• 제목/요약/키워드: FEATURE

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A Computer-Aided Inspection Planning System for On-Machine Measurement - Part I : Global Inspection Planning -

  • Lee, Hong-Hee;Cho, Myeong-Woo;Yoon, Gil-Sang;Choi, Jin-Hwa
    • Journal of Mechanical Science and Technology
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    • 제18권8호
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    • pp.1349-1357
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    • 2004
  • Computer-Aided Inspection Planning (CAIP) is the integration bridge between CAD/CAM and Computer Aided Inspection (CAI). A CAIP system for On-Machine Measurement (OMM) is proposed to inspect the complicated mechanical parts efficiently during machining or after machining. The inspection planning consists of Global Inspection Planning (GIP) and Local Inspection Planning (LIP). In the GIP, the system creates the optimal inspection sequence of the features in a part by analyzing the various feature information such as the relationship of the features, Probe Approach Directions (PAD), etc. Feature groups are formed for effective planning, and special feature groups are determined for sequencing. The integrated process and inspection plan is generated based on the sequences of the feature groups and the features in a feature group. A series of heuristic rules are developed to accomplish it. In the LIP of Part II, the system generates inspection parameters. The integrated inspection planning is able to determine optimum manufacturing sequence for inspection and machining processes. Finally, the results are simulated and analyzed to verify the effectiveness of the proposed CAIP.

스테레오 영상의 정합값을 통한 얼굴특징 추출 방법 (Face Feature Extraction Method ThroughStereo Image's Matching Value)

  • 김상명;박장한;남궁재찬
    • 한국멀티미디어학회논문지
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    • 제8권4호
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    • pp.461-472
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    • 2005
  • 본 논문에서는 스테레오 영상의 정합값(matching)을 통한 얼굴 특징추출 알고리즘을 제안한다. 제안된 알고리즘에서는 얼굴색상 정보의 RGB컬러공간을 YCbCr컬러공간으로 변환하여 얼굴영역 검출하였다. 추출된 얼굴영역으로부터 눈 형판(template)을 적용하여 눈 사이의 거리와 기울어짐, 코와 입에 대한 특징의 기하학적인 특징 벡터를 추출하였다. 또한 제안한 방법은 2차원 특징정보 뿐만 아니라 스테레오 영상의 정합을 통한 얼굴의 눈, 코, 입의 특징을 추출할 수 있었다. 실험을 통하여 약 1m이내 거리에서 73%의 일치율을 보였고, 약 1m이후 거리에선 52%의 일치율을 보였다.

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지능형 휠체어 적용을 위해 Haar-like의 기울기 특징을 이용한 아다부스트 알고리즘 기반의 보행자 인식 (Pedestrian recognition using differential Haar-like feature based on Adaboost algorithm to apply intelligence wheelchair)

  • 이상훈;박상희;이영학;서희돈
    • 대한의용생체공학회:의공학회지
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    • 제31권6호
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    • pp.481-486
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    • 2010
  • In this paper, we suggest an advanced algorithm, to recognize pedestrian/non-pedestrian using differential haar-like feature, which applies Adaboost algorithm to make a strong classification from weak classifications. First, we extract two feature vectors: horizontal haar-like feature and vertical haar-like feature. For the next, we calculate the proposed feature vector using differential haar-like method. And then, a strong classification needs to be obtained from weak classifications for composite recognition method using the differential area of horizontal and vertical haar-like. In the proposed method, we use one feature vector and one strong classification for the first stage of recognition. Based on our experiment, the proposed algorithm shows higher recognition rate compared to the traditional method for the pedestrian and non-pedestrian.

Biological Feature Selection and Disease Gene Identification using New Stepwise Random Forests

  • Hwang, Wook-Yeon
    • Industrial Engineering and Management Systems
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    • 제16권1호
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    • pp.64-79
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    • 2017
  • Identifying disease genes from human genome is a critical task in biomedical research. Important biological features to distinguish the disease genes from the non-disease genes have been mainly selected based on traditional feature selection approaches. However, the traditional feature selection approaches unnecessarily consider many unimportant biological features. As a result, although some of the existing classification techniques have been applied to disease gene identification, the prediction performance was not satisfactory. A small set of the most important biological features can enhance the accuracy of disease gene identification, as well as provide potentially useful knowledge for biologists or clinicians, who can further investigate the selected biological features as well as the potential disease genes. In this paper, we propose a new stepwise random forests (SRF) approach for biological feature selection and disease gene identification. The SRF approach consists of two stages. In the first stage, only important biological features are iteratively selected in a forward selection manner based on one-dimensional random forest regression, where the updated residual vector is considered as the current response vector. We can then determine a small set of important biological features. In the second stage, random forests classification with regard to the selected biological features is applied to identify disease genes. Our extensive experiments show that the proposed SRF approach outperforms the existing feature selection and classification techniques in terms of biological feature selection and disease gene identification.

전정 유모세포 통합 모델을 이용한 반강성 기전 기반 섬모번들 특성 추정에 관한 연구 (A study on Hair Bundle Feature Estimation Based on Negative Stiffness Mechanism Using Integrated Vestibular Hair Cell Model)

  • 김동영;홍기환;김규성;이상민
    • 대한의용생체공학회:의공학회지
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    • 제34권4호
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    • pp.218-225
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    • 2013
  • In this paper hair bundle feature model and integration method for hair cell models were proposed. The proposed hair bundle feature model was based on spring-damper-mass model. Input of integrated vestibular hair cell model was frequency and output was interspike interval of hair cell that was reflected the feature of hair bundles. Irregular afferents that had a great gain variation showed reduction of negative stiffness section. Regular afferents that had a small gain variation, however, showed same feature with base negative stiffness feature. As a result, integrated vestibular hair cell model showed almost the same modeling data with experimental data in the modeled eleven frequency bands. It is verified that the proposed model is a good model for hair bundle feature modeling.

Emotion recognition from speech using Gammatone auditory filterbank

  • 레바부이;이영구;이승룡
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2011년도 한국컴퓨터종합학술대회논문집 Vol.38 No.1(A)
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    • pp.255-258
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    • 2011
  • An application of Gammatone auditory filterbank for emotion recognition from speech is described in this paper. Gammatone filterbank is a bank of Gammatone filters which are used as a preprocessing stage before applying feature extraction methods to get the most relevant features for emotion recognition from speech. In the feature extraction step, the energy value of output signal of each filter is computed and combined with other of all filters to produce a feature vector for the learning step. A feature vector is estimated in a short time period of input speech signal to take the advantage of dependence on time domain. Finally, in the learning step, Hidden Markov Model (HMM) is used to create a model for each emotion class and recognize a particular input emotional speech. In the experiment, feature extraction based on Gammatone filterbank (GTF) shows the better outcomes in comparison with features based on Mel-Frequency Cepstral Coefficient (MFCC) which is a well-known feature extraction for speech recognition as well as emotion recognition from speech.

Feature Selection via Embedded Learning Based on Tangent Space Alignment for Microarray Data

  • Ye, Xiucai;Sakurai, Tetsuya
    • Journal of Computing Science and Engineering
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    • 제11권4호
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    • pp.121-129
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    • 2017
  • Feature selection has been widely established as an efficient technique for microarray data analysis. Feature selection aims to search for the most important feature/gene subset of a given dataset according to its relevance to the current target. Unsupervised feature selection is considered to be challenging due to the lack of label information. In this paper, we propose a novel method for unsupervised feature selection, which incorporates embedded learning and $l_{2,1}-norm$ sparse regression into a framework to select genes in microarray data analysis. Local tangent space alignment is applied during embedded learning to preserve the local data structure. The $l_{2,1}-norm$ sparse regression acts as a constraint to aid in learning the gene weights correlatively, by which the proposed method optimizes for selecting the informative genes which better capture the interesting natural classes of samples. We provide an effective algorithm to solve the optimization problem in our method. Finally, to validate the efficacy of the proposed method, we evaluate the proposed method on real microarray gene expression datasets. The experimental results demonstrate that the proposed method obtains quite promising performance.

Projection Runlength를 이용한 필기체 숫자의 특징추출 (Feature Extraction of Handwritten Numerals using Projection Runlength)

  • 박중조;정순원;박영환;김경민
    • 제어로봇시스템학회논문지
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    • 제14권8호
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    • pp.818-823
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    • 2008
  • In this paper, we propose a feature extraction method which extracts directional features of handwritten numerals by using the projection runlength. Our directional featrures are obtained from four directional images, each of which contains horizontal, vertical, right-diagonal and left-diagonal lines in entire numeral shape respectively. A conventional method which extracts directional features by using Kirsch masks generates edge-shaped double line directional images for four directions, whereas our method uses the projections and their runlengths for four directions to produces single line directional images for four directions. To obtain the directional projections for four directions from a numeral image, some preprocessing steps such as thinning and dilation are required, but the shapes of resultant directional lines are more similar to the numeral lines of input numerals. Four [$4{\times}4$] directional features of a numeral are obtained from four directional line images through a zoning method. By using a hybrid feature which is made by combining our feature with the conventional features of a mesh features, a kirsch directional feature and a concavity feature, higher recognition rates of the handwrittern numerals can be obtained. For recognition test with given features, we use a multi-layer perceptron neural network classifier which is trained with the back propagation algorithm. Through the experiments with the handwritten numeral database of Concordia University, we have achieved a recognition rate of 97.85%.

Wavelet에 의한 의용영상의 병소부위 특징추출 (Disease Region Feature Extraction of Medical Image using Wavelet)

  • 이상복;이주신
    • 한국컴퓨터정보학회논문지
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    • 제3권3호
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    • pp.73-81
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    • 1998
  • 본 논문에서는 의용영상의 병소부위 특징을 추출하여 판별 자동화할 수 있는 방안을 제안하였다. 전처리 과정으로서 의용영상의 형태정보는 입력영상을 DWT(Discrete wavelet transform)에 의해 4레벨 DWT 계수 행렬을 구하고 계수 행렬의 특징에 따라 저주파 계수 행렬로부터 저주파 특징 파라미터 32개, 수평 고주파 계수 행렬로부터 수평 고주파특징 파라미터 16개, 수직 고주파 계수 행렬로부터 수직 고주파 특징 파라미터 16개, 그리고, 대각 고주파 계수 행렬로부터 대각 고주파 특징 파라미터 32개 등 모두 96개의 특징 파라미터를 추출하였다. 본 논문에서 제안된 알고리즘을 이용하면 자동 판별 시스템을 구축할수 있고, PACS의 성능 향상에 크게 기여할 것이다.

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조명 변이에 강인한 하이브리드 얼굴 인식 방법 (A Robust Hybrid Method for Face Recognition Under Illumination Variation)

  • 최상일
    • 전자공학회논문지
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    • 제52권10호
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    • pp.129-136
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    • 2015
  • 본 논문에서는 조명 변이에 강인하게 동작 할 수 있는 하이브리드 얼굴 인식 방법을 제안한다. 이를 위해, 서로 다른 특성을 가진 조명 불변 특징 추출 방법으로부터 판별력 있는 특징들을 추출한다. 개별 방법들의 장점들을 효과적으로 활용하기 위해, 판별 거리 척도를 이용하여 각 특징들의 분별력을 측정하여 분별력이 높은 특징들로만 복합 특징을 구성하여 얼굴 인식에 사용한다. Multi-PIE, Yale B, AR, yale database들에 대한 실험 결과, 제안한 방법은 모든 database에 대해 개별 조명 불변 특징 방법들보다 우수한 인식 성능을 보여 주었다.