• Title/Summary/Keyword: cross correlation analysis

검색결과 1,313건 처리시간 0.03초

2단계 스테레오 정합기법을 이용한 DEM 추정 (DEM Estimation Using Two Stage Stereo Matching Method)

  • 남창우;우동민
    • 대한전기학회논문지:시스템및제어부문D
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    • 제49권12호
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    • pp.659-666
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    • 2000
  • A stereo matching has been an important tool for reconstructing three dimensional terrain. By using stereo matching technique, DEM(Digital Elevaton Map) can be generated by the disparity from a reference image to a target image. Generally disparity map can be evaluated by matching the reference image to the target image and if the role of the reference and the target are interchanged, a different DEM can be obtained. In this paper, we propose a new fusion technique to estimate the optimal DEM by eliminating the false DEM due to occlusion. To detect the false DEM, we utilize two measure of accuracy: self-consistency and cross-correlation score. We test the effectiveness of the proposed methods with a quantitative analysis using simulated images. Experimental result indicate that the proposed methods show 24.4% and 33.1% improvement over either DEM.

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A Study on the Acoustic Fault Detection System of Insulators from Their Radiation Noises

  • Park, Kyu-Chil;Yoon, Jong-Rak
    • Journal of information and communication convergence engineering
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    • 제9권5호
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    • pp.510-514
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    • 2011
  • To detect the insulator in the fault state on the electric poles, we first measured radiation sounds from normal state insulators and error state insulators in the anechoic chamber. We processed the signals in frequency domain to find the features with filter bank, narrow band and wide band analysis. So we could found two apparent results from their frequency spectrums - one was 120Hz harmonic components, the other was high average noise level than normal state ones. Then we also introduced a technique for the direction detection of the fault state insulator using the cross correlation from the three dimensional array microphones. To eliminate the noise signal from unexpected directions, we suggested the zero padding technique in cross correlation function. From these, we could conclude that acoustic fault detection techniques are useful of the detection of insulators' faults and the estimation of the direction of the fault state insulators.

Holographic Quantitative Structure-Activity Relationship (HQSAR) Study of 3,4-Dihydroxychalcone Derivatives as 5-Lipoxygenase Inhibitors

  • Gadhe, Changdev G.
    • 통합자연과학논문집
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    • 제4권3호
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    • pp.210-215
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    • 2011
  • Holographic quantitative structure-activity relationships (HQSAR) is a useful tool to correlates structures with their biological activities. HQSAR is a two dimensional (2D) QSAR methodology, which generates QSAR equations through 2D fingerprint and correlates it with biological activity. Here, we report a 2D-QSAR model for a series of fifty-one 3,4-dihydroxychalcones derivatives utilizing HQSAR methodology. We developed HQSAR model with 6 optimum numbers of components (ONC), which resulted in cross-validated correlation coefficient ($q^2$) of 0.855 with 0.283 standard error of estimate (SEE). The non-cross-validated correlation coefficient (r2) with 0.966 indicates the model is predictive enough for analysis. Developed HQSAR model was binned in to a hologram length of 257. Atomic contribution map revealed the importance of dihydroxy substitution on phenyl ring.

걸음걸이 인식을 위한 지배 요소 분석 (Analysis on Dominant Factor for Gait Recognition)

  • 박한훈;박종일
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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    • pp.321-324
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    • 2003
  • This paper presents a novel system that analyzes and recognizes a gait based on shape context on silhouette images. The main functions of the system consist of three steps: First, the system extracts the silhouette images from galt image sequence by performing a simple pre-processing and acquires the AGM(Averaged Gait Map) by averaging them. Next. it computes the cross-correlation between the AGMs. Finally, it classifies the AGMs based on the cross-correlation using nearest neighborhood classification. The proposed system uses two cues to classify a gait: One corresponds to biometric shape cue such as body height width. and body-part proportions. The other corresponds to gait cue such as stride length and amount of arm swing. Perceptionally, the biometric cues are sailent on the double support (both legs spread and touching the ground) while the gait cues on the midstance. Through a variety of experiments, it is proved that the property of a gait is mainly influenced by gait cues than biometric cues.

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3차원 실시간 디지털 스페클 토모그래피를 이용한 부탄 밀도 분포 분석 (Analysis of Density Distribution for Butane Using Three-dimentional and Real-time Digital Speckle Tomography)

  • 고한서;박광희;김용재
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.1789-1794
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    • 2003
  • Transient and asymmetric density distributions have been investigated by digital speckle tomography. Multiple CCD images captured movements of speckles in three angles of view simultaneously because the flows were asymmetric and transient. The speckle movements between no flow and downward butane flow from a circular half opening have been calculated by a cross-correlation tracking method so that those distances can be tranferred to deflection angles of laser rays for density gradients. The three-dimensional density fields have been reconstructed from the fringe shift by a real-time multiplicative algebraic reconstruction technique (MART).

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절연전선 결함 위치 추정에 대한 시간-주파수 영역 반사파 계측법의 적용 (Estimation of Fault Location on a Power Line using the Time-Frequency Domain Reflectometry)

  • 두승호;곽기석;박진배
    • 전기학회논문지
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    • 제57권2호
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    • pp.268-275
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    • 2008
  • In this paper, we introduce a new method for detecting and estimating faults on a power line using the time-frequency domain reflectometry system. The system rests upon time-frequency signal analysis and uses a chirp signal which is multiplied by Gaussian envelope. The chirp signal is used as a reference signal, and we can get the reflected signal from a fault on a wire. To detect and estimate faults, we analyze the reflected signal by Wigner time-frequency distribution function and normalized time-frequency cross correlation function. In this paper we design an optimal reference signal for power line and implement a system for estimating fault distance on a power line with the TFDR implemented by PXI equipments. This approach is verified by some experiments with HIV 2.25mm power lines.

PIV 가시화에 의한 합류덕트에서의 유동특성 (Flow Characteristics for PIV Visualization at Junction Duct)

  • 김명관;권오붕;배대석
    • 동력기계공학회지
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    • 제9권4호
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    • pp.45-50
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    • 2005
  • Characteristics of flows at T-junction duct with and without orifices are investigated in this paper. Experiments and PIV visualization were carried out for several flow rates. Two-dimensional PIV experimental apparatus was decided by numerical analysis. PIV visualization was also coded to visualize flow fields at junctions for two-dimensional case. For the PIV visualization system, Grey-Level Cross-Correlation particle tracking algorithm was used to calculate the flow fields. Vinyl chloride polymer particles of $100{\sim}150{\mu}m$ of diameter are used in this visualization. The PIV visualization results showed relatively good agreement with Experimental data.

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PIV 성능시험을 위한 표준실험장치 개발 (Development of Standard Experimental Apparatus for PIV Performance Evaluation)

  • 성재용;도덕희;이석종;황태규
    • 한국가시화정보학회지
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    • 제4권2호
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    • pp.37-43
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    • 2006
  • An experimental apparatus for PIV performance evaluation has been developed. Stardard uncertainty of a two-dimensional cross-correlation PIV system was investigated based upon the standard experimental apparatus, which was devised to model the rigid body rotating flows. For the systematic analysis of the uncertainty introduced by each component (algorithm, CCD camera, frame grabber) of the PIV system, standard images are fed into the component independently. The standard experiments show that 53% of the uncertainty in the present PIV system results from the frame grabber but the errors from the algorithm and digital camera are ignorable.

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GMW 수열과 No 수열에 의해서 생성된 이진 수열 분석 (Analysis of binary sequences generated by GMW sequences and No sequences)

  • 조성진;임지미
    • 한국정보통신학회논문지
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    • 제15권10호
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    • pp.2181-2187
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    • 2011
  • 본 논문에서는 GMW 수열과 No 수열에 의해서 생성된 이진 수열들의 집합을 소개하고 분석한다. 집합안의 각 수열들은 주기 $N=2^n-1$이고 n=2m 이며 $2^m$개의 수열들이 있다. 합성된 수열의 자기상관계수와 상호상관계수 그리고 선형스팬을 구한다.

QSAR Studies on 6-Nitroquipazine Analogues as Serotonin Transporter

  • Lee, In-Young;Lee, Kyung-A;Lee, Bon-Su;Chi, Dae-Yoon;Kim, Chan-Kyung
    • Bulletin of the Korean Chemical Society
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    • 제27권12호
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    • pp.1969-1975
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    • 2006
  • 3D-QSAR model that correlates the biological activities with the chemical structures of quipazine derivatives acting on the serotonine transporter (SERT) was developed by comparative molecular field analysis (CoMFA). Total 8 models were constructed and a more accurate model, using close 1 $\AA$ grid spacing and StDev*Coefficients weight value gave better results. The contour maps with the best model, the resulting cross-validated correlation ($q^2$ : 0.744), and non-cross-validated correlation ($r^2$ : 0.966) indicate the steric and electrostatic environment of inhibitors in the SERT binding pocket. This study can be used as a putative picture of the pharmacophore in the design of novel and potent inhibitors.