• 제목/요약/키워드: 3D Patches

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3차원 사이버도시구축을 위한 그래디언트기반 3차원 평면추출기법의 지형 및 인공지물지역에의 적용에 관한 연구 (Application of the Gradient-Based 3D Patch Extraction Method to Terrain and Man-made Objects for Construction of 3D CyberCity)

  • 서수영
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2010년 춘계학술발표회 논문집
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    • pp.227-229
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    • 2010
  • This study presents an application of the 3D patch extraction method which is based on gradient-driven properties to obtain 3D planar patches over the terrain and man-made objects from lidar data. The method which was exploited in this study is composed of a sequence of processes: segmentation by slope, initiation of triggering patches by mode selection, and expansion of the triggering patches. Since urban areas contain many planar regions over the terrain surface, application of the method has been experimented to extract 3D planar patches not only from non-terrain objects but also from the terrain. The experimental result shows that the method is efficient to acquire 3D planar patches.

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SVM 모델을 이용한 3차원 패치 기반 단백질 상호작용 사이트 예측기법 (Prediction of Protein-Protein Interaction Sites Based on 3D Surface Patches Using SVM)

  • 박성희
    • 정보처리학회논문지D
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    • 제19D권1호
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    • pp.21-28
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    • 2012
  • 모노머 단백질의 상호작용 사이트 예측은 기능을 알지 못하는 단백질에 대해서 이것과 상호작용하는 단백질로부터 기능을 예측하거나 단백질 도킹을 위한 검색 공간의 감소에 중요한 역할을 한다. 그러나 상호작용사이트 예측은 대부분 단백질 상호작용이 세포 내에서 순간적 반응에 일어나는 약한 상호작용으로 실험에 의한 3차원 결정 구조 식별의 어려움이 따르며 이로 인해 3차원의 복합체 데이터가 제한적으로 양산된다. 이 논문에서는 모노머 단백질의 3차원 패치 계산을 통하여 구조가 알려진 복합체의 상호작용사이트와 비상호작용사이트에 대한 패치 속성을 추출하고 이를 기반으로 Support Vector Machine (SVM) 분류기법을 이용한 예측 모델 개발을 제시한다. 타겟 클래스의 데이터 불균형 문제 해결을 위해 under-sampling 기법을 이용한다. 사용된 패치속성은 2차 구조 요소와 아미노산 구성으로부터 총 9개가 추출된다. 147개의 단백질 복합체에 대해서 10 fold cross validation을 통해서 다양한 분류모델의 성능 평가를 하였다. 평가한 분류 모델 중 SVM은 92.7%의 높은 정확성을 보이고 이를 이용하여 분류 모델을 개발하였다.

불규칙한 3차원 상의 점군들에 대한 삼각곡면 보간에 관한 연구 (A Study of Triangular Surface Interpolant for Scattered 3D points)

  • 주상윤
    • 대한산업공학회지
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    • 제19권2호
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    • pp.75-82
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    • 1993
  • This paper deals with a systematic procedure for constructing a triangular composite surface which is interpolated from given scattered 3-D points. The procedure consists of a triangulation, construction of curve net, and interpolation of triangular patches. An obtained surface is composed of cubic triangular patches, which are $G^1$ continuous to adjacent other patches.

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그래픽스 하드웨어를 이용한 입체 스윕 경계 근사 (Approximating 3D General Sweep Boundary using Graphics Hardware)

  • 안재우;김명수;홍성제
    • 한국컴퓨터그래픽스학회논문지
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    • 제8권3호
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    • pp.1-7
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    • 2002
  • This paper presents a practical technique for approximating the boundary surface of the volume swept out by three-dimensional objects using the depth-buffer. Objects may change their geometries and orientations while sweeping. The sweep volume is approximated as a union of volume elements, which are just rendered inside appropriate viewing frusta of virtual cameras and mapped into screen viewports with depth-buffer. From the depth of each pixel in the screen space of each rendering, the corresponding point in the original world space can be computed. Appropriately connecting these points yields polygonal faces forming polygonal surface patches approximately covering some portion of the sweep volume. Each view frustum adds one or more surface patches in this way, and these presumably overlapped polygonal surface patches approximately enclose the whole sweep volume. These patches may further be processed to yield non-overlapped polygonal surfaces as an approximation to the boundary of the original 3D sweep volume.

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3차원 물체의 이동방향 측정에 관한 연구 (A Study on the closed-form solutions to image flow equations for 3D structure and motion)

  • 이현정;조동섭
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1990년도 하계학술대회 논문집
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    • pp.546-549
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    • 1990
  • This study introduces the three-dimensional information about moving objects. Relative motion between textured objects and observer generates a time varying optic array at the image, from which image motion of contours can be extracted. Closed-form solutions are proposed for the structure and motion of planar and curved surface patches. The analytic solution for curved surface patches combines the transformation of Longuet-Higgins with the planar surface solution of Subbarao and Waxman. Ovoid patches are shown to construct a unique transform angle. Thus, ovoid patches almost always yield a unique 3D interpretation.

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도파기와 기생 패치를 이용한 직렬-급전 다이폴 쌍 안테나의 이득 향상 (Gain Enhancement of Series-fed Dipole Pair Antenna Using Director and Parasitic Patches)

  • 여준호;이종익
    • 한국정보통신학회논문지
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    • 제21권10호
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    • pp.1855-1861
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    • 2017
  • 본 논문에서는 한 개의 도파기, 두 개의 기생 패치를 이용하여 이중 직렬-급전 다이폴 쌍 안테나(series-fed dipole pair antenna; SDPA)의 이득을 향상시키는 방법에 관하여 연구하였다. 변형된 밸런을 이용하여 대역폭을 늘리고, 한 개의 도파기와 두 개의 기생 패치를 추가하여 중간 및 고주파수 대역에서 이득을 높였다. 도파기와 기생 패치 사이의 거리에 따른 안테나의 특성 변화를 분석하여 1.55-2.98 GHz 대역에서 7 dBi 이상의 이득을 갖는 SDPA를 설계하였다. 성능 검증을 위해 제안된 SDPA를 $90mm(L){\times}135mm(W)$의 크기로 FR4 기판 위에 제작하였다. 제작된 안테나는 전압 정재파비(voltage standing wave ratio; VSWR)가 2 이하인 대역이 1.56-3.10 GHz으로 나왔다. 또한 1.54-3.00 GHz 대역에서 이득이 7 dBi 이상을 유지하는 것을 확인하였다.

Triangle Simplification에 의한 3D 인체형상분할과 삼각조합방법에 의한 2D 패턴구성 (Method of 3D Body Surface Segmentation and 2D Pattern Development Using Triangle Simplification and Triangle Patch Arrangement)

  • 정연희;홍경희;김시조
    • 한국의류학회지
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    • 제29권9_10호
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    • pp.1359-1368
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    • 2005
  • When we develop the tight-fit 2D pattern from the 3D scan data, segmentation of the 3D scan data into several parts is necessary to make a curved surface into a flat plane. In this study, Garland's method of triangle simplification was adopted to reduce the number of data point without distorting the original shape. The Runge-Kutta method was applied to make triangular patch from the 3D surface in a 2D plane. We also explored the detailed arrangement method of small 2D patches to make a tight-fit pattern for a male body. As results, minimum triangle numbers in the simplification process and efficient arrangement methods of many pieces were suggested for the optimal 2D pattern development. Among four arrangement methods, a block method is faster and easier when dealing with the triangle patches of male's upper body. Anchoring neighboring vertices of blocks to make 2D pattern was observed to be a reasonable arrangement method to get even distribution of stress in a 2D plane.

3-D fracture analysis of cracked aluminum plates repaired with single and double composite patches using XFEM

  • Jamal-Omidi, Majid;Falah, Mehdi;Taherifar, Davood
    • Structural Engineering and Mechanics
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    • 제50권4호
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    • pp.525-539
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    • 2014
  • Bonded composite-patch repair has been widely used to restore or extend the service life of damaged structures due to its effectiveness as a mechanical repair technique. In this paper using extended finite element method (XFEM), three-dimensional crack models are developed to examine the fracture behavior of centrally cracked aluminum plates repaired with single and double sided composite patches. Stress intensity factor (SIF) at the crack tip is used as the fracture criterion. In this regard, the effects of the crack lengths, patch materials, orientation of plies, adhesive and patch thickness are examined to estimate the SIF of the repaired plate and the repair performance. The obtained results show that composite patches have significant effect on reduction of the SIF at the crack tip. It is also proved that using double symmetric repair, in comparison to single one, reduces considerably SIF at the crack tip. Hence, the residual strength can be improved significantly as well as fatigue life of the structure. Investigation of ply orientation effects shows SIF increase as the ply orientation is changed from $0^{\circ}$ (perpendicular to the advancing crack) to $90^{\circ}$ (parallel to the crack line). However, the effectiveness of the ply orientation depends on the loading direction and the crack direction.

Bio-Inspired Micro/Nanostructures for Functional Applications: A Mini-Review

  • Young Jung;Inkyu Park
    • 센서학회지
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    • 제32권1호
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    • pp.31-38
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    • 2023
  • Three-dimensional (3D) micro/nanostructures based on soft elastomers have received extensive attention in recent years, owing to their potential and advanced applicability. Designing and fabricating 3D micro/nanostructures are crucial for applications in diverse engineering fields, such as sensors, harvesting devices, functional surfaces, and adhesive patches. However, because of their structural complexity, fabricating soft-elastomer-based 3D micro/nanostructures with a low cost and simple process remains a challenge. Bio-inspired designs that mimic natural structures, or replicate their micro/nanostructure surfaces, have greatly benefited in terms of low-cost fabrication, scalability, and easy control of geometrical parameters. This review highlights recent advances in 3D micro/nanostructures inspired by nature for diverse potential and advanced applications, including flexible pressure sensors, energy-harvesting devices based on triboelectricity, superhydrophobic/-philic surfaces, and dry/wet adhesive patches.

의류 패턴 설계를 위한 삼차원 인체 체표면 스캔 데이터 활용에 관한 연구 (A Study on the Use of 3D Human Body Surface Shape Scan Data for Apparel Pattern Making)

  • 천종숙;서동애;이관석
    • 복식문화연구
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    • 제10권6호
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    • pp.709-717
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    • 2002
  • In the apparel industry, the technology has been advanced rapidly. The use of 3D scanning systems fur the capture and measurement of human body is becoming common place. Three dimensional digital image can be used for design, inspection, reproduction of physical objects. The purpose of this study is to develop a method that drafts men's basic bodice pattern from scanned 3D body surface shape data. In order to pursue this purpose the researchers developed pattern drafting algorithm. The 3D scanner used in this study was Cyberware Whole Body Scanner WB-4. The bodice pattern drafting algorithm from 3D body surface shape data developed in this study is as follows. First, convert geometric 3D body surface data to 3D polygonal mesh data. Second, develop algorithm to lay out 3D polygonal patches onto a plane using Auto Lisp program. The polygon meshes are coplanar, and the individual mesh is continuously in contact with next one The bodice front surface shape data in polygonal patches form was lined up in bust and waist levels. The back bodice was drafted by lining up the polygonal mesh in scapula, chest, and waist levels. in the drafts, gaps between polygons were formed into the darts.

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