and built. Experimental examples have shown that surface texture can be precisely controlled and is in good agreement with the theoretical predictions.

• 한국기계가공학회지
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• 제16권2호
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• pp.63-68
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• 2017

Friction occurs when surfaces that are in contact move relatively between solid surfaces, fluid layers, and materials slide against one another. This friction force causes wear on the contact surface, generates unwanted heat and leads to performance degradation. Thus, much research has been performed to avoid friction reduction. Among these studies, a textured surface that has micro patterns on the surface has drawn attention for its ability to reduce friction. A mathematical model is developed in this study to examine friction reduction due to the texture of a surface. Numerical simulations are carried out with respect to various factors such as the shape aspect ratio and texture depth of a diamond-shaped texture in the hydrodynamic lubrication regime. As a result, a shape aspect ratio of 1 is best for friction reduction.

• Tribology and Lubricants
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• 제20권5호
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• pp.266-271
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• 2004

The aim of this paper is to investigate the effect of surface texturing on reduction friction and to understand the potential of friction reduction through micro-scale dimple to fabricate by photolithography on pin-on-disk test using flat-on-flat contact geometry. It was verify that the friction property with respect to the same pitch has been influence on the size of dimple under lubricated sliding contact. Also, we can recognize from Stribeck curve that the friction property has a connection with the size of dimple. It can explain a relationship between the friction coefficient and a dimensionless parameter for lubrication condition. The friction property has been an effect on the size of surface texture on reduction friction, not only because the density of dimple, but also because the ratio of diameter/pitch. This ratio of approximately 0.5 recommend under the tested friction condition. It suggested that the ratio of d/p is an important parameter for surface texture design.

• 한국생산제조학회지
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• 제23권2호
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• pp.118-126
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• 2014

In this paper, a new method is proposed for the five-degree-of-freedom precision alignment and stitching of three-dimensional surface-profile data sets. The control parameters for correcting thealignment error are calculated from the surface profile data for overlapped areas among the adjacent measuring areas by using the "least squares method" and "maximum lag position of cross correlation function." To ensure the alignment and stitching reliability, the relationships betweenthe alignment uncertainty, overlapped area, and signal-to-noise level of the measured profile data are investigated. Based on the results of this uncertainty analysis, an appropriate size is proposed for the overlapped area according to the specimen's surface texture and noise level.

• 한국컴퓨터그래픽스학회논문지
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• 제3권1호
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• pp.23-28
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• 1997

본 논문은 range map과 texture map이 포함된 range image를 삼각형 메쉬로 된 3차원 형상으로 복원하고, 이 삼각형 메쉬를 기하학적 축소 알고리즘을 적용하여 간략화하는 방법에 대하여 기술한다. 그리고 이 논문에는 복원된 3차원 모델에 texture mapping이 가능하고 간략한 정도를 사용자가 쉽게 결정할 수 있으며, 실시간 multiple level-of-detail에 적용 가능한 빠른 속도의 간략화 방법을 제시한다. 구현한 방법을 국보급 문화재를 스캐닝한 실험 데이터에 적용하여 그 유효성을 입증한다.

• 소성∙가공
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• 제9권2호
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• pp.193-202
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• 2000

The influence of rolling draughts on the formation of through-thickness textures in aluminum 5000X sheet was investigated by X-ray texture measurements and microstructure observations. In order to intensify the deformation inhomogeneities, cold rolling was performed without lubrication. Applying a large draught gave rise to the formation of the shear texture at the surface, whereas a normal plane strain testure formed at the surface after deformation with a small draught. The orientation density along the $\beta$-fiber orientations which developed in the center layer of the rolled specimen was also dependent on the strain gradients in a roll gap. Upon annealing, the deformed substructure of sample surfaces was transformed into a fine grained recrystallized microsturcture through extended recovery reaction. However, coarse grains developed after the discontinuous recrystallization which gave rise to the development of the Cube-texture.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 춘계학술대회논문집
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• pp.184-187
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• 1999

The texture of electrodeposits is related to microstructure surface morphology and mechanical properties. When the electrodeposits annealed the recrystallization texture many be different from the original deposition texture. the <100> and <110> textures of nickel electrodeposits changed to the <100> and <{{{{ SQRT {310 } }}}}> textures when recrystallized The <100> and <{{{{ SQRT {310 } }}}}> mixed texture is changed to the <100> texture. The <002> texture of Zn electrodeposits didn't changed even after recrystallization.

• 한국융합학회논문지
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• 제7권6호
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• pp.193-198
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• 2016

전기 도금한 도금 층의 집합조직은 전해조건에 의해 변화하는 것으로 알려져 있다. 도금층의 집합조직은 도금층의 미세조직과 표면 형상과 관계가 있으며 도금층의 기계적인 성질에 영향을 미친다. 그러므로 도금층의 집합조직의 변화양상의 이해는 매우 중요하다. 또한 전기도금 층은 열처리 됐을 때 재결정이 일어난다. 그 재결정 집합조직은 도금 층의 초기 성장 집합조직과 다르게 된다. 전기 도금한 도금 층의 그 미세조직, 표면 형상, 집합조직과 기계적인 성질은 용액조성, 과전압, pH, 전류밀도와 용액온도 등의 전해조건에 의해 변화한다. (111)과 (110)집합조직을 갖는 구리도금 층을 융합연구를 통해 황산 욕으로부터 얻을 수 있었다. 이 연구에서는 (110) 또는 (111)집합조직을 갖는 구리도금 층을 황산 욕에서 얻고, 그 (110) 또는 (111)집합조직으로의 변화와 기계적 성질을 설명할 수 있는 모델을 제시하였다.

• 한국음향학회지
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• 제42권3호
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• pp.214-220
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• 2023

본 논문에서는 합성곱 신경망과 트랜스포머의 장점을 결합한 Conformer 모델을 이용하여 물체 표면의 질감특성을 나타내는 햅틱 가속도 신호로부터 질감 인식 성능을 향상시키는 방식을 제안한다. 제안한 방식에서는 사람이 스타일러스와 같은 도구를 이용하여 물체 표면과 접촉하는 동안 충격음과 진동에 의해 발생한 3축 가속도 신호를 1차원 가속도 데이터로 결합하고, 오디오 신호와 유사성을 갖는 햅틱 가속도 신호로부터 로그 멜-스펙트로그램을 추출한다. 그리고 추출된 로그 멜-스펙트로그램에 Conformer 모델을 적용하여 다양한 물체의 질감을 인식하는 데 있어 주요한 지역적 및 전역적인 주파수 특징을 학습한다. 제안된 모델의 성능 평가를 위해 60개의 재질로 구성된 Lehrstuhl für Medientechnik(LMT) 햅틱 질감 데이터세트를 실험한 결과 제안된 방식이 기존 방식들보다 물체 표면 재료의 질감을 효과적으로 잘 인식할 수 있음을 보였다.