• Title/Summary/Keyword: Correlation detection method

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Detection of Distinctive Points in Impedance Cardiogram during Exercise by Cross-Correlation Method (상호상관 관계를 이용한 운동중의 임피던스 파형에서의 특성점 검출)

  • 오인식;송철규
    • Journal of Biomedical Engineering Research
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    • v.12 no.4
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    • pp.261-266
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    • 1991
  • As the ensemble averaged dz/dt signal during exercise gets smoothed, it is difficult to find the distinctive marks for estimation of stroke volume. The cross correlation function was made use of estimating these marks for automatic calculation by computer from the ensemble averaged dz/dt signal. LVET( Left Ventricular Ejection Time) and stroke volume were estimated based on the calculated parameters from the characteristic points. LVET, stroke volume calculated by hand, by the ensemble average and the cross correlation were compared for accuracy validation.

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FAFS: A Fuzzy Association Feature Selection Method for Network Malicious Traffic Detection

  • Feng, Yongxin;Kang, Yingyun;Zhang, Hao;Zhang, Wenbo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.1
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    • pp.240-259
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    • 2020
  • Analyzing network traffic is the basis of dealing with network security issues. Most of the network security systems depend on the feature selection of network traffic data and the detection ability of malicious traffic in network can be improved by the correct method of feature selection. An FAFS method, which is short for Fuzzy Association Feature Selection method, is proposed in this paper for network malicious traffic detection. Association rules, which can reflect the relationship among different characteristic attributes of network traffic data, are mined by association analysis. The membership value of association rules are obtained by the calculation of fuzzy reasoning. The data features with the highest correlation intensity in network data sets are calculated by comparing the membership values in association rules. The dimension of data features are reduced and the detection ability of malicious traffic detection algorithm in network is improved by FAFS method. To verify the effect of malicious traffic feature selection by FAFS method, FAFS method is used to select data features of different dataset in this paper. Then, K-Nearest Neighbor algorithm, C4.5 Decision Tree algorithm and Naïve Bayes algorithm are used to test on the dataset above. Moreover, FAFS method is also compared with classical feature selection methods. The analysis of experimental results show that the precision and recall rate of malicious traffic detection in the network can be significantly improved by FAFS method, which provides a valuable reference for the establishment of network security system.

A Study on Text Pattern Analysis Applying Discrete Fourier Transform - Focusing on Sentence Plagiarism Detection - (이산 푸리에 변환을 적용한 텍스트 패턴 분석에 관한 연구 - 표절 문장 탐색 중심으로 -)

  • Lee, Jung-Song;Park, Soon-Cheol
    • Journal of Korea Society of Industrial Information Systems
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    • v.22 no.2
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    • pp.43-52
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    • 2017
  • Pattern Analysis is One of the Most Important Techniques in the Signal and Image Processing and Text Mining Fields. Discrete Fourier Transform (DFT) is Generally Used to Analyzing the Pattern of Signals and Images. We thought DFT could also be used on the Analysis of Text Patterns. In this Paper, DFT is Firstly Adapted in the World to the Sentence Plagiarism Detection Which Detects if Text Patterns of a Document Exist in Other Documents. We Signalize the Texts Converting Texts to ASCII Codes and Apply the Cross-Correlation Method to Detect the Simple Text Plagiarisms such as Cut-and-paste, term Relocations and etc. WordNet is using to find Similarities to Detect the Plagiarism that uses Synonyms, Translations, Summarizations and etc. The Data set, 2013 Corpus, Provided by PAN Which is the One of Well-known Workshops for Text Plagiarism is used in our Experiments. Our Method are Fourth Ranked Among the Eleven most Outstanding Plagiarism Detection Methods.

Outlier Detection in Time Series Monitoring Datasets using Rule Based and Correlation Analysis Method (규칙기반 및 상관분석 방법을 이용한 시계열 계측 데이터의 이상치 판정)

  • Jeon, Jesung;Koo, Jakap;Park, Changmok
    • Journal of the Korean GEO-environmental Society
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    • v.16 no.5
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    • pp.43-53
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    • 2015
  • In this study, detection methods of outlier in various monitoring data that fit into big data category were developed and outlier detections were conducted for both artificial data and real field monitoring data. Rule-based methods applied rate of change and probability of error for monitoring data are effective to detect a large-scale short faults and constant faults having no change within a certain period. There are however, problems with misjudgement that consider the normal data with a large scale variation as outlier caused by using independent single dataset. Rule-based methods for noise faults detection have a limit to application of real monitoring data due to the problem with a choice of proper window size of data and finding of threshold for outlier judgment. A correlation analysis among different two datasets were very effective to detect localized outlier and abnormal variation for short and long-term monitoring dataset if reasonable range of training data could be selected.

Real-Time Automatic Target Detection in CCD image (CCD 영상에서의 실시간 자동 표적 탐지 알고리즘)

  • 유정재;선선구;박현욱
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.6
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    • pp.99-108
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    • 2004
  • In this paper, a new fast detection and clutter rejection method is proposed for CCD-image-based Automatic Target Detection System. For defence application, fast computation is a critical point, thus we concentrated on the ability to detect various targets with simple computation. In training stage, 1D template set is generated by regional vertical projection and K-means clustering, and binary tree structure is adopted to reduce the number of template matching in test stage. We also use adaptive skip-width by Correlation-based Adaptive Predictive Search(CAPS) to further improve the detecting speed. In clutter rejection stage, we obtain Fourier Descriptor coefficients from boundary information, which are useful to rejected clutters.

Face Detection Based on Distribution Map (분포맵에 기반한 얼굴 영역 검출)

  • Cho Han-Soo
    • Journal of Korea Multimedia Society
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    • v.9 no.1
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    • pp.11-22
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    • 2006
  • Recently face detection has actively been researched due to its wide range of applications, such as personal identification and security systems. In this paper, a new face detection method based on the distribution map is proposed. Face-like regions are first extracted by applying the skin color map with the frequency to a color image and then, possible eye regions are determined by using the pupil color distribution map within the face-like regions. This enables the reduction of space for finding facial features. Eye candidates are detected by means of a template matching method using weighted window, which utilizes the correlation values of the luminance component and chrominance components as feature vectors. Finally, a cost function for mouth detection and location information between the facial features are applied to each pair of the eye candidates for face detection. Experimental results show that the proposed method can achieve a high performance.

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Tsunami-induced Change Detection Using SAR Intensity and Texture Information Based on the Generalized Gaussian Mixture Model

  • Jung, Min-young;Kim, Yong-il
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.34 no.2
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    • pp.195-206
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    • 2016
  • The remote sensing technique using SAR data have many advantages when applied to the disaster site due to its wide coverage and all-weather acquisition availability. Although a single-pol (polarimetric) SAR image cannot represent the land surface better than a quad-pol SAR image can, single-pol SAR data are worth using for disaster-induced change detection. In this paper, an automatic change detection method based on a mixture of GGDs (generalized Gaussian distribution) is proposed, and usability of the textural features and intensity is evaluated by using the proposed method. Three ALOS/PALSAR images were used in the experiments, and the study site was Norita City, which was affected by the 2011 Tohoku earthquake. The experiment results showed that the proposed automatic change detection method is practical for disaster sites where the large areas change. The intensity information is useful for detecting disaster-induced changes with a 68.3% g-mean, but the texture information is not. The autocorrelation and correlation show the interesting implication that they tend not to extract agricultural areas in the change detection map. Therefore, the final tsunami-induced change map is produced by the combination of three maps: one is derived from the intensity information and used as an initial map, and the others are derived from the textural information and used as auxiliary data.

Performance Improvement of Double-talk Detector Using Normalized Error Signal Power (정규화된 오차신호 전력을 이용한 동시통화 검출기의 성능 개선)

  • Heo, Won-Chul;Bae, Keun-Sung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.5C
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    • pp.478-486
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    • 2007
  • Double-talk detection errors can result in either large residual echo or distorting the near-end talker's input speech. Thus accurate double-talk detection is an important problem in the acoustic echo canceller to improve the speech quality. In the double-talk detection algorithm using a cross-correlation coefficient, double-talk detection errors can occur in the initial convergence period of an adaptive filter or in noisy environment since the cross-correlation coefficient becomes large in such situations. In this paper, we propose a new double-talk detection algorithm based on the cross-correlation method using a normalized error signal power to reduce the double-talk detection errors. The experimental results have shown the performance improvement of an acoustic echo canceller as well as the noise-robustness of the proposed double-talk detector.

Color cast detection based on color by correlation and color constancy algorithm using kernel density estimation (색 상관 관계 기반의 색조 검출 및 핵밀도 추정을 이용한 색 항상성 알고리즘)

  • Jung, Jun-Woo;Kim, Gyeong-Hwan
    • Journal of Korea Multimedia Society
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    • v.13 no.4
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    • pp.535-546
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    • 2010
  • Digital images have undesired color casts due to various illumination conditions and intrinsic characteristics of cameras. Since the color casts in the images deteriorate performance of color representations, color correction is required for further analysis of images. In this paper, an algorithm for detection and removal of color casts is presented. The proposed algorithm consists of four steps: retrieving similar image using color by correlation, extraction of near neutral color regions, kernel density estimation, and removal of color casts. Ambiguities in near neutral color regions are excluded based on kernel density estimation by the color by correlation algorithm. The method determines whether there are color casts by chromaticity distributions in near neutral color regions, and removes color casts for color constancy. Experimental results suggest that the proposed method outperforms the gray world algorithm and the color by correlation algorithm.

P wave Detection Algorithm using Cardiologist's Estimation Method (전문가의 추론방법을 이용한 P파 검출 알고리즘)

  • Lee, Gee-Yeon;Hwang, Sung-Oh;Yoon, Young-Ro;Yoon, Hyung-Ro
    • Proceedings of the KOSOMBE Conference
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    • v.1995 no.05
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    • pp.186-189
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    • 1995
  • This paper performed P wave detection algorithm for diagnosis in according to method of cardiologist's P wave detection. We used correlation pattern matching for prominent P waves and P-P interval estimation for ambiguous P waves. Results of this study indicate that this algorithm has potential for improving P wave detection performance.

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