• Title/Summary/Keyword: correlation algorithm

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A broadband detection algorithm using cross-correlation of two split beams for cylindrical array sonar (원통형 배열 소나를 위한 두 개의 분리 빔의 상호상관을 이용한 광대역탐지 기법)

  • Kwak, ChulHyun
    • The Journal of the Acoustical Society of Korea
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    • v.36 no.5
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    • pp.300-304
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    • 2017
  • In a cylindrical sonar, a conventional broadband energy detector has limitations in the separation of adjacent targets. In this paper, a broadband detection algorithm using cross-correlation is applied to the cylindrical sonar to improve the bearing resolution. The proposed algorithm uses split beamforming before broadband detection processing using cross-correlation to generate half beams. The time delay obtained from the peak of correlation between half beams is used to estimate the bearing of target. Simulations demonstrate the improved performance of the proposed algorithm against the conventional algorithm.

Pan Evaporation Modeling using Cascade-Correlation Algorithm (Cascade-Correlation Algorithm을 이용한 증발접시 증발량의 모형화)

  • Kim, Seong-Won
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.05b
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    • pp.766-770
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    • 2005
  • Cascade-Correlation Neural Networks Model(CCNNM) is used to estimate daily evaporation using limited climatical variables such as atmospheric temperature, dewpoint temperature, relative humidity, wind speed, sunshine duration and radiation. DeBruln equation is applied to estimate daily free-surface evaporation. It is converted into pan evaporation using pan coefficient. The results of CCNNM shows better than those of Debruin equation. This research represents that the strong nonlinear relationship such as evaporation modeling can be generalized by the CCNNM ; a special type of Backpropagation algorithm Neural Networks Model.

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AN ANALYSIS OF THE AUTOMATCHING USING LANDSAT TM DATA AND ASTRONOMICAL APROACH (LANDSAT TM 자료를 사용한 AUTOMATCHING ALGORITHM의 분석 및 천문학 연구 분야로서의 제안)

  • 박종현;최규홍;조성의;박경윤
    • Journal of Astronomy and Space Sciences
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    • v.8 no.1
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    • pp.115-123
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    • 1991
  • Automatching algorithm is suitable for cross-correlation, which showed correlation surface about maximal correlation coefficient. The size of the window area must be determined empirically, whereas window size generally chosen as a compromise between speed and accuracy. It is possible that epipolar transform prevented from mismatching and decreased search space. In application of the astronomical fields, automatching algorithm mainly used to planet surface recovery in satellite image.

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Robust System Identification Algorithm Using Cross Correlation Function

  • Takeyasu, Kazuhiro;Amemiya, Takashi;Goto, Hiroyuki;Masuda, Shiro
    • Industrial Engineering and Management Systems
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    • v.1 no.1
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    • pp.79-86
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    • 2002
  • This paper proposes a new algorithm for estimating ARMA model parameters. In estimating ARMA model parameters, several methods such as generalized least square method, instrumental variable method have been developed. Among these methods, the utilization of a bootstrap type algorithm is known as one of the effective approach for the estimation, but there are cases that it does not converge. Hence, in this paper, making use of a cross correlation function and utilizing the relation of structural a priori knowledge, a new bootstrap algorithm is developed. By introducing theoretical relations, it became possible to remove terms, which is liable to include much noise. Therefore, this leads to robust parameter estimation. It is shown by numerical examples that using this algorithm, all simulation cases converge while only half cases succeeded with the previous one. As for the calculation time, judging from the fact that we got converged solutions, our proposed method is said to be superior as a whole.

Automatic Correlation Generation using the Alternating Conditional Expectation Algorithm

  • Kim, Han-Gon;Kim, Byong-Sup;Cho, Sung-Jae
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.05a
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    • pp.292-297
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    • 1997
  • An alternating conditional expectation (ACE) algorithm, a kind of non-parametric regression method, is proposed to generate empirical correlations automatically. The ACE algorithm yields an optimal relationship between a dependent variable and multiple independent variables without any preprocessing and initial assumption on the functional forms. This algorithm is applied to a collection of 12,879 CHF data points for forced convective boiling hi vertical tubes to develop a new critical heat flux (CHF) correlation. The meat root mean square, and maximum errors of our new correlation are -0.558%, 12.5%, and 122.6%, respectively. Our CHF correlation represents the entire set of CHF data with an overall accuracy equivalent to or better than that of three existing correlations.

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A Desired Signal Estimation using Sub-Array Algorithm of Adaptive Array Antenna in Correlation Channel Environment (상관성 채널 환경에서의 적응배열안테나의 부배열 알고리즘을 이용한 관심신호 추정)

  • Lee, Kwanhyeong;Cho, Taejun
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.13 no.3
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    • pp.75-81
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    • 2017
  • This paper estimate a desired signal in a correlation wireless communication. The transmitted signal is mixed with the information signal, interference, and noise in wireless channel, and it is incident on the receiver. In this paper, we apply MUSIC algorithm and sub-array method to recover the total rank of the correlation matrix in order to estimation a desired signal among receiving signals. Through simulation, we analyze to compare the proposed method with the classical MUSIC algorithm. As a result of the simulation, the proposed method improved the resolution about 10degrees compared to the conventional MUSIC algorithm. We prove the superiority of the proposed method for the desired signal estimation in correlation channel.

Terrain reference navigation algorithm based on cross-correlation matching using topography characteristics (지형의 특성을 이용한 상호상관정합 기반 지형참조항법 알고리즘)

  • Lee, Bo-Mi;Kwon, Jay-Hyoun
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2010.04a
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    • pp.161-164
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    • 2010
  • The study on terrain referenced navigation has been proceeded from 1940s in advanced country with the object of military. In this study, the analysis regarding algorithm developed using cross-correlation matching algorithm and extended Kalman filter and simulation will be introduced. As a result, the standard deviation of position error from cross-correlation matching algorithm has been calculated 34.3m. It meant that the result has stable accuracy on the navigation. However, further study on terrain referenced navigation based on analysis of various topographic characteristics should be performed.

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A Study on DOA and Delay Time Presumption based on Average Method (평균방법에 근거한 DOA와 지연시간추정에 관한 연구)

  • 이관형;송우영
    • Journal of the Korea Society for Simulation
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    • v.13 no.2
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    • pp.1-12
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    • 2004
  • This paper estimated the arrival angle and electric wave delay time using the space method law and the directions of arrival (DOA) estimation algorithm in case of signal correlation. Space method law is the method used to repress cross correlation before applying the weight value to the receiving signal. The values of the diagonal elements in the correlation matrix were averaged to replace as the diagonal elements value. In the area of wireless communication or mobile communication, there are high correlations in case of low delay time difference in multiple waves. This causes the quality of the communication to drop due to interference with the desired signal elements. This paper estimated the arrival angle and electric wave delay time using the space method law and the MUSIC algorithm. With the arrival angle algorithm, the arrival angle cannot be estimated below 5 in case of signal correlations because the angle resolution capacity decreases accordingly. The super resolution capacity was estimated to determine the arrival angle below 5 in this paper. In addition, the proposed algorithm estimated the short delay time difference to be below 20ns.

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Two Wheeler Recognition Using the Correlation Coefficient for Histogram of Oriented Gradients to Apply Intelligent Wheelchair (지능형 휠체어 적용을 위한 기울기 히스토그램의 상관계수를 이용한 도로위의 이륜차 인식)

  • Kim, Bum-Koog;Park, Sang-Hee;Lee, Yeung-Hak;Lee, Gang-Hwa
    • Journal of Biomedical Engineering Research
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    • v.32 no.4
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    • pp.336-344
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    • 2011
  • This article describes a new recognition algorithm using correlation coefficient for intelligent wheelchair to avoid collision for elderly or disabled people. The correlation coefficient can be used to represent the relationship of two different areas. The algorithm has three steps: Firstly, we extract an edge vector using the Histogram of Oriented Gradients(HOG) which includes gradient information and unique magnitude for each cell. From this result, the correlation coefficients are calculated between one cell and others. Secondly, correlation coefficients are used as the weighting factors for normalizing the HOG cell. And finally, these features are used to classify or detect variable and complicated shapes of two wheelers using Adaboost algorithm. In this paper, we propose a new feature vectors which is calculated by weighted cell unit to classify with multiple view-based shapes: frontal, rear and side views($60^{\circ}$, $90^{\circ}$ and mixed angle). Our experimental results show that two wheeler detection system based on a proposed approach leads to a higher detection accuracy than the method using traditional features in a similar detection time.

A Fast MSRCR Algorithm Using Hierarchical Discrete Correlation (HDC를 이용한 고속 MSRCR 알고리즘)

  • Han, Kyu-Phil
    • Journal of Korea Multimedia Society
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    • v.13 no.11
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    • pp.1621-1629
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    • 2010
  • This paper presents an improved fast MSRCR algorithm that MSRs are commonly adopted at tone mapping in color vision. Conventional MSRs consist of three SSRs, which use three Gaussian functions with different scales as those surround ones. This convolution processes require much computation load. Therefore, the proposed algorithm adopts a hierarchical discrete correlation which is equivalent to Gaussian function and the Retinex process is only applied to the luminance channel in order to get a fast processing. A simple color preservation scheme is applied to the Retinex output from the luminance channel in the proposed MSRCR algorithm. Experimental results show that the proposed algorithm required less number of oprations and computation time about 1/9.5 and 1/3.5 times, respectively, than those of the simplest MSR and was equivalent to conventional MSRs.