• Korean Journal of Child Studies
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• v.23 no.1
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• pp.87-104
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• 2002

This study investigated developmental levels and explored play behaviors in 194 4- and 5-year-old children from low-income families attending 18 daycare centers in Seoul. The Developmental Test for Korean Kindergartners(Korea Institute Curriculum & Evaluation, 1996) was used to assess developmental levels in seven areas. Play behaviors were observed during free-play in their classrooms. Data were analyzed by two-way ANOVA and $x^2$. Results were that the children from low-income families showed highest scores in motor skill development and the lowest scores in mathematical and scientific development. The children engaged most frequently in group-functional play, followed by onlooker behaviors, group-dramatic, and group-constructive play. Onlooker behaviors were the most frequent activity of the 4-year-olds, and the block corner was the most frequently used area during free-play.

• Journal of Dental Anesthesia and Pain Medicine
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• v.18 no.4
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• pp.261-265
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• 2018

Rett syndrome (RS) is a neurodevelopmental disorder characterized by loss of cognitive, motor, and social skills, epilepsy, autistic behavior, abnormal airway patterns, gastroesophageal reflux, nutritional problems, and severe scoliosis. Although girls with RS show normal or near-normal growth until 6-8 months, they lose their skills after that. The anesthetic management of these patients requires care because of all these clinical features. Especially in the postoperative period, prolonged apnea is common and extubation is delayed. In this case report, the effect of using sugammadex was presented in a 16-year-old girl with RS. The patient's all bimaxillary teeth and 4 wisdom teeth were extracted under general anesthesia in one session with minimal surgical trauma and moderate bleeding. Sugammadex can be a rapid and reliable agent for the reversal of the neuromuscular block in neurodegenerative patients.

• International Journal of Safety
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• v.7 no.1
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• pp.1-4
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• 2008

Application of the Microsoft robotics studio (MSRS) to the design of a factory safety monitoring robot is presented. Basic structures of the MSRS and the service are introduced. The service is the key building block of the MSRS. Control of the safety monitoring robot is performed using four basic services: 1) the robot service which communicates with the embedded micro-processor and other services, 2) the sensor service that notifies the subscribing services of the change of the sensor value, 3) the motor service which controls the power levels to the motors, 4) the drive service which maneuvers the robot. With built-in capabilities of the MSRS, control of factory safety monitoring robot can be more easily performed.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.233-233
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• 2000

Direct torque control (DTC) scheme provides a very quick torque response without the complex field-orientation block and inner current regulation loop. DTC is known as an appropriate scheme for high power induction motet drives because it can be used at lower switching frequency. There are two major drawbacks with the application of DTC schemes : one is large current harmonics due to flux drooping in a low speed range, the other is that the inverter switching frequency is varying according to motor parameters and operating speed. Switching devices in the power electronics drives should be supported for relatively high switching frequency. In this paper, a P-type fuzzy controller to realize the variable switching sector scheme and a PID-type fuzzy switching frequency regulator are adopted. A meaningful contribution of this paper is to propose a simple realization scheme of the fuzzy switching frequency regulator. Simulation results show the effectiveness of those propositions.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.136-136
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• 2000

The direct drive servo valve(DDV) is composed of a DC rotor, link, valve spool and displacement sensor(LVDT) where the spool is directly coupled to the DC motor through the link. Since the DDV is a kind of one-stage valve, the robust controller is required to overcome the flow force effect on the spool motion. The mathematical equations are derived and the stability, accuracy and response speed of a DDV are investigated analytically using a linearized system block diagram. Proportional control, PID control. Time-Delay control, Sliding Mode control, and Proportional control using the load pressure are applied to DDV to find which one shows the best control performance. The digital computer simulation results show that the proportional control using the load pressure satisfies the design requirement of response speed and steady state error regardless of the variation of load pressure,

• Proceedings of the KOSOMBE Conference
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• v.1989 no.05
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• pp.77-80
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• 1989

This paper describes a study on the locomotion control system for a indoor-use mobile wheelchair. Three lode of operations - BASIC, AUTOMATIC and PROGRAMMED - are employed as basic algorithm building block. One-chip microcomputer 8031 is dominating the control of actuation part and it can control the range of rotating speed of the wheel both right and left by servo motor. Keyboard is employed as a command input device. This system is intended to improve the daily life of the disabled by the intelligent interactive operation scheme.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.671-677
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• 1996

This paper proposes a study on the effects of motion errors for acceleration/ deceleration types. The proposed motion errors are consisted of two errors : one due to transient response of servomechanism and the other due to gain mismatching of positioning servo motor. They are derived from using laplace transformation for the block diagram of general purpose feed drive system. In order to minimize them, the paper proposes second order polynomial regression model by using orthogonal array method which describes one of experimental methodolgies. The validity and reliability of the study was veri lied on a vertical machining center equipped with FANUC 0MC through a series of experiments and analyses.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.8 no.2
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• pp.193-198
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• 1997

Stuttering is a movement disorder of speech-motor control characterized by inappropriate timing of lingual, labial, laryngeal, and respiratory muscles. Treatment for adult stutterers have included traditional and non-traditional behavioral and psychiatric modalities, many with good initial success but all with limited long-term benefit. Recent trials of botulinum toxin injection was somewhat favorable. In this study, the authors injected 5-8 U of botulinum toxin into the thyroarytenoid muscle bilaterally in cases of disabling stutterers. Evaluation after 4 weeks of injection, 80% of the patients was improved more than one positive scale. However, no one was improved to almostly normal range.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.2
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• pp.149-156
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• 2017

Various kinds of accessories(e.g., clock, radio, automatic door locks, alarm devices, etc.) or unit components (e.g., black box, navigation system, alarm, private audio, etc.) require dark current even when the vehicle power is turned off. However, accessories or unit components can be the causes of excessive dark current generation. It results in battery discharge and the vehicle's failure to start. Therefore, immediate detection of abnormal dark current and response are very important for a successful repair job. In this paper, we can increase the maintenance efficiency by presenting a standardized diagnostic process for the measurement of the dark current and the existing problem. As a result of the absence of a system to block the dark current in a vehicle, diagnosis and repair were performed immediately by using a standardized dark current diagnostic process.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.363-365
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• 2005

KHSR(Korean High Speed Railway) had achieved the maximum speed of 350 km/h last year. And then, we have concentrated to improve the reliability of the overall system, in particular, motor block of the locomotive. In this paper, simple technique for operating PWM converters under the voltage distortion is introduced. In addition, the electrical braking technique is also made to have the braking capability under the dead zone. Test results revealed the verification of the proposed techniques.