• 아동학회지
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• 제34권1호
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• pp.1-20
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• 2013

This study examined the emergent literacy development of children and the effects of the home literacy environment on it. 861 pairs each-consisting of a mother and a child aged from three to six years old were asked to complete the early literacy parent questionnaire (Boudreau, 2005) and the home literacy environment questionnaire (Park & Kim, 2008). The results showed that : (1) girls achieved higher scores than boys in emergent literacy and its subcategories. (2) there were age differences in all of the subcategories of emergent literacy except the categories of 'orientation toward literacy' and 'phonological awareness'. (3) The study revealed that 'reading books' in the home literacy environment was the most contributive variable in predicting emergent literacy after controlling the age and gender followed by 'literacy learning'

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 춘계학술대회
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• pp.433-434
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• 2018

4차 산업기술과 농업을 접목한 스마트팜 기술은 고령화와 인구감소로 인해 악화되어 가고 있는 우리나라의 농업을 일으켜줄 해결책으로 기대되고 있다. 이에 따른 스마트팜 기술개발이 중요시 여겨지고 있으며 기술개발의 토대가 될 데이터베이스에 대해서 설계하고 C#환경에서 데이터들을 접근 제어하는 방법에 대해서 기술하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 1999년도 추계학술대회논문집
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• pp.273-280
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• 1999

Yard cranes are very useful equipments for handing of heavy containers, But rope-driven yard cranes must have a little of sway and skew motion because ropes are passive mechanical device. Therefore rope-driven yard cranes require skilled drivers to depress sway and skew motions. So many researches have been concentrated on anti-sway and anti-skew algorithm controlling trolley speed or rope tension. Although many efforts, the rope-driven method is not proper to an automated yard equipment because of sway and skew motion. This paper will propose a new concept yard crane which has a new structure, overcomes defects of rope-driven cranes and is proper to automation. And we will study its actuality

• Smart Structures and Systems
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• 제5권1호
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• pp.55-68
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• 2009

In the present study, active control of a smart beam under forced vibration is analyzed. The aluminum smart beam is composed of two piezoelectric patches and strain gauge. One of the piezoelectric patches is used as controlling actuator while the other piezoelectric patch is used as vibration generating shaker. The smart beam is harmonically excited by the piezoelectric shaker at its fundamental frequency. The strain gauge is utilized to sense the vibration level. Active vibration reduction under harmonic excitation is achieved using both strain and displacement feedback control. Control actions, the finite element (FE) modeling and analyses are directly carried out by using ANSYS parametric design language (APDL). Experimental applications are performed with LabVIEW. Dynamic behavior at the tip of the beam is evaluated for the uncontrolled and controlled responses. The simulation and experimental results are compared. Good agreement is observed between simulation and experimental results under harmonic excitation.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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• pp.236-239
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• 2003

In this paper, we investigate the issues for the design and implementation of tele-operation system based on the haptic interface. Here, the 3-DOF haptic device and the x-y-z stage are employed as master controller and slave system respectively. In this master-slave system, the force feedback algorithm, the modeling of virtual environments and the control method of x-y-z stage are proposed. In this paper, inernet network is used for data communication between master and slave. We construct virtual environment of the real convex surface from the force-feedback in controlling the X-Y-Z stage and getting the force applied by the 3-DOF haptic device.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 추계학술대회 논문집
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• pp.291-295
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• 2009

Economic and environmental concerns over fossil fuels encourage the development of photovoltaic(PV) energy systems. Due to the intermittent nature of solar energy. energy storage is needed in a stand-alone PV system for the purpose of ensuring continuous power flow. Grid-connected PV system that supply power in a critical load demand require to curb power fluctuation. In this case. SCB is a effectiveness in controlling power variation due to intrinsic PV system. We propose the Matlab/Simulink dynamic model and power flow characteristics of a hybrid energy system with PV and SCB.

• 대한전기학회논문지:시스템및제어부문D
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• 제53권11호
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• pp.753-759
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• 2004

This paper presents a modeling and simulation of a fuzzy controller for maximum power extraction of a grid-connected wind energy conversion system with a link of a rectifier and an inverter. It discusses the maximum power control algorithm for a wind turbine and proposes, in a graphical form, the relationships of wind turbine output, rotor speed, power coefficient, tip-speed ratio with wind speed when the wind turbine is operated under the maximum power control. The control objective is to always extract maximum power from wind and transfer the power to the utility by controlling both the pitch angle of the wind turbine blades and the inverter firing angle. Pitch control method is mechanically complicated, but the control performance is better than that of the stall regulation method. The simulation results performed on MATLAB will show the variation of generator's rotor angle and rotor speed, pitch angle, and generator output.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.129-133
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• 2005

In this paper, first the thermodynamic model is presented to one of the super heaters and sprays of the Nekka power plant and then its unknown parameters are identified according to the registered data of the power plant. SCO control method is introduced to control the external steam temperature of super heater. Finally the conventional method in power plant for controlling external steam temperature of super heater is compared with new method and their performances are presented..

• 대한전자공학회논문지
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• 제25권8호
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• pp.916-926
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• 1988

In this paper, we explore real-time implementation of various dynamic control algorithms, which use the different levels of the information of the dynamics, using a SCARA type robot to show the feasibility and effectiveness of such algorithms. For these purposes, the kinematics of the SCARA type robot is anayzed and the manipulator-actuator dynamic equations based on Lagrange mechanisms are derived. Experimental results indicate that computed torque technique and iterative learning control methods perform better than classical PID control and that these algorithms can be effectively applied to controlling industrial manipulators.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.78.3-78
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• 2002

In this paper, we present a five-DOF actuator based on dielectric elastomer. The actuator is designed for generating five DOFs motions to drive a micro camera steering module and provides all the functions for controlling CCD array such as focusing, pan and tilting. Basic modeling of the actuator is performed, and simulation works and experimental verifications are conducted, too. The camera steering module includes most parts necessary for driving the actuator such as a micro-controller and DC-DC converter, etc. It can be operated with a personal computer using only communication lines without external power supply. A prototype is developed and its performance is experimentally proved. $\textbullet$ artificial muscle, EAP, actuator.