• 제목/요약/키워드: Computer Principal

검색결과 460건 처리시간 0.023초

뇌파 분류에 유용한 주성분 특징 (On Useful Principal Component Features for EEG Classification)

  • Park, Sungcheol;Lee, Hyekyoung;Park, Seungjin
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (B)
    • /
    • pp.178-180
    • /
    • 2003
  • EEG-based brain computer interface(BCI) provides a new communication channel between human brain and computer. EEG data is a multivariate time series so that hidden Markov model (HMM) might be a good choice for classification. However EEG is very noisy data and contains artifacts, so useful features mr expected to improve the performance of HMM. In this paper we addresses the usefulness of principal component features with Hidden Markov model (HHM). We show that some selected principal component features can suppress small noises and artifacts, hence improves classification performance. Experimental study for the classification of EEG data during imagination of a left, right up or down hand movement confirms the validity of our proposed method.

  • PDF

주성분 분석을 이용한 기울어진 얼굴에서의 눈동자 검출 (Eye detection on Rotated face using Principal Component Analysis)

  • 최연석;문원호;차의영
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국해양정보통신학회 2011년도 춘계학술대회
    • /
    • pp.61-64
    • /
    • 2011
  • 컴퓨터 비전을 이용한 눈동자 추적 기술은 Human-Computer Interface(HCI)의 중요성이 높아짐에 따라 많이 연구되고 있다. 본 논문에서는 HCI 장치를 위한 눈동자 검출 방법을 제안한다. 제안하는 방법은 기울어진 얼굴에서도 눈동자를 검출하기 위해 Principal Component Analysis(PCA) 방법을 이용하여 얼굴의 기울어진 정도를 검출하고 기울어진 정도를 이용하여 눈동자 영역의 위치를 계산한다. 최종적으로 눈 위치의 검출을 위해 눈동자 영역의 밝기 정보를 사용한다. FERET DB의 얼굴영상을 사용하여 실험한 결과, 기울어진 얼굴에서도 눈동자를 효과적으로 검출 할 수 있음을 확인하였다.

  • PDF

Term Frequency-Inverse Document Frequency (TF-IDF) Technique Using Principal Component Analysis (PCA) with Naive Bayes Classification

  • J.Uma;K.Prabha
    • International Journal of Computer Science & Network Security
    • /
    • 제24권4호
    • /
    • pp.113-118
    • /
    • 2024
  • Pursuance Sentiment Analysis on Twitter is difficult then performance it's used for great review. The present be for the reason to the tweet is extremely small with mostly contain slang, emoticon, and hash tag with other tweet words. A feature extraction stands every technique concerning structure and aspect point beginning particular tweets. The subdivision in a aspect vector is an integer that has a commitment on ascribing a supposition class to a tweet. The cycle of feature extraction is to eradicate the exact quality to get better the accurateness of the classifications models. In this manuscript we proposed Term Frequency-Inverse Document Frequency (TF-IDF) method is to secure Principal Component Analysis (PCA) with Naïve Bayes Classifiers. As the classifications process, the work proposed can produce different aspects from wildly valued feature commencing a Twitter dataset.

A Automatic Document Summarization Method based on Principal Component Analysis

  • Kim, Min-Soo;Lee, Chang-Beom;Baek, Jang-Sun;Lee, Guee-Sang;Park, Hyuk-Ro
    • Communications for Statistical Applications and Methods
    • /
    • 제9권2호
    • /
    • pp.491-503
    • /
    • 2002
  • In this paper, we propose a automatic document summarization method based on Principal Component Analysis(PCA) which is one of the multivariate statistical methods. After extracting thematic words using PCA, we select the statements containing the respective extracted thematic words, and make the document summary with them. Experimental results using newspaper articles show that the proposed method is superior to the method using either word frequency or information retrieval thesaurus.

Fast Pedestrian Detection Using Histogram of Oriented Gradients and Principal Components Analysis

  • Nguyen, Trung Quy;Kim, Soo Hyung;Na, In Seop
    • International Journal of Contents
    • /
    • 제9권3호
    • /
    • pp.1-9
    • /
    • 2013
  • In this paper, we propose a fast and accurate system for detecting pedestrians from a static image. Histogram of Oriented Gradients (HOG) is a well-known feature for pedestrian detection systems but extracting HOG is expensive due to its high dimensional vector. It will cause long processing time and large memory consumption in case of making a pedestrian detection system on high resolution image or video. In order to deal with this problem, we use Principal Components Analysis (PCA) technique to reduce the dimensionality of HOG. The output of PCA will be input for a linear SVM classifier for learning and testing. The experiment results showed that our proposed method reduces processing time but still maintains the similar detection rate. We got twenty five times faster than original HOG feature.

Performance Analysis of Perturbation-based Privacy Preserving Techniques: An Experimental Perspective

  • Ritu Ratra;Preeti Gulia;Nasib Singh Gill
    • International Journal of Computer Science & Network Security
    • /
    • 제23권10호
    • /
    • pp.81-88
    • /
    • 2023
  • In the present scenario, enormous amounts of data are produced every second. These data also contain private information from sources including media platforms, the banking sector, finance, healthcare, and criminal histories. Data mining is a method for looking through and analyzing massive volumes of data to find usable information. Preserving personal data during data mining has become difficult, thus privacy-preserving data mining (PPDM) is used to do so. Data perturbation is one of the several tactics used by the PPDM data privacy protection mechanism. In Perturbation, datasets are perturbed in order to preserve personal information. Both data accuracy and data privacy are addressed by it. This paper will explore and compare several perturbation strategies that may be used to protect data privacy. For this experiment, two perturbation techniques based on random projection and principal component analysis were used. These techniques include Improved Random Projection Perturbation (IRPP) and Enhanced Principal Component Analysis based Technique (EPCAT). The Naive Bayes classification algorithm is used for data mining approaches. These methods are employed to assess the precision, run time, and accuracy of the experimental results. The best perturbation method in the Nave-Bayes classification is determined to be a random projection-based technique (IRPP) for both the cardiovascular and hypothyroid datasets.

An improved kernel principal component analysis based on sparse representation for face recognition

  • Huang, Wei;Wang, Xiaohui;Zhu, Yinghui;Zheng, Gengzhong
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제10권6호
    • /
    • pp.2709-2729
    • /
    • 2016
  • Representation based classification, kernel method and sparse representation have received much attention in the field of face recognition. In this paper, we proposed an improved kernel principal component analysis method based on sparse representation to improve the accuracy and robustness for face recognition. First, the distances between the test sample and all training samples in kernel space are estimated based on collaborative representation. Second, S training samples with the smallest distances are selected, and Kernel Principal Component Analysis (KPCA) is used to extract the features that are exploited for classification. The proposed method implements the sparse representation under ℓ2 regularization and performs feature extraction twice to improve the robustness. Also, we investigate the relationship between the accuracy and the sparseness coefficient, the relationship between the accuracy and the dimensionality respectively. The comparative experiments are conducted on the ORL, the GT and the UMIST face database. The experimental results show that the proposed method is more effective and robust than several state-of-the-art methods including Sparse Representation based Classification (SRC), Collaborative Representation based Classification (CRC), KCRC and Two Phase Test samples Sparse Representation (TPTSR).

실측 파형과 수치 파형에 의한 진동주응력 비교 (Comparison of the Vibration Principal Stress by Experimental and Numerical Waveform)

  • 홍웅기;송정언;박영민
    • 환경영향평가
    • /
    • 제21권5호
    • /
    • pp.609-615
    • /
    • 2012
  • In recent years, the development of computer technique was possible to the simulation analysis of the structure caused by ground vibration. Generally, finite element method(FEM) has been used in these structural analysis. In this study, it was calculated to the vibration energy as measuring vibration waveform, and estimated about principal stress due to medium characteristics of the ground as processing dynamic analysis by the vibration energy. The results are as follows : Firstly, the principal stress distribution in all mediums was different due to a medium condition, and the principal stress at concrete medium was represented to difference due to physical characteristics. Secondly, the principal stress by time increasing was represented to maximum amplitude within 0.03 second. And also, the principal stress after maximum amplitude was very large at concrete medium, which was considered to be formed compression or tension range at a medium boundary. Thirdly, the variation of principal stress at concrete medium was represented in the order of RC medium, NC=H medium, NC=S medium. It was considered that the vibration energy propagated fast when a medium have a big elasticity and density.

Robust Design for Multiple Quality Characteristics using Principal Component Analysis

  • Kwon, Yong-Man;Hong, Yeon-Woong
    • Journal of the Korean Data and Information Science Society
    • /
    • 제14권3호
    • /
    • pp.545-551
    • /
    • 2003
  • Robust design is to identify appropriate settings of control factors that make the system's performance robust to changes in the noise factors that represent the source of variation. In this paper we propose how to simultaneously optimize multiple quality characteristics using the principal component analysis of multivariate statistical analysis. An example is illustrated to compare it with already proposed method.

  • PDF

Motion Recognition using Principal Component Analysis

  • Kwon, Yong-Man;Kim, Jong-Min
    • Journal of the Korean Data and Information Science Society
    • /
    • 제15권4호
    • /
    • pp.817-823
    • /
    • 2004
  • This paper describes a three dimensional motion recognition algorithm and a system which adopts the algorithm for non-contact human-computer interaction. From sequence of stereos images, five feature regions are extracted with simple color segmentation algorithm and then those are used for three dimensional locus calculation precess. However, the result is not so stable, noisy, that we introduce principal component analysis method to get more robust motion recognition results. This method can overcome the weakness of conventional algorithms since it directly uses three dimensional information motion recognition.

  • PDF