• Title/Summary/Keyword: Line Segments

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Segmentation of Digital Curves by Structural Analysis (구조해석에 의한 디지털 곡선의 분리)

  • 류승필;권오석;김태균
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.12
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    • pp.1984-1994
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    • 1989
  • Techniques for approximating digitalcurves by polygonal lines are a valuable tool for image analysis and data compression. S. Shilien proposed a method for segmenting a digital curve into digital straight line segments digital straight line segments which are not satisfied with the structural properties, and have more than one break point by Shilien's method. Here, the structural representation of digital straight lines and digital staight line segments is described. And a method for segmenting a digital curve into digital straight line segments which are not satisfied with the structural properties, and have more than one break point by Shilien's method. Here, the structural representation of digital straight lines and digital staight line segments is described. And a method for segmenting a digital curve into digital straight line segments which may be not satisfied with the structural properties is proposed. The number of break points extracted by this method is less than that by S. Shilien's method from the digital curve which includes the digital straight line segments not satisfied with the structural properties.

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Using the obstacle position information of the mobile robot in the two-dimensional cartography Study (장애물 위치 정보를 이용한 모바일 로봇의 2차원 지도 작성에 관한 연구)

  • Lee, Jun-Ho;Hong, Hyun-Ju;Kang, Seog-Joo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.13 no.1
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    • pp.30-38
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    • 2014
  • The purpose of this study is to build and manage environment models with line segments from sonar range data on obstacles in unknown and varied environments. The proposed method therefore employs a two-stage data-transform process in order to extract environmental line segments from range data on obstacles. In the first stage, the occupancy grid extracted from the range data is accumulated to form a two-dimensional local histogram grid. In the second stage, a line histogram extracted from a local histogram grid is based on a Hough transform, and matching serves as a means of comparing each of the segments on a global line segments map against the line segments to detect the degree of similarity in the overlap, orientation, and arrangement. Each of these tests is formulated by comparing one of the parameters in the segment representation. After the tests, new line segments can be found at maximum-density cells in the line histogram, and they are composed onto the global line segment map. The proposed technique is demonstrated in experiments in an indoor environment.

Localization for Mobile Robot Using Line Segments (라인 세그먼트를 이용한 이동 로봇의 자기 위치 추정)

  • 강창훈;안현식
    • Proceedings of the IEEK Conference
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    • 2003.07c
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    • pp.2581-2584
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    • 2003
  • In this paper, we propose a self-localization algorithm using vertical line segments. Indoor environment is consist of horizontal and vertical line features such as doors, furniture, and so on. From the input image, vertical line edges are detected by an edge operator, Then, line segments are obtained by projecting edge image vertically and detecting local maximum from the projected histogram. From the relation of horizontal position of line segments and the location of the robot, nonlinear equations are come out Localization is done by solving the equations by using Newton's method. Experimental results show that the proposed algorithm using one camera is simple and applicable to indoor environment.

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Hypothesis Tests For Performances of a New Spline Interpolation Technique (신 스플라인보간법의 퍼포먼스 가설점정)

  • Yu, Ki-Yun
    • Journal of Korean Society for Geospatial Information Science
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    • v.7 no.1 s.13
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    • pp.29-40
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    • 1999
  • In vector GIS, natural linear entities (called linear entitles) are usually represented by a set of line segments. As an alternative of the line segments, curve segments can be used to represent the linear entities. The curve segments, as one-dimensional spatial objects, we generated by spline interpolation technique such as Bezier technique. In an effort to improve its accuracy in resembling the linear entities, the Bezier technique was modified generating a new technique (called New technique) (Kiyun, 1998). In this paper, validity of the New technique was tested. Test focused on answering two questions: (1) whether or not the curve segments from the New technique replace line segments so as to enhance the accuracy of representations of linear entities, and (2) whether or not the curve segments from the New technique represent the linear entities more accurately than curve segments from the Bezier technique. Answering these two questions entailed two hypothesis tests. For test data, a series of hydrologic lines on 7.5-minute USGS map series were selected. Test were done using t-test method and statistical inferences were made from the results. Test results indicated that curve segments from both the Bezier and New techniques represent the linear entities more accurately than the line segments do. In addition, curve segments from the New technique represent the linear entities more accurately than the line segments from the Bezier technique do at probability level 69% or higher.

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Line Segments Map Building Using Sonar for Mobile Robot (초음파 센서를 이용한 이동 로봇의 직선선분 지도 작성)

  • Hong, Hyeon-Ju;Gwon, Seok-Geun;No, Yeong-Sik
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.9
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    • pp.783-789
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    • 2001
  • The purpose of this study is to build and to manage environment models with line segments from the sonar range data on obstacles in unknown and varied environments. The proposed method subsequently employs a two-stage data-transform process in order to extract environmental line segments from the range data on obstacles. In the first stage, the occupancy grid extracted from the range data is accumulated to a two-dimensional local histogram grid. In the second stage, a line histogram extracted from an local histogram gird is based on a Hough transform, and matching is a process of comparing each of the segments in the global line segments map against the line segments to detect similarity in overlap, orientation, and arrangement. Each of these tests is made by comparing one of the parameters in the segment representation. After the tests, new line segments are composed to the global line segments map. The proposed technique is illustrated by experiments in an indoor environment.

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Line Segments Extraction by using Chain Code Tracking of Edge Map from Aerial Images (항공영상으로부터 에지 맵의 체인코드 추적에 의한 선소추출)

  • Lee Kyu-won;Woo Dong-min
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.6
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    • pp.709-713
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    • 2005
  • A new algorithm is proposed for the extraction of line segments to construct 3D wire-frame models of building from the high-resolution aerial images. The purpose of this study Is the accurate and effective extraction of line segments, considering the problems such as discordance of lines and blurred edges existing in the conventional methods. Using the edge map extracted from aerial images, chain code tracking of edges was performed. Then, we extract the line segments considering the strength of edges and the direction of them. SUSAN (Smallest Uni-value Segment Assimilating Nucleus) algorithm proposed by Smith was used to extract an edge map. The proposed algorithm consists of 4 steps: removal of the horizontal, vertical and diagonal components of edges to reduce non-candidate point of line segments based on the chain code tracking of the edge map, removal of contiguous points, removal of the same angle points, and the extraction of the start and end points to be line segments. By comparing the proposed algorithm with Boldt algorithm, better results were obtained regarding the extraction of the representative line segments of buildings, having relatively less extraction of unnecessary line segments.

Waveform Detection Algorithm based on the Search of Distinctive Line-Segments (검색에 기초한 파형 검출 알고리듬)

  • 박승훈;장태규
    • Journal of Biomedical Engineering Research
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    • v.14 no.3
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    • pp.265-272
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    • 1993
  • We present a new waveform detection method, based on the search of distinctive line-segments. The method is based on the basic assumption that the waveform morphology of biological signals is readily characterized by a sequence of the distinctive line-segments and their structural features. In this method, the distinctive line-segments are first searched for, and a structural feature analysis is performed an the distinctive line-segments found. Experiments of detecting epileptic spikes were carried out to evaluate the detection per formance of the method. Two subjects were used for training and tuning the algorithm and four subjects for testing the method. The results were obtained on two different performance indices, detection ratio and the number of false detections per minute.

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Elementary School Students' Mathematical Metaphors for Line Segments, Straight Lines, and Rays

  • Sangmee Kim
    • Research in Mathematical Education
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    • v.26 no.4
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    • pp.271-289
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    • 2023
  • This research investigates the development of elementary students' concepts of line segments, straight lines, and rays, employing metaphor analysis as a research methodology. By analyzing metaphorical expressions, the research aims to explore how elementary students form these geometric concepts line segments, straight lines, and lays and evolve their understanding of them across different grades. Surveys were conducted with elementary school students in grades three to six, focusing on metaphorical expressions and corresponding their reasons associated with line segments, straight lines, and rays. The data were analyzed through coding and categorization to identify the types in students' metaphorical expressions. The analysis of metaphorical expressions identified five types: straightness, infinity or direction, connections of another geometric concepts, shape and symbols, and terminology.

Single-View Reconstruction of a Manhattan World from Line Segments

  • Lee, Suwon;Seo, Yong-Ho
    • International journal of advanced smart convergence
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    • v.11 no.1
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    • pp.1-10
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    • 2022
  • Single-view reconstruction (SVR) is a fundamental method in computer vision. Often used for reconstructing human-made environments, the Manhattan world assumption presumes that planes in the real world exist in mutually orthogonal directions. Accordingly, this paper addresses an automatic SVR algorithm for Manhattan worlds. A method for estimating the directions of planes using graph-cut optimization is proposed. After segmenting an image from extracted line segments, the data cost function and smoothness cost function for graph-cut optimization are defined by considering the directions of the line segments and neighborhood segments. Furthermore, segments with the same depths are grouped during a depth-estimation step using a minimum spanning tree algorithm with the proposed weights. Experimental results demonstrate that, unlike previous methods, the proposed method can identify complex Manhattan structures of indoor and outdoor scenes and provide the exact boundaries and intersections of planes.

EEG WAVEFORM DETECTION BASED ON THE SEARCH OF DISTINCTIVE LINE-SEGMENTS (특징적인 직선요소들의 검색에 기초한 EEG 파형 검출)

  • Park, Seung-Hun;Chang, Tae-Kyu
    • Proceedings of the KOSOMBE Conference
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    • v.1992 no.05
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    • pp.121-122
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    • 1992
  • We present a new EEG waveform detection method, based on the search of distinctive line-segments. The method is based on the assumption that EEG waveform morphology is characterized by a sequence of its distinctive line-segments and their structural features. In this method, the distinctive line segments are first searched for, and the structural feature analysis is performed on the found line-segment sequence. Experiments of detecting epileptic spikes are performed on four different subjects.

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