• Proceedings of the Computational Structural Engineering Institute Conference
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• 1995.10a
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• pp.242-249
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• 1995

In order to search more efficient structural control algorithm, several closed-loop algorithm are developed. Among those, feedback control algorithm using parameters as displacement velocity, and acceleration has been studied. In this paper, especially the characteristics of accleration feedback is studied as more efficient control algorithm than any others. Furthermore the fact that ATMD with acceleration feedback system further reduce the variance of structural displacement rather than with displacement or velocity feedback system will be examined and proved.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.10a
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• pp.275-282
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• 1999

In this study, the algorithm which can estimate displacements from the acceleration data is developed. For proving the validity of this study, the calculated displacements are compared with the measured displacements through the forced vibration tests in the laboratory. So the sampling frequency and filtering range for the estimation of the displacements are proposed. Finally, these results are applied to estimate displacements from the acceleration data obtained from the real bridge.

• Proceedings of the KSR Conference
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• 2002.10b
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• pp.892-897
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• 2002

The research was requested by Meridian Rail Corporation in United States. The Swing Motion Bogie can application by Korea style if synthesize study result of bogie strength evaluation, bogie dynamic characteristics analysis, actual test(maximum speed, derailment coefficient, lateral force, vertical force, vibration acceleration, steady state lateral acceleration) etc..

• Journal of Industrial Technology
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• v.20 no.B
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• pp.175-182
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• 2000

In this paper, a novel speed control strategy using an acceleration feedforward compensation by the estimation of the system inertia is proposed. With the proposed method, the enhanced speed control performance can be achieved and the speed response against the disturbance torque can be improved for the vector-controller induction motor drive systems in which the bandwidth of the speed controller cannot be made large enough. The experimental results confirm the validity of the proposed strategy.

• Proceedings of the KIEE Conference
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• 2004.05a
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• pp.41-43
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• 2004

This paper is concerned with attitude estimation using low cost, small-sized accelerometers and gyroscopes. A two step extended Kalman filter is proposed, which adaptively compensates external acceleration. External acceleration is the main source of estimation error. In the proposed filter, direction of external acceleration is estimated. According to the estimated direction, the accelerometer measurement covariance matrix of the two step extended Kalman filter is adjusted. The proposed algorithm is verified through experiments.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.1
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• pp.147-153
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• 2001

This paper proposes a shaker system design for acceleration test of gimbal. Main reason of shaker system design is to give acceleration to the gimbal, which is moving and tracking the target on the tracking test equipment. The shaker system is mounted on the tracking test equipment. It uses the scotch yoke mechanism to have the constant movement in return. The Scotch yoke mechanism changes the rotational movement of constant velocity to simple harmonic motion.

• Nuclear Engineering and Technology
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• v.34 no.4
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• pp.314-322
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• 2002

A new extrapolation method is developed and applied to the additive angular dependent rebalance (AADR) acceleration for discrete ordinates neutron transport calculations. With this extrapolation, the convergence of AADR solution for distinct discretizations between the high- order and low-order equations is remarkably improved and thus the “inconsistent discretization problem” is resolved. Fourier analysis is also performed to find the optimal extrapolation and weighting parameters, which give the smallest spectral radius. The numerical tests demonstrate that the AADR with extrapolation works well as predicted by the Fourier analysis.

• Advances in materials Research
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• v.2 no.4
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• pp.195-208
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• 2013

A comprehensive theory of the spin coating technique has been reviewed and the basic principles and parameters controlling the process are clearly highlighted, which include spin speed, spin time, acceleration and fume exhaust. The process generally involves four stages: a dispense stage, substrate acceleration stage, a stage of substrate spinning at a constant rate and fluid viscous forces dominate fluid thinning behaviour and a stage of substrate spinning at a constant rate and solvent evaporation dominates the coating thinning behaviour. The study also considered some common thin film defects associated with this technique, which include comet, striation, chucks marks environmental sensitivity and edge effect and possible remedies.

• Structural Engineering and Mechanics
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• v.52 no.2
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• pp.275-290
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• 2014

In this paper, Simple Adaptive Control (SAC) method is used to mitigate the detrimental effects of earthquakes on MR-damper equipped structures. Acceleration Feedback (AF) is utilized since measuring the acceleration response of structures is known to be reliable and inexpensive. The SAC is simple, fast and as an adaptive control scheme, is immune against the effects of plant and environmental uncertainties. In the present study, in order to translate the desired control force into an applicable MR damper command voltage, a neural network inverse model is trained, validated and used through the simulations. The effectiveness of the proposed AF-based SAC control system is compared with optimal H2/LQG controllers through numerical investigation of a three-story model building. The results indicate that the SAC controller is substantially effective and reliable in both undamaged and damaged structural states, specifically in reducing acceleration responses of seismically excited buildings.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.9
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• pp.761-767
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• 2005

There exists a structural limit of 2WS cars that drivers would not like simultaneously to follow the desired path and attenuate moments resulting from disturbances because lateral acceleration and yaw rate are coupled inherently. In order to overcome the limit, the 4WS cars that have rear wheel steering as an additional input have been introduced. But the 4WS cars have disadvantages that much cost is required due to structural alteration, it is difficult to be used to the driving circumstances and tire performances are not efficient in nonlinear or large lateral acceleration ranges. Therefore, it is proposed that, in this paper, a robust controller is easy to apply to 2WS cars by using direct yaw moment, decouples lateral acceleration from yaw motion and is robust against disturbances and uncertainties of system parameters, and thus the proposed control method has the advantages of 4WS cars which can be achieved in 2WS cars.