• 대한인간공학회지
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• 제30권2호
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• pp.339-347
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• 2011

Objective: The purpose of this study was to evaluate of various material of pillows by using biomechanical variables such as the cervical stability, head pressure distribution, and muscle activity. Method: Eight subjects participated in the experiment. Three different materials such as polyester sponge, memory foam and the buckwheat shell used for Korean traditional pillow were tested. Electro-goniometer, six channels of electromyography(EMG), ten channels of the head pressure sensors were used to measure the biomechanical responses. Surface electrodes were attached to the right/left semispinals capitis(RSC, LSC), the right/left sternocleidomastoid(RSM, LSM), the right/left upper trapezius(RUT, LUT). The cervical stability was evaluated by the angle deviated from the standing neck position. The head pressure distribution was evaluated by the pressure per unit area recorded on the sensors and the intensity of peak pressure. Electromyography(EMG) data were analyzed by using root mean square(RMS) and mean power frequency(MPF). Results: The buckwheat shell material showed a higher stability in the cervical spine then the other pillows during spine position. In terms of head pressure distribution, the memory form indicated the lowest pressure at supine position, buckwheat shell material indicated the lowest pressure during lying down to side, and polyester cushion recorded the highest pressure at all postures. Conclusion: The buckwheat shell material has a biomechanical advantage to maintain a healthy neck angle and reduce the pressure on the head, which means the buckwheat shell is a potential material for ergonomic pillow design. The pillow with memory form showed second best biomechanical performance in this study. Application: The shape of the buckwheat shell pillow and the characteristics of materials can be used to design the pillow preventing neck pain and cervical disk problems.

• 한국콘텐츠학회논문지
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• 제16권10호
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• pp.711-718
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• 2016

본 연구는 이중과제 훈련이 만성기 뇌졸중 환자들의 균형 능력 및 상지기능에 미치는 효과를 알아보고자 실시되었다. 경상북도 A병원에 내원한 뇌졸중 17명을 대상으로 하였으며, 이중과제 훈련은 전 후 평가를 제외한 총 4주 동안 주 5회 30분씩 실시하였다. 평가도구는 버그균형 척도(Berg Balance Scale), BTS FreeEMG 300(BTS FreeEMG 300, BTS, Italy)이 사용되었다. 연구 결과 이중과제 훈련 실시 전에 비하여 실시 후 만성기 뇌졸중 환자들의 BBS 점수에서 유의미한 변화가 나타났고(p<.05), CCR값에서도 어깨 및 팔꿈치 관절 동작 모두에서 음의 값이 나타나 긍정적인 변화가 있었다. 본 연구의 결과로 볼 때 이중과제 훈련이 만성기 뇌졸중 환자들의 균형 능력 및 상지기능 향상에 긍정적인 효과의 가능성을 확인할 수 있었다.

• 재활치료과학
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• 제9권4호
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• pp.7-20
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• 2020

목적 : 본 연구는 뇌졸중 환자들의 상지기능 개선을 위해 말초신경감각자극과 과제지향적 훈련의 동시적용하여 효과를 알아보는 것이다. 연구방법 : 본 연구는 29명의 편마비 환자를 대상으로 수행하였다. 말초신경감각자극과 과제지향적 훈련을 동시에 적용한 실험군은 14명, 과제지향적 훈련만 실시한 대조군은 15명으로 주5회, 회기당 30분씩, 총 4주간 진행하였다. 결과측정은 손목과 어깨근육의 자발적 근수축 비율과 상자와 나무토막 검사, 잡기와 쥐기의 근력, Action Research Arm Test를 사용하여 중재 전·후로 측정하였다. 결과 : 4주간의 중재 후 짧은노쪽손목폄근, 노쪽손목굽힘근의 근 활성도와 잡기 근력, Action Research Arm Test에서 실험군은 대조군 보다 유의한 개선을 나타냈다. 결론 : 말초신경감각자극과 과제지향적 훈련의 동시적용은 과제지향적훈련만 하는 것보다 뇌졸중 환자의 상지기능 개선에 보다 효과적이었다.

• 대한인간공학회지
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• 제33권6호
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• pp.565-575
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• 2014

Objective: The aim of this study is to evaluate the effect of weight of load and time on the physical workload of repetitive upper-limb tasks with handling light weight loads using EMG and perceived discomfort, and to investigate the relationship between EMG and perceived discomfort for those repetitive tasks of moving light weight loads. Background: Repetitive upper-limb motion is known as one of the main risk factors of musculoskeletal disorders, and a lot of repetitive tasks are carried out while handling light weight loads in the industry. In evaluating the workload of repetitive tasks handling light weight loads, EMG and perceived discomfort can be used, though their relationship in those work conditions are not much investigated. Method: A laboratory experiment with 18 healthy males were conducted to record EMG signals from 5 muscle sites of the right arm and shoulder and rate perceived discomforts for the body parts and the whole body while carrying out repetitive materials-handling tasks for 52min. The subjects were divided into 3 groups which handled the loads of 1kg, 2kg and 3kg, respectively. ANOVAs were conducted to analyze the effects of the weight and time on RMS of EMG amplitude (normalized RMS: NRMS), median frequency of power spectrum of EMG (normalized MDF: NMDF) and perceived discomfort. The correlations between NRMS and NMDF and perceived discomfort were also analyzed. Results: Statistically significant muscular fatigue effects were not found from NRMS and NMDF in most muscles, while there were significant increases of discomfort as the task time elapsed. It was shown that there were an increasing trend of the muscular activity as the weight of load increased and a decreasing trend of median frequency of EMG of upper and lower arms as time elapsed. It was found that there were significant negative correlations between NMDFs from the lower arm and discomfort ratings, though the relationships were weak. Conclusion: It can be concluded that the working conditions adopted in this study were not enough to induce muscular fatigue, while there was significant increase in perceived discomfort. A further study is necessary to integrate the objective and subjective measures for more reliable and sensitive evaluation of workload of repetitive tasks of handling light weight loads. Application: This study can be used as a basic study for the evaluation of workload of repetitive tasks handling light weight loads.