• Title/Summary/Keyword: difference edge

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Improvement of Building Region Correspondence between SLI and Vector Map Based on Region Splitting (영역분할에 의한 SLI와 벡터 지도 간의 건물영역 일치도 향상)

  • Lee, Jeong Ho;Ga, Chill O;Kim, Yong Il;Yu, Ki Yun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.30 no.4
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    • pp.405-412
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    • 2012
  • After the spatial discrepancy between SLI(Street-Level Imagery) and vector map is removed by their conflation, the corresponding building regions can be found based on SLI parameters. The building region correspondence, however, is not perfect even after the conflation. This paper aims to improve the correspondence of building regions by region splitting of an SLI. Regions are initialized by the seed lines, projection of building objects onto SLI scene. First, sky images are generated by filtering, segmentation, and sky region detection. Candidates for split lines are detected by edge detector, and then images are splitted into building regions by optimal split lines based on color difference and sky existence. The experiments demonstrated that the proposed region splitting method had improved the accuracy of building region correspondence from 83.3% to 89.7%. The result can be utilized effectively for enhancement of SLI services.

A Study on the Residual Stress of AISI 4140 Formed during Surface Hardening Treatment by using the CO2 Laser Beam (CO2레이저 비임을 이용한 표면경화 처리중 형성된 AISI 4140의 잔류응력에 관한 연구)

  • Park, K.W.;Lee, J.B.;Han, Y.H.;Lee, S.Y.
    • Journal of the Korean Society for Heat Treatment
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    • v.9 no.4
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    • pp.289-299
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    • 1996
  • This study has been performed to investigate into some effects of power density and traverse speed of laser beam on the microstructure, hardness and residual stress of AISI 4140 treated by laser surface hardening technique. Optical micrograph has shown that large martensite and a small amount of retained austenite in outermost surface layer and fine lath martensite in inner surface hardened layer are formed under the condition of a given power density and traverse speed. Hardness measurements have revealed that as the power density increases at a given 2.0m/min of the traverse speed, the maximum hardness values of outermost surface hardened layer is increased from Hv=635 to Hv=670. X-ray analysis for residual stress has exhibited that low compressive residual stress values are obtained in center point of the cress section of surface hardened layer with in mid point between the edge and the center point, about 1.5mm from the center point, due simply to a difference in self-quenching rate. It has been shown that the higher the power density at a given traverse speed and the olwer the traverse speed at a given power density, the more the compressive residual stress values are increased due to an increase in the input heat of laser beam.

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Recognition of Car License Plate Using Geometric Information from Portable Device Image (휴대단말기 영상에서의 기하학적 정보를 이용한 차량 번호판 인식)

  • Yeom, Hee-Jung;Eun, Sung-Jong;WhangBo, Taeg-Keun
    • The Journal of the Korea Contents Association
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    • v.10 no.10
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    • pp.1-8
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    • 2010
  • Recently, the character image processing technology using portable device camera image at home and abroad are actively conducted, but Practical use are lower rate because of accuracy and time-consuming process problems. In this paper, we propose the license plate recognition method based on geometric information from portable device camera image. In the extracted license plate region we recognize characters using the chain code and the Thickness information through the cumulative projected edge after performing the pre-processing work considering the angle difference, the contrast enhancement and the low resolution from portable device camera image. The proposed algorithm is effective and accurate recognition by light and reducing the processing time. And, the results from the character recognition success rate was 95%. In the future, we will research about license plate recognition algorithm using long distance image or added motion blur image.

Robust Digital Watermarking to JPEG Compression (JPEG 압축에 견고한 디지털 워터마킹)

  • 이혜주;박지환
    • Journal of Korea Multimedia Society
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    • v.3 no.1
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    • pp.53-62
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    • 2000
  • Digital watermarking has been considered as an important technique to protect the copyright of digital content. It is essential that a watermark embedded in a still or moving image resists against various attacks ranging from compression, filtering to cropping. In particular, as JPEG is a dominant still image compression standard for Internet applications, digital watermarking methods that are robust against the JPEG compression are especially required. Most digital watermarking methods proposed so far work by modulating pixels/coefficients without considering the quality level of JPEG, which renders watermarks readily removable. In this paper, we proposed a new digital watermarking method as follows. For providing the robustness against JPEG, the quality level of JPEG is used as parameter on watermarking so as to compute the loss of image caused by JPEG compression and we compute the difference of an original image resulted from JPEG compression. Also in proposed method, we compute the visual components that are derived from the information of edge within image and consideration of brightness discrimination which is one of human visual system's properties. Thus, we proposed new watermarking scheme that after constructing a watermark by considering the loss of image resulted from JPEG compression and visual components derived from the human visual system, the watermark is embedded into the image.

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Analysis of Color Constancy Methods for Recovering Skin Color Independent of Illuminants (광원에 독립적인 피부색 복원을 위한 색 항등성 기법 분석)

  • Lee, Woo-Ram;Hwang, Dong-Guk;Jun, Byoung-Min
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.10C
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    • pp.621-628
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    • 2011
  • The skin color has been used as important cues in the systems for detecting or recognizmg the face. However, the color difference in images under different illuminants makes it difficult to find out the skin in these systems. For solving the problem, this paper proposes a method of recovering skin colors based on well-known color constancy approaches, such as Retinex, Gray World, White Patch, and Simplified Horn. To acquire experimental images under the colored scene illumination, the effects of colored illuminants were added to source images. Next, result images, having the corrected skin color by the constancy methods, were derived from the source images. The experiment results showed that most of the skin colors in our experiments were recovered into some steady range in the color space, and that Gray World had higher performance than the other methods compared.

Image Analysis for Discrimination of Neoplastic Cellis in Spatial Frequency Domain (종양세포식별을 위한 공간주파수영역에서의 화상해석)

  • 나철훈;김창원;김현재
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.3
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    • pp.385-396
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    • 1993
  • In this paper, a improved method of digital image analysis required in basic medical science for diagnosis of cells was proposed. The object image was the thyroid gland cell image, and the purpose was automatic discrimination of three classes cells(normal cell, follicular neoplastic cells, and papillary neoplastic cells) by difference of chromatin patterns. To segment the cell nucleus from background, the region segmentation algorithm by edge tracing was proposed. And feature parameter was obtained from discrete Fourier transformation of image. After construct a feature sample group of each cells, experiment of discrimination was executed with any verification cells. As a consequency of using features proposed in this paper, get a better recognition rate(70-90%) than previously reported papers, and this method give shape to get objectivity and fixed quantity in diagnosis of cells, The methods described in this paper be used immediately for discrimination of neoplastic cells.

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The Effects of Thoracic Spine Thrust Manipulation on Shoulder Pain, Range of Motion and Muscle Activity in 30′s Adults with Rounded Shoulder Posture (흉추 도수교정이 둥근어깨자세를 가진 30대 성인남녀의 통증, 관절가동범위, 근활성도에 미치는 영향)

  • Lee, Jae-nam;Yang, Seong-hwa;Gong, Won-tae
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.22 no.1
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    • pp.17-25
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    • 2016
  • Purpose: This study was aimed to determine the effects of thoracic spine thrust manipulation on muscle activities of the scapular upward rotators and middle deltoid, active range of motion (AROM), shoulder pain, and rounded shoulder posture in young adults with rounded shoulder. Methods: The subjects were 30 young adults (14 males, 16 females) with rounded shoulder. Thirty subjects were randomly assigned to an experimental (manipulation) and control (placebo) groups of fifteen subjects respectively. The manipulation group received the manipulation (high velocity, low amplitude), which was performed by a physical therapist with the subject in the supine position and with the arms crossed over the chest and hands passed over the shoulders. For the sham group, the same procedure was performed, with the exception that the high-velocity thrust was not applied. Measurements were taken before and after the intervention. Muscle activity of upper and lower trapezius, serratus anterior, middle deltoid was measured using surface electromyography. Visual analog scale (VAS) was used for shoulder pain. Goniometry was used for shoulder abduction active range of motion (AROM). Straight edge was used for supine rounded shoulder posture (RSP) distance. Results: The muscle activity of the upper trapezius, lower trapezius and middle deltoid muscle increased significantly after the intervention (p<.05). However, no significant difference was observed in serratus anterior muscle (p>.05). The VAS was significantly decreased and AROM significantly increased after the intervention (p<.05). The distance of RSP were not significant (p>.05). The control group showed no differences before and after the intervention (p>.05). Conclusion: The results of this study suggest that thoracic spine thrust manipulation can be an effective component of treatment plan to improve pain and function.

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A Slotted Square-Patch Type Balun-BPF (슬롯을 가진 사각 패치형의 발룬-대역 통과 여파기)

  • Oh, Song-Yi;Hwang, Hee-Yong
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.21 no.11
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    • pp.1208-1213
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    • 2010
  • In this paper, a microstrip balun-BPF of slotted-square-patch type is proposed. The conventional balun-BPF has some drawbacks of narrow bandwidth and high insertion loss. In order to improve these weak points, we used a square patch in designing balun-BPF on which two slots intersecting perpendicularly and one corner-edge perturbation are adopted. This structure allows one of the most effective use of the patch space so that the insertion loss can be decreased. Changing the slot lengths is use to control the operating frequency and the bandwidth of the balun-BPF. A fabricated balun-BPF shows wide bandwidth of 300 MHz(12.7 %), small insertion loss of 0.56 dB, phase difference of $184^{\circ}{\pm}15^{\circ}$ and amplitude imbalances of within 1 dB between two output ports at 2.4 GHz band.

Analysis of Particle Deposition onto a Heated or Cooled, Horizontal Free-Standing Wafer Surface (가열 또는 냉각되는 수평웨이퍼 표면으로의 입자침착에 관한 해석)

  • 유경훈;오명도;명현국
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.5
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    • pp.1319-1332
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    • 1995
  • Numerical analysis was performed to characterize the particle deposition behavior on a horizontal free-standing wafer with thermophoretic effect under the turbulent flow field. A low Reynolds number k-.epsilon. turbulence model was used to analyze the turbulent flow field around the wafer, and the temperature field for the calculation of the thermophoretic effect was predicted from the energy equation introducing the eddy diffusivity concept. The deposition mechanisms considered were convection, diffusion, sedimentation, turbulence and thermophoresis. For both the upper and lower surfaces of the wafer, the averaged particle deposition velocities and their radial distributions were calculated and compared with the laminar flow results and available experimental data. It was shown by the calculated averaged particle deposition velocities on the upper surface of the wafer that the deposition-free zone, where the deposition velocite is lower than 10$^{-5}$ cm/s, exists between 0.096 .mu.m and 1.6 .mu.m through the influence of thermophoresis with positive temperature difference of 10 K between the wafer and the ambient air. As for the calsulated local deposition velocities, for small particle sizes d$_{p}$<0.05 .mu.m, the deposition velocity is higher at the center of the wafer than at the wafer edge, whereas for particle size of d$_{p}$ = 2.0 .mu.m the deposition takes place mainly on the inside area of the wafer. Finally, an approximate model for calculating the deposition velocities was recommended and the calculated deposition velocity results were compared with the present numerical solutions, those of Schmidt et al.'s model and the experimental data of Opiolka et al.. It is shown by the comparison that the results of the recommended model agree better with the numerical solutions and Opiolka et al.'s data than those of Schmidt's simple model.

Numerical Analysis of Natural Convection from an Inclined Ice Flat Plate Immersed in cold Water Near Its Density Maximum (최대밀도점 부근의 물속에 잠겨있는 경사진 얼음평판에 의한 자연대류의 수치해석)

  • 유갑종;추홍록
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.11
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    • pp.2136-2149
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    • 1992
  • The natural convection from an inclined ice flat plate immersed in cold water near its density maximum is studied numerically. Finite difference analysis has been performed for the heat and momentum transfer with respect to various inclined angles and ambient water temperatures. The results of the analysis are presented for ambient water temperatures, 1.0deg. C. leq. T/sub .inf./.leq. 15.0deg. C and the inclined anales from 0deg to 60deg. They include velocity profiles, temperature profiles, melting velocities, and mean Nusselt numbers for entire flow fields, Generally, in the range of 0deg. C .leq.theta. .leq. 60.deg. C, the results show three distinct flow regimes, In the range of 1.0 deg. C .leq. T/sub .inf./ .leq. 4.6 .deg. C, the greatest mean Nuselt number exists about 3.0deg. C. In the range of 5.7deg. C .leq. T/sub .inf./ .leq. 15.0deg. C, mean Nuselt number increases as ambient water temperature increases. Also, the mean Nuselt number decreases as the inclined angle increases. This theoretical results are compared with previous experimental ones and multiple steady state ones.