• Title/Summary/Keyword: KINEMATICS

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Systemic search for gas outflows in AGNs and star-forming galaxies

  • Woo, Jong-Hak;Son, Donghoon;Bae, Hyun-Jin
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.35.2-35.2
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    • 2016

  • We present a census of AGN-driven gas outflows based on the kinematics of ionized gas and stars, using a large sample of ~11,000 emission line galaxies at z < 0.3, selected from SDSS. First, a broad correlation between gas and stellar velocity dispersions indicates that the bulge gravitational potential plays a main role in determining the ionized gas kinematics. However, the velocity dispersion of the [OIII] emission line is larger than stellar velocity dispersion by a factor of 1.3-1.4, suggesting that the non-gravitational (non-virial) component, i.e., outflows, is almost comparable to the gravitational component. Second, gas-to-stellar velocity dispersion ratio increases with both AGN luminosity and Eddington ratio, suggesting that non-gravitational kinematics are clearly linked to AGN accretion. The distribution in the [OIII] velocity - velocity dispersion diagram dramatically expands toward large values with increasing AGN luminosity, implying that the launching velocity of gas outflows increases with AGN luminosity. Third, the fraction of AGNs with a signature of the non-gravitational kinematics, steeply increases with AGN luminosity and Eddington ratio, while the majority of luminous AGNs presents the non-gravitational kinematics in the [OIII] profile. These results suggest that ionized gas outflows are prevalent among type 2 AGNs. On the other hand, we find no strong trend of the [OIII] kinematics with radio luminosity, once we remove the effect of the bulge gravitational potential, indicating that ionized gas outflows are not directly related to radio activity for the majority of type 2 AGNs. We will discuss the implication of these results for AGN feedback in the local universe.

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A Study for properties of IK system to 3D character animation education (3D 캐릭터 애니메이션 교육을 위한 IK SYSTEM 특성 연구(Bone, Character Studio, CAT을 중심으로))

  • Cho, Hyung-Ik
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.10a
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    • pp.519-523
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    • 2011

  • Today, one of the most important reasons that 3D software becomes a core part of the essential tools in the video contents field like the movies, animation, CF, motion graphic, games and etc. is that they can save budget of contents makings and can produce better effects than conventional methods like miniature, matt painting, extra mobilization and etc. and can save time and have the merit that they are not limited in space. In this paper, I analyzed IK(Inverse kinematics) system characteristics for the efficient education of 3D character animation particularly most used of 3D applications which is now supposed to be nearly necessary elements in game, animation, movie and contents. And by analyzing merits and demerits of each tool on Bone, Character studio and Character Animation Toolkit, systems which are most used practically in the various Inverse kinematics tools, I showed the result of analyses about the fact that educating which of the above three Inverse Kinematics tools is helpful and beneficial for the students for the efficient education in the university where should teach much in the limited time

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Efficient Intermediate Joint Estimation using the UKF based on the Numerical Inverse Kinematics (수치적인 역운동학 기반 UKF를 이용한 효율적인 중간 관절 추정)

  • Seo, Yung-Ho;Lee, Jun-Sung;Lee, Chil-Woo
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.6
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    • pp.39-47
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    • 2010

  • A research of image-based articulated pose estimation has some problems such as detection of human feature, precise pose estimation, and real-time performance. In particular, various methods are currently presented for recovering many joints of human body. We propose the novel numerical inverse kinematics improved with the UKF(unscented Kalman filter) in order to estimate the human pose in real-time. An existing numerical inverse kinematics is required many iterations for solving the optimal estimation and has some problems such as the singularity of jacobian matrix and a local minima. To solve these problems, we combine the UKF as a tool for optimal state estimation with the numerical inverse kinematics. Combining the solution of the numerical inverse kinematics with the sampling based UKF provides the stability and rapid convergence to optimal estimate. In order to estimate the human pose, we extract the interesting human body using both background subtraction and skin color detection algorithm. We localize its 3D position with the camera geometry. Next, through we use the UKF based numerical inverse kinematics, we generate the intermediate joints that are not detect from the images. Proposed method complements the defect of numerical inverse kinematics such as a computational complexity and an accuracy of estimation.

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