• 제목/요약/키워드: Blob

검색결과 146건 처리시간 0.022초

Lyman alpha emitting blobs at the epoch of cosmic reionization

  • Kim, Hyo Jeong;Ahn, Kyungjin
    • 천문학회보
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    • 제41권2호
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    • pp.35.2-35.2
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    • 2016
  • Lyman alpha photons emitted from the early generation galaxies are scattered through the intergalactic medium, and can be observed as Lyman alpha emitting sources. We examine the Lyman alpha line transfer mechanism by tracing the random scattering histories of Lyman alpha photons in the intergalactic medium of the early universe. The density and ionization fields are based on the 3D map by N-body + radiation transfer simulations of the epoch of reionization. The calculation is compared with analytical models, too. The emergent line profile and the size of the Lyman alpha blob are strongly tied to the density and ionization environment, likely to give constraints when high-z Lyman alpha blobs are observed.

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Recognition of Patterns and Marks on Monitor Glass Panel

  • Ahn, In-Mo;Kang, Dong-Joong;Lee, Kee-Sang
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.99.2-99
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    • 2002
  • Contents 1 In this paper a machine vision system for recognizing and classifying the patterns and marks engraved by die molding or laser marking on glass panel of computer monitor is suggested and evaluated experimentally. The vision system is equipped with a neural network based pattern classifier and searching process based on normalized grayscale correlation and adaptive binarization, which is applicable to the cases in which the segmentation of the pattern area from background using the ordinary blob coloring technique is quite difficult. Inspection process is accomplished via the way of NGC hypothesis and ANN verification. The proposed pattern recognition system is composed of three...

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수평 보텍스 링의 동적 특성에 대한 3차원 수치해석 및 실험 (Three Dimensional CFD and Experiment Study on the Dynamic Characteristics of a Horizontal Vortex Ring)

  • 여창호;서용권
    • 한국가시화정보학회:학술대회논문집
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    • 한국가시화정보학회 2004년도 추계학술대회 논문집
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    • pp.26-29
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    • 2004
  • In this paper, we report the numerical and experimental solutions of the dynamic characteristics of a vortex ring in a circular cylinder generated by impinging a fluid blob from a hole on the bottom wall of the cylinder. We managed to visualize successfully the flow pattern shown on the vertical and horizontal planes by using a specially designed optical apparatus. Results of three-dimensional computation for the flow are shown to be in a satisfactory agreement with the experimental ones. We also report the experimental results which show a breaking of the axi-symmetric pattern after the vortex touches the free surface.

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GMS: 공간 데이터베이스 관리 시스템 (GMS: Spatial Database Management System)

  • 박상근;박순영;정원일;김명근;배해영
    • 한국GIS학회:학술대회논문집
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    • 한국GIS학회 2003년도 공동 춘계학술대회 논문집
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    • pp.217-224
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    • 2003
  • 전통적인 관계형 데이터베이스 시스템에서 관리되고 있는 일반적인 데이터가 아닌 점, 선, 다각형 등의 다양한 공간 데이터를 관리하기 위해서는 확장된 형태의 공간데이터 타입 및 대용량성과 다양한 접근 패턴을 지니는 공간데이터의 특성을 고려한 새로운 데이터베이스 관리 시스템이 요구된다. 본 논문에서는 이와 같은 공간데이터의 특성을 고려한 저장 기법과 공간질의 처리기법을 제공하는 공간 데이터베1이스 관리 시스템인 GMS를 제안한다. GMS는 다양한 크기를 지니는 공간데이터의 특성을 고려하여 공간/비공간 통합 저장관리 및 BLOB 데이터 저장기법을 제공하며, 저장된 공간/비공간 데이터에 대한 다양한 색인기법을 제공하고 있다. 그밖에 공간 연산 및 복잡한 질의처리를 위해 확장된 질의 최적화 및 질의처리 기법을 제공하며, 다중 사용자를 위한 확장된 동시성 제어 기법과 공간/비공간 데이터에 대한 서로 다른 회복 기법을 제공한다.

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Studying confined polymers using single-molecule DNA experiments

  • Hsieh, Chih-Chen;Doyle, Patrick S.
    • Korea-Australia Rheology Journal
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    • 제20권3호
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    • pp.127-142
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    • 2008
  • The development of fluorescence microscopy of single-molecule DNA in the last decade has fostered a bold jump in the understanding of polymer physics. With the recent advance of nanotechnology, devices with well-defined dimensions that are smaller than typical DNA molecules can be readily manufactured. The combination of these techniques has provided an unprecedented opportunity for researchers to examine confined polymer behavior, a topic far less understood than its counterpart. Here, we review the progress reported in recent studies that investigate confined polymer dynamics by means of single-molecule DNA experiments.

이화학적 살균제로 처리한 Campylobacter jejuni의 세포 형타와 미세구조에 대한 전자현미경적 연구 (Electron Microscopic Studies on the Morphology and Ultrastructures in Campylobacter jejuni treated with Physico-chemical Disinfectants)

  • 윤만석;오학식;김치경
    • Applied Microscopy
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    • 제19권2호
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    • pp.17-26
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    • 1989
  • The cells of Campylobacter jejuni treated with physical or chemical disinfection agents were comparatively examined by scanning and transmission electron microscopies for their morphological features and internal ultrastructures. The normal cells of C. jejuni, showed typical spiral rod shapes. The ribosomes, nucleoids, and other cellular constituents were observed to be distributed evenly throughout the cytoplasm. The cells treated with heat or UV-light were changed to spherical or irregular shapes and their cell envelopes were destroyed to form ghost cells by liberating their cytoplasmic components. The cells treated with chlorine or monochloramine were also changed into irregular round shapes. The chlorinated cells showed very rough surface structures with many blob-like protrusions, while the surface of the monochloramine-treated cells appeared to be relatively smooth.

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Light Source Target Detection Algorithm for Vision-based UAV Recovery

  • Won, Dae-Yeon;Tahk, Min-Jea;Roh, Eun-Jung;Shin, Sung-Sik
    • International Journal of Aeronautical and Space Sciences
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    • 제9권2호
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    • pp.114-120
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    • 2008
  • In the vision-based recovery phase, a terminal guidance for the blended-wing UAV requires visual information of high accuracy. This paper presents the light source target design and detection algorithm for vision-based UAV recovery. We propose a recovery target design with red and green LEDs. This frame provides the relative position between the target and the UAV. The target detection algorithm includes HSV-based segmentation, morphology, and blob processing. These techniques are employed to give efficient detection results in day and night net recovery operations. The performance of the proposed target design and detection algorithm are evaluated through ground-based experiments.

디지털 조형의 혼성적 특성연구 (Hybridization in Digital Geometry)

  • 김란희;안성모
    • 한국실내디자인학회논문집
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    • 제23권4호
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    • pp.129-139
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    • 2014
  • The objective of this research is to suggest new geometric possibilities in digital architecture by investigating the characteristics of hybridization in digital geometry. The research begins with theoretical background research such as defining hybridization, investigating hybrid thinking, and studying the theory of digital geometry, along with the four conceptual characteristics of hybridization that could be drawn, such as temporality, liquidity, complexity, and connectivity. Based on these characteristics, the generative method of hybrid digital geometric languages such as Blob, Particle, Morph, Loft, and Boolean was analyzed with case research in contemporary digital architecture. As a result, diverse hybrid geometric keywords were extracted; these keywords suggest potential meanings of hybridization such as accidentality, mobility, diversity, and identity. Different elements represent the "mobility" in time by the force and wave, and they are "accidentally" combined in gradual change. The united species in "diverse" characters are seamlessly connected and emerge as a new "identity." The research maximizes the generative possibilities in digital geometry and provides a theoretical basis to apply the digital hybrid methods to architectural design by suggesting the potential meanings and possibilities in hybridization.

심장의 수축 및 이완기에서의 좌심실 벽 움직임 시뮬레이션 (The left ventricle wall motion simulation during systolic and diastolic stages of the heart)

  • 최수미
    • 한국시뮬레이션학회:학술대회논문집
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    • 한국시뮬레이션학회 1999년도 춘계학술대회 논문집
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    • pp.138-142
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    • 1999
  • 심장의 수축 및 이완기에서의 좌심실 벽 움직임은 허혈 및 심근경색증과 같은 심장질환에서 영상적 진단의 주요한 특징이다. 심장은 동적 기관으로써 진단을 위해서는 속도와 같은 4차원 파라미터의 추정이 필요하다. 본 논문에서는 심장의 좌심실 형태 및 움직임을 모델링하여 동적으로 가시화하는 방법을 제시한다. 본 논문에서는 좌심실을 Dynamic Gaussian Blob 모델로 근사화하였다. 이 모델은 가우시안 함수 기반 FEM 요소와 superellipsoid를 통합한 것으로 좌심실의 형태 및 벽의 움직임을 물리기반 방법에 의해 묘사할 수 있다. 즉, 일련의 영상들로부터 좌심실 벽에 대응되는 3차원 점들을 추출한 후 이 점들에 작용되는 힘에 의해 박동하는 좌심실의 움직임을 추적한다. 이와 같은 좌심실 벽 움직임 시뮬레이션은 심장 움직임에 이상이 있는 질환의 진단을 위한 빠르고 간편한 보조 도구로써 사용되어질 수 있다.

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수색 구조 로봇을 위한 적외선 영상 기반 인명 인식 (Infrared Image Based Human Victim Recognition for a Search and Rescue Robot)

  • 박정길;이근재;박재병
    • 제어로봇시스템학회논문지
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    • 제22권4호
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    • pp.288-292
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    • 2016
  • In this paper, we propose an infrared image based human victim recognition method for a search and rescue robot in dark environments, like general disaster situations. For recognizing a human victim, an infrared camera on a RGB-D camera, Microsoft Kinect, is used. The contrast and brightness of the infrared image are first improved by histogram equalization, and the noise on the image is removed by morphological operation and Gaussian filtering. For recognizing a human victim, the binarization and blob labeling methods are applied to the improved image. Finally, for verifying the effectiveness and feasibility of the proposed method, an experiment for human victim recognition is carried out in a dark environment.