• 제목/요약/키워드: Feature-based Method

검색결과 3,715건 처리시간 0.039초

복잡한 영상으로 부터의 선형 특징 추출 (Linear Feature Detection from Complex Scene Imagery)

  • 송오영;석민수
    • 대한전자공학회논문지
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    • 제20권1호
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    • pp.7-14
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    • 1983
  • 직선 및 곡선과 같은 선형 특징은 영상 처리에 있어 중요한 특징중의 하나이다. 본 논문에서는 의미있는 선형 특징의 새로운 기법이 제안된다. 이 기법은 그래프 이론의 미니멀 스패닝 트리를 이용하여 경계점들을 연결하고 그 다음, 헤어(의미없는 잔가지)와 불합리한 선분을 제거한다. 이와 같이 추적된 선형 특징을 근사화 묘사하기 위하여 부분 선형 근사화를 수행한다. 본 논문에서 제안된 기법으로 실험을 수행하여 그 결과를 보여 주었다.

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한국 남성의 고혈압에 대한 특징 선택 기반 위험 예측 (Feature selection-based Risk Prediction for Hypertension in Korean men)

  • 홍고르출;김미혜
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2021년도 춘계학술발표대회
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    • pp.323-325
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    • 2021
  • In this article, we have improved the prediction of hypertension detection using the feature selection method for the Korean national health data named by the KNHANES database. The study identified a variety of risk factors associated with chronic hypertension. The paper is divided into two modules. The first of these is a data pre-processing step that uses a factor analysis (FA) based feature selection method from the dataset. The next module applies a predictive analysis step to detect and predict hypertension risk prediction. In this study, we compare the mean standard error (MSE), F1-score, and area under the ROC curve (AUC) for each classification model. The test results show that the proposed FIFA-OE-NB algorithm has an MSE, F1-score, and AUC outcomes 0.259, 0.460, and 64.70%, respectively. These results demonstrate that the proposed FIFA-OE method outperforms other models for hypertension risk predictions.

LSG:모델 기반 3차원 물체 인식을 위한 정형화된 국부적인 특징 구조 (LSG;(Local Surface Group); A Generalized Local Feature Structure for Model-Based 3D Object Recognition)

  • 이준호
    • 정보처리학회논문지B
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    • 제8B권5호
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    • pp.573-578
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    • 2001
  • This research proposes a generalized local feature structure named "LSG(Local Surface Group) for model-based 3D object recognition". An LSG consists of a surface and its immediately adjacent surface that are simultaneously visible for a given viewpoint. That is, LSG is not a simple feature but a viewpoint-dependent feature structure that contains several attributes such as surface type. color, area, radius, and simultaneously adjacent surface. In addition, we have developed a new method based on Bayesian theory that computes a measure of how distinct an LSG is compared to other LSGs for the purpose of object recognition. We have experimented the proposed methods on an object databaed composed of twenty 3d object. The experimental results show that LSG and the Bayesian computing method can be successfully employed to achieve rapid 3D object recognition.

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LCD 패널 상의 불량 검출을 위한 스펙트럴 그래프 이론에 기반한 특성 추출 방법 (Feature extraction method using graph Laplacian for LCD panel defect classification)

  • 김규동;유석인
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2012년도 한국컴퓨터종합학술대회논문집 Vol.39 No.1(B)
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    • pp.522-524
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    • 2012
  • For exact classification of the defect, good feature selection and classifier is necessary. In this paper, various features such as brightness features, shape features and statistical features are stated and Bayes classifier using Gaussian mixture model is used as classifier. Also feature extraction method based on spectral graph theory is presented. Experimental result shows that feature extraction method using graph Laplacian result in better performance than the result using PCA.

Microblog User Geolocation by Extracting Local Words Based on Word Clustering and Wrapper Feature Selection

  • Tian, Hechan;Liu, Fenlin;Luo, Xiangyang;Zhang, Fan;Qiao, Yaqiong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권10호
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    • pp.3972-3988
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    • 2020
  • Existing methods always rely on statistical features to extract local words for microblog user geolocation. There are many non-local words in extracted words, which makes geolocation accuracy lower. Considering the statistical and semantic features of local words, this paper proposes a microblog user geolocation method by extracting local words based on word clustering and wrapper feature selection. First, ordinary words without positional indications are initially filtered based on statistical features. Second, a word clustering algorithm based on word vectors is proposed. The remaining semantically similar words are clustered together based on the distance of word vectors with semantic meanings. Next, a wrapper feature selection algorithm based on sequential backward subset search is proposed. The cluster subset with the best geolocation effect is selected. Words in selected cluster subset are extracted as local words. Finally, the Naive Bayes classifier is trained based on local words to geolocate the microblog user. The proposed method is validated based on two different types of microblog data - Twitter and Weibo. The results show that the proposed method outperforms existing two typical methods based on statistical features in terms of accuracy, precision, recall, and F1-score.

Hand-crafted 특징 및 머신 러닝 기반의 은하 이미지 분류 기법 개발 (Development of Galaxy Image Classification Based on Hand-crafted Features and Machine Learning)

  • 오윤주;정희철
    • 대한임베디드공학회논문지
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    • 제16권1호
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    • pp.17-27
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    • 2021
  • In this paper, we develop a galaxy image classification method based on hand-crafted features and machine learning techniques. Additionally, we provide an empirical analysis to reveal which combination of the techniques is effective for galaxy image classification. To achieve this, we developed a framework which consists of four modules such as preprocessing, feature extraction, feature post-processing, and classification. Finally, we found that the best technique for galaxy image classification is a method to use a median filter, ORB vector features and a voting classifier based on RBF SVM, random forest and logistic regression. The final method is efficient so we believe that it is applicable to embedded environments.

다중 채널 동적 객체 정보 추정을 통한 특징점 기반 Visual SLAM (A New Feature-Based Visual SLAM Using Multi-Channel Dynamic Object Estimation)

  • 박근형;조형기
    • 대한임베디드공학회논문지
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    • 제19권1호
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    • pp.65-71
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    • 2024
  • An indirect visual SLAM takes raw image data and exploits geometric information such as key-points and line edges. Due to various environmental changes, SLAM performance may decrease. The main problem is caused by dynamic objects especially in highly crowded environments. In this paper, we propose a robust feature-based visual SLAM, building on ORB-SLAM, via multi-channel dynamic objects estimation. An optical flow and deep learning-based object detection algorithm each estimate different types of dynamic object information. Proposed method incorporates two dynamic object information and creates multi-channel dynamic masks. In this method, information on actually moving dynamic objects and potential dynamic objects can be obtained. Finally, dynamic objects included in the masks are removed in feature extraction part. As a results, proposed method can obtain more precise camera poses. The superiority of our ORB-SLAM was verified to compared with conventional ORB-SLAM by the experiment using KITTI odometry dataset.

A Self-selection of Adaptive Feature using DCT

  • Lim, Seung-in
    • 한국컴퓨터정보학회논문지
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    • 제5권3호
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    • pp.215-219
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    • 2000
  • The purpose of this paper is to propose a method to maximize the efficiency of a content-based image retrieval for various kinds of images. This paper discuss the self-adaptivity for the change of image domain and the self-selection of optimal features for query image, and present the efficient method to maximize content-based retrieval for various kinds of images. In this method, a content-based retrieval system is adopted to select automatically distinctive feature patterns which have a maximum efficiency of image retrieval in various kinds of images. Experimental results show that the Proposed method is improved 3% than the method using individual features.

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영상 객체의 특징 추출을 이용한 내용 기반 영상 검색 시스템 (Content-Based Image Retrieval System using Feature Extraction of Image Objects)

  • 정세환;서광규
    • 산업경영시스템학회지
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    • 제27권3호
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    • pp.59-65
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    • 2004
  • This paper explores an image segmentation and representation method using Vector Quantization(VQ) on color and texture for content-based image retrieval system. The basic idea is a transformation from the raw pixel data to a small set of image regions which are coherent in color and texture space. These schemes are used for object-based image retrieval. Features for image retrieval are three color features from HSV color model and five texture features from Gray-level co-occurrence matrices. Once the feature extraction scheme is performed in the image, 8-dimensional feature vectors represent each pixel in the image. VQ algorithm is used to cluster each pixel data into groups. A representative feature table based on the dominant groups is obtained and used to retrieve similar images according to object within the image. The proposed method can retrieve similar images even in the case that the objects are translated, scaled, and rotated.

서브밴드 가중치를 이용한 잡음에 강인한 화자검증 (Noise Rabust Speaker Verification Using Sub-Band Weighting)

  • 김성탁;지미경;김회린
    • 한국음향학회지
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    • 제28권3호
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    • pp.279-284
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    • 2009
  • 화자검증은 발성화자가 제시화자 (claimed speaker)인지 아닌지를 구별하는 것이다. 기존의 화자검증 시스템인 GMM-UBM 방식의 화자검증 시스템은 무잡음 환경에서는 높은 검증성능을 보이지만, 잡음환경에서는 성능이 급격히 떨어지는 단점이 있다. 이런 단점을 극복하기 위해 멀티밴드를 이용한 방법인 특징벡터 재결합방법이 제안되었지만, 특징벡터 재결합방법은 전체 서브밴드 특징벡터들을 사용하여 유사도를 계산하는 단점이 있다. 이런 단점을 극복하기 위해 기 발표된 이전 논문에서 각 서브밴드 유사도를 독립적으로 계산하는 변형된 특징벡터 재결합방법을 제안하였고, 본 논문에서는 변형된 특징벡터 재결합방법과 각 서브밴드들의 신뢰도를 나타내는 신호 대 잡음비를 이용한 가중치를 이용하여 잡음환경에서 기존의 특징벡터 재결합방법에 비해 에러를 28% 감소시켰다.