• Title/Summary/Keyword: distance transform

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A Study on Scale-Invariant Features Extraction and Distance Measurement for Localization of Mobile Robot (이동로봇의 위치 추정을 위한 스케일 불변 특징점 추출 및 거리 측정에 관한 연구)

  • Jung, Dae-Seop;Jang, Mun-Suk;Ryu, Je-Goon;Lee, Eung-Hyuk;Shim, Jae-Hong
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.625-627
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    • 2005
  • Existent distance measurement that use camera is method that use both Stereo Camera and Monocular Camera, There is shortcoming that method that use Stereo Camera is sensitive in effect of a lot of expenses and environment variables, and method that use Monocular Camera are big computational complexity and error. In this study, reduce expense and error using Monocular Camera and I suggest algorithm that measure distance, Extract features using scale Invariant features Transform(SIFT) for distance measurement, and this measures distance through features matching and geometrical analysis, Proposed method proves measuring distance with wall by geometrical analysis free wall through feature point abstraction and matching.

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Hough Transform-based Semi-automatic Vertex Detection Algorithm on a Touch Screen Mobile Phone (모바일 폰 터치스크린에서 허프변환 기반의 반자동식 정점 검출 알고리즘)

  • Jang, Young-Kyoon;Woo, Woon-Tack
    • Journal of KIISE:Computing Practices and Letters
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    • v.16 no.5
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    • pp.596-600
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    • 2010
  • This paper proposes hough transform-based semi-automatic vertex detection algorithm for object modeling on a mobile phone supporting touch-screens. The proposed algorithm shows fast processing time by searching the limited range of parameters for computing hough transform with a small range of ROI image. Moreover, the proposed algorithm removes bad candidates among the detected lines by selecting the two closest candidate lines from the position of user's input. After that, it accurately detects an interesting vertex without additionally required interactions by detecting an intersection point of the two lines. As a result, we believe that the proposed algorithm shows a 1.4 pixel distance error on average as a vertex detection accuracy under such conditions as a 5.7 pixel distance error on average as an inaccurate input.

Study on the Two-wavelength Digital Holography Using Double Fourier Transform (이중푸리에변환을 이용한 2 파장 디지털 홀로그래픽 연구)

  • Shin, Sang-Hoon;Jung, Won-Ki;Yu, Young-Hun
    • Korean Journal of Optics and Photonics
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    • v.21 no.3
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    • pp.91-96
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    • 2010
  • The size of a reconstructed image depends on the reconstruction distance and wavelength. The double fourier transform method is proposed to eliminate the dependence on the reconstruction distance and wavelength. We can get a fixed reconstructed image size by using the double fourier transform method. Two wavelength digital holography is proposed to measure the step height, which is larger than a single wavelength. The two image size of different wavelength holograms should be the same in order to apply two wavelength digital holography. We use two wavelength digital holography and double fourier transforms to measure the step height. The measured data were reasonable and we found that the double fourier transform is useful in two wavelength digital holography.

Design and Performance Analysis of Zoom-FFT Based FMCW Radar Level Meter (Zoom-FFT 기반 FMCW 레이더 레벨미터의 설계 및 성능분석)

  • Sanjeewa, Nuwan;Kim, Won-Ho
    • Journal of Satellite, Information and Communications
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    • v.9 no.2
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    • pp.38-44
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    • 2014
  • This paper presents design of a FMCW (Frequency Modulated Continuous Wave) level meter as well as simulation result of the designed system. The system is designed to measure maximum range of 20m since FMCW radar can be used for measuring short range distance. The distance is measured by analyzing the beat signal which is generated as result of mixing transmitting signal with the reflected received signal. The Fast Fourier Transform is applied to analyze the beat signal for calculating the displacement and Zoom FFT technique is used to minimize measurement error as well as increase the resolution of the measurement. The resolution of the measurement of the designed system in this paper is 2.2mm and bandwidth of 1.024GHz is used for simulation. Thus the simulation results are analyzed and compared in various conditions in order to get a comprehensive idea of frequency resolution and displacement resolution.

A Fast Semiautomatic Video Object Tracking Algorithm (고속의 세미오토매틱 비디오객체 추적 알고리즘)

  • Lee, Jong-Won;Kim, Jin-Sang;Cho, Won-Kyung
    • Proceedings of the KIEE Conference
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    • 2004.11c
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    • pp.291-294
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    • 2004
  • Semantic video object extraction is important for tracking meaningful objects in video and object-based video coding. We propose a fast semiautomatic video object extraction algorithm which combines a watershed segmentation schemes and chamfer distance transform. Initial object boundaries in the first frame are defined by a human before the tracking, and fast video object tracking can be achieved by tracking only motion-detected regions in a video frame. Experimental results shows that the boundaries of tracking video object arc close to real video object boundaries and the proposed algorithm is promising in terms of speed.

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Distance Relay Technique based on Variable Window Length using Least Square Error Method (최소자승법을 이용한 가변 윈도우 크기의 거리계전기법)

  • Jung, H.S.;Shin, M.C.;Lee, B.K.;Jang, S.I.;Choi, I.H.;Cho, P.H.
    • Proceedings of the KIEE Conference
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    • 2001.07a
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    • pp.226-228
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    • 2001
  • this paper presents the distance relay using wavelet transform and least square error method. Wavelet transform detect the faults in the high frequency region and remove the noises in the low frequency region. The variable window length LSE determine optimal window length to each fault case and estimate fault impedance very quickly.

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Marine Engine Wear Diagnosis and Assessment Using the Wavelet Transform (웨이블릿을 이용한 선박 엔진 마모 상태 진단 평가)

  • Kim, Kyung-Hwan;Jo, Jae-Han;Lee, Hyun;Lee, Jang-Myung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.6
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    • pp.845-850
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    • 2012
  • Currently power of the diesel engine is increasing continuously, where the wearing problems become more severe. The wearing happens irregularly inside the cylinder, which causes a high burden to the marine engine. In this paper, a novel scheme to measure the wearing and to represent the engine states has been proposed. To monitoring the states of the marine engine efficiently, a laser displacement sensor has been utilized to measure the wearing happening inside the marine engine. To eliminate the noise signals in the distance measurement, the wavelet transform has been adopted, which is robust against the noises caused by vibrations. An engine simulator is designed to develop the system for measuring the engine wears, where the superiority of the wavelet transform against the conventional filtering schemes has been demonstrated.

Human Iris Recognition using Wavelet Transform and Neural Network

  • Cho, Seong-Won;Kim, Jae-Min;Won, Jung-Woo
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.3 no.2
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    • pp.178-186
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    • 2003
  • Recently, many researchers have been interested in biometric systems such as fingerprint, handwriting, key-stroke patterns and human iris. From the viewpoint of reliability and robustness, iris recognition is the most attractive biometric system. Moreover, the iris recognition system is a comfortable biometric system, since the video image of an eye can be taken at a distance. In this paper, we discuss human iris recognition, which is based on accurate iris localization, robust feature extraction, and Neural Network classification. The iris region is accurately localized in the eye image using a multiresolution active snake model. For the feature representation, the localized iris image is decomposed using wavelet transform based on dyadic Haar wavelet. Experimental results show the usefulness of wavelet transform in comparison to conventional Gabor transform. In addition, we present a new method for setting initial weight vectors in competitive learning. The proposed initialization method yields better accuracy than the conventional method.

Time-Frequency Analysis of the Doppler Signals by Moving Targets (이동 표적에 의한 도플러 신호의 시간-주파수 분석)

  • Son, Joong-Tak;Lee, Seung-Houn;Park, Kil-Houm
    • Journal of the Korea Institute of Military Science and Technology
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    • v.8 no.2 s.21
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    • pp.38-48
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    • 2005
  • Instantaneous frequency of doppler signals is used to get the information of the relative velocity and the miss distance between a missile and a corresponding target. In this paper, we have performed time-frequency analysis and instantaneous frequency estimation with Short Time Fourier Transform(STFT), Wigner Ville Distribution(WVD) and Continuous Wavelet Transform(CWT) about the doppler signals generated by moving targets. Performance evaluation was performed using simulated doppler signals generated by a single moving target and two moving targets. From the results of the time-frequency analysis, we found that WVD method was the most efficient instantaneous frequency estimator among the three methods. But in case of two moving targets, WVD method got cross talks and CWT method got oscillation when two doppler frequencies were close to each other.

A Study on Intelligent Contents for Virtual University

  • Sik, Hong-You;Son, Jeong-Kwang;Park, Chong-Kug
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2004.04a
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    • pp.422-425
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    • 2004
  • Many believe that electronic distance teaming education transform higher education, saving money and improving learning qualify So, the open University, which teaches around 280,000 students at a distance, is examining the adaption of its distance teaching methods for the internet. But, there are only one type of distance learning education of one way direction. To understand all of a student which selected some of e teaming course, teacher must check that how many student to understand and what is the difficult problems. Without checking this condition, It will be a very difficult and boring distance learning course. In this paper, we introduce of intelligent learning contents of full duplex direction that teach understanding student and not understanding student. The computer simulation results confirms that full duplex e learning system has been proven to be much more efficient than one way direction which not considering about understanding problems.

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