• Title/Summary/Keyword: Straight edge

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Correction of Syndactyly using Pentagonal Flap with Minimal Skin Graft (오각형피판과 최소한의 피부이식을 이용한 합지증의 교정)

  • Bae, Byoung Man;Eo, Su Rak;Kim, In Kyu;Koh, Sung Hoon;Jones, Neil F.
    • Archives of Plastic Surgery
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    • v.34 no.1
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    • pp.64-69
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    • 2007
  • Purpose: The key of treatment in syndactyly is to separate the fused digits safely, and to create a normal web space with enough cutaneous coverage. Despite many techniques have described the correction of syndactyly, skin graft still remains the annoying one. We designed the pentagonal flap from hand dorsum to reconstruct the web space reliably and try to minimize the need for skin graft. Methods: Between July 2003 and August 2005, six cases of syndactyly were corrected at UCLA Medical Center and Hallym University Sacred Heart Hospital using dorsal pentagonal flap for web space reconstruction and straight incisions for the sides of digits to minimize the need for skin graft. The proximal edge of the pentagonal flap was designed in V shape to allow for easy closure of the donor site after advancement. The pentagonal flap was advanced volarly with the underlying dermofat tissues to form a digital web. In some cases, skin defects were unavoidable and covered with full thickness skin graft from the inguinal area. Results: Syndactyly were seen in 4 cases of Apert syndrome, 1 postburn scar webbing with PIP joint contracture and 1 recurrence after the incomplete reconstruction. In all Apert syndrome, straight line incision was used along the sides of the fingers and skin graft was needed. But, in 2 cases of incomplete type, we could save the need for skin graft only for the correction of syndactyly. We could get a good looking web space without any complications such as flap or graft loss. Conclusion: As a modification of Sherif's V-Y dorsal metacarpal flap, we believe pentagonal flap could be one of the easiest and safest way to reconstruct the web space of syndactyly in functional and cosmetic standpoint.

Stereoscopic Conversion of Monoscopic Video using Edge Direction Histogram (에지 방향성 히스토그램을 이용한 2차원 동영상의 3차원 입체변환기법)

  • Kim, Jee-Hong;Yoo, Ji-Sang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.8C
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    • pp.782-789
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    • 2009
  • In this paper, we propose an algorithm for creating stereoscopic video from a monoscopic video. Parallel straight lines in a 3D space get narrower as they are farther from the perspective images on a 2D plane and finally meet at one point that is called a vanishing point. A viewer uses depth perception clues called a vanishing point which is the farthest from a viewer's viewpoint in order to perceive depth information from objects and surroundings thereof to the viewer. The viewer estimates the vanishing point with geometrical features in monoscopic images, and can perceive the depth information with the relationship between the position of the vanishing point and the viewer's viewpoint. In this paper, we propose a method to estimate a vanishing point with edge direction histogram in a general monoscopic image and to create a depth map depending on the position of the vanishing point. With the conversion method proposed through the experimental results, it is seen that stable stereoscopic conversion of a given monoscopic video is achieved.

A Study on Blended Inlet Body Design for a High Supersonic Unmanned Aerial Vehicle

  • You, Lianxing;Yu, Xiongqing;Li, Hongmei
    • International Journal of Aeronautical and Space Sciences
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    • v.17 no.2
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    • pp.260-267
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    • 2016
  • The design process of blended inlet body (BIB) for the preliminary design of a near-space high supersonic unmanned aerial vehicle (HSUAV) is presented. The mass flow rate and cowl area of inlet at a design point are obtained according to the cruise condition of the HSUAV. A mixed-compression axisymmetric supersonic inlet section with a fixed geometry reasonably matching the high supersonic cruise state is created by using the inviscid theory of aerodynamics. The inlet section is optimized and used as a baseline section for the BIB design. Three BIB concepts for the HSUAV are proposed, and their internal aerodynamic characteristics of inlet are evaluated using Euler computational fluid dynamics (Euler CFD) solver. The preferred concept is identified, in which the straight leading edge of the baseline HSUAV configuration is modified into the convex leading edge to accommodate the inlet and meet the requirements of the cowl area to capture the sufficient air flow. The total recovery of inlet for the preferred BIB concept and the aerodynamic characteristics of the modified HSUAV configuration are verified using Navier-Stokes computational fluid dynamics (NS CFD) solver. The validation indicates that the preferred BIB concept can meet both the requirements of the inlet and aerodynamic performance of the HSUAV.

A Study on the Extraction of an Individual Character and Chinese Characters Recognition on the Off-line Documents (오프라인 문서에서 개별 문자 추출과 한자 인식에 관한 연구)

  • Kim, Ui-Jeong;Kim, Tae-Gyun
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.5
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    • pp.1277-1288
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    • 1997
  • In this paper,the extraciton method for individual and the recognition method for the printed dociments are discussed. In preprocessing is a technique to extract characters that are difficult to manage such as touching characters or overlapped chracters.Genrally in the existing segmentation methods,projection and edge detection are applied.However,in this paper an indvidual character is extracted by using connected pixel with one projection after the string extraction The maximum Blok Methld(MBM)is used for the recognition.The MBM is a method to enlarge the block to the last point the pixel that was found during projection. The maximum blocks are skeletonxied after the division into straight line block and oblique line block.Especially,in the recognition of chinese chracters compared to the existing method it showed improved recognition rate.

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Hierarchical Grouping of Line Segments for Building Model Generation (건물 형태 발생을 위한 3차원 선소의 계층적 군집화)

  • Han, Ji-Ho;Park, Dong-Chul;Woo, Dong-Min;Jeong, Tai-Kyeong;Lee, Yun-Sik;Min, Soo-Young
    • Journal of IKEEE
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    • v.16 no.2
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    • pp.95-101
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    • 2012
  • A novel approach for the reconstruction of 3D building model from aerial image data is proposed in this paper. In this approach, a Centroid Neural Network (CNN) with a metric of line segments is proposed for connecting low-level linear structures. After the straight lines are extracted from an edge image using the CNN, rectangular boundaries are then found by using an edge-based grouping approach. In order to avoid producing unrealistic building models from grouping lined segments, a hierarchical grouping method is proposed in this paper. The proposed hierarchical grouping method is evaluated with a set of aerial image data in the experiment. The results show that the proposed method can be successfully applied for the reconstruction of 3D building model from satellite images.

A Study on the Dose Changes Depending on the Shielding Block Type of Irradiation During Electron Beam Theraphy (전자선치료 시 조사부위 차폐물 형태에 따른 선량변화 연구)

  • Lee, Sun-Yeb;Park, Cheol-Soo;Lee, Jae-Seung;Goo, Eun-Hoe;Cho, Jae-Hwan;Kim, Eng-Chan;Moon, Soo-Ho;Kim, Jin-Soo;Park, Cheol-Woo;Dong, Kyung-Rae;Kweon, Dae-Cheol
    • Journal of radiological science and technology
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    • v.33 no.3
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    • pp.253-260
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    • 2010
  • The primary focus of this study was to explore the variation in dose distributions of electron beams between different types of construction structure of cut-out blocks embodied in electron cones, given that the structure is considered one of the causes of multiple scattered radiation from electrons which may affect dose distributions. For evaluation, two types of cut-out blocks, divergency and straight, manufactured for this study, were compared in terms of area of interval in distribution of dose, and flatness and symmetric state of surface being radiated. The results showed that divergency cut-out blocks reduced the lateral scattering effects on the thickness of cut-out blocks more substantially than straight ones, leading to more uniform dose distribution at baseline depth. Notably in divergency cut-out blocks, the high dose area decreased more significantly, and more uniform dose distribution was observed at the edge of the irradiated field. This points to a need to consider the characteristics of dose distribution of electron beams when setting up radiotherapy planing at the venues. Therefore, this study is significant as an exploratory work for ensuring high accuracy in dose delivery for patients.

Real-Time Pipe Fault Detection System Using Computer Vision

  • Kim Hyoung-Seok;Lee Byung-Ryong
    • International Journal of Precision Engineering and Manufacturing
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    • v.7 no.1
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    • pp.30-34
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    • 2006
  • Recently, there has been an increasing demand for computer-vision-based inspection and/or measurement system as a part of factory automation equipment. In general, it is almost impossible to check the fault of all parts, coming from part-feeding system, with only manual inspection because of time limitation. Therefore, most of manual inspection is applied to specific samples, not all coming parts, and manual inspection neither guarantee consistent measuring accuracy nor decrease working time. Thus, in order to improve the measuring speed and accuracy of the inspection, a computer-aided measuring and analysis method is highly needed. In this paper, a computer-vision-based pipe inspection system is proposed, where the front and side-view profiles of three different kinds of pipes, coming from a forming line, are acquired by computer vision. And the edge detection is processed by using Laplace operator. To reduce the vision processing time, modified Hough transform is used with clustering method for straight line detection. And the center points and diameters of inner and outer circle are found to determine eccentricity of the parts. Also, an inspection system has been built so that the data and images of faulted parts are stored as files and transferred to the server.

Parallelism and Straightness Measurement of a Pair of Rails for Ultra Precision Guide-ways (초정밀 안내면 레일의 평행도 및 진직도 동시측정)

  • Hwang, Joo-Ho;Park, Chun-Hong;Wei, Gao;Kim, Seung-Woo
    • Journal of the Korean Society for Precision Engineering
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    • v.24 no.3 s.192
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    • pp.117-123
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    • 2007
  • This paper describes a three-probe system that can be used to measure the parallelism and straightness of a pair of rails simultaneously. The parallelism is measured using a modified reversal method, while the straightness is measured using a sequential two-point method. The measurement algorithms were analyzed numerically using a pair of functionally defined rails to validate the three-probe system. Tests were also performed on a pair of straightedge rails with a length of 250 mm and a maximum straightness deviation of $0.05{\mu}m$, as certified by the supplier. The experimental results demonstrated that the parallelism-measurement algorithm had a cancellation effect on the probe stage motion error. They also confirmed that the proposed system could measure the slope of a pair of rails about $0.06{\mu}rad$. Therefore, by combining this technique with a sequential differential method to measure the straightness of the rails simultaneously, the surface profiles could be determined accurately and eliminate the stage error. The measured straightness deviation of each straight edge was less than $0.05{\mu}m$, consistent with the certified value.

A Study on Constructions of the Polygons by Albrecht Dürer for Mathematics Education (알브레히트 뒤러의 정다각형 작도법 고찰)

  • Cho, Youngmi
    • Journal of Educational Research in Mathematics
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    • v.27 no.3
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    • pp.581-598
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    • 2017
  • The early Renaissance artist Albrecht $D{\ddot{u}}rer$ is an amateur mathematician. He published a book on geometry. In the second part of that book, $D{\ddot{u}}rer$ gave compass and straight edge constructions for the regular polygons from the triangle to the 16-gon. For mathematics education, I extracted base constructions of polygon constructions. And I also showed how to use $D{\ddot{u}}rer^{\prime}s$ idea in constructing divergent forms with compass and ruler. The contents of this paper can be expected to be the baseline data for mathematics education.

Recognition of Lanes, Stop Lines and Speed Bumps using Top-view Images (탑뷰 영상을 이용한 차선, 정지선 및 과속방지턱 인식)

  • Ahn, Young-Sun;Kwak, Seong Woo;Yang, Jung-Min
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.11
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    • pp.1879-1886
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    • 2016
  • In this paper, we propose a real-time recognition algorithm of lanes, stop lines and speed bumps on roads for autonomous vehicles. First, we generate a top-view using the image transmitted from a camera that is installed to see the front of a vehicle. To speed up the processing, we simplify the mapping algorithm in constructing a top-view wherein the region of interest (ROI) is concerned. The features of lanes, stop lines and speed bumps, which are composed of lines, are searched in the edge image of the top-view, then followed by labeling and clustering specialized to detect straight lines. The width of lines, distances from the center of a vehicle, and curvature of each cluster are considered to select final candidates. We verify the proposed algorithm on real roads using the commercial car (KIA K7) which is converted into an autonomous vehicle.