• Title/Summary/Keyword: Feature Classification

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Orthonormal Polynomial based Optimal EEG Feature Extraction for Motor Imagery Brain-Computer Interface

  • Chum, Pharino;Park, Seung-Min;Ko, Kwang-Eun;Sim, Kwee-Bo
    • Journal of the Korean Institute of Intelligent Systems
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    • v.22 no.6
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    • pp.793-798
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    • 2012
  • In this paper, we explored the new method for extracting feature from the electroencephalography (EEG) signal based on linear regression technique with the orthonormal polynomial bases. At first, EEG signals from electrodes around motor cortex were selected and were filtered in both spatial and temporal filter using band pass filter for alpha and beta rhymic band which considered related to the synchronization and desynchonization of firing neurons population during motor imagery task. Signal from epoch length 1s were fitted into linear regression with Legendre polynomials bases and extract the linear regression weight as final features. We compared our feature to the state of art feature, power band feature in binary classification using support vector machine (SVM) with 5-fold cross validations for comparing the classification accuracy. The result showed that our proposed method improved the classification accuracy 5.44% in average of all subject over power band features in individual subject study and 84.5% of classification accuracy with forward feature selection improvement.

Optimizing Feature Extractioin for Multiclass problems Based on Classification Error (다중 클래스 데이터를 위한 분류오차 최소화기반 특징추출 기법)

  • Choi, Eui-Sun;Lee, Chul-Hee
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.37 no.2
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    • pp.39-49
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    • 2000
  • In this paper, we propose an optimizing feature extraction method for multiclass problems assuming normal distributions. Initially, We start with an arbitrary feature vector Assuming that the feature vector is used for classification, we compute the classification error Then we move the feature vector slightly in the direction so that classification error decreases most rapidly This can be done by taking gradient We propose two search methods, sequential search and global search In the sequential search, an additional feature vector is selected so that it provides the best accuracy along with the already chosen feature vectors In the global search, we are not constrained to use the chosen feature vectors Experimental results show that the proposed algorithm provides a favorable performance.

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Classification of the PVC Using The Fuzzy-ART Network Based on Wavelet Coefficient (웨이브렛 계수에 근거한 Fuzzy-ART 네트워크를 이용한 PVC 분류)

  • Park, K. L;Lee, K. J.;lee, Y. S.;Yoon, H. R.
    • Journal of Biomedical Engineering Research
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    • v.20 no.4
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    • pp.435-442
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    • 1999
  • A fuzzy-ART(adaptive resonance theory) network for the PVC(premature ventricular contraction) classification using wavelet coefficient is designed. This network consists of the feature extraction and learning of the fuzzy-ART network. In the first step, we have detected the QRS from the ECG signal in order to set the threshold range for feature extraction and the detected QRS was divided into several frequency bands by wavelet transformation using Haar wavelet. Among the low-frequency bands, only the 6th coefficient(D6) are selected as the input feature. After that, the fuzzy-ART network for classification of the PVC is learned by using input feature which comprises of binary data converted by applying threshold to D6. The MIT/BIH database including the PVC is used for the evaluation. The designed fuzzy-ART network showed the PVC classification ratio of 96.52%.

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Application of Multi-Class AdaBoost Algorithm to Terrain Classification of Satellite Images

  • Nguyen, Ngoc-Hoa;Woo, Dong-Min
    • Journal of IKEEE
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    • v.18 no.4
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    • pp.536-543
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    • 2014
  • Terrain classification is still a challenging issue in image processing, especially with high resolution satellite images. The well-known obstacles include low accuracy in the detection of targets, especially for the case of man-made structures, such as buildings and roads. In this paper, we present an efficient approach to classify and detect building footprints, foliage, grass and road from high resolution grayscale satellite images. Our contribution is to build a strong classifier using AdaBoost based on a combination of co-occurrence and Haar-like features. We expect that the inclusion of Harr-like feature improves the classification performance of the man-made structures, since Haar-like feature is extracted from corner features and rectangle features. Also, the AdaBoost algorithm selects only critical features and generates an extremely efficient classifier. Experimental result indicates that the classification accuracy of AdaBoost classifier is much higher than that of the conventional classifier using back propagation algorithm. Also, the inclusion of Harr-like feature significantly improves the classification accuracy. The accuracy of the proposed method is 98.4% for the target detection and 92.8% for the classification on high resolution satellite images.

Feature-Vector Normalization for SVM-based Music Genre Classification (SVM에 기반한 음악 장르 분류를 위한 특징벡터 정규화 방법)

  • Lim, Shin-Cheol;Jang, Sei-Jin;Lee, Seok-Pil;Kim, Moo-Young
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.48 no.5
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    • pp.31-36
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    • 2011
  • In this paper, Mel-Frequency Cepstral Coefficient (MFCC), Decorrelated Filter Bank (DFB), Octave-based Spectral Contrast (OSC), Zero-Crossing Rate (ZCR), and Spectral Contract/Roll-Off are combined as a set of multiple feature-vectors for the music genre classification system based on the Support Vector Machine (SVM) classifier. In the conventional system, feature vectors for the entire genre classes are normalized for the SVM model training and classification. However, in this paper, selected feature vectors that are compared based on the One-Against-One (OAO) SVM classifier are only used for normalization. Using OSC as a single feature-vector and the multiple feature-vectors, we obtain the genre classification rates of 60.8% and 77.4%, respectively, with the conventional normalization method. Using the proposed normalization method, we obtain the increased classification rates by 8.2% and 3.3% for OSC and the multiple feature-vectors, respectively.

Effective Korean sentiment classification method using word2vec and ensemble classifier (Word2vec과 앙상블 분류기를 사용한 효율적 한국어 감성 분류 방안)

  • Park, Sung Soo;Lee, Kun Chang
    • Journal of Digital Contents Society
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    • v.19 no.1
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    • pp.133-140
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    • 2018
  • Accurate sentiment classification is an important research topic in sentiment analysis. This study suggests an efficient classification method of Korean sentiment using word2vec and ensemble methods which have been recently studied variously. For the 200,000 Korean movie review texts, we generate a POS-based BOW feature and a feature using word2vec, and integrated features of two feature representation. We used a single classifier of Logistic Regression, Decision Tree, Naive Bayes, and Support Vector Machine and an ensemble classifier of Adaptive Boost, Bagging, Gradient Boosting, and Random Forest for sentiment classification. As a result of this study, the integrated feature representation composed of BOW feature including adjective and adverb and word2vec feature showed the highest sentiment classification accuracy. Empirical results show that SVM, a single classifier, has the highest performance but ensemble classifiers show similar or slightly lower performance than the single classifier.

Text Classification based on a Feature Projection Technique with Robustness from Noisy Data (오류 데이타에 강한 자질 투영법 기반의 문서 범주화 기법)

  • 고영중;서정연
    • Journal of KIISE:Software and Applications
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    • v.31 no.4
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    • pp.498-504
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    • 2004
  • This paper presents a new text classifier based on a feature projection technique. In feature projections, training documents are represented as the projections on each feature. A classification process is based on individual feature projections. The final classification is determined by the sum from the individual classification of each feature. In our experiments, the proposed classifier showed high performance. Especially, it have fast execution speed and robustness with noisy data in comparison with k-NN and SVM, which are among the state-of-art text classifiers. Since the algorithm of the proposed classifier is very simple, its implementation and training process can be done very simply. Therefore, it can be a useful classifier in text classification tasks which need fast execution speed, robustness, and high performance.

Intelligent Feature Extraction and Scoring Algorithm for Classification of Passive Sonar Target (수동 소나 표적의 식별을 위한 지능형 특징정보 추출 및 스코어링 알고리즘)

  • Kim, Hyun-Sik
    • Journal of the Korean Institute of Intelligent Systems
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    • v.19 no.5
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    • pp.629-634
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    • 2009
  • In real-time system application, the feature extraction and scoring algorithm for classification of the passive sonar target has the following problems: it requires an accurate and efficient feature extraction method because it is very difficult to distinguish the features of the propeller shaft rate (PSR) and the blade rate (BR) from the frequency spectrum in real-time, it requires a robust and effective feature scoring method because the classification database (DB) composed of extracted features is noised and incomplete, and further, it requires an easy design procedure in terms of structures and parameters. To solve these problems, an intelligent feature extraction and scoring algorithm using the evolution strategy (ES) and the fuzzy theory is proposed here. To verify the performance of the proposed algorithm, a passive sonar target classification is performed in real-time. Simulation results show that the proposed algorithm effectively solves sonar classification problems in real-time.

Diagnosis of Alzheimer's Disease using Wrapper Feature Selection Method

  • Vyshnavi Ramineni;Goo-Rak Kwon
    • Smart Media Journal
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    • v.12 no.3
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    • pp.30-37
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    • 2023
  • Alzheimer's disease (AD) symptoms are being treated by early diagnosis, where we can only slow the symptoms and research is still undergoing. In consideration, using T1-weighted images several classification models are proposed in Machine learning to identify AD. In this paper, we consider the improvised feature selection, to reduce the complexity by using wrapping techniques and Restricted Boltzmann Machine (RBM). This present work used the subcortical and cortical features of 278 subjects from the ADNI dataset to identify AD and sMRI. Multi-class classification is used for the experiment i.e., AD, EMCI, LMCI, HC. The proposed feature selection consists of Forward feature selection, Backward feature selection, and Combined PCA & RBM. Forward and backward feature selection methods use an iterative method starting being no features in the forward feature selection and backward feature selection with all features included in the technique. PCA is used to reduce the dimensions and RBM is used to select the best feature without interpreting the features. We have compared the three models with PCA to analysis. The following experiment shows that combined PCA &RBM, and backward feature selection give the best accuracy with respective classification model RF i.e., 88.65, 88.56% respectively.

A Study on Vehicle Target Classification Method Using Both Shape and Local Features with Segmentation Reliability (표적분할 신뢰도 값 기반의 형태특징과 지역특징을 이용한 차량표적 분류기법 연구)

  • Yang, DongWon;Lee, Yonghun;Kwak, Dongmin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.20 no.1
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    • pp.40-47
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    • 2017
  • To classify the vehicle targets automatically using thermal images, there are usually two main categories of feature extraction method, local and shape feature extraction methods. Since thermal images have less texture information than color images, the shape feature extraction method is useful when the segmentation results are correct. However, if there are some errors in target segmentation, the shape feature may contain some errors, then the classification accuracy can be decreased. To overcome these problems, in this paper, we propose the segmentation reliability estimation method for target classification. The segmentation reliability can be estimated by using the difference information of average intensities and edge energies between the target and the background area. The estimated segmentation reliability is applied in the decision level fusion method of classification results using both shape and local features. Experiment results using the thermal images of the vehicle targets (main battle tank, armored personnel carrier, military truck, and an estate car) show that the proposed classification method and the segmentation reliability estimation method have a good performance in classification accuracy.