• 제목/요약/키워드: Body motion

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다중 시점 영상 시퀀스를 이용한 강인한 행동 인식 (Robust Action Recognition Using Multiple View Image Sequences)

  • 아마드;이성환
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2006년도 가을 학술발표논문집 Vol.33 No.2 (B)
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    • pp.509-514
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    • 2006
  • Human action recognition is an active research area in computer vision. In this paper, we present a robust method for human action recognition by using combined information of human body shape and motion information with multiple views image sequence. The principal component analysis is used to extract the shape feature of human body and multiple block motion of the human body is used to extract the motion features of human. This combined information with multiple view sequences enhances the recognition of human action. We represent each action using a set of hidden Markov model and we model each action by multiple views. This characterizes the human action recognition from arbitrary view information. Several daily actions of elderly persons are modeled and tested by using this approach and they are correctly classified, which indicate the robustness of our method.

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유정압 테이블의 동적 Modeling에 관한 연구 (A Study on the Dynamic Modeling of a Hydrostatic Table)

  • 노승국;이찬홍;박천홍
    • 한국정밀공학회지
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    • 제15권3호
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    • pp.150-156
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    • 1998
  • In this paper, a 3-DOF(Degree Of Freedom) rigid body model is developed for dynamic analysis of a hydrostatic table. The dynamic coefficients, stiffness and damping constant of each pad are calculated from the mass flow continuity condition. The validity of this model is examined in theoretical and experimental method. The dynamic behavior when mass unbalances and local variations of stiffness and damping of pads present is analyzed for real applications of hydrostatic table. Since the theoretical and experimental results show goof agreement. it can be said that the 3-DOF rigid body model is useful for the dynamic model of the table. The analysis reveals that the pitching motion is the dominant mode of vibration, It also reveals that unbalanced loads can increase amplitude of tilting motion and reduce natural frequencies and damping capacity of the hydrostatic table.

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화물창의 유체유동을 고려한 선체운동에 관한 연구 (A study on the Motions of a ship with Liquid Cargo Tanks)

  • 박명규;김순갑;김동준
    • 한국항해학회지
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    • 제10권2호
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    • pp.139-155
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    • 1986
  • In this paper the dynamic effects due to the free water motions in tanks upon the lateral motion of a floating body in regular waves are calculated, in order to obtain the relationship between a motion of a floating body and that of the free water in tanks. Under the assumption that the fluid is ideal and motion amplitudes are small, velocity potential of the fluid in tanks is calculated by the source distribution method and the hydrodynamic forces and moments are calculated by the integration of fluid pressures over the tank surface. Hydrodynamic effects of the fluid on the floating body are expressed in terms of added mass and coupling coefficient obtained from the integration. Computations are carried out for ship with seven wide center tanks and comparisons between the liquid cargo loading case and the rigid cargo loading case are shown.

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기능적전기자극에 의한 체간제어의 기초적인 연구 (FUNDAMENTAL STUDY FOR ROLLING-OVER MOTION OF THE BODY BY FUNCTIONAL ELECTRICAL STIMULATION(FES))

  • 이준하;호시미야
    • Journal of Yeungnam Medical Science
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    • 제7권2호
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    • pp.103-108
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    • 1990
  • 기능적전기자극(FES)을 이용하여 중추신경장해환자의 체간제어를 행하는 방법을 고안하여 체간제어에 필요한 각 각의 관절운동을 실현시켜 보았다. 건강인에게 전기자극실험을 행하고 기능적전기자극애 의해 체위변환의 실현가능성을 검증했다. 또한 상지를 함께 이용한 체위변환시의 근전도를 해석하여 보다 적절한 체위변환의 방법을 검토했다.

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선박용 프로펠러의 종방향 강체운동에 대한 부가질량 (The Added Mass and Damping for the Axial Rigid Body Motion of a Marine Propeller Rotating in a Uniform Flow)

  • 김영중;이현엽;이창섭
    • 대한조선학회논문집
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    • 제45권3호
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    • pp.309-314
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    • 2008
  • An experimental method to estimate the added mass of a marine propeller has been developed for the axial rigid body motion in still water, and the experiments have been carried out. The experimental result has been compared to the theoretical result by PRODAS based on the unsteady lifting surface theory. The experimental method developed in this research and the theoretical method by PRODAS have been validated by confirming good agreements between the experimental results and the theoretical ones. Also the comparison to the results by empirical formula has been made and discussed.

Aerodynamic Charasteristics of Tumbling-Rectangular-Flat Plate Under Free Flight

  • Shimizu, Kosuke;Funaki, Jiro;Hirata, Katsuya
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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    • pp.353-356
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    • 2004
  • When a body falls in fluid, the body often experiences autorotations, namely, various kind of rotating motions, such as tumbling, flat spin and coming. Tumbling is a rotating motion with an axis perpendicular to a falling direction. Tumbling is a very important phenomenon in aeronautical and space engineering, ballistics and meteorology. For example, when an satellite re-en-tries into the atomosphere, its body collapses into many fragments which are disperse in the wide range of field. Some fragments fall in tumbling motion. Then tumbling is useful to predict fragment's motion.(omitted)

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A novel technique for removing the rigid body motion in interior BVP of plane elasticity

  • Y. Z. Chen
    • Advances in Computational Design
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    • 제9권1호
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    • pp.73-80
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    • 2024
  • The aim of this paper is to remove the rigid body motion in the interior boundary value problem (BVP) of plane elasticity by solving the interior and exterior BVPs simultaneously. First, we formulate the interior and exterior BVPs simultaneously. The tractions applied on the contour in two problems are the same. After adding and subtracting the two boundary integral equations (BIEs), we will obtain a couple of BIEs. In the coupled BIEs, the properties of relevant integral operators are modified, and those integral operators are generally invertible. Finally, a unique solution for boundary displacement of interior region can be obtained.

이족보행로봇의 횡보행 경로생성을 위한 시뮬레이터 연구 (Study on a Simulator for Generating Side Walking Path of the Biped Walking Robot)

  • 최형식;전창훈;강진일
    • Journal of Advanced Marine Engineering and Technology
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    • 제32권8호
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    • pp.1285-1295
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    • 2008
  • A research on a simulator for a side walking path of a 16 degree-of-freedom (d.o.f) biped walking robot(BWR) which is composed of 4 d.o.f upper-part body and 12 d.o.f lower-part of the body is presented. For generation of stable side walking motion, the kinematics, dynamics and the zero moment of point(ZMP) of the BWR were analyzed analytically and included in the simulator. To operate the motion simulator for stable side walking of the BWR, a graphic user interface program was developed which needs inputs for the side distance between legs, base joint angle, walking type, and walking velocity. The simulator was developed to generate joint angle data of legs for side walking, and the data are transmitted to the BWR for stable side walking. In the simulator, a new path function for smooth walking motion was proposed and applied to the simulator and actual motion of a BWR. Also for actual side walking, an algorithm for estimating backlashes of the actuating joint motors was proposed and included in the simulator. To validate the performance of the proposed motion simulator, the simulator was operated and its side walking data of the simulator were generated for a period of side walking.

Dynamics Modeling and Simulation of Korean Communication, Ocean, and Meteorology Satellite

  • No, Tae-Soo;Lee, Sang-Uk;Kim, Sung-Ju
    • International Journal of Aeronautical and Space Sciences
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    • 제8권2호
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    • pp.89-97
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    • 2007
  • COMS(Communication, Oceanography, and Meteorology Satellite) is the first Korean multi-purpose satellite which is planned to be deployed at the altitude of geosynchronous orbit above the Korean peninsular. Noting that COMS is composed of the main BUS structure, two deployable solar panels, one yoke, five reactions wheels, COMS is treated as a collection of 9 bodies and its nonlinear equations of motion are obtained using the multi-body dynamics approach. Also, a computer program is developed to analyze the COMS motion during the various mission phase. Quite often, the equations of motion have to be derived repeatedly to reflect the fact that the spacecraft dynamics change as its configuration, and therefore its degree of freedom varies. However, the equations of motion and simulation software presented in this paper are general enough to represent the COMS dynamics of various configurations with a minimum change in input files. There is no need to derive the equations of motion repeatedly. To show the capability of the simulation program, the spacecraft motion during the solar array partial and full deployment has been simulated and the results are summarized in this paper.

기저부 유동 및 난류가 다단 로켓의 단 분리 운동에 미치는 영향 (EFFECT OF BASE FLOW AND TURBULENCE ON THE SEPARATION MOTION OF STRAP-ON ROCKET BOOSTERS)

  • 고순흠;김재관;한상호;김진호;김종암
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2007년도 춘계 학술대회논문집
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    • pp.83-86
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    • 2007
  • Turbulent flow analysis is conducted around the multi-stage launch vehicle including base region and detachment motion of strap-on boosters due to resultant aerodynamic forces and gravity is simulated. Aerodynamic solution procedure is coupled with rigid body dynamics for the prediction of separation behavior. An overset mesh technique is adopted to achieve maximum efficiency in simulating relative motion of bodies and various turbulence models are implemented on the flow solver to predict the aerodynamic forces accurately. At first, some preliminary studies are conducted to show the importance of base flow for the exact prediction of detachment motion and to find the most suitable turbulence model for the simulation of launch vehicle configurations. And then, developed solver is applied to the simulation of KSR-III, a three-stage sounding rocket researched in Korea. From the analyses, after-body flow field strongly affects the separation motions of strap-on boosters. Negative pitching moment at initial stage is gradually recovered and a strap-on finally results in a safe separation, while fore-body analysis shows collision phenomena between core rocket and booster. And a slight variation of motion is observed from the comparison between inviscid and turbulent analyses. Change of separation trajectory based on viscous effects is just a few percent and therefore, inviscid analysis is sufficient for the simulation of separation motion if the study is focused only on the movement of strap-ons.

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