• Title/Summary/Keyword: internal motion

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Optical Tracking of Three-Dimensional Brownian Motion of Nanoparticles

  • Choi C. K.;Kihm K.D.
    • Journal of the Korean Society of Visualization
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    • v.3 no.1
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    • pp.3-19
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    • 2005
  • Novel optical techniques are presented for three-dimensional tracking of nanoparticles; Optical Serial Sectioning Microscopy (OSSM) and Ratiometric Total Internal Reflection Fluorescent Microscopy (R-TIRFM). OSSM measures optically diffracted particle images, the so-called Point Spread Function (PSF), and dotermines the defocusing or line-of-sight location of the imaged particle measured from the focal plane. The line-of-sight Brownian motion detection using the OSSM technique is proposed in lieu of the more cumbersome two-dimensional Brownian motion tracking on the imaging plane as a potentially more effective tool to nonintrusively map the temperature fields for nanoparticle suspension fluids. On the other hand, R-TIRFM is presented to experimentally examine the classic theory on the near-wall hindered Brownian diffusive motion. An evanescent wave field from the total internal reflection of a 488-nm bandwidth of an argon-ion laser is used to provide a thin illumination field of an order of a few hundred nanometers from the wall. The experimental results show good agreement with the lateral hindrance theory, but show discrepancies from the normal hindrance theory. It is conjectured that the discrepancies can be attributed to the additional hindering effects, including electrostatic and electro-osmotic interactions between the negatively charged tracer particles and the glass surface.

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Shoulder and Hip Joint Range of Motion in Normal Adults (정상 성인의 견, 고관절 가동범위에 대한 조사)

  • Ham, Yong-Woon
    • The Journal of Korean Physical Therapy
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    • v.3 no.1
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    • pp.97-108
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    • 1991
  • The purpose of this article is to know the standard figures of joint range of motion, in conjuction with age and sen, for normal adults. The results of assessment and analysis io shoulder and hip joint range of motion are as follows : 1) The average shoulder joint range of motion in normal adults are $160.5^{\circ}$ in flexion, $53.5^{\circ}$ in extension, $159.3^{\circ}$ in adduction, $62.3^{\circ}$ in internal rotation, $83.9^{\circ}$ in external rotation, The average hip joint range of motions are $116.8^{\circ}$ in flexion, $16.1^{\circ}$ in extension, $41.1^{\circ}$ in abduction, $33.8^{\circ}$ in abduction, $40.0^{\circ}$ in interne rotation, $41.2^{\circ}$ in external rotation. 2) There is no significant difference in shoulder and hip joint range of motion between male and female (p>0.05). 3) As to the inter-relation in age and range of motion, the left flexion and extension, internal rotation and right extension in shoulder joint is decreased gradually with increasing age, and left flexion (knee flexion, knee extension) and right flexion (knee extension) in hip joint is decreased with increasing age (p<0.01). 4) Relating to age and sex, the twenties male shows highest range of motion in shoulder and hip joint, with .the fifties female shows, lowest range of motion.

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Landing Motion Analysis of Human-Body Model Considering Impact and ZMP Condition (충격과 ZMP 조건을 고려한 인체 모델의 착지 동작 해석)

  • So Byung Rok;Kim Wheekuk;Yi Byung-Ju
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.6
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    • pp.543-549
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    • 2005
  • This paper deals with modeling and analysis fer the landing motion of a human-body model. First, the dynamic model of a floating human body is derived. The external impulse exerted on the ground as well as the internal impulse experienced at the joints of the human body model is analyzed. Second, a motion planning algorithm exploiting the kinematic redundancy is suggested to ensure stability in terms of ZMP stability condition during a series of landing phases. Four phases of landing motion are investigated. In simulation, the external and internal impulses experienced at the human joints and the ZMP history resulting from the motion planning are analyzed for two different configurations. h desired landing posture is suggested by comparison of the simulation results.

Comparison of Protein Internal Motion by Inter-helical Motional Correlations and Hydrogen Bond Ratio

  • Kim, Byoung-Kook;Yoon, Chang-No
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • 2005.09a
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    • pp.305-310
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    • 2005
  • Internal motion of the protein has been described in many papers with C$_{\alpha}$ correlation coefficients to find motional correlation and functional characteristics. To describe the secondary structural motion and stability in protein, we have studied molecular dynamics (MD) simulations on FADD Death Domain and FADD Death Effector Domain which have a similar structure but have different functional characteristics. After 10ns MD simulations, the inter-helical motional correlations and the hydrogen bond ratios were compared between the two domains. From these data we could distinctly compare the internal motions of them and could explain the differences in experimental thermodynamic melting behaviors at molecular level.

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High-accuracy Motion Control of Linear Synchronous Motor (선형 동기 모터의 정밀모션 제어)

  • Jeong Seong Hyun;Sung Jun Yup;Park Jung Il
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.6 s.171
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    • pp.76-82
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    • 2005
  • In this paper, the pole placement controller based on the Robust Internal-loop Compensator (RIC) structure, which has inherent structural equivalence to disturbance observer, is proposed to control a linear positioning system. This controller has the advantage to easily select controller gains by using pole placement without loss of that of original RIC structure. The principal is to construct the pole placement controller for a nominal internal model instead of unknown real plant. Using linear motion experiment showed the effectiveness of the proposed controller.

Effect of Internal Fluid Resonance on the Performance of a Floating OWC Device

  • Cho, Il Hyoung
    • Journal of Ocean Engineering and Technology
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    • v.35 no.3
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    • pp.216-228
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    • 2021
  • In the present study, the performance of a floating oscillating water column (OWC) device has been studied in regular waves. The OWC model has the shape of a hollow cylinder. The linear potential theory is assumed, and a matched eigenfunction expansion method(MEEM) is applied for solving the diffraction and radiation problems. The radiation problem involves the radiation of waves by the heaving motion of a floating OWC device and the oscillating pressure in the air chamber. The characteristics of the exciting forces, hydrodynamic forces, flow rate, air pressure in the chamber, and heave motion response are investigated with various system parameters, such as the inner radius, draft of an OWC, and turbine constant. The efficiency of a floating OWC device is estimated in connection with the extracted wave power and capture width. Specifically, the piston-mode resonance in an internal fluid region plays an important role in the performance of a floating OWC device, along with the heave motion resonance. The developed prediction tool will help determine the various design parameters affecting the performance of a floating OWC device in waves.

Dynamic responses of a riser under combined excitation of internal waves and background currents

  • Lou, Min;Yu, Chenglong
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.6 no.3
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    • pp.685-699
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    • 2014
  • In this study, the dynamic responses of a riser under the combined excitation of internal waves and background currents are studied. A modified Taylor-Goldstein equation is used to calculate the internal waves vertical structures when background currents exist. By imposing rigid-lid boundary condition, the equation is solved by Thompson-Haskell method. Based on the principle of virtual work, a nonlinear differential equation for riser motions is established combined with the modified Morison formula. Using Newmark-${\beta}$ method, the motion equation is solved in time domain. It is observed that the internal waves without currents exhibit dominated effect on dynamic response of a riser in the first two modes. With the effects of the background currents, the motion displacements of the riser will increase significantly in both cases that wave goes along and against the currents. This phenomenon is most obviously observed at the motions in the first mode.

Static Friction Compensation for Enhancing Motor Control Precision (모터 제어 정밀도 향상을 위한 정지 마찰력 보상)

  • Ryoo, Jung Rae;Doh, Tae-Yong
    • Journal of Institute of Control, Robotics and Systems
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    • v.20 no.2
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    • pp.180-185
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    • 2014
  • DC motor is a representative electric motor commonly utilized in various motion control fields. However, DC motor-based motion control systems suffer from degradation of position precision due to nonlinear static friction. In order to enhance control precision, friction model-based compensators have been introduced in previous researches, where friction models are identified and counter inputs are added to control inputs for cancelling out the identified friction forces. In this paper, a static friction compensator is proposed without use of a friction model. The proposed compensation algorithm utilizes internal state manipulation to generate compensation pulses, and related parameters are easily tuned experimentally. The proposed friction compensator is applied to a DC motor-based motion control system, and results are presented in comparison with those without a friction compensator.

A study on Motion Characteristics of VLCO by Draft (Simple floating body) (가변진동수주장치의 흘수변화에 따른 운동특성연구 (단일 부유체))

  • Lee, Seung-Chul;Bae, Sung-Yong
    • Journal of Power System Engineering
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    • v.18 no.5
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    • pp.16-21
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    • 2014
  • The structure of the variable liquid column oscillator(VLCO) is analogous to that of the tuned liquide column damper used to suppress oscillatory motion in large structures like tall buildings and cargo ships. VLCO is the technology to absorb high potential energy made by process of accelerated motions to occur the effect of an air spring by installation of inner air chamber. So, the application of VLCO can obtain to improve efficiency of energy than wave energy converters made in Pelamis Company. In this research, the experiments were carried out for the motion characteristics of simple floating body by varying the amount of internal fluid. The experimental results were compared with the calculated results.

Sloshing Flows in Ship Tanks

  • Kim, Yonghwan;Shin, Yung-Sup
    • Journal of Ship and Ocean Technology
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    • v.4 no.3
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    • pp.21-32
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    • 2000
  • In the present paper, the sloshing flow in the liquid holds of a large tanker is simulated using a numerical method. In the fluid domain, the three-dimensional Navier-Stokes equation with free surface is solved using a finite difference method, and the realistic shapes of multi holds are modeled including the internal members. The time-history of the tank motion is obtained using a time-domain program for ship motion. In order to computer the impulsive pressures on internal structures, a concept of buffer zone is adopted near the tank ceiling during impact occurrence. This study demonstrates that the global fluid motion in the multi liquid holds of ships and FPSO's can be simulated using the numerical method and the corresponding local pressure can be predicted with reasonable accuracy.

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