• 제목/요약/키워드: Matching error

검색결과 754건 처리시간 0.037초

연속 항공영상에서의 Image Registration (Image Registration of Aerial Image Sequences)

  • 강민석;김준식;박래홍;이쾌희
    • 전자공학회논문지B
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    • 제29B권4호
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    • pp.48-57
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    • 1992
  • This paper addresses the estimation of the shift vector from aerial image sequences. The conventional feature-based and area-based matching methods are simulated for determining the suitable image registration scheme. Computer simulations show that the feature-based matching schemes based on the co-occurrence matrix, autoregressive model, and edge information do not give a reliable matching for aerial image sequences which do not have a suitable statistical model or significant features. In area-based matching methods we try various similarity functions for a matching measure and discuss the factors determining the matching accuracy. To reduce the estimation error of the shift vector we propose the reference window selection scheme. We also discuss the performance of the proposed algorithm based on the simulation results.

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A XML Schema Matching based on Fuzzy Similarity Measure

  • Kim, Chang-Suk;Sim, Kwee-Bo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.1482-1485
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    • 2005
  • An equivalent schema matching among several different source schemas is very important for information integration or mining on the XML based World Wide Web. Finding most similar source schema corresponding mediated schema is a major bottleneck because of the arbitrary nesting property and hierarchical structures of XML DTD schemas. It is complex and both very labor intensive and error prune job. In this paper, we present the first complex matching of XML schema, i.e. XML DTD, inlining two dimensional DTD graph into flat feature values. The proposed method captures not only schematic information but also integrity constraints information of DTD to match different structured DTD. We show the integrity constraints based hierarchical schema matching is more semantic than the schema matching only to use schematic information and stored data.

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Local stereo matching using combined matching cost and adaptive cost aggregation

  • Zhu, Shiping;Li, Zheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권1호
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    • pp.224-241
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    • 2015
  • Multiview plus depth (MVD) videos are widely used in free-viewpoint TV systems. The best-known technique to determine depth information is based on stereo vision. In this paper, we propose a novel local stereo matching algorithm which is radiometric invariant. The key idea is to use a combined matching cost of intensity and gradient based similarity measure. In addition, we realize an adaptive cost aggregation scheme by constructing an adaptive support window for each pixel, which can solve the boundary and low texture problems. In the disparity refinement process, we propose a four-step post-processing technique to handle outliers and occlusions. Moreover, we conduct stereo reconstruction tests to verify the performance of the algorithm more intuitively. Experimental results show that the proposed method is effective and robust against local radiometric distortion. It has an average error of 5.93% on the Middlebury benchmark and is compatible to the state-of-art local methods.

A XML DTD Matching using Fuzzy Similarity Measure

  • Kim, Chang-Suk;Son, Dong-Cheul;Kim, Dae-Su
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제3권1호
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    • pp.32-36
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    • 2003
  • An equivalent schema matching among several different source schemas is very important for information integration or mining on the XML based World Wide Web. Finding most similar source schema corresponding mediated schema is a major bottleneck because of the arbitrary nesting property and hierarchical structures of XML DTD schemas. It is complex and both very labor intensive and error prune job. In this paper, we present the first complex matching of XML schema, i.e. XML DTD. The proposed method captures not only schematic information but also integrity constraints information of DTD to match different structured DTD. We show the integrity constraints based hierarchical schema matching is more semantic than the schema matching only to use schematic information and stored data.

Reference Priors in a Two-Way Mixed-Effects Analysis of Variance Model

  • 장인홍;김병휘
    • Journal of the Korean Data and Information Science Society
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    • 제13권2호
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    • pp.317-328
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    • 2002
  • We first derive group ordering reference priors in a two-way mixed-effects analysis of variance (ANOVA) model. We show that posterior distributions are proper and provide marginal posterior distributions under reference priors. We also examine whether the reference priors satisfy the probability matching criterion. Finally, the reference prior satisfying the probability matching criterion is shown to be good in the sense of frequentist coverage probability of the posterior quantile.

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조명차에 강인한 BP 기반의 스테레오 정합 시스템의 구현 (Implementation of Robust Stereo Matching Under Variable Illumination Conditions With Belief Propagation)

  • 나인태;정홍
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2008년도 하계종합학술대회
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    • pp.737-738
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    • 2008
  • An implementation of robust stereo matching algorithm under variable illumination conditions is presented in this paper. By applying window-based matchingmethod to global stereo matching algorthm using belief propagation, our implemented system shows low error rate and could efficiently cope with general radiometric disimilarities between images acquired from two different point of views.

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비선형시스템의 새로운 통계적 선형화방법 (A New Statistical Linearization Technique of Nonlinear System)

  • 이장규;이연석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1990년도 하계학술대회 논문집
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    • pp.72-76
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    • 1990
  • A new statistical linearization technique for nonlinear system called covariance matching method is proposed in this paper. The covariance matching method makes the mean and variance of an approximated output be identical real functional output, and the distribution of the approximated output have identical shape with a given random input. Also, the covariance matching method can be easily implemented for statistical analysis of nonlinear systems with a combination of linear system covariance analysis.

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정규화된 블록매칭과 POCS에 의한 HR 영상 재구성 (Reconstruction of HR by POCS and Regularized Block Matching)

  • 최종범;오태석;김용철
    • 한국통신학회논문지
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    • 제30권8C호
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    • pp.824-831
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    • 2005
  • LR 영상을 이용하는 HR 영상 재구성에서 추정된 움직임 벡터의 오류는 재구성된 영상의 화질을 저하시킨다. 이를 해결하기 위해 움직임 추정과 HR 영상의 추정을 동시에 하는 방법들이 제안되었으나, 블록 정합법과 같은 간단한 방법을 사용하는 경우 추정된 움직임 벡터에는 여전히 오류가 발생한다. 본 논문에서는 정규화된 움직임 추정과 POCS를 이용한 HR 영상 재구성을 동시에 하는 IBR 재구성 방법을 제안한다. 이 방법에서는 어느 한 화소의 움직임 벡터가 이웃의 움직임 벡터들과 연관성이 있음을 이용하여 블록 정합법에 정규화를 적용하여 움직임 추정이 이루어진다. 제안된 방법을 사용한 실험 결과 종래의 방법에 비하여 움직임 추정이 개선되었으며 이에 따라서 재구성된 고해상도 영상의 화질과 PSNR이 현저히 개선되었다.

Analysis of Database Referenced Navigation by the Combination of Heterogeneous Geophysical Data and Algorithms

  • Lee, Jisun;Kwon, Jay Hyoun
    • 한국측량학회지
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    • 제34권4호
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    • pp.373-382
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    • 2016
  • In this study, an EKF (Extended Kalman Filter) based database reference navigation using both gravity gradient and terrain data was performed to complement the weakness of using only one type of geophysical DB (Database). Furthermore, a new algorithm which combines the EKF and profile matching was developed to improve the stability and accuracy of the positioning. On the basis of simulations, it was found that the overall navigation performance was improved by the combination of geophysical DBs except the two trajectories in which the divergence of TRN (Terrain Referenced Navigation) occurred. To solve the divergence problem, the profile matching algorithm using the terrain data is combined with the EKF. The results show that all trajectories generate the stable performance with positioning error ranges between 14m to 23m although not all trajectories positioning accuracy is improved. The average positioning error from the combined algorithm for all nine trajectories is about 18 m. For further study, a development of a switching geophysical DB or algorithm between the EKF and the profile matching to improve the navigation performance is suggested.

영상을 이용한 주행차량 위치정보와 GIS 차선 데이터 매칭 기법 (Matching GIS Lane Data with Vehicle Position Using Camera Image)

  • 김민우;문상찬;주다니;이순걸
    • 한국자동차공학회논문집
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    • 제22권7호
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    • pp.40-47
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    • 2014
  • This paper proposes a matching method of GIS lane information with a vehicle position using camera image to reduce DGPS error. Images of straight road are taken using a camera that is installed on the front center of the vehicle, and the distance between the vehicle and the lane are estimated using the images. The current GIS lane data is matched by comparing the estimated distance and the measured distance using a DGPS. Inverse perspective mapping is used to minimize the error of image processing from the heading angle, and single buffering method is applied to decide the exact moment of GIS match. Through practical test on the highway, feasibility of the GIS matching using camera image is confirmed.