• Title/Summary/Keyword: shape detection

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A STUDY ON 3D STRUCTURE DETECTION FOR FOREST TREES USING REFLECTED SPECTRUM INFORMATION

  • Ono, Yuhsaku;Kajiwara, Koji;Honda, Yoshiaki
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.345-348
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    • 2007
  • This research aimed at developing a technique for estimating the tree height using BRF (Bi-directional Reflectance Factor) through the clarification of the relation between shape of the tree crown and the tree height and the relations between the shape of the tree crown and BRF. This paper, reports the results of analyses of data acquired by field measurements done to clarify relation between crown shape and tree height.

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Line Detection Using Log Hough Transform (Log-Hough 변환을 이용한 직선검출)

  • 정헌상;황의봉
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.13 no.3
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    • pp.118-123
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    • 1999
  • Hough transform is well employed to retect or recognize the lines in image processing or in computer vision. Curve of the logarithm of ranges against the bearing does not change its shape according to data trints. This fact suggests that calculation cost can be remarkably reduced. An effective line detection algorithm is represented.sented.

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The Development of Flaw Detection in Concrete by the Impact-Echo Testing Method (충격탄성파법을 이용한 콘크리트 내부의 결함탐상 기술개발)

  • 박선균;임창덕
    • Proceedings of the Korea Concrete Institute Conference
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    • 1991.04a
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    • pp.105-110
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    • 1991
  • The conventional high-frequency testing method is difficult to detect flaw in concrete because the high frequency stress wave is strongly attenuated due to the large grain size and heterogeneous structure. For restoration of this problem, we develop the stu요 of flaw detection in large concrete block containing various artificial flaws by low frequency spectrum anlysis of impact-echo waveforms. This impact-echo testing method is possible to determine the flaw size, shape and location in large concrete block even if required some attention in case of containing reinforcing steel bar.

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Inductive Sensor and Target Board Design for Accurate Rotation Angle Detection

  • Hwang, Jae-Jeong;Moon, Joon
    • International Journal of Internet, Broadcasting and Communication
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    • v.9 no.1
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    • pp.64-70
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    • 2017
  • In the commercial building such as huge enterprise building, more accurate operation of the center-controlled roller blind. We design, in this work, the target disc that its shape is nonlinearly changing and the sensor coils that are differentially arranged. The performance shows less than 1% accuracy when it is implemented in the roller blind.

Linear Feature Detection of Rectangular Object Area using Edge Tracing-based Algorithm (에지 트레이싱 기법을 이용한 사각형 물체의 선형 특징점 검출)

  • 오중원;한희일
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.2092-2095
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    • 2003
  • In this paper, we propose an algorithm to extract rectangular object area such 3s Data Matrix two-dimensional barcode using edge tracing-based linear feature detection. Hough transform is usually employed to detect lines of edge map. However, it requires parametric image space, and does not find the location of end points of the detected lines. Our algorithm detects end points of the detected lines using edge tracing and extracts object area using its shape information.

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Local Feature Detection on the Ocular Fundus Fluorescein angiogram Using Relaxation Process (이완법을 이용한 형광안저화상의 국소특징 검출)

  • 高昌林
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.5
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    • pp.856-862
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    • 1987
  • An local adaptive image segmentatin algorithm for local feature detection and effective clustering of unimodal histogram shape are proposed. Local adaptive difference image and its histogram are obtained from the input image. The parameters are derived from the histogram and used for the segmentation based on relaxatin process. The results showed effective region segmentation and good noise cleaning for the ocular fundus fluorescein angiogram which has low contrast and unimodal histogram.

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Multiple Peak Detection Using the Extended Fuzzy Clustering (확장된 퍼지 클러스터링 알고리즘을 이용한 다중 첨두 검출)

  • 김수환;조창호;강경진;이태원
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.29B no.1
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    • pp.102-112
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    • 1992
  • We have already proposed an extended fuzzy clustering algorithm which considers the importance of the data to be classified in a previous paper. In this paper, we suggest the extended fuzzy clustering algorithm based new method to slove a multiple peak detection problem, and prove experimently that this algorithm can detect the multiple peak adaptively to the noise and the shape of peaks.

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A direct damage detection method using Multiple Damage Localization Index Based on Mode Shapes criterion

  • Homaei, F.;Shojaee, S.;Amiri, G. Ghodrati
    • Structural Engineering and Mechanics
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    • v.49 no.2
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    • pp.183-202
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    • 2014
  • A new method of multiple damage detection in beam like structures is introduced. The mode shapes of both healthy and damaged structures are used in damage detection process (DDP). Multiple Damage Localization Index Based on Mode Shapes (MDLIBMS) is presented as a criterion in detecting damaged elements. A finite element modeling of structures is used to calculate the mode shapes parameters. The main advantages of the proposed method are its simplicity, flexibility on the number of elements and so the accuracy of the damage(s) position(s), sensitivity to small damage extend, capability in prediction of required number of mode shapes and low sensitivity to noisy data. In fact, because of differential and comparative form of MDLIBMS, using noise polluted data doesn't have major effect on the results. This makes the proposed method a powerful one in damage detection according to measured mode shape data. Because of its flexibility, damage detection process in multi span bridge girders with non-prismatic sections can be done by this method. Numerical simulations used to demonstrate these advantages.

Multiple Plane Area Detection Using Self Organizing Map (자기 조직화 지도를 이용한 다중 평면영역 검출)

  • Kim, Jeong-Hyun;Teng, Zhu;Kang, Dong-Joong
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.1
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    • pp.22-30
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    • 2011
  • Plane detection is very important information for mission-critical of robot in 3D environment. A representative method of plane detection is Hough-transformation. Hough-transformation is robust to noise and makes the accurate plane detection possible. But it demands excessive memory and takes too much processing time. Iterative randomized Hough-transformation has been proposed to overcome these shortcomings. This method doesn't vote all data. It votes only one value of the randomly selected data into the Hough parameter space. This value calculated the value of the parameter of the shape that we want to extract. In Hough parameters space, it is possible to detect accurate plane through detection of repetitive maximum value. A common problem in these methods is that it requires too much computational cost and large number of memory space to find the distribution of mixed multiple planes in parameter space. In this paper, we detect multiple planes only via data sampling using Self Organizing Map method. It does not use conventional methods that include transforming to Hough parameter space, voting and repetitive plane extraction. And it improves the reliability of plane detection through division area searching and planarity evaluation. The proposed method is more accurate and faster than the conventional methods which is demonstrated the experiments in various conditions.

A person detection in HEVC bitstream domain based on bits density feature and YOLOv3 framework

  • Wiratama, Wahyu;Sim, Donggyu
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2019.11a
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    • pp.169-171
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    • 2019
  • This paper proposes an algorithm to detect persons in bitstream domain by skipping a reconstruction picture process in HEVC decoding. A new 3-channel feature extraction map is introduced in this paper by modelling the relationship between bits per CU density, average PU shape in CU, and total transform coefficients in CU from syntax elements. A state-of-the-art of YOLOv3 detection algorithm is used to detect and localize person on extracted feature maps. Based on the experimental results, the proposed person detection framework can achieve mAP of 0.68 and be able to find persons on feature maps. In addition, the proposed person detection can save decoding time about 60% by removing reconstruction picture process.

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