• Title/Summary/Keyword: lines detection

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An Algorithm for detection and Resolution of Train Conflicts Occurring Within Station (역내 열차 경합 검지 및 해소를 위한 수리 모형 및 해법)

  • Park, Bum-Hwan;Kim, Kyung-Min;Hong, Soon-Heum;Kim, Young-Hoon
    • Journal of the Korean Society for Railway
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    • v.10 no.2 s.39
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    • pp.179-185
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    • 2007
  • In large station with high density traffic, trains can be hardly controlled by CTC but by station dispatcher because CTC has difficulties in monitoring all states of affairs happening within each station such as departures, arrivals of many trains from different lines and shunting of trains to move between yards and platforms, etc. Therefore the station's dispatcher has to make quick decision about how to reschedule the times and routes for all the trains scheduled within a specific time window. And such decision becomes harder when an unexpected delay occurs because a delay occurring in a train propagates other trains as time goes on. Generally, it is called the conflict detection and resolution to adjust beforehand the distorted schedule due to a delay to original schedule. Our research is different from the state of the arts in that ours determines simultaneously the routes and the times of arrival and departure of trains, although others do only the arrival and departure time of the trains without considering the alternative routes and shunting of the station. This study suggests a mathematical approach for how to detect in advance and resolve efficiently the conflicts occurring within a station and it will be shown how to reduce delay using our approach by means of analysing the schedule of ChyungRyangRi station.

A Study on the Defection of Arcing Faults in Transmission Lines and Development of Fault Distance Estimation Software using MATLAB (MATLAB을 이용한 송전선로의 아크사고 검출 및 고장거리 추정 소프트웨어 개발에 관한 연구)

  • Kim, Byeong-Cheon;Park, Nam-Ok;Kim, Dong-Su;Kim, Gil-Hwan
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.51 no.4
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    • pp.163-168
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    • 2002
  • This paper present a new verb efficient numerical algorithm for arcing faults detection and fault distance estimation in transmission line. It is based on the fundamental differential equations describing the transients on a transmission line before, during and alter the fault occurrence, and on the application of the "Least Error Squares Technique"for the unknown model parameter estimation. If the arc voltage estimated is a near zero, the fault is without arc, in other words the fault is permanent fault. If the arc voltage estimated has any high value, the faust is identified as an fault, or the transient fault. In permanent faults case, fault distance estimation is necessary. This paper uses the model of the arcing fault in transmission line using ZnO arrestor and resistance to be implemented within EMTP. One purpose of this study is to build a structure for modeling of arcing fault detection and fault distance estimation algorithm using Matlab programming. In this paper, This algorithm has been designed in Graphic user interface(GUI).

Real-time Vanishing Point Detection Using Histogram of Oriented Gradient (Histogram of Oriented Gradient를 이용한 실시간 소실점 검출)

  • Choi, Ji-Won;Kim, Chang-Ick
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.48 no.2
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    • pp.96-101
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    • 2011
  • Vanishing point can be defined as a point generated by converged perspective lines, which are parallel in the real world. In this paper, we propose a real-time vanishing point detection algorithm using this fundamental feature of vanishing point. The existing methods 1) require high computational cost or 2) are restricted to specific image contents. The proposed method detects the vanishing point in images based on the block-wise HOG (Histogram of Oriented Gradient) descriptor. First, we compute the HOG descriptor in a block-wise manner, then estimate the location of the vanishing point using the proposed dynamic programing. Experiments are performed on diverse images to confirm the efficiency of the proposed method.

Simultaneous Observations of SiO and $H_2O$ Masers toward Symbiotic Stars

  • Cho, Se-Hyung;Kim, Jae-Heon
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.2
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    • pp.79.2-79.2
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    • 2010
  • We present the results of simultaneous observations of SiO v=1, 2, J=1-0, $^{29}SiO$ v=0, J=1-0, and $H_2O$ $6_{16}-5_{23}$ maser lines performed with the KVN Yonsei 21 m radio telescope from 2009 Nov. to 2010 Jan (ApJ, 719, 126, 2010). We searched for these masers in 47 symbiotic stars and detected maser emission from 21 stars, giving the first time detection from 19 stars. Both SiO and $H_2O$ masers were detected from seven stars of which six stars are D-type symbiotic and one is an S-type star, WRAY 15-1470. In the SiO maser emission, the $^{28}SiO$ v=1 maser was detected from 10 stars, while the v=2 maser detected from 15 stars. In particular, the $^{28}SiO$ v=2 maser emission without the v=1 maser detection was detected from nine stars with its detection rate of 60 %, which is much higher than that of isolated Miras/red giants. The $^{29}SiO$ v=0 maser emission was also detected from two stars, H 2-38 and BF Cyg, together with the $^{28}SiO$ v=2 maser. We conclude that these different observational results between isolated Miras/red giants and symbiotic stars may be related with the presence of hot companions in a symbiotic binary system.

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Caption Detection and Recognition for Video Image Information Retrieval (비디오 영상 정보 검색을 위한 문자 추출 및 인식)

  • 구건서
    • Journal of the Korea Computer Industry Society
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    • v.3 no.7
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    • pp.901-914
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    • 2002
  • In this paper, We propose an efficient automatic caption detection and location method, caption recognition using FE-MCBP(Feature Extraction based Multichained BackPropagation) neural network for content based retrieval of video. Frames are selected at fixed time interval from video and key frames are selected by gray scale histogram method. for each key frames, segmentation is performed and caption lines are detected using line scan method. lastly each characters are separated. This research improves speed and efficiency by color segmentation using local maximum analysis method before line scanning. Caption detection is a first stage of multimedia database organization and detected captions are used as input of text recognition system. Recognized captions can be searched by content based retrieval method.

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Development of HIF Detection Rules for Distribution Line (배전선로 보호를 위한 고저항 사고 검출 룰의 개발)

  • Kim, K.H.;Chang, S.I.;Choi, S.K.;Choi, J.H.;Hwang, E.C.;Kim, N.H.;Kang, Y.C.;Park, J.K.;Kim, I.D.
    • Proceedings of the KIEE Conference
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    • 1997.07c
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    • pp.1006-1008
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    • 1997
  • This paper presents the logic based High Impedance Fault(HIF) detection rules for distribution lines. Due to the characteristics of HIF, which shows low current on relaying points, it is difficult to detect the fault occurred in distribution line by the conventional overcurrent relay(OCR) and/or harmonics relay. The HIF data were generated by using TACS in EMTP. In this paper, The harmonic index is defined as the ratio of harmonic component to fundamental component. The proposed HIF detection rules are obtained by analysing the difference between normal condition and HIF condition.

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Skew Detection for Thai Printed Document Images

  • Premchaiswad, Wichian;Duangphasuk, Surakarn
    • Proceedings of the IEEK Conference
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    • 2000.07a
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    • pp.326-328
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    • 2000
  • The paper proposes the scheme of skew detection for Thai printed document images by using linear regression algorithm. It intends to use with the Thai character recognition systems to reduce the skew detection time. This scheme begins by finding the center of gravity of a document image. This point is used as the starting point for gathering data in the scheme. The data is obtained by scanning incrementally one pixel in vertically with the width of 20-pixels. After the scanning process, if data Is different from it's neighbor more than ${\pm}$ 15 pixels, it will be considered as noise or data in other lines and will be deleted. The last step is the operation by using linear regression algorithm on these selected data and the skew angle will be obtained. The proposed method has been tested with 45 document images with different fonts, sizes and skew angles. The experiment results show that the proposed method can detect the skew angle with the error of less then one degree. The average processing time is about 19 times faster than that of the Hough Transform method.

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Precise Detection of Coplanar Checkerboard Corner Points for Stereo Camera Calibration Using a Single Frame (스테레오 카메라 캘리브레이션을 위한 동일평면 체커보드 코너점 정밀검출)

  • Park, Jeong-Min;Lee, Jong-In;Cho, Joon-Bum;Lee, Joon-Woong
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.7
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    • pp.602-608
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    • 2015
  • This paper proposes an algorithm for precise detection of corner points on a coplanar checkerboard in order to perform stereo camera calibration using a single frame. Considering the conditions of automobile production lines where a stereo camera is attached to the windshield of a vehicle, this research focuses on a coplanar calibration methodology. To obtain the accurate values of the stereo camera parameters using the calibration methodology, precise localization of a large number of feature points on a calibration target image should be ensured. To realize this demand, the idea with respect to a checkerboard pattern design and the use of a Homography matrix are provided. The calibration result obtained by the proposed method is also verified by comparing the depth information from stereo matching and a laser scanner.

A Study on the Fault Detection and Discrimination of Transmission Line using Fault-generated High Frequency Signals (고주파를 이용한 송전선로의 사고 검출 및 판별에 관한 연구)

  • Lee, Dong-Jun;Kim, Chul-Hwan;Kim, Il-Dong
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.8
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    • pp.924-931
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    • 1999
  • Most conventional protection relays are based on processing information in the spectrum that is close to or at power frequency. It is, however, widely known that faults on transmission lines produce frequency components of a wide range. High frequency signals caused by sudden changes in system voltage that occurs in the immediate post-fault period are generally outside the bandwidth of receptibility of most protection scheme. In this respect, a specially designed stack tuner is connected to the coupling capacitor of CVT, in order to capture the high frequency signals. Digital signal processing is then applied to the captured information to determine whether the fault is inside or outside the protected zone, and to discriminate the fault type. In this paper, modal transform is not applied to fault generated signals, because signals which are converted by modal transform are not have an information of each phase any longer. Instead, using peak voltage value of data windows is able to discriminate fault type. The paper concludes by presenting fault detection and discrimination of various faults on transmission line which are based on extensive simulation studies carried out on a typical 154kV Korean transmission line, using the EMTP software.

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Quality Test and Control of Kinematic DGPS Survey Results

  • Lim, Sam-Sung
    • Journal of Korean Society for Geospatial Information Science
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    • v.10 no.5 s.23
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    • pp.75-80
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    • 2002
  • Depending upon geographical features and surrounding errors in the survey field, inaccurate positioning is inevitable in a kinematic DGPs survey. Therefore, a data inaccuracy detection algorithm and an interpolation algorithm are essential to meet the requirement of a digital map. In this study, GPS characteristics are taken into account to develop the data inaccuracy detection algorithm. Then, the data interpolation algothim is obtained, based on the feature type of the survey. A digital map for 20km of a rural highway is produced by the kinematic DGPS survey and the features of interests are lines associated with the road. Since the vertical variation of GPS data is relatively higher, the trimmed mean of vertical variation is used as criteria of the inaccuracy detection. Four cases of 0.5%, 1%, 2.5% and 5% trimmings have been experimented. Criteria of four cases are 69cm, 65cm, 61cm and 42cm, respectively. For the feature of a curved line, cublic spine interpolation is used to correct the inaccurate data. When the feature is more or less a straight line, the interpolation has been done by a linear polynomial. Difference between the actual distance and the interpolated distance are few centimeters in RMS.

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