• Journal of the Korean Society for Precision Engineering
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• v.30 no.5
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• pp.529-536
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• 2013

Most serious stroke patients have the paralysis on their wrists, and can't use their hands freely. But their wrists can be recovered by rehabilitation exercises. Recently, professional rehabilitation therapeutists help stroke patients exercise their wrists in hospital. But it is difficult for them to rehabilitate their wrists, because the therapeutists are much less than stroke patients in number. Therefore, the wrist twist-exercise rehabilitation robot that can measure the twist force of the patients' wrists is needed and developed. In this paper, the six-axis force/moment sensor was designed appropriately for the robot. As a test result, the interference error of the six-axis force/moment sensor was less than 0.85%. It is thought that the sensor can be used to measure the wrist twist force of the patient.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.1
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• pp.49-56
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• 2003

The hydrodynamic interference between two circular cylinders in tandem and side by side arrangements was investigated by measuring of lift and drag on each cylinder. The time variations of interference lift and drag coefficients in each arrangement were observed at center-to-center pitch ratios of P/D=1.25 and 2.5 and Reynolds number of $Re=1.5\times10^4$. Average interference lift and drag coefficients were also observed at pitch ratios from P/D=1.25 to 2.5 and Reynolds number from $Re=1.5\times10^4$ to $1.5\times10^4$. The hydrodynamic interference between two circular cylinders differed with the shape of the arrangement and the pitch ratio, but the characteristics were revealed by measuring of lift and drag on each cylinder.

• Wind and Structures
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• v.8 no.3
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• pp.147-161
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• 2005

Two identical tall building models with square cross-sections are experimentally studied in a wind tunnel with high-frequency-force-balance (HFFB) technique to investigate the interference effects on wind loads and dynamic responses of the interfered building. Another wind tunnel test, in which the interfered model is an aeroelastic one, is also carried out to further study the interference effects. The results from the two kinds of tests are compared with each other. Then the influences of turbulence in oncoming wind on dynamic interference factors are analyzed. At last the artificial neural networks method is used to deal with the experimental data and the along-wind and across-wind dynamic interference factor $IF_{dx}$ & $IF_{dy}$ contour maps are obtained, which could be used as references for wind load codes of buildings.

• International Journal of Precision Engineering and Manufacturing
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• v.5 no.3
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• pp.54-61
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• 2004

This paper describes the development of a 6-axis robot's finger force/moment sensor, which measures forces $F_x$(x-direction force), $F_y$and $F_z$, and moments $M_x$ (x-direction moment), $M_y$ and $M_z$ simultaneously, for stable grasping of an unknown object. In order to safely grasp an unknown object using the robot's gripper, the force in the gripping direction and the force in the gravity direction should be measured, and the force control should be performed using the measured forces. Also, the moments $M_x$, $M_y$ and $M_z$ to accurately perceive the position of the object in the grippers should be detected. Thus, the robot's gripper should be composed of 6-axis robot's finger force/moment sensor that can measure forces $F_x$, $F_y$ and $F_z$, and moments $M_x$ $M_y$ and $M_z$ simultaneously. In this paper, the 6-axis robot's finger force/moment sensor for measuring forces $F_x$, $F_y$ and $F_z$, and moments $M_x$ $M_y$ and $M_z$ simultaneously was newly modeled using several parallel-plate beams, designed, and fabricated. The characteristic test of the fabricated sensor was performed, and the result shows that interference errors of the developed sensor are less than 3%. Also, Robot's gripper with the 6-axis robot's finger force/moment sensor for the characteristic test of force control was manufactured, and the characteristic test for grasping an unknown object using the sensors was performed using it. The fabricated gripper could grasp an unknown object stably. Thus, the developed 6-axis robot's finger force/moment sensor can be used for robot's gripper.

• Tribology and Lubricants
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• v.9 no.1
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• pp.32-37
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• 1993

The equations are derived for the evaluation of the axial contact forces. The contact forces of rubber seals are analyzed as a function of the ratio of real contact length, the thickness of seal lip, the inclined angle of seal lip, and the interference between the edge of seal lip and the rotating inner ring. The experimental apparatus is developed for the test of seal lip contact force. The data for designing rubber seals are presented in terms of the ratio of real contact length, initial inclined lip angle, lip thickness. and the interference. The results obtained from the derived equation for the contact force are in good agreement with the experimental results.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.6
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• pp.1559-1566
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• 1994

Using the finite element method, the contact force, contact band width and temperature distribution of lip seals analyzed for the interference including some nonlinearities such as material nonlinearity, geometrical nonlinearity and nonlinear contact boundary condition. The calculated results showed that the contact stress concentrated on the contact zone between the garter spring and the rubber toward the flex side, the contact edge of lip seals. The high contact forces due to the increased interference separate the sealing gap between the lip edge and the rotating shaft. This may lead to leak the sealed oil.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1013-1014
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• 2010

• Wind and Structures
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• v.29 no.4
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• pp.279-297
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• 2019

Strong winds threaten the safety of vehicles on long-span bridges considerably, which could force traffic authorities to reduce speed limits or even close these bridges to traffic. In order to maintain the safe and economic operation of a bridge, a reasonable evaluation of the driving safety on that bridge is needed. This paper aims at carrying outdriving safety analyses for three types of vehicles on a long-span bridge in crosswinds by considering the aerodynamic interference between the bridge and the vehicles based on the wind-vehicle-bridge coupling vibration analysis. Firstly, CFD numerical simulations along with previously obtained wind tunnel testing results were used to determine the aerodynamic force coefficients of the three types of vehicles on the bridge. Secondly, the dynamic responses of the bridge and the vehicles under crosswinds were simulated, and based on those, the driving safety analyses for the three types of vehicles on the bridge were carried out for both cases considering and not considering the aerodynamic interference between the vehicles and the bridge. Finally, the effect of the aerodynamic interference on the safety of the vehicles was investigated. The results show that the aerodynamic interference between the bridge and the vehicles not only affectsthe accident critical wind speed but also the accident type for all three types of vehicles. Such effects are also different for each of the three types of vehicles being studied.

• The Journal of the Korean dental association
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• v.53 no.6
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• pp.402-410
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• 2015

The aims of occlusal adjustment are as follows: to eliminate occlusal interference, to redirect force generated during function to which is favorable for teeth, to improve mastication efficiency and simultaneously establish stable maximal intercuspation or centric occlusion. Also, it should permit mandible to move freely from all positions. The sequence of occlusal adjustment in natural teeth and fixed prosthesis shall be as follows: 1) Eliminate interference that prevent optimal intercuspation and recontouring adjustment 2) Establish maximal intercuspation 3) Eliminate interference in lateral mandibular movement 4) Eliminate interference in anterior mandibular movement 5) Refine occlusal relationships.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.349-350
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• 2010