• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.5
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• pp.316-322
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• 2005

In order to develop a floating breakwater, which can efficiently control long period waves, vertical plates are attached in pontoon. Wave control and dynamic behaviors of the newly developed vertical plates type are verified from numerical analysis and hydraulic experiment. As a result, for the wave control and energy dissipation, the newly developed vertical plates type is more efficient than the conventional pontoon type. For the floating body motion, the wave transmission, depending on incident wave period, is decreased at the natural frequency. Dimensionless drift distance has similar trend of the reflection rate of wave transformation near natural frequency except maximum and minimum values. Dimensionless maximum tension is 17 percent of the weight of floating breakwater in case of the conventional pontoon type and 18 percent or 14 percent in case of the newly developed vertical plates type. Thus, it is shown that the wave control is improved by the vertical plates type. In addition, by adjusting the interval of the front and back vertical plate, we would control proper wave control.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.11
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• pp.937-943
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• 2016

Vertical velocity is critical in many areas, such as the control of unmanned aerial vehicles, fall detection, and virtual reality. Conventionally, the integration of GPS (Global Positioning System) with an IMU (Inertial Measurement Unit) was popular for the estimation of vertical components. However, GPS cannot work well indoors and, more importantly, has low accuracy in the vertical direction. In order to overcome these issues, IMU-barometer integration has been suggested instead of IMU-GPS integration. This paper proposes a new complementary filter for the estimation of vertical velocity based on IMU-barometer integration. The proposed complementary filter is designed to minimize drift error in the estimated velocity by adding PID control in addition to a zero velocity update technique.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.30-35
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• 1990

Learning control of a robot manipulator is proposed using the backpropagation neural network. The learning controller is composed of both a linear feedback controller and a neural network-based feedforward controller. The stability analysis of the learning controller is presented. Three energy functions are selected in teaching the neural network controller : 1/2.SIGMA.vertical bar torque error vertical bar $^{2}$, 1/2.SIGMA..alpha. vertical bar position error vertical bar $^{2}$ + .betha. vertical bar velocity error vertical bar $^{2}$ + .gamma. vertical bar acceleration error vertical bar $^{2}$ and learning methods are presented. Simulation results show that the learning controller which is learned to minimize the third energy function performs better than the others in tracking problems. Some properties of the learning controller are discussed with simulation results.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.289-291
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• 1996

Linear induction motor(LIM) is widely used to drive magnetic levitation train. To drive LIM, different control method compared with conventional rotary type machine is needed. Since vertical force is generated inherently and it effects on the levitation system, vertical force should be kept constant for stable levitation. To keep vertical force constant, slip frequency should be kept constant. Once slip frequency is kept constant, tractive force can be controlled by adjusting motor currents. In this paper, control methods used so far arc analyzed with some experimental results and decoupling control algorithm is proposed to control tractive and vertical force separately. Control algorithm is verified through simulation.

• International Journal of Aeronautical and Space Sciences
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• v.15 no.3
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• pp.293-301
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• 2014

We present a study of vertical dynamics control of an electrostatically levitated gyro-accelerometer considering the wobbling effect and propose a tilt stabilization method with newly introduced control electrodes. Typically, a rotor in a vacuum rotates at high velocity, which may create a drift rate and lead to displacement instability due to the tilt angle of the rotor. To analyze this, first we set up a vertical dynamic equation and determined simulation results regarding displacement control. After deriving an equation for drift dynamics, we analyzed the drift rate of the rotor and the wobbling effect for displacement control quantitatively. Then, we designed new sub-electrodes for moment control that will decrease the drift amplitude of wobbling dynamics. Finally, a simulation study demonstrated that the vertical displacement control with the wobbling compensation electrodes mitigated the rotor's drift rate, showing the effectiveness of the newly proposed control electrodes.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.9 s.180
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• pp.2371-2380
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• 2000

In this paper, we developed the proximity exposure system with the vertical structure of glass and mask stage to minimize the mask's warp caused by the pull of gravity. This system, which canirradiate the ultra violet through 1440 H 850 $\textrm{mm}^2$ and 1330X 1015 $\textrm{mm}^2$ exposure area, has the followingcharacteristics. The glass stage can be inclined by 80 degrees at vertical structure to load substrate withsafety on it. When the glass stage is the vertical state, the gap control, alignment control and exposureof ultra violet are executed. So, it enhances the pattern uniformity by minimizing the mask's warp. Theglass stage can also control the gap between the mask and the substrate by the coarse and fine motioncontrol. The mask stage can adjust the posture of photomask to the position of substrate by imageprecessing method. The galss stage for the gap control and the mask stage for the alignment aredesigned independently for each function.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.1242-1247
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• 2011

This study investigates vertical vibration control method for railway structure by using vertical vibration control device. The device consists of high stiffness polyurethane spring and friction damper recognized by National Center for Earthquake Engineering Research of USA for durability. To confirm the capacity of vertical vibration control, at first, behavior equation is established by considering correlation among the components. Then, hysteresis curve is drawed from behavior equation. By considering both dynamic behaviors and material nonlinearities, more reasonable behavior of the device can be simulated. After that, the Validity of the vibration control trend is proved by FEM(Finite Element Method).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.5
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• pp.2033-2040
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• 2013

There have been noticeable developments for the optimization of the highway and railroad alignments with the IT and computerized tools. The designers expect that all of the quantitative design elements should be considered. This study developed a methodology which can be useful for the vertical alignment design. It provides a accurate "vertical control point" searching method, and makes the vertical alignment optimization more efficiently. The vector method makes the searching faster and calculates more accurate application sections. The results from this method generate more reliable vertical alignments than the conventional raster method for less computation time.

• Journal of the Korean housing association
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• v.23 no.5
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• pp.51-60
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• 2012

Large-scale urban developments with increasing population and expansion of industrial facilities have destroyed the ecosystem. Consequently, the importance of vertical farm as a form of urban agriculture is increasing. However, such problems of vertical farms as economy and lack of awareness of residents are being raised. Firstly, this study derived types of vertical farm that are applicable to residential spaces through an examination of vertical farm buildings, and then inferred assessment items for a questionnaire survey for the development of u-services. Secondly, based on the issues deduced from the survey, u-services needed in vertical farm buildings were derived to use them as the basic data when we plan for a ubiquitous vertical farm building in residential space in the future. As result, the following uservices of ubiquitous vertical farm were proposed: u-notification service about the condition of crops from the aspect of growth management based on ubiquitous technology, remote/automatic control u-services, harvest information u-service for harvest management, recipe information u-service, and indoor air quality monitoring u-service, indoor environment adjusting u-service, and farm environment control u-service. Considering that many new buildings in Korea are residential buildings and many high-rise buildings are being planned, studies on vertical farm buildings must be continued.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.161-164
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• 2008

A realization for EMG signal sensing and vertical control system of robotizing arm is presented in this paper. The system is realized that a fine EMG bio-signals of humans' arm muscle are detected by surface electrode sensor, making a high performance amplifier and filtering, converting analog into digital signal and driving a servomotor for robotizing arm. The system is experimented by monitoring multiple step vertical control angles of robotizing arm corresponding to EMG signals in moving arm muscles. The experimental result are that the vertical control level is measured to around 2 degrees and mean error is 5% approximately.