• Title/Summary/Keyword: Measure Detection

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Automatic Edge Detection Method for Mobile Robot Application (이동로봇을 위한 영상의 자동 엣지 검출 방법)

  • Kim Dongsu;Kweon Inso;Lee Wangheon
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.5
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    • pp.423-428
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    • 2005
  • This paper proposes a new edge detection method using a $3{\times}3$ ideal binary pattern and lookup table (LUT) for the mobile robot localization without any parameter adjustments. We take the mean of the pixels within the $3{\times}3$ block as a threshold by which the pixels are divided into two groups. The edge magnitude and orientation are calculated by taking the difference of average intensities of the two groups and by searching directional code in the LUT, respectively. And also the input image is not only partitioned into multiple groups according to their intensity similarities by the histogram, but also the threshold of each group is determined by fuzzy reasoning automatically. Finally, the edges are determined through non-maximum suppression using edge confidence measure and edge linking. Applying this edge detection method to the mobile robot localization using projective invariance of the cross ratio. we demonstrate the robustness of the proposed method to the illumination changes in a corridor environment.

Competition-Based Disparity Detection on the Diffusion-Based Stereo Matching (확산을 이용한 스테레오 정합에서 경쟁적 변이 검출)

  • Lee, Sang-Chan;Kim, Eun-Ji;Seol, Seong-Uk;Nam, Gi-Gon;Kim, Jae-Chang
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.37 no.4
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    • pp.16-25
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    • 2000
  • In this paper, a new disparity detection algorithm which is robust to noise is presented. It detects the disparity of an arbitrary pixel through the iterative competition with neighbor pixels in the range of disparity. A diffusion process to improve stereo matching confidence is used prior to detecting disparity of an arbitrary pixel. It is used for aggregating initial matching measure of the difference map. If the image region for matching is too small, a wrong match might be found due to noise. On the contrary, the region is too big, it results in blurring of object boundaries. Therefore, we decide the image region for matching by using the diffusion process for aggregating matching measure, then detect the true disparity with proposed competition method to the distribution of matching measure. Through the proposed method we get the result of improving matching rate of 6.96% with real stereo imge. From the simulation with the stereo imge, the proposed disparity detection method significantly outperforms the conventional method to matching rate.

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Direction detection technique of radioactive contaminants based on rotating collimator (회전형 콜리메이터 기반 방사능 오염원의 방향탐지 기법)

  • Hwang, Young-Gwan;Song, Keun-Young;Lee, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.11
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    • pp.1519-1527
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    • 2020
  • AGeneral radiation measuring devices have been developed in the form of spatial dose rate detection devices that measure dose rates to radioactive contaminant and 2D or 3D imaging devices for radioactive contamination information. Each of these radiation detection techniques has advantages. The advantages of both detection devices are necessary to minimize personal injury and rapid decontamination in the area of a radioactive accident. In this paper, we proposed a technique that can measure the dose rate and direction information about the radioactive pollutant source in real time using a detection sensor, a rotating body, and a directional shield for radioactive pollutant detection. The rotational-based detection device is configured to check the dose rate and direction using the location information of the rotator and measurement value. We proposed a measurement technique for vertical and horizontal directions through multiple holes. It was confirmed that the measurement error for direction information was less than 1% when detected in the horizontal direction.

Measurement of the Relative Phase Fluctuation by Multiport-Homodyne Detection Method (Multiport-Homodyne 측정 방법에 의한 광신호의 상대적 위상 변화에 대한 연구)

  • 최준홍
    • Proceedings of the Optical Society of Korea Conference
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    • 1990.02a
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    • pp.242-247
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    • 1990
  • By self-homodyne method we measured the relative phase fluctuation of a light wave. Balanced detection system can eliminate local oscillator excess noise and multiport detection makes it possible ot measure the phase change of the signal beam. Deriving the SB(Signal Beam) and the LO(Local Oscillator) from the same laser source, we find the SB maintain constant phase relative to that of the LO. We have introduced a phase fluctuation in the SB by modulating the beam path of the SB. The measured phase fluctuation agreed well with the predicted one, thereby we confirmed the reliability of our system.

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Sharpness-aware Evaluation Methodology for Haze-removal Processing in Automotive Systems

  • Hwang, Seokha;Lee, Youngjoo
    • IEIE Transactions on Smart Processing and Computing
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    • v.5 no.6
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    • pp.390-394
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    • 2016
  • This paper presents a new comparison method for haze-removal algorithms in next-generation automotive systems. Compared to previous peak signal-to-noise ratio-based comparisons, which measure similarity, the proposed modulation transfer function-based method checks sharpness to select a more suitable haze-removal algorithm for lane detection. Among the practical filtering schemes used for a haze-removal algorithm, experimental results show that Gaussian filtering effectively preserves the sharpness of road images, enhancing lane detection accuracy.

PMSM Angle Detection Based on the Edge Field Measurements by Hall Sensors

  • Kim, Jae-Uk;Jung, Sung-Yoon;Nam, Kwang-Hee
    • Journal of Power Electronics
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    • v.10 no.3
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    • pp.300-305
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    • 2010
  • This paper presents a two Hall sensor method for rotor angle detection in permanent magnet synchronous motors (PMSM). To minimize the implementation complexity, the system is designed to measure the edge field of permanent magnet pieces. However, there are nonlinearities in the measured values of the edge field. In this work, an angle correction algorithm is proposed, and the improvements in accuracy are verified through experiments. Finally, a field orientation controller is constructed with the proposed angle detection algorithm.

A Fake-Iris Detection Method using SVDD (단일 클래스 분류기를 이용한 위조 홍채 검출 방법)

  • Lee, Sung-Joo;Kim, Jai-Hie
    • Proceedings of the IEEK Conference
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    • 2007.07a
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    • pp.287-288
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    • 2007
  • In this paper, we propose a fake-iris detection method. In order to detect the fake-iris, we measure physiological features which are the reflectance ratio of the iris to the sclera at 750 nm and that at 850nm. In order to classify live and fake iris features, we use support vector data description (SVDD). From our experimental results, it is clear that our fake-iris detection method achieves high performance when distinguishing between a live-iris and a fake-iris.

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Robust Pupil Detection using Rank Order Filter and Cross-Correlation (Rank Order Filter와 상호상관을 이용한 강인한 눈동자 검출)

  • Jang, Kyung-Shik;Park, Sung-Dae
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.7
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    • pp.1564-1570
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    • 2013
  • In this paper, we propose a robust pupil detection method using rank order filter and cross-correlation. Potential pupil candidates are detected using rank order filter. Eye region is binarized using variable threshold to find eyebrow, and pupil candidates at the eyebrow are removed. The positions of pupil candidates are corrected, the pupil candidates are grouped into pairs based on geometric constraints. A similarity measure is obtained for two eye of each pair using cross-correlation, we select a pair with the largest similarity measure as a final pupil. The experiments have been performed for 500 images of the BioID face database. The results show that it achieves the high detection rate of 96.8% and improves about 11.6% than existing method.

Image-based Subway Security System by Histogram Projection Technology

  • Bai, Zhiguo;Jung, Sung-Hwan
    • Journal of Korea Multimedia Society
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    • v.18 no.3
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    • pp.287-297
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    • 2015
  • A railway security detection system is very important. There are many safety factors that directly affect the safe operation of trains. Security detection technology can be divided into passive and active approaches. In this paper, we will first survey the railway security systems and compare them. We will also propose a subway security detection system with computer vision technology, which can detect three kinds of problems: the spark problem, the obstacle problem, and the lost screw problem. The spark and obstacle detection methods are unique in our system. In our experiment using about 900 input test images, we obtained about a 99.8% performance in F- measure for the spark detection problem, and about 94.7% for the obstacle detection problem.