• Title/Summary/Keyword: perspective projection

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Virtual Bronchoscopy for Diagnosis of Tracheo-Bronchial Disease (기관지질환 진단을 위한 가상내시경)

  • Kim, Do-Yeon;Park, Jong-Won
    • The KIPS Transactions:PartB
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    • v.10B no.5
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    • pp.509-514
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    • 2003
  • The virtual bronchoscopy was implemented using chest CT images to visualize inside of tracheo-bronchial wall. The optical endoscopy procedures are invasive, uncomfortable for patients and sedation or anesthesia may be required. Also, they have serious side effects such as perforation, infection and hemorrhage. In order to determine the navigation path, we segmented the tracheo-bronchial wall from the chest CT image. We used the coordinates as a navigation path for virtual camera that were calculated from medial axis transformation. We used the perspective projection and marching cube algorithm to render the surface from volumetric CT image data. The tracheobronchial disease was classified into tracheobronchial stenosis causing from inflammation or lung cancer, bronchiectasis and bronchial cancer. The virtual bronchoscopy is highly recommended as a diagnosis tool with which the specific place of tracheobronchial disease can be identified and the degree of tracheobronchial disease can be measured qualitatively, Also, the virtual bronchoscopy can be used as an education and training tool for endoscopist and radiologist.

011-line Visual Feedback Control of Industrial Robot Manipulator (산업용 로봇 매니퓰레이터의 오프라인 영상피드백 제어)

  • 신행봉;정동연;김용태;이종두;이강두
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.04a
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    • pp.567-572
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    • 2002
  • The equipment of industrial robot in manufacturing and assembly lines has rapidly increased. In order to achieve high productivity and flexibility, it becomes very important to develop the visual feedback control system with Off-Line Programming System(OLPS ). We can save much efforts and time in adjusting robots to newly defined workcells by using Off-Line Programming System. A proposed visual calibration scheme is based on position-based visual feedback. The visual calibration system is composed of a personal computer, an image processing board, a video monitor, and one camera. The calibration program firstly generates predicted images of objects in an assumed end-effector position. The process to generate predicted images consists of projection to screen-coordinates, visible range test, and construction of simple silhouette figures. Then, camera images acquired are compared with predicted ones for updating position and orientation data. Computation of error is very simple because the scheme is based on perspective projection, which can be also expanded to experimental results. Computation time can be extremely reduced because the proposed method does not require the precise calculation of tree-dimensional object data and image Jacobian.

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Off-line Visual Feedback Control of Robot Manipulator (로봇 매니퓰레이터의 오프라인 영상피드백 제어)

  • 신행봉;정동연;이종두;이강두;한성현
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2001.10a
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    • pp.140-145
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    • 2001
  • The equipment of industrial robot in manufacturing and assembly lines has rapidly increased. In order to achieve high productivity and flexibility, it becomes very important to develop the visual feedback control system with Off-Line Programming System(OLPS). We can save much efforts and time in adjusting robots to newly defined workcells by using Off-Line Programming System. A proposed visual calibration scheme is based on position-based visual feedback. The visual calibration system is composed of a personal computer, an image processing board, a video monitor, and one camera. The calibration program firstly generates predicted images of objects in an assumed end-effector position. The process to generate predicted images consists of projection to screen-coordinates, visible range test, and construction of simple silhouette figures. Then, camera images acquired are compared with predicted ones for updating position and orientation data. Computation of error is very simple because the scheme is based on perspective projection, which can be also expanded to experimental results. Computation time can be extremely reduced because the proposed method does not require the precise calculation of tree-dimensional object data and image Jacobian.

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A Real-Time Control of SCARA Robot Based Image Feedback (이미지 피드백에 의한 스카라 로봇의 실시간 제어)

  • Lee, Woo-Song;Koo, Young-Mok;Shim, Hyun-Seok;Lee, Sang-Hoon;Kim, Dong-Yeop
    • Journal of the Korean Society of Industry Convergence
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    • v.17 no.2
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    • pp.54-60
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    • 2014
  • The equipment of SCARA robot in processing and assembly lines has rapidly increased. In order to achieve high productivity and flexibility, it becomes very important to develop the visual feedback control system with Off-Line Programming System(OLPS). We can save much efforts and time in adjusting robots to newly defined workcells by using OLPS. A proposed visual calibration scheme is based on position-based visual feedback. The calibration program firstly generates predicted images of objects in an assumed end-effector position. The process to generate predicted images consists of projection to screen-coordinates, visible range test, and construction of simple silhouette figures. Then, camera images acquired are compared with predicted ones for updating position and orientation data. Computation of error is very simple because the scheme is based on perspective projection, which can be also expanded to experimental results. Computation time can be extremely reduced because the proposed method does not requirethe precise calculation of tree-dimensional object data and image Jacobian.

Development of Chameleonic Multi-Surface Display with Dynamic Projection Mapping (동적 실물영상투사 카멜레온(다변) 멀티 서피스 콘텐츠 연구)

  • Hong, Sung-Dae
    • Journal of Digital Contents Society
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    • v.18 no.1
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    • pp.123-132
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    • 2017
  • The physical display technology is the ultimate display technology that human beings aspire, and the world makes use of laser, plasma and reflector plate. Besides, technology development of binocular stereoscopic display has been actively progressed, but there is a limitation to the intact physical representation such as influence of optical ambient light and brightness. In this paper, the display technology using physical deformation different from the existing optical display is approached as a cultural and emotional perspective. The purpose of this paper is to develop the multivariate display technology that can create 3D realistic stereoscopic images through projecting dynamic images on physically diversified screen by overcoming the limitations of 2D planar digital signage and study how to apply them to video, exhibition and performance.

Improve Compression Efficiency of 360degree VR Video by Correcting Perspective in Cubemap Projection (Cubemap Projection 360도 VR 비디오에서 시점 보정을 통한 압축 효율 향상 방법)

  • Yoon, Sung Jea;Park, Gwang Hoon
    • Journal of Broadcast Engineering
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    • v.22 no.1
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    • pp.136-139
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    • 2017
  • Recently, many companies and consumers has shown a lot of interest toward VR(Virtual Reality), so many VR devices such as HMD(Head mounted Display) and 360 degree VR camera are released on the market. Current encoded 360 degree VR video uses the codec which originally made for the conventional 2D video. Therefore, the compression efficiency isn't optimized because the en/decoder does not consider the characteristics of the 360 degree VR video. In this paper, we propose a method to improve the compression efficiency by using the reference frame which compensates for the distortions caused by characteristics the 360 degree VR video. Applying the proposed method we were able to increase the compression efficiency by providing better prediction.

Comparative Analysis from Perspective of Kinesiology between Korean Athletes and Gold and Bronze Medalists in Glide-Type Shot Put at Daegu World Athletic Championships in 2011 (2011 대구세계육상선수권대회 Gilde Type 포환던지기 한국선수와 결승 1, 3위 선수와의 운동학적 비교분석)

  • Oh, Chow-Hwan;Choi, Su-Nam;Shin, Eui-Su;Lee, Jeong-Tae;Jeong, Ik-Su;Bae, Jae-Hee;Park, Seung-Bum
    • Korean Journal of Applied Biomechanics
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    • v.21 no.5
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    • pp.645-652
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    • 2011
  • The purpose of this study was to analyze, in real time, the glide motion and release motion of domestic athletes and gold and bronze medalists employing the glide technique for the men's shot put at the Daegu World Athletic Championship in 2011. In the glide motion, the Korean athletes had a relatively high body center and shot put heights and lager stretching angles for their hips and knees. In the delivery phase, which shifts to the release phase, the Korean athletes showed slower vertical body center and shot put speeds, and they changed the phase, to the release phase by using a small body angle. In the release phase, the Korean athletes showed differences in their projection speeds and vertical body center speeds. The world-famous players showed high angle speeds, which refer to the composition of the rotation force at the moment of release (body, hip, and shoulder line). In the release phase, the Korean athletes did not have fully stretched hip and knee angles, which might have negatively influenced the vertical speed. Because the Korean athletes showed relatively low projection heights and projection angles. it was found that they need to enhance the muscular power of their, throwing arms and lower limbs.

A statistical model for interview score based on projection (사영에 근거한 면접 점수의 통계적 모형)

  • Park, Cheol-Yong;Kim, Hyun-Wook
    • Journal of the Korean Data and Information Science Society
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    • v.23 no.3
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    • pp.495-504
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    • 2012
  • In this study, we propose a statistical model based on projection that generates interview scores. In this model, each interviewee's true score and its related variable are viewed as X, Y values respectively in the two dimensional plane, and each interviewer's score is the projected score of true score X to the axis rotated by some angle, which reflects the interviewer's perspective. Each interviewer's observed interview score is obtained by adding personal bias and observed error to this projected score. We compared commonly used standardizing methods of interview scores such as trimmed mean method, rank method, and z-score method based on the proposed statistical model. In this simulation, two types of interview methods, two numbers of interviewers, two degrees of interviewers' expertise and two distributions and three correlations between actual score and its related variable are all considered.

Between Man and Animal: Figuration of Animals in Children's Literature Focused on The Wind in the Willows (인간과 동물 사이 -아동문학의 동물 형상화 『버드나무 사이로 부는 바람』을 중심으로)

  • Kang, Gyu Han
    • Journal of English Language & Literature
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    • v.56 no.1
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    • pp.79-101
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    • 2010
  • In "The Animal That Therefore I Am (More to Follow)," Derrida notices that he is being watched by his cat. He becomes ashamed of being naked in front of his cat. The sense of shame is a response to being reduced to the level of an animal. He is ashamed of being as naked as an animal. His next move is, therefore, to cover his nakedness from the gaze of his cat. By contrast, he realizes, the animal is not self-conscious of being naked and so does not shield its nudity. In a truer sense, then, the cat is not naked. Humans do not see animals for what they really are but what they project on them. Whereas the gap between man and animal is clearly identified by Derrida's philosophical discourse, the possibility of going beyond the gap can be suggested by fantasy stories in children's literature. Children's literature in Britain arose in the eighteenth century with the revival of traditional fairy tales and growth of literary fairy tales. Romanticism in the early nineteenth century contributed to opening up a new horizon for the concept of the child, in which the child is no longer defined as the object to be tamed and childhood imagination is glorified as a powerful means to reach the higher state, the spiritual origin prior to separation of Man from the 'thing-in-itself.' In The Wind in the Willows, animals talk and behave like humans. The anthropomorphic figuration of animals can be understood as a result of the one-sided projection of anthropocentric perspectives on animals rather than an interaction between humans and animals. Significant contradictions also emerge in this story, however, as traits particular to animals are vividly delineated even as the main didactic theme of good triumphing over evil reflects an anthropocentric projection on animals. An attempt to capture the true characteristics of animals and locate them in the text constitutes a remarkable achievement in The Wind in the Willows. This can be evaluated as an important step toward a more ecopocentric perspective on animals which appears in later children's fantasies like Charlotte's Web.

Stereo Vision Based 3D Input Device (스테레오 비전을 기반으로 한 3차원 입력 장치)

  • Yoon, Sang-Min;Kim, Ig-Jae;Ahn, Sang-Chul;Ko, Han-Seok;Kim, Hyoung-Gon
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.39 no.4
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    • pp.429-441
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    • 2002
  • This paper concerns extracting 3D motion information from a 3D input device in real time focused to enabling effective human-computer interaction. In particular, we develop a novel algorithm for extracting 6 degrees-of-freedom motion information from a 3D input device by employing an epipolar geometry of stereo camera, color, motion, and structure information, free from requiring the aid of camera calibration object. To extract 3D motion, we first determine the epipolar geometry of stereo camera by computing the perspective projection matrix and perspective distortion matrix. We then incorporate the proposed Motion Adaptive Weighted Unmatched Pixel Count algorithm performing color transformation, unmatched pixel counting, discrete Kalman filtering, and principal component analysis. The extracted 3D motion information can be applied to controlling virtual objects or aiding the navigation device that controls the viewpoint of a user in virtual reality setting. Since the stereo vision-based 3D input device is wireless, it provides users with a means for more natural and efficient interface, thus effectively realizing a feeling of immersion.