• Title/Summary/Keyword: line linking

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Line feature extraction in a noisy image

  • Lee, Joon-Woong;Oh, Hak-Seo;Kweon, In-So
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.137-140
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    • 1996
  • Finding line segments in an intensity image has been one of the most fundamental issues in computer vision. In complex scenes, it is hard to detect the locations of point features. Line features are more robust in providing greater positional accuracy. In this paper we present a robust "line features extraction" algorithm which extracts line feature in a single pass without using any assumptions and constraints. Our algorithm consists of five steps: (1) edge scanning, (2) edge normalization, (3) line-blob extraction, (4) line-feature computation, and (5) line linking. By using edge scanning, the computational complexity due to too many edge pixels is drastically reduced. Edge normalization improves the local quantization error induced from the gradient space partitioning and minimizes perturbations on edge orientation. We also analyze the effects of edge processing, and the least squares-based method and the principal axis-based method on the computation of line orientation. We show its efficiency with some real images.al images.

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Efficient Classification of High Resolution Imagery for Urban Area

  • Lee, Sang-Hoon
    • Korean Journal of Remote Sensing
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    • v.27 no.6
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    • pp.717-728
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    • 2011
  • An efficient method for the unsupervised classification of high resolution imagery is suggested in this paper. It employs pixel-linking and merging based on the adjacency graph. The proposed algorithm uses the neighbor lines of 8 directions to include information in spatial proximity. Two approaches are suggested to employ neighbor lines in the linking. One is to compute the dissimilarity measure for the pixel-linking using information from the best lines with the smallest non. The other is to select the best directions for the dissimilarity measure by comparing the non-homogeneity of each line in the same direction of two adjacent pixels. The resultant partition of pixel-linking is segmented and classified by the merging based on the regional and spectral adjacency graphs. This study performed extensive experiments using simulation data and a real high resolution data of IKONOS. The experimental results show that the new approach proposed in this study is quite effective to provide segments of high quality for object-based analysis and proper land-cover map for high resolution imagery of urban area.

Contour Parallel Offset and Tool-Path Linking Algorithm for Pocketing Using Pairwise Intersection Approach (Pairwise Intersection 방식을 이용한 윤곽 오프셋 및 공구경로 연결 알고리즘)

  • Huh, Jin-Hun;Kim, Yeoung-Il;Jun, Cha-Soo
    • Korean Journal of Computational Design and Engineering
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    • v.11 no.5
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    • pp.375-383
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    • 2006
  • Presented in this paper is a new fast and robust algorithm generating NC tool path for 2D pockets with islands. The input shapes are composed of line segments and circular arcs. The algorithm has two steps: creation of successive offset loops and linking the loops to a tool path. A modified pairwise technique is developed in order to speed up and stabilize the offset process, and the linking algorithm is focused on avoiding thin-wall cutting and minimizing tool retractions. The proposed algorithm has been implemented in C++ and some illustrative examples are presented to show the practical strength of the algorithm.

Building Detection Using Segment Measure Function and Line Relation

  • Ye, Chul-Soo;Kim, Gyeong-Hwan;Lee, Kwae-Hi
    • Proceedings of the KSRS Conference
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    • 1999.11a
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    • pp.177-181
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    • 1999
  • This paper presents an algorithm for building detection from aerial image using segment measure function and line relation. In the detection algorithm proposed, edge detection, linear approximation and line linking are used and then line measure function is applied to each line segment in order to improve the accuracy of linear approximation. Parallelisms, orthogonalities are applied to the extracted liner segments to extract building. The algorithm was applied to aerial image and the buildings were accurately detected.

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Line Drawings from 2D Images (이차원 영상의 라인 드로잉)

  • Son, Min-Jung;Lee, Seung-Yong
    • Journal of KIISE:Computer Systems and Theory
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    • v.34 no.12
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    • pp.665-682
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    • 2007
  • Line drawing is a widely used style in non-photorealistic rendering because it generates expressive descriptions of object shapes with a set of strokes. Although various techniques for line drawing of 3D objects have been developed, line drawing of 2D images has attracted little attention despite interesting applications, such as image stylization. This paper presents a robust and effective technique for generating line drawings from 2D images. The algorithm consists of three parts; filtering, linking, and stylization. In the filtering process, it constructs a likelihood function that estimates possible positions of lines in an image. In the linking process, line strokes are extracted from the likelihood function using clustering and graph search algorithms. In the stylization process, it generates various kinds of line drawings by applying curve fitting and texture mapping to the extracted line strokes. Experimental results demonstrate that the proposed technique can be applied to the various kinds of line drawings from 2D images with detail control.

On-Line Upgrade of Dynamic Linking Library (DLL) in the UNIX Environment (유닉스 환경에서의 DLL의 동적 업그레이드)

  • 김화준;이인환
    • Proceedings of the Korean Information Science Society Conference
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    • 1998.10b
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    • pp.660-660
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    • 1998
  • 본 논문은 SUN Solaris 2.6 환경에서 동작 중인 Dynamic Linking Library (DLL)를, 이 DLL을 사용하는 응용 프로그램의 동작에 영향을 주지 않고 온라인으로 교체하기 위한 방법을 제시한다. 구체적으로 이 논문은 Solaris 환경에서의 동적 링킹의 방법과 구조를 분석하고, 이로부터 DLL을 온라인으로 업그레이드하기 위한 교체 환경과 절차 및 방법을 제시하며, 실제 업그레이드를 통해 제시된 방법의 기능을 확인한다. 또한 제시된 방법을 동적 링킹을 사용하지 않은 일반 실행 파일의 온라인 교체에 활용하기 위한 방안을 제시한다.

WEHI-231 cells are defective in the ligand-induced internalization of B cell antigen receptor

  • Yoon, Sang Soon;Kim, Tae Jin
    • IMMUNE NETWORK
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    • v.1 no.3
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    • pp.196-202
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    • 2001
  • Backgorund: WEHI-231 B cell line is a representative model for $IgM^+$ mature B cells. To understand the signaling differences between mature and immature B cells, we compared the responsiveness of WEHI-231 and Bal 17 B cell lines to BCR cross-linking. Methods: The extents of tyrosine phosphorylation, ligand-induced internalization, and activation-induced cell death upon BCR cross-linking were compared in two cell lines. Results: Despite a higher expression of BCR, cross-linking of BCR on WEHI-231 cell evoked a weaker level of tyrosine phosphorylation and BCR endocytosis than Bal 17 cells. Furthermore, the endocytosed BCR could not enter the lysosomal compartment and stayed as peripheral spots in WEHI-231 cells. Conclusion: WEHI-231 cell showed preferred BCR-mediated signaling pathways leading to a reduced capability of antigen presentation as well as the enhanced apoptosis in comparision with Bal 17 cells. These results might reflect the signaling differences between mature and immature B cells.

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Contour Parallel Offsetting and Tool-Path Linking Algorithm For Pocketing (포켓가공을 위한 오프셋 및 공구경로 연결 알고리즘)

  • Huh Jin-Hun;Kim Young-Yil;Jun Cha-Soo
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2003.05a
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    • pp.200-207
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    • 2003
  • Presented in this paper is a new fast and robust algorithm generating NC tool path for 2D pockets with islands. The input shapes are composed of line segments and cricular arcs. The algorithm has two steps: creation of successive offset loops and linking the loops to tool path. A modified pair-wise technique is developed in order to speed up and stabilize the offset process, and the linking algorithm is focused on minimizing tool retractions and preventing thin-wall rotting The proposed algorithm has been implemented In C++ and some illustrative examples are presented to show the practical strength of the algorithm.

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Expression of Neurotensin/Neuromedin N Precursor in Murine Mast Cells

  • Ahn, Hyun-Jong;Cho, Jeong-Je
    • The Korean Journal of Physiology and Pharmacology
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    • v.5 no.6
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    • pp.495-501
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    • 2001
  • We have cloned the mouse neurotensin/neuromedin N (NT/N) gene from the murine mast cell line Cl.MC/C57.1 for the first time. The murine NT/N cDNA clone consisted of 765 nucleotides and coded for 169 peptide residues with an N-terminal signal peptide, and the C-terminal region contained of one copy of neurotensin (NT) and one copy of neuromedin N (NN). Total of four Lys-Arg dibasic motifs were present; one each at the middle of the open reading frame, at the N-terminal of NN, at the C-terminal of NT, and between NN and NT. Amino acid sequence analysis of the mouse NT/N revealed 90% homology to that of the rat NT/N gene. NT/N is expressed in murine mast cell lines (Cl.MC/C57.1 and P815), but not in murine bone marrow-derived mast cells (BMMCs), murine macrophage cell line (RAW 264.7), nor in murine T cell line (EL-4). NT/N mRNA in C1.MC/C57.1 is highly inducible by IgE cross-linking, phorbol myristate acetate, neurotensin, and substance P. Following the treatment of demethylating agent, 5-azacytidine (5-azaC), the NT/N gene was induced in BMMCs in response to IgE cross-linking. 5-azaC-treated BMMCs did not express the NT/N gene without additional stimuli. These findings suggested that the regulation of NT/N gene expression was dependent on the effects of not only gene methylation but also enhancer and/or repressor proteins acting on the NT/N promoter.

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Estimation of Maximum Load Capacity at Interconnection Line of High-Speed and Conventional Line (기존선-고속선 연결선 구간에서 최대부하용량 평가)

  • Lee, Chang-Mu;Lee, Han-Min;Oh, Seo-Chan;Kim, Gil-Dong;Jang, Gil-Soo
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.1069-1070
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    • 2008
  • At the coupling area linking high speed line and conventional line, according to distance between trains due to speed limit of conventional line, the power load of substation supplying to this conventional line increase. At the coupling area between Kimcheon SS and Kyoungsan SS, train operation have problems caused by instantaneous voltage drop. So, this paper propose evaluation method of maximum load capacity at current normal feeding condition.

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