• Title/Summary/Keyword: edges

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Moving target detection by using the hierarchical spatiotemporal filters with orientation selectivity (방향성 계층적 시공간 필터에 의한 움직이는 물체의 검출)

  • 최태완;김재창;윤태훈;남기곤
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.9
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    • pp.135-143
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    • 1996
  • In this paper, we popose a neural network that detects edges of moving objects in an image using a neural network of hierarchical spatial filter with orientation selectivity. We modify the temporal difference network by adding a self loop to each neuraon cell to reduce the problems of phantom edge detected by the neural network proposed by kwon yool et al.. The modified neural network alleviates the phantom edges of moving objects, and also can detect edges of miving objects even for the noisy input. By computer simulation with real images, the proposed neural netowrk can extract edges of different orientation efficiently and also can reduce the phantom edges of moving objects.

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An Initialization of Active Contour Models(Snakes) using Convex Hull Approximation

  • Kwak, Young-Tae
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.3
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    • pp.753-762
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    • 2006
  • The Snakes and GVF used to find object edges dynamically have assigned their initial contour arbitrarily. If the initial contours are located in the neighboring regions of object edges, Snakes and GVF can be close to the true boundary. If not, these will likely to converge to the wrong result. Therefore, this paper proposes a new initialization of Snakes and GVF using convex hull approximation, which initializes the vertex of Snakes and GVF as a convex polygonal contour near object edges. In simulation result, we show that the proposed algorithm has a faster convergence to object edges than the existing methods. Our algorithm also has the advantage of extracting whole edges in real images.

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A Morphological Study on the Incisal Edges of the Mandibular Incisal Teeth (하악절치절단(下顎切齒切端)의 형태학적(形態學的) 연구(硏究))

  • Kim, I.C.;Kwon, M.D.;Moh, K.J.;Lee, D.H.
    • The Journal of Korean Academy of Prosthodontics
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    • v.8 no.1
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    • pp.80-84
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    • 1968
  • Observing the morphology of the incisal edges, the time of the loss of mamelon, the decrement rate of the mamelon and the increment rate of the flat edges in the lower incisors among 576 Korean from 7 to 16 years old, the author obtained the following results; 1) The morphology of the incisal edges of the lower incisors immediately after completing eruption is as follows; The lower central incisors show that three nodule is around 65%, flat edge is around 27%, two nodule is around 7% and the central prominence of the incisal edge is 2% The lower lateral incisors show that three nodule is around 23%, flat edge is 24.5%, two nodule is 4 to 12% and the central prominence of the incisal edges around 44%. 2) The loss of mamelon may start at the age of 10. 3) The decrement rate of the mamelon beyond 12 years old is above 80% in the lower central incisors and 70% in the lower lateral incisors. 4) The increment rate of the flat edges beyond 11 years old is above 170% in the lower central incisors and 30% in the lower lateral incisors. 5) None of significant differences are found between right and left sides.

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Finite Difference Stability Analysis of Anisotropic Plates with Free Edge (자유경계를 갖는 비등방성 판의 유한차분 안정성 해석)

  • Yoo, Yong Min;Lee, Sang Youl;Chang, Suk Yoon
    • Journal of Korean Society of Steel Construction
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    • v.12 no.2 s.45
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    • pp.221-230
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    • 2000
  • Checking the stability of anisotropic plates with free edges, it is impossible that buckling loads and modes are found via existing classical methods about various loads and boundary conditions. For solving this problems. finite difference method(FDM) is used to analyze the buckling behaviors for arbitrary boundary conditions. Using FDM, it is difficult to treat the fictitious points on free edges. So, this paper analyzes buckling behaviors of analytic models with one edge free and the other edges clamped and with opposite two edges free and other two edges clamped. The various buckling loads and mode characteristics through numerical results are given for buckling behaviors of anisotropic plates on free edges.

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Bridge-edges Mining in Complex Power Optical Cable Network based on Minimum Connected Chain Attenuation Topological Potential

  • Jiang, Wanchang;Liu, Yanhui;Wang, Shengda;Guo, Jian
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.3
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    • pp.1030-1050
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    • 2021
  • The edges with "bridge characteristic" play the role of connecting the communication between regions in power optical cable network. To solve the problem of mining edges with "bridge characteristic" in provincial power optical cable network, the complex power optical cable network model is constructed. Firstly, to measure the generated potential energy of all nodes in n-level neighborhood local structure for one edge, the n-level neighborhood local structure topological potential is designed. And the minimum connected chain attenuation is designed to measure the attenuation degree caused by substituted edges. On the basis of that, the minimum connected chain attenuation topological potential based measurement is designed. By using the designed measurement, a bridge-edges mining algorithm is proposed to mine edges with "bridge characteristic". The experiments are conducted on the physical topology of the power optical cable network in Jilin Province. Compared with that of other three typical methods, the network efficiency and connectivity of the proposed method are decreased by 3.58% and 28.79% on average respectively. And the proposed method can not only mine optical cable connection with typical "bridge characteristic" but also can mine optical cables without obvious characteristics of city or voltage, but it have "bridge characteristic" in the topology structure.

Proposal of Minimum Spanning Tree Algorithm using 2-Edges Connected Grap (2-간선 연결 그래프를 사용한 최소신장트리 알고리즘 제안)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.4
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    • pp.233-241
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    • 2014
  • This paper suggests a fast minimum spanning tree algorithm which simplify the original graph to 2-edge connected graph, and using the cycling property. Borůvka algorithm firstly gets the partial spanning tree using cycle property for one-edge connected graph that selects the only one minimum weighted edge (e) per vertex (v). Additionally, that selects minimum weighted edge between partial spanning trees using cut property. Kruskal algorithm uses cut property for ascending ordered of all edges. Reverse-delete algorithm uses cycle property for descending ordered of all edges. Borůvka and Kruskal algorithms always perform |e| times for all edges. The proposed algorithm obtains 2-edge connected graph that selects 2 minimum weighted edges for each vertex firstly. Secondly, we use cycle property for 2-edges connected graph, and stop the algorithm until |e|=|v|-1 For actual 10 benchmark data, The proposed algorithm can be get the minimum spanning trees. Also, this algorithm reduces 60% of the trial number than Borůvka, Kruskal and Reverse-delete algorithms.

Numerical analysis of the combined aging and fillet effect of the adhesive on the mechanical behavior of a single lap joint of type Aluminum/Aluminum

  • Medjdoub, S.M.;Madani, K.;Rezgani, L.;Mallarino, S.;Touzain, S.;Campilho, R.D.S.G.
    • Structural Engineering and Mechanics
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    • v.83 no.5
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    • pp.693-707
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    • 2022
  • Bonded joints have proven their performance against conventional joining processes such as welding, riveting and bolting. The single-lap joint is the most widely used to characterize adhesive joints in tensile-shear loadings. However, the high stress concentrations in the adhesive joint due to the non-linearity of the applied loads generate a bending moment in the joint, resulting in high stresses at the adhesive edges. Geometric optimization of the bonded joint to reduce this high stress concentration prompted various researchers to perform geometric modifications of the adhesive and adherends at their free edges. Modifying both edges of the adhesive (spew) and the adherends (bevel) has proven to be an effective solution to reduce stresses at both edges and improve stress transfer at the inner part of the adhesive layer. The majority of research aimed at improving the geometry of the plate and adhesive edges has not considered the effect of temperature and water absorption in evaluating the strength of the joint. The objective of this work is to analyze, by the finite element method, the stress distribution in an adhesive joint between two 2024-T3 aluminum plates. The effects of the adhesive fillet and adherend bevel on the bonded joint stresses were taken into account. On the other hand, degradation of the mechanical properties of the adhesive following its exposure to moisture and temperature was found. The results clearly showed that the modification of the edges of the adhesive and of the bonding agent have an important role in the durability of the bond. Although the modification of the adhesive and bonding edges significantly improves the joint strength, the simultaneous exposure of the joint to temperature and moisture generates high stress concentrations in the adhesive joint that, in most cases, can easily reach the failure point of the material even at low applied stresses.

Edge Detection using Cost Minimization Method (비용 최소화 방법을 이용한 모서리 감지)

  • Lee, Dong-Woo;Lee, Seong-Hoon
    • Journal of Internet of Things and Convergence
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    • v.8 no.1
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    • pp.59-64
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    • 2022
  • Existing edge discovery techniques only found edges of defined shapes based on precise definitions of edges. Therefore, there are many limitations in finding edges for images of complex and diverse shapes that exist in the real world. A method for solving these problems and discovering various types of edges is a cost minimization method. In this method, the cost function and cost factor are defined and used. This cost function calculates the cost of the candidate edge model generated according to the candidate edge generation strategy. If a satisfactory result is obtained, the corresponding candidate edge model becomes the edge for the image. In this study, a new candidate edge generation strategy was proposed to discover edges for images of more diverse shapes in order to improve the disadvantage of only finding edges of a defined shape, which is a problem of the cost minimization method. In addition, the contents of improvement were confirmed through a simple simulation that reflected these points.

Minimum Spanning Tree with Select-and-Delete Algorithm (선택-삭제 최소신장트리 알고리즘)

  • Choi, Myeong-Bok;Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.4
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    • pp.107-116
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    • 2013
  • This algorithm suggests a method in which a minimum spanning tree can be obtained fast by reducing the number of an algorithm execution. The suggested algorithm performs a select-and-delete process. In the select process, firstly, it performs Borůvka's first stage for all the vertices of a graph. Then it re-performs Borůvka's first stage for specific vertices and reduces the population of the edges. In the delete process, it deletes the maximum weight edge if any cycle occurs between the 3 edges of the edges with the reduced population. After, among the remaining edges, applying the valency concept, it gets rid of maximum weight edges. Finally, it eliminates the maximum weight edges if a cycle happens among the vertices with a big valency. The select-and-delete algorithm was applied to 9 various graphs and was evaluated its applicability. The suggested select process is believed to be the vest way to choose the edges, since it showed that it chose less number of big edges from 6 graphs, and only from 3 graphs, comparing to the number of edges that is to be performed when using MST algorithm. When applied the delete process to Kruskal algorithm, the number of performances by Kruskal was less in 6 graphs, but 1 more in each 3 graph. Also, when using the suggested delete process, 1 graph performed only the 1st stage, 5 graphs till 2nd stage, and the remaining till 3rd stage. Finally, the select-and-delete algorithm showed its least number of performances among the MST algorithms.

The Early Stage Behavior of Unsteady Viscous Flows past an Impulsively Started Square Cylinder (급 출발하는 정방실린더 후류의 비정상 점성유동의 초기거동)

  • Jin, Dong-Sik;Jung, Jae-Hoon;Ahn, Cheol-O;Lee, Sang-Hwan
    • Proceedings of the KSME Conference
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    • 2001.06e
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    • pp.259-264
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    • 2001
  • High-resolution simulations using vortex methods have been performed for simulating unsteady viscous flows around an impulsively started square cylinder. In order to investigate the phenomenon from laminar to transition flow, simulations are performed for Reynolds numbers 25, 50, 150 and 250. At extremely low Reynolds number, flow around a square cylinder is known to separate at the trailing edges rather than the leading edges. With an increase of Reynolds number, the flow separation at the leading edges will be developed. The main flow characteristics of developing recirculation region and separations from leading and trailing edges are studied with the unsteady behavior of the wake after the cylinder starts impulsively. A notable change in the flow evolution is found at Re=150, that is, it is shown that the flow separations begin at both leading and trailing edges of the square cylinder. On the other hand, when Re=250, the strong secondary vorticity from the rear surfaces of the square cylinder increases the drag coefficient as the primary vortex layer is pushed outwards. The comparisons between results of the present study and experimental data show a good consistency.

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