• Title/Summary/Keyword: Correspondence detection

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An Identification of Outlying Cells in Contingency Table via Correspondence Analysis Map

  • Hong, Chong Sun;Lee, Jong Cheol
    • Communications for Statistical Applications and Methods
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    • v.8 no.1
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    • pp.39-49
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    • 2001
  • When an appropriate model is fitted to explain a certain categorical data, outlying cell detection plays very important role to reduce the lack of fit. There exist many statistical methods to identify outlying cells in contingency table. In this paper, correspondence analysis is applied to identify one or two outlying cells. When corresponding relationships between categories of the row and columns are explored, we find that outlying cells could be identified via the correspondence analysis map.

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Efficient and Robust Correspondence Detection between Unbalanced Stereo Images

  • Kim, Yong-Ho;Kim, Jong-Su;Lee, Sangkeun;Choi, Jong-Soo
    • IEIE Transactions on Smart Processing and Computing
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    • v.1 no.3
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    • pp.161-170
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    • 2012
  • This paper presents an efficient and robust approach for determining the correspondence between unbalanced stereo images. The disparity vectors were used instead of feature points, such as corners, to calculate a correspondence relationship. For a faster and optimal estimation, the vectors were classified into several regions, and the homography of each region was calculated using the RANSAC algorithm. The correspondence image was calculated from the images transformed by each homography. Although it provided good results under normal conditions, it was difficult to obtain reliable results in an unbalanced stereo pair. Therefore, a balancing method is also proposed to minimize the unbalance effects using the histogram specification and structural similarity index. The experimental results showed that the proposed approach outperformed the baseline algorithms with respect to the speed and peak-signal-to-noise ratio. This work can be applied to practical fields including 3D depth map acquisition, fast stereo coding, 2D-to-3D conversion, etc.

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Recognizing Static Target in Video Frames Taken from Moving Platform

  • Wang, Xin;Sugisaka, Masanori;Xu, Wenli
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.673-676
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    • 2003
  • This paper deals with the problem of moving object detection and location in computer vision. We describe a new object-dependent motion analysis method for tracking target in an image sequence taken from a moving platform. We tackle these tasks with three steps. First, we make an active contour model of a target in order to build some of low-energy points, which are called kernels. Then we detect interest points in two windows called tracking windows around a kernel respectively. At the third step, we decide the correspondence of those detected interest points between tracking windows by the probabilistic relaxation method In this algorithm, the detecting process is iterative and begins with the detection of all potential correspondence pair in consecutive image. Each pair of corresponding points is then iteratively recomputed to get a globally optimum set of pairwise correspondences.

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An Obstacle Detection and Avoidance Method for Mobile Robot Using a Stereo Camera Combined with a Laser Slit

  • Kim, Chul-Ho;Lee, Tai-Gun;Park, Sung-Kee;Kim, Jai-Hie
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.871-875
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    • 2003
  • To detect and avoid obstacles is one of the important tasks of mobile navigation. In a real environment, when a mobile robot encounters dynamic obstacles, it is required to simultaneously detect and avoid obstacles for its body safely. In previous vision system, mobile robot has used it as either a passive sensor or an active sensor. This paper proposes a new obstacle detection algorithm that uses a stereo camera as both a passive sensor and an active sensor. Our system estimates the distances from obstacles by both passive-correspondence and active-correspondence using laser slit. The system operates in three steps. First, a far-off obstacle is detected by the disparity from stereo correspondence. Next, a close obstacle is acquired from laser slit beam projected in the same stereo image. Finally, we implement obstacle avoidance algorithm, adopting the modified Dynamic Window Approach (DWA), by using the acquired the obstacle's distance.

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A Study on the TWS Tracking Filter for Multi-Target Tracking (다중표적 추적을 위한 TWS추적필터에 관한 연구)

  • 이양원;서진헌;이장규
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.41 no.4
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    • pp.411-421
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    • 1992
  • In the conventional track while scan (TWS) system, there are two major functions to be performed : detection and tracking. These two functions are normally designed and optimised independently. So TWS algorithm ignores the available decision features that can help in resolving the plot-to-track association ambiguity. Therefore conventional TWS system cna't track the targets in a densed multi-target environment. This paper presents a new TWS algorithm for multi-target track to solve the existing TWS system problem in clutter environment. The algorithm proposed in this paper is derived by modifying the part of joint probabilistic data association (JPDA) algotithm to get the one to one correspondence instead of multiple correspondence and combined with maneuvering detection logic so that it could also track the low maneuvering targets. Simulations to confirm the performance are done in crossing, parallel and maneuvering target. The proposed algorithm was successfully tracking targets above target situations.

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A binocular robot vision system with quadrangle recognition

  • Yabuta, Yoshito;Mizumoto, Hiroshi;Arii, Shiro
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.80-83
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    • 2005
  • A binocular robot vision system having an autonomously moving active viewpoint is proposed. By using this active viewpoint, the system constructs a correspondence between the images of a feature points on the right and left retinas and calculates the spatial coordinates of the feature points. The system incorporates a function of detecting straight lines in an image. To detect lines the system uses Hough transform. The system searches a region surrounded by 4 straight lines. Then the system recognizes the region as a quadrangle. The system constructs a correspondence between the quadrangles in the right and left images. By the use of the result of the constructed correspondence, the system calculates the spatial coordinates of an object. An experiment shows the effect of the line detection using Hough transform, the recognition of the surface of the object and the calculation of the spatial coordinates of the object.

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Improvement of Building Region Correspondence between SLI and Vector Map Based on Region Splitting (영역분할에 의한 SLI와 벡터 지도 간의 건물영역 일치도 향상)

  • Lee, Jeong Ho;Ga, Chill O;Kim, Yong Il;Yu, Ki Yun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.30 no.4
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    • pp.405-412
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    • 2012
  • After the spatial discrepancy between SLI(Street-Level Imagery) and vector map is removed by their conflation, the corresponding building regions can be found based on SLI parameters. The building region correspondence, however, is not perfect even after the conflation. This paper aims to improve the correspondence of building regions by region splitting of an SLI. Regions are initialized by the seed lines, projection of building objects onto SLI scene. First, sky images are generated by filtering, segmentation, and sky region detection. Candidates for split lines are detected by edge detector, and then images are splitted into building regions by optimal split lines based on color difference and sky existence. The experiments demonstrated that the proposed region splitting method had improved the accuracy of building region correspondence from 83.3% to 89.7%. The result can be utilized effectively for enhancement of SLI services.

Precise Geometric Registration of Aerial Imagery and LIDAR Data

  • Choi, Kyoung-Ah;Hong, Ju-Seok;Lee, Im-Pyeong
    • ETRI Journal
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    • v.33 no.4
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    • pp.506-516
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    • 2011
  • In this paper, we develop a registration method to eliminate the geometric inconsistency between the stereo-images and light detection and ranging (LIDAR) data obtained by an airborne multisensor system. This method consists of three steps: registration primitive extraction, correspondence establishment, and exterior orientation parameter (EOP) adjustment. As the primitives, we employ object points and linked edges from the stereo-images and planar patches and intersection edges from the LIDAR data. After extracting these primitives, we establish the correspondence between them, being classified into vertical and horizontal groups. These corresponding pairs are simultaneously incorporated as stochastic constraints into aerial triangulation based on the bundle block adjustment. Finally, the EOPs of the images are adjusted to minimize the inconsistency. The results from the application of our method to real data demonstrate that the inconsistency between both data sets is significantly reduced from the range of 0.5 m to 2 m to less than 0.05 m. Hence, the results show that the proposed method is useful for the data fusion of aerial images and LIDAR data.

False Alarm Minimization Technology using SVM in Intrusion Prevention System (SVM을 이용한 침입방지시스템 오경보 최소화 기법)

  • Kim Gill-Han;Lee Hyung-Woo
    • Journal of Internet Computing and Services
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    • v.7 no.3
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    • pp.119-132
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    • 2006
  • The network based security techniques well-known until now have week points to be passive in attacks and susceptible to roundabout attacks so that the misuse detection based intrusion prevention system which enables positive correspondence to the attacks of inline mode are used widely. But because the Misuse detection based Intrusion prevention system is proportional to the detection rules, it causes excessive false alarm and is linked to wrong correspondence which prevents the regular network flow and is insufficient to detect transformed attacks, This study suggests an Intrusion prevention system which uses Support Vector machines(hereinafter referred to as SVM) as one of rule based Intrusion prevention system and Anomaly System in order to supplement these problems, When this compared with existing intrusion prevention system, show performance result that improve about 20% and could through intrusion prevention system that propose false positive minimize and know that can detect effectively about new variant attack.

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