• Title/Summary/Keyword: Scanline

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Accelerating Scanline Block Gibbs Sampling Method using GPU (GPU 를 활용한 스캔라인 블록 Gibbs 샘플링 기법의 가속)

  • Zeng, Dongmeng;Kim, Wonsik;Yang, Yong;Park, In Kyu
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2014.06a
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    • pp.77-78
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    • 2014
  • A new MCMC method for optimization is presented in this paper, which is called the scanline block Gibbs sampler. Due to its slow convergence speed, traditional Markov chain Monte Carlo (MCMC) is not widely used. In contrast to the conventional MCMC method, it is more convenient to parallelize the scanline block Gibbs sampler. Since The main part of the scanline block Gibbs sampler is to calculate message between each edge, in order to accelerate the calculation of messages passing in scanline sampler, it is parallelized in GPU. It is proved that the implementation on GPU is faster than on CPU based on the experiments on the OpenGM2 benchmark.

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Estimation of Micro-discontinuity Distribution Using Scanline Survey in Granites (조사선을 이용한 화강암의 미세 불연속면 분포성상 평가)

  • 이상은;조상호;양형식;박홍민
    • Tunnel and Underground Space
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    • v.9 no.4
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    • pp.364-372
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    • 1999
  • In this paper, mechanical characteristics of micro-defects in granitic rock was studied. Crack spacing and length were investigated by scanline survey in specimen of granite. To estimate the direction and distribution of potential microcrack in granite, thin sections were made for three direction of Rift, Grain and Hardway axis of the rock specimen. The density and length of microcrack were investigated quantitatively. Three directions of microcracks are comparatively perpendicular. Crack density varies as direction differs, but crack length doesn't show influence of direction.

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Sampling Bias of Discontinuity Orientation Measurements for Rock Slope Design in Linear Sampling Technique : A Case Study of Rock Slopes in Western North Carolina (선형 측정 기법에 의해 발생하는 불연속면 방향성의 왜곡 : 서부 North Carolina의 암반 사면에서의 예)

  • 박혁진
    • Journal of the Korean Geotechnical Society
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    • v.16 no.1
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    • pp.145-155
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    • 2000
  • Orientation data of discontinuities are of paramount importance for rock slope stability studies because they control the possibility of unstable conditions or excessive deformation. Most orientation data are collected by using linear sampling techniques, such as borehole fracture mapping and the detailed scanline method (outcrop mapping). However, these data, acquired by the above linear sampling techniques, are subjected to bias, owing to the orientation of the sampling line. Even though a weighting factor is applied to orientation data in order to reduce this bias, the bias will not be significantly reduced when certain sampling orientations are involved. That is, if the linear sampling orientation nearly parallels the discontinuity orientation, most discontinuities orientation data which are parallel to sampling line will be excluded from the survey result. This phenomenon can cause serious misinterpretation of discontinuity orientation data because critical information is omitted. In the case study, orientation data collected by using the borehole fracture mapping method (vertical scanline) were compared to those based on orientation data from the detailed scanline method (horizontal scanline). Differences in results for the two procedures revealed a concern that a representative orientation of discontinuities was not accomplished. Equal-area, polar stereo nets were used to determine the distribution of dip angles and to compare the data distribution fur the borehole method versus those for the scanline method.

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Scanline Based Metric for Evaluating the Accuracy of Automatic Fracture Survey Methods (자동 균열 조사기법의 정확도 평가를 위한 조사선 기반의 지표 제안)

  • Kim, Jineon;Song, Jae-Joon
    • Tunnel and Underground Space
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    • v.29 no.4
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    • pp.230-242
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    • 2019
  • While various automatic rock fracture survey methods have been researched, the evaluation of the accuracy of these methods raises issues due to the absence of a metric which fully expresses the similarity between automatic and manual fracture maps. Therefore, this paper proposes a geometry similarity metric which is especially designed to determine the overall similarity of fracture maps and to evaluate the accuracy of rock fracture survey methods by a single number. The proposed metric, Scanline Intersection Similarity (SIS), is derived by conducting a large number of scanline surveys upon two fracture maps using Python code. By comparing the frequency of intersections over a large number of scanlines, SIS is able to express the overall similarity between two fracture maps. The proposed metric was compared with Intersection Over Union (IoU) which is a widely used evaluation metric in computer vision. Results showed that IoU is inappropriate for evaluating the geometry similarity of fracture maps because it is overly sensitive to minor geometry differences of thin elongated objects. The proposed metric, on the other hand, reflected macro-geometry differences rather than micro-geometry differences, showing good agreement with human perception. The metric was further applied to evaluate the accuracy of a deep learning-based automatic fracture surveying method which resulted as 0.674 (SIS). However, the proposed metric is currently limited to 2D fracture maps and requires comparison with rock joint parameters such as RQD.

Design and Simulation of Edge Painting Machine for Image Rasterization (Image rasterization을 위한 Edge Painting Machine의 설계 및 simulation)

  • Choi, Sang-Gil;Kim, Sung-Soo;Eo, Kil-Su;Kyung, Chong-Min
    • Proceedings of the KIEE Conference
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    • 1987.07b
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    • pp.1492-1494
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    • 1987
  • This paper describes a hardware architecture called Edge Painting Machine for real time generation of scan line images for raster scan graphics display. The Edge Painting Machine consists of Scanline Processor which converts polygon data sorted in their depth priority into a set of scan line commands for each scan line, and Edge Painting Tree which converts the scanline commands set into a raster line image. Edge painting tree has been designed using combinational logic circuit. The designed circuit has been simulated to verify the proper functioning. A salient feature of the EPT is that hardware composition is simple, because each processor is constituted by only combinational logic circuit.

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A Stereo Matching by the Iterative Relaxation Using the Consensus of Matching Possibility (정합 일치성을 이용한 반복 이완 스테레오 정합)

  • 이왕국;김용석;도경훈;하영호
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.1
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    • pp.39-49
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    • 1995
  • Stereo vision is useful to obtain three dimensional depth information from two images taken from different view points. In this paper, we reduce searching area for correspondence by using the intra-scanline constraint, and utilize the inter-scanline constraint and the property of disparity continuity among the neighboring pixels for relaxation. Nodes with 3-D stucture are located on the axes of two views, and have matching possibility of correspondent pixels of two images. A matching is accepted if a node at the intersection of the disparity axes has the greatest matching possibility. Otherwise, the matching possibility of the node is updated by relaxation with the cooperation of neighboring nodes. Further relaxation with competition of two views is applied to a matching possibility of randomly selected node. The consensus of two views increases the confidence of matching, and removes a blurring phenomenon on the discontinuity of object. This approach has been tested with various types of image such as random dot stereogram and aerial image, and the experimental results show good matching performance.

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Stereo matching using the divide-and-conquer method in the disparity space image (시차 공간에서 divide-and-conquer 방법을 이용한 스테레오 정합)

  • 이종민;김대현;윤용인;최종수
    • Proceedings of the IEEK Conference
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    • 2003.11a
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    • pp.179-182
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    • 2003
  • This paper proposes a new stereo matching algorithm using both the divide-and-conquer method and the DSI(Disparity Space Image) technique. Firstly, we find salient feature points on the each scanline of the left image and find the corresponding feature point at the right image. Then the problem of a scanline is divided into several subproblems. By this way, matching of the subintervals is implemented by using the DSI technique. The DSI technique for stereo matching process is a very efficient solution to find matches and occlusions simultaneously and it is very speedy. In addition, we apply three occluding patterns to process occluded regions, as a result, we reduce mismatches at the disparity discontinuity.

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Research on the Production Method of Three-Dimensional Image Scanimation (3D 입체 이미지 스케니메이션 제작 기법 연구)

  • Shan, Xinyi;Chung, Jean-Hun
    • Journal of Digital Convergence
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    • v.14 no.12
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    • pp.209-215
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    • 2016
  • The quantity of image frames, the widths of transparent slits, and the black bars on the scanline are the three basic elements of scanimation. Besides, the size of scanimation, the color and contrast of scanimation, and the brightness of scanline, etc, can also influence the optical illusion of scanimation. Based on the recent principle of production of 2D scanimation, and through asking questions, and making corresponding experiment, this research finally gets to the conclusion. Based on the principle of production of 3D scanimation, and through various basic testing, this paper aims to verify how to bring out the best visual effects (optical illusion) of animated illusion scanimation in publications by using the 3D animation in the publications. And the future goal is to study and flexibly use Z-axis space in the scanimation.

Comparative Study of Square-Inventory Method with Scanline Survey in Slope Stability Analysis (사면 안정 분석을 위한 정면적법과 선조사법의 비교연구)

  • Cheong, Sang-Won;Choi, Byoung-Ryol
    • The Journal of Engineering Geology
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    • v.19 no.2
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    • pp.119-129
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    • 2009
  • In relation to slope stability analysis, geologic characteristics and engineering properties of the discontinuities in three slopes selected are compared and analyzed by both square-inventory method and scanline survey. The aim of the study is in evaluating which method is applied better in slope stability analysis by comparing results of the two methods with those of direct observation on outcrop of slope failures generated. In each slope, results of comparative analysis among geologic and engineering properties are analyzed similarly one another. However, results of orientation analysis in slope 2 are different each other, which indicates orientation of joints in slope 2 depends on persistency and frequency of each joint and also indicates appearance of new joint set with different orientation. Probability density distribution and spacing in slope 3 are high in comparison to those in slope 2 and 3. The reasons are that distribution of psammitic rocks and development of minor folds in slope 3 unlike slope 2 and 3 are closely associated with development of joints. The research data indicate that the square-inventory method predicts more precise failure aspects and is more effective way than scanline survey in analyzing slope stability of the study area.

A study of the Sampling Bias Correction on Joint Data from 1D Survey Line (1D 측선에 의한 절리 자료에 대한 편향 보정 기법에 관한 연구)

  • 엄정기
    • Tunnel and Underground Space
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    • v.13 no.5
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    • pp.344-352
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    • 2003
  • The procedures to correct sampling biases for discontinuity data obtained from 1D survey line(borehole or scanline) is addressed. The Probability of intersection between the survey line and a circular discontinuity is considered, and a correction far orientation bias is developed assuming discontinuities as equivalent circular disks. The correction incorporates the effect of the angle between the direction of survey line and each discontinuity plane belonging to the discontinuity cluster, size of each discontinuity and length of the survey line. A procedure is provided to estimate unbiased discontinuity spacing parameters using the discontinuity spacing data based on the measurements carried out on a finite length of the survey line.