• 제목/요약/키워드: Correspondences

검색결과 156건 처리시간 0.029초

ITERATIVE FACTORIZATION APPROACH TO PROJECTIVE RECONSTRUCTION FROM UNCALIBRATED IMAGES WITH OCCLUSIONS

  • Shibusawa, Eijiro;Mitsuhashi, Wataru
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2009년도 IWAIT
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    • pp.737-741
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    • 2009
  • This paper addresses the factorization method to estimate the projective structure of a scene from feature (points) correspondences over images with occlusions. We propose both a column and a row space approaches to estimate the depth parameter using the subspace constraints. The projective depth parameters are estimated by maximizing projection onto the subspace based either on the Joint Projection matrix (JPM) or on the the Joint Structure matrix (JSM). We perform the maximization over significant observation and employ Tardif's Camera Basis Constraints (CBC) method for the matrix factorization, thus the missing data problem can be overcome. The depth estimation and the matrix factorization alternate until convergence is reached. Result of Experiments on both real and synthetic image sequences has confirmed the effectiveness of our proposed method.

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유방성 액정고분자계에 있어서 중간상의 분자배열 규칙성의 유변학적 해석 (Rheological Implications of mesomorphic Order in the Lyotropic Liquid Crystalline Polymer Systems)

  • 김병철
    • 유변학
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    • 제9권4호
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    • pp.200-205
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    • 1997
  • 등방상에서는 폴리파라페닐렌테레프탈아미드(PPD-T)와 히드록시 프로필 셀룰로오 스(HPC)가 비슷한 유변학적 거동을 보였다. 그러나 이방성에서는 네마틱상을 형성하는 PPD-T와 콜레스테릭상(또는 꼬인 네마틱상)을 형성하는 HPC는 상이한 유변학적 특성을 나타냈다. 이방상을 나타내는 임계농도(C*)이상의 농도에서 Herchel-Bulkey 모델에 의해 얻 어진 항복응력을 보면 HPC의 경우 농도에 관계없이 거의 일정한 값을 나타낸 반면PPD-T 의경우에는 농도증가와 더불어 항북응력값이 크게 증가하였다. 또한 PPD-T가 일\ulcorner거으로 HPC보다 큰값의 항복응력을 나타냈다. 진동수 1 rad/s 에서는 PPD-T와 HPCahen 탄성계 수 G'/2G"가 농도의 증가와 더불어 증가하엿다. 그러나 100rad/s 에서는 HPCdmlruddn 임계농도이상의 농도에서 농도증가와 더불어 탄성계수값이 단순감소한 반면 PPD-T의 경우 에는 포화농도(B-point)이상의 농도에서 농도증가와 더불어 탄성계수값이 계속적으로 증가 하였다. HPC의 경우 저장탄성률이 변형정도의 영향을 받지 않았으나 PPD-T의 경우에는 저장탄성률이 변형정도에 매우 민감하였다.

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튜링과 키에르케고어: 수학적 모델을 통한 이해 (Understanding Turing and Kierkegaard through a Mathematical Model)

  • 박창균
    • 한국수학사학회지
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    • 제27권2호
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    • pp.139-152
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    • 2014
  • This paper aims to compare and contrast Kierkegaard and Turing, whose birth dates were one hundred years apart, analyzing them from the perspective of the limit. The model of analysis is two concentric circles and movement in them and on the boundary of outer circle. In the model, Kierkegaard's existential stages have 1:1 correspondences: aesthetic stage, ethical stage, religious stage A and religious stage B correspond to inside of the inner circle, outside of the inner circle, the boundary of the outer circle and the outside of the outer circle, respectively. This paper claims that Turing belongs to inside of the outer circle and moves to the center while Kierkegaard belongs to outside of the outer circle and moves to the infinity. Both of them have movement of potential infinity but their directions are opposite.

곡선의 형태학적 성장과 변환의 제어 방법 (Control of Morphological Development and Transformation of Curves)

  • 이주행;박형준
    • 한국CDE학회논문집
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    • 제12권5호
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    • pp.354-365
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    • 2007
  • We present novel methods to generate a sequence of shapes that represents the pattern of morphological development or transformation of Bezier curves. The presented methods utilize the intrinsic geometric structures of a Bezier curve that are derived from rib and fan decomposition (RFD). Morphological development based on RFD shows a characteristic pattern of structural growth of a Bezier curve, which is the direct consequence of development path defined by fans. Morphological transformation based RFD utilizes development patterns of source and target curves to mimic the theory of evolutionary developmental biology: although the source and target curves are quite different in shapes, we can easily find similarities in their younger shapes, which makes it easier to set up feature correspondences for blending them. We also show that further controls on base transformation for intensity of feature blending, and extrapolation can compensate the immaturity of blended curves. We demonstrate the experimental results where transformation patterns are smoother and have unique geometric style that cannot be generated using conventional methods based on multi-linear blending.

Automatic Surface Matching for the Registration of LIDAR Data and MR Imagery

  • Habib, Ayman F.;Cheng, Rita W.T.;Kim, Eui-Myoung;Mitishita, Edson A.;Frayne, Richard;Ronsky, Janet L.
    • ETRI Journal
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    • 제28권2호
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    • pp.162-174
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    • 2006
  • Several photogrammetric and geographic information system applications such as surface matching, object recognition, city modeling, environmental monitoring, and change detection deal with multiple versions of the same surface that have been derived from different sources and/or at different times. Surface registration is a necessary procedure prior to the manipulation of these 3D datasets. This need is also applicable in the field of medical imaging, where imaging modalities such as magnetic resonance imaging (MRI) can provide temporal 3D imagery for monitoring disease progression. This paper will present a general automated surface registration procedure that can establish correspondences between conjugate surface elements. Experimental results using light detection and ranging (LIDAR) and MRI data will verify the feasibility, robustness, and accuracy of this approach.

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RANSAC 방법을 이용한 항공 사진 모자이킹 기법 (Mosaicking Techniques of Aerial Photographs using the RANSAC Algorithm)

  • 임인근
    • 한국군사과학기술학회지
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    • 제10권2호
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    • pp.180-187
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    • 2007
  • In this paper, we propose an automatic method which combines two or more images acquired by camera on the air-vehicle into a larger image mosaics. The shift, scaling, rotation factors between two images can be calculated by using the correspondences between the points of the images. In order to estimate these factors, we find the relative positions of two images with respect to each other by using the SIFT descriptor and the RANSAC algorithm. After estimating the factors, the images can be merged into a single image mosaic by warping the target image. To avoid seams when mosaics are constructed from overlapped images, we apply the average gray level value of points within a overlapped zone. We have tested our proposed method on various image sets and have confirmed that our method produced good result subjectively.

TRIZ를 활용한 유아 및 노약자를 위한 안전감지시스템 개발에 관한 연구 (A Study on Development of Security Detection System for Infant, the Old and the Weak by using TRIZ)

  • 이국환;이경원
    • 반도체디스플레이기술학회지
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    • 제7권1호
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    • pp.59-65
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    • 2008
  • There are no products, systems to manage health and detect security for infant, the old and the weak in Korea. Recently, the concerns of parents are increasing more about all of children(baby, infant, etc) because rate of birth is decreasing gradually. Also, the average span of human life is on an increasing trend according to well-being and evolution of medical treatment. Therefore, this treatise analyzed problems in managing and following-up infant, the old and the weak at present. By using TRIZ to solve problems, we devised new conceptional ideas, detail designs to manage health, detect security, cope with correspondences for them and developed the prototype and tested it. Excellent performances are proved through various field test.

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실내 주행을 위한 3차원 장애물 검출 (Three Dimensional Obstacle Detection for Indoor Navigation)

  • 고복경;우동민
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 B
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    • pp.1251-1253
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    • 1996
  • The vision processing system for mobile robots requires real time processing and reliability for the purpose of safe navigation. But, general types of vision systems are not appropriate owing to the correspondence problem which correlates the points out of two images. To determine the obstacle area, we use correspondences of line segments between two perspective images sequentially acquired by camera. To simplify the correspondence, the matching of line segments are performed in the navigation space, based on the assumption that mobile robot should be navigated in the flat surface and the motion of mobile robot between two frames should be approximately known.

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Panoramic Image Stitching using SURF

  • You, Meng;Lim, Jong-Seok;Kim, Wook-Hyun
    • 융합신호처리학회논문지
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    • 제12권1호
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    • pp.26-32
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    • 2011
  • This paper proposes a new method to process panoramic image stitching using SURF(Speeded Up Robust Features). Panoramic image stitching is considered a problem of the correspondence matching. In computer vision, it is difficult to find corresponding points in variable environment where a scale, rotation, view point and illumination are changed. However, SURF algorithm have been widely used to solve the problem of the correspondence matching because it is faster than SIFT(Scale Invariant Feature Transform). In this work, we also describe an efficient approach to decreasing computation time through the homography estimation using RANSAC(random sample consensus). RANSAC is a robust estimation procedure that uses a minimal set of randomly sampled correspondences to estimate image transformation parameters. Experimental results show that our method is robust to rotation, zoom, Gaussian noise and illumination change of the input images and computation time is greatly reduced.

고해상 3차원 PTV에 의한 돌발분류구조 계측 (Measurement of a Pulsed Jet with High-Definition 3D-PTV)

  • 도덕희;황태규;조용범;편용범
    • 한국가시화정보학회:학술대회논문집
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    • 한국가시화정보학회 2002년도 추계학술대회 논문집
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    • pp.43-44
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    • 2002
  • A pulsed jet was measured with high-definition 3D-PTV technique. The measurement system consists of three CCD cameras, Ar-ion laser, an image grabber and a host computer. Two fitness functions were introduced in a genetic algorithm in order to enhance the correspondences of the particles. One was based on a concept of the continuum theory and the other one was based on a minimum distance error. The head vortex of the jet was visualized by LIF and was reconstructed by the constructed high-resolution 30-PTV system for comparisons.

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