• Title/Summary/Keyword: Edges

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A Study of the Classificationa Society Rules on The Thicknesses of The Bulkhead Platings. (격벽판(隔壁板)의 두께에 관한 각선급협회규칙(各船級協會規則)의 비교연구(比較硏究))

  • J.H.,Hwang;S.J.,Yim
    • Bulletin of the Society of Naval Architects of Korea
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    • v.1 no.1
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    • pp.3-8
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    • 1964
  • The classification society rules [1], [2], [3], [4] on the thicknesses of the bulkhead platings are represented graphically. Fig. 1 shows that every rule value for the thickness of the ordinary watertight bulkhead plating is than theoretical value calculated by Timoshenko's formula (1) for ${\sigma}_y=35,000$ psi and k=0.4998. When a flooding due to damage occurred, however, the stiffened edges would yield and clamped edges would change to plastic hinges. In such case, the maximum bending stress at the clamped edges are reduced considerably. The rule values, therefore, are supposed to be acceptable in spite of their insufficient scantlings compared with the values calculated by (2). In the ordinary watertight bulkhead platings A.B.S. Rules give the largest scantlings of all. Fig. 2 shows that A.B.S. Rules and K.R.-N.K. Rules give larger values than the calculated by (2) for deep tank bulkhead platings. But Lloyd Rules give the smaller thickness than equation (2). The special requirements for corrosion bulkhead platings are not studied here.

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An Efficient Edge Detection Using Van der Waerden′s Statistic in Images (Van der Waerden의 통계량을 이용한 영상에서의 효율적인 에지검출기법)

  • 최명희;이호근;김주원;하영호
    • Proceedings of the IEEK Conference
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    • 2002.06d
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    • pp.215-218
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    • 2002
  • The edges of an image hold much of the information in that image. The edges tell where objects are, their shape and size, and something about their texture. An edge is where the intensity of an image moves from a low value to a high value. We introduce the edge detection using the differential operator with Sobel operator and describe a nonparametric Wilcoxon test based on statistical hypothesis testing for the detection of edges. This paper proposes an efficient edge detection using Van der Waerden's statistic in original and noisy images. We use the threshold determined by specifying significance level a and an edge-height parameter. Comparison with our statistical test and Sobel operator shows that Van der Waerden method perform more effectively in both noisy and noise-free images.

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Vertical Edge Based Algorithm for Korean License Plate Extraction and Recognition

  • Yu, Mei;Kim, Yong Deak
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.7A
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    • pp.1076-1083
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    • 2000
  • Vehicle license plate recognition identifies vehicle as a unique, and have many applications in traffic monitoring field. In this paper, a vertical edge based algorithm to extract license plate within input gray-scale image is proposed. A size-and-shape filter based on seed-filling algorithm is applied to remove the edges that are impossible to be the vertical edges of license plate. Then the remaining edges are matched with each other according to some restricted conditions so as to locate license plate in input image. After license plate is extracted. normalized and segmented, the characters on it are recognized by template matching method. Experimental results show that the proposed algorithm can deal with license plates in normal shape effectively, as well as the license plates that are out of shape due to the angle of view.

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Cycles in Conditional Faulty Enhanced Hypercube Networks

  • Liu, Min;Liu, Hongmei
    • Journal of Communications and Networks
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    • v.14 no.2
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    • pp.213-221
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    • 2012
  • The architecture of an interconnection network is usually represented by a graph, and a graph G is bipancyclic if it contains a cycle for every even length from 4 to ${\mid}V(G){\mid}$. In this article, we analyze the conditional edge-fault-tolerant properties of an enhanced hypercube, which is an attractive variant of a hypercube that can be obtained by adding some complementary edges. For any n-dimensional enhanced hypercube with at most (2n-3) faulty edges in which each vertex is incident with at least two fault-free edges, we showed that there exists a fault-free cycle for every even length from 4 to $2^n$ when n($n{\geq}3$) and k have the same parity. We also show that a fault-free cycle for every odd length exists from n-k+2 to $2^n-1$ when n($n{\geq}2$) and k have the different parity.

A Study on a New Locally Adaptive Edge Operator (신국부 적응 에지 연산자에 관한 연구)

  • 정규성;박래홍
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.5
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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.

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Free Vibrations and Buckling of Rectangular Plates with Linearly Varying In-Plane Loading

  • Chang, Kyong-Ho;Shim, Hyun-Ju;Kang, Jae-Hoon
    • Journal of Korean Association for Spatial Structures
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    • v.4 no.4 s.14
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    • pp.99-111
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    • 2004
  • An exact solution procedure is formulated for the free vibration and buckling analysis of rectangular plates having two opposite edges simply supported when these edges are subjected to linearly varying normal stresses. The other two edges may be clamped, simply supported or free, or they may be elastically supported. The transverse displacement (w) is assumed as sinusoidal in the direction of loading (x), and a power series is assumed in the lateral (y) direction (i.e., the method of Frobenius). Applying the boundary conditions yields the eigenvalue problem of finding the roots of a fourth order characteristic determinant. Care must be exercised to obtain adequate convergence for accurate vibration frequencies and buckling loads, as is demonstrated by two convergence tables. Some interesting and useful results for vibration frequencies and buckling loads, and their mode shapes, are presented for a variety of edge conditions and in-plane loadings, especially pure in-plane moments.

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An Algorithm for the Edge Coloring Problem (호의 색칠문제의 해법)

  • Park, Sung-Soo
    • Journal of Korean Institute of Industrial Engineers
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    • v.18 no.2
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    • pp.43-49
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    • 1992
  • Edge coloring problem is to find a minimum cardinality coloring of the edges of a graph so that any pair of edges incident to a common node do not have the same colors. Edge coloring problem is NP-hard, hence it is unlikely that there exists a polynomial time algorithm. We formulate the problem as a covering of the edges by matchings and find valid inequalities for the convex hull of feasible solutions. We show that adding the valid inequalities to the linear programming relaxation is enough to determine the minimum coloring number(chromatic index). We also propose a method to use the valid inequalities as cutting planes and do the branch and bound search implicitly. An example is given to show how the method works.

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Stereo matching algorithm based on systolic array architecture using edges and pixel data (에지 및 픽셀 데이터를 이용한 어레이구조의 스테레오 매칭 알고리즘)

  • Jung, Woo-Young;Park, Sung-Chan;Jung, Hong
    • Proceedings of the KIEE Conference
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    • 2003.11c
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    • pp.777-780
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    • 2003
  • We have tried to create a vision system like human eye for a long time. We have obtained some distinguished results through many studies. Stereo vision is the most similar to human eye among those. This is the process of recreating 3-D spatial information from a pair of 2-D images. In this paper, we have designed a stereo matching algorithm based on systolic array architecture using edges and pixel data. This is more advanced vision system that improves some problems of previous stereo vision systems. This decreases noise and improves matching rate using edges and pixel data and also improves processing speed using high integration one chip FPGA and compact modules. We can apply this to robot vision and automatic control vehicles and artificial satellites.

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Free Vibration Analysis of Arbitrarily Shaped Polygonal Plates with Free Edges by Considering the Phenomenon of Stress Concentration at Corners (꼭지점에서의 응력 집중 현상을 고려한 자유단 경계조건을 가진 임의 다각형 형상 평판의 자유 진동 해석)

  • Kang, Sang-Wook
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.17 no.3 s.120
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    • pp.220-225
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    • 2007
  • Free vibration analysis using the method of NDIF (non-dimensional dynamic influence function), which was developed by the author, is extended to arbitrarily shaped polygonal plates with free edges. Local Cartesian coordinate systems are employed to apply the free boundary condition to nodes distributed along the edges of the plate of interest. Furthermore, a new way for applying the free boundary condition to nodes located at corners of the plate is for the first time introduced by considering the phenomenon of stress concentration at the corners. Two case studies show that the proposed method is valid and accurate when the eigenvalues by the proposed method are compared to those by FEM(ANSYS).

ASYMPTOTIC NUMBERS OF GENERAL 4-REGULAR GRAPHS WITH GIVEN CONNECTIVITIES

  • Chae, Gab-Byung
    • Bulletin of the Korean Mathematical Society
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    • v.43 no.1
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    • pp.125-140
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    • 2006
  • Let $g(n,\;l_1,\;l_2,\;d,\;t,\;q)$ be the number of general4-regular graphs on n labelled vertices with $l_1+2l_2$ loops, d double edges, t triple edges and q quartet edges. We use inclusion and exclusion with five types of properties to determine the asymptotic behavior of $g(n,\;l_1,\;l_2,\;d,\;t,\;q)$ and hence that of g(2n), the total number of general 4-regular graphs where $l_1,\;l_2,\;d,\;t\;and\;q\;=\;o(\sqrt{n})$, respectively. We show that almost all general 4-regular graphs are 2-connected. Moreover, we determine the asymptotic numbers of general 4-regular graphs with given connectivities.