• 한국안전학회지
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• 제15권1호
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• pp.153-160
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• 2000

Occupational cumulative traumas (CTDs) are becoming one of leading ailments in industrialized worl $d^{(1.2)}$. The degree of muscle fatigue is important parameter to understand cause of occupational cumulative trauma disorders. To quantify degree of muscle fatigue, muscle EMG activity was measured during isometric and dynamic contractions(repetitive concentric/eccentric muscle contraction) and its analyzed data, such as RMS, median frequency, and median power were compared when the muscle was fresh and exhausted. When muscle become fatigue, it was observed that median frequency decreased and median power and RMS increased However, based on overall prolonged observation, median frequency increased and median power and RMS decreased. Therefore it was concluded that shifting patterns of RMS, median frequency, and median power values can be used as parameter to evaluate degree of muscle fatigue even in dynamic muscle contraction.

• The Journal of Korean Physical Therapy
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• 제28권3호
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• pp.189-194
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• 2016

Purpose: This study focuses on influence of ankle stabilization training on balance ability and lower limb muscle activation of soccer player with functional ankle instability. Methods: Subjects were grouped into ankle stabilization training group using biofeedback comprised of 15 subjects and general exercise group of 15. The training was conducted for 30 minutes, 3 times a week for 8 weeks in total. All 30 football players conducted plyometric training for 30 minutes before main training. To evaluate balance ability, biorescure was used to measure whole path length and surface area and surface electromyography (EMG) system was used to measure tibialis anterior, tibialis posterior, and soleus to evaluate lower limb muscle activation. Results: The experiment group showed significant difference to the comparison group in regard of whole path length and surface area which represents balancing capability and muscle activation of tibialis anterior, tibialis posterior, and soleus. Conclusion: Therefore, ankle stabilization training using biofeedback is more effective in enhancing balance ability and lower limb muscle activation than general exercise.

• 대한음성언어의학회:학술대회논문집
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• 대한음성언어의학회 1998년도 제10회 학술대회 심포지움
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• pp.198-198
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• 1998

성악발성 시 전문적인 성악가와 비전문가에서 성대외근의 수축 경향을 파악함으로써, 성대외근이 성악발성에 갖는 중요성을 파악하고, 얻어진 자료를 토대로 성악발성 숙련도의 판정이나 성악인의 음성치료에 활용할 수 있는 가능성을 알아보고자 하였다. 서양음악을 전공한 지 10년 이상 된 20-30대의 소프라노 4인을 성악가 군으로, 비전공자 여성 4인을 대조군으로 하여, E3 부터 C6 내의 9개 음을 낮은 음부터 시작하여 차례로 /이/ 모음을 수초간 발성하게 하였다. Multi-Mode Program (UP) Plus (Nicolet, Viking IV)와 1개 채널의 음성신호 및 3개 채널의 surface electrode를 이용하여 발성 시설골상근, 설골하근, 견갑설골근의 활동전위를 측정한 뒤, 단위시간 당 근전위 진폭의 합을 구하여 두 군간에 그 양상을 비교하였다. (중략)

• International Journal of Computer Science & Network Security
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• 제22권1호
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• pp.129-138
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• 2022

With the increasing reliance of computing systems in our everyday life, there is always a constant need to improve the ways users can interact with such systems in a more natural, effective, and convenient way. In the initial computing revolution, the interaction between the humans and machines have been limited. The machines were not necessarily meant to be intelligent. This begged for the need to develop systems that could automatically identify and interpret our actions. Automatic gesture recognition is one of the popular methods users can control systems with their gestures. This includes various kinds of tracking including the whole body, hands, head, face, etc. We also touch upon a different line of work including Brain-Computer Interface (BCI), Electromyography (EMG) as potential additions to the gesture recognition regime. In this work, we present an overview of several applications of automated gesture recognition systems and a brief look at the popular methods employed.

• 한국전문물리치료학회지
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• 제7권2호
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• pp.88-95
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• 2000

Thirty normal adults were tested to measure the electrical activity of the anterior (AD), middle (MD), and posterior portion (PD) of the deltoid muscle and sternal portion of the pectoralis major muscle (PM) during the performance of four upper extremity PNF diagonal patterns with elbow flexion angle in $0^{\circ}$, $45^{\circ}$, and $90^{\circ}$. The PNF patterns in which these muscles function optimally have been theoretically advanced by Kabat and further described by Knott and Voss. They theorize that the MD should be most active with shoulder flexion, abduction, and external rotation (D2F); the PD with shoulder extension, abduction, and internal rotation (D1E); the AD with shoulder flexion, adduction, and external rotation (D1F); and the PM with shoulder extension, adduction and internal rotation (D2E). The patterns were performed through range of motion, with an isometric contraction performed in the shortened range. When the EMG activity of AD, MD, PD and PM in its optimal patterns was measured, it does not have significant difference among fixed elbow flexion angle $0^{\circ}$, $45^{\circ}$, and $90^{\circ}$ (p>.05). In addition, suggestions were made for study of patients who exhibit imbalance of muscle strength and have muscle weakness.

• 한국전문물리치료학회지
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• 제24권3호
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• pp.30-39
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• 2017

Background: Scapular posterior tilt (SPT) is important in the prevention of abnormal scapular movement and pain during elevation of the arm. However, previous studies have overlooked increased upper trapezius (UT) muscle activity interrupting the normal force couple of scapular motion and compensation of levator scapulae (LS) muscle activated simultaneously with UT during SPT exercise. Objects: The purpose of this study was to compare the effects of modified SPT with depression exercise versus SPT exercise on serratus anterior (SA), lower trapezius (LT), UT, and LS muscle activities and the clavicular tilt angle, in subjects with rounded shoulder posture (RSP) and myofascial pain in the UT muscle region. Methods: Eighteen subjects with RSP were recruited and randomly allocated to 2 groups; 9 in the SPT group and 9 in the SPT with depression group. All subjects met the specific RSP criteria and had myofascial pain of UT region. Depending on the allocated group, subjects performed the assigned SPT exercise and EMG data were recorded during the each exercise. Clavicular tilt angle was defined as the angle between the line joining the medial and lateral end of the clavicle and a horizontal line. Results: The SA muscle activity was significantly greater in SPT with depression than with SPT exercise (p<.05). The UT, LS muscle activity and the clavicular tilt angle was significantly lower in SPT with depression than with SPT exercise (p<.05). Conclusion: These findings were insightful because the potential risk of pain from overactivation of the UT and LS was considered, in contrast with SPT exercise. SPT with depression exercise can be implemented as an effective method to facilitate scapular muscle activity for stability and to prevent myofascial pain in the neck and shoulder.

• 한국운동역학회지
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• 제25권1호
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• pp.21-28
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• 2015

Objectives : The purpose of this study was to compare differences in muscle activities according to distance changes, and success or failure in relation to approaches during a round of golf in order to obtain basic data on golf swings. Methods : To achieve our research goal, we asked eight professional golfers playing for the Korea Professional Golfers' Association (height: $1.76{\pm}0.05m$, weight: $73.87{\pm}9.21kg$, career duration: $12.87{\pm}4.48yr$) to perform approach swings at distances of 30, 50, and 70 m. Results : No differences were observed in the muscle activity of the extensor carpi radialis that were caused by the distance changes. In addition, we found that the wrist extensors seemed unaffected by the increase in approach distance. Also, we found that the powers of the approach shots were driven by efficient movements rather than by the strength of the arms. We confirmed that when the distance of the approach increased, the golfers should perform their back-swing tops and follow-through right from the right to the left pelvic limb. To achieve successful approach swings despite distance changes, golfers should first work on the activity of the erector spinae to prepare for rotatory power in the P1 section. Moreover, golfers should increase the activity of the erector spinae on the left when they need to deal with the distance improvements in the P2 and P3 sections. Conclusion : In the light of the discussion above, we may infer that despite approach distance changes during a round of golf, ideal swings can be realized by consistent activities of the wrist extensor muscles and improved performances of the pelvic limb muscles. Furthermore, this study suggests that golfers should improve the consistency of muscle activities in all the other body parts to achieve the ideal swing.

• 한국전문물리치료학회지
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• 제17권1호
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• pp.17-25
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• 2010

The aim of this study was to investigate the effect of supporting surface instability to trunk and lower extremity muscle activities during bridging exercise combined with core-stabilization exercise. Thirty young healthy adults (15 males and 15 females) voluntarily participated in this study. Each subject was asked to perform bridging exercise combined with core-stabilization exercise on three different supporting surfaces (stable ground surface, the wooden balancing board, and the air cushion). The muscle activities were measured using surface electromyography (EMG) during performing exercise. To test statistical significance, one-way ANOVA with repeated measures was used with the significance level of .05. The findings of this study are summarized as follows. (1) There were significant differences in muscle activities on internal oblique, external oblique, gluteus medius, semitendinosus, biceps femoris, medial gastrocnemius and lateral gastrocnemius during exercise (p<.05). (2) The biceps femoris and lateral gastrocnemius showed significantly higher muscle activity on the wooden balancing board rather than on the ground, and semitendinosus, biceps femoris, medial gastrocnemius and lateral gastrocnemius showed significantly higher muscle activity on the air cushion rather than on the ground (p<.05). Therefore, it is concluded that muscle activities in the trunk and the lower limbs during bridging exercise combined with core-stabilization exercise was affected with instability of supporting surface. Further researches are needed to investigate the long term effect of bridging exercise on muscle activity with patient group.

• 한국전자통신학회논문지
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• 제8권5호
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• pp.763-769
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• 2013

본 연구는 넙다리 부위의 근력 증진을 위해 순수 저항운동과 유산소 병행 저항운동의 효과를 비교해 임상에서 근력증진을 목적으로 한 운동 프로그램의 근거자료를 제공하고자 하였다. 넙다리 곧은근의 근활성도는 두 군 모두 실험전에 비해 실험후 통계적으로 유의한 차이가 있었고, 측정시기에 따른 군간 비교에서 순수 저항 운동군에 비해 유산소 병행 운동군이 통계적으로 유의한 차이가 있었다. 넙다리 곧은근의 두께는 두 군 모두 실험전에 비해 실험 후 유의한 차이가 없었으나, 측정 시기에 따른 군간비교에서 실험후에 순수 저항 운동군에 비해 유산소 병행 저항 운동군이 통계적으로 유의한 차이가 있었다. 결론적으로 근력 증진을 목적으로한 순수 저항 운동보다 저항 운동 후 유산소 운동을 실시하는 유산소 병행 운동이 근활성화 및 근 비대에 더 효과적임을 알 수 있었다.

• 한국콘텐츠학회논문지
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• 제10권8호
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• pp.283-291
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• 2010

이 연구의 목적은 인체모형을 이용하여 옮기기 활동을 하는 동안 발의 배치(11자 배치와 $90^{\circ}$배치)와 옮기는 지면의 높이(휠체어 좌석과 같은 높이와 다른 높이)가 허리척추에 미치는 영향을 알아보는 것이었다. 자발적으로 실험참여에 동의한 건강한 남성 15명을 대상으로 4가지 조건에 따라 옮기기 활동을 실시 하였다. 옮기기 활동 동안 허리척추의 작업부담을 알아보기 위해, 위팔두갈래근, 척추세움근, 넙다리근의 근활성도를 표면근전도로 측정하였고, 힘판을 이용하여 수직 지면반발력을 측정하였고, L4/L5에 가해지는 압박력을 3DSSPP를 이용하여 측정하고 분석하였다. 그 결과, 오른쪽 넙다리근의 근활성도를 제외한 나머지 근육의 근활성도는 각 조건 사이 유의한 차이가 없었다. 수직 지면반발력은 각 조건 사이 유의한 차이가 있었다(p<.05). 또한 L4/L5에 가해지는 압박력은 같은 높이인 경우 발의 배치에 따라 유의한 차이가 있었다(p<.05). 따라서 옮기기 시 발을 11자로 배치하는 것보다 발을 90°로 배치하는 것이 체중이 한쪽으로 쏠리는 경향과 L4/L5 압박력을 줄이는데 도움이 되기 때문에 환자 옮기기 시 이를 적용하는 교육이 필요할 것이다.