• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2007년도 하계종합학술대회 논문집
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• pp.389-390
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• 2007

In this paper, we propose a modified watershed algorithm to obtain exact edge of region. The proposed method adjusts priority at zero-crossing point of gradient in order to make the point of region decision time postponed. We compare the proposed method with a previous method and prove that this method can extract more correct edge of region.

• 한국멀티미디어학회논문지
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• 제13권10호
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• pp.1463-1473
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• 2010

본 논문에서는 정확한 경계 추출 및 수행시간 단축을 위한 개선된 워터쉐드 알고리즘을 제안한다. 본 논문에서는 두 가지 새로운 알고리즘을 제안한다. 첫 번째는 기존 강우방식과 침수방식의 워터쉐드 확장 방식을 복합적으로 적용한 것이다. 먼저 각 방식의 장점과 단점을 규명하고 장점은 유지하고 단점은 보완하여 정확한 경계를 추출하면서도 수행시간을 단축할 수 있는 새로운 확장방식을 제안한다. 두 번째는 보다 정확한 경계를 얻기 위한 새로운 우선순위 결정 알고리즘이다. 기울기의 영교차점은 경계로 예상되는 위치이지만 기존의 워터쉐드 알고리즘은 이러한 위치를 경계로 추출하지 못하는 한계를 가지고 있다. 따라서 보다 정확한 경계를 추출할 수 있도록 워터쉐드를 위한 새로운 우선순위 결정 알고리즘을 제안한다. 모의실험을 통해 제안된 알고리즘과 기존 알고리즘을 비교하고 제안된 방법이 보다 정확한 경계를 추출할 수 있음을 보인다.

• 대한전자공학회논문지
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• 제24권5호
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• pp.841-848
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• 1987

This paper presents a new two-stage edge detection algorithm which can give thin edges and can find edges between low contrast regions. In the first stage, the potential edge points are obtained using the proposed edge operator which is motivated by the concept of the E filter. And in the second stage, the real edge points adre detected by comparing the potential edge values with the lically adaptive threshold values of the corresponding potential edge points and by testing whether the potential edge points are zero-crossing points or not. It is shown quantitatively that the proposed algorithm can find edges effectively in an image with impulse noise, and also the results of applying the proposed algorithm to real images are presented.

• 한국도로학회논문집
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• 제16권1호
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• pp.91-98
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• 2014

PURPOSES : Recently, there are increasing bicycle accidents along with increasing bicycles users. Bicycle accidents occurred frequently by perpendicular collision form at intersection inner. In order to improve safety of bicycle, drivers need to be aware of bicycles on the road and intersection geometric designs need to be designed to reduce risk associated with collisions between bicycles and car. This study aims to review the location of bicycle crossing in the viewpoint of bicycle safety. METHODS : Four types of bicycle crossing by curve radius and driver's check around the behavior are set to simulate the risk of collisions between bicycles and car turning right. Simulation using fortran programming are conducted on total 60 cases. RESULTS : Bicycle crossing located behind of crosswalk is lower the risk of collisions with car in all cases. In addition to the larger curve radius of pavement edge at intersection and the more pay attention to the rear by the turn head to the right is too low the risk of collisions with car. CONCLUSIONS : It is show that the location of bicycle crossing is safer behind than in front of crosswalk in the viewpoint of bicycle safety.

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 2003년도 춘계학술발표대회논문집
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• pp.431-434
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• 2003

In this paper, we propose an efficient method not only f3r producing accurate region segmentation, solving the over-segmentation problem of watershed algorithm but also f3r reducing post-processing time by reducing computation loads. Through this proposed method, region segmentation of neighboring objects and discrimination of similar intensities were effectively obtained. Input image of watershed algorithm has used the derivative-based detectors such as Sobel and Canny. But proposed method uses the pixels-similarity-based detector, that is, SUSAN. By adopting this proposed method, we can reduce the noise problem and solve the problem of over-segmentation and not lose the edge information of objects. We also propose Zero-Crossing SUSAN. With Zero-Crossing SUSAN, the edge localization, times and computation loads can be improved over those obtained from existing SUSAN

• 한국정보과학회논문지:소프트웨어및응용
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• 제36권11호
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• pp.875-890
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• 2009

대사체학은 대사 경로 네트워크를 통해 생명 활동을 이해하고자 하는 분야로서, 대사 경로 내의 흐름을 한 눈에 알 수 있도록 가시화하여 보여 주는 도구가 반드시 필요하다. 이러한 가시화 도구의 경우 노드수가 증가할수록 에지 교차가 기하급수적으로 증가하는 문제가 있다. 따라서 유전체 수준의 대사경로를 연구하기 위해서는 대사 경로 그래프 레이아웃 상에 나타나는 에지 교차를 줄이는 것이 시각화의 매우 중요한 부분이다. 본 논문에서는 대사 경로의 구조적인 특징에 기반한 3차원 공간 상에 대사 경로 그래프를 레이아웃해 주는 모듈을 설계, 구현하였다. 2-계층 레이아웃을 이용하여 대사 경로 그래프를 계층적으로 레이아웃함으로써 표현영역을, 3차원으로 확장시키고 기존의 2차원 레이아웃 알고리즘 적용시 번번히 나타나는 에지 교차의 수를 감소시키는 결과를 얻었다.

• 한국인터넷방송통신학회논문지
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• 제24권4호
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• pp.89-97
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• 2024

수레바퀴 중심축(허브, 정점)이 요구하는 살(간선)을 교차없이 연결하여 모든 중심축이 연결된 망을 형성하는 수레바퀴 살 퍼즐 문제는 연구의 불모지라 할 수 있다. 이 문제에 대해서는 지수시간이 소요되는 전수 탐색법이나 분기 한정 법조차도 제시된 알고리즘이 없는 실정이다. 본 논문은 주어진 SP에 대해 m×n의 교차 대각선을 가진 격자 그래프를 작도하고, 잉여 간선을 전정(삭제)하는 알고리즘을 제안하였다. 제안된 알고리즘은 간선 수가 허브 요구량과 일치하는 허브의 간선을 선택하고 이와 교차하는 간선을 삭제하는 단순한 방법이다. 만약 허브 요구량을 충족하는 간선을 가진 허브가 존재하지 않으면 여유 량이 최대인 허브의 간선을 우선하여 삭제(전정)하는 전략을 채택하였다. 제안된 알고리즘을 20개의 벤치마킹 실험 데이터에 적용한 결과 모든 문제에 대해 시행착오 회수를 최소로 하는 해를 구할 수 있음을 보였다.

• Journal of Biosystems Engineering
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• 제30권6호통권113호
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• pp.366-372
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• 2005

The objective of this study was to evaluate the bump crossing and loading stability of a proto-type mini-forwarder under development. The evaluation was performed by computer simulation using a multi-body dynamic analysis program, Recur- Dyn 5.21. The proto-type was modeled and its properties such as mass, mass center, and mass moment of inertia were determined using 3D CAD modeler, Solid Edge 8.0. The $\%$ errors of masses, mass center, mass moment of inertia, and vertical motion of the model were within less than $10\%$ and the model's behavior agreed relatively well with those of the proto-type when traversing over a rectangular bump. Using the validated model, bump crossing of the proto-type was simulated and the loading limit was determined. It was found that effects of the shapes of bump on the bump crossing performance was insignificant within the practical heights of bumps. Stability of bump crossing increased with loading. However, loading of longer logs than 2.7 m made the crossing unstable because the ends of logs contacted ground when traversing over the bump. The maximum loading capacity of the proto-type was estimated to be 7.8 kN of 2.7 m long logs.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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• pp.1360-1363
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• 1987

Two edge detection methods are devised and tested. First one makes use of mean-difference between two connected regions after bimodal thresholding within a local window. It appears experimentally to provide reduced edge width maintaining good connectivity. It seems due to the use of the threshold obtained from a larger neighborhood. Second one uses additionally the gradient information to detect approximate zero crossing points of second directional derivative. This provides edges thinned nearly to one pixel width.

• 한국CDE학회논문집
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• 제4권3호
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• pp.173-179
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• 1999

In reverse engineering, when a shape containing multi-patched surfaces is digitized, the boundaries of these surfaces should be detected. The objective of this paper is to introduce a computationally efficient segmentation technique for extracting edges, ad partitioning the 3D measuring point data based on the location of the boundaries. The procedure begins with the identification of the edge points. An automatic edge-based approach is developed on the basis of local geometry. A parametric quadric surface approximation method is used to estimate the local surface curvature properties. the least-square approximation scheme minimizes the sum of the squares of the actual euclidean distance between the neighborhood data points and the parametric quadric surface. The surface curvatures and the principal directions are computed from the locally approximated surfaces. Edge points are identified as the curvature extremes, and zero-crossing, which are found from the estimated surface curvatures. After edge points are identified, edge-neighborhood chain-coding algorithm is used for forming boundary curves. The original point set is then broke down into subsets, which meet along the boundaries, by scan line algorithm. All point data are applied to each boundary loops to partition the points to different regions. Experimental results are presented to verify the developed method.