• 한국CDE학회논문집
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• 제10권3호
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• pp.168-178
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• 2005

The Delaunay triangular net is primarily characterized by a balance of the whole by improving divided triangular patches into a regular triangle, which closely resembles an equiangular triangle. A triangular net occurring in certain, point-clustered, data is unique and can always create the same triangular net. Due to such unique characteristics, Delaunay triangulation is used in various fields., such as shape reconstruction, solid modeling and volume rendering. There are many algorithms available for Delaunay triangulation but, efficient sequential algorithms are rare. When these grids involve a set of points whose distribution are not well proportioned, the execution speed becomes slower than in a well-proportioned grid. In order to make up for this weakness, the ids are divided into sub-grids when the sets are integrated inside the grid. A method for finding a mate in an incremental construction algorithm is to first search the area with a higher possibility of forming a regular triangular net, while the existing method is to find a set of points inside the grid that includes the circumscribed sphere, increasing the radius of the circumscribed sphere to a certain extent. Therefore, due to its more efficient searching performance, it takes a shorer time to form a triangular net than general incremental algorithms.

• 복식
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• 제50권6호
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• pp.47-58
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• 2000

This paper analyses the geometric aspect of Soma Delaunay's works on the basis of design elements and principles. Geometric pattern is one of the distinct features of early 20th century avant-garde works. The significance of its pattern and colour comes from the fact that it has not only influenced the contemporary fine art but also offered the basic principle of modern costume design. In 1925 she was designing clothes which could be worn today without appearing old-fashioned. She foresaw the future trends in fashion and interior decoration, One might claim she belongs to the avant-garde even today and no less astonishing a phenomenon than she was in 1925. Soma Delaunay's art was one of the first expressions of abstract painting and her "simultaneous contrasts"are among the earliest example of the aesthete. In Delaunay's geometric abstraction it is found that the technique of"simultaneous contrasts" is exploited almost without exception. colour as well as collage was the favourite technique Delnaunay used in creating a distinct simultaneity, Many "inobjective" paintings as she herself called unite the rigour of simple geometric forms with an inner life and poetry which emanate from the richness of the colour, the musicality of the rhythm, the vibrant breadth of the execution.rant breadth of the execution.

• 대한기계학회논문집A
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• 제25권8호
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• pp.1246-1252
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• 2001

Reverse engineering has been widely used for the shape reconstruction of an object without CAD data and the measurement of clay or wood models for the development of new products. To generate a surface from measured points by a laser scanner, typical steps include the scanning of a clay or wood model and the generation of manufacturing data like STL file. A laser scanner has a great potential to get geometrical data of a model for its fast measuring speed and higher precision. The data from a laser scanner are composed of many line stripes of points. A new approach to remove point data with Delaunay triangulation is introduced to deal with problems during reverse engineering process. This approach can be used to reduce a number of measuring data from laser scanner within tolerance, thus it can avoid the time for handling point data during modelling process and the time for verifying and slicing STL model during RP process.

• 한국컴퓨터그래픽스학회논문지
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• 제6권4호
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• pp.23-28
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• 2000

본 논문은 평면 위의 n 개의 점에 대한 $L_{\infty}(L_1)$ 거리의 동적 디루니 삼각분할을 구축하는 방법을 소개한다. 이 방법은 $L_{\infty}(L_1)$ 거리 상에서 사분면 근접 그래프가 디루니 삼각분할에 포함되고 디루니 삼각분할에 있는 각 삼각형의 최소한 한 선분이 사분면 근접 그래프에 포함됨을 발견하고 이를 이용하여 레인지 트리 방법으로 동적 디루니 삼각분할을 구축한다. 본 방법은 $L_1(L_{\infty})$ 거리의 디루니 삼각분할에서 삽입과 삭제를 한 점 당 $O(log^2n)$ amortized 시간과 O(log n)의 expected 시간에 처리한다.

• 충청수학회지
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• 제34권4호
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• pp.387-395
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• 2021

In this paper, we give a characterization of a Delaunay surface in ℝ³. Let Σ be a CMC-H surface in ℝ³ with H ≠ 0. If Σ meets a plane with constant contact angle along a circle, then it is rotationally symmetric, i.e., Σ is part of a Delaunay surface.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2005년도 가을 학술발표논문집 Vol.32 No.2 (1)
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• pp.964-966
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• 2005

This paper proposes a distributed algorithm to maintain the Delaunay triangulation of moving points. We assume that every point is a processor which can only communicate with the adjacent points connected by edges in the Delaunay triangulation. The topology changes of the Delaunay triangulation due to the movement of the points are updated automatically by local operations of the points without any centralized processor or global information.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 제13회 신호처리 합동 학술대회 논문집
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• pp.721-724
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• 2000

This paper presents fingerprint authentication method based on minutiae quadrangle definded by neighboring two Delaunay triangles. In this method, we first make minutiae triangle through Delaunay triangulation which adaptively connect neighboring minutiae according to the local minutiae density distribution, and then use feature vectors in authentication which is extracted from the minutiae quadrangle formed by neighboring two minutiae triangles. This prevents the degradation of matching ratio caused by the errors in image processing or local deformation of the fingerprint, and we can authenticate more discriminately as this method reflects wider local area's topological features than the features extracted from the individual minutiae triangles. To evaluate the proposed algorithm's performance, experiment are conducted on 120 fingerprints, of which size is 256 ${\times}$ 364 with 500dpi resolution. Robust authentications are possible with low FRR.

• 전산구조공학
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• 제9권4호
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• pp.141-154
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• 1996

드로네이 요소생성기법은 모델링 영역의 모양에 구애받지 않으면서 요소의 크기제어, 재편성, 국지요소생성 등에 있어서 탁월한 기능을 보여주고 있다. 그러나 생성되는 요소가 선형삼각형요소임으로해서 비압축성 또는 대변위거동의 근사나 복잡한 형상의 영역의 기하학적 근사에 한계를 갖고 있다. 이를 보완하기 위해 기제시된 드로네이 요소생성 알고리즘을 바탕으로한 6절점 삼각요소 생성알고리즘을 제시하여 본 기법의 완성도를 높이고 이를 성형문제에 적용해 보였다.

• Journal of Information Processing Systems
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• 제14권2호
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• pp.435-447
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• 2018

Fingerprint-based biometric identification is one of the most interesting automatic systems for identifying individuals. Owing to the poor sensing environment and poor quality of skin, biometrics remains a challenging problem. The main contribution of this paper is to propose a new approach to recognizing a person's fingerprint using the fingerprint's local characteristics. The proposed approach introduces the barycenter notion applied to triangles formed by the Delaunay triangulation once the extraction of minutiae is achieved. This ensures the exact location of similar triangles generated by the Delaunay triangulation in the recognition process. The results of an experiment conducted on a challenging public database (i.e., FVC2004) show significant improvement with regard to fingerprint identification compared to simple Delaunay triangulation, and the obtained results are very encouraging.

• 로봇학회논문지
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• 제5권1호
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• pp.41-47
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• 2010

This paper proposes a path planning method of a mobile robot in two-dimensional work space. The path planning method is based on a cell decomposition approach. To create a path which consists of a number of line segments, the Delaunay Triangulation algorithm is used. Using the cells produced by the Delaunay Triangulation algorithm, a mesh generation algorithm connects the starting position to the goal position. Dijkstra algorithm is used to find the shortest distance path. Greedy algorithm optimizes the path by deleting the path segments which detours without collision with obstacles.