• 한국수산과학회지
• /
• 제38권5호
• /
• pp.316-322
• /
• 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.

• 제어로봇시스템학회논문지
• /
• 제22권11호
• /
• pp.937-943
• /
• 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
• /
• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 26-27 Oct. 1990
• /
• pp.30-35
• /
• 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.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1996년도 하계학술대회 논문집 A
• /
• pp.289-291
• /
• 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
• /
• 제15권3호
• /
• pp.293-301
• /
• 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.

• 대한기계학회논문집A
• /
• 제24권9호
• /
• pp.2371-2380
• /
• 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.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2011년도 춘계학술대회 논문집
• /
• pp.1242-1247
• /
• 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).

• 대한토목학회논문집
• /
• 제33권5호
• /
• pp.2033-2040
• /
• 2013

선형 설계 시 고려해야 할 수많은 정량적 또는 정성적인 인자들에 대하여 최신 IT기술을 접목하고 컴퓨터의 빠른 연산기능을 이용하여 단시간에 좀 더 많은 선형을 검토할 수 있는 선형 최적화 기술은 그동안 주목할 만 한 발전을 이루어 왔다. 특히 선형 최적화시 정량적인 설계요소의 정확한 반영과 수준 높은 성과품 출력에 대한 사용자의 요구는 설계기술자의 수준을 요구하는 단계에 이르렀다. 이런 요구사항에 부응하여 본 연구는 종단선형 최적화시 기존의 방식을 탈피한 보다 정밀한 Vertical Control Point(VCP) 적용구간을 탐색하고 설계에 적용할 수 있는 방안을 마련하였다. 이는 벡터방식을 이용한 VCP처리 기법으로 빠른 탐색 과 정확한 적용구간을 계산해 냄으로서 종전 래스터방식 결과와 비교해 보았을 때 보다 신뢰할 수 있는 종단선형을 도출할 수 있게 되었다. 특히 래스터 방식에 비해 벡터방식을 적용 할 경우 정밀도가 향상 되리라는 것은 주지의 사실이나, 선형최적화 기술의 선결조건인 처리속도를 저하시키지 않고 벡터방식을 적용 하였다는 것이 본 연구의 성과라고 할 수 있다.

• 한국주거학회논문집
• /
• 제23권5호
• /
• pp.51-60
• /
• 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.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2008년도 추계종합학술대회 B
• /
• pp.161-164
• /
• 2008

본 논문은 근전도 신호를 검출하고 로봇팔의 수직제어시스템을 구현하기 위한 연구이다. EMG 신호는 사람의 팔 근육에 흐르는 미세한 생체신호가 표면전극센서에 의해서 사용하여 검출되고 고성능 증폭, 필터링, ADC과 로봇팔의 서보 모터 구동 시스템으로 구현된다. 실험은 팔근육 움직임에 따른 EMG신호와 로봇팔의 다단계 수직제어 각도를 모니터링 한다. 시스템의 실험결과 수직제어각도는 2도 정도이며 평균오차는 5%이다.