• ETRI Journal
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• 제26권4호
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• pp.292-296
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• 2004

In this paper we present a new current-mode electronically tunable universal filter using only plus-type current controlled conveyors (CCCII+s) and grounded capacitors. The proposed circuit can simultaneously realize lowpass, bandpass, and highpass filter functions - all at high impedance outputs. The realization of a notch response does not require additional active elements. The circuit enjoys an independent current control of parameters $\omega_0$ and $\omega_0/Q$. No element matching conditions are imposed. Both its active and passive sensitivities are low.

• ETRI Journal
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• 제31권3호
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• pp.298-303
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• 2009

A single-switch parallel resonant converter for induction heating is implemented. The circuit consists of an input LC-filter, a bridge rectifier, and a controlled power switch. The switch operates in soft commutation mode and serves as a high frequency generator. The output power is controlled via the switching frequency. A steady state analysis of the converter operation is presented. A closed-loop circuit model is also presented, and the experimental results are compared with the simulation results.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.247-250
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• 1998

In this paper, a special kind of timer-controlled network is analyzed. A timer-controlled network with an immediate response scheme is modeled and analyzed. It is assumed that each station on the network has single buffer and individual finite number of maximum retransmission limit. The physical meanings of derived results are briefly explained, which prove that the results completely coincide with the physical operations of that kind of network. It is also shown by computer simulations that derived analysis results are valid.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.680-683
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• 1999

A thyristor controlled shunt compensator, which is installed in the middle of the transmission line is adopted for controlling real power flow in a simple power transmission system. By means on the Fourier series representation of the thyristor switching action and the system parameters, the thyristor current equations are derived, which transmit the required real power of the simple power transmission system and inform the thyristor firing angle, the thyristor conduction angle, the power flows and the harmonic characteristics EMTP simulations at the various operating points show the dynamic characteristics of the thyristor controlled shunt compensator and correspond to the results calculated with the Fourier series representation.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.474-479
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• 2004

This paper presents an economical solution of the control system of robot, which is widely applied to sophisticated robots. The proposed control system is built on a foundation that is combined between driver motor, PC controlled servo-motor control card, and driver software. The solution had been applied to design hardware of controlled 6-DOF (Degree Of Freedom) robot. The controlled system is used to control VML Robot (Vehicle Mechatronic Lab). Addition, because of flexibility of the solution, the controller can be suit with widely robots at used servo-moto.

• KSBB Journal
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• 제5권4호
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• pp.377-382
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• 1990

The characteristics controlled drug release have been studied for biodegradable polymer matrix. Polymer matrix was prepared from glycerine, prednisolone and dextran. Mathematical analysis of the data showed that the release behavior actually conformed to the Higuchi's diffusion controlled model. The release time was increased as drug loading doses increased, whereas decreased as glycerine concentration increased. The release rate did not change by varying molecular weight of dextran.

• 전기의세계
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• 제23권6호
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• pp.56-59
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• 1974

It is well-known that the anode circuit of SCR has the current controlled negative resistance characteristic. Recently the present auther has shown that the gate circuit of SCR has the voltage controlled negative resistance characteristic for the constant anode voltage. It is shown of the equivalent model to SCR(when conducting) the voltage controlled negative resistance characteristic for gate circuit. And it is possible to make SCR gate oscillators with their desired characteristic for illustration.

• 대한전기학회논문지
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• 제36권2호
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• pp.107-113
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• 1987

A complete design of a new digital control circuit for a three-phase controlled rectifier is presented. The circuit consists of a gating signal generating ROM, down counter and adder. Proposed scheme is simple and quite adequate to the microprocessor-based digitally controlled systems. The basic principle and operation characteristics of the circuit are described and experimental-results show good dynamic performance. Synchronization problem with noisy reference is also discussed. The basic phylosophy developed can be extended to the other phase control system, e.g., cycloconverters, ac voltoge controllers, etc.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1540-1542
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• 2005

In SMPS, digital control techniques are adopted widely. But Digital controlled SMPS has poor performance of regulation and transient response than analog controlled SMPS. Delay time of control computing and low frequency of updating duty ratio make digital controlled SMPS poor performance. This paper proposed the optimized control computation to increase not only frequency of updating duty ratio but also switching frequency of SMPS.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제30권4호
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• pp.136-144
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• 2019

Early identification and intervention for autism spectrum disorder (ASD) were reported to be important for outcomes or clinical courses. However, there have been a few robust evidences for effectiveness of early intervention until now. This review aims to identify the effectiveness of early intervention by investigating the randomized controlled trial (RCT) of early intervention for autism. There are some RCT studies using behavioral program. Although there are some significant findings, the outcome measurements and small sample size are the limitations. Further studies are needed.