• 제목/요약/키워드: Matching Methods

검색결과 1,457건 처리시간 0.027초

Statistical micro matching using a multinomial logistic regression model for categorical data

  • Kim, Kangmin;Park, Mingue
    • Communications for Statistical Applications and Methods
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    • 제26권5호
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    • pp.507-517
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    • 2019
  • Statistical matching is a method of combining multiple sources of data that are extracted or surveyed from the same population. It can be used in situation when variables of interest are not jointly observed. It is a low-cost way to expect high-effects in terms of being able to create synthetic data using existing sources. In this paper, we propose the several statistical micro matching methods using a multinomial logistic regression model when all variables of interest are categorical or categorized ones, which is common in sample survey. Under conditional independence assumption (CIA), a mixed statistical matching method, which is useful when auxiliary information is not available, is proposed. We also propose a statistical matching method with auxiliary information that reduces the bias of the conventional matching methods suggested under CIA. Through a simulation study, proposed micro matching methods and conventional ones are compared. Simulation study shows that suggested matching methods outperform the existing ones especially when CIA does not hold.

특징점과 필터뱅크에 기반한 적응적 혼합형 지문정합 방법 (Adaptive Hybrid Fingerprint Matching Method Based on Minutiae and Filterbank)

  • 정석재;박상현;문성림;김동윤
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제31권7호
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    • pp.959-967
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    • 2004
  • Jain 등은 한 지문 영상에 특징점 기반 지문 정합 방법과 필터뱅크 기반 지문 정합 방법을 적용해 두 정합 방법의 성능을 혼합하는 혼합형 지문정합 방법을 제안하고, 이 방법이 두 가지 각 정합 방법에 비해 높은 성능을 보인다는 것을 실험을 통해 입증하였다[l]. 그러나 이 방법은 혼합을 수행할 때 두 정합 방법을 별도로 수행한 후, 각 방법의 정합도(matching score)에 가중치를 부여해 최종 정합도를 결정하므로 두 정합 방법의 특성을 상쇄 시키는 결과를 얻게 된다. 본 논문에서는 두 가지 정합 방법을 특징값 추출 과정에서 혼합하는 방법을 제안하였다. 이 방법은 필터뱅크 기반 방법보다는 낮은 ERR(Equal eRror Rate)을 보이나 특징점 기반 방법보다 높은 ERR을 보였다. 이에 본 논문에서는 적응적인 정합도 혼합방법을 제안하여, 두 가지 방법의 특성을 살리도록 적응적으로 정합도를 선택하는 방법을 취했다. 이 방법을 이용해 Jain 등의 혼합형 방법보다 더 낮은 ERR을 얻을 수 있었다. 제안한 방법에 따라 NIST Special Database 14 지문 데이타로 실험한 결과 ERR에서 약 1%의 성능 향상을 보였다.

한국 주식 데이터를 이용한 서브시퀀스 매칭 방법의 효과성 평가 (Effectiveness Evaluations of Subsequence Matching Methods Using KOSPI Data)

  • 유승근;이상호
    • 정보처리학회논문지D
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    • 제12D권3호
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    • pp.355-364
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    • 2005
  • 기존의 서브시퀀스 매칭 방법은 검색을 효율적으로 수행하기 위한 인덱스 구성 방법에 대하여 연구하였으며, 서브시퀀스 매칭 방법의 효과성 평가를 고려하지 않았다. 본 논문은 서브시퀀스 매칭 방법의 효과성에 대하여 고려하였으며, 서브시퀀스 매칭 방법의 효과성을 평가 할 수 있는 2가지 척도를 제안한다. 한국 주식 데이터와 5가지 서브시퀀스 매칭 방법에 대하여 제안된 효과성 측정 방안을 적용하였으며, 그 결과를 분석하였다. 실험 결과, 정규화를 지원하는 서브시퀀스 매칭 방법과 스케일링과 쉬프팅 변환을 지원하는 서브시퀀스 매칭 방법이 상대적으로 효과적인 서브시퀀스를 검색하였다.

DEM 제작을 위한 Adaptive Stereo Matching 에 관한 연구 (A Study on Adaptive Stereo Matching for DEM Generation)

  • 김정기;김정호;엄기문;이쾌희
    • 대한원격탐사학회지
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    • 제8권1호
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    • pp.15-26
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    • 1992
  • This paper describes an implementation of adaptive stereo matching for DBM generation. The matching method of two stereo satellite images to find corresponding points used in this paper is area-based matching, which is usually used in the field of making DBM. Same window size and search area used as in the conventional matching methods and we propose adaptive stereo matching algorithm in this paper. We cluster three areas which are consist of mountainous areas, cultivated areas and cities, and rivers and lakes by using proposed linear feature extracting method. These classified areas are matched by adaptive window size and search area, but rivers and lakes is excluded in this experiment. The matching time is three times faster than conventional methods.

온톨로지 트리기반 멀티에이전트 세만틱 유사도매칭 알고리즘 (A Multi-Agent Improved Semantic Similarity Matching Algorithm Based on Ontology Tree)

  • ;조영임
    • 제어로봇시스템학회논문지
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    • 제18권11호
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    • pp.1027-1033
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    • 2012
  • Semantic-based information retrieval techniques understand the meanings of the concepts that users specify in their queries, but the traditional semantic matching methods based on the ontology tree have three weaknesses which may lead to many false matches, causing the falling precision. In order to improve the matching precision and the recall of the information retrieval, this paper proposes a multi-agent improved semantic similarity matching algorithm based on the ontology tree, which can avoid the considerable computation redundancies and mismatching during the entire matching process. The results of the experiments performed on our algorithm show improvements in precision and recall compared with the information retrieval techniques based on the traditional semantic similarity matching methods.

고속 Block Matching 알고리즘에 관한 연구 (A Study on the Fast Block Matching Algorithm)

  • 이인홍;박래홍
    • 대한전자공학회논문지
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    • 제24권4호
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    • pp.667-674
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    • 1987
  • In this paper an effective block matching algorithm is proposed to find the motion vector. There are two approaches to the estimation of the motion vector in MCC (motion compensated coding), i.e., pel(pixel element) recursive algorithm and block matching algorithm. The search algorithm in this paper is based on the block matching method. The advantage of a proposed algorithm using integral projections is the reduction of the computation time. While the conventional block matching methods have to be computed in 2-dimensional arrays, the proposed algorithm using integral projections can be computed in 1-dimensional arrays. In comparison with conventional block matching methods, a computer simulation shows that though the prediction error increases 0.23 db, it is not detectable for human eyes and the average reduction ratio of computation time obtained from the proposed algorithm is about 3-4.

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에지 정보와 밝기 정보를 이용한 특징 기반 정합 (Feature based matching using edge and intensity)

  • 김정호;엄기문;이쾌희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1993년도 하계학술대회 논문집 A
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    • pp.414-417
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    • 1993
  • The methods for stereo matching are divided into two techniques: area-based matching and feature-based matching. To find corresponding points by area-based method, it takes a lot of time because there are many points to be matched. Feature-based matching algorithm is often used because with this method it matches only some feature points so that the processing time is fast even though it requires interpolation after matching. In this paper, we propose the smart technique by which we makes features simpler than conventional methods to match an image pair by feature-based matching algorithm.

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A FAST TEMPLATE MATCHING METHOD USING VECTOR SUMMATION OF SUBIMAGE PROJECTION

  • Kim, Whoi-Yul;Park, Yong-Sup
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 1999년도 KOBA 방송기술 워크샵 KOBA Broadcasting Technology Workshop
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    • pp.171-176
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    • 1999
  • Template matching is one of the most often used techniques for machine vision applications to find a template of size M$\times$M or subimage in a scene image of size N$\times$N. Most template matching methods, however, require pixel operations between the template and the image under analysis resulting in high computational cost of O(M2N2). So in this thesis, we present a two stage template matching method. In the first stage, we use a novel low cost feature whose complexity is approaching O(N2) to select matching candidates. In the second stage, we use conventional template matching method to find out the exact matching point. We compare the result with other methods in terms of complexity, efficiency and performance. Proposed method was proved to have constant time complexity and to be quite invariant to noise.

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.

Deep Local Multi-level Feature Aggregation Based High-speed Train Image Matching

  • Li, Jun;Li, Xiang;Wei, Yifei;Wang, Xiaojun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제16권5호
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    • pp.1597-1610
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    • 2022
  • At present, the main method of high-speed train chassis detection is using computer vision technology to extract keypoints from two related chassis images firstly, then matching these keypoints to find the pixel-level correspondence between these two images, finally, detection and other steps are performed. The quality and accuracy of image matching are very important for subsequent defect detection. Current traditional matching methods are difficult to meet the actual requirements for the generalization of complex scenes such as weather, illumination, and seasonal changes. Therefore, it is of great significance to study the high-speed train image matching method based on deep learning. This paper establishes a high-speed train chassis image matching dataset, including random perspective changes and optical distortion, to simulate the changes in the actual working environment of the high-speed rail system as much as possible. This work designs a convolutional neural network to intensively extract keypoints, so as to alleviate the problems of current methods. With multi-level features, on the one hand, the network restores low-level details, thereby improving the localization accuracy of keypoints, on the other hand, the network can generate robust keypoint descriptors. Detailed experiments show the huge improvement of the proposed network over traditional methods.