• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 F
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• pp.2129-2131
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• 1997

A sensorless controller of induction motor has several advantage: availability in a harsh environment. In this paper, the speed information is driving from the currents and the estimated stator flux. To obtain the estimated stator flux, this study is using The Estimator. The simulation results show that the proposed scheme has activity over a wide speed range and good response to load variations

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(1)
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• pp.216-222
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• 2003

Today we have excellent motor drive system using high frequency carrier PWM control voltage source inverter in the other hand, we have met serious problems caused by high frequency switching. PWM Cyclo-converter called Matrix converter is expected as the new strategy Possible to improve these problems and add some more convenient features suitable for new drive system. in this Paper, we will introduce the background, features and outline of this converter, and additionally introduce some remarkable activity on this converter

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.509-511
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• 1997

A sensorless controller of induction motor has several advantage availability in a harsh environment. In this paper, the speed information is driving from the currents and the estimated stator flux. To obtain the estimated stator flux, this study is using the Estimator. The simulation results show that the proposed scheme has activity over a wide speed range and good response to load variations.

• 대한감각통합치료학회지
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• 제3권1호
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• pp.13-21
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• 2005

Objective : The purpose of this study was to investigate the correlation between hand dexterity and visual-motor skills of preschoolers. We searched for the correlation between two test results, which were the 9-Hole Peg Test performance time and the visual motor integration test(VMI) performance score. Then, we also compared the 9-Hole Peg Test performance times with the VMI performance scores according to sex and age. Method : The participants were fifty normal children ranging in age from four to six years living in Busan. We used two test methods which have high reliability and validity. One was the 9-Hole Peg Test to evaluate hand dexterity, and the other was the VMI to the evaluate visual-motor skills of these young children. Results : First, over the entire range of the participating children, there was a high correlation between the performance times from the 9-Hole Peg Test and the VMI performance scores(r=-.682). Second, there was not a statistically significant difference between the performance times from the 9-Hole Peg Test and the VMI scores according to sex. Third, there were significant differences between the hand dexterity and visual-motor skills according to the children's age(p<.001). Conclusion : This study proved that there is high correlation between hand dexterity and visual-motor skills of the preschooler. Occupational therapists in preschool service should consider that visual-motor skills need to be compatible with hand dexterity in both evaluation and therapy. In addition, hand dexterity and visual-motor skills improved according to advances in age, so we must give graded tasks to proper age groups through concrete analysis of activity. By doing this, children can get the better therapeutic effects.

• 대한감각통합치료학회지
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• 제15권1호
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• pp.21-32
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• 2017

목적 : 지각운동프로그램이 주의력결핍과잉행동장애(Attention-Deficit/Hyperactivity Disorder; ADHD) 아동의 시각운동통합기술과 운동기술에 미치는 영향을 알아보고자 한다. 연구방법 : ADHD로 진단 받았으나 약물중재를 받고 있지 않는 8세 남아를 대상으로 실시하였다. 실험설계는 개별실험연구(single-subject research design) 중 A-B-A(follow up) 설계를 사용하였고, 기초선 A는 3회기, 중재기 B는 8회기, 추적기간 A는 3회기였다. 기초선기간과 추적기간에는 자유 놀이를 40분간 실시한 후 시각운동통합기술을 보기 위해 한국판시지각발달검사의 하위 항목인 따라 그리기와 운동기술을 보기 위해 줄넘기를 실시하였다. 중재기 B에는 지각운동프로그램을 40분간 제공한 후 한국판시지각발달검사의 하위 항목인 따라 그리기와 줄넘기를 실시하였다. 결과 : 시각운동통합기술을 측정하기 위한 따라 그리기 항목의 표준점수는 기초선 기간에는 평균 4.7점의 열등수준을 보였지만 중재기간에서는 평균 9.6점의 평균 수준을 유지하였으며, 추적기간에서는 7.7점의 평균이하의 수준을 보였다. 아동의 운동기술의 변화를 측정한 줄넘기에서는 기초선 기간에는 4.3회, 중재기간에서는 5.9회로 증가된 운동능력을 보였으나, 추적기간에서는 5회로 약간 감소하였다. 결론 : 지각운동프로그램이 ADHD 아동의 시각운동통합기술과 운동기술의 수행의 변화에 긍정적 효과가 있었다.

• 조명전기설비학회논문지
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• 제22권10호
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• pp.111-117
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• 2008

일반적으로 산업현장에서 널리 사용되는 유도전동기는 상용인버터를 이용하여 속도제어를 하게 된다. 상용인버터로 구동되는 유도전동기는 인버터의 고속 스위칭에 의한 마이크로 서지전압을 발생한다. 이러한 마이크로 서지는 전동기의 소손뿐 만아니라 PLC 제어계통에 있어서 노이즈 문제를 발생하며, 생산 활동에 막대한 지장을 초래하게 된다. 본 논문에서는 마이크로 서지의 발생 메커니즘을 살펴본 후 전동기 소손 방지를 위한 대책을 제시하고 인버터 출력단에 LCR 필터를 부착하여 실험하였으며 결과로 마이크로 서지전압이 저감됨을 확인하였다 또한 PLC 제어계통의 노이즈 억제에 대해 이론적 고찰을 통해 대책도 제시하였다.

• BMB Reports
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• 제55권12호
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• pp.621-626
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• 2022

Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease characterized by the degeneration of motor neurons in the spinal cord. Main symptoms are manifested as weakness, muscle loss, and muscle atrophy. Some studies have reported that alterations in sphingolipid metabolism may be intimately related to neurodegenerative diseases, including ALS. Acid sphingomyelinase (ASM), a sphingolipid-metabolizing enzyme, is considered an important mediator of neurodegenerative diseases. Herein, we show that ASM activity increases in samples from patients with ALS and in a mouse model. Moreover, genetic inhibition of ASM improves motor function impairment and spinal neuronal loss in an ALS mouse model. Therefore, these results suggest the role of ASM as a potentially effective target and ASM inhibition may be a possible therapeutic approach for ALS.

• Journal of Preventive Medicine and Public Health
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• 제46권sup1호
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• pp.35-42
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• 2013

A commitment to physical activity is necessary for personal health, and is a primary goal of physical activity practitioners. Effective practitioners rely on theory and research as a guide to best practices. Thus, sound theory, which is both practical and parsimonious, is a key to effective practice. The purpose of this paper is to review the literature in search of such a theory - one that applies to and explains commitment to physical activity in the form of sport and exercise for youths and adults. The Sport Commitment Model has been commonly used to study commitment to sport and has more recently been applied to the exercise context. In this paper, research using the Sport Commitment Model is reviewed relative to its utility in both the sport and exercise contexts. Through this process, the relevance of the Investment Model for study of physical activity commitment emerged, and a more parsimonious framework for studying of commitment to physical activity is suggested. Lastly, links between the models of commitment and individuals' participation motives in physical activity are suggested and practical implications forwarded.

• 대한물리의학회지
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• 제14권4호
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• pp.71-80
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• 2019

PURPOSE: This study examined whether a task-oriented training program is an effective intervention to improve the body function, activity, and participation of children with cerebral palsy (CP). METHODS: Ten children with CP (7-13 years old) performed a task-oriented training program for eight weeks (three sessions per week, 30 minutes each). The taskoriented training program consisted of eight activities. The subjects' body function was assessed using a handheld dynamometer, goniometer, Modified Ashworth Scale (MAS), Balance Performance Monitor (BPM), and the Bruininks-Oseretsky Test of Motor Proficiency (BOTMP). The subjects' activity and participation were assessed using the Gross Motor Function Measure (GMFM) and Timed Up and Go (TUG) test. RESULTS: Task-oriented training provided significant improvements in the subjects' body function. The subjects improved the bilateral isometric muscle strength of the hip flexors, extensors and abductors, knee flexors and extensors, and ankle dorsi- and plantar flexors (p<.05). Bilateral passive hip flexion, abduction, and external rotation, knee flexion, and ankle dorsi- and plantar flexion were also increased (p<.05). In addition, the MAS score of the hip adductors decreased (p<.05) and the BOTMP score increased after training (p<.05). The subjects' activity and participation also improved significantly after training, increasing the GMFM score (p<.05) and decreasing the TUG score (p<.05). On the other hand, the BPM score did not change after training. CONCLUSION: This study suggests that a task-oriented training program can be an effective intervention to improve the body function, activity, and participation for children with CP.

• 디지털융복합연구
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• 제13권6호
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• pp.205-212
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• 2015

본 연구에서는 거울되먹임치료를 이용하여 뇌졸중 환자의 상지 근육 활성도와 상지 기능적 평가에 미치는 효과에 대하여 알아보고자 하였다. 환자는 거울되먹임 치료군 8명과 동작관찰 훈련군 8명으로 나누어 총 8주간 주 5회, 30분간 시행하였고, 상지 기능을 평가하기 위해 뇌졸중 기능회복 평가와 도수 기능 검사를 이용하였다. 위등세모근, 중간어깨세모근, 위팔두갈래근, 노쪽손목굽힘근, 긴노쪽손목폄근의 근활성도를 평가하기 위해 표면 근전도 시스템을 이용하였고, 연구 결과 노쪽손목굽힘근을 제외한 위등세모근, 중간어깨세모근, 위팔두갈래근, 긴노쪽손목폄근의 근활성도와 뇌졸중 기능회복 검사, 도수 기능 검사 점수에서 대조군과 실험군 모두 전, 후 유의한 차이를 보였다. 이에 따라 거울되먹임 치료가 동작관찰 훈련보다 상지 근활성도와 상지 기능을 향상시키는데 효과적임을 알 수 있었다.