• 제목/요약/키워드: feature extract

검색결과 1,153건 처리시간 0.028초

AE 신호 및 신경회로망을 이용한 공작기계 주축용 베어링 결함검출 (Detection of Main Spindle Bearing Defects in Machine Tool by Acoustic Emission Signal via Neural Network Methodology)

  • 정의식
    • 한국생산제조학회지
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    • 제6권4호
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    • pp.46-53
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    • 1997
  • This paper presents a method of detection localized defects on tapered roller bearing in main spindle of machine tool system. The feature vectors, i.e. statistical parameters, in time-domain analysis technique have been calculated to extract useful features from acoustic emission signals. These feature vectors are used as the input feature of an neural network to classify and detect bearing defects. As a results, the detection of bearing defect conditions could be sucessfully performed by using an neural network with statistical parameters of acoustic emission signals.

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아바타 생성을 위한 이목구비 모양 특징정보 추출 및 분류에 관한 연구 (A Study on Facial Feature' Morphological Information Extraction and Classification for Avatar Generation)

  • 박연출
    • 한국컴퓨터산업학회논문지
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    • 제4권10호
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    • pp.631-642
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    • 2003
  • 본 논문에서는 웹상에서 자신을 대신하는 아바타 제작시 본인의 얼굴과 닮은 얼굴을 생성하기 위해 사진으로부터 개인의 특징정보를 추출하는 방법과 추출된 특징정보에 따라 해당하는 이목구비를 준비된 분류기준에 의해 특정 클래스로 분류해 내는 방법을 제안한다. 특징정보 추출은 눈, 코, 입, 턱선으로 나누어 진행되어졌으며, 각 이목구비의 특징점과 분류기준을 각각 제시하였다. 추출 된 특징정보들은 전문 디자이너에 의해 그려진 이목구비 이미지들과 유사도를 계산하는데 사용되었으며, 여기서 가장 유사한 이미지를 턱선 벡터이미지에 합성하여 아바타 얼굴을 얻어낼 수 있었다.

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특징형상기반 다중해상도 모델링의 상세수준 결정기준에 관한 연구 (A Study on the Criteria of the Level-Of-Detail in Feature-based Multi-resolution Modeling)

  • 이상헌;이규열
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.828-831
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    • 2005
  • In feature-based multi-resolution modeling, the features are rearranged according to a criterion for the levels of detail (LOD) of multi-resolution models. In this paper, two different LOD criteria are investigated and discussed. The one is the volumes of subtractive features, together with the precedence of additive features over subtractive features. The other is the volumes of features, regardless of whether the feature types are subtractive or additive. In addition, the algorithms to define and extract the LOD models based on the criteria are also described. The criterion of the volumes of features can be used for a wide range of applications in CAD and CAE in virtue of its generality.

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유비쿼터스 로봇과 휴먼 인터액션을 위한 제스쳐 추출 (Gesture Extraction for Ubiquitous Robot-Human Interaction)

  • 김문환;주영훈;박진배
    • 제어로봇시스템학회논문지
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    • 제11권12호
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    • pp.1062-1067
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    • 2005
  • This paper discusses a skeleton feature extraction method for ubiquitous robot system. The skeleton features are used to analyze human motion and pose estimation. In different conventional feature extraction environment, the ubiquitous robot system requires more robust feature extraction method because it has internal vibration and low image quality. The new hybrid silhouette extraction method and adaptive skeleton model are proposed to overcome this constrained environment. The skin color is used to extract more sophisticated feature points. Finally, the experimental results show the superiority of the proposed method.

Comparing Feature Selection Methods in Spam Mail Filtering

  • Kim, Jong-Wan;Kang, Sin-Jae
    • 한국정보기술응용학회:학술대회논문집
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    • 한국정보기술응용학회 2005년도 6th 2005 International Conference on Computers, Communications and System
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    • pp.17-20
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    • 2005
  • In this work, we compared several feature selection methods in the field of spam mail filtering. The proposed fuzzy inference method outperforms information gain and chi squared test methods as a feature selection method in terms of error rate. In the case of junk mails, since the mail body has little text information, it provides insufficient hints to distinguish spam mails from legitimate ones. To address this problem, we follow hyperlinks contained in the email body, fetch contents of a remote web page, and extract hints from both original email body and fetched web pages. A two-phase approach is applied to filter spam mails in which definite hint is used first, and then less definite textual information is used. In our experiment, the proposed two-phase method achieved an improvement of recall by 32.4% on the average over the $1^{st}$ phase or the $2^{nd}$ phase only works.

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컴퓨터 시각과 레이저 구조광을 이용한 물체의 3차원 정보 추출 (Three Dimensional Geometric Feature Detection Using Computer Vision System and Laser Structured Light)

  • 황헌;장영창;임동혁
    • Journal of Biosystems Engineering
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    • 제23권4호
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    • pp.381-390
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    • 1998
  • An algorithm to extract the 3-D geometric information of a static object was developed using a set of 2-D computer vision system and a laser structured lighting device. As a structured light pattern, multi-parallel lines were used in the study. The proposed algorithm was composed of three stages. The camera calibration, which determined a coordinate transformation between the image plane and the real 3-D world, was performed using known 6 pairs of points at the first stage. Then, utilizing the shifting phenomena of the projected laser beam on an object, the height of the object was computed at the second stage. Finally, using the height information of the 2-D image point, the corresponding 3-D information was computed using results of the camera calibration. For arbitrary geometric objects, the maximum error of the extracted 3-D feature using the proposed algorithm was less than 1~2mm. The results showed that the proposed algorithm was accurate for 3-D geometric feature detection of an object.

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Global Feature Extraction and Recognition from Matrices of Gabor Feature Faces

  • Odoyo, Wilfred O.;Cho, Beom-Joon
    • Journal of information and communication convergence engineering
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    • 제9권2호
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    • pp.207-211
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    • 2011
  • This paper presents a method for facial feature representation and recognition from the Covariance Matrices of the Gabor-filtered images. Gabor filters are a very powerful tool for processing images that respond to different local orientations and wave numbers around points of interest, especially on the local features on the face. This is a very unique attribute needed to extract special features around the facial components like eyebrows, eyes, mouth and nose. The Covariance matrices computed on Gabor filtered faces are adopted as the feature representation for face recognition. Geodesic distance measure is used as a matching measure and is preferred for its global consistency over other methods. Geodesic measure takes into consideration the position of the data points in addition to the geometric structure of given face images. The proposed method is invariant and robust under rotation, pose, or boundary distortion. Tests run on random images and also on publicly available JAFFE and FRAV3D face recognition databases provide impressively high percentage of recognition.

Implementation of Fingerprint Recognition System Based on the Embedded LINUX

  • Bae, Eun-Dae;Kim, Jeong-Ha;Nam, Boo-Hee
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.1550-1552
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    • 2005
  • In this paper, we have designed a Fingerprint Recognition System based on the Embedded LINUX. The fingerprint is captured using the AS-S2 semiconductor sensor. To extract a feature vector we transform the image of the fingerprint into a column vector. The image is row-wise filtered with the low-pass filter of the Haar wavelet. The feature vectors of the different fingerprints are compared by computing with the probabilistic neural network the distance between the target feature vector and the stored feature vectors in advance. The system implemented consists of a server PC based on the LINUX and a client based on the Embedded LINUX. The client is a Tynux box-x board using a PXA-255 CPU. The algorithm is simple and fast in computing and comparing the fingerprints.

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임베디드 리눅스 기반의 지문 인식 시스템 구현 (Implementation of Fingerprint Cognition System Based on the Embedded LINUX)

  • 배은대;김정하;남부희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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    • pp.204-206
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    • 2005
  • In this paper, we have designed a Fingerprint Recognition System based on the Embedded LINUX. The fingerprint is captured using the AS-S2 semiconductor sensor. To extract a feature vector we transform the image of t10he fingerprint into a column vector. The image is row-wise filtered with the low-pass filter of the Haar wavelet. The feature vectors of the different fingerprints are compared by computing with the probabilistic neural network the distance between the target feature vector and the stored feature vectors in advance. The system implemented consists of a server PC based on the LINUX and a client based on the Embedded LINUX. The client is a Tynux box-x board using a PXA-255 CPU. The algorithm is simple and fast in computing and comparing the fingerprints.

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Stacked Autoencoder를 이용한 특징 추출 기반 Fuzzy k-Nearest Neighbors 패턴 분류기 설계 (Design of Fuzzy k-Nearest Neighbors Classifiers based on Feature Extraction by using Stacked Autoencoder)

  • 노석범;오성권
    • 전기학회논문지
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    • 제64권1호
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    • pp.113-120
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    • 2015
  • In this paper, we propose a feature extraction method using the stacked autoencoders which consist of restricted Boltzmann machines. The stacked autoencoders is a sort of deep networks. Restricted Boltzmann machines (RBMs) are probabilistic graphical models that can be interpreted as stochastic neural networks. In terms of pattern classification problem, the feature extraction is a key issue. We use the stacked autoencoders networks to extract new features which have a good influence on the improvement of the classification performance. After feature extraction, fuzzy k-nearest neighbors algorithm is used for a classifier which classifies the new extracted data set. To evaluate the classification ability of the proposed pattern classifier, we make some experiments with several machine learning data sets.