• Title/Summary/Keyword: distance transform

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A Study on the Improved Line Detection Method for Pipeline Recognition of P&ID (P&ID의 파이프라인 인식 향상을 위한 라인 검출 개선에 관한 연구)

  • Oh, Sangjin;Chae, Myeonghoon;Lee, Hyun;Lee, Younghwan;Jeong, Eunkyung;Lee, Hyunsik
    • Plant Journal
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    • v.16 no.4
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    • pp.33-39
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    • 2020
  • For several decades, productivity in construction industry has been regressed and it is inevitable to improve productivity for major EPC players. One of challenges to achieve this goal is automatically extracting information from imaged drawings. Although computer vision technique has been advanced rapidly, it is still a problem to detect pipe lines in a drawing. Earlier works for line detection have problems that detected line elements be broken into small pieces and accuracy of detection is not enough for engineers. Thus, we adopted Contour and Hough Transform algorithm and reinforced these to improve detection results. First, Contour algorithm is used with Ramer Douglas Peucker algorithm(RDP). Weakness of contour algorithm is that some blank spaces are occasionally found in the middle of lines and RDP covers them around 17%. Second, HEC Hough Transform algorithm, we propose on this paper, is improved version of Hough Transform. It adopted iteration of Hough Transform and merged detected lines by conventional Hough Transform based on Euclidean Distance. As a result, performance of Our proposed method improved by 30% than previous.

Numerical Analysis on the Signal Characteristics for Scattered Far-field of Ultrasonic SH-Wave by the Internal Cavity (재료내 기공결함에 의한 SH형 초음파 원거리 산란장의 신호특성에 대한 수치해석)

  • Lee, Jun-Hyeon;Lee, Seo-Il;Park, Yun-Won
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.1 s.173
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    • pp.163-172
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    • 2000
  • In this study, the scattered far-field due to a cavity embedded in infinite media subjected to the incident SH-wave was calculated by the boundary element method. The effects of cavity shape and distance between internal cavity and internal point in infinite media were considered. The scattered far-field of the frequency domain was transformed into the signal of the time domain by using the Inverse Fast Fourier Transform(IFFT). It was found that the amplitude of scattered signal in time domain decreased with the increase of the distance between the detecting points of ultrasonic scattered field and the center of internal cavity in media. In addition, the time delay was clearly found in time domain waveform as the distance between the detecting points of ultrasonic scattered field and the center of internal cavity was gradually increased.

High-Speed Image Matching Method Using Geometry - Phase Information (기하 위상 정보를 이용한 고속 영상 정합 기법)

  • Chong Min-Yeong;Oh Jae-Yong;Lee Chil-Woo;Bae Ki-Tae
    • Journal of Korea Multimedia Society
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    • v.8 no.9
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    • pp.1195-1207
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    • 2005
  • In this paper, we describe image matching techniques which is automatically retrieving the exact matching area using geometry-phase information. We proposed a Matching Method which is rapidly estimating the correspondent points between adjacent images that included big-rotation and top-bottom movement element. It is a method that reduce computation quantity to be required to find an exact correspondent position using geometry-phase information of extracted points in images and DT map which set the distance value among feature points and other points on the basis of each feature point of a image. The proposed method shows good performance especially in the part to search a exact correspondent position between adjacent images that included big-rotation and top-bottom movement element.

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An Image Segmentation based on Chamfer Algorithm (Chamfer 알고리듬에 기초한 영상분리 기법)

  • Kim, Hak-Kyeong;Jeong, Nam-Soo;Lee, Myung-Suk;Kim, Sang-Bong
    • Proceedings of the KSME Conference
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    • 2001.06b
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    • pp.670-675
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    • 2001
  • This paper is to propose image segmentation method based on chamfer algorithm. First, we get original image from CCD camera and transform it into gray image. Second, we extract maximum gray value of background and reconstruct and eliminate the background using surface fitting method and bilinear interpolation. Third, we subtract the reconstructed background from gray image to remove noises in gray image. Fourth, we transform the subtracted image into binary image using Otsu's optimal thresholding method. Fifth, we use morphological filters such as areaopen, opening, filling filter etc. to remove noises and isolated points. Sixth, we use chamfer distance or Euclidean distance to this filtered image. Finally, we use watershed algorithm and count microorganisms in image by labeling. To prove the effectiveness, we apply the proposed algorithm to one of Ammonia-oxidizing bacteria, Acinetobacter sp. It is shown that both Euclidean algorithm and chamfer algorithm show over-segmentation. But Chamfer algorithm shows less over-segmentation than Euclidean algorithm.

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Thermomechanical interactions in transversely isotropic magneto thermoelastic solid with two temperatures and without energy dissipation

  • Lata, Parveen;Kaur, Iqbal
    • Steel and Composite Structures
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    • v.32 no.6
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    • pp.779-793
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    • 2019
  • The purpose of this research paper is to depict the thermomechanical interactions in transversely isotropic magneto thermoelastic solid with two temperatures and without energy dissipation in generalized LS theories of thermoelasticity. The Laplace and Fourier transform techniques have been used to find the solution of the problem. The displacement components, stress components, and conductive temperature distribution with the horizontal distance are computed in the transformed domain and further calculated in the physical domain numerically. The effect of two temperature and relaxation time are depicted graphically on the resulting quantities.

Effect of time harmonic sources on transversely isotropic thermoelastic thin circular plate

  • Lata, Parveen;Kaur, Iqbal
    • Geomechanics and Engineering
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    • v.19 no.1
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    • pp.29-36
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    • 2019
  • The present research deals with the deformation in transversely isotropic thin circular thermoelastic rotating plate due to time-harmonic sources. Frequency effect in the presence of rotation and two temperature is studied under thermally insulated as well as isothermal boundaries. The Hankel transform technique is used to find a solution to the problem. The displacement components, stress components, and conductive temperature distribution with the radial distance are computed in the transformed domain and further calculated in the physical domain using numerical inversion techniques. Some specific cases are also figured out from the current research.

A Study on an Open/Closed Eye Detection Algorithm for Drowsy Driver Detection (운전자 졸음 검출을 위한 눈 개폐 검출 알고리즘 연구)

  • Kim, TaeHyeong;Lim, Woong;Sim, Donggyu
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.7
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    • pp.67-77
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    • 2016
  • In this paper, we propose an algorithm for open/closed eye detection based on modified Hausdorff distance. The proposed algorithm consists of two parts, face detection and open/closed eye detection parts. To detect faces in an image, MCT (Modified Census Transform) is employed based on characteristics of the local structure which uses relative pixel values in the area with fixed size. Then, the coordinates of eyes are found and open/closed eyes are detected using MHD (Modified Hausdorff Distance) in the detected face region. Firstly, face detection process creates an MCT image in terms of various face images and extract criteria features by PCA(Principle Component Analysis) on offline. After extraction of criteria features, it detects a face region via the process which compares features newly extracted from the input face image and criteria features by using Euclidean distance. Afterward, the process finds out the coordinates of eyes and detects open/closed eye using template matching based on MHD in each eye region. In performance evaluation, the proposed algorithm achieved 94.04% accuracy in average for open/closed eye detection in terms of test video sequences of gray scale with 30FPS/$320{\times}180$ resolution.

Real Time W-band FMCW Distance Measuring Devices Using TMS320C6701 DSP (TMS320C6701 DSP를 이용한 실시간 W-대역 FMCW 거리측정장치)

  • Lee, Chang-Won
    • Journal of the Korea Institute of Military Science and Technology
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    • v.9 no.1 s.24
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    • pp.109-116
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    • 2006
  • This paper presents a real time distance measuring device using a W-band linear frequency modulated continuous wave(FMCW) radar and TMS320C6701 digital signal processor(DSP). We used FFT operation for measuring distance with the beat signals and the results of FFT could be converted to distance with ease. We presented how to implement a real time miniaturized hardware system including network protocols using a single DSP core. Also how to control the modulation signal of FMCW system to compensate the VCO nonlinearity using the Time Gating control of DSP is presented. We have shown that the proposed system has good performances for measuring distance in real time via outdoor environment experiments.

Selective Rendering of Specific Volume using a Distance Transform and Data Intermixing Method for Multiple Volumes (거리변환을 통한 특정 볼륨의 선택적 렌더링과 다중 볼륨을 위한 데이타 혼합방법)

  • Hong, Helen;Kim, Myoung-Hee
    • Journal of KIISE:Computer Systems and Theory
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    • v.27 no.7
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    • pp.629-638
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    • 2000
  • The main difference between mono-volume rendering and multi-volume rendering is data intermixing. In this paper, we first propose a selective rendering method for fast visualizing specific volume according to the surface level and then present data intermixing method for multiple volumes. The selective rendering method is to generate distance transformed volume using a distance transform to determine the minimum distance to the nearest interesting part and then render it. The data intermixing method for multiple volumes is to combine several volumes using intensity weighted intermixing method, opacity weighted intermixing method, opacity weighted intermixing method with depth information and then render it. We show the results of selective rendering of left ventricle and right ventricle generated from EBCT cardiac images and of data intermixing for combining original volume and left ventricular volume or right ventricular volume. Our method offers a visualization technique of specific volume according to the surface level and an acceleration technique using a distance transformed volume and the effective visual output and relation of multiple images using three different intermixing methods in three-dimensional space.

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Road Lane and Vehicle Distance Recognition using Real-time Analysis of Camera Images (카메라 영상의 실시간 분석에 의한 차선 및 차간 인식)

  • Kang, Moon-Seol;Kim, Yu-Sin
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.12
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    • pp.2665-2674
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    • 2012
  • This paper propose the method to recognize the lanes and distance between cars in real-time which detects dangerous situations and helps safe driving in the actual road environment. First of all, it extracts the area of interest corresponding to roads and cars from the road image photographed by using the forward-looking camera. Through the hough transform for the area of interest, this study detects linear components and also selects the lane and conducts filtering by calculating probability. And through the shadow threshold analysis of the cars in front within the area of interest, it extracts the objects of cars in front and calculates the distance from cars in front. According to the result of applying the suggested technology to recognize the lane and distance between cars to the road situation for testing, it showed over 95% recognition rate; thus, it has been proved that it can respond to safe driving.