• Title/Summary/Keyword: Local Maxima

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Key Frame Detection and Multimedia Retrieval on MPEG Video (MPEG 비디오 스트림에서의 대표 프레임 추출 및 멀티미디어 검색 기법)

  • 김영호;강대성
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2000.08a
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    • pp.297-300
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    • 2000
  • 본 논문에서는 MPEG 비디오 스트림을 분석하여 DCT DC 계수를 추출하고 이들로 구성된 DC 이미지로부터 제안하는 robust feature를 이용하여 shot을 구하고 각 feature들의 통계적 특성을 이용하여 스트림의 특징에 따라 weight를 부가하여 구해진 characterizing value의 시간변화량을 구한다. 구해진 변화량의 local maxima와 local minima는 MPEG 비디오 스트림에서 각각 가장 특징적인 frame과 평균적인 frame을 나타낸다. 이 순간의 frame을 구함으로서 효과적이고 빠른 시간 내에 key frame을 추출한다. 추출되어진 key frame에 대하여 원영상을 복원한 후, 색인을 위하여 다수의 parameter를 구하고 사용자가 질의한 영상에 대해서 이들 파라메터를 구하여 key frame들과 가장 유사한 대표영상들을 검색한다.

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Wavelet Generation and It's Application in Gravity Potential (중력 포텐셜에서의 웨이브렛 생성과 응용)

  • Kim, Sam-Tai;Jin, Hong-Sung;Rim, Hyoung-Rae
    • Journal of the Korean earth science society
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    • v.25 no.2
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    • pp.109-114
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    • 2004
  • A wavelet method is applied to the analysis of gravity potential. One scaling function is proposed to generate wavelet. The scaling function is shown to be replaced to the Green’s function in gravity potential. The upward continuation can be expressed as a wavelet transform i.e. convolution with the scaling function. The scaling factor indicates the height variation. The multiscale edge detection is carried by connecting the local maxima of the wavelet transform at scales. The multiscale edge represents discontinuity of the geological structure. The multiscale edge method is applied to gravity data from Masan and Changwon.

Identification of WAT1-like genes in Panax ginseng and functional analysis in secondary growth

  • Hong, Jeongeui;Ryu, Hojin
    • Journal of Plant Biotechnology
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    • v.49 no.3
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    • pp.171-177
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    • 2022
  • The precise homeostatic regulation of local auxin accumulation in xylem precursors of cambium stem cell tissues is one of the most important mechanisms for plant vascular patterning and radial secondary growth. Walls are thin (WAT1), a novel intracellular auxin transporter, contributes directly to the auxin accumulation maxima in xylem precursors. According to recent research, the auxin signaling activated pathway-related gene network was significantly enriched during the secondary growth of Panax ginseng storage roots. These imply that during P. ginseng root secondary growth, specific signaling mechanisms for local auxin maxima in the vascular cambial cells are probably triggered. This study identified four WAT1-like genes, PgWAT1-1/-2 and PgWAT2-1/-2, in the P. ginseng genome. Their expression levels were greatly increased in nitratetreated storage roots stimulated for secondary root growth. PgWAT1-1 and PgWAT2-1 were similar to WAT1 from Arabidopsis and tomato plants in terms of their subcellular localization at a tonoplast and predicted transmembrane topology. We discovered that overexpression of PgWAT1-1 and PgWAT2-1 was sufficient to compensate for the secondary growth defects observed in slwat1-copi loss of function tomato mutants. This critical information from the PgWAT1-1 and PgWAT2-1 genes can potentially be used in future P. ginseng genetic engineering and breeding for increased crop yield.

Minimizing Algorithm of Baseline Wander for ECG Signal using Morphology-pair (Morphology-pair를 이용한 심전도 신호의 기저선 변동 잡음 제거 알고리즘)

  • Kim, Sung-Wan;Kim, Se-Yun;Kim, Tae-Hun;Choi, Byung-Jae;Park, Kil-Houm
    • Journal of the Korean Institute of Intelligent Systems
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    • v.20 no.4
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    • pp.574-579
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    • 2010
  • The baseline wander is most fatal noise, because it obstructs reliable diagnosis of cardiac disorder. Thus, in this paper, the morphology-pair is proposed for estimation of baseline wander except P, T-wave and QRS-complex. Proposed Morphology-pair is able to except P, R, T-wave which have characteristics of local maxima. Likewise Q, S-wave such as local minima are excepted by proposed Morphology-pair. The final baseline wander eliminated ECG signal is deducted by subtraction of original ECG and estimated baseline wander. The experimental results based on the MIT/BIH database show that the proposed algorithms produce promising results.

VARIATION OF LOCAL POOL BOILING HEAT TRANSFER COEFFICIENT ON 3-DEGREE INCLINED TUBE SURFACE

  • Kang, Myeong-Gie
    • Nuclear Engineering and Technology
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    • v.45 no.7
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    • pp.911-920
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    • 2013
  • Experimental studies on both subcooled and saturated pool boiling of water were performed to obtain local heat transfer coefficients on a $3^{\circ}$ inclined tube of 50.8 mm diameter at atmospheric pressure. The local values were determined at every $45^{\circ}$ from the very bottom to the uppermost of the tube periphery. The maximum and minimum local coefficients were observed at the azimuthal angles of $0^{\circ}$ and $180^{\circ}$, respectively, in saturated water. The locations of the maxima and the minima were dependent on the inclination angle of the tube as well as the degree of subcooling. The major heat transfer mechanisms were considered to be liquid agitation generated by the sliding bubbles and the creation of big size bubbles through bubble coalescence. As a way of quantifying the heat transfer coefficients, an empirical correlation was suggested.

Retrieval System Adopting Statistical Feature of MPEG Video (MPEG 비디오의 통계적 특성을 이용한 검색 시스템)

  • Yu, Young-Dal;Kang, Dae-Seong;Kim, Dai-Jin
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.38 no.5
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    • pp.58-64
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    • 2001
  • Recently many informations are transmitted ,md stored as video data, and they are on the rapid increase because of popularization of high performance computer and internet. In this paper, to retrieve video data, shots are found through analysis of video stream and the method of detection of key frame is studied. Finally users can retrieve the video efficiently. This Paper suggests a new feature that is robust to object movement in a shot and is not sensitive to change of color in boundary detection of shots, and proposes the characterizing value that reflects the characteristic of kind of video (movie, drama, news, music video etc,). The key frames are pulled out from many frames by using the local minima and maxima of differential of the value. After original frame(not de image) are reconstructed for key frame, indexing process is performed through computing parameters. Key frames that arc similar to user's query image arc retrieved through computing parameters. It is proved that the proposed methods are better than conventional method from experiments. The retrieval accuracy rate is so high in experiments.

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Fundamental Frequency Estimation of Voiced Speech Signals Based on the Inflection Point Detection (변곡점 검출에 기반한 음성의 기본 주파수 추정)

  • Byeonggwan Iem
    • Journal of IKEEE
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    • v.27 no.4
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    • pp.472-476
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    • 2023
  • Fundamental frequency/pitch period are major characteristics of speech signals. They are used in many speech applications like speech coding, speech recognition, speaker identification, and so on. In this paper, some of inflection points are used to estimate the pitch which is the inverse of the fundamental frequency. The inflection points are defined as points where local maxima, local minima or the slope changes occur. The speech signal is preprocessed to remove unnecessary inflection points due to the high frequency components using a low pass filter. Only the inflection points from local maxima are used to get the pitch period. While the existing pitch estimation methods process speech signals in blockwise, the proposed method detects the inflection points in sample and produces the pitch period/fundamental frequency estimates along the time. Computer simulation shows the usefulness of the proposed method as a fundamental frequency estimator.

Small Target Detection in Multi-Resolution Image Using Facet Model (다중 해상도 영상에서 페이싯 모델을 이용한 초소형 표적 검출)

  • Park, Ji-Hwan;Lee, Min-Woo;Lee, Chul-Hun;Joo, Jae-Heum;Nam, Ki-Gon
    • Journal of the Institute of Convergence Signal Processing
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    • v.12 no.2
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    • pp.76-82
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    • 2011
  • In this paper, we propose the technique to detect the location and size of the small target in multi-resolution image using cubic facet model. The input image is reduced by the multi-resolution and we obtain the multi-resolution images. We apply the facet model and the local maxima conditions to the multi-resolution images of each level. And then, we detect the location of the small target. We estimate that the location at the maximum of the $D_2$ which means the local maxima value of the facet model in the multi-resolution images is the location of the small target. We can detect the small target of the various size about the multi-resolution images of each level. In this paper, we experimented in the various infrared images with the small target. The method using the typical facet model applies a mask. However, the proposed method applies a mask in the multi-resolution images. We verified to vary the mask size and differ the size of the small target. The proposed algorithm can detect the location and size of the small target.

Point Cloud Classification Method for Mountainous Area (산악지역 점군자료 분류기법 연구)

  • Choi, Yun-Woong;Lee, Geun-Sang;Cho, Gi-Sung
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2010.04a
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    • pp.387-388
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    • 2010
  • There is no generalized and systematic method yet to data pre-processing for point cloud data classification even if there have been lots of previous studies such as local maxima filter, morphology filter, slope based filter and so on. Main focus of this study is to present classification method for bare ground information from LiDAR data for the mountainous area.

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