• 제목/요약/키워드: Point correspondence

검색결과 138건 처리시간 0.05초

ICP 계산속도 향상을 위한 빠른 Correspondence 매칭 방법 (A Fast Correspondence Matching for Iterative Closest Point Algorithm)

  • 신건희;최재희;김광기
    • 로봇학회논문지
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    • 제17권3호
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    • pp.373-380
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    • 2022
  • This paper considers a method of fast correspondence matching for iterative closest point (ICP) algorithm. In robotics, the ICP algorithm and its variants have been widely used for pose estimation by finding the translation and rotation that best align two point clouds. In computational perspectives, the main difficulty is to find the correspondence point on the reference point cloud to each observed point. Jump-table-based correspondence matching is one of the methods for reducing computation time. This paper proposes a method that corrects errors in an existing jump-table-based correspondence matching algorithm. The criterion activating the use of jump-table is modified so that the correspondence matching can be applied to the situations, such as point-cloud registration problems with highly curved surfaces, for which the existing correspondence-matching method is non-applicable. For demonstration, both hardware and simulation experiments are performed. In a hardware experiment using Hokuyo-10LX LiDAR sensor, our new algorithm shows 100% correspondence matching accuracy and 88% decrease in computation time. Using the F1TENTH simulator, the proposed algorithm is tested for an autonomous driving scenario with 2D range-bearing point cloud data and also shows 100% correspondence matching accuracy.

A study on correspondence problem of stereo vision system using self-organized neural network

  • 조영빈;권대갑
    • 한국정밀공학회지
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    • 제10권4호
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    • pp.170-179
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    • 1993
  • In this study, self-organized neural network is used to solve the vorrespondence problem of the axial stereo image. Edge points are extracted from a pair of stereo images and then the edge points of rear image are assined to the output nodes of neural network. In the matching process, the two input nodes of neural networks are supplied with the coordi- nates of the edge point selected randomly from the front image. This input data activate optimal output node and its neighbor nodes whose coordinates are thought to be correspondence point for the present input data, and then their weights are allowed to updated. After several iterations of updating, the weights whose coordinates represent rear edge point are converged to the coordinates of the correspondence points in the front image. Because of the feature map properties of self-organized neural network, noise-free and smoothed depth data can be achieved.

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Dynamic Simple Correspondence Analysis

  • Choi Yong-Seok;Hyun Gee Hong;Seo Myung Rok
    • Communications for Statistical Applications and Methods
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    • 제12권1호
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    • pp.199-205
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    • 2005
  • In general, simple correspondence analysis has handled mainly correspondence relations between the row and column categories but can not display the trends of their change over the time. For solving this problem, we will propose DSCA(Dynamic Simple Correspondence Analysis) of transition matrix data using supplementary categories in this study, Moreover, DSCA provides its trend of the change for the future by predicting and displaying trend toward the change from a standard point of time to the next.

학교급식 영양사의 서비스 리더십이 조리종사원의 태도에 미치는 영향 (A Study on the Influence of Dietitians' Service Leadership on School Foodservice Employees' Attitudes)

  • 손대래;김현아
    • 대한영양사협회학술지
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    • 제15권3호
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    • pp.298-310
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    • 2009
  • The purposes of this study were to examine school foodservice employees' awareness on dietitians' service leadership and to analyze the effects of the service leadership on employee attitudes (leader reliability, value correspondence, and leader satisfaction). Questionnaires were distributed to 208 school foodservice employees from November 2007 to January 2008. The results were as follows. First, in terms of the employees' perception on the dietitians' service leadership, service belief gained the highest score, followed by insight, attitude, and ability: the average score was 3.8 point. Second, the leader reliability and leader satisfaction scores perceived by the employees were over 3.8 point on average but the awareness on the value correspondence was 3.43 point. Third, among the service leadership factors, service belief (p<0.001) and insight (p<0.001) had positive effects on leader reliability. Also, service belief (p<0.01), service ability (p<0.001), and insight (p<0.01) had positive effects on value correspondence. Finally, service belief (p<0.001), service ability (p<0.05), and insight (p<0.001) had positive effects on leader satisfaction. Fourth, a hypothesis test using path analysis revealed that dietitians' service leadership produced positive effects on school foodservice employees' attitudes (leader reliability, value correspondence, and leader satisfaction). In conclusion, the service leadership of dietitians directly contributed to leader satisfaction, value correspondence, and leader reliability in school foodservice employees.

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수치정사사진을 이용한 지적불부합지 조사 방법의 개선 (An Improvement of Cadastral Non-coincidence Surveying Method using Digital Orthophoto)

  • 홍성언
    • 대한공간정보학회지
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    • 제14권2호
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    • pp.23-32
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    • 2006
  • 본 연구에서는 기존 수치정사사진을 이용한 지적불부합지 조사에 있어 육안판독 수준의 문제를 개선하고자 기존 조사 방법보다 신속하고 객관적으로 불부합지를 조사할 수 있는 새로운 방법론을 제시하고자 하였다. 이를 위해 적용 가능한 방법론을 탐색하고 적용 방법을 정립하였다. 이렇게 정립된 방법론을 이용하여 프로토타입 시스템을 구현하였다. 그리고 실제 실험지역 적용을 통하여 방법론의 적용 가능성을 제시하고자 하였다. 연구 성과로는 기존 조사 방법보다 객관적이고 효율적으로 조사할 수 있는 point-correspondence 기반의 불부합지 조사 방법을 제시하였다. 정확도 측면의 타당성을 제시하고자 동일한 지역을 대상으로 기존 조사 기법과 비교한 결과 정확도 면에서 많은 차이를 보이지 않아 방법론의 적용 가능성을 제시할 수 있었다.

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시각 서보 제어에 있어서 대응점 선택 알고리즘 개발 (Development of a Correspondence Point Selection Algorithm for Visual Servo Control)

  • 문용선;정남채
    • 한국음향학회지
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    • 제18권2호
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    • pp.66-76
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    • 1999
  • 본 논문은 스테레오 카메라를 대응점 문제가 발생하지 않을 만큼 병진 및 전진 이동시켜 고속으로 양안 시차 정보를 획득할 수 있다는 것을 제안한다. 병진 이동하는 스테레오 비전에 있어서 오차가 없고 신뢰성이 높은 시차 정보를 획득할 수 있다는 것과 전진 이동하는 스테레오 비전에 있어서는 통상의 스테레오 비전으로는 검출할 수 없는 수평성분을 획득할 수 있다는 것을 나타낸다. 또한 좌우 화상사이의 대응을 미리 한정하기 때문에 한정하지 않을 때에 비해 대응점이 밝고 작게 되므로 고속으로 스테레오 비전을 행할 수 있다. 그러나 전진 이동하는 스테레오 비전에 있어서 화상중심 부근과 폐색영역이 일치하면 바른 양안 시차 정보를 얻을 수 없는 문제가 있다.

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Temporal Search Algorithm for Multiple-Pedestrian Tracking

  • Yu, Hye-Yeon;Kim, Young-Nam;Kim, Moon-Hyun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권5호
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    • pp.2310-2325
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    • 2016
  • In this paper, we provide a trajectory-generation algorithm that can identify pedestrians in real time. Typically, the contours for the extraction of pedestrians from the foreground of images are not clear due to factors including brightness and shade; furthermore, pedestrians move in different directions and interact with each other. These issues mean that the identification of pedestrians and the generation of trajectories are somewhat difficult. We propose a new method for trajectory generation regarding multiple pedestrians. The first stage of the method distinguishes between those pedestrian-blob situations that need to be merged and those that require splitting, followed by the use of trained decision trees to separate the pedestrians. The second stage generates the trajectories of each pedestrian by using the point-correspondence method; however, we introduce a new point-correspondence algorithm for which the A* search method has been modified. By using fuzzy membership functions, a heuristic evaluation of the correspondence between the blobs was also conducted. The proposed method was implemented and tested with the PETS 2009 dataset to show an effective multiple-pedestrian-tracking capability in a pedestrian-interaction environment.

GALOIS CORRESPONDENCES FOR SUBFACTORS RELATED TO NORMAL SUBGROUPS

  • Lee, Jung-Rye
    • 대한수학회논문집
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    • 제17권2호
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    • pp.253-260
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    • 2002
  • For an outer action $\alpha$ of a finite group G on a factor M, it was proved that H is a, normal subgroup of G if and only if there exists a finite group F and an outer action $\beta$ of F on the crossed product algebra M $\times$$_{\alpha}$ G = (M $\times$$_{\alpha}$ F. We generalize this to infinite group actions. For an outer action $\alpha$ of a discrete group, we obtain a Galois correspondence for crossed product algebras related to normal subgroups. When $\alpha$ satisfies a certain condition, we also obtain a Galois correspondence for fixed point algebras. Furthermore, for a minimal action $\alpha$ of a compact group G and a closed normal subgroup H, we prove $M^{G}$ = ( $M^{H}$)$^{{beta}(G/H)}$for a minimal action $\beta$ of G/H on $M^{H}$.f G/H on $M^{H}$.TEX> H/.

RANSAC에 기초한 화면내 평면 영역 샘플링에 의한 스테레오 화상의 대응 매칭 (Correspondence Matching of Stereo Images by Sampling of Planar Region in the Scene Based on RANSAC)

  • 정남채
    • 융합신호처리학회논문지
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    • 제12권4호
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    • pp.242-249
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    • 2011
  • 화면 내의 평면영역에서 투영변환행렬 대응 매칭법을 제안한다. 본 연구는 RANSAC에 있지만, RANSAC에서 랜덤 샘플링에 균일분포를 이용하는 것아 아니고, 화상의 특징점 위치나 템플리트 매칭의 차이로부터 구한 다중의 비균일 분포를 이용한다. 기존의 매칭법은 정대응이 거의 만족해야 할 조건을 이용하여 올바르다고 추정되는 대응을 샘플링하고, 그 대응을 1대 1로 매칭시켜 RANSAC을 행하였지만, 제안 방법에서는 화상으로부터 구한 다중의 확률 분포에서 단계적으로 샘플링함으로써 확률이 높은 정대응을 다중의 대응 후보 중에서 효율적으로 샘플링할 수 있다. 그 결과 최종적으로 수많은 정대응을 구할 수 있으며, 시뮬레이션과 실제 화상의 실험에 의하여 제안 방법의 유효성을 검증한다.

Registration of Aerial Image with Lines using RANSAC Algorithm

  • Ahn, Y.;Shin, S.;Schenk, T.;Cho, W.
    • 한국측량학회지
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    • 제25권6_1호
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    • pp.529-536
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    • 2007
  • Registration between image and object space is a fundamental step in photogrammetry and computer vision. Along with rapid development of sensors - multi/hyper spectral sensor, laser scanning sensor, radar sensor etc., the needs for registration between different sensors are ever increasing. There are two important considerations on different sensor registration. They are sensor invariant feature extraction and correspondence between them. Since point to point correspondence does not exist in image and laser scanning data, it is necessary to have higher entities for extraction and correspondence. This leads to modify first, existing mathematical and geometrical model which was suitable for point measurement to line measurements, second, matching scheme. In this research, linear feature is selected for sensor invariant features and matching entity. Linear features are incorporated into mathematical equation in the form of extended collinearity equation for registration problem known as photo resection which calculates exterior orientation parameters. The other emphasis is on the scheme of finding matched entities in the aide of RANSAC (RANdom SAmple Consensus) in the absence of correspondences. To relieve computational load which is a common problem in sampling theorem, deterministic sampling technique and selecting 4 line features from 4 sectors are applied.