• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.71-76
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• 2008

This paper is concerned with the active vibration control of elevator by means of the active roller guide. To this end, a dynamic model for the horizontal vibration of the elevator consisting of a supporting frame, cage and active roller guides was derived using the energy method. Free vibration analysis was then carried out based on the equations of motion. Active vibration controller was designed based on the equations of motion using the LQR theory and applied to the numerical model. Rail irregularity and wind pressure variation were considered as external disturbance in the numerical simulations. The numerical results show that the active vibration control of elevator is possible.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.993-998
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• 1992

The paper treated the oscillation control of cargo rope and the position control of cart for a tower crane system by adopting the optimal regulator method. Since the tower crane has nonlinearity and it is very unstable when the cargo is mobiling, an insensitive control system with respect to oscillation of cargo rope and disturbance such as wind is required. In this paper, model equation of the tower crane is induced by using Lagrange equation and it is linearized at equilibrium point. The real time control of tower crane syste is implemented by 16bits microcomputer with A/D and D/A convetters to illustrate the application of the adopted optimal desgn method.

• 혜화의학회지
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• 제17권1호
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• pp.129-136
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• 2008

This study was performed to investigate the cause, symptom, treatment of carpal tunnel syndrome through Western medicine and Dong-Eui-Bo-Kham(東醫寶鑑). Results & conclusions 1. Carpal tunnel syndrome is a common peripheral nerve entrapment syndrome that is characterixed by pain, numbness, sensory disturbance along the dsitribution of the meridian nerve in hand 2. Treatment of carpal tunnel syndrome have included wrist immobilization, anti-inflammatory drug, local injection of steroid, nerve block and surgical decompression. 3. Carpal tunnel syndrome seems to be similar with numbness(痺證). The causes were usually pathogenic Wind, Cold, Dampness. 4．Acupuncture, herbal medicine, herbal acupuncture were used for treatment of carpal tunnel syndrome. We considered that more study to find various and effective methods oriental medicine for carpal tunnel syndrome should be made.

• 대한전기학회논문지:전력기술부문A
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• 제48권4호
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• pp.434-443
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• 1999

In this paper, neural network predictive PID (NNPPID) control system is proposed to reduce the vibration of building structure. NNPPID control system is made up predictor, controller, and self-tuner to yield the parameters of controller. The neural networks predictor forecasts the future output based on present input and output of building structure. The controller is PID type whose parameters are yielded by neural networks self-tuning algorithm. Computer simulations show displacements of single and multi-story structure applied to NNPPID system about disturbance loads-wind forces and earthquakes.

• 대한전기학회논문지:시스템및제어부문D
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• 제50권1호
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• pp.31-37
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• 2001

A robust adaptive technique for the longitudinal control of a platoon of automated vehicles is presented. A nonlinear model is used to represent the dynamics of each vehicle within the platoon. The external disturbances such as wind gust and a disturbance term due to engine transmission variations and so on are considered. The state observer is used to avoid direct measurement of the relative velocity or acceleration between the controlled and leading vehicles or the controlled vehicles's acceleration. The proposed controller guarantees to recover platoon stability in operation even if a speed dependent spacing policy is adopted, which incorporates a constant time headway in addition to the constant distance. It is shown that the proposed observer is exponentially stable, and the at the robust adaptive controller is stable. The simulation results demonstrate excellent tracking even in the presence of disturbances.

• 한국항해항만학회지
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• 제31권7호
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• pp.563-568
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• 2007

In this paper, an adaptive neural network controller and its application to automatic berthing control of ship is presented. The neural network controller is trained online using adaptive interaction technique without any teaching data and off-line training phase. Firstly, the neural networks used to control rudder and propeller during automatic berthing process are presented. Secondly, computer simulations of automatic ship berthing are carried out in Pusan bay to verify the proposed controller under the influence of wind disturbance and measurement noise. The results of simulation show good performance of the developed berthing control system.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 춘계학술대회 및 창립 30주년 심포지엄(논문집)
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• pp.67-74
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• 2006

In this paper, an adaptive neural network controller and its application to automatic berthing control of ship is presented. The neural network controller is trained online using adaptive interaction technique without any teaching data and off-line training phase. Firstly, the neural networks used to control rudder and propeller during automatic berthing process are presented. Finally, computer simulations of automatic ship berthing are carried out to verify the proposed controller with and without the influence of wind disturbance and measurement noise.

• 한국정밀공학회지
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• 제26권9호
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• pp.103-111
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• 2009

Multi-climbing hydraulic robots are used to lift construction factory (CF) synchronously for applications in the automation of a high-rise building construction. In this study, synchronous motion controller is proposed for the hydraulic robots, whose strategy is not only to make each robot follow the reference path basically by sliding-mode control, but also to synchronize motions of two adjacent cent robots consecutively by cross-coupled control technique. Simulations are performed by using SIMULINK for a system similar to a practical application that includes unbalance in CF and wind disturbance. The results show that the proposed controller significantly reduces synchronous errors, compared to the individual controller for each hydraulic robot.

• 천문학회보
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• 제44권1호
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• pp.50.3-50.3
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• 2019

The EUV wave is a disturbance that has been believed to be the fast-mode (shock) wave, which can propagate passing through magnetic field lines. After the passage of EUV waves, coronal streamers start to show kink-mode oscillations, and the footpoints, i.e., magnetic separatrices, of the oscillating streamers are observed as the so-called stationary front. We compare the stationary front observed by EUV imagers and coronal streamers observed in coronagraphic images. We analyze the successive events occurred in September 2011. We find that the stationary fronts are consistent with the coronal streamer boundaries, and they are located along the boundaries of coronal holes and active regions. Our results confirm that EUV waves are in fact fast-mode waves and demonstrate that the stationary front is a promising tool to probe into the source of slow solar wind that is the boundary of coronal streamers on the solar surface.

• Ocean and Polar Research
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• 제41권4호
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• pp.311-318
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• 2019

We analyzed the preliminary survey data (2014-2016) of macrobenthic community biomass (n = 112) from the wind farm area located in the southern part of the west coast of Korea and compared this data with data from the entire west coast (n = 369; 2006-2008). Modal classes from frequency distributions were 6 times higher in the latter (5 vs. 32 g/㎡). The mean and median values of the latter were 1.3 and 1.7 times higher (mean, 20.7 vs. 27.8 g/㎡; median, 17.1 vs. 29.5 g/㎡), and the maximum value was 3.4 times higher. Mood's median test showed significant difference at p-value = 0.01. We estimated the biomass-to-depth relationships from each data set by using Akaike Information Criterion and regarded the non-overlap of the 95% confidence intervals as indicating significant difference. The biomass was different from a 10 m depth below, and 3 times higher in the west coast at around 20 m compared with the maximum depth of the wind farm area. A local event of catastrophic sedimentation ranging from 1 to 2 m was observed in the wind farm during winter surveys. This could be a probable source of the lower biomass, but information on biomass seasonality and a natural experimental approach seem to be needed for the conduct of further studies. This study is meaningful in that it provided the background to assess future changes by understanding the lower level of benthic productivity in the area. We expect this study will contribute to the preparation of measures that can remove or mitigate the source of the lower biomass and improve the productivity of fishery resources in the area.